EP0743978B1 - Bleaching tablet with builder substances - Google Patents

Abstract

Tablets contg. builder substances comprise 2-100 wt.% amorphous, partly crystalline and/or crystalline layered silicates of formula Na2SixO2x+1.yH2O (I), where x=1.9-4 and y=0-20. The water content of the tablets is no more than the maximum theoretical water-binding capacity of the tablet ingredients. Also claimed are: (1) a process for producing tablets as above where the premixes intended for pressing are prepd. by mixing the individual ingredients, at least some of which are pregranulated; (2) a wash process in which at least two tablets as above, with the same or different compsn., are used in a single wash cycle, pref. a base detergent tablet and a water-softening and/or bleaching tablet; and (3) a wash process in which at least one tablet as above is used in a single wash cycle, the tablet(s) being dispensed onto the wash in the washing machine right at the start of the wash cycle. Pref. detergent tablets comprise 5-60 (esp. 10-40)wt.% (I), 0.5-98 wt.% zeolite and/or phosphate (pref. less than 30 wt.% phosphate), up to 40 wt.% anionic surfactants and/or soaps, and up to 20 wt.% nonionic surfactants. Water-softening tablets comprise 20-80 (esp. 30-60)wt.% (I), 0-80 (esp. 10-60)wt.% zeolite and/or phosphate, 0-50 (esp. 2-20) wt.% polycarboxylate, 0-15 (esp. 1-10)wt.% polymeric polycarboxylate, and 0-30 (esp. 2-15)wt.% surfactants and salts. Bleaching tablets comprise 20-80 (esp. 30-60) wt.% (I) and 20-50 (esp. 25-45) wt.% peroxy bleach. (I) may be used together with amorphous silicates of water-glass type.

Description

The invention relates to bleaching tablets, preferably washing or cleaning active Tablets, in particular detergent tablets or compounds in tablet form for Detergents that contain silicate builder substances.

Tablets have a number of advantages over powdered agents, such as simple dosing and low packaging volume requirements. Problems arise, however, in that relatively high compression pressures have to be used to achieve adequate dimensional stability and fracture resistance when pressing the powdery components. Because of the high degree of compaction, such tablets often have inadequate disintegration and dissolving properties when used. Additional difficulties arise from the use of nonionic surfactants. According to the teaching of international patent application WO-A-90/02165, these problems can be solved by producing at least two granular components before pressing, the total amount of the anionic surfactants in one component and the main amount of the nonionic surfactants in the other component are included. The anionic surfactant-containing component preferably contains up to 20% by weight of anionic surfactants including the soaps, up to 30% by weight of water-containing zeolite, inorganic salts such as amorphous silicates and carbonates up to 40% by weight, polycarboxylates up to 5% by weight. , Sulfate up to 20 wt .-% and water, which is not bound to the zeolite, to a maximum of 5 wt .-%. The last three statements apply equally to the second component, which also preferably contains up to 15% by weight of nonionic surfactants, up to 20% by weight of water-containing zeolite and up to 10% by weight of soda. Other components, which contain bleaching agents and / or enzymes, for example, are also optionally available.

Tablets containing builder substances and layered sodium silicates are disclosed in European patent application EP 508 934 . This document does not describe zeolite-free bleaching tablets.

Detergents which can be compressed into tablets are disclosed in European patent application EP 504 091 . Bleaching tablets, the bulk of which is based on silicate, are neither disclosed nor suggested in this document.

Crystalline layered sodium silicates of the formula NaMSi _x O _{2x + 1} .yH ₂ O, where M is sodium or hydrogen, x is a number from 1.9 to 4 and y is a number from 0 to 20 and preferred values for x 2, 3 or 4, can substitute phosphates and zeolites. Such crystalline layered silicates are described, for example, in European patent application EP-A-0 164 514 . Preferred crystalline layered silicates are those in which M is sodium and x is 2 or 3. In particular, both β- and δ-sodium disilicate Na ₂ Si ₂ O ₅ .yH ₂ O are preferred, wherein β-sodium disilicate can be obtained, for example, by the method described in international patent application WO-A-91/08171 . β-sodium disilicate is commercially available under the name SKS 7®, δ-sodium disilicate is available under the name SKS 6® (commercial products from Hoechst AG, Federal Republic of Germany). These powders generally have a bulk density of less than 600 g / l and have high fines content, usually more than 30% by weight, with a particle size below 0.1 mm. Since crystalline layered silicates suffer from losses in their action as builders in spray drying detergent-containing slurries, caused by the partial destruction of their crystalline structure, they should preferably be incorporated into detergents or cleaning agents by other process methods. However, due to their high proportion of fine grains and thus their dusty structure, these powders are also unsuitable for use as an admixing component with other granular components of detergents or cleaning agents. When granulating crystalline layered sodium silicates, it should be noted that the strong abrasive properties of these silicates can damage the apparatus. This means on the one hand that the process safety is endangered and additional checks of the mixing and granulating tools are required, but also that the silicate product can be contaminated with traces of metal, in particular traces of heavy metals, due to the material abrasion. For ecological reasons, it is desirable to keep the contamination of the end product as low as possible. It is also known to the person skilled in the art that, for example, the stability of peroxy bleaching agents is adversely affected by heavy metals.

Amorphous alkali metal silicates, in particular those with a molar M ₂ O: SiO ₂ ratio of 1: 1.9 to 1: 4.0, where M preferably represents sodium and / or potassium, can generally be spray-dried, but white the expert that the spray drying of slurries which also contain zeolite in addition to the amorphous silicates leads to negative interactions, as a result of which the exchange capacity of the zeolite is reduced and deposits which are difficult to remove can be deposited on the laundry. Granules which have a high proportion of amorphous silicates or pure spray-dried or granulated amorphous silicates, on the other hand, are hygroscopic, so that they have to be specially protected against the ingress of atmospheric moisture during storage.

On the one hand, there was the task of offering an advantageous form of offer for products develop which contain amorphous and / or crystalline silicates and bleaches. there should both the procedural security and the stability of the other, if applicable Components, especially the bleach, the offer form are increased. A Another object of the invention was to contain builder substance and bleach Offer forms that are sufficiently soluble or are dispersible.

This object was achieved in that an offer form with a relatively small specific surface was chosen, which can be produced with little water.

a) 20 bis 80 Gew.-%, vorzugsweise 30 bis 60 Gew.-% amorphe, teilkristalline und/oder kristalline schichtförmige Natriumsilikate der Formel Na₂Si_xO_2x+1·yH₂O, worin x eine Zahl von 1,9 bis 4 und y eine Zahl von 0 bis 20 ist und bevorzugte Werte für x 2, 3 oder 4 sind,

b) 20 bis 50 Gew.-%, vorzugsweise 25 bis 45 Gew.-% Peroxy-Bleichmittel,

aber keinen Zeolith enthält, mit der Maßgabe, daß die Tablette Wasser nur in den Mengen enthält, daß das maximale theoretische Wasserbindevermögen der Inhaltsstoffe nicht überschritten wird.The invention accordingly relates to a bleaching tablet containing builder substances, the tablet

a) 20 to 80 wt .-%, preferably 30 to 60 wt .-% amorphous, partially crystalline and / or crystalline layered sodium silicates of the formula Na ₂ Si _x O _{2x + 1} · yH ₂ O, where x is a number of 1.9 to 4 and y is a number from 0 to 20 and preferred values for x are 2, 3 or 4,

b) 20 to 50% by weight, preferably 25 to 45% by weight, of peroxy bleach,

but contains no zeolite, with the proviso that the tablet contains water only in the amounts that the maximum theoretical water-binding capacity of the ingredients is not exceeded.

The maximum theoretical water binding capacity can be based on the one described below Be determined. Some components of the tablets form an accepted one Storage temperature of 15 to 45 ° C stable hydrates. This applies e.g. for zeolite. In contrast, components such as sodium sulfate and polymeric polycarboxylates are considered anhydrous substances, although it is known that these are in granules in the Usually available in hydrated form. Also crystalline layered sodium disilicates are calculated anhydrous, while amorphous sodium silicates, for example May have water content up to about 22 wt .-%. The sum of the crystal water shares from the stable hydrates gives the maximum theoretical water content the tablet of the invention. It may even be preferred that the tablet in over-dried form, i.e. contains less water than the maximum corresponds to theoretical water binding capacity or as of the tablet ingredients can be recorded stably.

The tablets can be produced in such a way that the amorphous, partially crystalline and / or crystalline layered sodium silicates and, if appropriate, all other constituents are mixed with one another in a mixer and the mixture by means of conventional tablet presses, for example eccentric presses, hydraulic presses or rotary presses with pressing pressures in the range of 10 ⁵ to 3 · 10 ⁷ Pa (1 to 300 bar), advantageously in the range from about 5 · 10 ⁵ to 2 · 10 ⁷ Pa (5 to 200 bar) and in particular between 10 ⁶ to 1.5 · 10 ⁷ Pa (10 and 150 bar) pressed. The compression is preferably carried out without the addition of water. In a preferred embodiment of the invention, however, the premixes intended for compression are produced by mixing the individual ingredients, which are present at least in part in pre-assembled form as a granular compound. These include, for example, roll-compacted, crystalline, layered or amorphous sodium disilicates, which have optionally been impregnated with liquid to waxy components, for example nonionic surfactants. In particular, this enables water-free pre-assembly, which is particularly advantageous. In this way, break-resistant tablets with good breaking strength, which dissolve sufficiently quickly under application conditions, are obtained without any problems. The pressing conditions in the respective case are usually to be optimized for the setting of the desired solubility of the tablet while at the same time having sufficient strength or hardness of the tablet. It applies in a manner known per se that higher compression pressures reduce the solubility of the tablet. Preferred tablets have a breaking strength of at least 55 N and in particular at least 60 N. Tablets with breaking strengths above 150 N are also possible.

Practically all sensible, manageable design forms come in as the spatial form Consider as long as they meet the requirements that the contact to Tableting equipment is relatively small during the manufacturing process. Are preferred here cylindrical configurations with an oval or circular cross section Art specified below. A tablet produced in this way preferably has a weight from 10 to 120 g, in particular from 20 to 100 g, the diameter of the tablets is usually less than 100 mm. Preferred detergent tablets have one Diameter of up to 80 mm and in particular from 30 to 80 mm. However, it is also possible and particularly preferred with regard to improved solubilities, several, i.e. at least 2 tablets with the same or different Use composition. These tablets preferably have a weight of 10 to 40 g, with diameters of 20 to 50 mm being preferred. The diameter / height ratio the tablets should be optimized so that the lowest possible Abrasion on the vertical walls of the tabletting apparatus (high diameter / small Height) with sufficient stability and a surface that is not too large (smaller Diameter / high height) is guaranteed. Preferred diameter / height ratios the cylindrical compacts are about 0.5: 1 to 10: 1, in particular 1: 1 to 8: 1.

The content of the tablets in amorphous, semi-crystalline and / or crystalline layered sodium silicates can vary within a wide range. Which Quantity ranges now actually used depend on the area of application in who should use this tablet. In the bleaching according to the invention Tablets that can be added to a wash liquor as bleach boosters, the contents are amorphous, partially crystalline and / or crystalline layered Sodium silicates at 20 to 80 wt .-% and in particular at 30 to 60 wt .-%.

Of the crystalline layered sodium silicates, the low-water to anhydrous disilicates are particularly preferred. The preferred amorphous silicates primarily include the known spray-dried water glasses with a Na ₂ O: SiO ₂ weight ratio of 1: 1.9 to 1: 3.35. A preferred embodiment of silicates are silicate-carbonate compounds, for example those according to European patent applications EP-A-0 488 868 and EP-A-0 561 565. Such compounds are sold under the name Nabion 15® (commercial product from Rôhne- Poulenc) commercially available. A particularly preferred embodiment of silicates is, however, those X-ray amorphous silicates as described in the older German patent application DE 44 00 024 . Therefore, tablets are preferred which contain either crystalline layered sodium silicates of the specified type or such X-ray amorphous silicates, or tablets which contain crystalline layered sodium silicates and X-ray amorphous silicates in a weight ratio of 10: 1 to 1:10. Particularly preferred tablets are free of conventional amorphous silicates of the water glass type or contain these amorphous silicates of the water glass type only in combination with crystalline layered sodium silicates and / or X-ray amorphous silicates, the content of amorphous silicates of the water glass type advantageously being 20% by weight. -% and in particular 15 wt .-%, each based on the total amount of silicates present in the tablet, does not exceed.

The tablets can contain up to 60% by weight of other ingredients of washing or Contain detergents. It is particularly preferred that the tablets Have usual tabletting aids and disintegrants.

Auxiliaries which disintegrate or dissolve are regarded as disintegrants influence positively in the aqueous application phase. These explosives can be inorganic and / or organic in nature. Typical inorganic explosives The basis is, for example, swellable layered silicates such as bentonites. Organic Disintegrants can be natural substances or their derivatives based on starch or Be cellulose. For example, cross-linked potato starch, microcrystalline Cellulose powder, but especially also common ingredients of washing or Cleaning agents such as the salts of polymeric polyacrylates or polymethacrylates, for example those with a low molecular weight between 1000 and 5000, but also methyl celluloses and / or hydroxypropyl celluloses or Methyl hydroxypropyl celluloses can be called.

Other examples are acetates or percarbonates. The latter are preferably in tablets containing bleach or used directly in the bleaching tablets. It is usual, such disintegrants in amounts of up to about 15% by weight, based on the tablet, to use. Due to the use of water-soluble silicates, it is sufficient for the Tablets according to the invention in most cases, the disintegrants in amounts of far below 10% by weight, preferably in amounts of up to 5% by weight and in particular still use below. When using poly (meth) acrylates and / or non-ionic Cellulose ethers generally lead to very good amounts of around 1% by weight Results.

In contrast to the explosives, tableting aids provide a better one Cohesion of the individual powdery or granular components and wear thus contributing to the stability of the tablet. However, there are a number of explosives which also serve as tableting aids or binders. These include for example starch, starch and cellulose derivatives, but also gelatin and polyvinyl pyrrolidone. Other preferred binders are, for example, the Processing temperature liquid to pasty nonionic surfactants.

The explosives and tableting aids are preferably in dry form or in a used in nonionic surfactant or suspended form. An aqueous form of use is less preferred because water is only available in quantities during the process may be admitted that the maximum theoretical water binding capacity of the Tablet ingredients are not exceeded. In a particularly preferred Embodiment of the invention is therefore not an ingredient in the form of an aqueous Solution or suspension used and the pressing without adding water carried out.

In a preferred embodiment of the invention, the tablets contain especially other common builder substances. These include inorganic ones Builder substances such as phosphates or organic builder substances such as polycarboxylates and / or polymeric polycarboxylates.

Tablets which contain phosphates are preferred, the content of phosphates preferably limited to a maximum of 50% by weight and in particular to a maximum of 30% by weight is. The bleaching tablets according to the invention are free of zeolite in order to be negative Exclude interactions.

In a further preferred embodiment of the invention, the tablets contain 0.5 to 50% by weight of organic builder substances such as polycarboxylates and / or polymeric polycarboxylates, but also their acids. The polycarboxylic acids or the polycarboxylates include, in particular, the polycarboxylic acids used in the form of their sodium salts, such as citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids and mixtures of these. Suitable polymeric polycarboxylates are, for example, the sodium salts of polyacrylic acid or polymethacrylic acid, for example those with a relative molecular weight of 800 to 150,000 (based on acid). Suitable copolymeric polycarboxylates are, in particular, those of acrylic acid with methacrylic acid and of acrylic acid or methacrylic acid with maleic acid. Copolymers of acrylic acid with maleic acid which contain 50 to 90% by weight of acrylic acid and 50 to 10% by weight of maleic acid have proven to be particularly suitable. Their relative molecular weight, based on free acids, is generally 5,000 to 200,000, preferably 10,000 to 120,000 and in particular 50,000 to 100,000. Terpolymeric polycarboxylates are also particularly preferred, for example those which, as monomers, contain salts of acrylic acid and maleic acid, and also vinyl alcohol or vinyl alcohol Derivatives ( DE 43 00 772 ) or the salts of acrylic acid and 2-alkylallylsulfonic acid as monomers and sugar derivatives ( DE 42 21 381 ).

The (co) polymeric polycarboxylates are preferably used either as a powder or as granular compound used. Suitable granular compounds are, for example those known from international patent application WO-A-92/13937.

Further suitable builder systems are oxidation products of carboxyl group-containing polyglucosans and / or their water-soluble salts, as are described, for example, in international patent application WO-A-93/08251 or their production, for example, in international patent application WO-A-93/16110 or the older German one Patent application DE 43 30 393 is described.

Other suitable builder substances are polyacetals, which can be obtained by reacting dialdehydes with polyolcarboxylic acids which have 5 to 7 carbon atoms and at least 3 hydroxyl groups, for example as described in European patent application EP-A-0 280 223 . Preferred polyacetals are obtained from dialdehydes such as glyoxal, glutaraldehyde, terephthalaldehyde and their mixtures and from polyol carboxylic acids such as gluconic acid and / or glucoheptonic acid.

In a further preferred embodiment of the invention, the tablets have up to 40% by weight of anionic surfactants and / or soaps. As anionic surfactants for example, those of the sulfonate and sulfate type are used.

Preferred surfactants of the sulfonate type are C ₉ -C ₁₃ alkylbenzenesulfonates, olefin sulfonates, ie mixtures of alkene and hydroxyalkanesulfonates, and also disulfonates such as are obtained, for example, from C ₁₂ -C ₁₈ monoolefins with a terminal or internal double bond by sulfonating with gaseous Sulfur trioxide and subsequent alkaline or acidic hydrolysis of the sulfonation products is considered.

Also suitable are alkanesulfonates obtained from C ₁₂ -C ₁₈ alkanes, for example by sulfochlorination or sulfoxidation with subsequent hydrolysis or neutralization.

Also suitable are the esters of α-sulfo fatty acids (ester sulfonates), e.g. the α-sulfonated Methyl ester of hydrogenated coconut, palm kernel or tallow fatty acids.

Other suitable anionic surfactants are sulfonated fatty acid glycerol esters. Fatty acid glycerol esters are to be understood as meaning the mono-, di- and triesters and their mixtures as obtained in the production by esterification by a monoglycerol with 1 to 3 moles of fatty acid or in the transesterification of triglycerides with 0.3 to 2 moles of glycerol. Preferred sulfated fatty acid glycerol esters are the sulfonation products of saturated fatty acids having 6 to 22 carbon atoms, for example caproic acid, caprylic acid, capric acid, myristic acid, lauric acid, palmitic acid, stearic acid or behenic acid. If one starts from fats and oils, that is to say natural mixtures of different fatty acid glycerol esters, it is necessary to largely saturate the starting products with hydrogen in a manner known per se, ie to harden them to iodine numbers less than 5, advantageously less than 2. Typical examples of suitable feedstocks are palm oil, palm kernel oil, palm stearin, olive oil, turnip oil, coriander oil, sunflower oil, cottonseed oil, peanut oil, linseed oil, lard oil or lard. Due to their high natural content of saturated fatty acids, it has proven to be particularly advantageous to start from coconut oil, palm kernel oil or beef tallow. The sulfonation of the saturated fatty acids with 6 to 22 carbon atoms or the mixtures of fatty acid glycerol esters with iodine numbers less than 5, which contain fatty acids with 6 to 22 carbon atoms, is preferably carried out by reaction with gaseous sulfur trioxide and subsequent neutralization with aqueous bases, as described in the international patent application WO -A-91/09009 .

Preferred alk (en) yl sulfates are the sulfuric acid half-esters of the C ₁₂ -C ₁₈ fatty alcohols, for example from coconut oil alcohol, tallow fatty alcohol, lauryl, myristyl, cetyl or stearyl alcohol or the C ₁₀ -C ₂₀ oxo alcohols and those half-esters of secondary alcohols of this chain length . Also preferred are alk (en) yl sulfates of the chain length mentioned which contain a synthetic, straight-chain alkyl radical prepared on a petrochemical basis and which have a degradation behavior analogous to that of the adequate compounds based on oleochemical raw materials. C ₁₆ -C ₁₈ alk (en) yl sulfates are particularly preferred from the point of view of washing technology. It can also be particularly advantageous, and particularly advantageous for machine washing agents, to use C ₁₆ -C ₁₈ -alk (en) yl sulfates in combination with lower melting anionic surfactants and in particular with those anionic surfactants which have a lower Krafft point and relatively low ones Washing temperatures of, for example, room temperature to 40 ° C. show a low tendency to crystallize. In a preferred embodiment of the invention, the compositions therefore contain mixtures of short-chain and long-chain fatty alkyl sulfates, preferably mixtures of C ₁₂ -C ₁₄ fatty alkyl sulfates or C ₁₂ -C ₁₈ fatty alkyl sulfates with C ₁₆ -C ₁₈ fatty alkyl sulfates and in particular C ₁₂ -C ₁₆ -Fatty alkyl sulfates with C ₁₆ -C ₁₈ fatty alkyl sulfates. In a further preferred embodiment of the invention, however, not only saturated alkyl sulfates but also unsaturated alkenyl sulfates with an alkenyl chain length of preferably C ₁₆ to C ₂₂ are used. This embodiment, mixtures of saturated, consisting predominantly of C ₁₆ sulfated fatty alcohols and unsaturated, predominantly from C ₁₈ existing sulfonated fatty alcohols preferred, for example those derived from solid or liquid fatty alcohol mixtures of the type HD-Ocenol ^® (a product of the applicant) derived. Weight ratios of alkyl sulfates to alkenyl sulfates from 10: 1 to 1: 2 and in particular from about 5: 1 to 1: 1 are preferred.

The sulfuric acid monoesters of the straight-chain or branched C ₇ -C ₂₁ alcohols ethoxylated with 1 to 6 mol of ethylene oxide, such as 2-methyl-branched C ₉ -C ₁₁ alcohols with an average of 3.5 mol of ethylene oxide (EO) or C ₁₂ - C ₁₈ fatty alcohols with 2 to 4 EO are suitable. Because of their high foaming behavior, they are used in detergents only in relatively small amounts, for example in amounts of 1 to 5% by weight.

Preferred anionic surfactants are also the salts of alkylsulfosuccinic acid, which are also referred to as sulfosuccinates or as sulfosuccinic acid esters and which are monoesters and / or diesters of sulfosuccinic acid with alcohols, preferably fatty alcohols and in particular ethoxylated fatty alcohols. Preferred sulfosuccinates contain C ₈ to C ₁₈ fatty alcohol residues or mixtures thereof. Particularly preferred sulfosuccinates contain a fatty alcohol residue which is derived from ethoxylated fatty alcohols, which in themselves are nonionic surfactants (description see below). Again, sulfosuccinates whose fatty alcohol residues are derived from ethoxylated fatty alcohols with a narrow homolog distribution are particularly preferred. It is also possible to use alk (en) ylsuccinic acid with preferably 8 to 18 carbon atoms in the alk (en) yl chain or salts thereof.

Preferred anionic surfactant mixtures contain combinations of alk (en) yl sulfates, in particular mixtures of saturated and unsaturated fatty alk (en) yl sulfates, and Alkylbenzenesulfonates, sulfated fatty acid glycerol esters and / or α-sulfofatty acid esters. Mixtures which contain alk (en) yl sulfates as anionic surfactants are particularly preferred and alkylbenzenesulfonates, alk (en) ylsulfates and α-sulfofatty acid methyl esters and / or contain sulfated fatty acid glycerol esters.

Other suitable anionic surfactants are, in particular, soaps, preferably in amounts of 0.1 to 5% by weight. Suitable are, for example, saturated fatty acid soaps, such as the salts of lauric acid, myristic acid, palmitic acid or stearic acid, and in particular soap mixtures derived from natural fatty acids, for example coconut, palm kernel or tallow fatty acids. In particular, those soap mixtures are preferred which are composed of 50 to 100% by weight of saturated C ₁₂ -C ₂₄ fatty acid soaps and 0 to 50% by weight of oleic acid soap.

The anionic surfactants and soaps can be in the form of their sodium, potassium or ammonium salts as well as soluble salts of organic bases, such as mono-, di- or Triethanolamine. The anionic surfactants are preferably in the form of their Sodium or potassium salts, especially in the form of the sodium salts.

The nonionic surfactants used are preferably alkoxylated, advantageously ethoxylated, in particular primary alcohols having preferably 8 to 18 carbon atoms and an average of 1 to 12 moles of ethylene oxide (EO) per mole of alcohol, in which the alcohol radical can be linear or preferably methyl-branched in the 2-position or may contain linear and methyl-branched radicals in the mixture, as are usually present in oxo alcohol radicals. However, alcohol ethoxylates with linear residues of alcohols of native origin with 12 to 18 carbon atoms, for example from coconut, palm, tallow fat or oleyl alcohol, and an average of 2 to 8 EO per mole of alcohol are particularly preferred. The preferred ethoxylated alcohols include, for example, C ₁₂ -C ₁₄ alcohols with 3 EO or 4 EO, C ₉ -C ₁₁ alcohol with 7 EO, C ₁₃ -C ₁₅ alcohols with 3 EO, 5 EO, 7 EO or 8 EO, C ₁₂ -C ₁₈ alcohols with 3 EO, 5 EO or 7 EO and mixtures thereof, such as mixtures of C ₁₂ -C ₁₄ alcohol with 3 EO and C ₁₂ -C ₁₈ alcohol with 5 EO. The degrees of ethoxylation given represent statistical averages, which can be an integer or a fraction for a specific product. Preferred alcohol ethoxylates have a narrow homolog distribution (narrow range ethoxylates, NRE). In addition to these nonionic surfactants, fatty alcohols with more than 12 EO, for example those up to about 80 EO, can also be used. Examples include tallow fatty alcohol with 14 EO, 25 EO, 30 EO or 40 EO.

In addition, alkyl glycosides of the general formula RO (G) _x can also be used as further nonionic surfactants, in which R denotes a primary straight-chain or methyl-branched, in particular methyl-branched aliphatic radical having 8 to 22, preferably 12 to 18, C atoms and G is the symbol which stands for a glycose unit with 5 or 6 carbon atoms, preferably for glucose. The degree of oligomerization x, which indicates the distribution of monoglycosides and oligoglycosides, is any number between 1 and 10; x is preferably 1.2 to 1.4.

Also nonionic surfactants of the amine oxide type, for example N-cocoalkyl-N, N-dimethylamine oxide and N-tallow alkyl-N, N-dihydroxyethylamine oxide, and the Fatty acid alkanolamides can be suitable. The amount of these nonionic surfactants is preferably not more than that of the ethoxylated fatty alcohols, especially not more than half of it.

in der R²CO für einen aliphatischen Acylrest mit 6 bis 22 Kohlenstoffatomen, R³ für Wasserstoff, einen Alkyl- oder Hydroxyalkylrest mit 1 bis 4 Kohlenstoffatomen und [Z] für einen linearen oder verzweigten Polyhydroxyalkylrest mit 3 bis 10 Kohlenstoffatomen und 3 bis 10 Hydroxylgruppen steht.Other suitable surfactants are polyhydroxy fatty acid amides of the formula (I),

in the R ² CO for an aliphatic acyl radical having 6 to 22 carbon atoms, R ³ for hydrogen, an alkyl or hydroxyalkyl radical with 1 to 4 carbon atoms and [Z] for a linear or branched polyhydroxyalkyl radical with 3 to 10 carbon atoms and 3 to 10 hydroxyl groups stands.

The tablets contain the nonionic surfactants in a preferred embodiment in amounts up to 20% by weight.

Tools coated with hard plastic as well as uncoated Tablets with smooth surfaces, so that in most cases on a coating of the Stamp with soft plastic could be dispensed with. However, it is preferred that the pressing tools are made of high-strength material.

Other preferred ingredients are alkaline inorganic salts in water, which are preferably up to 15% by weight in the tablets. To this inorganic alkaline salts include bicarbonates, carbonates or mixtures of these; preferred are alkali carbonate and especially Sodium carbonate used.

Furthermore, the tablets can have up to 20% by weight of water which is neutral in water inorganic salts, preferably sulfates and chlorides, especially in the form of their Contain sodium and / or calcium salts. Their content in the tablets is preferably up to about 20% by weight.

Peroxy bleach is another important ingredient in tablets to call. Their content in the bleaching according to the invention Tablets is 20 to 50 wt .-% and in particular 25 to 45 wt .-%.

Among the compounds which serve as bleaching agents and supply H ₂ O ₂ in water, sodium perborate tetrahydrate and sodium perborate monohydrate are of particular importance. Further bleaching agents which can be used are, for example, sodium percarbonate, peroxypyrophosphates, citrate perhydrates and H ₂ O ₂ -producing peracidic salts or peracids, such as perbenzoates, peroxophthalates, diperazelaic acid or diperdodecanedioic acid. Peroxy bleaching agents which deliver 10 to 20% active oxygen per mole of component are particularly preferred.

In order to achieve an improved bleaching effect when washing at temperatures of 60 ° C and below, bleach activators can be incorporated into the preparations. Examples of these are N-acyl or O-acyl compounds which form organic peracids with H ₂ O ₂ , preferably N, N'-tetraacylated diamines, furthermore carboxylic acid anhydrides and esters of polyols such as glucose pentaacetate. Other known bleach activators are acetylated mixtures of sorbitol and mannitol, as described, for example, in European patent application EP-A-0 525 239 . The bleach activators contain bleach activators in the usual range, preferably between 1 and 10% by weight and in particular between 3 and 8% by weight. Particularly preferred bleach activators are N, N, N ', N'-tetraacetylethylene diamine (TAED), 1,5-diacetyl-2,4-dioxo-hexahydro-1,3,5-triazine (DADHT) and acetylated sorbitol-mannitol mixtures (SORMAN). The bleach activators can in particular also be used in granular form as a compound in the pressing.

The tablets according to the invention which are used as bleaching tablets, ie as bleach boosters are used, contain peroxy bleach in amounts of 20 to 50 wt .-% and especially in amounts of 25 to 45% by weight. A content of percarbonate in Amounts of 10 to 40 wt .-% may be particularly advantageous if in particular low percarbonate contents below 20% by weight, further peroxy bleaching agents be used.

The tablets can also contain other ingredients of washing or cleaning agents contain. These include common soil release and soil repellent connections, however also solubility improvers, graying inhibitors, foam inhibitors, optical Brighteners, enzymes, fabric softening agents as well as colors and fragrances. Your salary in the tablets according to the invention preferably do not exceed 10% by weight.

The agents can also contain components that allow oil and fat to be washed out made of textiles. This effect is particularly evident if a textile is soiled that has already been washed several times with one detergent according to the invention, which contains this oil and fat-dissolving component, is washed. The preferred oil and fat dissolving components include for example nonionic cellulose ethers such as methyl hydroxypropyl cellulose with a Proportion of 15 to 30% by weight of methoxyl groups and of hydroxypropoxyl groups from 1 to 15% by weight, based in each case on the nonionic cellulose ether, and also from known polymers of phthalic acid and / or Therephthalic acid or its derivatives, in particular polymers Ethylene terephthalates and / or polyethylene glycol terephthalates.

The agents can also contain components that determine the solubility of individual Components of the tablets and thus also the dissolution rate of the tablet itself influence positively. The preferred additional ingredients used include in addition to the fatty alcohols already described with 10 to 80 moles of ethylene oxide per mole Fatty alcohol in particular polyethylene glycols with a relative molecular weight between 200 and 4000.

When used in machine washing processes, it can be advantageous to add conventional foam inhibitors to the agents. Suitable foam inhibitors are, for example, soaps of natural or synthetic origin, which have a high proportion of C ₁₈ -C ₂₄ fatty acids. Suitable non-surfactant-like foam inhibitors are, for example, organopolysiloxanes and their mixtures with microfine, optionally silanized silica, and paraffins, waxes, microcrystalline waxes and their mixtures with silanized silica or bistearylethylenediamide. Mixtures of various foam inhibitors are also used with advantages, for example those made of silicones, paraffins or waxes. The foam inhibitors, in particular silicone or paraffin-containing foam inhibitors, are preferably bound to a granular, water-soluble or dispersible carrier substance. Mixtures of paraffins and bistearylethylenediamides are particularly preferred.

Enzymes come from the class of proteases, lipases, amylases, cellulases or their mixtures in question. Bacterial strains or are particularly suitable Mushrooms such as Bacillus subtilis, Bacillus licheniformis and Streptomyces griseus enzymatic agents. Proteases of the subtilisin type and in particular proteases obtained from Bacillus lentus are used. Are there Enzyme mixtures, for example from protease and amylase or protease and lipase or protease and cellulase or from cellulase and lipase or from protease, amylase and Lipase or protease, lipase and cellulase, but especially cellulase-containing Mixtures of special interest. Peroxidases or oxidases have also become proved suitable in some cases. The enzymes can be adsorbed on carriers and / or embedded in coating substances in order to prevent them from premature decomposition protect. The proportion of enzymes, enzyme mixtures or enzyme granules can, for example about 0.1 to 5% by weight, preferably 0.1 to about 2% by weight.

The salts come from as stabilizers, in particular for per-compounds and enzymes Polyphosphonic acids, especially 1-hydroxyethane-1,1-diphosphonic acid (HEDP), Diethylenetriaminepentamethylenephosphonic acid (DETPMP) or Ethylenediaminetetramethylenephosphonic acid into consideration.

Graying inhibitors have the task of removing the dirt detached from the fiber in the To keep the fleet suspended and thus prevent graying. For this are water-soluble colloids mostly of an organic nature, for example the water soluble salts of polymeric carboxylic acids, glue, gelatin, salts of Ether carboxylic acids or ether sulfonic acids of starch or cellulose or salts of acidic sulfuric acid esters of cellulose or starch. Also water-soluble, acidic Group-containing polyamides are suitable for this purpose. Furthermore, use soluble starch preparations and starch products other than the above, e.g. degraded starch, aldehyde starches, etc. Polyvinylpyrrolidone can also be used. However, cellulose ethers, such as carboxymethyl cellulose (sodium salt), are preferred. Methyl cellulose, hydroxyalkyl cellulose and mixed ethers, such as methyl hydroxyethyl cellulose, Methyl hydroxypropyl cellulose, methyl carboxymethyl cellulose and their mixtures and polyvinylpyrrolidone, for example in amounts of 0.1 to 5% by weight, based on the funds used.

As optical brighteners, the agents can be derivatives of diaminostilbenedisulfonic acid or whose alkali metal salts contain. Suitable are e.g. Salts of 4,4'-bis (2-anilino-4-morpholino-1,3,5-triazinyl-6-amino) stilbene-2,2'-disulfonic acid or similarly constructed Compounds which instead of the morpholino group a diethanolamino group, a Carry a methylamino group, an anilino group or a 2-methoxyethylamino group. Brighteners of the substituted diphenylstyryl type may also be present, e.g. the alkali salts of 4,4'-bis (2-sulfostyryl) diphenyl, 4,4'-bis (4-chloro-3-sulfostyryl) diphenyl, or 4- (4-chlorostyryl) -4 '- (2-sulfostyryl) diphenyl. Mixtures of the aforementioned brighteners can be used.

The tablets according to the invention can consist of several sub-components, as described in patent application WO-A-90/02165 . It is therefore preferred that the tablets are produced by mixing at least 2 previously prepared granular powder components and then compressing this mixture, the total amount of the anionic surfactants in one component and 75 to 100% by weight in the other component. % of the total amount of nonionic surfactants is included if these substances are used. Other subcomponents can also be used to produce the tablets, these can in particular contain bleaching agents and / or bleach activators or, for example, also enzymes, defoamers and fragrances.

But it is also possible that the various components do not become one Tablet is compressed, but that tablets are obtained which have several layers, thus have at least 2 layers. It is also possible that these different Layers have different dissolving speeds. This can be advantageous application properties of the tablets result. If, for example There are components in the tablets that have a mutually negative effect, so it is possible to integrate the one component in the quick-dissolving layer and incorporate the other component into a slower soluble layer so that the first Component has already reacted when the second goes into solution. In another preferred embodiment of the invention, a tablet consists of at least three Layers, i.e. two outer and at least one inner layer, at least in One of the inner layers contains a peroxy bleach, the two outer ones However, layers are free of peroxy bleach. Furthermore, it is also possible Peroxy bleach and any existing bleach activators and / or enzymes spatially separated in a tablet. Such multilayer tablets have the advantage that they do not have only one induction chamber or one Dosing device which is added to the wash liquor can be used; rather, in such cases it is also possible to have direct contact with the tablet Put textiles in the machine without bleaching and the like would be feared.

Examples

The tablets of the following examples were prepared in such a way that the appropriate components mixed and then in a hydraulically working Press (company Kürschner, Federal Republic of Germany) for press prints in the range of about 10 to 150 bar were produced.

A tablet was produced from a mixture which contained 58% by weight of SKS- ^6® , 30% by weight of perborate monohydrate, 10.5% by weight of a TAED granulate and 1% by weight of methylhydroxypropyl cellulose. The tablet had a diameter of 23 mm, a height of 10 mm and a weight of 20 g.

Claims (18)

1. A bleaching tablet containing builders, characterized in that the tablet contains

   a) 20 to 80% by weight and preferably 30 to 60% by weight of amorphous, partly crystalline and/or crystalline layer-form sodium silicates corresponding to the formula Na₂Si_xO_2x1AyH₂O where x is a number of 1.9 to 4 and y is a number of 0 to 20, preferred values for x being 2, 3 or 4,

   b) 20 to 50% by weight and preferably 25 to 45% by weight of peroxy bleaching agent

   but no zeolite, with the proviso that the tablet only contains water in such quantities that the maximum theoretical water binding capacity of the ingredients is not exceeded.
2. A tablet as claimed in claim 1, characterized in that it contains either crystalline layer-form sodium silicates or X-ray-amorphous silicates or crystalline layer-form sodium silicates and X-ray-amorphous silicates in a ratio by weight of 10:1 to 1:10.
3. A tablet as claimed in claim 1 or 2, characterized in that it is free from typical amorphous silicates of the waterglass type.
4. A tablet as claimed in claim 1 or 2, characterized in that it contains amorphous silicates of the waterglass type in combination with crystalline layer-form sodium silicates and/or X-ray-amorphous silicates, the content of amorphous silicates of the waterglass type preferably not exceeding 20% by weight and, more preferably, 15% by weight, based on the total quantity of silicates present in the tablet.
5. A tablet as claimed in any of claims 1 to 4, characterized in that it is present in overdried form.
6. A tablet as claimed in any of claims 1 to 5, characterized in that it contains disintegrating agents and/or tabletting aids.
7. A tablet as claimed in any of claims 1 to 6, characterized in that it contains phosphates, the phosphate content preferably being limited to at most 50% by weight and, more preferably, to at most 30% by weight.
8. A tablet as claimed in any of claims 1 to 7, characterized in that it contains up to 40% by weight of anionic surfactants and/or soaps.
9. A tablet as claimed in any of claims 1 to 8, characterized in that it contains up to 20% by weight of nonionic surfactants.
10. A tablet as claimed in any of claims 1 to 9, characterized in that it contains at least two powder-form or granular components prepared beforehand, of which the first contains the total quantity of anionic surfactants while the second contains 75 to 100% by weight of the total quantity of nonionic surfactants.
11. A tablet as claimed in any of claims 1 to 10, characterized in that it consists of at least two layers optionally dissolving at different rates.
12. A tablet as claimed in any of claims 1 to 11, characterized in that it consists of at least three layers, a peroxy bleaching agent being present in at least one of the inner layers.
13. A process for the production of the tablets claimed in any of claims 1 to 12, characterized in that the premixes to be tabletted are produced by mixing the individual ingredients which are made up at least partly in the form of a granular compound.
14. A process as claimed in claim 13, characterized in that the tabletting process is carried out in the absence of water.
15. A process as claimed in claim 13 or 14, characterized in that roll-compacted crystalline layer-form sodium disilicates, which are optionally impregnated with liquid to wax-like components, for example nonionic surfactants, are used as the granular compound.
16. A process as claimed in any of claims 13 to 15, characterized in that, before tabletting, at least two powder-form or granular compounds are produced, the first of which contains the total quantity of anionic surfactants while the second contains 75 to 100% by weight of the total quantity of nonionic surfactants.
17. A process as claimed in any of claims 13 to 16, characterized in that a tablet with at least two layers optionally dissolving at different rates is produced.
18. A process as claimed in any of claims 13 to 17, characterized in that a tablet with at least three layers is produced, at least one of the inner layers containing a peroxy bleaching agent.