DE69901211T2 - detergent tablet - Google Patents

Abstract

1. A multi-phase detergent tablet for use in a washing machine, the tablet comprising: a) a first phase in the form of a shaped body having at least one mould therein; and b) a second phase in the form of a compressed body adhesively contained within said mould, wherein the tablet composition comprises one or more detergent actives which is predominantly concentrated in the second phase, and wherein the second phase additionally comprises a binder. The multi-phase tablets provide improved dissolution and cleaning characteristics together with excellent tablet integrity and strength.

Description

Technical area

The present invention relates to multiphase washing or cleaning agent tablets.

background

Detergent compositions in tablet form are known in the art. It is said that detergent compositions in tablet form have numerous advantages over detergent compositions in particulate form, such as ease of dosing, handling, transportation and storage.

Detergent tablets are most commonly made by premixing components of a detergent composition and forming the premixed detergent components into a tablet using any suitable device, preferably a tablet press. Tablets are typically formed by compression of the components of the detergent composition so that the tablets produced are sufficiently robust to withstand handling and transportation without sustaining damage. In addition to being robust, tablets must also dissolve sufficiently rapidly so that the detergent components are released into the wash water as soon as possible at the start of the wash cycle.

However, there is a dichotomy in that as the compression force is increased, the dissolution rate of the tablets is slower. The present invention therefore intends to find a balance between tablet robustness and tablet dissolution.

Solutions to this problem, as proposed in the prior art, have involved compressing the tablets with low compression pressure. However, tablets produced in this way, although they have a exhibit a fast relative dissolution rate, leading to crumbling, becoming defective and unacceptable to the consumer. Other solutions have included preparing tablets using a high relative compression pressure to achieve the required degree of robustness and the use of a dissolution aid such as an effervescent agent.

Multiphase detergent tablets described in the prior art are prepared by compressing a first composition in a tablet press to form a substantially planar first layer. A further detergent composition is then fed to the tablet press on top of the first layer. This second composition is then compressed to form a further substantially planar second layer. Thus, the first layer will generally undergo more than one compression, as it will also be compressed during compression of the second composition. Typically, the first and second compression forces will be of the same order of magnitude. The Applicant has found that where this is the case, as the compression force must be sufficient to bond the first and second compositions together, the force applied in both the first and second compression stages must be in the range of from about 4,000 to about 20,000 kg (assuming a tablet cross-section of about 10 cm²). A consequence of this is a slower tablet dissolution rate. Other multiphase tablets which exhibit different dissolution are manufactured so that the second layer is compressed at a lower force than the first layer. However, although the dissolution rate of the second layer is improved, the second layer is soft compared to the first layer and therefore susceptible to damage caused by handling and transportation.

EP-B-0 055 100 describes a toilet cleaning cube which is formed by combining a slowly dissolving body with a tablet. The toilet cleaning cube is designed to placed in the water tank of a toilet and dissolved over a period of days, preferably weeks. As a means of slowing the dissolution rate of the toilet cleaning cube, this document teaches the addition of one or more solubility regulating agents. Examples of such solubility regulating agents are a para-dichlorobenzene, waxes, long chain fatty acids and alcohols and esters thereof, and fatty alkylamides. Detergent tablets for use in washing or machine dishwashing must dissolve substantially within one cycle of the washing machine or dishwasher, that is, within 15 to 120 minutes.

Summary of the invention

According to a first aspect of the invention there is provided a multiphase detergent tablet for machine dishwashing for use in a washing machine, the tablet having a weight of 15 to 40 g and comprising:

a) a first phase in the form of a shaped body having at least one cavity in its surface; and

b) a second phase in the form of a particulate solid adherent within the hollow form, which has a mass of less than 4 g, wherein the tablet composition comprises one or more detergent active ingredients selected from builders, colorants, surfactants and enzymes, which are predominantly concentrated in the second phase, and wherein the second phase additionally comprises a binder and wherein the tablet is designed such that a differential dissolution of the phases occurs during use.

In preferred embodiments, the first phase is a compressed molded body produced at an applied compression pressure of at least about 3.92 MPa (40 kg/cm²), preferably at least about 24.5 MPa (250 kg/cm²), more preferably at least about 34.3 MPa (350 kg/cm² or 3.43 kN/cm²), even more preferably from about 39.2 (400) to about 196 (2000), and most preferably from about 58.8 (600) to about 117.6 MPa (1,200 kg/cm²) (compression pressure here means the applied force divided by the cross-sectional area of the tablet in a plane perpendicular to the applied force - ultimately the transverse cross-sectional area of the die of the rotary press). It is also preferred that the particulate solid of the second phase (which terminology is intended to include the possibility of multiple "second" phases, sometimes referred to herein as "optional subsequent phases") be compressed into the mold at an applied compression pressure which is less than that applied to the first phase, and preferably at a compression pressure of less than about 34.3 MPa (350 kg/cm2), preferably in the range of from about 3.92 MPa (40 kg/cm2) to about 29.4 MPa (300 kg/cm2), and more preferably from about 6.86 (70) to about 26.5 MPa (270 kg/cm2), such tablets being preferred herein from the viewpoint of providing optimal tablet integrity and strength (e.g., as measured by the Child Bite Strength [CBS] test) and product dissolution characteristics. The tablets of the invention preferably have a CBS of at least about 6 kg, preferably more than about 8 kg, more preferably more than about 10 kg, especially more than about 12 kg, and most preferably more than about 14 kg, where the CBS is measured according to the US Consumer Product Safety Commission Test Specification. Likewise, the compression pressures applied to the first and second phases are generally in a ratio of at least about 1.2:1, preferably at least about 2:1, more preferably at least about 4:1.

Thus, according to a preferred aspect of the present invention, the tablet comprises:

a) a first phase in the form of a compressed molded body having at least one cavity therein, the molded body being manufactured at a compression pressure of at least about 34.3 MPa (350 kg/cm2); and

b) a second phase in the form of a particulate solid compressed within the hollow mould, the second phase being at a pressure of compressed to less than about 34.3 MPa (350 kg/cm²).

The second phase is in the form of a compressed or shaped body which is adherently contained, for example by physical or chemical adhesion, within the at least one hollow form of the first body. It is also preferred that the first and second phases are present in a relatively high weight ratio to one another, for example of at least about 6:1, preferably at least about 10:1; The tablet composition contains one or more detergent active ingredients which are predominantly concentrated in the second phase, for example at least about 50, preferably at least about 60, in particular about 80% by weight of the material (based on the total weight of the active ingredient in the tablet) is present in the second phase of the tablet. Again, such compositions are optimal for tablet strength, dissolution, cleaning and pH control properties, for example providing tablet compositions which are capable of dissolving in the washing liquid so that at least 50, preferably at least 60, and more preferably at least 80% by weight of the detergent actives are released to the washing liquid within 10, 5, 4 or even 3 minutes from the start of the washing process.

Thus, according to a further preferred aspect of the invention, the tablet comprises:

a) a first phase in the form of a shaped body having at least one cavity therein, and

b) a second phase in the form of a particulate solid compressed within the hollow mold, and wherein the tablet comprises at least one detergent active ingredient and is formulated such that at least 50, preferably at least 60, more preferably at least 80% by weight of the detergent active ingredient is released to the laundry within the first 10 minutes, preferably within the first 5 minutes, and more preferably within the first 3 minutes, of the washing process.

An additional advantage of the invention is the ability to achieve differential dissolution of the phases, so that one phase of the tablet dissolves significantly before another phase, and may even dissolve substantially completely before the other phase dissolves. This is particularly valuable in the differential release of detergent actives.

According to a further preferred aspect of the invention, the tablet comprises:

a) a first phase in the form of a shaped body having at least one cavity therein; and

b) a second phase in the form of a compressed body which is adherently contained within the hollow form, wherein the tablet composition comprises one or more detergent active ingredients which are predominantly concentrated in the second phase, and wherein the second phase additionally comprises a binder.

Suitably, the one or more detergent actives are selected from enzymes, bleaches, bleach activators, bleach catalysts, surfactants, complexing agents, crystal growth inhibitors and mixtures thereof, with the enzyme actives being particularly preferred for enhancing the cleaning effectiveness during the very first cold water stage of the washing or cleaning operation. Highly preferred for use herein are therefore enzyme detergent actives and in particular enzymes and enzyme mixtures comprising one or more enzymes with enhanced or optimal activity in the temperature range of 25°C to 55°C and at a pH in the range of 8 to 10 (e.g. Natalase).

Thus, according to yet another preferred aspect of the invention, the tablet comprises:

a) a first phase in the form of a shaped body having at least one cavity therein; and

b) a second phase in the form of a compressed body which adheres contained within the hollow form, and wherein the second phase additionally comprises an enzyme.

Detailed description of the invention

An object of the present invention is to provide a detergent tablet which is not only sufficiently robust to withstand handling and transportation, but also at least a significant portion of which dissolves rapidly in the wash water to provide rapid release of detergent active. It is preferred that at least one phase of the tablet dissolves in the wash water within the first 10 minutes, preferably 5 minutes, more preferably 4 minutes, of the wash cycle of an automatic dishwashing or laundry washing machine. Preferably the washing machine is either an automatic dishwashing or laundry washing machine. The time within which the multiphase tablet or a phase thereof or a detergent active ingredient component dissolves is determined in accordance with DIN 44990 using a dishwasher available from Bosch in a 65ºC normal wash program at a water hardness of 18ºH using at least 6 repetitions or a sufficient number to ensure reproducibility.

The multiphase detergent tablet of the invention comprises a first phase, a second and optionally subsequent or further phases. The first phase is in the form of a shaped body of a detergent composition comprising one or more detergent components as described below. Preferred detergent components include builders, bleaches, enzymes and surfactants. The components of the detergent composition are mixed together, for example by mixing dry components or spraying on liquid components. The components are then formed into a first phase using any suitable device, but preferably by compression, for example in a tablet press. Alternatively, the first Phase can be produced by extrusion, casting, etc. The first phase can take a variety of geometric shapes, such as spheres, cubes, etc., but preferred embodiments have a generally axially symmetrical shape with a generally round, square or rectangular cross-section.

The first phase is manufactured to include at least one cavity in the surface of the molded body. The cavity or cavities may also vary in size and shape and in their location, orientation and topology relative to the first phase. For example, the cavity or cavities may be generally circular, square or oval in cross-section; they may form an internally closed cavity or depression in the surface of the molded body, or they may extend between unconnected regions of the body surface (e.g., axially opposed faces) to form one or more topological "holes" in the molded body; and they may be axially or otherwise symmetrically disposed relative to the first phase, or they may be asymmetrically disposed. In a preferred embodiment, the die is produced using a specially designed tablet press wherein the surface of the punch which contacts the detergent composition is shaped so that when it contacts and presses the detergent composition, it presses one or more dies into the first phase of the multiphase detergent tablet. Preferably, the die has an inwardly concave or generally concave surface to provide improved adhesion to the second phase. Alternatively, the die may be produced by compressing a preformed body of detergent composition arranged annularly around a central die, thereby forming a shaped body having a die in the form of a cavity extending axially between opposing surfaces of the body.

The tablets of the invention also include one or more additional phases prepared from a composition or compositions comprising one or more detergent components as described below. At least one phase (referred to herein as the second phase) is preferably in the form of a particulate solid (which term includes powders, granules, agglomerates and other particulate solids including mixtures thereof with liquid binders, meltable solids, spray-on materials etc.) compressed within the one or more cavities of the first phase of the detergent tablet so that the second phase itself takes the form of a shaped body. Optional further phases include one or more compositions in the form of a separate layer or layers. Preferred detergent components include builders, colorants, binders, surfactants, disintegrants and enzymes, particularly amylase and protease enzymes. According to another preferred aspect of the present invention, the second and optional further phases comprise a bursting agent which may be selected from either a disintegrating agent or an effervescent agent. Suitable disintegrating agents include agents which swell on contact with water or facilitate the inflow and/or outflow of water by forming channels in the detergent tablet. Any known disintegrating or effervescent agent suitable for use in laundry or dishwashing applications is contemplated for use herein. Suitable demixing agents include starches (such as natural, modified and pregelatinised starches, for example those derived from corn, rice and potato starch), starch derivatives such as U-Sperse (trade name), Primojel (trade name) and Explotab (trade name), celluloses, microcrystalline celluloses and cellulose derivatives such as Arbocel (trade name) and Vivapur (trade name), both available from Rettenmaier, Nymcel (trade name), available from Metsa-serla, Avicel (trade name), Lattice NT (trade name) and Hanfloc (trade name), alginates, acetate trihydrate, burkeite, monohydrated Carbonate of the formula Na₂CO₃·H₂O, hydrated STPP having a Phase I content of at least about 40%, carboxymethylcellulose (CMC), CMC-based polymers, sodium acetate, alumina. Suitable effervescent agents are those which generate a gas upon contact with water. Suitable effervescent agents may be oxygen, nitrogen dioxide or carbon dioxide evolving species. Examples of preferred effervescent agents may be selected from the group consisting of perborate, percarbonate, carbonate, bicarbonate in combination with carboxylic or other acids such as citric, sulphamic, malic or maleic acid.

The components of the cleaning composition are mixed together, for example by mixing dry components and adding or spraying liquid components. The components of the second and optionally subsequent phases are then introduced into the cavity provided by the first phase and retained therein.

The preferred embodiment of the present invention comprises two phases; a first and a second phase. The first phase normally comprises a single cavity and the second phase normally consists of a single detergent active composition. However, it is contemplated that the first phase may comprise more than one cavity and the second phase may be made from more than one detergent active composition. Furthermore, it is also contemplated that the second phase may comprise more than one detergent active composition contained within a cavity. It is also contemplated that different detergent active compositions may be contained in separate cavity forms. In this way, potentially chemically sensitive detergent components may be separated to avoid any loss of performance caused by components reacting with one another and possibly becoming inactive or depleted.

In the present invention, the first, second and/or optionally subsequent phases may comprise a binder. It is necessary that the second phase contains a binder. The binder is selected from the group consisting of organic polymers, for example polyethylene and/or polypropylene glycols, particularly those with a molecular weight of 4,000, 6,000 and 9,000, paraffins, polyvinylpyrolidone (PVP), particularly PVP with a molecular weight of 90,000, polyacrylates, sugars and sugar derivatives, starch and starch derivatives, for example hydroxypropylmethylcellulose (HPMC) and carboxymethylcellulose (CMC); and inorganic polymers such as hexametaphosphate. The binder is valuable both for tablet integrity and for helping to achieve differential dissolution of the first and second phases as described below.

According to a preferred aspect of the present invention, the first phase weighs more than 3 g, preferably more than 4 g, more preferably more than 5 g. More preferably, the first phase weighs 10 g to 30 g, even more preferably 15 g to 25 g, and most preferably 18 g to 24 g. The second and optionally subsequent phases weigh less than 4 g. More preferably, the second and/or optionally subsequent phases weigh between 0.1 g and 3.5 g, preferably between 1 g and 3.5 g, most preferably 1.3 g to 2.5 g.

In another embodiment of the present invention, a barrier layer comprising a barrier layer composition is disposed between the first and second phases and/or optionally subsequent phases, or indeed between the second and optionally subsequent phases. The barrier layer composition comprises at least one binder selected from the group described above. The advantage of the presence of a barrier layer is to prevent or reduce the migration of components from one phase to another phase, for example from the first phase to the second phase and/or optionally subsequent phases and vice versa.

The components of the second and optionally subsequent phases are preferably compressed at a very low compression force relative to a compression force normally used to make tablets. An advantage of the present invention is thus that, since a low compression force is used, heat, force or chemically sensitive detergent components can be incorporated into the detergent tablet without suffering the consequent loss of performance which usually occurs when such components are incorporated into tablets. Alternatively, the second phase or phases can be compressed at the same or higher compression force than the first phase to achieve differential dissolution of the phases as described below.

A further advantage of the present invention is the improved protection of the second phase against damage caused, for example, by handling and transportation. As described above, multiphase detergent tablets have been prepared wherein the second layer has been compressed at a lower compression force than the first layer. However, although the dissolution rate is improved, the second layer of these tablets becomes vulnerable to damage, with a tendency to crumble or disintegrate upon contact. However, the slightly compressed phase(s) of the detergent tablets of the invention are protected within the cavity provided by the first phase of the detergent tablet.

Yet another advantage of the present invention is the ability to produce a multiphase detergent tablet wherein one phase can be designed to dissolve, preferably significantly, before another phase. In the present invention, it is preferred that the second and optionally subsequent phase(s) dissolve before the first phase. According to the preferred weight ratios as described above, it is preferred that the first phase dissolves in 5 to 20 minutes, more preferably 10 to 15 minutes, and the second and/or optionally subsequent phases dissolve in less than 5 minutes, more preferably less than 4.5 minutes, most preferably less than 4 minutes. Alternatively, the second phase may dissolve after the first or other phases, for example where it is desired to provide cleaning or rinsing benefits towards the end of the wash cycle. The times at which the first, second and/or optionally subsequent phases dissolve are independent of each other. According to the present invention, differential dissolution of the phases is thus achieved. A particular advantage of being able to achieve differential dissolution of the multi-phase detergent tablet is that a component which is chemically inactivated by the presence of another component can be separated into a different phase. In this case, the component which is inactivated is preferably located in the second and/or optionally subsequent phase(s).

Yet another advantage of the present invention is the improved adhesion between the phases of the multiphase tablet. It is believed that the improved adhesion is achieved by reducing the exposure of the second phase compared to prior art multiphase tablets, resulting in the tablets of the present invention being less susceptible to breakage along the line of contact between the phases.

Proceedings

The multiphase detergent tablets are prepared using any suitable tabletting equipment, for example a Courtoy R253. Preferably, the tablets are prepared by compression in a tablet press capable of producing a tablet comprising a hollow form. In a particularly preferred embodiment of the present invention, the first phase is prepared using a specially designed tablet press following the procedure described below. The Punches of these tablet presses are modified so that the surface of the punch which contacts the detergent composition has a convex surface.

A first detergent composition is introduced into the die of the tablet press and the punch is lowered to contact and then compress the detergent composition to form a first phase. The first detergent composition is compressed using an applied pressure generally of at least 24.5 MPa (250 kg/cm²), preferably between 34.3 (350) and 196 MPa (2,000 kg/cm²), more preferably 49 (500) to 147 MPa (1,500 kg/cm²), most preferably 58.8 (600) to 117.6 MPa (1,200 kg/cm²). The punch is then raised exposing the first phase containing a cavity. A second and/or optionally subsequent detergent composition(s) is then introduced into the cavity. The specially designed tabletting punch is then lowered a second time to slightly compress the second and/or optionally subsequent detergent composition(s) to form the second and/or optionally subsequent phase(s). In another embodiment of the present invention, wherein an optional subsequent phase is present, the optional subsequent phase is prepared in an optionally subsequent compression stage substantially equivalent to the second compression stage described above. The second and/or optionally subsequent detergent composition(s) is compressed at a pressure of preferably less than 34.3 MPa (350 kg/cm²), more preferably 3.92 (40) to 29.4 MPa (300 kg/cm²), most preferably 5.88 (60) to 26.5 MPa (270 kg/cm²). After compression of the second detergent composition, the plunger is raised a second time and the multiphase detergent tablet is ejected from the tablet press.

Cleaning agent components

The first and second and/or optionally subsequent phases of the multiphase detergent tablet described herein are prepared by compressing one or more compositions comprising detergent active components. Suitably, the compositions used in each of these phases may contain a variety of different detergent components including builder compounds, surfactants, enzymes, bleaches, alkalinity sources, colorants, perfume, lime soap dispersants, organic polymeric compounds including polymeric dye transfer inhibiting agents, crystal growth inhibitors, heavy metal ion complexing agents, metal ion salts, enzyme stabilizers, corrosion inhibitors, foam suppressors, solvents, fabric softeners, optical brighteners and hydrotropes or solubilizers.

Highly preferred first phase detergent components include a builder compound, a surfactant, an enzyme and a bleach. Highly preferred second phase detergent components include builders, enzymes, crystal growth inhibitors and disintegrants and/or binders.

Builder connection

The tablets according to the invention preferably contain a builder compound, typically in a proportion of 1 to 80% by weight, preferably 10 to 70% by weight, most preferably 20 to 60% by weight, of the composition of the detergent active components.

Water soluble builder compound

Suitable water-soluble builder compounds include the water-soluble monomeric polycarboxylates or their acid forms, homo- or copolymeric polycarboxylic acids or salts thereof, wherein the polycarboxylic acid comprises at least two carboxyl radicals separated from each other by not more than two carbon atoms, carbonates, bicarbonates, borates, phosphates and mixtures of any of the foregoing.

The carboxylate or polycarboxylate builder may be of the monomeric or oligomeric type, although monomeric polycarboxylates are generally preferred for reasons of cost and performance.

Suitable carboxylates containing one carboxy group include the water-soluble salts of lactic acid, glycolic acid and their ether derivatives. Polycarboxylates containing two carboxy groups include the water-soluble salts of succinic acid, malonic acid, (ethylenedioxy)diacetic acid, maleic acid, diglycolic acid, tartaric acid, tartronic acid and fumaric acid as well as the ether carboxylates and the sulfinyl carboxylates. Polycarboxylates containing three carboxy groups include, in particular, water-soluble citrates, aconitrates and citraconates, as well as succinate derivatives such as the carboxymethyloxysuccinates described in British Patent No. 1,379,241, the lactoxysuccinates described in British Patent No. 1,389,732 and the aminosuccinates described in Dutch Application 7205873, and the oxypolycarboxylate materials such as 2-oxa-1,1,3-propanetricarboxylates described in British Patent No. 1,387,447.

Polycarboxylates containing four carboxy groups include the oxydisuccinates, 1,1,2,2-ethanetetracarboxylates, 1,1,3,3-propanetetracarboxylates and 1,1,2,3-propanetetracarboxylates described in British Patent No. 1,261,829. Polycarboxylates containing sulfo substituents include the sulfosuccinate derivatives described in British Patent Nos. 1,398,421 and 1,398,422 and in U.S. Patent No. 3,936,448, and the sulfonated, pyrolyzed citrates described in British Patent No. 1,439,000.

Alicyclic and heterocyclic polycarboxylates comprising cyclopentane-cis,cis,cis-tetracarboxylates, cyclopentadienidepentacarboxylates, 2,3,4,5-tetrahydrofuran-cis,cis,cis-tetracarboxylate, 2,5-tetrahydrofuran-cis-dicarboxylate, 2,2,5,5-tetrahydrofuran-tetracarboxylate, 1,2,3,4,5,6-hexane-hexacarboxylate and carboxymethyl derivatives of polyhydric alcohols such as sorbitol, mannitol and xylitol. Aromatic polycarboxylates include mellitic acid, pyromellitic acid and phthalic acid derivatives such as those described in British Patent No. 1,425,343.

Among the above, the preferred polycarboxylates are hydroxycarboxylates containing up to three carboxy groups per molecule, particularly citrates.

The parent acids of the monomeric or oligomeric polycarboxylate complexing agents or mixtures thereof with their salts, for example citric acid or citrate/citric acid mixtures, are also included as useful builder components.

Borate builders and builders containing borate-forming materials that can generate borate under detergent storage or wash conditions may also be used, but are not preferred under wash conditions of less than 50ºC, especially less than 40ºC.

Examples of carbonate builders are the alkaline earth and alkali metal carbonates, including sodium carbonate and sesquicarbonate and mixtures thereof with ultrafine calcium carbonate, as described in German Patent Application No. 2,321,001, published November 15, 1973.

Highly preferred builder compounds for use in the present invention are water-soluble phosphate builders. Specific examples of water-soluble phosphate builders are the alkali metal tripolyphosphates, sodium, potassium and ammonium pyrophosphates, sodium and potassium orthophosphates, sodium polymeta/phosphate wherein the degree of polymerization is in the range of 6 to 21, and salts of phytic acid.

Partially soluble or insoluble builder compound

The tablets according to the invention can contain a partially soluble or insoluble builder compound. Partially soluble and insoluble builder compounds are particularly suitable for use in tablets which have been manufactured for use in laundry cleaning processes. Examples of partially water-soluble builders include the crystalline layered silicates as described, for example, in EP-A-0 164 514, DE-A-34 17 649 and DE-A-37 42 043. Preference is given to the crystalline sodium layered silicates of the general formula

NaMSixO2+1 ·yH2O

where M is sodium or hydrogen, x is a number from 1.9 to 4, and y is a number from 0 to 20. Crystalline sodium layered silicates of this type preferably have a two-dimensional "sheet" structure, such as the so-called δ-layer structure as described in EP 0 164 514 and EP 0 293 640. Processes for the preparation of crystalline layered silicates of this type are disclosed in DE-A-34 17 649 and DE-A-37 42 043. For the purposes of the invention, x in the above general formula has a value of 2, 3 or 4, and is preferably 2.

The most preferred crystalline sodium layered silicate compound has the formula δ-Na₂Si₂O₅, known as NaSKS-6 (trade name), as available from Hoechst AG.

The crystalline layered sodium silicate material is preferably present in granular detergent compositions as particles in intimate admixture with a solid, water-soluble, ionizable material as described in PCT Patent Application No. WO 92/18594. The solid, water-soluble, ionizable material is selected from organic acids, organic and inorganic acid salts, and mixtures thereof, with citric acid being preferred.

Examples of largely water-insoluble builders include the sodium aluminosilicates. Suitable aluminosilicates include the aluminosilicate zeolites having the unit cell formula Naz[(AlO₂)z(SiO₂)y].xH₂O, where z and y are at least 6; the molar ratio of z to y is 1.0 to 0.5, and x is at least 5, preferably 7.5 to 276, more preferably 10 to 264. The aluminosilicate materials are in hydrated form and are preferably crystalline, containing 10 to 28%, more preferably 18 to 22%, water in bound form.

The aluminosilicate zeolites can be naturally occurring materials, but are preferably synthetically derived. Synthetic crystalline aluminosilicate ion exchange materials are available under the names Zeolite A, Zeolite B, Zeolite P, Zeolite X, Zeolite HS and mixtures thereof.

A preferred method for preparing aluminosilicate zeolites is that described by Schoeman et al. (published in Zeolite (1994) 14 (2), 110-116) in which the author describes a process for preparing colloidal aluminosilicate zeolites. The colloidal aluminosilicate zeolite particles should preferably be such that no more than 5% of the particles have a size of more than 1 µm in diameter and no more than 5% of the particles have a size of less than 0.05 µm in diameter. Preferably the aluminosilicate zeolite particles have an average particle size diameter of between 0.01 µm and 1 µm, more preferably between 0.05 µm and 0.9 µm, most preferably 0.1 µm and 0.6 µm.

Zeolite A has the formula

Na 12 (AlO 2 ) 12 (SiO 2 ) 12 ]·xH 2 O

wherein x is 20 to 30, especially 27. Zeolite X has the formula Na₈₆[(AlO₂)₈₆(SiO₂)₁₀₆]·276H₂O. Zeolite MAP as described in EP-B-348,070 is a preferred zeolite builder herein.

Preferred aluminosilicate zeolites are the colloidal aluminosilicate zeolites. When used as a component of a detergent composition, colloidal aluminosilicate zeolites, particularly colloidal zeolite A, provide enhanced builder performance in providing improved stain removal. Enhanced builder performance is also demonstrated in reducing fabric scaling and improving fabric whiteness retention, problems believed to be associated with weakly built detergent compositions.

A surprising finding is that mixed aluminosilicate-zeolite detergent compositions comprising colloidal zeolite A and colloidal zeolite Y provide equal calcium ion complexing performance over an equal weight of commercially available zeolite A. Another surprising finding is that mixed aluminosilicate-zeolite detergent compositions as described above exhibit improved magnesium ion complexing performance over an equal weight of commercially available zeolite A.

Surfactant

Surfactants are preferred detergent active components of the compositions described herein. Suitable surfactants are selected from anionic, cationic, nonionic, ampholytic and zwitterionic surfactants and mixtures thereof. Machine dishwashing products should be low foaming in character, so that the foaming of the surfactant system for use in dishwashing methods must be suppressed, or more preferably low foaming, typically nonionic in character. Foaming caused by surfactant systems used in laundry cleaning methods need not be suppressed to the same extent as is necessary for dishwashing. The surfactant is typically present in a proportion of 0.2 to 30% by weight, further preferably 0.5 to 10 wt.%, most preferably 1 to 5 wt.%, of the composition of the detergent active components.

A typical listing of anionic, nonionic, ampholytic and zwitterionic classes and species of these surfactants is given in U.S. Patent No. 3,929,678, issued December 30, 1975 to Laughlin and Heuring. A list of suitable cationic surfactants is given in U.S. Patent No. 4,259,217, issued March 31, 1981 to Murphy. A listing of surfactants typically included in automatic dishwashing detergent compositions is given, for example, in EP-A-0 414 549 and PCT Application Nos. WO 93/08876 and WO 93/08874.

Non-ionic surfactant

Essentially any non-ionic surfactants useful for detergent purposes may be included in the detergent tablet. Preferred, non-limiting classes of suitable non-ionic surfactants are listed below.

Non-ionic ethoxylated alcohol surfactant

The alkyl ethoxylate condensation products of aliphatic alcohols with 1 to 25 moles of ethylene oxide are suitable for use herein. The alkyl chain of the aliphatic alcohol can be either straight or branched chain, primary or secondary, and generally contains 6 to 22 carbon atoms. Particularly preferred are the condensation products of alcohols having an alkyl group containing 8 to 20 carbon atoms with 2 to 10 moles of ethylene oxide per mole of alcohol.

Endcapped alkyl alkoxylate surfactant

Suitable end-capped alkyl alkoxylate surfactants are the epoxy-capped poly(oxyalkylated) alcohols of the formula:

R1 O[CH2 CH(CH3 )O]x[CH2 CH2 O]y[CH2 CH(OH)R2 ] (I)

wherein R₁ is a linear or branched aliphatic hydrocarbon radical having 4 to 18 carbon atoms; R₂ is a linear or branched aliphatic hydrocarbon radical having 2 to 26 carbon atoms; x is an integer having an average value of 0.5 to 1.5, more preferably 1; and y is an integer having a value of at least 15, more preferably at least 20.

Preferably, the surfactant of formula I contains at least 10 carbon atoms in the terminal epoxide unit [CH₂CH(OH)R₂]. Suitable surfactants of formula I within the meaning of the present invention are the nonionic POLY-TERGENT®SLF-18B surfactants from Olin Corporation, as described, for example, in WO 94/22800, published October 13, 1994, by Olin Corporation.

Ether-capped poly(oxyalkylated) alcohols

Preferred surfactants for use herein include ether-capped poly(oxyalkylated) alcohols of the formula:

R¹O(CH₂CH(R³)O]x[CH₂]kCH(OH)[CH₂]jOR²

wherein R¹ and R² are linear or branched saturated or unsaturated, aliphatic or aromatic hydrocarbon radicals having 1 to 30 carbon atoms; R³ is H or a linear aliphatic hydrocarbon radical having 1 to 4 carbon atoms; x is an integer having an average value of 1 to 30, wherein when x is 2 or greater, R³ may be the same or different, and k and j are integers having an average value of 1 to 12, and more preferably 1 to 5.

R¹ and R² are preferably linear or branched, saturated or unsaturated, aliphatic or aromatic hydrocarbon radicals with 6 to 22 carbon atoms, with 8 to 18 carbon atoms being most preferred. H or a linear aliphatic hydrocarbon radical having 1 to 2 carbon atoms is most preferred for R³: Preferably, x is an integer having an average value of 1 to 20, more preferably 6 to 15.

As described above, in the preferred embodiments, when x is greater than 2, R³ may be the same or different. That is, R³ may vary between any of the alkyleneoxy units described above. For example, when x is 3, R³ may be selected from ethyleneoxy (EO) or propyleneoxy (PO) and may vary in the order of (EO) (PO) (EO); (EO) (EO) (PO); (EO) (EO) (EO); (PO) (EO) (PO); (PO) (PO) (PO) (EO) and (PO) (PO) (PO) (PO). The integer three is of course chosen only as an example, and the variation may be substantially greater with a higher integer value for x and may include, for example, multiple (EO) units and a very small number of (PO) units.

Particularly preferred surfactants as described above include those which have a low cloud point of less than 20°C. These low cloud point surfactants can then be used in conjunction with a high cloud point surfactant as described in detail below for excellent grease cleaning benefits.

Most preferred ether-capped poly(oxyalkylated) alcohol surfactants are those where k is 1 and j is 1, such that the surfactants have the formula :

R¹O[CH₂CH(R³)O]xCH₂CH(OH)CH₂OR²

wherein R¹, R² and R³ are as defined above, and x is an integer having an average value of 1 to 30, preferably 1 to 20, and even more preferably 6 to 18. Most preferred are surfactants wherein R¹ and R² are in the range of 9 to 14, R³ is H to form ethyleneoxy and x is in the range 6 to 15.

The ether-capped poly(oxyalkylated) alcohol surfactants comprise three general components, namely a linear or branched alcohol, an alkylene oxide and an alkyl ether end cap. The alkyl ether end cap and alcohol serve as the hydrophobic, oil-soluble part of the molecule, while the alkylene oxide group forms the hydrophilic, water-soluble part of the molecule.

These surfactants show significant improvements in spotting and film forming characteristics and greasy soil removal when used in conjunction with high cloud point surfactants relative to conventional surfactants.

Generally speaking, the ether-capped poly(oxyalkylene) alcohol surfactants of the present invention can be prepared by reacting an aliphatic alcohol with an epoxide to form an ether, which is then reacted with a base to form a second epoxide. The second epoxide is then reacted with an alkoxylated alcohol to form the novel compounds of the invention. Examples of processes for preparing the ether-capped poly(oxyalkylene) alcohol surfactants are described below:

Production of C12/14 alkyl glycidyl ethers

A C12/14 fatty alcohol (100.00 g, 0.515 mol) and stannous chloride (0.58 g, 2.23 mmol, available from Aldrich) are combined in a 500 mL three-necked round-bottom flask equipped with a condenser, argon inlet, addition funnel, magnetic stirrer, and internal temperature probe. The mixture is heated to 60ºC. Epichlorohydrin (47.70 g, 0.515 mol, available from Aldrich) is added dropwise so that the temperature is maintained between 60-65ºC. After stirring for an additional hour at 60ºC, the mixture is cooled to room temperature. The mixture is washed with a 50% solution of sodium hydroxide (61.80 g, 2.23 mmol, available from Aldrich).

0.773 mol, 50%) with mechanical stirring. After the addition is complete, the mixture is heated to 90°C for 1.5 hours, cooled and filtered with ethanol. The filtrate is separated and the organic phase is washed with water (100 mL), dried over MgSO4, filtered and concentrated. Distillation of the oil at 100-120°C (13.33 Pa [0.1 mm Hg]) gives the glycidyl ether as an oil.

Preparation of C12/14 alkyl C9/11 ether-capped alcohol surfactant

Neodol® 91-8 (20.60 g, 0.0393 mol, ethoxylated alcohol available from Shell Chemical Co.) and stannous chloride (0.58 g, 2.23 mmol) are combined in a 250 mL three-necked round-bottom flask equipped with a condenser, argon inlet, addition funnel, magnetic stirrer, and internal temperature probe. The mixture is heated to 60ºC at which point C12/14 alkyl glycidyl ether (11.00 g, 0.0393 mol) is added dropwise over 15 minutes. After stirring for 18 hours at 60ºC, the mixture is cooled to room temperature and dissolved in an equal portion of dichloromethane. The solution is passed over a 1-inch pad of silica gel while eluting with dichloromethane. The filtrate is concentrated by rotary evaporation and then stripped in a Kugelrohr oven (100ºC, 66.66 Pa [0.5 mm Hg]) to yield the surfactant as an oil.

Non-ionic ethoxylated/propoxylated fatty alcohol surfactant

The ethoxylated C6-C18 fatty alcohols and mixed ethoxylated/propoxylated C6-C18 fatty alcohols are suitable surfactants for use herein, particularly if they are water soluble. Preferably, the ethoxylated fatty alcohols are the ethoxylated C₁₀-C₁₈ fatty alcohols with a degree of ethoxylation of 3 to 50, most preferably these are the ethoxylated C₁₂-C₁₈ fatty alcohols with a degree of ethoxylation of 3 to 40. Preferably, the mixed ethoxylated/propoxylated fatty alcohols have an alkyl chain length of 10 to 18 carbon atoms, a degree of ethoxylation of 3 to 30 and a degree of propoxylation of 1 to 10.

Non-ionic EO/PO condensates with propylene glycol

The condensation products of ethylene oxide with a hydrophobic base, formed by the condensation of propylene oxide with propylene glycol, are suitable for use herein. The hydrophobic portion of these compounds preferably has a molecular weight of from 1500 to 1800 and exhibits water insolubility. Examples of compounds of this type, include certain of the commercially available PluronicTM surfactants, sold by BASF.

Non-ionic EO condensation products with propylene oxide/ethylenediamine adducts

The condensation products of ethylene oxide with the product resulting from the reaction of propylene oxide and ethylenediamine are suitable for use herein. The hydrophobic portion of these products consists of the reaction product of ethylenediamine and excess propylene oxide and generally has a molecular weight of 2500 to 3000. Examples of this type of nonionic surfactant include certain of the commercially available TetronicTM compounds sold by BASF.

Mixed non-ionic surfactant system

In a preferred embodiment of the present invention, the detergent tablet comprises a mixed nonionic surfactant system comprising at least one low cloud point nonionic surfactant and at least one high cloud point nonionic surfactant.

"Cloud point" as used herein is a well-known property of nonionic surfactants which is the result of the surfactant becomes less soluble with increasing temperature, the temperature at which the appearance of a second phase becomes observable being called the "cloud point" (see Kirk Othmer's Encyclopedia of Chemical Technology, 3rd edition, Volume 22, pages 360-379).

As used herein, a nonionic surfactant having a "low cloud point" is defined as a component of a nonionic surfactant system having a cloud point of less than 30°C, preferably less than 20°C, and most preferably less than 10°C. Typical low cloud point nonionic surfactants include nonionic alkoxylated surfactants, particularly ethoxylates derived from primary alcohol and polyoxypropylene/polyoxyethylene/polyoxypropylene (PO/EO/PO) reverse block polymers. Also, such low cloud point nonionic surfactants include, for example, ethoxylated-propoxylated alcohol (e.g., Poly-Tergent® SLF 18 from Olin Corporation), epoxy-capped poly(oxyalkylated) alcohols (e.g., Poly-Tergent® SLF 18B series of nonionic surfactants from Olin Corporation, as described, for example, in WO 94/22800, published October 13, 1994, from Olin Corporation), and the ether-capped poly(oxyalkylated) alcohol surfactants.

Nonionic surfactants may optionally contain propylene oxide in an amount of up to 15% by weight. Other preferred nonionic surfactants can be prepared by the processes described in U.S. Patent 4,223,163, issued September 16, 1980 to Builloty.

Low cloud point nonionic surfactants additionally comprise a polymeric compound having a polyoxyethylene, polyoxypropylene block. Polymeric polyoxyethylene-polyoxypropylene block compounds include those based on ethylene glycol, propylene glycol, glycerol, trimethylolpropane and ethylenediamine as the initiator reactive hydrogen compound. Certain of the block polymer surfactant compounds, referred to as PLURONIC®, REVERSED PLURONIC® and TETRONIC® from BASF-Wyandotte Corp., Wyandotte, Michigan, are used in ADD compositions of the invention. Preferred examples include REVERSED PLURONIC® 25R2 and TETRONIC® 702. Such surfactants are typically useful herein as low cloud point nonionic surfactants.

As used herein, a "high cloud point" nonionic surfactant is defined as a component of a nonionic surfactant system having a cloud point of greater than 40°C, preferably greater than 50°C, and more preferably greater than 60°C. Preferably, the nonionic surfactant system comprises an ethoxylated surfactant derived from the reaction of a monohydroxy alcohol or alkylphenol containing 8 to 20 carbon atoms with an average of 6 to 15 moles of ethylene oxide per mole of alcohol or alkylphenol. Such high cloud point nonionic surfactants include, for example, Tergitol 15S9 (available from Union Carbide), Rhodasurf TMD 8.5 (available from Rhone Poulenc) and Neodol 91-8 (available from Shell).

For the purposes of the invention, it is also preferred that the high cloud point nonionic surfactant further has a hydrophilic-lipophilic ratio ("HLB"; see Kirk Othmer, cited above) within the range of 9 to 15, preferably 11 to 15. Such materials include, for example, Tergitol 1559 (available from Union Carbide), Rhodasurf TMD 8.5 (available from Rhone Poulenc) and Neodol 91-8 (available from Shell).

Another preferred high cloud point nonionic surfactant is derived from a straight or preferably branched chain or secondary fatty alcohol having 6 to 20 carbon atoms (C6-C20 alcohol), including secondary alcohols and branched chain primary alcohols. Preferably, high cloud point nonionic surfactants are branched or secondary alcohol ethoxylates, more preferably mixed branched C9/11 or C11/15 alcohol ethoxylates, condensed with an average of 6 to 15 moles, preferably 6 to 12 moles, most preferably 6 to 9 moles, of ethylene oxide per mole of alcohol.

Preferably, an ethoxylated nonionic surfactant derived in this way has a narrow ethoxylate distribution compared to the average.

Anionic surfactant

Essentially any anionic surfactant useful for detersive purposes is suitable. These may include salts (including, for example, sodium, potassium, ammonium and substituted ammonium salts such as mono-, di- and triethanolamine salts) of the anionic sulfate, sulfonate, carboxylate and sarcosinate surfactants. Anionic sulfate surfactants are preferred.

Other anionic surfactants include isethionates, such as acylisethionates, N-acyl taurates, fatty acid amides of methyl tauride, alkyl succinates and sulfosuccinates, monoesters of sulfosuccinate (in particular saturated and unsaturated C₁₂-C₁₈ monoesters)-diesters of sulfosuccinate (in particular saturated and unsaturated C₆-C₁₄ diesters), N-acyl sarcosinates. Resin acids and hydrogenated resin acids are also suitable, as are rosin, hydrogenated rosin and resin acids and hydrogenated resin acids which are present in tallow oil or are derived therefrom.

Anionic sulfate surfactant

Anionic sulfate surfactants suitable for use herein include the linear and branched, primary and secondary alkyl sulfates, alkyl ethoxy sulfates, fatty oleyl glycerol sulfates, alkylphenol ethylene oxide ether sulfates, the C5-C17 acyl-N-(C1-C4 alkyl) and N-(C1-C2 hydroxyalkyl) glucamine sulfates, and sulfates of alkyl polysaccharides such as the sulfates of alkyl polyglucoside (the nonionic non-sulfated compounds are described herein).

Alkyl sulfate surfactants are preferably selected from the linear and branched primary C₁₀-C₁₈ alkyl sulfates, more preferably the branched chain C₁₁₁₅-C₁₅ alkyl sulfates and the linear chain C₁₂-C₁₄ alkyl sulfates.

Alkyl ethoxysulfate surfactants are preferably selected from the group consisting of the C10-C18 alkyl sulfates which have been ethoxylated with 0.5 to 20 moles of ethylene oxide per molecule. More preferably, the alkyl ethoxysulfate surfactant is a C11-C18, most preferably C11-C15 alkyl sulfate which has been ethoxylated with 0.5 to 7, preferably 1 to 5, moles of ethylene oxide per molecule.

According to a particularly preferred aspect of the invention, mixtures of the preferred alkyl sulfate and alkyl ethoxy sulfate surfactants are employed. Such mixtures have been described in PCT Patent Application No. WO 93/18124.

Anionic sulfonate surfactant

Anionic sulfonic surfactants suitable for use herein include the salts of C5-C20 linear alkylbenzenesulfonates, alkyl ester sulfonates, C6-C22 primary or secondary alkanesulfonates, C6-C24 olefin sulfonates, sulfonated polycarboxylic acids, alkylglycerol sulfonates, fatty acylglycerol sulfonates, fatty oleylglycerol sulfonates, and any mixtures thereof.

Anionic carboxyl surfactant

Suitable anionic carboxyl surfactants include the alkyl ethoxycarboxylates, the alkyl polyethoxypolycarboxylate surfactants and the soaps (“alkyl carboxyls”), particularly certain secondary soaps, as described herein.

Suitable alkyl ethoxycarboxylates include those having the formula RO(CH₂CH₂O)xCH₂COO⁻M⁺, wherein R is a C₆-C₁₈ alkyl group, x ranges from 0 to 10, and the ethoxylate distribution, on a weight basis, is such that the amount of material wherein x is 0 is less than 20%, and M is a cation. Suitable alkyl polyethoxy polycarboxylate surfactants include those of the formula RO-(CHR₁-CHR₂-O)-R₃, wherein R is a C₆-C₁₈ alkyl group, x is 1 to 25, R₁ and R₂ are selected from the group consisting of hydrogen, methyl acid radical, succinic acid radical, hydroxysuccinic acid radical, and mixtures thereof, and R₃ is selected from the group consisting of hydrogen, substituted or unsubstituted hydrocarbon having 1 to 8 carbon atoms, and mixtures thereof.

Suitable soap surfactants include the secondary soap surfactants which contain a carboxyl moiety linked to a secondary carbon. Preferred secondary soap surfactants for use herein are water-soluble members selected from the group consisting of water-soluble salts of 2-methyl-1-undecanoic acid, 2-ethyl-1-decanoic acid, 2-propyl-1-nonanoic acid, 2-butyl-1-octanoic acid, and 2-pentyl-1-heptanoic acid. Certain soaps may also be included as suds suppressors.

Alkali metal sarcosinate surfactant

Other suitable anionic surfactants are the alkali metal sarcosinates of the formula R-CON (R¹) CH₂COOM, in which R is a linear or branched C₅-C₁₇-alkyl or alkenyl group, R¹ is a C₁-C₄-alkyl group and M is an alkali metal ion. Preferred examples are the myristyl and oleylmethyl sarcosinates in the form of their sodium salts.

Amphoteric surfactant

Suitable amphoteric surfactants for use herein include the amine oxide surfactants and the alkylamphocarboxylic acids.

Suitable amine oxides include the compounds having the formula R³(OR⁴)xN⁴(R⁵)₂ wherein R³ is selected from alkyl, hydroxyalkyl, acylamidopropyl and alkylphenyl groups or mixtures thereof containing 8 to 26 carbon atoms; R⁴ is an alkylene or hydroxyalkylene group having 2 to 3 carbon atoms, or mixtures thereof; x is 0 to 5, preferably 0 to 3; and each R⁵ is an alkyl or hydroxyalkyl group having 1 to 3, or a polyethylene oxide group having 1 to 3 ethylene oxide groups. Preferred are C₁₀-C₁₈ alkyldimethylamine oxide and C₁₀-C₁₈ acylamidoalkyldimethylamine oxide.

A suitable example of an alkylamphodicarboxylic acid is Miranol(TM) C2M Conc., manufactured by Miranol, Inc., Dayton, NJ.

Zwitterionic surfactant

Zwitterionic surfactants may also be incorporated into the detergent compositions herein. These surfactants may be broadly described as derivatives of secondary and tertiary amines, derivatives of heterocyclic secondary and tertiary amines, or derivatives of quaternary ammonium, quaternary phosphonium, or tertiary sulfonium compounds. Betaine and sultaine surfactants are exemplary zwitterionic surfactants for use herein.

Suitable betaines are the compounds having the formula R(R')2N+R2COO- wherein R is a C6-C18 hydrocarbyl group, each R1 is typically C1-C3 alkyl, and R2 is a C1-C5 hydrocarbyl group. Preferred betaines are C12-C18 dimethylammoniohexanoate and the C10-C18 acylamidopropane (or ethane)dimethyl (or diethyl) betaines. Complex betaine surfactants are also suitable for use herein.

Cationic surfactants

Cationic ester surfactants used in the invention are preferably water-dispersible compounds having surfactant properties comprising at least one ester (ie -COO-) bond and at least one cationically charged group. Other suitable cationic ester surfactants, including choline ester surfactants, are described, for example, in US patents Nos. 4,228,042, 4,239,660 and 4,260,529.

Suitable cationic surfactants include the quaternary ammonium surfactants selected from mono-C6-C16, preferably C6-C10 N-alkyl or alkenyl ammonium surfactants, wherein the remaining N-positions are substituted by methyl, hydroxyethyl or hydroxypropyl groups.

Enzymes

Enzymes are preferred cleaning or detergent components of the first phase and in particular of the second and/or optionally the further phases. If present, the enzymes are selected from the group consisting of cellulases, hemicellulases, peroxidases, proteases, glucoamylases, amylases, xylanases, lipases, phospholipases, esterases, cutinases, pectinases, keratanases, reductases, oxidases, phenoloxidases, ligoxygenases, ligninases, puliulanases, tannases, pentosanases, malanases, b-glucanases, arabinosidases, hyaluronidase, chondroitinase, laccase or mixtures thereof.

Preferred enzymes include protease, amylase, lipase, peroxidases, cutinase and/or cellulase in conjunction with one or more plant cell wall degrading enzymes.

The cellulases useful in the present invention include either bacterial or fungal cellulase. Preferably they have a pH optimum between 5 and 12 and an activity above 50 CEVU (Cellulose Viscosity Unit). Suitable cellulases are described in US Patent 4,435,307, Barbesgoard et al. J61078384 and WO 96/02653, which describe fungal cellulases produced from Humicola insolens, Trichoderma, Thielavia and Sporotrichum, respectively. EP 739 982 describes cellulases isolated from new Bacillus species. Suitable cellulases are also described in GB-A-2 075 028; GB-A-2 095 275; DE-OS-22 47 832 and WO 95/26398.

Examples of such cellulases are cellulases produced by a strain of Humicola insolens (Humicola grisea var. thermoidea), in particular Humicola strain DSM 1800. Other suitable cellulases are cellulases derived from Humicola insolens, having a molecular weight of 50 KDa, an isoelectric point of 5.5, and containing 415 amino acids; and a 43kD endoglucanase derived from Humicola insolens, DSM 1800, which exhibits cellulase activity; a preferred endogluconase component has the amino acid sequence described in PCT Patent Application No. WO 91/17243. Also suitable cellulases are the EGIII cellulases from Trichoderma longibrachiatum, described in WO 94/21801, Genencor, published September 29, 1994. Particularly suitable cellulases are the cellulases which have dye care benefits. Examples of such cellulases are the cellulases described in EP-A-495257, filed November 6, 1991 (Novo). Carezyme and Celluzyme (Novo Nordisk A/S) are particularly useful. See also WO 91/17244 and WO 91/21801. Other suitable cellulases for laundry care and/or cleaning properties are described in WO 96/34092, WO 96/17994 and WO 95/24471.

These cellulases are normally incorporated into the detergent composition in proportions of 0.0001% to 2% inactive enzyme based on the weight of the detergent composition.

Peroxidase enzymes are used in combination with oxygen sources, for example percarbonate, perborate, persulfate, hydrogen peroxide, etc. They are used for "solution bleaching", that is, to prevent the transfer of dyes or pigments removed from substrates during washing operations to other substrates in the washing solution. Peroxidase enzymes are known in the art and include, for example, horseradish peroxidase, ligninase and haloperoxidase, such as chloro- and bromoperoxidase. Peroxidase-containing detergent compositions are described, for example, in the international PCT application WO 89/099813, WO 89/09813 and EP-A-540780, filed on November 6, 1991, and WO 97/30143, filed on February 20, 1996. Laccase enzyme is also suitable.

Preferred enhancers are substituted phenthiazine and phenoxasin, 10-phenothiazinepropionic acid (PPT), 10-ethylphenothiazine-4-carboxylic acid (EPC), 10-phenoxazinepropionic acid (POP) and 10-methylphenoxazine (described in WO 94/12621) and substituted syringates (C3-C5 substituted alkyl syringates) and phenols. Sodium percarbonate or perborate are preferred sources of hydrogen peroxide.

These cellulases and/or peroxidases are normally incorporated into the detergent composition in proportions of 0.0001% to 2% of active enzyme based on the weight of the detergent composition.

Other preferred enzymes which may be included in the detergent compositions of the invention include lipases. Suitable lipase enzymes for laundry use include those produced by microorganisms of the Pseudomonas group such as Pseudomonas stutzeri ATCC 19.154 as described in British Patent 1,372,034. Suitable lipases include those which show a positive immunological cross-reaction with the antibody to the lipase produced by the microorganism Pseudomonas fluorescent IAM 1057. This lipase is available from Amano Pharmaceutical Co., Ltd., Nagoya, Japan under the trade name Lipase P "Amano", referred to herein as "Amano-P". Other suitable commercial lipases include Amano-CES, lipases from Chromobacter viscosum, for example Chromobacter viscosum var, lipolyticum NRRLB 3673 from Toyo Jozo Co., Tagata, Japan; Chromobacter viscosum lipases from US Biochemical Corp., USA and Disoynth Co., Netherlands and lipases from Pseudomonas gladioli. Particularly suitable lipases are lipases such as M1 LipaseR and LipomaxR (Gist-Brocades) and LipolaseR and Lipolase UltraR (Novo), which have been found to be very effective when used in combination with the inventive compositions. Also suitable are the lipolytic enzymes as described in EP 258 068, WO 92/05249 and WO 95/22615 by Novo Nordisk and in WO 94/03578, WO 95/35381 and WO 96/00292 by Unilever.

Also suitable are cutinases [EC 3.1.1.50], which can be considered a special type of lipase, namely lipases that do not require surface activation. The addition of cutinases to detergent compositions has been described, for example, in WO-A-88/09367 (Genencor); WO 90/09446 (Plant Genetic System) and WO 94/14963 and WO 94/14964 (Unilever).

The lipases and/or cutinases are normally incorporated into the detergent composition in proportions of 0.0001% to 2% of active enzyme, based on the weight of the detergent composition.

Suitable proteases are the subtilisins obtained from special strains of B. subtilis and B. licheniformis (subtilisin BPN and BPN'). A suitable protease is obtained from a strain of Bacillus with maximum activity over the entire pH range of 8-12, developed and sold as ESPERASE® by Novo Industries A/S of Denmark, hereinafter "Novo". The production of this enzyme and analogous enzymes is described in GB 1,243,784 to Novo. Other suitable proteases include KANNASE®, ALCALASE®, DURAZYM® and SAVINASE® from Novo and MAXATASE®, MAXACAL®, PROPERASE® and MAXAPEM® (protein-engineered Maxacal) from Gist-Brocades. Proteolytic enzymes also include modified bacterial serine proteases such as those described in EP-A-251446, filed April 28, 1987 (particularly pages 17, 24 and 98), hereinafter referred to as "Protease B", and in European Patent Application 199 404, Venegas, published October 29, 1986, which refers to a modified bacterial proteolytic serine enzyme, referred to herein as "Protease A". Suitable is what is referred to herein as "Protease C", which is a variant of a Bacillus alkaline serine protease, wherein Lysine at position 27 has replaced arginine, tyrosine at position 104 has replaced valine, serine at position 123 has replaced aparagine and alanine at position 274 has replaced threonine. Protease C is described in EP 90 915 958.4, corresponding to WO 91/06637, published on May 16, 1991. Genetically modified variants, in particular protease C, are also included herein.

A preferred protease, designated "Protease D", is a carbonyl hydrolase variant having an amino acid sequence not found in nature, which is derived from a precursor carbonyl hydrolase by substituting a plurality of amino acid residues with a different amino acid at a position in the carbonyl hydrolase which is equivalent to position +76, preferably also in combination with one or more amino acid residue positions which are equivalent to those selected from the group consisting of +99,. +101, +103, +104, +107, +123, +27, +105, +109, +126, +128, +135, +156, +166, +195, +197, +204, +206, +210, +216, +217, +218, +222, +260, +265 and/or +274 according to the numbering of Bacillus amyloliquefaciens subtilisin as described in WO 95/10591 and in the patent application of C. Ghosh, et al., "Bleaching Compositions Comprising Protease Enzymes" with US Serial No. 08/322,677, filed October 13, 1994 (US 6066611).

Also suitable for the present invention are the proteases described in the patent applications EP 251 446 and WO 91/06637, the protease BLAP® described in WO 91/02796 and its variants, described in WO 95/23221.

See also a high pH protease from Bacillus sp. NCIMB 40338, described in WO 93/18140 A to Novo. Enzymatic detergents, comprising protease, one or more other enzymes and a reversible protease inhibitor are described in WO 92/03529 A to Novo. If desired, a protease with reduced adsorption and increased hydrolysis is available as described in WO 95/0779 to Procter & Gamble.

A suitable recombinant trypsin-like protease for detergents is described in WO 94/25583 by Novo. Other suitable proteases are described in EP 516 200 by Unilever.

Further preferred protease enzymes include protease enzymes which are a carbonyl hydrolase variant with an amino acid sequence not found in nature, which is obtained by replacing a plurality of amino acid residues of a precursor carbonyl hydrolase with different amino acids, wherein the plurality of amino acid residues replaced in the precursor enzyme correspond to position +210, in combination with one or more of the following residues: +33, +62, +67, +76, +100, +101, +103, +104, +107, +128, +129, +130, ±132, +135, +156, +158, +164, +166, +167, +170, +209, +215, +217, +218 and +222, wherein the numbered positions correspond to the naturally occurring subtilisin from Bacillus amyloliquefaciens or to equivalent amino acid residues in other carbonyl hydrolases or subtilisins (such as Bacillus lentus subtilisin). Preferred enzymes of this type include those with positional changes +210, +76, +103, +104, +156 and +166.

The proteolytic enzymes are incorporated into the detergent compositions according to the invention in a proportion of 0.0001% to 2%, preferably 0.001% to 0.2%, more preferably 0.005% to 0.1% pure enzyme, based on the weight of the composition.

Amylases (α and/or β) may be included to remove carbohydrate-based stains. WO 94/02597, Novo Nordisk A/S. published February 3, 1994, describes detergent compositions containing mutant amylases. See also WO 95/10603, Novo Nordisk A/S. published April 20, 1995. Other amylases known for use in detergent compositions include both α- and β-amylases. α-Amylases are known in the art and include those described in US Patent No. 5,003,257; EP 252 666; WO 91/00353; FR 2,676,456; EP 285 123; EP 525 610; EP 368 341; and British Patent Specification No. 1,296,839 (Novo). Further suitable amylases are stability-enhanced amylases as described in WO 94/18314, published August 18, 1994, and WO 96/05295, Genencor, published February 22, 1996, and amylase variants with additional modification of the immediate parent available from Novo Nordisk A/S. described in WO 95/10603, published April 95. Also suitable are the amylases described in EP 277 216, WO 95/26397 and WO 96/23873 (all from Novo Nordisk).

Examples of commercial α-amylase products are Purafect Ox Am® from Genencor and Termamyl®, Ban®, Fungamyl® and Duramyl®, Natalase®, all available from Novo NordiskA/S Denmark. WO 95/26397 describes other suitable amylases: α-amylases which are characterized by a specific activity that is at least 25% higher than the specific activity of Thermamyl® at a temperature range of 25ºC to 55ºC and at a pH in the range of 8 to 10, measured by the Phadebas® α-amylase activity assay. Suitable are variants of the above enzymes described in WO 96/23873 (Novo Nordisk). Further amylolytic enzymes with improved properties in terms of the level of activity and the combination of thermostability and a higher level of activity are described in WO 95/35382.

Preferred amylase enzymes include those described in WO 95/26397 and Novo Nordisk's co-pending application WO 96/23873.

The amylolytic enzymes are incorporated into the detergent compositions of the invention in a proportion of 0.0001% to 2%, preferably 0.00018% to 0.06%, more preferably 0.00024% to 0.048%, pure enzyme, based on the weight of the composition.

In a particularly preferred embodiment, cleaning tablets according to the invention comprise amylase enzymes, in particular those described in WO 95/26397 and the co-pending application WO 96/23873 by Novo Nordisk, in combination with a complementary amylase.

By "complementary" is meant the addition of one or more amylases suitable for washing or cleaning purposes. Examples of complementary amylases (α and/or β) are described below. WO 94/02597 and WO 95/10603, Novo Nordisk A/S. describe cleaning compositions containing mutant amylases. Other amylases known for use in cleaning compositions include both α and β amylases. α amylases are known in the art and include those described in US Patent No. 5,003,257; EP 252 666; WO 91/00353; FR 2,676,456; EP 285 123; EP 525 610; EP 368 341; and British Patent Specification No. 1,296,839 (Novo). Other suitable amylases are the stability-enhanced amylases described in WO 94/18314 and WO 96/05295, Genecor, and amylase variants with additional modification in the immediate parent available from Novo Nordisk A/S. described in WO95/100603. Also suitable are the amylases described in EP 277 216 (Novo Nordisk). Examples of commercial α-amylase products are Purafect Ox Am® from Genencor and Termamyl®, Ban®, Fungamyl®, and Duramyl®, all available from Novo Nordisk A/S. Denmark. WO 95/26397 describes further suitable amylases: α-amylases which are characterized by having a specific activity which is at least 25% higher than the specific activity of Termamyl® at a temperature range of 25°C to 55°C and a pH in the range of 8 to 10, measured by Phadebas® α-amylase activity assay. Suitable variants of the above enzymes are those described in WO 96/23873 (Novo Nordisk). Further amylolytic enzymes with improved properties in terms of the level of activity and the combination of thermostability and a higher level of activity are described in WO 95/35382. Preferred complementary amylases for the purposes of the invention are those sold under the trade name Purafect Ox Am® described in WO 94/18314, WO 96/05295, sold by Genencor; Thermamyl®, Fungamyl®, Ban®. Natalase® and Duramyl®, all available from Novo Nordisk A/S and Maxamyl® from Gist-Brocades.

This complementary amylase is generally incorporated into the detergent compositions of the invention in a proportion of from 0.0001% to 2%, preferably from 0.00018% to 0.06%, more preferably from 0.00024% to 0.048%, pure enzyme, based on the weight of the composition. Preferably, the weight ratio of pure enzyme specific amylase to the complementary amylase is between 9:1 to 1:9, more preferably between 4:1 to 1:4, and most preferably between 2:1 and 1:2.

The above mentioned enzymes can be of any suitable origin, such as plant, animal, bacterial, fungal and yeast origin. The origin can further be mesophilic or extremophilic (psychrophilic, psychrotrophic, thermophilic, barophilic, alkalophilic, acidophilic, halogenophilic etc.). Purified or non-purified forms of these enzymes can be used. Also included by definition are mutants of native enzymes. Mutants can be obtained, for example, by protein and/or genetic engineering, chemical and/or physical modifications of native enzymes. It is also common practice to express the enzyme via white organisms in which the genetic material responsible for the production of the enzyme has been cloned. These enzymes are normally incorporated into the washing or cleaning composition in proportions of 0.0001% to 2% active enzyme, based on the weight of the cleaning composition. The enzymes can be added as separate individual components (prills, granules, stabilized liquids, etc., containing an enzyme) or as mixtures of two or more enzymes (e.g. cogranules).

Other suitable detergent ingredients that can be added are enzyme oxidation scavengers, which are described in the co-pending European patent application EP-A-0 553 607, filed on January 31, 1992. Examples of such enzyme oxidation scavengers are ethoxylated tetraethylene polyamines.

A range of enzyme materials and means for incorporating them into synthetic detergent compositions are also described in WO 9307263 A and WO 9307260 A to Genenocr International, WO 8908694 A to Novo and US 3,553,139, January 5, 1971, to McCarty et al. Enzymes are further described in US 4,101,457, Place et al. July 18, 1978, and in US 4,507,219, Hughes, March 26, 1985. Enzyme materials suitable for liquid detergent preparations and their incorporation into such preparations are described in US 4,261,868, Hora et al. April 14, 1981. Enzymes for use in detergents can be stabilized by numerous techniques. Enzyme stabilization techniques are described and exemplified in US 3,600,319, August 17, 1971, Gedge et al. EP 199 405 and EP 200 586, October 29, 1986, Venegas. Enzyme stabilization systems are also described, for example, in US 3,519,570. A useful bacillus, sp. AC13, which yields proteases, xylanases and cellulases is described in WO 9401532 A to Novo.

Bleach

A highly preferred component of the detergent component composition is a bleaching agent. Suitable bleaching agents include chlorine and oxygen releasing bleaching agents.

In a preferred aspect, the oxygen-releasing bleach contains a hydrogen peroxide source and an organic peroxyacid bleach precursor compound. Production of the organic peroxyacid occurs by an in situ reaction of the precursor with a hydrogen peroxide source. Preferred hydrogen peroxide sources include inorganic perhydrate bleaches. In an alternative preferred aspect, a preformed organic peroxyacid is incorporated directly into the composition. Also contemplated are compositions containing mixtures of a hydrogen peroxide source and an organic peroxyacid precursor in combination with a preformed organic peroxyacid.

Inorganic perhydrate bleaches

The detergent component compositions preferably contain a hydrogen peroxide source as an oxygen-releasing bleach. Suitable hydrogen peroxide sources include the inorganic perhydrate salts.

The inorganic perhydrate salts are normally incorporated in the form of the sodium salt in an amount of 1 to 40% by weight, more preferably 2 to 30% by weight, and most preferably 5 to 25% by weight of the composition.

Examples of inorganic perhydrate salts include perborate, percarbonate, perphosphate, persulfate and persilicate salts. The inorganic perhydrate salts are normally the alkali metal salts. The inorganic perhydrate salt may be included as a crystalline solid without additional protection. However, for certain perhydrate salts, the preferred embodiments of such granular compositions employ a coated form of the material which provides better storage stability for the perhydrate salt in the granular product.

Sodium perborate can exist in the form of the monohydrate of nominal formula NaBO₂H₂O₂ or the tetrahydrate NaBO₂H₂O₂·3H₂O.

Alkali metal percarbonates, particularly sodium percarbonate, are preferred perhydrates for incorporation into the compositions of the invention. Sodium percarbonate is an addition compound having a formula corresponding to 2Na₂CO₃·3H₂O₂ and is commercially available as a crystalline solid. Sodium percarbonate, being a hydrogen peroxide addition compound, tends to release the hydrogen peroxide very rapidly upon dissolution, which may increase the tendency to provide localized high bleach concentrations. The percarbonate is most commonly used in such compositions. preferably in a coated form, which provides stability within the product.

A suitable coating material for providing stability within the product comprises a mixed salt of a water-soluble alkali metal sulphate and carbonate. Such coatings, together with coating methods, have been previously described in GB 1,466,799, issued to Interox on 9 March 1977. The weight ratio of the mixed salt coating material to percarbonate is in the range 1:200 to 1:4, more preferably 1:99 to 1:9, and most preferably 1:49 to 1:19. Preferably the mixed salt consists of sodium sulphate and sodium carbonate having the general formula Na₂SO₄·n·Na₂CO₃, where n is 0.1 to 3, preferably 0.3 to 1.4, most preferably 0.2 to 0.5. Another suitable coating material which provides stability within the product comprises sodium silicate having a SiO:Na₂O ratio of 1.8:1 to 3.0:1, preferably 1.8:1 to 2.4:1, and/or sodium metasilicate, preferably applied in an amount of 2% to 10% (normally 3% to 5%) of SiO₂ based on the weight of the inorganic perhydrate salt. Magnesium silicate may also be included in the coating. Coatings containing silicate and borate salts or boric acids or other inorganic materials are also suitable.

Other coatings containing waxes, oils, fatty soaps can also be used advantageously in the present invention.

Potassium peroxymonopersulfate is another inorganic perhydrate salt with utility in the compositions described here.

Peroxyacid bleach precursor

Peroxyacid bleach precursors are compounds which react with hydrogen peroxide in a perhydrolysis reaction to produce a peroxyacid. In general, peroxyacid bleach precursors can be used as

where L is a leaving group and X essentially represents any functionality such that upon perhydrolysis the structure of the peroxyacid produced

corresponds.

Peroxyacid bleach precursor compounds are preferably incorporated at a level of 0.5 to 20%, more preferably 1 to 10%, most preferably 1.5 to 5% by weight of the compositions.

Suitable peroxyacid bleach precursor compounds typically contain one or more N- or O-acyl groups, such precursors being able to be selected from a wide range of classes. Suitable classes include anhydrides, esters, imides, lactams and acylated derivatives of imidazoles and oximes. Examples of suitable materials within these classes are described in GB-A-1586789. Suitable esters are described in GB-A-836988, 864798, 1147871, 2143231 and EP-A-0170386.

Leaving groups

The leaving group, hereinafter L-group, must be sufficiently active for the perhydrolysis reaction to occur within the optimum time frame (e.g. a wash cycle). However, if L is too reactive, this activator is not suitable for use in a bleaching composition be difficult to stabilize.

Preferred L-groups are chosen from the group consisting of:

and mixtures thereof, wherein R¹ is an alkyl, aryl or alkaryl group having 1 to 14 carbon atoms, R³ is an alkyl chain having 1 to 8 carbon atoms, R⁴ is H or R³, R⁵ is an alkenyl chain having 1 to 8 carbon atoms, and Y is H or a solubilizing group. Each of R¹, R³ and R⁴ can be substituted by essentially any functional group, including, for example, alkyl, hydroxy, alkoxy, halogen, amine, nitrosyl, amide and ammonium or alkylammonium groups.

The preferred solubilizing groups are -SO₃⁻M⁺, -CO₂⁻M⁺, -SO₄⁻M⁺, -N⁻(R³)₄X⁻ and O<--N(R³)₃, and most preferred

-SO₃⁻M⁺ and -CO₂⁻M⁺, wherein R³ is an alkyl chain having 1 to 4 carbon atoms, M is a cation which imparts solubility to the bleach activator, and X is an anion which imparts solubility to the bleach activator. Preferably, M is an alkali metal, ammonium or substituted ammonium cation, with sodium and potassium being most preferred, and X is a halide, hydroxide, methyl sulfate or acetate anion.

Perbenzoic acid precursors

Perbenzoic acid precursor compounds yield perbenzoic acid upon perhydrolysis.

Suitable O-acylated perbenzoic acid precursor compounds include the substituted and unsubstituted benzoyloxybenzenesulfonates, including, for example, benzoyloxybenzenesulfonate:

Also suitable are the benzoylation products of sorbitol, glucose and all saccharides with benzoylating agents, for example

Ac = COCH3; Bz = benzoyl

Perbenzoic acid precursors of the imide type include N-benzoylsuccinimide, tetrabenzoylethylenediamine and the N-benzoyl-substituted Ureas. Suitable perbenzoic acid precursors of the imidazole type include N-benzoylimidazole and N-benzoylbenzimidazole, and other suitable N-acyl group-containing perbenzoic acid precursors include N-benzoylpyrrolidone, dibenzoyltaurine and benzoylpyroglutamic acid. Other perbenzoic acid precursors include the benzoyldiacyl peroxides, the benzoyltetraacyl peroxides and the compound of the formula:

Phthalic anhydride is another suitable perbenzoic acid precursor compound herein:

Suitable N-acylated lactamperbenzoic acid precursors have the formula:

wherein n is 0 to 8, preferably 0 to 2, and R6 is a benzoyl group.

Perbenzoic acid derivative precursor

Perbenzoic acid derivative precursors yield substituted perbenzoic acids upon perhydrolysis.

Suitable substituted perbenzoic acid derivative precursors include any of the perbenzoic acid precursors described herein in which the benzoyl group is substituted by substantially any non-positively charged (i.e., non-cationic) functional group, including, for example, alkyl, hydroxy, alkoxy, halogen, amine, nitrosyl, and amide groups.

A preferred class of substituted perbenzoic acid precursor compounds are the amide-substituted compounds of the following general formulas:

wherein R¹ is an aryl or alkaryl group having 1 to 14 carbon atoms, R² is an arylene or alkarylene group having 1 to 14 carbon atoms, and R⁵ is H or an alkyl, aryl or alkaryl group having 1 to 10 carbon atoms, and L can be essentially any leaving group. R¹ preferably contains 6 to 12 carbon atoms. R² preferably contains 4 to 8 carbon atoms. R¹ can be aryl, substituted aryl or alkylaryl containing branching, substitution, or both, and can be derived from either synthetic sources or natural sources, including, for example, tallow fat. Analogous structural variations are possible for R². Substitution can include alkyl, aryl, halogen, nitrogen, sulfur and other typical substituent groups or organic compounds. R⁵ is preferably H or methyl. R¹ and R⁵ should contain not more than 18 carbon atoms in total. Amide-substituted bleach activator compounds of this type are described in EP-A-0170386.

Cationic peroxyacid precursors

Cationic peroxyacid precursors generate cationic peroxyacids upon perhydrolysis.

Typically, cationic peroxyacid precursors are formed by substituting the peroxyacid portion of a suitable peroxyacid precursor compound with a positively charged functional group such as an ammonium or alkylammonium group, preferably an ethyl or methylammonium group. Cationic peroxyacid precursors are typically present in the compositions as a salt with a suitable anion such as a halide ion or a methyl sulfate ion.

The peroxyacid precursor compound to be cationically substituted in this manner may be a perbenzoic acid precursor compound or a substituted derivative thereof as described above. Alternatively, the peroxyacid precursor compound may be an alkylpercarboxylic acid precursor compound or an amide-substituted alkylperoxyacid precursor as described below.

Cationic peroxyacid precursors are described in US patents 4,904,406; 4,751,015; 4,988,451; 4,397,757; 5,269,962; 5,127,852; 5,093,022; 5,106,528; UK 1,382,594; EP 475,512, 458,396 and 284,292; and in JP 87-318,332.

Suitable cationic peroxyacid precursors include any of the ammonium or alkylammonium substituted alkyl or benzoyloxybenzene sulfonates, N-acylated caprolactams, and monobenzoyltetraacetylglucose benzoyl peroxides.

A preferred cationically substituted benzoyloxybenzenesulfonate is the 4-(trimethylammonium)methyl derivative of benzoyloxybenzenesulfonate:

A preferred cationically substituted alkyloxybenzenesulfonate has the formula:

Preferred cationic peroxyacid precursors from the N-acylated caprolactam class include the trialkylammonium methylenebenzoylcaprolactams, particularly trimethylammonium methylenebenzoylcaprolactam:

Other preferred cationic peroxyacid precursors of the N-acylated caprolactam class include the trialkylammonium methylene alkyl caprolactams:

wherein n is 0 to 12, preferably 1 to 5.

Another preferred cationic peroxyacid precursor is 2-(N,N,N-trimethylammonium)ethylsodium 4-sulfophenyl carbonate chloride.

Alkylpercarboxylic acid bleach precursors

Alkyl percarboxylic acid bleach precursors form percarboxylic acids upon perhydrolysis. Preferred precursors of this type form peracetic acid upon perhydrolysis.

Preferred imide-type alkylpercarboxylic acid precursor compounds include the N,N,N¹N¹-tetraacetylated alkylenediamines wherein the alkylene group contains 1 to 6 carbon atoms, particularly those compounds wherein the alkylene group contains 1, 2 and 6 carbon atoms. Tetraacetylethylenediamine (TAED) is particularly preferred.

Other preferred alkyl percarboxylic acid precursors include sodium 3,5,5-trimethylhexanoyloxybenzenesulfonate (iso-NOBS), sodium nonanoyloxybenzenesulfonate (NOBS), sodium acetoxybenzenesulfonate (ABS), and pentaacetylglucose.

Amide-substituted alkyl peroxyacid precursors

Amide-substituted alkyl peroxyacid precursor compounds are also suitable, including those of the following general formulas:

wherein R¹ is an alkyl group having 1 to 14 carbon atoms, R² is an alkylene group having 1 to 14 carbon atoms, and R⁵ is H or an alkyl group having 1 to 10 carbon atoms, and L is essentially any alkylene group having 1 to 14 carbon atoms, and R⁵ is H or an alkyl group having 1 to 10 carbon atoms, and L can be essentially any leaving group. R¹ preferably contains 6 to 12 carbon atoms. R² preferably contains 4 to 8 carbon atoms. R¹ can be straight chain or branched alkyl containing branching, substitution or both and can be derived from either synthetic sources or natural sources including, for example, tallow fat. Analogous structural variations are possible for R². Substitution can include alkyl, halogen, nitrogen, sulphur and other typical substituent groups or organic compounds. R⁵ is preferably H or methyl. R¹ and R⁵ should not contain more than 18 carbon atoms in total. Amide substituted bleach activator compounds of this type are described in EP-A-0170386.

Organic peroxyacid precursors of the benzoxazine type

Also suitable are precursor compounds of the benzoxazine type, as described for example in EP-A-332,294 and EP-A-482,807, in particular those of the formula:

including substituted benzoxazines of the type

wherein R₁ is H, alkyl, alkaryl, aryl, arylalkyl, and wherein R₂, R₃, R₄ and R₅ may be the same or different substituents selected from H, Halogen, alkyl, alkenyl, aryl, hydroxyl, alkoxyl, amino, alkylamino, COOR₆ (wherein R₆ is H or an alkyl group) and carbonyl functions.

A particularly preferred precursor of the benzoxazine type is:

Preformed organic peracid

The organic peroxyacid bleach system may contain, in addition to or as an alternative to an organic peroxyacid bleach precursor compound, a preformed organic peroxyacid, typically in a proportion of from 0.5 to 25%, more preferably from 1 to 10%, by weight of the composition.

A preferred class of organic peroxyacid compounds are the amide-substituted compounds of the following general formulas:

wherein R¹ is an alkyl, aryl or alkaryl group having 1 to 14 carbon atoms, R² is an alkylene, arylene or alkarylene group having 1 to 14 carbon atoms, and R⁵ is H or an alkyl, aryl or alkaryl group having 1 to 10 carbon atoms. R¹ preferably contains 6 to 12 carbon atoms. R² preferably contains 4 to 8 carbon atoms. R¹ may be straight chain or branched alkyl, substituted aryl or alkylaryl containing branching, substitution, or both, and may be derived from either synthetic sources or natural sources including, for example, tallow fat. Analogous structural variations are possible for R². Substitution may include alkyl, aryl, halogen, nitrogen, sulfur and other typical substituent groups or organic compounds. R⁵ is preferably or methyl. R¹ and R⁵ should not contain more than 18 carbon atoms in total. Amide substituted organic peroxyacid compounds of this type are described in EP-A-0170386.

Other organic peroxyacids include diacyl and tetraacyl peroxides, especially diperoxydodecanedioic acid, diperoxytetradecanedioic acid and diperoxyhexadecanedioic acid. Dibenzoyl peroxide is a preferred organic peroxyacid herein. Mono- and diperazelaic acid, mono- and diperbrassylic acid, and N-phthaloylaminoperoxycaproic acid are also suitable herein.

Regulated rate release agent

A means may be provided to regulate the rate of release of a bleaching agent, particularly oxygen bleach, to the washing solution.

Means for controlling the release rate of the bleaching agent may provide a controlled release of the peroxide species to the wash solution. Such means may, for example, include controlling the release of any inorganic perhydrate salt serving as a hydrogen peroxide source to the wash solution.

Another mechanism for regulating the release rate of the bleach can be achieved by coating the bleach with a Coating designed to provide controlled release. The coating may therefore comprise, for example, a slightly water soluble material or may be a coating of sufficient thickness so that the dissolution kinetics of the thick coating provide the controlled release rate. The coating material may be applied using a variety of methods. A coating material is typically present in a weight ratio of coating material to bleach of 1:99 to 1:2, preferably 1:49 to 1:9.

Suitable coating materials include triglycerides (e.g. partially hydrogenated vegetable oil, soybean oil, cottonseed oil) mono- or diglycerides, microcrystalline waxes, gelatin, cellulose, fatty acids and any mixtures thereof.

Other suitable coating materials may include the alkali and alkaline ore metal sulfates, silicates and carbonates, including calcium carbonate and silicas.

A preferred coating material, particularly for an inorganic perhydrate salt bleach source, comprises sodium silicate having a SiO2:Na2O ratio of 1.8:1 to 3.0:1, preferably 1.8:1 to 2.4:1, and/or sodium metasilicate, preferably applied in a proportion of 2 to 10% (normally 3 to 5%) of SiO2 based on the weight of the inorganic perhydrate salt. Magnesium silicate may also be included in the coating.

Any inorganic salt coating materials can be combined with organic binder materials to provide inorganic salt-organic binder composite coatings. Suitable binders include the C10-C20 alcohol ethoxylates containing 5-100 moles of ethylene oxide per mole of alcohol, and more preferably the C15-C20 primary alcohol ethoxylates containing 20-100 moles of ethylene oxide per mole of alcohol.

Other preferred binders include certain polymeric materials. Polyvinylpyrrolidones having an average molecular weight of 12,000 to 700,000 and polyethylene glycols (PEG) having an average molecular weight of 600 to 5 x 106, preferably 1,000 to 400,000, most preferably 1,000 to 10,000, are examples of such polymeric materials.

Copolymers of maleic anhydride with ethylene, methyl vinyl ether or methacrylic acid, wherein the maleic anhydride constitutes at least 20 mole percent of the polymer, are further examples of polymeric materials suitable as binders. These polymeric materials can be used as such or in combination with solvents such as water, propylene glycol and the above-mentioned C10-C20 alcohol ethoxylates containing 5-100 moles of ethylene oxide per mole. Further examples of binders include the C10-C20 mono- and diglycerol ethers and also the C10-C20 fatty acids.

Cellulose derivatives such as methylcellulose, carboxymethylcellulose and hydroxyethylcellulose, and homo- or copolymeric polycarboxylic acids or their salts are further examples of binders suitable for use herein.

One method of applying the coating material involves agglomeration. Preferred agglomeration methods include using any of the organic binder materials described above. A conventional agglomerator/mixer can be used, including, but not limited to, pan, rotary roll and vertical type mixers. Molten coating compositions can also be applied, either by pouring onto or spray atomizing onto a moving bed of bleach.

Other means of providing the desired controlled release include mechanical means of changing the physical characteristics of the bleaching agents to regulate their solubility and release rate. Suitable protocols could include compression, mechanical injection, manual injection, and adjustment of the solubility of the bleaching compound by selection of the particle size of any particulate component.

While the choice of particle size depends on both the composition of the particulate component and the desire to meet the desired controlled release kinetics, it is desirable that the particle size should be greater than 500 µm, preferably with an average particle diameter of 800 to 1,200 µm.

Additional protocols for providing the means of controlled release include the appropriate selection of any other components of the detergent composition matrix so that when the composition is introduced into the wash solution, the ionic strength environment provided therein enables the required kinetics of controlled release to be achieved.

Metal-containing bleach catalyst

The compositions described herein which contain a bleach as a detergent component can additionally contain a metal-containing bleach or bleach catalyst as a preferred component. The metal-containing bleach catalyst is preferably a transition metal-containing bleach catalyst, more preferably a manganese- or cobalt-containing bleach catalyst.

A suitable type of bleach catalyst is a catalyst comprising a heavy metal cation with defined catalytic bleaching activity, such as copper, iron cations, and auxiliary metal cations with little or no catalytic bleaching activity, such as zinc or aluminum cations, and a complexing agent with defined stability constants for the catalytic and auxiliary metal cations, particularly ethylenediaminetetraacetic acid, ethylenediaminetetra(methylenephosphonic acid) and water-soluble salts thereof. Such catalysts are described in US Patent 4,430,243.

Preferred types of bleach catalysts include the manganese-based complexes described in U.S. Patent 5,246,621 and U.S. Patent 5,244,594. Preferred examples of these catalysts include MnIV₂(u- O)₃(1,4,7-trimethyl-1,4,7-triazacyclononane)₂-(PF₆)₂, MnIII₂(u-O)₁(u-OAc)₂(1,4,7-trimethyl-1,4,7-triazacyclononane)₂-(ClO₄)₂, MnIV₄(u- O)₆(1,4,7-triazacyclononane)₄-(ClO₄)2, MnIIIMnIV₄(u-O)₁(u-OAc)₂- (1,4,7-trimethyl-1,4,7-triazacyclononane)₂-(ClO₄)₃ and mixtures thereof. Others are described in European Patent Application Publication Number 549 272. Other ligands suitable for use herein include 1,5,9-trimethyl-1,5,9-triazacyclododecane, 2-methyl-1,4,7-triazacyclononane, 2-methyl-1,4,7-triazacyclononane, 1,2,4,7-tetramethyl-1,4,7-triazacyclononane and mixtures thereof.

The bleach catalysts useful in the compositions described herein may also be selected as useful in the present invention. For examples of suitable bleach catalysts, see U.S. Patent 4,246,612 and U.S. Patent 5,227,084. See also U.S. Patent 5,194,416, which describes mononuclear manganese (IV) complexes, such as Mn(1,4,7-trimethyl-1,4,7-triazacyclononane)(OCH3)3-(PF6). Yet another type of bleach catalyst, as described in U.S. Patent 5,114,606, is a water-soluble complex of manganese (III) and/or (IV) with a ligand which is a noncarboxylate polyhydroxy compound having at least three consecutive C-OH groups. Preferred ligands include sorbitol, iditol, dulsitol, mannitol, xylitol, arabitol, adonitol, meso-erythritol, meso-inositol, lactose and mixtures thereof.

US Patent 5,114,611 describes a bleach catalyst comprising a complex of transition metals, including Mn, Co, Fe or Cu, with a non-(macro)-cyclic ligand. Such ligands have the formula:

wherein R¹, R², R³ and R⁴ may each be selected from H, substituted alkyl and aryl groups such that each R¹-N=C-R² and R³-C=N-R⁴ forms a five or six membered ring. This ring may be further substituted. B is a bridging group selected from O, S, CR⁵R⁶, NR⁷ and C=O, wherein R⁵, R⁵ and R⁴ may each be H, alkyl or aryl groups, including substituted or unsubstituted groups. Preferred ligands include pyridine, pyridazine, pyrimidine, pyrazine, imidazole, pyrazole and triazole rings. Optionally, these rings can be substituted with substituents such as alkyl, aryl, alkoxy, halide and nitro. Most preferably, the ligand is 2,2-bispyridylamine. Preferred bleach catalysts include Co, Cu, Mn, Fe, -bispyridylmethane and -bispyridylamine complexes. Highly preferred catalysts include Co(2,2'-bispyridylamine)Cl2, di(isothiocyanato)bispyridylamine cobalt(II), trisdipyridylamine cobalt(II) perchlorate, Co(2,2-bispyridylamine)O2ClO4, bis(2,2'-bispyridylamine)copper(II) perchlorate, tris(di-2-pyridylamine)iron(II) chlorate and mixtures thereof.

Preferred examples include dinuclear Mn complexes with tetra-Ndentate and Bi-N-dentate ligands, including N4MnIII(u-O)2MnIVN4)+ and [Bipy2MnIII(u-O)2MnIVbipy2)-(ClO4)3.

Although the structures of the bleach-catalyzing manganese complexes according to the present invention have not been elucidated, it can be assumed that they comprise chelates or other hydrated coordination complexes resulting from the interaction of the carboxyl and nitrogen atoms of the ligand with the manganese cation. Likewise, the oxidation state of the manganese cation during the catalytic process is not known with certainty and may assume the (+II), (+III), (+IV) or (+V) valence state. Due to the possible six binding points of the ligand to the manganese cation, It can be reasonably assumed that polynuclear species and/or "cage" structures may be present in the aqueous bleaching media. Whatever the form of the active Mn ligand species actually present, it acts in an apparent catalytic manner to provide improved bleaching performance against stubborn stains such as tea, ketchup, coffee, wine, juice and the like.

Other bleach catalysts are described, for example, in European patent application publication number 408,131 (cobalt complex catalysts), European patent applications publication numbers 384,503 and 306,089 (metallo-porphyrin catalysts), U.S. 4,728,455 (manganese/multidentate ligand catalyst), U.S. 4,711,748 and European patent application publication number 224,952 (absorbed manganese on aluminosilicate catalyst), U.S. 4,601,845 (aluminosilicate support with manganese and zinc or magnesium salt), U.S. 4,626,373 (manganese/ligand catalyst), U.S. 4,119,557 (iron (III) complex catalyst), German Patent 2,054,019 (cobalt chelate catalyst), Canada 868, 191 (transition metal containing salts), U.S. 4,430,243 (complexing agents with manganese cations and non-catalytic metal cations) and U.S. 4,728,455 (manganese gluconate catalysts).

Further preferred examples include cobalt (III) catalysts of the formula

Co[(NH₃)nM'mB'bTtQqPp]Yy

wherein cobalt is in the +3 oxidation state; n is an integer from 0 to 5 (preferably 4 or 5; most preferably 5); M' is a monodentate ligand; m is an integer from 0 to 5 (preferably 1 or 2; most preferably 1); B' is a bidentate ligand; b is an integer from 0 to 2; T' is a tridentate ligand; t is 0 or 1; Q is a tetradentate ligand; q is 0 or 1; P is a pentadentate ligand; p is 0 or 1; and n + m + 2b + 3t + 4q + 5p = 6; Y is one or more suitably chosen counter anions which in a number y, where y is an integer from 1 to 3 (preferably 2 to 3; most preferably 2 when Y is a -1 charged anion) to obtain a charge balanced salt, preferred Y being selected from the group consisting of chloride, nitrate, nitrite, sulfate, citrate, acetate, carbonate, and combinations thereof; and further wherein at least one of the coordination sites bonded to the cobalt is labile under machine dishwashing use conditions and the remaining coordination sites stabilize the cobalt under machine dishwashing conditions such that the reduction potential for cobalt (III) to cobalt (II) under alkaline conditions is less than 0.4 volts (preferably less than 0.2 volts) versus a standard hydrogen electrode.

Preferred cobalt catalysts of this type have the formula:

[Co(NH₃)n(M')m]Yy

wherein n is an integer from 3 to 5 (preferably 4 or 5; most preferably 5); M' is a labile coordination group, preferably selected from the group consisting of chlorine, bromine, hydroxide, water, and (when m is greater than 1) combinations thereof; m is an integer from 1 to 3 (preferably 1 or 2; most preferably 1); m + n = 6; and Y is a suitably selected counter anion in a number y which is an integer from 1 to 3 (preferably 2 to 3; most preferably 2 when Y is a -1 charged anion) to obtain a charge balanced salt.

The preferred cobalt catalyst of this type for use herein is cobalt pentaamine chloride salts of the formula [Co(NH3)5Cl]Yy, and especially [Co(NH3)5Cl]Cl2.

Further preferred are the compositions according to the invention in which cobalt (III) bleach catalysts of the formula:

[Co(NH₃)n(M)m(B)b]Ty

wherein cobalt is in the +3 oxidation state; n is 4 or 5 (preferably 5); M is one or more ligands coordinated with the cobalt by one site; m is 0, 1 or 2 (preferably 1); B is a ligand coordinated with the cobalt by 2 sites; b is 0 or 1 (preferably 0), and if b = 0 then m + n = 6, and if b = 1 then m = 0 and n = 4; and T is one or more suitably chosen counter anions in a number y, where y is an integer to obtain a charge balanced salt (preferably y is 1 to 3; most preferably 2 if T is a -1 charged anion); and further wherein the catalyst has a base hydrolysis rate constant of less than 0.23 M⁻¹ s⁻¹ (25°C).

Preferred T are selected from the group consisting of chloride, iodide, I₃⁻, formate, nitrate, nitrite, sulfate, sulfide, citrate, acetate, carbonate, bromide, F₆⁻, BF₄⁻, B(Ph)₄⁻, phosphate, phosphite, silicates, tosylate, methanesulfonate, and combinations thereof. Optionally, T may be protonated if more than one anionic group is present in T, for example, HPO₄²⁻, HCO₃⁻, H₂PO₄⁻ etc. Furthermore, T can be selected from the group consisting of non-traditional inorganic anions, such as anionic surfactants (e.g. linear alkylbenzenesulfonates (LAS), alkyl sulfates (AS), alkylethoxysulfonates (AES), etc.) and/or anionic polymers (e.g. polyacrylates, polymethacrylates, etc.).

The M groups include, but are not limited to, for example, F-, SO₄⁻², NCS⁻, SCN⁻, S₂O₃⁻², NH₃, PO₄³⁻, and carboxylates (which are preferably monocarboxylates, but there may be more than one carboxylate in the group so long as the bond to the cobalt is through only one carboxylate per group, in which case the other carboxylate in the M group may be protonated or in its salt form). Optionally, M may be protonated if there is more than one anionic group in M (for example, HPO₄²⁻, HCO₃⁻, H₂PO₄-, HOC(O)CH₂C(O)-, etc.). Preferred M groups are substituted and unsubstituted C₁- C₃�0 carboxylic acids of the formulas:

RC(O)O-

wherein R is preferably selected from the group consisting of hydrogen and unsubstituted and substituted C₁-C₃�0 (preferably C₁-C₁₈)alkyl, unsubstituted and substituted C₆-C₃�0 (preferably C₆-C₁₈)aryl and unsubstituted and substituted C₃-C₃�0 (preferably C5-C18)heteroaryl, wherein substituents are selected from the group consisting of -NR'3, NR'4+, -C(O)OR', -OR', -C(O)NR'2, wherein R' is selected from the group consisting of hydrogen and C1-C6 groups. Such substituted R therefore include the groups -(CH2)nOH and -(CH2)nNR'4+, wherein n is an integer from 1 to 16, preferably 2 to 10, most preferably 2 to 5.

Most preferred M are carboxylic acids of the above formula, where R is selected from the group consisting of hydrogen, methyl, ethyl, propyl, straight or branched C4-C12 alkyl and benzyl. Most preferably R is methyl. Preferred carboxylic acid M groups include formic, benzoic, octanoic, nonanoic, decanoic, dodecanoic, malonic, maleic, succinic, adipic, phthalic, 2-ethylhexanoic, naphthenic, oleic, palmitic, triflate, tartrate, stearic, butyric, citric, acrylic, aspartic, fumaric, lauric, linoleic, lactic, malic and especially acetic acid.

The B groups include carbonate, di- and higher carboxylates (e.g. oxalate, malonate, malic acid, succinate, maleate), picolinic acid and alpha- and beta-amino acids (e.g. glycine, alanine, beta- alanine, phenylalanine).

Cobalt bleach catalysts suitable for this purpose are known and are described, for example, together with their base hydrolysis rates in ML Tobe, "Base Hydrolysis of Trasition-Metal Complexes", Adv. Inorg. Bioinoinorg. Mech., (1983), 2, pages 1-94. For example, Table 1 on page 17 shows the base hydrolysis rates (therein as kOH for cobalt pentaamine catalysts complexed with oxalate (kOH = 2.5 · 10⁻⁴ M-1 s⁻¹ (25ºC)), NCS⁻ (kOH = 5.0 · 10⁻⁴ M⁻¹ s⁻¹ (25ºC)), formate (kOH = 5.8 · 10⁻⁴ M⁻¹ s⁻¹ (25ºC)), and acetate (kOH = 9.6 · 10⁻⁴ M⁻¹ s⁻¹ (25ºC)). The most preferred cobalt catalyst useful herein are cobalt pentaamine acetate salts of the formula [Co(NH3)5OAc]Ty, where OAc represents an acetate group, and particularly cobalt pentaamine acetate chloride, [Co(NH3)5OAc]Cl2; and [Co(NH3)5OAc](OAc)2; (Co(NH3)5OAc](PF6)2; [Co(NH3)5OAc](SO4); [Co(NH3)5OAc](BF4)2; and [Co(NH3)5OAc](NO3)2 (hereinafter "PAC").

These cobalt catalysts are readily prepared by known methods, such as in the above-mentioned Tobe article and the references cited therein, in U.S. Patent 4,810,410 to Diakun et al., issued March 7, 1989, J. Chem. Ed. (1989), 66 (12), 1043-45; The Synthesis and Characterization of Inorganic Compounds, W. L. Jolly (Prentice-Hall; 1970), pp. 461-3; Inorg. Chem., 18, 1497-1502 (1979); Inorg. Chem., 21, 2881-2885 (1982); Inorg. Chem 18 2023-2025 (1979); Inorg. Synthesis, 173-176 (1960); and Journal of Physical Chemistry, 56, 22-25 (1952); and the synthesis examples given below.

Cobalt catalysts suitable for incorporation into the detergent tablets of the invention can be prepared according to the synthesis routes described in U.S. Patent Nos. 5,559,261, 5,581,005, and 5,597,936.

These catalysts can be co-processed with auxiliary materials so as to reduce the color impact if desired for the aesthetics of the product, or can be included in enzyme-containing particles as illustrated below, or the compositions can be prepared to contain catalyst "spots".

Organic polymeric compounds

Organic polymeric compounds may be added as preferred components of the detergent tablets according to the invention. By organic polymeric compound is meant essentially any polymeric organic compound commonly found in detergent compositions which has dispersing, anti-redeposition, soil release or other detergent properties.

The organic polymeric compound is typically incorporated into the detergent compositions of the invention in an amount of from 0.1 to 30%, preferably from 0.5 to 15%, most preferably from 1 to 10%, by weight of the compositions.

Examples of the organic polymeric compounds include the water-soluble organic homo- or copolymeric polycarboxylic acids, modified polycarboxylates or their salts, wherein the polycarboxylic acid comprising at least two carboxyl radicals separated from each other by not more than two carbon atoms. Polymers of the latter type are described in GB-A-1,596,756. Examples of such salts are polyacrylates having a molecular weight of 2,000-10,000 and their copolymers with any suitable other monomer units, including modified acrylic, fumaric, maleic, itaconic, aconitic, mesaconic, citraconic and methylenemalonic acids or their salts, maleic anhydride, acrylamide, alkylene, vinyl methyl ether, styrene and any mixtures thereof. Preferred are copolymers of acrylic acid and maleic anhydride with a molecular weight of 20,000 to 100,000.

Preferred commercially available acrylic acid-containing polymers with a molecular weight below 15,000 include those sold under the trade name Sokalan PA30, PA20, PA15, PA10 and Sokalan CP10 by BASF GmbH, and those sold under the trade name Acusol 45N, 480N, 460N by Rohm and Haas.

Preferred acrylic acid-containing copolymers include those containing as monomer units: a) 90 to 10% by weight, preferably 80 to 20% by weight, acrylic acid or its salts, and b) 10 to 90% by weight, preferably 20 to 80% by weight, of a substituted acrylic monomer or its salts of the general formula -[CR₂-CR₁(CO-O-R₃)]-, wherein at least one of the substituents R₁, R₂ or R₃, preferably R₁ or R₂, is an alkyl or hydroxyalkyl group having 1 to 4 carbons, R₁ or R₂ can be a hydrogen, and R₃ can be a hydrogen or alkali metal salt. Most preferred is a substituted acrylic monomer wherein R₁ is is methyl, R2 is hydrogen (i.e., a methacrylic acid monomer). The most preferred copolymer of this type has a molecular weight of 3,500 and contains 60 to 80 wt.% acrylic acid and 40 to 20 wt.% methacrylic acid.

The polyamine and modified polyamine compounds are useful herein, including those derived from aspartic acid as described in EP-A-305282, EP-A-305283 and EP-A-351629.

Other optional polymers include polyvinyl alcohols and acetates, both modified and unmodified, cellulosics and modified cellulosics, polyoxyethylenes, polyoxypropylenes and copolymers thereof, both modified and unmodified, terephthalate esters of ethylene or propylene glycol or mixtures thereof with polyoxyalkylene units.

Suitable examples are described in U.S. Patent Nos. 5,591,703, 5,597,789 and 4,490,271.

Dirt repellents

Suitable polymeric soil release agents include those soil release agents which: (a) comprise one or more nonionic hydrophilic components consisting essentially of (i) polyoxyethylene segments having a degree of polymerization of at least 2 or (ii) oxypropylene or polyoxypropylene segments having a degree of polymerization of from 2 to 10, wherein the hydrophilic segment does not include an oxypropylene unit unless it is linked to adjacent groups at each end by ether linkages, or (iii) a mixture of oxyalkylene units comprising oxyethylene and from 1 to 30 oxypropylene units, wherein the hydrophilic segments preferably comprise at least 25% oxyethylene units and more preferably, particularly for those components having from 20 to 30 oxypropylene units, at least 50% oxyethylene units; or (b) one or more hydrophobic components comprising (i) C₃-oxyalkylene terephthalate segments, wherein, when the hydrophobic components also comprise oxyethylene terephthalate, the ratio of oxyethylene terephthalate: C₃-oxyalkylene terephthalate units is 2:1 or less, (ii) C₄-C₆-alkylene or oxy-C₄-C₆-alkylene segments or mixtures therein, (iii) poly(vinyl ester) segments, preferably polyvinyl acetate, having a degree of polymerization of at least 2, or (iv) C₁-C₄-alkyl ether or C₄-hydroxyalkyl ether substituents or mixtures therein, wherein the substituents are in the form of C₁-C₄-alkyl ether or C₄-hydroxyalkyl ether cellulose derivatives or mixtures thereof, or a combination of (a) and (b).

Typically, the polyoxyethylene segments of (a)(i) have a degree of polymerization of 200, although higher degrees can be used, preferably 3 to 150, more preferably 6 to 100. Suitable hydrophobic oxy-C4-C6 alkylene segments include, but are not limited to, end caps of polymeric soil release agents such as MO3S(CH2)nOCH2CH2O-, where M is sodium and n is an integer from 4-6, as described in U.S. Patent 4,721,580, issued January 26, 1988 to Gosselink.

Polymeric soil release agents useful herein also include cellulosic derivatives such as hydroxyether cellulose polymers, copolymeric blocks of ethylene terephthalate or propylene terephthalate with polyethylene oxide or polypropylene oxide terephthalate, and the like. Such Agents are commercially available and include hydroxy ethers of cellulose such as METHOCEL (Dow). Cellulosic soil release agents for use herein also include those selected from the group consisting of C1 -C4 alkyl and C4 hydroxyalkyl cellulose; see U.S. Patent 4,000,093, issued December 28, 1976 to Nicol et al.

Soil release agents characterized by hydrophobic poly(vinyl ester) segments include graft copolymers of poly(vinyl ester), e.g. C1-C6 vinyl esters, preferably polyvinyl acetate, grafted to polyalkylene oxide backbones, such as polyethylene oxide backbones. See European Patent Application 0 219 048, published April 22, 1987, by Kud et al.

Another suitable soil release agent is a random block copolymer of ethylene terephthalate and polyethylene oxide (PEO) terephthalate. The molecular weight of this polymeric soil release agent is in the range of 25,000 to 55,000; see U.S. Patent 3,959,230 to Hays, issued May 25, 1976 and U.S. Patent 3,893,929 to Basadur, issued July 8, 1975.

Another suitable polymeric soil release agent is a polyester having repeating units of ethylene terephthalate units containing 10-15 wt.% ethylene terephthalate units together with 90-80 wt.% polyoxyethylene terephthalate units derived from polyoxyethylene glycol having an average molecular weight of 300-5,000.

Another suitable polymeric soil release agent is a sulfonated product of a substantially linear ester oligomer comprising an oligomeric ester backbone of repeating terephthaloyl and oxyalkyleneoxy units and end groups covalently bonded to the backbone. These soil release agents are fully described in U.S. Patent 4,968,451, issued November 6, 1990 to JJ Scheibel and EP Gosselink. Other suitable polymeric soil release agents include the terephthalate polyesters of U.S. Patent 4,711,730, issued December 8, 1987 to Gosselink et al., the anionic end-capped oligomeric esters of U.S. Patent 4,721,580, issued January 26, 1988 to Gosselink, and the oligomeric block polyester compounds of U.S. Patent 4,702,857, issued October 27, 1987 to Gosselink. Other polymeric soil release agents also include the soil release agents of U.S. Patent 4,877,896, issued October 31, 1989 to Maldonado et al., which describes anionic, particularly sulfarolyl, end-capped terephthalate esters.

Another soil release agent is an oligomer having repeating units of terephthaloyl units, sulfoisoterephthaloyl units, oxyethyleneoxy and oxy-1,2-propylene units. These repeating units form the backbone of the oligomer and are preferably terminated with modified isethionate end caps. A particularly preferred soil release agent of this type comprises one sulfoisophthaloyl unit, five terephthaloyl units, oxyethyleneoxy and oxy-1,2-propyleneoxy units in a ratio of 1.7 to 1.8, and two end capping units of sodium 2-(2-hydroxyethoxy)ethanesulfonate.

Heavy metal ion complexing agents

The tablets according to the invention preferably contain a heavy metal ion complexing agent as an optional component. By heavy metal ion complexing agents are meant here components which act to sequester or mask (chelate) heavy metal ions. These components can also have calcium and magnesium chelating ability, but they preferably show selectivity for binding heavy metal ions such as iron, manganese and copper.

Heavy metal ion complexing agents are generally present in a proportion of 0.005 to 20%, preferably 0.1 to 10%, more preferably 0.25 to 7.5%, and most preferably 0.5 to 5%, by weight of the compositions.

Heavy metal ion complexing agents which are acidic in nature, with, for example, phosphonic acid or carboxylic acid functionalities, may be present either in their acid form or as a complex/salt with a suitable counter cation, such as an alkali or alkali metal ion, ammonium or substituted ammonium ion, or any mixture thereof. Preferably, the salts/complexes are water soluble. The molar ratio of the counter cation to the heavy metal ion complexing agent is preferably at least 1:1.

Suitable heavy metal ion chelating agents for use herein include organic phosphonates such as the aminoalkylene poly(alkylene phosphonates), alkali metal ethane-1-hydroxydiphosphonates and nitrilotrimethylene phosphonates. Preferred among the above species are diethylenetriamine penta(methylenephosphonate), ethylenediamine tri(methylenephosphonate), hexamethylenediamine tetra(methylenephosphonate) and hydroxyethylene-1,1-diphosphonate.

Other suitable heavy metal ion complexing agents for use herein include nitrilotriacetic acid and polyaminocarboxylic acids such as ethylenediaminetetraacetic acid, ethylenetriaminepentaacetic acid, ethylenediaminedisuccinic acid, ethylenediaminediglutaric acid, 2-hydroxypropylenediaminedisuccinic acid or any salts thereof.

Particularly preferred is ethylenediamine-N,N'-disuccinic acid (EDDS) or the alkali metal, alkaline earth metal, ammonium or substituted ammonium salts thereof, or mixtures thereof. Preferred EDDS compounds are the free acid form and the sodium or magnesium salt or complex thereof.

Crystal growth inhibitor component

The washing or cleaning agent tablets preferably contain a crystal growth inhibitor component, preferably an organodiphosphonic acid component, which is preferably incorporated in a proportion of 0.01 to 5%, more preferably 0.1 to 2%, based on the weight of the compositions.

By organodiphosphonic acid is meant here an organodiphosphonic acid that does not contain nitrogen as part of its chemical structure. This definition therefore excludes organic aminophosphonates, which, however, can be included in the compositions according to the invention as heavy metal ion complexing components.

The organodiphosphonic acid is preferably a C₁-C₄-diphosphonic acid, more preferably a C₂-diphosphonic acid, such as ethylenediphosphonic acid, or most preferably ethane-1-hydroxy-1,1-diphosphonic acid (HEDP) and may be in partially or fully ionized form, particularly as a salt or complex.

Water-soluble sulfate salt

The detergent tablet optionally contains a water-soluble sulfate salt. When present, the proportion of water-soluble sulfate salt is from 0.1 to 40%, more preferably from 1 to 30%, most preferably from 5 to 25%, by weight of the compositions.

The water-soluble sulfate salt can be essentially any salt of sulfate with any counter cation. Preferred salts are selected from the sulfates of the alkali and alkaline earth metals, especially sodium sulfate.

Alkali metal silicate

An alkali metal silicate is a preferred component of the tablet of the invention. A preferred alkali metal silicate is sodium silicate having a SiO₂:Na₂O ratio of 1.8 to 3.0, preferably 1.8 to 2.4, most preferably 2.0. Sodium silicate is preferably present in an amount of less than 20%, preferably 1 to 15%, most preferably 3 to 12%, based on the weight of SiO₂. The alkali metal silicate may be in the form of either the anhydrous salt or a hydrated salt.

Alkali metal silicates may also be present as a component of an alkalinity system.

The alkalinity system also preferably contains sodium metasilicate, present in an amount of at least 0.4 wt.% SiO₂. Sodium metasilicate has a nominal SiO₂:Na₂O ratio of 1.0. The weight ratio of the sodium silicate to the sodium metasilicate, measured as SiO₂, is preferably 50:1 to 5:4, more preferably 15:1 to 2:1, most preferably 10:1 to 5:2.

Dyes

The term "colorant" as used herein means any substance which absorbs specific wavelengths of light from the visible light spectrum. Such colorants, when added to a detergent composition, have the effect of changing the visible color and hence the appearance of the detergent composition. Colorants may, for example, be either dyes or pigments. Preferably, the colorants are stable in the composition into which they are to be incorporated. Thus, in a high pH composition, the colorant is preferably alkali stable, and in a low pH composition, the colorant is preferably acid stable.

The first and/or second and/or optionally further phases may contain a colorant, a mixture of colorants, colored particles or mixture of colored particles, so that the different phases have different visible appearances. Preferably, one of either the first or the second phase comprises a colorant. If both the first and second and/or subsequent phases comprise a colorant, it is preferred that the colorants have a different visible appearance.

Examples of suitable dyes include reactive dyes, direct dyes, azo dyes. Preferred dyes include phthalocyanine dyes, anthraquinone dyes, quinoline dyes, monoazo, disazo and polyazo. More preferred dyes include anthraquinone, quinoline and monoazo dyes. Preferred colorants include SANDOLAN E-HRL 180% (trade name), SANDOLAN MILLING BLUE (trade name), TURQUOISE, ACID BLUE (trade name) and SANDOLAN BRILLINAT GREEN (trade name), all available from Clariant UK, HEXACOL QUINOLINE YELLOW (trade name) and HEXACOL BRILLIANT BLUE (trade name), both available from Pointings, UK, ULTRA MARINE BLUE (trade name) available from Holliday or LEVAFIX TURQUISE BLUE EBA (trade name) available from Bayer, USA.

The colorant may be introduced into the phases by any suitable method. Suitable methods include mixing all or selected detergent components with a colorant in a drum or spraying all or selected detergent components with the colorant in a rotating drum.

The colorant, when present as a component of the first phase, is present in a proportion of 0.001 to 1.5%, preferably 0.01 to 1.0%, most preferably 0.1 to 0.3%. When present as a component of the second and/or optional further phases, the colorant is generally present in a proportion of 0.001 to 0.1%, more preferably 0.005 to 0.05%, most preferably 0.007 to 0.02%.

Corrosion inhibitor compound

The tablets according to the invention suitable for use in dishwashing processes can contain corrosion inhibitors, preferably selected from organic silver coating agents, in particular paraffin, nitrogen-containing corrosion inhibitor compounds and Mn(II) compounds, in particular Mn(II) salts of organic ligands.

Organic silver coating agents are described in PCT Publication No. WO 94/16047 and co-pending European Application No. EP-A-690122. Nitrogen-containing corrosion inhibitor compounds are described in co-pending European Application No. EP-A-634478. Mn(II) compounds for use in corrosion inhibition are described in co-pending European Application No. EP-A-672749.

The organic silver coating agent may be incorporated in a proportion of 0.05 to 10%, preferably 0.1 to 5%, based on the weight of the total composition.

The functional role of the silver coating agent is to form "in use" a protective coating layer on any silverware components of the wash load to which the compositions of the invention are applied. The silver coating agent should thus have a high affinity for adhesion to solid silver surfaces, particularly when present as a component of an aqueous detergent and bleach solution with which the solid silver surfaces are treated.

Organic silver coating agents suitable for use herein include fatty esters of mono- or polyhydric alcohols having 1 to 40 carbon atoms in the hydrocarbon chain.

The fatty acid portion of the fatty acid ester can be obtained from mono- or polycarboxylic acids having 1 to 40 carbon atoms in the hydrocarbon chain. Suitable examples of monocarboxylic fatty acids include behenic acid, stearic acid, oleic acid, palmitic acid, myristic acid, lauric acid, acetic acid, propionic acid, butyric acid, isobutyric acid, valeric acid, lactic acid, glycolic acid and β,β'-dihydroxyisobutyric acid. Examples of suitable polycarboxylic acids include n-butylmalonic acid, isocitric acid, citric acid, maleic acid, malic acid and succinic acid.

The fatty alcohol residue in the fatty acid ester can be represented by mono- or polyhydric alcohols having 1 to 40 carbon atoms in the hydrocarbon chain. Examples of suitable fatty alcohols include behenyl, arachidyl, cocoyl, oleyl and lauryl alcohol, ethylene glycol, glycerol, ethanol, isopropanol, vinyl alcohol, diglycerol, xylitol, sucrose, erythritol, pentaerythritol, sorbitol or sorbitan.

Preferably, the fatty acid and/or fatty alcohol groups of the fatty acid ester additive material have 1 to 24 carbon atoms in the alkyl chain.

Preferred fatty acid esters herein are ethylene glycol, glycerol and sorbitan esters, wherein the fatty acid portion of the ester normally comprises a species selected from behenic acid, stearic acid, oleic acid, palmitic acid or myristic acid.

The glycerol esters are also highly preferred. These are mono-, di- or triesters of glycerol and the fatty acids as defined above.

Specific examples of fatty alcohol esters for use herein include: stearyl acetate, palmityl dilactate, cocoyl isobutyrate, oleyl maleate, oleyl dimaleate and talloyl propionate. Fatty acid esters suitable herein include: xylitol monopalmitate, pentaerythritol monostearate, sucrose monostearate, glycerol monostearate, ethylene glycol monostearate. Sorbitan esters. Suitable sorbitan esters include sorbitan monostearate, sorbitan palmitate, sorbitan monolaurate, sorbitan monomyristate, sorbitan monobehenate, sorbitan monooleate, sorbitan dilaurate, sorbitan distearate, sorbitan dibehenate, sorbitan dioleate and mixed tallow alkyl sorbitan mono- and diesters.

Glycerol monostearate, glycerol monooleate, glycerol monopalmitate, glycerol monobehenate and glycerol distearate are preferred glycerol esters herein.

Suitable organic silver coating agents include triglycerides. Mono- or diglycerides and fully or partially hydrogenated derivatives thereof, and any mixtures thereof. Suitable sources of fatty acid esters include vegetable and fish oils and animal oils. Suitable vegetable oils include soybean oil, cottonseed oil, castor oil, olive oil, peanut oil, safflower oil, sunflower oil, rapeseed oil, grapeseed oil, palm oil, and corn oil.

Waxes, including microcrystalline waxes, are suitable organic silver coating agents herein. Preferred waxes have a melting point in the range of 35°C to 110°C and generally contain from 12 to 70 carbon atoms. Preferred are petroleum waxes of the paraffin and microcrystalline type, which are composed of long-chain saturated carbon compounds.

Alginates and gelatine are suitable organic silver coating agents.

Dialkylamine oxides such as C₁₂-C₂₀ methylamine oxide and dialkyl quaternary ammonium compounds and salts such as the C₁₂-C₂₀ methylammonium halides are also suitable.

Other suitable organic silver coating agents include certain polymeric materials. Polyvinylpyrrolidones having an average molecular weight from 12,000 to 700,000, polyethylene glycols (PEG) with an average molecular weight of 600 to 10,000, polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, and cellulose derivatives such as methylcellulose, carboxymethylcellulose and hydroxyethylcellulose are examples of such polymeric materials.

Certain perfume materials, particularly those which exhibit high substantivity for metallic surfaces, are also suitable as organic silver coating agents herein.

Polymeric soil repellents can also be used as organic silver coating agents.

A preferred organic silver coating agent is a paraffin oil, typically a predominantly branched aliphatic hydrocarbon having a carbon atom number in the range of 20 to 50; preferably paraffin oil selected from predominantly branched C₂₅₋₄₅ species having a ratio of cyclic to non-cyclic hydrocarbons of 1:10 to 2:1, preferably 1:5 to 1:1. A paraffin oil satisfying these characteristics having a ratio of cyclic to non-cyclic hydrocarbons of 32:68 is sold by Wintershall, Salzbergen, Germany, under the trade designation WINOG 70.

Nitrogen-containing corrosion inhibitor compounds

Suitable nitrogen-containing corrosion inhibitor compounds include imidazole and derivatives thereof such as benzimidazole, 2-heptadecylimidazole and those imidazole derivatives described in Czech Patent No. 139,279 and British Patent GB-A-1,137,741, which also discloses a process for preparing imidazole compounds.

Also suitable as nitrogen-containing corrosion inhibitor compounds are pyrazole compounds and their derivatives, particularly those in which the pyrazole is substituted at any of the 1-, 3-, 4- or 5-positions by substituents R₁, R₃, R₄ and R₅, wherein R₁ is any of H, CH₂OH, CONH₃ COCH₃, R₃ and R₅ are any of C₂₀ alkyl or hydroxyl, and R₄ is any of H, NH₂ or NO₂.

Other suitable nitrogen-containing corrosion inhibitor compounds include benzotriazole, 2-mercaptobenzothiazole, 1-phenyl-5-mercapto- 1,2,3,4-tetrazole, thionalide, morpholine, melamine, distearylamine, stearoylstearamide, cyanuric acid, aminotriazole, aminotetrazole and indazole.

Nitrogen-containing compounds such as amines, especially distearylamine and ammonium compounds such as ammonium chloride, ammonium bromide, ammonium sulfate or diammonium hydrogen citrate are also suitable.

Mn(II) corrosion inhibitor compounds

The detergent tablets may contain a Mn(II) corrosion inhibitor compound. The Mn(II) compound is preferably incorporated at a level of from 0.005 to 5%, more preferably from 0.01 to 1%, most preferably from 0.02 to 0.4% by weight of the compositions. Preferably the Mn(II) compound is incorporated at a level to provide from 0.1 ppm to 250 ppm, more preferably from 0.5 ppm to 50 ppm, most preferably from 1 ppm to 20 ppm, by weight of Mn(II) ions in any bleaching solution.

The Mn(II) compound may be an inorganic salt in anhydrous or any hydrated forms. Suitable salts include manganese sulfate, manganese carbonate, manganese phosphate, manganese nitrate, manganese acetate and manganese chloride. The Mn(II) compound may be a salt or complex of an organic fatty acid such as manganese acetate or manganese stearate.

The Mn(II) compound may be a salt or complex of an organic ligand. In a preferred aspect, the organic ligand is a heavy metal ion complexing agent. In another preferred aspect, the organic ligand is a crystal growth inhibitor.

Other corrosion inhibitor compounds

Other suitable additional corrosion inhibitor compounds include mercaptans and diols, especially mercaptans with 4 to 20 carbon atoms, including lauryl mercaptan, thiophenol, thionaphthol, thionalide and thioanthranol. Also suitable are saturated or unsaturated C₁₀₋₂₀ fatty acids or their salts, especially aluminum tristearate. The C₁₂₋₂₀ hydroxy fatty acids or their salts are also suitable. Phosphonated octadecane and other antioxidants such as beta-hydroxytoluene (BHT) are also suitable.

Copolymers of butadiene and maleic acid, particularly those sold under trade reference number 07787 by Polysciences, Inc., have been found to be of particular utility as corrosion inhibitor compounds.

Hydrocarbon oils

Another preferred detergent component for use in the present invention is a hydrocarbon oil, typically predominantly long chain aliphatic hydrocarbons having a carbon atom number in the range of 20 to 50; preferred hydrocarbons are saturated and/or branched; preferred hydrocarbon oils are selected from predominantly branched C25-45 species having a ratio of cyclic to non-cyclic hydrocarbons of 1:10 to 2:1, preferably 1:5 to 1:1. A preferred hydrocarbon oil is paraffin. A paraffin oil satisfying the characteristics described above having a ratio of cyclic to non-cyclic hydrocarbons of 32 : 68, is sold by Wintershall, Salzbergen, Germany, under the trade name WINOG 70.

Water-soluble bismuth compound

The detergent tablets of the invention which are suitable for use in dishwashing processes may contain a water-soluble bismuth compound which is preferably present in a proportion of 0.005 to 20%, more preferably 0.01 to 5%, most preferably 0.1 to 1% by weight of the compositions.

The water-soluble bismuth compound can be essentially any salt or complex of bismuth with essentially any inorganic or organic counter anion. Preferred inorganic bismuth salts are selected from bismuth trihalides, bismuth nitrate and bismuth phosphate. Bismuth acetate and citrate are preferred salts with an organic counter anion.

Enzyme stabilization system

Enzyme-containing compositions preferred herein may contain from 0.001 to 10%, preferably from 0.005 to 8%, most preferably from 0.01 to 6%, by weight of an enzyme stabilizing system. The enzyme stabilizing system may be any stabilizing system that is compatible with the detersive enzyme. Such stabilizing systems may be calcium ions, boric acid, propylene glycol, short chain carboxylic acid, boronic acid, chlorine bleach scavengers, and mixtures thereof. Such stabilizing systems may also include reversible enzyme inhibitors, such as reversible protease inhibitors.

Lime soap-dispersant compound

The tablets according to the invention may contain a lime soap dispersant compound, which is preferably present in a proportion of 0.1 to 40% by weight, more preferably 1 to 20% by weight, most preferably 2 to 10% by weight, of the compositions.

A lime soap dispersant is a material which prevents the precipitation of alkali metal, ammonium or amine salts of fatty acids by calcium or magnesium ions. Preferred lime soap dispersant compounds are described in PCT Application No. WO 93/08877.

Foam suppression system

The detergent tablets of the invention, when formulated for use in machine washing compositions, preferably comprise a suds suppression system present at a level of from 0.01 to 15%, preferably from 0.05 to 10%, most preferably from 0.1 to 5% by weight of the composition.

Suitable foam suppression systems for use herein can comprise essentially any known antifoam compounds including, for example, silicone antifoam compounds, 2-alkyl and alkanol antifoam compounds. Preferred foam suppression systems and antifoam compounds are described in PCT Application No. WO 93/08876 and EP-A-705324.

Dye transfer inhibiting polymeric agents

The washing or cleaning agent tablets described herein may also contain 0.01 to 10%, preferably 0.05 to 0.5% by weight of polymeric dye transfer inhibiting agents.

The polymeric dye transfer inhibiting agents are preferably selected from polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, polyvinylpyrrolidone polymers or combinations thereof.

Other optional components

Other optional ingredients suitable for inclusion in the compositions of the invention include perfumes and filler salts, with sodium sulfate being a preferred filler salt.

pH of the compositions

The detergent tablets according to the invention are preferably not formulated to have an excessively high pH, preferably a pH, measured as a 1% solution in distilled water, of 8.0 to 12.5, more preferably 9.0 to 11.8, most preferably 9.5 to 11.5.

Machine dishwashing process

Any suitable method for machine washing or cleaning of soiled tableware will be considered.

A preferred machine dishwashing process comprises the treatment of soiled objects selected from crockery, glassware, silverware, metallic objects, cutlery and mixtures thereof, with an aqueous liquid having dissolved or dispersed therein an effective amount of a detergent tablet according to the invention. By effective amount of detergent tablet is meant 8 g to 60 g of the product dissolved or dispersed in a washing solution of a volume of 3 to 10 liters, which are typical product dosages and washing solution volumes which are usually used in conventional machine dishwashing processes. Preferably the detergent tablets have a weight of 15 g to 40 g, more preferably 20 g to 35 g.

Examples Abbreviations used in the examples

In the detergent or cleaning agent compositions, the abbreviated component identifications have the following meanings:

STPP : Sodium tripolyphosphate

Bicarbonate: Sodium bicarbonate

Citric acid : anhydrous citric acid

Carbonate : anhydrous sodium carbonate

Silicate: amorphous sodium silicate (SiO2:Na2O ratio = 2.0)

SKS-6 : crystalline layered silicate of the formula b-Na₂Si₂O�5;

PB1: anhydrous sodium perborate monohydrate

non-ionic component: mixed ethoxylated/propoxylated C₁₃-C₁₅ fatty alcohol with an average degree of ethoxylation of 3.8 and an average degree of propoxylation of 4.5, sold under the trade name Plurafac by BASF

TAED: Tetraacetylethylenediamine

HEDP : ethane-1-hydroxy-1,1-diphosphonic acid

PAAC: Pentaamine acetate cobalt(III) salt

Paraffin: Paraffin oil, sold under the trade name Winog 70 by Wintershall

Protease : proteolytic enzyme

Amylase: amylolytic enzyme

BTA : Benzotriazol

Sulfate : anhydrous sodium sulfate

PEG 3000 : Polyethylene glycol with a molecular weight of about 3000, available from Hoechst

PEG 6000 : Polyethylene glycol with a molecular weight of about 6000, available from Hoechst

pH : measured as a 1% solution in distilled water at 20ºC

In the following examples, all parts are given as parts by weight:

Examples I-VI

The following illustrates examples of detergent tablets according to the invention which are suitable for use in a dishwasher.

The multiphase tablet compositions are prepared as follows. The Phase 1 detergent active composition is prepared by mixing the granular and liquid components and is then introduced into the die of a conventional rotary press. The press includes a punch suitably shaped to form the die. The cross-section of the die is about 30 x 38 mm. The composition is then subjected to a compression force of 92.12 MPa (940 kg/cm2) and the punch is then raised to expose the first phase of the tablet which contains the die in its upper surface. The Phase 2 detergent active composition is prepared in a similar manner and introduced into the die. The particulate active composition is then subjected to a compression force of 16.66 MPa (170 kg/cm2), the punch is raised and the multiphase tablet is ejected from the tablet press. The resulting tablet dissolves or disintegrates in a washing machine as described above within 12 minutes, with Phase 2 of the tablets dissolving within 5 minutes. The tablets provide excellent dissolution and cleaning characteristics, along with good tablet integrity and strength.

Claims (25)

1. Multiphase detergent tablet for machine dishwashing, weighing from 15 g to 40 g, comprising a) a first phase in the form of a compressed shaped body with at least one cavity in its surface; and b) a second phase in the form of a compressed body which is adherently contained within the hollow mold and which is formed of particulate solid and has a mass of less than 4 g, wherein the tablet composition comprises one or more detergent actives selected from builders, colorants, surfactants and enzymes which are predominantly concentrated in the second phase, and wherein the second phase additionally comprises a binder and wherein the tablet is designed so that differential dissolution of the phases occurs during use. 2. A multiphase detergent tablet according to claim 1, wherein the first phase is prepared at a compression pressure of at least 350 kg/cm² and wherein the second phase is compressed at the pressure of less than 350 kg/cm². 3. Multiphase detergent tablet according to claim 1 or claim 2, wherein the binder is selected from the group consisting of sugar and sugar derivatives, starch and starch derivatives, inorganic and organic polymers. 4. A multiphase detergent tablet according to any one of the preceding claims, additionally comprising a barrier layer between the first and second phases. 5. Multiphase detergent tablet according to claim 4, wherein the barrier layer comprises a binder applied in liquid form. 6. A multiphase detergent tablet according to claim 4, wherein the barrier layer comprises a binder selected from the group consisting of sugar and sugar derivatives, starch and starch derivatives, and inorganic and organic polymers. 7. Multiphase detergent tablet according to at least one of the preceding claims, wherein the times in which the first and second phases dissolve in a dishwasher are independent of one another. 8. Multiphase detergent tablet according to at least one of the preceding claims, wherein the first and second phases are present in a weight ratio of at least 6:1, preferably at least 10:1. 9. Multiphase detergent tablet according to at least one of the preceding claims, wherein the second phase dissolves faster than the first phase. 10. Multiphase detergent tablet according to at least one of the preceding claims, wherein the compression pressures applied to the first and second phases are in a ratio of at least 2:1. 11. Multiphase detergent tablet according to at least one of the preceding claims, wherein the second phase is formulated such that at least 50, preferably 60, more preferably at least 80% by weight of the one or more detergent active ingredients are released to the wash liquor within 10 minutes, preferably within 5 minutes and more preferably within 3 minutes, determined according to DIN 44990 using a Bosch dishwasher in the 65ºC normal wash program with a water hardness at 18ºH using a minimum of six repetitions. 12. Multiphase detergent tablet according to at least one of the preceding claims, wherein the one or more detergent active ingredients is an enzyme selected from protease, amylase, peroxidases, cutinase and cellulase. 13. A multi-phase detergent tablet according to claim 1, wherein the second phase dissolves after the first phase, thereby providing cleaning or rinsing benefits towards the end of the wash cycle. 14. Multiphase detergent tablet according to at least one of the preceding claims, wherein the one or more detergent active ingredients is a low-foaming nonionic surfactant. 15. Multiphase detergent tablet according to claim 1, wherein the detergent active ingredient is selected from colorants and enzymes. 16. Multiphase detergent tablet according to at least one of the preceding claims, wherein the hollow shape has an inwardly directed concave surface. 17. Multiphase detergent tablet according to at least one of the preceding claims, wherein the second phase has a mass of 0.1 to 2.5 g. 18. A method of machine dishwashing, comprising loading a dishwasher with one or more multiphase detergent tablets, the or each tablet having a weight of 15 g to 40 g and comprising: a) a first phase in the form of a compressed shaped body with at least one cavity in its surface; and b) a second phase in the form of a compressed body which is adherently contained within the hollow mold and which is formed of particulate solid and has a mass of less than 4 g, wherein the tablet composition comprises one or more detergent actives selected from builders, colorants, surfactants and enzymes which are predominantly concentrated in the second phase, and wherein the second phase additionally comprises a binder and wherein the tablet is designed so that differential dissolution of the phases occurs. 19. A method according to claim 18, wherein the multiphase detergent tablet dissolves or disintegrates in less than 15 minutes in the dishwasher, determined according to DIN 44990 using a Bosch dishwasher at 65ºC normal wash program with water hardness at 18ºH using a minimum of six repetitions. 20. A method according to claim 18 or claim 19, wherein the second phase dissolves faster than the first phase. 21. A method according to any one of claims 18 to 20, wherein the second phase dissolves within the dishwasher in less than 5 minutes, determined according to DIN 44990 using a Bosch dishwasher at 65ºC normal wash program with water hardness at 18ºH using a minimum of six repetitions. 22. A method according to at least one of claims 18 to 21, wherein the first phase dissolves in the dishwasher within 10 to 15 minutes, determined according to DIN 44990 using a Bosch dishwasher at 65ºC normal wash program with water hardness at 18ºH using a minimum of six repetitions. 23. A process according to at least one of claims 18 to 22, wherein the second phase is formulated such that at least 50, preferably 60, further preferably at least 80% by weight of the one or more detergent active ingredients are released into the wash liquor within 10 minutes, preferably within 5 minutes and more preferably within 3 minutes, determined according to DIN 44990 using a Bosch dishwasher in the 65ºC normal wash program with a water hardness of 18ºH using a minimum of six repetitions. 24. A method according to any one of claims 18 to 23, which is a method for washing soiled objects, selected from tableware, glassware, silverware, metallic objects, cutlery and mixtures thereof. 25. A method according to any one of claims 18 to 24, wherein the tablet has any of the additional features recited in claims 2 to 8, 10, 12 and 14-17.