WO1991009932A1

WO1991009932A1 - Detergent compositions

Info

Publication number: WO1991009932A1
Application number: PCT/EP1990/002123
Authority: WO
Inventors: David Machin; Johannes Cornelis Van De Pas; Mark Eric Pflugfelder; Thomas Taylor
Original assignee: Unilever N.V.; Unilever Plc
Priority date: 1989-12-12
Filing date: 1990-12-10
Publication date: 1991-07-11
Also published as: EP0506700A1; GB8928023D0; AU8004491A; ZA909995B; CA2071517A1; BR9007988A; JPH05502255A

Abstract

A method for the preparation of a granular detergent composition, comprising the manufacture of a base powder by drying a detergent slurry, wherein said detergent slurry comprises a deflocculating polymer. Also provided is a detergent slurry for use in this process and a granular detergent composition comprising a deflocculating polymer.

Description

I

DETERGENT COMPOSITIONS

The present invention relates to detergent compositions and methods for the manufacture thereof. In particular the present invention relates to granular detergent compositions and to drying or granulation processes for obtaining these compositions.

In the manufacture of detergent compositions it is customary to make a fluid composition (a so-called detergent slurry) containing one or more of the main ingredients of the composition, whereafter the slurry is subjected to a drying step, generally a spray- drying step, to produce a granular material. For obtaining the final detergent composition this granular base material may be further processed, for example it may be further densified and/or agglomerated and/or other active materials may be sprayed onto the powder and/or other powdered ingredients may be mixed with the base powder.

In the manufacture of granular detergent compositions it is preferred that slurries to be dried are of a sufficiently low viscosity to allow the pumping and/or spraying of the slurry in conventional drying equipment. For obtaining a satisfactory slurry viscosity it is customary that slurries for use in the preparation of granular detergent compositions contain relatively high levels of water. For example US

4,261,793 (Procter and Gamble) discloses detergent slurries containing 38 wt % or more of moisture, GB 1,189,543 (Colgate) discloses detergent slurries containing about 29 wt % of water.

For reducing the costs involved with the drying step, it is preferred that the moisture content of the slurry is decreased. This moisture reduction of the slurry may also be advantageous to provide less

SUBSTITUTESHEET porous particles after drying. A problem in decreasing the moisture content of slurries for use in the preparation of granular detergent products is the possible increase of viscosity of the slurry.

For reducing the costs involved with the drying step, it is also sometimes preferred to reduce the temperature to which the detergent slurry is pre¬ heated. Hitherto it is however believed that this preheating step is necessary for increasing the pumpability and/or preventing crystallisation of ingredients in the time between slurry preparation and drying.

It has now been found that the one or more of the above mentioned problems may be solved and the viscosity of slurries may advantageously be reduced and/or the water level of the slurries may be reduced without viscosity problems and/or pre-heating of the slurry may -partially- be omitted, if a deflocculating polymer is included in the slurry. Also it has been found that the presence of deflocculating polymers in granular detergent compositions may improve the dispersability of these compositions. Other possible advantages of using deflocculating polymers are an increase of anti-redeposition properties and/or increased building properties.

Accordingly, a first embodiment of the present invention relates to a method for the preparation of a granular detergent composition, comprising the manufacture of a base powder by drying a detergent slurry, wherein said detergent slurry comprises a deflocculating polymer.

A second embodiment of the present invention relates to a granular detergent composition comprising a deflocculating polymer.

SUBSTITUTESHEET The deflocculating polymer

It has been proposed in our non-prepublished patent applications EP 89201530.6, GB 8924479.2, GB 8924478.4 and GB 8924477.6 to use deflocculating polymers in liquid detergent compositions of the lamellar droplet type. It has now been found that deflocculating polymers can also been used for viscosity reduction of detergent slurries and/or for increasing the dispersability of granular detergent compositions.

Suitable deflocculating polymers for use in accordance with the present invention are for instance described in our copending European patent application 89201530.6. Polymers as described therein have a hydrophilic backbone and at least one hydrophobic side chain.

Generally the hydrophilic backbone of the polymer is predominantly linear (the main chain of the backbone constitutes at least 50 %, preferably more than 75 %, most preferred more than 90% by weight of the backbone) , suitable monomer constituents of the hydrophilic backbone are for example unsaturated C^.g acids, ethers, alcohols, aldehydes, ketones or esters, sugar units, alkoxy units, maleic anhydride and saturated polyalcohols such as glycerol. Examples of suitable monomer units are acrylic acid, methacrylic acid, maleic acid, vinyl acetic acid, glucosides, ethylene oxide and glycerol. The hydrophilic backbone made from the backbone constituents in the absence of hydrophobic side-groups is relatively water-soluble at ambient temperature and a pH of between 6.5 and 14.0. Preferably the solubility is more than 1 g/1, more preferred more than 5 g/1 most preferred more than 10 g/1.

Preferably the hydrophobic sidegroups are composed of relatively hydrophobic alkoxy groups for example butylene oxide and/or propylene oxide and/or alkyl or alkenyl chains having from 5 to 24 carbon atoms. The hydrophobic groups may be connected to the hydrophilic backbone via relatively hydrophilic bonds for example a poly ethoxy linkage.

Preferred polymers are of the formula:

wherein:

Q² is a molecular entity of formula (la) :

wherein:

R¹ represents -C0-0-, -0-, -0-C0-, -CH₂-, -CO-NH- or is absent;

R² represents from 1 to 50 independently selected

SUBSTITUTESHEET alkyleneoxy groups preferably ethylene oxide or propylene oxide groups, or is absent, provided that when R³ is absent and R⁴ represents hydrogen or contains no more than 4 carbon atoms, then R² must contain an alkyleneoxy group preferably more than 5 alkyleneoxy groups with at least 3 carbon atoms;

R³ represents a phenylene linkage, or is absent;

R⁴ represents hydrogen or a C₁_₂4 alkyl or C₂_₂₄ alkenyl group, with the proviso that when R² is absent, R⁴ is not hydrogen and when also R³ is absent, then R⁴ must contain at least 5 carbon atoms;

R⁵ represents hydrogen or a group of formula -COOA⁴;

R⁶ represents hydrogen or C--^ alkyl; and

A¹, A², A³ and A⁴ are independently selected from hydrogen, alkali metals, alkaline earth metals, ammonium and amine bases and C-^_₄, or (C₂H₄θ)tH wherein t is from 1-50, and wherein the monomer units may be in random order.

Q¹ is a multifunctional monomer, allowing the branching of the polymer, wherein the monomers of the polymer may be connected to Q¹ in any direction, in any order, therewith possibly resulting in a branched polymer. Preferably Q¹ is trimethyl propane triacrylate (TMPTA) , methylene bisacrylamide or divinyl glycol.

z and v are 1; n is at least 1; (x + y + p + q + r) : z is from 4 : 1 to 1,000 : 1, preferably from 6 : l to 250 : 1; in which the monomer units may be in random order; and preferably p and q are zero and/or r is zero; most preferably p, q, y and r are zero.

TITUTESHEET R⁷ and R⁸ represent -CH₃ or -H;

R⁹ and R¹⁰ represent substituent groups such as amino, amine, amide, sulphonate, sulphate, phosphonate, phosphate, hydroxy, carboxyl and oxide groups, preferably they are selected from -S0₃Na, -CO-O-C₂H₄- OS0₃Na, -CO-0-NH-C(CH₃)₂-S0₃Na, -CO-NH₂, -0-CO-CH₃, -OH;

Preferably polymers for use at relatively high pH (say 10 or more) are substantially free of hydrolysable groups such as carbonyl groups for increased polymer stability at high pH values. Particularly preferred polymers for use under high pH conditions comprise hydrophilic backbones constituted by acid groups such as acrylic acid and at least one hydrophobic side chain which is constituted of from 5 to 75 relatively water-insoluble alkoxy groups such as propoxy units optionally linked to the hydrophylic backbone via an poly-alkoxy linkage constituted of from 1-10 relatively watersoluble alkoxy groups such as ethoxy units.

Other preferred polymers for use in accordance with the invention are described in our copending British patent applications 8924479.2, 8924478.4 and 8924477.6. Of the polymers described in those patent applications, especially the use of polymers in accordance with GB patent application 8924478.4 is preferred. These polymers are constituted of nonionic monomers and ionic monomers, wherein the ionic monomer is from 0.1 to 50 % by weight of the polymer. Especially preferred polymers of this type are of the formula:

SUBSTITUTE SHEET

wherein: x, z and n are as above;

- R³ and R⁴ represent hydrogen or Cχ_4 alkyl;

- R² represents -C0-0-, -0-, -0-CO-,

-CH₂-, -CO-NH-, or is absent;

- R¹ represents -C₃H₆-N⁺-(CH₃)₃(Cl~) , -C₂H₄-OS0₃-(Na⁺), -S0₃"(Na⁺),

-C₂H₄ N+(CH₃)₂ Cl", -C₂H₄ N⁺ (C₂H₆)₂ Cl", -CH₂ N⁺ (CH₃)₂ Cl", -CH₂ N+ (C₂H₆)₂ Cl" or benzyl-S0 ~ (Na⁺) ;

- R^a is CH , C H4, C3H6 or is absent;

- R*° represents form 1 to 50 independently selected alkylene oxide groups, preferably ethylene oxide groups or is absent;

- R^c represents -OH or -H; and wherein if R²,R^a and ^b are absent, then R^c is not -H.

Other preferred polymers have the formula:

(III)

Wherein: - x = xi + χ₂

- x,z and n are as defined above

- R¹ represents -CH₂0- or -0-;

- R² represents -CH₂COO"Na+ or -C₃H₆ON⁺(CH₃)₃C1~

- R³ and R⁴ represents -OH, CH₂OH, -0(C₃H₆0)_p-H, -CH₂-0(C₃H₆0)_p-H or -OCH₂COO"Na⁺ or

-0-C₃H₆ON⁺(CH₃)₃Cl-

- R⁵ represents -OH, -NH-CO-CH₃ or -0(C₃H₆0)_p-H

- R⁶ represents -OH,-CH₂OH, -CH₂-OCH₃, -0(C₃H₆0)_p-H or -CH₂-0-(C₃H₆0)_p-H - p is from 1 - 10.

Preferably polymers for use in compositions have a molecular weight (as determined as in our co-pending european patent application 89201530.6) of between 500 and 250,000, more preferred from 1,000 to 50,000, especially preferred from 1,500 to 30,000 most preferred from 2,800 to 25,000. Polymers for use in accordance with the invention may for example be prepared by using conventional polymerisation procedures, such as solution SHEET polymerisation or condensation polymerisation; suitable methods are for example described in the above mentioned co-pending european patent application.

It is preferred that the level of deflocculating polymers in the final granular detergent product is from 0.01 to 10 % by weight, more preferred from 0.05 to 8 %, most preferably from 0.1 to 5 % by weight. Since the final granular detergent composition may comprise other materials in addition to the base powder, the level of deflocculating polymers in the base powder may be higher say from 0.02 to 15 %, more preferred from 0.1 to 10.0 %, most preferred from 0.2 to 7.5 %. Generally the level of deflocculating polymers in the detergent slurry is from 0.01 to 10 % by weight of the slurry, more preferred from 0.05 to 7.5 %, most preferred from 0.1 to 5 %.

Suitable viscosity reducing effects may already be obtained by using very low levels of deflocculating polymers in the detergent slurry, for example less than 1 %, or even less than 0.5 % or 0.3 % by weight. The level of deflocculating polymers in the base powder or in the final granular detergent composition may be equally low.

Without being bound by any particular interpretation or theory, the Applicants have hypothesised that the polymers exert their action on the detergent slurries by the following mechanism. Under the conditions (e.g. active level, shear, temperature etc) as present in the time period between slurry making and slurry drying, often the detergent slurry has a structure of lamellar droplets of detergent active materials dispersed in a continuous aqueous phase and/or the detergent slurry comprises solid particles dispersed in the continuous phase.

Lamellar droplets are a particular class of surfactant structures which, inter alia, are already known from a variety of references, e.g. H.A.Barnes, 'Detergents¹, Ch.2. in K.Walters (Ed), 'Rheometry: Industrial Applications', J. Wiley & Sons, Letchworth 1980. The droplets consist of an onion-like configuration of concentric bi-layers of surfactant molecules, between which is trapped water or electrolyte solution (aqueous phase) . Systems in which such droplets are close- packed may suffer from flocculation of the lamellar droplets which may lead to a viscosity increase.

If deflocculating polymers are present in the lamellar droplet detergent slurry the polymers may be situated in or onto the outer bi-layer of the droplets, leaving the hydrophilic backbone or nonionic backbone over the outside of the droplets.

When the hydrophobic side chains or ionic groups are mainly incorporated in or onto the outer bilayer of the droplets, this has the effect of decoupling the inter- and intra-droplet forces i.e. the difference between the forces between individual surfactant molecules in adjacent layers within a particular droplet and those between surfactant molecules in adjacent droplets could become accentuated in that the forces between adjacent droplets are reduced. This will generally result in an decrease in viscosity due to smaller forces between the droplets resulting in greater distances between adjacent droplets.

Without being bound by any particular interpretation or theory, the Applicants have hypothesised that the polymers exert their action on the dispersability of granular detergent compositions by the following mechanism. In analogy with the above described mechanism, the deflocculating polymer may provide, upon contact of the granular detergent compositions with water, for example in the dispenser tray of a washing machine, a viscosity reduction of the aqueous phase surrounding the particles. This is believed to help in preventing the blocking of pores between the particles. The result is an easier particle separation and more ready dispersability.

The better dispersability is especially observed when the detergent composition comprises non-phosporous builder materials, especially zeolite builder materials.

For optimum targetting of the deflocculating polymer to coat particles prone to flocculation, it could sometimes be preferable to add the deflocculating polymers to the granular detergent compositions by methods other than via the detergent slurry. For example the deflocculating polymers may be post-dosed for example by liquid injection, spraying onto the particles or by co-spraying a liquid.

Detergent slurries for use in a method according to the first embodiment of the invention comprise one or more of the main ingredients of the final granular detergent composition. In the context of the present invention main ingredients of granular detergent compositions are detergent active materials, builder materials, bleach materials and electrolyte (non-builder) ingredients.

Preferably slurries for use in a method of the invention comprise a substantial part of the detergent active materials of the final granular detergent composition. Preferably at least 50 % by weight of the detergent active materials of the final composition are included in the slurry, more preferably more than 60 %, most preferably from 70-100%. More preferably the detergent slurry comprises substantial amounts of the detergent active materials in combination with a substantial part of the builder materials. Especially preferably the detergent slurry comprises detergent ^■ active materials in combination with builder materials and electrolyte materials. Most preferably the detergent slurry comprises substantially all ingredients of the final granular detergent composition in their desired weight ratios, except for those ingredients which are advantageously post-dosed. Ingredients which are preferably post-dosed include bleach-ingredients, bleach precursors, enzymes, perfumes and any other temperature sensitive materials.

Unlike the liquid detergent composition as described in the above mentioned non-prepublished patent applications, detergent slurries for use in methods of the invention have no requirement of physical stability. Generally detergent slurries will be physically unstable, that means that they show more than 10 % by volume phase separation upon storage for three weeks at 25 °C. Most detergent slurries will show more than 10 % by volume phase separation upon storage for 1 day at 25 °C.

Accordingly, a third embodiment of the invention relates to a detergent slurry comprising a deflocculating polymer, said slurry being physically unstable.

Preferably the level of detergent active materials in the detergent slurry is from 2 to 70 % by weight of the slurry, more preferred from 5 to 60 %, most preferably from 7 to 50 %.

Preferably the level of builder materials in the detergent slurry is from 2 to 75 % by weight of the slurry, more preferred from 10 to 65 %, most preferably from 20 to 55 % _..

Preferably the level of electrolyte (non-builder) materials in the detergent slurry is from 0 to 40 % by weight of the slurry, more preferred from 1 to 30 %, most preferably from 2 to 15 %.

Preferably the level of water in the detergent slurry is less than 50 % by weight, more preferably from 5-40 % by weight, especially preferred from 8 to 30 % by weight, most preferably from 10 to 25 %.

Preferably the viscosity of the detergent slurry is less than 30,000 mPas at 21 s-1, more preferably from 100 to 7,000 mPas, especially preferably from 300 to 5,000 mPas, most preferably from 500 to 3,000 mPas at ambient temperature.

The detergent slurry may be dried by any conventional method for the drying of detergent slurries. Preferably the detergent slurry is spray-dried, whereby a base powder is formed. The base powder may be further processed for obtaining the final granular detergent compositions. In particular one or more of the following processing steps may be carried out: densification, agglomeratation, other active materials may be sprayed onto the powder and/or other powdered ingredients may be mixed with the base powder.

The final granular detergent composition of the invention will comprise detergent active materials, preferably at a level of from 1 to 70% by weight of the composition, more preferred a level of 5 to 40 % by weight, most preferred from 10 to 35 % by weight.

In the widest definition the detergent-active material in general, may comprise one or more surfactants, and may be selected from anionic, cationic, nonionic, zwitterionic and amphoteric species, and (provided mutually compatible) mixtures thereof. For example, they may be chosen from any of the classes, sub-classes and specific materials described in 'Surface Active Agents' Vol.I, by Schwartz & Perry, Interscience 1949 and •Surface Active Agents' Vol.II by Schwartz, Perry & Berch (Interscience 1958) , in the current edition of "McCutcheon•s Emulsifiers & Detergents" published by the McCutcheon division of Manufacturing Confectioners Company or in 'Tensid-Taschenbuc ' , H.Stache, 2nd Edn. , Carl Hanser Verlag, Mύnchen & Wien, 1981.

Suitable nonionic surfactants include, in particular, the reaction products of compounds having a hydrophobic group and a reactive hydrogen atom, for example aliphatic alcohols, acids, amides or alkyl phenols with alkylene oxides, especially ethylene oxide, either alone or with propylene oxide. Specific nonionic detergent compounds are alkyl (C₆-C₁₈) primary or secondary linear or branched alcohols with ethylene oxide, and products made by condensation of ethylene oxide with the reaction products of propylene oxide and ethylenediamine. Other so-called nonionic detergent compounds include long chain tertiary amine oxides, long-chain tertiary phospine oxides and dialk-yl sulphoxides.

Preferably the level of nonionic surfactants in the final granular composition is more than 1 % by weight of the composition, preferably from 2.0 to 20.0% by weight of the composition.

Compositions of the present invention may contain synthetic anionic surfactant ingredients, which are preferably present in combination with the above mentioned nonionic materials. Suitable anionic surfactants 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 acyl radicals. Examples of suitable synthetic anionic detergent compounds are sodium and potassium alkyl sulphates, especially those obtained by sulphating higher (C₈-C₁₈) alcohols produced, for example, from tallow or coconut oil, sodium and potassium alkyl (Cg-C₂₀) benzene sulphonates, particularly sodium linear secondary alkyl (C₁₀-C₁₅) • benzene sulphonates; sodium alkyl glyceryl ether sulphates, especially those ethers of the higher alcohols derived from tallow or coconut oil and synthetic alcohols derived from petroleum; sodium coconut oil fatty monoglyceride sulphates and sulphonates; sodium and potassium 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 neutralized with sodium hydroxide; sodium and potassium salts of fatty acid amides of methyl taurine; alkane monosulphonates such as those derived by reacting alpha-olefins (C₈-₂₀) with sodium bisulphite and those derived from reacting paraffins with S0₂ and Cl₂ and then hydrolyzing with a base to produce a random sulphonate; and olefin sulphonates, which term is used to describe the material made by reacting olefins, particularly C₁₀-C₂₀ alpha-olefins, with S0₃ and then neutralizing and hydrolyzing the reaction product. The preferred anionic detergent compounds are sodium (^cιι~^ci5) alkyl benzene sulphonates and sodium (Ci₆~^ci_δ) alkyl sulphates.

Generally the level of the above mentioned non-soap anionic surfactant materials in the final granular detergent composition is from 1-40 % by weight of the composition, more preferred 2-30 %, most preferably 3 - 25 % by weigth of the composition.

Preferably the weight ratio of the above mentioned synthetic anionic surfactans to the above mentioned nonionic surfactant materials is from 10 : 1 to 1 : 10, more preferred from 5 : 1 to 1 : 5, most preferred from 3 : 1 to 1 : 3.

It is also possible, and sometimes preferred, to include an alkali metal soap of a mono- or di-carboxylic acid, especially a soap of an acid having from 12 to 18 carbon atoms, for example oleic acid, ricinoleic acid, and fatty acids derived from castor oil, rapeseed oil, groundnut oil,coconut oil, palmkernel oil, alk(en)yl succinates e.g. dodecyl succinate or mixtures thereof. The sodium or potassium soaps of these acids can be used. Preferably the level of soap in the final granular detergent composition of the invention is from 1-40 % by weight of the composition, more preferred from 5-25 %.

Also possible is the use of salting out resistant active materials such as for example described in EP 328 177, especially the use of alkyl poly glycoside surfactants such as for example disclosed in EP 70 074. Also alkyl mono glycosides may be used.

It is preferred that the final granular detergent composition according to the present invention includes detergency builder material, some or all of which may be electrolyte. In this context it should be noted that some detergent active materials such as for example soaps, also have builder properties.

Examples of phosphorous-containing inorganic detergency builders include the water-soluble salts, especially alkali metalpyrophosphates, orthophosphates, polyphosphates and phosphonates. Specific examples of inorganic phosphate builders include sodium and potassium tripolyphosphates, phosphates and hexametaphosphates. Phosphonate sequestrant builders may also be used. Sometimes it is however preferred to minimise the amount of phosphate builders.

Examples of non-phosphorus-containing inorganic detergency builders, when present, include water-soluble alkali metal carbonates, bicarbonates, silicates and crystalline and amorphous aluminosilicates. Specific examples include sodium carbonate (with or without calcite seeds) , potassium carbonate, sodium and potassium bicarbonates, silicates and zeolites.

In the context of inorganic builders, we prefer to include electrolytes which promote the solubility of other electrolytes, for example use of potassium salts to promote the solubility of sodium salts. Thereby, the amount of dissolved electrolyte can be increased considerably (crystal dissolution) as described in UK patent specification GB 1 302 543.

Examples of organic detergency builders, when present, include the alkaline metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates, polyacetyl carboxylates and polyhydroxysulphonates. Specific examples include sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid, nitrilitriacetic acid, oxydisuccinic acid, melitic acid, benzene polycarboxylic acids, CMOS, tartrate mono succinate, tartrate di succinate and citric acid. Citric acid or salts thereof are preferred builder materials for use in compositions of the invention.

Preferably the level of non-soap builder material is from 5-75 % by weight of the composition, more preferred from 10 to 35 % by weight of the composition. For increased dispersability it is preferred that the builder material comprises non-phosphorous builder materials, more preferably all builder materials are non-phosphorous, most preferably zeolite builders are used.

Suitable electrolyte (non-builder) materials for use in compositions of the present invention include alkali (earth) metal sulphates and -halides such as sodium sulphate, sodium chloride, potassium sulphate and potassium chloride. The level of electrolyte (non- builder) materials in the final granular detergent composition is preferably 0-40 wt %, more preferably 0-30%, most preferably 0-20 %. Especially for producing granular detergent compositions having a relatively high bulk density, it is preferred to minimise the amount of electrolyte (non-builder) materials, especially preferably the level of electrolyte (non-builder) materials in these compositions is 0-5 %.

Suitable bleaches are for example peroxy-bleaches such as perborates, precarbonates and peracids. These bleach materials are advantageously used in combination with one or more bleach stabilising ingredients such as TAED. Preferably the bleach materials are post-dosed to the base powder, preferably the bleach materials are dry- mixed with the base powder to form the final granular detergent composition. The level of bleach materials in the final granular composition is preferably from 0-30 wt %, more preferably 0-20 %, most preferably 5-15 %.

Apart from the ingredients already mentioned, a number of optional ingredients may also be present, for example lather boosters such as alkanolamides, particularly the monoethanolamides derived from palm kernel fatty acids and coconut fatty acids, lather depressants, and, usually present in very minor amounts, fluorescent agents, perfumes, enzymes such as proteases, cellulases, amylases and Upases (including Lipolase (Trade Mark) ex Novo) , anti-redeposition agents, germicides and colourants.

SUBSTITUTESHEET Example I

A high bulk density detergent powder of the formulation as indicated in Table I was impregnated with a deflocculating polymer by spraying an aqueous (33 %) solution of polymer onto the powder, followed by drying the coated product to the original Nominal Moisture content. The dispensing of the products was tested by using a poor dispensing rig (AFG Phillips) a rotameter and pressure control meter and Wirral water as follow: 100 g of product was dosed and Wirral water of 10 °C was fed through the- rig at a .flowrate of 5 litres/minute (0.5psi) for 1 minute. The excess water in the rig was carefully removed and the weight of the remaining wet residue was measured. The dispensing residue is the weight of the weight residue as a percentage of the starting material.

Table I Ingredient (wt pts) NaLAS¹) 25

Nonionic²) 2

Soap³) 1

Zeolite⁴) 35

Water 10 Sodium Carbonate 15

Sodium sulphate 1.8

Sokalan CP5 1

Fluorescer 0.2

Sodium silicate⁵) 4 SCMS 0.9

-¹-) C(12-13) linear alkyl benzene sulphonate

²) Synperonic A7

³) Hardened tallow soap ⁴) Wessalith P

⁵) Alkaline silicate Na₂0 2Si0₂

The following results were obtained (avarage % of 4 measurements: SUBSTITUTE SHEET 20

% polymer-^-) Dispenser residue ( wt %.

None 59

2 50 4 9

⁶⁾ polymer All of EP 346 995

These results clearly indicate that a significant increase in dispensing properties can be obtained when a deflocculating polymer is incorporated in a granular detergent composition. It- is believed that similar results can be obtained by incorporating the deflocculating polymer in the slurry mixture.

SUBSTITUTESHEET Example II

The following detergent slurries were made by mixing the ingredients into water in the order listed.

Ingredient (parts by weight )

Na as¹) 6

Nonionic²⁾ 2.75

Hardened Tallow soap 1.65 Zeolite³) 24 sodium citrate 4 alkaline silicate 0.5

Sodium carbonate 15

Deflocculating polymer⁴) 0 or 1 water var

**^•) C(12-13) linear alkyl benzene sulphonate

²) Synperonic A7

³) Wessalith P ⁴⁾ polymer All of EP 346 995

The viscosity of the slurries was measured at 80°C and 25 °C at 21 s"^*1. The following results were obtained:

These results indicate that the viscosity of detergent slurries can significantly be reduced by incorporating into the slurry a deflocculating polymer. These results also show that *the incorporation of deflocculating polymers into detergent slurries allows for the reduction of the water content of the slurries without negative effects on slurry viscosity.

Claims

3.1CLAIMS

1. A method for the preparation of a granular detergent composition, comprising the manufacture of a base powder by drying a detergent slurry, wherein said detergent slurry comprises a deflocculating polymer.

2. A detergent slurry for use in a method in accordance with claim 1, comprising a deflocculating polymer, said detergent slurry being physically unstable.

3. A detergent slurry according to claim 2 , comprising from 2-70 % by weight of detergent active materials.

4. A detergent slurry according to one or more of the claims 2-3, comprising from 2-75 % by weight of builder materials.

5. A detergent slurry according to one or more of the claims 2-4, comprising less than 50 % by weight of water.

6. A granular detergent composition comprising a deflocculating polymer.

7. A granular detergent composition according to claim 6, comprising from 0.01 to 10 % by weight of deflocculating polymers, 1 to 70 % by weight of detergent active materials, 1 to 75 % by weight of non-soap builder materials, 0 to 40 % by weight of electrolyte (non-building) materials and 0 to 30 % by weight of bleach materials.

8. Method, slurry or composition according to one or more of the preceding claims, wherein the deflocculating polymer is of the formula I, II, III