Title of Invention

"A COMPOSITION FOR INHIBITING THE GROWTH OF MICROORGANISM ON NON-CELLULOSIC FIBRES"

Abstract A composition for inhibiting the growth of microorganisms on non-cellulosic fibres having a moisture regain of  5%, comprising; i) 1 to 50 wt% of at least a self-crosslinkable resin; ii) 0.25 to 20 wt% of at least a catalyst; iii) 0.1 to 4 wt% of at least an antimicrobial active agent, reactive with the resin; iv) 98.65 to 26 wt% of water; wherein i) + ii) + iii) + iv) = 100%.
Full Text The present invention relates to a composition.
The present invention relates to a composition for inhibiting the growth of microorganisms on non-cellulosic fibres comprising a self-crosslinkable resin, a catalyst and an antimicrobial active agent that is reactive with the self-cross-linkable resin; a method for treating non-cellulosic fibres with the composition and non-cellulosic fibres treated with the composition.
The use of antimicrobial active agents for treating cellulosic fibres is well known. During the processing of cellulosic fibres such as cotton and viscose, oxidation of cellulose takes place with the formation of carboxylic acid groups. Cationic antimicrobial active agents such as poly(hexamethylene biguanide) can be attached to cellulosic fibres by means of ionic bonding between the cationic antimicrobial active agents and anionic carboxylic acid groups.
JP 5-226185 discloses a process for fixing a polyhexamethylene biguanide type compound to a textile material by crosslinking the antimicrobial active agent to textiles having hydroxy functionality with a crosslinking agent.
There is however a need for treating non-cellulosic fibres with antimicrobial active agents. Non-cellulosic fibres include but are not limited to protein based fibres of animal origin such as wool, silk, fur, leather and hair; synthetic fibres such as fibres based on polyester, aliphatic polyamide (e.g. Nylon), aromatic polyamide (e.g. Aramid), polypropylene, polyethylene, polyvinyl chloride), fluorocarbon (e.g. poly(tetrafluoroethylene) PTFE) and polyurethane (e.g. Lycra™, Spandex™); fibres of mineral origin such as glass, carbon, ceramics and metal; and fibres of plant origin where any carboxylic acid groups have been chemically reacted so as to be unreactive such as cellulose acetate.
Antimicrobial active agents may be applied to non-cellulosic fibres by padding but there is no interaction between the non-cellulosic fibre and the antimicrobial active agent and consequently there is no durability to laundering or rinsing. Furthermore if antimicrobial active agents are used that may have adverse dermal effects, then such a system would not be feasible in applications requiring skin contact.
We have found that it is possible to immobilise antimicrobial active agents onto non-cellulosic fibres by means of self-crosslinkable resins without the need for ionic bonding or covalent crosslinking between the non-cellulosic fibre and the antimicrobial active agent.
In particular we have found that it is possible to immobilise antimicrobial active agents onto non-cellulosic fibres with very few or no active hydrogens. It is difficult to measure the concentration of active hydrogens on a fibre however a closely related property is the degree of hydrophilicity of a fibre. The hydrophilicity of fibres may be
defined using a number of parameters including the acid value of the fibre and or the
moisture regain of the fibre.
The measurement of acid values is described in "Comprehensive Cellulose
Chemistry" D. Klemm, B. Philipp, T. Heinze, U. Heinze and W. Wagenknecht, Volume 1,
Fundamentals and Analytical Methods, Wiley-VCH, 1998, ISBN 3-527-29413-9. The
technique used for the measurement of acid values of fibres is described below.
Moisture regain is the quantity of water picked up by a totally dry fibre and is
detailed in ASTM D2495 and D1909. The technique used for the measurement of
moisture regain is described below.
!
According to the present invention there is provided a composition for inhibiting the
growth of microorganisms on non-cellulosic fibres having a moisture regain of 5%
comprising:
i) 1 to 50 wt% of at least a self-crosslinkable resin;
ii) 0.25 to 20 wt% of at least a catalyst;
iii) 0.1 to 4.0 wt% of at least an antimicrobial active agent, reactive with the
resin;
iv) 98.65 to 26 wt% of water;
wherein i) + ii) + iii) + iv) = 100%.
Preferably the non-cellulosic fibres have a moisture regain 4.5%, more
preferably 4.0%, most preferably 3.0%, especially 2.0% and most especially 1.5%.
According to an alternative embodiment of the invention there is also provided a
composition for inhibiting the growth of microorganisms on non-cellulosic fibres having an
acid value of 5 mmol/kg comprising:
i) 1 to 50 wt% of at least a self-crosslinkable resin;
ii) 0.25 to 20 wt% of at least a catalyst;
iii) 0.1 to 4.0 wt% of at least an antimicrobial active agent, reactive with the
resin;
iv) 98.65 to 26 wt% of water
Preferably the non-cellulosic fibres have an acid value 4mmol/kg, more
preferably 3mmol/kg and most preferably 2 mmol/kg.
Preferred non-cellulosic fibres are synthetic fibres. Most preferably non-cellulosic
fibres include polyester, polyamide (Nylon), polypropylene, polyurethane (Lycra™,
Spandex™) and cellulose acetate.
Preferably the composition comprises 1 to 40 wt%, more preferably 2 to 20 wt%
and most preferably 3 to 12 wt% of at least a self-crosslinkable resin.
Preferably the composition comprises 0.25 to 10 wt%, more preferably 0.5 to 5
wt% and most preferably 0.75 to 3 wt% of at least a catalyst.
Preferably the composition comprises 0.2 to 4.0 wt%, more preferably 0.2 to 3.0
wt% and most preferably 0.4 to 1.6 wt% of at least an antimicrobial active agent reactive
with resin.
Preferably the composition comprises 60 to 98 wt% of water, more preferably 75 to
97 wt% and most preferably 80 to 95 wt% of water.
Preferably the weight ratio of self-crosslinkable resin to antimicrobial active agent
reactive with the self-crosslinkable resin is in the range of from 1:1 to 20:1 more preferably
in the range of from 1:1 to 15:1 and most preferably in the range of from 2:1 to 10:1.
The self-crosslinkable resin of the invention may be based on formaldehyde
condensates with urea or melamine which may be additionally modified to reduce
undesirable free formaldehyde levels. (Free formaldehyde gives rise to unpleasant
odours and may cause skin reactions). Additional formaldehyde condensates include
ethylene urea, benzoguanamine thiourea and acetoguanamine.
Suitable self-crosslinkable resins may be described as amino resins, more
preferably etherified amino resins and most preferably comprise urea-formaldehyde and
melaime formaldehyde resins, and in particular methylated and butylated ureaformaldehyde
and melamine-formaldehyde resins.
Self-crosslinkable resins that have ethylene incorporated and that release lower
levels of formaldehyde are preferred and include dimethyloldihydroxyethylene urea
[DMDHEU] and dihydroxydimethylene urea [DHDMEUJ. The remaining hydroxyl groups
of such self-crosslinkable resins may be further etherified with butyl or methyl groups to
still further lower free formaldehyde levels and such self-crosslinkable resins are often
known as formaldehyde-free resins.
Preferably urea-formaldehyde resins are utilised due to having a lower
crosslinkable density resulting in improved handling.
Preferably very low and most preferably formaldehyde-free resins are utilised.
Self-crosslinkable resins for use in accordance with the present invention (but not
limited there to) are available from commercial suppliers, under the following trade names
as shown in Table 1 below:
(Table Removed) To initiate the self-crosslinking reaction of the resin a catalyst is required. Suitable
catalysts include metal chloride catalysts such as magnesium chloride and ammonium
chloride; ammonium sulphate; ammonium salts of strong acids such as formic acid, boric
acid, phosphoric acid, oxalic acid and amine hydrochloride catalysts such as
polyhexamethylene biguanide [PHMB] hydrochloride, where the chloride ions act as a
catalyst However it is preferred to have an added catalyst (that is not PHMB). If PHMB
is used as a catalyst then amount used for component ii) and iii) are still as described
above. Preferably the catalyst is selected from the group consisting of MgCI2; ammonium
chloride; ammonium sulphate; ammonium salts of formic acid, boric acid, phosphoric acid,
oxalic acid; and or mixtures thereof.
Catalysts may contain additives such as citric acid. The function of additional
additives may be to increase the cure rate, reduce yellowing and or mop up any released
formaldehyde.
Antimicrobial active agents are used to inhibit the growth of microorganisms such
as bacteria, fungi, viruses, algae, yeasts and protozoa. Suitable antimicrobial active
agents for use in the present invention are agents with reactive hyroxyl or amine groups
that are covalently reactive with the self-crosslinkable resin. Examples include but are not
limited to quaternary ammonium salts, biguanide and monoguanide type antimicrobial
active agents, phenolics, alcohols and 2-bromo-2-nitropropane-1,3-diol. Preferably the
antimicrobial active agent is selected from the group consisting of quaternary ammonium
salts, biguanides, monoguanides, and or mixtures thereof.
Polyhexamethylene biguanide hydrochloride may therefore be used in both
capacities, i.e. the chloride ions as a catalyst and the polyhexamethylene biguanide part
as an antimicrobial active agent.
Preferably the antimicrobial active agents are selected from biguanides and
monoguanides.
Preferably the biguanide comprises at least two biguanide units of Formula (1):
—NH—C— NH— C—NH—
NH NH
Formula (1)
linked by a bridging group which contains at least one methylene group. The bridging
group preferably includes a polymethylene chain, optionally incorporating or substituted by
one or more hetero atoms such as oxygen, sulphur or nitrogen. The bridging group may
include one or more cyclic moieties which may be saturated or unsaturated. Preferably,
the bridging group is such that there are at least three, and especially at least four, carbon
atoms directly interposed between two adjacent biguanide units of Formula (1).
Preferably, there are not greater than ten and especially not greater than eight carbon
atoms interposed between two adjacent biguanide units of Formula (1).
The biguanide may be terminated by any suitable group, such as a hydrocarbyl
group, a substituted hydrocarbyl group, an amine group or a cyanoguanidine group of the
Formula (2):
—NH—C—NH—CN
NH
Formula (2)
When the terminating group is hydrocarbyl, it Is preferably alkyl, cycloalkyl, aryl or
aralkyl. When the hydrocarbyl group is alkyl it may be linear or branched but is preferably
linear. Preferred alkyl groups include C-alkyl. Examples of preferred alkyl groups
include for example methyl, ethyl, n-propyl, isopropyl, rvpentyl, n-butyl, isobutyl, terf-butyl
and n-octyl.
When the hydrocarby! group is cycloalkyl, it is preferably cyclopropyl, cyclopentyl
or cyclohexyl. When the hydrocarbyl group is aralkyl, it preferably contains from 1 to 6,
more preferably 1 or 2 carbon atoms in the alkylene group attaching the aryl group to the
biguanide. Preferred aralkyl groups include benzyl and 2-phenylethyl groups.
Preferred aryl groups include phenyl groups. When the terminating group is
substituted hydrocarbyl, the substituent may be any substituent that does not exhibit
undesirable adverse effects on the microbiological properties of the polymeric biguanide.
Examples of such substituents are aryloxy, alkoxy, acyl, acyloxy, halogen and nitrite.
When the biguanide contains two biguanide groups of Formula (1) the biguanide is
a bisbiguanide. The two biguanide groups are preferably linked through a polymethylene
group, especially a hexamethylene group.
The terminating groups in such bisbiguanides are preferably Co-alkyl which may
be linear or branched and optionally substituted aryl, especially optionally substituted
phenyl. Examples of such terminating groups are 2-ethylhexyl and 4-chlorophenyl.
Specific examples of such bisbiguanides are compounds represented by Formula (3) and
(4) in the free base form:
Formula (3)
and
C4H9—CH—CH2—NH—C—NH—C—NH-(CH2)3-
C2H5 NH NH
-J 2
Formula (4)
The biguanide preferably contains more than two biguanide units of Formula (1)
and is preferably a linear polymeric biguanide which has a recurring polymeric chain
represented by Formula (5) or a salt thereof:
—X—NH—C—NH—C—NH—Y—NH—C-NH—C—NH—
NH NH NH NH
Formula (5)
wherein X and Y represent bridging groups which may be the same or different and in
which together the total of the number of carbon atoms directly interposed between the
pairs of nitrogen atoms linked by X plus the number of carbon atoms directly interposed
between the pairs of nitrogen atoms linked by Y is more than 9 and less than 17.
The bridging groups X and Y preferably consists of polymethylene chains,
optionally interrupted by hetero atoms, for example, oxygen, sulphur or nitrogen. X and Y
may also incorporate moieties which may be saturated or unsaturated, in which case the
number of carbon atoms directly interposed between the pairs of nitrogen atoms linked by
X and Y is taken as including that segment of the cyclic group, or groups, which is the
shortest. Thus, the number of carbon atoms directly interposed between the nitrogen
atoms in the group
—NH-CH2-0 O-CH2-NH—
is 4 and not 8.
The linear polymeric biguanides having a recurring polymer unit of Formula (5) are
typically obtained as mixtures of polymers in which the polymer chains are of different
lengths. Preferably, the number of individual biguanide units of Formulae (5a) and (5b) is
together from 3 to about 80,
—X—NH—C—NH—J—NH— and — Y—NH—C-NH— C—NH—
NH NH NH NH
Formula (5a) Formula (5b)
The preferred linear polymeric biguanide is a mixture of polymer chains in which X
and Y are identical and the individual polymer chains, excluding the terminating groups,
are of the Formula (6) or a salt thereof:
- -(CH,)-TV 2/66— NH—CH— NH—C|(—NHNH
NH
Formula (6)
wherein n is from 4 to 20 and especially from 4 to 18. It is especially preferred that the
average value of n is about 16. Preferably, the average molecular weight of the polymer
in the free base form is from 1100 to 4000.
The linear polymeric biguanides may be prepared by the reaction of a
bisdicyandiamide having the Formula (7):
CN-NH-C-NH-X-NH-C-NH-CN
II II
NH NH
Formula (7)
with a diamine H2N-Y-NH2, wherein X and Y have the meanings defined above, or by the
reaction between a diamine salt of dicyanamide having the Formula (8):
(H3N+-X-N+H3)(N-(CN)2)2
Formula (8)
with a diamine H2N-Y-NH2, wherein X and Y have the meanings defined above. These
methods of preparation are described in GB patent numbers 702,268 and 1,152,243
respectively, and any of the polymeric biguanides described therein may be used in the
present invention. As noted hereinbefore, the polymer chains of the linear polymeric
biguanides may be terminated either by an amino group or by a cyanoguanidine group
This cyanoguanidine group can hydrolyse during preparation of the linear
polymeric biguanide yielding a guanidine end group. The terminating groups may be the
same or different on each polymer chain. A small proportion of a primary amine R-NH2,
wherein R represents an alkyl group containing from 1 to 18 carbon atoms, may be
included with the diamine H2N-Y-NH2 in the preparation of polymeric biguanides as
described above. The primary amine acts as a chain-terminating agent and consequently
one or both ends of the polymeric biguanide polymer chains may be terminated by an
-NHR group. These -NHR chain-terminated polymeric biguanides may also be used. The
polymeric biguanides readily form salts with both inorganic and organic acids. Preferred
salts of the polymeric biguanide are water-soluble. When the polymeric biguanide is
represented by a compound of Formula (3) in the free base form, a preferred water
soluble salt is the digluconate. This is commercially available from Avecia Limited under
the trademark Vantocil™ CHG. When the polymeric biguanide is a mixture of linear
polymers represented by Formula (6) in the free base form, the preferred salt is the
hydrochloride.
It is especially preferred that the polymeric biguanide used in accordance with the
present invention is a mixture of linear polymers,'the individual polymer chains of which,
excluding the terminating groups, are represented by Formula (6) in the hydrochloride salt
form. This poly(hexamethylenebiguanide) compound is commercially available from
Avecia Limited under the trademark Reputex™ 20.
Poly(C2.18-hydrocarbyl mono guanidine)s ("PMG") are distinguished from PHMB by
the fact that they contain mono guanidine groups whereas PHMB contains no mono
guanidine groups and instead contains biguanide groups of formula
-NHC=(NH)NHC(=NH)NH-.
The PMG preferably comprises a plurality of groups of Formula (10) and/or
groups of Formula (11) or salts thereof:
each m independently is 0 or 1;
each Z independently is a C2.i8-hydrocarbyl group;
A and B are hydrocarbyl groups which together comprise a total of 3 to 18 carbon
atoms;
each R independently is hydrogen, optionally substituted alkyl or optionally
substituted alkoxy.
Preferably each m is 0.
The hydrocarbyl groups in the PMG and represented by Z, A and B are optionally
interrupted by one or more hetero atoms or groups and optionally carry one or more
substituents other than hydrogen. Preferred interrupting atoms and groups are -O-, -S-,
-NH-, -C(=O)-and phenylene. Preferred optional substituents are hydroxy; C^-alkoxy;
halo, especially chloro or bromo; nitro; amino; substituted amino; and acid groups,
especially carboxy, sulpho and phosphate.
Preferably the hydrocarbyl groups in the PMG and represented by Z are C2.18-
alkylene (more preferably C -alkylene, especially C^ralkylene, more especially Cr
alkylene); Crarylene, more preferably Ce-io-arylene, especially phenylene or
naphthylene; C^rarakylene (more preferably C7.irarylene, especially benzylene or
xylyene); or a combination thereof, optionally interrupted by one or more -O-, -S-, -NH- or
-C(=O)- groups.
Preferably the hydrocarbyl groups represented by A and B are each independently
Ca-e-alkylene, optionally interrupted by one or more -O-, -S-, -NH- or -C(=O)- groups, with
the proviso that A and B comprise a total of 3 to 12 carbon atoms, preferably 3 to 6 carbon
atoms, more preferably 3 or 4 carbon atoms. In an especially preferred embodiment one
of A or B is -CHa- or -(CH2)r and the other is -(CH2)2-, more especially both A and B are
-(CH2)2-.
Examples of preferred -hydrocarbyl groups represented by Z include
-CH2C6H4CH2-, -CH2OC6H4OCH2-, -CH2OC6H10OCH2-, -(CH2)3O(CH2)3- and
-(CH2)2S(CH2)r.
Examples of particularly preferred -hydrocarbyl groups represented by Z include
-(CH2)6, -(CH2)8-r -(CH2)12-, -CH2CH(-CH3)(CH2)4CH3, 1,4-, 2,3- and 1,3-butylene, 2,5-
hexylene, 2,7-heptylene and 3-methyl-1 ,6-hexylene,
It is preferred that all groups represented by Z are the same and are C -alkylene,
more preferably C4-i2-alkyIene, especially C-alkylene, more especially 1,6- hexylene.
Preferably each R independently is H, C-alkyl, C-alkoxy or C-alkoxy-OH,
more preferably H or methyl, especially H.
Preferably the PMG consists essentially of groups of Formula (1 0).
Preferably all groups represented by R are the same.
More preferably all groups represented by R are H.
The nature of the terminating groups on the PMG is not believed to be critical.
Preferred terminating groups on the PMG are amino and guanidino.
In view of the foregoing preferences the PMG preferably comprises one or more
groups of Formula (12) or salts thereof:
wherein:
n is 2 to 50, preferably 3 to 25.
Preferably the PMG is in the form of a salt. Preferred salts are those with organic
or inorganic acids, especially water-soluble salts, for example the gluconate, acetate or
phosphate salt.
The PMGs may be prepared by the reaction of guanidine hydrochloride with a
diamine, for example of the formula H2N-Y-NH2, HN(-A-) (-B-)NH or with a mixture of such
diamines, wherein Z, A and B are as defined above.
It is to be understood that the PMG may also contain small amounts of repeating
units other than repeat units of Formula (10) and (11). However it is preferred that the
PMG consist essentially of or consists of repeat units of Formula (10) and/or (11) and
terminating groups.
Examples include polyhexamethylene monoguanide such as SKAN B™ available
from SK Corp, Korea and poly(oxyethylene)guanide hydrochloride such as Akacid™
available from POC, Austria.
A suitable example of a non-polymeric monoguanide includes n-docylguanide
hydrochloride.
The composition may be diluted with water, aqueous solvents, organic solvents
and or mixtures thereof before application to the non-cellulosic fibres. Preferably the
composition may be diluted with water and or alcohols, in particular glycols, which are
water-miscible and have a low volatility and more preferably the composition may be
diluted with water.
Optionally the composition of the present invention may also include dyes;
deodorant; UV-absorbents; non-crosslinkable resins; softeners; wicking agents; water
repelling agents; antistatic agents; stain repelling agents; lubricants such as
polytetrafluoroethylene (PTFE) and other additives well known to the person skilled in the
art in the textile industry.
In a second embodiment of the present invention there is provided a method for
inhibiting the growth of microorganisms on non-cellulosic fibres having a moisture regain
of 5% and or acid value of 5 mmol/kg comprising stages:
A) contacting the fibres with a composition comprising:
i) 1 to 50 wt% of at least a self-crosslinkable resin;
ii) 0.25 to 20 wt% of at least a catalyst;
iii) 0.1 to 4 wt% of at least an antimicrobial active agent, reactive with the
resin;
iv) 98.65 to 26 wt% of water;
wherein i) + ii) + iii) + iv) = 100%;
B) optionally drying the fibres contacted with the composition; and
C) curing the fibres contacted with the composition to effect crosslinking of the resin.
The. compositions according to the first aspect of the invention may be applied to
the non-cellulosic fibres (or yarns or fabrics made thereof) by any of the wet finishing
techniques known in the art for example spraying, dipping or padding processes. Padding
involves application of a composition to materials either by passing material through a
bath and then through squeeze rollers or by simply passing through squeeze rollers, the
lower one of which is partially or wholly immersed in the composition. Such techniques
can be used in a single-dip, single squeeze operation or can be more complicated (for
example, double dip, double-nip padding, or multiple dip, single nip, etc). For woven
material such as bedding and towelling the composition is preferably applied by padding
the compositions onto the rolls of the woven material. A further wet application technique
involves the use of a spray or dribble bar to apply the composition to a moving bed of
loose fibres or a composite non-woven material.
After contacting the fibres with composition, excess liquid is removed by for
example squeezing followed by a curing state to cause the self-crosslinkable resin to
cross-link and to effect reaction between the antimicrobial active agent and the selfcrosslinkable
resin. Preferably the antimicrobial active agent is covalently reactive with
the resin. Preferably the curing stage is carried out at temperatures in the range of from
100 to 180°C, more preferably in the range of from 140 to 180°C and most preferably in
the range of from 140 to 160°C.
Obviously the exact cure time and temperature depend on the exact device used,
however the cure time is preferably in the range of from 30 seconds to 5 minutes.
According to a third aspect of the invention there are provided non-cellulosic fibres
having a moisture regain of £ 5% and or an acid value of. 5mmol/kg carrying a
composition comprising:
(a) 1 to 10 wt% by weight of the non-cellulosic fibres of at least a selfcrosslinkable
resin; and
(b) 0.1 to 1 wt% by weight of the non-cellulosic fibres of at least an
antimicrobial active agent reacted with the resin.
According to a fourth aspect of the present invention there are provided noncellulosic
fibres having a moisture regain of treated with a composition according to the first aspect of the present invention.
According to a fifth aspect of the present invention there is provided the use of a
composition according to the first aspect of the present invention in the treatment of noncellulosic
fibres having a moisture regain of The invention is further illustrated by the following examples wherein all references
are to parts by weight, unless otherwise stated.
Test methods
Moisture Regain
The. standard test method for moisture regain for cotton and cotton blends is
described in ASTM D2495, and is used for the non-cellulosic fibres described herein.
Moisture regain is defined as the amount of water in a material specimen determined
under prescribed conditions and expressed as a percentage of the mass of the water-free
material specimen. In essence the fibre specimens are weighed, dried in an oven until a
constant weight is reached and then the difference between the original mass and the
oven-dry mass is calculated as a percentage.
Typical commercial moisture regain values are given in ASTM D1909 and are:
wool (13.6%), silk (11%), Rayon (11%), cotton (8.5%), nylon (polyamide) (4.5%),
polyester (0.4%), acrylic (1.5%), polyurethane (Spandex) (1.3%), polypropylene (olefin)
(0.0%), polyvinyl chloride (Vinyon) (0.0%) and fluorocarbon (Teflon) (0.0%).
In the examples below a polyester fibre with a moisture regain of 0.4% was used.
Acid Values
The acid value of a fibre was determined by the uptake of PHMB.
8g of the fibre to be tested was immersed in 120g of an 80ppm PHMB solution (in
distilled water) and was stirred at 40°C for one hour. This is known as exhaustion.
The ratio of solution to fibre is known as the liquor ratio and in this method the
liquor ratio is 120/8 = 15.
The UV/visible spectrum of PHMB solution was measured at 235 nm before and
after exhaustion of the fibre. From a calibration graph the concentration of PHMB was
calculated before and after exhaustion.
The acid value of the fibre is given by equation 1:
Acid value (mmol/kg) = difference in PHMB concentration (ppm x liquor ratio (Eq. 1)
molecular weight of PHMB
Typical acid values are cotton (30 mmol/kg), viscose (60 mmol/kg), nylon (1.6 mmol/kg,
polyester (red, knitted 0.91 mmol/kg), polyester (blue, woven 0.57 mmol/kg).
In the examples below a polyester fibre with an acid value of 1.07 mmol/kg was
used.
Levels of antimicrobial active agents
Determination of levels of antimicrobial active agents with cationic groups, such as
PHMB on treated fibres was carried out by staining with Eosin Y.
Eosin Y test solution
A stock solution of Eosin Y was prepared by dissolving Eosin Y [15g of 80%
2',4',5',7'-tetrabromofluorescein disodium salt indicator grade available from Aldrich
Chemical Co.] in distilled water [1500cm3] and then further diluted to 2500cm3 with
distilled water.
200cm3 of the stock solution of Eosin Y prepared above was mixed with distilled
water [1500cm3] and sodium citrate [100g] was added. After complete dissolution of the
sodium citrate the solution was further diluted to 2000cm3 with distilled water to give a
Eosin Y test solution.
Staining procedure
A sample of the fibre to be tested (about 0.2g) was weighed accurately, placed in a
30cm3 vial and 100 times the weight (of the fibre) of Eosin Y test solution was added,
before sealing the vial and placing the vial on rollers at ambient temperature for 20
minutes.
The fibre sample was removed, rinsed in cold water and then placed in about
800cm3 of warm water and stirred for 5 minutes. This rinsing step was repeated a further
three times before the fibre samples were dried at 50°C.
Estimation of treatment levels
Measurement of the reflectance spectrum of stained fibre samples were carried
out using an X-Rite SP62 spectrometer. Alternatively a direct visual comparison of the
stained fibre sample with a range of stained reference samples may also be used to give
an acceptable estimate of the treatment level.
Assessment of antimicrobial activity
The AATCC 100 Test Method (1998) is a quantitative test for measuring the
bacterial population on for example a sample of textile material made up of non-cellulosic
fibres, and hence determining the antimicrobial efficacy. The procedure may be
summarised as follows. A culture of Klebsiella pneumoniae shaken overnight in nutrient
broth was diluted to approximately 1 x 105 cells/cm3 in 5% sterile physiological saline
solution. Two samples (each 0.5g) were taken from each piece of treated cloth, and
inoculated with 1cm3 of the suspension of Klebsiella pneumoniae. After inoculation, one
sample of the cloth was immediately neutralised with 100cm3 of neutraliser solution (CEN
standard neutraliser), and shaken vigorously for 60 seconds. The surviving cells were
counted by a serial dilution pour plate technique on nutrient agar plates, using saline
solution as diluent. The other inoculated sample was incubated at 37°C for 24 hours. The
neutralising and counting technique was then carried out as described above. Further
details of this technique can be found in AATCC Technical Manual, published by the
American Association of Textile Chemists and Colorists, PO Box 12215, Research
Triangle Park, North Caroline 27709, USA.
All counts were measured as colony forming units per cm3 (cfu/cm3).
Washing of fibres
Fabric samples made up of non-cellulosic fibres were washed using a standard
method of the Home Laundry Consultative Council (HLCC), a United Kingdom group
responsible for setting guidelines on washing of textile articles. Samples were taken at
regular intervals and up to 25 washes were carried out.
The method used was 6A at 40°C. The details of the wash are as follows:
1. 6 minutes wash at 40°C
2. 2 rinses of 3 minutes at 15°C
3. 1 rinse of 2 minutes + spin of 1 minute
4. 1 rinse of 2 minutes + spin of 2 minutes
The washing machine was a Wascator FOM 71. Each wash used 2kg of sample,
with 48g of ECE Reference Detergent + 12g perborate bleach.
Example 1 (ED
Texchem™ 2700 is a modified DMDHEU resin supplied by Texchem Dyestuffs Ltd of
Rochdale UK as an aqueous solution with 66% solids content and was used as supplied.
Condensol™ FC is a 50% aqueous solution of MgCI2 and other components, and was
used as supplied by BASF pic, Ludwigshafen, Germany.
Reputex™ 20 is a 20% aqueous solution of PHMB supplied by Avecia Ltd of Blackley, UK
and was used as supplied.
A mixture was prepared of 100g Texchem™ 2700, 30g Condensol™ FC and 40g
Reputex™ 20 and made up to 1000 cm3 with water, and charged to the trough of a
laboratory pad/mangle. A piece of 100% polyester fabric, size 25cm x 25cm was fed
through the pad, and squeezed to give a pick-up of 50%. The fabric was then air dried,
and heat cured at 160°C for 3 minutes, rinsed in warm water and air dried.
Example 2 (E2)
Baypret™ R is a modified DMDHEU resin supplied by Bayer AG of Leverkusen, Germany
as an aqueous solution with 60% solids content and was used as supplied.
A mixture was prepared of 100g Baypret™ R, 30g Condensol™ FC and 40g Reputex™ 20
and made up to 1000 cm3 with water, and charged to the trough of a laboratory
pad/mangle. A piece of 100% polyester fabric 25cm x 25cm was fed through the pad, and
squeezed to give a pick-up of 50%. The fabric was then air dried, heat cured at 160°C for
3 minutes, rinsed in warm water and air dried.
Comparative Example 1 (CE1)
Untreated 100% polyester fabric. This example is a control sample with no additional
treatment.
17
Comparative Example 2 (CE 2)
40g Reputex™ 20 made up to 1000cm3 with water was charged to the trough of a
laboratory pad/mangle. A piece of 100% polyester fabric, 25cm x 25cm was fed through
the pad, and squeezed to give a pick-up of 50%. The fabric was then air dried, heat cured
at 160°C for 3 minutes, rinsed in warm water and air dried. This example is a control
sample with antimicrobial active agent but no self-crosslinkable resin or catalyst.
The fabric was washed up to 25 times at 40°C.
Comparative Example 3 (CE 3)
A mixture was prepared of 100g Texchem™ 2700 and 30g Condensol™ FC and made up
to 1000cm3 with water and charged to the trough of a laboratory pad/mangle. A piece of
100% polyester fabric, 25cm x 25cm was fed through the pad, and squeezed to give a
pick-up of 50%. The fabric was then air dried, heat cured at 160°C for 3 minutes, rinsed in
warm water and air dried. This example is a control sample with self-crosslinkable resin
and catalyst but no antimicrobial active agent.
Comparative Example 4 (CE 4)
A mixture was prepared of 100g Baypret™ R and 30g Condensol™ FC and made up to
1000cm3 with water and charged to the trough of a laboratory pad/mangle. A piece of
100% polyester fabric, 25cm x 25cm was fed through the pad, and squeezed to give a
pick-up of 50%. The fabric was then air dried, heat cured at 160°C for 3 minutes, rinsed in
warm water and air dried. This example is a control sample with self-crosslinkable resin
and catalyst but no antimicrobial active agent.
AH of the fabrics were washed up to 25 times at 40°C, and the durability to
washing was measured using the Eosin Y staining technique and the results are given
below in Table 2:
(Table Removed) When the antimicrobial active agent was applied without any self-crosslinkable
resin a pink stain was obtained. However after a single wash the stain was lost showing
clearly that the antimicrobial active agent was not durable to washing.
The level of anti-bacterial activity was measured as described above and the
results are given in Table 3 below: (Table Removed)








WE CLAIM:
1. A composition for inhibiting the growth of microorganisms on non-cellulosic fibres
having a moisture regain of ≤ 5% and/or an acid value of ≤ 5 mmol/kg comprising;
i) 1 to 50 wt% of at least a self-crosslinkable resin;
ii) 0.25 to 20 wt% of at least a catalyst;
iii) 0.1 to 4 wt% of at least an antimicrobial active agent, reactive with the resin;
iv) 98.65 to 26 wt% of water;
wherein i) + ii) + iii) + iv) = 100%.
2. A composition as claimed in any one of the preceding claims where the noncellulosic
fibres are selected from the group consisting of polyester, polyamide, polypropylene,
polyurethane and cellulose acetate.
3. A composition as claimed in any one of the preceding claims where the self-crosslinkable
resin is an amino resin.
4. A composition as claimed in claim 3 where the self-crosslinkable resin is a formaldehyde
condensate with urea or melamine.
5. A composition as claimed in claim 4 where the self-crosslinkable resin is selected from
dimethyloldihydroxyethylene urea and dihydroxydimethylene urea.
6. A composition as claimed in any one of the preceding claims wherein the catalyst is
selected from the group consisting of MgCl2; ammonium chloride; ammonium sulphate;
ammonium salts of formic acid, boric acid, phosphoric acid, oxalic acid; poly
(hexamethylene biguanide) hydrochloride and or mixtures thereof.
7. A composition as claimed in any one of claims 1 to 5 where the catalyst is selected from
the group consisting of MgCl2 ammonium chloride; ammonium sulphate; ammonium
salts of formic acid, boric acid, phosphoric acid, oxalic acid; and or mixtures thereof.
8. A composition as claimed in any one of claims 1 to 6 where the catalyst is poly
(hexamethylene biguanide) hydrochloride.
9. A composition as claimed in any one of the preceding claims where the antimicrobial active agent is selected from the group consisting of quaternary ammonium salts, biguanides, monoguanides, and or mixtures thereof.

Documents:

3038-delnp-2006-Abstract (20-11-2009).pdf

3038-delnp-2006-abstract.pdf

3038-delnp-2006-Claims (20-11-2009).pdf

3038-DELNP-2006-Claims-(25-01-2011).pdf

3038-delnp-2006-claims.pdf

3038-delnp-2006-Correspondence-Others (20-11-2009).pdf

3038-DELNP-2006-Correspondence-Others-(18-02-2011).pdf

3038-DELNP-2006-Correspondence-Others-(18-08-2010).pdf

3038-DELNP-2006-Correspondence-Others-(25-01-2011).pdf

3038-delnp-2006-correspondence-others-1.pdf

3038-delnp-2006-correspondence-others.pdf

3038-delnp-2006-Description (Complete) (20-11-2009).pdf

3038-delnp-2006-description (complete).pdf

3038-delnp-2006-Form-1 (20-11-2009).pdf

3038-delnp-2006-form-1.pdf

3038-delnp-2006-form-18.pdf

3038-delnp-2006-Form-2 (20-11-2009).pdf

3038-delnp-2006-form-2.pdf

3038-delnp-2006-Form-3 (20-11-2009).pdf

3038-DELNP-2006-Form-3-(18-02-2011).pdf

3038-DELNP-2006-Form-3-(18-08-2010).pdf

3038-delnp-2006-form-3.pdf

3038-delnp-2006-form-5.pdf

3038-delnp-2006-GPA (20-11-2009).pdf

3038-delnp-2006-gpa.pdf

3038-delnp-2006-pct-101.pdf

3038-delnp-2006-pct-105.pdf

3038-delnp-2006-pct-210.pdf

3038-delnp-2006-pct-220.pdf

3038-delnp-2006-pct-224.pdf

3038-delnp-2006-pct-237.pdf

3038-delnp-2006-pct-304.pdf

3038-delnp-2006-pct-308.pdf

3038-delnp-2006-Petition-137 (20-11-2009).pdf


Patent Number 246160
Indian Patent Application Number 3038/DELNP/2006
PG Journal Number 08/2011
Publication Date 25-Feb-2011
Grant Date 17-Feb-2011
Date of Filing 26-May-2006
Name of Patentee ARCH UK BIOCIDES LIMITED
Applicant Address ENGLAND AND WALES, WHELDON ROAD, CASTLEFORD, WEST YORKSHIRE WF 10 2JT, UK
Inventors:
# Inventor's Name Inventor's Address
1 JOHN DAVID PAYNE 5 HARGREAVES COURT LUMB, ROSSENDALE LANCASHIRE BB4 9QA UK
2 JOHN EDWARD YATES 966 OLDHAM ROAD, THORNHAM, ROCHDALE GREATER MANCHESTER OL 11 2BS UK
PCT International Classification Number D06M 13/432
PCT International Application Number PCT/GB2004/004738
PCT International Filing date 2004-11-10
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 0327693.8 2003-11-28 U.K.