Fabric softening composition

2~12~ -- 1 -- C7149 FABRIC SO~ ;NlNG COMPOSITION This invention relates to a fabric so~tening composition and to a process for treating fabrics th~rewith.

Fabri~ softening compositions are used in textile finishing and laundering processes to impart properties such as softness and a pleasant feel or "han~le" to fabrics, and are used particularly in the rinsa stage of the laundering process immediately after the laundry articles have been washed in a w~hin~ ~ machine.

A large n-lrh~r of proposals has been made for the formulation of fabric softenin~ compositions, most of th~se involving the use of an aqueous dispersion of a cationic surfactant, for instance a quaternary ammonium salt or an imidazolinium salt, as the active component or as part of it.

It is known that GB-A-2039556 that fabric softening compositions can be formulated to comprise a dispersion of cationic surfactant together with free ~atty acid which functions as a nonionic sur~actant~ .

2~ ~12~ - 2 - C7149 The above compositions based on dispersions of cationic surfactants are non-Newtonian in character. In composition~ intended for use by consumers in the home the viscosity (or strictly the apparent viscosity3 of the composition is an important factor in its acceptability to the consumer, the more viscous compositions being perceived as being of higher quality than the more mobile ones. Manu~acturers therefore attempt to produce a product which is as viscous as po~sible without being so lo viscous that problems are created elsewhere, such as in pouring or dispensing characteristics. In compositions intended for automated dispensing in w~hin~ machines, a low but tightly controlled viscosity is desirable, which again is difficult to achieve if the composition behaves unpredictably during manufacture and subsequent ageing.

EP-51983 discloses a process for the manufacture of a shear-thir.ning fabric softening composition, with good control of final viscosity~ comprising the steps of se~uentially or simultaneously:

(i) forming an aqueous dispersion of a cationic surfactant, having a viscosity less than the final viscosity; and (ii) thickening the composition to the final viscosity with a nonionic or weakly anionic polymeric thickener.

The thickener is selected from guar gum, polyvinylacetate, polyacrylamide, or a mixture of guar gum and xanthan gum cont~in;ng no more than 10~ by weight of xanthan gum.

The polyacrylamides which are specifically referred to are the less anionic polyacrylamides.

Quaternised guar gum was stated to be unsuitable.

_ 3 _ C7149 The essence o~ the process of EP-519~3 is to form a dispersion which is less viscous than is desired, and then thicken it with a polymeric thickener.

We have now found that a further class of polymeric materials is especially suitable as a thickener ~or fabric conditioning compositions.

These materials provide dispersions the viscosity of which is relatively stable, and which do not bring with them any disadvantage lo which would make the product unsatisfactory ~or tr~ating fabrics.

These thickeners are polymeric subs~ces comprising a hydrophilic backbone and at least two hydrophobic moieties per molecule.

Accordingly the present invention relates to an aqueous fabric conditioning composition comprising a fabric softener and a polymeric material, said material comprising mole~ules with a hydrophilic backbone and at least two hydrophobic groups per molecule attached to the hydrophilic ~ackbone, with the proviso that the polymeric material is not a hydrophobically modi~ied nonionic cellulose ether.

For the purpose of this invention only combinations of softener materials and polymers ar~ claimed which have a higher viscosity in the presence of the polymer than in 3 the absence of the polymer. It is bslieved that only polymPric molecules having at least two hydrophobic moieties contxibute to the thickening e~fect. For practical purposes, however, generally a reaction mixture o~ polymeric molecules will be used, in that case it is not necess~ry that in such a mixture the molecules contain on average two hydrophobic moieties; satis~actory 2 ~ 2 ~ - 4 - C7149 result~ can also be obtained when the average is less than two, provided that a significant part o~ the molecules compris~ two or more hydrophobic moieties. It is however preferred that polymeric reaction mixtures are used which comprise on average two or more hydrophobic moieties per molecule.

Preferably the number of hydrophobic groups attached to the hydrophilic backbone is relatively smallO Preferably the hydrophobic groups constitute less than 5% by weight of the polymer, more pre~erred between 0.5 and 2% by weight of the polymer. These relatively small numbers of hydrophobic groups ensure that the molecules remain relatively water soluble. Preferred polymeric thickeners according to the invention have a solubility in water at 25~C of more than 0,01% by weight, preferably more than 0.5% by weight, most preferred betwePn 0.5 and 25% by weight.

Preferred hydrophobic groups are linear or branched alkyl or alkenyl groups, preferably having a chain length of less than 40, more preferably between 8 and 24 carbon atoms.

The polymeric thickeners for use in fabric conditioners according to the invention preferably have a nonionic or cationic hydrophilic backboneO Preferably the polymeric thickeners are hydrophobically modified nonionic polymer~.

Pre~erred hydrophobically modified nonionic polymers are based on polyoxyalkylene or polyvinylalcohol hydrophilic backbones, to which a small number of alkyl ~-ou~s have been attached. ~xamples of these materials are:

2 0 ~ 2 ~ _ 5 _ C7149 (i) copolymers of ethylene oxide andJor propylene oxide with ~mall amounts of C~-C24 sid~ chains, for instance ~aving the basic formula:

HO ~ ( ~H2CH2~ ~n ( CpH2pcH2o )~ - CHcH2OH : r ~, 3 R3 ~2 (ii) Hydrophobically modified poly (ethylene oxide and/or propylene oxide/ureth~nes) for instance of the following formula:

:l O O H R N - C - (CH~CH20) n (CpH2pCH20)m L J R3 (iii) alkyl substituted poly (vinyl) alcohols, for instance of the following formula:

: OH HO - CH2 ~ )n ~ CH CH2 OH ~3 2 Wherein:

p = 1 t~ 4 preferably 1 or 2 n~m = greater than 10 m = If p is greater than 1, m is such that thP group involved constitutes less than 50 mole %, prefarabl~ less than 25 mole ~ of the polymer.

2 ~ 2 ~ ~ 6 ~ ~7149 Rl e a C8-C24 linear or branched alkyl or alkenyl ~2 hydrogen or a C8-C24 linear or bra~ched alkyl or alkenyl R - a ;n; ~ of two R1 groups which can be S substituted at any CH2 group along the polymer backbone.

Hydropho~ically modified poly (ethylene oxide and/or propylene oxide/urethanes) according to formula 5ii) are marketed by UNION CARBIDE under the UC~R SCT tr~ rk for the thickening of latex systems and generally have a molecular weight in the region of 40,000. Up till now it has not been recognised that these materials can advantageously be incorporated in fabric conditioning systems which are of a totally different nature than the latex systems in which the materials have been incorporated up till now.

Also a surprising aspect of the present invention is that the level of thickener material, necessary to obtain the desired thickening effect is far less when using a polymeric material as now claimed for use in softensr systems than by using other thickener ~aterials which have up till ncw been used for the thi~kenin~ of fabric conditioning compositions.

Dep~n~;ng upon the viscosity required, the polymeric material will be present in the composition o~ the lnvention in an amount of from 0.008 to 0.80% by weight, preferably ~rom 0.01 to 0.30% by weight of the composition.

The preferred molecular weight of the thickener 35 materials to b~ used is preferably above 15,000 more preferred from 20,00.0 to 1,000,000 more preferred from 2 ~ 2 ~ - 7 - ~71~9 25,000 to 100,000, espec~ally preferred from 30,000 to 7~,000.

The fabric softener for use in the fabric 5 conditioning composition according to the invention can be any ~abric substantive cationic, nonionic or amphoteric material suitable for so~ening fabrics.

Preferably the softening material is a cationic lo material which i5 water-insoluble in that these materials have a solubility in water at pH 2.5 and 20~C of less than 10 g/l. Highly preferred materials are cationic quaternary ammonium salts having two C12 24 hydrocarbyl ch~inc~., Well-known species of substantially water-insoluble guaternary ammonium compounds have the formula f R R + 1 ~ / 3 N \ X / Rz R4 ~ ~f wherein R1 and R2 represent hydrocarbyl groups from about 12 to about 24 carbon atoms; R3 and R4 represent : 30 hydrocarbyl yLUU~s containing from 1 to about 4 carbon atoms; and X is an anion, preferably selected from halide, methyl sulfate and ethyl sulfate radicals.

Representative examples of these quaternary 35 softeners include ditallow ammonium chloride;

ditallowdimethyl ammonium methyl sulfate; dihex~decyl 2~1 2~ - 8 - C7149 dimethyl ammonium chloride; di(hydrogenated tallow) dimethyl ammonium methyl sulfatej dihexadecyl diethyl ammonium chloride; di(coc~nut) dimethyl ammonium chloride. Ditallow dimethyl ammonium chloride, di(hydrogenated tallow) dimethyl ammonium chloride, di(coconut3 dimethyl ammonium chlGride and di~coconut) dimethyl ammonium methosulfate are preferred.

Other preferred cationic compounds include those materials as disclosed in EP 239 910 ~P~G), which is included herein by reference.

In this specification the expres~ion hydrocarbyl group refers to alkyl or alXenyl groups optionally substituted or interrupted by functional groups such as -OH, -O-, -CONH, -COO-, etc.

Other preferred materials are the materials of the formula o R - C - O - CH -CH CH2 CH2-OH N Il / \ CH3$04R - C - O - CH - CH2 CH3 R5 being tallow, which is available from Stepan under the tradename Stepantex VRH 9O : and 2~12~ _ g _ C714 R6COOCH2 ~CH--CH2N R8RgRloX ~7COO where R~, Rg and R1o are each alkyl or hy~loxyalkyl groups containing from 1 to 4 carbon atomst or a benzyl group. R6 and R7 are each an alkyl or alkenyl chain containing from 11 ~o 23 carbon atoms, and X is a water soluble anion, substantially free of the corresponding monoester.

Another class of preferred water-insoluble cationic materials are the hydrocarbylimidazolinium ~alts believed to have the formula:

CH2 CH2 N C2H4 N C R11 A 2s ~ C / R12 R14 wherein R13 is a hydrocarbyl group cont~ n; ~ from 1 to 4, preferably 1 or 2 carbon atoms, Rl1 is a hydrocarbyl group containing from 8 to 25 carbon atoms, R1~ i~ an hydrocarbyl group containing from 8 to 25 carbon atoms, R1~ is an hydrocarb~l group containing from 8 to 25 20~ ~12~ - 10 - C7149 carbon atoms and R12 is hydrogen or an hydrocarbyl containing from 1 to 4 carbon atoms and A is an anion, preferably a halide, methosulfate or ethosulfate.

Preferred imidazolinium salts include l-methyl-1(tallowylamido-~ ethyl -2-tallowyl- 4,5,-dihydro imidazolinium methosulfate and l-methyl 1lpalmitoylamido) ethyl -2-octadecyl-4,5- dihydroimidazolinium chloride.

Other use~ul imidazolinium materials are 2-heptadecul-1-methyl-1- (2-stearylamido)ethyl~imidazolinium chloride and 2-lauryl-1hydroxyethyl-1-oleyl-imidazolinium chloride. Also suitable herein are the imidazolinium fabric softening components of US patent No. 4 127 489, incorporated by 15 reference. , Preferably the level of softening material in a composition according to the invention is from ~-75 weight %, preferably from 2-60% by weight more preferred from 2 to 15% by weight of the compositions.

The compositions may also contain preferably, in addition to the CAtiOniC fabric softener, other non-cationic fabric so~teners, such a6 nonionic or amphoteric ~abric softeners.

Suitable nonionic fabric softeners include glycerol esters, such as glycerol monostearate, fatty alcohols, ~uch as stearyl alcohol, alkoxylated ~atty alcohols Cg-C24 fatty acids and lanolin and derivatives ther~of.

Suitable materials are disclosed in European Patent Applications 88 520 (Unilever PLC/NV case C1325, 122 141 (Unilever PLC/NV case C1363) and 79 746 (Procter and Gamble), the disclosures of which are incorporated herein by reference. Typically such materials are included at a 2 ~ - 11 - C7149 level within the range of from 1-75%, preferably from 2-60%, more preferxed from 2 to 15% by weight of the composition.

S The compositions according to the invention may also contain preferably in addition to cationic fabric softening agents, one or more amines.

The term "amine" as used herein can refer to (i~ amines of formula R15 R16 R (I) 17 R15, R16 and Rl7 are defined as below;

(ii) amines of formula .

~ . ~18 ~20 R1~ N (CH~)n N R21 (II) ~ n Rl~, R19, R20 and R21, m and n are defined as below.

20~ 2~ - 12 - C7149 (iii) imidazolines o~ formula CH~ CH2 lo N C / N ~C2H4 - N ~ R11 \ ~12 ~14 III R11, R12 and R14 are defined as above (iv) condensation products formed fr~m the reaction of fatty acids with a polyamine selected from the group consisting of hydroxy alkylalkylenediamines and dialkylenetriamines and mixtures thereof. Suitable materials are disclosed in European Patent Application 199 332 (Procter and Gamble), inc~rporated herein by reference.

.

When the amine is of the formula I above, R15 is a C6 to C24, hydrocarbyl group, Rl6 is a C1 to C24 hydrocarbyl group and R17 is a r1 to C10 hydrocarbyl group. Suitable amines include those materials from which the quaternary ammonium compounds disclosed a~ove are deri~ed, in which R15 is Rl, R1~ is R2 and R17 is ~3.

Preferably, the amine is such that ~oth R15 and R16 are C6-C20 alkyl with C16-C1~ being most preferred and with R17 a~ C1 3 alkyl, or R15 is an alkyl or alkenyl group with at least 22 carbon atoms and R16 and R12 are C1 3 2 ~ 2 ~ ~- 13 - C7149 alkyl. Preferably these amines are protonated with hydrochloric acid, orthophosphoric acid (OPA), C1 5 carboxylic acids or any other similar acids, for use in the fabric conditioning compositions of the invention.

When the amine is of formula II above, R18 is a C6 to C24 hydrocarbyl group, R19 is an alkoxylated group of ~ormula -(CH2CH20)yH, where y is within the range from 0 to 6, R20 is an alkoxylated group of formula -(CH2CH20)zH where ~ is within the range from O to 6, and is preferably 3. When m is O, it is preferred that R18 is a ~16 to C22 alkyl and that the sum to~al of z and y is within the range from 1 to 6, more preferably 1 to 3.

When m is 1, it is preferred that R18 is a C16 to C22 alkyl and that the sum total of x and y and z is within the range from 3 to 10.

Representative commercially available materials of this class include Ethomeen (ex Armour) and Ethoduomeen (ex Armour).

Preferably the amines of type (ii) or (iii) are also protonated for use in the fabric conditioning compositions of the invention.

When the amine is of type (iv) given above, a particularly preferred material is . .

-' 2 g~ - 14 - ~7149 11\ j22 H / R2 3 N\ rJ/ \~' P~24 C ~ P'24 lo where R~2 and R23 are divalent alkenyl ch~in~ having ~rom 1 to 3 carbon atoms, and R24 is an acyclic aliphatic hydrocarbon chain having from 15 to 21 carbon atoms. A commercially available material of this class is Ceranine lS HC39 (ex Sandoz).

Mixtures of the amines may also be used. When present amine materials are typically included at a level within the range of from 1-75%, preferably 2-60~ more preferred 2 to 15% by weight of the composition.

optionally compositions according to the invention may also comprise one or more amine oxides of the ~ormula:

R25 R28 30 26 N (CH2)q N R27 0 0 r wherein R25 is a hydrocarbyl group containing 8 to 24, preferably 10 to 22.carbon atoms, R26 is an alkyl group 2~ - 15 - C7149 containing ~ to 4 carbon atoms or a group of ~ormula (CH2CH20)VH, v is an integer from 1 to 6, R27 is either R25 or R26' R28 ir R26, r is 0 of 1 and q is 3.

S ~he invention is particularly advantageous if the amine oxide contains two alkyl or alkenyl groups each with at least 14 carbons atoms, such as dihardened tallow methyl amine oxide, or one alkyl or alkenyl group with at least 22 carbon atoms.

When present such materials are lo typically included at a level of from 1-75, preferably 2-60 more preferred 2 to 15~ by weight of the composition.

Preferably, the compositions of the invention contain substantially no anionic material, in particular no anionic surface active material. If such materials are present, the weight ratio of the cationic fabric softening agent to the anionic material should preferably be more than 5:1.

The composition can also contain one or more optional ingredients selected ~rom 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 acid ~the pH of the compositions are preferably less than 5.0), rewetting agents, viscosity modifiers such as electrolyutes, ~or exa~ple calcium chloride, antigelling agents, perfumes, perfume carriers, fluorescers, colourants, hydrotropes, antifoaming agents, antiredeposition agents, enzymes, optical brightening agants, opacifiers~ stabilisers such as guar gum and polyethylene glycol, emulsifiers, anti-shrinking agents, anti-wrinkle agents, fabric crisping agentsl anti~spotting agents, soil-relea~e agents, germicides,.linear or branched silicones, 2 ~ 2 ~ - 16 - C714g ~ungicides, anti-oxidants, anti-corrosion agents, preservatives such as Bronopol ~Trade ~ark), a co ercially available form of 2-bromo-2-nitropropane-1, 3-diol, dyes, bleaches and bleach precursors, drape imparting agents, antistatic agents and ironing aids.

These optional îngredients, if added, are each present at levels up to 5% by weight of the composition.

The pH of the composition is preferably 5 or below, or 1 adjusted thereto.

Fabric conditioning compositions according to the invention may be prepared by any conventional method for the preparation of dispersed softener systems. A well-known method for the preparation of such dispersed systems involves the preheating of the active ingredients, ~ollowed by formation of a pre~dispersion of this material in water of elevated temperature, and diluting said systems to ambient temperature systems.

Zo The invention also provides a process for the manufacture o~ a shear-th;nn;ng fabric conditi~ner, comprising the steps of sequentially (a~ forming an aqueous dispersion of a softener having a viscosity of 1PSS than the final viscosity; and (b) thickening the composition to a final viscosity by including a polymeric material comprising molecules with a hydrophilic backbone and at least two hydrophobic groups per molecule attached to the hydrophilic backbone, except where the polym~ric material is a hydrophobically modified nonionic cellulose ether.

20~ 2~ - 17 - C7149 The final viscosity of the composition will be chosen in accordance with the end-use desired, but will generally be between 10 and 200 mPas, preferably between 20 and 120 mPas at 25~C and 106 s-1.

s In use, the fabric conditioning composition o~ 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 concentration of the ~abric lo softener, in this liquor will be between about 10 ppm and 1,000 ppm. The weight ratio of the fabrics to liquor will ~enerally be between 40:1 and 4:1.

The invention will be further illustrated by means O~ the following examples.

EXAMPLE I Basic fabric conditioner compositions of the following compositions were prepared by the following process (i) charge water into a mixing vessel, heat to 65~C and add dye (ii) heat cationic/nonionic active materials to 70~~ (iii3add heated active materials to water while stirring at 250 rpm (iv~ cool the product and add the appropriate ~ ~r ~n~ of thickPn~r (v) add perfume and formalin.

2~ - 18 - C7149 Composition A B Inqredients % by weiqht % by wei~ht Arquad 2HT 4.5 10.4 Pristerine 4916 (ex Unichema) -- 2.6 Preservative 0.02 0.02 Colouring 0.00055 0.00165 10 Phosphoric acid 0.03 Magnesium chloride -- 0.02 Perfume 0.21 0~55 Water balance Composition In~redients % bv weiqht Arquad 2HT 2.1 Non quaternised imidazoline(a) 4.2 Silicone(~) 0.2 Per~ume Dye ) 0.4 ~ Preservative : 5 Water balance (a) = Rewopon 1255 ex Rewo ~b) - a di methyl poly siloxane having a viscosi~y of 100,000 cSt at llOS 2 ~ 2 ~ -- 19 - C7149 Composition D Inqredient % by weiqht 5 ~rquad 2HT 3-43 Pristerine 4916 0.51 Formaldehyde 0.08 Colouring 0.0018 Perfume 0.25 lo Silicone(b) 0.029 Water balance The viscosity of the products at 25~C and 106 s-1 were measured in the presence and in the absence of 0.03% by weight of a polymeric thickener UCAR SCT 215 (ex Union Carbide), added in the form of a 25% solution as supplied.

The results were the following viscosity in mPas Composition o% UCAR 0.03% UCAR ~ 2s A 28 300 -B 33 231 : ~ 38.5 5~.5 D 35 43 EXAMPLE 2 Th~ viscosity of compositions D o~ Example I was measured after addition of various level~ of UCAR SCT-215 or Acrysol RM-825 (polyurethane polymer ex Rohm and Haas - 20 - C7149 added in the form of a 15% solution as supplied).

Viscosities were measured in mPas at 25~C at 110 s-l.

The r~sults were the following:

5 UCAR SCT-215 Weight % polymer viscosity (mPas 110s 1 0 33 0.02 38 0.04 63 0.06 92 0.10 145 ACRYSOL RM-8~5 Weight % polymer viscosity (mPas 110s-1) .

0 34 0.02 34 0.04 ~3 0O06 52 0.10 77