GB2189255A - Detergent bar - Google Patents

Abstract

The detergent bar contains aluminium silicates such as zeolite A, and may be used for the washing of fabrics by hand and in rivers.

Description

SPECIFICATION A Detergent in Bar Form Detergent bars are used inter alia in the washing of fabrics by hand and in rivers.

G & S 2 127 426 describes detergent bars containing from 5 to 60% by weight washing-active substances, 0 to 60% by weight builders and acid-treated bentonite to increase their hardness. The builders used are water-soluble carbonates, organic compounds, such as sodium nitrilotriacetate for example, and above all water-soluble phosphates.

Known detergent bars based on linear, higher alkyl-benzene sulfonates and pentasodium tripolyphosphate as builder have long been recognized for their good detergent action, the linear higher alkylbenzene sulfonates being biologically degradable and showing an excellent detergent action while the polyphosphates are regarded in principle as good and safe builders for the detergent. However, since the phosphates have become less popular in recent years on account of the eutrophication of inland waters, attempts have been made to use numerous other phosphate substitutes having builder properties. For example, it was assumed that carbonates, silicates, borax, the trisodium salt mf nitrilo triacetic acid (NTA), organic sequestrants, polyelectrolyte, chelating agents and other products, would enhance the detergent effect of synthetic organic detergents.However, most of these phosphate substitutes have unfavorable properties even though they do not contribute to the eutrophication of inland waters to the same extent as the phosphates. Some of these phosphate substitutes are toxic, some are said to have carcinogenic properties, others are not stable in storage or impart undesirable flow properties to the end product or create processing problems while yet others have unpleasant odor or react with the other constituents of the detergent. Accordingly, there is considerable uncertainty as to which products, if any, may be regarded as suitable phosphate substitutes.

It was found quite recently that, despite their insolubility in water, zeolites, particularly certain synthetic, crystalline molecular sieve zeolites, preferably in at least partially hydrated form, are suitable ion exchangers for calcium ions and, accordingly, are capable of enhancing the detergency of synthetic, organic detergents, particularly anionic detergents, and may also be used in conjunction with nonionic detergents.

The present invention relates to a detergent bar which is characterized in that it contains aluminum silicate.

In one preferred embodiment, the detergent bar may have the following composition: from 5 to 50% by weight surfactants from 5 to 60% by weight aluminium silicate from 0 to 60% by weight filler and washing alkalis > 1% by weight additives from 0 to 8% by weight lubricants.

The aluminium silicates may be naturally occurring products or synthetic products, synthetic crystalline products being preferred. They may be prepared, for example, by reaction of water-soluble silicates with water-soluble aluminates in the presence of water. To this end, aqueous solutions of the starting materials may be mixed together or one component present in solid form may be reacted with the other component present in the form of an aqueous solution. The desired aluminium silicates may also be obtained by mixing both components present in solid form in the presence of water. Aluminium silicates may also be prepared from Al(OH)3, Awl203 or SiO2 by reaction with alkali silicate or alkali aluminate solutions. The aluminium silicates may also be prepared by other known methods.More particularly, the present invention relates to aluminium silicates having a three-dimensional space lattice structure.

The preferred calcium binding power of from 100 to 200 mg CaO/g active substance and generally from about 100 to 180 mg CaO/g active substance is found above all in compounds having the following composition: 0.7-1.1 Na2O Al2Oa 1.2-3.3 SiO2 This summation formula comprises two types of different crystal structures (or their non-crystalline precursors) which also differ in their summation formulae, namely: 1) 0.7-1.1 Na2O Al203 1.3-2.4Si02 2) 0.7-1.1 Na2O Al203 2.3.3 SiO2 The different crystal structures show up in X-ray diffractograms.

The crystalline aluminium silicate present in aqueous suspension may be separated off from the residual aqueous solution and dried. The product contains more or less bound water, depending on the drying conditions.

The particle size of the individual aluminium silicate particles may be different and may lie, for example, in the range of from 0.1 micrometer to 0.1 mm. These figures apply to the primary particle size, i.e. the size of the particles which accumulate during precipitation and, optionally, subsequent crystallization. It is of particular advantage to use aluminium silicates of which 80% by weight consist of particles from 10 to 0.01 micrometer in size and more especially from 8 to 0.1 micrometer in size.

These aluminium silicates preferably contain no primary or secondary particles largerthan 45 micrometers in diameter. Secondary particles are particles formed by agglomeration of the primary particles to relatively large structures.

In one particularly preferred embodiment of the invention, the aluminium silicate used is powder-form zeolite A having a particularly defined particle spectrum.

Zeolite powders such as these may be prepared in accordance with DE-AS 2447 021, DE-AS 25 17 218, DE-OS 26 52 419, DE-OS 26 51 420, DE-OS 26 51 436, DE-OS 26 51 437, DE-OS 26 51 445 or DE-OS 26 51 485. They then show the particle distribution curves indicated therein.

In one particularly preferred embodiment, a powder-form zeolite A having the particle size distribution described in DE-OS 26 51 485 is used as the aluminium silicate.

The surfactants may be anionic and/or nonionic surfactants. The anionic surfactants used include: - alkylbenzene sulfonate (ABS), preferably having a linear alkyl chain (LAS) containing from 8 to 22 carbon atoms, - paraffin sulfonates having a linear or branched C10-C20 and preferably C13-C17 chain (sulfonate group terminal or distributed over the chain), - sulfates of higher C8-C22 alcohols, for example lauryl alcohol, tallow fatty alcohol and coconut oil fatty alcohol, - ether sulfates of higher C8C22 alcohols, for example the same alcohol radicals as in the above mentioned sulfates of higher alcohols (the molar ratio of alkylene oxide, particularly ethylene oxide, to alcohol is from 1:1 to 5:1), - a-olefin sulfonates having a C8-C20 and preferably C13-C17 chain, - soaps, i.e. water-soluble salts of higher fatty acids.

- Suitable cations for the above-mentioned surfactants are sodium, potassium and ammonium or substituted ammonium ions, such as mono-, di- and triethanol and also tetramethyl ammonium.

The nonionic surfactants used include: - condensates of alkylene oxide (C2-C4), preferably ethylene oxide, propylene oxide, and a hydrocarbon radical (alkyl, alkylphenol, higher fatty alcohols, higher fatty acids, higher fatty amines), for example tallow fatty alcohol (C16-C18) containing about 5 to 30 ethylene oxide units, fatty acid amides formed from alkanolamine, preferably mono- and diethanolamine, and also isopropylamine and a fatty acid, for example coconut oil fatty acid monoethanolamide.

The following materials may be used as filters, preferably in a quantity of from 0 to 60% by weight: sulfates, carbonates and hydrogen carbonates of sodium, potassium, calcium, and magnesium. Other materials, such as bentonite and starch (potato starch, rice starch and wheat starch), are known from the literature.

Sodium carbonate and/or sodium silicate may be used as washing alkalis.

Carboxymethyl cellulose optical brighteners, dyes and/or perfumes may be used as additives, preferably in a quantity of from 0.1 td 1.0% by weight in each case.

The following materials may be used as lubricants, preferably in a quantity of from 0 to 8% by weight: Lubricants are materials used in the extrusion of the crude mixture to obtain a good strand and a smooth, crackfree surface. Suitable lubricants are high-melting fats, waxes and paraffins having melting points above 40"C to about 60"C. Other suitable lubricants are high-melting nonionic surfactants, such as for example tallow alcohol containing 25 ethylene oxide units or coconut oil fatty acid monoethanolamide.

The detergent bar according to the invention is prepared in known manner.

The individual components are preferably mixed together at a temperature of from 30 to 60"C and preferably at a temperature of from 40 to 50"C, homogenized, preferably on a three-roll stand, and pressed in known manner.

The detergent bar according to the invention advantageously contains no substances which cause eutrophication of waters, such as sodium tripolyphosphate for example. However, it is also possible to replace part of the aluminium silicate by the sodium and/or potassium salts of orthophosphate, pyrophosphate and/or triphosphate.

The detergent effect, the handling properties and the dissolving rate of the detergent bar according to the invention are comparable with those of the known detergent bar according to GB-PS 2 127 426.

EXAMPLES The chemical constitution of the commercial products used in the Examples is as follows: Texapon OT . laurylsulfate Marlipal SU : tallow alcohol containing 25 moles ethylene oxide Rewomid C 212 : coconut oil fatty acid monoethanolamide.

Table I shows the composition of the samples used. Samples 1, 2,3,4, 5, 6,7, 8 and 9 are detergent bars according to the invention. The detergent bars are prepared by placing Texapon OT and water in a kneader and kneading with heating to 4Q--50"C until the Texapon needles have dissolved.

Rewomid C 212 and Marlipal SU are then added in the form of a 40% emulsion, followed by the remaining powder components. The mixture is extruded to detergent bars at 65"C.

Foam generation and foam stability are determined using a friction foam tester.

Foam generation and foam stability are read off in milliliters after 5 minutes and 30 minutes, respectively. The tests are carried out in distilled water and in water having a hardness of 15 Gh (German hardness).

The results are shown in Table II below.

TABLE I 1 2 3 4 5 6 7 8 9 10 11 ABS - - - - - - - - - 29.1% 29.1% Tallow - - - - - - - - - 6.1% 6.1% Texapon OT 27.6% 27.6% 27.6% 27.6% 27.6% 27.6% 27.6% 27.6% 23.0% - Marlipal SU - - - - - 3.0% 3.0% 3.0% 3.0% - Rewomid C212 3.0% 3.0% 3.0% 3.0% 3.0% - - - - - Na carbonate 12.0% 12.0% 10.0% 8.0% 8.0% 8.0% 8.0% 10.0% 10.0% 16.4% 16.4% Na sulfate 0.6% 0.6% 0.6% 0.6% 0.6% 0.6% 0.6% 0.6% 6.5% - Na triphosphate - 6.0% - - 6.0% - 60% - - 9.1% 4.55% Na silicate 4.0% 4.0% 4.0% 4.0% 4.0% 4.0% 4.0% 5.6% 4.0% 4.3% 4.3% Ca carbonate 18.0% 18.0% 25.0% 28.0% 28.0% 28.0% 28.0% 24.0% 28.0% 27.3% 27.3% Mg carbonate - - - 2.0% 2.0% 2.0% 2.0% 2.0% 2.0% - Wessalith 9.6% 4.8% 9.6% 9.6% 4.8% 9.6% 4.8% 9.6% 9.6% - 4.55% Mg sulfate - - - - - - - - - 1.2% 1.2% Bentonite - - - - - - - - - 3.0% 3.0% CMC - - - - - - - - - 0.5% 0.5% TiO2/dye/fragrance - - - - - - - - - 0.4% 0.4% Perfume - - - - - - - - - 0.3% 0.3% Tot. water 25.2% 24.0% 20.2% 17.2% 16.0% 17.2% 16.0% 17.6% 13.9% 2.3% 2.3% TABLE II Foaming power and foam stability of detergent bars

Foaming power Foam stability Reduction Foaming power Foam stability Reduction Formulation in mil after 5' in mil after 30' in % in ml after 5' in ml after 30' in % No.1 1150 850 26 1150 850 26 No.2 1300 1100 15 1050 900 14 No.3 1300 1150 12 1100 900 18 No.4 1350 1150 15 1300 1150 12 No.5 1200 950 21 1100 850 23 No.6 1350 850 37 1200 700 42 No.7 1250 750 40 1050 600 43 No.8 1350 900 33 1100 500 55 No.9 1300 1050 19 1250 800 36 No.10 1300 1050 19 1250 1000 20 No.11 1450 1200 17 1350 1100 19 Sample weight: 1 g in 200 ml dist. H2O 1 g in 200 ml H2O of 15 Gh TABLE Ill Dissolving rate of detergent bars Method: "drum abrasion test" The dissolving rate is determined in an apparatus of the type shown in Figure 1 using normal tapwater at approx. 1 2-140C with a hardness of 4 Gh.

The following conditions are applied: Sample weight: 1.0+0.01 g Waterthroughput: 2 1/min.

Rotational speed: 35 r.p.m.

Running time: 25' Formulation Quantity weighed out g Reduction % No. 1 0.03 g+0.01 g 97 No.2 0.13 g#0.01 g 87 No.3 0.08 g+0.01 g 92 No.4 0.04 g+0.01 g 96 No.5 100 No.6 100 No.7 0.07 g+0.01 g 93 No.8 0.14 g+0.01 g 86 No.9 0.21 g+0.01 g 79 No. 10 0.29 g+0.01 g 71 No.11 0.27 g+0.01 g 73 Figure 1 illustrates the apparatus used to determine the dissolving rate. This apparatus consists of a t=otor 1, a shaft 2 and a cylindrical cage 3. The cylindrical gage 3, which has an external diameter of 200 arn, is covered by a 1 mm mesh sieve cloth 4. The interior of the cage 3 is divided up by partitions 6 into individual sections 5, so that the various samples 7,8,9, 10 and 11 may be tested at the same time.The partitions 6 have an inner opening with an internal diameter of 100 mm. The partitions 6 are held together by four long screws with metal sleeves pushed on to act as spacers.

The cylindrical cage 3 is rotated horizontally about its longitudinal axis at 35 r.p.m. by the motor 1 via the shaft 2. Part of the cylindrical cage 3 dips into a tank 12 of water of which the dimensions are such that the detergent bar samples are completely covered by the water 13 flowing through. The water flows through the tank 12 at a rate of 2 I/minute, being introduced through the inlet 14 and removed through the outlet 15.

TABLE IV lssolving rate of detergent bars Method: "riverwashing" (figures in %) Formulation 100 times 200 times 300 times 400 times 1 3.6 6.8 17 24 4 2.9 6.2 13.7 22.6 5 3.3 6.6 11.4 18.2 8 1.4 3.1 8.4 12.9 9 2.7 4.7 9.1 12.0 10 1.3 3.4 9.6 15.6 In this test method, a cotton towel is spread over a solid support and the detergent bar rubbed thereon 400 times under running cold water (approx. 12"C).

Claims (1)

1. CLAIM

   A detergent bar, characterized in that it contains aluminium silicate.