AU754500B2

AU754500B2 - Detergent and descaling composition tablets and use in dishwasher and washing machine

Info

Publication number: AU754500B2
Application number: AU58697/99A
Authority: AU
Inventors: Francisco Javier Dupuy Arnau; Patrick Ferlin
Original assignee: Rhodia Chimie SAS
Current assignee: Rhodia Chimie SAS
Priority date: 1998-10-09
Filing date: 1999-10-01
Publication date: 2002-11-21
Anticipated expiration: 2019-10-01
Also published as: RU2213132C2; AU5869799A; WO2000022090A1; CN1323342A; HK1042109A1; FR2784392A1; ZA200102369B; FR2784392B1; EP1119606A1

Description

DETERGENT OR DESCALING COMPOSITION TABLETS AND THEIR USE IN DISHWASHERS AND WASHING MACHINES The present invention relates to tablets of compacted particles of a detergent or descaling composition; these tablets can be used for carrying out washing in a washing machine or dishwasher.

Any discussion of the prior art throughout the specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.

It is known practice to prepare detergent .compositions in the form of tablets which have a fast speed of disintegration and dissolution in an aqueous medium, by compacting particles comprising sodium tripolyphosphate (NaTPP), the said NaTPP consisting of at least 40% phase I and containing from 0.5% to 5% by weight of homogeneously distributed water of hydration (EP-A-839 906) The Applicant has found that the presence of a larger amount of water in NaTPP consisting mainly of phase I makes it possible to avoid the transfer of water present in the tablet to this NaTPP, thus preventing the risks of heating of the tablet with disintegration of the sensitive constituents, in particular such as the enzymes.

In addition, the presence of a larger amount of water makes it possible to multiply the number of seeds of hydrated NaTPP and thus helps the tablet to disintegrate Sand dissolve.

A first aspect of the invention provides tablets of a detergent or descaling composition comprising compacted particles based on sodium tripolyphosphate with a high content of phase I and water distributed homogeneously in the said sodium tripolyphosphate, wherein said sodium tripolyphosphate present in the tablet or in the region of the tablet contains from 70% to 100%, by weight of phase I relative to all of the anhydrous sodium tripolyphosphate phases, contains from 7% to 16% of its weight of water, at least 50% of this water being in the form of water of crystallization.

In a preferred embodiment, the tablets contain from 80% to 98% by weight of phase I relative to all of the anhydrous sodium tripolyphosphate phases.

In another preferred embodiment, the tablets contain from 8% to 12% of its weight of water.

In a still further preferred embodiment, from 20 to 90% of the water is in the form of water of crystallization.

The said sodium tripolyphosphate containing from to 100% by weight of phase I and from 7% to 16% water can represent from 5% to 100%, preferably from about 10% to 90%, by weight (expressed as solids) relative to the weight of the tablet (as solids) or of the region of the tablet in which this sodium tripolyphosphate is located.

The NaTPP, consisting at least in the majority of phase I used to prepare the tablets of the invention, can be obtained according to a three-step process: spray-drying of a sodium orthophosphate liquor, calcination to NaTPP anhydride phase I and hydration.

The spray-drying step can be carried out in a known manner, for example with the aid of a nozzle sprayer or a turbomixer sprayer, using a sodium orthophosphate liquor having a solids content which can be from about 50% to 70%, preferably about 60% by weight, and a gas-generating component, in particular ammonium carbonate, injected into the orthophosphate liquor at the spraying head; the amount of ammonium carbonate introduced may be from about 0.1 to 0.6 by weight (expressed as solids) per 100 parts of orthophosphate (expressed as solids).

The inlet temperature of the attacking gases depends on the size of the atomizer and on the fluid flow rates; this temperature can be from about 5000C to 6000C.

The gas outlet temperature can be between 120 0 C and 2000C, preferably between 1400C and 160 0

C.

The orthophosphate particles thus obtained generally have a residual moisture content of less than by weight; their density is from about 0.25 g/cm 3 to 0.45 g/cm 3 preferably about 0.35 g/cm 3 their median diameter is generally between 200 Im and 400 Am; preferably about 300 Am.

The calcination operation can be carried out in a known manner, for example in a co-current directflame rotating oven, the product being cooled immediately after calcination.

The sodium orthophosphate introduced can be calcined over about 30 minutes to one hour, up to a temperature of 450 0 C to 600 0 C, preferably from 490 0 C to 530 0

C.

The product thus obtained is an NaTPP powder consisting in the majority of phase I (from about to 100%); it has a particle size of about 250 Am to 450 Am, preferably of about 350 Am; its density is from about 0.4 g/cm 3 to 0.65 g/cm 3 preferably about 0.55 g/cm 3 The NaTPP powder is then hydrated by spraying with water, for example in a drum, a fast mixer or a fluidized bed, fitted with pulverizers of two-fluid nozzle type generating droplets of about 20 Am to 300 jm, preferably of about 100 jm, until a water content ("water of hydration") of the NaTPP in the particles of about 7% to 16% is obtained. This water content is preferably from about 8% to 12%.

The density of the product is less than or equal to 0.8 g/cm 3 preferably from 0.45 g/cm 3 to 0.65 g/cm 3 According to a first embodiment, this hydration step is carried out by spraying with an aqueous solution of a base or of a basic salt, such as sodium hydroxide, potassium hydroxide, aqueous solutions of alkali metal silicates, of sodium tripolyphosphate, etc. Mention may be made in particular of spraying with an aqueous NaTPP solution preferably containing less than 20 ppm of Ca or Mg, so as to form "nuclei" of NaTPP-6H 2 0.

A second embodiment variant consists in carrying out the hydration step by spraying with an aqueous solution of a wetting agent, for instance nonionic surfactants such as polyethoxylated fatty alcohols, or of a sequestering agent such as salts of polyacetic acids (ethylenediaminetetraacetates, etc.) and polyphosphonates (ethane l-hydroxy-l,1diphosphonates, methylenediphosphonate salts, etc.).

According to one variant of the invention, the said tablets also comprise at least one other sodium tripolyphosphate, for example a sodium tripolyphosphate with a phase I content of less than or a tripolyphosphate consisting in the majority or totally of phase II.

Most particularly, the said other sodium tripolyphosphate is a sodium tripolyphosphate with a phase II content of at least 70% relative to all of the anhydrous sodium tripolyphosphate phases, and a water content which can range from 0% to 15%, preferably from about 5% to The said other sodium tripolyphosphate may be present in the tablets of the invention in an amount such that the total amount of NaTPP in the tablets is from about 5% to 100%, preferably from 10% to depending on the desired use.

The tablets which form the subject of the invention can be detergent tablets for washing machines or dishwashers, as well as descaling tablets.

They can comprise one, two or even more regions.

When they are tablets comprising two regions, the said sodium tripolyphosphate containing from 70% to 100% by weight of phase I and from 7% to 16% water is preferably located in the two regions of the tablet.

When they are washing machine tablets, the amount of the said sodium tripolyphosphate containing from 70% to 100% by weight of phase I and from 7% to 16% water can represent from 5% to 80% by weight, preferably from about 10% to 60% by weight (expressed as solids), relative to the weight of the tablet (as solids) or of the region of the tablet in which this sodium tripolyphosphate is located.

Among the other additives which may be present in the washing machine tablets, mention may be made of sodium tripolyphosphates with a phase I content of less than 70%, or tripolyphosphates consisting in the majority or totally of phase II, in particular tripolyphosphates consisting of at least 70% phase II relative to all of the anhydrous phases, and having a water content of from 0 to 15%, preferably from about to 10%; these sodium tripolyphosphates can be present in the tablets in an amount such that the total amount of NaTPP in the tablets is from about 5% to preferably from 10% to organic or other inorganic detergent adjuvants ("builders"), in an amount which can be up to 50% by weight, these adjuvants being such as alkanolamine, ammonium or alkali metal hexametaphosphates, tetraborates or borate precursors amorphous or crystalline alkali metal silicates alkali metal carbonates the cogranulates of alkali metal silicate hydrates and of alkali metal (sodium or potassium) carbonates rich in silicon atoms, in Q2 or Q3 form, described in EP-A-488,868, for detergent compositions in powder form crystalline or amorphous aluminosilicates of alkali metals (sodium, potassium) or of ammonium, such as zeolites A, P, X, etc.

water-soluble polyphosphonates (ethane l-hydroxy-l,1-diphosphonates, methylene diphosphonate salts, etc.) water-soluble salts of carboxylic polymers or copolymers such as water-soluble salts of polycarboxylic acids with a molecular mass of about 2000 to 100,000, obtained by polymerization or copolymerization of ethylenically unsaturated carboxylic acids such as acrylic acid, maleic acid or anhydride, fumaric acid, itaconic acid, mesaconic acid, citraconic acid or methylenemalonic acid, and most particularly polyacrylates with a molecular mass of about 2000 to 10,000 (US-A-3,308,067), and copolymers of acrylic acid and of maleic anhydride with a molecular mass of about 5000 to 75,000 (EP-A-66915) polycarboxylate ethers (oxydisuccinic acid and its salts, monosuccinic acid tartrate and its salts, disuccinic acid tartrate and its salts) hydroxypolycarboxylate ethers citric acid and its salts, mellitic acid, and succinic acid and their salts polyacetic acid salts (ethylenediamine tetraacetates, nitrilotriacetates and N-(2hydroxyethyl) nitrilodiacetates) Cs-C20-alkyl succinic acids and their salts (2-dodecenyl succinates, lauryl succinates, etc.) polyacetal carboxylic esters polyaspartic acid, polyglutamic acid and their salts polyimides derived from the polycondensation of aspartic acid and/or glutamic acid polycarboxymethylated derivatives of glutamic acid [such as N,N-bis(carboxymethyl)glutamic acid and its salts, in particular the sodium salts] or of other amino acids anionic or nonionic surfactants, in an amount from about 5% to 40% by weight, these agents being such as anionic surfactants (in amounts from about 0% to for instance alkyl ester sulphonates of formula R-CH(SO 3

M)-COOR',

where R represents a Cs-2 0 preferably C10-C16, alkyl radical, R' represents a C 1

-C

6 preferably C 1

-C

3 alkyl radical and M represents an alkali-metal (sodium, potassium, lithium) cation, an ammonium cation which is substituted or unsubstituted (methyl-, dimethyl-, trimethyl-, tetramethylammonium, dimethylpiperidinium, etc.) or an alkanolamine derivative (monoethanolamine, diethanolamine, triethanolamine, etc.); alkyl sulphates of formula ROSO 3 M, in which R represents a Cs-C 24 preferably Clo-C 18 alkyl or hydroxyalkyl radical, M representing a hydrogen atom or a cation of the same definition as above, as well as the ethoxylenated (EO) and/or propoxylenated (PO) derivatives thereof, having on average from 0.5 to preferably from 0.5 to 10, EO and/or PO units; alkylamide sulphates of formula RCONHR'OSO 3 M in which R represents a C 2

-C

22 preferably C 6

-C

20 alkyl radical, R' represents a C 2

-C

3 alkyl radical, M representing a hydrogen atom or a cation of the same definition as above, as well as the ethoxylenated (EO) and/or propoxylenated (PO) derivatives thereof, having on average from 0.5 to 60 EO and/or PO units; saturated or unsaturated C 8

-C

24 preferably C 14

-C

20 fatty acid salts, C 9

-C

2 0 alkylbenzene sulphonates, primary or secondary C 8

-C

22 alkyl sulphonates, alkylglycerol sulphonates, the sulphonated polycarboxylic acids described in GB-A-1,082,179, paraffin sulphonates, N-acyl-N-alkyl taurates, alkyl phosphates, isethionates, alkyl succinamates, alkyl sulphosuccinates, sulphosuccinate monoesters or diesters, N-acylsarcosinates, alkylglycoside sulphates and polyethoxycarboxylates; the cation being an alkali metal (sodium, potassium, lithium), an ammonium residue which is substituted or unsubstituted (methyl-, dimethyl-, trimethyl-, tetramethylammonium, dimethylpiperidinium, etc.) or an alkanolamine derivative (monoethanolamine, diethanolamine, triethanolamine, etc.); sophorolipids, such as those in acid or lactone form, derived from 17-hydroxyoctadecenoic acid; nonionic surfactants, (in amounts from about 0% to for instance polyoxyalkylenated (polyethoxyethylenated, polyoxypropylenated, polyoxybutylenated) alkylphenols in which the alkyl substituent is C 6

-C

12 and containing from 5 to 25 oxyalkylene units; by way of example, mention may be made of Triton X-45, X-114, X-100 or X-102 sold by Rohm Haas Co. and Igepal NP2 to NP17 from Rhone-Poulenc; polyoxyalkylenated C 8

-C

22 aliphatic alcohols containing from 1 to 25 oxyalkylene (oxyethylene, oxypropylene) units; by way of example, mention may be made of Tergitol 15-S-9, Tergitol 24-L-6 NMW sold by Union Carbide Corp., Neodol 45-9, Neodol 23-65, Neodol 45-7, Neodol 45-4 sold by Shell Chemical Co., Kyro EOB sold by The Procter Gamble Co., Synperonic A3 to A9 from ICI, Rhodasurf IT, DB and B from Rh6ne-Poulenc and Plurafac LF 403 sold by BASF; Sproducts resulting from the condensation of ethylene oxide or propylene oxide with propylene glycol or ethylene glycol, with a weight-average molecular mass of about 2000 to 10,000, such as the Pluronic products sold by BASF; products resulting from the condensation of ethylene oxide or propylene oxide with ethylenediamine, such as the Tetronic products sold by BASF; ethoxylated and/or propoxylated C 8

-C

18 fatty acids containing from 5 to 25 ethoxylated and/or propoxylated units;

C

8

-C

2 0 fatty acid amides containing from 5 to ethoxylated units; ethoxylated amines containing from 5 to ethoxylated units; alkoxylated amidoamines containing from 1 to preferably from 1 to 25, and most particularly from 2 to 20, oxyalkylene (preferably oxyethylene) units; amine oxides such as C 10

-C

18 alkyl dimethylamine oxides, C 8

-C

22 alkoxy ethyldihydroxyethylamine oxides; alkoxylated terpenic hydrocarbons such as ethoxylated and/or propoxylated a- or 3-pinenes, containing from 1 to 30 oxyethylene and/or oxypropylene units; alkylpolyglycosides which can be obtained by condensation (for example by acid catalysis) of glucose with primary fatty alcohols (US-A-3,598,865; US-A-4,565,647; EP-A-132,043; EP-A-132,046, etc.) having a C 4

-C

20 preferably C 8

-C

18 alkyl group, as well as an average number of glucose units of about 0.5 to 3, preferably of about 1.1 to 1.8, per mole of alkylpolyglycoside (APG); mention may be made in particular of those having a C 8

-C

14 alkyl group and on average 1.4 glucose units per mole a C 12

-C

14 alkyl group and on average 1.4 glucose units per mole a C 8

-C

14 alkyl group and on average 1.5 glucose units per mole a C8-C 10 alkyl group and on average 1.6 glucose units per mole sold respectively under the names Glucopon 600 EC7, Glucopon 600 CSUP7, Glucopon 650 EC7 and Glucopon 225 CSUP7 by Henkel; antisoiling agents, in amounts of about 0.01-10%, preferably of about 0.1-5% and most particularly of about by weight, these agents being such as cellulose derivatives such as cellulose hydroxy ethers, methylcellulose, ethylcellulose, hydroxypropyl methylcellulose and hydroxybutyl methylcellulose, polyvinyl esters grafted onto polyalkylene trunks, such as polyvinyl acetates grafted onto polyoxyethylene trunks (EP-A-219,048) polyvinyl alcohols polyester copolymers based on ethylene terephthalate and/or propylene terephthalate and polyoxyethylene terephthalate units, with an ethylene terephthalate and/or propylene terephthalate (number of units)/polyoxyethylene terephthalate (number of units) molar ratio from about 1/10 to 10/1, the polyoxyethylene terephthalate units having polyoxyethylene units with a molecular weight from about 300 to 10,000, with a molecular mass of the copolyester from about 1000 to 100,000 polyester copolymers based on ethylene terephthalate and/or propylene terephthalate and polyoxyethylene and/or polyoxypropylene units, with an ethylene terephthalate and/or propylene terephthalate (number of units)/polyoxyethylene and/or polyoxypropylene (number of units) molar ratio from about 1/10 to 10/1, the polyoxyethylene and/or polyoxypropylene units having a molecular weight from about 250 to 10,000, with a molecular mass of the copolyester from about 1000 to 100,000 (US-A-3 959 230, US-A-3 962 152, US-A-3 893 929, US-A-4 116 896, US-A-4 702 857, US-A-4 770 666, EP-A-253 567, EP-A-201 124) ethylene or propylene terephthalate/polyoxyethylene terephthalate copolymers comprising sulphoisophthaloyl units in their chain (US-A-4 711 730; US-A-4 702 857; US-A-4 713 194) terephthalic copolyester oligomers with sulphonated polyalkenoxyalkyl and sulphoaroyl end groups and optionally containing sulphoisophthaloyl units in their chain (US-A-4 721 580; US-A-5 415 807; US-A-4 877 896; US-A-5 182 043; US-A-5 599 782; US-A-4 764 289; EP-A-311 342; WO 92/04433; WO 97/42293) sulphonated terephthalic copolyesters with a molecular mass of less than 20,000, for example obtained from a diester of terephthalic acid or of isophthalic acid or from a diester of sulphoisophthalic acid and of a diol, in particular ethylene glycol (WO 95/32997) polyester-polyurethanes obtained by reaction of a polyester with a number-average molecular mass of 300-4000 obtained from a terephthalic acid diester, optionally from a diester of sulphoisophthalic acid and of a diol, with a prepolymer containing isocyanate end groups obtained from a polyoxyethylene glycol with a molecular mass of 600-4000 and from a diisocyanate (US-A-4 201 824) sulphonated polyester oligomers obtained by sulphonation of an oligomer derived from ethoxylated allyl alcohol, from dimethyl terephthalate and from 1,2-propylene diol, containing from 1 to 4 sulphonated groups (US-A-4 968 451); anti-redeposition agents, in amounts of about 0.01-10% by weight for a detergent composition in powder form, these agents being such as ethoxylated monoamines or polyamines and ethoxylated amine polymers (US-A-4 597 898, EP-A-11 984) carboxymethylcellulose sulphonated polyester oligomers obtained by condensation of isophthalic acid, dimethyl sulphosuccinate and diethylene glycol (FR-A-2 236 926) polyvinylpyrrolidones bleaching agents, in an amount of about 0.1-20%, preferably 1-10%, of the weight of said detergent composition in powder form, such as perborates such as sodium perborate monohydrate or tetrahydrate peroxygenated compounds such as sodium carbonate peroxyhydrate, pyrophosphate peroxyhydrate, urea peroxyhydrate, sodium peroxide and sodium persulphate percarboxylic acids and their salts (known as percarbonates") such as magnesium monoperoxyphthalate hexahydrate, magnesium metachloroperbenzoate, 4-nonylamino-4-oxoperoxybutyric acid, 6-nonylamino-6-oxoperoxycaproic acid, diperoxydodecanedioic acid, peroxysuccinic acid nonylamide and decyldiperoxysuccinic acid, preferably combined with a bleaching activator generated in situ in the washing medium, a peroxycarboxylic acid; among these activators, mention may be made of tetraacetylethylenediamine, tetraacetylmethylenediamine, tetraacetyl glycoluryl, sodium p-acetoxybenzene sulphonate, pentaacetyl glucose, octaacetyl lactose, etc.

fluorescence agents, in an amount of about 0.05-1.2% by weight, these agents being such as derivatives of stilbene, pyrazoline, coumarin, fumaric acid, cinnamic acid, azoles, methinecyanins, thiophenes, etc.

foam suppressants, in amounts which can be up to 5% by weight, these agents being such as

C

10

-C

24 monocarboxylic fatty acids or their alkali-metal, ammonium or alkanolamine salts, and fatty acid triglycerides saturated or unsaturated aliphatic, alicyclic, aromatic or heterocyclic hydrocarbons, such as paraffins or waxes, N-alkylaminotriazines monostearyl phosphates and monostearyl alcohol phosphates polyorganosiloxane oils or resins optionally combined with silica particles softeners, in amounts of about 0.5-10% by weight, these agents being such as clays enzymes in an amount which can be up to 5 mg by weight, preferably about 0.05-3 mg, of active enzyme/g of detergent composition, these enzymes being such as proteases, amylases, lipases, cellulases and peroxidases (US-A-3 553 139, US-A-4 101 457, US-A-4 507 219, US-A-4 261 868) and other additives such as alcohols (methanol, ethanol, propanol, isopropanol, propanediol, ethylene glycol and glycerol) buffers or fillers such as sodium sulphate, alkalineearth metal carbonates or bicarbonates pigments disintegrating agents compacting agents such as polyethylene glycols.

When they are dishwasher tablets, the amount of the said sodium tripolyphosphate containing from to 100% by weight of phase I and from 7% to 16% water can represent from 10% to 90% by weight (expressed as solids) relative to the weight of the tablet (as solids) or of the region of the tablet in which this sodium tripolyphosphate is located.

Among the other additives which may be present in the dishwasher tablets, mention may be made of sodium tripolyphosphates with a phase I content of less than 70%, or tripolyphosphates consisting in the majority or totally of phase II, in particular tripolyphosphates consisting of at least 70% phase II relative to all of the anhydrous phases, and having a water content of from 0% to 15%, preferably from about to 10%; these sodium tripolyphosphates can be present in the tablets in an amount such that the total amount of NaTPP in the tablets is from about 20% to other basifying additives or sequestering additives that are soluble in the washing medium, for instance alkanolamine, ammonium or alkali metal hexametaphosphates tetraborates or borate precursors alkali metal silicates to 30% by weight) *alkali metal carbonates to 30% by weight) Sthe cogranulates of alkali metal silicate hydrates and of alkali metal (sodium or potassium) carbonates rich in silicon atoms, in Q2 or Q3 form, described in EP-A-488,868, for detergent compositions in powder form crystalline or amorphous aluminosilicates of alkali metals (sodium, potassium) or of ammonium, such as zeolites A, P, X, etc.

water-soluble polyphosphonates (ethane l-hydroxy-l,1-diphosphonates, methylene diphosphonate salts, etc.) water-soluble salts of carboxylic polymers or copolymers such as water-soluble salts of polycarboxylic acids with a molecular mass of about 2000 to 100,000, obtained by polymerization or copolymerization of ethylenically unsaturated carboxylic acids such as acrylic acid, maleic acid or anhydride, fumaric acid, itaconic acid, mesaconic acid, citraconic acid or methylenemalonic acid, and most particularly polyacrylates with a molecular mass of about 2000 to 10,000 (US-A-3,308,067), copolymers of acrylic acid and of maleic anhydride with a molecular mass of about 5000 to 75,000 (EP-A-66915) polycarboxylate ethers (oxydisuccinic acid and its salts, monosuccinic acid tartrate and its salts, disuccinic acid tartrate and its salts) *hydroxypolycarboxylate ethers citric acid and its salts, mellitic acid, succinic acid and their salts polyacetic acid salts (ethylenediamine tetraacetates, nitrilotriacetates and N-(2hydroxyethyl) nitrilodiacetates) Cs-C 20 -alkyl succinic acids and their salts (2-dodecenyl succinates, lauryl succinates, etc.) Spolyacetal carboxylic esters Spolyaspartic acid, polyglutamic acid and their salts polyimides derived from the polycondensation of aspartic acid and/or glutamic acid polycarboxymethylated derivatives of glutamic acid [such as N,N-bis(carboxymethyl)glutamic acid and its salts, in particular the sodium salts] or of other amino acids alkali metal bicarbonates and sesquicarbonates bleaching agents such as alkali metal perborates and percarbonates to 20%) combined with a bleaching activator (tetraacetylethylenediamine) (up to 10%) and optionally combined with a bleaching catalyst (organometallic complexes of manganese, cobalt, etc.) to 1%) nonionic surfactants to for instance Spolyoxyalkylenated (polyethoxyethylenated, polyoxypropylenated or polyoxybutylenated) alkylphenols in which the alkyl substituent is C6-C 12 and containing from 5 to 25 oxyalkylene units; by way of example, mention may be made of Triton X-45, X-114, X-100 or X-102 sold by Rohm Haas Co. and Igepal NP2 to NP17 from Rh6ne-Poulenc; Spolyoxyalkylenated C 8

-C

22 aliphatic alcohols containing from 1 to 25 oxyalkylene (oxyethylene or oxypropylene) units; by way of example, mention may be made of Tergitol 15-S-9 and Tergitol 24-L-6 NMW sold by Union Carbide Corp., Neodol 45-9, Neodol 23-65, Neodol 45-7 and Neodol 45-4 sold by Shell Chemical Co., Kyro EOB sold by The Procter Gamble Co., Synperonic A3 to A9 from ICI, Rhodasurf IT, DB and B from Rh6ne-Poulenc, and Plurafac LF 403 sold by BASF; products resulting from the condensation of ethylene oxide or of propylene oxide with propylene glycol or ethylene glycol, with a weight-average molecular mass of about 2000 to 10,000, such as the Pluronic products sold by BASF; products resulting from the condensation of ethylene oxide or of propylene oxide with ethylenediamine, such as the Tetronic products sold by

BASF;

ethoxylated and/or propoxylated Cs-Cs 1 fatty acids containing from 5 to 25 ethoxylated and/or propoxylated units;

C

8

-C

20 fatty acid amides containing from to 30 ethoxylated units; ethoxylated amines containing from 5 to ethoxylated units; alkoxylated amidoamines containing from 1 to 50, preferably from 1 to 25 and most particularly from 2 to 25, oxyalkylene units (preferably oxyethylene units); amine oxides such as (C 10 -Cis) alkyldimethylamine oxides and (C 8

-C

22 alkoxyethyldihydroxyethylamine oxides; alkoxylated terpenic hydrocarbons such as ethoxylated and/or propoxylated a- or P-pinenes, containing from 1 to 30 oxyethylene and/or oxypropylene units; anionic surfactants to enzymes to 4%) dyes, fragrances tablet-compacting agents, such as polyethylene glycols, or tablet-disintegrating agents.

When they are descaling tablets, the amount of the said sodium tripolyphosphate containing from to 100% by weight of phase I and from 7% to 16% water can represent from 10% to 100% by weight, preferably from 20% to 90% by weight (expressed as solids), relative to the weight of the tablet (as solids) or of the region of the tablet in which this sodium tripolyphosphate is located.

Among the other additives which may be present in the descaling tablets, mention may be made of sodium tripolyphosphates with a phase I content of less than 70%, or tripolyphosphates consisting in the majority or totally of phase II, in particular tripolyphosphates consisting of at least 70% phase II relative to all of the anhydrous phases, and having a water content of from 0% to 15%, preferably from about to 10%; these sodium tripolyphosphates can be present in the tablets in an amount such that the total amount of NaTPP in the tablets is from about 30% to 99%, preferably from 50% to sodium hexametaphosphate to amorphous or crystalline alkali metal silicates (0% to alkali metal carbonates to amorphous or crystalline ammonium or alkali metal aluminosilicates to water-soluble polyphosphonates (ethane-l-hydroxy-l,1diphosphonates, methylenediphosphonate salts, etc.) (0% to water-soluble salts of carboxylic polymers or copolymers to such as water-soluble salts of polycarboxylic acids with a molecular mass of about 2000 to 100,000, obtained by polymerization or copolymerization of ethylenically unsaturated carboxylic acids such as acrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, mesaconic acid, citraconic acid or methylenemalonic acid, and most particularly polyacrylates and copolymers of acrylic acid and of maleic anhydride surfactants to A second aspect of the invention provides a process for preparing the tablets according to the first aspect by pressing the desired amount of a particulate 15 composition in a mould, this composition containing the various constituents of the said tablets. The density of the tablets may be from about 0.9 g/cm 3 to 2 g/cm 3 depending on the desired use.

Unless the context clearly requires otherwise, 20 throughout the description and the claims, the words 'comprise', 'comprising', and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of "including, but not limited to".

The examples which follow are given as a guide.

24a Examples 1-10 The following are introduced into an industrial Niro atomizer equipped with a turbomixer 3 m 3 /h of sodium orthophosphate liquor with a solids content of 61% by weight, at a temperature of 90 0

C

S**

OO0•O

BO

•gig g

O

O•O

o e o o 0.3 part by weight (as solids) of ammonium carbonate per 100 parts by weight (as solids) of sodium orthophosphate.

The gas inlet temperature is 500 0 C; the outlet temperature is 150 0 C. The product obtained, with a density of 0.35 g/cm 3 is then calcined up to 520 0 C in a co-current direct-flame rotating oven.

The NaTPP obtained has the following characteristics: a phase I content of 87% relative to all of the anhydrous phases a density of 0.55 g/cm 3 A portion of the product is hydrated in an industrial drum by spraying it with water, so as to obtain an NaTPP having different degrees of "hydration": 3.3% water, 54% of this water being in the form of water of crystallization 4.4% water, 62% of this water being in the form of water of crystallization 8% water, 74% of this water being in the form of water of crystallization Examples 1, 2 and 3, respectively.

Another portion is not hydrated (Example 4) A third portion is hydrated batchwise in a Lbdige high-speed blender, by spraying it with water, so as to obtain an NaTPP with different degrees of "hydration": 4% water, 63% of this water being in the form of water of crystallization 8% water, 75% of this water being in the form of water of crystallization 10% water, 78% of this water being in the form of water of crystallization Examples 5, 6 and 7, respectively.

A fourth portion is hydrated by spraying it with water continuously in a Comessa fluidized bed (from Comessa), for which the flow rate of powder is from 50 kg/h to 100 kg/h, so as to obtain an NaTPP with different degrees of "hydration": 4% water, 8% water, 10% water, Examples 8, 9 and 10, respectively.

Test 1 31.5 g of non-hydrated or hydrated NaTPP of Examples 4 to 7 are compacted without further modification, using a Zwick 14 78 00/01 press, the force applied being 2.4 knewtons, to form cylindrical tablets 41 mm in diameter.

Each tablet is placed on a screen (mesh size of 2 mm) immersed in 9 litres of demineralized water at 220C, with stirring (200 rpm) S T The dissolution speed (DS) of each tablet is determined by monitoring the conductivity of the water.

The time required for 90% of the tablet to dissolve is thus determined.

The results are given in Table 1.

Test 2 parts of NaTPP of Examples 1 to 3, 5-6 and 8 to 10 are mixed with 70 parts of a washing base containing: 11% alkylbenzene sulphonate 5% nonionic surfactant 30% phase NaTPP of Examples 1-3, 5-6 and 8-10 10% NaTPP of LV brand sold by Europhos 7% atomized and granulated silicate of ratio R2 6% sodium carbonate 15% sodium percarbonate 4% TAED 2% of an antifoaming agent (granulated) 2% Sokalan CP5 from BASF 4% enzymes and fragrance 31.5 g of each mixture are compacted, the force applied being 1.6 knewtons or 2.4 knewtons, to form cylindrical tablets 41 mm in diameter.

The dissolution speed and the longitudinal breaking tension t in pascals are measured for each tablet.

r z ioC; The longitudinal breaking tension t is given by the equation t 2F/7De, in which F is the force applied, in newtons D is the diameter of the tablet, in metres e is the thickness of the tablet, in metres.

The results are given in Table 2.

TABLE 1 NaTPP of Degree of Force applied DS90 in Example "hydration" in kN minutes in 4 -0 2.4 16 4 2.4 4 6 8 2.4 2 7 10 2.4 0.6 TABLE 2 NaTPP Degree of Force DS90 t of Example "hydration" applied in minutes in kPa in in kN 1 3.3 1.6 6.7 9.9 2.4 9.3 15.2 2 4.4 1.6 4 9.9 2.4 5.2 15.3 3 8 1.6 2.6 10.3 2.4 4.2 23 4 1.6 3.7 19.0 2.4 5.6 32.4 6 8 1.6 2.7 19.2 2.4 3.9 33.1 8 4 2.4 4.4 25.7 9 8 2.4 3 25.5 10 2.4 3.2 27.3

Claims

1. Tablets of a detergent or descaling composition comprising compacted particles based on sodium tripolyphosphate with a high content of phase I and water distributed homogeneously in the said sodium tripolyphosphate, wherein said sodium tripolyphosphate present in the tablet or in the region of the tablet contains from 70% to 100%, by weight of phase I relative to all of the anhydrous sodium tripolyphosphate phases, contains from 7% to 16% of its weight of water, at least 50% of this water being in the form of water of crystallization. S: 2. Tablets according to Claim 1, containing 15 from 80% to 98% by weight of phase I relative to all of the anhydrous sodium tripolyphosphate phases.

3. Tablets according to Claim 1 or Claim 2, wherein from 70% to 90% of the water is in the form of o water of crystallization. 20 4. Tablets according to any one of Claims 1 to 3, wherein the said sodium tripolyphosphate containing from to 100% by weight of phase I and from 7% to 16% of water represents from 5% to 100%, by weight (expressed as solids) relative to the weight of the tablet (as solids) or of the region of the tablet in which this sodium tripolyphosphate is located. Tablets according to Claim 4, wherein the Ssaid sodium tripolyphosphate containing from 70% to 100% by weight of phase I and from 7% to 16% of water represents from about 10% to 90%, by weight (expressed as solids) relative to the weight of the tablet (as solids) or of the region of the tablet in which this sodium tripolyphosphate is located.

6. Tablets according to any one of Claims 1 to wherein the said sodium tripolyphosphate containing from to 100% by weight of phase I contains from about 8% to 12% water.

7. Tablets according to any one of Claims 1 to 6, wherein the said sodium tripolyphosphate containing from 70% to 100% by weight of phase I has a density of less than *9 or equal to 0.8 g/cm 3

8. Tablets according to Claim 7, wherein the *9 density is from 0.45 g/cm 3 to 0.65 g/cm 3

9. Tablets according to any one of Claims 1 to 8, also comprising at least one other sodium tripolyphosphate. 9.

10. Tablets according to Claim 9, wherein the 20 said sodium tripolyphosphate is a sodium tripolyphosphate with a phase I content of less than 70% and/or a tripolyphosphate consisting in the majority or totally of phase II.

11. Tablets according to Claim 9 or Claim wherein the said other sodium tripolyphosphate is a sodium tripolyphosphate with a phase II content of at least relative to all of the anhydrous sodium tripolyphosphate /V y\phases, and a water content which can range from 0% to

12. Tablets according to Claim 11, wherein the water content can range from about 5% to

13. Tablets according to Claim 11 or Claim 12, wherein the said other sodium tripolyphosphate is present in the tablets in an amount such that the total amount of sodium tripolyphosphate in the tablets is from about 5% to 100%.

14. Tablets according to Claim 13, wherein the amount of sodium tripolyphosphate in the tablets is from 10 10% to Tablets according to any one of Claims 1 to 14, wherein they are detergent tablets for washing machines or dishwashers, or descaling tablets.

16. Tablets according to any one of Claims 1 to 15 15, wherein they are washing machine tablets, in which the amount of the said sodium tripolyphosphate containing from to 100% by weight of phase I and from 7% to 16% water represents from 5% to 80% (expressed as solids) relative to the weight of the tablet (as solids) or of the region of the tablet in which this sodium tripolyphosphate is located.

17. Tablets according to Claim 16, wherein they are washing machine tablets, in which the amount of the said sodium tripolyphosphate containing from 70% to 100% by weight of phase I and from 7% to 16% water represents from about 10% to 60% (expressed as solids), relative to the weight of the tablet (as solids) or of the region of the Stablet in which this sodium tripolyphosphate is located.

18. Tablets according to Claim 16 or Claim 17, also containing a sodium tripolyphosphate consisting of at least 70% of phase II relative to all of the anhydrous phases and having a water content of from 0% to 15%, in an amount such that the total amount of sodium tripolyphosphate in the tablets is from about 5% to

19. Tablets according to Claim 18, wherein the water content is from 5% to

20. Tablets according to Claim 18 or Claim 19, .10 wherein the amount of sodium tripolyphosphate in the tablets is from about 10% to

21. Tablets according to any one of Claims 1 to wherein they are dishwasher detergent tablets, in which the amount of the said sodium tripolyphosphate containing from 70% to 100% by weight of phase I and from 7% to 16% water represents from 10% to 90% by weight (expressed as solids) relative to the weight of the tablet (as solids) or Sof the region of the tablet in which this sodium tripolyphosphate is located.

22. Tablets according to Claim 21, also containing a sodium tripolyphosphate consisting of at least phase II relative to all of the anhydrous phases and having a water content of from 0% to 15%, in an amount such that the total amount of sodium tripolyphosphate in the tablets is from about 20% to

23.Tablets according to Claim 22, wherein the water content is from about 5% to

24. Tablets according to any one of Claims 1 to wherein they are dishwasher detergent tablets, in which the amount of the said sodium tripolyphosphate containing from 70% to 100% by weight of phase I and from 7% to 16% water represents from 10% to 100%, by weight (expressed as solids), relative to the weight of the tablet (as solids) or of the region of the tablet in which this sodium tripolyphosphate is located.

25. Tablets according to Claim 24, wherein they *i 10 are dishwasher detergent tablets, in which the amount of the said sodium tripolyphosphate containing from 70% to 100% by weight of phase I and from 7% to 16% water represents from 20% to 90%, by weight (expressed as solids), relative to the weight of the tablet (as solids) 15 or of the region of the tablet in which this sodium tripolyphosphate is located.

26. Tablets according to Claim 24 or Claim o •also containing a sodium tripolyphosphate consisting of at least 70% phase II relative to all of the anhydrous phases and having a water content of from 0% to 15%, in an amount such that the total amount of sodium tripolyphosphate in the tablets is from about 30% to 99%.

27. Tablets according to Claim 26, wherein the water content is from about 5% to

28. Tablets according to Claim 26 or Claim 27, wherein the amount of sodium tripolyphosphate in the tablets is from about 50% to

29. Process for preparing the tablets forming the subject of any one of the preceding claims, by pressing the desired amount of a particulate composition in a mould, this composition containing the various constituents of the said tablets. Tablets of a detergent or descaling composition, substantially as herein described with reference to any one of the examples but excluding comparative examples. S* 10 31. Process for preparing tablets of a detergent or descaling composition, substantially as herein described with reference to any one of the examples but excluding comparative examples. DATED this 18 t h Day of September 2001 15 RHODIA CHIMIE Attorney: PAUL G. HARRISON Fellow Institute of Patent and Trade Mark Attorneys of Australia of BALDWIN SHELSTON WATERS