NZ298600A

NZ298600A - Granular detergents containing deflocculating polymers

Info

Publication number: NZ298600A
Application number: NZ298600A
Authority: NZ
Inventors: Elliott M Scherr; Stephen T Repinec
Original assignee: Colgate Palmolive Co
Priority date: 1994-12-05
Filing date: 1995-11-30
Publication date: 1999-04-29
Also published as: EP0796316A1; MX9704132A; WO1996017919A1; AU4412896A

Description

<div class="application article clearfix" id="description"> New Zealand Paient Spedficaiion for Paient Number £98600 New Zealand No 298600 International No PCT/US95/15591 TO BE ENTERED AFTER ACCEPTANCE AND PUBLICATION Priority dates 05 12 1994,18 09 1995, Complete Specification Filed 30 11 1995 Classification (6) C11D3/37 Publication date 29 April 1999 Journal No 1439 NO DRAWINGS NEW ZEALAND PATENTS ACT 1953 COMPLETE SPECIFICATION Title of Invention Granular detergent compositions containing deflocculating polymers Name, address and nationality of apphcant(s) as in international application form COLGATE-PALMOLIVE COMPANY, 300 Park Avenue, New York 10022, United States of America _ WO 96/17919 ♦ 29CGOO 1 PCIYDS95/1S591 ORANULAR DETERGENT COMPOSITIONS (Y>NTAlNlNfinEFI-Onan.AnNGPOI.YMFRS BACKfiROTTND OF THE INVENTION 5 10 35 L Field of the Invention This invention relates to granular detergent compositions containing an end-capped hydrophilic polymer as a crutcher slurry 15 deflocculating agent. 2. Description of the Related Art Heavy duty granular detergents useful for hand and machine 20 washing of laundry are well known materials which have been described in a number of patents and in the literature They are generally prepared by spray drying an aqueous based crutcher slurry containing at least one or a compatible mixture of two or more detergent active surfactants selected from anionic, cationic, 2 5 nonionic, zwitte-i^nic and amphoteric species. Such compositions may also contain detergency builder components and/or sequestering agents such as inorganic phosphates or phosphonates, alkali metal carbonates, alkali metal aminopolycarboxylates such as salts of nitrilotriacetic acid and salts of ethylenediamine-tetraacetic 3 0 acid, alkali metal silicates, alummosilicates, various zeolites and mixtures of two or more of these Other components which may be present in such detergents include optical brighteners, enzymes and their stabilizers, perfumes, colorants, antifoammg agents, e.g. silicone compounds, preservatives and like known additives. One of the common methods for preparing powder detergents is to first form a pumpable aqueous slurry or dispersion of the detergent components, generally referred to as a crutcher slurry, and then WO 96/17919 PCT/US95/15591 atomizing the slurry by pumping it through an atomizing nozzle a». a pressure of about 400 to 2000 psi into a spray-drying tower along with air introduced at a temperature of 300-1000°F The air contacts the slurry to provide a hot drying gas for the droplets of 5 the slurry, thereby evaporating most of the water The resulting particles or beads are collected at the bottom of the tower while the moisture and heated air exits at the top There is a trend in the detergent industry to provide powder 10 detergent compositions having higher concentrations of active ingredients (payload), including surfactants These include super concentrated, heavy duty detergent powder formulations containing greater than about 25% by weight of surfactant While it may appear simple enough to provide such materials, there is a 15 limiting factor in terms of the maximum quantity of surfactant which can be included in the crutcher slurry while still maintaining a slurry with sufficiently low viscosity such that it can be pumped to the spray dry tower, e.g viscosity of about 500,000 or less 20 The crutcher slurry generally may be characterized as composed of lamellar droplets dispersed in an aqueous electrolyte/builder phase The lamellar droplets consist of an onion-like configuration of concentric bi-layers of surfactant molecules between which layers are trapped water or electrolyte solution. Such slurries may 25 also contain suspended solids such as the suspended or dissolved builders referred to above To facilitate spray drying, it is also preferred to have as high a level of non-aqueous solids in the crutcher slurry as possible, but without increasing the viscosity of the slurry to a poinf where it is non-pumpable. Also, as the level of 3 0 surfactant m the crutcher slurry is increased, the volume fraction of lamellar droplets suspended is also increased, resulting in a diminished spacing between droplets Contact of the suspended lamellar droplets with one another can lead to a congealing or flocculation phenomenon, resulting in a marked increase in the 3 5 viscosity of the slurry due to formation of a network throughout the slurry. Slurries containing flocculated lamellar droplets and high solids levels may be unacceptable because of an inability to pump the viscous slurry from the mixing tank through the drying WO 96/17919 3 PCT/DS95/15591 and granulation process. In addition, higher levels of surfactant induces the slurry to foam up under mixing conditions, requiring the addition of foam control agents such as silicones. 5 Concentrated liquid detergents containing a polymeric additive are disclosed in the prior art The polymer serves to stabilize the detergent and control viscosity One approach to enhance the stability of such liquid detergent 1 0 compositions is the inclusion of minor amounts, e.g., 0.01 to 5% by weight, of a deflocculating polymer into the detergent formulation For example, U.S Patent 5,147,576 discloses random interpolymers derived from hydrophilic monomers, such as acrylic acid, and also containing one or more copolymerized monomers having pendant 15 hydrophobic side chains randomly dispersed along the polymer chain. Use of these interpolymers in detergent compositions is disclosed to hinder or prevent flocculation of lamellar surfactant droplets dispersed in the detergent, and thus enhance stability. Granular detergent compositions containing similar deflocculating 20 polymers are disclosed in WO/91/Q9932. Hydrophilic polymeric materials have also been used in liquid detergent compositions as viscosity control agents. For example, U.S. Patent 4,715,969 and its counterpart UK 2,168,717 disclose that 25 the addition of less than about 0.5% by weight of a polyacrylate polymer, e.g. sodium polyacrylate, having a molecular weight from about 1,000 to 5,000, to aqueous detergent compositions containing primarily anionic surfactants will stabilize the viscosity of the composition and prevent a major increase in viscosity after a period 3 0 of storage of the formulated composition Also, EPO 301,883 discloses similar compositions containing from about 0.1 to 20% by weight of a viscosity reducing, water soluble polymer such as polyethylene glycol, dextran or a dextran sulfonate 3 5 Polymeric additives have also been used in powder detergents. For example, Canadian Patent 1,174,934 discloses granular detergents containing surfactant, crystalline aluminosilicate and alkaline salt builders, and from about 0.1 to 10% by weight of a film forming, WO 96/17919 4 PCT/US95/15591 water soluble acidic polymer such as acrylic or sulfate functional polymers. The polymers are said to provide dried granules having superior free-flowing characteristics and good solubility in water. Also, U.S. Patent 3,308,067 discloses a granular detergents 5 containing a water soluble salt of a homopolymer of an aliphatic polycarboxylic acid as a polyelectrolytic builder material. U.S. Patent Nos 3,668,230, 3,839,405; 3,772,382, and 3,776,874 issued to Uniroyal, Inc. disclose alieyl sulfide, alkyl sulfoxide and 10 alkyl sulfone terminated oligomers for use in emulsion polymerization. The oligomers are broadly stated to be useful as surface active agents, emulsifiers and thickeners. EP 623670A describes the use of stabilizers in an aqueous 15 surfactant composition to reduce the flocculation of systems containing a flocculable surfactant. The stabilizers are described as surfactants having a hydrophobic portion and a hydrophilic portion The hydrophilic portion is typically a polymer linked at one end to the hydrophobic portion. 20 SUMMARY OF THE INVENTION The present invention provides for concentrated granular detergent compositions comprising a mixture of: 25 a) from about 15 to about 50% by weight of a surfactant; b) at least one detergent builder, and 30 c) from about 0.01 to about 7.5% by weight of a deflocculating polymer composition containing polymer chains of the structure P-QR, wherein P represents a polymer chain segment of a hydrophilic polymer, and QR represents a hydrophobic end-cap group wherein R is an organic 35 hydrophobic radical containing from about 4 to 28 carbon atoms, and Q is selected from the group consisting of O, CO2, S, SO, S02, NR\ P04R', PO3R1, Si OR'R", Si R'R", CR'OH, CR'R" and WO 96/17919 PCT/US95/15591 5 CR'OR" wherein R' and R" are each hydrogen, an alkyl group containing from 1 to 4 carbon atoms or an aryl group, and d) water 5 The granular detergent is prepared by drying a crutcher slurry comprising an aqueous dispersion of the organic surfactant, detergent builder, deflocculating polymer and other ingredients which may be present in the composition The presence of the 10 deflocculating polymer in the slurry retards the propensity of the lamellar droplets dispersed in the aqueous electrolytic phase of the slurry to flocculate, particularly where the droplets occupy a higher volume ratio as the result of high concentrations of surfactant present in the detergent The resulting slurry has a much lower 15 viscosity than a similar slurry which does not contain the deflocculating polymer, and is thus more flowable and more easily pumped to and through the drying stage of the manufacturing process. 20 DETAILED DESCRIPTION OF THE INVENTION The granular compositions of the invention contain one or a compatible mixture of two or more detergent active surfactants which may be selected from anionic, cationic nonionic, zwitterionic 25 and amphoteric species. Suitable anionic detergents include the water-soluble alkali metal salts having alkyl radicals containing from about 8 to about 22 carbon atoms, the term alkyl being used to include the alkyl portion 30 of higher acyl radicals. Examples of suitable synthetic anionic detergent compounds are sodium and potassium alkyl sulphates, especially those obtained by sulphatmg higher (C8-C18) alcohols produced, for example, from tallow or coconut oil, sodium and potassium alkyl (C9-C2O) benzene sulfonates, particularly sodium 3 5 linear secondary alkyl (C10-C15) benzene sulfonates; sodium alkyl glycerol ether sulfates, especially those ethers of the higher alcohols derived from tallow or coconut oil and synthetic alcohols derived from petroleum; sodium coconut oil fatty monoglyceride sulfates WO 96/17919 PCT/US95/15591 6 and sulfonates; sodium and potassium salts of sulfuric 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 lsethionic acid and neutralized 5 with sodium hydroxide; sodium and potassium salts of fatty acid amides of methyl taurine, alkane monosulfonates such as those derived from reacting alpha-olefins (C8-C2O) with sodium bisulfite and those derived from reacting paraffins with SO2 and Cl2 and then hydrolyzing with a base to produce a random sulfonate, and 10 olefin sulfonates which term is used to describe the material made by reacting olefins, particularly C10-C20 alpha-olefins, with SO3 and then neutralizing and hydrolyzing the reaction product The preferred anionic detergents are sodium (C10-CI6) linear alkyl benzene sulfonates, (C10-C18) alkyl polyethoxy sulfates and 15 mixtures thereof. The more preferred anionic detergent is one or a mixture of linear or branched (preferably linear) higher alkylbenzene sulfonate and alkyl polyethoxy sulfates While other water soluble linear higher 20 alkylbenzene sulfonates may also be present in the formulas of the present invention, such as potassium salts and in some instances the ammonium and/or alkanolammonium salts, where appropriate, it has been found that the sodium salt is highly preferred, which is also the case with respect to the alkyl polyethoxy sulfate detergent 2 5 component The alkylbenzene sulfonate is one wherein the higher alkyl group is of 10 to 16 carbon atoms, preferably 12 to 15, more preferably 12 to 13 carbon atoms The alkyl polyethoxy sulfate, which also may be referred to as a sulfated polyethoxylated higher linear alcohol or the sulfated condensation product of a higher fatty 3 0 alcohol and ethylene oxide or polyethylene glycol, is one wherein the alkyl group is of 10 to 18 carbon atoms, preferably 12 to 15 carbon atoms, and which includes 2 to 11 ethylene oxide groups, preferably 2 to 7, more preferably 3 to 5 and most preferably about 3 ethylene oxide groups 35 The anionic detergent may be present in the granular detergent at a level of from about 15 to about 50% by weight, more preferably from about 20 to about 45% by weight Where mixtures of two or WO 96/17919 7 PCT/US95/15591 more different anionic detergents are used, such as the sulfate and sulfonate mixtures described above, ihey may be mixed in the relative proportions in the range of about 5 to 95% by weight of each type. 5 The composition of this invention may also contain supplementary nonionic and amphoteric surfactants Suitable nonionic surfactants include, m particular, the reaction products of compounds having a hydrophobic group and a reactive hydrogen atom, for example 10 aliphatic alcohols, acids, amides and 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 15 the reaction products of propylene oxide and ethylenediamine. Other so-called nonionic detergent compounds include long chain tertiary amine oxides, long-chain tertiary phosphine oxides, dialkyl sulfoxides, fatty (C8-C18) esters of glycerol, sorbitan and the like, alkyl polyglycosides, ethoxylated glycerol esters, ethoxylated 20 sorbitans and ethoxylated phosphate esters. The preferred non-ionic detergent compounds are those of the ethoxylated and mixed ethoxylated-propyloxylated (C6-C18) fatty alcohol type The nonionic surfactants may be present in the 25 composition at a preferred level of from about 1 to 15% by weight It is also possible 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, alk(en)yl 30 succinate, for example dodecenyl succinate, and fatty acids derived from castor oil, rapeseed oil, groundnut oil, coconut oil, palmkernel oil or mixtures thereof The sodium or potassium soaps of these acids can be used When used, the level of soap in compositions of the invention is from about 0 5 to 15% by weight of the 35 composition. Particularly preferred combinations of surfactants include: WO 96/17919 8 PCT/US95/15591 1. A mixture which comprises about 15 to 30% by wt linear alkylbenzene sulfonate wherein the alkyl group contains from about 10 to 16 carbon atoms and about 1 to 10% by wt. of alkyl polyethoxy sulfate wherein the 5 alkyl is of 10 to 18 carbon atoms and the polyethoxy is of 2 to 7 ethylene oxide groups. 2. A mixture which comprises one or both of the anionic surfactants listed in 1 above and a nonionic ethoxylated 10 fatty alcohol wherein the fatty alcohol is of 8 to 18 carbon atoms and the polyethoxy is of 2 to 7 oxide groups. The anionic to nonionic surfactant ratio is from about 14 to 10:1 15 A more detailed illustration of the various detergents and classes of detergents mentioned may be found in the text Surface Active Agents. Vol. II, by Schwartz, Perry and Berch (Interscience Publishers, 1958), m a series of annual publications entitled McCutcheon's Determents and Emulsifiers. issued in 1969, or in 20 Tensid-Taschenbuch. H Stache, 2nd Edn. Carl Hanser Verlag, Munich and Vienna, 1981. The composition of this invention also includes at least one detergency builder. Suitable builders include phosphorous-25 containing inorganic salts, organic builders and non-phosphorous-containing builders. The prime function of the builder is to complex with hard water cations which form salts insoluble in water, for example calcium and magnesium cations, through the mechanism of sequestration or cation exchange. 30 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 3 5 include sodium and potassium tripolyphosphates, phosphates and hexametaphosphates Phosphonate sequestrant builders may also be used Examples of organic detergency builders which may be used include the alkali metal, ammonium and substituted WO 96/17919 9 PCT/US95/15591 ammonium polyacetates, carboxylates, polycarboxylates, polyacetyl carboxylatcs and polyhydroxysulphonates Specific examples include sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid, nitrilotriacetic 5 acid, oxydisuccinic acid, melitic acid, benzene polycarboxylic acids, tartrate mono succinate, tartrate di succinate, alk(en)yl succinates and citric acid. Other organic detergency builders include water-soluble alkali metal carbonates and bicarbonates, as well as mixtures thereof with phosphates, e.g , a mixture of sodium 10 carbonate and sodium tnpolyphosphate Builders other than phosphorous-containing compounds may also be used Preferred builders for use in phosphorous-free compositions include cation-exchanged amorphous or crystalline 15 aluminosilicates of natural or synthetic origin Suitable aluminosilicate zeolites include "zeolite A", "zeolite B", "zeolite X", "zeolite Y" and "zeolite HS" The more preferred zeolite is crystalline sodium silicoaluminate zeolite A Preferably, the zeolite should be in a finely divided state with the ultimate particle 20 diameters being up to 20 microns, e.g., 0.005 to 20 microns, preferably from 0.01 to 15 microns and more preferably of 0.01 to 8 microns mean particle size, eg 3 to 7 microns, if crystalline, and 0.01 to 0 1 microns if amorphous Although the ultimate particle sizes are much lower, usually the zeolite particles will be of sizes 25 within the range of 100 to 400 mesh, preferably 140 to 325 mesh Zeolites of smaller sizes will often become objectionably dusty and those of larger sizes may not be sufficiently and satisfactorily suspended in the crutcher slurry 30 In another embodiment of the invention where phosphorous-free builders are used, the builder may comprise water soluble non-phosphorous containing compounds which dissolve in the aqueous phase of the crutcher slurry forming an electrolyte solution Examples of such builders include the alkali metal carboxylates 3 5 referred to above, e.g , sodium citrate, used alone or in a mixture with water soluble alkali metal carbonates or bicarbonates, e.g., sodium or potassium carbonate WO 96/17919 10 PCT/US95/15591 10 Mixtures containing two or more of the above described detergency builders may also be employed The builder or mixture of builders may be present in the granular detergent in the range of from about 15 to about 60% by weight of the composition, more preferably from about 20 to about 50% by weight Where the builder is a zeolite material, it is normally present in the range of from about 5 to 30% by weight of the composition, and is preferably used in combination with other compatible builder materials The granular detergent also preferably contains one or a mixture of alkali metal silicates which function to form a tough, glassy film capable of strengthening granule walls and imparting better flow characteristics to the dried detergent granules Preferred silicates 15 are those having an S1O2 to alkali metal oxide ratio of 1 5 to 2.0 since these tend to be more water soluble Sodium silicate is the preferred silicate The silicate may be present in the detergent granules at a level of from about 3 to about 40% by weight, more preferably from about 5 to about 35% by weight The key 20 ingredient in the compositions of the present invention is the hydrophobically modified deflocculating polymer which both stabilizes the crutcher slurry and decreases its viscosity The hydrophobic end groups present in the otherwise hydrophilic polymer become enveloped in the lamellar droplets formed by the 25 surfactant phase of the slurry, thereby both stencally and electrostatically inhibiting flocculation of these droplets, even at relatively high concentrations This results in a stable, lower viscosity, pumpable slurry 30 Deflocculating polymers useful in accordance with this invention are characterized as comprising a hydrophilic polymer chain segment (P) having a hydrophobic moiety (QR) covalently attached to a terminal carbon atom present in at least some of the hydrophilic chain segments These polymers may be generally 3 5 characterized as containing the structure P-QR wherein P represents the hydrophilic polymer and R is an organic hydrophobic radical coniainmg from about 4 to 28 carbon atoms, WO 96/17919 11 PCT/US95/15591 more preferably an alkyl radical containing from about 6 to 18 carbon atoms. Q represents a group or molecule which is capable of linking the 5 hydrophilic polymer P with the organic hydrophobic radical R and thereby acts as a polymer chain terminator (or initiator) In general, Q may be selected from the group consisting of O, C02, S, SO, SO2, NR\ P04R\ P03R\ Si OR'R\ Si R'R", CR'OH, CR'R", and CR'OR" wherein R' and R" are each hydrogen, an alkyl group containing 1 to 10 4 carbon atoms or an aryl group. R is a C4-C28 alkyl, alkenyl or aralkyl group, preferably an alkyl or aralkyl group containing 6 to 18 carbon atoms The preferred polymers of the invention are terminated with an alkyl sulfide, alkyl-sulfoxide or alkyl-sulfone end-cap group. 15 Monomers which may be polymerized to form the hydrophilic polymer segment include one or a mixture of water soluble monomers or a combination of water soluble and relatively water insoluble monomers such that the resulting polymers are water 20 soluble at ambient temperatures to the extent of greater than about 10 grams per liter Examples of suitable such monomers include ethylenically unsaturated amides such as aciylamide, methacrylamide and fumaramide and their N-substituted derivatives such as 2-acrylamido-2-methylpropane sulfonic acid, 25 N-(dimethylaminomethyl) acrylamide as well as N-(trimethylammoniummethyl) acrylamide chloride and N-(trimethylammoniumpropyl) methacrylamide chloride, ethylenically unsaturated carboxyhc acids or dicarboxylic acids such as acrylic acid, maleic acid, methacrylic acid, itaconic acid, 30 fumaric acid, crotonic acid, aconitic acid and citraconic acid; and other ethylenically unsaturated quaternary ammonium compounds such as vinyl-benzyl trimethyl ammonium chloride, sulfoalkyl esters of unsaturated carboxylic acids such as 2-sulfoethyl methacrylate, aminoalkyl esters of unsaturated caiboxylic acids 35 such as 2-ammoethyl methacrylate, dimethyl ammoethyl (meth)acrylate, diethyl aminoethyl (meth)acrylate, dimethyl aminomethyl (meth)acrylate, diethyl aminomethyl (meth)acrylate, and their quaternary ammonium salts; vinyl or allyl amines such as WO 96/17919 12 PCT/US95/15591 vinyl pyridine and vinyl morpholine or allylamine; diallyl amines and diallyl ammonium compounds such as diallyl dimethyl ammonium chloride, vinyl heterocyclic amides such as vinyl pyrrohdone; vinyl aryl sulfonates such as vmylbenzyl sulfonate; 5 vinyl alcohol obtained by the hydrolysis of vinyl acetate; acrolein; allyl alcohol; vinyl acetic acid, sodium vinyl sulphonate, sodium allyl sulphonate, as well as the salts of the foregomg monomers. These monomers may be used singly or as mixtures thereof. 10 Optionally, the hydrophilic polymer segment may contain small amounts of relatively hydrophobic units, e.g , those derived from polymers having a solubility of less than 1 g/1 m water, provided that the overall solubility of the hydrophilic polymer still satisfies the solubility requirements as specified above Examples of 15 relatively water insoluble polymers are polyvinyl acetate, polymethyl methacrylate, polyethyl acrylate, polyethylene, polypropylene, polystyrene, polybutylene oxide, polypropylene oxide and polyhydroxypropyl acrylate. 20 A particular class of preferred alkyl sulfide terminated polymers in accordance with the invention may be represented by the following structural formula: 25 30 where R is a straight or branched chain primary, secondary, or tertiary alkyl group having 5 to 20 carbon atoms, Ri and R3 are each hydrogen, methyl, ethyl, or —COOH, R2 and R4 are each hydrogen, methyl, ethyl, —COOH, or —CH2COOH, Y is selected from the group consisting of —COOH, —CONH2, —OCH3, —OC2H5, and —CH2OH; X is selected from the group consisting of —COOC2H4OH, —COOQ3H6OH, —CONHCH2OH, —CONHCH3, —CONHC2H5, —CONHC3H7, WO 96/17919 13 PCT/US95/15591 —COOCH3, —COOC2H5, —CN, —OOCCH3, —OOCC2H5, and —OXX3fcCHOCH2. The degree of polymerization, a+b, is generally between 2 and 50, 5 and the mole fraction of the monomer having the X functional group, a/(a+b), may vary from 0 to 0 6, and is preferably less than 0.5 and most preferably is 0.2 to 0.5 The presence of a monomer having the X functional group is optional hence the value of "a" will be zero for polymers containing only monomers having a Y 10 functional group. A comprehensive description of these alkyl sulfide terminated polymers and their method of preparation is disclosed in U.S. Patent 3,839,405, the complete disclosure of which is incorporated herein by reference. 15 Particularly preferred polymers for use herein comprise a hydrophilic polymer terminated by a hydrophobic mercapto end-cap group derived from a mercaptan having the structure RSH, where R is an alkyl or aralkyl radical having 4 to 28 carbon atoms R should be of sufficient chain length such that it exhibits oleophilic 20 properties, i.e., it is miscible with the oily lamellar droplet or micelle phase of the detergent composition. Preferably, the mercaptans are alkyl or aralkyl mercaptans containing about 6 to 18 carbon atoms such as hexyl mercaptan, decyl mercaptan, dodecylbenzyl mercaptan, dodecyl mercaptan and octadecyl 25 mercaptan. The hydrophilic polymer backbone may also be advantageously chain terminated with a sulfoxide or a sulfone group. A class of preferred polymers for use herein may be represented by the 3 0 following structural formula* O R S < R1 \ ^ R3 R4 X H ■H Y 'b WO 96/17919 14 PCT/US95/15591 wherein R, Rl, R2. R3. R4> X, Y, the degree of polymerization a+b, and the mole fraction a/(a+b) are as defined above; Z is either oxygen or not present . When Z is oxygen the end-cap group is an alkyl sulfone; when Z is not present the end-cap group is an alkyl 5 sulfoxide. A comprehensive description of these type alkyl-sulfoxide and alkyl-sulfone terminated polymers and their method of preparation is disclosed in U.S Patent Nos.- 3,772,382; 3,776,874, and 3,668,230, the complete disclosures of which are incorporated herein by reference. 10 By example, mercapto terminated polymers may be prepared by free radical polymerization of the hydrophilic monomer or monomer mixture in an aqueous or water/alcohol medium in the presence of a water soluble free radical initiator and in the 15 presence of an RSH mercaptan. The molar ratio of monomer to mercaptan may generally range from about 10.1 to about respectively, more preferably from about 25:1 to about 100:1 respectively. Under free radical polymerization conditions, a number of RS free radicals will be generated which may serve to 20 initiate polymerization of additional monomer or these radicals can couple with a growing polymer chain, resulting in a mixed polymer product wherein at least some of the chains have the structure P-QR as described above. The number of P and P-QR chains present in the mixed polymer product will vary depending on 25 polymerization conditions, average molecular weight of the polymer and the quantity of mercaptan present in the polymerization mixture Preferably from about 25 up to about 95% of the polymer chains are end-capped by the SR mercapto hydrophobe. 30 Polymerization may be conducted by the general procedures described in U.S. Patent 5,021,525, the complete disclosure of which is incorporated herein by reference The preferred aqueous polymerization medium comprises a mixture of at least 50% by weight of water and miscible cosolvent such as a Cl to C4 alcohol, 3 5 e.g., isopropanol, which tends to retard precipitation of the developing end-capped polymer from solution Polymerization initiators which may be used include water soluble initiators such as hydrogen peroxide, persulfates, perborates and permanganates, WO 96/17919 Q 0 - , P^T/U895/15$91 15 t~ present in solution at levels generally in the range of from about 0.1 to 5% by weight Polymerization may be conducted by initially charging an initiator, 5 e.g sodium persulfate, into an aqueous polymerization medium, followed by gradual introduction of a mixture comprising monomer and mercaptan into the medium at a level of from about 10 to 55% by weight of total reactants, and heating the mixture at a temperature in the range of from about 70 to 99° C for a period of 10 time sufficient to form polymer of the desired molecular weight, generally from about 3 to 6 hours Preferably, only a portion of the monomer and initiator is added to the medium initially, followed by the addition of remaining monomer and initiator later during the polymerization The polymer may then be recovered by stripping 15 the cosolvent, e.g., isopropanol and at least part of the water, followed by neutralization of the polymer with caustic, e.g., sodium hydroxide Preferred deflocculating polymers useful for the purposes of this 2 0 invention have a weight average molecular weight, as measured by gel permeation chromatography using polyacrylate standards, in the range of from about 200 to 50,000, more preferably from about 200 to 25,000 and most preferably for polymers based on polyacrylic and polymethacrylic acid, from about 3,000 to 10,000 2 5 The most preferred polymers are hydrophilic homopolymers such as polyacrylic or polymethacrylic acid and copolymers of acrylic or methacrylic acid with less than 50 wt% of maleic acid (anhydride), wherein the bulk of the polymer chains are end-capped with a single hydrophobic segment derived from dodecyl mercaptan. 30 The deflocculating polymer is generally added to the formulation at levels such that the content of the polymer in the final spray dried granular product ranges from about 0.01 to about 7.5% by weight, more preferably from about 0 5 to about 5% by weight, and most 3 5 preferably from about 1 to about 3% by weight These polymers and their method of preparation are further disclosed in US Patent 5599784, Cr lj Z " " ' f' "u" -3 MAR 1999 P r r i ~ 1 \ I f I V. J I J _ _ - - - - - - • < - t ' _ ,, t I IR 5412 16 298600 The aqueous phase of the crutcher slurry is electrolytic and thus contains a water soluble salt Where the builder present in the detergent is itself a water soluble salt, e g „ where the builder i< an alkali metal carbonate phosphate or citrate, no additional electrolyte need be added Where the builder is water insoluble, e g , a zeolite, then alkali metal hahdes or sulfates may be included as necessary to form the aqueous electrolyte solution 10 The granular detergent composition is prepared by drying a crutcher slurry comprising an aqueous dispersion of the afc^ve components The slurry generally contains from about 25 to <5% by weight water more preferably 35 to 50% by weight water, same of which is present as a diluent in some formulation components, 15 eg., surfactants, and some of which is added when the slurry is prepared After drying, the detergent granules generally couEam 15% by weight water or less, generally from 2 to 15%, by we^ht, water and preferably from 1 to 10% by weight 20 Various, adjuvants, both aesthetic and functional, may be present m the detergent compositions of the present invention, such as fluorescent bnghteners, perfumes and colorants The fluorestent brighteners include the well known stilbene derivatives, mclufcng 2 5 the cotton and nylon brighteners, such as those sold under the trademark TinopalO, e g. 5BM The perfumes that are empl^ed usually include essential oils, esters, aldehydes and/or alcohols, all of which are known in the perfumery art. The colorants aay include dyes and water dispersible pigments of various tyjes, 3 0 including ultramarine blue. Titanium dioxide may be utilized to lighten the color of the product further or to whiten it Inorgsoic filler salts, such as sodium sulfate and sodium chloride may be present, as may be antiredeposition agents, such as sofam carboxymethylcellulose, enzymes, such as proteases, amylases and 3 5 lipases, bleaches, such as sodium perborate or percarbonate or chlorine-containing materials, bactericides, fungicides; anti-foam agents, such as silicones, antisoiling agents, such as copolyesters; AMENDE'J ontc! ®W0 96/17919 PCT/US95/15591 17 preservatives, such as formalin; foam stabilizers, such as lauric myristic diethanolamide, and auxiliary solvents, such as ethanol. Normally the individual proportions of such adjuvants will be less than 3%, often less than 1% and sometimes even less than 0.5%, 5 except for any fillers and solvents, and additional detergents and builders, for which the proportions may sometimes be as high as 10%. The total proportion of adjuvants, including non-designated synthetic detergents and builders, will normally be no more than 20% of the product and desirably will be less than 10% thereof, 10 more desirably less than 5% thereof Of course, the adjuvants employed will be non-interfering with the washing and the softening actions of the detergent and will not promote instability of the product on standing Also, they will not cause the production of objectionable deposits on the laundry 15 These adjuvants are most preferably mixed with the finished granular detergent after the drying operation. The viscosity of the crutcher slurry composition immediately after 20 completion of the slurry mixing procedure will vary depending on the solids content of the slurry and the amount of deflocculating polymer present in the slurry For slurries containing relatively low solids level, e.g. 35 to 50% by weight solids, the viscosity will range from about 2,000 to 100,000 cps For slurries containing 25 higher solids levels, e.g 50-65% by weight, the viscosity will range from about 100,000 to 500,000 cps, as measured using a Brookfield Viscosimeter Model LVT-II at an angular velocity of 12 rpm and at 25°C. Spindle No 3 is used to measure viscosities below 10,000 cps and spindle No 4 is used for viscosities above 10,000 cps. The 30 more preferred viscosity will be in the range of from about 100,000 to 500,000 cps, most preferably in the range of about 200,000 to 400,000 cps The pH of the slurry will generally be in the range of from about 7 to about 12, preferably 10 to 12, and pH may be adjusted if necessary by adding to the slurry appropriate amounts 3 5 of a basic solution such as 50% KOH The components of the crutcher slurry may be mixed in any suitable order which will lead to the development of a uniform WO 96/17919 PCT/US9S/15591 18 dispersion. In a preferred procedure, water and all of the liquids (silicate, surfactant, and polymer) are mixed first with high shear mixing in the crutcher If the formula contains phosphate builder, it is added next, there is a delay step while the phosphate hydrates 5 Subsequent solids then added include soda ash, zeolite (if no phosphate), sodium sulfate, brightener, and salt The silicone defoamer is added last to dearate the slurry just prior to it being dropped out of the crutcher to a drop tank where it will be pumped to the spray tower. The crutcher slurry will generally have a final 10 solids content of about 40-75% by weight, more preferably from about 50 to 70% by weight The slurry may then be dried using any of the well known drying processes such as spray drying, fluid bed drying, flash drying, 15 microwave drying and the like The preferred process is the spray dry process. In a typical spray dry process, the crutcher slurry is atomized by pumping it into an atomizing nozzle of a spray dry tower at a pressure which may range from about 400 to 2,000 psi Typical dimensions of a spray dry tower range from 35-100 feet in 20 height and 12-30 feet in diameter. At the base of the tower, air is introduced at a temperature of from about 300°-1000°F. which contacts the atomized slurry to provide a hot drying gas for the droplets of the slurry, thereby evaporating most of the water. The resulting dried granules are collected at the tower base and cooled 25 Heat or water-sensitive ingredients such as perfumes may be post added to the tower granules m a subsequent mixing or blending operation The following examples are illustrative of the invention. The following ingredients in parts by weight (grams) were mixed in the order shown in laboratory beaker using a high speed propeller 3 5 mixer to form a pumpable crutcher slurry* 30 EXAMPLE 1 Water Anionic Surfactant (LDBS)* 11.5 60 0 WO 96/17919 19 PCT/US95/15591 Deflocculating Polymer** Potassium Tripolyphosphate Sodium Silicate Solution 5.4 39.0 17.0 5 * Linear alkylbenzene sulfonate detergent containing 10-14 carbon atoms. ** Copolymer of acrylic and maleic acids endcapped with dodecyl mercaptan and having a weight average molecular weight of about 10,000 and about a 50:1 mole ratio of hydrophile to dodecyl 10 hydrophobe. Mixing time was approximately 30 minutes The resulting slurry had a viscosity of 8,000 + 1,000 cps measured using a Brookfield #3 spindle at 12 RPM, and was readily flowable and pumpable as 15 required for subsequent spray drying to produce a granular detergent. 20 Example 1 was repeated as set forth above except that the deflocculating polymer was omitted from the formulation and replaced with an equal amount of sodium polyacrylate polymer having a molecular weight of about 4500. The resulting formulation was found to have a viscosity in excess of 50,000 cps, 2 5 could not be poured from the beaker and thus could not be pumped to or through a spray dry tower 3 0 The ingredients listed below (in grams) were mixed as in Example 1 for a period of about 15 minutes to form crutcher slurries having a non-aqueous solids content of about 56% CONTROL EXAMPLE 2 Example 3 EXJL CONTROL 35 Water LDBS Sodium Silicate 119 408 112 119 408 112 WO 96/17919 20 PCT/US95/15591 Deflocculating Polymer* 2 Control Polymer** -- 2 Sodium Hydroxide 50 50 Potassium Tnpolyphosphate 256 25 6 5 Sodium Sulfate 14 14 Viscosity 235,000 900,000 * Copolymer of acrylic and maleic acids endcapped with dodecyl mercaptan and having a weight average molecular 10 weight of about 4000 and about a 25:1 mole ratio of hydrophile to dodecyl hydrophobe ** Acrylic homopolymer having a weight average molecular weight of about 4500 15 The viscosity of the resultant slurry of Example 3 was measured as 235,000 cps using a Brookfield DV-11 viscometer equipped with a helipath stand; the control slurry had a viscosity of 900,000 cps and was too thick to be pumpable in a spray dry process 20 Examples 4-6 Example 3 was repeated except that the water content of the slurry formulation was lowered to provide solids contents of 61, 63 and 25 65% by weight respectively. Viscosity data for each slurry was obtained as in Example 3 with the following results: % SOLIDS VISCOSITY (cps) 30 Ex. 4 6 1 220,000 Ex.5 6 3 518,000 Ex 6 6 5 1,500,000 The above data demonstrate that formulations containing 2% by 3 5 weight of defocculating polymer and a solids level up to and greater than about 63% by weight exhibit viscosities lower than the control formulation at a solids level of only 59% by weight. WO 96/17919 PCT/US95/15591 21 Example 7 Slurries were prepared as set forth in Example 3 using the same deflocculating polymer and control polymer as described in 5 Example 3. The slurries were then spray dried under the conditions described below. The crutcher slurry and post-spray dried finished product compositions are as set forth in Table 1 WO 96/17919 22 PCT/US95/15591 TABLE 1 Example 7 Control Example Ingredient Crutchsr% Finished Crutcher% Finished Product Product% Water 0.2 8 13.9 8 Sodium Sulfate 55 7.6 4.8 7.6 LDBS 46.16 28 40.1 28 Brightener 0.096 0 12 0 08 0.012 Silicate 12.7 7.5 11 0 7.5 TPP 29 36 25.2 36 NaCl 1.6 2 1.4 2 Deflocc. Polymer 46 2 — -- Control Polymer — — 35 2 Silicone 0.02 0.03 0.02 0.03 Spray Conditions were as follows: Deflocculating Polymer Control Air flow (CFM) 3200 3200 Spray Pressure (PSI) 1100-1250 1250 cfm = cubic feet per minute psi = pounds per square inch PROPERTIES EZJL CONTROL Density of Finished Product 0.32 0.52 Powder % Solids in Crutcher Slurry 66.5% 58% Slurry Viscosity (cps) 239,900 361,000 </div>

Claims

<div class="application article clearfix printTableText" id="claims"> WO 9d/17919 23 PCT/US95/15591 The formulation of Example 7 has a considerably lower viscosity than the control even though the slurry solids level is over 8% higher than the Control. Also, the density of the spray dried 5 product of Example 7 was considerably lower than that of the Control. 24 CLAIMS 298 6 0 C What is claimed is 5 I A concentrated spray-dried granular detergent composition comprising mixture of ^ a) from about 15 to 50% by weight of surfactant, 1 0 b) at least one detergent builder, and c) from about 0 01 to about 7 5% by weight of a deflocculating polvmer composition having a weight average molecular weight in the range of from about 1,500 to about 1 5 50,000 and containing polymer chains of the structure P-SK. wherein P represent"; a polymer chain segment of a hydrophilic polymer and SR represents a mercapto end-cap group, R being an organic hydrophobic ladical containing from about 4 to 28 carbon atoms 20 2 The composition of claim 1 wherein said surfactant comprises at least one anionic detergent selected from an anionic sulfate or sulfonate 2 5 3 The composition of claim 2 containing from about 15 t« 30% by weight of an alkyl benzene sulfonate anionic detergent having f^om about 10 to 16 alkyl carbon atoms 4 The composition of claim 2 containing from about 1 tg 3 0 about 10% by weight of a sodium or potassium alkyl pol>ethoxj sulfate anionic detergent wherein the alkyl group contains frost about 10 to 18 carbon atoms and the polyethoxy is of 2 to ? ethylene oxide groups 3 5 5 The composition of claim 3 wherein said ionic deterge® comprises a mixture of said alkyl benzene sulfonate and from abousj 1 to about 10% by weight of a sodium or potassium alkyf! polyethoxy sulfate wherein the alky! group contains from about 1® A n. I>£_E> shCXT WO 96/17919 25 PCT/US95/15591 5. The composition of claim 3 wherein said ionic detergent comprises a mixture of said alkyl benzene sulfonate and from about 1 to about 10% by weight of a sodium or potassium alkyl polyethoxy sulfate wherein the alkyl group contains from about 10 5 to 18 carbon atoms and the polyethoxy is of 2 to 7 ethylene oxide groups. 6. The composition of claim 3 or 5 further containing from about 1 to 15% by weight of a nonionic ethoxylated fatty alcohol 10 wherein the fatty alcohol contains about 6 to 18 carbon atoms. 7. The composition of claim 1 wherein said hydrophilic polymer chain segment P is polyacrylic or polymethacrylic acid. 15 8. The composition of claim 1 wherein said hydrophilic polymer chain segment P is a copolymer containing at least 50% by weight of polymerized acrylic or methacrylic acid and less than 50% by weight of polymerized maleic acid or maleic anhydride 20 9. The composition of claim 1 v-'herein said polymer has a weight average molecular weight in the range of from about 2,000 to 25,000. 10. The composition of claim 9 wherein said polymer has a 25 weight average molecular weight in the range of from about 3,000 to 10,000. 11. The composition of claim 1 wherein R is an alkyl group containing from about 6 to 18 carbon atoms. 30 12. The composition of claim 11 wherein R is dodecyl 13. The composition of claim 1 wherein from about 25 to 95% by weight of the hydrophilic polymer chains present in said 3 5 deflocculating polymer composition have said structure P-QR. WO 96/17919 26 PCT/US95/15591 14 The composition of claim 1 wherein said deflocculating polymer composition contains an alkyl sulfide terminated polymer represented by the following structural formula. fl- lL R-j R, H -H wherein R is a straight or branched chain primary, secondary, or tertiary alkyl group having 5 to 20 carbon atoms, R\ and R3 are each hydrogen, methyl, ethyl, or—COOH; R2 and R4 are each hydrogen, methyl, ethyl, —COOH, or —CH2COOH, Y is selected from 10 the group consisting of —COOH, —CONH2, —OCH3, —OC2H5, and —CH2OH; X is selected from the group consisting of —COOC2H4OH, —COOQ3K6OH, —GONHCH2OH, —CONHCH3, —CONHC2H5, —GONHC3H7, —COOCH3, — COOC2H5, —CN, — OOCCH3, —OOCC2H5, and —COOCH3CHOCH2; the degree of polymerization, a+b, is from 2 to 50, 15 and the mole fraction of the monomer having the X functional group, a/(a+b) is from 0 to 0.6 20 15. The composition of claim 1 wherein said deflocculating polymer composition contains an alkyl sulfoxide or alkyl sulfone- terminated polymer represented by the following structural formula: O R, Ri S Rq X / R. 1 1 J H v ^ 1 ■H wherein R is a straight or branched chain primary, secondary, or 25 tertiary alkyl group having 5 to 20 carbon atoms; Ri and R3 are each hydrogen, methyl, ethyl, or—COOH; R2 and R4 are each hydrogen, methyl, ethyl, —COOH, or —CH2COOH, Y is selected from the group consisting of —COOH, —CONH2, —OCH3, —OC2H5, and WO 96/17919 27 PCT/US95/15591 —CH20H; X is selected from the group consisting of —COOC2H4OH, —COOC3H6OH, —CONHCH2OH, —CONHCH3, —CONHC2H5, --OONHC3H7, —COOCH3, —COOC2H5, —CN, —OOCCH3, — OOCC2H5, and —COOCH3CHOCH2; the degree of polymerization, a+b, is from 2 to 50, 5 and the mole fraction of the monomer having the X functional group, a/(a+b) is from 0 to 0.6, and Z is either oxygen or not present such that when Z is oxygen the end-cap group is an alkyl sulfone and when Z is not present the end-cap group is an alkyl sulfoxide 10 16 The composition of claim 1 wherein said detergent builder is present in said composition at a level of from about 15 to 60% by weight of said composition. 17 The composition of claim 16 wherein said detergent 15 builder comprises one or more phosphates 18. The composition of claim 16 wherein said detergent builder comprises a zeolite. 20 19. The composition of claim 16 wherein said detergent builder comprises an alkali metal citrate. 20. The composition of claim 16 wherein said detergent builder comprises an alkali metal carbonate. 25 21. The composition of claim 16 wherein said detergent builder is an alkali metal silicate. 22 The composition of claim 1 containing 15% by weight 30 water or less. 23. A process for preparing a concentrated granular detergent composition comprising: 35 a) forming a crutcher slurry by mixing at least one organic surfactant, at least one detergent builder, water and a deflocculating polymer composition containing polymer chains of the structure P-QR, wherein P represents a polymer WO 96/17919 PCT/US95/15591 28 chain segment of a hydrophilic polymer and QR represents a hydrophobic end-cap group wherein R is an organic hydrophobic radical containing from about 4 to 28 carbon atoms, and Q is selected from the group consisting of O, C02, S, 5 SO, S02, NR\ P04R', PQ3R\ Si OR'R", Si R'R", CR'OH, CR'R" and CR'OR" wherein R1 and R" are each hydrogen, an alkyl group containing from 1 to 4 carbon atoms or an aryl group, said crutcher slurry comprising lamellar droplets of said surfactant dispersed in the aqueous phase and having a viscosity in the 1 0 range of from about 2,000 to 500,000 cps , and b) subjecting said slurry to spray dry conditions to produce a granulated detergent having a water content of about 15% by weight or less and a content of deflocculating polymer in the 15 range of from about 0 01 to about 7.5% by weight 24. The process of claim 23 wherein said slurry contains from about 15 to 50% by weight of surfactant 2 0 25 The process of claim 23 wherein said slurry has a viscosity in the range of about 100,000 to 500,000 cps. 26 The process of claim 25 wherein said viscosity is in the range of about 200,000 to 400,000 cps. 25 27. The process of claim 23 wherein said slurry has a solids content in the range of about 35 to 65% by weight 28. The process of claim 27 wherein said solids content is in 30 the range of about 50 to 65% by weight 29. The process of claim 23 wherein said hydrophilic polymer chain segment P is polyacrylic or polymethacrylic acid. 35 30. The process of claim 23 wherein said hydrophilic polymer chain segment P is a copolymer containing at least 50% by weight of polymerized acrylic or methacrylic acid and less than 50% by weight of polymerized maleic acid or maleic anhydride WO 96/17919 29 PCT/US95/15591 31. The process of claim 23 wherein said polymer has a weight average molecular weight in the range of from about 2,000 to 25,000. 5 32 The process of claim 31 wherein said polymer has a weight average molecular weight in the range of from about 3,000 to 10,000. 33. The process of claim 23 wherein from about 25 to 95% by 10 weight of the hydrophilic polymer chains present in said deflocculating polymer composition have the structure P-SR 34. The process of claim 33 wherein R is an alkyl group containing from about 6 to 18 carbon atoms. 15 35. The process of claim 34 wherein R is dodecyl 298600 30 36 A concentrated granular detergent composition as claimed in claim 1, substantially as herein described with reference to any example thereof END or CLAIMS I to ITIlLIII ImL 11 J,L, n. OF Iu - 3 MAR 1999 RPPPIVfO 101879*1 WON </div>