EP0934395A1 - Detergent compositions - Google Patents

Abstract

There is provided a process for preparing a detergent composition, said process comprising spray drying a slurry of organic and inorganic material, weight ratio of between 0.34 and 0.64 and said slurry having a moisture content of between 25 % and 50 %.

Description

Detergent Compositions

Technical Field

A process for preparing a detergent composition, said process comprising spray drying a slurry of organic and inorganic material, weight ratio of between 0.34 and 0.64 and said slurry having a moisture content of between 25 % and 50% .

Background

Cleaning compositions designed for a number of different functions are well known in the art, as reflected by the number of patents in this field. Traditionally, such cleaning compositions comprise a number of organic and inorganic materials, including for example, a surfactant and a builder. Inorganic materials commonly employed in, especially granular, detergent compositions include for example an alkali metal or alkaline earth metal sulphate. Sulphate, despite being a common component, does not perform any detersive function and is, in the majority of instances, employed as a filler or bulking agent. It is thus the aim of the present invention to provide a suitable detergent composition comprising a reduced amount of sulphate.

Previously, it has been found that reducing or eliminating the sulphate content of a detergent composition results in the detergent composition being predisposed to 'caking' . Caked products do not flow efficiently and are thus not acceptable to the consumer.

Surprisingly, it has been found that reduced sulphate detergent compositions prepared by the process of the present invention are less predisposed to caking than previously described reduced or nil-sulphate compositions.

The applicants have surprisingly found that caking can be minimised by formulating the detergent composition such that the weight ratio of organic^ to inorganic material and the moisture content of the slurry of organic and inorganic material in the crutcher (crutcher mix moisture or CMM) are maintained within a predefined range. In a preferred aspect the detergent compositions prepared by the process of the present invention have density less than 599g/l.

It is further believed that an increase in CMM translates into improved spraying of the slurry into the spray drying tower or atomisability. Whilst it may be expected that this would reduce particle size and therefore increase caking problems, we have surprisingly found that selecting the organic to inorganic ratio and CMM within the predefined limits described herein, potential for caking problems are reduced.

An additional benefit incurred from improved atomisability is the reduction in density of the blown powder collected at the base of the drying tower. The density of the blown powder can also be reduced by injecting air into the organic/inorganic premix slurry. Air injection has an effect akin to steam puffing. An advantage associated with the reduction in density of the detergent compositions prepared by the process of the present invention, is the cost saving incurred by reducing the amount of a component that has little or no detersive action and thus a proportional reduction in transportation cost.

Summary of the invention

According to the present invention there is provided a process for preparing a detergent composition, said process comprising spray drying a slurry of organic and inorganic material, wherein the ratio of organic to inorganic material is from 0.34 to 0.64, and said slurry having a moisture content of between 25 % and 50% .

Detailed description of the invention

Organic Material

The detergent compositions prepared by the process of the present invention comprise an organic material. Essentially any organic material is envisaged for use herein. The preferred organic materials used herein are surfactants. Surfactant

The detergent compositions of the invention contain one or more surfactants selected from anionic, nonionic, non-ester cationic, ampholytic, amphoteric and zwitterionic surfactants and mixtures thereof. Preferred surfactants for use herein are the anionic surfactants, most preferably Linear alkylbenzene sulfonates (LAS) described below.

The surfactant is preferably present as a component of a surfactant system at a level of from 0.1 % to 50% , more preferably from 1 % to 40% by weight, most preferably from 5 % to 30% by weight of the surfactant system.

A typical listing of anionic, nonionic, ampholytic, and zwitterionic classes, and species of these surfactants, is given in U.S. P. 3,929,678 issued to Laughlin and Heuring on December 30, 1975. Further examples are given in "Surface Active Agents and Detergents" (Vol. I and II by Schwartz, Perry and Berch). A list of suitable cationic surfactants is given in U.S. P. 4,259,217 issued to Murphy on March 31 , 1981.

Where present, ampholytic, amphoteric and zwitteronic surfactants are generally used in combination with one or more anionic and/or nonionic surfactants.

Anionic surfactant

Anionic surfactants are preferred components of the compositions prepared by the process of the present invention. Essentially any anionic surfactants useful for detersive purposes are suitable. These can include salts (including, for example, sodium, potassium, ammonium, and substituted ammonium salts such as , di- and triethanolamine salts) of the anionic sulfate, sulfonate, carboxylate and sarcosinate surfactants. Other anionic surfactants include the isethionates such as the acyl isethionates, N-acyl taurates, fatty acid amides of methyl tauride, alkyl succinates and sulfosuccinates, monoesters of sulfosuccinate (especially saturated and unsaturated sulfosuccinate (especially diesters), N-acyl sarcosinates. Resi ds are also suitable, such as rosin, hydrogenated rosin, and resin acids and hydrogenated resin acids present in or derived from tallow oil.

Anionic sulfonate surfactant

Preferred anionic surfactants include the anionic sulfonate surfactants suitable for use herein include the salts of C5-C20 linear alkylbenzene sulfonates, alkyl ester sulfonates, C6-C22 primary or secondary alkane sulfonates, C6-C24 olefin sulfonates, sulfonated polycarboxylic acids, alkyl glycerol sulfonates, fatty acyl glycerol sulfonates, fatty oleyl glycerol sulfonates, and any mixtures thereof.

Anionic sulfate surfactant

Anionic sulfate surfactants suitable for use herein include the linear and branched primary and secondary alkyl sulfates, alkyl ethoxysulfates, fatty oleoyl glycerol sulfates, alkyl phenol ethylene oxide ether sulfates, the C5-C17 acyl-N-(Cι-C4 alkyl) and -N-(Cι-C2 hydroxy alkyl) glucamine sulfates, and sulfates of alkylpolysaccharides such as the sulfates of alkylpolyglucoside (the nonionic nonsulfated compounds being described herein).

Alkyl sulfate surfactants are preferably selected from the linear and branched primary Cio^_Cl8 alkyl sulfates, more preferably the Cn- C15 branched chain alkyl sulfates and the C12- 4 linear chain alkyl sulfates.

Alkyl ethoxysulfate surfactants are preferably selected from the group consisting of the C10-C18 alkyl sulfates which have been ethoxylated with from 0.5 to 20 moles of ethylene oxide per molecule. More preferably, the alkyl ethoxysulfate surfactant is a Cn-Ci8_> most preferably Ci 1-C15 alkyl sulfate which has been ethoxylated with from 0.5 to 7, preferably from 1 to 5, moles of ethylene oxide per molecule.

A particularly preferred aspect of the invention employs mixtures of the preferred alkyl sulfate and alkyl ethoxymonosulfate surfactants. Such mixtures have been disclosed in PCT Patent Application No. WO 93/18124.

Anionic carboxylate surfactant

Suitable anionic carboxylate surfactants include the alkyl ethoxy carboxylates, the alkyl polyethoxy polycarboxylate surfactants and the soaps ('alkyl carboxyls'), especially certain secondary soaps as described herein.

Suitable alkyl ethoxy carboxylates include those with the formula RO(CH2CH2θ)_x CH2COO-M+ wherein R is a C to Cig alkyl group, x ranges from O to 10, and the ethoxy late distribution is such that, on a weight basis, the amount of material where x is 0 is less than 20 % and M is a cation. Suitable alkyl polyethoxy polycarboxylate surfactants include those having the formula RO-(CHRι~CHR2-0)-R3 wherein R is a C to Cjs alkyl group, x is from 1 to 25, R\ and R2 are selected from the group consisting of hydrogen, methyl acid radical, succinic acid radical, hydroxy succinic acid radical, and mixtures thereof, and R3 is selected from the group consisting of hydrogen, substituted or unsubstituted hydrocarbon having between 1 and 8 carbon atoms, and mixtures thereof.

Suitable soap surfactants include the secondary soap surfactants which contain a carboxyl unit connected to a secondary carbon. Preferred secondary soap surfactants for use herein are water-soluble members selected from the group consisting of the water-soluble salts of 2- methyl-1-undecanoic acid, 2-ethyl-l-decanoic acid, 2-propyl-l- nonanoic acid, 2-butyl-l-octanoic acid and 2-pentyl-l-heptanoic acid. Certain soaps may also be included as suds suppressors. Alkali metal sarcosinate surfactant

Other suitable anionic surfactants are the alkali metal sarcosinates of formula R-CON (Rl) CH2 COOM, wherein R is a C5-C17 linear or branched alkyl or alkenyl group, Rl is a C1-C4 alkyl group and M is an alkali metal ion. Preferred examples are the myristyl and oleoyl methyl sarcosinates in the form of their sodium salts.

Alkoxylated nonionic surfactant

Essentially any alkoxylated nonionic surfactants are suitable herein. The ethoxylated and propoxylated nonionic surfactants are preferred.

Preferred alkoxylated surfactants can be selected from the classes of the nonionic condensates of alkyl phenols, nonionic ethoxylated alcohols, nonionic ethoxy lated/propoxylated fatty alcohols, nonionic ethoxy late/propoxy late condensates with propylene glycol, and the nonionic ethoxylate condensation products with propylene oxide/ethylene diamine adducts.

Nonionic alkoxylated alcohol surfactant

The condensation products of aliphatic alcohols with from 1 to 25 moles of alkylene oxide, particularly ethylene oxide and/or propylene oxide, are suitable for use herein. The alkyl chain of the aliphatic alcohol can either be straight or branched, primary or secondary, and generally contains from 6 to 22 carbon atoms. Particularly preferred are the condensation products of alcohols having an alkyl group containing from 8 to 20 carbon atoms with from 2 to 10 moles of ethylene oxide per mole of alcohol.

Nonionic polyhydroxy fatty acid amide surfactant

Polyhydroxy fatty acid amides suitable for use herein are those having the structural formula R2C0NR!Z wherein : Rl is H, C1-C4 hydrocarbyl, 2-hydroxy ethyl, 2-hydroxy propyl, ethoxy, propoxy, or a mixture thereof, preferable C1-C4 alkyl, more preferably Ci or C2 alkyl, most preferably Ci alkyl (i.e. , methyl); and R2 is a C5-C31 hydrocarbyl, preferably straight-chain C5-C19 alkyl or alkenyl, more preferably straight-chain C9-C17 alkyl or alkenyl, most preferably straight-chain C11-C17 alkyl or alkenyl, or mixture thereof; and Z is a polyhydroxyhydrocarbyl having a linear hydrocarbyl chain with at least 3 hydroxyls directly connected to the chain, or an alkoxylated derivative (preferably ethoxylated or propoxylated) thereof. Z preferably will be derived from a reducing sugar in a reductive amination reaction; more preferably Z is a glycityl.

Nonionic fattv acid amide surfactant

Suitable fatty acid amide surfactants include those having the formula: R6C0N(R7)2 wherein R6 is an alkyl group containing from 7 to 21, preferably from 9 to 17 carbon atoms and each R^ is selected from the group consisting of hydrogen, C1-C4 alkyl, C1-C4 hydroxyalkyl, and - (C2H4θ)_xH, where x is in the range of from 1 to 3.

Nonionic alkylpolysaccharide surfactant

Suitable alkylpolysaccharides for use herein are disclosed in U.S. Patent 4,565,647, Llenado, issued January 21 , 1986, having a hydrophobic group containing from 6 to 30 carbon atoms and a polysaccharide, e.g., a polyglycoside, hydrophilic group containing from 1.3 to 10 saccharide units.

Preferred alkylpolyglycosides have the formula

R2θ(C_nH2nO)t(glycosyl)_x

wherein R2 is selected from the group consisting of alkyl, alkylphenyl, hydroxyalkyl, hydroxy alkylphenyl, and mixtures thereof in which the alkyl groups contain from 10 to 18 carbon atoms; n is 2 or 3; t is from 0 to 10, and x is from 1.3 to 8. The glycosyl is preferably derived from glucose. Amphoteric surfactant

Suitable amphoteric surfactants for use herein include the amine oxide surfactants and the alkyl amphocarboxylic acids.

Suitable amine oxides include those compounds having the formula R³(OR4)_XNO(R5)₂ wherein R3 is selected from an alkyl, hydroxyalkyl, acylamidopropoyl and alkyl phenyl group, or mixtures thereof, containing from 8 to 26 carbon atoms; R4 is an alkylene or hydroxy alkylene group containing from 2 to 3 carbon atoms, or mixtures thereof; x is from 0 to 5, preferably from 0 to 3; and each R^ is an alkyl or hydroxyalkyl group containing from 1 to 3, or a polyethylene oxide group containing from 1 to 3 ethylene oxide groups. Preferred are Cιo^_Cl8 alkyl dimethylamine oxide, and CiO-18 acylamido alkyl dimethylamine oxide.

A suitable example of an alkyl aphodicarboxylic acid is Miranol(TM) C2M Cone, manufactured by Miranol, Inc., Dayton, NJ.

Zwitterionic surfactant

Zwitterionic surfactants can also be incorporated into the detergent compositions hereof. These surfactants can be broadly described as derivatives of secondary and tertiary amines, derivatives of heterocyclic secondary and tertiary amines, or derivatives of quaternary ammonium, quaternary phosphonium or tertiary sulfonium compounds. Betaine and sultaine surfactants are exemplary zwitterionic surfactants for use herein.

Suitable betaines are those compounds having the formula R(R')2N+R2COO- wherein R is a C6-Cιg hydrocarbyl group, each Rl is typically C1-C3 alkyl, and R2 is a C1-C5 hydrocarbyl group. Preferred betaines are C 12- 18 dimethyl-ammonio hexanoate and the C10-I8 acylamidopropane (or ethane) dimethyl (or diethyl) betaines. Complex betaine surfactants are also suitable for use herein. Cationfc surfactants

Suitable cationic ester surfactants used in this invention are preferably water dispersible compound having surfactant properties comprising at least one ester (ie -COO-) linkage and at least one cationically charged group.

Other suitable cationic surfactants include the quaternary ammonium surfactants selected from mono Cβ-Ciβ, preferably Cβ-Cio N-alkyl or alkenyl ammonium surfactants wherein the remaining N positions are substituted by methyl, hydroxy ethyl or hydroxypropyl groups. Other suitable cationic ester surfactants, including choline ester surfactants, have for example been disclosed in US Patents No.s 4228042, 4239660 and 4260529.

Inorganic Material

The compositions prepared by the process of the present invention also include an inorganic material. Essentially any inorganic material is envisaged for use herein. Preferred inorganic marterials used herein are builders, alkali metal and alkali earth metal silicates and sulphates.

The organic to inorganic ratio of the composition prepared by the process of the present invetnion are between 0.34 and 0.6, preferably between 0.343 and 0.555, most preferably between 0.36 and 0.48.

Water-soluble builder compound

The compositions prepared by the process of the present invention preferably contain a detergency builder compound. Suitable builder compound include water-soluble builder compound, typically present at a level of from 1 % to 80% by weight, preferably from 10% to 70% by weight, most preferably from 20% to 60% by weight of the composition.

Suitable water-soluble builder compounds include the water soluble monomeric poly carboxylates, or their acid forms, homo or copolymeric polycarboxylic acids or their salts in which the polycarboxylic acid comprises at least two carboxylic radicals separated from each other by not more that two carbon atoms, borates, phosphates, and mixtures of any of the foregoing.

The carboxylate or polycarboxylate builder can be momomeric or oligomeric in type although monomeric polycarboxylates are generally preferred for reasons of cost and performance.

Suitable carboxylates containing one carboxy group include the water soluble salts of lactic acid, glycolic acid and ether derivatives thereof. Polycarboxylates containing two carboxy groups include the water- soluble salts of succinic acid, malonic acid, (ethylenedioxy) diacetic acid, maleic acid, diglycolic acid, tartaric acid, tartronic acid and fumaric acid, as well as the ether carboxylates and the sulfinyl carboxylates. Polycarboxylates containing three carboxy groups include, in particular, water-soluble citrates, aconitrates and citraconates as well as succinate derivatives such as the carboxymethyloxysuccinates described in British Patent No. 1,379,241, lactoxysuccinates described in British Patent No. 1,389,732, and aminosuccinates described in Netherlands Application 7205873, and the oxypolycarboxylate materials such as 2-oxa-l,l,3-propane tricarboxylates described in British Patent No. 1,387,447.

Polycarboxylates containing four carboxy groups include oxydisuccinates disclosed in British Patent No. 1,261,829, 1 , 1,2,2- ethane tetracarboxylates, 1, 1,3,3-propane tetracarboxylates and 1,1,2,3-propane tetracarboxylates. Polycarboxylates containing sulfo substituents include the sulfosuccinate derivatives disclosed in British Patent Nos. 1 ,398,421 and 1,398,422 and in U.S. Patent No. 3,936,448, and the sulfonated pyrolysed citrates described in British Patent No. 1,439,000. Preferred polycarboxylates are hydroxycarboxylates containing up to three carboxy groups per molecule, more particularly citrates.

The parent acids of the monomeric or oligomeric polycarboxylate chelating agents or mixtures thereof with their salts, e.g. citric acid or citrate/citric acid mixtures are also contemplated as useful builder components.

Borate builders, as well as builders containing borate-forming materials that can produce borate under detergent storage or wash conditions are useful water-soluble builders herein.

Suitable examples of water-soluble phosphate builders are the alkali metal tripolyphosphates, sodium, potassium and ammonium pyrophosphate, sodium and potassium and ammonium pyrophosphate, sodium and potassium orthophosphate, sodium polymeta/phosphate in which the degree of polymerization ranges from about 6 to 21, and salts of phytic acid.

Partially soluble or insoluble builder compound

Other suitable builder compounds include the partially soluble or insoluble builder compounds, typically present at a level of from 1 % to 80% by weight, preferably from 10% to 70% by weight, most preferably from 20% to 60% weight of the composition.

Examples of largely water insoluble builders include the Odium aluminosilicates.

Suitable aluminosilicate zeolites have the unit cell formula Na_z[(Alθ2)z(Siθ2)y] . XH2O wherein z and y are at least 6; the molar ratio of z to y is from 1.0 to 0.5 and x is at least 5, preferably from 7.5 to 276, more preferably from 10 to 264. The aluminosilicate material are in hydrated form and are preferably crystalline, containing from 10% to 28%, more preferably from 18% to 22% water in bound form.

The aluminosilicate zeolites can be naturally occurring materials, but are preferably synthetically derived. Synthetic crystalline aluminosilicate ion exchange materials are available under the designations Zeolite A, Zeolite B, Zeolite P, Zeolite X, Zeolite HS and mixtures thereof. Zeolite A has the formula Na 12 EA102) 12 (Si0₂)ι₂] . xH₂0

wherein x is from 20 to 30, especially 27. Zeolite X has the formula Na86 [(Alθ2)86(Siθ2)l06] - 276 H2O. Zeolite MAP, as disclosed in EP-B-384,070 is a preferred zeolite builder herein.

Alkalinity system

Additional suitable inorganic materials also inlcude those used as components of the alkalinity system. The alkalinity system were present is at levels of from 1.5 % to 95 % , preferably from 5 % to 60% , most preferably from 10% to 40% by weight of the composition Components of an alkalinity system comprise components capable of providing alkalinity species in solution. By alkalinity species it is meant for the purposes of this invention: carbonate, bicarbonate, hydroxide and the various silicate anions. Such alkalinity species can be formed for example, when alkaline salts selected from alkali metal or alkaline earth carbonate, bicarbonate, hydroxide or silicate, including crystalline layered silicate, salts and any mixtures thereof are dissolved in water. Alkali metal silicate salts are preferred components of the detergent cmpositions prepared herein.

Sulphate

The compositions prepared by the process of the present invention preferably contain an alkali metal or alkali earth metal sulphate. A preferred sulphate used herein is anhydrous sodium sulphate.

Preparation of the Detergent composition

The compositions of the present invention are prepared in a two stage conventional spray drying process. Stage one comprises mixing the organic and inorganic materials in a conventional large blender-type piece of equipment, commonly known as a crutcher. The resulting premix is in the form of a slurry having a moisture content (crutcher mix moisture or CMM) of between 25 % and 50% , preferably between 30 and 45% , most preferably between 34% and 43 % . The slurry is pumped to a height, such that it can be sprayed into the spray drying tower of stage two.

The spray drying tower is heated to between 80 and 350°C. As the organic and inorganic materials in the slurry fall in the tower, moisture is driven off. Eventually particles of organic and inorganic material collect at the base of the tower. Particles formed in the spray drying tower are known as blown powder. In an additional stage, any remaining components of the detergent composition may be dry mixed with or sprayed onto the blown powder.

All equipment used in the crutching and spray drying process are conventional. Variations of this process are also envisaged. In a preferres embodiment of the present invention air is injected into the crutcher mix before it is sprayed into the spray drying tower.

Additional detergent components

The additional organic or inorganic detergent components listed below may be incorporated into the detergent composition. Where the additional components are included as part of the slurry intended for forming the blown powder, they are also to be included for calculation of the organic to inorganic ratio.

The detergent compositions prepared by the process of the present invention may contain a variety of additional detergent components. The precise nature of these components, and levels of incorporation thereof will depend on the physical form of the composition, and the precise nature of the washing operation for which it is to be used.

The compositions of the invention preferably contain one or more detergent components selected from additional surfactants, additional builders, alkalinity system, bleach, organic polymeric compounds, enzymes, enzyme stabilising system, suds suppressors, lime soap dispersants, soil suspension and anti-redeposition agents and corrosion inhibitors. Organic peroxyacid bleaching system

A optional feature of detergent compositions prepared herein, is an organic peroxyacid bleaching system. In one preferred execution the bleaching system contains a hydrogen peroxide source and an organic peroxyacid bleach precursor compound. The production of the organic peroxyacid occurs by an in situ reaction of the precursor with a source of hydrogen peroxide. Preferred sources of hydrogen peroxide include inorganic perhydrate bleaches. In an alternative preferred execution a preformed organic peroxyacid is incorporated directly into the composition. Compositions containing mixtures of a hydrogen peroxide source and organic peroxyacid precursor in combination with a preformed organic peroxyacid are also envisaged.

Inorganic perhydrate bleaches

Inorganic perhydrate salts are a preferred source of hydrogen peroxide. These salts are normally incorporated in the form of the alkali metal, preferably sodium salt at a level of from 1 % to 40% by weight, more preferably from 2% to 30% by weight and most preferably from 5 % to 25% by weight of the compositions.

Examples of inorganic perhydrate salts include perborate, percarbonate, perphosphate, persulfate and persilicate salts. The inorgamc perhydrate salts are normally the alkali metal salts. The inorganic perhydrate salt may be included as the crystalline solid without additional protection. For certain perhydrate salts however, the preferred executions of such granular compositions utilize a coated form of the material which provides better storage stability for the perhydrate salt in the granular product. Suitable coatings comprise inorganic salts such as alkali metal silicate, carbonate or borate salts or mixtures thereof, or organic materials such as waxes, oils, or fatty soaps.

Sodium perborate is a preferred perhydrate salt and can be in the form of the monohydrate of nominal formula NaBθ2H2θ2 or the tetrahydrate NaBθ2H2θ2-3H2θ. Alkali metal percarbonates, particularly sodium percarbonate are preferred perhydrates herein. Sodium percarbonate is an addition compound having a formula corresponding to 2Na2Cθ3.3H2θ2, and is available commercially as a crystalline solid.

Potassium peroxymonopersulfate is another inorganic perhydrate salt of use in the detergent compositions herein.

Peroxyacid bleach precursor

Peroxyacid bleach precursors are compounds which react with hydrogen peroxide in a perhydrolysis reaction to produce a peroxyacid. Generally peroxyacid bleach precursors may be represented as

O X- C -L

where L is a leaving group and X is essentially any functionality, such that on perhydroloysis the structure of the peroxyacid produced is

O

X -C - OOH

Peroxyacid bleach precursor compounds are preferably incorporated at a level of from 0.5% to 20% by weight, more preferably from 1 % to 15 % by weight, most preferably from 1.5 % to 10% by weight of the detergent compositions.

Suitable peroxyacid bleach precursor compounds typically contain one or more N- or O-acyl groups, which precursors can be selected from a wide range of classes. Suitable classes include anhydrides, esters, imides, lactams and acylated derivatives of imidazoles and oximes. Examples of useful materials within these classes are disclosed in GB- A- 1586789. Suitable esters are disclosed in GB-A-836988, 864798, 1147871, 2143231 and EP-A-0170386. Leaving groups

The leaving group, hereinafter L group, must be sufficiently reactive for the perhydrolysis reaction to occur within the optimum time frame (e.g., a wash cycle). However, if L is too reactive, this activator will be difficult to stabilize for use in a bleaching composition.

Preferred L groups are selected from the group consisting of:

R³ Y

I I

-O-CH= =C- CH= =CH₂ -O-CH=C-CH=CH₂

R³ O Y

¹ N I

-O-C=CHR⁴ , and — N— S-CH— R⁴

R³ O

and mixtures thereof, wherein R is an alkyl, aryl, or alkaryl group containing from 1 to 14 carbon atoms, R is an alkyl chain contaimng from 1 to 8 carbon atoms, R is H or R , and Y is H or a solubilizing group. Any of R , R and R may be substituted by essentially any functional group including, for example alkyl, hydroxy, alkoxy, halogen, amine, nitrosyl, amide and ammonium or alkyl ammmonium groups

The preferred solubilizing groups are -SO^^'M ⁺ , -CO^^'M , -S0₄ ^"M ⁺ , -N ⁺ (R³)₄X^" and 0 < -N(R³)₃ and most preferably -SO^^'M and -Cθ2^~M wherein R³ is an alkyl chain containing from 1 to 4 carbon atoms, M is a cation which provides solubility to the bleach activator and X is an anion which provides solubility to the bleach activator. Preferably, M is an alkali metal, ammonium or substituted ammonium cation, with sodium and potassium being most preferred, and X is a halide, hydroxide, methylsulfate or acetate anion.

Alkyl percarboxylic acid bleach precursors

Alkyl percarboxylic acid bleach precursors form percarboxylic acids on perhydrolysis. Preferred precursors of this type provide peracetic acid on perhydrolysis.

Preferred alkyl percarboxylic precursor compounds of the imide type include the N-,N,N Nl tetra acetylated alkylene diamines wherein the alkylene group contains from 1 to 6 carbon atoms, particularly those compounds in which the alkylene group contains 1 , 2 and 6 carbon atoms. Tetraacetyl ethylene diamine (TAED) is particularly preferred.

Other preferred alkyl percarboxylic acid precursors include sodium 3,5,5-tri-methyl hexanoyloxy benzene sulfonate (iso-NOBS), sodium nonanoyloxybenzene sulfonate (NOBS), sodium acetoxybenzene sulfonate (ABS) and pentaacetyl glucose.

Amide substituted alkyl peroxyacid precursors

Amide substituted alkyl peroxyacid precursor compounds are suitable herein, including those of the following general formulae:

_R1 — _c — _N — _R2 — _c — _{L R}1 — _N — _c — _R2 — _c — 1_

O R⁵ O or R⁵ O O wherein Rl is an alkyl group with from 1 to 14 carbon atoms, R2 is an alkylene group containing from 1 to 14 carbon atoms, and R5 is H or an alkyl group containing 1 to 10 carbon atoms and L can be essentially any leaving group. Amide substituted bleach activator compounds of this type are described in EP-A-0170386.

Perbenzoic acid precursor

Perbenzoic acid precursor compounds provide perbenzoic acid on perhydrolysis. Suitable O-acylated perbenzoic acid precursor compounds include the substituted and unsubstituted benzoyl oxy benzene sulfonates, and the benzoylation products of sorbitol, glucose, and all saccharides with benzoylating agents, and those of the imide type including N-benzoyl succinimide, tetrabenzoyl ethylene diamine and the N-benzoyl substituted ureas. Suitable imidazole type perbenzoic acid precursors include N-benzoyl imidazole and N-benzoyl benzimidazole. Other useful N-acyl group-containing perbenzoic acid precursors include N-benzoyl pyrrolidone, dibenzoyl taurine and benzoyl pyroglutamic acid.

Cationic peroxyacid precursors

Cationic peroxyacid precursor compounds produce cationic peroxyacids on perhydrolysis.

Typically, cationic peroxyacid precursors are formed by substituting the peroxyacid part of a suitable peroxyacid precursor compound with a positively charged functional group, such as an ammonium or alkyl ammmonium group, preferably an ethyl or methyl ammonium group. Cationic peroxyacid precursors are typically present in the solid detergent compositions as a salt with a suitable anion, such as a halide ion.

The peroxyacid precursor compound to be so cationically substituted may be a perbenzoic acid, or substituted derivative thereof, precursor compound as described hereinbefore. Alternatively, the peroxyacid precursor compound may be an alkyl percarboxylic acid precursor compound or an amide substituted alkyl peroxyacid precursor as described hereinafter

Cationic peroxyacid precursors are described in U.S. Patents 4,904,406; 4,751 ,015; 4,988,451 ; 4,397,757; 5,269,962; 5, 127,852; 5,093,022; 5, 106,528; U.K. 1 ,382,594; EP 475,512, 458,396 and 284,292; and in JP 87-318,332.

Examples of preferred cationic peroxyacid precursors are described in UK Patent Application No. 9407944.9 and US Patent Application Nos. 08/298903, 08/298650, 08/298904 and 08/298906.

Suitable cationic peroxyacid precursors include any of the ammonium or alkyl ammonium substituted alkyl or benzoyl oxybenzene sulfonates, N-acylated caprolactams, and monobenzoyltetraacetyl glucose benzoyl peroxides. Preferred cationic peroxyacid precursors of the N-acylated caprolactam class include the trialkyl ammonium methylene benzoyl caprolactams and the trialkyl ammonium methylene alkyl caprolactams.

Benzoxazin organic peroxyacid precursors

Also suitable are precursor compounds of the benzoxazin-type, as disclosed for example in EP-A-332,294 and EP-A-482,807, particularly those having the formula:

wherein Ri is H, alkyl, alkaryl, aryl, or arylalkyl. Preformed organic peroxyacid

The organic peroxyacid bleaching system may contain, in addition to, or as an alternative to, an organic peroxyacid bleach precursor compound, a preformed organic peroxyacid , typically at a level of from 1 % to 15% by weight, more preferably from 1 % to 10% by weight of the composition.

A preferred class of organic peroxyacid compounds are the amide substituted compounds of the following general formulae:

|

I I

O R⁵ O or

wherein Rl is an alkyl, aryl or alkaryl group with from 1 to 14 carbon atoms, R2 is an alkylene, arylene, and alkarylene group containing from 1 to 14 carbon atoms, and R5 is H or an alkyl, aryl, or alkaryl group containing 1 to 10 carbon atoms. Amide substituted organic peroxyacid compounds of this type are described in EP-A-0170386.

Other organic peroxy acids include diacyl and tetraacylperoxides, especially diperoxydodecanedioc acid, diperoxytetradecanedioc acid and diperoxyhexadecanedioc acid, and diperazelaic acid, and diperbrassylic acid and N-phthaloylaminoperoxicaproic acid are also suitable herein.

Bleach catalyst

The compositions optionally contain a transition metal containing bleach catalyst. One suitable type of bleach catalyst is a catalyst system comprising a heavy metal cation of defined bleach catalytic activity, such as copper, iron, cobalt or manganese cations, an auxiliary metal cation having little or no bleach catalytic activity, such as zinc or aluminum cations, and a sequestrant having defined stability constants for the -catalytic and auxiliary metal cations, particularly ethylenediaminetetraacetic acid, ethylenediaminetetre (methylenephosphonic acid) and water-soluble salts thereof. Such catalysts are disclosed in U.S. Pat. 4,430,243.

Other types of bleach catalysts include the manganese-based complexes disclosed in U.S. Pat. 5,246,621 and U.S. Pat. 5,244,594. Preferred examples of these catalysts include MnlV2(u-0)3(l,4,7-trimethyl- l,4,7-triazacyclononane)2-(PF6)2, Mn^III2(^u-0)l(u-OAc)2(l,4,7- trimethyl-1 ,4 ,4,7- triazacyclono ,4,7- trimethyl-l,4,7-triazacyclononane)2-(C104)3, and mixtures thereof. Others are described in European patent application publication no. 549,272. Other ligands suitable for use herein include 1 ,5,9-trimethyl- 1,5, 9-triazacy clododecane , 2-methy 1- 1,4, 7-triazacy clononane , 2- methy 1- 1 ,4, 7-triazacy clononane , 1,2,4, 7-tetramethy 1- 1 ,4,7- triazacy clononane, and mixtures thereof.

For examples of suitable bleach catalysts see U.S. Pat. 4,246,612 and U.S. Pat. 5,227,084. See also U.S. Pat. 5,194,416 which teaches mononuclear manganese (IV) complexes such as Mn(l,4,7-trimethyl- l ,4,7-triazacyclononane)(OCH3)3_(PF6). Still another. ty^.e of bleach catalyst, as disclosed in U.S. Pat. 5, 114,606, is a water-soluble complex of manganese (III), and/or (IV) with a ligand which is a non- carboxylate polyhydroxy compound having at least three consecutive C-OH groups. Other examples include binuclear Mn complexed with tetra-N-dentate and bi-N-dentate ligands, including N4MnIH(u- 0)2MnI N₄)+and [Bipy2Mnπi(_u-0)2MnI bipy2]-(Clθ4)3.

Further suitable bleach catalysts are described, for example, in European patent application No. 408,131 (cobalt complex catalysts), European patent applications, publication nos. 384,503, and 306,089 (metallo-porphyrin catalysts), U.S. 4,728,455 (manganese/multidentate ligand catalyst), U.S. 4,711,748 and European patent application, publication no. 224,952, (absorbed manganese on aluminosilicate catalyst), U.S. 4,601,845 (aluminosilicate support with manganese and zinc or magnesium salt), U.S. 4,626,373 (manganese/ligand catalyst), U.S. 4,119,557 (ferric complex catalyst), German Pat. specification 2,054,019 (cobalt chelant catalyst) Canadian 866,191 (transition metal- containing salts), U.S. 4,430,243 (chelants with manganese cations and non-catalytic metal cations), and U.S. 4,728,455 (manganese gluconate catalysts).

Enzyme

Suitable enzymatic materials include the commercially available lipases, cutinases, amylases, neutral and alkaline proteases, esterases, cellulases, pectinases, lactases and peroxidases conventionally incorporated into detergent compositions. Preferred enzymes are discussed in US Patents 3,519,570 and 3,533, 139.

Enzymes are normally incorporated into detergent or detergent additive compositions at levels sufficient to provide a "cleaning-effective amount" . The term "cleaning effective amount" refers to any amount capable of producing a cleaning, stain removal, whitening, deodorizing, or freshness improving effect on substrates. In practical terms for current commercial preparations, typical amounts are up to 5 mg by weight, more typically 0.01 mg to 3 mg, of active enzyme per gram of the detergent composition. Stated otherwise, the compositions herein will typically comprise from 0.001 % to 5 %, preferably from 0.01 % to 1 % by weight of a commercial enzyme preparation.

Preferred commercially available protease enzymes include those sold under the tradenames Alcalase, Savinase, Primase, Durazym, and Esperase by Novo Industries A/S (Denmark), those sold under the tradename Maxatase, Maxacal and Maxapem by Gist-Brocades, those sold by Genencor International, and those sold under the tradename Opticlean and Optimase by Solvay Enzymes. As well as Protease A as disclosed in EP 130,756 A, January 9, 1985 and Protease B as disclosed in EP 303,761 A, April 28, 1987 and EP 130,756 A, January 9, 1985. See also a high pH protease from Bacillus sp. NCIMB 40338 described in WO 9318140 A to Novo. Enzymatic detergents comprising protease, one or more other enzymes, and a reversible protease inhibitor are described in WO 9203529 A to Novo. Other preferred proteases include those of WO 9510591 A to Procter & Gamble. When desired, a protease having decreased absorption and increased hydrolysis is available as described in WO 9507791 to Procter and Gamble. A recombinant trypsin-like protease for detergents suitable herein is described in WO 9425583 to Novo.

In more detail, an especially preferred protease, referred to as "Protease D" is a carbonyl hydrolase variant having an amino acid sequence not found in nature, which is derived from a precursor carbonyl hydrolase by substituting a different amino acid for a plurality of amino acid residues at a position in said carbonyl hydrolase equivalent to position +76, preferably also in combination with one or more amino acid residue positions equivalent to those selected from the group consisting of +99, + 101, + 103, + 104, + 107, + 123, +27, + 105, + 109, + 126, + 128, + 135, + 156, + 166, + 195, + 197, +204, +206, +210, +210, +216, +217, +218, +222, +260, +265, and/or +274 according to the numbering of Bacillus amyloliquefaciens subtilisin, as described in the patent applications of A. Baeck, et al, entitled "Protease-Containing Cleaning Compositions" having US Serial No. 08/322,676, and C Ghosh, et al, "Bleaching Compositions Comprising Protease Enzymes" having US Serial No. 08/322,677, both filed October 13, 1994.

Protease enzyme may be incorporated into the compositions in accordance with the invention at a level of from 0.0001 % to 4% active enzyme by weight of the composition.

Preferred amylases include, for example, α-amylases obtained from a special strain of B licheniformis, described in more detail in GB- 1,269,839 (Novo). Preferred commercially available amylases include for example, those sold under the tradename Rapidase by Gist- Brocades, and those sold under the tradename Termamyl fungamyl and BAN by Novo Industries A/S.

Engineering of enzymes for improved stability, e.g., oxidative stability, is known. See, for example J. Biological Chem. , Vol. 260, No. 11, June 1985, pp. 6518-6521. Certain preferred embodiments of the present compositions can make use of amylases having improved stability in detergents such as automatic dishwashing types, especially improved oxidative stability as measured against a reference-point of TERM AM YL® in commercial use in 1993. These preferred amylases herein share the characteristic of being "stability-enhanced" amylases, characterized, at a minimum, by a measurable improvement in one or more of: oxidative stability, e.g. , to hydrogen peroxide / tetraacetylethylenediamine in buffered solution at pH 9-10; thermal stability, e.g. , at common wash temperatures such as about 60°C; or alkaline stability, e.g., at a pH from about 8 to about 11 , measured versus the above-identified reference-point amylase. Stability can be measured using any of the art-disclosed technical tests. See, for example, references disclosed in WO 9402597. Stability-enhanced amylases can be obtained from Novo or from Genencor International. One class of highly preferred amylases herein have the commonality of being derived using site-directed mutagenesis from one or more of the Bacillus amylases, especially the Bacillus α-amylases, regardless of whether one, two or multiple amylase strains are the immediate precursors. Oxidative stability-enhanced amylases vs. the above- identified reference amylase are preferred for use, especially in bleaching, more preferably oxygen bleaching, as distinct from chlorine bleaching, detergent compositions herein. Such preferred amylases include (a) an amylase according to the hereinbefore incorporated WO 9402597, Novo, Feb. 3, 1994, as further illustrated by a mutant in which substitution is made, using alanine or threonine, preferably threonine, of the methionine residue located in position 197 of the B. licheniformis alpha-amylase, known as TERM AM YL®, or the homologous position variation of a similar parent amylase, such as B. amyloliquefaciens, B. subtilis, or B. stearothermophilus; (b) stability- enhanced amylases as described by Genencor International in a paper entitled "Oxidatively Resistant alpha- Amylases" presented at the 207th American Chemical Society National Meeting, March 13-17 1994, by C. Mitchinson. Therein it was noted that bleaches in automatic dishwashing detergents inactivate alpha-amylases but that improved oxidative stability amylases have been made by Genencor from B licheniformis NCIB8061. Methionine (Met) was identified as the most likely residue to be modified. Met was substituted, one at a time, in positions 8, 15, 197, 256, 304, 366 and 438 leading to specific mutants, particularly important being M197L and M197T with the M197T variant being the most stable expressed variant. Stability was measured in CASCADE® and SUNLIGHT®; (c) particularly preferred amylases herein include amylase variants having additional modification in the immediate parent as described in WO 9510603 A and are available from the assignee, Novo, as DURAMYL®. Other particularly preferred oxidative stability enhanced amylase include those described in WO 9418314 to Genencor International and WO 9402597 to Novo. Any other oxidative stability-enhanced amylase can be used, for example as derived by site-directed mutagenesis from known chimeric, hybrid or simple mutant parent forms of available amylases. Other preferred enzyme modifications are accessible. See WO 9509909 A to Novo.

Other amylase enzymes include those described in WO 95/26397 and in co-pending application by Novo Nordisk PCT/DK96/00056. Specific amylase enzymes for use in the detergent compositions of the present invention include α-amylases characterized by having a specific activity at least 25 % higher than the specific activity of Termamyl® at a temperature range of 25°C to 55°C and at a pH value in the range of 8 to 10, measured by the Phadebas® α-amylase activity assay. (Such Phadebas® α-amylase activity assay is described at pages 9-10, WO 95/26397.) Also included herein are α-amylases which are at least 80% homologous with the amino acid sequences shown in the SEQ ID listings in the references. Amylase enzyme may be incorporated into the composition in accordance with the invention at a level of from 0.0001 % to 2% active enzyme by weight of the composition.

Lipolytic enzyme may be present at levels of active lipolytic enzyme of from 0.0001 % to 2% by weight, preferably 0.001 % to 1 % by weight, most preferably from 0.001 % to 0.5 % by weight of the compositions.

The lipase may be fungal or bacterial in origin being obtained, for example, from a lipase producing strain of Humicola sp., Thermomyces sp. or Pseudomonas sp. including Pseudomonas pseudoalcaligenes or Pseudomas fluorescens. Lipase from chemically or genetically modified mutants of these strains are also useful herein. A preferred lipase is derived from Pseudomonas pseudoalcaligenes . which is described in Granted European Patent, EP-B-0218272.

Another preferred lipase herein is obtained by cloning the gene from Humicola lanuginosa and expressing the gene in Aspergillus oryza, as host, as described in European Patent Application, EP-A-0258 068, which is commercially available from Novo Industri A/S, Bagsvaerd, Denmark, under the trade name Lipolase. This lipase is also described in U.S. Patent 4,810,414, Huge-Jensen et al, issued March 7, 1989.

Cutinase enzymes suitable for use herein are described in WO 8809367 A to Genencor.

Peroxidase enzymes may be used in combination with oxygen sources, e.g., percarbonate, perborate, hydrogen peroxide, etc., for "solution bleaching" or prevention of transfer of dyes or pigments removed from substrates during the wash to other substrates present in the wash solution. Known peroxidases include horseradish peroxidase, ligninase, and haloperoxidases such as chloro- or bromo-peroxidase. Peroxidase-containing detergent compositions are diseased in WO 89099813 A, October 19, 1989 to Novo and WO 8909813 A to Novo.

Enzyme Stabilizing System

A preferred component of enzyme-containing compositions is an enzyme stabilising system. When present the enzyme stabilising system is at levels of from 0.001 % to 10%, preferably from 0.005% to 8%, most preferably from 0.01 % to 6% , by weight of the composition. The enzyme stabilizing system can be any stabilizing system which is compatible with the detersive enzyme. Such stabilizing systems can comprise calcium ion, boric acid, propylene glycol, short chain carboxy lie acid, boronic acid, chlorine bleach scavengers and mixtures thereof. Such stabilizing systems can also comprise reversible enzyme inhibitors, such as reversible protease inhibitors. Heavy metal ion sequestrant

The detergent compositions prepared by the process of the invention preferably contain as an optional component a heavy metal ion sequestrant. By heavy metal ion sequestrant it is meant herein components which act to sequester (chelate) heavy metal ions. These components may also have calcium and magnesium chelation capacity, but preferentially they show selectivity to binding heavy metal ions such as iron, manganese and copper.

Heavy metal ion sequestrants are generally present at a level of from 0.005 % to 20% , preferably from 0.1 % to 10% , more preferably from 0.25 % to 7.5 % and most preferably from 0.5 % to 5 % by weight of the compositions.

Suitable heavy metal ion sequestrants for use herein include organic phosphonates, such as the amino alkylene poly (alkylene phosphonates), alkali metal ethane 1 -hydroxy disphosphonates and nitrilo trimethylene phosphonates.

Preferred among the above species are diethylene triamine penta (methylene phosphonate), ethylene diamine tri (methylene phosphonate) hexamethylene diamine tetra (methylene phosphonate) and hydroxy-ethylene 1,1 diphosphonate.

Other suitable heavy metal ion sequestrant for use herein include nitrilotriacetic acid and polyaminocarboxylic acids such as ethylenediaminotetracetic acid, ethylenetriamine pentacetic acid, ethylenediamine disuccinic acid, ethylenediamine diglutaric acid, 2- hydroxypropylenediamine disuccinic acid or any salts thereof. Especially preferred is ethylenediamine-N,N' -disuccinic acid (EDDS) or the alkali metal, alkaline earth metal, ammonium, or substituted ammonium salts thereof, or mixtures thereof.

Other suitable heavy metal ion sequestrants for use herein are iminodiacetic acid derivatives such as 2-hydroxyethyl diacetic acid or glyceryl imino diacetic acid, described in EP-A-317,542 and EP-A- 399, 133. The iminodiacetic acid-N-2-hydroxypropyl sulfonic acid and aspartic acid N-carboxymethyl N-2-hydroxypropyl-3-sulfonic acid sequestrants described in EP-A-516,102 are also suitable herein. The β -alanine-N,N' -diacetic acid, aspartic acid-N,N' -diacetic acid, aspartic acid-N-monoacetic acid and iminodisuccinic acid sequestrants described in EP-A-509,382 are also suitable.

EP-A-476,257 describes suitable amino based sequestrants. EP-A- 510,331 describes suitable sequestrants derived from collagen, keratin or casein. EP-A-528,859 describes a suitable alkyl iminodiacetic acid sequestrant. Dipicolinic acid and 2-phosphonobutane- 1 ,2,4- tricarboxylic acid are also suitable. Glycinamide-N,N' -disuccinic acid (GADS), ethylenediamine-N-N'-diglutaric acid (EDDG) and 2- hydroxypropylenediamine-N-N' -disuccinic acid (HPDDS) are also suitable.

Organic polymeric compound

Organic polymeric compounds are optional components of the detergent compositions prepared in accord with the invention, and are preferably present as components of any particulate components where they may act such as to bind the particulate component together. By organic polymeric compound it is meant herein essentially any polymeric organic compound commonly used as dispersants, and anti- redeposition and soil suspension agents in detergent compositions, including any of the high molecular weight organic polymeric compounds described as clay flocculating agents herein.

Organic polymeric compound is typically incoφorated in the detergent compositions of the invention at a level of from 0.1 % to 30% , preferably from 0.5 % to 15 % , most preferably from 1 % to 10% by weight of the compositions.

Examples of organic polymeric compounds include the water soluble organic homo- or co-polymeric polycarboxylic acids or their salts in which the polycarboxylic acid comprises at least two carboxyl radicals separated from each other by not more than two carbon atoms. Polymers of the latter type are disclosed in GB-A-1 ,596,756. Examples of such salts are polyacrylates of MWt 2000-5000 and their copolymers with maleic anhydride, such copolymers having a molecular weight of from 20,000 to 100,000, especially 40,000 to 80,000.

The polyamino compounds are useful herein including those derived from aspartic acid such as those disclosed in EP-A-305282, EP-A- 305283 and EP-A-351629.

Teφolymers containing monomer units selected from maleic acid, acrylic acid, poly aspartic acid and vinyl alcohol, particularly those having an average molecular weight of from 5,000 to 10,000, are also suitable herein.

Other organic polymeric compounds suitable for incoφoration in the detergent compositions herein include cellulose derivatives such as methy lcellulose , carboxymethylcellulose , hydroxypropylmethylcellulose and hydroxy ethylcellulose.

Further useful organic polymeric compounds are the polyethylene glycols, particularly those of molecular weight 1000-10000, more particularly 2000 to 8000 and most preferably about 4000.

Suds suppressing system

The detergent compositions of the invention may comprise a suds suppressing system. Where present such a sytem is found at a level of from 0.01 % to 15 %, preferably from 0.05% to 10%, most preferably from 0.1 % to 5% by weight of the composition.

Suitable suds suppressing systems for use herein may comprise essentially any known antifoam compound, including, for example silicone antifoam compounds and 2-alkyl alcanol antifoam compounds. By antifoam compound it is meant herein any compound or mixtures of compounds which act such as to depress the foaming or sudsing produced by a solution of a detergent composition, particularly in the presence of agitation of that solution.

Particularly preferred antifoam compounds for use herein are silicone antifoam compounds defined herein as any antifoam compound including a silicone component. Such silicone antifoam compounds also typically contain a silica component. The term "silicone" as used herein, and in general throughout the industry, encompasses a variety of relatively high molecular weight polymers containing siloxane units and hydrocarbyl group of various types. Preferred silicone antifoam compounds are the siloxanes, particularly the polydimethylsiloxanes having trimethylsilyl end blocking units.

Other suitable antifoam compounds include the monocarboxylic fatty acids and soluble salts thereof. These materials are described in US Patent 2,954,347, issued September 27, 1960 to Wayne St. John. The monocarboxylic fatty acids, and salts thereof, for use as suds suppressor typically have hydrocarbyl chains of 10 to 24 carbon atoms, preferably 12 to 18 carbon atoms. Suitable salts include the alkali metal salts such as sodium, potassium, and lithium salts, and ammonium and alkanolammonium salts.

Other suitable antifoam compounds include, for example, high molecular weight fatty esters (e.g. fatty acid triglycerides), fatty acid esters of monovalent alcohols, aliphatic C18-C40 ketones (e.g. stearone) N-alkylated amino triazines such as tri- to hexa- alkylmelamines or di- to tetra alkyldiamine chlortriazines formed as products of cyanuric chloride with two or three moles of a primary or secondary amine containing 1 to 24 carbon atoms, propylene oxide, bis stearic acid amide and monostearyl di-alkali metal (e.g. sodium, potassium, lithium) phosphates and phosphate esters. A preferred suds suppressing system comprises

(a) antifoam compound, preferably silicone antifoam compound, most preferably a silicone antifoam compound comprising in combination

(i) poly dimethyl siloxane, at a level of from 50% to 99% , preferably 75 % to 95 % by weight of the silicone antifoam compound; and

(ii) silica, at a level of from 1 % to 50% , preferably 5 % to 25% by weight of the silicone/silica antifoam compound;

wherein said silica/silicone antifoam compound is incoφorated at a level of from 5% to 50% , preferably 10% to 40% by weight;

(b) a dispersant compound, most preferably comprising a silicone glycol rake copolymer with a polyoxyalkylene content of 72- 78 % and an ethylene oxide to propylene oxide ratio of from 1:0.9 to 1:1.1, at a level of from 0.5% to 10%, preferably 1 % to 10% by weight; a particularly preferred silicone glycol rake copolymer of this type is DC0544, commercially available from DOW Corning under the tradename DC0544;

(c) an inert carrier fluid compound, most preferably comprising a C16-C18 ethoxylated alcohol with a degree of ethoxy lation of from 5 to 50, preferably 8 to 15, at a level of from 5% to 80% , preferably 10% to 70% , by weight;

A highly preferred particulate suds suppressing system is described in EP-A-0210731 and comprises a silicone antifoam compound and an organic carrier material having a melting point in the range 50 °C to 85 °C, wherein the organic carrier material comprises a monoester of glycerol and a fatty acid having a carbon chain containing from 12 to 20 carbon atoms. EP-A-0210721 discloses other preferred particulate suds suppressing systems wherein the organic carrier material is a fatty acid or alcohol having a carbon chain containing from 12 to 20 carbon atoms, or a mixture thereof, with a melting point of from 45 °C to 80°C.

Clav softening system

The detergent compositions may contain a clay softening system comprising a clay mineral compound and optionally a clay flocculating agent.

The clay mineral compound is preferably a smectite clay compound. Smectite clays are disclosed in the US Patents No.s 3,862,058, 3,948,790, 3,954,632 and 4,062,647. European Patents No.s EP-A- 299,575 and EP-A-313,146 in the name of the Procter and Gamble Company describe suitable organic polymeric clay flocculating agents.

Polymeric dve transfer inhibiting agents

The detergent compositions herein may also comprise from 0.01 % to 10%, preferably from 0.05% to 0.5% by weight of polymeric dye transfer inhibiting agents.

The polymeric dye transfer inhibiting agents are preferably selected from polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, polyvinylpyrrolidonepolymers or combinations thereof.

a) Polvamine N-oxide polymers

Polyamine N-oxide polymers suitable for use herein contain units having the following structure formula :

I

(I) Ax

I wherein P is a polymerisable unit, and

O O O

A is NC, CO, C, -O-, -S-, -N-; x is O or 1 ;

R are aliphatic, ethoxylated aliphatics, aromatic, heterocyclic or alicyclic groups or any combination thereof whereto the nitrogen of the N-0 group can be attached or wherein the nitrogen of the N-0 group is part of these groups.

The N-0 group can be represented by the following general structures :

O

▲

<^R3>z _or = N-(R₁)x

wherein Rl, R2, and R3 are aliphatic groups, aromatic, heterocyclic or alicyclic groups or combinations thereof, x or/and y or/and z is 0 or 1 and wherein the nitrogen of the N-0 group can be attached or wherein the nitrogen of the N-0 group forms part of these groups. The N-0 group can be part of the polymerisable unit (P) or can be attached to the polymeric backbone or a combination of both.

Suitable polyamine N-oxides wherein the N-0 group forms part of the polymerisable unit comprise polyamine N-oxides wherein R is selected from aliphatic, aromatic, alicyclic or heterocyclic groups. One class of said polyamine N-oxides comprises the group of polyamine N-oxides wherein the nitrogen of the N-0 group forms part of the R-group. Preferred polyamine N-oxides are those wherein R is a heterocyclic group such as pyrridine, pyrrole, imidazole, pyrrolidine, piperidine, quinoline, acridine and derivatives thereof. Other suitable polyamine N-oxides are the polyamine oxides whereto the N-0 group is attached to the polymerisable unit. A preferred class of these polyamine N-oxides comprises the polyamine N-oxides having the general formula (I) wherein R is an aromatic, heterocyclic or alicyclic groups wherein the nitrogen of the N-0 functional group is part of said R group. Examples of these classes are polyamine oxides wherein R is a heterocyclic compound such as pyrridine, pyrrole, imidazole and derivatives thereof.

The polyamine N-oxides can be obtained in almost any degree of polymerisation. The degree of polymerisation is not critical provided the material has the desired water-solubility and dye-suspending power. Typically, the average molecular weight is within the range of 500 to 1000,000.

b Copolymers of N-vinylpyrrolidone and N-vinylimidazole

Suitable herein are coploymers of N-vinylimidazole and N- vinylpyrrolidone having an average molecular weight range of from 5,000 to 50,000. The preferred copolymers have a molar ratio of N- vinylimidazole to N-vinylpyrrolidone from 1 to 0.2.

c) Polyvinylpyrrolidone

The detergent compositions herein may also utilize polyvinylpyrrolidone ("PVP") having an average molecular weight of from 2,500 to 400,000. Suitable polyvinylpyrrolidones are commercially available from ISP Coφoration, New York, NY and Montreal, Canada under the product names PVP K-15 (viscosity molecular weight of 10,000), PVP K-30 (average molecular weight of 40,000), PVP K-60 (average molecular weight of 160,000), and PVP K-90 (average molecular weight of 360,000). PVP K-15 is also available from ISP Coφoration. Other suitable polyvinylpyrrolidones which are commercially available from BASF Cooperation include Sokalan HP 165 and Sokalan HP 12. d) Polyvinyloxazolidone

The detergent compositions herein may also utilize polyvinyloxazolidones as polymeric dye transfer inhibiting agents. Said polyvinyloxazolidones have an average molecular weight of from 2,500 to 400,000.

e Polyvinylimidazole

The detergent compositions herein may also utilize polyvinylimidazole as polymeric dye transfer inhibiting agent. Said polyvinylimidazoles preferably have an average molecular weight of from 2,500 to 400,000.

Opticar-brightener

The detergent compositions herein also optionally contain from about 0.005% to 5% by weight of certain types of hydrophilic optical brighteners.

Hydrophilic optical brighteners useful herein include those having the structural formula:

wherein R\ is selected from anilino, N-2-bis-hydroxyethyl and NH-2- hydroxyethyl; R2 is selected from N-2-bis-hydroxyethyl, N-2- hydroxyethyl-N-methylamino, moφhilino, chloro and amino; and M is a salt-forming cation such as sodium or potassium.

When in the above formula, Rj is anilino, R2 is N-2-bis-hydroxyethyl and M is a cation such as sodium, the brightener is 4,4' , ϋis[(4-anilino- 6-(N-2-bis-hydroxyethyl)-s-triazine-2-yl)amino]-2,2'-stilbenedisulfonic acid and disodium salt. This particular brightener species is commercially marketed under the tradename Tinopal-UNPA-GX by Ciba-Geigy Coφoration. Tinopal-UNPA-GX is the preferred hydrophilic optical brightener useful in the detergent compositions herein.

When in the above formula, Rj is anilino, R2 is N-2-hydroxyethyl-N- 2-methylamino and M is a cation such as sodium, the brightener is 4,4'-bis[(4-anilino-6-(N-2-hydroxyethyl-N-methylamino)-s-triazine-2- yl)amino]2,2'-stilbenedisulfonic acid disodium salt. This particular brightener species is commercially marketed under the tradename Tinopal 5BM-GX by Ciba-Geigy Coφoration. When m the above formula, Rj is anilino, R2 is moφhilino and M is a cation such as sodium, the brightener is 4,4'-bis[(4-anilino-6- moφhilino-s-triazine-2-yl)amino]2,2'-stilbenedisulfonic acid, sodium salt. This particular brightener species is commercially marketed under the tradename Tinopal AMS-GX by Ciba Geigy Coφoration.

Cationic fabric softening agents

Cationic fabric softening agents can also be incoφorated into compositions in accordance with the present invention. Suitable cationic fabric softening agents include the water insoluble tertiary amines or dilong chain amide materials as disclosed in GB-A-1 514 276 and EP-B-0 011 340.

Cationic fabric softening agents are typically incoφorated at total levels of from 0.5 % to 15 % by weight, normally from 1 % to 5 % by weight.

Other optional ingredients

Other optional ingredients suitable for inclusion in the compositions of the invention include perfumes, colours and filler salts, with sodium sulfate being a preferred filler salt.

pH of the compositions

The present compositions preferably have a pH measured as a 1 % solution in distilled water of at least 10.0, preferably from 10.0 to 12.5, most preferably from 10.5 to 12.0.

Form of the compositions

The compositions in accordance with the invention can take a variety of physical forms including granular, tablet forms. The compositions are particularly the so-called concentrated granular detergent compositions adapted to be added to a washing machine by means of a dispensing device placed in the machine drum with the soiled fabric load.

The mean particle size of the components of granular compositions in accordance with the invention should preferably be such that no more that 5 % of particles are greater than 1.7mm in diameter and not more than 5% of particles are less than 0.15mm in diameter.

The term mean particle size as defined herein is calculated by sieving a sample of the composition into a number of fractions (typically 5 fractions) on a series of Tyler sieves. The weight fractions thereby obtained are plotted against the aperture size of the sieves. The mean particle size is taken to be the aperture size through which 50 % by weight of the sample would pass.

Density of the detergent composition is measured by means of a simple funnel and cup device consisting of a conical funnel moulded rigidly on a base and provided with a flap valve at its lower extremity to allow the contents of the funnel to be emptied into an axially aligned cylindrical cup disposed below the funnel. The funnel is 130 mm high and has internal diameters of 130 mm and 40 mm at its respective upper and lower extremities. It is mounted so that the lower extremity is 140 mm above the upper surface of the base. The cup has an overall height of 90 mm, an internal height of 87 mm and an internal diameter of 84 mm. Its nominal volume is 500 ml.

To carry out a measurement, the funnel is filled with powder by hand pouring, the flap valve is opened and powder allowed to overfill the cup. The filled cup is removed from the frame and excess powder removed from the cup by passing a straight edged implement eg; a knife, across its upper edge. The filled cup is then weighed and the value obtained for the weight of powder doubled to provide a bulk density in g/litre. Replicate measurements are made as required. Agglomerate particles

Components used herein in granular compositions may be in the form of an agglomerate particle, which may take the form of flakes, prills, marumes, noodles, ribbons, but preferably take the form of granules. The most preferred way to process the particles is by agglomerating powders (e.g. aluminosilicate, carbonate) with high active pastes and to control the particle size of the resultant agglomerates within specified limits. Such a process involves mixing an effective amount of powder with a high active paste in one or more agglomerators such as a pan agglomerator, a Z-blade mixer or more preferably an in-line mixer such as those manufactured by Schugi (Holland) BV, 29 Chroomstraat 8211 AS, Lelystad, Netherlands, and Gebruder Lodige Maschinenbau GmbH, D-4790 Paderborn 1 , Elsenerstrasse 7-9, Postfach 2050, Germany. Most preferably a high shear mixer is used, such as a Lodige CB (Trade Name).

A high active paste comprising from 50% by weight to 95% by weight, preferably 70% by weight to 85% by weight of surfactant is typically used. The paste may be pumped into the agglomerator at a temperature high enough to maintain a pumpable viscosity, but low enough to avoid degradation of the surfactant used. An operating tempera re of the paste of 50°C to 80°C is typical.

Laundry washing method

Machine laundry methods herein typically comprise treating soiled laundry with an aqueous wash solution in a washing machine having dissolved or dispensed therein an effective amount of a machine laundry detergent composition in accord with the invention. By an effective amount of the detergent composition it is meant from 40g to 300g of product dissolved or dispersed in a wash solution of volume from 5 to 65 litres, as are typical product dosages and wash solution volumes commonly employed in conventional machine laundry methods. In a preferred use aspect a dispensing device is employed in the washing method. The dispensing device is charged with the detergent product, and is used to introduce the product directly into the drum of the washing machine before the commencement of the wash cycle. Its volume capacity should be such as to be able to contain sufficient detergent product as would normally be used in the washing method.

Once the washing machine has been loaded with laundry the dispensing device containing the detergent product is placed inside the drum. At the commencement of the wash cycle of the washing machine water is introduced into the drum and the drum periodically rotates. The design of the dispensing device should be such that it permits containment of the dry detergent product but then allows release of this product during the wash cycle in response to its agitation as the drum rotates and also as a result of its contact with the wash water.

To allow for release of the detergent product during the wash the device may possess a number of openings through which the product may pass. Alternatively, the device may be made of a material which is permeable to liquid but impermeable to the solid product, which will allow release of dissolved product. Preferably, the detergent product will be rapidly released at the start of the wash cycle thereby providing transient localised high concentrations of product in the drum of the washing machine at this stage of the wash cycle.

Preferred dispensing devices are reusable and are designed in such a way that container integrity is maintained in both the dry state and during the wash cycle. Especially preferred dispensing devices for use with the composition of the invention have been described in the following patents; GB-B-2, 157, 717, GB-B-2, 157, 718, EP-A- 0201376, EP-A-0288345 and EP-A-0288346. An article by J.Bland published in Manufacturing Chemist, November 1989, pages 41-46 also describes especially preferred dispensing devices for use with granular laundry products which are of a type commonly know as the "granulette" . Another preferred dispensing device for use with the compositions of this invention is disclosed in PCT Patent Application No. W094/11562. Especially preferred dispensing devices are disclosed in European Patent Application Publication Nos. 0343069 & 0343070. The latter Application discloses a device comprising a flexible sheath in the form of a bag extending from a support ring defining an orifice, the orifice being adapted to admit to the bag sufficient product for one washing cycle in a washing process. A portion of the washing medium flows through the orifice into the bag, dissolves the product, and the solution then passes outwardly through the orifice into the washing medium. The support ring is provided with a masking arrangemnt to prevent egress of wetted, undissolved, product, this arrangement typically comprising radially extending walls extending from a central boss in a spoked wheel configuration, or a similar structure in which the walls have a helical form.

Alternatively, the dispensing device may be a flexible container, such as a bag or pouch. The bag may be of fibrous construction coated with a water impermeable protective material so as to retain the contents, such as is disclosed in European published Patent Application No. 0018678. Alternatively it may be formed of a water-insoluble synthetic polymeric material provided with an edge seal or closure designed to rupture in aqueous media as disclosed in European published Patent Application Nos. 0011500, 0011501, 0011502, and 0011968. A convenient form of water frangible closure comprises a water soluble adhesive disposed along and sealing one edge of a pouch formed of a water impermeable polymeric film such as polyethylene or polypropylene.

Packaging for the compositions

Commercially marketed executions of the bleaching compositions can be packaged in any suitable container including those constructed from paper, cardboard, plastic materials and any suitable laminates. A preferred packaging execution is described in European Application No. 94921505.7. Abbreviations used in Examples

In the detergent compositions, the abbreviated component identifications have the following meanings:

LAS Sodium linear C12 alkyl benzene sulfonate Nonionic 45E7 A C 14-15 predominantly linear primary alcohol condensed with an average of 7 moles of ethylene oxide

QAS R₂.N+(CH₃)₃ with R₂ = C12 - C14 STPP Anhydrous sodium tripolyphosphate

Carbonate Anhydrous sodium carbonate with a particle size between 200μm and 900μm

Silicate Amoφhous Sodium Silicate (Siθ2:Na2θ; 2.0 ratio)

Sodium sulfate Anhydrous sodium sulfate

MA/AA Copolymer of 1 :4 maleic/acrylic acid, average molecular weight about 70,000.

CMC Sodium carboxymethyl cellulose

Protease Proteolytic enzyme of activity 4KNPU/g sold by NOVO Industries A/S under the tradename

Savinase

Alcalase Proteolytic enzyme of activity 3AU/g sold by

NOVO Industries A/S Cellulase Cellulytic enzyme of activity 1000 CEVU/g sold by NOVO Industries A/S under the tradename Carezyme

Amylase Amylolytic enzyme of activity 60KNU/g sold by NOVO Industries A/S under the tradename

Termamyl 60T

Lipase Lipolytic enzyme of activity lOOkLU/g sold by NOVO Industries A/S under the tradename

Lipolase

PB1 Anhydrous sodium perborate bleach of nominal formula NaBθ2-H2θ2 TAED Tetraacetylethylenediamine 480N Random copolymer of 3:7 acrylic/methacrylic acid, average molecular weight about 3,500

DTPA(A) Diethylene triamine pentaacetic acid Photoactivated Sulfonated Zinc Phthlocyanine encapsulated in bleach dextrin soluble polymer

SRP Sulfobenzoyl end capped esters with oxyethylene oxy and terephtaloyl backbone

Silicone antifoam Polydimethylsiloxane foam controller with siloxane-oxyalkylene copolymer as dispersing agent with a ratio of said foam controller to said dispersing agent of 10: 1 to 100: 1.

In the following Examples all levels are quoted as % by weight of the composition:

Example 1

Compositions B to D were prepared with accord to the present invention. Composition A is a comparative composition known in the art and X is a nil-sulphate composition.

Example 2

Compositions F to I were prepared with accord to the present invention. Composition E is a comparative composition known in the art and Y represents a nil-sulphate composition.

Example 3

Compositions K and L were prepared with accord to the present invention. Composition J is a comparative composition known in the art and Z represents a nil-sulphate composition.

Measurement of Caking

The compositions prepared by the process of the present invention are less predisposed to caking than other reduced and nil-sulphate compositions previously documented. Caking potential is measured by a standard test procedure for measuring cake strength. In general terms the cake strength test is a measure of the force required to break a detergent composition cake pre-packed at a specific pressure. The 'stickier' the detergent components, the greater the force required to break the cake.

The cake strength measuring equipment consists essentially of a solid perspex cylinder, with a polished surface (diameter 6.35cm, length 15.90cm), a hollow perspex sleeve with a polished inner surface (inner diameter 6.35cm, wall thickness 1.5cm, length 15.25cm), a perspex disc lid (diameter 11.5cm and thickness 0.65cm), a 5 Kg weight and a force gauge.

The sleeve and cylinder, the latter fitted inside the former, are placed vertically on a flat surface. The cylinder/sleeve is filled with detergent composition which has been stored at 35°C for 12 hours. The detergent composition in the cylinder/sleeve is levelled using a straight edged knife and the lid fitted on the top of the detergent. The 5 Kg weight is then placed on the lid, such that the weight provides an even pressure across the surface of the lid. The weight is left to compress the detergent for 2 minutes. After 2 minutes, the weight is removed and the sleeve slid downward, leaving a cake of detergent. The force gauge is then directed to the centre of the lid and the force required to break the cake is noted. The following scale is representative of consumer perception.

Cake Strength / lbs Consumer Perception

0 excellent

1 very good

2 good

3 satisfactory 4/5 poor 6/7 unacceptable Table 1. represents cake strength data produced for the compositions described in Example 2 (compositions E, F, G, H, I and Y)

Table 1.

It can be seen from the data described in table 1 , that the compositions of the present invention have reduced potential for caking.

Claims

What is claimed is:

1. A process for preparing a detergent composition, said process comprising spray drying a slurry of organic and inorganic material wherein the ratio of organic to inorganic material is from 0.34 to 0.64, and said slurry having a moisture content of between 25% and 50% .

2. A process according to Claim 1 wherein the organic to inorganic ratio is from 0.36 to 0.48.

3. A process according to either of Claims 1 or 2 wherein the slurry has a moisture content of between 34 % and 43 % .

4. A process according to any of Claims 1 to 3 wherein air is injected into the slurry of organic and inorganic material.

5. A process according to any of Claims 1 to 4 wherein the organic material is an organic surfactant.

6. A process according to Claim 5 wherein the organic surfactant is an anionic, cationic or amphoteric surfactant.

7. A process according to either of Claims 5 or 6 wherein the organic surfactant is linear alkylbenzene sulphonate.

8. A process according to any of Claims 1 to 7 wherein the inorganic material is selected from the group consisting of phosphate, carbonate, aluminosilicate, crystalline layered silicate, citrate, alkali metal and/or alkali earth metal silicate and sulphate or mixtures thereof.

9. A process according to Claim 8 wherein the ratio of organic to inorganic material is altered by addition or deletion of alkali metal and/or alkali earth metal sulphate.

10. A detergent composition prepared by the process according to any of of Claims 1 to 9.

11. A detergent composition according to Claim 10 having density of less than 599 g/1.

12. A detergent composition according to Claim 10 having density of 400g/l or less.