GB2230787A - Aqueous polysiloxane compositions and process for the treatment of textiles - Google Patents

Abstract

Aqueous compositions for the treatment of textiles comprise water having dispersed therein (A) an organic cationic compound, (B) a polydiorganosiloxane which is preferably linear and provided in the form of an emulsion, and (C) from 0.2 to 1 part by weight per part of Component (A) of a quaternary ammonium silane of the general formula (iii) R<3>3SiR<4>N<+)<R<5>)3X<-> in which each R<3> is alkyl, hydroxyl, alkoxy, alkoxyalkoxy or trimethylsiloxy, R<4> is a divalent aliphatic hydrocarbon linking the silicon and nitrogen atoms, each R<5> represents a monovalent hydrocarbon group, 1 or 2 groups R<5> having an aliphatic chain composed of on average from 8 to 18 carbon atoms and 1 or 2 groups R<5> having an aliphatic chain composed of not more than 5 carbon atoms and X<-> represents a monovalent anion. The compositions are useful as rinse cycle softeners giving also improved rewettability to treated textile fabrics.

Description

COMPOSITIONS AND PROCESS FOR THE TREATMENT OF TEXTILES This invention relates to a composition for the treatment of textiles and is concerned in particular with compositions which impart softness to textile fabrics. It also relates to a process for treating textiles with said compositions and to the treated textiles obtained thereby.

Compositions for imparting softness to textile fabrics and which are intended for application during or following laundering have been known and widely used for many years. Such materials are known as, for example 'fabric softeners' or 'fabric conditioning compositions' and are generally designed for application during the rinsing stage of the laundering operation. The primary active constituents of such compositions have ben cationic surface active compounds, for example the di(hydrogenated-tallow)dimethvl ammonium chlorides, diamido alkoxylated. quaternary ammonium compounds and quaternised amido imidazolines. Such compounds are generally poorly soluble in water and are often employed in conjunction with emulsifying aids to assist dispersion. Such compounds are also not easily biodegradable, their use giving rise to environmental concern.

It has been disclosed in British Patent Specification 1 549 180 that additional benefits e.g. easier ironing and pleasant handle can accrue if the cationic compound is applied to the fabric in conjunction with certain silicones. Preferred silicones for use according to G.B. 1 549 180 are stated to be those having a cationic character and which show an enhanced tendency to deposit on the fabric. The silicone should also have a viscosity of at least 100 mm2/s and less than 8000 mm2/s at 25"C. Although said compositions have represented a significant advance in the art of fabric softeners there has been a continuing search for improvements in properties such as the feel or drape of the treated fabric and rewettability; the latter property being of particular interest when the fabric is towelling.Compositions according to the above mentioned patent specification still use a relatively large amount of organic quaternary compounds.

We have now found that improved fabric conditioning compositions may be provided by using certain quaternary silanes in conjunction with organic quaternary compounds.

According to the present invention there is provided an aqueous composition for the treatment of textiles which comprises water having dispersed therein (A) an organic cationic compound which is substantive to water rinse on textile fibres, (B) a polydiorganosiloxane having units of the general formulae (i) R2R2SiOi and (ii) RaSiO4-a in which R is selected from the 2 group consisting of alkyl and aryl groups having up to 8 carbon atoms, R2 is selected from R groups and hydroxyl and a Is an integer with a value of from 0 to 2 and (C) from 0.2 to 1 part by weight per part of component (A) of a quaternary ammonium silane of the general formula (iii) R33SiR4N+(R5)3X in which each R is selected from the group consisting of alkyl groups having up to 5 carbon atoms in their chain, a hydroxyl group, alkoxy groups, alkoxyalkoxy groups having less than 12 carbon atoms and a trlmethylsiloxy group, R4 represents a divalent aliphatic hydrocarbon group having from 2 to 10 carbon atoms in its chain linking the silicon and nitrogen atoms and composed of carbon, hydrogen, optionally oxygen in the form of hydroxyl and optionally oxygen in the form of ether linkages, each R5 represents a monovalent hydrocarbon group, 1 or 2 groups R5 having an aliphatic chain composed of on average from 8 to 18 carbon atoms and 1 or 2 groups R5 having an aliphatic chain composed of not more than 5 carbon atoms and X represents a monovalent anion.

As Component (A) of the compositions of this invention there may be employed any organic cationic substance which is substantive to water rinse on textile fabrics and which is capable of imparting softness and/or lubricity to textile fabrics.

A large number of such substances is known and includes quaternary ammonium compounds such as (a) alkylmethyl quaternary ammonium compounds having either one C18-C24 alkyl chain or two C12-C30 alkyl chains, the long chain alkyl groups being most commonly those derived frcm hydrogenated tallow. Examples of such compounds are ditallowdimethyl ammonium chloride, ditallowdimethyl ammonium methyl sulphate, tallowtrimethyl ammonium chloride, dieicosyldimethyl ammonium chloride, tallowdimethyl(3-tallowalkoxypropyl)ammonium chloride, ditetradecyldimethyl ammonium chloride, didodecyldiethyl ammonium acetate and tallowtrimethyl ammonium acetate; (b) amido alkoxylated quaternary ammonium compounds.

Quaternary compounds of this type can be prepared from fatty acids or triglycerides and an amine e.g. diethylene triamine. The product is then alkoxylated with ethylene oxide or propylene oxide and quaternised with dimethyl sulphate. Compounds of type (b) can be represented by the formula

wherein M represents a fatty alkyl group typically C12 to C20, X represents for example C1, Br or the methyl sulphate group, z is 2 or 3 and c is an integer; (c) quaternised amido imidazolines. Compounds of this type can be obtained by heating the alkoxylated product of reacting an amine and a fatty acid or triglyceride as described for type (b) to effect ring closure to the imidazoline. This is then quaternised by reaction with e.g. dimethyl sulphate.An example of a type (c) compound is 2-heptadecyl-1-methyl-1-(2'-stearoyl amido-ethyl) imidazolinium methyl sulphate; (d) polyamine salts and polyalkylene imine salts e.g.

[C12H25NHCCH3)-CCH2)3-NH2C12H25++++[Cl]2, 2 [C18H37NH(CH3) (CH2)2 NH(C2H5)2] (CH3S04) 2 and a poly ethylene iminium chloride having about 10 ethylene imine units; (e) alkyl pyridinium salts e.g. cetyl pyridinium chloride.

The generally preferred organic cat ionic conditioning agents are those having long chain, fatty alkyl groups derived from tallow or hydrogenated tallow and the generally preferred class of softening agents are those of type (a), that is the alkylmethyl ammonium compounds.

Fabric conditioning agents which may be employed as component (A) of the compositions of this invention are well kr,oa.r. substances and have been widely described in the technical literature, see for example J. Am. Oil Chemists Soc., January 1978 (Vol 55), pages 118 - 121 and Chemistry and Industry, 5th July 1969, pages 893 - 903.

Component (B) is a polydiorganosiloxane compound which is preferably provided as an oil-in-water emulsion. Suitable poly diorganosiloxanes are those which can be provided in emulsions either by emulsion polymerisation or by mechanical emulsification. Preferred polydiorganosiloxanes are linear polymers, wherein a of formula (ii) has a value of 2. These preferred polymers have the average general formula (iv) RSiR2[OSiR]nOR2SiR, wherein R and R2 are as defined above and n is an integer. The groups R are preferably at least predominantly methyl but may include phenyl or other aromatic groups as aforesaid.Polydiorganosiloxanes in which at least substantially all R groups are methyl groups are preferably liquid polymers which have a viscosity of at least 1000 mm2/s at 25"C and preferably less than about 300,000 mrn2/s; preferably they have a viscosity of from 10,000 to about 200,000 mm2/s at 25"C, most preferably from 12,500 to 100,000 mm2/s at 25"C.

Polydiorganosiloxanes in which more than about 10% of the R groups are phenyl and less than 90% are alkyl groups preferably have a viscosity in the range of about 10 to about 1000 mm2/s at 25"C. Alternatively polydiorganosiloxanes of gum-like consistency may also be used in small proportions and are preferably supplied in a solvent consisting of low viscosity polydiorganosiloxes, e.g. cyclic polydimethylsiloxanes having on average 4 or 5 silicon atoms in the ring. The emulsion in which the polydiorganosiloxane is preferably provided may be made by mechanically emulsifying a polydiorganosiloxane of required viscosity according to methods which are well known in the art.

Polydiorganosiloxanes which may be thus emulsified are well known and man are commercially available. They may be prepared for example by the hydrolysis of halogenosilanes or by equilibration of cyclic diorganosiloxanes with monofunctional silanes.

Alternatively the emulsion may be made by emulsion polymerisation as is described for example in British Patent Specification 992 CS7. The latter method is particularly preferred for the higher viscosity liquid polydiorganosiloxanes. Emulsions made by the emulsion polymerisation technique are usually more stable and have a smaller particle size than the emulsions which are made by mechanical emulsification. Polydiorganosiloxanes made via the emulsion polymerisation technique may have a structure in which each R represents a hydroxyl group.

Emulsions which are particularly useful in the compositions of the present invention may have a solids content of up to about 75% but preferably contain from about 10% to about 40/é by weight polydiorganosiloxane. The polydiorganosiloxane (B) may be emulsified in water employing any suitable emulslỳing agent.

The nature of the surfactant is not critical; preferably it is cationic or nonionic. Examples of surfactants are aliphatic fatty amines and their derivatives e.g. octadecylamine acetate and quaternary ammonium halides, sulphonic acids e.g. dodecyl benzene sulphonic acid, ethylene oxide adducts of octyl or nonyl phenols e.g. octylphenoxypolyethoxyethanol, condensation products of aliphatic alcohols and ethylene oxide, monoesters of alcohols and fatty acids e.g. sodium lauryl sulphate glyceryl stearate, sorbitan monolaurate and polyoxyethylenemonostearate and polyvinyl alcohol. The surfactant component is generally employed in amounts of about 0.01% to about 55 by weight of the emulsion.

In the compositions of the present invention the component (C) is a quaternary ammonium silane Of the formula (iii).

Preferably at least one of the groups R3 is an alkyl group, preferably a methyl group and up to two of the groups R3 are alkoxy groups, preferably methoxy groups. The quaternary ammonium silanes are known materials and may be prepared in various ways, for example as disclosed In G.B. Patent Specifications 1 117 592 and 2 107 715. We prefer to prepare them from the corresponding tertiary amine and chlorosilane, trialkyl chlorosilanes are preferred over those containing readily hydrolysable groups, for example alkoxy and alkoxyalkoxy groups, thus avoiding production of disiloxanes and trisiloxanes during conversion of the silane to the quaternary ammonium salts.The group R4 may be for example -CCH2)3-, -CH2)4 , 2 2 3 -, -CH2CH2CHCH3CH2- or -CCH2)6- and the groups R5 may be chosen for example from methyl, ethyl, propyl, decyl, dodecyl, tetradecyl and octadecyl.

Preferably one only of the groups R5 has a longer aliphatic chain. We prefer that two of the groups R5 are methyl groups and one of them has an aliphatic chain having on average about 12 to 14 carbon atoms. The nature of the anion X influences the solubility of the sllane, whilst many organic and inorganic anions may be employed depending on the surfactant used in the emulsion, for example acetate, bromide and iodide, we prefer to employ the chloride ion.Examples of suitable quaternary ammonium silanes include those of the formulae (CK30)2CH3Si(CH2) 3N+(CH3)2(C13H27)C1 , (CH3O)2CH3Si(CH2)3N+CH3(C12H25)2Cl-, (CH3)3Si(CH2)3N IJL (CH3)2(C13H27)Cl, (CH3OCH2CH2O)(CH3O)2.Si(CH2)3N+(CH3)2(C18H37)Cl-, (CH3SiO)3Si(CH2)3N+(CH3)2(C13H27)Cl-, (CH3)2CH3CH2CH2Si(CH2)CH.CH3CH2N (CH3)2(C12R25)C1 .

The compositions of this invention comprise water having components (A), (B) and (C) dispersed therein. The cationic compounds (A) are generally soluble in water to at least some extei-jt and may thus exist in the compositions of this invention dissolved or dispersed in the aqueous phase. The organosiloxane (B) is substantially insoluble in water and is preferably provided in an oil-in-water emulsion. Thus, the term 'dispersion' as employed herein is intended to include solutions as well as emulsions or other forms of dispersion wherein the dIsperse phase is insoluble in the aqueous phase. Silane component (C) is water soluble and may be readily incorporated into the compositions of the invention by a simple mixing procedure. The compositions of the invention may be prepared by mixing (A) with organosiloxane (B) and thereafter emulsifying the resulting mixture in water followed by the addition of silane (C). More conveniently, however, (A), (B) and (C) are separately dispersed in water and the resulting dispersions mixed together. Alternatively, (A) may be added to and dispersed in an aqueous emulsion of (B), which may already contain (C) or to which (C) is added later. Depending on the solubility characteristics of (A) emulsifying agents may be employed to facilitate dispersion in the aqueous phase or to stabilise the dispersion.

The total concentration cf (A), (B) and (C) combined in the aqueous compositions of this invention is not critical and depends on practical and commercial considerations. For example the compositions should be sufficiently fluid as to be readily dispersible during the laundering operation. Also, they should preferably be not so dilute as to involve the cost of storing or transporting large volumes of water. Having regard to such considerations the preferred aqueous compositions are those wherein (A), (B) and (C) are present in a total amount of from about 5 to 35 by weight based on the total weight of the composition.

Depending on the desired effect the relative proportions of (A) and (B) may be varied within wide limits, for example from 1 to 50 parts by weight of the cationic compound (A) per part by weight of (B). For the optimum balance of properties and economy it is preferred to employ from about 2 to 20 parts by weight of (A) per part of (B). Up to 2% by weight of polydiorganosiloxane (B) may be used in the compositions of the invention, preferably no more than 1% of the polydiorganosi- loxaiie is used if its viscosity is in the preferred ranges mentioned above.The amount of (C) used in the compositions of the invention may vary from 0.2 to 1 part by weight per part of component (A). By incorporating Component (C) in those ratios the amount of Component (A) can be reduced without negatively affecting the properties which the compositions of the invention bestow on the treated material. In many instances superior characteristics are imparted by treatment with compositions of the invention compared to treatment with prior art compositions.

As a general rule it was found that the amount of Component (A) may be reduced by up to two thirds of its original amount and may be replaced by an amount of Component (C) up to half of the amount removed. Increasing the amount of Component (C) above this level is allowed but does not tend to improve the performlance of the textile treating composition. Preferably about 507O by weight of Component (A) is removed and replaced by half that amount of Component (C), resulting in a total reduction of quaternary compound by 25%. For example a textile treating composition which is sold with about 6% by weight of organic quaternary compounds will give at least equivalent performance when 3% of the organic quaternary compound is used and 1.5% quaternary silane (C) is added.A more concentrated composition having 18% organic quaternary compounds by weight may thus be replaced with 9% organic compound and 4.5% quaternary silane. In order to secure the desired blend of properties we prefer to employ Components (B) and (C) in proportions such thst ratio by weight of polydiorganosiloxane:silane is less than about 5:1, more preferably lies in the range 0.C5:1 to 2.5:1.

If the ratio lies outside this range the combination of properties achieved is inferior.

The aqueous compositions may contain in addition to (A), (B), (C) and water other, optional, ingredients for example perfumes, viscosity control agents, optical brighteners, colorants, opacifying agents, soil release agents, biocides and fabric treating agents such as the fatty acid esters of mcno- hydric and polyhydric alcohols. Such additional ingredients may be added to the preformed aqueous composition comprising (A), (B) and (C) or may be incorporated in admixture with (A), (B) and (C).

The compositions of this invention can be employed as fabric conditioners in domestic and commercial laundry operations. They are particularly adapted for use by addition at the rinsing stage of the washing cycle. In use the compositions of this invention are added to the rinse water in sufficient quantity to provide the desired effect. Generally the compositions will be added to provide from 5 to 500 parts by weight of (A), (B) and (C) combined per million parts of rinse water.The invention provides in another of its aspects a method of treating textile fabrics by applying to them in an n aqueous bath a composition comprising water having dispersed therein (A) an organic cationic compound which is substantive to water rinse on textile fibres, (B) a polydicrganosiloxane having units of the general formulae (i) R2R.SiO, and (ii) RaSiO4 a in which R is 2 selected from the group consisting of alkyl and aryl groups having up to 8 carbons atoms, R2 is selected from R groups and hydroxyl and a is an integer with a value of from 0 to 2, and (C) from 0.2 to 1 part by weight per part of component (A) of a quaternary ammonium silane of the general formula (iii) R33SiR4N+(R5)3X- in which each R is selected from the group consisting of alkyl groups having up to 5 carbon atoms in their chain, a hydroxyl group, alkoxy groups, alkoxyalkoxy groups 4 having less than 12 carbon atoms and a trimethylsiloxy group, R represents a divalent aliphatic hydrocarbon group having from 2 to 20 carbon atoms in its chain linking the silicon and nitrogen atoms and composed of carbon, hydrogen, optionally oxygen in the form of hydroxyl and optionally oxygen in the form of ether linkages, each R5 represents a monovalent hydrocarbon group, 1 or 2 groups R5 having an aliphatic chain composed of on average from 8 to 18 carbon atoms and 1 or 2 groups R5 having an aliphatic chain composed of not more than 5 carbon atoms and X represents a monovalent anion.

Also included in the present invention are fabrics for example cotton, polyester cotton or wool, treated with the compositions of this invention. They have a soft pleasant feel and generally exhibit a firmer 'body' and improved rewettability when compared with fabrics treated with the cationic compounds (A) alone or in combination with polydimethylsiloxanes.

There now follows a number of examples which illustrate the invention. All parts and percentages are expressed by weight unless otherwise specified.

Example 1 Preparation of Quaternary Ammonium Silane 1 mole of dimethoxymethylchloropropyl silane was reacted with 1.05 mole of (CH3)2N-R under a nitrogen blanket at 110 C.

The reaction was monitored by Bohr titration. For R=C12 14 after 36 hours 89% conversion was obtained giving a first quaternary ammonium silane; for R=8 a 96% conversion was obtained after 24 hours giving a second quaternary ammonium silane and for R=18 76X conversion was reached after 96 hours of reaction giving a third quaternary ammonium silane.

Preparation of Softener Compositions 0.2 part cf a non-ionic surfactant Makon 10 and 0.1 part of NaCl were added to water and the mixture heated to 6CeC. The quaternary compounds and, if used, other organic ingredients such as the handle modifier were heated to 600C and added slowly to the water with stirring. Stirring continued for 30 minutes during the cooling of the composition. Water was used in amounts up to 100 parts. iEen an emulsion was used this was added to the water together with the non-ionic surfactant and the salt.

Compositions which exemplified the invention and comparative compositions were prepared as shown in Table I.

TABLE I Parts of Components Composition A B C 1 3 (a) 1 (b) 1 (g) 2 3 (a) 1 (c) 1 (g) 3 3 (a) 1 (d) 1 (g) 4 3 (a) 0.3(e) 1 (g) 5 3 (a) 1 (e) 1 (g) 6 3 (a) 1.3(e) 1 (g) -7 3 (a) 1 (e) 1 (h) 8 3 (a) 1 (e) 1 (i) 9 3 (a) 0.7(f) 1.5(g) Comparative Compositions C 1 6 (a) --- - -- C 2 3 (a) --- --- C 3 3 (a) 0.3(e) C 4 3 (a) 0.7(e) C 5 3 (a) 1 (e) -- C 6 5.3(a) 0.7(f) --- C 7 3 (a) --- 0.3(g) C 8 3 (a) --- 0.7(g) C 9 3 (a) --- 1 (g) C10 3 (a) --- 1.5(g) (a) is di(hydrogenated)tallowdimethyl ammonium chloride (b) is polydimethylsiloxane 50 mm2/s provided in an emulsion (c) is polydimethylsiloxane 1000 mm2/s provided as for (b) (d) is polydimethylsiloxane 12500 mm2/s provided as for (b) (e) is polydimethylsiloxane 100000 mm2/s provided as for (b) (f) is 1 part of polydimethylsiloxane gum diluted in 8 parts of cyclic polydimethylsiloxane provided in an emulsion (g) is the first quaternary ammonium silane (h) is the second quaternary ammonium silane (i) is the third quaternary ammonium silane.

Testing of the Compositions Pieces of cotton (20 x 20cm) were washed 3 times in an

automatic wasting macnine using Bersl. Atter the there wasn the pieces were air dried overnight at room temperature. A treatment bath was prepared using 2 litres of cold water and 50g of the composition to be tested, giving a solids content of about 1.5 te 3g of the test compositions per 2 litres of the treatment bath. Each fabric piece was immersed in the bath for 15 minutes while the bath was agitated at regular intervals.

When the pieces were removed excess water was drained and the pieces were placed oil paper towelling prior to hanging on lines for alr drying. The pieces were assessed for softness, handle and body by a panel of experienced people. Test results were as follows: Composition 8 = 6 > 7 Composition 4 > 3 ) 2 ? 1 Composition 9 > C10 > C6 > ) C1.

= means similar performance > means better performance Rewettability was tested by allowing a calibrated drop cf water to fall onto the surface of the pieces from a height of lem.

ihe time to absorb the water was recorded in seconds. These test results are as given in Table II.

TABLE II Composition Rewettability in Seconds (on Cotton) C2 19 C3 3 C4 5 C5 2 C7 7 C8 5 C 9 3 5 2 6 1 The above results show that the tested compositions according to the invention give an improved performance compared with those of the prior art.

Claims (9)

1. Aqueous composition for the treatment of textiles which comprises water having dispersed therein (A) an organic cationic compound which is substantive to water rinse on textile fibres, (B) a polydiorganosiloxane having units of the general formulae (i) R2R2SiO, and (ii) RaSIO4a in which R is selected from the 2 group consisting of alkyl and aryl groups having up to 8 carbon atoms, R2 is selected from R groups and hydroxyl and a is an integer with a value of from 0 to 2 and (C) from 0.2 to 1 part by weight per part of component (A) of a quaternary ammonium silane of the general formula (iii) R3 SiR4N+(R5) X in which 3 3 each R3 is selected from the group consisting of alkyl groups having up to 5 carbon atoms in their chain, a hydroxyl group, alkoxy groups, alkoxyalkoxy groups having less than 12 carbon atoms and a trinethylsiloxy group, R4 represents a divalent aliphatic hydrocarbon group having from 2 to 10 carbon atoms in its chain linking the silicon and nitrogen atoms and composed of carbon, hydrogen, optionally oxygen in the form of hydroxyl and optionally oxygen in the form of ether linkages, each represents a monovalent hydrocarbon group, 1 or 2 groups R5 having an aliphatic chain composed of on average from 8 to 18 carbon atoms and 1 or 2 groups R5 having an aliphatic chain composed of not more than 5 carbon atoms and X represents a monovalent anion.

2. A composition according to Claim 1 in which Component (B) is a linear polydiorganosiloxane provided as an oil-in-water emulsion.

3. A composition according to Claim 1 or Claim 2 in which at least one R3 group is an alkyl group, the other R3 groups being alkoxy groups.

4. A composition according to any one of the preceding claims in which no more than one R5 group has a longer aliphatic chain.

5. A composition according to any one of the preceding claims in which Components (A), (B) and (C) are present in a total amount of from 5 to 35% by weight based on the total weight of the composition.

6. A composition according to any one of the preceding claims in which from 2 to 20 parts by weight of (A) are present per part by weight of (B).

7. A composition according to Claim 1 with reference to any of the Example Compositions 1 to 9.

8. A method of treating textile fabrics by applying to them in an aqueous bath a composition according to any one of the preceding claims.

9. Textile fabrics when treated with a composition according to any one of Claims 1 to 6.