SE460053B - PARTICULAR WHITING DETERGENT COMPOSITION AND ITS APPLICATION IN THE WASHING PROCEDURE - Google Patents

Description

l0 15 20 25 30 there is a trend towards washing at lower temperatures.

In order to enhance the bleaching effect of peroxy bleaches, substances called activators have previously been used together with the peroxy compound. It is generally considered that the interaction between peroxy compound and activator leads to the formation of a peroxyacid which at lower temperatures is a more effective bleaching agent than hydrogen peroxide. A variety of compounds have been proposed as activators for peroxy bleaches including carboxylic acid anhydrides such as those described in U.S. Patents 3,298,775, 3,338,839 and 3,532,634; carboxyl esters such as those described in U.S. Patent 2,995,905; N-acyl compounds such as those described in U.S. Patents 3,912,648 and 3,919,102; cyanoamines as described in U.S. Patent 4,199,466; and acylsulfonamides described in U.S. Patent 3,245,913. i The formation and stability of the peroxyacid bleach in bleach systems containing a peroxy compound and an organic activator is a problem recognized in the art.

For example, U.S. Patent 4,255,452 to Leigh addresses the problem of avoiding the reaction between peroxyacid and peroxy compound which yields what are characterized in the patent as useless products, namely the corresponding carboxylic acid, molecular oxygen and water. The patent states that these side reactions are doubly harmful because peracid and per compound are destroyed simultaneously.

The patentee then discloses certain polyphosphonic acid compounds as chelating agents which are said to inhibit the peroxyacid consuming side reaction described above and provide improved bleaching effect. In contrast to these chelating agents, the patentee states that other more commonly known chelating agents, such as ethylenediaminetetraacetic acid (EDTA) and nitrilotriacetic acid (NTA), are virtually ineffective and do not provide any enhanced bleaching effects. Thus, a disadvantage of the bleaching compositions described in the Leigh patent is that they do not allow the use of conventional sequestrants, many of which are cheaper and more readily available than the polyphosphonic acid compounds described.

The effect of silicates on the decomposition of peroxyacid in detergent and / or bleach solutions has not previously been noted in the art. U.S. Pat. Nos. 3,860,391 and 4,292,575 disclose that silicates are conventionally employed as additives in peroxide-containing bleaching solutions for the purpose of stabilizing the constituent peroxide compounds. However, patent holders note that the use of silicates in these bleach solutions can cause other problems in the bleaching processes e.g. the formation of silicate precipitates which are deposited on the bleached goods. Accordingly, the patents are directed to processes for bleaching cellulosic fibers with silicate-free bleach solutions in which the stability of the peroxide is enhanced with compounds other than silicates.

European Patent Publication 0 028 432, published 13 May 1981, discloses a granular detergent composition containing, inter alia, a water-insoluble silicate and an organic compound as an activator of a peroxy bleach. The pH characteristics of this detergent composition are stated to be critical; The pH value in a 2% water slurry is specifically between 2 and 9, and preferably from 4 to 7. On p. 7 of the patent publication, certain polyphosphonic acid compounds are described as being highly preferred constituents of the composition, and the publication states in this context that polyphosphonates have been shown to be uniquely active in stabilizing organic peroxyacids against the generally harmful effects of water-insoluble silicates. especially those belonging to the class zeolite and kaolin. The nature of these adverse effects is not specified. On p. 38 of the publication describes granular detergent compositions in Examples 8-10 which do not contain sodium silicate, and all of these compositions contain Dequest 2041 (ethylenediaminetetramethylenephosphonic acid). The compositions of these examples also contain a compound which is a peroxy activator which is incorporated into agglomerated particles consisting of this activator, a water-insoluble silicate compound and a nonionic surfactant.

Thus, the improved bleaching ability that can be achieved with particulate bleaching detergent compositions containing a peroxyacid compound when these compositions are characterized by the absence of water-soluble silicate compounds has not been previously noted or indicated.

Summary of the Invention The present invention provides a particulate bleaching detergent composition comprising: (a) a bleaching agent comprising a peroxyacid compound and / or a water-soluble salt thereof; and (b) at least one surfactant selected from anionic, cationic, nonionic, ampholytic and zwitterionic detergents; wherein said bleaching detergent composition is substantially free of (i) water-soluble silicate compounds and (ii) agglomerated particles which mainly comprise activator, a water-insoluble silicate compound and a nonionic surfactant. In accordance with the process of the invention, bleaching of stained and / or soiled materials is carried out by contacting these materials with an aqueous solution of the above-mentioned bleaching detergent composition.

The present invention is based on the discovery that the undesired loss of peroxyacid in the aqueous wash solution by reacting peroxyacid with a peroxy compound (or more specifically, hydrogen peroxide formed from this peroxy compound) to form molecular oxygen is markedly reduced in bleach systems which are essentially free of water-soluble silicate compounds. Although the applicant does not wish to be bound by any particular theory as to the mode of action, it is believed that the presence of water-soluble silicates in the peroxy compound / activator bleach system catalyzes the aforementioned reaction between peroxyacid and hydrogen peroxide which leads to loss of active oxygen from the wash solution. otherwise would be available for bleaching. It is known in the art that metal ions, such as iron ions and copper ions, catalyze the decomposition of hydrogen peroxide as well as the reaction between peroxyacid and hydrogen peroxide. However, with respect to this metal ion catalysis, the applicant has surprisingly discovered that conventional sequestrants, such as EDTA and NTA, which have been considered in the art to be ineffective in inhibiting the aforementioned peroxyacid-consuming reaction (see, for example, column 4 of U.S. Patent 4,225,452) , can be incorporated into the compositions of the present invention and stabilize the peroxyacid in solution.

The term "water-soluble silicate compounds" refers to compounds such as sodium silicate which are substantially soluble in aqueous washing solutions and which are often included in conventional bleaching detergent compositions, but which are substantially eliminated in the compositions of the present invention. however, to incorporate substantially water-insoluble silicates, especially aluminosilicates such as clays and zeolites into the bleaching detergent composition described herein, and water-soluble silicate compounds are considered to be much more harmful in terms of peroxyacid stability than water-insoluble substances such as aluminosilicates.

In a preferred embodiment of the invention, the bleaching compositions described herein further contain a sequestering agent to improve in solution the stability of the bleaching peroxyacid compound by inhibiting its reaction with hydrogen peroxide in the presence of metal ions. The term "sequestering agent" as used herein refers to organic compounds capable of forming a complex with cuz ions so that the stability constant (px) of complex formation is equal to or greater than 6 in water of 250 ° C and having an ionic strength of 0.1 mol / liter, pK is defined in the usual way by the formula: pK = - log K g where K represents the equilibrium constant. Thus, for example, the pH values for the complex formation between copper ions and NTA or EDTA are 12.7 and 18.8, respectively, at the specified conditions. The term "sequestering agent" is therefore used herein in a sufficiently limited sense to exclude inorganic compounds commonly used as detergent salts in detergent compositions. Particularly useful sequestrants include EDTA, diethylenetriaminepentaacetic acid (DEPTA) and various phosphonate sequestrants marketed by Monsanto Company under the trademark Dequest, e.g.

Dequest 2000, 2006, 2041, 2051 and 2060.

In addition, in accordance with another embodiment of the invention, the described bleach compositions are distinguished from certain water-soluble silicate-free compositions described in the art by using in the present bleach compositions only sequestering agents having a stability constant not greater than 20 to form Cu2 + complex in water of 250 ° C and at an ionic strength of 0.1 mol / liter. This limitation precludes the presence of polyphosphonic acid compounds such as Dequest 2041 (ethylenediaminetetramethylenephosphonic acid) and Dequest 2060 (diethylenetriaminepentamethylenephosphonic acid) in the bleach compositions of the invention, as these sequestering agents have higher constituent constituents. consequently comprises sodium salts of nitrilotriacetic acid (NTA); ethylenediaminetetraacetic acid (EDTA); ethylenediamine; tetramine, i.e.

N- (CH2-CH2-NH2) 3: bis (aminoethyl) glycol ether-N, N, N1, N'-tetraacetic acid (EGTA); and N (CH 2 -PO 3 H 2) 3 which is marketed under the trademark Dequest 2000. EDTA and the aforementioned Dequest 2000 are particularly preferred for use in this embodiment of the invention.

Detailed Description of the Invention The bleaching detergent compositions of the invention are substantially free of water-soluble silicate compounds and consist of two main constituents: (a) a bleaching agent; and (b) a cleaning surfactant.

The bleach useful in these compositions comprises a water-soluble peroxyacid compound and / or a water-soluble salt thereof. Peroxyacid compounds are characterized by the general formula: O II H00 - C - R - Z in which R is an alkyl group containing from 1 to about 20 carbon atoms, or a phenylene group, and Z is one or more groups selected from hydrogen , halogen, alkyl, aryl and anionic groups. The organic peroxyacids and their salts may contain from about 1 to about 4, preferably 1 or 2, peroxy groups and may be aliphatic or aromatic.

The preferred aliphatic peroxyacids include diperoxyazelanoic acid, diperoxydodecanedioic acid and monoperoxy succinic acid. Among the aromatic peroxyacid compounds useful herein, monoperoxyphthalic acid (MPPA), especially its magnesium salt, and diperoxyterephthalic acid are especially preferred. A detailed description of the preparation of MPPA and its magnesium salt is given on p. 7 - 10 of European Patent Publication 0 027 693, published April 29, 1981, and the aforementioned pages 7 - 10 are incorporated herein by reference.

The bleach may, if desired, in addition to the peroxyacid compound also contain a peroxy compound. The peroxy compounds that are useful include compounds that release hydrogen peroxide in aqueous media, such as alkali metal perborates, e.g. sodium perborate and potassium perborate, alkali metal perphosphates and alkali metal percarbonates. Alkali metal perborates are generally preferred due to their commercial availability and relatively low cost. If desired, an organic activator may be used in conjunction with such a peroxy compound.

Conventional activators such as those described in, for example, U.S. Patent No. 4,259,200, column 4, are suitable for use with the aforementioned peroxy compounds, and this disclosure is incorporated herein by reference. The polyacylated amines are generally of particular interest, and especially tetraacetylethylenediamine (TAED) is a highly preferred activator. TAEDs are preferably included in the compositions of the invention in the form of "coated" granules containing TAEDs and a suitable carrier material such as a mixture of sodium and potassium triphosphate. These coated TAED granules are conveniently prepared by mixing finely divided particles of sodium triphosphate and TAED and then spraying on this mixture an aqueous solution of potassium triphosphate and using suitable granulating equipment such as a rotary drum type granulator. A typical method of making this type of coated TAED is described in U.S. Patent 4,283,302 to Foret et al. The TAED granules have a preferred particle size distribution as follows: 0 - 20% greater than 150/1; 10 - 100% greater than 100 Ii but less than l50 / 1; 0 - 50% less than 75 / J; and 0 - 20% less than 50 fn Another particularly preferred particle size distribution is obtained when the median particle size of TAED is 160 μl, i.e. 50% of the particles are larger than 160 .mu.m. The aforementioned size distribution refers to the TAED contained in the coated granules and not the coated granules themselves. Molar ratios between peroxy compound and activator can vary within a wide range depending on the choice of peroxy compound and activator.

However, molar ratios of from about 0.5: 1 to about 10 15 20 25 30 10 25: 1 are generally suitable for imparting satisfactory bleaching properties.

The bleaching detergent composition of the invention is characterized in that it is substantially free of (i) water-soluble silicate compounds and (ii) agglomerated particles consisting essentially of a mixture of three components: the organic activator of the peroxy compound; a water-insoluble silicate compound such as clay or zeolite; and a nonionic surfactant, which mixture constitutes at least 80% by weight of the agglomerated particles. The agglomerated particles excluded from use herein are of the type manufactured in equipment such as a "pan granulator" and serve to incorporate the bleach activator into a matrix of material as described in European Patent Publication 0 028 432. In a special embodiment of the invention, the bleach compositions are further characterized in that they are substantially free of sequestering agents having a stability constant greater than about 20 for Cu 2+ complex formation in water at 250 ° C and at an ionic strength of 0.1 mol / liter.

The water-insoluble silicate materials which can be advantageously used in the present bleach compositions are preferably aluminosilicates such as zeolites and smectite clays. The crystalline types of zeolites that can be used include those described in the "Zeolite Molecular Series" by Donald W Breck, published in 1974 by John Wiley & Sons, and representative available zeolites are listed in Table 9.6 on p. 747 - 749 in the text, which table is incorporated herein by reference. Type A zeolite structures are particularly desirable and are extensively described in the art; see for example 10 15 20 25 30 ll p. 133 in the aforementioned text by Breck and also U.S. Pat. No. 2,882,243. The zeolites are particularly useful as detergent salts in high performance detergent compositions.

The aforementioned smectite clays are three-layer clays which are characterized by the ability of the layer structure to multiply its volume by swelling or expanding in the presence of water and give thixotropic gelatinous substances. There are two classes of smectite clays: the first class includes alumina in the silicate crystal lattice; in the second class, magnesium oxide is included in the silicate crystal lattice. Atomic substitution by iron, magnesium, sodium, potassium, calcium and the like can occur inside the crystal lattice in sectarian clays. It is common to distinguish the clays on the basis of their dominant cation. For example, a sodium clay is one in which the cation is predominantly sodium. As for the present bleaching detergent compositions, aluminosilicates in which sodium is the predominant cation, such as bentonite clays, are preferred. Among the bentonite clays, those from Wyoming (commonly referred to as western or Wyoming bentonite) are especially preferred.

Calcium and magnesium clays are also useful but are less preferred in this invention.

Preferred swelling bentonites of this type are sold under the trade names Mineral Colloid, as industrial bentonites, by Benton Clay Company which is a subsidiary of Georgia Kaolin Co. These substances are the same as those previously sold under the THIXO-JEL brand and are selectively broken and enriched bentonites, and those considered most useful are available as Mineral Colloid No. 101, etc., which correspond to THIXO-JBL Nos. 1, 2, 10 Such substances have pH values (6% concentration in water) in the range of 8 to 9,4, maximum free moisture content of about 8%, and specific weights of about 2 , 6, and of the powdered varieties of these substances, at least about 85% (and preferably 100%) passes through a 200 mesh screen (American screen series). The bentonite is more preferably one in which virtually all particles (i.e. at least 90% of these, and preferably more than 95%) pass through a 325 mesh screen, and most preferably all particles should pass through such a screen. The swelling capacity of the bentonite in water is usually in the range of 3 to 15 ml / gram, and its viscosity, at 6% concentration in water, is usually from about 8 to 30 centipoise.

In a particularly preferred embodiment of the invention, the carrier particles comprise agglomerates of finely divided bentonite having particle sizes of less than 200 mesh, agglomerated into particles having sizes substantially in the range of 10 - 100 mesh, having a bulk density in the range of 0.7 to 0, 9 g / ml and a moisture content of 8 to 13%. These agglomerates contain about 1 to 5% of a binder or agglomerating agent which helps to maintain the agglomerate in an undisturbed state until it is added to water, in which it is intended to decompose and slurry.

A detailed description of the method of making these agglomerates is given in U.S. Patent Application 366,587, filed April 8, 1982, which is incorporated herein by reference.

Instead of using THIXO-JEL or Mineral Colloid bentonites, one can also use equivalent competing products, such as the one sold by American Colloid 10 15 20 25 30 13 Company, Industrial Division, as General Purpose Bentonite Powder, 325 mesh, of which at least 95 % is finer than 325 mesh or 44 11 in diameter (wet particle size) and at least 96% is finer than 200 mesh or 74} 1 in diameter (dry particle size). Such an aqueous aluminosilicate consists in principle of montmorillonite (at least 90%), with minor proportions of feldspar, biotite and selenite. A representative composition, on an "anhydrous" basis, is 63.0% silica, 21.5% alumina, 3.3% ferric iron (as Fe 2 O 3), 0.4% ferrous iron (as Fe 0), 2.7 % magnesium (as MgO), 2.6% sodium and potassium (as Na 2 O), 0.7% calcium (as CaO), 5.6% crystal water (as H 2 O) and 0.7% trace elements.

Although western bentonites are preferred, it is also possible to use synthetic bentonites, such as those which can be made by treating Italian or similar bentonites, which contain comparatively small proportions of exchangeable monovalent metals (sodium and potassium), with alkaline substances. such as sodium carbonate, to increase the cation exchange capacity of these products. It is considered that the Na 2 O content of the bentonite should be at least 0.5%, preferably at least 1% and most preferably at least 2% so that the clay can swell to the desired extent, and provide good emollient and dispersing properties in aqueous suspension. Preferred swelling bentonites of the described synthetic types are sold under the trade names Laviosa and Winkelmann, e.g. Laviosa AGB and Winkelmann G-13.

The compositions of the present invention contain one or more surfactants selected from anionic, nonionic, cationic, ampholytic and zwitterionic detergents. Among the anionic surfactants useful in the present invention are those surfactants which contain an organic hydrophobic group having about 8 to 26 carbon atoms and preferably 10 to 18 carbon atoms in the molecular structure and at least one aqueous solubilizing group selected from the groups sulfonate, sulfate, carboxylate, phosphonate and phosphate, so that a water-soluble detergent is obtained.

Examples of suitable anionic detergents are soaps such as water-soluble salts (eg the sodium, potassium, ammonium and alkanolammonium salts) of higher fatty acids, or resin salts containing between about 8 and 20 carbon atoms and preferably 10-18 carbon atoms. Suitable fatty acids can be obtained from oils and waxes of animal or vegetable origin, for example tallow, fat, coconut oil and mixtures thereof. Particularly useful are the sodium and potassium salts of fatty acid mixtures derived from coconut oil and tallow, for example sodium, coconut soap and potassium tallow soap.

The class of anionic detergents also includes water-soluble sulfated and sulfonated detergents having an alkyl radical containing between about 8 and 26 and preferably between about 12 and 22 carbon atoms. (The term "alkyl" includes the alkyl moiety of higher acyl radicals.) Examples of sulfonated anionic detergents are higher alkyl monocyclic aromatic sulfonates such as the higher alkylbenzene sulfonates containing between about 10 and 16 carbon atoms in the higher straight or branched chain alkyl group, such as sodium, potassium and the ammonium salts of higher alkylbenzenesulfonates, higher alkyltoluenesulfonates and higher alkylphenol sulfonates.

Other suitable anionic detergents are olefin sulfonates, including long chain alkene sulfonates, long chain hydroxyalkane sulfonates or mixtures of alkene sulfonates and hydroxyalkane sulfonates. The olefin sulfonate detergents can be prepared in a conventional manner by reacting SO 3 with long chain olefins containing between about 8 and 25 and preferably between 12 and 21 carbon atoms, such as olefins of the formula RCH = CHR 1, in which R represents a higher alkyl group having 6 atoms and R 1 represents an alkyl group having between about 1 and 17 carbon atoms or hydrogen, to obtain a mixture of sultones and alkene sulfonic acids which are then treated to convert the sultones to sulfonates. Other examples of sulfate or sulfonate detergents are paraffin sulfonates containing between about 10 and 20 carbon atoms, preferably between about 15 and 20 carbon atoms. The primary paraffin sulfonates are prepared by reacting long-chain alpha-olefins with bisulfites. Paraffin sulfonates with the sulfonate groups distributed along the paraffin chain are described in U.S. Pat. Nos. 2,503,280, 2,507,088, 3,260,741 and 3,372,188 and German Pat. No. 735,096.

Other suitable anionic detergents are sulfated ethoxylated higher fatty alcohols of the formula RO (C 2 H 4 O) mSO 3 M, in which R is fatty alkyl having from 10 to 18 carbon atoms, m is from 2 to 6 (preferably has a value of from about 1/5 to 1 / 2 of the number of carbon atoms 1 R) and M is a solubilizing salt-forming cation, such as alkali metal, ammonium, lower alkylamino or lower alkanolamino, or a higher alkylbenzene sulfonate in which the higher alkyl has 10 to 15 carbon atoms. The proportion of ethylene oxide in the polyethoxylated higher alkanol sulfate is preferably 2 to 5 moles of ethylene oxide groups per mole of anionic detergent, with 3 moles being particularly preferred, especially when the higher alkanol has 16 to 15 carbon atoms. To maintain the desired balance between hydrophilic and lipophilic groups, when the carbon atom content of the alkyl chain is in the lower part of the range 10 to 18 carbon atoms, the detergent content of ethylene oxide can be reduced to about 2 moles per mole, while the number of ethylene oxide groups can be increased to 4 or 5 and in some cases up to 8 or 9, when the higher alkanol has 16 to 18 carbon atoms within the upper part of the range. In the same way, the salt-forming cation can be changed to give the best solubility.

It can consist of any suitable solubilizing metal or radical but usually becomes alkali metal, e.g. sodium or ammonium. If lower alkylamine or alkanolamine groups are used, the alkyls and alkanols will usually contain from 1 to 4 carbon atoms and the amines and alkanolamines may be mono-, di- and trisubstituted as in monoethanolamine, diisopropanolamine and trimethylamine. A preferred polyethoxylated alcohol sulfate detergent is available from Shell Chemical Company and is marketed as Neodol 25-3S.

The most preferred water-soluble anionic detergent compounds are salts of higher alkyl benzene sulfonates, olefin sulfonates and higher alkyl sulfates with ammonium and substituted ammonium (such as mono-, di- and triethanolamine), alkali metal (such as sodium and potassium) and alkaline earth metal ( such as calcium and magnesium).

Among the anionic substances listed above, sodium linear alkyl benzene sulfonates (LABS) are the most preferred, and especially those in which the alkyl group is a straight chain alkyl radical having 12 or 13 carbon atoms.

The nonionic synthetic organic detergents are characterized by the presence of an organic hydrophobic group and an organic hydrophilic group and are typically prepared by condensation of an organic aliphatic or alkylaromatic hydrophobic compound with ethylene oxide (hydrophilic to nature). Virtually any hydrophobic compound having a carboxy, hydroxy, amido or amino group with a free hydrogen bonded to the nitrogen can be condensed with ethylene oxide or with the polyhydrated product thereof, i.e. polyethylene glycol, and form a nonionic detergent. The length of the hydrophilic chain or of the polyoxyethylene chain can be easily adjusted to give the desired balance between hydrophobic and hydrophilic groups.

The nonionic detergent used is preferably a poly-lower alkoxylated-higher alkanol in which the alkanol has 10 to 18 carbon atoms and in which the molar number of lower alkylene oxide (having 2 or 3 carbon atoms) is from 3 to 12.

Among these substances, it is preferable to use those in which the higher alkanol is a higher fatty alcohol having 11 to 15 carbon atoms and which contains from 5 to 9 lower alkoxy groups per mole. The lower alkoxy group is preferably ethoxy, but in some cases it can be advantageously mixed with propoxy, the latter, in the case being included, usually constituting a smaller part (less than 50%). Examples of such compounds are those in which the alkanol has 12 to 15 carbon atoms and which contain about 7 ethylene oxide groups per mole, e.g. Neodol 25-7 and Neodol 23-6.5, which products are manufactured by Shell Chemical Company, Inc. The former is a condensation product of a mixture of higher fatty alcohols with an average of about 12 to 15 carbon atoms, with about 7 moles of ethylene oxide and the latter is a corresponding mixture in which the carbon atom content of the higher fatty alcohol is 12 to 13 and the number of ethylene oxide groups is on average 6.5 per mole. The higher alcohols are primary alkanols. Other examples of these detergents include Tergito1.Q 15-S-7 and Tergitol 15-S-9, both of which are linear secondary alcohol ethoxylates manufactured by Union Carbide Corporation. The former is a mixed ethoxylated product of a linear secondary alkanol having 11 to 15 carbon atoms and 7 moles of ethylene oxide and the latter is a similar product but reacted with 9 moles of ethylene oxide. Higher molecular weight nonionics can also be used in the present compositions, such as Neodol 45-1, which are similar condensation products between ethylene oxide and higher fatty alcohols, the higher fatty alcohol having 14 to 15 carbon atoms and the number of ethylene oxide groups being about 11 per mol. These products are also manufactured by Shell Chemical Company.

Zwitterionic detergents, such as betaines and sulphobetaines, of the following formula are also useful: wherein R represents a alkyl group having between about 8 and 18 carbon atoms, R2 and R3 represent each is an alkyl or hydroxyalkyl group having about 1 to 4 carbon atoms, R 4 represents an alkylene or hydroxyalkylene group having 1 to 4 carbon atoms, and X is C or S = O. The alkyl group may contain one or more intermediate bonds, such as amido, ether or polyether bonds, or non-functional substituents, such as hydroxyl or halogen, which do not appreciably affect the hydrophobic character of the group. When X is C, the detergent denotes a betaine, and when X is S = O, the detergent is denoted a sulfobetaine or sultain. 10 15 20 25 '30 19 Cationic substances can also be used. These consist of surfactant detergent compounds, containing an organic hydrophobic group which forms part of a cation when the compound is dissolved in water, and an anionic group. Typical cationic substances are amine and quaternary ammonium compounds.

Examples of suitable synthetic cationic detergents are: common primary amines of the formula RNH 2, in which R represents an alkyl group having about 12 to 15 carbon atoms; diamines of the formula RNHC2H4NH2, in which R represents an alkyl group having between 12 and 22 carbon atoms, such as N-2-aminoethyl-stearylamine and N-2-aminoethyl-myristylamine; amide-linked amines such as those of the formula R 1 CONHC 2 H 4 -NH 2, in which R 1 represents an alkyl group having about 8 to 20 carbon atoms, such as N-2-amino-ethyl-stearylamide and N-amino-ethylmyristylamide; quaternary ammonium compounds in which typically one of the groups attached to the nitrogen atom is an alkyl group having about 8 to 22 carbon atoms and three of the groups attached to the nitrogen atom are alkyl groups containing 1 to 3 carbon atoms, including alkyl groups having inert substituents, such as phenyl groups, in which case there is an anion such as halogen, acetate, methyl sulphate, etc. The alkyl group may contain intermediates such as amide, which do not substantially affect the hydrophobic character of the group, for example quaternary stearylamidopropylammonium chloride. Typical quaternary ammonium detergents are ethyl dimethyl stearyl ammonium chloride, benzyl dimethyl stearyl ammonium chloride, trimethyl stearyl ammonium chloride, trimethyl cetyl ammonium bromide, dimethyl ethyl lauryl ammonium chloride, dimethyl chloride and dimethyl propyl corresponding methyl sulphates and acetates. Ampholytic detergents are also useful according to the invention. Ampholytic detergents are well known in the art and many useful detergents of this class are described by Schwartz, Perry and Berch in the aforementioned "Surface Active Agents and Detergents". Examples of suitable amphoteric detergents are alkyl beta-imidodipropionates, R 11 (C 2 H 4 COOM) 2; alkyl beta-aminopropionates, RN (H) C 2 H 4 COM; and long chain imidazole derivatives having the general formula: CH / \ N CH I! IR ~ C - N-CHZCHZOCHZCOOM / \ OH CHZCOOM 2 2 wherein in each of the above formulas R represents an acyclic hydrophobic group having between about 8 and 18 carbon atoms, and M is a cation which neutralizes the charge of the anion . Particularly suitable amphoteric detergents are the disodium salt of undecylcycloimidine ethoxythionic acid 2-ethionic acid, dodecyl-beta-alanine and the inner salt of 2-trimethylamino-lauric acid.

The bleaching detergent composition of the invention may optionally contain a detergent salt of the type generally used in detergent compositions. Useful detergent compositions are the conventional inorganic water-soluble detergent salts, such as, for example, water-soluble salts of phosphates, pyrophosphates, orthophosphates, polyphosphates, carbonates and the like. Organic detergent compositions are water-soluble phosphonates, polyphosphonates, polyhydroxy sulfonates, polyacetates, carboxylates, polycarboxylates, succinates and the like.

Particular examples of inorganic detergent phosphates are sodium and potassium tripolyphosphate, pyrophosphate and hexametaphosphate. The organic polyphosphonates especially include, for example, the sodium and potassium salts of ethane-1-hydroxy-1,1-diphosphonic acid and the sodium and potassium salts of ethane-1,2,2-triphosphonic acid. Examples of these and other phosphorus-containing detergent active compounds are given in U.S. Pat. Nos. 3,213,030, 3,422,021, 3,422,137 and 3,400,176. Pentasodium tripolyphosphate and tetrasodium pyrophosphate are especially preferred water-soluble inorganic detergent salts.

Particular examples of non-phosphorus inorganic detergent active compounds are water-soluble inorganic carbonate and bicarbonate salts. Alkali metal, for example sodium and potassium, carbonates and bicarbonates are especially suitable here.

Water-soluble organic detergent compounds are also useful. Thus, for example, alkali metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates and polyhydroxysulfonates are suitable detergent compositions for the compositions and method of the invention. Particular examples of detergent polyacetate and polycarboxylate compounds are sodium, potassium, lithium, ammonium and substituted ammonium salts of ethylenediaminetetraacetic acid, nitrilotriacetic acid, benzenepoly (i.e. penta- and tetra-) carboxylic acid oxycarboxymic acid. Water-insoluble detergent active compounds can also be used, in particular complex silicates and in particular complex sodium aluminum silicates such as zeolites, e.g. zeolite 4A, which is a type of zeolite molecule in which the monovalent cation is sodium and in which the pore size is about 4 Ångström. The preparation of this type of zeolite is described in U.S. Pat. No. 3,114,603. The zeolites may be amorphous or crystalline and contain hydrating water in a manner known in the art. The detergent compositions of the invention may advantageously contain an inert, water-soluble filler salt. A preferred filler salt is alkali metal sulfate, such as potassium or sodium sulfate, with the latter being particularly preferred.

Various adjuvants may be included in the bleaching detergent compositions of the invention. These generally include perfumes; dyes, e.g. pigments and dyes; bleaching agents such as sodium perborate; antifoulants such as alkali metal salts of carboxymethylcellulose; optical brighteners, such as anionic, cationic or nonionic bleaches; foam stabilizers, such as alkanolamides, and the like, all of which are well known for use in detergent compositions in the laundry industry. Flow promoters, generally referred to as "flow aids", may also be used to maintain the particulate bleaching detergent composition in the form of free-flowing granules or powders. Starch derivatives and special clays are commercially available as additives which improve the flowability of particulate compositions which are otherwise sticky or degenerate, and two such clay additives are currently sold under the trade names "Satintone" and "Microsil".

A preferred bleaching detergent composition of the invention typically comprises (a) from about 2 to 50% by weight of bleaching agent consisting of a peroxyacid compound and / or a water-soluble salt thereof; (b) from about 5 to 50% by weight of a detergent surfactant; (c) from about 1% to about 60% by weight of a laxative salt; and (a) from about 0.1% in about 10% by weight of a sequestering agent; which composition is characterized in that it is substantially free of (i) water-soluble silicate compounds and (ii) agglomerate particles consisting essentially of said activator, a water-soluble silicate compound and a nonionic surfactant. The remainder of the composition consists mainly of water, filler salts such as sodium sulfate, and minor additives selected from the various adjuvants described above.

The particulate bleaching detergent composition of the invention is prepared by mixing the bleaching agent and any sequestering agent with the spray-dried detergent composition, the latter being formulated in such a manner that it does not use water-soluble silicate compounds, and especially not sodium silicate. Presence of very small amounts of water-soluble silicate compounds in the final composition, i.e. less than about 0.5% by weight, preferably less than about 0.2% by weight and most preferably not more than about 0.1% by weight, which may occur when using silicate-containing pigments or dyes, or in contact between the aqueous slurry base mixture and residues of sodium silicate in the spray tower, is included in the present invention. l 10 15 20 25 24 The spray drying of a silicate-free detergent composition can give a rather dusty granular product due to the fact that no silicate is included as a binder for the spray-dried grains. However, alternative organic binders may be used, such as, for example, starch, carboxymethylcellulose and similar substances. The strength of the spray-dried granules can also be increased by maximizing the content of solids in the silicate-free slurry in the mixer and / or by keeping the inlet temperature of the hot air stream to the spray tower as low as possible.

The bleach can either be mixed directly with the spray-dried powder or the bleach and any sequestering agent can be coated individually or together with a covering material to prevent premature activation of the bleach. The coating process is carried out in accordance with methods known in the art.

Suitable cover materials include compounds such as magnesium sulfate, polyvinyl alcohol, lauric acid and its salts and the like.

The bleaching detergent composition of the invention is added to the wash solution in an amount sufficient to provide from about 3 to about 100 parts of active oxygen per million parts of solution, and a content of from about 5 to about 40 ppm is generally preferred.

The particulate bleaching detergent compositions described above can be made by methods such as spray drying, dry blending, or agglomerating the individual ingredients. Example 1 A preferred silicate-free bleaching detergent composition consists of the following: Component weight percent sodium linear C10-C13 alkylbenzenesulfonate, 6 ethoxylated C11-C18 primary alcohol (11 moles EO per mole of alcohol) 3 soaps (sodium salt of C12-C22-carboxylic acid) 4 pentasodium tripolyphosphate (TPP) 32.0 EDTA 0.5 monoperoxyphthalic acid (MPPA) magnesium salt 7 carboxymethylcellulose 0.5 optical brighteners, pigments and perfume 0.4 proteolytic enzymes 0.5 sodium salt and water residue The above product is prepared by spray drying of a water slurry containing 60% by weight of a mixture containing all of the above components except the enzyme, perfume, and monoperoxyphthalic acid (MPPA).

The resulting particulate spray dried product has a particle size in the range of 14 mesh to 270 mesh (US screen series). The spray dried product is then mixed in a rotating drum, with appropriate amounts of MPPA with similar particle size, enzyme and perfume to give a particulate product having a moisture content of approximately 14% by weight. The product described above is used for washing soiled textiles by hand washing or by washing in an automatic washing machine, whereby good washing and bleaching results are obtained in both washing methods.

Other satisfactory products can be obtained by varying the levels of the following main components of the above composition as follows: Component Weight percent alkyl benzene sulfonate 4-12 ethoxylated alcohol 1-6 soap 1-10 TPP 15-50 enzymes 0.1-1 EDTA 0.1 -2 MPPA l-20 For highly concentrated high performance detergent powders, the alkylbenzenesulfonate, TPP and soap components of the composition described above can be omitted, and the content of ethoxylated alcohol can be increased to an upper limit of 20%.

Example 2 Bleaching tests are carried out according to the following description in which the bleaching ability of a water-soluble silicate-free bleaching detergent composition according to the invention is compared with a corresponding silicate-containing composition, the latter composition being comparable to the aforementioned in almost every respect except water-soluble silicate compound. The bleach used is a mixture of monoperoxyphthalic acid salt and sodium perborate. The compositions 27 are prepared by subsequently adding to a spray-dried particulate detergent composition granules of the bleach composition H-48 (described in the footnote to Table 1) to give the bleaching detergent compositions A and B shown in Table 1 below. The numerical values given in the table refers to percentages, in percentage by weight, of each component in the preparation. Table 15 Component sodium linear C10-C13-alkylbenzenesulfonate - ethoxylated C11-C18 primary alcohol (11 moles EO per mole of alcohol) soap (sodium salt of C1-2-C22-carboxylic acid) sodium silicate (Na2O: 2SiO2) pentasodium tripolyphosphate (TPP) optical brightener (stilben) sodium perborate tetrahydrate 11-48 u) EDTA (disodium salt) sodium sulfate water composition A silicate-free 6.00% 3.50 2.50 35.00 0.22 3.00 9.00 1, 00 35.00 residue B silicate- containing 6.00% 3.50 2.50 9.00 35.00 0.22 3.00 9.00 1.00 10.60 residue (1) A bleach composition sold by Interox Chemicals Limited, London, England, containing about 65% by weight of magnesium monoperoxyphthalate, 11% by weight of magnesium phthalate and the balance water.

Test method The active oxygen content of the solution is determined as a function of time for washing solutions containing compositions A and B, respectively, using the following procedure: A liter of tap water is introduced into a two-liter beaker and then heated to a constant temperature of 600 ° C. in a water bath. Ten grams of the composition (A or B) to be tested is added to the beaker (time = 0) with thorough stirring and gives a uniform washing solution. After given time intervals (3, 7, 13, 20, 30, 40 and 50 minutes) a 50 ml sample is taken from the washing solution and the total active oxygen content is determined by the procedure given below.

Determination of the total active content 02 The above 50 ml sample is poured into a 300 ml Erlenmeyer flask containing 15 ml of a sulfuric acid / molybdate mixture, the latter mixture being prepared on a larger scale by dissolving 0.18 g of ammonium molybdate in 750 ml of deionized water. then 320 ml of H 2 SO 4 (about 36 N) were added with stirring. The solution in the Erlenmeyer flask is stirred thoroughly, after which 5 ml of a 10% KI solution in deionized water is added thereto. The Erlenmeyer flask is closed with a stopper, shaken and then allowed to stand in a dark room for about seven minutes. The solution in the flask is then titrated with a solution of 0.1 N sodium thiosulfate in deionized water. The required volume of thiosulphate, in milliliters, is equal to the total active oxygen content, in millimoles / liter, in the washing solution. The experimental results for the two tested compositions are given in Table 2 below. 10 15 30 Table 2 Total active oxygen in the washing solution (mmol / liter) time AB (min) (silicate- (silicate-free) ___. Containing) 4.8 2.4 7 4.4 '1.2 13 Å 4, 2 1.0 20 3.9 0.8 30 V 3.7 0.6 40 3.4 0.5 50 3.2 0.4 As shown in Table 2, the silicate-free composition A is considerably more stable and is characterized of a much slower loss of active oxygen from solution than the corresponding silicate-containing composition B.

Claims (33)

10 15 20 25 31 P a t e n t k r a v A particulate bleaching detergent composition, characterized in that it comprises: (a) a bleaching agent consisting of a peroxyacid compound and / or a water-soluble salt thereof; and (b) at least one surfactant selected from anionic, cationic, nonionic, ampholytic and zwitterionic detergents; which bleaching detergent composition is substantially free of (i) water-soluble silicate compounds and (ii) agglomerated particles which consist essentially of a mixture of activator, a water-insoluble silicate compound and a nonionic surfactant. Composition according to Claim 1, characterized in that it also contains a sequestering agent. Composition according to Claim 2, characterized in that the sequestering agent consists of ethylenediaminetetraacetic acid and / or a water-soluble salt thereof. Composition according to Claim 2, characterized in that the sequestering agent consists of diethylenetriamine pentamethylenephosphonic acid and / or a water-soluble salt thereof. 5. A composition according to claim 1, characterized in that the bleaching agent consists of monoperoxyphthalic acid and / or a water-soluble salt thereof. l0 15 20 32 Composition according to Claim 5, characterized in that the bleaching agent consists of magnesium monoperoxyphthalate. Composition according to Claim 1, characterized in that the bleaching agent also contains a peroxy compound. 8. A composition according to claim 7, characterized in that the peroxy compound is an alkali metal perborate. 9. A composition according to claim 1, characterized in that it also contains a washing-assisting salt. 10. A composition according to claim 9, characterized in that said detergent salt is a zeolite. 11. ll. Composition according to Claim 1, characterized in that the surfactant is an anionic detergent. The combustion position according to claim 11, wherein the anionic detergent is a linear alkyl benzene sulfonate. 13. l3. Composition according to Claim 1, characterized in that it also contains a bentonite clay. 14. l4. Bleaching detergent composition, characterized in that it comprises: (a) from about 1% to about 50% by weight of a bleaching composition consisting of a peroxyacid compound and / or a water-soluble salt thereof; (b) from about 5% to about 50% by weight of a surfactant selected from anionic, cationic, nonionic, ampholytic and zwitterionic detergents; (c) from about 1% to about 60% by weight of a laxative salt; (a) from about 0.1 to 111 parts by weight of a sequestering meal; and le) the remainder water and optionally a filler salt; which bleaching detergent composition is substantially free of (i) water-soluble silicate compounds and (ii) agglomerated particles which consist essentially of a mixture of activator, a water-insoluble silicate compound and a nonionic surfactant. Composition according to Claim 14, characterized in that the bleaching agent consists of monoperoxyphthalic acid and / or a water-soluble salt thereof. Composition according to Claim 14, characterized in that the bleaching agent consists of magnesium monoperoxyphthalate. Composition according to Claim 14, characterized in that the bleaching agent also contains a peroxy compound. 18. A composition according to claim 14, characterized in that the sequestering agent consists of ethylenediaminetetraacetic acid and / or a water-soluble salt thereof. l0 l5 20 25 34 19. A composition according to claim 14, characterized in that the detergent salt is a zeolite. Composition according to Claim 14, characterized in that it also contains a bentonite clay. Bleaching process, characterized in that the stained and / or soiled materials to be bleached are contacted with an aqueous solution of a particulate bleaching detergent composition comprising: (a) a bleaching agent consisting of a peroxyacid compound and / or a water-soluble salt hence; and (b) at least one surfactant selected from anionic, nonionic, cationic, ampholytic and zwitterionic detergents; which bleaching detergent composition is substantially free of (i) water-soluble silicate compounds and (ii) agglomerated particles which consist essentially of a mixture of activator, a water-insoluble silicate compound and a nonionic surfactant. Process according to Claim 21, characterized in that the bleaching agent consists of monoperoxyphthalic acid and / or a water-soluble salt thereof. 23. ZÉ. Process according to Claim 22, characterized in that the bleaching agent consists of magnesium monoperoxyphthalate. 10 15 20 25 35 24. A process according to claim 21, characterized in that the bleaching agent also contains a peroxy compound. 25. A method according to claim 21, characterized in that the surfactant is an anionic detergent. 26. The method of claim 25, wherein the anionic detergent is a linear alkyl benzene sulfonate. 27. A method according to claim 21, characterized in that the composition also contains a sequestering agent. Process according to Claim 27, characterized in that the sequestering node consists of ethylenediaminetetraacetic acid and / or a water-soluble salt thereof. 29. A process according to claim 27, characterized in that the sequestering agent consists of diethylenetriaminepentamethylenephosphonic acid and / or a water-soluble salt thereof. 30. A method according to claim 21, characterized in that the composition also contains a washing-assisting salt. 31. A process according to claim 30, characterized in that the detergent salt consists of pentasodium tripolyphosphate. 36 32. The method of claim 30, wherein the detergent salt is a zeolite. 33. A method according to claim 21, characterized in that the bleaching detergent composition also contains a clay of the smectite type.