WO2002050366A1

WO2002050366A1 - Siloxane dry cleaning composition and process

Info

Publication number: WO2002050366A1
Application number: PCT/US2001/026665
Authority: WO
Inventors: Robert J. Perry; Donna Ann Riccio; Larry D. Ryan
Original assignee: General Electric Company
Priority date: 2000-12-20
Filing date: 2001-08-24
Publication date: 2002-06-27
Also published as: EP1346100A1; AU2001285299A1; JP2004523608A; US20020004953A1

Abstract

A dry cleaning composition comprising a volatile siloxane and a mixture of different classes of organic surfactants and, optionally water, and a method for dry cleaning comprising contacting an article with a composition comprising a volatile siloxane and a mixture of different classes of organic surfactants.

Description

SILOXANE DRY CLEANING COMPOSITION AND PROCESS

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims rights of priority from U.S. Provisional Patent Application Serial No. 60/187,204, filed March 3, 2000.

TECHNICAL FIELD

The present invention is directed to a dry cleaning composition, more specifically, to a siloxane fluid based composition, for use in dry cleaning and to a dry cleaning process using the composition.

BACKGROUND

Current dry cleaning technology uses perchloroethylene ("PERC") or petroleum-based materials as the cleaning solvent. PERC suffers from toxicity and odor issues. The petroleum-based products are not as effective as PERC in cleaning garments.

Cyclic siloxanes have been reported as spot cleaning solutions, see US 4,685,930, and as dry cleaning fluids in dry cleaning machines, see US 5,942,007. Other patents disclose the use of silicone soaps in petroleum solvents, see JP 09299687, and the use of silicone surfactants in super critical carbon dioxide solutions has been reported, see, for example, US 5,676,705 and Chem. Mark. Rep., 15 Dec 1997, 252(24), p. 15. Non-volatile silicone oils have also been used as the cleaning solvent requiring removal by a second washing with perfluoroalkane to remove the silicone oil, see JP 06327888.

Numerous other patents have issued in which siloxanes or organomodified silicones have been present as addenda in PERC or petroleum based dry cleaning solvents, see, for example, WO 9401510; US 4911853; US 4005231; US 4065258.

There is. a continued interest in providing an additive or additives to enhance the cleaning ability of silicone based dry cleaning solvents.

SUMMARY OF THE INVENTION

In a first aspect, the present invention is directed to a dry cleaning composition, comprising a volatile siloxane and two or more surfactants.

In a second aspect, the present invention is directed to a method for dry cleaning an article, comprising contacting the article with a composition comprising a volatile siloxane and two or more surfactants.

In a third aspect, the present invention is directed to a concentrate composition, comprising two or more surfactants.

The composition and process of the present invention exhibit improved performance, such as for example, removal of water soluble stains from the article, for example a garment, being cleaned, improved feel and hand, and improved refinishing of the article. The present invention also provides for the removal of oil soluble stains such as motor oil and grease.

DETAILED DESCRIPTION OF THE INVENTION

In a preferred embodiment, the composition comprises, based on 100 parts by weight ("pbw") of the composition, from greater than 90 pbw to 99.99 pbw, more preferably from 92 pbw to 99.9 pbw and even more preferably from 95 pbw to 99.5 pbw of the volatile siloxane and from 0.001 pbw to less than 10 pbw, more preferably from 0.01 pbw to 8 pbw and even more preferably from 0.1 pbw to 5 pbw of the surfactants. The composition optionally further comprises water, preferably from 0.01 pbw to 15 pbw, more preferably from 01 pbw to less than 12 pbw and even more preferably from 0.2 pbw to 10 pbw of water. The volatile siloxane utilized in the present invention may be a linear, branched or cyclic siloxane.

In a preferred embodiment, the water may be added as "free" water or may be delivered by an emulsion containing other components such as siloxanes, hydrocarbons, surfactants, or other suitable additives. If the water is delivered by an emulsion, the emulsion may be prepared by such methods as homogenization of the components or mechanical stirring of the mixture.

In a preferred embodiment, the surfactant comprises two or more organic surfactants selected from the classes of nonionic, cationic, anionic and amphoteric surfactants. In one preferred embodiment, two organic surfactants are mixed together for use in the composition. In another preferred embodiment, three organic surfactants are mixed together for use in the composition. In another preferred embodiment, four organic surfactants are mixed together for use in the composition. In another preferred embodiment, five organic surfactants are mixed together for use in the composition. In another preferred embodiment, more than five organic surfactants are mixed together for use in the composition.

In another preferred embodiment of the present invention, a concentrate composition comprises two or more surfactants, preferably two or more organic surfactants selected from the classes of nonionic, cationic, anionic and amphoteric surfactants. The composition comprises, based on 100 pbw of the composition, from 0.1 to 99.9 pbw of one surfactant and from 0.1 to 99.9 pbw of a second surfactant. Optionally, the concentrate composition may further comprise from 0.1 to 99.8 pbw of one or more additional organic surfactants. The concentrate composition may optionally further comprise a siloxane fluid. The concentrate composition may be added to a cleaning fluid, for example a dry cleaning solvent, for use in cleaning processes.

Compounds suitable as the linear or branched, volatile siloxane ' solvent of the present invention are those containing a polysiloxane structure that includes from 2 to 20 silicon atoms. Preferably, the linear or branched, volatile siloxanes are relatively volatile materials, having, for example, a boiling of below about 300°C point at a pressure of 760 millimeters of mercury ("mm Hg").

In a preferred embodiment, the linear or branched, volatile siloxane comprises one or more compounds of the structural formula (I):

Ma+y+^DxTyQz (I)

wherein:

and Q is Si0₄/2

R¹, R², R³ and R⁴ are each independently a monovalent hydrocarbon radical; and

x and y are each integers, wherein 0 < x < 10 and 0 < y < 10 and 0 < z < 10.

Suitable monovalent hydrocarbon groups include acyclic hydrocarbon radicals, monovalent alicyclic hydrocarbon radicals, monovalent and aromatic or fluoro containing hydrocarbon radicals. Preferred monovalent hydrocarbon radicals are monovalent alkyl radicals, monovalent aryl radicals and monovalent aralkyl radicals. In a highly preferred embodiment, the monovalent hydrocarbon radical is a monovalent (O-C_ό)alkyl radical, most preferably, methyl.

As used herein, the term "(Cι-C6)alkyl" means a linear or branched alkyl group containing from 1 to 6 carbons per group, such as, for example, methyl, ethyl, propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl, pentyl, hexyl, preferably methyl.

As used herein, the term "aryl" means a monovalent unsaturated hydrocarbon ring system containing one or more aromatic or fluoro containing rings per group, which may optionally be substituted on the one or more aromatic or fluoro containing rings, preferably with one or more (O- Cό)alkyl groups and which, in the case of two or more rings, may be fused rings, including, for example, phenyl, 2,4,6-trimethylphenyl, 2- isopropylmethylphenyl, 1-pentalenyl, naphthyl, anthryl, preferably phenyl.

As used herein, the term "aralkyl" means an aryl derivative of an alkyl group, preferably a (C2-C₆)alkyl group, wherein the alkyl portion of the aryl derivative may, optionally, be interrupted by an oxygen atom, such as, for example, phenylethyl, phenylpropyl, 2-(l-naphthyl)ethyl, preferably phenylpropyl, phenyoxypropyl, biphenyloxypropyl.

In a preferred embodiment, the linear or branched, volatile siloxane comprises one or more of, hexamethyldisiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, dodecamethylpentasiloxane, tetradecamethylhexasiloxane or hexadecamethylheptasiloxane or methyltris(trimethylsiloxy)silane. In a more highly preferred embodiment, the linear or branched, volatile siloxane of the present invention comprises octamethyltrisiloxane, decamethyltetrasiloxane, or dodecamethylpentasiloxane or methyltris(trimethylsiloxy)silane. In a highly preferred embodiment, the siloxane component of the composition of the present invention consists essentially of decamethyltetrasiloxane.

Suitable linear or branched volatile siloxanes are made by known methods, such as, for example, hydrolysis and condensation of one or more of tetrachlorosilane, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, or by isolation of the desired fraction of an equilibrate mixture of hexamethyldisiloxane and octamethylcyclotetrasiloxane or the like and are commercially available.

Compounds suitable as the cyclic siloxane component of the present invention are those containing a polysiloxane ring structure that includes from 2 to 20 silicon atoms in the ring. Preferably, the linear, volatile siloxanes and cyclic siloxanes are relatively volatile materials, having, for example, a boiling point of below about 300°C at a pressure of 760 millimeters of mercury ("mm Hg").

In a preferred embodiment, the cyclic siloxane component comprises one or more compounds of the structural formula (II):

R5 R7

(Si O)_a (Si O)b

R6 R8 (π)

wherein:

R⁵, R⁶, R⁷ and R⁸ are each independently a monovalent hydrocarbon group, preferably a (Cι-Cό)alkyl, more preferably, methyl; and a and b are each integers wherein 0 < a < 10 and 0 < b < 10, provided that 3 < (a + b) < 10. In a preferred embodiment, the cyclic siloxane comprises one or more of, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, tetradecamethylcycloheptasiloxane. In a more highly preferred embodiment, the cyclic siloxane of the present invention comprises octamethylcyclotetrasiloxane or decamethylcyclopentasiloxane. In a highly preferred embodiment, the cyclic siloxane component of the composition of the present invention consists essentially of decamethylcyclopentasiloxane.

Suitable cyclic siloxanes are made by known methods, such as, for example, hydrolysis and condensation of dimethyldichlorosilane and are cornmercially available.

The organic surfactants of the present invention comprise two or more surfactants selected from nonionic, cationic, anionic and amphoteric surfactants. The surfactants may comprise two or more surfactants selected from the same or different classes.

Compounds suitable for use as the nonionic surfactant of the present invention are those that carry no discrete charge when dissolved in aqueous media. Nonionic surfactants are generally known in the art and include, for example, alkanol amides (such as, for example, coco, lauric, oleic and stearic monoethanolamides, diethanolamides and monoisopropanolamides), amine oxides (such as, for example, polyoxyethylene ethanolamides and polyoxyethylene propanolamides), polyalkylene oxide block copolymers (such as, for example, poly(oxyethylene-co-oxypropylene)), ethoxylated alcohols, (such as, for example, isostearyl polyoxyethylene alcohol, lauryl, cetyl, stearyl, oleyl, tridecyl, trimethylnonyl, isodecyl, tridecyl), ethoxylated alkylphenols (such as, for example, nonylphenol ), ethoxylated amines and ethoxylated amides, ethoxylated fatty acids, ethoxylated fatty esters and ethoxylated fatty oils (such as, for example, mono- and diesters of acids such as lauric, isostearic, pelargonic, oleic, coco, stearic, and ricinoleic, and oils such as castor oil and tall oil), fatty esters, fluorocarbon containing materials, glycerol esters (such as, for example, glycerol monostearate, glycerol monolaurate, glycerol dilaurate, glycerol monoricinoleate, and glycerol oleate), glycol esters (such as, for example, propylene glycol monostearate, ethylene glycol monostearate, ethylene glycol distearate, diethylene glycol monolaurate, diethylene glycol monolaurate, diethylene glycol monooleate, and diethylene glycol stearate), lanolin-based surfactants, monoglycerides, phosphate esters, polysaccharide ethers, propoxylated fatty acids, propoxylated alcohols, and propoxylated alkylphenols, protein-based organic surfactants, sorbitan-based surfactants (such as, for example, sorbitan oleate, sorbitan monolaurate, and sorbitan palmitate), sucrose esters and glucose esters, and thio- and mercapto-based surfactants.

In a preferred embodiment, one component of the present invention comprises one or more nonionic surfactants according to one or more of the structural formulas III and IV:

R^Q-0-(CH₂-CH₂-0)n-R¹⁰ (III)

R⁹-0-(CH2-C(CH3)H-0)n-R¹⁰ (IV)

wherein:

R⁹ is a monovalent hydrocarbon group of from 1 to 30 carbons that may be linear, cyclic, branched, unsaturated, aromatic or fluoro containing; R¹⁰ is hydrogen or a monovalent hydrocarbon group of 1 to 30 carbons that may be linear, cyclic, branched, unsaturated, aromatic or fluoro containing; and n is from about 1 to about 100, more preferably from about 1 to about 40. In a highly preferred embodiment, R⁹ contains from 2 to about 24 carbons, even more preferably from 8 to 24 carbons, R¹⁰ is H and n is from about 2 to about 20.

In another preferred embodiment, one component of the present invention comprises one or more nonionic surfactants that may be a sugar- based surfactant according to one or more of the structural formulas V and VI:

wherein:

each R¹⁷, R" R19, R20_/ RΏ R_2 R23_/ R24 _and R25 {_S independently H or a monovalent hydrocarbon group of 1 to 30 carbons that may be linear, cyclic, branched, an oxygenated alkane or other chalcogen containing group. These surfactants may also be the open-chain analogs. In a preferred embodiment each R¹⁷, R¹⁸, R^1Q, R20, R2i. R R∞ R24 _and R25 {_S independently H or a hydroxy-terminated polyoxyethylene of 1 to 10 repeat units, a monovalent hydrocarbon group of 1 to 4 carbons or a carboxyalkyl group of from 2 to 9 carbons. In another preferred embodiment, R¹⁷, R²⁰ and R²¹ are monovalent hydrocarbon radicals of 8 of 20 carbons and R²⁵ is -CH₂-OR' with R' a hydrocarbon group of from 1 to 4 carbons.

In another preferred embodiment, one component of the present invention comprises one or more nonionic surfactants that may be an amine- based or phosphate ester-based surfactant according to one or more of the structural formulas VII and VIII:

_R14 O

\ •' 16

N-C-R¹⁶

R 15'

(VII)

wherein:

each R¹¹, R¹², R¹³, R¹⁴, R¹⁵, and R¹⁶ is independently H or a monovalent hydrocarbon group of 1 to 30 carbons that may be linear, cyclic, branched, unsaturated, aromatic, fluoro containing, an oxygenated alkane or other chalcogen containing group. In a preferred embodiment, R¹¹, R¹², R¹⁴ and R¹⁵ are H or monovalent hydrocarbon radicals of 1 to 4 carbons and R¹³ and R¹⁶ are monovalent hydrocarbon radicals of 6 to 24 carbons. In another preferred embodiment, R¹¹, R¹², R¹⁴ and R¹⁵ are monovalent hydrocarbon radicals of 6 to 24 carbons and R¹³ and R¹⁶ are H or monovalent hydrocarbon radicals of 1 to 4 carbons.

Compounds suitable for use as the anionic surfactant of the present invention are those having polar, solubilizing groups such as carboxylate, sulfonate, sulfate and phosphate. Anionic surfactants are generally known in the art and include, for example, alkyl aryl sulfonates (such as, for example, alkylbenzenesulf onates), alkyl aryl sulfonic acids (such as, for example, sodium and ammonium salts of toluene-, xylene- and isopropylbenzenesulfonic acids), sulfonated amines and sulfonated amides (such as, for example, amidosulfonates), carboxylated alcohols and carboxylated alkylphenol ethoxylates, diphenyl sulfonates, fatty esters, isethionates, lignin-based surfactants, olefin sulfonates (such as, for example, RCH=CHS0₃Na, where R is Cιo-Cι₆), phosphorous-based surfactants, protein based surfactants, sarcosine-based surfactants (such as, for example, N- acylsarcosinates such as sodium N-lauroylsarcosinate), sulfates and sulfonates of oils and/ or fatty acids, sulfates and sulfonates of ethoxylated alkylphenols, sulfates of alcohols, sulfates of ethoxylated alcohols, sulfates of fatty esters, sulfates of aromatic or fluoro containing compounds, sulfosuccinnamaf.es, sulfosuccinates (such as, for example, diamyl-, dioctyl- and diisobutylsulfosuccinates), taurates, and sulfonic acids.

In a preferred embodiment, one component of the present invention comprises one or more anionic surfactants that may be a sulfosuccinate, sulfate, sulfonate, carboxylate, or phosphorous containing surfactant according to one or more of the structural formulas IX to XIII:

(R²⁸-OS0₃-)_q X⁺ (X)

(R²⁸-S0₃-)_q X⁺ (XI) (R²⁹-C0₂-)_qX⁺ (XII)

(R³°-OP0₃-)_q X⁺ (XIII)

wherein:^'

each R²⁶, R²⁷, R²⁸, R²⁹ and R³⁰ is independently a monovalent hydrocarbon group of 1 to 30 carbons that may be linear, cyclic, branched, unsaturated, aromatic, fluoro containing, an oxygenated alkane or other chalcogen containing radical, and X is H or an alkali metal, alkaline earth element or a chalcogen containing counterion or other suitable cation that does not unduly interfere with the functioning of the molecule as a surfactant where the subscript q is the valence or oxidation state of the cation X. In a preferred embodiment, R²⁶ and R²⁷ are each independently a linear, cyclic, or branched monovalent hydrocarbon group of 4 to 20 carbons, more preferably a linear, cyclic, or branched monovalent hydrocarbon group of 6 to 13 carbons; R²⁸ is a monovalent hydrocarbon group of 4 to 20 carbons, more preferably from 8 to 16 carbons; R²⁹ is monovalent hydrocarbon group of 8 to 26 carbons, more preferably from 10 to 20 carbons; and R³⁰ is monovalent hydrocarbon group of 8 to 30 carbons.

Compounds suitable for use as the cationic surfactant of the present invention are those having a positive charge when dissolved in aqueous media, which resides on an amino or quaternary nitrogen. Cationic surfactants are generally known in the art and include, for example, amine acetates, amines (such as, for example, oxygen-free amines such as monoalkylamines, dialkylamines and N-alkyltrimethylene diamines, and oxygen-containing amines such as amine oxides, ethoxylated alkylamines, 1- (2-hydroxyethyl)-2-imidazolines, and alkoxylates of ethylenediamine), and quaternary ammonium salts (such as, for example, dialkyldimethylammonium salts, alkylbenzyldimethylammonium chlorides, alkyltrimethylammonium salts and alkylpyridium halides), and quaternary ammonium esters (such as, for example, diethyl ester dimethyl ammonium chloride).

In a preferred embodiment, one component of the present invention comprises one or more cationic surfactants that may be a quaternary amine- based surfactant according to the structural formula XIV

(R31R3ZR33R3 JNJ+)_pJ- (XIV)

wherein:

each R³¹, R³², R³³, and R³⁴ is independently H or a monovalent hydrocarbon group of 1 to 30 carbons that may be linear, cyclic, branched, unsaturated, aromatic, fluoro containing, an oxygenated alkane or other chalcogen containing group, and J is a suitable anion having an oxidation state or valence p that does not unduly interfere with the functioning of the molecule as a surfactant. In a preferred embodiment, R³¹ and R³² are each independently a monovalent hydrocarbon radical of 1 to 4 carbons and R³³ and R³⁴ are each independently a monovalent hydrocarbon radical of 8 to 24 carbons.

Compounds suitable for use as the amphoteric surfactant of the present invention are those containing both an acidic and basic hydrophilic group. Amphoteric surfactants are compatible with anionic and cationic surfactants. Amphoteric surfactants are generally known in the art and include, for example, betaine derivatives such as alkylbetaines and amidopropylbetaines, block copolymers, imidazolines and lecithins. In a preferred embodiment, one component of the present invention comprises one or more amphoteric surfactants according to the structural formula XV:

wherein:

each R³⁵, R³⁶ and R³⁷ is independently H or a monovalent hydrocarbon group of 1 to 30 carbons that may be linear, cyclic, branched, unsaturated, aromatic, fluoro containing, an oxygenated alkane or other chalcogen containing group, G is a divalent spacer group, Y is a carboxylate, sulfonate, sulfate, phosphonate or other similar group. In a preferred embodiment, R³⁵ is a monovalent hydrocarbon group of 1 to 4 carbons, more preferably methyl, and R³⁶ and R³⁷ are each independently monovalent hydrocarbon group of 6 to 24 carbons.

Surfactants are known in the art and are commercially available under many trade names from many sources, such as for example, Akzo Chemical

Co., Calgene Chemical Inc., Emkay Chemical Co., Hercules, Inc., ICI Americas Inc., Lonza, Inc., Rhone Poulenc, Inc., Union Carbide Corp. and Witco Corp.

Generally the compositions of the present invention comprise two or more surfactants selected from the group consisting of anionic, nonionic, cationic and amphoteric surfactants. In one preferred embodiment, the composition of the present invention comprises two or more anionic surfactants, or two or more cationic surfactants, or two or more nonionic surfactants or two or more amphoteric surfactants, preferably two or more anionic surfactants or two or more nonionic surfactants. In another preferred embodiment, the composition of the present invention comprises a sulfosuccinate surfactant and a sulfonic acid surfactant, more preferably sulfosuccinate and dodecylbenzenesulfonic acid, or a sulfated anionic surfactant and a sulfosuccinate, or a sulfated anionic surfactant and a sulfonic acid surfactant, more preferably sulfosuccinate and dodecylbenzenesulfonic acid, or a nonionic polymeric surfactant and an ethoxylated alcohol.

In another preferred embodiment, the composition of the present invention comprises at least two surfactants selected from anionic, nonionic, cationic and amphoteric surfactants, provided that at least two of the surfactants are selected from two different members of the group of surfactants, such that there is at least one anionic surfactant and at least one cationic surfactant, or at least one anionic surfactant and at least one nonionic surfactant, or at least one nonionic surfactant and at least one cationic surfactant, or at least one anionic surfactant and at least one amphoteric surfactant, or at least one amphoteric surfactant and at least one cationic surfactant or at least one nonionic surfactant and at least one amphoteric surfactant. In a highly preferred embodiment, the composition of the present invention comprises a sulfoccinate and a quaternary ammonium salt, or a sulfated anionic surfactant and an ethoxylated alcohol, or a sulfonic acid, more preferably dodecylbenzenesulfonic acid, and a nonionic polymeric surfactant, or a sulfosuccinate and a nonionic polymeric surfactant, or a sulfonic acid, more preferably dodecylbenzenesulfonic acid, and an ethoxylated alcohol, or a sulfonic acid, more preferably dodecylbenzenesulfonic acid, and a quaternary ammonium salt, or a sulfated anionic surfactant and a quaternary ammonium salt, or a sulfated anionic surfactant and a nonionic polymeric surfactant, or a sulfated anionic surfactant and an ethoxylated alcohol, or a sulfated anionic surfactant and a quaternary ammonium salt, or an ethoxylated alcohol and a quaternary ammonium salt, or a sulfosuccinate, a sulfated anionic surfactant and two different ethoxylated alcohols, or a sulfosuccinate, a sulfated anionic surfactant and a quaternary ammonium salt.

In another preferred embodiment, the composition of the present invention comprises at least three surfactants selected from the group consisting of anionic, nonionic, cationic and amphoteric surfactants.

Preferably these surfactants may be chosen wherein each of the three surfactants are selected from different surfactants in terms of anionic, nonionic, cationic or amphoteric, for example is at least one anionic surfactant, at least one cationic surfactant and at least one nonionic surfactant, or at least one anionic surfactant, at least one cationic surfactant and at least one amphoteric surfactant, or at least one cationic surfactant, at least one nonionic surfactant and at least one amphoteric surfactant. In a highly preferred embodiment, the composition of the present invention comprises a sulfosuccinate, a sulfated anionic surfactant, two different ethoxylated alcohols, and a quaternary ammonium salt, or a sulfated anionic surfactant, an ethoxylated alcohol and a quaternary ammonium salt.

In another preferred embodiment, the composition of the present invention comprises at least four surfactants selected from the group of anionic, nonionic, cationic and amphoteric surfactants, provided that at least one surfactant is selected from each member of the group of surfactants, such that there is at least one anionic surfactant, at least one cationic surfactant, at least one nonionic surfactant and at least one amphoteric surfactant.

The dry cleaning composition of the present invention is made by adding to the siloxane fluid two or more surfactants and mixing to form a homogeneous solution. The surfactants may be mixed together before addition to the siloxane, or they may added to the siloxane individually. In a preferred embodiment, the dry cleaning composition of the present invention further comprises a minor amount, preferably, less than 50 pbw per 100 pbw of the composition, more preferably, less than 10 pbw per

100 pbw of the composition, of one or more non-siloxane fluids. Suitable non- siloxane fluids include aqueous fluids, such as, for example, water, and organic fluids, for example, hydrocarbon fluids and halogenated hydrocarbon fluids.

According to the process of the present invention, an article, such as for example, a textile or leather article, typically, a garment, is dry cleaned by contacting the article with the composition of the present invention. In a preferred embodiment, the articles to be cleaned include textiles made from natural fibers, such as for example, cotton, wool, linen and hemp, from synthetic fibers, such as, for example, polyester fibers, polyamide fibers, polypropylene fibers and elastomeric fibers, from blends of natural and synthetic fibers, from natural or synthetic leather or natural or synthetic fur.

The article and dry cleaning composition are then separated, by, for example, one or more of draining and centrifugation. In a preferred embodiment, separation of the article and dry cleaning composition is followed by the application of heat, preferably, heating to a temperature of from 15°C to 120°C, preferably from 20°C to 100°C, or reduced pressure, preferably, a pressure of from 1 mm Hg to 750 mm Hg, or by application of both heat and reduced pressure, to the article.

The surfactant components of the dry cleaning composition a ; re typically depleted through use in the cleaning cycle. Some of the surfactants remain on the articles being cleaned. To promote efficient cleaning of articles, the dry cleaning solvent is periodically cleaned or refreshed, preferably distilled, to remove the dirt that has been removed from the articles being cleaned. Once the solvent has been cleaned, additional surfactants are typically added to the cleaned solvent to replenish the amount of surfactants in the solvent. This process is repeated periodically, depending on the number of uses and the amount of soil on articles being cleaned, so that the solvent will effectively clean and remove soil from articles, and each time, additional surfactants are added to the solvent.

In another preferred embodiment, the concentrate composition of the present invention is added to the dry cleaning composition to replenish the surfactants that have been depleted.

The concentrate composition of the present invention can be made in any of the combinations of organic disclosed above, such as, for example, a concentrate composition comprising at least one anionic surfactant and at least one cationic surfactant, or at least two anionic surfactants. The concentrate composition may optionally further comprise a siloxane fluid. In a highly preferred embodiment, the concentrate composition of the present invention comprises at least one anionic surfactant and at least one nonionic surfactant, and optionally, a siloxane fluid. The concentrate composition may optionally further comprise additional components known in the art, such as, for example, brighteners, softeners, water, fragrances and the like.

The concentrate composition of the present invention is made by adding together two or more surfactants in desired amounts, and optionally, a siloxane fluid> and stirring to form a homogeneous solution. The concentrate may then be added to a siloxane fluid to form a dry cleaning fluid at any time, such as before the initial cleaning, or after the fluid has been used to replenish the amount of surfactant in the cleaning fluid. The surfactant level in the cleaning fluid is depleted through routine use and cleaning. Testing for water soluble stain removal was accomplished using fabric swatches supplied by the International Fabricare Institute ("IFI") (Silver Spring, MD) that contained a water soluble dye. The color change of a swatch of this material was measured by a Minolta CR-300^® Colorimeter using the Hunter Color Number difference calculations. The larger the change in Hunter Color Number (ΔE), the greater the dye removal and the more efficient the cleaning.

The following examples are to illustrate the invention and are not to be construed as limiting the claims.

EXAMPLES

Testing procedure: Circular swatches (from IFI) containing a water soluble dye were measured by the colorimeter, and the initial color values for L, a and b (as defined by the Hunter Color Numbers) were recorded.- The fabric swatches were then placed in vials containing the cleaning composition of the present invention, and the vial was shaken for 10 minutes at ambient temperature. The fabric swatch was removed and allowed to drip dry for 2 to 5 seconds, then placed on absorbent toweling and allowed to air dry for 16 to 24 hours. A second reading of each fabric swatch was taken and the color difference (ΔE) was determined using the following formula:

ΔE = [(L1-L2)² + (aι-a₂) ² = (bι-b₂) ²] ²

This color difference represents the relative amount of cleaning, with the higher ΔE indicative of better cleaning performance. Surfactants used in the Examples

Commercially available from Cytek Industries **Commercially available from Henkel Canada Ltd. A cleaning composition according to the present invention containing a cyclic siloxane (D5) and a mixture of two surfactants from different surfactant classes was made. Fabric swatches were cleaned using the above procedure, and the color difference was measured to determine the effectiveness of the cleaning composition. A solution of cyclic siloxane (D₅) without a surfactant was used as a control. Results are shown in Table 1 below.

Table 1 - Binary Mixtures of Surfactants in D5

As shown in Table 1, almost all the binary mixtures exhibited good cleaning when compared to the control. The synergistic relationship exhibited by some of the mixtures of different surfactant classes was highly unexpected and is denoted in the column labeled enhanced cleaning. Results were considered unexpected when a ΔE value greater the average of the two single surfactant ΔE values resulted from an experiment. Such unexpected results are noted with a mark in all the columns, infra, entitled "enhanced cleaning."

Table 2 shows the results of using a mixture of two different surfactants from different surfactant classes in a linear volatile siloxane. A solution of MD2M was used as a control.

Table 2 - Binary Mixtures of Surfactants in MD2M

Table 2 shows good cleaning behavior in linear siloxane solvent. Several binary compositions exhibited enhanced (unexpected results) cleaning characteristics.

A cleaning composition according to the present invention containing a cyclic siloxane (D5) and a mixture of three or more surfactants from different surfactant classes was made. Fabric swatches were cleaned using the above procedure, and the color difference was measured to determine the effectiveness of the cleaning composition. A solution of cyclic siloxane (D5) without a surfactant was used as a control. Table 3 - Mixtures of Three or More Surfactants

Table 3 shows that good cleaning can be obtained from mixtures of three organic surfactants with water optionally present.

Table 4. Higher Order Mixtures

Table 4 shows cleaning benefits derived from a multiple combination of organic surfactants. Concentrates of surfactants were also made as exemplified by the following 2 examples.

Concentrate 1 : 4 parts surfactant B, 2 parts, surfactant E, 2 parts surfactant K and 2 parts surfactant I were added together in an appropriate container and stirred to form a homogeneous solution.

Concentrate 2 : 2 parts surfactant E, 2 parts, surfactant A; and 2 parts surfactant R were added together in an appropriate container and stirred to form a homogeneous solution.

The present invention exhibits improved performance of dry cleaning agents for stain removal, particularly water soluble stains, through the addition of a mixture of different classes of surfactants, and optionally, water.

Claims

CLAIMS: Having described the invention that which is claimed is:

1. A dry cleaning composition, comprising a volatile cyclic, linear or branched siloxane, or mixture thereof, and two or more organic surfactants.

2. The composition of Claim 1, comprising from about 90 to about

99.99 parts by weight of the volatile siloxane and from about 0.001 to less than 10 parts by weight of the surfactants.

3. The composition of Claim 2, further comprising from about 0.01 to about 15 parts by weight of water.

4. The composition of Claim 1, wherein the surfactants are selected from the classes of nonionic, cationic, anionic and amphoteric surfactants.

5. The composition of Claim 1, further comprising a silicone surfactant or mixture of silicone surfactants.

6. The composition of Claim 1, comprising two or more nonionic surfactants.

7. The composition Claim 1, comprising two or more cationic surfactants.

8. The composition of Claim 1, comprising two or more anionic surfactants.

9. The composition of Claim 1 comprising two or more amphoteric surfatctants.

10. The composition of Claim 6, further comprising a silicone surfactant or mixture of silicone surfactants.

11. The composition of Claim 7, further comprising a silicone surfactant or mixture of silicone surfactants.

12. The composition of Claim 8, further comprising a silicone surfactant or mixture of silicone surfactants.

13. The composition of Claim 9, further comprising a silicone surfactant or mixture of silicone surfactants.

14. A dry cleaning composition, comprising a volatile cyclic, linear or branched siloxane, or mixture thereof, and three or more organic surfactants.

15. The composition of Claim 14, comprising from about 90 to about

16. The composition of Claim 15, further comprising from about 0.01 to about 15 parts by weight of water.

17. The composition of Claim 14, wherein the surf actants are selected from the classes of nonionic, cationic, anionic and amphoteric surfactants.

18. The composition of Claim 14, further comprising a silicone surfactant or mixture of silicone surfactants.

19. The composition of Claim 14, comprising two or more nonionic surfactants.

20. The composition Claim 14, comprising two or more cationic surfactants.

21. The composition of Claim 14, comprising two or more anionic surfactants.

22. The composition of Claim 14 comprising two or more amphoteric surfatctants.

23. The composition of Claim 19, further comprising a silicone surfactant or mixture of silicone surfactants.

24. The composition of Claim 20, further comprising a silicone surfactant or mixture of silicone surfactants.

25. The composition of Claim 21, further comprising a silicone surfactant or mixture of silicone surfactants.

26. The composition of Claim 22, further comprising a silicone surfactant or mixture of silicone surfactants.