Note: Descriptions are shown in the official language in which they were submitted.
5~1
This invention relates to fabric treatment compositions and
to a method for treating fabrics in an aqueous bath such as
the final rinse after a washing process in order to improve
various properties of the fabric. In particular this
invention relates to compositions of the type disclosed in
our pending Canadian Patent Application Serial No. 257,084
filed on July 15, 1976.
It has been known for some years that fabrics can be made to
feel softer by treatment in a dilute solution or dispersion
of certain cationic quaternary ammonium derivatives and
rinse-additive compositions have been marketed for this
purpose. The invention disclosed in Canadian Application
Serial No. 257,084 of July 15, 1976 provides substantial
additional benefits by a combination of fabric conditioning
agents. These benefits may include some or all of: easier
ironing, anti-static properties, pleasanter feel of the
fabrics, soil release properties. It appears that recog-
nition of improved "ease of ironing" can arise from a com-
bination of at least three factors, namely fewer wrinkles
to be removed, wrinkles more easily removed (e.g. with less
weight upon the iron), or more completely removed, and less
effort required to slide the iron along the fabric.
"Pleasanter" feel can be consistently observed by experienced
judges, although it is not easy to define in words the sen-
sation or combination of sensations they like. Anti-static
and soil release properties improve the achieving and
maintaining of soil-free fabrics.
The combination of fabric conditioning agents referred to
above requires the presence of both a cationic quaternary
ammonium (or imidazolinium) derivative and a silicone.
~; '
~ ~25~
The silicone is defined as predominantly linear polymers ie.
poly dialkyl- or alkylaryl siloxanes. The alkyl groups have
l to 5 carbon atoms and are preferably methyl and may be
wholly or partially fluorinated. A limited degree of cross- ;~
linking is permissible and up to about 10 ~ by weight of
mono-alkyl or mono-aryl siloxanes may be present in the
silicones. Preferred silicones are polydimethyl siloxanes
having a viscosity at 25C in the range from 1000 to 200000
centistokes preferably 10000 - 120000 centistokes. Other
lQ preferred silicones are fluorinated silicones having a
viscosity at 25C of at least 100 centistokes.
As recited in the above discussed Canadian Application
Serial No. 257,084 the combination of a fabric substantive
quaternary ammonium textile softening compound and silicone
of the above type materially improves the substantivity of
the latter. It i6 postulated that this enhanced substantiv-
ity arised from a 'carrier' effect by means of which the
positively charged fabric softener molecules associate with
the silicone molecules and cause them to migrate to the
fabric surface. However, experiments have shown that the
distribution of this combination on the fabric is less than
optimum ie. some areas of fabric receive a high concentra-
tion of silicone while others receive very little if any
silicone.
It has now been found that the basic charge characteristics
of the silicone as used in the combination are important in
determining both the extent of deposition and the evenness
of distribution of the silicone and hence the properties of
a fabric treated therewith.
- 2 -
~11325~L3
This is illustrated in the following table in which the
adsorption of various silicone polymers on to cotton fabrics
from a 0.2% by weight aqueous solution of the silicone is
measured as a function of time.
wt. ~ adsorbed after:
2 10 15 30 minutes
Polydimethyl siloxane
nonionic emulsified
n = 1, OOOcs 10 10 10 lo
Polydimethyl siloxane
cationic emulsified
n = 28, OOOcs 65 85 86 88
n = 62,500cs 80 100 100 100
~ dipyridinium
polydimethyl siloxane ;
(High viscosity liquid `
M.wt. ~ 3000) 86 100 100 100
Amino functional silicone
(DC 929 supplied by Dow
Corning as a high 100 100 100 100
viscosity liquid and
comprising polydimethyl
silicone containing primary
and ~econdary amino groups of
d.s. 0. 008 )
It can be seen that silicones having cationic character show
an enhanced tendency to deposit.
As mentioned above, silicones found to be of value in provid-
ing fabric feel benefits have a predominantly linear charac-
ter and are preferably polydialkyl siloxanes in which the
alkyl group is most commonly methyl. Such silicone polymers
are frequently manufactured commercially by emulsion poly-
merisation using a strong acid or strong alkali catalyst in
~ the presence of a nonionic or mixed nonionic-anionic emul-
; sifier system.
3 ~ -
. - , -
~a .
.-', .
.
5~1
In combination with the cationic fabric softening agent,
anionic- or nonionic emulsified silicone polymers tend to
aggregate in dilute aqueous solution due to the attraction
between the negatively or non-charged emulsifier and the
positively charged fabric softening agent. However, the
provision of a silicone emulsion having a like charge to
that of the fabric softening agent would tend to reduce this
effect and a further reduction might be expected from the
tendency of the charged silicone droplets to repel each
other.
Accordingly, the present invention provides a textile
treating composition which is an aqueous dispersion com-
prising:
(a) a fabric substantive quaternary ammonium textile
softening compound having in its molecular structure
either two alkyl groups each having 12 to 20 carbon
atoms or one alkyl chain having 18 to 24 carbon atoms
or a fabric substantive quaternary imidazolinium
textile softening compound and
(b) a silicone component of cationic character as
hereinafter defined,
the weight ratio of the polysiloxane portion of component (b)
to the fabric substantive quaternary textile softening com-
pound of component (a) being in the range of 20:1 to 1:100.
Preferably the weight ratio of polysiloxane to the
quaternary textile softening compound is from about 2:1 to
to 1:10 especially from about 1:1 to 1:3.
For the purpose of the present application a silicone
component of cationic character is defined as being one of:
(a) a predominantly linear di Cl-C5 alkyl or Cl-C5
alkyl, aryl siloxane having a viscosity at 25~C
S~3L
of at least 100 centistokes, prepared by emulsion
polymerisation using a cationic surfactant as
emulsifier.
(b) an ~ di quaternised di Cl C5 alkyl or Cl-C5
alkyl, aryl siloxane polymer or
(c) an amino-functional di Cl-C5 alkyl or alkyl aryl
siloxane polymer in which the amino group may be
substituted and may be quaternised and in which the
degree of substitution (d.s.) lies in the range
0.001 to 0.1, preferably .01 - 0.075.
a) Cationlc_emulsion polymerised siloxanes
Cationic emulsion polymerised siloxanes are known in the
art and can be prepared by strong alkali or acid catalysis of
siloxane monomer(s) in the presence of a cationic emulsifying
agent. Hyde and Wehryl U.S. Patent No. 2,891,920 describes
general procedures for such polymerisations and Examples 1 -
6 of the patent provide specific teaching of the required
reaction conditions. The siloxane monomer can be any di lower
alkyl siloxane such as dimethyl, diethyl dipropyl, or ethyl
butyl siloxane or alkyl, aryl siloxane such as methyl, phenyl
siloxane or ethyl phenyl siloxane. However, the preferred
starting material for emulsion polymerisation is normally a
cylic trimer or tetramer of the desired siloxane.
The emulsifying agent can be any one of a wide range of
cationic surfactants such as:
Aliphatic fatty amines and their derivatives such as
dodecylamine acetate, octadecylamine acetate and acetates of
the amines of tallow fatty acids; homologues of aromatic
amines having fatty chains such as dodecylaniline; fatty amides
derived from aliphatic diamines such as undecylimidazoline;
fatty amines derived from disubstituted amines such as
- 5 -
.
5~
oleylaminodiethylamine; derivatives of ethylene diamine;quaternary ammonium compounds such as dioctadecyldimethyl
ammonium chloride, didodecyldimethyl ammonium chloride and
dihexadecyldimethyl ammonium chloride; amide derivatives of
amino alcohols such as ~-hydroxyethylstearyl-amide; amine
salts of long chain fatty acids; quaternary ammonium bases
derived from fatty amides of di-substituted diamines such as
oleylbenzylaminoethylene diethylamine hydrochloride; quater-
nary ammonium bases of the benzimidazolines such as methyl-
heptadecyl benzimidazol hydrobromide; basic compounds ofpyridinium and its derivatives such as cetylpyridinium chloride;
sulfonium compounds such as octadecylsulfonium methyl sulfate;
quaternary ammonium compounds of betaine such as betaine
compounds of diethylamino acetic acid and octadecylchloromethyl
ether; urethanes of ethylene diamine such as the condensation
products of stearic acid and diethylene triamine; polyethylene
diamines; and polypropanolpolyethanol amines.
The emulsifier is conventionally employed at a level of
1% - 10% by weight of the siloxane, more preferably 2~ - 5% by
weight.
The catalyst employed to polymerise the siloxane is
preferably an alkaline catalyst such as an alkali metal
hydroxide or a quaternary ammonium hydroxide of the formula
(R)4N OH. In such ammonium hydroxides the R groups can be
hydrogen or alkyl radicals such as methyl, ethyl, propyl,
butyl, isobutyl, decyl or octadecyl or a~alkyl radicals such
as benzyl or hydroxyalkyl radicals such as hydroxyethyl,
hydroxypropyl and hydroxybutyl.
Most preferably the catalyst is a quaternary ammonium
hydroxide having at least one radical of at least 12 carbon
atoms in chain length, such a material also serving as an
-- 6 --
~a :
- ' '
s~
emulsification agent. Long chain length alkyl quaternary
ammonium salts are also preferred as the emulsification agents,
particularly di-long chain alkyl di-lower alkyl quaternaries,
such as ditallowyl dimethyl ammonium chloride (DTDMAC),
available commercially from Armour Chemical Company as Arquad
2HT (Arquad is a Registered Trade Mark) and imidazolinium
derivatives such as methyl C18 alkyl amidoethyl, C18 alkyl
imidazolinium methosulphate, available commercially from
Ashland Chemical Company as Varisoft 275 (Varisoft is a
Registered Trade Mark).
The level of catalyst usage is dependent on the catalyst
type employed. Acid catalysts are conventionally used at high
levels, e.g., at 15% or more by weight of the aqueous phase of
the emulsion. Alkaline catalysts by contrast are used at
lower levels, e.g., from 0.001% to 10~, preferably from 0.1%
to 5% by weight of the siloxane monomer.
Emulsion polymerisation of dimethyl siloxane using -
DTDMAC as emulslfler
In a typical preparation, dichloro dimethyl siloxane
was first hydrolysed to form octamethyl cyclo tetra siloxane
using the method of Patnode and Wilcock in JACS 68 1946 pp
358 - 363. 15 grs of this material was then added to a mix-
ture of 131 grs of a 1% aqueous solution of ditallowyl
dimethyl ammonium chloride and 3.75 grs of tetrabutyl ammonium
hydroxide in the form of a 40% aqueous solution. The mixture
was stirred during addition of the ingredients by means of a
Silverson laboratory emulsifier mixer and, after addition was --
complete, the reaction mixture was subjected to 15 minutes
further agitation using an ultrasonic vibrator. After 18 hours
at 80C the poly dimethyl siloxane oil was precipitated from
the reaction mixture by addition of 500 mls of ethyl alcohol
and was then dxied with further alcohol before being heated
- 7 -
.~
.
5~
at 75C under a high vacuum to remove all volatile materials.The viscosity of the silicone was determined to be 22,000
centistokes by measurement of its rate of flow under gravity
between two marks on a calibrated tube. The time taken for
a given quantity to flow along the tube was converted to
viscosity using a calibration curve established with commer-
cial silicones of known viscosity.
Using the above-described polymerisation technique,
stable 10% emulsions of polydimethyl siloxane were achieved
and equivalent results were obtained when the procedure was
repeated using cetyl trimethyl ammonium bromide and the
imidazoline derivative Varisoft 475 respectively as the
emulsifier.
b) a-~ quaternised polysiloxanes
The preparation of ~,~ quaternised siloxane polymers can
be conveniently carried out using the method disclosed in
I.C.I. British Patent Specification No. 1,006,729. In this
technique a polysiloxane end-stopped with alkyl halide groups
in which the halogen atoms are separated from the nearest
silicon atoms by at least three carbon atoms, is reacted with
a tertiary amine to give an ~ quaternised siloxane polymer.
In order to provide the polysiloxane starting material a
solution polymerisation is normally carried out to give a
polymer of the appropriate molecular weight, and the poly-
merisation reaction is terminated by reaction with a ~-halo
alkyl dimethyl silanol.
As previously stated, the polysiloxane can be a poly di
(Cl-C5 alkyl)- or (Cl-C5 alkyl, aryl) siloxane, preferably a
polydimethyl siloxane and the tertiary amine can be any alkyl,
aryl or mlxed alkyl and aryl material. Examples include
trimethyl-amine, cetyl dimethyl-amine, pyridine, phenyl
8 - -~
.
1 3Lg;~5~
dimethyl-amine.
Preparation of a ~-~ dipyridinium polydimethyl siloxane
A typical preparation of this class of silicone polymers -
involved the polymerisation of 23.2 grs of octamethyl cyclo-
tetra siloxane in the presence of 0.9 mls of concentrated
sulphuric acid and 2.5 grs of 1,3-bis, 3-chloropropyl tetra-
methyl disiloxane. The mixture was shaken in a sealed flask
for 48 hours at room temperature, following which 5 mls of
water were added and the flask shaken for a further hour.
The resulting emulsion was split by addition of 50 mls of
diethyl ether and the organic layer was then washed twice
with 30 ml aliquots of distilled water, dried over sodium
bicarbonate and magnesium sulphate and filtered. Evaporation
of the filtrate to remove the ether left 23 grs of a clear oil
of viscosity 100 cs. NMR examination of the oil showed it to
correspond to a polymer having 36 siloxane units.
10 grs. of the ~ bis (3 chloropropyl) silicone prepared
above were then refluxed in 10 mls pyridine for 36 hours at
120C. Excess pyridine was distilled off under reduced
pressure leaving a brown viscous oil. This was then dis-
solved in toluene, washed with water and the toluene layer
dried and evaporated to remove the toluene. NMR spectral
analysis disclosed a level of proton activity corresponding
to 70-80% of the theoretical uptake of pyridine.
10% aqueous emulsions of the silicone product were
prepared by mechanical emulsification using an ethoxylated
linear alcohol emulsifying agent (Dobanol 45E4, a Cl4-Cl5
linear alcohol tetra ethoxylate supplied by Shell Interna-
tional Chemicals Limited) at a level of 20% by weight of
the siloxane.
_ 9 _ . .:
~i5 , ' . .
~ .
.
5~
c) Amino functional linear polysiloxanes
Amino functional linear polysiloxanes can be prepared by
the general method disclosed in sritish Patent Specification
No. 1,339,906 at page 3 lines 78-108, page 4 lines 1-65 and
page 3 lines 3-14. In this method, a hydrosiloxane is reacted
with an alkenyl group-containing tertiary amine in the presence
of a platinum catalyst in accordance with the equation
H PtCl
(Me3SiO)2 (SiMe20)x(SiMeHo)y + yCH2=CHR'NR2 2 6
(Me3SiO)2 (SiMe20)x(OSi(Me)R''NR2)y
wherein x = 10 to 100, y = 1 to 20, R is a methyl, ethyl or
phenyl group, R' is a direct linkage or a divalent organic
group free of aliphatic unsaturation containing 1-16 carbon
atoms and R" is a divalent organic group free of aliphatic
unsaturation containing 2-18 carbon atoms.
The product of the above reaction can then be quaternised
by further reaction with an alkyl halide or can be converted to
the hydrochloride by acidification with hydrochloric acid.
Preparation of ~olydimethyl siloxane substituted
with dimethylamlnopropyl groups
In a typical preparation 50 grs of dimethyl-methyl hydro-
gen siloxane copolymer containing approximately 76 dimethyl
siloxane units and 6 hydromethyl siloxane units was dissolved
in 50 mls toluene containing a trace of chlorplatinic acid.
The mixture was stirred under nitrogen at 80C, 5.18 grs of
N,N-dimethyl allylamine in 10 mls of toluene was added drop-
wise, holding the reaction temperature at 80-90C., and the
reaction mixture was stirred for a further 2 hours and then
cooled. Sodium carbonate was added to neutralise any remain-
ing acid and the mixture was filtered and rotary evaporated
to remove solvents, leaving a pale yellow fluid of low
viscosity. NMR analysis showed the formation of poly dimethyl
siloxane containing dimethylaminopropyl groups at a level
corresponding to a reaction completeness of 80~+, and a degree
of substitution (d.s.) of 0.06.
20 grs of the reaction product was stirred in lO0 mls of
a 1:1 mixture of dichloromethane and isopropanol and 1.3 mls
of concentrated HCl (11.21M) in 10 mls of the same solvent
mixture was added slowly at room temperature. ~ollowing
evaporation of the solvent a pale coloured solid was left and
NMR analysis showed this material as having a proton ratio
close to the expected value for the hydrochloride derivative
with no detectable level of the starting material. The
siloxane polymer was then made up into a 10% aqueous emulsion
using 20% based on the siloxane weight of a nonionic emulsifi-
cation agent (Dobanol* 45E4, a linear C14-C15 alcohol containing
4 moles of ethylene oxide supplied by Shell International
Chemicals Limited).
A similar experimental technique to the above was
employed to produce polydimethyl siloxanes having respectively
approximately 40 siloxane units and a d.s. of 0.04 and 72
siloxane units with a d.s. of 0.015.
Cationic softening compounds
~_ ,
The cationic softening compounds suitable include those
commonly used in rinse-added textile softening compositions.
These include quaternary ammonium salts of general formula
R2
~ N - X (I)
Rl R
wherein either (a) R2 and R3 (which may be the same or
different) represent methyl, ethyl, propyl or benzyl, and
either R and Rl each represent a straight or branched chain
alkyl group having 12 to 20 carbon atoms, or R represents a
-- 11 --
*Dobanol is a Registered Trade Mark
51~ ~
straight or branched chain alkyl group having 18 to 24 carbon
atoms and Rl represents methyl, ethyl, propyl or benzyl; or
(b) R2 and R3 together with the nitrogen atom form a 5- or
6-membered heterocylic ring and R and Rl are as defined in
(a); or (c) Rl, R2 and R3 together with the nitrogen atom
form a 5-membered or 6-membered heterocylic ring and R
represents a straight or branched chain alkyl group having
18 to 24 carbon atoms; and X is an anion. The long chain
alkyl groups may be derived from natural fats, e.g., coconut,
or more preferably tallow, or from petroleum or synthetically.
In a preferred group of salts of formula (I), R and R
each represent an alkyl group having 16 to 18 carbon atoms,
R2 and R3 each represent methyl, and X represents Cl , Br
OS03CH3 -
Other anions include nitrite, acetate and phosphate.
Specific examples of particularly preferred cationic
softening agents include the following:
-tallowtrimethyl ammonium chloride,
-tallowdimethyl (3-tallowalkoxypropyl) ammonium
chloride,
-ditallow dimethyl ammonium chloride,
-ditallow dimethyl ammonium methyl sulphate,
-eicosyltrimethyl ammonium chloride, and
-dieicosyldimethyl ammonium chloride.
Examples of other suitable cationic softening agents
suitable for use in the invention herein include the
following:
-ditetradecyldimethyl ammonium chloride, ~ -
-dipentadecyldimethyl ammonium chloride,
-didodecyldiethyl ammonium chloride,
-didodecyldipropyl ammonium chloride,
- 12 -
.. .. . .. . .. . .
s~
-ditetradecyldiethyl ammonium chloride,
-ditetradecyldipropyl ammonium chloride,
-ditallowdiethyl ammonium chloride,
-ditallow dipropyl ammonium chloride,
-tallowdimethyl benzyl ammonium chloride,
-tallowdiethyl benzyl ammonium chloride, -
-didodecyldiethyl ammonium acetate, . -
-tallowtrimethyl ammonium acetate,
-tallowdimethyl benzyl ammonium nitrite, and
-ditallowdipropyl ammonium phosphate.
Other cationic softening agents of formula (1) are
known and include variations wherein R and Rl can also
represent a phenyl radical or a hydroxy-substituted alkyl
of 1, 2 or 3 carbon atoms.
Many other cationic quaternary ammonium softening :
agents, which are useful herein, are known; for example,
alkyl [C12 to C20]-pyridinium chlorides, alkyl ~C12 to C20]-
alkyl [Cl to C3]-morpholinium chlorides, and quaternary
derivatives of amino acids and amino esters.
Cation quaternary imidazolinium compounds are also
suitable as softening agents in the compositions herein.
The most useful compounds generally conform to the formula
~ :'
l 7
H-l Cl - H O ~ x Q (II) ~ :
C r \ 2 4
R7
wherein R4 represents hydrogen or alkyl having 8 to 25,
preferably at least 15, carbon atoms, R5 represents alkyl
- 13 - :
5~
having 1 to 4, preferably 1 or 2, carbon atoms, R6 represents
alkyl having 1 to 4 earbon atoms or hydrogen, R7 represents
- alkyl having 8 to 25, preferably at least 15, carbon atoms
and X is an anion, preferably methyl sulphate or chloride.
Other suitable anions include bromide, acetate, nitrite and
phosphate. Particularly preferred are those compounds of
formula (II~ in which both R4 and R7 represent alkyl having
16 to 25 (especially 16 to 18 or 20 to 22) carbon atoms.
The concentration of the aqueous dispersions (by which
term is included solutions) which constitute the compositions
of the invention is not critical and is controlled by practical
considerations. Thus the dispersions should be concentrated
enough not to be wasteful in transit costs, yet should be
fluid enough to be poured and to disperse readily in a usage
bath. Usually a content of from about 1% to 20%, especially -
about 3-10%, by weight of components (a) and (b) together is
convenient. As stated earlier, the ratio of the siloxane
portion of component (b) to the quaternary softening agent of
component (a) should be in the ratio of 20:1 to 1:100 by
weight, preferably from 2:1 to 1:10 and most preferably from
1:1 to 1:5.
The aqueous dispersions may contain other components,
such as emulsifying aids, for instance low levels of the
order of about 1% by weight of nonionic surfactants to aid
dispersion of the usually poorly soluble cationic softeners.
A wide range of nonionic emulsifiers can be used for this
purpose such as those disclosed in German Patent Application
OLS 2500111 published July 17th, 1975. It is found that
use of emulsifiers is sometimes desirable to aid also the
dispersion of the silicones in the compositions of the
invention, especially when silicones of relatively high
viscosity are employed.
14 -
5~1
Highly preferred optional ingredients also include non-
ionic fabric treatment agents such as the fatty acid partial
esters of polyhydric alcohols or anhydrides thereof having
from 3 to about 8 carbon atoms in the alcohol and fatty acid
esters of Cl - C8 monohydric alcohols. The fatty acid esters
of the polyhydric alcohols should have at least 2 free (i.e.,
unesterified) hydroxyl groups and at least 1, more preferably
at least 2, fatty acyl groups.
The polyhydric alcohol portion of the ester can be
glycerol, diglycerol, xylitol, sucrose, erythritol, penta-
erythritol, sorbitol or sorbitan; sorbitan esters are
particularly preferred.
:
- 14a -
- ' : : ' ~ .
5~
The fatty acid portion of the ester normally comprises a
fatty acid having from 12 to 20 carbon atoms, typical examples
being lauric acid, myristic acid, palmitic acid, stearic acid
and behenic acid.
Amongst these esters, the most preferred are the glyceryl
esters of stearic acid, especially glyceryl monostearate, and
the sorbitan fatty acid esters, which are esterified
dehydration products of sorbitol.
These sorbitan fatty acid esters are disclosed in Canadian
Patent 1,074,96~, issued April 8, 1980. Nonionic fabric condi-
tioning materials of this type are commonly employed at levels
of 1 - 5% preferably 2 - 4% by weight of the composition.
Other preferred ingredients include pyrodextrins such as
British Gum and White dextrin and substituted dextrins such as
dextrin phosphates, cationic dextrins and dextrin pyrollidone
carboxylic acid, in which the degree of substitution is from
0.01 to 2.0 preferably 0.05 to 1.5. A preferred cationic
dextrin is a white dextrin that has been reacted with glycidyl
trimethyl ammonium chloride to provide a degree of substitution
(d.s.) in the dextrin molecule of from about 0.1 to 1Ø The
dextrins are used at levels of 0.5~ ~o 5~ by weight of the
compositions, preferably at levels of 1% to 3~.
Non-aqueous, water miscible solvents may be present, and
other viscosity controlling agents, such as low levels of
electrolytes. Other optional components include appropriate
optical brighteners, fungicides and germicides, colouring or
opacifying agents, and perfumes.
In use the compositions of the invention are normally
incorporated in an aqueous bath containing the ingredients of
the compositions in the ratios defined hereinabove, at a con-
centration such that there is present from about 20 to 1,000
parts per million by weight of components (a) and (b) together
of which at least 10 ppm is component (b). Preferably the bath
- 15 -
,
5~1
contains from about 50 to 200 ppm of components (a) and (b)together of which at least about 15 to 150 ppm is component
(b)-
The invention also embraces a method of treating textiles,and textiles when so treated, which method comprises steeping
them in such a bath.
The textiles may be steeped in such a bath and then dried
on any occasion, but it is envisaged that normally the treat-
ment will constitute the final rinse after a washing process.
EXAMPLES
Test Procedures
Clean test pieces of cotton or other fabric were treated
in a domestic washing machine. Either a whole standard load
was made up of test pieces or additional clean fabrics were
used to make up the load. The machine cycle was set so that
the load was subjected to gentle agitation (as for a wool
wash cycle) for about 20 minutes in a solution of the test
product in water, and was then spin-dried.
Wrinkling test
Treated test pieces were compared with a standard set
o 10 plastic simulated test pieces of different degrees of
wrinkling (American Association of Textile Chemists and
Colourists - Three dimensional durable press replicas for
use with AATCC Test 124). Number 10 graded perfect, Number
1 worst. A grade 5-7 was deemed to represent about that
degree of freedom from wrinkling at which a housewife might
be expected to consider ironing unnecessary.
Ease of Ironing test
This was judged by a panel of judges, employing a
Scheffé analysis to provide gradings (panel score units -
psu) and a "yardstick", i.e., least difference significant
- 16 -
~.
- ' '': '
~25~1
at 95% probability.
End Result test
A visual preference, graded as above in psu.
Softness test
A tactile preference, graded as above in psu.
Drying of Fabrics
The "spin-dried" test pieces were dried by hanging in
the laboratory (static drying) or in a tumbler dryer.
Comparison of silicone types
The performance of a conventional nonionic emulsion
polymerised silicone A* was compared to that of two cationic
silicone polymers B** and C*** by applying each to cotton
pieces in a rinse bath at 0.2% concentration. The cotton
pieces were dried and then graded for Ease of Ironing,
Ironed end result and Softness. The results are expressed
below in panel score units relative to the figures for
silicone A. -~
*A was a polydimethyl siloxane of viscosity 60,000 centistokes
prepared by emulsion polymerisation using a mixture of
nonionic and anionic emulsifiers.
**B was an amino functional silicone of molecular weight ~6500
containing ~75 dimethyl siloxane units and approximately six
siloxane units in which a methyl group was substituted by a
H2cH2NH3cl grouping-
***C was an ~,~-di pyridinium silicone of molecular weight
~3000.
B vs A C vs A Yardstick
Ease of ironiny+ 0.8 + 1.75 1.1
Ironed end result + 1.5 + 1.03 0.79
30 Softness + 0.7 + 0.35 0.78
- 17 -
. ~
5~
This test took place in the absence of a cationic
softener and demonstrates the advantages of the enhanced
deposition of the two cationic polymers.
Comparison of cationic softeners + silicones of
different emulsion type
A number of aqueous softening compositions were made
up as follows (percentages are by weight):
I 6% DTDMAC + 3% of silicone A
II 6% DTDMAC + 3% of silicone B
III 6% DTDMAC + 3% of a polydimethyl siloxane of viscosity
40,000 centistokes prepared by emulsion polymerisation
with a cationic emulsifier (DTMAC) present at a level
of 10% of the silicone.
Each composition was employed at 0.2% concentration in
a rinse step to treat terry cotton cloths, which were then
dried and graded for softness impression. The results in
panel score units (psu) are expressed below in terms of the
advantages for compositions II and III relative to composition
I.
II III
+ 0.4 + 0.8
+ 0.1 + 0.8
The yardstick for the tests, at the 95% conidence level,
was 0.8 psu so that Composition III can be seen to provide a
significant softness benefit relative to Composition I.
Comparison of silicones having different viscosities
The effect of silicone viscosity on the wrinkle grade,
ease-of-ironing grade and ironed-end-result grade of cotton
tea towels treated with compositions of the invention was
examined for a range of polydimethyl siloxanes prepared by
emulsion polymerisation using a cationic emulsifier.
- 18 -
5~
Seven aqueous compositions were made up, each containing6% DTDMAC and 3% of a silicone emulsion polymerised in the
presence of 1% DTDMAC on a silicone basis. The siloxane
polymers varied in viscosity from 1000 to 170,000 centi-
stokes. The compositions were applied at 0.2% concentration
to the fabrics simulating a final rinse treatment in a conven-
tional washing cycle and the treated fabrics were then air
dried and graded by a panel of judges. In such panel testing
a difference between fabrics of approximately 0.5 panel score
units (psu) in wrinkle grade is normally detectable by the
housewife, while for ease of ironing and ironing end result
a panel score unit difference of between 0.75 - 1.0 between
fabrics is generally necessary in order for a difference to
be noticeable.
The results are shown below, indexed to the grades
obtained with a cationic-emulsified silicone of viscosity
170,000 centistokes
Wrinkle Ease of Ironed
Grade Ironing end result
20170,000 0 o 0
100,000 + 0.2 0 + 0.5
40,000 + 0.3 + 0.1 - 0.2
20,000 + 0.4 + 0.8 + 1.2
8,000 + 0.6 + 0.7 + 1.7
3,700 + 0.6 + 1.1 + 2.1
1,000 + 0.5 + 0.8 + 1.3
It can be seen that performance for these parameters
improves with a reduction in viscosity from 170,000 cs to a
value in the range 3,000 - 20,000 cs with the optimum appear-
ing to lie in the range 3,000 - 8,000 cs.
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