US3359207A

US3359207A - Chlorine-stable detergent compositions and process for the preparation thereof

Info

Publication number: US3359207A
Application number: US465197A
Authority: US
Inventors: Thomas M Kaneko; Irving R Schmolka
Original assignee: Wyandotte Chemicals Corp
Current assignee: Wyandotte Chemicals Corp
Priority date: 1965-06-18
Filing date: 1965-06-18
Publication date: 1967-12-19
Anticipated expiration: 1984-12-19
Also published as: BE682739A; GB1107166A; NL132419C; NL6608107A

Description

3,359,207 CHLORINE-STABLE DETERGENT COMPOSI- TIONS AND PROCESS FOR THE PREPARA- TION THEREOF Thomas M. Kaneko, Trenton, and Irving R. Schmolka, Grosse Ile, Mich assignors to Wyandotte Chemicals Corporation, Wyandotte, Mich a corporation of Filed June 18, 1965, Ser. No. 465,197 14 Claims. (Cl. 252-99) Michigan No Drawing.

ABSTRACT OF THE DISCLOSURE Dry, free-flowing chlorine-stable detergent compositions comprising an alkaline condensed phosphate, a hydrated sodium metasilicate, an active chlorine-containing compound, a nonionic surfactant, and water are prepared. The compositions are prepared by sequentially mixing the above ingredients as follows: (1) adding an aqueous solution of a nonionic surfactant to an alkaline condensed phosphate whereby simultaneous hydration of the condensed phosphate and absorption of the surfactant occurs, (2) adding a hydrated sodium metasilicate to the hydrated condensed phosphate from step (1), (3) reducing the size of the mixture resulting from step (2), and (4) adding an active chlorine-containing compound to the mixture from step (3).

However, heretofore, much difiiculty has accompanied the preparation of detergent compositions comprising both an active chlorine-containing compound and a nonionic surfactant because of the interaction which generally occurs between the two. This interaction generally results in discoloration-and degradation of the detergent composition with an accompanying loss in the available chlorine content of the composition. Since a nonionic surfactant possesses wetting properties and an active chlorine compound possesses bleaching, cleaning and sanitizing properties, it is; desirable to have both compounds present in detergent compositions.

Several attempts have been made to prepare a detergent composition containing both a chlorine compound and a nonionic surfactant but heretofore all have failed for one reason or another. For example, US. 2,895,916 relates to a process for the preparation of detergent compositions containing an active chlorine compound. Disclosed is use of a nonionic surfactant in the preparationof the mpositions. It has now been found that although detergent compositions containing an active chlorine compound and a nonionic surfactant may be prepared according to process of this patent, the compositions are not stable with respect to the active chlorine content; that is, within a very short time the starting available chlorine content decreases to such an extent that for all practical purposes the detergent compositions are chlorine-free.

Now, in aqaordanc'e with this invention, chlorinestable detergent compositions containing nonionic sur- Examiner 5 3,359,207 Patented Dec. 19, 1967 ice factants are prepared by a process requiring specific ingredients sequentially admixed in the following manner:

(a) adding an aqueous solution of a nonionic surfactant to an alkaline condensed phosphate selected from the group consisting of tetrasodium pyrophosphate and mixtures of tetrasodium pyrophosphate and other inorganic salts, said mixtures containing at least 50 percent by weight tetrasodium pyrophosphate, whereby hydration of the condensed phosphate and simultaneous absorption of the surfactant occurs;

(b) adding a hydrated sodium metasilicate to the hydrated condensed phosphate with mixing;

(c) reducing the size of the mixture resulting from (b) to a desired particle size, and

((1) adding an active chlorine-containing compound to the mixture from (c) whereby a dry, free-flowing, granular product is obtained.

As demonstrated hereinafter, if components other than those stated above are employed or if the sequence stated above is not substantially followed, chlorine-stable detergent compositions are not obtained.

The detergent compositions of this invention comprise four ingredients: an alkaline condensed phosphate, a hydrated metasilicate, an active chlorine-containing compound, and a nonionic surfactant.

Tetrasodium pyrophosphate must be employed as part of the alkaline condensed phosphate ingredient of the detergent compositions of this invention. The phosphate ingredient may comprise 100 percent tetrasodium pyrophosphate or it may comprise a mixture of tetrasodium pyrophosphate and inorganic salts providing that at least 50 percent of the mixture is tetrasodium pyrophosphate. Examples of inorganic salts which may be employed in admixture with tetrasodium pyrophosphate include sodium tripolyphosphate, sodium carbonate and sodium sulfate. It has been found, and will be demonstrated hereinafter, that if tetrasodium pyrophosphate is not employed as the phosphate ingredient, either alone or in admixture as stated, chlorine-stable detergent compositions are not obtained. Based on 100 parts of detergent composition, 35 to parts of phosphate ingrediem-may be employed, preferably 50 to 60 parts.

Another ingredient of the detergent compositions of this invention is a hydrated sodium metasilicate. Metasilicates serve several functions in detergent compositions which are particularly useful in machine operations. Besides adding alkalinity to the detergent compositions, they prevent corrosion attack on the washing equipment. Hydrated metasilicates are employed in the preparation of the compositions of this invention since they do not react with nonionic surfactants nor do they promote agglomeration. Thus, problems previously encountered in using silicates and metasilicates along with nonionic surfactants, that is, discoloration and degradation resulting from interaction of the silicate or metasilicate and surfactant and extensive aging and screening periods resulting from agglomeration of the product, are overcome by employing the hydrated metasilicates in accordance with this invention. Based on parts of detergent composition, five to fifteen parts of hydrated metasilicate, preferably ten parts, may be employed. Sodium metasilicate pentahydrate is the preferred hydrated metasilicate primarily because it is commercially available.

Another ingredient of the detergent compositions of this invention is an active chlorine-containing compound. As mentioned above, the active chlorine-containing compound imparts germicidal and bleaching action to the detergent compositions. Active chlorine-containing compounds which may be employed in accordance with this invention include chlorinated trisodium phosphate, trichlorocyanuric acid, sodium salt of dichlorocyanuric acid, potassium salt of dichlorocyanuric acid, sodium hypochlorite and 1,3-dichloro-5,5-dimethylhydantoin. Based on 100 parts of detergent composition, 5 to 25 parts of active chlorine-containing compound may be employed. If chlorinated trisodium phosphate is employed, then from 10 to 25 parts of the chlorine compound is preferred since the amount of chlorine available in chlorinated trisodium phosphate is only 0.325 part per part of compound. Much higher amounts of chlorine are available in the chlorinated cyanuric acids and, therefore, when they are employed, from five to ten parts of chlorine compound is preferred. Generally, the amount of chlorine compound employed will depend upon the intended application of the detergent composition.

The fourth ingredient of the detergent compositions of this invention is a nonionic surfactant. The use of a surfactant in detergent compositions which are to be employed in automatic washing operations is essential to good cleaning and drying since the surfactant serves as a wetting agent. Nonionic surfactants are especially useful in this regard. Not only must the surfactant be a wetting agent, it must also not cause or promote foaming since foaming reduces cleaning efficiency and clogs the machinery. Surfactants which may be employed in the compositions of this invention are generally the polyoxyalkylene adducts of hydrophobic bases wherein the oxygen/carbon atom ratio in the oxyalkylene portion of the molecule is at least about 0.5. Those compositions which are condensed with hydrophobic bases to provide a polyoxyalkylene portion having an oxygen/carbon atom ratio of at least 0.5 include ethylene oxide, butadiene dioxide and glycidol and the like. Ethylene oxide, for example, is condensed with the hydrophobic base in an amount sufiicient to impart water solubility and surface active properties to the molecule being prepared. The exact amount of ethylene oxide condensed with the hydrophobic base will depend upon the chemical characteristics of the base employed and is readily apparent to those of ordinary skill in the art relating to the synthesis of oxyalkylene surfactant condensates.

Typical hydrophobic bases which can be condensed with ethylene oxide in order to prepare nonionic surface active agents include monoand polyalkyl phenols, polyoxypropylene condensed with a base having from about one to six carbon atoms and at least one reactive hydrogen atom, fatty acids, fatty amines, fatty amides, alkyl mercaptans and fatty alcohols. The hydrocarbon ethers such as the benzyl or lower alkyl ether of the polyoxyethylene surfactant condensates are also advantageously employed in the compositions of the invention.

Among the suitable nonionic surfactants are the polyoxyethylene condensates of alkyl phenols having from about six to twenty carbon atoms in the alkyl portion and from about 5 to 30 ethenoxy groups in the polyoxyethylene radical. The alkyl substituent on the aromatic nucleus may be octyl, diamyl, polymerized propylene such as propylene tetramer and trimer, isooctyl and many]. The benzyl ethers of the polyoxyethylene condensates of monoalkyl phenols impart good properties to the compositions of the invention. A typical product corresponds to the formula:

G (oiHio) .cmomon where R is an alkyl group, and n is from about to 30.

Other suitable water-soluble nonionic surfactants are cogeneric mixtures of conjugated polyoxyalkylene compounds containing in their structure at least one hydrophobic oxyalkylene chain in which the oxygen/carbon atom ratio does not exceed about 0.33 and at least one hydrophilic oxyalkylene chain in which the oxygen/carbon atom ratio is not less than about 0.5. Propylene oxide, butylene oxide, amylene oxide and styrene oxide are illustrative of oxyalkylene compounds having an oxygen/ carbon atom ratio not exceeding about 0.33 while ethylene oxide, butadiene dioxide and glycidol, as previously pointed out, are illustrative of oxyalkylene compounds having an oxygen/carbon atom ratio of at least about 0.5. Although the hydrophobic chain has an oxygen/carbon atom ratio not exceeding about 0.33, it is often advantageous to include in this chain a small amount of ethylene oxide, that is, up to about fifteen weight percent, and likewise in the hydrophilic chain which has an oxygen/carbon atom ratio not less than about 0.5, it is often advantageous to include a small amount of propylene oxide or butylene oxide, that is, up to about fifteen weight percent, and the oxygen/carbon atom ratios described herein and in the claims are not intended to preclude such mixtures.

Among the conjugated polyoxyalkylene compounds which can be used in the compositions of the invention are those which correspond to the formula:

wherein Y is the residue of an organic compound having from about one to six carbon atoms and one reactive hydrogen atom, n has an average value of at least about 6.4 as determined by hydroxyl number and m has a value such that the oxyethylene portion constitutes about 10 to weight percent of the molecule. Most of the surface active agents are more particularly described in US. Patent No. 2,677,700.

Other conjugated polyoxyalkylene surface active agents which are most advantageously used in the compositions of the invention correspond to the formula:

3 6 )n( 2 4 )m ]x wherein Y is the residue of an organic compound having from about two to six carbon atoms and containing as reactive hydrogen atoms in which 1: has a value of at least about two, n has a value such that the molecular weight of the polyoxypropylene hydrophobic base is at least about 900 and m has a value such that the oxyethylene content of the molecule is from about 10 to 90 weight percent. Compounds falling within the scope of the definition for Y include, for example, propylene glycol, glycerine, pentaerythritol, trimethylolpropane, ethylenediamine, triethylenetetramine, triisopropanolamine and butylamine. Where Y is ethylenediamine, the compounds may be represented by the formula:

ntcimomcimo) wimomcintomi NCHr-CHr-N 3 )1( l )s (C$ I )I(CI IO)H wherein at and y are integers. As already noted, the oxypropylene chains optionally, but advantageously, contain small amounts of ethylene oxide and the oxyethylene chains also optionally, but advantageously, contain small amounts of alkylene oxides having an oxygen/carbon atom ratio of not more than about 0.33 such as propylene oxide and butylene oxide. Most of these compounds are more particularly described in US. Patent Nos. 2,674,619 and 2,979,528.

Other suitable polyoxyethylene nonionic surface active agents are the ethylene oxide adducts of higher aliphatic alcohols having from about 8 to 22 carbon atoms in the aliphatic portion, and about 3 to 30 ethenoxy units in the oxyethylene portion. Typical products are blends of linear fatty alcohols containing an even number of carbon atoms condensed with about three to nineteen moles of ethylene oxide.

Other suitable nonionic surface active agents are the propylene oxide adducts of condensates of ethylene oxide and higher aliphatic alcohols having from about 8 to 22 carbon atoms in the aliphatic portion. Various ratios of ethylene oxide and propylene oxide may be used.

Other suitable nonionic surfactants are the products prepared by condensing a mixture of ethylene oxide and propylene oxide with aliphatic alcohols having from about 8 to 22 carbon atoms in the aliphatic portion of the alcohol. Various ratios of oxides may be employed.

Other suitable surface active agents are the polyoxyalkylene surface active agents having heteric polyoxyethylene solubilizing chains. These polyoxyalli'ylene compounds conform to the following generic formula:

wherein Y is the nucleus of an organic reactive hydrogen compound containing 1: reactive hydrogen atoms and having up to six, inclusive, carbon atoms, x is an integer, P is a hydrophobic polyoxyalkylene chain having an oxygen/carbon atom ratio of not more than 0.40, the molecular weight of P and the value of at being such that the molecule, excluding E, has a molecular weight of at least about 400 to 900 and up to about 25,000, and E is a hydrophilic heteric polyoxyalkylene chain which (1) contains oxyethylene groups and at least five percent by weight of higher molecular weight oxyalkylene groups having at least three carbon atoms in their structure, and (2) has an average oxygen/carbon atom ratio of greater than 0.40, E being present in the composition to the extent that it constitutes from 5 to 90 weight percent of the total composition. These compositions are more particularly described in US. Patent No. 3,101,374. Mixtures of these compositions and fatty acid phosphates may also be used.

The surfactants are employed in the form of an aqueous solution, generally a 50 percent aqueous solution. The amount of water employed is critical. The amount of water should only be suflicient to hydrate the phosphate ingredient. Any excess water will detrimentally affect the resulting product since water reacts with the active chlorine-containing compound to release the chlorine, which in turn reacts with the surfactant. This causes degradation of the product and loss of available chlorine. Based on 100 parts of detergent composition, from one to ten parts of surfactant and from one to fifteen parts of water may be employed provided, however, that the sum total of water and surfactant is at least ten parts. Preferably, five parts of water and five parts of surfactant are employed.

As stated before, the detergent compositions of this invention are prepared by a particular sequence of steps. In the first step, an aqueous solution of surfactant is added to a phosphate ingredient. These surfactants may be added in any manner; for example, by pouring or spraying. By adding the surfactant and water to the phosphate ingredient alone, hydration of the phosphate occurs in the presence of the surfactant which is simultaneously absorbed by the phosphate ingredient. This protects the surfactant from action by the metasilicate and chlorinated compound which are subsequently added. Simultaneous addition of the metasilicate and surfactant, or addition of the metasilicate to a phosphate ingredient which has not absorbed the surfactant, results in discoloration, degradation and agglomeration of the product.

The second step of the process of this invention involves the addition of the hydrated metasilicate to the hydrated product of the first step. The addition occurs with constant mixing. For the reasons discussed above, it is essential the metasilicate be added after the phosphate ingredient is hydrated and has absorbed the surfactant.

The third step of the process of this invention is a size reduction step. The mixture from the first or second step is reduced to any desired size by any conventional means such as crushing, grinding and preferably screening. It is preferred to reduce the size of the mixture from the second step and, therefore, for convenience sake, this step is referred to as the third step. It is, of course, obvious that if size reduction occurs on the mixture from the first step, then the size reduction step is the second step of the process. Generally, when the mixture is screened, a S-mesh to 25-mesh screen will be used since this is the size most appropriate for automatic machine operations.

The fourth step of the process of this invention is the addition of the active chlorine-containing compound to the screened mixture. In some instances, this compound may be added along with the metasilicate. However, this is only so when no moisture is present in the hydrated product from Step 1. Since it is diflicult to assure that no moisture is present, it is advisable to add the chlorine compound after the metasilicate has been added since the metasilicate will absorb any moisture present.

The process of this invention offers many advantages over known processes. To mention a few, the process of this invention:

(1) provides for the preparation of chlorine-stable detergent compositions containing nonionic surfactants,

(2) avoids any temperature control problems, and

(3) obviates the need for an aging period.

The following examples illustrate the invention. All parts are by weight unless otherwise stated.

Example I-III Several detergent compositions were prepared in the manner set forth below. The particular ingredients employed, the amounts thereof and the chlorine stability of the resulting products are presented in Table l. Chlorine stability is determined by analyzing the available chlorine content immediately after preparing the composition and reanalyzing the chlorine content as days elapse.

The compositions were prepared by first dissolving a surfactant in water to form a 50 percent solution thereof. The surfactant solution was then sprayed onto mixed tetrasodium pyrophosphate or a mixture of tetrasodium pyrophosphate and other inorganic salts. As the phosphate ingredient became hydrated, all the surfactant was simultaneously absorbed, forming agglomerates of various sizes.

Sodium metasilicate pentahydrate was then added to the agglomerates with continuous mixing. The mixed products were then screened through a ten-mesh screen and dry, free-flowing granular products were obtained. To these products, an active chlorine-containing compound was admixed with constant tumbling. Dry, free-flowing granular products were obtained which retained their dry, free-flowing granular form for over seven months.

1 Commercial product.

I Product prepared by condensing tour moles of propylene oxide with the condensation product of one mole of a mixture of Gig-Ci. alcohols with eight moles of ethylene oxide.

I Product prepared by condensing three moles of propylene oxide withthe condensation product of one mole of a mixture of O e-C alcohols with six moles of ethylene oxide.

4 Plnronic L6i-Product prepared by condensing ethyleneoxide with polypropylene glycol. Total molecular weight is approximately 2,000, of which about 10 percent is ethylene oxide.

7 Examples lV-X Several detergent compositions were prepared following the procedure set forth above. The ingredients employed were:

Parts Parts of tetrasodium pyrophosphate 35 Sodium carbonate 20 Surfactant, 50 percent aqueous solution 20 Water, deionized Sodium metasilicate pentahydrate Chlorinated trisodium phosphate 10 The active chlorine-containing compounds employed were:

Ex. Xl--l,3-dichloro-5,5-dimethylhydantoin EX. XIItrichlorocyanun'c acid Ex. Xl'II-sodiurn dichlorocyanurate Ex. XIV-potassium dichlorocyanurate.

All of the detergent compositions of the above Examples XI-XIV were excellent dishwashing compositions 10 with stable chlorine contents.

Examples XV-XXI Using the procedure discussed above, various detergent compositions were prepared using a variety of inorganic builders. In all instances, the other ingredients employed were:

Parts Sodium metasilicate pentahydrate 10 Chlorinated trisodium phosphate l0 Surfactant (Pluronic L61), 50 percent aqueous solution 20 Water, deionized 5 The inorganic builders used and the results of the chlorine stability test appear in Table 2.

TABLE 2 P Ingredients ans by weight XV XVI XVII XVIII XIX XX XXI ge gasodiurg prrophosphate 55 o urn car onate 20 37. 5 5 Sodium tripolyphosphate 17. 5 6 5 53 20 20 Sodium sulfate. 35 Sodium borate. 535 Percent of starting available chlorine content at accelerated degradation 0.):

After two days 75 75 18 0 1O After six days 57 5s a o o o "6 Percent of starting available chlorine content at room temperature alter 130 days 88 89.1 47. 5 46. 6 45. 4

Compound became discolored and, therefore, was not further tested.

densate of polypropylene glycol containing about ten percent ethylene oxide;

Ex. VII-a 5350 molecular weight ethylene oxide condensate of polypropylene glycol containing about twenty percent ethylene oxide;

Ex. VIII-a 2450 molecular weight ethylene oxide condensate of polypropylene glycol containing about 25 percent ethylene oxide;

Ex. IX-a mixture containing three percent monostearyl acid phosphate and 97 percent of the compound employed in Example IV, and

Ex. X-a condensation product of a mixture of ethylene oxide and propylene oxide with a mixture of C1TC13 alcohols.

All of the detergent compositions of the above examples formulated with no difliculty. They were excellent dishwashing detergents and proved to be stable with respect to the available chlorine content.

Example XI-XIV Following the procedure set forth under Examples IIII, several detergent compositions were prepared using various active chlorine-containing compounds.

The ingredients employed were:

Parts Tetrasodium pyrophosphate 35 Sodium carbonate 20 Sodium metasilicate pentahydrate 10 Pluronie L61, 50 percent aqueous solution 20 Water, deionized 5 Active chlorine-containing compound 10 45 From the data presented in Table 2, it is apparent that tetrasodium pyrophosphate is essential to the preparatron of the chlorine-stable detergent compositions of this invention.

50 Example XXII A detergent dishwashing composition was prepared from:

The composition was prepared following the procedure described in Example I with the exception that the hydrated phosphate product from Step 1 was screened prior to the addition of the metasilicate. A dry, free-flowing granular product was obtained. After 120 days, 89 percent of the starting available chlorine content remained.

Example XXIII In order to demonstrate the necessity of preparing the detergent compositions according to the process of this 7 invention, several compositions were prepared varying 9 the sequence of preparation. The compositions were prepared with:

(a) This composition was prepared by mixing the tetrasodium pyrophosphate, sodium carbonate, sodium metasilicate and chlorinated trisodium phosphate and then adding the surfactant and water. Slight discoloration occurred. Within eight days at accelerated degradation (50 C.) analysis showed no detectable amount of available chlorine remaining. After two months at room temperature, only 58 percent of the starting available chlorine content remained.

(b) This composition was prepared by mixing tetrasodium pyrophosphate, sodium carbonate and sodium metasilicate pentahydrate and then adding the surfactant and water. After screening, chlorinated trisodium phosphate was added. Although the product was free-flowing and granular, the available chlorine content decreased rapidly, dropping to 32.7 percent of that of the start within six days at 50 C. temperature storage.

(c) This composition was prepared by adding the metasilicate and surfactant simultaneously to the mixture of tetrasodium pyrophosphate and sodium carbonate and then adding the chlorinated trisodium phosphate. (This procedure is similar to that of U.S. 2,895,916, the only difference being that metasilicate was used in lieu of sodium silicate.) The composition was difficult to formulate since gelling occurred. The composition was somewhat sticky and tended to cake at accelerated degradation (50 C.). Extremely rapid degradation was observed. There was a slight discoloration of the product within one day. In five days at 50 C. temperature storage, analysis showed no detectable amount of available chlorine remaining.

(d) This composition was prepared in the manner set forth in Example 4 of U.S. 2,895,916. Dry sodium silicate was used. A dry powder was obtained only after the product was crushed with an agate mortar and pestle prior to screening. After six days at accelerated degradation (50 C.), analysis showed no available chlorine content. Thus, for all practical purposes, this composition was chlorine-free.

Example XXIV An eggwashing composition was prepared in the manner set forth above. The composition comprised:

Surfactant used in Example 11, 50 percent aqueous solution 10 Sodium metasilicate pentahydrate 10 Chlorinated trisodium phosphate 22 After 120 days, 94 percent of the starting available chlorine content of the composition remained. Use of the composition in Kuhl and Seymour eggwashing machines demonstrated superior results over several commercially available products.

What is claimed is:

1. A process for the preparation of a chlorine-stable detergent composition consisting essentially of, based on 100 parts of said composition, from 35 to 80 parts of an alkaline condensed phosphate, from 5 to 15 parts of a hydrated metasilicate, from 5 to 25 parts of an active chlorine-containing compound, from 1 to parts of a nonionic surfactant, and from 1 to parts of water,

or s 10 the sum total of said surfactant and water being at least 10 parts which comprises:

(a) adding an aqueous solution of a nonionic surfactant to an alkaline condensed phosphate selected from the group consisting of tetrasodium pyrophosphate and mixtures of tetrasodium pyrophosphate and other inorganic salts other than sodium meta-silicate, said mixtures containing at least 50 percent by weight tetrasodium pyrophosphate, whereby hydration of the condensed phosphate and simultaneous absorption of the surfactant occurs;

(d) adding an active chlorine-containing compound selected from the group consisting of chlorinated trisodium phosphate, chlorinated cyanuric acids and alkali metal salts thereof, and 1,3-dichloro-5,5-dimethylhydantoin to the mixture from (c) whereby a dry, free-flowing, granular product is obtained.

2. The process of claim 1 wherein the surfactant is added in the form of a 50 percent aqueous solution.

3. The process of claim 1 wherein the surfactant is a compound of the formula Y[(C I-I O),,(C H O) ,H] wherein Y is the residue of an organic compound having from about two to six carbon atoms and containing x reactive hydrogen atoms in which .1: has a value of at least about two, n has a value such that the molecular weight of the polyoxypropylene hydrophobic base is at least about 900 and m has a value such that the oxyethylene content of the molecule is from about 10 to weight percent.

4. The process of claim 1 wherein the alkaline condensed phosphate is tetrasodium pyrophosphate.

5. The process of claim 1 wherein the alkaline condensed phosphate is a mixture of tetrasodium pyrophosphate and sodium carbonate.

6. The process of claim 1 wherein the active chlorinecontaining compound is chlorinated trisodium phosphate.

7. The process of claim 1 wherein the hydrated metasilicate is sodium metasilicate pentahydrate.

8. A process for the preparation of a chlorine-stable detergent composition consisting essentially of, based on parts of said composition, from 35 to 80 parts of an alkaline condensed phosphate, from 5 to 15 parts of a hydrated metasilicate, from 5 to 25 parts of an active chlorine-containing compound, from 1 to 10 parts of a nonionic surfactant, and from 1 to 15 parts of water, the sum total of said surfactant and water being at least 10 parts which comprises:

(a) adding an aqueous solution of a nonionic surfactant to an alkaline condensed phosphate selected from the group consisting of tetrasodium pyrophosphate and mixtures of tetrasodium pyrophosphate and other inorganic salts other than sodium meta-silicate, said mixtures containing at least 50 percent by weight tetrasodium pyrophopshate, whereby hydration of the condensed phosphate and simultaneous absorption of the surfactant occurs;

(b) reducing the size of the mixture resulting from (a) to a desired particle size;

(c) adding, with mixing, a hydrated sodium metasilicate to the mixture from (b), and

(d) adding an active chlorine-containing compound selected from the group consisting of chlorinated trisodium phosphate, chlorinated cyanurie acids and alkali metal salts thereof, and 1,3-dichloro-5,5-dimethylhydantoin to the mixture from (c) whereby a dry, free-flowing granular product is obtained.

9. A chlorincastable detergent composition consisting essentially of, based on 100 parts of said composition, from 35 to 80 parts of an alkaline condensed phosphate, from 5 to 15 parts of a hydrated metasilicate, from 5 to 25 parts of an active chlorine-containing compound, from 1 to 10 parts of a nonionic surfactant, and from 1 to 15 parts of water, the sum total of said surfactant and water being at least parts prepared by:

(d) adding an active chlorine-containing compound selected from the group consisting of chlorinated trisodium phosphate, chlorinated cyanuric acids and alkali metal salts thereof, and 1,3-dichloro-5,5-dimethylhydantoin to the screened mixture whereby a dry, free-flowing granular product is obtained.

10. The composition of claim 9 when the alkaline condensed phosphate is tetrasodium pyrophosphate.

11. The composition of claim 9 when the alkaline condensed phosphate is a mixture of tetrasodium pyrophosphate and sodium carbonate.

12. The composition of claim 9 when the surfactant is a compound of the formula Y[C H,,O),,(C;;H O) H] wherein Y is the residue of an organic compound having from about two to six carbon atoms and containing x reactive hydrogen atoms in which at has a value of at least about two, n has a value such that the molecular weight of the polyoxypropylene hydrophobic base is at least about 900 and m has a value such that the oxyethylene content of the molecule is from about 10 to weight percent.

13. The composition of claim 9 when the active chlotilting-containing compound is chlorinated trisodium phosp te.

14. The composition of claim 9 when the hydrated metasilicate is sodium metasilicate pentahydrate.

References Cited UNITED STATES PATENTS 2,895,916 7/1959 Milenkevich et a1. 252-99 3,154,497 10/1964 Mankowich 252- 3,247,118 4/1966 Matthaei 252-99 3,306,858 2/1967 Oberle 252-99 LEON n. ROSDOL, Primary Examiner. 2911s, M. WEINBLATT, Assistant Examiner.

Claims

1. A PROCESS FOR THE PREPARATION OF A CHLORINE-STABLE DETERGENT COMPOSITION CONSISTING ESSENTIALLY OF, BASED ON 100 PARTS OF SAID COMPOSITION, FROM 35 TO 80 PARTS OF AN ALKALINE CONDENSED PHOSPHATE, FROM 5 TO U5 PARTS OF A HYDRATED METASILICATE, FROM 5 TO 25 PARTS OF AN ACTIVE CHLORINE-CONTAINING COMPOUND, FROM 1 TO 10 PARTS OF A NONIONIC SURFACTANT, AND FROM 1 TO 15 PARTS OF WATER, THE SUM TOTAL OF SAID SURFACTNT AND WTER BEING AT LEAST 10 PARTS WHICH COMPRISES: (A) ADDING AN AQUEOUS SOLUTION OF A NONIONIC SURFACTANT TO AN ALKALINE CONDENSED PHOSPHATE SELECTED FROM THE GROUP CONSISTING OF TETRASODIUM PYROPHOSPHATE AND MIXTURES OF TETRASODIUM PYROPHOSPHATE AND OTHER INORGANIC SALTS OTHER THAN SODIUM META-SILICATE, SAID MIXTURES CONTAINING AT LEAST 50 PERCENT BY WEIGHT TETRASODIUM PYROPHOSPHATE, WHEREBY HYDRATION OF THE CONDENSED PHOSPHATE AND SIMULTANEOUS BSORPTION OF THE SURFACTANT OCCURS; (B) ADDING A HYDRATED SODIUM METASILICATE TO THE HYDRATED CONDENSED PHOSPHATE WITH MIXING; (C) REDUCING THE SIZE OF THE MIXTURE RESULTING FROM (B) TO A DESIRED PARTICLE SIZE, AND (D) ADDING AN ACTIVE CHLORINE-CONTAINING COMPOUND SELECTED FROM THE GROUP CONSISTING OF CHLORINATED TRISODIUM PHOSPHATE, CHLORINATED CYANURIC ACIDS, AND ALKALI METAL SALTS THEREOF, AND 1,3-DICHLORO-5,5-DIMETHYLHYDANTION TO THE MIXTURE FROM (C) WHEREBY A DRY, FREE-FLOWING GRANULAR PRODUCT IS OBTAINED.