US3459665A - Bleaching detergents and washing adjuvants - Google Patents

Description

United States Patent 3,459,665 BLEACHING DETERGENTS AND WASHING ADJUVANTS Joachim Schiefer, Opladen-Lutzenkirchen, and Manfred Dohr, Dusseldorf-Holthausen, Germany, assignors to Henkel & Cie G.m.b.H., Dusseldorf-Holthausen, Germany, a corporation of Germany No Drawing. Filed Apr. 6, 1966, Ser. No. 540,516 Int. Cl. Clld 7/54 U.S. Cl. 252-95 22 Claims ABSTRACT OF THE DISCLOSURE Coated per-oxygen compounds, the coating being water-insoluble at room temperature comprising particles of per compounds coated with an ester of glycerin and at least one member of the group consisting of water-insoluble monocarboxylic acids containing 8 to 26 carbon atoms, water-insoluble hydroxy monocarboxylic acids containing 8 to 26 carbon atoms, aliphatic polycarboxylic acids containing 2 to 10 carbon atoms, phthalic acid and mixtures thereof.

The present invention relates to a novel method and composition of matter for bleaching, comprising bleaching detergents and washing adjuvants. More specifically, the present invention relates to a novel method and composition of matter comprising bleaching with detergents and Washing adjuvants containing hypochlorite ions and per-oxygen compounds.

The detergents of the prior art, which contain per compounds, develop their bleaching action through the thermal decomposition of the per compounds which takes place at temperatures above 80 C. Efforts have already been made to cause the per compounds to become active at lower temperatures, and it has been attempted to achieve this by the use of organic per compounds, such as percarboxylic acids or diacylperoxides, or by combining inorganic or organic per compounds with activators; even in that case, however, temperatures of about 45 C. are still required in order to render the activators effective.

It has long been known that active chlorine is a bleaching agent that bleaches at room temperature. Since in recent times a number of new organic active chlorine compounds have been manufactured industrially on a growing scale, proposals have been made for combining these active chlorine compounds with detergents. However,

since it is not the organic compound itself that does thev bleaching when the organic active chlorine compounds are used, but the hypochlorite that forms when these compounds react with water and alkali, the bleaching mechanism is the same as it is when inorganic active chlorine compounds are used. In all cases, the disadvantage of bleaching with active chlorine consists in the fiber damage which becomes apparent as the temperature rises. Furthermore, care must be takento remove the active chlorine entirely from the bleached material, which is not always done, particularly in household work. A long time ago, a recommendation was made of a post-treatment with sodium thiosulfate, referred to as antichlorine, but a two-step procedure of this kind is impractical.

Patented Aug. 5, 1969 Evidently, it was these disadvantages of active chlorine that prevented detergents containing active chlorine from becoming popular, especially in cases where these products were to be used by persons without chemical knowledge, particularly by housewives.

It is therefore an object of the present invention to provide both a method and a composition of matter for bleaching at both low temperatures and at high temperatures and in an environment in which the temperature is raised from a low temperature to a relatively high temperature. It is a further object of this invention to provide both a method and a composition of matter for bleaching with detergent compositions and washing adjuvants by means of hypochlorite ions at low temperatures and by means of organic peroxides at high temperatures. It is a further object of this invention to provide both a method and a composition of matter for bleaching over wide temperature ranges with bleaches containing hypochlorite ions without damaging fibers at elevated temperatures. It is a further object of the present invention to provide a method for removing active chlorine from bleach at high temperatures and wherein the active chlorine will perform a bleaching function at low temperatures. It is a further object of the present invention to provide a bleach for household use. An additional object of the invention is to provide a composition of matter comprising a novel bleaching detergent and a novel bleaching adjuvant.

It has now been found that use can be made of the good bleaching action of active chlorine without having to put up with the disadvantages associated therewith with or without pourable, and preferably finely pow dered or granular detergents, which comprises active chlorine and per compounds likewise in the form of pourable, i.e., finely powdered or granular preparations, the active chlorine compounds being capable of yielding the active chlorine in cold water, and the particles of the per compounds being coated with glycerin esters of the constitution described below, which release the per compound when warmed in the aqueous phase at temperatures ranging from 40 to 70 C., and preferably from 45 to C.

The materials for coating the per compounds according to the invention are glycerin esters of fatty acids and/ or hydroxy fatty acids, such esters containing for each glycerin radical at least one fatty acid or hydroxy fatty acid radical with 8 to 26, preferably 10 to 24, and especially 16 to 22 carbon atoms, and being bonded in the manner of an ester. However, diglycerides or triglycerides are also usable in which, in addition to at least one higher fatty acid or hydroxy fatty acid radical with the abovegiven carbon atoms, i.e., 8-26, preferably 1024, especially 16-22, radicals of low monocarboxylic acids or hydroxymonocarboxylic acids containing up to 7 carbon atoms and preferably 2 to 7 carbon atoms, are bonded in the manner of esters, such as, for example, the radicals of acetic acid, propionic acid, butyric acid, benzoic acid, glycolic acid, lactic acid and salicyclic acid. According to the invention, however, mixed esters of the above-described monoand diglycerides on the one hand, and diand polycarboxylic acids on the other, can be used. These mixed esters contain preferably at least 0.25 esteroidally bonded radicals of a dior polycarboxylic acid, which may contain up to 10 carbon atoms per radical. These dicarboxylic acids include not only the aliphatic dicarboxylic acids containing 2 to carbon atoms, but also aromatic acids, preferentially phthalic acid.

If the coating materials which are insoluble in the detergent solution are not dispersible in Water, then the temperature at which the coated per compound is released is practically identical with the melting point of the said coating material. Many coating materials differ from those completely insoluble in water by a certain dispersibility in water. In this case, the release of the coated per compound may take place even somewhat below the melting temperature. The dispersibility of a coating substance in water is to be attributed to the presence of free alcoholic hydroxyl groups, free carboxyl groups, or other water solubilizing groups, and generally increases with the number of these groups and decreases with the increasing length of the fatty acid radicals.

Of the glycerin esters that fuse within the above-named range, those are of special practical importance which, on the one hand are not soft, but on the other hand are not too brittle, either. The softness can be measured in a known manner by determining the penetrometric value (cf. Deutsche Einheitsmethoden zur Untersuchung von Fetten, Fettprodukten und verwandten Stoifen [Ger man Standard Methods for Testing Fats, Fat Products and Allied Materials] (="DFG-Einheitsmethoden, Method C-IV 10(53) published by the Deutsche Gesellschaft ftir Fettwissenschaft e.V., Miinster, Westphalia). The ultimate bending tension as determined by DIN standard 51,030 is suitable for specifying the hardness or brittleness; cf. also: H. Pajenkamp, Zement-Kalk-Gips 10 (1957), 63-66. The glycerides serving as coatings advantageously have a penetrometic value at C. of no more than 4 mm., preferably of 0.3 to 3.5 mm., and especially 0.5 to 2.5 mm. The hardness or brittleness, expressed by the ultimate bending tension, is best not lower than g./mm. advantageously it ranges from to 350, and especially from to 250 g./mm. If the numerical values of the above-named physical characteristics of the glycerin esters fall within the stated range, these substances then possess sufficient toughness to withstand the mechanical stress occurring in the transportation and storage of the detergents.

If the detergent containing this bleaching composition or the bleaching composition per se is placed in water, the active chlorine becomes effective first at low temperatures. It acts upon the material being Washed until, as the solution warms, the temperature is reached at which the coated per compound is released. The latter dissolves in water and destroys the hypochlorite, half a mo] of active oxygen being consumed per mol of active chlorine. The speed at which this process takes place increases to the extent that the temperature increases, and damage to the laundry fibers by the active chlorine is thus prevented without the user having to take special precautions. Therefore, the compositions of this invention are very especially suited for the household; they are also, however, valuable for industrial operations and other users, because less attention needs to be devoted to the bleaching process.

The detergents and bleaching compositions of the invention contain the active chlorine in the form of inorganic or organic compounds of a kind which dissolve in cold water or which at least yield active chlorine in cold water. The inorganic active chlorine compounds are the hypochlorites, especially the alkali hypochlorite salts such as sodium or lithium hypochlorite, or the alkaline earth hypochlorite salts, such as calcium hypochlorite, or mixtures thereof, and products formed by the addition of hypochlorites onto alkali or alkaline earth phosphate salts (orthoand polyphosphates, especially tripolyphosphates); these compounds may additionally contain alkali silicates or any combination thereof.

The organic active chlorine compounds, many of which are preferred over the inorganic, are especially the N- chlorine compounds in which one or two chlorine atoms are linked to a nitrogen atom, the third valence of the nitrogen atom leading to an electronegative group, particularly a CO- or -SO group. These compounds include the carboxylic acid or sulfonic acid amides with chlorine on the nitrogen, the above-mentioned amide groups being on aliphatic, cycloaliphatic or aromatic radicals and being able to be present plurally in the molecule, or any combination thereof. Typical representatives of these groups are chlorinated monoor polysulfonamides of benzene, toluene, naphthaline, and the like, chlorinated guanides or biguanides, and their equivalents.

The chlorinated sulfonic acid or carboxylic acid amides to be used according to the invention may also be substituted on the nitrogen by aliphatic, cycloaliphatic or aromatic radicals, or any combination thereof; chlorinated alkyl guanides or alkyl biguanides can also be used.

Lastly, heterocyclic carriers of active chlorine can be used, such as dichloroor trichloroisocyanuric acid or their alkali and alkaline earth salts, or crystalline complex compounds of isocyanuric acids of different degrees of chlorination or their salts (German Green Patent 1,165,036), chlorinated hydantoins or their derivatives, and chlorinated melamines, or any combination thereof.

The following can also be used: chlorination products of substituted ureas or urea condensation products, chlorination products of allophanates, acylated alkylene polyamines, alkylated or non-alkylated monoor dicarboxylic acid amides, urethanes, etc.

Chlorinated uracils, (keto)quinoxalines, (keto)piperazines, (alkyl)glycoluriles, etc., can also be used.

These active chlorine-containing substances can be present in the detergents of the invention either as uncoated particles or, in the interest of better stability in storage, as coated particles. If the particles are to be coated, such a coating material is to be chosen that the coated active chlorine compounds are released at lower temperatures than the coated per compounds. Coating materials of this type are known in the art.

The various prior-art compounds formed by adding hydrogen peroxide onto inorganic or organic fundamental substances are to be used as per compounds, i.e., perhydrate compounds are preferentially used. Of especial practical importance is sodium perborate or similar compounds which differ from sodium perborate in the quantity ratio of their components, Na O, B 0 H 0 and H 0, and which particularly contain more B 0 and/or more H 0 than sodium perborate. However, coated perhydrates of the pyroor tripolyphosphates are also usable.

The glycerides of esteroidally bonded fatty acid or hydroxy fatty acid radicals present, which serve as coating materials and are insoluble in the detergent solution, may contain 8 to 26, preferably 10 to 24, and especially 16 to 18 carbon atoms.

The glycerides that are usable according to the invention include the triglycerides. Natural triglycerides can be used if they have the necessary fusion points and the other physical properties that may be desirable.

These triglycerides can be separated from natural triglycerides, after directed or undirected re-esterification, if desired; however, hydrogenated natural or entirely synthetic triglycerides can also be used. Examples are hydrogenated tallow, hydrogenated castor oil, hydrogenated rape oil, hydrogenated fish oils, etc.

In addition to the triglycerides, monoand diglycerides are also usable. They can be prepared in a prior-art manner from the natural triglycerides or from the fatty acids obtained therefrom.

The mixed esters serving according to the invention as coating substances can be manufactured, for example, by direct esterification of the starting materials (glycerin, higher monocarboxylic acids or lower hydroxymonocarboxylic acids, and dicarboxylic acids), the carboxylic acids, especially the dior polyearboxylic acids, being used preferably in the form of their anhydrides. However, monoor diglyerides containing monocarboxylic acid radicals can be reacted with the dior polycarboxylic acids or their anhydrides. It is expedient to use diand polycarboxylic acids in no more than such an amount that no more than one free carboxyl group is present in the end product for each glycerin radical. Preferably, diand polycarboxylic acids are used in small amounts so that two or more plyceride radicals are coupled together by one dior polycarboxylic acid radical. Compounds of high molecular weight such as these, which can be obtained from monoglycerides and dicarboxylic acids, contain, for example, one dicarboxylic acid radical per glycerin radical.

Depending on the quantity ratio of the esterification components and the time of esterification, the end products may contain certain amounts of free carboxyl groups, but no more than an amount corresponding to an acid number of about 50. When equivalent quantities of glycerin and carboxylic acids or their anhydrides are used, it is easily possible to perform the esterification to acid numbers lower than 30 and preferably lower than 15. If desired, products can even be made with acid numbers ranging from 0 to 5.

According to the invention, a plurality of these various types of glycerin esters can serve simultaneously as coating materials. If, for example, mixed esters of high and, if desired, low fatty acids or hydroxyfatty acids, glycerin and dior polycarboxylic acids are used, mono-, dior triglycerides containing at least one fatty acid or hydroxyfatty acid radical with 8 to 26 carbon atoms, or, if desired, fatty or hydroxyfatty acid radicals with 2 to 7 carbon atoms, but no dior polycarboxylic acid radicals, may be present in these mixed esters, depending on the process used in their manufacture and the quantity ratio of the components. Such glycerides can form, for example, during the direct esterification of mixtures of carboxylic acids and glycerin, the possibility of the formation of these glycerides increasing as the dior polycarboxylic acid content decreases. Such mixtures are usable according to the invention, while the amount of the mixed esters containing dior polycarboxylic acid can amount to at least 50 percent by weight of all of the coating material.

The coated per compounds can be manufactured in various ways. In has proven advantageous to bring the solid per compounds in the powdered to granular state into contact with the coating materials in the liquid state, so that the coating materials flow around in the per compounds, whereupon the coating materials are transformed to the solid state. The coating materials are also applied in the fused state or in the form of a solution in an appropriate organic solvent and sprayed onto the solid per compounds while the latter are in motion. The particles of the fused coating materials solidify as soon as they contact the colder particles of the per compounds; in fact, it is recommendable to chill these particles, which can be done by means of a cool air stream, for example. If the coating materials are applied in the form of a solution in appropriate organic solvents, they solidify as the solvent evaporates, assuming that the working temperatures are below the melting point of the fatty substance used. The evaporation of the solvent can be promoted by a stream of gas.

In the manufacture of some coated per compounds, different coating materials are also applied in succession, in which case the quantity of the coating material first applied does not need to suffice for the achievement of a satisfactory degree of coating. One of these coating materials may consist of a mono-, dior triglyceride which contains no dicarboxylic acid radicals. Mixed glycerides have proven to be a good supplemental coating material when they have in the molecule at least one fatty acid or hydroxyfatty acid radical with 8 to 26 carbon atoms and at least one fatty acid or hydroxyfatty acid radical with 2 to 7 carbon atoms. The quantity of these supplemental mono-, dior triglycerides can amount to as much as 50 percent of the total weight of the coating material.

The oxidant content of the detergents and washing adjuvants of the invention can be equivalent to 0.3 to 7.5, and preferably 0.7 to 3 weight percent of active oxygen, based on the detergent or saponaceous components in the case of detergents and upon the carrier, i.e., nonsaponaceous or non-detersive compounds in the case of the washing adjuvants; this quantity representing the sum of the quantities of active oxygen and active chlorine present, regardless of the fact that active chlorine and active oxygen partially destroy one another when the detergent or washing adjuvant is used. The amounts of active chlorine and active oxygen are to be such that the amount of active oxygen present corresponds to at least two thirds of the amount theoretically necessary for the complete destruction of the active chlorine, and preferably at least equal to that amount. The amount of active oxygen, however, can be greater, and may amount, for example, to one to five times the equivalent quantity of the active chlorine present.

The total quantity of the oxidants present in the bleaching detergents and washing adjuvants according to the invention may be substantially larger. The highest achieva-ble total oxidant contents, expressed in weight percent of active oxygen, in mixtures per se of active chlorine carriers and coated perborate, depends substantially only on the active chlorine content of the carrier and on the ratio in which the two components are mixed. Frequently it is not mixtures of the two oxidants alone that are used, but preparations which also contain fillers or other additives desired in washing and bleaching. Preparations of this kind generally consist of up to a maximum of 75 weight percent, and preferably no more than up to 50 weight percent of the mixture of the two oxidants. The same quantities may also be used in the case of bleachmg detergents within the scope of this invention.

Furthermore, the detergents and washing adjuvants according to the invention can also contain the usual additives, such as surface-active substances, alkalinely and/or neutrally reacting salts, complex formers, dirt carriers, and substances for increasing or decreasing sudslng capacity, all of which are well known in the art.

The surface-active substances may be of an anionic, non-ionic or amphoteric nature, and cationic substances may be present together with them. All these surfaceactive substances contain in the molecule an aliphatic hydrocarbon radical with 8 to 20, preferably 10 to 18, and especially 12 to 1-6, carbon atoms.

The anionic surface-active substances include the alkali soaps derived from saturated or unsaturated fatty acids.

Of especial practical importance are the synthetic anionic products of the sulfate or sulfonate type, such as alkylbenzenesulfonates or fatty alcohol sulfates.

The surface-active substances that can be used according to the invention also include compounds in which the hydrophobic hydrocarbon radical and the water-solubilizing group, particularly the anionic carboxylate, sulfate or sulfonate group, are coupled to one another by oxygen, nitrogen or sulfur, or by a radical containing oxygen, nitrogen or sulfur.

The following are enumerated as examples of such compounds: fatty acid esters or fatty alcohol ethers of oxyethanesulfonic acid, and of the oxypropanesulfonic acids; the corresponding derivatives of dioxypropanesulfonic acid are also referred to as alkylglyceryl ether sulfonates in one case and as fatty acid glycerin ester sulfonates in the other; also, those of aminosulfonic acids or aminocarboxylic acids, especially those of aminoethanesulfonic acid, or of fatty acid amides derived from glyceride or sarcosine. This group of surface-active substances includes also sulfatized fatty acid alkylolamides or sulfatized products of the addition of 1 to 5, and preferably 2 to 3, mols of ethylene oxide onto fatty alcohols, mercaptans, alkylphenols, alkylthiophenols, fatty acld amides, all of which are well known in the art.

The biologically degradable salts of a-sulfofatty ac1ds with to 24, preferably 10 to 18, carbon atoms 1n the molecule, or their products which have been esterified at the carboxyl group with monovalent or polyvalent alcohols containing 1 to 10, and preferably 1 to 4, carbon atoms, can also be used as anionic surface-actlve substances.

The amphoteric surface-active substances 1nclude, for example, N-alkyl derivatives of the above-named ammocarboxylic or aminosulfonic acids; the nitrogen atoms may also be of a tertiary or quaternary nature.

Examples of non-ionic surface-active substances are the products formed by adding ethylene oxide onto fatty alcohols or alkylphenols, fatty acids, fatty ac1d amides, fatty acid alkylolamides, alkylsulfonic acid or alkylbenzenesulfonic acid amides or alkylolamides, partial ethers of fatty alcohols or partial esters of fatty acids with polyvalent alcohols. They include also partial ethers or partial esters derived from glycerin or from the polyglycerins, such as those obtained, for example, by adding glycide onto the corresponding fatty alcohols or fatty acids.

The non-ionic surface-active substances to be used according to the invention, however, also include those in which the hydrophobic organic compounds having a reactive hydrogen atom have first been made to react with higher alkylene, such as propylene oxide or butylene oxide, and then ethylene oxide has been added on until water-solubility is achieved. It is also possible to reverse the procedure, and first to make the starting materials water-soluble by adding on sufficient amounts of ethylene oxide, and then adding on limited amounts of propylene oxide, that is, not so much that the compounds are made insoluble in water. Products manufactured in this manner are characterized by an especially low sudsing capacity.

All these surface-active substances can be combined with one another in many different ways in the bleaching detergents or washing adjuvants according to the invention.

The cleansing and sudsing properties of the preparations of the invention can be substantially influenced by variously combining different anionic and/or non-ionic surface-active substances. Particularly the sudsing properties can be varied. For example, combinations of surface-active sulfonates and/or sulfates, soap and non-ionic surface-active substances are suitable as low-sudsing wahing machine detergents, especially when the soaps or the free fatty acids corresponding thereto contain, in the prior art manner, more than 50 percent of their weight in saturated fatty acid radicals having 16 or more carbon atoms; fatty acid radicals having 20 and more carbon atoms, especially those having 20 to 26 carbon atoms, may also be present.

Otherwise, the detergents and washing adjuvants according to the invention are not to contain any uncoated substances which consume active chlorine in storage or when the detergent or adjuvants are used.

The invention is applicable both to detergents and to washing adjuvants. Detergents here refers to products which contain all of the additives necessary for the achievement of the desired results in washing, Whereas the washing adjuvants are to be used in a washing process in combination with a detergent or with components of detergents. B combined use in a washing process is meant the use of such adjuvants alone, or together with other components of detergents, before or after the main washing procedure in a multiple-step washing process, as for example, in soaking clothes, in preliminary washing, or in rinsing, and also their use together with a detergent in the main washing procedure in a single-step or multiple step washing process. Such washing adjuvants include, for example, soaking or preliminary washing agents, rinsing agents, and, lastly, bleaching and disinfecting agents.

Detergents and washing adjuvants differ generally in the amount of the surface-active substances that may be present. While the surface-active substances in detergents may generally amount to at least 7.5 percent and preferably at least 10 percent, and up to around 60 percent, though preferably up to around 45 percent, of the total detergent, the washing adjuvants generally contain 0 to 7.5 percent, and preferably 1 to 5 percent, of surfaceactive substances.

Another difference between the various preparations may also lie in the pH value which they impart to their aqueous solutions. Bleaches which are used in combination with other alkalinely reacting substances may give pH values in 1 percent aqueous solutions ranging from 6 to 8.5, and preferabl ranging from 7 to 8. Preliminary washing agents or rinsing agents to be used at temperatures above C. are, like the principal detergents, generally adjusted alkalinely, i.e., the pH values of their 1 percent aqueous solutions range from 9 to 12 and preferably from 9.5 to 11.5. The adjustment of the pH factor is performed by suitably combining the various neutrally or alkalinely reacting products.

The chief neutrally reacting salt is sodium sulfate, which is capable of improving the surface-active properties of the combination according to the invention; it can be replaced wholly or partially by non-surface-active, neutrally reacting organic salts, such as non-surface-active aryl sulfonates like benzene, toluene or naphthaline sulfonates.

The alkali carbonates or alkali bicarbonates, the watersoluble alkali silicates, alkai orthophosphates, etc., are examples of washing alkalies.

The combination according to the invention of active chlorine and coated per compounds can also be used together with the anhydrous alkali or alkaline earth phosphates of the prior art. The anhydrous phosphates include primarily pyrophosphates, polyphosphates and metaphosphates, the tripolyphosphates and tetrapolyphosphates being particularly important. Whereas pyrophosphates and polyphosphates react alkalinely, so that, when used alone in boiling-type detergents, they are capable of supplying the necessary alkalinity, the reacting of the metaphosphates is weakly acid, so that they are used either with alkalinely reacting substances or they are mixed into preparations having a weakly alkaline to Weakly acid reaction.

Furthermore, the preparations according to the invention additionally contain the substances customarily incorporated into detergents. To improve the dirt carrying capacity, water-soluble colloids, usually of an organic nature, are added, such as the water-soluble alkali, or in some cases, alkaline earth salts of polymeric carboxylic acids, glue, gelatine, similar salts of ether carboxylic acids or ether sulfonic acids of starch or of cellulose, or similar salts of acid sulfuric acid esters of celluose or of starch.

To improve sudsing capacity, the fatty acid amides have been primarily used; there may be substituted on the nitrogen with alkyl or alkylol radicals having no more than 6 carbon atoms per radical. Also used are products of the addition of ethylene oxide onto these unsubstituted or substituted fatty acid amides.

The salts present in the preparations according to the invention can be derived from inorganic or organic bases such as the organic amines, but especially sodium or potassium.

The advantage achieved by the invention consists primarily in the possibility of bleaching textiles at low temperatures by means of active chlorine, without having to fear damage to the textiles by chlorine in the event of a temperature rise. If, after th destruction of the active chlorine that has not been consumed in the bleaching,

any active oxygen that is still present functions as an additional oxygen bleaching agent, and bleaching can take place primarily at temperatures above 75 C., and preferably at 90* to 100 C.; the combination of chlorine and oxygen bleaching often proves advantageous, especially in the case of spots due to organic colorants which are of such frequent occurrence in the case of textiles. It is therefore recommendable to use coating substances which release the per compounds at no higher than 85 C., preferably at no higher than 75 C., and advantageously at 65 C.

In order to achieve the effect that is being sought according to the invention, and do so in the most economic manner possible, it is recommendable to use thoroughly coated per compounds. This may be assured by using a plurality of coating layers on the per compound. If any uncoated or incompletely coated particles of per con pounds are present, they react with the active chlorine, sometimes while they are still in storage, and eventually when the preparation is mixed into Water. The action of the preparations according to the invention is not impaired basically thereby, providing active chlorine remains available after the mutual destruction of equivalent quantities of active chlorine and uncoated per compounds. It is recommendable, however, to use per compounds which are coated to at least 70 percent and preferably to at least 85 percent.

Since coating percentages of 90 to 98 percent are easily achieved, there is nothing in the way of using per compounds with coatings as perfect as this.

The amount of coating substance depends to some extent on the grain size of the per compounds. The grain size of the coated per compounds should best be about the same as the average grain size of the other bleaching and detergent components in which they are contained. This size ranges from 0.2 to 3.2 mm., and preferably from 0.3 to 2.0 -mm., and there should be practically no dust-like particles of a grain size below 0.1 mm., and no large particles of a grain size above 3.5 mm. In this range of grain sizes, the amount of coating substances necessary for the achievement of a satisfactorily coated perborate can range from 15 to 50 weight percent, and preferably from 25 to 40 weight percent, based on the oxygen-yielding compound, e.g., perborate, the products of finer granularity generally requiring more coating substance than coarser ones.

The coating percentage of coated per compounds is determined by the following standard: About g. of the coated per compound is extracted with chloroform in a Soxhlet-type extraction apparatus. After the extraction has ended and the chloroform has been evaporated, the coating substance remains as a residue. The percentage H of coating material is calculated from the amount of residue and the initial weight.

To determine the quantity of uncoated or incompletely coated perborate, 5.00 g. of the coated perborate is suspended in 500 ml. of water; the suspension is let stand for one hours at room temperature with frequent gentle agitation. The residue is removed by filtration, the filter is Washed and the filtrate is made up to 1 liter. 50 ml. thereof are titrated with 0.1 N KMnO solution. From the amount consumed (a=ml. 0.1 N KMnO solution) it is possible to compute the percentage A of uncoated or incompletely coated perborate on the basis of the formula coating U, and represents the percentage of completely coated perborate.

EXAMPLES In the following examples, unless otherwise expressly stated, such amounts of coated perborate were used in each case that oxidation-equivalent quantities of active chlorine and active oxygen were present, i.e., the quantities of the two oxidants were such that, if simultaneously dissolved in water, they would have entirely destroyed one another. Each perborate that is listed in Table II at the end of the examples can be incorporated into every one of the detergents described in the examples. Since the quantities of the coated perborates to be used depend on their active oxygen content, these quantities are not stated by weight in any example, since they are positively determined in any case by the amount of active chlorine present and the active oxygen content of the coated perborate.

The last column of Table 11 states the detergent described in the examples into which the particular coated penborate was incorporated for the performance of practical experiments.

The terms.active chlorine and available active chlorine here signify the chlorine contents as determined by iodometric titration. Since according to the formula two atoms of iodine have been made available for each atom of active chlorine present, the active chlorine content determined by iodometric titration is twice as high as computed on the basis of the formula for the substance.

Example I A coated sodiumperborate is mixed with 43 parts by weight of a mixture of 1 part by weight of technical calcium hypochlorite containing sodium chloride (36 weight percent active chlorine) and 4 parts of sodium tripolyphosphate, and corresponds to Examples Ic-i and Ic-ii below.

To demonstrate the action of the invented preparation, which can be used by itself or with common preliminary Washing substances or detergents as a bleaching or disinfecting agent, in comparison with those which contain active chlorine alone or active chlorine and non-coated perborate, the following experiments are performed.

The following are put each in a liter of water at 20 C.:

(Ia) A mixture of calcium hypochlorite and sodium tripolyphosphate (lb) A mixture of calcium hypochlorite and sodium tripolyphosphate plus uncoated sodium perborate (Ic) A mixture according to the invention (containing coated sodium perborate according to Table H) i. Serial No. 2 ii. Serial No. 9

The quantities of composition Ia, Ib and Ic dissolved in the water are of such proportion that the active chlorine concentration immediately after the dissolution of the products amount to 250 mg. per litter. In the case of I'll Diture lb, the amount of uncoated perborate is made such that oxidation-equivalent quantities of active chlorine and active oxygen are present. Immediately after these products are put into the water, the mixtures are gradually heated all together in a water bath, with gentle agitation, from the initial temperature (20 C.) to 72 C. in the course of about 50 minutes.'From time to time, specimens are taken, cooled to 20 C. with the exclusion of air, and titrated with thiosulfate after the addition of potassium iodide and acidification in the usual manner. The total oxidation value arrived at in each case (the sum of all active oxidants present) is calculated as active chlorine. In the case of products Ia, the active chlorine content of 250 mg./l. at the beginning of the test drops within 50 minutes to 181 mg./l. at 70 C. In product I'b, after only 11 minutes, at a temperature of 22 C., an active chlorine of only 16 mg./l. is measured; after 18 minutes at 26 C., no more oxidant can be detected: the active chlorine and active oxygen destroy one another. In the case of preparations Ic-i and Ic-ii, the active chlorine content after 30 minutes, at a temperature of 45 C., is still 145 and nrg./l. (for mixtures containing in one case borate with coatings as per Table II, Serial No. 2, and in the other case, for borates with coating No. 9, respectively); after another 7 minutes in which a temperature of 55 C. has been reached, the active chlorine content drops to and 3 m./l. Fifty minutes after the beginning of the test, a temperature of 66 C. has been reached in the one case and 68 C. in the other, and no more oxidant is to be detected.

As it can be seen, the active chlorine content of the hypochlorite solution decreases but gradually, and even at temperatures above 50 C., it is still so high that damage to textile fibers is inevitable. With mixtures of hypochlorite and uncoated perborate, the break-down of the oxidants immediately after the preparation is put into the water is completed so rapidly that this mixture is practically unusable for bleaching. Only in the case of the mixture of hypochlorite and coated perborate does a spontaneous decrease of the oxidation value occur above 40 C.

(Id) A coated sodium perborate as described in Serial No. 11 of Table II is mixed with 43 parts by weight of a mixture of 1 part by weight of technical calcium hypochlorite containing sodium chloride (36 weight percent active chlorine) and 4 parts of sodium tripolyphosphate. The results obtained are substantially the same as those for Example Ic, when this composition is dissolved in a liter of water at 20 C. and heated.

Example II For the manufacture of a bleaching detergent for washing machine use having the composition given below, a powder obtained in the common manner by spray drying and containing all components except the potassium dichlorisocyanurate and the coated perborate is mixed with these two bleaching agents. The salts present in the detergent are sodium salts unless otherwise stated.

Myristic acid 8 Arachinic and behenic acid 43 Palmitic and stearic acid 47 Unsaturated fatty acid 2 45 weight percent tripolyphosphate; 10 weight percent water glass; 7.8 weight percent potassium dichlorisocyanurate; (59

weight percent active chlorine); Balance: Coated sodium perborate, as per Table II, Ser.

No. 2, sulfate and water.

A similar composition is also prepared using the same detergent ingredients with the exception that cooled sodium perborate as per Table II, Ser. No. 9, and sodium sulfate are used to make up the balance.

To demonstate the action of the detergent of the invention in comparison with those which contain no perborate or non-coated perborate, the experiments described in Example I are performed on three detergents which differ from the above-stated compositions as follows:

(11a) The coated sodium perborate is replaced by the corresponding amount of sodium sulfate.

(11b) The coated perborate is replaced by the equivalent amount of uncoated perborate; furthermore, the detergent contains a little more sodium sulfate (to bring up to 100 percent).

(He) Detergent of Example II, coated sodium perborate as per Table II,

i-2. Serial No. 2 ii-9. Serial No. 9.

Such quantities of these three detergents are dissolved each in one liter of water at 20 C., so that the active chlorine concentration amounts to 250 mg./l. Then these solutions, as described in Example I, are heated within about one hour up to approximately C. In product Ila, the active chlorine content drops by the end of the test to 94 mg./l., while in product IIb, the mutual destruction of active chlorine and active oxygen has ended after about 15 minutes when a temperature of about 25 C. has been reached, In the case of the detergents IIci2 and IIcii-9, the oxidation value drops to and mg., respectively, of active chlorine per liter, after 30 minutes, and after temperatures of 42 and 40 C. are reached. After another 7 and 10 minutes, respectively, when temperatures of 48 and 50 C. are reached, the oxidation value amounts to 57 and 48 mg./l. respectively, then dropping rapidly to 15 mg./l. of active chlorine. This Oxidation value, which remains constant up to the 80 C. temperature, is not to be attributed to the presence of active chlorine, but to unconsumed perborate, because the active chlorine is destroyed not only by reaction with the perborate, but also undergoes an increasing self-destruction as the temperature rises.

EXAMPLES 110-11 The procedure of Example He is repeated several times as Examples IId, IIe, IIf, Hg, and 11b, in which the coated perborates in Table II, designated Serial Nos. 1, 8, 10, 11 and 12, are substituted respectively in such examples for the coated perborate of Example 11c, and substantially the same results are obtained as is the case with Example IIc.

Example III (IIIa) A low-sudsing detergent intended primarily for use in washing machines, which can be used as a boiling detergent with a bleaching action, is prepared having the following composition, the salt-like components again being in the form of sodium salts:

4.0 weight percent alkylbenzenesulfonate (as in Ex. ll);

10.0 weight percent of an addition product of 9 mols of ethylene oxide on 1 mol of a coconut fatty alcohol;

1.5 weight percent n-hexadecanol;

35.0 weight percent tripolyphosphate;

6.0 weight percent water glass;

0.5 weight percent carboxymethylcellulose;

7.7 weight percent potassium dichlorisocyanurate (59 weight percent active chlorine);

Balance: Coated sodium perborate, as per Table II, Serial No. 3, sodium sulfate and water.

EXAMPLES IIIb-j The procedure of Example IIIa is repeated several times and designated Examples IIIb, IIIc, IIId, IIIc, IIIf, IIIg, IIIh, 111i and 111i, in which the sodium perborate used therein is substituted by a perborate, as defined in Table II, Serial Nos. 4, 5, 6, 8, 9, 10, 11, 12 and 13, corresponding respectively to the designated examples. When all of the preparations of Example III are evaluated in the same manner as the compositions of Example IIc, substantially the same results are obtained as those of Example IIc.

Example IV (IVa) A product of the following composition is prepared as a substance for laundry disinfection:

5 weight percent alkylbenzenesulfonate (like Example 40 weight percent sodium tripolyphosphate;

5 weight percent Na O-3.3 SiO 18.1 weight percent tetrachlormalonamide;

Balance: Coated sodium perborate, as per Table II, Serial nurate and coated perborate (coating substances 7 and No. 3, sodium sulfate and water. 12) were used:

TABLE I Detergent designation V V V V V V V a-7 a-12 13-7 13-12 (2-7 c-12 d-7 d-l2 Oxidants:

Wt. percent sodium dichlorisocyanurate 7. 3 7. 3 7. 4 7. 4 7. 6 7. 6 7. 8 7.8 Wt. percent coated sodium lperbtor zitefinfl 13.2 13.2 10.8 10.8 0.6, 9.6 7.1 7.1 T of coated sodium or orae a e 21 No i"; 7 12 7 12 7 12 7 12 Quantity of actiwfietiloxygen extpressed as f a ercenta e o e amoun necessary or a co inplete d estruction oi the active chlrine 81 81 64 64 56 56 41 41 (IVb) A similar detergent composition is prepared with the above ingredients, with the exception that a coated sodium perborate according to the Table II, Serial No. 12, and sodium sulfate is substituted for the balance of sodium perborate and sodium sulfate.

The product of Examples III and IV is used m a concentration of 6.25 g./l. It is dissolved in cold water, and laundry is placed in the solution and is left there for 15 to 30 minutes with occasional stirring. It is desirable to heat the solution to 35 C. to 45 C., and to keep the temperature at that level for 10 to minutes. Then it is heated rapidly to 80 C. When products of Serial Nos. 3 and 12 in Table II are used as the coated perborate, the oxidation value of the solution drops from an initial 200 mg./l. to 89 and 80 mg./l. of active chlorine, respectively, at 60 C; at 80 C., the active chlorine is totally destroyed.

EXAMPLES IVc, a, AND e The procedure of Examples IVa and Nb is repeated several times and designated IVc, IVd, and We, with the exception that the sodium perborate used in the two previous examples is substituted by sodium perborates defined in Table II, Serial Nos. 6, 9 and 13, respectively, for the designated examples, and substantially the same results are obtained, as is the case with Examples IVa and IVb.

Example V Using different amounts of coated sodium perborate (Table II, Serial Nos. 7 and 12) and sodium dichlorisocyanurate (64.1 weight percent active chlorine), eight different detergents of the following composition are prepared, sodium being used as a cation of the salt-like compositions, unless otherwise indicated:

10 weight percent u-sulfofatty acid ester salts (sulfonation products of the methyl ester formed from the hydrogenated mixture of equal weight parts of coconut and tallow fatty acids);

5 weight percent soap (made from the hydrogenated mixture of weight percent coconut fatty acid and 70 weight percent tallow fatty acid);

weight percent pyrophosphate;

5 weight percent magnesium silicate;

7 weight percent water glass;

1 weight percent carboxymethylcellulose;

Balance: Mixture of varying amounts of sodium dichlorisocyanurate and coated perborate, optical brighteners, perfume, sodium sulfate and water.

The following quantities of sodium dichloroisocya- Aqueous solutions of these detergents are heated as in Example I, their concentration being made such that the initial active chlorine concentration in all cases amounts to 250 mg./l. When a temperature of 50 C. is reached, the active chlorine concentrations of the solutions fall to about 158 to 168 mg./l. Upon further heating, the active chlorine concentrations drop still further; in solutions of detergents Va-7, Va-12, Vb-7 and Vb-l2, no more oxidant is detected at 60 C, While in the solutions of detergents Vc-7, Vc-lZ, Vd-7 and Vd12, 28, 30, 54 and 50 mg./l. of active chlorine are found when C. is reached. An active chlorine content of about 50 mg./l. at 80 C. is to be considered as the point of commencement of fiber damage; mixtures with the mrformance of mixtures Vc-7 and Vc-12, and especially of mixtures Va-7, Va-12, Vb-7 and Vb-12 are therefore preferred.

EXAMPLES Vc, d, e AND 13 The procedure of Example Va-7 is repeated several times and designated Examples Vc, Vd, Ve and Vf, with the exception that coated sodium perborate used therein is substituted by sodium perborates described in Table II, Serial Nos. 8, 9, 10 and 11, respectively, with regard to each designated example, and substantially the same results are obtained, as is the case with Example Va-7.

Example VI If the active chlorine compounds contained in the preparations of the foregoing examples are replaced by the equivalent quantity of a chlorinated condensation product after American Patent 3,104,260, made from 2 mols of urea and 3 mols of acetone (67 percent active chlorine), the preparations thereby obtained can be used with the same result as those described in the examples.

Although the detergents and washing adjuvants described in the examples contain active chlorine and active oxygen usually in oxidation-equivalent quantities, the active oxygen can also be present in larger quantities. In experiments with detergents and washing adjuvants whose composition differs from those given in the examples only in that the active oxygen amounts to up to five times, and prefer-ably up to three times the equivalent amount of active chlorine, it has'been found that the active oxygen still present after the destruction of the active chlorine has a bleaching action, too, at correspondingly high temperatures above 75 C. and preferably of C. and up, so that a combined chlorine and oxygen bleach is achieved.

The following table contains a listing of the properties of coated perborates such as those used for the manufacture of detergents and washing adjuvants of the composition given in the examples. Those coating substances are preferred Whose melting range, softness and bending strength lie within the stated ranges. In addition to these mixed esters, an esterification product of 1 mol of glycerin, 0.75 mol of behenic acid and 0.75 mol of phthalic acid anhydride (M.P. =6061 C., penetrometric value: 0.6 mm.; ultimate bending strength 170 g./mm. proves usable as a coating material for per-oxygen compounds.

Also coating substances may be used which diifer from those described in that the stearic acid or behenic acid contained therein is partially or entirely replaced by arachinic acid or by hardened peanut oil, rape oil or fish oil fatty acids.

16 drogen and oxygen atoms and having 2 to 10 carbon atoms, phthalic acid radicals and mixtures thereof.

6. The coated per-oxygen compound of claim 1, in

TABLE II.IROPERTIES OF COATED SODIUM PERBORA'IES USED ACCORDING TO THE INVENTION, AND OF THE COATING SUBSTANCES CONTAINED THEREIN [Tliccoated perborates described herein, like the detergents and washing adiuvants described In the examples, dilfer slightly irom one another in grain- SIZO make up; in all products (coated perborates, detergents and washing adjuvants) the grain sizes range from 0.3 to 0.6 mm.]

Ultimate Penetrobending metric strength Wt. Wt. Melting value per DIN Degree percent percent point, per DGF 51030, of coating active Used in composition No. Description C. in mm. g./mm. coating material oxygen of Ex. No.

l Hardeed castor oil 83.5 0.7 230 86 46 5.5 I, II. 2 Stearic acid triglyceride 58.5 0.9 230 90 7.1 II. 3 Mixed triglyceride containing:

1 mol hardened tallow fatty acid 2 mols acetic acid 54 2 9 150 93 33 6. 8 III, IV. 4 Ialmitinic acid monoglyceride- 54 1. S 183 76 27 0. 7 III. 5 Stearic acid monoglyceride 58 1.5 180 82 33 6. 7 III. 6.--. Esterification product of 1 mol glycerin 5155 1. 2 137 89 20 7. 2 III, IV. 7 Combination of:

50% ester of No. 2 as inner coating 58. 5 0 9 230 l 93 6 8 v ester of No. 3 as outer coating 54 2 9 150 I 8 Mixed ester of:

1 mol glycerin 1 mol stearic acid 0.8 180 87 35 0. 4 II, III and V. 9 Mixed ester of:

1 mol glycerin 1 mol behenic acid. 61 0. 9 200 99 35 0. 6 I, II, III, IV and V.

0.5 mol phthalic acid 10 Mixed ester of:

1 mol glycerin 0.5 mol behenic acid 1 mol phthalic acid 11 Mixed ester of:

1 mol glycerin 0.5 mol behenic acid.

0.5 mol phthalic acid 12 Combination oi:

50% ester of No. 8 as inner coating- 50% ester oi N o. 3 as outer coating- 13 Mixed ester ol:

1 mol glycerin 0.25 molbenzoic acid..

II, III and V.

I, II, III and V.

What is claimed is:

1. A coated per-oxygen compound, said coating being water-insoluble at room temperature and consisting essentially of an ester of glycerin and at least one member selected from the group consisting of water-insoluble monocarboxylic acids containing 8 to 26 carbon atoms,

water-insoluble hydroxy-monocarboxylic acids containing 40 8 to 26 carbon atoms, aliphatic polycarboxylic acids containing only carbon, hydrogen and oxygen atoms and having 2 to 10 carbon atoms, phthalic acid and mixtures thereof.

2. The coated per-oxygen compound of claim 1, in 50 which contain in the molecule at least one member selected from the group consisting of radicals of monocarboxylic acids and hydroXy-monocarboxylic acids containing 2-7 carbon atoms and at least one member selected from the group consisting of radicals of monocarboxylic acids and hydroxy-monocarboxylic acids containing 8 to 26 carbon atoms.

5. The coated per-oxygen compound of claim 1, wherein said coating consists essentially of at least 50 percent by weight of a mixed glyceride containing for each glycerin radical at least one member selected from the group consisting of monocarboxylic acid and hydroxy-monocarboxylic acid radicals containing 8 to 26 carbon atoms and at least 0.25 percent of its weight, at least one acid radical selected from the group consisting of aliphatic polycarboxylic acid radicals containing only carbon, hy-

40 which said coating contains additional glycerides having acid radicals selected from at least one member of the group consisting of monocarboxylic acid and hydroxymonocarboxylic acid radicals containing two to seven carbon atoms in a quantity of preferably no more than one radical per mol glycerin.

7. The coated per-oxygen compound of claim 1, wherein the coating material consists essentially of up to 50 percent of at least one member selected from the group consisting of monoglycerides, diglycerides, triglycerides and mixtures thereof having in their molecules monocarboxylic acid radicals containing 8 to 26 carbon atoms, and acid radicals selected from at least one member of the group consisting of monocarboxylic acid radicals and hydroxycarboxylic acid radicals containing 2 to 7 carbon atoms and mixtures thereof.

8. The coated per-oxygen compound of claim 1, said coating consisting essentially of mixed monocarboxylic glycerides having monocarboxylic acid radicals containing 8 to 26 carbon atoms and being up to at least 50 percent by weight based on said glyceride of a saturated nature.

9. The coated per-oxygen compound of claim 8, in which said fatty acids of said esters have an acid number below 30.

=10. The coated per-oxygen compound of claim '8, in which said fatty acids of said esters have an iodine number below 10.

11. The coated per-oxygen compound of claim 8, in which said fatty acids of said esters have an iodine number below 5.

12. The coated per-oxygen compound of claim 1, in which the coating comprises multiple layers of glycerides.

13. The coated per-oxygen compound of claim 1, where said coating has a bending strength from to 350 g./mm.

14. The coated per-oxygen compound of claim 1, in

1 7 which said per-oxygen compounds are coated to a degree of 70-98% 15. The coated per-oxygen compound of claim 1, wherein said oxygen compound has an average grain size from approximately 0.2 to 3.2 mm. particles of the grain size below 0.1 and above 3.5 mm. being substantially absent, the amount of coating being from 50 to 15 percent of the weight of the coated per-oxygen compounds.

16. A washing adjuvant composition consisting essentially of the coated per-oyxgen compound of claim 1, in combination with an active chlorine compound yielding chlorine in cold water.

17. A bleaching detergent consisting essentially of the coated per-oxygen compound of claim 1, an active chlorine compound yielding chlorine in cold water, and a detergent compatible with the per-oxygen compound and the active chlorine compound.

18. The washing adjuvant composition of claim 16, in which said per-oxygen compound is present in an amount of 1 to times the quantity theoretically necessary for reaction with the amount of active chlorine present.

19. The washing 'adjuvant composition of claim 16, where said active chlorine compounds and coated perborates expressed as oxidants are present in an amount 18 of from 0.3 to 7.5 weight percent calculated as active oxygen.

20. The bleaching detergent of claim 17, wherein said per-oxygen compounds are present in amounts to one to five times the quantity theoretically necessary for reaction with the amount of active chlorine present.

21. The bleaching detergent of claim 17, where said chlorine compounds and coated per-borates amount to 75 percent to percent of the total.

22. The bleaching detergent of claim 17, where said active chlorine compounds and coated perborates expressed as oxidants are present in amounts of from 0.3 to 7.5 weight percent calculated as active oxygen.

References Cited UNITED STATES PATENTS 3,112,274 11/1963 Morgenthaler et al. 202--99