WO2012140421A1

WO2012140421A1 - Novel composite

Info

Publication number: WO2012140421A1
Application number: PCT/GB2012/050797
Authority: WO
Inventors: Victoria BURKITT; Paul John Duffield; Philip Smith; John WASONGA
Original assignee: Reckitt and Colman Overseas Ltd
Current assignee: Reckitt and Colman Overseas Ltd
Priority date: 2011-04-15
Filing date: 2012-04-12
Publication date: 2012-10-18
Anticipated expiration: 2013-10-15
Also published as: GB201106377D0

Abstract

The present invention relates to a detergent formulation comprising a novel composite com- prising one or more core units having an ionic strength-responsive hydroxyl-functional vinylic co-polymeric coating, to a process for the preparation of such a composite, to formulations comprising the same and their use in a variety of industrial applications.

Description

NOVEL COMPOSITE

The present invention relates to an ADW (Automatic Dishwasing) composition comprising a novel composite comprising one or more core units, each core unit comprising an ionic strength-responsive hydroxyl-functional vinylic co-polymeric coating, to a process for the preparation of such a composite, to formulations comprising the same and their use in a variety of industrial applications.

By way of example, the composites of the invention may be employed in solid and liquid cleaning formulations, including bleach containing compositions.

Peroxy acid bleaching agents are employed in a variety of cleaning formulations including laundry and dishwasher cleaning compositions. Such compositions typically comprise, in addition to a bleaching agent, a number of other active and non-active components such as surfactants, enzymes and mixtures thereof. The compositions may be in liquid or solid form.

The inclusion of bleaching agents such as peroxy acids in the same composition with enzymes, although desirable from a cleaning perspective, is problematic since these species tend to react with one another resulting in the loss of active oxygen from the bleaching agent and denaturing of the enzyme.

This incompatibility problem has previously been addressed by formulating and packaging the bleaching agent and the enzyme in such a way that the two components are separated (so- called two chamber products) and only mixed either upon dispensing or upon dissolution of a protective pouch, for example as used in the commercially available products Fairy Platinum (Proctor & Gamble, Cincinnati, USA) and Finish Quantum (Reckitt Benckiser, Hull, UK) dishwasher tablets. Although such products have the capability to act upon both bleachable and enzymatically degradable stains, this is only achieved with significant additional manufacturing and packaging costs compared to single chamber products. Packaging methods of this type place many practical constraints on total product design; limiting freedom in active agent selection and the need to incorporate active agents into specific compartments.

It would be highly desirable to provide a single chamber product capable of housing two or more otherwise incompatible active agents such as bleaching agent and an enzyme, whilst maintaining or improving the properties possessed by the product, such as providing enhanced cleaning properties.

The coating and encapsulation of detergent components with various inorganic and organic materials has been documented in the art. For example, WO 94/15010 (The Proctor & Gamble Company) discloses a solid peroxyacid bleach precursor composition in which particles of per- oxyacid bleach precursor are coated with a water-soluble acid polymer, defined on the basis that a 1 % solution of the polymer has a pH of less than 7.

WO 94/03568 (The Proctor & Gamble Company) discloses a granular laundry detergent composition having a bulk density of at least 650 g/l, which comprises discrete particles comprising from 25-60 % by weight of anionic surfactant, inorganic perhydrate bleach and a peroxyacid bleach precursor, wherein the peroxyacid bleach precursor is coated with a water soluble acidic polymer.

US 6,225,276 (Henkel Kommanditgesellschaft auf Aktien) discloses a solid particulate detergent composition comprising a coated bleaching agent that dissolves in water irrespective of pH, a bleach activator coated with a polymeric acid that only dissolves at pH values above 8, and an acidifying agent.

US 5,972,506 (BASF Aktiengesellschaft) discloses microcapsules containing bleaching agents. The microcapsules are obtained by polymerizing a mixture of monomers in the oil phase of a stable oil-in-water emulsion in the presence of free radical polymerization initiators. WO 97/14780 (Unilever NV) discloses an encapsulated bleach particle comprising a coating including a gelled polymer material, and a core material which is selected from a peroxygen bleach compound, a bleach catalyst and a bleach precursor. The gelled polymer has a molecular structure that is partially or fully cross-linked, such as for example, agar, alginate, carra- geenan, casein, gellan gum, gelatine, pectin, whey proteins, egg protein gels and the like. WO 98/16621 (Warwick International Group Ltd) discloses a process for encapsulating a solid detergent component from an oil-in-water emulsion by forming a polymer film at the oil/water interface by condensation polymerisation. Suitable polymer films include polyamide, polyester, polysulphonamide, polyurea and polyurethane.

WO 98/00515 (The Proctor & Gamble Company) discloses non-aqueous, particulate contain- ing liquid laundry cleaning compositions which are in the form of a suspension of particulate material comprising peroxygen bleaching agents and coated peroxygen bleach activators. The coating material is soluble in water, but insoluble in non-aqueous liquids, and is selected from water soluble citrates, sulfates, carbonates, silicates, halides and chromates.

WO 93/24604 (BP Chemicals Ltd) discloses an encapsulated active substrate comprising a bleach and/or a bleach activator releasably encapsulated in a coating of an alkali metal carbonate or bicarbonate and an outer encapsulating coating of a metal salt of an inorganic salt.

US 6,107,266 (Clariant GmbH) discloses a process for producing coated bleach activating granules in which bleach activator base granules are coated with a coating substrate and are simultaneously and/or subsequently thermally conditioned. The coating substance is selected from C8-C31 fatty acids, C8-C31 fatty alcohols, polyalkylene glycols, non-ionic surfactants and anionic surfactants.

According to a first aspect of the present invention there is provided an ADW detergent formulation comprising a composite comprising one or more core units, each core unit comprising an ionic strength-responsive hydroxyl-functional vinylic copolymeric coating. The formulation is for use as an automatic dishwashing formulation, and/or a dishwasher additive formulation.

Such composites may be placed in liquid and solid product environments, possessing high ionic strength and low or no solvent activity, in which the polymeric coating is indefinitely stable. When the liquid and solid products are dispersed or diluted in water, to realise conditions of lowered ionic strength and higher solvent activity, the protective polymeric coating is compromised, by dissolution, dissolving, rupturing or swelling, and the core material released into the surrounding environment. The novel composites of the present invention are of potential value to numerous consumer and industrial products as further detailed herein.

The composite of the invention comprises one or more core units. The core unit may be in solid or liquid form, and may comprise single discrete particles, agglomerated particles, matrix particles and/or spheronised compositions.

The core unit may comprise an active agent. Examples of suitable active agents include anti- foaming agents, anti-redeposition aids, anti-scale ingredients, biocides, biostats, bleaches (particularly peroxy acids), bleach activators, bleach catalysts, corrosion inhibitors, enzymes, dyes, food additives, fragrances, glass protectors, optical brighteners, antimicrobial agents, perfumes, rinse aids, spot and film control agents.

In one embodiment of the invention the active agent is a bleaching agent. As used herein the term "bleaching agent" means a liquid or solid chemical compound that may be used to whiten or brighten various substrates and/ or remove soil from them. In a preferred embodiment, the bleaching agent is a peroxy acid as defined in formula (1 ) above. More preferably, the peroxy acid bleaching agent is a phthalimido peroxy alkanoic acid bleaching agent as defined in formula (2) above. Most preferably, the peroxy acid bleaching agent is phthalimido peroxy hexa- noic acid (PAP) or a derivative thereof, or a percarbonate or a perborate.. In an alternative embodiment of the invention, the active agent is an anti-foaming agent.

Particulate cores comprising an active agent may be formed by agglomeration, granulation, spheronisation and other techniques known in the art.

According to a preferred embodiment of present invention one or more core units comprising an active agent are coated with an ionic strength-responsive hydroxyl-functional vinylic co- polymer to form a composite. This protective coating enables the core unit(s) comprising the active agent(s) to be co-formulated with one or more other active agents with which it would otherwise be incompatible.

The following ingredients may be present in the formulation either in the composite or the reminder of the formulation or both. Generally the formulation comprises a bleach activator. The bleach activator is possibly in particulate form.

The formulation may contain phosphate or more preferably the formulation may be phostphate free.

Where the bleach activator is in particulate form generally it has a particle size of 0.0001 to 2mm, e.g. such as 1 mm.

Preferably the bleach activator is selected from tetraacetylethylendiamine (TAED), acetylated triazine derivatives, in particular 1 ,5-Diacetyl-2,4-dioxohexahydro-1 ,3,5-triazine (DADHT), ac- etylated glycoluriles, in particular Tetraacetylglycolurile (TAGU), acylimides, in particular n- nonanoylsuccinimide (NOSI), acetylated phenolsulfonates, in particular n-nonanoyloxi or n- lauroyloxibenzolsulfonate (NOBS and/or PRAISE), acetylated phenol carbonic acids, in particular nonanoyloxi or decanoyloxibenzoesaeure (NOBA and/or DOBA), carbonic acid anhydrides, acetylated sugar derivatives, in particular pentaacetylglucose (PAG), pentaacetylfructose, tetraacetylxylose and octaacetyllactose as well as acetylated N-alkylated glucamine and glu- conolactone, and/or N- acetylated lactams, for example N-Benzoylcaprolactam. Hydrophilically substituted ecyl acetals and ecyl lactams are likewise preferentially used. Particularly preferential bleach activators are TAED and DOBA.

Bleaching catalysts may be present. Preferred examples include complexes of manganese, iron, cobalt, ruthenium, molybdenum, titanium or vanadium.

When using metal salts in particular manganese salts are in the oxidation state +2 or +3 pref- erentially, for example manganese halides, whereby the chloride is preferential. Manganese sulfate, manganese salts of organic acids such as manganese acetates, acetylacetonate, oxalates as well as manganese nitrates are suitable.

Metal complex with macromolecular ligands may be used such as1 ,4,7-Trimethyl-1 ,4,7- triazacyclononane (me-TACN), 1 ,4,7-Triazacyclononane (TACN), 1 ,5,9-Trimethyl-1 ,5,9- triazacyclododecane (me-TACD), 2-Methyl-1 ,4,7 trimethyl-1 ,4,7-triazacyclononane (Me- MeTACN) and/or 2-Methyl-1 ,4,7 triazacyclononane (Me/TACN) or ligands such as 1 ,2-bis (4,7- Dimethyl 1 ,4,7-triazacyclonono-i-yl) ethane (Me4-DTNE). The bleaching agent is usually a source of active oxygen, e.g. urea / hydrogen peroxide. The bleaching agent may be based on alternative chemistry, e.g. chlorine based bleaching agents, such as hypochlorite bleaches.

Some bleaching agents, such as phthalimido-peroxy-hexanoic-acid (PAP) per-salts such as; perborate, percarbonate, persulphate; are substantially insoluble in water (e.g. having a solubility of less than 0.6g/litre of demineralised water at 25°C. .

Where the bleaching agent is in particulate form generally it has a particle size of 0.0001 to 2mm, e.g. such as 1 mm.

Examples of bleaches that may be used are oxygen bleaches. Peroxygen bleaching actives are: perborates, peroxides, peroxyhydrates, persulfates. A preferred compound is sodium percarbonate and especially the coated grades that have better stability. The percarbonate can be coated with silicates, borates, waxes, sodium sulfate, sodium carbonate and surfactants solid at room temperature.

Optionally, the compositions may additionally comprise from 0.01 to 30 %wt, preferably from 2 to 20 %wt of bleach precursors. Suitable bleach precursors are peracid precursors, i.e. compounds that upon reaction with hydrogen peroxide product peroxyacids. Examples of peracid precursors suitable for use can be found among the classes of anhydrides, amides, imides and esters such as acetyl triethyl citrate (ATC), tetra acetyl ethylene diamine (TAED), succinic or maleic anhydrides.

When a surfactant is present in the composition, it may be present in an amount of, for example, from 0.01 to 50 %wt, ideally 0.1 to 30 %wt and preferably 0.5 to 10 %wt.

Suitable surfactants that may be employed include anionic or nonionic surfactants or mixture thereof. The nonionic surfactant is preferably a surfactant having a formula RO(CH2CH₂0)nH wherein R is a mixture of linear, even carbon-number hydrocarbon chains ranging from Ci2H₂5 to Ci₆H₃₃ and n represents the number of repeating units and is a number of from about 1 to about 12. Examples of other non-ionic surfactants include higher aliphatic primary alcohol containing about twelve to about 16 carbon atoms which are condensed with about three to thirteen moles of ethylene oxide per mole of alcohol (i.e. equivalents).

Other examples of nonionic surfactants include primary alcohol ethoxylates (available under the Neodol tradename from Shell Co.), such as Cn alkanol condensed with 9 equivalents of ethylene oxide (Neodol 1-9), C12-13 alkanol condensed with 6.5 equivalents ethylene oxide (Neodol 23-6.5), C12-13 alkanol with 9 equivalents of ethylene oxide (Neodol 23-9), C12-15 alkanol condensed with 7 or 3 equivalents ethylene oxide (Neodol 25-7 or Neodol 25-3), C14-15 alkanol condensed with 13 equivalents ethylene oxide (Neodol 45-13), Cg-n linear ethoxylated alcohol, averaging 2.5 moles of ethylene oxide per mole of alcohol (Neodol 91-2.5), and the like.

Other examples of nonionic surfactants suitable for use include ethylene oxide condensate products of secondary aliphatic alcohols containing 1 1 to 18 carbon atoms in a straight or branched chain configuration condensed with 5 to 30 equivalents of ethylene oxide. Examples of commercially available non-ionic detergents of the foregoing type are Cn-i₅ secondary alka- nol condensed with either 9 equivalents of ethylene oxide (Tergitol 15-S-9) or 12 equivalents of ethylene oxide (Tergitol 15-S-12) marketed by Union Carbide, a subsidiary of Dow Chemical. Octylphenoxy polyethoxyethanol type nonionic surfactants, for example, Triton X-100, as well as amine oxides can also be used as a nonionic surfactant.

Other examples of linear primary alcohol ethoxylates are available under the Tomadol tradename such as, for example, Tomadol 1-7, a Cn linear primary alcohol ethoxylate with 7 equiva- lents EO; Tomadol 25-7, a C12-15 linear primary alcohol ethoxylate with 7 equivalents EO; Tomadol 45-7, a C14-15 linear primary alcohol ethoxylate with 7 equivalents EO; and Tomadol 91-6, a C9-11 linear alcohol ethoxylate with 6 equivalents EO.

Other nonionic surfactants are amine oxides, alkyl amide oxide surfactants.

Preferred anionic surfactants are frequently provided as alkali metal salts, ammonium salts, amine salts, aminoalcohol salts or magnesium salts. Contemplated as useful are one or more sulfate or sulfonate compounds including: alkyl benzene sulfates, alkyl sulfates, alkyl ether sulfates, alkylamidoether sulfates, alkylaryl polyether sulfates, monoglyceride sulfates, alkylsul- fonates, alkylamide sulfonates, alkylarylsulfonates, olefinsulfonates, paraffin sulfonates, alkyl sulfosuccinates, alkyl ether sulfosuccinates, alkylamide sulfosuccinates, alkyl sulfosuccina- mate, alkyl sulfoacetates, alkyl phosphates, alkyl ether phosphates, acyl sarconsinates, acyl isethionates, and N-acyl taurates. Generally, the alkyl or acyl radical in these various compounds comprise a carbon chain containing 12 to 20 carbon atoms.

Other surfactants which may be used are alkyl naphthalene sulfonates and oleoyl sarcosinates and mixtures thereof.

Any suitable soil catcher may be employed. Unlike detergents or surfactants, which simply aid in the removal of soils from surfaces, the soil catcher actively binds to the soil allowing it to be removed from the surface of the laundry. Once bound, the soil is less likely to be able to rede- posit onto the surface of the laundry. Preferred soil catchers have a high affinity to both oily and water-soluble soil. Preferably, the soil catcher is a mixture of two or more soil catchers, each soil catcher may have a different affinity for different soils. Preferred soil catchers for oily soils have a non polar structure with high absorption capability. Preferred water based soil catchers are generally charged and have a high surface area in order to attract the soil by electrostatic charge and collect it.

Suitable soil catchers include polymers, such as acrylic polymers, polyesters and polyvinylpyr- rolidone (PVP). The polymers may be crosslinked, examples of which include crosslinked acrylic polymers and crosslinked PVP. Super absorbing polymers are mainly acrylic polymers and they are useful for the scope of this patent.

Other important polymers are ethylidene norbene polymers, ethylidene norbene/ethylene co- polymers, ethylidene norbene/propylene/ethylidene ter-polymers. Inorganic materials may also be employed. Examples include zeolites, talc, bentonites and active carbon. The latter may be used to absorb and/or degrade coloured parts of stain and/or absorb odours. Alginates, carrageneans and chitosan may also be used. Preferred water insoluble agents are selected from at least one of acrylic polymer, polyester, polyvinylpyrrolidone (PVP), silica, silicate, zeo- lite, talc, bentonites, active carbon, alginates, carrageneans, ethylidene mor- bene/propylene/ethylidene ter-polymers and chitosan in the manufacture of a detergent composition as an active agent for binding soil. Preferably the detergent composition is a laundry cleaning composition or stain-removing composition. Preferred examples of water-insoluble soil catcher compounds comprise a solid cross-linked polyvinyl N-oxide, or chitosan product or ethylidene norbene/propylene/ethylidene ter-polymers or blend of the same, as discussed more fully hereafter.

Water soluble polymeric soil catcher agents that are suitable to be bound to insoluble carriers, or to be made insoluble via cross-linking are those polymers known in the art to inhibit the transfer of dyes from coloured fabrics onto fabrics washed therewith. These polymers have the ability to complex or adsorb the fugitive dyes washed out of dyed fabrics before the dyes have the opportunity to become attached to other articles in the wash. Especially suitable polymeric soil catcher agents are polyamine N-oxide polymers, polymers and copolymers of N- vinylpyrrolidone and N-vinylimidazole, vinyloxazolidones, vinylpyridine, vinylpyridine N-oxide, other vinylpyridine derivatives or mixtures thereof.

The soil catcher may be present in the detergent composition in an amount of 0.01 to 100 %wt of the composition, preferably from 1 to 90 %wt, more preferably from 5 to 50 %wt. The composition advantageously additionally comprises cleaning agents selected from the group consisting of, fillers, builders, chelating agents, activators, fragrances, enzymes or a mixture thereof. These active agents are generally water soluble, so dissolve during the wash. Thus the additional active agents are released over a period of time when exposed to water in the laundry washing machine.

Suitable fillers include bicarbonates and carbonates of metals, such as alkali metals and alkaline earth metals. Examples include sodium carbonate, sodium bicarbonate, calcium carbonate, calcium bicarbonate, magnesium carbonate, magnesium bicarbonate and sesqui- carbonates of sodium, calcium and/or magnesium. Other examples include metal carboxy glycine and metal glycine carbonate. Chlorides, such as sodium chloride; citrates; and sulfates, such as sodium sulfate, calcium sulfate and magnesium sulfate, may also be employed.

The filler may be present in an amount of 0.1 to 80 %wt, preferably 1 to 60 %wt.

The composition may comprise at least one builder or a combination of them, for example in an amount of from 0.01 to 80%wt, preferably from 0.1 to 50%wt. Builders may be used as chelating agents for metals, as anti-redeposition agents and/or as alkalis. Examples of builders are described below:

- 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 than can pro- duce borate under detergent storage or wash conditions can also be used.

- iminosuccinic acid metal salts.

- polyaspartic acid metal salts.

- ethylene diamino tetra acetic acid and salt forms.

- water-soluble phosphonate and phosphate builders are useful. Examples of phos- phate builders are the alkali metal tripolyphosphates, sodium potassium and ammonium pyrophosphate, sodium and potassium and ammonium pyrophosphate, sodium and potassium or- thophosphate sodium polymeta/phosphate in which the degree of polymerisation ranges from 6 to 21 , and salts of phytic acid. Specific examples of water-soluble phosphate builders are the alkali metal tripolyphosphates, sodium, potassium and ammonium pyrophosphate, sodium, potassium and ammonium pyrophosphate, sodium and potassium orthophosphate, sodium polymeta/phosphate in which the degree of polymerization ranges from 6 to 21 , and salts of phytic acid. Such polymers include polycarboxylates containing two carboxy groups, 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 derivates such as the carboxymethloxysucci- nates described in GB-A-1 ,379,241 , lactoxysuccinates described in GB-A-1 ,389,732, and ami- nosuccinates described in NL-A-7205873, and the oxypolycarboxylate materials such as 2- oxa-1 ,1 ,3-propane tricarboxylates described in GB-A-1 , 387, 447.

Polycarboxylate containing four carboxy groups include oxydisuccinates disclosed in GB-A- 1 ,261 ,829, 1 , 1 ,2,2-ethane tetracarboxylates, 1 ,1 ,3,3-propane tetracarboxylates and 1 ,1 ,2,3- propane tetracarobyxlates. Polycarboxylates containing sulfo substituents include the sulfo- succinate derivatives disclosed in GB-A-1 , 398,421 , GB-A-1 ,398,422 and US-A-3, 936448, and the sulfonated pyrolysed citrates described in GB-A-1 , 439, 000.

Alicylic and heterocyclic polycarboxylates include cyclopentane-cis,cis,cis-tetracarboxylates, cyclopentadienide pentacarboxylates, 2,3,4,5,6-hexane - hexacarboxylates and carboxymethyl derivates of polyhydric alcohols such as sorbitol, mannitol and xylitol. Aromatic polycarboxylates include mellitic acid, pyromellitic acid and the phthalic acid derivatives disclosed in GB-A- 1 ,425,343. Of the above, the preferred polycarboxylates are hydroxycarboxylates containing up to three carboxy groups per molecule, more particularly citrates.

Other preferred non-phosphate builders include MGDA and GLDA. Suitable polymer water-soluble compounds include the water soluble monomeric polycarboxylates, 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 than two carbon atoms, carbonates, bicarbonates, borates, phosphates, and mixtures of any of the foregoing. The carboxylate or polycarboxylate builder can be monomeric 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 derivates such as the carboxymethloxysuccinates described in GB-A-1 ,379,241 , lac- toxysucci nates described in GB-A-1 , 389, 732, and aminosuccinates described in NL-A- 7205873, and the oxypolycarboxylate materials such as 2-oxa-1 ,1 ,3-propane tricarboxylates described in GB-A-1 , 387,447. Polycarboxylate containing four carboxy groups include oxydisuccinates disclosed in GB-A- 1 ,261 ,829, 1 , 1 ,2,2-ethane tetracarboxylates, 1 ,1 ,3,3-propane tetracarboxylates and 1 ,1 ,2,3- propane tetracarobyxlates. Polycarboxylates containing sulfo substituents include the sulfo- succinate derivatives disclosed in GB-A-1 , 398,421 , GB-A-1 ,398,422 and US-A-3, 936448, and the sulfonated pyrolysed citrates described in GB-A-1 , 439, 000.

Alicylic and heterocyclic polycarboxylates include cyclopentane-cis,cis,cis-tetracarboxylates, cyclopentadienide pentacarboxylates, 2,3,4,5,6-hexane - hexacarboxylates and carboxymethyl derivates of polyhydric alcohols such as sorbitol, mannitol and xylitol. Aromatic polycarboxylates include mellitic acid, pyromellitic acid and the phthalic acid derivatives disclosed in GB-A- 1 ,425,343.

Of the above, the preferred polycarboxylates are hydroxycarboxylates containing up to three carboxy groups per molecule, more particularly citrates. More preferred polymers are homopolymers, copolymers and multiple polymers of acrylic, fluorinated acrylic, sulfonated styrene, maleic anhydride, methacrylic, iso-butylene, styrene and ester monomers. Examples of these polymers are Acusol supplied from Rohm & Haas, Syntran supplied from Interpolymer and the Versa and Alcosperse series supplied from Alco Chemical, a National Starch & Chemical Company. Preferred polymers are sulphonated polymers. Examples of these include Acusol 588D, supplied by Dow.

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.

Examples of bicarbonate and carbonate builders are the alkaline earth and the alkali metal carbonates, including sodium and calcium carbonate and sesqui-carbonate and mixtures thereof. Other examples of carbonate type builders are the metal carboxy glycine and metal glycine carbonates.

In the context of the present application it will be appreciated that builders are compounds that sequester metal ions associated with the hardness of water, e.g. calcium and magnesium, whereas chelating agents are compounds that sequester transition metal ions capable of cata- lysing the degradation of oxygen bleach systems. However, certain compounds may have the ability to do perform both functions.

Suitable chelating agents to be used herein include chelating agents selected from the group of phosphonate chelating agents, amino carboxylate chelating agents, polyfunctionally- substituted aromatic chelating agents, and further chelating agents like glycine, salicylic acid, aspartic acid, glutamic acid, malonic acid, or mixtures thereof. Chelating agents when used, are typically present herein in amounts ranging from 0.01 to 50 %wt of the total composition and preferably from 0.05 to 10 %wt. Suitable phosphonate chelating agents to be used herein may include ethydronic acid as well as amino phosphonate compounds, including amino alkylene poly (alkylene phosphonate), alkali metal ethane 1 -hydroxy diphosphonates, nitrilo trimethylene phosphonates, ethylene diamine tetra methylene phosphonates, and diethylene triamine penta methylene phosphonates. The phosphonate compounds may be present either in their acid form or as salts of different cations on some or all of their acid functionalities. Preferred phosphonate chelating agents to be used herein are diethylene triamine penta methylene phosphonates. Such phosphonate chelating agents are commercially available from Monsanto under the trade name DEQUEST TM. Polyfunctionally-substituted aromatic chelating agents may also be useful in the compositions herein. See U.S. patent 3,812,044, issued May 21 , 1974, to Connor et al. Preferred compounds of this type in acid form are dihydroxydisulfobenzenes such as 1 ,2-di hydroxy -3,5- disulfobenzene. A preferred biodegradable chelating agent for use herein is ethylene diamine N,N'-disuccinic acid, or alkali metal, or alkaline earth, ammonium or substituted ammonium salts thereof or mixtures thereof. Ethylenediamine Ν,Ν'-disuccinic acids, especially the (S,S) isomer have been extensively described in US patent 4, 704, 233, November 3, 1987, to Hartman and Perkins. Ethylenediamine Ν,Ν'-disuccinic acid is, for instance, commercially available under the tradename ssEDDS TM from Palmer Research Laboratories.

Suitable amino carboxylates to be used herein include ethylene diamine tetra acetates, diethylene triamine pentaacetates, diethylene triamine pentaacetate (DTPA),N- hy- droxyethylethylenediamine triacetates, nitrilotri-acetates, ethylenediamine tetrapropionates, triethylenetetraaminehexa-acetates, ethanol-diglycines, propylene diamine tetracetic acid (PDTA) and methyl glycine diacetic acid (MGDA), both in their acid form, or in their alkali metal, ammonium, and substituted ammonium salt forms. Particularly suitable amino carboxylates to be used herein are diethylene triamine penta acetic acid, propylene diamine tetracetic acid (PDTA) which is, for instance, commercially available from BASF under the trade name Trilon FS TM and methyl glycine di-acetic acid (MGDA).

The detergent compositions may comprise a solvent. Solvents can be used in amounts from 0.01 to 30 %wt, preferably in amounts of 0.1 to 3 %wt. The solvent constituent may include one or more alcohol, glycol, acetate, ether acetate, glycerol, polyethylene glycol with molecular weights ranging from 200 to 1000, silicones or glycol ethers. Exemplary alcohols useful in the compositions include C2-8 primary and secondary alcohols which may be straight chained or branched, preferably pentanol and hexanol.

Preferred solvents are glycol ethers. Examples include those glycol ethers having the general structure R_a-O-[CH2-CH(R)-(CH2)-0]_n-H, wherein R_a is C1-2₀ alkyl or alkenyl, or a cyclic alkane group of at least 6 carbon atoms, which may be fully or partially unsaturated or aromatic; n is an integer from 1 to 10, preferably from 1 to 5; and each R is selected from H or CH₃. Specific and preferred solvents are selected from propylene glycol methyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, propylene glycol n-propyl ether, ethylene glycol n-butyl ether, diethylene glycol n-butyl ether, diethylene glycol methyl ether, propylene glycol, ethylene glycol, isopropanol, ethanol, methanol, diethylene glycol monoethyl ether acetate, and, especially, propylene glycol phenyl ether, ethylene glycol hexyl ether and diethylene glycol hexyl ether. The composition may, for example, comprise one enzyme or a combination of them, for example in an amount of from 0.01 to 10 %wt, preferably from 0.1 to 2 %wt. Enzymes in granular form are preferred. Examples of suitable enzymes are proteases, modified proteases stable in oxidisable conditions, amylases, lipases and cellulases.

Claims

1. An ADW detergent formulation comprising a composite comprising one or more core units having an ionic strength-responsive hydroxyl-functional vinylic co-polymeric coating.

2. A formulation according to claim 1 wherein the core units are solid.

3. A formulation according to claim 1 wherein the core units are singular discrete particles.

4. A formulation according to claim 1 wherein the core units are agglomerated particles.

5. A composite according to claim 1 wherein the core units are matrix particles.

6. A formulation according to claim 1 wherein the core units are spheronised compositions.

7. A formulation according to claim 6 wherein the spheronised compositions are prepared using a spheronising aid selected from microcrystalline cellulose, carboxymethylcellulose and hyd roxyethy lcel I u lose.

8. A formulation according to claim 6 or claim 7 wherein the spheronised compositions are prepared using a lubricant selected from a block copolymer of ethylene oxide and propylene oxide.

9. A formulation according to any preceding claim wherein the ionic strength-responsive polymer is insoluble at high ionic strengths yet soluble at low ionic strengths.

10. A formulation according any preceding claim wherein the ionic strength-responsive polymer is insoluble under conditions of low water activity yet soluble under conditions of high water activity.

1 1. A formulation according to any preceding claim wherein the core unit(s) comprise from 10% to 90% of the total composite mass.

12. A formulation according to any preceding claim wherein the ionic strength-responsive polymer coating comprises from 10% to 90% of the total composite mass.

13. A formulation according to any preceding claim wherein the ionic strength-responsive polymer is selected from partially hydrolysed polyvinyl acetate, fully hydrolysed polyvinyl acetate, silanolate modified hydrolysed polyvinyl acetate, ketoester modified hydrolysed polyvinyl acetate, carboxyl modified hydrolysed polyvinyl acetate, poly(hydroxyethyl-methyacrylate), poly(AMPS-hydroxyethylmethacrylate) and ethylene vinyl alcohol copolymer.

14. A formulation according to any preceding claim wherein the ionic strength-responsive polymer comprises a polyvinyl acetate having a 4% w/w solution viscosity (20.0oC) of 15 to 30mPas and a degree of hydrolysis of 90% to 100%.

15. A formulation according to any preceding claim wherein the ionic strength-responsive polymer comprises a modified polyvinyl acetate.

16. A formulation according to any preceding claim wherein the ionic strength-responsive polymer comprises an acrylic copolymer formed from a mixture of monomers selected from 2- acrylamido-2-methylpropane sulphonic acid, methylmethacrylate, hydroxyethylacrylate, hy- droxyethylmethacrulate, ethylmethacrylate and butylmethacrylate.

17. A formulation according to any preceding claim wherein the ionic strength-responsive polymer comprises an ethylene vinyl alcohol copolymer.

18. A formulation according to any preceding claim wherein the core units comprise one or more active agents.

19. A formulation according to claim 18 wherein the active agent comprises a solid.

20. A formulation according to claim 18 wherein the active agent comprises a liquid adsorbed onto an inert solid.

21. A formulation according to any one of claims 18 to 20 wherein the active agent comprises from 1.0% to 100.0% of the core unit(s).

22. A formulation according to any one of claims 18 to 21 wherein the active agent comprises an anti-foam, an anti-redeposition aid, an anti-scale ingredient, a corrosion inhibitor, an antimicrobial agent, an enzyme (e.g. a n amylase, cellulase, lipase or protease, a bleach, a bleach activator, a bleach catalyst, a glass protector, a machine cleaner, an optical brightener, a rinse aid, a dye, a fragrance or a mixture thereof.

23. A formulation according to claim 22 wherein the bleach comprises a peroxy acid.

24. A formulation according to claim 23 wherein the peroxy acid comprises 6- phthalimidoperoxyhexanoic acid or sodium percarbonate.

25. A process for preparing a composite in the formulation according to claim 1 , which process comprises applying an ionic strength-responsive polymer coating to the surface of one or more core units.

26. A process according to claim 25, which process comprises applying the ionic strength responsive polymer coating to the surface of one or more core units by fluid bed coating, pan coating.

27. A process for preparing one or more core units according to claim 1 , which process comprises agglomeration, granulation and spheronisation.