WO2000027984A1 - Detergent shaped bodies having an optimized shape - Google Patents

Abstract

Detergent tablets with improved mechanical stability and reduced disintegration periods enabling them to be integrated into the wash cycle from the detergent compartment in household washing machines. The inventive tablets can be obtained by pressing a pre-mixture that contains more than 10 wt. % surfactants to form detergent tablets that have a rectangular base surface.

Description

 "Shape-optimized detergent tablets'

The present invention relates to detergent tablets for washing textiles in washing machines. In particular, the present invention relates to detergent tablets for washing textiles in a household washing machine, which are usually referred to as detergent tablets.

Detergent tablets have been widely described in the prior art and have become firmly established as a nominative form for detergents and cleaning agents in addition to the usual powdery products, particularly in the machine dishwashing detergent segment. Machine dishwashing detergents have a number of differences from detergents for washing textiles. So they have extremely low surfactant contents (mostly well below 5 wt .-%) and have disintegration or N-dissolution times, which are adapted to the conditions in dishwashers, where they have to survive a pre-wash at a lower temperature in order to be during a main wash at temperatures of 55 to 70 ° C slowly dissolve. While machine dishwashing detergents in tablet form come into contact with large amounts of hot water, the conditions for textile detergents or textile washing machines are designed differently: Here cold water is washed into the machine, that the detergent is conveyed from the detergent dispenser into the machine, or put in the machine Detergent dissolves. In addition, the amounts of water are significantly lower, so that a small form "shaped body" can not be pressed so hard, so as not to increase the disintegration time or solubility too drastically. While in dishwasher detergent tablets hardness above 150 Ν are the rule, detergent tablets are allowed to ensure sufficient disintegration times, only hardness up to a maximum of 80 Ν.

In addition to the advantage of improved disintegration times, these low hardnesses have disadvantages in the production and handling of the tablets. Modern tableting machine NEN have an output of up to 1000 molded articles per minute, which then have to be braked laterally and / or frontally and fed to a packaging unit. The tablets must not break or rub under mechanical stress, which is a greater technical problem for detergent tablets because of their lower hardness than for detergent tablets. Detergent tablets for machine dishwashing, but also water softening tablets, are mainly available in the market in round or rectangular form, the former, the flat cylinder, being of little importance compared to the second, the orthorhombus. The rectangular base of these moldings is due to the technical necessity that the moldings have to fit into the dosing chambers of the dishwashers, which open after the prewash cycle. Since these chambers are rectangular in shape, rectangular shaped bodies fit better into them. In the field of detergent tablets for textile laundry, however, shaped bodies with a rectangular base are unknown. Only round detergent tablets are available on the market.

The present invention was based on the object of providing detergent tablets and a process for their production which can withstand the mechanical loads in the manufacturing process better than the previously known tablets. In particular, the shaped bodies should have the greatest possible variability in terms of their composition, in order not to have to replace formulation constituents of the detergent by tabletting additives useless in the washing process. The moldings should have high hardness and short disintegration times and disintegrate into their secondary particles so quickly that they can be washed in via the dispensing chamber of household washing machines.

The present invention relates to detergent tablets made of compressed particulate detergent which contain more than 10% by weight of surfactants and have a rectangular base area.

While - as mentioned above - the rectangular shape of the base of the shaped body has established itself on the low-tenside detergent tablets due to the dimensions of the induction compartments, detergent tablets have only been pressed in a round shape due to aesthetic considerations. The detergent tablets of the Compared to round shaped bodies with identical compositions, the present invention now have improved strengths, which is manifested in the higher mechanical strength of the shaped bodies in the packaging line of the manufacturing process. If the tablets, which are rectangular according to the invention, are subjected to a force on one of their side surfaces, they withstand a higher load than shaped bodies with a round base surface which are subjected to a force along their radius.

In the context of the present invention, the term “shaped body with a rectangular base area” denotes detergent shaped body, the base area of which has four corners, each of which encloses an angle of 90 °, as a result of which opposite sides of the rectangle have the same length. If the length and width of the base are chosen so that they are the same (square base), the result is a tetragonal detergent tablet, which is pressed to a height that corresponds to the length of the square base , so you get a cubic detergent shaped body.

For aesthetic reasons, it is possible within the scope of the present invention to round off the corners of the detergent tablets according to the invention. A technical advantage of this procedure is the lower tendency to wear on the molded body edges. If shaped bodies with rounded corners are produced, the length and width of the shaped body base area do not change, but rather are still measured as the distance between the parallel sides of the shaped body. In preferred detergent tablets, the base area of the tablets corresponds to that of a rectangle with rounded edges, the radius of the round corner being 0.1 to 0.3 times, preferably 0.15 to 0.28 times, and in particular 0, Makes up 2 to 0.25 times the length of the shorter side of the rectangle.

If, for example, a molded body is provided which has a rectangular base area of 30 by 40 mm, the radius of the rounded corner in preferred detergent molded bodies is 3 to 9, preferably 4.5 to 8.4 and in particular 6 to 7.5 mm. As already mentioned above, shaped bodies with a square base area can be produced according to the invention, as can shaped bodies in which the length and width of the base area differ considerably from one another. In the context of the present invention, however, detergent molded articles are preferred in which the ratio of length to width of the molded article base area is in the range from 5: 1 to 1: 1, preferably in the range from 4: 1 to 1.05: 1 and in particular from 2: 1 to 1.1: 1.

The height to which the molded bodies according to the invention are pressed can also vary, as mentioned above. Detergent molded articles are preferred in which the ratio of the molded article height to the length of the shorter rectangular side of the molded article base area is in the range from 1: 1 to 1: 2.5, preferably in the range from 1: 1.05 to 1: 2 and in particular from 1.1: 1 to 1: 1.5.

Detergent tablets according to the invention have surfactant contents which are above 10% by weight, based on the tablet weight. The surfactants they contain come from the group of anionic, nonionic, cationic and / or zwitterionic surfactants, mixtures of anionic and nonionic surfactants being preferred from an application point of view. In general, detergent tablets which contain anionic and / or nonionic surfactants and total surfactant contents of at least 12.5% by weight, preferably at least 15% by weight and in particular at least 20% by weight, are preferred in the context of the present invention on the molded body weight.

Anionic surfactants used are, for example, those of the sulfonate and sulfate type. Preferred surfactants of the sulfonate type are C 1 -C ₃ -alkylbenzenesulfonates, olefin sulfonates, ie mixtures of alkene and hydroxyalkanesulfonates and disulfonates such as are obtained, for example, from C 1 -C _! Monoolefιnen with terminal or internal double bond by sulfonation with gaseous sulfur trioxide and subsequent alkaline or acidic hydrolysis of the sulfonation products into consideration. Also suitable are alkanesulfonates obtained from C 1 -C ₈ -alkanes, for example by sulfochlorination or sulfoxidation with subsequent hydrolysis or neutralization. Likewise, the esters of α-sulfofatty acids (ester sulfonates), for example the α-sulfonated methyl esters of hydrogenated coconut, palm kernel or tallow fatty acids are suitable.

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 of a monoglycerol with 1 to 3 moles of fatty acid or in the transesterification of triglycerides with 0.3 to 2 moles of glycerol become. Preferred sulfated fatty acid glycerol esters are the sulfate 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.

As alk (en) yl sulfates, the alkali and in particular the sodium salts of the sulfuric acid half esters of the C] ₂ -C] ₈ fatty alcohols, for example from coconut oil alcohol, tallow fatty alcohol, lauryl, myristyl, cetyl or stearyl alcohol or the Cιo-C ₂ o -Oxo alcohols and those half esters of secondary alcohols of this chain length are preferred. 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. The C ₂ -C ₆ alkyl sulfates and C ₁₂ - cis alkyl sulfates and Cj ₄ -C ₅ alkyl sulfates are preferred for washing technology reasons. In addition, 2,3-alkyl sulfates, which are produced for example in accordance with US Patent No. 3,234,258 or 5,075,041 and can be obtained as commercial products from Shell Oil Company under the name DAN ^®, are suitable anionic surfactants.

The sulfuric acid monoesters of the straight-chain or branched C _7-21 alcohols ethoxylated with 1 to 6 mol ethylene oxide, such as 2-methyl-branched C ₉ n alcohols with an average of 3.5 mol ethylene oxide (EO) or Cι -ι ₈ - Fatty alcohols with 1 to 4 EO are suitable. Because of their high foaming behavior, they are used in cleaning agents only in relatively small amounts, for example in amounts of 1 to 5% by weight.

Other suitable anionic surfactants are also the salts of alkylsulfosuccinic acid, which are also known as sulfosuccinates or as sulfosuccinic acid esters, and the monoesters and / or diesters of sulfosuccinic acid with alcohols, preferably fatty alcohols and in particular ethoxylated fatty alcohols. Preferred sulfosuccinates contain C _8- ι ₈ 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.

Soaps are particularly suitable as further anionic surfactants. Saturated fatty acid soaps are suitable, such as the salts of lauric acid, myristic acid, palmitic acid, stearic acid, hydrogenated erucic acid and behenic acid, and in particular from natural fatty acids, e.g. Coconut, palm kernel or tallow fatty acids, derived soap mixtures.

The anionic surfactants, including the soaps, can be in the form of their sodium, potassium or ammonium salts and also 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 (EO) per mole of alcohol, in which the alcohol radical has a linear or preferably 2-methyl branching 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 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 1 - ₂ -alcohols with 3 EO or 4 EO, C ₉ - alcohol with 7 EO, C ₃ - ₅ alcohols with 3 EO, 5 EO, 7 EO or 8 EO, C _12th ι ₈ - alcohols with 3 EO, 5 EO or 7 EO and mixtures of these, such as mixtures of Cι _2- ι ₄ alcohol with 3 EO and Cι _2- ι ₈ - alcohol with 5 EO. The specified ethoxy The degrees of lation represent statistical averages, which can be a whole 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 can also be used. Examples of this are 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.

Another class of preferably used nonionic surfactants, which are used either as the sole nonionic surfactant or in combination with other nonionic surfactants, are alkoxylated, preferably ethoxylated or ethoxylated and propoxylated fatty acid alkyl esters, preferably with 1 to 4 carbon atoms in the alkyl chain, in particular Fatty acid methyl esters as described, for example, in Japanese patent application JP 58/217598 or which are preferably prepared by the process described in international patent application WO-A-90/13533.

Nonionic surfactants of the amine oxide type, for example N-coconut alkyl-N, N-dimethylamine oxide and N-tallow alkyl-N, N-dihydroxyethylamine oxide, and the fatty acid alkanolamides can also be suitable. The amount of these nonionic 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), R ^J

R-CO-N- [Z] (I)

in which RCO stands for an aliphatic acyl radical with 6 to 22 carbon atoms, R ¹ 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. The polyhydroxy fatty acid amides are known substances which can usually be obtained by reductive amination of a reducing sugar with ammonia, an alkylamine or an alkanolamine and subsequent acylation with a fatty acid, a fatty acid alkyl ester or a fatty acid chloride.

The group of polyhydroxy fatty acid amides also includes compounds of the formula (II)

R ^! -OR ^2nd

R-CO-N- [Z] (II)

in which R represents a linear or branched alkyl or alkenyl radical having 7 to 12 carbon atoms, R ^{1 represents} a linear, branched or cyclic alkyl radical or an aryl radical having 2 to 8 carbon atoms and R represents a linear, branched or cyclic alkyl radical or Aryl radical or an oxy-alkyl radical with 1 to 8 carbon atoms, Cι _-4 - alkyl or phenyl radicals are preferred and [Z] stands for a linear polyhydroxyalkyl radical whose alkyl chain is substituted with at least two hydroxyl groups, or alkoxylated, preferably ethoxylated or propoxylated Derivatives of this rest.

[Z] is preferably obtained by reductive amination of a reduced sugar, for example glucose, fructose, maltose, lactose, galactose, mannose or xylose. The N-alkoxy- or N-aryloxy-substituted compounds can then, for example, according to the teaching of international application WO-A-95/07331, by reaction with fatty acids. remefylesters in the presence of an alkoxide as catalyst can be converted into the desired polyhydroxy fatty acid amides.

In the context of the present invention, detergent tablets are preferred which contain anionic (s) and nonionic (s) surfactant (s), with application technology advantages being able to result from certain quantitative ratios in which the individual classes of surfactants are used.

For example, detergent tablets are particularly preferred in which the ratio of anionic surfactant (s) to nonionic surfactant (s) is between 10: 1 and 1:10, preferably between 7.5: 1 and 1: 5 and in particular between 5: 1 and 1: 2 is.

Since detergent tablets according to the invention can also be formulated in multiple phases, for example in multiple layers, it can be advantageous from an application point of view if certain classes of surfactants in some phases of the detergent tablets or in the entire molded article, i.e. in all phases, are not included. A further important embodiment of the present invention therefore provides that at least one phase of the molded article is free from nonionic surfactants.

Conversely, the content of individual phases or of the entire molded body, i.e. all phases, certain surfactants have a positive effect. The introduction of the alkyl polyglycosides described above has proven to be advantageous, so that detergent tablets are preferred in which at least one phase of the tablets contains alkyl polyglycosides.

Similar to the nonionic surfactants, the omission of anionic surfactants from individual or all phases can result in detergent tablets which are more suitable for certain areas of application. It is therefore also conceivable within the scope of the present invention for detergent tablets to be made in which at least one phase of the tablet is free from anionic surfactants. Surfactants from the groups of the cationic and / or zwitterionic or amphoteric surfactants can be used as further surfactants in the detergent tablets according to the invention.

In addition to the surfactants, builders are the most important ingredients in detergent tablets. The detergent tablets according to the invention can contain all of the builders customarily used in detergents and cleaning agents, in particular thus zeolites, silicates, carbonates, organic cobuilders and, where there are no ecological prejudices against their use, also the phosphates. Detergent tablets preferred in the context of the present invention additionally contain one or more builders, preferably from the group of silicates and aluminosilicates, in amounts of 10 to 40% by weight, preferably 15 to 35% by weight and in particular 20 to 30% by weight .-%, each based on the molded body weight.

Suitable crystalline, layered sodium silicates have the general formula NaMSiχO _{x +} ι 'HO, 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 are. Such crystalline layered silicates are described, for example, in European patent application EP-A-0 164 514. Preferred crystalline layered silicates of the formula given are those in which M represents sodium and x assumes the values 2 or 3. In particular, both β- and δ-sodium disilicate Na Si ₂ O ₅ 'yH O are preferred, wherein β-sodium disilicate can be obtained, for example, by the method described in international patent application WO-A-91/08171.

Amorphous sodium silicates with a module Na ₂ O: SiO from 1: 2 to 1: 3.3, preferably from 1: 2 to 1: 2.8 and in particular from 1: 2 to 1: 2.6, which delay the dissolution, can also be used are and have secondary washing properties. The delay in dissolution compared to conventional amorphous sodium silicates can be caused in various ways, for example by surface treatment, compounding, compacting / compression or by overdrying. In the context of this invention, the term "amoφh" is also understood to mean "roentgenamoφh". This means that the silicates do not give sharp X-ray reflections in X-ray diffraction experiments as they do for crystalline ne substances are typical, but at most one or more maxima of the scattered X-rays, which have a width of several degree units of the diffraction angle. However, it can very well lead to particularly good builder properties if the silicate particles deliver washed-out or even sharp diffraction maxima in electron diffraction experiments. This is to be integrated in such a way that the products have microcrystalline areas of size 10 to a few hundred nm, values up to max. 50 nm and in particular up to max. 20 nm are preferred. Such so-called X-ray amorphous silicates, which also have a delay in dissolution compared to conventional water glasses, are described, for example, in German patent application DE-A-44 00 024. Particularly preferred are compressed / compacted amorphous silicates, compounded amorphous silicates and over-dried X-ray silicates.

The finely crystalline, synthetic and bound water-containing zeolite used is preferably zeolite A and / or P. As zeolite P, zeolite ^MAP® (commercial product from Crosfield) is particularly preferred. However, zeolite X and mixtures of A, X and / or P are also suitable. Commercially available and can preferably be used in the context of the present invention, for example a co-crystallizate of zeolite X and zeolite A (about 80% by weight of zeolite X) ), which is sold by CONDEA Augusta SpA under the brand name VEGOBOND AX ^® and by the formula

nNa ₂ O ^• (ln) K ₂ O ^• Al ₂ O ₃ ^■ (2 - 2.5) SiO ₂ ^■ (3.5 - 5.5) H ₂ O

can be described. The zeolite can be used both as a builder in a granular compound and can also be used for a kind of "powdering" of the entire mixture to be used, usually both ways of incohering the zeolite into the premix. Suitable zeolites have an average particle size of less than 10 μm (volume distribution; measurement method: Coulter Counter) and preferably contain 18 to 22% by weight, in particular 20 to 22% by weight, of bound water.

It is of course also possible to use the generally known phosphates as builder substances, provided that such use is not avoided for ecological reasons should be. The sodium salts of orthophosphates, pyrophosphates and in particular tripolyphosphates are particularly suitable.

The amount of builder is usually between 10 and 70% by weight, preferably between 15 and 60% by weight and in particular between 20 and 50% by weight. Again, the amount of builders used depends on the intended use, so that bleach tablets can have higher amounts of builders (for example between 20 and 70% by weight, preferably between 25 and 65% by weight and in particular between 30 and 55% by weight) ), for example detergent tablets (usually 10 to 50% by weight, preferably 12.5 to 45% by weight and in particular between 17.5 and 37.5% by weight).

Usable organic builders are, for example, the polycarboxylic acids that can be used in the form of their sodium salts, such as citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids, aminocarboxylic acids, nitrilotriacetic acid (NTA), as long as such use is not objectionable for ecological reasons, and mixtures of these. Preferred salts are the salts of polycarboxylic acids such as citric acid, adipic acid, succinic acid, glutaric acid, tartaric acid, sugar acids and mixtures of these.

If universal detergents are to be produced within the scope of the present invention, the use of bleaching agents in the detergent tablets according to the invention is recommended. 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 usable bleaching agents are, for example, sodium percarbonate, peroxypyrophosphates, citrate perhydrates and H ₂ O-providing peracidic salts or peracids, such as perbenzoates, peroxophthalates, diperazelaic acid, phthaloiminoperacid or diperdodecanedioic acid. Even when using the bleaching agents, it is possible to dispense with the use of surfactants and / or builders, so that pure bleach tablets can be produced. Typical organic bleaching agents are the diacyl peroxides, such as dibenzoyl peroxide. Other typical organic bleaching agents are peroxy acids, examples of which include alkyl peroxy acids and aryl peroxy acids. Preferred representatives are (a) the peroxybenzoic acid and its ring-substituted derivatives, such as alkyl peroxybenzoic acids, but also peroxy-α-naphthoic acid and magnesium monophthalate, (b) the aliphatic or substituted aliphatic peroxyacids, such as peroxylauric acid, peroxystearic acid, ε-phoperoxymoxyhexanoic acid [ε-phoperoxymoxyhexanoic acid], ε-phoperoximoxyhexanoic acid and ε-phoperoxymoxyhexanoic acid [alpha] -phoperoxyimidoxanoic acid (PAP)], o-carboxybenzamidoperoxycaproic acid, N-nonenylamidoperadipic acid and N-nonenylamidopersuccinate, and (c) aliphatic and araliphatic peroxydicarboxylic acids, such as 1,12-diperoxycarboxylic acid, 1, 9-diperoxyazelaic acid, diperocyseboxydiacid acid, diperoxyacyldiperoxyacid, Decyldiperoxybutane-1,4-diacid, N, N-terephthaloyl-di (6-aminopercapronic acid) can be used.

Detergent tablets preferred in the context of the present invention additionally contain one or more bleaches, preferably from the group of peroxy bleaches, with particular preference for one or more substances from the group of sodium perborate monohydrate, sodium perborate tetrahydrate and sodium percarbonate, in amounts of 5 to 30% by weight. -%, preferably from 10 to 25 wt .-% and in particular from 15 to 20 wt .-%, each based on the molded body weight.

In order to facilitate the disintegration of highly compressed moldings, it is possible to incorporate disintegration aids, so-called tablet disintegrants, in order to shorten the disintegration times. According to Römpp (9th edition, vol. 6, p. 4440) and Voigt "Textbook of pharmaceutical technology" (6th edition, 1987, p. 182-184), tablet disintegrants or accelerators of decay are understood as auxiliary substances which are necessary for rapid disintegration of tablets in water or gastric juice and ensure the release of the pharmaceuticals in absorbable form.

These substances, which are also referred to as "explosives" due to their effect, increase their volume when water enters, whereby on the one hand the intrinsic volume increases (swelling) and on the other hand a pressure can be generated by the release of gases, which breaks the tablet into smaller particles disintegrates. Well-known disintegration support Medium are, for example, carbonate / citric acid systems, although other organic acids can also be used. Swelling disintegration aids are, for example, synthetic polymers such as polyvinylpyrrolidone (PVP) or natural polymers or modified natural products such as cellulose and starch and their derivatives, alginates or casein derivatives.

Preferred detergent tablets contain 0.5 to 10% by weight, preferably 3 to 7% by weight and in particular 4 to 6% by weight of one or more disintegration auxiliaries, in each case based on the molded article weight.

Disintegrants based on cellulose are used as preferred disintegrants in the context of the present invention, so that preferred washing and cleaning agent shaped bodies such a disintegrant based on cellulose in amounts of 0.5 to 10% by weight, preferably 3 to 7% by weight and in particular 4 contain up to 6 wt .-%. Pure cellulose has the formal gross composition (C ₆ HιoO ₅ ) _n and, formally speaking, is a ß-1,4-polyacetal of cellobiose, which in turn is made up of two molecules of glucose. Suitable celluloses consist of approximately 500 to 5000 glucose units and consequently have average molecular weights of 50,000 to 500,000. Cellulose-based disintegrants which can be used in the context of the present invention are also cellulose derivatives which can be obtained from cellulose by polymer-analogous reactions. Such chemically modified celluloses include, for example, products from esterifications or etherifications in which hydroxyl hydrogen atoms have been substituted. However, celluloses in which the hydroxyl groups have been replaced by functional groups which are not bound via an oxygen atom can also be used as cellulose derivatives. The group of cellulose derivatives includes, for example, alkali celluloses, carboxymethyl cellulose (CMC), cellulose esters and ethers and aminocelluloses. The cellulose derivatives mentioned are preferably not used alone as a cellulose-based disintegrant, but are used in a mixture with cellulose. The content of cellulose derivatives in these mixtures is preferably below 50% by weight, particularly preferably below 20% by weight, based on the cellulose-based disintegrant. Is particularly preferred as Cellulose-based disintegrant used pure cellulose that is free of cellulose derivatives.

The cellulose used as disintegration aid is preferably not used in finely divided form, but is converted into a coarser form, for example granulated or compacted, before being added to the premixes to be treated. Detergent tablets containing disintegrants in granular or optionally granulated form are described in German patent applications DE 197 09 991 (Stefan Herzog) and DE 197 10 254 (Henkel) and international patent application O98 / 40463 (Henkel). These documents can also be found in more detail on the production of granulated, compacted or cogranulated cellulose disintegrants. The particle sizes of such disintegrants are usually above 200 μm, preferably at least 90% by weight between 300 and 1600 μm and in particular at least 90% by weight between 400 and 1200 μm. The above and described in more detail in the documents cited coarser disintegration aids, are preferred as disintegration aids and are commercially available, for example under the name of Arbocel ^® TF-30-HG from Rettenmaier available in the present invention.

Microcrystalline cellulose can be used as a further cellulose-based disintegrant or as a component of this component. This microcrystalline cellulose is obtained by partial hydrolysis of celluloses under conditions which only attack and completely dissolve the amorphous areas (approx. 30% of the total cellulose mass) of the celluloses, but leave the crystalline areas (approx. 70%) undamaged. A subsequent disaggregation of the microfine celluloses resulting from the hydrolysis provides the microcrystalline celluloses, which have primary particle sizes of approximately 5 μm and can be compacted, for example, to granules with an average particle size of 200 μm.

Detergent tablets preferred in the context of the present invention additionally contain a disintegration aid, preferably a cellulose-based disintegration aid, preferably in granular, cogranulated or compacted form, in Amounts of 0.5 to 10 wt .-%, preferably from 3 to 7 wt .-% and in particular from 4 to 6 wt .-%, each based on the molded body weight.

The rectangular detergent tablets according to the invention with surfactant contents above 10% by weight, based on the weight of the molded article, can contain further conventional detergent ingredients, in particular bleach activators, enzymes, polymers, foam inhibitors, graying inhibitors, colorants and fragrances.

In order to achieve an improved bleaching effect when washing or cleaning at temperatures of 60 ° C and below, bleach activators can be incorporated. Bleach activators which can be used are compounds which, under perhydrolysis conditions, give aliphatic peroxocarboxylic acids having preferably 1 to 10 C atoms, in particular 2 to 4 C atoms, and / or optionally substituted perbenzoic acid. Suitable substances are those which carry O- and / or N-acyl groups of the number of carbon atoms mentioned and / or optionally substituted benzoyl groups. Preferred are multiply acylated alkylenediamines, in particular tetraacetylethylenediamine (TAED), acylated triazine derivatives, in particular 1,5-diacetyl-2,4-dioxohexahydro-1,3,5-triazine (DADHT), acylated glycolurils, in particular tetraacetylglycoluril (TAGU), N-acylimides, especially N-nonanoylsuccinimide (NOSI), acylated phenol sulfonates, especially n-nonanoyl- or isononanoyloxybenzenesulfonate (n- or iso-NOBS), carboxylic acid anhydrides, especially phthalic anhydride, acylated polyhydric alcohols and especially triacetyl, especially triacetin, 5-diacetoxy-2,5-dihydrofuran.

In addition to the conventional bleach activators or in their place, so-called bleach catalysts can also be incorporated into the moldings. These substances are bleach-enhancing transition metal salts or transition metal complexes such as, for example, Mn, Fe, Co, Ru or Mo salt complexes or carbonyl complexes. Mn, Fe, Co, Ru, Mo, Ti, V and Cu complexes with N-containing tripod ligands as well as Co, Fe, Cu and Ru amine complexes can also be used as bleaching catalysts.

Suitable enzymes are those from the class of proteases, lipases, amylases, cellulases or mixtures thereof. Bacterial strains or are particularly well suited Fungi such as Bacillus subtilis, Bacillus licheniformis and Streptomyces griseus are enzymatic active ingredients. Proteases of the subtilisin type and in particular proteases which are obtained from Bacillus lentus are preferably used. Enzyme mixtures, for example of protease and amylase 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, are of particular interest. Peroxidases or oxidases have also proven to be suitable in some cases. The enzymes can be adsorbed on carriers and / or embedded in coating substances in order to protect them against premature decomposition. The proportion of enzymes, enzyme mixtures or enzyme granules in the shaped bodies according to the invention can be, for example, about 0.1 to 5% by weight, preferably 0.1 to about 2% by weight.

In addition, the detergent tablets may also contain components that have a positive influence on the washability of oil and fat from textiles (so-called soil repellents). This effect becomes particularly clear when a textile is soiled that 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 cellulose and methyl hydroxypropyl cellulose with a proportion of methoxyl groups from 15 to 30% by weight and of hydroxypropoxyl groups from 1 to 15% by weight, based in each case on the nonionic cellulose ether, and the polymers of phthalic acid and / or terephthalic acid or their derivatives known from the prior art, in particular polymers of ethylene terephthalates and / or polyethylene glycol terephthalates or anionically and / or nonionically modified derivatives thereof. Of these, the sulfonated derivatives of phthalic acid and terephthalic acid polymers are particularly preferred.

The shaped bodies can contain derivatives of diaminostilbenedisulfonic acid or their alkali metal salts as optical brighteners. Suitable are, for example, salts of 4,4'-bis (2-anilino-4-moφholino-l, 3,5-triazinyl-6-amino) stilbene-2,2'-disulfonic acid or compounds of similar structure which instead of the Moφholino- Group carry 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, or 4- (4-chlorostyryl) -4 '- (2-sulfostyryl) diphenyl. Mixtures of the aforementioned brighteners can also be used.

Colorants and fragrances are added to the detergent tablets according to the invention in order to improve the aesthetic impression of the products and, in addition to the softness, to provide the consumer with a visually and sensorially "typical and unmistakable" product. As perfume oils or fragrances, individual fragrance compounds, e.g. the synthetic products of the ester, ether, aldehyde, ketone, alcohol and hydrocarbon type are used. Fragrance compounds of the ester type are e.g. Benzyl acetate, phenoxyethyl isobutyrate, p-tert-butylcyclohexyl acetate, linalyl acetate, dimethylbenzylcarbinyl acetate, phenylethyl acetate, linalylbenzoate, benzyl formate, ethylmethylphenylglycinate, allylcyclohexylpropionate, styrallyl propylate and benzyl acetate. The ethers include, for example, benzyl ethyl ether, the aldehydes e.g. the linear alkanals with 8-18 C atoms, citral, citronellal, citronellyloxyacetaldehyd, cyclamenaldehyde, hydroxycitronellal, lilial and bourgeonal, to the ketones e.g. the Jonone, c-isomethyl ionone and methyl-cedryl ketone, to the alcohols anethole, citronellol, eugenol, geraniol, linalool, phenylethyl alcohol and Teφineol, to the hydrocarbons belong mainly the Teφene like limonene and pinene. However, preference is given to using mixtures of different fragrances which together produce an appealing fragrance. Such perfume oils can also contain natural fragrance mixtures as are available from plant sources, e.g. Pine, citrus, jasmine, patchouly, rose or ylang-ylang oil. Also suitable are muscatel, sage oil, chamomile oil, clove oil, lemon balm oil, mint oil, cinnamon leaf oil, linden blossom oil, juniper berry oil, vetiver oil, olibanum oil, galbanum oil and labdanum oil as well as orange blossom oil, neroliol, orange peel oil and sandalwood oil.

The colorant content of the detergent tablets according to the invention is usually less than 0.01% by weight, while fragrances can make up up to 2% by weight of the entire formulation. The fragrances can be incorporated directly into the agents according to the invention, but it can also be advantageous to apply the fragrances to carriers which increase the adhesion of the perfume to the laundry and ensure a long-lasting fragrance of the textiles by slower fragrance release. Cyclodextrins, for example, have proven useful as such carrier materials, and the cyclodextrin-perfume complexes can additionally be coated with further auxiliaries.

In order to improve the aesthetic impression of the agents according to the invention, they can be colored with suitable dyes. Preferred dyes, the selection of which is not difficult for the person skilled in the art, have a high storage stability and insensitivity to the other ingredients of the compositions and to light, and no pronounced substantivity to textile fibers, in order not to dye them.

The production of wash-active molded bodies is done by applying pressure to a mixture to be veφress, which is located in the cavity of a press. In the simplest case of molded article production, which is referred to simply as tableting below, the mixture to be tabletted is pressed directly, ie without prior granulation. The advantages of this so-called direct tableting are its simple and inexpensive application, since no further process steps and consequently no further plants are required. However, these advantages are offset by disadvantages. For example, a powder mixture that is to be tabletted directly must have sufficient plastic deformability and have good flow properties; furthermore, it must not show any tendency to segregate during storage, transport and filling of the die. These three requirements are extremely difficult to master with many substance mixtures, so that direct tableting is not often used, particularly in the production of detergent tablets. The usual way of producing detergent tablets is therefore based on powdery components (“primary particles”) which are agglomerated or granulated by suitable processes to form secondary particles with a larger particle diameter. These granules or mixtures of different granules are then mixed with individual powdery additives and fed to the tableting. Another object of the present invention is therefore a method for producing detergent tablets with a surfactant content of more than 10 wt .-%, based on the molded article, in which a particulate premix with a surfactant content of more than 10 wt .-%, based on the premix is pressed in a press, the pressing tools of which have a rectangular base.

Detergent tablets are usually first produced by dry mixing the components, which can be wholly or partially pre-granulated, and then providing information, in particular feeding them to tablets, whereby conventional methods can be used. To produce the detergent tablets, the premix is compacted in a so-called die between two stamps to form a solid compact. This process, which is briefly referred to as tableting in the following, is divided into four sections: metering, compression (elastic deformation), plastic deformation and ejection.

First, the premix is introduced into the die, the filling quantity and thus the weight and the shape of the molded body being formed being determined by the position of the lower punch and the shape of the pressing tool. The constant dosing, even at high mold throughputs, is preferably achieved by volumetric dosing of the premix. As the tableting continues, the upper punch touches the premix and lowers further in the direction of the lower punch. During this compression, the particles of the premix are pressed closer together, the void volume within the filling between the punches continuously decreasing. From a certain position of the upper punch (and thus from a certain pressure on the premix), the plastic deformation begins, in which the particles flow together and the molded body is formed. Depending on the physical properties of the premix, some of the premix particles are also crushed and sintering of the premix occurs at even higher pressures. With increasing pressing speed, that is to say high throughput quantities, the phase of elastic deformation is shortened further and further, so that the resulting shaped bodies can have more or less large cavities. In the last step of tableting, the finished molded body is pressed out of the die by the lower punch and through subsequent transport devices transported away. At this point in time, only the weight of the molded body is finally determined, since the compacts can still change their shape and size due to physical processes (stretching, crystallographic effects, cooling, etc.).

Tableting takes place in commercially available tablet presses, which can in principle be equipped with single or double punches. In the latter case, not only is the upper stamp used to build up pressure, the lower stamp also moves towards the upper stamp during the pressing process, while the upper stamp presses down. For small production quantities, eccentric tablet presses are preferably used, in which the punch or stamps are fastened to an eccentric disc, which in turn is mounted on an axis with a certain rotational speed. The movement of these rams is comparable to that of a conventional four-stroke engine. The pressing can take place with one upper and one lower punch, but several punches can also be attached to one eccentric disk, the number of die holes being increased accordingly. The throughputs of eccentric presses vary depending on the type from a few hundred to a maximum of 3000 tablets per hour.

For larger throughputs, rotary tablet presses are selected in which a larger number of dies is arranged in a circle on a so-called die table. The number of matrices varies between 6 and 55 depending on the model, although larger matrices are also commercially available. Each die on the die table is assigned an upper and lower punch, and again the pressure can be built up actively only by the upper or lower punch, but also by both stamps. The die table and the stamps move about a common vertical axis, the stamps being brought into the positions for filling, compaction, plastic deformation and ejection by means of rail-like cam tracks during the rotation. Wherever a particularly serious lifting or lowering of the punches is required (filling, compacting, ejecting), these cam tracks are supported by additional low-pressure pieces, low-tension rails and lifting tracks. The die is filled via a rigidly arranged feed device, the so-called filling shoe, which is connected to a storage container for the premix. The press pressure on the premix can be individually adjusted via the press paths for the upper and lower punches, the pressure being built up by rolling the punch shaft heads past adjustable pressure rollers.

Rotary presses can also be provided with two filling shoes to increase the throughput, with only a semicircle having to be run through to produce a tablet. For the production of two-layer and multi-layer molded bodies, several filling shoes are arranged one behind the other without the slightly pressed first layer being ejected before further filling. With suitable process control, jacket and dot tablets can also be produced in this way, which have an onion-shell-like structure, the top side of the core or the core layers not being covered in the case of the dot tablets and thus remaining visible. Rotary tablet presses can also be equipped with single or multiple tools, so that, for example, an outer circle with 50 and an inner circle with 35 holes can be used simultaneously for pressing. The throughputs of modern rotary tablet presses are over one million molded articles per hour.

Tableting machines suitable within the scope of the present invention are available, for example, from the companies Apparatebau Holzwarth GbR, Asperg, Wilhelm Fette GmbH, Schwarzenbek, Hofer GmbH, Weil, KILIAN, Cologne, KOMAGE, Kell am See, KORSCH Pressen GmbH, Berlin, Mapag Maschinenbau AG, Bern (CH) and Courtoy NV, Halle (BE / LU). For example, the hydraulic double pressure press HPF 630 from LAEIS, D. is particularly suitable.

In the method according to the invention, the pressing tools have a rectangular base area. Since the pressing tools are positively immersed in the die or limit it if they are not moved, the die hole of the tablet press in the method according to the invention also has a rectangular cross section (horizontal section). If changes are made to the base surface of a pressing tool, these are to be carried out analogously both on the die and on the opposite pressing tool. In the method according to the invention, too, the configurations of the pressing tool and die referred to above as preferred which apply to the advantageous forms of detergent tablets. Methods according to the invention are preferred in which the base area of the pressing tools corresponds to that of a rectangle with rounded edges, the radius of the round corner being 0.1 to 0.3 times, preferably 0.15 to 0.28 times and in particular 0.2 to 0.25 times the length of the shorter side of the rectangle, press tools being preferred in which the ratio of length to width of the press surface is in the range from 5: 1 to 1: 1, preferably in the range from 4: 1 to 1.05: 1 and in particular from 2: 1 to 1.1: 1.

As mentioned at the beginning, rectangular detergent tablets have so far not been commercially available and the advantages in their handling are not described in the prior art. The present invention therefore furthermore relates to the use of detergent tablets with surfactant contents above 10% by weight for cleaning textiles in a washing machine.

The present invention allows the production and safe packaging of detergent tablets; which are characterized by short disintegration times. Shatter-resistant molded bodies can be obtained here by lower compression pressures, as can only be achieved with round detergent tablets by higher compression pressures. Due to the reduced pressure, the disintegration times can be reduced to such an extent that the detergent tablets can be dosed easily and without residues via the dispenser. A preferred embodiment is therefore the use, which is characterized in that the detergent tablets are dosed via the dispenser of a household washing machine.

Examples:

Granulation in a 50-liter ploughshare mixer from Lödige produced granules containing tensides (for composition, see Table 1), which was used as the basis for a particulate premix. Following the granulation, the granules were dried in a fluidized bed apparatus from Glatt at a supply air temperature of 60 ° C. over a period of 30 minutes. After drying, fine particles <0.4 mm and coarse particles> 1.6 mm were screened off.

A premix was produced by mixing the surfactant-containing granules with bleach, bleach activator and other preparation components, after which the premixes were compressed into tablets in a Korsch eccentric press (see below). The composition of the premixes to be pressed (and thus the shaped body) is shown in Table 2.

Table 1: Composition of the surfactant granules [% by weight]

Tabelle 2: Zusammensetzung der Vorgemische [Gew.-%]:

Table 2: Composition of the premixes [% by weight]:

* compacted cellulose (particle size: 90% by weight> 400 μm)

The molded bodies E according to the invention were pressed in the form of a rectangle with rounded corners (length: 38 mm, width: 34 mm, radius in the corners: 8 mm), the molded bodies of comparative example V were circular (diameter: 44 mm). Both molded body series were shown the same weight (37.5 g), the molded body V having a height of 22 mm and the molded body E having a height of 26 mm.

In order to simulate the mechanical stress on the tablets in a packaging line, the tablets were pressed in a measuring apparatus (Schleuniger 6D) with plane-parallel jaws until they broke, the force acting on the jaws being determined. In the molded bodies according to the invention, the breaking strength was measured on both sides. According to experience from production, the tablets in this test must have a minimum hardness of 50 N in order to survive the packaging line at throughputs of 1000 pieces per minute without damage. The physical properties of the molded body are shown in Table 3: Table 3: physical properties of the molded body:

Force acts along the tablet width

** Force acts along the length of the tablet

*** Force acts along the tablet diameter

Table 3 clearly shows that the detergent tablets according to the invention have shorter disintegration times with the same tablet hardness. That disintegrate better despite the same mechanical strength. This is due to the fact that a lower compression pressure is sufficient in the molded bodies according to the invention in order to achieve the same mechanical stability as in the molded bodies of comparative example V.

Claims

Claims: 1. Detergent tablets made of compressed particulate detergent, containing more than 10% by weight of surfactants, characterized in that the tablets have a rectangular base. 2. Detergent molded article according to claim 1, characterized in that the base area of the molded article corresponds to that of a rectangle with rounded edges, the radius of the round corner being 0.1 to 0.3 times, preferably 0.15 to 0, 28 times and in particular 0.2 to 0.25 times the length of the shorter side of the rectangle. 3. Detergent molded article according to one of claims 1 or 2, characterized in that the ratio of length to width of the molded article base area is in the range from 5: 1 to 1: 1, preferably in the range from 4: 1 to 1.05: 1 and in particular from 2 : 1 to 1.1: 1. 4. Detergent molded article according to one of claims 1 to 3, characterized in that the ratio of the molded article height to the length of the shorter rectangular side of the molded article base area is in the range 1: 1 to 1: 2.5, preferably in the range of 1: 1.05 to 1: 2 and in particular from 1.1: 1 to 1: 1.5. 5. Detergent tablets according to one of claims 1 to 4, characterized in that they contain anionic and / or nonionic surfactants and total surfactant contents of at least 12.5% by weight, preferably at least 15% by weight and in particular at least 20% by weight. -%, each based on the molded body weight. 6. Detergent tablets according to one of claims 1 to 5, characterized in that they additionally contain one or more builders, preferably from the group of silicates and aluminosilicates, in amounts of 10 to 40% by weight, preferably 15 to 35% by weight. % and in particular from 20 to 30 wt .-%, each based on the molded body weight. 7. Detergent form according to one of claims 1 to 6, characterized in that it additionally one or more bleaching agents, preferably from the group of peroxy bleaching agents, with particular preference for one or more substances from the group sodium perborate monohydrate, sodium perborate tetrahydrate and sodium per- carbonate, in amounts of 5 to 30 wt .-%, preferably from 10 to 25 wt .-% and in particular from 15 to 20 wt .-%, each based on the molded body weight. 8. Detergent tablets according to one of claims 1 to 7, characterized in that they additionally contain a disintegration aid, preferably a cellulose-based disintegration aid, preferably in granular, cogranulated or compacted form, in amounts of 0.5 to 10% by weight, preferably of 3 to 7 wt .-% and in particular from 4 to 6 wt .-%, each based on the molded body weight, contain. 9. A process for the preparation of detergent tablets with a surfactant content of more than 10% by weight, based on the molded article, characterized in that a particulate premix with a surfactant content of more than 10% by weight, based on the premix, in one Press veφreßt, the pressing tools have a rectangular base. 10. The method according to claim 9, characterized in that the base of the pressing tools corresponds to that of a rectangle with rounded edges, the radius of the round corner being 0.1 to 0.3 times, preferably 0.15 to 0, 28 times and in particular 0.2 to 0.25 times the length of the shorter side of the rectangle, pressing tools are preferred in which the ratio of length to width of the pressing surface in the range 5: 1 to 1: 1, preferably in the range from 4: 1 to 1.05: 1 and in particular from 2: 1 to 1.1: 1. 11. Use of detergent tablets with surfactant contents above 10% by weight for cleaning textiles in a washing machine. 2. Use according to claim 11, characterized in that the laundry detergent tablets are dosed via the dispenser of a household washing machine.