Indian Patents
Title of Invention

STORAGE-STABLE PRODUCT SYSTEMS FOR PREMIX FORMULATIONS
Abstract The present invention relates to storage-stable product systems having high latency and good mechanical stability, which are suitable, inter alia, for premix formulations. Furthermore, the present invention relates to a method for producing the formulations according to the invention and the use thereof.
Full Text

Storage-stable product systems for premix formulations
The present invention relates to storage-stable product
systems with high latency and good mechanical stability
which are suitable, inter alia, for premix formulations. In
addition, the present invention relates to a method for
producing the formulations according to the invention, and
to the use thereof.
The formulation of active ingredients to give product
systems which permits the delayed release of active
ingredients has considerable advantages over the
conventional administration of active ingredients. Thus,
the dosage of the active ingredients and the site of
release can be controlled and the active ingredients can be
continuously released over a prolonged period.
Consequently, it is often possible to achieve better
utilization and a reduction in the required amount of
active ingredients, which in term reduces side-effects,
reduces the environmental impact and conserves natural
resources.
Product systems for the controlled release of sensitive
active ingredients are also known from the literature.
These systems are used in order to avoid undesired
conversion or decomposition and to improve the storability
of sensitive active ingredients. Furthermore, for some
usages, for example in the area of construction chemicals
or in the case of adhesives, handling advantages can be
attained.
In the field of pharmaceutical products, a targeted release
of the active ingredients in a pregiven area of the body is
often desired. Product systems have likewise been developed
for these aims. Product systems with delayed active
ingredient release are likewise often used in the
pharmaceutical sector. Here, it is a case of administering
an active ingredient as uniformly as possible over a

prolonged period or releasing the active ingredient at
certain sites in the human or animal body. A comprehensive
report on this can be found, for example, in "Modified-
Release Drug Delivery Technology" (M.J. Rathbone,
J. Hadgraft, M.S. Roberts, editors). Marcel Dekker Inc.,
New York, 2003. Similar product systems have also been
developed for controlled release of pesticides and other
crop protection compositions. A comprehensive overview on
this subject can be found in Park et al., "Controlled
release of pesticides from microparticles", pages 89-136
in: Controlled-Release Delivery Systems for Pesticides
(H.B. Scher, editor). Marcel Dekker Inc., New York, 1999.
One concept that is often used for targeted active
ingredient release is based on the embedding of the active
ingredient in a suitable matrix, the matrix in most cases
being an organic polymer substance. The matrix can be
designed such that the active ingredient passes by
diffusion through the matrix or, as a result of the erosion
or breakup of the matrix, slowly to its surface, where it
is brought into contact with a suitable solvent. In another
variant, the matrix material is designed such that a
solvent diffuses through the matrix material and thus
arrives at the active ingredient. Both systems have the
disadvantage that the diffusion is a relatively slow
process and relatively large amounts of active ingredient
cannot be released all at once. Both systems are therefore
suitable only for fields of use where what matters is long-
lasting, uniform active ingredient release. Furthermore, in
the case of such a particle structure, a considerable part
of the active ingredient is located directly on the
surface, which very often can lead both to the
decomposition of sensitive active ingredients during
storage, and also to the undesired immediate release of the
active ingredient. This problem is particularly marked when
the product system is synthesized in the form of
microparticles having an average diameter below 200 urn.

Examples of systems with an organic matrix are the products
described in WO 2004/072153 and WO 03/033027. A
disadvantage here is the low stability, in particular the
low pressure loadability of these systems, where this low
loadability can cause problems during storage. Furthermore,
the use of these products is often limited to less
chemically aggressive active ingredient.
Another system involves the binding of an active ingredient
into a porous carrier material, e.g. an inorganic oxide, -
and closing parts of the pores by a protection system. This
leads to only some of the pores being accessible for a
solvent and thus the active ingredient release being
slowed. However, a disadvantage of this system is that the
system releases the active ingredient as soon as it comes
into contact with the solvent, i.e. in the case of soluble
active ingredients and premix formulations with at least
one corresponding solvent, such product systems are
unsuitable for targeted release of the active ingredient at
the site of application since the active ingredient comes
into contact with the solvent during the premixing and is
released.
A further development of the aforementioned product system
includes the complete covering of a porous carrier material
containing active ingredient with a protective layer such
that all of the pores are closed by the protective layer.
The active ingredient release can then take place either by
diffusion of the active ingredient through the protective
layer, which again is a slow process and generally leads to
incomplete active ingredient release. Alternatively, the
active ingredient can be released in such systems following
breakup of the protective layer. Since the protective layer
is applied outside of the carrier material, these systems
are very sensitive to mechanical stresses during
production, transportation or use of the product systems.
I.e. mechanical action leads to an at least partial

destruction of the protective layer, meaning that an
undesired release of active ingredient is thereby
triggered. Consequently, such systems can only be used in
specific areas. Examples of such systems can be found inter
alia in WO 02/098998, WO 00/51724, WO 2006/004481,
CH 573212, EP-A-0 454 881 and CA 2 438 438.
The products disclosed in the specification WO 02/098998
include an inorganic matrix which are produced by a sol/gel
process. In this process, firstly an active ingredient is
complexed with a carrier molecule and the product obtained
in this way is incorporated into a matrix which is produced
by a sol/gel process. These methods are costly and complex
in terms of handling, with product release taking place via
the cavities produced during the formation of the matrix.
As a result of this, no active release of the components is
made possible, rather the substances are fixed in a matrix
and released in the presence of a solvent without it being
possible to control the time of release. Thus, the release
of the active ingredient takes place directly by adding
solvent. Release at a later time is not possible.
The specification WO 2006/004481 discloses an additive for
feeds which has antimicrobial properties. The additive
comprises a porous carrier and also acids which have been
incorporated into the carrier as active ingredients. To
control the release, the system comprises a core with a
strong acid and an outer layer which comprises an acid
which has a higher pH than the acid in the core. Release is
controlled here via a diffusion control, it being possible
for the outer layer to be porous in order to permit
diffusion of the acid from the core outwards.
Furthermore, the document WO 00/51724 describes a system
for the controlled release of active ingredients which
comprises an inorganic matrix. Release of the active
ingredient can be controlled by diffusion. This means that
the release rate can be influenced via the pore size.

However, systems of this type cannot therefore be stored
together with a liquid in which the active ingredient is
soluble since the active ingredient inevitably diffuses
into the solution. Although WO 00/51724 also explains the
option of a controlled release of the active ingredient,
with various control signals being described, a specific
solution for the problem of a release controlled by an
external signal is not described.
Furthermore, the specification CH 573212 describes a
composition which can be used in particular in agriculture.
This composition comprises a porous carrier material, for
example kieselguhr, an active ingredient and a protective
layer, for example made of organic compounds, which brings
about a delay in the active ingredient release. The
protective layer here is soluble in a solvent, in
particular water. Upon contact with water, the protective
layer is broken up after a time determined by the
solubility of the protective layer. Following the breakup
of the protective layer, the active ingredient is released
with diffusion control. A disadvantage of this system,
however, is poor handling, which hinders processing of
these systems. Upon contact with moisture, these systems
often have a tendency toward aggregation, as a result of
which controlled application is hindered. A mixing of this
composition with further substances may also lead to
problems associated with observing mixing ratios.
The application EP-A-0 454 881 describes a composition
which comprises a porous carrier material which is laden
with an acid. Furthermore, the composition has a plurality
of layers which permit controlled release of the acid,
where the outermost layer can comprise compounds
("anticoalescent") which can prevent agglomeration of the
particles. The release of the acid can take place via
various methods, each of which is associated with a breakup
or,a destruction of the protective layers. A disadvantage

here is in particular the processability or handling of the
particles. For example, in the event of inappropriate
handling of the composition, the acids can be released
undesirably. This is particularly critical for plants in
which these compositions are processed since the acids can
lead to corrosion of the plants. Plants made of acid-
resistant materials, however, are expensive. If plants of
this type are used, then the acids can also be processed
directly.
Document CA 2 438 438 discloses porous silicate particles
which are laden with active ingredient. The particles are
provided with a layer which permit controlled release of
the active ingredient. The particles described in this
document have the same problems which the particles
according to CH 573212 and EP-A-0 454 881 also exhibit.
There therefore continues to be a great need for suitable
product systems which have high stability to mechanical
stresses and permit rapid and as complete as possible an
active ingredient release at a certain site or from a
certain time. I.e. these product systems should as far as
possible release no active ingredient during storage and/or
during transportation to the site of action, but should
release the complete active ingredient as rapidly and
completely as possible at the site of action.
It was therefore an object of the present invention to
produce new types of product systems which do not have, or
have only to a reduced extent, the aforementioned
disadvantages of the product systems of the prior art. In
addition, the aim is to provide a method for producing such
product systems.
Further details not explicitly specified arise from the
overall context of the description, examples and claims of
the present invention.

Surprisingly, the aforementioned object is achieved by new
types of product systems as defined and characterized in
the claims of the present invention and also in the
description below. These new types of product systems are
characterized in that a carrier material is laden with at
least one active ingredient and at least one protection
system, where the protection system is arranged to the
greatest possible extent in the pores of the carrier
material and not on its surface. In addition, it is ensured
that all or largely all of the pores of the carrier
material are filled with the protection system in such a
way that no solvent can come into contact with the active
ingredient. In contrast to product systems in the prior
art, the product systems according to the invention have
the advantage that undesired active ingredient releases do
not result.
Moreover, the protection system of the product systems
according to the invention is designed so that it can be
deactivated in a targeted manner such that, spontaneously,
the entire active ingredient or at least a large part of
the total active ingredient -is released. The product
systems according to the invention thus have very good
latency. This latency can be designed such that, prior to
the deactivation, approximately no or no active ingredient
release can take place, but afterwards an active ingredient
release can take place spontaneously.
As a result of the fact that the protection system is
arranged for the greatest part or completely in the pores
and not as a coating around the carrier material, the
product systems according to the invention are insensitive
towards mechanical stresses. This means that the
formulations according to the invention can be incorporated
into premixes without the active ingredient being released.
During the production of premixes, on the one hand
mechanical forces act upon the particles (via the mixer),

but on the other hand the formulations according to the
invention also come into contact with the further
components of the premix formulation. The product systems
according to the invention can be incorporated into such
formulations without or largely without the active
ingredient being released. However, as soon as a certain
input of energy or a change in the chemical environment has
an effect on the premix, the active ingredient is
spontaneously released. Environmental influences, such as
e.g. humidity, and contact with solvents do not lead to a
premature active ingredient release, i.e. the product
systems according to the invention exhibit very good
latency. For example, active ingredients which should be .
present in foods, e.g. yoghurt, but should only be released
in the stomach are encapsulated with the product systems
according to the invention in such a way that they
withstand the incorporation into the yoghurt and the
storage without the active ingredient being released. Only
upon contact with the stomach acid is the active ingredient
then spontaneously released. Conventional product systems
with "core/shell" construction are not suitable for
achieving such an object since, upon incorporating the
product system into the yoghurt, i.e. the production of the
premix, at least parts of the shell are destroyed by the
mechanical influences, meaning that in the course of the
storage of the premix, active ingredient is gradually
removed from the formulation.
Moreover, the method according to the invention is cost-
effective and efficient since low-cost carrier materials, u
such as, for example, precipitated silicas, can be laden in
conventional apparatuses with the carrier material and the
protection system without special apparatuses being
required for this purpose. During packaging and
transportation it is also possible to dispense with special
measures, thus affording economic advantages.

Finally, it is possible, depending on the choice of
protection system and the trigger mechanism, to satisfy any
desired release scenarios in terms of time. Thus, for
example a mixture of two product systems can be produced in
which one part of the particles is equipped with a
protection system which releases the active ingredient upon
reaching a certain temperature, but the other part of the
particles does not release the active ingredient at this
temperature, but the active ingredient is released as a
result of a change in pH. Consequently, active ingredients
can also be released in a targeted manner to various sites.
Finally, it is also possible to permit a delayed active
ingredient release over a prolonged period, but which only
starts at a very specific time, i.e. which is preceded by a
latency time. In this embodiment of the present invention,
e.g. the active ingredient in a matrix from which it must
diffuse out could be incorporated into a carrier and
additionally the pores could be provided with a protection
system which only permits contact of the active ingredient
with a solvent after a targeted influence.
Moreover, as a result of the targeted active ingredient
release of the formulations according to the invention in
combination with the latency, undesired side-effects can be
avoided. For example, it is possible to produce product
systems according to the invention which have no kind of
active ingredient on the surface and moreover permit no
kind of contact between active ingredient and the
environment. This is not the case for systems in the prior
art with incomplete pore closure or diffusion mechanism.
Consequently, the present invention provides product
systems comprising
at least one inorganic and/or organic porous
carrier,

at least one active ingredient which is
introduced into the porous carrier, and
at least one further substance of the at least
part of the total amount present in the product
system is introduced in the pores of the carrier
material,
which are characterized in that, detected by investigating
the outermost atomic layer of the product system by means
of XPS, at least part of the outermost surface of the
product system is formed by the carrier material.
Also provided are product systems comprising
at least one inorganic and/or organic porous
carrier,
at least one active ingredient which is introduced
into the porous carrier, and
at least one further substance of the at least
part of the total amount present in the product
system is incorporated in the pores of the carrier
material,
characterized in that these further substance and/or
substances forms/form a protection system for the active
ingredient/active ingredients which is designed such that,
through a deactivation of the protection system as a result
of an input of energy and/or chemical conversion and/or
breakup of the protection system, the protection system is
changed in such a way that, preferably spontaneously, at
least 50% by weight of the active ingredient/active
ingredients is/are released.
Likewise provided by the present invention is a method for
producing a product system according to the invention,

characterized in that an active ingredient is introduced
into a porous carrier and a protection system is produced.
Finally, the present invention provides the use of the
particulate composition according to the invention for
producing foods, feeds, medicaments, products for the land
and forestry, cosmetics, components for coating
formulations and adhesive formulations or components for
sports equipment and sports clothing, and also said
articles per se.
The subjects of the present invention are described below
in detail. The terms used in the description, the drawings,
the claims and the abstract of the present invention are
defined as follows:
Within the context of the present invention, particulate or
particle refers to a three-dimensional body made of at
least one inorganic and/or organic material with a defined
outer shape which - depending on the size of the particle -
can be ascertained by means of microscopic methods (light
microscope, electron microscope etc.). The particles
according to the invention may be porous, i.e. have pores
and/or internal cavities.
The product system according to the invention comprises
at least one inorganic and/or organic porous
carrier,
at least one active ingredient which is introduced
into the porous carrier, and
at least one further substance of the at least
part of the total amount present in the product
system is introduced in the pores of the carrier
material,

characterized in that, detected by investigating the
outermost atomic layer of the product system by means of
XPS, at least part of the outermost surface of the product
system is formed by the carrier material.
It is essential that the largest possible part of the outer
surface of the product system according to the invention is
formed by the carrier material. In contrast to systems in
the prior art, in the case of the systems according to the
invention, the largest part of the total amount of active
ingredient(s) and protective substance(es) is located in
the pores of the carrier. Consequently, the protection
system cannot be damaged by mechanical influences as is the
case with systems in the prior art in which the pores are
filled completely, i.e. to the maximum absorption capacity,
with active ingredient, and the protective substance forms
an independent shell, as in the case of an onion skin,
around the carrier filled with active ingredient.
The carrier materials according to the invention are '
generally stable upon mechanical stresses such as
transportation and filling. As a result, the carrier
material protects the active ingredient/protective
substance system embedded therein. In the case of the
systems in the prior art, upon destruction of the outer
protective substance shell, the pores, which are filled up
to the edge with active ingredient, are exposed and the
active ingredient can escape, i.e. a targeted release of
active ingredient is no longer possible.
The product systems according to the invention are thus
characterized in that their outer surface is formed at
least partly by the carrier material. Preferably, at least
10%, particularly preferably at least 15%, very
particularly preferably at least 20%, of the outer surface
of the product systems according to the invention,
according to measurement of the outermost atomic layer by
means of XPS, is formed by the carrier material and not by

the molecules of active ingredient/active ingredients
and/or protective substance/protective substances.
For specific applications, it is also advantageous that the
outer surface of the product systems according to the
invention is free from active ingredient(s) so that these
active ingredient fractions do not trigger any premature
undesired reaction. In one particular embodiment of the
present invention, according to measurement of the
outermost atomic layer by means of XPS, no active
ingredient is located on the outer surface of the product
systems according to the invention, or at most 10%,
preferably at most 5%, particularly preferably at most 1%,
of the outer surface is covered by active ingredient.
The product system comprises at least one organic and/or
inorganic, preferably porous carrier material with active
ingredient(s) adsorbed or absorbed therein. The carrier
material per se is preferably insoluble or only slightly
soluble in water. It can, for example, be selected from the
group which consists of preferably precipitated, porous
carrier oxides of aluminum and/or of silicon and
phosphorus-containing substances, preference being given to
using silicas, silica gels, fumed silicas, aluminum oxides,
clays, sheet silicates, zeolites, diatomaceous earths, and
mixed oxides. They are particularly preferably precipitated
silicas or silica gels in the form of powders, granules or
microgranules having an average diameter d50 greater than
or equal to 3 µm. Particular preference is given to the
commercially available carrier silicas from Evonik Degussa
GmbH, e.g. Sipernat® 2200, Sipernat® 22, Sipernat® 50,
MagSilica, from Rhodia Chimie, e.g. Tixosil 38X or Tixosil
68 or PPG, e.g. HiSil SC 72 or HiSil SC 60. Comparable
carrier silicas from other companies, however, are likewise
suitable.
The unladen inorganic and/or organic porous carrier
material preferably have a DBP absorption (according to

DIN 53601) of at least 180 g/100 g. The pores accessible
for DBP are also accessible for the active ingredient and
the substances of the protection system, and a high DBP is
therefore important in order to achieve a high loading of
the pores of the carrier with active ingredient and
protective substance. Consequently, too low a DBP
absorption may, depending on the active ingredient, be
ineffective since too much carrier material has to be used.
The DBP absorption of the carrier material is preferably in
the range from 180 to 600 g/(100 g), particularly
preferably from 180 to 500 g/(100 g), very particularly
preferably from 200 to 500 g / (100 g) and especially
preferably from 240 to 500 g / (100 g), very particularly
preferably 240 to 400 g / (100 g) and specifically
preferably 240 to 350 g / (100 g).
Furthermore, it has proven to be advantageous if the
carrier material and preferably also the entire product
system are particulate. The particles of the carrier
material and/or of the product system particularly
advantageously have an average particle size d50 in the
range from 5 µm to 5000 µm, preferably 5 urn to 1000 µm,
particularly preferably from 5 to 500 µm, very particularly
preferably from 5 to 150µm and especially preferably from
10 to 100 µm. If the particles are too small, then
undesired dust formation may result. In addition, if the
outer surface compared to the inner surface is so large
that it becomes difficult or even impossible to prevent the
active ingredient being absorbed on the outer surface.
Excessively large particles in turn have the disadvantage
that they are often mechanically unstable and are
unsuitable for further processing. They are furthermore
often incompatible with the end formulation and have pores
which are too deep, meaning that the absorption and
desorption rates can be too slow and/or parts of the
absorbed active ingredient can no longer be desorbed.

It has proven to be advantageous if the weight ratio of
protective substance to active ingredient is in the range
from 10:1 to 1:10. The ideal ratio depends on the chemical
nature and the physiochemical properties of the active
ingredient and of the carrier material and also of the
protection system and can be determined for any material
combination by simple experimental series. Higher loading
of the carrier material can lead to protective substance no
longer being able to be introduced to an adequate extent
into the pores, meaning that the latency is no longer
ensured. Too little loading is not economically sensible.
Particularly preferably, the weight ratio of protection
system to active ingredient is in the range from 10:1 to
1:10, very particularly preferably in the range from 5:1 to
1:5 and especially preferably in the range from 2:1 to 1:3.
Besides the weight ratio, it may be advantageous, depending
on the material combination, to observe a certain ratio of
DBP absorption and absorbed amount of active ingredient.
Without being bound to one specific theory, the inventors
are of the view that DBP, the active ingredients to be
absorbed and the protective substances often have a similar
space requirement in the pores of the carrier material and
also penetrate into similarly sized pores. Consequently,
this ratio gives information about how much space is still
present in the pores accessible for the protective
substance and can thus ensure that an adequate amount of
active ingredient and also protective substance can be
introduced into the pores. It has thus proven to be
advantageous that the loading of the porous carrier with
active ingredient is at least 10% by weight to 90% by
weight, preferably 10% by weight to 80% by weight,
particularly preferably 20% to 70% by weight and very
particularly preferably 30% to 60% toy weight, based on the
DBP absorption of the porous carrier. In one specific
embodiment, the loading of the porous carrier with active

ingredient is 1% by weight to 9% by weight, based on the
DBF absorption of the porous carrier.
As already explained, one essential feature of the silicas
according to the invention is that the largest amount of
protective substance is present within the pores of the
carrier material and is not absorbed on the surface of the
carrier material. This can prevent the protection system
being damaged and deactivated e.g. by abrasion. For the
same reason, it has proven to be advantageous to state the
absorbed amount of protective substance relative to the DBP
absorption of the carrier material. It has proven to be
particularly advantageous if the loading of the porous
carrier with protective substance is at least 10% by weight
to 90% by weight, preferably 10% to 80% by weight,
particularly preferably 20% to 70% by weight and very
particularly preferably 20% to 50% by weight, based on the
DBP absorption of the porous carrier. Too low a loading may
lead, depending on the pore structure of the carrier
material, to an impairment in the effect of the protection
system. Too high an amount of protection system can have a
disadvantageous effect on the targeted deactivation and/or
is economically ineffective since as much active ingredient
as possible and as little protective substance as possible
should be absorbed.
In the present invention, active ingredients are understood
as meaning chemical compounds or natural substances which
have such a high solubility and/or reactivity and/or
instability under the preprocessing, storage and/or
application conditions that they cannot be mixed with other
components of the end formulation without suitable
protective measures and/or stored and/or transported to the
site of action, i.e. the site at which their reactivity is
to be unfolded and/or fixed at the site of action until the
desired release time. They may, however, also be chemical
substances which are viscous and not very flowable and

consequently have to be made flowable through absorption on
a carrier material, although desorption from the carrier
material must take place rapidly and completely as far as
possible, preferably exclusively, at a certain time. The
active ingredients can in principle be present as liquid,
oil, resin, solution, dispersion, suspension or as melt.
The only prerequisite is that the active ingredient can
penetrate into the pores of the carrier material.
The preferred active ingredients include, inter alia,
hardening agents or initiators, crosslinking agents,
catalysts, pharmaceutical active ingredients, cosmetic
active ingredients, cleaning and/or care agents,
flavorings, aroma substances or fragrances, feeds or feed
additives, such as, for example, amino acids, vitamins,
mineral substances, foods or food additives, dyes and/or
pigments, amino acids, oxidizing agents or bleaches,
additives with microbiocidal, in particular fungicidal or
bactericidal, effect, agrochemicals and/or a concrete
additive.
These include, inter alia, fragrances; oils such as
essential oils, perfume oils, care oils, scented oils and
silicone oils; antibacterial, antiviral or fungicidal
active ingredients; disinfectant and antimicrobial
substances; deodorants; antioxidants; biologically
effective substances and biogenetic active ingredients;
vitamins and vitamin complexes; enzymes and enzymatic
systems such as amalyses, celluloses, lipases and
proteases; cosmetically active substances such as
ingredients for cosmetics and body care compositions;
washing- and cleaning-active substances such as surfactants
of all types, washing- and/or cleaning-active inorganic and
organic acids, soil repellent and soil release active
ingredients, oxidizing agents and bleaches, bleach
activators, builders and cobuilders, antiredeposition
additives, graying and discoloration inhibitors, active

substances for color protection, substances and additives
for caring for laundry, optical brighteners, foam
inhibitors, pH extenders and pH buffer substances; UV
protective substances, UV absorbers, fluorescent and
phosphorescent agents; dyes, dye compositions, color
pigments and other coloring substances such as
solvatochromes and indicator dyes, initiators and
hardeners; catalysts and pharmaceuticals of all types; and
mixtures of the aforementioned compounds.
The product systems according to the invention can comprise
fragrances, aroma substances and odorants. Such substances
are generally known and commercially available. Suitable
fragrances are described, for example, in U.S. 5,500,138.
As used herein, fragrances encompass natural (i.e.
substances obtained for example by extraction from plants,
such as, for example, flowers, foliage, leaves, roots,
barks, woods, blossoms etc., or animal products), synthetic
(i.e. a mixture of different natural oils or oil
constituents) and synthetic (i.e. synthetically produced)
pleasant-smelling substances or mixtures of these
substances. Such materials are often used together with
further compounds, such as fixing agents, extenders, -
stabilizers and solvents. Within the context of the present
invention, these auxiliaries or additives are encompassed
by the meaning of the term "fragrance". Usually, therefore,
fragrances are complex mixtures of a large number of
organic compounds.
Natural compounds include not only readily volatile
substances; these also include medium-volatility and
moderate-volatility substances. An exemplary list of
fragrances includes, inter alia, the following compounds:-
Natural substances, such as tree moss absolute, basil oil,
citrus fruit oils (such as bergamot oil, mandarin oil,
etc.), mastix absolute, myrtle oil, palmarosa oil, oils

from the patchouli plant, petitgrain oil, in particular
from Paraguay, wormwood oil; alcohols, such as farnesol,
geraniol, linalool, nerol, phenylethyl alcohol, rhodinol,
cinnamyl alcohol; aldehydes,, such as citral, helional,
a-hexylcinnamylaldehyde, hydroxycitronellal, lilial (p-
tert-butyl-α-methyldihydrozimtaldehyde), methylnonyl-
acetaldehyde; ketones, such as allylionone (1-(2,6,6-
trimethyl-2-cyclohexen-1-yl)-1,6-heptadien-3-one),
α-ionone, β-ionone, isomethyl-alpha-ionone, methylionone;
esters, such as allyl phenoxyacetate, benzyl salicylate,
cinnamyl propionate, citronellyl acetate, citronellyl
ethoxolate, decyl acetate, dimethylbenzylcarbinyl acetate,
dimethylbenzylcarbinyl butyrate, ethyl acetoacetate, ethyl
acetylacetate, hexenyl isobutyrate, linalyl acetate, methyl
dihydrojasmonate, styrallyl acetate, vetiveryl acetate,
etc.; lactones, such as gamma-undecalactone; various
constituents which are often used for producing perfumes,
such as musk ketone, indole, p-menthane-8-thiol-3-one and
methyleugenol; and acetals and ketals, such as methyl and
ethyl acetals and ketals, and also the acetals or ketals
which are based on benzaldehyde, which contain phenylethyl
groups, or acetals and ketals of oxotetralins or oxoindanes
(cf. US-A-5,084,440).
Furthermore, fragrances which can be used according to the
invention include geranyl acetate, dihydromyrcenyl acetate
(2,6-dimethyloct-7-en-2-yl acetate), terpinyl acetate,
tricyclodecenyl acetate (CAS 5413-60-5), tricyclodecenyl
propionate (CAS 17511-60-3), 2-phenylethyl acetate, benzyl
acetate, benzyl benzoate, styrallyl acetate, amyl
salicylate, phenoxyethyl isobutyrate, neryl acetate,
trichloromethyl phenylcarbinylacetate, p-tert-butyl-
cyclohexyl acetate, isononyl acetate, cedryl acetate,
benzyl alcohol, tetrahydrolinalool, citronellol,
dimethylbenzylcarbinol, dihydromyrcenol,
tetrahydromyrcenol, terpineol, eugenol, vetiverol, 3-
isocamphylcyclohexanol, 2-methyl-3-(p-tert-butyl-

phenyl)propanol, 2-methyl-3-(p-isopropylphenyl)propanol,
3-(p-tert-butylphenyl)propanol, a-n-amylcinnamylaldehyde,
4-(4-hydroxy-4-methylpentyl)-3-cyclohexenecarbaldehyde,
4-(4-methyl-3-pentenyl)-3-cyclohexenecarbaldehyde,
4-acetoxy-3-pentyltetrahydropyran, 2-n-heptyl-
cyclopentanone, 3-methyl-2-pentylcyclopentanone, n-decanal,
n-dodecanal, hydroxycitronellal, phenylacetaldehyde
dimethylacetal, phenylacetaldehyde diethylacetal,
geranonitrile, citronellonitrile, cedryl methyl ether,
isolongifolanone, aubeplne nitrile, aubepine, heliotropin,
coumarin, vanillin, diphenyl oxide, ionone, methylionone,
isomethylionone, cis-3-hexenol and cis-3-hexenol ester,
musk compounds, which may have inter alia an indane,
tetralin or isochromane structure, macrocyclic ketones,
macrolactone-musk compounds, ethylene brassylate, aromatic
nitromusk compounds. Said fragrances can be used
individually or as a mixture.
The aroma substances which can be used for use as active
ingredient include wintergreen oil, oregano oil, laurel
leaf oil, peppermint oil, mint oil, clove oil, sage oil,
sassafras oils, lemon oil, orange oil, anise oil,
benzaldehyde, bitter almond oil, camphor, cedar leaf oil,
marjoram oil, lemon grass oil, lavender oil, mustard oil,
pine oil, pine needle oil, rosemary oil, thyme oil,
cinnamon leaf oil, and mixtures of these substances.
Organic and/or inorganic pigments can be used as active
ingredient. Furthermore, within the context of the present
invention, the term "pigment" includes materials which
bring about a weakening of color or shine, such as
substances which lead to a matting of surfaces or
scattering of light. Examples of the pigments that can be
used are iron oxides, ultramarine blue, D & C dyes, carmine
and mixtures of these substances. The pigments may be
treated. The treatment agents include, for example, amino
acids, silicones, and lecithin and ester oils.

Enzymes which can be used as active ingredients include,
inter alia, bacterial and fungus-like cellulases such as
Carezyme and Celluzyme (Novo Nordisk A/S); peroxidases;
lipases such as Amano-P (Amano Pharmaceutical Co.), Ml
Lipase® and Lipomax® (Gist-Brocades) and Lipolase® and
Lipolase Ultra® (Novo); cutinases; proteases, such as, for
example, Esperase® , Alcalase® , Durazym® and Savinase®
(Novo) and Maxatase® , Maxacal® , Properase® and Maxapem®
(Gist-Brocades); and α- and β-amylases such as Purafect Ox
Am® (Genencor) and Termamyl®, Ban® , Fungamyl® , Duramyl®
and Natalase® (Novo); and mixtures of these enzymes with
one another and also with other active ingredients.
Cosmetic active ingredients, in particular as constituent
of skin and hair cosmetics, include inter alia vitamins and
various lipophilic or hydrophobic substances which have a
moisturizing effect or an emollient effect, in particular
liquids, gels, waxes, particulate solids, etc. Lipophilic
or hydrophobic substances that can be used include inter
alia fatty acids such as lauric acid and oleic acid; esters
of fatty alcohols or fatty acids, such as isopropyl
myristate and isopropyl palmitate; water-insoluble ethers
and alcohols, such as lauryl alcohol, hexadecyl alcohol and
oleyl alcohol, paraffins and mineral oils, silicones and
mixtures of these compounds with one another and also with
other active ingredients. These materials are described
inter alia in the documents US-A4,053,851, US-A-4,065,564,
US-A-4,073,880, US-A-4,278,655 and GB-A-2,018,590.
These substances include in particular also compounds which
are used in connection with hair cosmetic applications,
such as alkali compounds, in particular NaOH, KOH, which
are used in particular for producing permanent waves.
The oxidizing agents and bleaches include, inter alia,
compounds which release chlorine or oxygen, such as, for
example, hydrogen peroxide, inorganic peroxides or organic
peroxides.

Inorganic peroxides include, inter alia, perborates,
percarbonates, perphosphates, persulfates and persilicates,
it being possible to use in particular the alkali metal
salts.
Sodium perborate can be used, for example, in the form of
the monohydrate of empirical formula NaB02H202 or the
tetrahydrate according to the empirical formula
NaB02H202*3H20. Alkali metal percarbonates, in particular
sodium percarbonate, are often complexes of alkali metal
carbonate and hydrogen peroxide. For example, sodium
percarbonate is understood as meaning a complex compound
with the empirical formula 2Na2C03*3H202, this being
commercially available. Potassium peroxymonopersulfate can
likewise be used as bleaching or oxidizing agent.
Organic peroxides include, for example, arylperoxy-acids,
such as, for example, perbenzoic acid, alkylperoxy acids,
such as, for example, peracetic acid and pernonanoic acid,
cationic peroxy acids and amide-substituted peroxy acids,
which are described, for example, in EP-A-0 170 386.
Further organic peroxy acids include diacyl and tetraacyl
peroxides, for example diperoxydodecanoic acid,
diperoxytetradecanoic acid and diperoxyhexadecanoic acid.
Dibenzoyl peroxide belongs to the preferred organic peroxy
acids. Mono- and diperazelaic acid, mono- and dipererucaic
acid and N-phthaloylaminoperoxicapronoic acid are likewise
suitable.
Moreover, hardeners and/or initiators represent an
important class of active ingredients. These compounds can
be used inter alia in adhesives and in construction
chemicals.
The substances include in particular radical starters,
which are used in a large number of applications. These
initiators include inter alia the azo initiators known
widely in the specialist field, such as AIBN and

1,1-azobiscyclohexanecarbonitrile, and also peroxy
compounds, such as methyl ethyl ketone peroxide,
acetylacetone peroxide, dilauryl peroxide, tert-butyl per-
2-ethylhexanoate, ketone peroxide, tert-butyl peroctoate,
methyl isobutyl ketone peroxide, cyclohexanone peroxide,
dibenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl
peroxyisopropylcarbonate, 2,5-bis(2-ethylhexanoylperoxy)-
2,5-dimethylhexane, tert-butyl peroxy-2-ethylhexanoate,
tert-butyl peroxy-3,5,5-trimethylhexanoate, dicumyl
peroxide, 1,1-bis(tert-butylperoxy)cyclohexane,
1,1-bis(tert-butylperoxy)-3,3,5-trimethylcyclohexane, cumyl
hydroperoxide, tert-butyl hydroperoxide,
bis(4-tert-butylcyclohexyl) peroxydicarbonate, mixtures of
two or more of the aforementioned compounds with one
another, and also mixtures of the aforementioned compounds
with unspecified compounds which can likewise form
radicals.
A further class of active ingredients is catalysts.
Catalysts are used to increase the rate of a large number
of different chemical reactions. The present invention
permits in particular the very specific use of catalysts at
a certain time, where a particularly uniform distribution
of the catalyst in the reaction mixture even at the start
of the reaction is possible.
The preferred catalysts include in particular metal-
containing catalysts which are used for hydrogenation, for
example for the hardening of fatty acids, nitriles and
polyol hydrogenation, hydrogenation of resins, aromatics
and white oils; selective hydrogenation of acetylenes and
dienes, and also selective hydrogenation of AMS to cumene.
Furthermore, these include catalysts which are used for
oxidation, for example for selective oxidation in the
production of ethylene oxide and vinyl acetate monomers.

These catalysts generally include metals, for example
nickel, cobalt, copper, molybdenum, chromium, iron, and
also platinum metals, for example rhodium, palladium,
platinum. Catalysts of this type are known per se and
described, for example, in Rompp Chemie Lexikon 2nd edition
on CD-ROM, and also Ullmann's Encyclopedia of Industrial
Chemistry, 5th edition on CD-ROM.
Moreover, the product systems can comprise active
ingredients which can be used in agriculture. These
include, for example, herbicides, fungicides, antibiotics,
fertilizers and feed additives, for example vitamins,
mineral substances and hormones, and also veterinary
medicine pharmaceuticals, for example antibiotics and
vaccines.
Furthermore, pharmaceuticals are a class of active
ingredients which may likewise be present as active
ingredient in the product systems according to the
invention. Pharmaceuticals are generally understood as
meaning a substance which exhibits in vivo a desired
effect, in particular a therapeutic effect. Accordingly,
pharmaceuticals are in particular substances which can be
used for the treatment of diseases or for achieving another
biological effect. A pharmacologically active substance can
accordingly be an organic or inorganic compound, and also a
living or dead organism. These include, inter alia,
proteins, polypeptides, polysaccharides (e.g. heparin),
oligosaccharides, mono- or disaccharides, organic
compounds, organometallic or inorganic compounds which can
include any known element; living or dead cells, bacteria,
viruses or one part thereof; hormones; growth factors, for
example virus-producing growth factor; growth factor
inhibitors, growth factor receptors, receptors or receptor
blockers (e.g. a 11a/111b inhibitor) or a complete or
partial gene in a suitable expression vector or construct
thereof for the local generation of therapeutic agents.

Pharmaceuticals include agents which are used for long-term
treatment, such as hormone treatments, for example for
preventing conception, and substances which are
particularly expedient for the treatment of diseases such
as osteoporosis, cancer, epilepsy, Parkinson's disease and
pain. The pharmaceuticals which can be used may be e.g.
anti-inflammatory agents, agents for fighting infectious
diseases (e.g. antibiotics and antivirals), analgesics and
analgesic combinations, agents for the treatment of asthma,
anticonvulsants, restoratives, agents for the treatment of
diabetes, antitumor agents, anticancer agents and agents
which are used for the treatment of cardiac vessel diseases
or mental illnesses, for example depression.
According to one particular aspect of the present
invention, as active ingredient, it is possible to use
compounds which preferably have a molecular weight of at
most 2000 g/mol, particularly preferably at most
1000 g/mol.
The product .system of the present invention can comprise
one or more active ingredients. Here, the active
ingredients may be present within the porous carrier as a
homogeneous mixture. Furthermore, the active ingredients
can also be arranged in layer form within the porous
carrier, in which case the porous carrier can have two,
three or more layers which may differ from one another in
terms of type and composition of the active ingredients.
Within the context of the present invention, protection
system is understood as meaning a substance/a combination
of two or more substances which prevents/prevent the active
ingredient decomposing and/or reacting prematurely and/or
being undesirably able to escape from the carrier material,
but at the same time also allows/allow the active
ingredient to be released as rapidly and completely as
possible following targeted deactivation of the protection
system.

The protection system is incorporated largely, i.e.
preferably to at least 30% by weight, particularly
preferably to 50% by weight, very particularly preferably
to 70% by weight - in each case based on the amount of
active ingredient used - in the pores of the carrier
material impregnated beforehand with active ingredient,
such that an active ingredient layer, which is arranged
closer to the core of the carrier material, and a
protective layer, which is arranged facing toward the outer
surface of the carrier material, are formed in the pores.
The active ingredient is thus shielded from influences in
the surrounding area. For example, it can be assumed that
the pores of the inorganic porous carrier, which has been
partially provided with active ingredient, are closed by
the protective compound. Following partial breakup or
partial destruction of this closure of the pores, the
active ingredient can be released.
The term "protection system" was chosen to make it clear
that the present invention does not use a customary coating
in order to achieve controlled release of active
ingredients. Rather, the system is designed such that a
high mechanical stability is associated with a very
specific release mechanism.
In order to be able to construct an effective protection
system, it is advantageous if active ingredient and
protection system have a different polarity or a different
solubility or dispersibility so that they do not mix with
one another. In this connection, the terms "soluble or
dispersible" mean that at least 1 g/1, preferably at least
10 g/1 and particularly preferably at least 100 g/1, of a
substance can be broken up or dispersed in a corresponding
solvent. Substances are insoluble if less than 1.0 g/1,
preferably at most 0.5 g/1 and particularly preferably at
most 0.05 g/1, of a substance can be broken up or
dispersed. These values refer to the temperature at which

the loading of the carrier with the active ingredient
and/or the protection system takes place. Preferably, the
solubility is measured in a temperature range from 0°C to
100oC, particularly preferably 25°C.
It may thus be advantageous if the protection system
comprises at least one compound which is soluble in a
solvent in which the active ingredient does not break up.
Particularly preferably, the active ingredient is soluble
in a polar solvent and the protective layer is insoluble in
water and/or in a polar solvent, or the active ingredient
is soluble in a nonpolar solvent and the protection system
is insoluble in this nonpolar solvent and/or soluble in a
polar solvent and/or water. Suitable nonpolar solvents here
are in particular aromatic hydrocarbons, alkanes or a
cycloalkane. By virtue of the different
polarity/solubility, it can be ensured that the active
ingredient and protection system within the pores do not
mix, but form clearly separate layers, such that effective
deactivation of the protective layer is possible.
According to one particular aspect of the present
invention, the active ingredient can be broken up in a
polar solvent, for example water, methanol and/or ethanol,
whereas the protective layer is insoluble in water. These
active ingredients include in particular water-soluble
oxides and/or hydroxides, such as, for example NaOH or KOH.
Preferably, the protection system according to this aspect
has at least one compound which is soluble in a nonpolar
solvent, particularly preferably an aromatic solvent, such
as toluene, an alkane, in particular hexane or heptane, or
a cycloalkane, such as cyclohexane.
The protection system for the active ingredient/active
ingredients is preferably designed in such a way that by
deactivating the protection system through an input of
energy and/or chemical conversion and/or breakup of the
protection system, the protection system is changed in such

a way that, preferably spontaneously, at least 50% of the
active ingredient/active ingredients is/are released.
The selection of the protective material depends primarily
on the release conditions. Thus, for example, the release
of a radical starter in a chemical reactor may be the aim.
Here, the deactivation of the protection system via
pressure waves may be the method choice since this is
possible very rapidly and effectively. If, for example, a
radical quencher is to be added to a radical chain
reaction, but can only then come into contact with the
other reactants, if the reaction temperature has exceeded a
certain limit - in order to prevent a "run away" of the
reaction - then the protection system to be used would be a
substance which releases the active ingredient upon
reaching a certain temperature. Through suitable selection
of the protection system, it is thus possible to produce a
product system with high latency and storage stability for
highly diverse application purposes. A further example is
hygroscopic cosmetic and/or pharmaceutical active
ingredients which are to be absorbed by the human skin. In
order to be storage-stable, these substances have to be
protected by a protection system and are only released
again upon contact with the skin, but then rapidly and
completely. For this application, a pH-sensitive protection
system is the choice. The aforementioned examples in no way
limit the scope of the present invention, but merely serve
to explain and clarify the present invention.
In the case of deactivation of the protection system by
inputting energy, the energy input preferably takes place
by pressure waves, particularly preferably by ultrasound
treatment, irradiation with high-energy radiation,
preferably UV light and microwaves and/or by the action of
artificially generated shear forces and/or temperature
increase. Under the influence of the pressure waves (in
particular ultrasound treatment), the particulate systems

are "ruptured", because the porous carrier body and the
active ingredients and protection systems stored in the
pores oscillate under the influence of the pressure waves
and/or cavitation at different frequencies (on account of
different mechanical properties). The particles break apart
and open up to the outside medium access to the no longer
protected active ingredient. In the case of release by
increasing the temperature, transportation of the active
ingredient to the outside is ensured by the melting and/or
by the increased rate of breakup of the protection system
in the outside medium. In the case of release as a result
of UV light or as a result of X-ray irradiation, the
protection system is "deactivated" or "opened" by the
radiation-based chemical reaction, which is often
associated with the temperature increase up to the melting
point. In the case of release due to microwaves, part of
the encapsulated system is heated locally until the
formation of the vapor phase, the internal pressure within
the particle increases and leads, as in the case of the
release under ultrasound, to the rupture of the particles
and opening of the active ingredient. Another variant of
the release through the action of microwaves is the local
heating of the encapsulation system up to the melting of
the protection system and subsequent opening of the access
of the outside medium to the active ingredient.
If pressure waves, preferably ultrasound waves are allowed
to act on the product system, then, in one particular
embodiment of the present invention, at least 80% by weight
of the active ingredient/active ingredients are released
within 1 hour, preferably at least 80% by weight in
10 minutes, very particularly preferably at least 80% by
weight in 5 minutes, especially preferably at least 80% by
weight in 1 minute or less. Here, the protection system can
be constructed such that it is broken up at a pregiven
stress value. This can take place, for example, as a result
of the targeted selection of the material and also the

amount of protection system based on the total weight of
the product. The pressure waves can be adjusted by varying
the frequency and the amplitude to a pregiven stress value
at which breakup of the protection system takes place.
Preferably, the pressure waves can have a frequency in the
range from 15 kHz to 100 kHz, particularly preferably in
the range from 22 kHz to 30 kHz and an amplitude in the
range from 0 to 250 urn, particularly preferably in the
range from 40 urn to 100 urn.
If, on the other hand, high-energy radiation is allowed to
act on the product system, then, in a further particular
embodiment of the present invention, at least 80% by weight
of the active ingredient/active ingredients are released
over the course of 12 hours, preferably at least 80% by
weight in 10 hours, very particularly preferably at least
80% by weight in 5 hours, especially preferably at least '
80% by weight in 1 hour or less.
Examples of radiation-sensitive protection systems are, for
example, all water-containing protection systems which can
be heated locally in a targeted manner through the
application of microwave technology. Preferably, the
electromagnetic radiation can have a frequency in the range
from 1 MHz to 500 GHz, particularly preferably in ranges
from 902 MHz to 928 MHz and 2.4 GHz to 2.5 GHz. The
electromagnetic radiation can also be adapted to other
components of the system. Thus, for example, when using
mixed oxides of the type MagSilica® (Evonik Industries AG)
as carrier or as constituent of the protection system, the
electromagnetic radiation with a frequency in the range
from 280 MHz to 320 MHz is particularly preferred.
If, by contrast, the deactivation of the protection system
takes place on reaching a certain release temperature,
then, in a further particular embodiment of the present
invention, at least 60% by weight of the active
ingredient/active ingredients are released over the course

of 60 minutes, preferably at least 80% by weight in
60 minutes, very particularly preferably at least 80% by
weight in 45 minutes, especially preferably at least 80% by
weight in 30 minutes or less. In this case, the protective
layer is broken up or melted by increasing the temperature,
as a result of which the active ingredient is released.
According to this aspect of the present invention, the
protection system can be broken up preferably by a
temperature in the range from 30 to 200°C, particularly
preferably 40°C to 160°C. Here, the protective layer is
preferably destroyed within a narrow temperature interval.
Thus, the temperature interval at which the protection
system is broken up or melted can be less than 20°C,
preferably less than 10°C and very particularly preferably
less than 5°C.
Chemical deactivation of the protection system can be
triggered, for example, by a shift in pH and/or the action
of at least one enzyme on the protection system.
If the deactivation takes place by changing the pH of the
protection system, then, in a further particular embodiment
of the present invention, at least 70% by weight of the
active ingredient/active ingredients are released over the
course of 8 hours, preferably at least 80% by weight in
8 hours, very particularly preferably at 80% by weight in
5 hours, especially preferably at least 70% by weight in
1 hour or less.
Examples of pH-sensitive protection systems are, for
example, a copolymer of methyl methacrylate and ethyl
acrylate (Eudragit L 100-55/L, Acryl EZE, Eastacryl 30D), a
copolymer of methyl methacrylate and ethyl acrylate and
methacrylic acid, a (meth)acrylate copolymer consisting of
20 - 40% by weight of methyl methacrylate and 60 to 80% by
weight of methacrylic acid (Eudragit L 100/L, S 100/S and
further modifications of the Eudragit0 product group), a
copolymer of methyl methacylate, ethyl acrylate and

trimethylammonium ethyl methacrylate, a polyvinyl acetate
phthalate (PVAP, Coateric® , Sureteric® ), a crosslinked
and/or uncrosslinked polyacrylic acid,
hydroxypropylmethylcellulose phthalate (H.P.M.C.P.
(Eastman), HP (Shin-Etsu)), hydroxymehylethylcellulose
(HEMC), ethylcellulose (EC, Ethocel® , Aquacoat® ,
Surelease® ), cellulose acetate phthalate (CAP, Cellulosi
acetas, PhEur, Celluloseacetate-Phtalate, NF, Aquateric® ),
cellulose acetate succinate (CAS), cellulose acetate
trimeliate (CAT), hydroxypropylmethylcellulose phthalate
(HPMCP, HP50, HP55), hydroxypropylmethylcellulose acetate
succinate (HPMCAS -LF, -MF, -HF) or a mixture of said
polymers, fatty acids (e.g. stearic acid, palmitic acid)
and a mixture of the fatty acids, further polymeric acids,
for example polyacrylates which are characterized by the
required solubilities as a function of pH on the one hand,
and by good processability on the other hand. Further
polymeric acids which can be used as coating materials are
copolymers of an unsaturated polycarboxylic acid such as
maleic acid, citraconic acid, itaconic acid and mesaconic
acid with an unsaturated monocarboxylic acid such as
acrylic acid or α-alkyl-substituted acrylic acids.
In the case of the action of enzymes on the protection
system, in a further particular embodiment of the present
invention, at least 80% by weight of the active
ingredient/active ingredients are released over the course
of 24 h, preferably at least 80% by weight in 15 hours,
very particularly preferably at least 80% by weight in
10 hours or less.
Examples of biologically/enzymatically deactivatable
protection systems are the natural, semisynthetic or
synthetic, inorganic and in particular organic materials
known in the prior art, provided it is ensured that the
enzymatic-controlled opening of the resulting mixtures is
retained.

Natural organic materials are, for example, homopolymers
and heteropolymers of carbohydrates, amino acids, nucleic
acids, amides, glucosamines, esters, gum Arabic, agar agar,
agarose, maltodextrins, alginic acid or its salts, e.g.
sodium or calcium alginate, liposomes, fats and fatty
acids, cetyl alcohol, collagen, chitosan, lecithins,
gelatin, albumin, schellack, polysaccarides, such as starch
or dextran, cyclodextrins, sucrose and waxes.
Semisynthetic encapsulation materials are, inter alia,
chemically modified celluloses, in particular cellulose
esters and ethers, e.g. cellulose acetate, ethylcellulose,
hydroxypropylcellulose, hydroxypropylmethylcellulose and
carboxymethylcellulose, and also starch derivatives, in
particular starch ethers and esters.
Synthetic encapsulation materials are, for example,
polymers such as amino resins, polyacrylates, polyamides,
polyvinyl alcohol or polyvinyl pyrrolidone, organopolysi-
loxanes, non-natural amino acids, non-natural nucleic
acids, polyamines, polyols, oligo- and polyisoprenes,
esters and polyesters, in particular branched glycerol
ester amides, imines, polyphenols, dithiols and
phosphodiesters, ethylene glycol, oxymethylene glycoside,
acetal units, silicates and carbonates, hyperbranched
hydrogels, comb polymers with polyester structure or
polyvinyl ppyrrolidone, polylactide.
Further preferred carrier polymers that can be co-used are
polycaprolactones, copolymers such as poly(D,L-lactide-co-
glycolide) and also the polyester compounds from the
product families DynapoKSS and Dynacoll® produced by
Evonik Industries AG. These polymers can also serve as
admixture for establishing specific polymer properties.
By admixing these polyesters, the composition of the
polymer can be adjusted such that the resulting
encapsulation material can be degraded enzymatically over a

short or long time. Further biologically or enzymatically
deactivatable protection systems such as hyperbranched
polymers are described in detail in the patent application
WO 2007/048464.
Furthermore, it is possible to achieve deactivation of the
protection system by breaking up the protection system in a
suitable solvent. Here, the product system is placed in the
suitable solvent or in a two-phase system with two
solvents, one of which breaks up the protection system and
the other of which breaks up the active ingredient, and,
preferably within 24 hours, at least 80% by weight of the
active ingredient/active ingredients are released,
preferably at least 80% by weight in 15 hours, very
particularly preferably at least 80% by weight in 10 hours.
Examples of such protection -systems are inorganic (e.g.
Na2SO4) and inorganic (e.g. sodium stearate) salts, organic
acids (e.g. stearic acid, palmitic acid), polymers (such as
polyethylene glycol, polyvinyl chloride), copolymers,
alcohols (in particular fatty alcohols), and further
chemical substances which are soluble under given release
conditions (temperature, pressure, composition) in a
solvent present at the site of release.
The product systems according to the invention exhibit
excellent latency. Latency means that the product systems
release no or only minimal amounts of active ingredient
during their production, storage and transportation. Even
upon the incorporation of the product systems according to
the invention into premix formulations and their subsequent
storage, no or only minimal amounts of active ingredient is
released for a length of time until activation of the
product systems according to the invention takes place,
i.e. until the release of active ingredient is triggered as
a result of the input of energy or chemical influences.

As already indicated above, the product system according to
the invention permits tailored solutions to be created for
a large number of application cases. Thus, for example, it
is possible to produce mixtures of two or more product
systems according to the invention which comprise identical
or different active ingredients and different protective
substances. For example, these mixtures make it possible,,
upon reaching a certain temperature, for 20% by weight of
the active ingredient to be spontaneously released, from
formulations with temperature-sensitive protective layer
and active ingredient underneath, but the remaining 80% by
weight of the active ingredient to be released constantly
over a prolonged period from a second product system with
temperature-sensitive protective layer and active
ingredient embedded underneath in a diffusion-open matrix.
Another example would be a mixture of product systems, of
which one part of the active ingredient is released after
changing the pH, but another part is only released after
the action of ultrasound. Possible combinations of active
ingredient/protection systems and breakup mechanisms can be
derived easily by reference to the above description and
form part of the present invention even if they are not
described explicitly. In a further example, the protective
compound can have a very specific melting point. If the
product system is heated to temperatures above this melting
point, then the active ingredient is released since the
protective compound is melted. This mechanism can be used
for example in the field of hardeners or initiators.
Furthermore, this mechanism can be used for the field of
hair cosmetics.
A further very specific example of product systems
according to the invention is configured such that the
active ingredient is latent, i.e. is released only after a
certain time, but then uniformly over a prolonged period.
For this, for example, an active ingredient can be
introduced into the carrier material together with the

matrix material and then a protective layer according to
the invention can be applied. After deactivating the
protective layer, the release of the active ingredient then
takes place from the matrix material in a diffusion-
controlled manner such that uniform release over a
prolonged period is ensured.
Suitable compounds for producing the protection system,
subsequently also called "protective compounds", are
generally known, it being possible to select the particular
compound for producing this system according to the
intended use and field of application of the product
system.
For example, the protective compound can be a law molecular
weight, oligomeric or polymeric compound. These include,
for example, hydrophilic or polar polymers, in particular
polysaccharides, for example cellulose, cellulose
derivatives, such as cellulose acetate, methylcellulose,
carboxymethylcellulose, crosslinked and uncrosslinked
hydroxypropylcellulose, crosslinked and uncrosslinked
polyhydroxypropylmethylcellulose, starch or starch
derivatives, for example hydroxyalkyl starch, carboxymethyl
starch, crosslinked and uncrosslinked sodium cellulose
xanthogenates, polyvinyl alcohols, polymethacrylates,. in
particular polymethyl methacrylates,
methacylate/divinylbenzene copolymers, potassium
methacrylates/divinylbenzene copolymers,
carboxymethylamide, polyoxyalkylene glycols, crosslinked
and uncrosslinked polyvinylpyrrolidones, polyoxyethylene
glycols and polyvinyl alcohols.
Furthermore, at least one low molecular weight, hydrophilic
compound can be used for producing the protection system.
Furthermore, the protective compound may be a hydrophobic
substance. These include, among alkylcellulose polymers
which can be used in the form of latex suspensions, such

as, for example, Surelease® (Colorcon GmbH, Germany), or
cellulose acetate phthalate (Aquacoat® CPD; FMC, Germany)
or methacrylic acid derivatives which can be used inter
alia in the form of suspensions such as Eudragit® RS, RL
and NE (Rohm Pharma, Germany).
Moreover, waxes can also be used as protective compound.
These include, inter alia, nonionic beeswax derivatives
such as Gelucire® 62/05, 50/02 or 50/13 (Gattefosse
Deutschland, Germany), glycerol behenate, or other fatty
acid mono-, di- or triesters of glycerol such as Precirol®
ato 5 (Gattefosse Deutschland, Germany), microcrystalline
wax, hydrogenated castor oil or hydrogenated vegetable oil,
long-chain aliphatic alcohols, such as stearyl alcohol and
carnuba wax.
Furthermore, polyolefins or paraffins may be suitable
compounds for producing a protection system. Particularly
suitable products are available under the name Sasol Wax® ,
which can be obtained from SasolTM, where in particular
mention is to be made of the grades Sasol Wax® 5403, Sasol
Wax® 5413, Sasol Wax® 5603 and Sasol Wax® 4110P.
Protective compounds which exhibit pH dependency include
polymers such as, for example, polymethacrylic acid
derivatives which can be used in the form of latex
suspensions, such as Eudragit® L and S (Rohm Pharma,
Germany), Aquacoat® CPD, hydroxypropanol methylcellulose
phthalate (HPMCP), polyvinyl acetate phthalate,
hydroxypropanol methylcellulose acetate succinate, shellac,
cellulose acetate trimellitate, carboxymethylcellulose,
copolymers of maleic acid and phthalic acid derivatives,
and also mixtures thereof.
Moreover, the protective compounds can in part comprise
acid-soluble constituents, for example in the form of the
polymers, in particular polyvinylpyrrolidone,
hydroxypropanolcellulose, hydroxypropanolmethylcellulose,

polyethylene glycol, polyvinyl alcohol, or in the form of
low molecular weight substances, sugars, salts or organic
acids and mixtures of these substances.
Furthermore, surfactants and/or emulsifiers can be used in
order to produce a protection system. These include in
particular carboxylic acids and carboxylic acid
derivatives, such as esters or amides of carboxylic acids
which have 6 to 40, preferably 8 to 30, carbon atoms in the
acid radical. Preferred carboxylic acids include, inter
alia, caprylic acid, capric acid, lauric acid, myristic
acid, palmitic acid, margaric acid, arachic acid, behenic
acid, lignoceric acid, cerotic acid, palmitoleic acid,
stearic acid, oleic acid, elaidic acid, petroselic acid,
ricinolic acid, elaeostearic acid, linolic acid, linolenic
acid, eicosanoic acid, gadoleic acid, docosanoic acid or
erucasic acid.
The protection system of the product according to the
invention can have one or more layers of protective
compounds. For example, a second protective compound can be
applied to the first protective compound. Moreover, the
composition of the protective compounds in a protection
system can be modified in order to obtain a layered
structure.
A particularly preferred protection system can have a
layered structure. Here, the layered protection system can
have, for example, a first layer, directed to the core,
which comprises a hydrophobic first protective compound,
for example a paraffin wax, and a second protective layer,
directed outwardly, which comprises e.g. a surfactant as
protective compound.
The product systems according to the invention can be
produced by introducing an active ingredient into a porous
carrier and producing a protection system.

Here, the following steps are preferably carried out
a) introduction as initial charge of at least one carrier
material in a solids mixing unit
b) optional evacuation of the solids mixing unit
c) optional preimpregnation of the carrier material with
at least one protective substance until at most 50% by
weight of the DBP absorption value is achieved
d) addition of at least one active ingredient to the
solids mixing unit
e) impregnation of the carrier with active ingredient
f) optional inhibition of the active ingredient adhering
to the outer particle surface of the carrier material
and/or washing and/or drying
g) addition of at least one protective substance
h) impregnation of the carrier with at least one
protective substance
i) optional washing and/or drying
j) optional reactive inhibition of the active ingredient
adhering to the external particle surface of the
carrier material and/or washing and/or drying.
The solids mixing unit used in step a) may be for example:
kneaders, paddle driers, tumble mixers, vertical mixers,
paddle mixers, Schugi mixers, cement mixers, Gericke
continuous mixers, Eirich mixers and/or silo mixers. The
temperature in the mixing unit is preferably between 5°C
and 250°C, particularly preferably between 60°C and 140°C,
depending on the protection system and the active
ingredient.

Step b) is optional, i.e. does not necessarily have to be
carried out. However, by evacuating the solids mixing unit
after adding the carrier material, the pores of the carrier
material can be evacuated and the gas or air present
therein can be drawn out, so that more complete loading of
the carrier material with active ingredient(s) and
protective substance(s) can be achieved.
Step c) is likewise optional and is carried out depending
on the pore structure of the carrier material. As already
stressed several times, it is important for the
effectiveness of the protection system according to the
invention that the pores are closed as completely as
possible with protective substances to the outside so that
the active ingredient is protected against contact with
solvents. In most porous carrier materials, the pores are
joined together in a more or less complex system.
Consequently, it is possible that narrow pores into which
neither active ingredient nor protective substance, e.g. on
account of the viscosity, can penetrate, but likely
solvents, inside of the carrier material, have a connection
to a pore into which the active ingredient has penetrated.
In this way, the case could arise that although the active
ingredient cannot be removed from the actual pore into
which it has soaked, as a result of the smaller "secondary
pores", solvent comes into contact with the active
ingredient inside of the carrier and thus some active
ingredient is nevertheless removed.' As a result of a .
preimpregnation of the carrier material with the protection
system, such undesired effects can be avoided since as a
result these "side channels" can be closed before the
active ingredient is absorbed. In particularly preferred
embodiments, protective substance is introduced in the form
of a solution or as melt.
In step d), the active ingredient or a plurality of active
ingredients is added to the solids mixing unit. If a

plurality of active ingredients is to be added, these can
be added simultaneously or in succession. The active
ingredients can, if liquid, be added directly, or are added
as melt or else also as solution or in the form of a
dispersion or a suspension.
In step e), the active ingredient/active ingredients are
introduced into the carrier material or the preimpregnated
carrier material. Here, the .mixing time/incorporation time
is designed such that complete penetration of the active
ingredients into the pores is ensured. Impregnation with an
active ingredient is terminated when the pourability of the
product measured using the flow funnels in accordance with
DIN 53492 has the value 1. In one particularly preferred
embodiment, the active ingredient is broken up in a
solvent, the solution is introduced into the carrier .and
the product obtained in this way is dried in order to
remove the solvent.
For many fields of application, it is important that the
active ingredients can actually only develop their effect
at a certain time, i.e. in such cases, no kind of active
ingredient must come into contact with a reactant
prematurely. However, since during the impregnation in step
e), i.e. during the soaking of the active ingredient into
the pores, it is usually not possible to prevent at least a
few active ingredient molecules adhering to the outer
carrier surface, it may, depending on the field of
application, be useful to inhibit these active ingredient
molecules in an optional step f) or to remove them from the
outer carrier surface by washing in order to ensure that
active ingredient is actually present only in the pores. In
the case of inhibition, active ingredient present on the
surface is reacted to give an unreactive substance by
virtue of a corresponding reactant. In the case of washing,
the active ingredient is washed away using a suitable
solvent. Depending on the active ingredient, several

washing operations are necessary. If the intention were to
introduce the active ingredient/active ingredients in the
form of a solution or suspension, then the solvent is
preferably removed prior to adding the protective
substance, preferably by evacuation or heating.
In step g), the protective substance or a plurality of
protective substances is added to the solids mixing unit.
If a plurality of protective substances are to be added,
these can be added simultaneously or in succession. The
protective substances can, if liquid, be added directly, or
be added as melt or else also as solution or in the form of
a dispersion or a suspension. In particularly preferred
embodiments, protective substance is introduced in the form
of a solution or as melt. In step h), it must be ensured
that the pores are filled as completely as possible since
the pores which lead from the surface to the core of .the
carrier particle are joined together by interpore channels
which transmit solvents and could thus bring about release
of the active ingredient.
If the protective substance/protective substances are to
have been added in the form of a solution or suspension,
then preferably the solvent is removed particularly
preferably by evacuation or heating.
In order to remove excess protective substance, it is
possible, where necessary, for a washing step with
subsequent drying to take place in step i).
Depending on the active ingredient and protection system,
it may be useful, instead of the inhibition or the washing
off of the active ingredient adhering to the outer carrier
surface in step f), to carry out this inhibition or this
washing operation after applying the protective layer, i.e.
in step j). As a rule, it will be more effective to carry
out the washing or inhibition in step j) instead of step f)
since in step g) the pores have been closed by the

protective substance and thus in step j) only the active
ingredient molecules adhering to the outer surface are
eliminated. It is also possible to wash and/or inhibit both
in step f) and also in step j). It is also possible both to
wash and also to inhibit in step f) and/or j}.
In specific cases, stages b) to e) and/or g) to h) are
carried out several times, in which case, upon repeating
steps d) and e) and/or g) and h), in each case identical or
different active ingredients and/or protective substances
can be used. In addition, it is advantageous to select the
protective substance or the active ingredient in steps c),
d), e), g) and h) the mixing conditions in such a way that
the active ingredient or protective substance always
remains liquid and does not dry out or crystallize out on
the surface of the particles.
In one particular embodiment of the method according to the
invention, step d) is not carried out after step a), but
before, i.e. the carrier material and the active
ingredient/active ingredients are mixed before they are
poured into the solids mixing unit. Particular advantages
in this case are-in the uniformity of the active ingredient
distribution within the carrier particles. This is very
important in the case of high active ingredient loading (in
particular in the range 60 to 80% of the DBP value) in
order then to be able to load all particles uniformly with
the protection system.
In a further particular variant of the method according to
the invention, a pretreatment of the carrier material with
surfactants or with silanes can take place before the
active ingredient and/or protection system is added. This
can lead firstly to a hydrophobization of the carrier, as a
result of which - depending on the polarity of the carrier,
it is possible that it is made easier for the active
ingredient(s) to penetrate deeply into the pores. Secondly,
as a result, however, it is also possible to achieve

closure of ultrafine pores, which is desirable since
undesired, rapid release of active ingredient can thereby
be prevented.
In principle, it is also possible to carry out steps c) and
d) simultaneously and to add a mixture of at least one
active ingredient and at least one protective substance.
This may be particularly useful if the protective substance
can penetrate into smaller pores than the active ingredient
and thus the effect described above, i.e. the "sealing" of
side pores is also possible in the event of simultaneous
incorporation of protective substance and active
ingredient.
In order to ensure the functionality of the product systems
according to the invention, in particular the mechanical
stability, it is necessary that firstly no active
ingredient is present on the carrier surface, but secondly
also that as far as possible no protective substance is
present on the outer carrier surface. Ideally, both
components should be completely soaked into the pores of
the carrier material. In order to achieve this, the added
amount of protective substance/protective substances in
step g) should be regulated such that the total amount of
active ingredient/active ingredients plus protective
substance/protective substances which is added during the
production of the product systems corresponds to 50% to
100% of the DBP absorption value (according to DIN 53601)
of the carrier material.
Alternatively, the production process can, however, also be
controlled via the pore volume; in this case, the added
amount of protective substance/protective substances .in
step g) is preferably regulated such that the total amount
of active ingredient/active ingredients and protective
substance/protective substances which is added during the
production of the product systems is greater than the total
pore volume of the carrier material and that the excess of

then this condition is satisfied.
Conventional methods in which a large amount of coating
composition is added rapidly to the carrier material have
the disadvantage that they may lead to gas inclusions in
the pores, i.e. that the pores are not filled as desired
with active ingredient, but with gas.
The present product systems can be used in many products.
These include in particular cosmetics, medicaments,
deodorants, foods, construction materials, agrochemicals,
adhesives, packagings and/or coating systems.
The present invention is explained in more detail below by
reference to examples, without any limitation being
intended as a result.

protective substance/protective substances is absorbed by
adding carrier material and/or carrier material laden with
active ingredient/active ingredients.
The mixing intensities and the dosage in the method
according to the invention should be matched to one another
such that pourability at the end of the application process
is ensured, i.e. that a pourable powder is present in the
mixer at any time. Consequently, it can be ensured that the
protective substance and/or active ingredient is completely
absorbed into the pores and does not adhere to the outer
carrier surface. If dosing is too rapid or if mixing is not
intensive enough, the result may be uneven loadings of the
particles, which can ultimately lead to the pores of some
particles being filled completely with active ingredient
and a protective substance can no longer penetrate in and
thus no latency can be achieved. In this connection, it
should also be ensured that the stirring elements, e.g. IKA
Duplex stirring element in the measurement kneader H60, are
chosen such that no abrasion takes place as a result of
shear stress. The checking for abrasion on the particles
takes place by measuring the particle size distribution.
For this, the carrier materials are introduced into the
mixing unit used subsequently and the mixing operation is
started corresponding to the subsequent procedure. After a
defined mixing time, samples are taken and the particle
size distribution is determined. For the particle size
distribution, the deviation from the d50 value of the
starting sample should not be greater than 5%. If, for
example, the result of the particle size distribution
before mixing is:
Average particle size d50 = 23.72 µm
and the result of the particle size distribution after
mixing is:
Average particle size d50 = 22.74 µm,

Measurement methods
Determination of the DBP number:
The DBP absorption (DBP number}, which is a measure of the
absorptivity of a porous carrier material is determined as
follows in accordance with the standard DIN 53601:
12.50 g of pulverant or spherical carrier material with
0 - 10% moisture content (if necessary the moisture content
is adjusted by drying at 105°C in the drying cabinet) are
added to the kneader chamber (article number 279061) of the
Brabender absorptometer "E" (without damping the starting
filter of the torque sensor). In the case of granules, the
sieve fraction from 3.15 to 1 mm (stainless steel sieve
from Retsch) is used (by gently pressing the granules
through the sieve with a pore width of 3.15 mm using a
plastic spatula). With continuous stirring (rotational
speed of the kneader blades 125 rpm), dibutyl phthalate is
added dropwise to the mixture at a rate of 4 ml/min at room
temperature through the "Dosimaten Brabender T 90/50".
Mixing in takes place only with low power consumption and
is monitored using the digital display. Toward the end of
the determination, the mixture becomes pasty, which is
indicated by means of a steep increase in the power
consumption. When 600 digits are displayed (torque of
0.6 Nm) both the kneader and also the DBP metering are
switched off via an electrical contact. The synchronous
motor for the introduction of DBP is coupled to a digital
counter so that the consumption of DBP can be read off in
ml.
The DBP absorption is given in the unit [g/(100g)] without
decimal places and calculated using the following formula:


where DBP = DBF absorption in g/(100g)
V = consumption of DBP in ml
D = density of DBP in g/ml (1.047 g/ml at 20°C)
E = initial weight of silica in g
K = correction factor according to moisture
correction table in g/(100g)
The DBP absorption is defined for the anhydrous, dried
carrier materials. When using moist carrier materials, in
particular precipitated silicas or silica gels, the
correction factor K should be taken into consideration for
calculating the DBP absorption. This value can be
ascertained by reference to the following correction table,
e.g. a water content of the carrier material of 5.8% would
mean an addition of 33 g/(100 g) for the DBP absorption.
The moisture of the carrier material is determined
according to the method described below "Determination of
the moisture and/or the drying loss".
Tabla 1: Moisture correction table for dibutyl phthalate .
absorption - anhydrous -



Determination of the moisture or of the drying loss
The moisture or else drying loss (TV) of carrier materials
is determined in accordance with ISO 787-2 after drying for
2 hours at 105°C. This drying loss consists predominantly
of water moisture.
Procedure
In a dry weighing glass with ground cover (diameter 8 cm,
height 3 cm), 10 g of the pulverant, spherical or granular
carrier material are weighed in to precisely 0.1 mg
(initial weight E). The sample is dried with an opened
cover for 2 h at 105 ± 2°C in a drying cabinet. The
weighing glass is then closed and cooled to room
temperature in a drying cabinet with silica gel as drying
agent.
The weighing glass/beaker is weighed precisely to 0.1 mg on
a precision balance in order to determine the final weight
A. The moisture (TV) is determined in % in accordance with

where A = final weight in g and E = initial weight in g.

Average particle size d50
The particle distribution of the product systems according
to the invention is determined by the principle of laser
diffraction on a laser diffrometer (Horiba, LA-920).
To determine the particle size of powders, a dispersion
with a weight fraction of ca. 1% by weight of SiO2 is
prepared by stirring the powder into water.
Directly after the dispersion, the particle size
distribution of a part sample of the dispersion is
determined using the laser diffrometer (Horiba LA-920). For
the measurement, a relative refractive index of 1.09 should
be chosen. All measurements are carried out at room
temperature. The particle size distribution and also the
relevant parameters e.g. the average particle size d50 are
automatically calculated and depicted graphically by the
instrument. The comments in the operating instruction
should be observed.
Investigating the surface composition by means of XPS
Measurement principle
Under ultrahigh vacuum conditions, a material surface is
bombarded with soft X-ray radiation (e.g. MgKa). This
detaches so-called photoelectrons, the kinetic energy of
which, after they have left the material surface, is
analyzed using an electron spectrometer (fig. 1).
When measuring a metallic sample which is in electrically
conductive contact with the spectrometer, then the
following applies for the kinetic energy of the detached
photoelectrons:

i.e. the energy of the irradiated X-ray radiation (hv)
minus the binding energy (EB) minus the work function of

the spectrometer (ΦSp'). In the case of electrically
nonconductive materials, contributions are additionally to
be taken into consideration.
From this balance between the excitation energy and the
measured kinetic energy it is thus possible to ascertain
the binding energy of the electrons to the sample atoms.
This depends directly on the chemical bonding state of the
elements. Thus, for example, for metallic platinum on a
carrier, a different value is measured than for di- or
tetravalent platinum. Sulfate-sulfur produces different
values to sulfide-sulfur or sulfane-sulfur and PMMA
produces different oxygen and carbon signals to
polycarbonate, polyoxymethylene or Teflon. A classic
example of an XPS result can be found in figure 2. It is
clear that even different bonding states of the carbon in
ethyl trifluoroacetate can be identified by reference to
the "chemical shift" of the C signals. By reference to the
so-called "chemical shift" of the XPS signals it is thus
possible to differentiate different bonded atoms from one
another, as a result of which it is possible to establish
how large the fraction of carrier atoms or active
ingredient atoms or protective substance atoms is on the -
surface of the product systems according to the invention.
On account of the possibility of being able to
differentiate differently bonded atoms from one another,
the name ""ESCA" (electron spectroscopy for chemical
analysis) was coined by K. Siegbahn for this measurement
method since chemical information is generated.
Using XPS spectra it can be determined which elements are
present in which concentration in the region of the
uppermost atomic layer of materials, and using the
"chemical shift" of the XPS signals, in which chemical
bonding state they are present.

By means of EDP-supported evaluation method, this can be
quantified with good reproducibility. The values determined
herein usually correspond to a figure in area percent.
By reference to overview surface analyses it is possible to
integrally record e.g. 0.5 cm' of a surface, although the
penetration depth of the analysis is limited to the
uppermost atomic layers. In this way, any
microinhomogenities that are present are discovered.
Measurement of the photoelectrons emitted from the sample,
as takes place during the XPS/ESCA technique, records
exclusively the region of the uppermost atomic layers since
the average free path length of these electrons is only a
few atomic layers. Electrons which are released by
ionization processes in deeper layers are no longer able to
reach the surface and thus do not leave the sample.
Consequently, when using soft X-ray excitation radiation
and when measuring the low-energy photoelectrons detached
thereby, the XPS technique is automatically surface-
specific and focused on the surface properties of
materials.
A further advantage of XPS is that - apart from hydrogen
and helium, also light elements such as B, C, N, 0 can be
detected quantitatively and their chemical binding states
can be observed directly.
Figure 3 shows a XPS overview spectrum of Sipernat® 50
laden with 20% by weight of 2-Mi in accordance with the
method according to the invention. It can clearly be seen
which part of the surface is formed by SiO2 and which is
formed by 2-Mi. By means of substrate subtraction and use
of relative sensitivity factors for the elements it is
possible to formulate herefrom, in accordance with
standardized methods, quantitative statements relating to
the surface composition.

Carrying out the XPS measurements
The XPS measurements are carried out on powder beds, where
in each case 0.5 square centimeters are integrally
recorded. In order to avoid contaminations of the samples
and measurement artifacts, the samples are for this purpose
introduced into a gold-coated highest-purity tantalum
sample container (Alfa, 99.98%, ca. 0.25 mm thickness, ca.
1.5 to 2 cm large) in such a way as not to result in any
clumping, caking or compacting of the samples. The amount
of sample is chosen such that the holder is largely filled
or an area of at least 0.5 square centimeters can be
measured. Each sample is then transferred to a prechamber
of the XPS spectrometer (XPS plant Leybold LHS12 or Leybold
MAX 100) and the chamber is evacuated to 10-8 mbar for ca.
2 hours at room temperature. The sample to be investigated
is then transferred to the main chamber of the XPS
spectrometer and the vacuum is increased to 4 x 10-10 mbar
in order to prevent impurities and measurement artifacts
due to possible hydrocarbon contaminations or cross
contaminations. The purity of the vacuum or of the residual
gas in the measurement chamber of the XPS spectrometer is
continuously monitored using a residual gas mass
spectrometer (Quadrex 200, Inficon).
The XPS measurements were carried out according to the ESCA
method using MgKa radiation with an energy of 150 W. The
analyzer of the electron energy (Leybold EA200) is operated
at a transmission energy of 72 e.V. in the "fixed analyzer
transmission mode". The reference used for the bonding
energy scale of the spectrometer was the Au4f7/2 signal of
the SCAA83 standard from the National Physics Laboratory
(NPL, Teddington, GB) at 84 e.V. which is measured before
and after measuring the sample to be investigated. The
electrostatic charge of the samples to be investigated is
compensated by electrons with a low energy from a
controlled incandescent electron source which is attached

in the vicinity of the sample holder. This emission source
in turn is shielded and thermally insulated in order to
prevent direct heat transfer to the sample to be
investigated.
The evaluation was carried out according to the general
recommendations of DIN Technical Report No. 39 and the
report of the National Physics Laboratory DMAA(A)97,
Teddington, GB, January 1987 and the findings to date of
the "Surface and Micro Range Analyses" working committee
NMP816 (DIN). A DS 100 data record was used in order to
evaluate the XPS data by means of standard routines (with
subtraction of the X-ray satellites and the background, and
also taking into consideration the relative sensitivity
factors valid for the spectrometer used (which are stored
in the data system of the spectrometer) of the electron
level reported in each case). All data are in area percent.
The examples below serve to illustrate and explain the
present invention, but do not limit it in any way.
Example 1
a) Introducing the active ingredient into a porous carrier
The carrier material, for example porous SiO2 (e.g.
Sipernat®2200 Degussa) is introduced as initial charge in a
glass vessel. The liquid active ingredient is placed into
the beaker (ratio e.g. 30% by weight of SiO2 to 70% by
weight of liquid active ingredient). The agglomerated
particles are mixed in a Turbula mixer for ca. 30 min until
the particles are pourable again. As a result of the input
of energy and the adsorption and/or capillary forces within
the porous SiO2 structure, the active ingredient is
transported to the center of the carrier. It is likewise
possible to dissolve a nonliquid active ingredient in a
corresponding solvent and then to proceed as described

above. In order to adjust the active ingredient
concentration, the process can be repeated as often as
desired, or solutions with corresponding concentrations can
be prepared. However, a drying step must be carried out
between the steps in order to separate off the solvent.
Precise details are given under experimental description
c).
b) Production of a protection system in the carrier laden
with active ingredient
The supported material is immersed into a solution of wax
and solvent. It is advantageous to select a solvent which
does not dissolve the active ingredient. Preferably, the .
solution is saturated with wax in order to achieve the
highest possible entry into the porous carrier. The
supported particles are gently stirred for ca. 2 min in the
solution before the particles are separated off again via a
filter. After briefly draining off, the particles are dried
in the oven. For this, a temperature below the melting
temperature of the wax and also below the boiling point of
the solvent is chosen. The drying can be carried out under
the aforementioned conditions also in vacuo. After the
particles have been completely dried, the operation is
repeated three times so that at the end four layers of wax
have been applied.
It is likewise possible to apply a thick wax layer over a
wax melt. Here, the active ingredient should be stable in
the melting range of the wax. The supported material can be
heated, for example, to 10 K above the melting temperature
of the wax. At the same time, the capsule material can be
melted. The heated supported material can be introduced as
initial charge in a beaker and supplied with the wax melt,
for example in the ratio 60:40 (% by weight). The material
is then preferably mixed above the melting temperature for
a time which is sufficiently long for the particles to be

pourable again. The particles are then cooled with mixing
at ca. 5°C depending on the encapsulation material.
Finally, a layer of stearic acid can be applied. For this,
the procedure is as described above. The stearic acid is
dissolved in solvent which does not partly dissolve the
layers applied beforehand. The particles are immersed into
the saturated solution for 2 min and then dried.
c) Experimental description
An encapsulation of NaOH was achieved in accordance with
the general production procedure described above with the
following experimental steps:
1. 150 ml of a 10% by weight solution of solid NaOH in
ethanol was applied to 50 g of SiO2 (Sipernat® 2200).
2. The laden particles were dried at 80°C in the drying
cabinet for 12 hours.
3.-6. Points 1 and 2 were repeated two more times in order
to increase the overall loading of the active
substance.
7. The particles obtained according to step 6 were
immersed into a 25 percent strength solution of wax
(Sasol 5403) in n-hexane for two minutes.
8. The drying was then carried out at a temperature of
50°C and 500 mbar vacuum in the drying cabinet.
9.-12. Points 7 and 8 were repeated two more times.
13. Next, the particles were heated to 80°C, mixed with
a stearic acid melt (35 g of stearic acid melt per
100 g of particles) and then solidified in order to
be able to produce a flowable product.

14. Finally, the particles were immersed into a solution
of 10% by weight of stearic acid in ethanol for
2 minutes.
15. The drying was carried out at 50°C and 500 mbar
vacuum in the drying cabinet.
The product was packaged in glass bottles.

Example 2
In order to investigate the stability of the product from
example 1, the product was stirred in a jacketed 1 1 glass
laboratory reactor in water at 23°C or 40°C using a
laboratory propeller stirrer (200 revolutions/min). After
90 minutes, there was no change in the pH. However, if the
temperature is increased above 54°C - the protection system
is designed such that it is opened at 54°C, then the active
ingredient is released. Figure 2 shows the concentration of
the active substance in water as a function of the time and
the water temperature. For the purposes of clarity, the

curve for the release experiment at 40°C has not been
shown. The results of the release experiments clearly
indicate the performance of the formulations according to
the invention. As a result of the extremely good solubility
of sodium hydroxide solution in water, even small openings
or sites of damage in the protection system would mean that
the sodium hydroxide solution is released. This is not the
case for the product systems according to the invention/ as
the storage experiments at 23 and 40°C show. However, if
the temperature is increased to 60°C, then the sodium
hydroxide solution is released. The product systems
according to example 1 thus exhibit good storage stability,
good mechanical stability (was simulated by stirring for
90 minutes) and the active ingredient can be released in a
targeted manner, controllable by external influences.
Example 3
The test sample chosen for example 3 was 2-methylimidazole
(CAS No. 693-98-1) (2-Mi). 2-Mi is a heterocyclic compound
with two nitrogen atoms and two double bonds with a
molecular formula C4H6N2. This substance is used as reaction
initiator for epoxy resin systems (Dyhard®) . The challenge
was to develop an encapsulation formulation in which the
initiator is protected against uncontrolled reaction, where
methylimidazole is known as a very reactive substance. The
release should take place at temperatures above 80°C, at
which the epoxy resin curing is started. Below this
temperature, no reaction must take place and the reactive'
substance must not escape from the encapsulated particles.
It is known that 2-Mi is very readily soluble in a
multitude of organic solvents, including water.
The solids carrier used was Sipernat® 50 from Evonik
Degussa GmbH. The encapsulation can be carried out in
principle by 2 different variants:

In variant a), the carrier material is introduced as
initial charge in a mixer and heated to the melting
temperature of the active ingredient. The active ingredient
is then added. The 2-Mi is melted in the mixing unit and .
introduced homogeneously into the carrier material by the
mixing operation. In variant b), the 2-Mi is applied from
the solution. For this, the carrier material is likewise
introduced in the kneader as initial charge, but the
kneader is not heated. The 2-Mi is dissolved in a
corresponding solvent - as regards the selection of the
corresponding solvent, see explanations in the
description - and then fed to the mixing unit with the
carrier material.
In both process variants, the active ingredient is applied
to the carrier material by atomization.
It has been observed that application from the melt
achieves a higher loading of the particles.
Following the general - above-described - principles, an
encapsulation of 2-Mi according to variant a) was carried
out as follows:
1. 50 g of Sipernat® 50 are introduced as initial charge
in a kneader and heated to 170°C with mixing in the
apparatus and constantly further stirred.
2. In a beaker, 80 g of 2-Mi are melted with stirring at
150°C using a hotplate.
3. With constant stirring, the molten 2-Mi of the initial
charge is slowly metered into the kneader by adding
dropwise. Here, 60 g of 2-Mi are metered in over 30 min
(dropwise addition).
4. The mixture is kneaded at 170°C for 60 min. This gives
a pourable intermediate.

5. The temperature in the kneader is then reduced to
100°C.
6. In a beaker, 140 g of wax C80 is melted at 90°C.
7. The wax is added dropwise to the mixture over 60 min.'
8. The mixture is kneaded at 100°C for 60 min. This gives
a pourable intermediate.
9. The temperature in the kneader is then reduced to 80°C.
10. In a beaker, 70 g of stearic acid are melted at 70°C.
11. The stearic acid is added dropwise to the mixture over
30 min. This gives a viscous mass.
12. In a drying cabinet, 50 g of Sipernat® 50 are heated to
80°C.
13. The Sipernat® from 12. is metered into the mixture from
step 11 (spoonwise addition).
14. The mixture is kneaded at 80°C for 60 min. This gives a
pourable product.
15. The kneader is cooled to room temperature and the
finished product is removed and packaged in a glass
bottle.
Substances used:
1. 2-Methylimidazole Merck CAS No.: 693-98-1
2. Wax Sasol Name C80
3. Stearic acid Merck CAS No.: 57-11-4
4. Carrier material Sipernat® 50 Evonik
Instruments used:

1. Kneader Manufacturer IKA
Name measurement kneader H60
2. Magnet stirrer/hotplate Manufacturer IKA
Name RCT basic
Selection of the protective material depends primarily on
the release conditions. In the above case of the
encapsulated 2-Mi, the protective material should have a
melting point of more than 80°C since the release is to
take place within this temperature range.
Example 4
Production of product systems analogous to example 3) but
with preimpregnation of the carrier material
As a variation on example 3, in order to influence the
surface properties of the Sipernat® 50, prior to
application of the active ingredient, a treatment of the
Sipernat6 50 with the surfactant Tego Twin 4000 was carried
out. For this, the carrier material was introduced as
initial charge in a mixer and the surfactant Tego Twin 4000
was applied preferably in a weight ratio of carrier
material to surfactant of 5:1. The protection system is
then generated as described in steps 1 to 15 of example 3.
Example 5
Production of a product system corresponding to example 3)
but with prior evacuation of the carrier material
As a variation of example 3, Sipernat® 50 from Evonik
Degussa GmbH was introduced as initial charge in a mixer
and heated to the melting temperature of the active
ingredient. The 2 Mi is then added to the mixer. The mixing
unit was evacuated to 200 mbar abs, the 2-Mi is melted in

the mixing unit and homogeneously introduced into the
carrier material by the mixing operation. The further steps
were carried out as described in example 3.
Example 6
The structure of the product systems from example 3) was
investigated
To characterize the particle structure, XPS surface
analyses were carried out on an encapsulated sample (as in
example 3) and on an unencapsulated sample of the active
ingredient 2-methylimidazole. The measurement was carried
out on a powder bed of the sample over an area of 0.5 cm2.
Photoelectron spectroscopy XPS gives information about the
elemental coating of the particle surface. Table 2 shows
the results of the analysis. The figures are in atomic
percent. Assuming that the amount of adsorbed carbon is
constant at 7% (carbon loading of 7% was ascertained
beforehand when measuring the pure carrier material
Sipernat® 50 (see table 2 below)), the molecular fractions
is inferred from the stated values.
Figure 3 shows a XPS overview spectrum of Sipernat® 50
laden with 20% by weight, i.e. the product according to
stage 4 of the method from example 3. It can clearly be
seen, in particular from the N, 0 and Si peaks, that the
2-Mi has been absorbed almost completely into the pores of
the carrier material and only very small amounts have
remained on the surface.
The evaluation of the XPS spectra of the end product
according to example 3 is given in table 2 below.
Table 2: results of the XPS measurement


The results from table 2 above show that 16% of the
particle surface in the product system according to
example 3 is formed by SiO2. This confirms that the
protection system is largely located in the pores of the
carrier material and the pore walls made of hard SiO2
extend up to the surface of the product system, where they
bring about mechanical abrasion protection. A complete
protective shell around the carrier material - as in the
case of a "core/shell" system - is clearly not present. In
addition, the results indicate that although no
inactivation of the active ingredient or separate washing
steps were carried out with the product systems according
to the invention as in example 3, only 7.3% of 2-Mi are
present on the particle surface and thus the majority of
the 2-Mi was soaked into the pores of the carrier.
Example 7:
In this example, the storage stability of resins comprising
a hardener and 2-Mi as accelerator was investigated. For
this, in one case a 2-Mi encapsulated according to the
invention (with 20% by weight active ingredient loading)

and in another case pure 2-Mi was incorporated into a
mixture of a resin and a hardener and the mixture was
investigated rheologically in order to measure the
hardening of the system. Here, as the viscosity increases,
the hardening is more advanced.





As can be seen from table 3 above, the resin comprising
pure 2-Mi has already completely hardened after 5 days and
is no longer processable. However, when using the product
systems according to the invention, even after 8 days, the
viscosity is still better than when using pure 2-Mi. Even
after a storage time of 3 weeks, the resin comprising the
product systems according to the invention is still liquid
and can still be processed. Consequently, the processing
time was more than quadrupled. A further advantage is that,
after 3 weeks and after processing the resin, the
protection system can be destroyed through targeted
activation and therefore the 2-Mi can be rapidly released.

We Claim:
1. A product system comprising
- at least one inorganic and/or organic porous
carrier,
- at least one active ingredient which is introduced
into the porous carrier, and
- at least one further substance of the at least part
of the total amount present in the product system is
introduced in the pores of the carrier material,
characterized in that, detected by investigating the
outermost atomic layer of the product system by mean's
of XPS, at least part of the outermost surface of the
product system is formed by the carrier material.

2. The product system as claimed in claim 1,
characterized in that at least 10% of the surface of
the product system, detected by investigating the
outermost atomic layer of the product system by means
of XPS, is not formed by active ingredient/active
ingredients and/or protective substance/protective
substances.
3. The product system as claimed in one of the preceding
claims, characterized in that the protection system
comprises at least one compound which is soluble in a
solvent in which the active ingredient is not soluble.
4. The product system as claimed in one of the preceding
claims, characterized in that the active ingredient is
soluble in a polar solvent and the protective layer is
insoluble in water and/or soluble in a nonpolar
solvent, or that the active ingredient is soluble in a
nonpolar solvent and the protection system is insoluble
in this nonpolar solvent and/or is soluble in a polar
solvent and/or water.

5. The product system as claimed in claim 4, characterized
in that the nonpolar solvent is an aromatic
hydrocarbon, an alkane or a cycloalkane.
6. The product system as claimed in one of the preceding
claims, characterized in that the weight ratio of
protection system to active ingredient is in the range
from 10:1 to 1:10.
7. The product system as claimed in one of the preceding
claims, characterized in that the loading of the porous
carrier with active ingredient is 1% by weight to 9% by
weight or at least 10% by weight to 90% by weight,
based on the DBP absorption of the porous carrier.
8. The product system as claimed in one of the preceding
claims, characterized in that the loading of the porous
carrier with protection system is at least 10% by
weight, based on the DBP absorption of the porous
carrier.
9. The product system as claimed in claim 7 or 8,
characterized in that the unladen inorganic and/or
organic porous carrier has a DBP absorption of at least
180 g/100 g.
10. The product system as claimed in one of the preceding
claims, characterized in that the product system is
particulate.
11. The product system as claimed in claim 10,
characterized in that the particles have an average
particle size d50 in the range from 5 pm to 1000 pm.
12. The product system comprising

- at least one inorganic and/or organic porous carrier,
- at least one active ingredient which is introduced
into the porous carrier, and
- at least one further substance of the at least part

of the total amount present in the product system is
incorporated in the pores of the carrier material,
characterized in that these further
substance/substances forms/form a protection system for
the active ingredient/active ingredients which is
designed such that, through a deactivation of the
protection system as a result of an input of energy
and/or chemical conversion and/or breakup of the
protection system, the protection system is changed in
such a way that, preferably spontaneously, at least 50%
by weight of the active ingredient/active ingredients
is/are released.
13. The product system as claimed in claim 12,
characterized in that the protection system is
designed such that an input of energy through pressure
waves, preferably ultrasound treatment and/or
irradiation with UV light, and/or by increasing the
temperature, triggers the release of the active
ingredient/the active ingredients.
14. The product system as claimed in claim 13,
characterized in that, following the action of
pressure waves on the product system, at least 80% by
weight of the active ingredient/the active ingredients
is/are released within 1 h.

15. The product system as claimed in claim 13,
characterized in that, following the action of UV
radiation on the product system, at least 80% by weight
of the active ingredient/active ingredients is/are
released within 12 h.
16. The product system as claimed in claim 13,
characterized in that, after increasing the temperature
of the product system, at least 601 by weight of the
active ingredient/active ingredients is/are released
within 60 min.

17. The product system as claimed in claim 12,
characterized in that, as a result of chemical
conversion and/or as a result of a pH shift and/or
action of at least one enzyme, the release of the
active ingredient/active ingredients is triggered.
18. The product system as claimed in claim 17,
characterized in that, as a result of a pH change, at
least 70% of the active ingredient/active ingredients
is/are released within 8 h.
19. The product system as claimed in claim 18,
characterized in that, as a result of the action of at
least one enzyme on the protection system, at least 80%
by weight of the active ingredient/active ingredients
is/are released within 24 h.
20. The product system as claimed in claim 12,
characterized in that, as a result of dissolving the
protection system in a suitable solvent over the course
of 24 hours, at least 80% by weight of the active
ingredient/active ingredients is/are released.
21. The product system as claimed in one of claims 12 to
20, characterized in that, after destroying the
protection system by diffusion, at least 80% by weight
of the active ingredient/active ingredients is/are
released within 20 days.
22. A method for producing a product system as claimed in
one of the preceding claims, characterized in that an
active ingredient is introduced into a porous carrier
and a protection system is produced.
23. The method as claimed in claim 22, characterized in
that it comprises the following steps:
a) introduction as initial charge of at least one
carrier material in a solids mixing unit

b) optional evacuation of the solids mixing unit
c) optional preimpregnation of the carrier material
with at least one protective substance until at
most 50% by weight of the DBF absorption value is
achieved
d) addition of at least one active ingredient to the
solids mixing unit
e) impregnation of the carrier with active ingredient
f) optional inhibition of the active ingredient
adhering to the outer particle surface of the
carrier material and/or washing and/or drying
g) addition of at least one protective substance
h) impregnation of the carrier with at least one
protective substance
i) optional washing and/or drying
j) optional reactive inhibition of the active
ingredient adhering to the external particle
surface of the carrier material and/or washing
and/or drying.
24. The method as claimed in claim 23, characterized in
that stages b) to e) and/or g) to h) are carried out
several times, where, in the case of the repetition of
steps d) and e) and/or g) and h), in each case
identical or different active ingredients and/or
protective substances can be used.
25. The method as claimed in one of claims 22 to 24,
characterized in that the carrier material and the
active ingredient/active ingredients are mixed before
they are introduced into the solids mixing unit.

26. The method as claimed in one of claims 22 to 25,
characterized in that a pretreatment of the carrier
material with surfactants or silanes takes place before
the active ingredient and/or protection system is
added.
27. The method as claimed in claim 26, characterized in
that, in stage c), a mixture of at least one active
ingredient and at least one protective substance is
added.
28. The method as claimed in one of claims 22 to 27,
characterized in that the added amount of protective
substance/protective substances in step g) is regulated
such that the total amount of active ingredient/active
ingredients and protective substance/protective
substances which is added during the production of the
product systems corresponds to 50% by weight to 100% by
weight of the DBP absorption value of the carrier
material.
29. The method as claimed in one of claims 22 to 28,
characterized in that the added amount of protective
substance/protective substances in step g) is regulated
such that the total amount of active ingredient/active
ingredients and protective substance/protective
substances which is added during the production of the
product systems is greater than the total pore volume
of the carrier material and that the excess of
protective substance/protective substances is absorbed
by adding carrier material and/or carrier material
laden with active ingredient/active ingredients.
30. The method as claimed in one of claims 22 to 29,
characterized in that the mixing intensity and the
metering are matched to one another such that the
pourability at the end of the application process is
ensured.

31. The method as claimed in one of claims 22 to 30,
characterized in that the stirring elements are
selected such that no abrasion takes place as a result
of shear stress.
32. The use of a product system as claimed in one of
claims 1 to 21 for producing foods, feeds, medicaments,
products for the land and forestry, cosmetics,
components for coating formulations and adhesive
formulations or components for sports equipment and
sports clothing.


The present invention relates to storage-stable product
systems having high latency and good mechanical
stability, which are suitable, inter alia, for premix
formulations. Furthermore, the present invention
relates to a method for producing the formulations
according to the invention and the use thereof.

Documents:

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Patent Number 278372
Indian Patent Application Number 3364/KOLNP/2010
PG Journal Number 53/2016
Publication Date 23-Dec-2016
Grant Date 21-Dec-2016
Date of Filing 13-Sep-2010
Name of Patentee EVONIK DEGUSSA GMBH
Applicant Address RELLINGHAUSER STRASSE 1-11, 45128 ESSEN GERMANY
Inventors:
# Inventor's Name Inventor's Address
1 TSCHERNJAEW, JURI UMENHOFSTR. 9A 63743 ASCHAFFENBURG GERMANY
2 STENNER, PATRIK MARTIN-LUTHER-KING-STR.22B 63452 HANAU GERMANY
3 PISULA, WOJCIECH KAISER-WILHELM-RING 44 55118 MAINZ GERMANY
4 DREXEL, CLAUS-PETER EICHENDORFFSTR. 16 63263 NEU-ISENBURG GERMANY
5 GOTTHEIS, MARTINA LEIPZIGER STRASSE 52 63505 LANGENSELBOLD GERMANY
6 SEITZ, TANJA UNTERGASSE 10 B 63505 LANGENSELBOLD GERMANY
7 HITZLER, MARTIN, G. JOSEF-BREU-STR. 21 83342 TACHERTING GERMANY
PCT International Classification Number B01J 2/00
PCT International Application Number PCT/EP2009/051137
PCT International Filing date 2009-02-02
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 102008000290.9 2008-02-13 Germany