MXPA06007931A - Tablets with improved resistance to breakage - Google Patents

Abstract

The invention relates to a process for making a detergent tablet, comprising the steps of:(a) selecting a binder from:sorbitol, xylitol, erythritol, C10-C18 phenol alkoxylates with 20 to 80 equivalents of alkoxylation;C12-C24 alcohol alkoxylates with 50 to 250 equivalents of alkoxylation;castor oil alkoxylates with 50 to 100 equivalents of alkoxylation;mono-, di- and/or tri-esters of glycerin with C12-C25 fatty acids;C10 to C25 fatty acids;and mixtures thereof;(b) heating the binder to above its melting point to form a molten binder;(c) applying the molten binder to a base powder comprising a premix of detergent components, to form a detergent composition;and (d) forming the detergent composition into tablets. The present invention is further directed to a tablet composition obtainable by such process and to the use of such a binder, in its molten form for improving the resistance to breakage of a detergent tablet.

Description

TABLETS WITH GREATER RESISTANCE TO BREAKAGE FIELD OF THE INVENTION The present invention relates to compositions in tablet form, especially tablets for automatic washing of garments or crockery with a greater resistance to breakage. These pellets are obtained by means of a process in which a specific fused binder is applied to a base powder.

BACKGROUND OF THE INVENTION Compositions in tablet form, for example for the automatic washing of garments or crockery are increasingly popular with consumers as they allow them to be supplied in unit dosages and are easy to store and handle. For detergent manufacturers, the tablet compositions also offer many advantages such as lower transport, handling and storage costs. However, one of the usual problems of the use of tablet compositions lies in their reduced dimensional stability and resistance to breakage and their frequent instability in the face of abrasion. Tablet compositions are often not suitable for packaging, shipping and handling requirements, that is, when they are dropped or worn. Consequently, broken edges and visible abrasion of the pills affect their appearance or even cause their structure to be completely destroyed. One option to solve this problem is the use of relatively high pressure when compressing the particulate materials that make up the tablet. However, this leads to a severe densification of the components of the tablet and often produces a reduced or delayed disintegration of the tablet in the washing liquid with all the drawbacks associated therewith, such as a lower cleaning performance and others. Tablets having a reduced disintegration profile can not be placed in the drawer of domestic washing machines, since they do not disintegrate sufficiently rapidly into secondary particles small enough to pass from the detergent drawer to the washing drums. Another method for increasing the stability of tablet compositions is the use of a binder. The detergent tablets can be prepared by contacting a compact detergent powder with a binder and the subsequent tabletting of the powder to form the tablet. The binder acts as an adherent in the powder detergent and allows to apply a lower pressure when forming the tablet. EP 971 028 (P &G, published January 12, 2000) discloses a tablet formed by compressing conventional detergent ingredients with a binder such as alkali metal C3-C8 alkyl and dialkylaryl sulfonates. The most commonly used binder material is polyethylene glycol (PEG). The PEG agglutinates the compact detergent powder in the proper way. The document EP 1 352 951 (P &G, published October 15, 2003) discloses a tablet detergent composition with a binder system for spraying comprising PEG. Sugars have also been used as binders. EP 1 138 756 (Henkel, published on October 4, 2001) describes sugar binders that are incorporated as a dry aggregate to a base powder. The resulting mixture is granulated and subsequently compressed to form the detergent tablet. DE 101 25 441 (Henkel, published December 5, 2002) illustrates premixtures containing sugar, compressed and subsequently heated. U.S. Pat. no. No. 4,642,197 (Henkel, published February 10, 1987) discloses an aqueous solution of 70% sorbitol that is sprayed onto a base powder prior to forming the tablet by compression. In view of the current high demands related to handling and fast transport, pills with greater physical strength are required. Therefore, one of the objects of the present invention is to provide a tablet composition with greater physical integrity, for example with greater resistance to breakage, while maintaining excellent profiles of dissolution and dispatch. The inventors have found that a tablet obtained by means of a process in which a specific fused binder is applied to a base powder exhibits that higher breaking strength and at the same time maintains optimal dissolution and dispatch profiles. Another advantage of the present invention is that the pads with optimum breaking strength can be produced with an interval of density greater than that which can be obtained with common binders. This provides pellets with an improved dissolution profile.

BRIEF DESCRIPTION OF THE INVENTION In a first embodiment of the present invention there is provided a process for making a detergent tablet comprising the steps of: (a) Selecting a binder of: sorbitol, xylitol, erythritol, C 10 -C 18 alkoxylates of phenol with 20 to 80 equivalents of alkoxylation; C12-C24 alcohol alkoxylates with 50 to 250 alkoxylation equivalents; Castor oil alkoxylates with 50 to 100 alkoxylation equivalents; mono, di and triesters of glycerin with C12-C25 fatty acids; C10 to C25 fatty acids and mixtures thereof; (b) heating the binder to a temperature above its melting point to form a molten binder; (c) applying the molten binder to a base powder comprising a premix of detergent components to form a detergent composition; and (d) forming the detergent composition into tablets. In a second embodiment of the present invention, a tablet composition obtainable by means of the aforementioned process is provided.

In a third embodiment of the present invention, there is provided the use of a molten binder to improve the strength of the detergent tablet at break; the binder is selected from: sorbitol, xylitol, erythritol, C10-C18 alkoxylates of phenol with 20 to 80 equivalents of alkoxylation; C12-C24 alcohol alkoxylates with 50 to 250 alkoxylation equivalents; Castor oil alkoxylates with 50 to 100 alkoxylation equivalents; mono, di and triesters of glycerin with C12-C25 fatty acids; fatty acids from C10 to C25 and mixtures of these.

DETAILED DESCRIPTION OF THE INVENTION Unless specifically indicated otherwise, all figures referring to quantities, percentages, portions and proportions are modified by the word "approximately" and do not intend to indicate fixed digits. As used in the present invention, the term "alkoxylation" includes the use of any linear, branched, substituted or unsubstituted alkoxy group, generally C to C10 alkoxy groups and mixtures thereof. Preferred alkoxy groups are selected from ethoxy, propoxy, butoxy and mixtures thereof; especially ethoxy is preferred. As used in the present invention, the term "unsubstituted" means that the hydrocarbon chain contains only carbon and hydrogen atoms and no other heteroatoms except, where appropriate, the hydroxy group that forms the alcohol functional group. As used in the present invention, the term "substituted" means that the hydrocarbon chain also contains atoms other than carbon and hydrogen atoms. The substituted hydrocarbon chains may also contain heteroatoms as one or more nitrogen atoms, phosphorus, sulfur, fluorine, chlorine, bromine, iodine and any other atom of the periodic table of the elements.

The process The process of the present invention, referred to herein as "process" is used to prepare a composition in tablet form. It comprises the steps of: (a) selecting a binder of: sorbitol, xylitol, erythritol, C 10 -C 18 alkoxylates of phenol with 20 to 80 alkoxylation equivalents; C12-C24 alcohol alkoxylates with 50 to 250 alkoxylation equivalents; Castor oil alkoxylates with 50 to 100 alkoxylation equivalents; mono, di and triesters of glycerin with C12-C25 fatty acids; C10 to C25 fatty acids and mixtures thereof; (b) heating the binder to a temperature above its melting point to form a molten binder; (c) applying the molten binder to a base powder comprising a premix of detergent components to form a detergent composition; and (d) forming the detergent composition into tablets.

In the present invention it is essential to heat the binder system to a temperature above its melting point, by means of any heating system, to form a molten binder system before applying said system to the base powder. The binder system comes into contact with the base powder to form a composition in the proper form. In general, this contact occurs at a minimum temperature of 45 ° C, preferably from 55 ° C to 150 ° C, and more preferably from 70 ° C to 120 ° C. Such contact generally occurs when spraying the molten binder system onto the base powder. In general, this step of the process is carried out using a spray arm, preferably a spray arm in a rotating spray drum. Preferred spray arms include at least one nozzle, preferably more than one nozzle, for example 10 to 18 nozzles connected to a low pressure hot air line. Low pressure refers to a pressure less than 700 kNm "2, preferably between 100 kNm" 2 and 600 kNm "2, more preferably between 150 kNm'2 and 550 kNm" 2 and most preferably 200 kNm "2 at 450 kNm "2. The temperature of the hot air is generally at least 45 ° C, preferably from 55 ° C to 160 ° C and more preferably from 70 ° C to 120 ° C. The tableting of this composition is then performed, usually by means of compression or compaction to form a detergent tablet. This compression / compaction step is generally carried out in a conventional tablet press, for example a normal one-hit press or a rotary press such as Courtoy, Korch, anesthesia or Bonals.

Preferably, the force used in this compression / compaction step is generally less than 100,000 N, preferably less than 50,000 N, or even less than 5,000 N, or even less than 3,000 N. Most preferably, the process of present invention includes a step of compressing or compacting the composition with a force of less than 2500 N. The automatic dishwashing detergent tablets can be compressed or compacted with a force greater than 2500 N, if necessary. Other steps of the compaction process can be used, including for example, agglomerate or extrusion. The diameter of the detergent tablet usually varies between mm and 60 mm and the weight varies between 10 g and 100 g. The height / width ratio of the pads is usually greater than 1: 3. The density of the pellets is generally at least 900 g / l, preferably at least 950 g / l, and preferably less than 2000 g / l, more preferably less than 1500 g / l, most preferably less than 1200 g / l. In a preferred embodiment of the present invention, the detergent tablet is generally coated with a coating material. This material generally comes into contact with the rest of the detergent tablet at a minimum temperature of 40 ° C, preferably at least 100 ° C, more preferably at least 140 ° C, and most preferably at a temperature from 150 ° C to 170 ° C. Preferred coating materials contain a combination of (i) a dicarboxylic acid and (ii) a clay or ion exchange resin. An ion exchange resin preferred is PG2000Ca distributed by Purolite. Preferred dicarboxylic acids are selected from oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebasic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid, derivatives thereof or combinations of these; Adipic acid is especially preferred. Preferably, the weight ratio of components (i) to (ii) above is included in the range of from 40: 1 to 10: 1, and more preferably from 30: 1 to 20: 1. When a coating material is included, its amount usually varies from 1% to 10% and more preferably from 4% to 8% by weight of the detergent tablet. In a preferred embodiment of the present invention, the detergent tablet has multiple layers of the same or different colors. Especially preferred are multilayer bars having 2 or 3 layers. Also included in the present invention are multi-layer or single-layer pellets having projections, cavities or holes of any geometric shape. Especially preferred are pads with incorporated geometric shapes such as hemispheres, which protrude from their surface. In general, the binder concentration is from 0.1% to 80%, preferably from 0.5% to 30%, more preferably from 1.0% to 10% and most preferably from 1.25% to 5% by weight of the detergent tablet . In general, the concentration of the base powder ranges from 20% to 99.9%, preferably from 35% to 99%, more preferably from 50% to 98.5%, and most preferably from 55 to 95% by weight of the detergent tablet.

Binder The molten binder may contain a part of undissolved material, but most of the molten binder is liquid under the processing conditions described above, for example at least 80% by weight, or at least 85% by weight, or at least 90% by weight, or at least 95% by weight of the binder is liquid under the mentioned processing conditions. Preferably, all the binder is liquid under these conditions. Suitable binders for use in the processes of the present invention are selected from: sorbitol, xylitol, erythritol, C 10 -C 18 alkoxylates of phenol with 20 to 80 alkoxylation equivalents; C12-C24 alcohol alkoxylates with 50 to 250 equivalents of alkoxylation; Castor oil alkoxylates with 50 to 100 alkoxylation equivalents; mono, di and triesters of glycerin with C12-C25 fatty acids; fatty acids of C10 to C25 and mixtures of these. The preferred binders are selected from: sorbitol; xylitol erythritol; nonylphenol, ethoxylate 50 (distributed as Berol 291 ex Akzo Nobel) alcohol C16-C22, ethoxylate 80 (distributed as Berol 08 ex Akzo Nobel) castor oil, ethoxylate 160 (distributed as Berol 198 ex Akzo Nobel) glyceryl tripalmitin ester (distributed as former Sigma-Aldrich); stearic acid (distributed as ex Sigma-Aldrich); C16-C18 alcohol, ethoxylate 80 (distributed as ex Clariant); alcohol of C13-C15, ethoxylate 30 (distributed as Lutensol AO30 ex BASF) and mixtures thereof. The especially preferred binder is sorbitol.

Optionally, the binder of the present invention can be mixed with one or more additional compounds to form a binder system. These additional compounds can be selected from a wide variety of different ingredients. Suitable ingredients can be selected from viscosity modifiers, additive agents, dissolution aids, surfactants, fabric softening agents, alkalinity sources, dyes, perfumes, lime soap dispersants, organic polymeric compounds including polymeric ink transfer inhibiting agents , crystalline growth inhibitors, heavy metal ion sequestrants, metal ion salts, corrosion inhibitors, softening agents, optical brighteners and combinations of these. Preferred ingredients are viscosity modifiers, dissolution aids, surfactants, alkalinity sources, dyes, perfumes, crystalline growth inhibitors and combinations thereof. A particularly preferred additional component is a viscosity modifier. When a viscosity modifier is included, its concentration varies from 1.0% to 95%, preferably from 2.5% to 50%, more preferably from 5.0% to 15% and most preferably from 7.5% to 12.5% by weight of the binder system. Suitable viscosity modifiers can be aqueous or non-aqueous and can include only water or organic solvents or combinations of these. Preferred organic solvents include linear, branched, cyclic, substituted or unsubstituted monohydric, dihydric and linear polyhydric alcohols, ethers, ethers alkoxylates, low viscosity silicone-containing solvents, low-melting and optionally alkoxylated non-ionic surfactants having a melting point of less than 45 ° C and combinations thereof. More preferably, they include glycerin, glycols, linear, branched, cyclic, substituted or unsubstituted polyalkylene glycols such as polyalkylene glycols, dialkylene glycol mono C6 ethers, non-ionic C5-C15 surfactants with 1 to 10 equivalents of ethoxylation, monohydric alcohols, dihydric alcohols , and combinations of these. With an even greater preference, they include diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether and combinations thereof. Most preferably they include linear, branched, cyclic, substituted or unsubstituted short chain aliphatic alcohols such as ethanol, propanol, butanol, isopropanol and diols such as 1,2-propanediol, 1,3-propanediol, 1,6-hexanediol, 1,2-hexanediol, 2-ethyl-1,3-hexanediol, 2-methyl-2,4-pentanediol, 2,3,4-trimethyl-1,3-pentanediol, 1,4-bis (hydroxymethyl) cyclohexane and combinations of these, optionally with dialkylene glycol mono ethers of glycols and water. The especially preferred viscosity modifier is water alone or a 50:50 mixture of water with glycerin or C12-C15 nonionic surfactant with 3 to 7 equivalents of ethoxylation or 1,2-propanediol, 1,3-propanediol, 1, 6-hexanediol, 1,2-hexanediol, 2-ethyl-1,3-hexanediol. 2-methyl-2,4-pentanediol, 2,3,4-trimethyl-1,3-pentanediol, 1,4-bis (hydroxy) cyclohexane, and combinations thereof. When water is used as a viscosity modifier, alone or in combination with other viscosity modifiers, the The total water content is preferably up to 20%, more preferably up to 10% and most preferably between 3% and 7% by weight of the binder system. In this case, it is not intended to use an aqueous solution of one or more binders. More preferably, the binder system contains sorbitol and between 3% and 7% water of the viscosity modifier, by weight. The binder of the present invention can also be used to bind in the particle-making processes, for example agglomeration, compaction, granulation, spray-drying, extrusion. Base powder Base powder usually contains a variety of different ingredients such as additive agents, effervescent system, enzymes, dissolving aids, disintegrants, bleaching agents, foam suppressors, surfactants (non-ionic, anionic, cationic, amphoteric, or zwitterionic), fabric softening agents, alkalinity sources, dyes, perfumes, soap dispersants of lime, organic polymeric compounds including dye transfer inhibition polymeric agents, crystalline growth inhibitors, antiredeposit agents, stain release polymers, hydrotropes, fluorescers, heavy metal ion sequestrants, metal ion salts, enzyme stabilizers, inhibitors of corrosion, softening agents, optical brighteners and combinations of these.

In general, the base powder is a preformed detergent granule.

This granule can be an agglomerated particle or it can be presented in some other form. "Agglomerated particle" usually refers to a previously agglomerated particle and is therefore already in that state before contact with the molten binder as described above. In general, the average particle size of the base powder is 100 μm to 2000 μm, preferably 200 μm, or 300 μm, or 400 μm or 500 μm, preferably 1800 μm, or 1500 μm, or at 1200 μm, or 1000 μm, or 800 μm, or 700 μm. Most preferably, the average particle size of the base powder is 400 μm to 700 μm. In general, the bulk density of the base powder is 400 g / l, 200 g / l, preferably from 500 g / l to 950 g / l, more preferably from 600 g / l to 900 g / l, and with the maximum preference of 650 g / l to 850 g / l. Preferred optional ingredients are described hereinafter in more detail. All percentages are expressed based on the weight of the entire detergent tablet, unless otherwise specified. Preferred Optional Ingredients Additive Compound Here, the base powder preferably contains an additive compound, usually at a concentration of 1% to 80%, preferably 10% to 70% and most preferably 20% to 60% in weight of the base powder.

Especially preferred additive compounds for use in the present invention are the water soluble phosphate additives. Specific examples of water-soluble phosphate additives are the tripolyphosphates of alkali metals, sodium pyrophosphate, potassium and ammonium, sodium and potassium orthophosphate, polymeta / sodium phosphate with a degree of polymerization of 6 to 21 and salts of phytic acid. Examples of partially water soluble additives include the layered crystalline silicates such as those described for example in EP-A-0164514, DE-A-3417649 and DE-A-3742043. Examples of water insoluble additives include sodium aluminosilicates. Suitable aluminosilicates include aluminosilicate zeolites whose unit cell has the formula Naz [(AI02) z (SiO2) and] - H20 where z and y are at least 6; the molar ratio of z to y is from 1.0 to 0.5 and x is at least 5, preferably from 7.5 to 276, more preferably from 10 to 264. The aluminosilicate material is in hydrated form and preferably is crystalline and contains 10% to 28%, with more preference of 18% to 22% of water in linked form. Effervescent System Preferably, the base powder herein contains an effervescent system, usually at a concentration of 1% to 30%, preferably 5% to 25% and most preferably 10% to 20% by weight of the base powder.

Effervescent systems suitable herein include those derived from the combination of an acid source and a bicarbonate or carbonate or from the combination of hydrogen peroxide and catalase or any combination of materials that releases small gas bubbles, for example dioxide gas. of carbon. The components of the effervescent system can be dispensed in combination to form effervescence upon mixing or can be formulated together whenever conventional coatings or protection systems are used. Hydrogen peroxide and catalase are very effective and can be included with much lower concentrations producing excellent results. Surfactant The base powder of the present preferably contains at least one surfactant, preferably two or more. The total concentration of surfactant generally ranges from 1% to 80%, preferably from 10% to 70% and most preferably from 20% to 60% by weight of the base powder. Suitable surfactants are selected from anionic, cationic, nonionic, ampholytic and zwitterionic surfactants and mixtures thereof. A typical list of the classes and species of the anionic, nonionic, amphoteric and zwitterionic surfactants is included in U.S. Pat. no. 3,929,678 issued to Laughiin and Heuring on December 30, 1975. A list of suitable cationic surfactants is included in U.S. Pat. no. 4,259,217 issued to Murphy on March 31, 1981. A list of the surfactants generally used in the compositions Laundry detergents are included for example in EP-A-0414 549 and in PCT applications nos. WO 93/08876 and WO 93/08874. Other suitable active detergent compounds are fully included and described in WO 02/31100 published on April 18, 2002 and assigned to P &G and in the literature, for example in "Surface-active agents and detergents" (Surface Agents and Detergents) active), Vol. I and II by Schwartz, Perry and Berch. Dissolving aid Preferably, the base powder of the present contains a dissolving aid, usually at a concentration of 0.01% to 10%, preferably from 0.1% to 5% and most preferably from 0.15% to 2.5% in weight of the base powder. The solution aid may preferably contain a sulphonated organic compound such as alkenyl and C 4 alkyl sulphonic acids and C 4 alkyl alkylsulfonic acids or derivatives, salts or combinations thereof. Preferably, the dissolution aid may contain salts of arylsulfonic acids, including the alkali metal salts of benzoic acid, salicylic acid, benzenesulfonic acid, naphthoic acid, derivatives and combinations thereof. Preferred examples of arylsulfonic acid salts are the sodium, potassium and ammonium benzene sulphonate salts derived from toluenesulfonic acid, xylene sulfonic acid, eumenal sulphonic acid, tetralin sulfonic acid, naphthalenesulfonic acid, methyl naphthalene sulfonic acid, dimethyl naphthalene sulfonic acid and trimethyl acid. Naphthalene sulphonic Especially the sodium toluenesulfonate, sodium cumene sulphonate, sodium xylene sulfonate, derivatives and combinations thereof. The solution aid may contain dialkylbenzenesulfonic acid salts such as diisopropyl benzene sulphonic acid salts, ethyl methyl benzene sulphonic acid, alkylbenzenesulfonic acid with a linear or branched C3-C10 alkyl chain, preferably C4-C9. The dissolution aid may contain a C 4 C alcohol such as methanol, ethanol, propanol such as isopropanol and derivatives and combinations thereof, preferably ethanol and isopropanol. The solution aid may contain a C4-C10 diol such as hexanediol or cyclohexanediol, preferably 1,6-hexanediol or 1,4-cyclohexanedimethanol. The dissolving aid may contain a compound comprising a chemical group of the following general formula - wherein E is a hydrophilic functional group, R is H or a C 10 alkyl group or a hydrophilic functional group, R 1 is H or an alkyl group of C, -C 10 or an aromatic group, R 2 is H or a cyclic alkyl or an aromatic group. The number average molecular weight of the compound is preferably from 1,000 to 1,000,000.

The dissolution aid may contain 5-carboxy-4-hexyl-2-cyclohexen-1-yl octanoic acid. The dissolution aid may contain a cationic compound. Preferably, it contains a cationic polymer, more preferably an ethoxylated cationic diamine. Preferred ethoxylated cationic diamines correspond to the general formula; X- L- L- X (R3) d R3 (XL) 2- M2- R? - M2- R2 _? _ wherein M ^ is a group N + or N, preferably a group N +; each M2 is a group N + or N, preferably a group N + and at least one M2 is a group N +; R is H or C4 alkyl or hydroxyalkyl; R is alkylene, hydroxyalkylene, alkenylene, arylene or C2-C12 alkarylene or a C2-C3 oxyalkylene entity having between 2 and 20 oxyalkylene units as long as they are not formed O-H links; each R2 is alkyl or hydroxyalkyl of C ^ C ^ the entity L-X or two R2 together form the entity (CH2) r-A2- (CH2) s, where A2 is O or CH2, r is 1 or 2, s is 1 or 2 and r + s is 3 or 4; each R3 is C8 alkyl or hydroxyaicyl, benzyl, the entity LX or two R3 or one R3 and R2 together form the entity (CH2) r-A2- (CH2) s, wherein A2 is O or CH2, r is 1 or 2, s is 1 or 2 and r + s is 3 or 4; X is a non-ionic group selected from H, alkyl or hydroxyalkyl ester or alkyl groups, and mixtures thereof, among the esters and ethers are preferred acetate ester and methyl ether, respectively; L is a hydrophilic chain containing the polyoxyalkylene entity. { (R60) m (CH2CH20) n} wherein R6 is C3-C4 alkylene or hydroxyalkylene, m and n are numbers such that the (CH2CH2O) n entity contains at least 50% of the polyoxyalkylene entity by weight; d is 1 when M2 is N + and 0 when M2 is N; n is at least 6. The positive charge of the N + groups is compensated by the appropriate number of counter-anions. Suitable counter-anions include Cl ", Br", S032", SO42", PO42", MeOS03" and the like. Especially CI "and Br are preferred. A preferred ethoxylated cationic diamine suitable for use herein is the one known under the tradename Lutensit K-HD 96 distributed by BASF.Smobilizing ingredient Optionally, the base powder of the present invention may contain a softening ingredient, usually with a concentration of 0. 5% to 50%, preferably from 1% to 30% and most preferably from 5% to 20% by weight of the base powder. Suitable softening ingredients for use herein may be selected from any known ingredient that provides fabric softening benefits, for example, smectite clay. The smectite clays used herein are those usually distributed. These clays include, for example, montmorillonite, volchonskoite, nontronite, hectorite, saponite, sauconite and vermiculite. The clays herein are distributed under different trade names, for example Thixogel # 1® and Gelwhite GP® by Georgia Kaolin Co., Elizabeth, New Jersey; Volclay BC® and Volclay n # 325® by American Colloid Co., Skokie, Illinois; Black Hills Bentonite BH450® by International Minerals and Chemicals and Veegum Pro and Veegum F by R.T. Vanderbilt It should be recognized that those smectite-type minerals distributed under the aforementioned trade names may include mixtures of the various different mineral parts. These mixtures of smectite minerals are suitable for use herein. Smectite clays are described in U.S. Pat. num. 3,862,058, 3,948,790, 3,954,632 and 4,062,647. European patents no. EP-A-299,575 and EP-A-313,146 in the name of Procter and Gamble Company describe suitable organic polymer clay flocculating agents.

Enzymes When enzymes are included, they are selected from cellulase, hemicellulases, peroxidases, proteases, glucoamylases, amylases, xylanases, lipases, phospholipases, esterases, cutinases, pectinases, keratanases, reductases, oxidases, phenoloxidases, lipoxygenases, ligninases, pullulanases, tanases, pentosanas, malanases, ß-glucanases, arabinosidases, hyaluronidase, chondroitinase, laccase or mixtures thereof. Preferred enzymes include protease, amylase, lipase, peroxidases, cutinase or cellulase together with one or more enzymes that degrade the plant cell wall. In general, the enzymes are incorporated in the detergent tablets with a concentration of 0.0001% to 2% of active enzyme by weight of the base powder. Enzymes can be added as separate individual ingredients (nuggets, granulates, stable fusions, etc. that contain an enzyme) or as mixtures of two or more enzymes (eg granulates). Bleaching agents Optionally, the base powder of the present may contain materials selected from metal catalyst complexes, activated sources of peroxide compound, bleach activators, bleach boosters, photobleaches, free radical initiators and hypohalite bleach. Examples of suitable metal catalyst complexes include, but are not limited to, manganese-based catalysts such as Mn? V2 (u-0) 3 (1, 4,7-trimethyl-1, 4,7-triazacyclononane) 2 ( PF6) 2 described in U.S. patent no. 5,576,282, cobalt-based catalysts described in U.S. Pat. no. 5,597,936 as cobalt pentamino acetate salts corresponding to the formula [Co (NH3) 5OAc] Ty > where "OAc" represents an acetate entity and "Ty" is an anion; Transition metal complexes of a rigid macropolicíclico ligand, abbreviated as "MRL". Suitable metals in MRLs include Mn, Fe, Co, Ni, Cu, Cr, V, Mo, W, Pd and Ru in their various oxidation states. Examples of suitable MRLs include: dichloro-5, 12-diethyl-1,5,8,12-tetraazabicyclo [6.6.2] hexadecane manganese (II), dichloro-5,12-diethyl-1, 5,8,12-tetraaza-bicyclo [6.6.2] hexadecane manganese (III) hexafluorophosphate and dichloro-5-n-butyl-12-methyl-1, 5,8,12-tetraaza-bicyclo [6.6.2] hexadecane manganese (II). Suitable MRLs of transition metals are prepared rapidly by known procedures such as those described, for example, in WO 00/332601 and in U.S. Pat. no. 6,225,464. Suitable activated peroxide compound sources include but are not limited to preformed perishes, a source of hydrogen peroxide combined with a bleach activator or a mixture thereof. Suitable preformed perishes include but are not limited to compounds selected from percarboxylic salts and acids, percarbonic salts and acids, perimidic salts and acids, salts and peroxymonosulfuric acids and mixtures thereof. Suitable sources of hydrogen peroxide include but are not limited to compounds selected from perborate, percarbonate, perphosphate compounds and mixtures thereof. The types and Suitable concentrations of the activated sources of peroxide compound are included in U.S. Pat. num. 5,576,282; 6,306,812 B1; and 6,326,348 B1, incorporated herein by reference. Suitable bleach activators include but are not limited to perhydrolyzable esters and perhydrolysable imides such as tetraacetylethylene diamine, octanoylcaprolactam, benzoyloxybenzenesulfonate, nonanoyloxybenzenesulfonate, benzoylvalerolactam, dodecanoyloxybenzenesulfonate. Suitable bleach builders include but are not limited to those described in U.S. Pat. no. 5,817,614. For practical reasons and not in the form of limitation, the base powder of the present can be adjusted to provide at least about one part in one hundred million of the metal catalyst complex in the aqueous wash. When sources of hydrogen peroxide are included, their approximate concentration generally ranges from 1% to 30% by weight of the base powder. When peracids or bleach activators are included, their approximate concentration usually varies between 0.1% and 60% by weight of the bleaching composition. For practical reasons and not in the form of limitation, the base powder herein can be adjusted to provide at least about one part in one hundred million of the bleach booster in the aqueous wash.

Heavy Metal Ion Sequestering Agent The base powder of the present may contain a heavy metal ion sequestrant as an optional component. By heavy metal ion sequestrant, components that act to sequester (chelate) heavy metal ions are referred to herein. These components may also have chelating capacity for calcium and magnesium, although they preferably show selectivity for binding to heavy metal ions, such as iron, manganese and copper. In general, the concentration of heavy metal ion sequestrants ranges from 0.005% to 20%, preferably from 0.1% to 10%, more preferably from 0.25% to 7.5% and most preferably from 0.5% to 5%. % by weight of the base powder. Water-soluble sulfate salt Optionally, the base powder of the present invention contains a water-soluble sulfate salt. When a water soluble sulfate salt is included its concentration ranges from 0.1% to 40%, more preferably from 1% to 30% and most preferably from 5% to 25% by weight of the base powder. The water soluble sulfate salt can basically be any sulfate salt with any counter cation. The preferred salts are selected from the sulfates of the alkali and alkaline earth metals, especially sodium sulfate.

Alkali metal silicate A preferred component of the base powder herein is an alkali metal silicate. A preferred alkali metal silicate is sodium silicate having a S02: Na20 ratio of 1.8 to 3.0, preferably 1.8 to 2.4 and most preferably 2.0. The concentration of the sodium silicate is preferably less than 20%, more preferably from 1% to 15% and most preferably from 3% to 12% by weight of SiO2. The alkali metal silicate can be in the form of anhydrous or hydrated salt. Foam suppressor systems When the base powder of the present is formulated for use in washing machine compositions, preferably it contains a foam suppressor system with a concentration of 0.01% to 15%, preferably 0.05% to 10% and most preferably from 0.1% to 5% by weight of the base powder. The foam suppressor systems that can be used herein comprise practically any known antifoam compound, including for example, silicone antifoam compounds and 2-alkyl and alkanol antifoam compounds. Preferred foam suppressor systems and antifoam compounds are disclosed in PCT application no. WO93 / 08876 and in EP-A-705 324. Other Optional Ingredients Other optional ingredients suitable for inclusion in the base powder of the invention include perfumes, optical brighteners, dye transfer inhibiting agents and filler salts among which sodium sulfate is preferred.

EXAMPLES All percentages are expressed by weight, unless specified otherwise.

TABLE 1 The values provided in Table 1 are percentages by weight of the entire detergent tablet.

TABLE 2 The values given in Table 2 are percentages by weight of the entire detergent tablet.

Anionic / cationic agglomerates contain 20% to 45% anionic surfactant, 0.5% to 5% cationic surfactant, 0% to 5% TAE80, 15% to 30% SKS6, 10% to 25% of zeolite, from 5% to 15% of carbonate, from 0% to 5% of carbonate, from 0% to 5% of sulphate, from 0% to 5% of silicate, from 0% to 5% of water. The anionic agglomerates contain between 40% and 80% anionic surfactant and between 20% and 60% DIBS. Nonionic agglomerates contain between 20% and 40% of nonionic surfactant, between 0% and 10% of polymer, between 30% and 50% of anhydrous sodium acetate, between 15% and 25% of carbonate and between 5% and 10% zeolite. 6. Clay agglomerates contain between 90% and 100% modified surface clay (CSM) Quest 5A, between 0% and 5% alcohol or diol and between 0% and 5% water.

- The layered silicate contains between 90% and 100% of SKS6 and between 0% and 10% of silicate. - Bleach activator agglomerates 1 contain between 65% and 75% bleach activator, between 10% and 15% anionic surfactant and between 5% and 15% sodium citrate. - The bleach activator agglomerates 2 contain between 75% and 85% of TAED, between 15% and 20% of acrylic / aleic copolymer (acid form) and between 0% and 5% of water. 0- The sulphate / sodium salt of ethylene diamine N, N-disuccinic acid contains between 50% and 60% of the sodium salt of ethylene diamine NN-disuccinic acid, between 20% and 25% of sulphate and between 15% and 25% of Water. 1 - Phthalocyanine zinc sulfonate encapsulates are from 5% to 15% active. ^ - The foam suppressor contains between 10% and 15% silicone oil (ex Dow Corning), between 50% and 70% zeolite and between 20% and 35% water.

EXAMPLE 1 i) Binder A was prepared by heating sorbitol at 105 ° C in a 250 mL beaker (Duran® by Schott Glass / Germany) with a laboratory heating plate distributed by IKA Labortechnik. ii) The base powder E was prepared by mixing the ingredients of the base powder E mentioned in Table 2, in a concrete mixer drum (distributed by LESCHA) at atmospheric pressure and room temperature. iii) 2.4 g of the molten binder A from step i) was sprayed onto 97. 6 g of the base powder E from step ii) at a temperature of 105 ° C and a pressure of 200 kPa to form a composition, iv) The composition was allowed to cool to a temperature of 25 ° C and then the tabletting was performed using a press GEPA. 40 g of composition were placed in a square 41 • 41 mm matrix and the composition was pressed to obtain a detergent tablet with a hardness of 63.74 N as determined in a VK200 tablet hardness tester (distributed by Van Kell Industries, Inc. .).

EXAMPLE 2 i) Binder B was prepared by mixing 28 g of solid sorbitol with 4 g of glycerin before heating the mixtures to 105 ° C in a 250 mL beaker (Duran® from Schott Glass / Germany) with a laboratory heating plate distributed over IKA Labortechnik. The resulting liquid mixture was mixed 10 minutes. ii) The base powder F was prepared by mixing the ingredients of the base powder F mentioned in Table 2, in a concrete mixing drum (distributed by LESCHA) at atmospheric pressure and room temperature. iii) 3.2 g of the molten binder B from step i) was sprayed onto 96.8 g of the base powder F of step ii) at a temperature of 105 ° C and a pressure of 200 kPa to form a composition. iv) The composition was allowed to cool to a temperature of 25 ° C and then tabletting was performed as indicated in Example 1, iv).

EXAMPLE 3 i) The binder C was prepared by mixing 18.8 g of solid sorbitol with 1.2 g of water before heating the mixture until 105 ° C in a 250 mL beaker (Duran® by Schott Glass / Germany) with a laboratory heating plate distributed by IKA Labortechnik. The resulting liquid mixture was mixed 10 minutes, i) Base powder E was prepared as in Example 1, ii). iii) 2.0 g of molten binder C from step i) was sprayed onto 98.0 g of base powder E from step i) at a temperature of 105 ° C and a pressure of 200 kPa to form a composition, iv) The composition was allowed to cool to a temperature of 25 ° C and then the tabletting was performed as indicated in Example 1, iv).

EXAMPLE 4 i) The binder D was prepared by mixing 27 g of solid sorbitol with 2.5 g of water and 2.5 g of glycerin before heating the mixture to 105 ° C in a 250 mL beaker (Duran® from Schott Glass / Germany) with a plate laboratory heater distributed by IKA Labortechnik. The resulting liquid mixture was mixed 10 minutes, ii) The base powder F was prepared as in Example 2, ii). iii) 3.2 g of the molten binder D from step i) was sprayed onto 96.8 g of the base powder F of step ii) at a temperature of 105 ° C and a pressure of 200 kPa to form a composition. iv) The composition was allowed to cool to a temperature of 25 ° C and then tabletting was performed as indicated in Example 1, iv).

EXAMPLE 5 Detergent tablets weighing 40 g each were prepared in accordance with Examples 1 and 3. The detergent tablets are coated with a coating material comprising adipic acid and PG-2000Ca. 2.5 g of coating material was applied to each detergent tablet.

The coating material is prepared by mixing 95 g of adipic acid with 5 g of ion exchange resin such as PG-2000Ca distributed by Purolite at a temperature of 160 ° C.

Claims (11)

NOVELTY OF THE INVENTION CLAIMS

1. A process for making a detergent tablet comprising the steps of: (a) Selecting a binder from the group comprising: sorbitol, xylitol, erythritol, C 10 -C 18 alkoxylates of phenol with 20 to 80 alkoxylation equivalents; C12-C24 alcohol alkoxylates with 50 to 250 alkoxylation equivalents; Castor oil alkoxylates with 50 to 100 alkoxylation equivalents; mono, di and triesters of glycerin with C12-C25 fatty acids; fatty acids from C10 to C25; and mixtures of these; (b) heating the binder to a temperature above its melting point to form a molten binder; (c) applying the molten binder to a base powder comprising a premix of detergent components to form a detergent composition; and (d) forming the detergent composition into tablets.

2. The process according to claim 1, further characterized in that the binder is selected from sorbitol; xylitol; erythritol; nonylphenol, ethoxylated 50; C16-C22 alcohol, ethoxylate 80; Castor oil, ethoxylate 160; glyceryl tripalmitin ester; stearic acid; C16-C18 alcohol, ethoxylate 80; alcohol of C13-C15, ethoxylated 30, and mixtures of these.

3. The process according to any of the preceding claims, further characterized in that the binder is sorbitol.

The process according to any of the preceding claims, further characterized in that the binder is mixed with one or more additional components selected from the group comprising: viscosity modifiers, dissolution aids, surfactants, alkalinity sources, dyes, perfumes, crystalline growth inhibitors, and combinations thereof.

5. The process according to any of the preceding claims, further characterized in that the binder is mixed with a viscosity modifier.

The process according to claims 4 or 5, further characterized in that the concentration of the viscosity modifier is from 1.0% to 95%, more preferably from 2.5% to 50%, even more preferably from 5.0% to 15% , and most preferably from 7.5 to 12.5% by weight of the binder system.

The process according to any of the preceding claims, further characterized in that the binder is sprayed onto the base powder.

The process according to any of the preceding claims, further comprising step (e): (e) Coating the detergent tablet with a coating material.

9. A tablet composition obtained by means of a process defined in any of the preceding claims.

10. A coated tablet composition obtained by means of a process defined in claim 8.

11. The use of a molten binder to improve the strength of the detergent tablet at break; the binder is selected from the group comprising: sorbitol, xylitol, erythritol, C10-C18 alkoxylates of phenol with 20 to 80 equivalents of alkoxylation; C12-C24 alcohol alkoxylates with 50 to 250 alkoxylation equivalents; Castor oil alkoxylates with 50 to 100 alkoxylation equivalents; mono, di and triesters of glycerin with C12-C25 fatty acids; fatty acids from C10 to C25 and mixtures of these.