Title of Invention

MOULDING MATERIAL FOR THE PRODUCTION OF HIGHLY FLAME RESISTANT ARTICLES, A PIGMENT THEREFOR AND USE THEREOF

Abstract ABSTRACT Title: Moulding material for the production of highly flame resistant articles, a pigment therefore and use thereof. A moulding material for the production of highly flame resistant articles with a matrix formed from a thermoplastic and with a particulate flame retardant pigment dispersed therein, characterized in that under the influence of laser light the pigment changes colour or the colour of the plastic matrix changes, and in that the pigment is a reaction product of at least one halogen-free flame retardant organic nitrogen base with a salt or a salt mixture which can be reacted with the organic nitrogen base.
Full Text

MOULDING MATERIAL FOR THE PRODUCTION OF HIGHLY FLAME
RESISTANT ARTICLES, A PIGMENT THEREFOR AND USE THEREOF
Adding flame retardant material in the form of fine particles to plasties and dispersing
those fine particles through the whole plastic article or in its surface regions is known. As an
example, German patent specification DE-A-101 45 093 describes polyphosphates of organic
nitrogen bases, such as guanidine and melamine or melamine derivatives, as a flame protection
agent (retardant) in plastics and as a flame proofing agent in textiles. International patent
WO-A-00/02869 describes polyphosphate salts, in particular in glass fibre-reinforced
polyamides and polyesters, as flame protection agents. Other organic nitrogen bases are
proposed in many other publications as flame protection agents, the tendency in this branch of
the industry being to use halogen-free flame protection agents such as aluminium hydroxide,
magnesium hydroxide or melamine cyanurate for that purpose.
When such flame protection agents are distributed in halogen-free thermoplastic plastics,
a disadvantageous effect may occur which changes the properties of the plastic in an undesirable
manner.
In many fields of application, it is desirable to make plastic articles which are flame-
proof and capable of being written or marked using laser light; there is a practical problem,
however, as halogen-free flame-proof flame protection agents do not exhibit sufficient contrast,
and so they turn out to be of no practical use.
The aim of the invention is to provide plastic moulding materials which can ensure that
plastic articles can be made laser-writable without essentially deleteriously affecting the
properties of the plastic. The moulding material of the invention for the production of highly
flame resistant articles with a matrix formed from a thermoplastic and with a particulate flame
retardant pigment dispersed therein is characterized in that under the influence of laser light the
pigment changes colour or the colour of the plastic matrix changes, and in that the pigment is a

reaction product of at least one halogen-free flame retardant organic nitrogen base with a salt or
a salt mixture which can be reacted with the organic nitrogen base.
Any known thermoplastic may be used as the matrix material, optionally glass fibre-
reinforced, which is described, for example, in Ullmann's Encyclopedia of Chemistry (volume
15, page 457) and which has already been used for laser marking. Examples of suitable plastics
are polyethylene, polypropylene, polyamide, polyester, polyphenylene oxide, polyacetal.
polybutylene terephthalate, polytnethacrylate, polyoxymethylene, polyvinylacetal, polystyrene,
acrylic-butadiene-styrene (ABS), acrylonitrile-styrene-acrylic ester (ASA), polycarbonate,
polyether sulphone, polyethylether ketone, polyvinylchloride and thermoplastic polyurethane.
Preferred polyesters are thermoplastic polymers with repeating ester groups in the main
chain. Examples are polycondensation products of naphthalene dicarboxylic acid, terephthalic
acid, isophthalic acid, adipic acid, azelaic acid, sebacinic acid, dodecane dioic acid and
cyclohexane dicarboxylic acids with diols such as ethylene glycol, 1,3-propanediol, 1,4-
butanediol, 1,4-butenediol or 1,6-hexanediol, 1,4-hexanediol, 1,4-cyclohexanediol, 1,4-di-
(hydroxymethyl)-cyclohexane, bisphenol A, neopentylglycol, oligo- or poly-ethylene glycols,
oligo- or poly-propylene glycols, oligo- or poly-(tetramethylene) glycols, mixtures of said diols
and ester-forming derivatives thereof. Particularly preferred matrix components are
polyethylene terephthalate, polybutylene terephthalate and polyether-ester block copolymers.
The polyamides which may be considered are thermoplastic polymers with repeating acid
amide groups in the main chain, both homopolymers and copolymers with further co-monomer
groups.
Examples are polyhexamethyleneadipinic acid amide, polyhexamethylene azelaic acid
amide, polyhexamethylene sebacinic acid amide, polyhexamethylene dodecane dioic acid amide,
poly-1 1-aminoundecane acid amide and bis-(p-amino-cyclohexyl)-methanedodecane acid amide
or products obtained by ring opening of lactams, for example polycaprolactam or
polylaurinlactam. Further, polyamides based on terephthalic or isophthalic acid as the acid

components and/or trimethylhexamethylene diamine or bis-(p-aminocyclohexyl)-propane as the
diamine component, as well as polyamide resins produced by copolymerizing two or more of the
above polymers or their components, are suitable.
The thermoplastic polymers used as mixing partners can be any other partially
crystalline, liquid crystalline or amorphous polymers.
Polyurethane is particularly suitable because its mechanical properties are good and it can
be processed cheaply. Thermoplastic polyurethanes are well known from many publications in
the literature and from patents.
Highly surprisingly, the components of the salt produce an improvement in contrast as
regards laser-writability or -markability and simultaneously produce an improvement in flame
protection.
The inventive effects described above are obtained by dint of the pigment which on the
one hand has flame retardant properties and on the other hand produces laser-writability by
absorption of laser light. This pigment is a reaction product of at least one halogen-free flame
retardant organic nitrogen base with a reactive salt or salt mixture which can react with the
nitrogen base. The organic nitrogen base is advantageously melamine or a melamine derivative
such as melamine cyanurate, melamine orthophosphate, di-melamine orthophosphate, melamine
pyrophosphate, melamine polyphosphate, melamine borate, a melamine salt of a phosphorus acid
partial ester, one or more salts of phosphoroxy compounds, ammonium polyphosphate, boron
phosphate and combinations thereof. The flame protection agents used can also be used in
triazine polymers, melem, melam, urea, guanidine etc.
The term "salt" as used herein means compounds which at least partially dissociate in
water into cations and anions or consist of an acid residue and a base residue.
The term "colour change" can mean a transfer from one tone to another, such as from
yellow to red, or from transparent to black. In the context of the invention, this term also means

a change in lightness, for example from light brown to dark brown or to a colour change in the
plastic matrix.
The term "particulate" means that the pigment is in the form of fine solid particles with
quantitative parameters being given as the mean particle size (d50) and the particle size of the
primary particles. The size of the primary particles is in the nanometer to micrometer range.
Suitable primary particles have a mean particle size (d50) of less than 10 µm, preferably less than
5 µm.
Within the scope of the invention, the pigments in accordance with the invention can also
contain further cations, in particular those from elements from periods 2 to 5 in group 1. It is also
possible to add to the pigments additional inorganic oxides and/or further colour-producing
additives and/or additives which modify the usual properties, such as UV stabilizers, stabilizers
against efflorescence, thermal and thermo-oxidative attacks, to improve hydrolytic and azidolytic
resistance, lubricants, unmoulding aids, nucleation agents, fillers, softeners and other additives.
Normally, the elements are selected so that they have as strong an absorption as possible
in the wavelength range of the laser light which is used.
The wavelength ranges of the laser light employed do not constitute a limitation.
Suitable lasers generally have a wavelength in the range 157 nm to 10.6 mm. Examples are CO2
lasers (10.6 mm) and Nd:YAG lasers (1064 nm) or pulsed UV lasers.
Typical excimer lasers have the following wavelengths: F2 excimer laser (157 nm), ArF
excimer laser (193 nm), XeCl excimer laser (308 nm), XeF excimer laser (351 nm), frequency
multiplied Nd:YAG laser with wavelengths of 532 nm (frequency doubled), 355 nm (frequency
trebled) or 265 nm (frequency quadrupled). Particularly preferably, Nd:YAG lasers (1064 or
532 nm) and CO2 lasers are used. The energy densities of the lasers employed in the present
invention are generally in the range from 0.3 mJ/cm2 to 50 J/cm2, preferably 0.3 mJ/cm2 to 10

J/cm2. When using pulsed lasers, the pulse frequency is generally in the range 1 to 30 kHz.

In the context of this description, the term "pigments" means organic or inorganic salt
type compounds or mixtures of salt type compounds which change colour under the influence of
a laser light source at the illuminated areas.
These compounds can be conventional salts with a definite stoichiometry of one or more
anions with cations derived from different elements, but they can also be non-stoichiometric
compounds. Anions of organic carboxylic acids as well as carbonic acids are preferred.
Any anion can be used, but anions of organic carboxylic acids as well as oxoanions with
the exception of phosphinales, diphosphinates and/or their polymers and/or carbonic acid anions
are preferred.
Preferred combinations are those in which the non-illuminated compound absorbs in the
region of the light wavelength employed.
More preferred combinations are those in which the self colour of the non-illuminated
compound can be adjusted by varying the mole ratios of the cations.
In a preferred embodiment of the invention, the non-illuminated compound has the
highest possible lightness and as little as possible self colour. In this case, the illuminated
compound should have as low a lightness as possible and nevertheless as little self colour as
possible.
In a further preferred embodiment of the invention, the non-illuminated should have as
high a lightness as possible and as little self colour as possible; on the. other hand, the
illuminated components should have the clearest possible self colour.
In a preferred embodiment of the composition of the invention, the anions of the above
components have general formula AaO0(0H)yz-, where A = tri- or penta-valent phosphorus, tetra-
valent molybdenum or hexa-valent tungsten;
a, o and z independently represent whole numbers with values from, 1-20; and
y is a whole number with values from 0-10.

In a further preferred embodiment of the composition of the invention, the pigment has at
least one combination of two different elements of the group consisting of copper, tin, antimony
and iron.
In a particularly preferred embodiment of the composition of the invention, the pigment
contains anions of phosphorus (V) and/or phosphorus (III) acid, their condensation products or if
appropriate with further hydroxide ions, and Cu and Fe or Cu and Sn or Cu and Sb or Sn and Fe
as the cations.
Preferably, metallic salts are used which have a particularly high thermal stability so that
no degradation occurs when doped into the polymer to produce the combination product. Salts
or ligands with a thermal stability of over 200°C (2% weight loss), preferably with a stability of
over 250°C (2% weight loss) and more particularly with a stability of over 3()0°C (2% weight
loss) are used.
Light sensitive flame protection agent combinations are obtained by doping, reacting and
mixing the organic nitrogen bases with the metallic compounds. The, term "doping" means both
the production of mixtures of one or more of said solid ingredients in the powdered state as well
as mixing one or more of said solid ingredients in a dissolved or suspended state with subsequent
drying of the powdered product.
The products of the invention have flame retardant and laser-writable properties.
The invention also concerns pigments for the manufacture of simultaneously flame
retardant and laser-writable plastic articles with the features defined above for the moulding
material. The invention also concerns the use of pigments with the features given above for the
manufacture of similarly flame retardant and laser-writable plastic articles, in particular from
thermoplastic.
Example 1
Pigment for a moulding material of the invention was produced as follows:

Copper hydroxide (0.1 mole) and isocyanuric acid (0.1 mole) were placed in a mixer with
water and mixed by agitation. Thus, a neutralization reaction took place to form a salt. After 30
min, melamine (10 mole) and cyanuric acid (10 mole) were added in an exact ratio of 1:1. The
whole mixture was stirred for 1 h and then vacuum dried at 110°C.
A moulding material of the invention was obtained with the pigment obtained by using
the following ingredients. Its flame resistance and laser-writability were determined.
The laser was a commercially available Nd-YAG laser (wavelength 1064 nm). The
contrast values were determined using a digital camera mounted on a microscope and image
evaluation software. The flame resistance was determined using a UL Box in accordance with
UL94. The CT1 values were determined in accordance with standard DIN I EC 601 12/VDE 0303
Part I, RAL 7035.
Polyamide 6,6/6 (mole ratio 1:1) 88 wl %
Melamine cyanurate (produced as above) 12 wt %
UL94 VO
Contrast (K value) 4,2
CTI 520
The thermoplastic moulding materials obtained were distinguished by both their superb
llame resistance (self-extinguishing) and by their high contrast values (K value) on laser-writing.
Example 2
Pigment for a moulding material of the invention was produced as follows:
A 50 I reactor with a stirrer was filled with 29.25 I of pure water. Orthophosphoric acid
(74.75 mole) was added at ambient temperature, with stirring. Because the reaction was
exothermic, the temperature of the reactor contents rose and was maintained at 50°C for 10
minutes. Next, melamine (74.75 mole) was added slowly with stirring, avoiding clumping.
After a homogeneous suspension had been obtained, copper hydroxide (7.47 mole) was added to

the suspension. The whole mixture was stirred for 1 h at 100°C then the temperature was raised
and it was vacuum dried.
The doped melamine orthophosphate obtained was transformed into melamine
polyphosphate in a furnace at 340°C. The product was then ground to a fineness of 5 microns.
Polyamide 50wt%
Glass fibres 30 vvt %
Melamine cyanurate 10 vvt %
Melamine polyphosphate (produced as above) 10 wt %
UL94 VO
Contrast (K value) 2.8
CT1 590 V
This moulding material also had superb flame resistance and laser-writability (K value).

WE CLAIM:
1. A moulding material for the production of highly flame resistant articles with a
matrix formed from a thermoplastic and with a particulate flame retardant
pigment dispersed therein, characterized in that under the influence of laser light
the pigment changes colour or the colour of the plastic matrix changes, and in that
the pigment is a reaction product of at least one halogen-free flame retardant
organic nitrogen base with a salt or a salt mixture which can be reacted with the
organic nitrogen base.
2. A moulding material as claimed in claim 1, wherein its pigment has a mean
particle size (d50) of less than 10 µm, preferably less than 5um.
3. A moulding material as claimed in claim 1 or claim 2, wherein its pigment
contains salt type compounds with oxoanions with the exception of phosphinates
and diphosphinates and/or polymers thereof, anions of organic carboxylic acids or
anions of carbonic acid.
4. A moulding material as claimed in claim 3, wherein its pigment contains, as the
anions, phosphorus containing oxoanions, in particular phosphate-, condensed
phosphate-, phosphonate-, phosphite- and mixed hydroxide-phosphate-oxoanions
and/or cyanurate anions.

5. A moulding material as claimed in one of claims 1 or 4, wherein the anions of the
pigment have general formula Aa O0 (OH)y2-, wherein A represents tri-orpenta-
valent phosphorus, tetra-valent molybdenum or hexa-valent tungsten, a, o and z
independently represent whole numbers in the range 1 to 20 and y represents a
whole number between 0 and 10.
6. A moulding material as claimed in one of claims 1 to 5, wherein the cations of its
pigment consists of copper, tin, antimony, iron and/or boron.
7. A moulding material as claimed in one of claims 1 to 6, wherein the anions of the
salts consist of phosphorus (V) acid and-or phosphorus (III) acid or condensation
products thereof, if appropriate with further hydroxyl ions, and the cations consist
of Cu and Fe or Cu and Sn or Cu and Sb or Sn and Fe.
8. A pigment as claimed in one of claims 1 to 7, wherein the salts are selected so that
the non-illuminated pigment absorbs in the region of the wavelength of the light
to be used.

9. A moulding material as claimed in one of claims 1 to 8, wherein its thermoplastic
matrix consists of optionally glass fibre-reinforced polypropylene, polyethylene,
polyamide, polybutylene terephthalate, polyethylene terephthalate, polyester,
polyphenylene oxide, polyacetal, polymethacrylate, polyoxymethylene,
polyvinylacetal, polystyrene, acrylic-butadiene-styrene (ABS), acrylonitrile-
styrene-acrylic ester (ASA), polycarbonate, polyethersulphone, polyether ketone,
polyvinylchloride, thermoplastic polyurethane and/or corpolymers thereof and/or
mixtures thereof.
10. A moulding material as claimed in one of claims 1 to 9, wherein the halogen-free
organic nitrogen base consists of melamine, melamine cyanurate, melamine
orthophosphate, dimelamine orthophosphate, melamine pyrophosphate,
melamine-polyphosphate, melamine borate, a melamine salt of a phosphorus acid
partial ester, further salts of III- and V-valent phosphoroxy compounds,
ammonium polyphosphate, boron phosphate and/or mixtures thereof as well as
mixtures thereof with synergistic agents such as pentaerythritol, dipentaerythritol,
THEIC, triacin polymers, urea, guanidine, melem or melam, or phosphonic acid
salts.

ABSTRACT
Title: Moulding material for the production of highly flame resistant articles, a pigment
therefore and use thereof.
A moulding material for the production of highly flame resistant articles with a matrix
formed from a thermoplastic and with a particulate flame retardant pigment dispersed
therein, characterized in that under the influence of laser light the pigment changes colour
or the colour of the plastic matrix changes, and in that the pigment is a reaction product
of at least one halogen-free flame retardant organic nitrogen base with a salt or a salt
mixture which can be reacted with the organic nitrogen base.

Documents:

01240-kolnp-2007-abstract.pdf

01240-kolnp-2007-claims.pdf

01240-kolnp-2007-correspondence others 1.1.pdf

01240-kolnp-2007-correspondence others 1.2.pdf

01240-kolnp-2007-correspondence others 1.3.pdf

01240-kolnp-2007-correspondence others.pdf

01240-kolnp-2007-description complete.pdf

01240-kolnp-2007-form 1.pdf

01240-kolnp-2007-form 2.pdf

01240-kolnp-2007-form 3.pdf

01240-kolnp-2007-form 5.pdf

01240-kolnp-2007-gpa.pdf

01240-kolnp-2007-international publication.pdf

01240-kolnp-2007-international search report 1.1.pdf

01240-kolnp-2007-international search report.pdf

01240-kolnp-2007-pct others.pdf

01240-kolnp-2007-pct request.pdf

01240-kolnp-2007-priority document 1.1.pdf

01240-kolnp-2007-priority document.pdf

1240-KOLNP-2007-(15-12-2011)-AMANDED CLAIMS.pdf

1240-KOLNP-2007-(15-12-2011)-CORRESPONDENCE.pdf

1240-KOLNP-2007-(15-12-2011)-DESCRIPTION (COMPLETE).pdf

1240-KOLNP-2007-(15-12-2011)-EXAMINATION REPORT REPLY RECEIVED.pdf

1240-KOLNP-2007-(15-12-2011)-FORM-1.pdf

1240-KOLNP-2007-(15-12-2011)-FORM-2.pdf

1240-KOLNP-2007-(15-12-2011)-FORM-3.pdf

1240-KOLNP-2007-(15-12-2011)-FORM-5.pdf

1240-KOLNP-2007-(15-12-2011)-OTHER PATENT DOCUMENT.pdf

1240-KOLNP-2007-(15-12-2011)-OTHERS.pdf

1240-KOLNP-2007-(15-12-2011)-POWER OF ATTORNEY.PDF

1240-KOLNP-2007-(23-04-2012)-CORRESPONDENCE.pdf

1240-KOLNP-2007-CORRESPONDENCE.pdf

1240-KOLNP-2007-EXAMINATION REPORT.pdf

1240-KOLNP-2007-FORM 18.pdf

1240-KOLNP-2007-FORM 26.pdf

1240-KOLNP-2007-FORM 3.pdf

1240-KOLNP-2007-FORM 5.pdf

1240-KOLNP-2007-GRANTED-ABSTRACT.pdf

1240-KOLNP-2007-GRANTED-CLAIMS.pdf

1240-KOLNP-2007-GRANTED-DESCRIPTION (COMPLETE).pdf

1240-KOLNP-2007-GRANTED-FORM 1.pdf

1240-KOLNP-2007-GRANTED-FORM 2.pdf

1240-KOLNP-2007-GRANTED-SPECIFICATION.pdf

1240-KOLNP-2007-OTHERS.pdf

1240-KOLNP-2007-REPLY TO EXAMINATION REPORT.pdf


Patent Number 252931
Indian Patent Application Number 1240/KOLNP/2007
PG Journal Number 24/2012
Publication Date 15-Jun-2012
Grant Date 11-Jun-2012
Date of Filing 10-Apr-2007
Name of Patentee CHEMISCHE FABRIK BUDENHEIM KG.
Applicant Address RHEINSTRASSE 27 55257 BUDENHEIM, GERMANY
Inventors:
# Inventor's Name Inventor's Address
1 MANS FIBLA, VINCENS CALLE VILA VALL LLEBRERA, 12 08915 BADALONA, SPAIN
2 WISSEMBORSKI, RUDIGER HEIDESHEIMER STR. 41 55218 INGELHEIM, GERMANY
3 FUTTERER, THOMAS ELTVILLER STR. 17 65197 WIESBADEN, GERMANY
4 NAGERL, HANS-DIETER SCHILLERSTR. 77 67373 DUDENHOFEN, GERMANY
PCT International Classification Number B41M 5/26
PCT International Application Number PCT/EP2005/055285
PCT International Filing date 2005-10-14
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10 2004 050 478 4 2004-10-15 Germany