Note: Descriptions are shown in the official language in which they were submitted.
~~2~~~2
- 1 - C7190
FABRIC SOFTENING COMPOSITION
The present invention relates to a fabric softening
composition and to a method for its preparation.
Specifically, the present invention relates to a fabric
softening composition for use in the rinse step of a
fabric washing process.
It has been proposed in EP 239 910 (PROCTER & GAMBLE)
to incorporate biodegradable quaternary ammonium compounds
in fabric softening compositions. US 3 915 867 (STEPAN)
discloses the use of N-methyl,N,N-di(~ -C acyloxy
14-18
ethyl) N- -hydroxy ethyl ammonium methosulphate in
softening compositions.
It is an object of the present invention to provide
fabric softening compositions which comprise biodegradable
quaternary ammonium compounds. It is a second object of
the invention to provide biodegradable fabric softening
compositions which are of acceptable stability. Further
objects of the invention are to provide fabric softening
compositions which can easily be prepared and which
provide surprisingly good softening to fabrics treated
therewith.
_ ~ 2021322
Accordingly, the present invention relates to a fabric softening
composition comprising:
(i) a quaternary ammonium material represented by the formula:
OOCR2
R1 N - (CHZ)n CH
Rl CH2 OOCR2
wherein each Rl group is independently selected from C1_4 alkyl,
alkenyl or hydroxyalkyl groups; and wherein each R2 group is
independently selected from C~2$ alkyl or alkenyl groups; and n is an
integer from 0-5
(ii) a C8_28 fatty acid material or a salt thereof.
The compositions of the invention may take a variety of forms such as
pastes, liquids, tablets, etc. and also they may be impregnated with
substrates,
for example for use in tumble dryers. Preferably, compositions of the
invention are liquids comprising an aqueous base, wherein the active
ingredients are dispersed.
Preferred quaternary ammonium materials and their methods of
preparation are, for example, described in US 4 137 180 (LEVER BROTHERS).
Preferably these materials comprise small amounts of the corresponding
monoester as described in US 4 137 180 for example 1-tallowoxy, 2-hydroxy
tyrimethyl ammonium propane chloride.
X2021322
-3-
Preferably, the le.~l of ester-linked quaternary ammonium
compounds is at least 1% by weight of the composition, more preferably more
than 3% by weight of the composition; especially interesting are compositions
of high active level, e.g. which comprise more than 8% of the ester-linked
quaternary ammonium compound. The level of ester-linked quaternary
* denotes trade mark
ammonium compounds preferably is
- 4 - C7190
less than 70% by weight of the composition, more
preferably less than 50%, typically from 3 to 30% by
weight of the composition.
The fatty acid material or salt thereof can be any
mono-, di- or tri-carboxylic acid comprising an alkyl or
alkenyl chain having from 8 to 28 carbon atoms or salts
thereof. Preferred fatty acid materials or their salts
may be represented by the formula:
R1COOR2
wherein R1 is a straight or branched alkyl or alkenyl
chain having from 8 to 28 carbon atoms, and wherein R2 is
hydrogen or a cation. Preferred cations are alkali metal
ions or alkali earth metal ions; more preferred are
sodium, potassium or calcium.
Preferred is the use of a non-saponified fatty acid
material. Especially preferred is the use of free fatty
acids having a chain length of from 12 to 18, such as
oleic acid, lauric acid, tallow fatty acid etc.
Preferably, the level of fatty acid material is more
than 0.1% by weight of the composition, more preferably
more than 0.2%; especially preferred are concentrated
systems comprising more than 0.5% of fatty acid material.
The level of fatty acid material will usually not exceed
50% by weight of the composition, more preferably the
level of fatty acid material is less than 30%, typically
from 0.5 to 10% by weight of the composition.
The weight ratio of ester-linked quaternary ammonium
materials to fatty acid materials is preferably from 10:1
202~.~22
- 5 - C7190
to 1:10, more preferably from 8:1 to 1:1, especially
preferably from 7:1 to 3:1.
The compositions of the invention preferably have a
pH of more than 2Ø For compositions containing free
fatty acids, the pH is preferably less than 5.0 to prevent
saponification of the fatty acids. For compositions
containing the salts of the fatty acid, preferably the pH
is 5.0 or more, more preferably between 5.0 and 8Ø
Compositions of the invention may, in addition to the
above described two ingredients, also comprise other
active ingredients such as further fabric conditioning
materials.
In selecting the optional ingredients it is preferred
to use materials which do not substantially affect the
biodegradability of the composition. Therefore it is
preferred to minimize the level of non-biodegradable or
less bio-degradable materials.
Preferably, the compositions of the invention do not
comprise large amounts of conventional non-ester-linked
quaternary ammonium comounds, more preferably the
compositions of the invention are substantially free of
these quaternary ammonium compounds.
Suitable conditioning materials for inclusion in
compositions of the invention comprise nonionic materials.
Suitable nonionic fabric softening agents includ glycerol
esters, such as glycerol monostearate, fatty alcohols,
such as stearyl alcohol, alkoxylated fatty alcohols,
C9-C24 fatty acids and lanolin and derivatives thereof.
Suitable materials are disclosed in European Patent
Applications 88 520 (Unilever PLC/NV - Case C1325),
CA 02021322 2000-08-08
- 5 - C7190
122 141 (Uni.lever PLC/NC - Case C1363) and 79 746 (Procter
& Gamble).
Other softening materials which may be incorporated
in a composition of the invention are amines, such as, for
instance, described in EP 332270 published September 13, 1989, or
biodegradable amphoteric softening materials such as, for instance,
described in EF~ 326213, published August 2, 1989.
Preferably, the amount of softening materials other
than the above mentioned ester-linked materials and fatty
acid materials is relatively low, i.e. the weight ratio of
other softener materials to the total of the two essential
softener components is preferably less than 2:1, more
preferably :Less than 1:1, most preferably less than 0.5:1.
The composition can also contain one or more optional
ingredients selected from non-aqueous solvents such as
C1-C4 alkanols and polyhydric alcohols, pH buffering
agents such as strong or weak acids, e.g. HCl, H2S04,
phosphoric, benzoic or citric acids, rewetting agents,
viscosity modifiers such as electrolytes, for example
calcium chloride, anti-gelling agents, perfumes, perfume
carriers, f:luorescers, colourants, hydrotropes,
anti-foaming agents, anti-redeposition agents, enzymes,
optical brightening agents, opacifiers, stabilizers such
as guar gum and polyethylene glycol, emulsifiers, anti-
shrinking agents, anti-wrinkle agents, fabric crisping
agents, anti-spotting agents, soil-release agents,
germicides, linear or branched silicones, fungicides,
anti-oxidants, anti-corrosion agents, preservatives such
as Bronopol (Trade Mark), a commercially available form of
2-bromo-2-nitropropane-1,3-diol, dyes, bleaches and bleach
precursors, drape-imparting agents, anti-static agents and
ironing aids.
20~13~2
- 7 - C7190
These optional ingredients, if added, are preferably
present at levels up to 5% by weight of the composition.
The liquid compositions according to the invention
may be prepared by a variety of methods. One suitable
method is to form a molten mixture of the ester-linked
quaternary ammonium materials and the fatty acid
materials, optionally in combination with other softening
materials, and adding this premix to water with stirring
to form a dispersion and thereafter adding any other
optional ingredients.
In use, the fabric conditioning composition of the
invention may be added to a large volume of water to form
a liquor with which the fabrics to be treated are
contacted. Generally, the total concentration of the
ester-linked quaternary ammonium compound and the fatty
acid compound in this liquor will be between about 30 ppm
and 1000 ppm. The weight ratio of the fabrics to the
liquor will generally be between 1:1 and 1:20.
The invention will be further illustrated by the
following Examples.
The softening performance of compositions A-C was
tested. Composition A is a commercially available fabric
conditioner (KUSCHELWEICH) containing 4.5% by weight of
dihardened tallow dimethyl ammonium chloride dispersed in
water, pH 2.7. Composition B is a 5% by weight dispersion
in water of Stepantex VRH 90; the pH of the product is
2.3. Composition C is a dispersion in water of 5%
Stepantex VRH 90 and 0.83% of hardened tallow fatty acid;
the pH of the product was 2.5.
CA 02021322 2000-08-08
- 8 - C7190
2.5kg loads of desized terry towelling cloths were
washed in an AEG *LAVAMAT 570 at 50°C with water of 24 FH
and 1008 of a commercially available washing powder
(PERSIL AUT01~1ATIC). Compositions A-C were added to the
last rinse cycle of the washing process in the amounts as
indicated. '.L'he cloths were line-dried and assessed for
softness by a trained panel of 9 persons by a round robin
test method. A higher softness score indicates a better
softness. The following results were obtained:
softening ma~:erfal dosage *1
4 Z
A 2.0 2.9 3.3
B 1.9 2.9 2.8
C 3.6 3.9 5.0
*) In grams of active material (cationic softener plus
optionally fatty acid) per rinse.
These results show a clearly better softening
performance :for composition C compared to compositions A
and B. This illustrates the surprisingly good performance
of compositions comprising a combination of ester-linked
quaternary a;mmonium compounds and fatty acid materials.
The softening performance of compositions DEF was
tested. Composition D is a commercially available fabric
conditioner (*COCCOLINO CONCENTRATE). The compositions
were prepared by heating the active ingredients until
molten and dispersing the molten active into demineralised
water at 70°C whilst stirring.
*denotes trade mark
CA 02021322 2000-08-08
- 9 - C7190
Component
E E
DTTMAPC * - 12.00 10.29
THTMAPC ** - 13.00 2.57
DHTDMAC *** 12.80 - -
Hardened tallow fatty acid 3.20 - 2.14
Isopropylalcohol 2.13 2.70 2.27
Water ------- balance ---------
* 1,2-ditallowoxytrimethyl ammonium propane chloride
prepared according to US 4 137 180
** 1-tallowoxy, 2-hydroxy trimethyl ammonium propane
chloride prepared according to US 4 137 180
*** dihardened tallow dimethyl ammonium chloride
40g loads of terry towelling test monitors were
washed in a *MIELE front loading automatic with a ballast
load of terry and polyester cotton to bring the total to
2.5kg. The load was washed with 1008 of New System Persil
Automatic at 60°C. 35m1 of the compositions D, E or F was
added during the final rinse. The monitors were line
dried and assessed for softness using a round robin paired
comparison protocol by an expert panel. A higher softness
score indicates a better softness. The following results
were obtained.
Composition Softness Score
D 0.00
E - 0.23
F + 1.00
*denotes trade Knark
202122
- 10 - C7190
A difference between compositions of 0.89 was
requried for a 95% significance.
These results show a better softening performance for
composition F compared to compositions D and E. This
illustrates the surprisingly good performance of
compositions comprising a combination of ester-linked
quaternary ammonium compounds and fatty acid materials.
EXAMPLE 3
The biodegradability of ester-linked quaternary
ammonium materials was compared to that exhibited by more
generally used quaternary ammonium materials such as
dihardened tallow dimethyl ammonium chloride by using a
modified STURM test as described in DECD Paris 1981 Test
Guideline 3018, Decision of the Council C(81)30 Final,
Consistent.with the requirements of official Journal of
the European Communities No. L251/179 C.5 BIODEGRADATION.
Essentially the test measures the amount of carbon dioxide
evolved from a sample undergoing biodegradation as a
percentage of the theoretical maximum.
% C02 evolved
DHTDMAC * 20%
Stepantex VRH 90 67.1 ~ 8.7 (8 determinations)
DTTMAPC ** 78.9 ~ 10.1 (10 determinations)
* dihardened tallow dimethyl ammonium chloride
** 1,2-ditallowoxy trimethyl ammonium propane chloride
These results show that ester-linked quaternary
ammonium materials suitable for use in compositions
according to the invention are more biodegradable than
- 11 - C7190
quaternary ammonium materials which are more generally
used.
