EP0743978A1

EP0743978A1 - Tablet with builder substances

Info

Publication number: EP0743978A1
Application number: EP95908245A
Authority: EP
Inventors: Wolfgang Seiter; Dieter Jung; Otto Koch; Birgit Stevermann
Original assignee: Henkel AG and Co KGaA
Current assignee: Henkel AG and Co KGaA
Priority date: 1994-02-10
Filing date: 1995-02-01
Publication date: 1996-11-27
Anticipated expiration: 2015-02-01
Also published as: DE59509220D1; US5900399A; EP0743978B1; DE4404279A1; EP0965565A1; ATE200794T1; ES2157320T3; WO1995021908A1

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

"Tablet with builder substances"

The invention relates to tablets, preferably washing or cleaning tablets, in particular detergent tablets or compounds in tabulated form for detergents which contain silicate builder substances.

Detergent tablets have a number of advantages over powdered detergents, 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, tablets of this type often have inadequate disintegration and dissolving properties during use. Further 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 the pressing, the total amount of the anionic surfactants in one component and the majority of the nonionic surfactants in the other component are included. The component containing anionic surfactants 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 present.

Crystalline layered sodium silicates of the formula Na Si _x θ2χ + ι * yH2θ, 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 are preferred values for x 2, 3 or 4 , can substitute phosphates and zeolites. Such crystalline layered silicates are described, for example, in the European patent application EP-A-0 164 514. Preferred crystalline layered silicates are those in which M represents sodium and x assumes the values 2 or 3. In particular, ^'sodium disilicates Na2Si2θs * yH2θ are both .beta.- and δ preferred, with beta-sodium disilicate being er¬ hold, for example, by the method described in International Patent Application W0-A 91/08171. β-sodium disilicate is commercially available under the name SKS 7 ( ^R ), fr-sodium disilicate is available under the name SKS δC *) (commercial products from Hoechst AG, Federal Republic of Germany). These powders generally have a bulk density of less than 600 g / l and have a high proportion of fine particles, usually more than 30% by weight, with a particle size of less than 0.1 mm. Since crystalline layered silicates suffer losses in their action as builders in the spray drying of detergent-containing or detergent-containing detergents, presumably caused by the partial destruction of their crystalline structure, they should preferably be incorporated into detergent or detergent by other process methods. However, due to their high proportion of fine grains and thus their dusty structure, these powders are also not suitable for serving as an additive component to other granular constituents 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 safety of the process is endangered and additional checks of the mixing and granulating tools are necessary, but also that the silicatic 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 M2θ: Siθ2 ~ ratio of 1: 1.9 to 1: 4.0, where M preferably stands for sodium and / or potassium, can generally be spray-dried, but the skilled worker knows that the spray drying of slurries which also contain zeolite in addition to the amorphous silicates leads to negative interactions, which reduces the exchange capacity of the zeolite. is set and can deposit deposits that are difficult to remove 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 developing an advantageous offer form for products which contain amorphous and / or crystalline silicates. Both the procedural security and the stability of any other components of the offer form should be increased. In addition, the builder properties should be retained. A further object of the invention was to offer builder forms containing builder substance which are sufficiently soluble or dispersible for the intended purpose.

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

The invention accordingly relates to a tablet containing builder substances, this tablet containing amorphous, partially crystalline and / or crystalline layered sodium silicates of the formula Na2Si _x θ2χ ₊ ι * yH2θ in amounts of 2 to 100% by weight and x containing a number of 1, 9 to 4 and y is a number from 0 to 20 and are preferred values for x 2, 3 or 4, 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 determined in the manner described below. Some components of the tablets form stable hydrates at an assumed storage temperature of 15 to 45 ° C. This applies, for example, to zeolite. In contrast, constituents such as sodium sulfate and polymeric polycarboxylates are counted as anhydrous substances, although it is known that these are generally present in hydrated form in granules. Crystalline layered sodium silicates are also counted anhydrous, while amorphous sodium silicates for example, can have a water content of up to about 22% by weight. The sum of the crystal water proportions from the stable hydrates gives the maximum theoretical water content of the tablet according to the invention. It may even be preferred that the tablet is in over-dried form, that is to say contains less water than corresponds to the maximum theoretical water-binding capacity or can be absorbed by the tablet ingredients in a stable manner.

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 Range from 1 to 300 bar, advantageously in the range from about 5 to 200 bar and in particular between 10 and 150 bar. 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 wax-like components, for example nonionic surfactants. In particular, this enables water-free pre-assembly, which is particularly advantageous. In this way, break-proof tablets with good breaking strength that are sufficiently quickly soluble 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.

Tools coated with hard plastic as well as uncoated delivered tablets with smooth surfaces, so that in most cases len the 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.

Practically all sensible, manageable forms of configuration come into consideration as the spatial form, as long as they meet the requirements that the contact with the tableting apparatus during the manufacturing process is relatively low. Cylindrical configurations with an oval or circular cross section of the type specified below are preferred. A tablet produced in this way preferably has a weight of 10 to 120 g, in particular 20 to 100 g, the diameter of the tablets usually being less than 100 mm . Preferred detergent tablets have a maximum diameter of 80 mm and in particular from 30 to 80 mm. However, it is also possible, and particularly preferred with a view to improved solubilities, to use several, that is to say at least 2, tablets with the same or different compositions. These tablets preferably have a weight of 10 to 40 g, with diameters of 20 to 50 mm being preferred. The diameter / height ratio of the tablets should be optimized in such a way that the least possible abrasion on the vertical walls of the tabletting apparatus (high diameter / low height) with sufficient stability and a surface that is not too large (small diameter / large) Height) is guaranteed. Preferred diameter / height ratios of the cylindrical compacts are approximately 0.5: 1 to 10: 1, in particular 1: 1 to 8: 1.

The content of the tablets in amorphous, partially crystalline and / or crystalline layered sodium silicates can vary within a wide range. Which quantity ranges are actually used depends on the area of application in which this tablet is to be used. If such a tablet serves as a tableted washing or cleaning agent, preferred contents of amorphous, partially crystalline and / or crystalline layered sodium silicates are 5 to 60% by weight and in particular 10 to 40% by weight. However, if such tablets are only used as a compound and in particular as a water softening tablet, preferred contents of amorphous, partially crystalline and / or crystalline layered sodium silicates are 20 to 80% by weight and in particular 30 to 60% by weight. This also applies to bleaching tablets, which can be added to a wash liquor as bleach boosters.

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 Na2θ: Siθ2 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-0488868 and EP-A-0561 565. Such compounds are known under the name Nabion lδ ( ^R ) (commercial product from Rδhne) -Poulenc) commercially available. A particularly preferred embodiment of silicates is, however, those X-ray amorphous silicates as described in the older German patent application P 4400024.3. Therefore, tablets are preferred which contain either crystalline layered sodium silicates of the type specified 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 the usual 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 being Water glass type advantageously does not exceed 20% by weight and in particular 15% by weight, based in each case on the total amount of silicates present in the tablet.

The tablets can contain up to 98% by weight of further ingredients of washing or cleaning agents. It is particularly preferred that the tablets have conventional tableting aids and / or disintegrants.

Auxiliaries are regarded as disintegrants which have a positive influence on the dissolving or disintegrating process in the aqueous application phase. These disintegrants can be inorganic and / or organic in nature. Typical inorganic-based disintegrants are, for example, swellable sheet silicates such as bentonites. Organic disintegrants can Turstoffe or their derivatives based on starch or cellulose. Here, for example, crosslinked potato starch, microcrystalline cellulose powder, but in particular also conventional ingredients of washing or cleaning agents such as the salts of polymeric polyacrylates or polyethacrylates, for example those with a low relative molecular weight between 1000 and 5000, but also methyl celluloses and / or hydroxypropyl celluloses or methyl hydroxypropyl celluloses.

Other examples are acetates or percarbonates. The latter are preferably used in tablets containing bleach or directly in the bleaching tablets. It is customary to use disintegrants of this type in amounts of up to about 15% by weight, based on the tablet. Due to the use of water-soluble silicates, it is sufficient in most cases for the tablets according to the invention to use the disintegrants in amounts of well below 10% by weight, preferably in amounts of up to 5% by weight and in particular even less. When using poly (meth) acrylates and / or nonionic cellulose ethers, amounts of around 1% by weight generally lead to very good results.

In contrast to the disintegrants, tabletting aids ensure better cohesion of the individual powdery or granular constituents and thus contribute to the stability of the tablet. However, there is a whole range of disintegrants which also serve as tablet auxiliaries or binders. These include, for example, starch, starch and cellulose derivatives, but also gelatin and polyvinyl pyrrolidone. Other preferred binders are, for example, liquid to pasty nonionic surfactants which are liquid at the processing temperature.

The disintegrants and tableting aids are preferably used in dry form or in a form dissolved or suspended in nonionic surfactant. An aqueous form of use is less preferred because water may only be added during the process in such quantities that the maximum theoretical water-binding capacity of the tablet ingredients is not exceeded. In a particularly preferred embodiment of the invention, therefore, no ingredient is in the form of an aqueous solution or suspension used and the pressing is carried out without the addition of water.

In a preferred embodiment of the invention, the tablets contain in particular further customary builder substances. These include inorganic builder substances such as zeolite and / or phosphates or organic builder substances such as polycarboxylates and / or polymeric polycarboxylates.

Tablets are preferred which contain 0.5 to 98% by weight of water-containing zeolite and / or phosphates, the phosphate content preferably being at most 50% by weight and in particular at most 30% by weight ¬ is limited. However, in a water softening tablet, which is a preferred embodiment of the invention, 0 to 80% by weight, preferably 5 to 80% by weight and in particular 10 to 60% by weight of water-containing zeolite and / or phosphate present. Bleaching tablets, on the other hand, are preferably free of zeolite in order to exclude negative interactions, but may optionally contain phosphates.

The fine crystalline, synthetic and bound water containing zeolite used is preferably zeolite NaA in detergent quality. However, zeolite NaX, zeolite P and mixtures of A, X or P are also suitable. The zeolite can be used either as a spray-dried powder or as a granular compound which, for example, contains up to about 50% by weight of other constituents such as nonionic surfactants and cellulose ethers and / or contains polymeric polycarboxylates. Suitable powdered zeolites have an average particle size of less than 10 μ (volume distribution; measurement method: Coulter counter) and preferably contain 18 to 22% by weight, in particular 20 to 22% by weight, of bound water.

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. Water softening tablets preferably contain 0 to 50% by weight, in particular 0.5 to 30% by weight and advantageously 2 to 20% by weight of polycarboxylates and additionally preferably 0 to 15% by weight, in particular 0.5 to 12th % By weight and advantageously 1 to 10% by weight of polymeric polycarboxylates. 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 thereof. 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 from 5,000 to 200,000, preferably from 10,000 to 120,000 and in particular from 50,000 to 100,000. Terpolymeric polycarboxylates are also particularly preferred, for example those which are salts of acrylic acid and of monomers Maleic acid and vinyl alcohol or vinyl alcohol derivatives (DE-A-4300772) or the monomers as salts of acrylic acid and 2-alkylallylsulfonic acid and sugar derivatives (DE-C-4221 381).

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

Other suitable builder systems are oxidation products of carboxyl group-containing polyglucosans and / or their water-soluble salts, as described, for example, in international patent application WO-A-93/08251 or their production, for example, in international patent application WO-A-93 / 16110.

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 derived from dialdehydes such as glyoxal, glutar aldehyde, terephthalaldehyde and mixtures thereof 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. The anionic surfactants used are, for example, those of the sulfonate and sulfate types.

Preferred surfactants of the sulfonate type are Cg-Ci3-alkylbenzenesulfonates, olefin sulfonates, i.e. Mixtures of alkene and hydroxyalkanesulfonates and disulfonates, such as those obtained, for example, from Ci2-Ci8 monoolefins with a terminal or internal double bond by sulfonation with gaseous sulfur trioxide and subsequent alkaline or acidic hydrolysis of the sulfonation products.

Also suitable are alkanesulfonates obtained from C 1 -C 8 -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 esters of hydrogenated coconut, palm kernel or Taig¬ fatty acids.

Other suitable anionic surfactants are sulfonated fatty acid glycerol esters. Fatty acid glycerol esters are to be understood as the mono-, di- and triesters as well as their mixtures, as they are 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 be preserved. Preferred sulfated fatty acid glycerol esters are the sulfonation products of saturated fatty acids having 6 to 22 carbon atoms, for example capric 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 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, such as it is specified in the international patent application WO-A-91/09009.

Alk (en) yl sulfates are the Schwefelsäurehalbester the C ^ -cis-fatty alcohols are, for example, from coconut fatty alcohol, tallow fatty alcohol, lauryl, myristyl ristyl-, cetyl or stearyl alcohol, or Cιo-C2θ ^_ 0xoalkohole and have those Halbester secondary alcohols this chain length preferred. Also preferred are alk (en) yl sulfates of the chain length mentioned which contain a synthetic, petrochemical-based straight-chain alkyl radical which have a degradation behavior analogous to that of the corresponding compounds based on oleochemical raw materials. Cχ6-Ci8-alk (en) yl sulfates are particularly preferred for washing technology reasons. It can also be particularly advantageous, and particularly advantageous for machine washing agents, to use Ci6-Ci8-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 Ci2-Ci4-fatty alkyl sulfates or Ci2-Ci8-fatty alkyl sulfates with Ci6-Ci8 ~ fatty alkyl sulfates and in particular Ci2-Ci6-fatty alkyl sulfates with Ci6-Ci8 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 6 to C 22 are used. In particular, mixtures of saturated, predominantly Ci6 sulfated Fatty alcohols and unsaturated, sulfated fatty alcohols consisting predominantly of CJS are preferred, for example those which are derived from solid or liquid fatty alcohol mixtures of the HD-Ocenol ( ^R ) type (commercial product of the applicant). Weight ratios of alkyl sulfates to alkenyl sulfates of 10: 1 to 1: 2 and in particular of about 5: 1 to 1: 1 are preferred.

The sulfuric acid monoesters of the straight-chain or branched C7 ~ C2i alcohols ethoxylated with 1 to 6 moles of ethylene oxide, such as 2-methyl-branched Cg-Cn alcohols with an average of 3.5 moles of ethylene oxide (EO) or C _j 2 -Ci8 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 Cs to Ci8 fatty alcohol residues or mixtures thereof. Particularly preferred sulfosuccinates contain a fatty alcohol residue which is derived from ethoxylated fatty alcohols which, viewed in isolation, are nonionic surfactants (for a description, see below). Again, sulfosuccinates, the fatty alcohol residues of which 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 sulfofatty acid esters. In particular, mixtures are preferred which contain alk (en) yl sulfates and alkylbenzenesulfonates, alk (en) yl sulfates and methyl α-sulfofatty acid and / or sulfated fatty acid glycerol esters as anionic surfactants. Other suitable anionic surfactants are, in particular, soaps, preferably in amounts of 0.1 to 5% by weight. For example, saturated fatty acid soaps are suitable, 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 saturated C12-C24 fatty acid soaps and 0 to 50% by weight oleic acid soap.

The anionic surfactants and soaps can be present in the form of their sodium, potassium or ammonium salts and 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, in particular 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 (E0) per mole of alcohol in which the alcohol radical has a methyl or linear branching, preferably in the 2-position may be 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 E0 per mole of alcohol are particularly preferred. The preferred ethoxylated alcohols include, for example, Ci2-Ci4 alcohols with 3 E0 or 4 E0, Cg-Cn alcohol with 7 E0, Ci3-Ci5 alcohols with 3 E0, 5 E0, 7 E0 or 8 E0, Ci2-Ci8- Alcohols with 3 E0, 5 E0 or 7 E0 and mixtures of these, such as mixtures of C12-Ci4 alcohol with 3 E0 and Ci2-Ci8 alcohol with 5 E0. 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 E0, for example those up to about 80 E0, can also be used. Examples of this are tallow fatty alcohol with 14 E0, 25 E0, 30 E0 or 40 E0. In addition, alkyl glycosides of the general formula R0 (G) _x , in which R is a primary straight-chain or methyl-branched, in particular methyl-branched aliphatic radical having 8 to 22, preferably 12 to 18, C., can also be used as further nonionic surfactants -Atoms means 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.

Nonionic surfactants of the amine oxide type, for example N-cocoalkyl-N.N-dimethyla inoxide and N-tallow alkyl-N.N-dihydroxyethylamine oxide, and the fatty acid alkanolamides may also be suitable. The amount of these non-ionic surfactants is preferably not more than that of the ethoxylated fatty alcohols, in particular not more than half of them.

Other suitable surfactants are polyhydroxy fatty acid amides of the formula (I),

R3

R ² -C0-N- [Z] (I)

in which R ^{2 is} C0 for an aliphatic acyl radical with 6 to 22 carbon atoms, R ^ 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.

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

Other preferred ingredients are alkaline organic salts in water, which are preferably up to 15% by weight in the tablets. These inorganic alkaline salts include in particular bicarbonates, carbonates or mixtures thereof; Alkali carbonate and especially sodium carbonate are preferably used. The tablets can furthermore contain inorganic salts which react neutral in water, preferably sulfates and chlorides, in particular in the form of their sodium and / or calcium salts. Their content in the tablets is preferably up to about 20% by weight.

A further embodiment of the invention relates to water softening tablets which are 0 to 30% by weight, but preferably 0.5 to 20% by weight and in particular 2 to 15% by weight, of the anionic surfactants, nonionic surfactants mentioned, alkaline or neutral reacting inorganic salts or mixtures of these.

Peroxy bleaching agents and bleach activators can be mentioned as further important ingredients of tablets. Of the compounds which provide H2O2 in water and serve as bleaching agents, sodium perborate tetrahydrate and sodium perborate monohydrate are of particular importance. Further usable bleaching agents are, for example, sodium percarbonate, peroxypyrophosphates, citrate perhydrates and H2O2-providing 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. The bleaching agent content of the tablets is preferably 15 to 60% by weight and in particular 10 to 50% by weight, advantageously using perborate monohydrate.

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 this are N-acyl or O-acyl compounds which form organic peracids with H2O2, preferably N, N'-tetraacylated diamines, furthermore carboxylic acid anhydrides and esters of polyols such as glucose sepentaacetate. 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 in (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.

Bleaching detergent tablets preferably contain peroxy bleach in amounts of 5 to 30% by weight and in particular 10 to 25% by weight. Tablets which are used as bleaching tablets, ie as bleach boosters in addition to other detergent formulations, which may be in tablet form, preferably contain peroxy bleaches in amounts of 20 to 50% by weight and especially in amounts of 25 to 45% by weight. A content of percarbonate in amounts of 10 to 40% by weight can be particularly advantageous if additional peroxy bleaching agents are used in particular at low percarbonate contents below 20% by weight. A preferred bleaching tablet is characterized in that it contains 20 to 80% by weight, preferably 30 to 60% by weight, of amorphous, partially crystalline and / or crystalline layered sodium likates of the formula given and 20 to 50, preferably 25 to 45% by weight peroxy bleach, but does not contain zeolite.

The tablets can also contain further ingredients of washing or cleaning agents. These include common soil release and soil repellent compounds, but also solubility improvers, graying inhibitors, foam inhibitors, optical brighteners, enzymes, fabric softening agents, and colorants and fragrances. Their content in the tablets according to the invention preferably does not exceed 10% by weight.

The agents can therefore also contain components which have a positive influence on the oil and fat washability from textiles. This effect is particularly evident when a textile is contaminated which has already been washed several times beforehand with a detergent according to the invention which contains this oil- and fat-dissolving component. The preferred oil- and fat-dissolving components include, for example, nonionic cellulose ethers such as methyl hydroxypropyl cellulose with a proportion of methoxyl groups of 15 to 30% by weight and of hydroxypropoxyl groups of 1 to 15% by weight, based in each case the nonionic cellulose ether, and the polymers of phthalic acid and / or the known from the prior art Therephthalic acid or its derivatives, in particular polymers of ethylene terephthalates and / or polyethylene glycol terephthalates.

The agents can also contain constituents which have a positive influence on the solubility of individual constituents of the tablets and thus also on the dissolution speed of the tablet itself. In addition to the already described fatty alcohols with 10 to 80 moles of ethylene oxide per mole of fatty alcohol, the preferred additional components used include, in particular, polyethylene glycols with a relative molecular weight of 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 Ci8 ~ C24 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 different foam inhibitors are also used with advantages, e.g. 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.

Suitable enzymes are those from the class of proteases, lipases, amylases, cellulases or mixtures thereof. Enzymes obtained from bacterial strains or fungi such as Bacillus subtilis, Bacillus licheniformis and Streptomyces griseus are particularly suitable. Proteases of the subtilisin type and in particular proteases which are obtained from Bacillus lentus are preferably used. Of particular interest here are enzyme mixtures, for example of protease and aylase or protease and lipase or protease and cellulase or of cellulase and lipase or of protease, amylase and lipase or protease, lipase and cellulase, but in particular mixtures containing cellulase . Peroxi- In some cases, these or oxidases have proven to be suitable. The enzymes can be adsorbed on carriers and / or embedded in coating substances in order to protect them against premature decomposition. The proportion of the enzymes, enzyme mixtures or enzyme granules can be, for example, about 0.1 to 5% by weight, preferably 0.1 to about 2% by weight.

The salts of polyphosphonic acids, in particular l-hydroxyethane-l, l-diphosphonic acid (HEDP), diethylenetriaminepentamethylenephosphonic acid (DETPMP) or ethylenediaminetetramethylenephosphonic acid are suitable as stabilizers, in particular for per compounds and enzymes.

Graying inhibitors have the task of keeping the dirt detached from the fiber suspended in the liquor and thus preventing graying. Water-soluble colloids of mostly organic nature are suitable for this, 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. Water-soluble polyamides containing acidic groups are also suitable for this purpose. Soluble starch preparations and starch products other than those mentioned above can also be used, e.g. degraded starch, aldehyde starches, etc. Polyvinylpyrrolidone can also be used. However, preference is given to cellulose ethers, such as carboxymethyl cellulose (sodium salt), methyl cellulose, hydroxyalkyl cellulose and mixed ethers, such as methyl hydroxyethyl cellulose, methyl hydroxypropyl cellulose, methyl carboxymethyl cellulose and mixtures thereof, and also polyvinylpyrrolidone, for example in amounts of 0.1 to 5% by weight , based on the funds used.

As optical brighteners, the agents can contain derivatives of diaminostilbenedisulfonic acid or its alkali metal salts. Suitable are, for example, salts of 4,4'-bis (2-anilino-4-morpholino-l, 3,5-triazinyl-6-amino) stilbene-2,2'-disulfonic acid or compounds of the same structure which contain an replace the morpholino group with a diethanolamino group, a methylamino group, an anilino group or a 2-methoxyethylamino group. Brighteners of the substituted diphenylstyryl type may also be present, for example the alkali salts of 4,4'-bis (2-sulfostyryl) diphenyl, 4,4'-bis (4-chloro-3-sulfostyryl) diphenyl ₁ or 4- (4-chlorostyryl) -4 '- (2- sulfostyryl) diphenyls. Mixtures of the aforementioned brighteners can also be used.

The tablets according to the invention - it is immaterial whether it is detergent tablets or additives to detergents or cleaning agents - can consist of several sub-components, as described in patent application WO-A-90/02165. So it is preferred that the tablets are produced by mixing at least 2 previously prepared powdery to granular components and then compressing this mixture, the total amount of anionic surfactants in one component and 75 to 100% by weight in the other component. -% of the total amount of nonionic surfactants is included. 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.

However, it is also possible that the various components are not pressed into a uniform tablet, but that tablets are obtained which have several layers, that is to say at least 2 layers. It is also possible for these different layers to have different dissolution rates. This can result in advantageous application properties of the tablets. If, for example, components are contained in the tablets which mutually influence one another negatively, it is possible to integrate one component in the rapidly soluble layer and to incorporate the other component in a more slowly soluble layer, so that the first Component has already reacted when the second goes into solution. In a further preferred embodiment of the invention, a tablet consists of at least three layers, that is to say two outer and at least one inner layer, wherein at least one of the inner layers contains a peroxy bleach, but the two outer layers are free of peroxy bleach ¬ are medium. Furthermore, it is also possible to spatially separate peroxy bleaching agents and any bleach activators and / or enzymes that may be present in one tablet. Such multilayer tablets have the advantage that they not only have a dispenser or can be inserted via a metering device which is added to the wash liquor; rather, it is also possible in such cases to put the tablet in direct contact with the textiles in the machine without fear of bleaching and the like.

Ultimately, a washing process is also claimed in which several, but at least two tablets with the same or different composition are used for a single wash cycle. In particular, a combination of tablets according to the modular principle is possible. This means that, for example, one tablet is used as the basic detergent in one wash cycle, this tablet containing in particular tenides and the silicates used according to the invention and further constituents of conventional detergents or cleaning agents, but is free from bleaching agents. In addition to this tablet, a water softening tablet and / or a bleaching tablet can then be used. The addition of a water softening tablet can be helpful in areas with very high water hardness in tap water, while the use of an additional bleaching tablet can be made dependent on the type of textiles to be washed and the stains.

The tablet (s) can also be positioned on the laundry in the washing machine directly at the beginning of the washing process by means of a dosing container. Since high concentrations of active substances can be present at the beginning of the washing process with little moisture, the formation of stains on the laundry (for example due to the action of bleach) cannot be ruled out. This "spotting effect" is avoided, for example, by designing the dosing container like a basket. In the interior of the basket there is a water-permeable sieve or net-like receptacle for the tablets. The outer basket prevents the molded body from lying directly on the textiles. It is preferred that the sieve-like or mesh-like receptacle is relatively narrow-meshed, so that fragments from the basket only pass into the wash liquor when their maximum particle diameter is significantly less than 10 mm and advantageously less than 5 mm . Examples

The tablets of the following examples were produced in such a way that the corresponding constituents were first mixed and then produced in a hydraulically operating press (company Kürschner, Federal Republic of Germany) at pressures in the range from about 10 to 150 bar.

Example 1: Detergent tablet without zeolite

A mixture of 8.6% by weight of Ci2-Ci8 fatty alcohol sulfate, 6.5% by weight of C12-Ciβ fatty alcohol with 5 EO, 1% by weight of Ci2-Ci8 sodium fatty acid soap, 29% by weight of crystalline layer Sodium disilicate (SKS-6 ( ^R ), commercial product of Hoechst AG, Federal Republic of Germany), 5.2% by weight sodium carbonate, 0.5% by weight amorphous sodium silicate (Na2θ: Siθ2 of 1: 3.0 ), 5% by weight of terpolymeric salt from acrylic acid, maleic acid and vinyl alcohol, prepared according to the teaching of German patent application DE-A-4300772.4, 20.5% by weight of sodium perborate monohydrate, 6.4% by weight of TAED granules, 1% by weight of a granular protease, 14% by weight of sodium sulphate, 1% by weight of methylhydroxypropyl cellulose, salts from solutions and 0.4% by weight of water were pressed into a tablet. The water came from the raw materials used and was not added. The fatty alcohol sulfate was introduced into the mixture via a compound which had been prepared in accordance with the teaching of the German patent application DE-A-4127323. The SKS-6 () was premixed with the nonionic surfactant and then added to the remaining ingredients. One tablet was sufficient as the sole detergent for one wash cycle and had a weight of 80 g. It had a diameter of 38 mm and a height of 15 mm.

Example 2: Detergent tablet with zeolite

A tablet was produced from a mixture containing 8% by weight of Ci2-Ci8 fatty alcohol sulfate, 6% by weight of Ci2-Ci8 fatty alcohol with 5E0, 1% by weight of Ci2-Ci8 sodium fatty acid soap, 11.5% by weight % crystalline layered sodium disilicate (SKS-6 ( ^R ), commercial product of Hoechst AG, Federal Republic of Germany), 15% by weight zeolite (based on anhydrous active substance), 5 % By weight sodium carbonate, 0.5% by weight amorphous sodium silicate (Na2θ: Siθ2 1: 3.0), 9% by weight trisodium citrate dihydrate, 20% by weight sodium perborate tetrahydrate, 6% by weight one TAED granules, 1% by weight of a granular protease, 9% by weight sodium sulfate, 1% by weight methyl hydroxypropyl cellulose, 0.5% by weight carboxymethyl cellulose (CMC), 0.6% by weight bentonite, 0.15% by weight of a granular foam inhibitor based on silicone oil, 0.2% by weight of perfume, 0.15% by weight of optical brightener, salts from solutions and 4.4% by weight of water. The water came from the raw materials used, in particular from the powdered zeolite used, and was not added. The fatty alcohol sulfate was again introduced into the mixture via a compound which had been produced in accordance with the teaching of the German patent application DE-A-41 27 323. The zeolite was used in the form of a spray-dried powder, the slurry to be spray-dried additionally containing small amounts of nonionic surfactant, CMC, sodium hydroxide solution and the bentonite and the remaining nonionic surfactant was additionally applied. One tablet was sufficient as the sole detergent for one wash cycle and had a weight of 80 g. It had a diameter of 38 mm and a height of 15 mm.

Example 3: Water softener tablet

A tablet was produced from a mixture which contained 5.7% by weight sodium carbonate, 67% by weight SKS-δ ( ^R ), 1% by weight methylhydroxypropylcellulose, 16% by weight trisodium citrate dihydrate, 8 % By weight of a terpolymeric salt of acrylic acid, maleic acid and vinyl alcohol, prepared according to the teaching of German patent application P 4300 772.4 and subsequent spray drying of a 38% by weight aqueous solution, 0.72% by weight of water, which is obtained from the raw materials used and was not additionally added, and contained 0.5% by weight sodium sulfate and the rest of further salts from the raw materials. The tablet had a diameter of 23 mm, a height of 10 mm and a weight of 20 g.

Example 4: Bleaching tablet

A tablet was made from a mixture containing 58% by weight

SKS-6 ( ^R ), 30% by weight perborate monohydrate, 10.5% by weight of a TAED granulate and 1% by weight of methyl hydroxypropyl cellulose. The tablet had a diameter of 23 mm, a height of 10 mm and a weight of 20 g.

Example 5: Basic detergent tablet

A tablet was produced from a mixture comprising 16.5% by weight of Ci2-Ci8 fatty alcohol sulfate, 12.4% by weight of Ci2-Ci8 fatty alcohol with 5 EO, 1.5% by weight of Ci2-Ci8- Sodium fatty acid soap, 12% by weight of crystalline layered sodium disilicate (SKS-6 ( ^R ), commercial product of Hoechst AG, Federal Republic of Germany), 20% by weight of zeolite (based on anhydrous active substance), 2% by weight % Sokalan CPδ ( ^R ), 10% by weight sodium carbonate, 0.5% by weight amorphous sodium silicate (Na2θ: Siθ2 1: 3.0), 1.5% by weight of a granular protease, 10% by weight Sodium sulfate, 1% by weight methyl hydroxypropyl cellulose, 1% by weight carboxymethyl cellulose (CMC), 1.3% by weight bentonite, 0.7% by weight of a granular foam inhibitor based on silicone oil, 0.2% by weight perfume, 0 , 15 wt .-% optical brightener, salts from the raw materials used and 6.2 wt .-% water. The water came from the raw materials used, in particular from the powdered zeolite used, and was not additionally added. The fatty alcohol sulfate was again introduced into the mixture via a compound which had been prepared in accordance with the teaching of the German patent application DE-A-41 27323. The zeolite was used in the form of a spray-dried powder, the slurry to be spray-dried additionally containing small amounts of Nioten sid, CMC, sodium hydroxide solution and the bentonite. One tablet weighed 40 g. It had a diameter of 35 mm and a height of 10 mm.

Example 6: Modular system made of tablets

1 tablet each, produced according to Examples 3, 4 and 5, was used in one wash.

Claims

claims

1. tablet containing builder substances, characterized in that this tablet contains amorphous, partially crystalline and / or crystalline layered sodium silicates of the formula Na2Si _x θ2 _{x +} ι ^# H2θ in amounts of 2 to 100% by weight and x contains a number of 1 , 9 to 4 and y is a number from 0 to 20 and are preferred values for x 2, 3 or 4, 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.

2. Tablet according to claim 1, characterized in that it contains either crystalline layered sodium silicates or X-ray amorphous silicates or that they contain crystalline layered sodium silicates and X-ray amorphous silicates in a weight ratio of 10: 1 to 1:10.

3. Tablet according to claim 1 or 2, characterized in that it is free of conventional amorphous silicates of the water glass type.

4. Tablet according to claim 1 or 2, characterized in that it contains amorphous silicates of the water glass type in combination with crystalline layered sodium silicates and / or X-ray amorphous silicates, the content of amorphous silicates of the water glass type preferably being 20% by weight. % and in particular 15% by weight, based in each case on the total amount of silicates present in the tablet, does not exceed.

5. Tablet according to one of claims 1 to 4, characterized in that it is in over-dried form.

6. Tablet according to one of claims 1 to 5, characterized in that it contains 5 to 60 wt .-%, preferably 10 to 40 wt .-% amorphous, partially crystalline and / or crystalline layered sodium silicates.

7. Tablet according to one of claims 1 to 6, characterized in that it contains disintegrants and / or tableting aids.

8. Tablet according to one of claims 1 to 7, characterized in that it contains 0.5 to 98% by weight of water-containing zeolite and / or phosphates, the content of phosphates preferably being at most 50% by weight and in particular is limited to a maximum of 30% by weight.

9. Tablet according to one of claims 1 to 8, characterized in that it contains up to 40 wt .-% anionic surfactants and / or soaps.

10. Tablet according to one of claims 1 to 9, characterized in that it contains up to 20 wt .-% nonionic surfactants.

11. Tablet according to one of claims 1 to 10, characterized in that it contains at least 2 previously prepared powdery to granular components, of which the first is the total amount of anionic surfactants and the second 75 to 100 wt .-% of the total amount of contains nonionic surfactants.

12. Tablet according to one of claims 1 to 11, characterized in that it consists of at least 2 layers, which may have different dissolving speeds.

13. Tablet according to one of claims 1 to 12, characterized in that it consists of at least 3 layers and contains at least one of the inner layers of a peroxy bleach.

14. Water softening tablet according to one of claims 1 to 13, characterized in that it contains 20 to 80% by weight, preferably 30 to 60% by weight, of amorphous, partially crystalline and / or crystalline layered sodium likates of the formula given, 0 to 80% by weight, preferably 5 to 80% by weight and in particular 10 to 60% by weight of water-containing zeolite and / or phosphate, 0 to 50% by weight, preferably 0.5 to 30% by weight and in particular 2 to 20% by weight of polycarboxylates, 0 to 15% by weight, preferably 0.5 to 12% by weight and in particular 1 to 10% by weight polymeric polycarboxylates and 0 to 30 wt .-%, preferably 0.5 to 20 wt .-% and in particular zu 2 to 15 wt .-% of anionic surfactants, nonionic surfactants, alkaline or neutral reacting inorganic salts or mixtures of these.

15. Bleaching tablet according to one of claims 1 to 13, characterized gekenn¬ characterized in that it 20 to 80 wt .-%, preferably 30 to 60 wt .-% of amorphous, partially crystalline and / or crystalline layered sodium silicates of the formula given and 20 to 50, preferably 25 to 45% by weight peroxy bleach, but containing no zeolite.

16. A process for the production of tablets according to one of claims 1 to 15, characterized in that the premixes intended for compression are produced by mixing the individual ingredients, which are at least partially present in pre-assembled form as a granular compound.

17. The method according to claim 16, characterized in that the pressing takes place without the addition of water.

18. The method according to claim 16 or 17, characterized in that roller-compacted crystalline layered sodium disilicates, which are optionally impregnated with liquid to wax-like components, for example with nonionic surfactants, are used as a granular compound.

19. The method according to any one of claims 16 to 18, characterized in that at least 2 pulverulent to granular compounds are produced before the pressing, the first of which the total amount of the anionic surfactants and the second of 75 to 100% by weight. contains the total amount of nonionic surfactants.

20. The method according to any one of claims 16 to 19, characterized in that a tablet is produced from at least 2 layers, which may have different dissolution rates.

21. The method according to any one of claims 16 to 20, characterized in that a tablet is produced from at least 3 layers, at least one of the inner layers containing a peroxy bleach.

22. Washing process in which at least two tablets according to one of claims 1 to 15 with the same or different composition are used in a single washing cycle, a modular system comprising a basic detergent tablet and a water softening tablet and / or a bleaching tablet being preferred .

23. Washing process in which at least 1 tablet according to one of claims 1 to 15 is used in a washing process, the tablet being positioned on the laundry in the washing machine directly at the beginning of the washing process by means of a metering container ( be¬).