EP1001008A1

EP1001008A1 - Liquid aqueous bleaching compositions comprising a sulphonated anionic surfactant

Info

Publication number: EP1001008A1
Application number: EP98870251A
Authority: EP
Inventors: Vincentius Henricus Adrianus Maria Van Spaendonk; Leo Gagliardi; Stefano Scialla
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1998-11-10
Filing date: 1998-11-10
Publication date: 2000-05-17
Also published as: WO2000027971A1; CO5210993A1; AU2147700A; PE20001224A1

Abstract

The present invention relates to a liquid composition having a pH of below 7 and comprising a peroxygen bleach, a sulphonated anionic surfactant and a second surfactant wherein the weight ratio of the sulphonated anionic surfactant to the second surfactant is less than or equal to one. This composition is suitable to deliver excellent stain removal performance.

Description

Technical field

The present invention relates to liquid bleaching compositions. Said compositions are suitable for use in various laundry applications, e.g., as laundry pretreater. More particularly, the compositions herein are suitable for use on various fabrics to provide stain removal and bleaching performance.

Background of the invention

Bleach-containing compositions for bleaching fabrics, are well known in the art.
Liquid peroxygen bleach-containing compositions have been extensively described in the art, especially in laundry applications as laundry detergents, laundry additives or laundry pretreaters.
Indeed, it is known to use such peroxygen bleach-containing compositions in laundry applications to boost the removal of encrusted stains/soils and "problem" stains, such as grease, coffee, tea, grass, mud/clay-containing soils, which are otherwise particularly difficult to remove by typical machine washing.
Although, these liquid aqueous bleaching compositions provide some bleaching performance when used to treat a soiled fabric, there is still some room for further improvement regarding the stain removal performance on various stains including for example greasy stains as well as for further improvement on bleaching performance under various conditions, e.g., pretreatment conditions, i.e., when the liquid aqueous composition is applied neat on the fabric to bleach before the fabric is subsequently rinsed or washed then rinsed with water.
It is known that the stain removal performance of liquid aqueous peroxygen bleach-containing compositions may be improved by the addition of a surfactant or a surfactant system. For example liquid bleaching compositions comprising a peroxygen bleach, an ethoxylated nonionic surfactant, a zwitterionic betaine surfactant and a hydrotrope, as disclosed in European patent application number 97870152.2.
However, there are some limitations to the convenience of said liquid bleaching compositions comprising a surfactant or a surfactant system. In particular, it is well-known from consumer research that the stain removal performance of said compositions is not yet satisfactory, although said compositions comprise a surfactant or a surfactant system.
It is therefore an object of the present invention to provide a liquid bleaching composition whereby said composition shows good stain removal performance.
It has now been found that this object can be efficiently met by formulating a liquid bleaching composition comprising a peroxygen bleach and a surfactant system as described herein.
Indeed, such compositions when used to treat fabrics boost the stain removal performance of various types of stains including greasy stains and/or enzymatic stains as compared to the stain removal delivered by the same compositions comprising no or another surfactant system.
Advantageously, the bleaching compositions as described herein also provide excellent bleaching performance.
More particularly, the compositions of the present invention provide excellent bleaching performance when used in any laundry application, e.g., as a laundry detergent or a laundry additive, and especially when used as a laundry pretreater, or even in other household applications like in hard surface cleaning applications.
A further advantage of the bleaching compositions according to the present invention is that they are able to perform in a variety of conditions, i.e., in hard and soft water as well as when used neat or diluted.
Yet another advantage of the bleaching compositions comprising a surfactant system as described herein is that the raw materials of said surfactant system are cheaper compared to the raw materials for other surfactant systems.

Background art

Bleaching compositions comprising peroxygen bleach and polymers as described herein are well known in the art.
European patent application number 97870152.2 discloses liquid bleaching compositions comprising a peroxygen bleach, an ethoxylated nonionic surfactant, a zwitterionic betaine surfactant and a hydrotrope.

Summary of the invention

The present invention encompasses a liquid composition having a pH of below 7 and comprising a peroxygen bleach, a sulphonated anionic surfactant and a second surfactant wherein the weight ratio of the sulphonated anionic surfactant to the second surfactant is less than or equal to one.
In a preferred embodiment said sulphonated anionic surfactant is a paraffin sulphonate surfactant.
The present invention further encompasses processes of treating surfaces, e.g., a fabric or a hard-surface, starting from a liquid composition as defined herein. For example, the processes of treating fabrics include the steps of contacting said fabrics with the liquid composition herein neat or diluted, and subsequently rinsing said fabrics. In a preferred embodiment, when the fabrics are "pretreated", the composition is applied neat on the fabrics, and the fabrics are subsequently washed in a normal wash cycle.
Additionally, the present invention encompasses the use of a sulphonated anionic surfactant in a liquid composition having a pH below 7 to treat fabrics whereby said compositions provide stain removal benefits.

Detailed description of the invention

The liquid bleaching composition

The compositions according to the present invention are formulated as liquids as opposed to a solid or a gas. 'Liquids' includes gel and paste form.
Preferred compositions of the present invention have a viscosity of 0.1 cps or greater, more preferably of from 0.1 cps to 2000 cps, even more preferably of from 1 cps to 200 cps and most preferably of from 1 cps to 20 cps at 20°C when measured with a Brookfield viscometer at 50 rpm with a spindle n°3.
Preferred liquid compositions of the present invention are aqueous and therefore, preferably comprise water, more preferably comprise water in an amount of from 60% to 98%, even more preferably of from 70% to 97% and most preferably 80% to 97% by weight of the total composition.
The liquid compositions according to the present invention have a pH of below 7, preferably a pH from 1 to 6, more preferably a pH from 2 to 5, and most preferably from 2.5 to 4. In a preferred embodiment the compositions according to the present invention are formulated in the acidic pH range, which contributes to the chemical stability of the compositions and to the stain removal performance of the compositions. The pH of the compositions may be adjusted by any acidifying agent known to those skilled in the art. Examples of acidifying agents are organic acids such as citric acid and inorganic acids such as sulphuric acid.

Peroxygen bleach

As a first essential element the compositions according to the present invention comprise a peroxygen bleach or a mixture thereof. Indeed, the presence of a peroxygen bleach contributes to the excellent bleaching benefits of said compositions.
Suitable peroxygen bleaches to be used herein are selected from the group consisting of : hydrogen peroxide; water soluble sources of hydrogen peroxide; organic or inorganic peracids; hydroperoxides; diacyl peroxides; and mixtures thereof.
As used herein a hydrogen peroxide source refers to any compound that produces perhydroxyl ions when said compound is in contact with water. Suitable water-soluble sources of hydrogen peroxide for use herein include percarbonates, perborates and persilicates and mixtures thereof.
Suitable diacyl peroxides for use herein include aliphatic, aromatic and aliphatic-aromatic diacyl peroxides, and mixtures thereof.
Suitable aliphatic diacyl peroxides for use herein are dilauroyl peroxide, didecanoyl peroxide, dimyristoyl peroxide, or mixtures thereof. A suitable aromatic diacyl peroxide for use herein is for example benzoyl peroxide. A suitable aliphatic-aromatic diacyl peroxide for use herein is for example lauroyl benzoyl peroxide. Such diacyl peroxides have the advantage to be particularly safe to fabrics and color while delivering excellent bleaching performance when used in any laundry application.
Suitable organic or inorganic peracids for use herein include : persulphates such as monopersulfate; peroxyacids such as diperoxydodecandioic acid (DPDA); magnesium perphthalic acid; perlauric acid; perbenzoic and alkylperbenzoic acids; and mixtures thereof.
Suitable hydroperoxides for use herein are tert-butyl hydroperoxide, cumyl hydroperoxide, 2,4,4-trimethylpentyl-2-hydroperoxide, di-isopropylbenzene-monohydroperoxide, tert-amyl hydroperoxide and 2,5-dimethyl-hexane-2,5-dihydroperoxide and mixtures thereof. Such hydroperoxides have the advantage to be particularly safe to fabrics and color while delivering excellent bleaching performance when used in any laundry application.
Preferred peroxygen bleaches herein are selected from the group consisting of : hydrogen peroxide; water soluble sources of hydrogen peroxide; organic or inorganic peracids; hydroperoxides; and diacyl peroxides; and mixtures thereof. More preferred peroxygen bleaches herein are selected from the group consisting of hydrogen peroxide and diacyl peroxides and mixtures thereof. Even more preferred peroxygen bleaches herein are selected from the group consisting of hydrogen peroxide, aliphatic diacyl peroxides, aromatic diacyl peroxides and aliphatic-aromatic diacyl peroxides and mixtures thereof.
Typically, the compositions herein may comprise from 0.01 % to 20%, preferably from 0.3% to 15% and more preferably from 0.5% to 10% by weight of the total composition of said peroxygen bleach or a mixture thereof.

Sulphonated anionic surfactant

As a second essential ingredient the compositions according to the present invention comprise a sulphonated anionic surfactant.
Suitable sulphonated anionic surfactants for use herein are all those commonly known by those skilled in the art. Preferably, the sulphonated anionic surfactants for use herein include alkyl sulphonates, alkyl aryl sulphonates, naphthalene sulphonates, alkyl alkoxylated sulphonates, C₆-C₂₀ alkyl alkoxylated linear or branched diphenyl oxide disulphonates, or mixtures thereof.
Suitable alkyl sulphonates for use herein include water-soluble salts or acids of the formula RSO₃M wherein R is a C₆-C₂₀ linear or branched, saturated or unsaturated alkyl group, preferably a C₈-C₁₈ alkyl group and more preferably a C₁₄-C₁₇ alkyl group, and M is H or a cation, e.g., an alkali metal cation (e.g., sodium, potassium, lithium), or ammonium or substituted ammonium (e.g., methyl-, dimethyl-, and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethyl-ammonium and dimethyl piperdinium cations and quaternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like).
Suitable alkyl aryl sulphonates for use herein include water-soluble salts or acids of the formula RSO₃M wherein R is an aryl, preferably a benzyl, substituted by a C₆-C₂₀ linear or branched saturated or unsaturated alkyl group, preferably a C₈-C₁₈ alkyl group and more preferably a C₁₀-C₁₆ alkyl group, and M is H or a cation, e.g., an alkali metal cation (e.g., sodium, potassium, lithium, calcium, magnesium and the like) or ammonium or substituted ammonium (e.g., methyl-, dimethyl-, and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethyl-ammonium and dimethyl piperdinium cations and quaternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like).
Particularly suitable linear alkyl sulphonates include C₁₄-C₁₇ paraffin sulphonate like Hostapur ® SAS commercially available from Hoechst. An example of commercially available alkyl aryl sulphonate is Lauryl aryl sulphonate from Su.Ma.. Particularly preferred alkyl aryl sulphonates are alkyl benzene sulphonates commercially available under trade name Nansa® available from Albright&Wilson.
By "linear alkyl sulphonate" it is meant herein a non-substituted alkyl sulphonate wherein the alkyl chain comprises from 6 to 20 carbon atoms, preferably from 8 to 18 carbon atoms, and more preferably from 14 to 17 carbon atoms, and wherein this alkyl chain is sulphonated at one terminus.
Suitable alkoxylated sulphonate surfactants for use herein are according to the formula R(A)_mSO₃M wherein R is an unsubstituted C₆-C₂₀ alkyl, hydroxyalkyl or alkyl aryl group, having a linear or branched C₆-C₂₀ alkyl component, preferably a C₁₂-C₂₀ alkyl or hydroxyalkyl, more preferably C₁₂-C₁₈ alkyl or hydroxyalkyl, A is an ethoxy or propoxy or butoxy unit, m is greater than zero, typically between 0.5 and 6, more preferably between 0.5 and 3, and M is H or a cation which can be, for example, a metal cation (e.g., sodium, potassium, lithium, calcium, magnesium, etc.), ammonium or substituted-ammonium cation. Alkyl ethoxylated sulphonates, alkyl butoxylated sulphonates as well as alkyl propoxylated sulphonates are contemplated herein. Specific examples of substituted ammonium cations include methyl-, dimethyl-, trimethyl-ammonium and quaternary ammonium cations, such as tetramethyl-ammonium, dimethyl piperdinium and cations derived from alkanolamines such as ethylamine, diethylamine, triethylamine, mixtures thereof, and the like. Exemplary surfactants are C₁₂-C₁₈ alkyl polyethoxylate (1.0) sulphonate (C₁₂-C₁₈E(1.0)SM), C₁₂-C₁₈ alkyl polyethoxylate (2.25) sulphonate (C₁₂-C₁₈E(2.25)SM), C₁₂-C₁₈ alkyl polyethoxylate (3.0) sulphonate (C₁₂-C₁₈E(3.0)SM), and C₁₂-C₁₈ alkyl polyethoxylate (4.0) sulphonate (C₁₂-C₁₈E(4.0)SM), wherein M is conveniently selected from sodium and potassium. Particularly suitable alkoxylated sulphonate include alkyl aryl polyether sulphonate like Triton X-200® commercially available from Union Carbide.
Suitable C₆-C₂₀ alkyl alkoxylated linear or branched diphenyl oxide disulphonate surfactants for use herein are according to the following formula:
wherein R is a C₆-C₂₀ linear or branched, saturated or unsaturated alkyl group, preferably a C₁₂-C₁₈ alkyl group and more preferably a C₁₄-C₁₆ alkyl group, and X+ is H or a cation, e.g., an alkali metal cation (e.g., sodium, potassium, lithium, calcium, magnesium and the like). Particularly suitable C₆-C₂₀ alkyl alkoxylated linear or branched diphenyl oxide disulphonate surfactants to be used herein are the C₁₂ branched di phenyl oxide disulphonic acid and C₁₆ linear di phenyl oxide disulphonate sodium salt respectively commercially available by DOW under the trade name Dowfax 2A1® and Dowfax 8390®.
Preferably said sulphonated anionic surfactant for use herein is selected from the group consisting of : alkyl sulphonates; alkyl aryl sulphonates; alkyl alkoxylated sulphonates; C₆-C₂₀ alkyl alkoxylated linear or branched diphenyl oxide disulphonates; naphthalene sulphonates; and mixtures thereof. More preferably said sulphonated anionic surfactant for use herein is an alkyl sulphonate. Even more preferably said sulphonated anionic surfactant for use herein is an paraffin sulphonate. Most preferably said sulphonated anionic surfactant for use herein is a C₁₄-C₁₇ paraffin sulphonate.
Typically, the compositions according to the present invention comprise from 0.01% to 25%, preferably from 0.1% to 15% and more preferably from 0.5% to 7% by weight of the total composition of a sulphonated anionic surfactant.
The weight ratio of sulphonated anionic surfactant to second surfactant is less than or equal to one, preferably said weight ratio of the sulphonated anionic surfactant to the second surfactant is from 0.02 to 1, more preferably from 0.04 to 0.9, even more preferably from 0.075 to 0.5 and most preferably from 0.1 to 0.2.
Another aspect of the present invention is the use of a sulphonated anionic surfactant as described above in a liquid composition having a pH below 7 to treat fabrics whereby said compositions provide stain removal benefits.

Second surfactant

As a third essential ingredient the compositions according to the present invention comprise a second surfactant.
Typically, the compositions according to the present invention comprise from 0.01% to 25%, preferably from 1% to 25 % and more preferably from 3% to 20% by weight of the total composition of a second surfactant.
Suitable as second surfactant to be used herein is a surfactant selected from the group consisting of nonionic surfactants, amphoteric surfactants, zwitterionic surfactants and mixtures thereof.
Suitable nonionic surfactants are alkoxylated nonionic surfactants. Preferred alkoxylated nonionic surfactants herein are ethoxylated nonionic surfactants according to the formula RO-(C₂H₄O)_nH, wherein R is a C₆ to C₂₂ alkyl chain or a C₆ to C₂₈ alkyl benzene chain, and wherein n is from 0 to 20, preferably from 1 to 15 and, more preferably from 2 to 15 and most preferably from 2 to 12. The preferred R chains for use herein are the C8 to C22 alkyl chains. Propoxylated nonionic surfactants butoxylated nonionic surfactants, ethoxy/propoxylated, ethoxy/butoxylated, propoxy/butoxylated and ethoxy/butoxy/propoxylated ones may also be used herein instead of the ethoxylated nonionic surfactants as defined herein above or together with said surfactants
Preferred ethoxylated nonionic surfactants are according to the formula above and have an HLB (hydrophilic-lipophilic balance) below 16, preferably below 15, and more preferably below 14. Those ethoxylated nonionic surfactants have been found to provide good grease cutting properties.
Accordingly suitable ethoxylated nonionic surfactants for use herein are Dobanol® 91-2.5 (HLB= 8.1; R is a mixture of C9 and C₁₁ alkyl chains, n is 2.5), or Lutensol® TO3 (HLB=8; R is a C₁₃ alkyl chains, n is 3), or Lutensol® AO3 (HLB=8; R is a mixture of C₁₃ and C₁₅ alkyl chains, n is 3), or Tergitol® 25L3 (HLB= 7.7; R is in the range of C₁₂ to C₁₅ alkyl chain length, n is 3), or Dobanol® 23-3 (HLB=8.1; R is a mixture of C₁₂ and C₁₃ alkyl chains, n is 3), or Dobanol® 23-2 (HLB=6.2; R is a mixture of C₁₂ and C₁₃ alkyl chains, n is 2), or Dobanol® 45-7 (HLB=11.6; R is a mixture of C₁₄ and C₁₅ alkyl chains, n is 7) Dobanol® 23-6.5 (HLB=11.9; R is a mixture of C₁₂ and C₁₃ alkyl chains, n is 6.5), or Dobanol® 25-7 (HLB=12; R is a mixture of C₁₂ and C₁₅ alkyl chains, n is 7), or Dobanol® 91-5 (HLB=11.6; R is a mixture of C₉ and C₁₁ alkyl chains, n is 5), or Dobanol® 91-6 (HLB=12.5 ; R is a mixture of C₉ and C₁₁ alkyl chains, n is 6), or Dobanol® 91-8 (HLB=13.7 ; R is a mixture of C₉ and C₁₁ alkyl chains, n is 8), Dobanol® 91-10 (HLB=14.2 ; R is a mixture of C₉ to C₁₁ alkyl chains, n is 10), Dobanol® 91-12 (HLB=14.5 ; R is a mixture of C₉ to C₁₁ alkyl chains, n is 12), or mixtures thereof. Preferred herein are Dobanol® 91-2.5 , or Lutensol® TO3, or Lutensol® AO3, or Tergitol® 25L3, or Dobanol® 23-3, or Dobanol® 23-2, or Dobanol® 45-7, Dobanol® 91-8, or Dobanol® 91-10, or Dobanol® 91-12, or mixtures thereof. These Dobanol® surfactants are commercially available from SHELL. These Lutensol® surfactants are commercially available from BASF and these Tergitol® surfactants are commercially available from UNION CARBIDE.
Suitable chemical processes for preparing the alkoxylated nonionic surfactants for use herein include condensation of corresponding alcohols with alkylene oxide, in the desired proportions. Such processes are well-known to the man skilled in the art and have been extensively described in the art.
The compositions herein may desirably comprise one of those ethoxylated nonionic surfactants or a mixture of those ethoxylated nonionic surfactants having different HLBs (hydrophilic-lipophilic balance). In a preferred embodiment the compositions herein comprise an ethoxylated nonionic surfactant according to the above formula and having an HLB up to 10 (i.e., a so called hydrophobic ethoxylated nonionic surfactant), preferably below 10, more preferably below 9, and an ethoxylated nonionic surfactant according to the above formula and having an HLB above 10 to 16 (i.e., a so called hydrophilic ethoxylated nonionic surfactant), preferably from 11 to 14. Indeed, in this preferred embodiment the compositions of the present invention typically comprise from 0.01% to 15% by weight of the total composition of said hydrophobic ethoxylated nonionic surfactant, preferably from 0.5% to 10% and from 0.01% to 15% by weight of said hydrophilic ethoxylated nonionic surfactant, preferably from 0.5% to 10%. Such mixtures of ethoxylated nonionic surfactants with different HLBs may be desired as they allow optimum grease cleaning removal performance on a broader range of greasy soils having different hydrophobic/hydrophilic characters.
Other suitable nonionic surfactants to be used herein include polyhydroxy fatty acid amide surfactants, or mixtures thereof, according to the formula: R² - C(O) - N(R¹) - Z, wherein R¹ is H, or C_1-C₄ alkyl, C_1-C₄ hydrocarbyl, 2-hydroxy ethyl, 2-hydroxy propyl or a mixture thereof, R² is C_5-C₃₁ hydrocarbyl, and Z is a polyhydroxyhydrocarbyl having a linear hydrocarbyl chain with at least 3 hydroxyls directly connected to the chain, or an alkoxylated derivative thereof.
Preferably, R¹ is C_1-C₄ alkyl, more preferably C₁ or C₂ alkyl and most preferably methyl, R² is a straight chain C_7-C₁₉ alkyl or alkenyl, preferably a straight chain C_9-C₁₈ alkyl or alkenyl, more preferably a straight chain C_11-C₁₈ alkyl or alkenyl, and most preferably a straight chain C_11-C₁₄ alkyl or alkenyl, or mixtures thereof. Z preferably will be derived from a reducing sugar in a reductive amination reaction; more preferably Z is a glycityl. Suitable reducing sugars include glucose, fructose, maltose, lactose, galactose, mannose and xylose. As raw materials, high dextrose corn syrup, high fructose corn syrup, and high maltose corn syrup can be utilized as well as the individual sugars listed above. These corn syrups may yield a mix of sugar components for Z. It should be understood that it is by no means intended to exclude other suitable raw materials. Z preferably will be selected from the group consisting of -CH₂-(CHOH)_n-CH₂OH, -CH(CH₂OH)-(CHOH)_n-1-CH₂OH, -CH₂-(CHOH)₂-(CHOR')(CHOH)-CH₂OH, where n is an integer from 3 to 5, inclusive, and R' is H or a cyclic or aliphatic monosaccharide, and alkoxylated derivatives thereof. Most preferred are glycityls wherein n is 4, particularly CH₂-(CHOH)₄-CH₂OH.
In formula R² - C(O) - N(R¹) - Z, R¹ can be, for example, N-methyl, N-ethyl, N-propyl, N-isopropyl, N-butyl, N-2-hydroxy ethyl, or N-2-hydroxy propyl. R² - C(O) - N< can be, for example, cocamide, stearamide, oleamide, lauramide, myristamide, capricamide, palmitamide, tallowamide and the like. Z can be 1-deoxyglucityl, 2-deoxyfructityl, 1-deoxymaltityl, 1-deoxylactityl, 1-deoxygalactityl, 1-deoxymannityl, 1-deoxymaltotriotityl and the like.
Suitable polyhydroxy fatty acid amide surfactants to be used herein may be commercially available under the trade name HOE® from Hoechst.
Methods for making polyhydroxy fatty acid amide surfactants are known in the art. In general, they can be made by reacting an alkyl amine with a reducing sugar in a reductive amination reaction to form a corresponding N-alkyl polyhydroxyamine, and then reacting the N-alkyl polyhydroxyamine with a fatty aliphatic ester or triglyceride in a condensation/amidation step to form the N-alkyl, N-polyhydroxy fatty acid amide product. Processes for making compositions containing polyhydroxy fatty acid amides are disclosed for example in GB patent specification 809,060, published February 18, 1959, by Thomas Hedley & Co., Ltd., US patent 2,965,576, issued December 20, 1960 to E.R. Wilson, US patent 2,703,798, Anthony M. Schwartz, issued March 8, 1955, US patent 1,985,424, issued December 25, 1934 to Piggott and WO92/06070, each of which is incorporated herein by reference.
Suitable amphoteric surfactants to be used herein include amine oxides having the following formula R₁R₂R₃NO wherein each of R₁, R₂ and R₃ is independently a saturated substituted or unsubstituted, linear or branched hydrocarbon chains of from 1 to 30 carbon atoms. Preferred amine oxide surfactants to be used according to the present invention are amine oxides having the following formula R₁R₂R₃NO wherein R₁ is an hydrocarbon chain comprising from 1 to 30 carbon atoms, preferably from 6 to 20, more preferably from 8 to 16, most preferably from 8 to 12 carbon atoms, and wherein R₂ and R₃ are independently substituted or unsubstituted, linear or branched hydrocarbon chains comprising from 1 to 4 carbon atoms, preferably from 1 to 3 carbon atoms, and more preferably are methyl groups. R₁ may be a saturated substituted or unsubstituted linear or branched hydrocarbon chain. Suitable amine oxides for use herein are for instance natural blend C₈-C₁₀ amine oxides as well as C₁₂-C₁₆ amine oxides commercially available from Hoechst.
Suitable zwitterionic surfactants include zwitterionic betaine surfactants.
Suitable zwitterionic betaine surfactants for use herein contain both a cationic hydrophilic group, i.e., a quaternary ammonium group, and anionic hydrophilic group on the same molecule at a relatively wide range of pH's. The typical anionic hydrophilic groups are carboxylates and suiphonates, although other groups like sulfates, phosphonates, and the like can be used. A generic formula for the zwitterionic betaine surfactant to be used herein is : R₁-N⁺(R₂)(R₃)R₄X^- wherein R₁ is a hydrophobic group; R₂ is hydrogen, C₁-C₆ alkyl, hydroxy alkyl or other substituted C₁-C₆ alkyl group; R₃ is C₁-C₆ alkyl, hydroxy alkyl or other substituted C₁-C₆ alkyl group which can also be joined to R₂ to form ring structures with the N, or a C₁-C₆ sulphonate group; R₄ is a moiety joining the cationic nitrogen atom to the hydrophilic group and is typically an alkylene, hydroxy alkylene, or polyalkoxy group containing from 1 to 10 carbon atoms; and X is the hydrophilic group, which is a carboxylate or sulphonate group.
Preferred hydrophobic groups R₁ are aliphatic or aromatic, saturated or unsaturated, substituted or unsubstituted hydrocarbon chains that can contain linking groups such as amido groups, ester groups. More preferred R₁ is an alkyl group containing from 1 to 24 carbon atoms, preferably from 8 to 18, and more preferably from 10 to 16 carbon atoms. These simple alkyl groups are preferred for cost and stability reasons. However, the hydrophobic group R₁ can also be an amido radical of the formula R_a-C(O)-NH-(C(R_b)₂)_m, wherein R_a is an aliphatic or aromatic, saturated or unsaturated, substituted or unsubstituted hydrocarbon chain, preferably an alkyl group containing from 8 up to 20 carbon atoms, preferably up to 18, more preferably up to 16 carbon atoms, R_b is selected from the group consisting of hydrogen and hydroxy groups, and m is from 1 to 4, preferably from 2 to 3, more preferably 3, with no more than one hydroxy group in any (C(R_b)₂) moiety.
Preferred R₂ is hydrogen, or a C₁-C₃ alkyl and more preferably methyl. Preferred R₃ is C₁-C₄ sulphonate group, or a C₁-C₃ alkyl and more preferably methyl. Preferred R₄ is (CH₂)_n wherein n is an integer from 1 to 10, preferably from 1 to 6, more preferably is from 1 to 3.
Some common examples of betaine/sulphobetaine are described in U.S. Pat. Nos. 2,082,275, 2,702,279 and 2,255,082, incorporated herein by reference.
Examples of particularly suitable alkyldimethyl betaines include coconut-dimethyl betaine, lauryl dimethyl betaine, decyl dimethyl betaine, 2-(N-decyl-N, N-dimethyl-ammonia)acetate, 2-(N-coco N, N-dimethylammonio) acetate, myristyl dimethyl betaine, palmityl dimethyl betaine, cetyl dimethyl betaine, stearyl dimethyl betaine. For example Coconut dimethyl betaine is commercially available from Seppic under the trade name of Amonyl 265®. Lauryl betaine is commercially available from Albright & Wilson under the trade name Empigen BB/L®.
Examples of amidobetaines include cocoamidoethylbetaine, cocoamidopropyl betaine or C₁₀-C₁₄ fatty acylamidopropylene(hydropropylene)sulfobetaine. For example C₁₀-C₁₄ fatty acylamidopropylene(hydropropylene)sulfobetaine is commercially available from Sherex Company under the trade name "Varion CAS® sulfobetaine".
A further example of betaine is Lauryl-immino-dipropionate commercially available from Rhone-Poulenc under the trade name Mirataine H₂C-HA®.
Preferably said second surfactant is a surfactant selected from the group consisting of nonionic surfactants, amphoteric surfactants, zwitterionic surfactants and mixtures thereof. More preferably said second is a nonionic surfactant. Even more preferably said second surfactant is an alkoxylated nonionic surfactant.
A significant co-operation has been observed between a sulphonated anionic surfactant and a second surfactant, preferably a nonionic surfactant, in a peroxygen bleach-containing composition to get optimum stain removal performance on a variety of soils, from particulate to non-particulate soils from hydrophobic to hydrophilic soils under any household application and especially laundry application on both hydrophilic and hydrophobic fabrics.
More particularly, the present invention is based on the finding that liquid composition comprising a peroxygen bleach, a sulphonated anionic surfactant and a second surfactant, show an excellent stain removal performance of various types of stains including greasy stains (e.g., lipstick, olive oil, mayonnaise, vegetal oil, sebum, make-up), as compared to the stain removal performance delivered by other compositions comprising a peroxygen bleach and no or another surfactant system at equal total level of surfactants.
Additionally, due to the presence of a peroxygen bleach, the bleaching compositions as described herein also provide excellent bleaching performance.
The stain removal performance may be evaluated by the following test methods on various type of stains.
A suitable test method for evaluating the stain removal performance on a soiled fabric under pretreatment condition is the following: A composition according to the present invention is applied neat to a fabric preferably to the soiled portion of the fabric, left to act from 1 to 10 minutes, and said pretreated fabric is then washed according to common washing conditions, at a temperature of from 30° to 70°C for from 10 to 100 minutes. The stain removal is then evaluated by comparing side by side the soiled fabric pretreated with the composition of the present invention with those pretreated with the reference, e.g., the same composition but no or another surfactant system. A visual grading may be used to assign difference in panel units (psu) in a range from 0 to 4.
The bleaching performance may be evaluated as for the stain removal performance but the stains used are bleachable stains like coffee, tea and the like.

Optional ingredients

The compositions herein may further comprise a variety of other optional ingredients such as chelating agents, builders, other surfactants, hydrotropes, stabilisers, bleach activators, solvents, soil suspenders, soil suspending polyamine polymers, soil release agents, foam reducing systems, radical scavengers, antioxidant, catalysts, dye transfer inhibitors, rheology modifiers, brighteners, perfumes, pigments and dyes.

Other surfactants

The compositions of the present invention may further comprise other surfactants than the ones mentioned herein before including other anionic surfactants and/or cationic surfactants.
Typically, the compositions according to the present invention may comprise from 0.01% to 30%, preferably from 0.1% to 25 % and more preferably from 0.5% to 20% by weight of the total composition of another surfactant on top of the sulphonated anionic surfactant and the second surfactant.
Suitable other anionic surfactants to be used in the compositions herein include water-soluble salts or acids of the formula ROSO₃M wherein R preferably is a C₁₀-C₂₄ hydrocarbyl, preferably an alkyl or hydroxyalkyl having a C₁₀-C₂₀ alkyl component, more preferably a C₁₂-C₁₈ alkyl or hydroxyalkyl, and M is H or a cation, e.g., an alkali metal cation (e.g., sodium, potassium, lithium), or ammonium or substituted ammonium (e.g., methyl-, dimethyl-, and trimethyl ammonium cations and quaternary ammonium cations, such as tetramethyl-ammonium and dimethyl piperdinium cations and quaternary ammonium cations derived from alkylamines such as ethylamine, diethylamine, triethylamine, and mixtures thereof, and the like). Typically, alkyl chains of C₁₂-₁₆ are preferred for lower wash temperatures (e.g., below 50°C) and C₁₆-₁₈ alkyl chains are preferred for higher wash temperatures (e.g., above 50°C).
Other suitable other anionic surfactants for use herein are water-soluble salts or acids of the formula RO(A)_mSO₃M wherein R is an unsubstituted C₁₀-C₂₄ alkyl or hydroxyalkyl group having a C₁₀-C₂₄ alkyl component, preferably a C₁₂-C₂₀ alkyl or hydroxyalkyl, more preferably C₁₂-C₁₈ alkyl or hydroxyalkyl, A is an ethoxy or propoxy unit, m is greater than zero, typically between 0.5 and 6, more preferably between 0.5 and 3, and M is H or a cation which can be, for example, a metal cation (e.g., sodium, potassium, lithium, calcium, magnesium, etc.), ammonium or substituted-ammonium cation. Alkyl ethoxylated sulfates as well as alkyl propoxylated sulfates are contemplated herein. Specific examples of substituted ammonium cations include methyl-, dimethyl-, trimethyl-ammonium and quaternary ammonium cations, such as tetramethyl-ammonium, dimethyl piperdinium and cations derived from alkanolamines such as ethylamine, diethylamine, triethylamine, mixtures thereof, and the like. Exemplary surfactants are C₁₂-C₁₈ alkyl polyethoxylate (1.0) sulfate, (C₁₂-C₁₈E(1.0)SM), C₁₂-C₁₈ alkyl polyethoxylate (2.25) sulfate (C₁₂-C₁₈E(2.25)SM), C₁₂-C₁₈ alkyl polyethoxylate (3.0) sulfate (C₁₂-C₁₈E(3.0)SM), and C₁₂-C₁₈ alkyl polyethoxylate (4.0) sulfate (C₁₂-C₁₈E(4.0)SM), wherein M is conveniently selected from sodium and potassium.
Other suitable anionic surfactants to be used herein also include acyl sarcosinate or mixtures thereof, in its acid and/or salt form, preferably long chain acyl sarcosinates having the following formula:
wherein M is hydrogen or a cationic moiety and wherein R is an alkyl group of from 11 to 15 carbon atoms, preferably of from 11 to 13 carbon atoms. Preferred M are hydrogen and alkali metal salts, especially sodium and potassium. Said acyl sarcosinate surfactants are derived from natural fatty acids and the amino-acid sarcosine (N-methyl glycine). They are suitable to be used as aqueous solution of their salt or in their acidic form as powder. Being derivatives of natural fatty acids, said acyl sarcosinates are rapidly and completely biodegradable and have good skin compatibility.
Accordingly, suitable long chain acyl sarcosinates to be used herein include C₁₂ acyl sarcosinate (i.e., an acyl sarcosinate according to the above formula wherein M is hydrogen and R is an alkyl group of 11 carbon atoms) and C₁₄ acyl sarcosinate (i.e., an acyl sarcosinate according to the above formula wherein M is hydrogen and R is an alkyl group of 13 carbon atoms). C₁₂ acyl sarcosinate is commercially available, for example, as Hamposyl L-30® supplied by Hampshire. C₁₄ acyl sarcosinate is commercially available, for example, as Hamposyl M-30® supplied by Hampshire.

Hydrotropes

As an optional ingredient the compositions according to the present invention may comprise a hydrotrope.
Suitable hydrotropes herein include sulphonated hydrotropes. Any sulphonated hydrotropes known to those skilled in the art are suitable for use herein. In a preferred embodiment alkyl aryl sulphonates or alkyl aryl sulphonic acids are used. Preferred alkyl aryl sulphonates include sodium, potassium, calcium and ammonium xylene sulphonates, sodium, potassium, calcium and ammonium toluene sulphonates, sodium, potassium, calcium and ammonium cumene sulphonates, sodium, potassium, calcium and ammonium substituted or unsubstituted naphthalene sulphonates and mixtures thereof. Preferred alkyl aryl sulphonic acids include xylenesulphonic acid, toluenesulphonic acid, cumenesulphonic acid, substituted or unsubstituted naphthalenesulphonic acid and mixtures thereof. More preferably, xylenesulphonic acid or p-toluene sulphonate or mixtures thereof are used.
Typically, the compositions herein may comprise from 0.01% to 20%, preferably from 0.05% to 10% and more preferably from 0.1% to 5% by weight of the total composition of a sulphonated hydrotrope.
The sulphonated hydrotrope, when present, contributes to the physical and chemical stability of the compositions as described herein.

Chelating agents

The compositions of the present invention may comprise a chelating agent as a preferred optional ingredient. Suitable chelating agents may be any of those known to those skilled in the art such as the ones selected from the group comprising phosphonate chelating agents, amino carboxylate chelating agents, other carboxylate chelating agents, polyfunctionally-substituted aromatic chelating agents, ethylenediamine N,N'- disuccinic acids, or mixtures thereof.
A chelating agent may be desired in the compositions of the present invention as it allows to increase the ionic strength of the compositions herein and thus their stain removal and bleaching performance on various surfaces. The presence of chelating agents may also contribute to reduce the tensile strength loss of fabrics and/or color damage, especially in a laundry pretreatment application. Indeed, the chelating agents inactivate the metal ions present on the surface of the fabrics and/or in the cleaning compositions (neat or diluted) that otherwise would contribute to the radical decomposition of the peroxygen bleach.
Suitable phosphonate chelating agents to be used herein may include alkali metal ethane 1-hydroxy diphosphonates (HEDP), alkylene poly (alkylene phosphonate), as well as amino phosphonate compounds, including amino aminotri(methylene phosphonic acid) (ATMP), nitrilo trimethylene phosphonates (NTP), ethylene diamine tetra methylene phosphonates, and diethylene triamine penta methylene phosphonates (DTPMP). The phosphonate compounds may be present either in their acid form or as salts of different cations on some or all of their acid functionalities. Preferred phosphonate chelating agents to be used herein are diethylene triamine penta methylene phosphonate (DTPMP) and ethane 1-hydroxy diphosphonate (HEDP). Such phosphonate chelating agents are commercially available from Monsanto under the trade name DEQUEST®.
Polyfunctionally-substituted aromatic chelating agents may also be useful in the compositions herein. See U.S. patent 3,812,044, issued May 21, 1974, to Connor et al. Preferred compounds of this type in acid form are dihydroxydisulfobenzenes such as 1,2-dihydroxy -3,5-disulfobenzene.
A preferred biodegradable chelating agent for use herein is ethylene diamine N,N'- disuccinic acid, or alkali metal, or alkaline earth, ammonium or substitutes ammonium salts thereof or mixtures thereof. Ethylenediamine N,N'- disuccinic acids, especially the (S,S) isomer, have been extensively described in US patent 4, 704, 233, November 3, 1987, to Hartman and Perkins. Ethylenediamine N,N'- disuccinic acid is, for instance, commercially available under the tradename ssEDDS® from Palmer Research Laboratories.
Suitable amino carboxylates to be used herein include ethylene diamine tetra acetates, diethylene triamine pentaacetates, diethylene triamine pentaacetate (DTPA), N- hydroxyethylethylenediamine triacetates, nitrilotri-acetates, ethylenediamine tetrapropionates, triethylenetetraaminehexa-acetates, ethanol-diglycines, propylene diamine tetracetic acid (PDTA) and methyl glycine di-acetic acid (MGDA), both in their acid form, or in their alkali metal, ammonium, and substituted ammonium salt forms. Particularly suitable amino carboxylates to be used herein are diethylene triamine penta acetic acid, propylene diamine tetracetic acid (PDTA) which is, for instance, commercially available from BASF under the trade name Trilon FS® and methyl glycine di-acetic acid (MGDA).
Further carboxylate chelating agents to be used herein include salicylic acid, aspartic acid, glutamic acid, glycine, malonic acid or mixtures thereof.
Another chelating agent for use herein is of the formula:
wherein R₁, R₂, R₃, and R₄ are independently selected from the group consisting of -H, alkyl, alkoxy, aryl, aryloxy, -Cl, -Br, -NO₂, -C(O)R', and -SO₂R''; wherein R' is selected from the group consisting of -H, -OH, alkyl, alkoxy, aryl, and aryloxy; R'' is selected from the group consisting of alkyl, alkoxy, aryl, and aryloxy; and R₅, R₆, R₇, and R₈ are independently selected from the group consisting of -H and alkyl.
Particularly preferred chelating agents to be used herein are amino aminotri(methylene phosphonic acid), di-ethylene-triamino-pentaacetic acid, diethylene triamine penta methylene phosphonate, 1-hydroxy ethane diphosphonate, ethylenediamine N, N'-disuccinic acid, and mixtures thereof.
Typically, the compositions according to the present invention may comprise up to 5%, preferably from 0.01% to 1.5% by weight and more preferably from 0.01% to 0.5% by weight of the total composition of a chelating agent.

Foam reducing system

The compositions according to the present invention may further comprise a foam reducing agent or a mixture thereof. Any foam reducing agents known to those skilled in the art are suitable for use herein. In a preferred embodiment a foam reducing system comprising a fatty acid together with a capped alkoxylated nonionic surfactant as defined herein after and/or silicone is used.
Typically, the compositions herein may comprise from 1·10^-4% to 10%, preferably from 1·10^-3% to 5% and more preferably from 1·10^-2% to 5% by weight of the total composition of a fatty acid.
Typically, the compositions herein may comprise from 1·10^-3% to 20%, preferably from 1·10^-2% to 10% and more preferably from 5·10^-2% to 5% by weight of the total composition of a capped alkoxylated nonionic surfactant as defined herein.
Typically, the compositions herein may comprise from 1·10^-5% to 5%, preferably from 1·10^-5% to 1% and more preferably from 1·10^-4% to 0.5% by weight of the total composition of a silicone.
Suitable fatty acids for use herein are the alkali salts of a C₈-C₂₄ fatty acid. Such alkali salts include the metal fully saturated salts like sodium, potassium and/or lithium salts as well as the ammonium and/or alkylammonium salts of fatty acids, preferably the sodium salt. Preferred fatty acids for use herein contain from 8 to 22, preferably from 8 to 20 and more preferably from 8 to 18 carbon atoms.
Suitable fatty acids may be selected from caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, and mixtures of fatty acids suitably hardened, derived from natural sources such as plant or animal esters (e.g., palm oil, coconut oil, soybean oil, castor oil, tallow, ground oil, whale and fish oils and/or babassu oil.
For example Coconut Fatty Acid is commercially available from UNICHEMA under the name PRIFAC 5900®.
Suitable capped alkoxylated nonionic surfactants for use herein are according to the formula: R₁(O-CH₂-CH₂)_n-(OR₂)_m-O-R₃
wherein R₁ is a C₈-C₂₄ linear or branched alkyl or alkenyl group, aryl group, alkaryl group, preferably R₁ is a C₈-C₁₈ alkyl or alkenyl group, more preferably a C₁₀-C₁₅ alkyl or alkenyl group, even more preferably a C₁₀-C₁₅ alkyl group;
wherein R₂ is a C₁-C₁₀ linear or branched alkyl group, preferably a C₂-C₁₀ linear or branched alkyl group, preferably a C₃ group;
wherein R₃ is a C₁-C₁₀ alkyl or alkenyl group, preferably a C₁-C₅ alkyl group, more preferably methyl;
and wherein n and m are integers independently ranging in the range of from 1 to 20, preferably from 1 to 10, more preferably from 1 to 5; or mixtures thereof.
These surfactants are commercially available from BASF under the trade name Plurafac®, from HOECHST under the trade name Genapol® or from ICI under the trade name Symperonic®. Preferred capped nonionic alkoxylated surfactants of the above formula are those commercially available under the tradename Genapol® L 2.5 NR from Hoechst, and Plurafac® from BASF.
Suitable silicones for use herein include any silicone and silica-silicone mixtures. Silicones can be generally represented by alkylated polysiloxane materials while silica is normally used in finely divided forms exemplified by silica aerogels and xerogels and hydrophobic silicas of various types. These materials can be incorporated as particulates in which the silicone is advantageously releasably incorporated in a water-soluble or water-dispersible, substantially non-surface-active detergent impermeable carrier. Alternatively, the silicone can be dissolved or dispersed in a liquid carrier and applied by spraying on to one or more of the other components.
Actually in industrial practice, the term "silicone" has become a generic term which encompasses a variety of relatively high-molecular-weight polymers containing siloxane units and hydrocarbyl groups of various types. Indeed, silicone compounds have been extensively described in the art, see for instance US 4 076 648, US 4 021 365, US 4 749 740, US 4 983 316, EP 150 872, EP 217 501 and EP 499 364. The silicone compounds disclosed therein are suitable in the context of the present invention. Generally, the silicone compounds can be described as siloxanes having the general structure :
wherein n is from 20 to 2000, and where each R independently can be an alkyl or an aryl radical. Examples of such substituents are methyl, ethyl, propyl, isobutyl, and phenyl. Preferred polydiorganosiloxanes are polydimethylsiloxanes having trimethylsilyl end blocking units and having a viscosity at 25°C of from 5 x 10^-5 m²/s to 0.1 m²/s, i.e., a value of n in the range 40 to 1500. These are preferred because of their ready availability and their relatively low cost.
A preferred type of silicone compounds useful in the compositions herein comprises a mixture of an alkylated siloxane of the type herein above disclosed and solid silica.
The solid silica can be a fumed silica, a precipitated silica or a silica made by the gel formation technique. The silica particles can be rendered hydrophobic by treating them with diakylsilyl groups and/or trialkylsilane groups either bonded directly onto the silica or by means of silicone resin. A preferred silicone compound comprises a hydrophobic silanated, most preferably trimethylsilanated silica having a particle size in the range from 10 mm to 20 mm and a specific surface area above 50 m²/g. Silicone compounds employed in the compositions according to the present invention suitably have an amount of silica in the range of 1 to 30% (more preferably 2.0 to 15%) by weight of the total weight of the silicone compounds resulting in silicone compounds having an average viscosity in the range of from 2 x 10^-4m²/s to 1m²/s. Preferred silicone compounds may have a viscosity in the range of from 5 x 10^-3m²/s to 0.1m²/s. Particularly suitable are silicone compounds with a viscosity of 2 x 10^-2m²/s or 4.5 x 10^-2m²/s.
Suitable silicone compounds for use herein are commercially available from various companies including Rhone Poulenc, Fueller and Dow Corning. Examples of silicone compounds for use herein are Silicone DB® 100 and Silicone Emulsion 2-3597® both commercially available from Dow Corning.
Another silicone compound is disclosed in Bartollota et al. U.S. Patent 3 933 672. Other particularly useful silicone compounds are the self-emulsifying silicone compounds, described in German Patent Application DTOS 2 646 126 published April 28, 1977. An example of such a compound is DC-544®, commercially available from Dow Corning, which is a siloxane-glycol copolymer.
Typically preferred silicone compounds are described in European Patent application EP-A-573699. Said compositions can comprise a silicone/silica mixture in combination with fumed nonporous silica such as Aerosil®.

Radical scavenger

The compositions of the present invention may comprise a radical scavenger or a mixture thereof. Suitable radical scavengers for use herein include the well-known substituted mono and dihydroxy benzenes and their analogs, alkyl and aryl carboxylates and mixtures thereof. Preferred such radical scavengers for use herein include di-tert-butyl hydroxy toluene (BHT), hydroquinone, di-tert-butyl hydroquinone, mono-tert-butyl hydroquinone, tert-butyl-hydroxy anysole, benzoic acid, toluic acid, catechol, t-butyl catechol, benzylamine, 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl) butane, n-propyl-gallate or mixtures thereof and highly preferred is di-tert-butyl hydroxy toluene. Such radical scavengers like N-propyl-gallate may be commercially available from Nipa Laboratories under the trade name Nipanox S1 ®.
Radical scavengers when used, are typically present herein in amounts ranging up to 10% and preferably from 0.001% to 0.5% by weight of the total composition.
The presence of radical scavengers may contribute to reduce tensile strength loss of fabrics and/or color damage when the compositions of the present invention are used in any laundry application, especially in a laundry pretreatment application.

Antioxidant

The compositions according to the present invention may further comprise an antioxidant.
Typically, the compositions herein may comprise up to 10%, preferably from 0.002% to 5%, more preferably from 0.005% to 2%, and most preferably from 0.01% to 1% by weight of the total composition of an antioxidant.
Suitable antioxidants to be used herein include organic acids like citric acid, ascorbic acid, tartaric acid, adipic acid and sorbic acid, or amines like lecithin, or aminoacids like glutamine, methionine and cysteine, or esters like ascorbil palmitate, ascorbil stearate and triethylcitrate, or mixtures thereof. Preferred antioxidants for use herein are citric acid, ascorbic acid, ascorbil palmitate, lecithin or mixtures thereof.

Bleach activator

As an optional ingredient, the compositions of the present invention may comprise a bleach activator or mixtures thereof.
By "bleach activator", it is meant herein a compound which reacts with hydrogen peroxide to form a peracid. The peracid thus formed constitutes the activated bleach.
Suitable bleach activators to be used herein include those belonging to the class of esters, amides, imides, or anhydrides. Examples of suitable compounds of this type are disclosed in British Patent GB 1 586 769 and GB 2 143 231 and a method for their formation into a prilled form is described in European Published Patent Application EP-A-62 523. Suitable examples of such compounds to be used herein are tetracetyl ethylene diamine (TAED), sodium 3,5,5 trimethyl hexanoyloxybenzene sulphonate, diperoxy dodecanoic acid as described for instance in US 4 818 425 and nonylamide of peroxyadipic acid as described for instance in US 4 259 201 and n-nonanoyloxybenzenesulphonate (NOBS). Also suitable are N-acyl caprolactams selected from the group consisting of substituted or unsubstituted benzoyl caprolactam, octanoyl caprolactam, nonanoyl caprolactam, hexanoyl caprolactam, decanoyl caprolactam, undecenoyl caprolactam, formyl caprolactam, acetyl caprolactam, propanoyl caprolactam, butanoyl caprolactam pentanoyl caprolactam or mixtures thereof. A particular family of bleach activators of interest was disclosed in EP 624 154, and particularly preferred in that family is acetyl triethyl citrate (ATC). Acetyl triethyl citrate has the advantage that it is environmental-friendly as it eventually degrades into citric acid and alcohol. Furthermore, acetyl triethyl citrate has a good hydrolytical stability in the product upon storage and it is an efficient bleach activator. Finally, it provides good building capacity to the composition.
The compositions according to the present invention may comprise from 0.01% to 20%, preferably from 1% to 10%, and more preferably from 3% to 7% by weight of the total composition of said bleach activator.

Treating processes

In the present invention, the liquid aqueous composition of the present invention needs to be contacted with the surface to treat.
By "surfaces" it is meant herein any inanimate surface. These inanimate surfaces include, but are not limited to, hard-surfaces typically found in houses like kitchens, bathrooms, or in car interiors, e.g., tiles, walls, floors, chrome, glass, smooth vinyl, any plastic, plastified wood, table top, sinks, cooker tops, dishes, sanitary fittings such as sinks, showers, shower curtains, wash basins, WCs and the like, as well as fabrics including clothes, curtains, drapes, bed linens, bath linens, table cloths, sleeping bags, tents, upholstered furniture and the like, and carpets. Inanimate surfaces also include household appliances including, but not limited to, refrigerators, freezers, washing machines, automatic dryers, ovens, microwave ovens, dishwashers and so on.
Thus, the present invention also encompasses a process of treating a fabric, as the inanimate surface. In such a process a composition, as defined herein, is contacted with the fabrics to be treated. This can be done either in a so-called "pretreatment mode", where a composition, as defined herein, is applied neat onto said fabrics before the fabrics are rinsed, or washed then rinsed, or in a "soaking mode" where a composition, as defined herein, is first diluted in an aqueous bath and the fabrics are immersed and soaked in the bath, before they are rinsed, or in a "through the wash mode", where a composition, as defined herein, is added on top of a wash liquor formed by dissolution or dispersion of a typical laundry detergent. It is also essential in both cases, that the fabrics be rinsed after they have been contacted with said composition, before said composition has completely dried off.
By "treating" it is meant herein, cleaning, as the composition according to the present invention provides excellent stain removal performance on a broad range of stains and soils and on various surfaces due mainly to the presence of the surfactant system herein, as well as bleaching, as the composition according to the present invention provides excellent bleach performance due mainly to the presence of the peroxygen bleach and the surfactant system herein.
By "washing", it is to be understood herein that the fabrics are contacted with a conventional detergent composition comprising at least one surface active agent in an aqueous bath, this washing may occur by means of a washing machine or simply by hands.
By "in its neat form" it is to be understood that the liquid compositions are applied directly onto the fabrics to be pretreated without undergoing any dilution, i.e., the liquid compositions herein are applied onto the fabrics as described herein.
Indeed, it has been found that water evaporation contributes to increase the concentration of free radicals onto the surface of the fabrics and, consequently, the rate of chain reaction. It is also speculated that an auto-oxidation reaction occurs upon evaporation of water when the liquid compositions are left to dry onto the fabrics. Said reaction of auto-oxidation generates peroxy-radicals which may contribute to the degradation of cellulose. Thus, not leaving the liquid compositions, as described herein, to dry onto the fabric, in a process of pretreating soiled fabrics, contributes to reduce the tensile strength loss and/or color damage when pretreating fabrics with liquid peroxygen bleach-containing compositions.
In the pretreatment mode, the process comprises the steps of applying said liquid composition in its neat form onto said fabrics, or at least soiled portions thereof, and subsequently rinsing, or washing then rinsing said fabrics. In this mode, the neat compositions can optionally be left to act onto said fabrics for a period of time ranging from 1 min. to 1 hour, before the fabrics are rinsed, or washed then rinsed, provided that the composition is not left to dry onto said fabrics. For particularly though stains, it may be appropriate to further rub or brush said fabrics by means of a sponge or a brush, or by rubbing two pieces of fabrics against each other.
In another mode, generally referred to as "soaking", the process comprises the steps of diluting said liquid composition in its neat form in an aqueous bath so as to form a diluted composition. The dilution level of the liquid composition in an aqueous bath is typically up to 1:85, preferably up to 1:50 and more preferably 1:25 (composition:water). The fabrics are then contacted with the aqueous bath comprising the liquid composition, and the fabrics are finally rinsed, or washed then rinsed. Preferably in that embodiment, the fabrics are immersed in the aqueous bath comprising the liquid composition, and also preferably, the fabrics are left to soak therein for a period of time ranging from 1 minute to 48 hours, preferably from 1 hour to 24 hours.
In yet another mode which can be considered as a sub-embodiment of "soaking", generally referred to as "bleaching through the wash", the liquid composition is used as a so-called laundry additive. And in that embodiment the aqueous bath is formed by dissolving or dispersing a conventional laundry detergent in water. The liquid composition in its neat form is contacted with the aqueous bath, and the fabrics are then contacted with the aqueous bath containing the liquid composition. Finally, the fabrics are rinsed.
In another embodiment the present invention also encompasses a process of treating a hard-surface, as the inanimate surface. In such a process a composition, as defined herein, is contacted with the hard-surfaces to be treated. Thus, the present invention also encompasses a process of treating a hard-surface with a composition, as defined herein, wherein said process comprises the step of applying said composition to said hard-surface, preferably only soiled portions thereof, and optionally rinsing said hard-surface.
In the process of treating hard-surfaces according to the present invention the composition, as defined herein, may be applied to the surface to be treated in its neat form or in its diluted form typically up to 200 times their weight of water, preferably into 80 to 2 times their weight of water, and more preferably 60 to 2 times.
When used as hard surfaces cleaners the compositions of the present invention are easy to rinse and provide good shine characteristics on the treated surfaces.
Depending on the end-use envisioned, the compositions herein can be packaged in a variety of containers including conventional bottles, bottles equipped with roll-on, sponge, brusher or sprayers.
The invention is further illustrated by the following examples.

Examples

Following compositions were made by mixing the listed ingredients in the listed proportions (weight % unless otherwise specified).

Compositions	I.	II.	III.	IV.	V.	VI.	VII.	VIII.	IX.	X.	XI.
Hostapur SAS®	-	1.0	1.0	2.0	2.0	6.0	12.0	-	-	-	-
Nansa® SSA	-	-	-	-	-	-	-	1.0	1.0	2.0	2.0
Empigen® BBL	2.0	-	-	-	-	-	-	-	-	-	-
Dobanol® 23-3	1.0	6.0	-	6.0	-	-	-	6.0	-	6.0	-
Dobanol® 23-6.5	-	-	-	-	-	12.0	12.0	-	-	-	-
Dobanol® 45-7	3.0	-	6.0	-	6.0	-	-	-	6.0	-	6.0
H₂O₂	7.0	7.0	7.0	7.0	7.0	6.0	6.0	7.0	7.0	7.0	7.0
Water and minors	up to 100%
All examples have a pH under 7 Hostapur® SAS is a C14-C17 paraffin sulphonate (sodium salt) commercially available from Hoechst. Nansa® SSA is a C12 alkyl benzene sulphonate available from Albright & Wilson. Empigen® BBL is a lauryl betaine available from Albright & Wilson. Dobanol® 23-3 is a C12-C13 EO3 nonionic surfactant commercially available from SHELL. Dobanol® 23-6.5 is a C12-C13 EO6.5 nonionic surfactant commercially available from SHELL. Dobanol® 45-7 is a C14-C15 EO7 nonionic surfactant commercially available from SHELL.

All the above compositions show good stain removal and bleaching performance.

Claims

A liquid composition having a pH of below 7 and comprising a peroxygen bleach or a mixture thereof, a sulphonated anionic surfactant and a second surfactant wherein the weight ratio of the sulphonated anionic surfactant to the second surfactant is less than or equal to one.
A composition according to claim 1 wherein said peroxygen bleach is selected from the group consisting of : hydrogen peroxide; water soluble sources of hydrogen peroxide; organic or inorganic peracids; hydroperoxides; and diacyl peroxides; and mixtures thereof.
A composition according to any of the preceding claims wherein said peroxygen bleach is selected from the group consisting of hydrogen peroxide and diacyl peroxides and mixtures thereof.
A composition according to any of the preceding claims wherein said composition comprises from 0.01% to 20% by weight of the total composition of said peroxygen bleach or a mixture thereof.
A composition according to any of the preceding claims wherein said sulphonated anionic surfactant is selected from the group consisting of : alkyl sulphonates; alkyl aryl sulphonates; alkyl alkoxylated sulphonates; C₆-C₂₀ alkyl alkoxylated linear or branched diphenyl oxide disulphonates; naphthalene sulphonates; and mixtures thereof.
A composition according to any of the preceding claims wherein said composition comprises from 0.01% to 25% by weight of the total composition of a sulphonated anionic surfactant.
A composition according to any of the preceding claims wherein said second surfactant is a surfactant selected from the group consisting of nonionic surfactants, amphoteric surfactants, zwitterionic surfactants and mixtures thereof.
A composition according to any of the preceding claims wherein said second surfactant is a nonionic surfactant.
A composition according to any of the preceding claims wherein said composition comprises from 0.01% to 25% by weight of the total composition of a second surfactant.
A process of treating fabrics which includes the steps of diluting in an aqueous bath a composition according to any of the preceding claims, in its neat form, contacting said fabrics with said aqueous bath comprising said liquid composition, and subsequently rinsing, or washing then rinsing said fabrics.
A process according to claim 10, wherein the fabrics are left to soak in said aqueous bath comprising said liquid composition for a period of time ranging from 1 minute to 48 hours.
A process according to any of the claims 10 to 11, wherein said aqueous bath is formed by dissolving or dispersing a conventional laundry detergent in water.
A process of pretreating fabrics which comprises the steps of applying a liquid composition according to any of the claims 1 to 9, in its neat form, onto said fabrics, before rinsing said fabrics, or washing then rinsing said fabrics.
A process of treating a hard-surface with a composition according to any of the claims 1 to 9, wherein said process comprises the step of applying said composition to said hard-surface and optionally rinsing said hard-surface.
The use of a sulphonated anionic surfactant in a liquid composition having a pH below 7 to treat fabrics whereby said compositions provide stain removal benefits.