WO1996006154A1

WO1996006154A1 - Detergent bleach composition

Info

Publication number: WO1996006154A1
Application number: PCT/EP1995/002708
Authority: WO
Inventors: Ronald Hage; Lambertus Bernardus Krijnen
Original assignee: Unilever N.V.; Unilever Plc
Priority date: 1994-08-19
Filing date: 1995-07-10
Publication date: 1996-02-29
Also published as: ZA955974B; AU3077495A

Abstract

In a fabric washing process, the resulting colour-fading of coloured fabric (particularly coloured cotton fabric) is reduced while maintaining a favourable bleaching performance by using a detergent bleach composition comprising a surface-active material, a peroxy bleaching agent and a specific type of a dinuclear manganese complex as effective bleach catalyst. A particularly preferred dinuclear manganese complex is: [(Et-bridged(Me2TACN)2)MnIIIMnIV(ν-0)¿2?(ν-OAc)]?2+(PF¿6-)2.

Description

Detergent Bleach Composition

Field of the invention

This invention relates to detergent bleach compositions. More particularly, it relates to improved detergent bleach compositions, especially but not exclusively adapted for washing and cleaning of fabric, containing a surfactant material, a peroxygen bleaching agent and a bleach catalyst.

Background of the invention

A variety of manganese complexes has been proposed as catalysts for enhancing the activity of peroxygen bleaches such as hydrogen peroxide, hydrogen peroxide liberating or generating compounds and inorganic and organic peroxyacids. They include manganese-gluconate complexes as described in EP-A-237,111 and manganese polyol complexes as described in EP-A-443,651.

However, the performance of these Mn-based catalysts is inadequate when used for bleaching in the low temperature region of about 20-40°C, and detergent bleach compositions comprising these Mn-based catalysts are not effective in removing a wide range of stains.

In several patent documents, for instance EP-A-458,397 and EP-A-458,398, novel triazacyclononane-based manganese complexes are disclosed, which display a very high oxidation catalytic activity at low temperatures, and which are, therefore, particularly suitable as bleach catalysts. A major improvement of the bleaching activity is obtained by the fact that these compounds are stable under washing conditions e.g. oxidising environment (as a result of the presence of hydrogen peroxide or peroxyacids) . However, we found that detergent compositions including these compounds may give rise to colour fading of coloured cotton containing fabric particularly when applied at increased washing temperatures.

In EP-A-544,490, a specific group of manganese complexes is disclosed which comprise two ligand of formula

rC NR³ - (CR¹(R²)u⁾t rs""l

wherein t is an integer from 2 to 3; s is an integer from 3 to 4; u is zero or one;

R¹ and R² are each independently selected from H, alkyl, aryl, both optionally substituted; and

R³ is independently selected from hydrogen, alkyl, aryl both optionally substituted, with the proviso that a bridging unit R⁴ is formed by one R³ unit from each ligand where R⁴ is the group C_nR⁵R⁶-(D) -C_mR⁵R⁶ where p is zero or one;

D is selected from a heteroatom such as oxygen and NR⁷ or is part of an aromatic or saturated homonuclear or heteronuclear ring; n is an integer from 1 to 4; m is an integer from 1 to 4; with the proviso that n + m <= 4 if p is zero or p is one and D is part of an aromatic or saturated homonuclear or heteronuclear ring; and that n + m <= if p is one and D is a heteroatom such as oxygen or NR⁷; R⁵ and R⁶ are each independently selected from H, NR⁸ and OR⁹, alkyl, aryl, optionally substituted and R⁷, R⁸ and R⁹ are each independently selected from H, alkyl, aryl, both optionally substituted.

We have now surprisingly found that the use of detergent bleach compositions containing the above-identified specific group of manganese complexes disclosed by EP-A- 544,490, result in significantly reduced colour fading of coloured cotton containing fabric as compared to compositions containing the manganese complexes disclosed by EP-A-458,397 and EP-A -458,398, when applied for washing said fabric.

Definition of the invention

The present invention relates to the use of a detergent bleach composition comprising a surface active material, a peroxy bleaching agent and a bleach catalyst, for washing coloured fabric at normal washing temperatures, characterised in that said bleach catalyst is a dinuclear manganese complex having the formula:

wherein Mn is manganese which can individually be in the III or IV oxidation state; X₂, X₂ and X₃ each independently represent a coordinating or bridging species selected from the group consisting of H₂0, 0₂ ^2~, 0^2", OH^", H0₂ ^", SH^~, S^2", >S0, Cl^", N^3", SCN^", RCOO^", RSO^" ₃, NH₂ ^", RB0₂ ^2" and NR₃, with R being H, alkyl, aryl, both optionally substituted, R'COO^" where R¹ is alkyl, aryl, both optionally substituted; L is a ligand which is an organic molecule containing at least three nitrogen atoms which coordinates via all or some of the nitrogen atoms to the manganese centres; z denotes the charge of the complex and is an integer which can be positive or negative;

Y is a monovalent or multivalent counter-ion, leading to charge neutrality, which is dependent upon the charge z of the complex; and q = z/[charge Y] whereby the bleach catalyst comprises two ligands L having the formula:

wherein t is an integer from 2 to 3; s is an integer from 3 to 4;

R³ is independently selected from hydrogen, alkyl, aryl both optionally substituted, with the proviso that a bridging unit R⁴ is formed by one R³ unit from each ligand where R⁴ is the group C_nR⁵R⁶-(D)_-C_mR⁵R⁶ where p is zero or one;

D is selected from a heteroatom or a heteroatom containing group, such as oxygen and NR⁷, or is part of an aromatic or saturated homonuclear or heteronuclear ring; n is an integer from 1 to 4; m is an integer from 1 to 4; with the proviso that n + m < 4;

R⁵ and R⁶ are each independently selected from H, NR⁸ and OR⁹, alkyl, aryl, optionally substituted and R⁷, R⁸ and R⁹ are each independently selected from H, alkyl, aryl, both optionally substituted.

The present invention also provides a process of washing coloured fabric at normal washing temperatures, whereby a detergent bleach composition according to the invention is used.

Detailed description

The above mentioned reduced colour fading occurred at a wide range of temperatures ranging from about 20° C to as 96/06154

high as 90°C but was particularly noticeable at temperatures between 40°C and 70°C.

A remarkably reduced colour fading was noticed when the detergent bleach composition of the invention was used for washing coloured cotton containing fabric.

If cotton cloth coloured with red an black dyes (eg: Acid Red 120 and Reactive Black 5) were washed with the detergent bleach composition of the invention, a remarkable reduction of colour fading of said cloth was found. After said dyed cotton cloth were washed 5 times during 15 minutes at a temperature of 60°C and an initial pH of 10 and rinsed in between said 5 washing cycles, a more than 50% reduction in colour fading was observed as compared to the colour fading resulting from treating said cotton cloth with a detergent bleach composition containing one of the manganese complexes disclosed by EP-A-458,397 and EP-A - 458,398.

The bleach catalyst The manganese complexes which may be included in the detergent bleach composition of the present invention, are reported in EP-A-544,490, as unusually effective bleach and oxidation catalysts. In the further description of the invention they will also be referred to as the "bleach catalyst" or simply "catalyst".

Examples of suitable ligands in their simplest form which may be present in the bleach catalysts are:

(i) 1,4,7-triazacyclononane;

1,4,7-triazacyclodecane;

1,4,8-triazacycloundecane;

1,5,9-triazacyclododecane.

1,4,7-trimethyl-1,4,7-triazacyclononane. 1,4,7-trimethyl-1,4,7-triacyclodecane;

1,4,8-trimethyl-1,4,8-triazacycloundecane; 1,5,9-trimethyl-1,5,9-triazacyclododecane. (ii) Tris(pyridin-2-yl)methane;

Tris(pyrazol-1-yl)methane;

Tris(imidazol-2-y1)methane; Tris(Triazol-l-yl)methane,

(iii) Tris(pyridin-2-yl)borate;

Tris(triazol-1-yl)borate;

Tris(pyrazol-l-yl)borate;

Tris(imidazol-2-yl)phosphine;

Tris(imidazol-2-y1)borate. (iv) 1,3,5-trisamino-cyclohexane;

1,1,l-tris(methylamino)ethane.

(v) Bis(pyridin-2-yl-methyl)amine; Bis(pyrazol-1-yl-methyl)amine;

Bis(triazol-1-yl-methyl)amine;

Bis(imidazol-2-yl-methyl)amine,

These ligands which may be optionally substituted on the amine N-atom and/or the CH₂ carbon atom and/or the aromatic ring, are all connected to another ligand by a bridging unit as mentioned in the definition of the invention. Bleach catalysts containing thus connected ligands with different chemical structure, are within the scope of the invention

Of these, the following ligand is especially preferred: 1,2-bis(4,7-dimethyl-l,4,7-triaza-l-cyclonoyl) ethane (Et-bridged(Me₂TACN)₂) .

The type of counter-ion Y for charge neutrality is not critical for the activity of the complex and can be selected from for example any of the following counter- ions: chloride; sulphate; nitrate; methylsulphate; surfactant-anions, such as the long-chain alkylsulphates, alkylsulphonates, alkylbenzenesulphonates, tosylate; trifluormethylsulphonate; perchlorate (C10₄ ^~) , BPh₄ ^" and PF₆" , though some counter-ions are more preferred than others for reasons of product property and safety.

The most preferred manganese complex as used in the present invention is:

[ (Et-bridged(Me₂TACN)₂)Mn^XIIMn^IV(μ-0)₂ (μ-OAc) ]²⁺(PF₆ ^")₂.

The peroxy bleaching agent

The peroxy bleaching agents may be compounds which are capable of yielding hydrogen peroxide in aqueous solution. Hydrogen peroxide sources are well known in the art. They include the alkali metal peroxides, organic peroxides such as urea peroxide, and inorganic persalts, such as the alkali metal perborates, percarbonates, perphosphates, persilicates and persulphates. Mixtures of two or more such compounds may also be suitable.

Particularly preferred are sodium perborate tetrahydrate and, especially, sodium perborate monohydrate. Sodium perborate monohydrate is preferred because of its high active oxygen content. Sodium percarbonate may also be preferred for environmental reasons. The amount thereof in the composition of the invention usually will be within the range of about 5-35 % by weight, preferably from 10-25 % by weight.

Alkylhydroxy peroxides are another class of peroxy bleaching agents. Examples of these materials include cumene hydroperoxide and t-butyl hydroperoxide.

Organic peroxyacids may also be suitable as the peroxy bleaching agent. Such materials normally have the general formula:

0 // HO0 C R Y wherein R is an alkylene or substituted alkylene group containing from 1 to about 20 carbon atoms, optionally having an internal amide linkage; or a phenylene or substituted phenylene group; and Y is hydrogen, halogen, alkyl, aryl, an imido-aromatic or non-aromatic group, a C00H or

C 00H

group or a quaternary ammonium group.

Typical monoperoxy acids useful herein include, for example:

(i) peroxybenzoic acid and ring-substituted peroxybenzoic acids, e.g. peroxy-α-naphthoic acid; (ii) aliphatic, substituted aliphatic and arylalkyl monoperoxyacids, e.g. peroxylauric acid, peroxystearic acid and N,N-phthaloylaminoperoxy caproic acid (PAP) ; and

(iii) 6-octylamino-6-oxo-peroxyhexanoic acid.

Typical diperoxyacids useful herein include, for example:

(iv) 1,12-diperoxydodecanedioic acid (DPDA) ;

(v) 1,9-diperoxyazelaic acid;

(vi) diperoxybrassilic acid; diperoxysebasic acid and diperoxyisophthalic acid;

(vii) 2-decyldiperoxybutane-l,4-diotic acid; and (viii) 4,4'-sulphonylbisperoxybenzoic acid.

Also inorganic peroxyacid compounds are suitable, such as for example potassium monopersulphate (MPS) . If organic or inorganic peroxyacids are used as the peroxygen compound, the amount thereof will normally be within the range of about 2-10 % by weight, preferably from 4-8 % by weight. All these peroxide compounds may be utilized alone or in conjunction with a peroxyacid bleach precursor and/or an organic bleach catalyst not containing a transition metal.

Peroxyacid bleach precursors are known and amply described in literature, such as in the British Patents 836988; 864,798; 907,356; 1,003,310 and 1,519,351; German Patent 3,337,921; EP-A-0185522; EP-A-0174132; EP-A-0120591; and US Patents 1,246,339; 3,332,882; 4,128,494; 4,412,934 and 4,675,393.

Another useful class of peroxyacid bleach precursors is that of the cationic i.e. quaternary ammonium substituted peroxyacid precursors as disclosed in US Patent 4,751,015 and 4,397,757, in EP-A0284292 and EP-A-331,229. Examples of peroxyacid bleach precursors of this class are: 2-(N,N,N-trimethyl ammonium) ethyl sodium-4-sulphonphenyl carbonate chloride - (SPCC) ; N-octyl,N,N-dimehyl-N₁₀-carbophenoxy decyl ammonium chloride - (ODC) ;

3-(N,N,N-trimethyl ammonium) propyl sodium-4-sulphophenyl carboxylate; and N,N,N-trimethyl ammonium toluyloxy benzene sulphonate.

A further special class of bleach precursors is formed by the cationic nitriles as disclosed in EP-A-303,520 and in European Patent Specification No. 's 458,396 and 464,880.

Any one of these peroxyacid bleach precursors can be used in the present invention, though some may be more preferred than others.

Of the above classes of bleach precursors, the preferred classes are the esters, including acyl phenol sulphonates and acyl alkyl phenol sulphonates; the acyl-amides; and the quaternary ammonium substituted peroxyacid precursors including the cationic nitriles.

Examples of said preferred peroxyacid bleach precursors or activators are sodium-4-benzoyloxy benzene sulphonate (SBOBS); N,N,N'N'-tetraacetyl ethylene diamine (TAED) ; sodium-l-methyl-2-benzoyloxy benzene-4-sulphonate; sodium- 4-methyl-3-benzoloxy benzoate; SPCC; trimethyl ammonium toluyloxy-benzene sulphonate; sodium nonanoyloxybenzene sulphonate (SNOBS); sodium 3,5,5-trimethyl hexanoyloxybenzene sulphonate (STHOBS) ; and the substituted cationic nitriles.

The precursors may be used in an amount of up to 12 % , preferably from 2-10 % by weight, of the composition.

Organic bleach catalyst most suitable for being utilized here are the so-called sulphonimides as disclosed in EP-A- 0453003 and EP-A-0446982.

The surface-active material

The detergent bleach compositions used according to the invention generally contain surface-active material in an amount of from 10 to 50% by weight. Said surface-active material may be naturally derived, such as soap, or a synthetic material selected from anionic, nonionic, amphoteric, zwitterionic, cationic actives and mixtures thereof. Many suitable actives are commercially available and are fully described in the literature, for example in "Surface Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch.

Typical synthetic anionic surface-actives are usually water-soluble alkali metal salts of organic sulphates and sulphonates having alkyl radicals containing from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl portion of higher aryl radicals. Examples of suitable synthetic anionic detergent compounds are sodium and ammonium alkyl sulphates, especially those obtained by sulphating higher (C₈-C₁₈) alcohols produced, for example, from tallow or coconut oil; sodium and ammonium alkyl (C₉-C₁₀) benzene sulphonates, particularly sodium linear secondary alkyl (C₁₀-C₁₅) benzene sulphonates; sodium alkyl glyceryl ether sulphates, especially those ester of the higher alcohols derived from tallow or coconut oil fatty acid monoglyceride sulphates and sulphonates; sodium and ammonium salts of sulphuric acid esters of higher (C₈-C₁₈) fatty alcohol alkylene oxide, particularly ethylene oxide, reaction products; the reaction products of fatty acids such as coconut fatty acids esterified with isethionic acid and neutralised with sodium hydroxide; sodium and ammonium salts of fatty acid amides of methyl taurine; alkane monosulphonates such as those derived by racting alpha-olefins (C₈-C₂₀) with sodium bisulphite and those derived by reaction paraffins with S0₂ and C₁₂ and then hydrolysing with a base to produce a random sulphonate; sodium an ammonium C₇-C₁₂ dialkyl sulphosccinates; and olefin sulphonates which term is used to describe material made by reacting olefins, particularly C₁₀-C₂₀ alpha-olefins, with S0₃ and then neutralising and hydroysing the reaction product. The preferred anionic detergent compounds are sodium (C₁₀-C₁₅) alkylbenzene sulphonates, sodium C₁₆-C₁₈) alkyl ether sulphates.

Examples of suitable nonionic surface-active compounds which may be used, preferably together with the anionic surface-active compounds, include, in particular, the reaction products of alkylene oxides, usually ethylene oxide, with alkyl (C₆-C₂₂) phenols, generally 5-25 EO, i.e. 5-25 units of ethylene oxides per molecule; and the condensation products of aliphatic (C₈-C₁₈) primary or secondary linear or branched alcohols with ethylene oxide, generally 2-30 EO. Other so-called nonionic surface- actives include alkyl polyglycosides, sugar ester, long- chain tertiary amine oxides, long-chain tertiary phosphine oxides and dialkyl sulphoxides.

Amphoteric or zwitterionic surface-active compounds can also be used in the compositions of the invention but this is not normally desired owing to their relatively high cost. If any amphoteric or zwitterionic detergent compounds are used, it is generally in small amounts in compositions based on the much more commonly used synthetic anionic and nonionic actives.

As disclosed by EP-A-544,490, the performance of the hereinbefore described bleach catalyst, may be dependent upon the active detergent system and the builder system present in the detergent bleach composition of the invention.

The detergent bleach composition of the invention will preferably comprise from 1-15 % wt of anionic surfactant and from 10-40 % by weight of nonionic surfactant. In a further preferred embodiment the detergent active system is free from C₁₆-C₁₂ fatty acids soaps.

The detergencv builder

The composition of the invention normally and preferably also contains a detergency builder in an amount of from about 5-80 % by weight, preferably from about 10-60 % by weight.

Builder materials may be selected from 1) calcium sequestrant materials, 2) precipitating materials, 3) calcium ion-exchange materials and 4) mixtures thereof.

Examples of calcium sequestrant builder materials include alkali metal polyphosphates, such as sodium tripolyphosphate; nitrilotriacetic acid and its water- soluble salts; the alkali metal salts of carboxymethyloxy succinic acid, ethylene diamine tetraacetic acid, oxydisuccinic acid, mellitic acid, benzene polycarboxylic acids, citric acid; and polyacetal carboxylates as disclosed in US Patents 4,144,226 and 4,146,495.

Examples of precipitating builder materials include sodium orthophosphate and sodium carbonate.

Examples of calcium ion-exchange builder materials include the various types of water-insoluble crystalline or amorphous aluminosilicates, of which zeolites are the best known representatives, e.g. zeolite A, zeolite B (also know as Zeolite P) , zeolite C, zeolite X, zeolite Y and also the zeolite P type as described in EP-A-0384070.

In particular, the compositions of the invention may contain any one of the organic and inorganic builder materials, though, for environmental reasons, phosphate builders are preferably omitted or only used in very small amounts.

Typical builders usable in the present invention are, for example, sodium carbonate, calcite/carbonate, the sodium salt of nitrilotriacetic acid, sodium citrate, carboxymethyloxy malonate, carboxymethyloxy succinate and the water-insoluble crystalline or amorphous alu inosilicate builder material, each of which can be used as the main builder, either alone or in admixture with minor amounts of other builders or polymers as co-builder.

It is preferred that the composition contains not more than 5% by weight of a carbonate builder, expressed as sodium carbonate, more preferable not more than 2.5 % by weight to substantially nil, if the composition pH lies in the lower alkaline region of up to 10. Other ingredients

Apart form the components already mentioned, the detergent bleach compositions of the invention can contain any of the conventional additives in amounts of which such materials are normally employed in fabric washing detergent compositions. Examples of these additives include buffers such as carbonates, lather boosters, such as alkanolamides, particularly the monoethanol amides derived from palmkernel fatty acids and coconut fatty acids; lather depressants, such as alkyl phosphates and silicones; anti-redeposition agents, such as sodium carboxy ethyl cellulose and alkyl or substituted alkyl cellulose ethers; stabilizers, such as phosphonic acid derivatives (i.e. Dequest® types); fabric softening agents; inorganic salts and alkaline buffering agents, such as sodium sulphate, sodium silicate etc.; and usually in very small amounts, fluorescent agents; perfumes; enzymes, such as proteases, cellulases, lipases, amylases and oxidases; germicides and colourants.

When using a hydrogenperoxide source, such as sodium perborate or sodium percarbonate, as the bleaching agent, it is preferred that the composition contains not more than 5 % by weight of a carbonate buffer, expressed as sodium carbonate, more preferable not more than 2.5% by weight to substantially nil, if the composition pH lies in the lower alkaline region of up to 10.

Of the additives, transition metal sequestrants, such as EDTA and the phosphonic acid derivatives, e.g. ethylene diamine tetra-(methylene phosphonate)-EDTMP- are of special importance, as not only do they improve the stability of the catalyst/H₂0₂ system and sensitive ingredients, such as enzymes, fluorescent agents, perfumes and the like, but also improve the bleach performance, especially at the higher pH region of above 10, particularly at pH 10.5 and above. Accordingly detergent bleach compositions comprising a surface-active material, a peroxide bleaching agent, the manganese complex bleach catalyst, a carbonate builder and a transition metal sequestrant, having pH in solution of above 10, especially of 10.5 and above, are within the purview of the present invention.

Another optional but highly desirable additive ingredient with multi-functional characteristics in detergent compositions is from 0.1 % to about 3 % by weight of a polymeric material having a molecular weight of from 1,000 to 2,000,000 and which can be a homo- or co-polymer of acrylic acid, maleic acid, or salt or anhydride thereof, vinyl pyrrolidone, methyl- or ethylvinyl ethers, and other polymerizable vinyl monomers. Preferred examples of such polymeric materials are polyacrylic acid or plyacrylate; polymaleic acid/acrylic acid copolymer; 70-30 acrylic acid/hydroxyethyl maleate copolymer; 1:1 styrene/maleic acid copolymer; isobutylene/maleic acid and diisobutylene/maleic acid copolymers; methyl- and ethylvinylether/maleic acid copolymers; ethylene/maleic acid copolymer; polyvinyl pyrrolidone; and vinyl pyrrolidone/maleic acid copolymer.

The detergent bleach composition of the invention can be formulated in any suitable form, such as the powdered or granulated, the liquid or paste-like form.

When formulated as free-flowing particles, e.g. in powdered or granulated form, the detergent bleach composition can be produced by any of the conventional techniques employed in the manufacture of detergent compositions, for instance by slurry-making, followed by spray-drying to form a detergent base powder to which the heat-sensitive ingredients including the peroxide compound bleach and optionally some other ingredients as desired, and the bleach catalyst, can be added as dry substances. It will be appreciated, however, that the detergent base powder compositions, to which the bleach catalyst is added, can itself be made in a variety of their ways, such as the so-called part-part processing, non-tower route processing, dry-mixing, agglomeration, granulation, extrusion, compacting and densifiying processes etc. , such ways being well known to those skilled in the art and not forming the essential part of the present invention.

Experimental method

Bleach experiments were carried out in glass vessels, equipped with a temperature controlled heating spiral in quartz, magnetic stirrer, thermo-couple and pH-electrode.

The experiments were carried out at an isothermal temperature of 60°C, whereby tapwater (16°FH) was used at a pH of 10. Furthermore, a dosage of approximately 5 g/1 of the bleaching detergent formulation to be tested was applied for each experiment. The test formulations had the following general composition:

component parts by weight base composition 62.11 sodium carbonate 2.00 sodium percarbonate 20.5

TAED 9.25

Manganese complex catalyst 0.008

Dequest 2047 0.45

Minors, including fluorescer, anti-foaming agent,water 3.50

2 cotton test cloth containing Reactive Black 5 dye were washed for 15 minutes in 1 liter of tap water at 60°C and containing 5 g/1 of the detergent formulation to be tested. At the start of the test the pH was adjusted to 10.0. After 15 minutes, the cloth were removed from the solution. rinsed with tap water for 10 minutes. This procedure of washing and rinsing was repeated 5 times.

Subsequently, the washed test cloth were subjected to a colour measurement by using a HunterLab Spectrocolorimeter. The measured colour difference (ΔE) between the washed and non-washed cloth is defined as follows: ΔE = [(ΔL)² + (Δa)² + (Δb)² ]**, wherein: ΔL is a measure for the difference in darkness between the washed and unwashed test cloth;

Δa and Δb are measures for the difference in redness respectively yellowness between both cloth.

With regard to this colour measurement technique, reference is made to Commission International de l'Eclairage (CIE); Recommendation on Uniform Colour Spaces, color difference equations, psychometric color terms, Supplement no 2 to CIE Publication, No 15, Colormetry, Bureau Central de la CIE, Paris, 1978.

The invention will now be illustrated by way of the following non-limiting examples.

Preparation Examples

Synthesis of l,2-bis(4,7-dimethyl-l,4,7-triaza-l-cyclonoyl) ethane (Et-bridged(Me₂TACN)₂) .

99.4 g distilled 1,4,7-triazacyclononane ((T.J. Atkins, et al, Org. Synth., 58, 86 (1978)) was warmed to 65 °C (without solvent) and 91.7g of N,N-dimethylformamide dimethyl acetal was added dropwise as fast as possible while stirring between 60 and 70 °C. The mixture was refluxed for 16 h, cooled and the low-boiling products were evaporated. The resulting tricyclo[5.2.1.0 ^,10]-1,4,7- trazadecane (1) was purified by destination under vacuum (bp 77 °C/1 mm) . 1,2-dibromoethane (3.25 g) was added to (1) (6.0 g) in 30 ml acetonitrile and the mixture was kept at room temperature for 4 days. The precipitate obtained was filtered, washed with acetonitrile and ether and dried to leave 7.65 g of white microcrystalline salt (which is: 1,2- bis(tricyclo[5.2.1.0⁴'¹⁰]-1,4,7-trazadecanyl)ethane dibromide (2) ) .

7.0 g of compound 2 was dissolved in 21 g of formic acid and 14 g of 37% formaldehyde was added. The mixture was heated at 95 °C for 24 h , then cooled and evaporated. Water was added and the solution was again evaporated. The remaining oil was dissolved in 100 ml water and the impurities were extracted by washing with ether. The water layer was made pH>12 by addition of 40% NaOH solution and then 5 times extracted with hexane. Drying and evaporation of ether, yielded 5.0 g of an almost colourless oil, which was further purified by vacuum destination (bp 195 °C/1 mm) (3) . Synthesis of Mn complex: [ (Et-bridged(Me₂TACN)-OM^^Mn^Cμ- O^Cμ-OAc)]²⁺(PF₆ ^")₂.

2.5 gr of ligand (3) was dissolved in 100 ml ethanol/water (2/1 v/v) and 3.7 g of Mn(OAc)₂.4H₂0 and 4.14 g of KPF₆ were added. The mixture was stirred for 20 minutes at 40- 55°C, and subsequentyl cooled (ice bath) whilst stirring. After 10 minutes a freshly permixed solution containing 1 ml, 1M of H 0₂ and 1 ml of 1.5 M NaOH was added dropwise during 3-5 minutes. After stirring for another 10-15 minutes at 0°C, the mixture was neutralised with 2 M H₃CC00H to pH 7, the celite was added and the mixture was filtered over a bed of celite. The combined filtrates were evaporated (vacuum, 40°C) and the product was dissolved in acetonitrile to remive salts and again filtered. The filtrate was partially evaporated (vacuum , 40°C) , water was added and filtered. The solid was washed with ethanol and hexane and dried. Further purification took place by dissolving 4.0 g of the green powder in 30 ml of acetonitrile and allowing ether to diffuse in the solution at 5 °C. Green-black crystals (3.8 g) were isolated.

Example 1. Comparative Example A Two detergent products having the general composition shown above and including different types of manganese complex catalyst were tested using the above described experimental method.

The tested products included the following base composition: Component parts by weight

Na-PAS 1) 5.52

Nonionic 7E0 2) 7.65 Nonionic 3EO 3) 5.02

Soap 1.95 zeolite A24 (anhydrous) 34.80 light soda ash 1.06

Moisture, salts, NDOM, minors 6.10

wherein:

1) Na-PAS : C₁₂ sodium salt of primary alkyl sulphate;

2) Nonionic 7E0 : C₁₂-C₁₄ ethoxylated alcohol having on average 7 ethylene oxide groups (e.g.

Synperonic A7, ex ICI) ;

3) Nonionic 3EO : C₁₂-C₁₄ ethoxylated alcohol having on average 3 ethylene oxide groups (e.g.

Synperonic A3, ex ICI).

The following manganese complex catalysts were present in the products to be tested:

Example Mn complex catalyst no type

A [Mn^IV ₂(μ-0)₃(Me₃TACN)₂] (PF₆ ^")₂. H₂0

1 [ (Et-bridged(Me₂TACN)₂)Mn^ι:rIMn^IV(μ-0)₂(μ-OAc) ]²⁺(PF₆ ^")₂

The following results were obtained, showing ΔE-values found with respect to the cotton cloth containing Reactive Black 5.

Colour fading (ΔE) Example A 18.8 Example 1 8.5 It is noted that a higher ΔE-value indicates a higher degree of colour fading. It can therefore be noticed that using the above-mentioned technique the colour fading observed as a result of treatment with the product according to the present invention (see Example 1) is less than 50% of the colour fading found after treating the test cloth with the detergent product of Example A.

Claims

1. Use of a detergent bleach composition comprising a surface active material, a peroxy bleaching agent and a bleach catalyst, for washing coloured fabric at normal washing temperatures, characterised in that said bleach catalyst is a dinuclear manganese complex having the formula:

wherein Mn is manganese which can individually be in the III or IV oxidation state; X-_, X₂ and X₃ each independently represent a coordinating or bridging species selected from the group consisting of H₂0, 0₂ 2- OH^" , H0_; SH^" .2-

>S0 , Cl^" , N^J~ , SCN^" , RCOO^" , RS0^~ ₃ , NH₂ ^" , B0^ 2-~ and NR₃ , with

R being H, alkyl, aryl, both optionally substituted, R'COO^" where R¹ is alkyl, aryl, both optionally substituted;

L is a ligand which is an organic molecule containing at least three nitrogen atoms which coordinates via all or some of the nitrogen atoms to the manganese centres; z denotes the charge of the complex and is an integer which can be positive or negative;

Y is a monovalent or multivalent counter-ion, leading to charge neutrality, which is dependent upon the charge z of the complex; and q = z/[charge Y]

whereby the bleach catalyst comprises two ligands L having the formula:

|—[NR³ - (CR^n - wherein t is an integer from 2 to 3; s is an integer from 3 to 4;

R¹ and R² are each independently selected from H, alkyl, aryl, both optionally substituted; and R³ is independently selected from hydrogen, alkyl, aryl both optionally substituted, with the proviso that a bridging unit R⁴ is formed by one R³ unit from each ligand where R⁴ is the group C_nR⁵R⁶-(D)_p-C_mR⁵R⁶ where p is zero or one; D is selected from a heteroatom or a heteroatom containing group, such as oxygen and NR⁷, or is part of an aromatic or saturated homonuclear or heteronuclear ring; n is an integer from 1 to 4; m is an integer from 1 to 4; with the proviso that n + m < 4;

R⁵ and R⁶ are each independently selected from H, NR⁸ and

OR⁹, alkyl, aryl, optionally substituted and R⁷, R⁸ and R⁹ are each independently selected from H, alkyl, aryl, both optionally substituted.

2. Use according to claim 1, for washing coloured cotton containing fabric.

3. Use according to claim 1 or 2, wherein cotton fabric is washed at temperatures between 40°C and 70°C.

4. Use according to any of claims 1-3, wherein the detergent composition contains, as a bleach catalyst:

[ (Et-bridged(Me₂TACN)₂)Mn^ι:[IMn^IV(μ-0)₂(μ-OAc) ]²⁺(PF₆ ^")₂

5. Use according to any of claims 1-4, wherein the bleaching agent present in the detergent bleach composition is a hydrogen peroxide source.

6. Use of according to claim 5, wherein the detergent bleach composition has a pH of up 10 and contains not more than 5 % by weight of a carbonate, expressed as sodium carbonate.

7. Use according to any of claims 1-4, wherein the bleaching agent is a peroxyacid compound.

8. Process of washing coloured fabric at normal washing temperatures, whereby the detergent composition according to claim 1 is applied.

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