US2455050A - Nondusting detergent compositions - Google Patents

Description

Patented Nov. 30,1948

NONDUSTING DETERGENT COMPOSITIONS Sidney Eisenberger, New York, and Samuel Machlis, New Rochelle, N. Y., asslgnors to 0. D; Chemical Corporation, New York, N. Y., a corporation of New York l lo Drawing.

This invention relates to new detergent compositions and more particularly to a non-dusting detergent composition resist-ant to lumping.

The new detergent compositions contain tetraalkali pyrophosphate and other alkaline salts including sodium carbonate, together with from to 25% of a complex mixture of alkyl naphthalene sulfonates in which the alkyl groups'resuit from condensation with naphthalene of a petroleum fraction made up of hydrocarbons containing from 3 to 6 carbon atoms and a small fraction of a percent of diethylene glycol stearate.

An intimate admixture of the alkaline salts and the complex mixture of alkyl naphthalene sulfonates in a finely dividedstate are treated with a small percentage of an aqueous suspension of diglycol stearate which is thoroughly admixed with and distributed throughout the mixture. And, after thorough admixture, the composition ls allowed to stand and further reaction takes place particularly between the small percentage of added water and hydratable alkaline salts.

A small amount of bentonite is also advantageously included in the composition.

The complex mixture of alkyl naphthalene sul- Application January 11, 1947, Serial No. 721,666

6 Claims. (Cl. 252-138) In general, the new detergent compositions contain from 10 to 50% of the complex detergent, from 10 to 50% of tetrasodium pyrophosphatc, and the balance other alkali salts, particularly sodium carbonate and bicarbonate, in proportions to regulate the pH of the resulting detergent composition when added to water for use as a detergent solution. A small amount of bentonite is in some cases advantageously added,

particularly as a conditioning agent for preventing lumping or reducing lumping in the, composition, the amount of bentonite when used ranging from around 5 to. 10%.

Such detergenhppmppsitions, except for the treatment thereof and compounding thereof oi the diethylene glycol stearate, are described in our prior application Serial No. 619,258. v

Such compositions without the treatment with the diethylene glycol stearate readily lump in damp weather when exposed to the air into a gummy mass; and in a powdery form the mixture tends to dust freely and cause sneezing. But by spraying the detergent mixture with a small percent of an aqueous suspension of diethylene glycol stearate, in amount corresponding to a small fraction of one percent of the detergent ionates, hereinafter referredto for convenience and simplicity as synthetic detergent, is made by condensing with naphthalene a petroleum fraction composed of hydrocarbons containing from 3 to 6 carbon atoms, sulfonating the resulting product and neutralizing with, e. g., sodium hydroxide. The complexity of the resulting mixture of alkyl naphthalene sulfonates makes it difficult to assign a formula, but it may be assumed that the complex product thus obtained is a complex mixture of various alkali alkyl naphthalene sulfonates in which there is attached to each naphthalene, in addition to the sulfonate group, one or more primary, secondary or tertiary alkyl groups containing from 3 to 6 carbon atoms. A product of this nature which we have found particularly advantageous in the new compositions is a product sold under the name Sellogen ASD.

This complex mixture of alkyl naphthalene sulfonates by itself showed little if any detergency in soft or hard water, as measured by launderometer tests on standard soiled wool according to the methods of the American Society for Testing Materials; but when compounded with tetrasodium pyrophosphate and other alkaline salts mixture, and by thoroughly stirring or agitating after it is so sprayed and then allowing it to stand, the detergent composition is converted into a composition which is resistant to lumping and which is non-dusting.

-The detergent compositions which are thus treated with the diethylene glycol stearate may thus contain from 10 to 50% of the synthetic detergent (the complex alkyl naphthalene sulfonates), from 10 to 50% of tetrasodium pyro- .phosphate and the remainder soda ash and sodium bicarbonate, with the proportions ad-,

in suitable proportions, it enables particularly valuable detergent compounds to be produced.

Compositions are thus advantageously made containing 10 to 20% of the synthetic detergent, from 10 to of tetrasodium pyrophosphate, from 15 to of sodium bicarbonate, from 15 to 40% of soda ash (sodium carbonate) and 0 to 5% of bentonite.

A typical and advantageous formula is one containing about 15% of the synthetic detergent, about 30% of tetrasodium pyrophosphatc, about 25% of soda ash, about 25% of sodium bicarbonate and about 5% of bentonite.

In converting such a composition into a nondusting composition resistant to caking, the

composition is sprayed with an aqueous suspcnslon oi diethylene glycol stearate, containing around 6% of diethylene glycol stearate emulsifled or dispersed at a temperature of around 180 to 200 F. in an amount of water representing only a small percentage, around 1% to 3% by weight, of the detergent composition; and the a composition is thoroughly admixed and then permitted to stand, 2. g. 24 hours or more. The composition can thus be sprayed with about two pounds of a 6% dispersion of diethylene glycol stearate (self-emulsifying) in water per 100 pounds of dry mixture and then thoroughly ad mixed in a powder mixing machine, such as ribbon dry powder mixer, to effect thorough admixture and distribution of the diethylene glycol stearate throughout the powdery composition. The resulting composition is then discharged from the mixer into drums or trays or trucks and allowed to stand for from 1 to 3 days at ordinary temperature. Some agglomeration takes place, the product being partly agglomerated and partly set into lumps but being readily broken down, by grinding into a product which is free-flowing, which has little or no hydroscopic properties and which is free from dust.

The diethylene glycol stearate used is advantageously in the form of a self-emulsifying product, such as one which contains a small amount of soap or other emulsifying agent which makes it self-emulsifying in water. A commercial selfemulsifying diethylene glycol 'stearate is sold under the trade name Diethylene Glycol Stearate S.

The water which is used in the aqueous dispersion or emulsion of the diethylene glycol stearate appears to react with or combine with and to be helclibyth'e constituents of the compositions probably in part as water of hydration of sodium carbonate (soda ash) and possibly in part by the bentom'te when bentonite is used. The efiect of the diglycol stearate suspension when sprayed on the dry powdery composition and thoroughly admixed therewith is probably in part an agglomerating action of fine particles and in part a coating of the particles with the diethylene glycol stearate. The amount of aqueous suspension can be varied and somewhat less water is advantageously used when bentonite is not present in the composition than when benton-ite is present. The presence of bentonite also appears advantageous in reducing the agglomeration and caking of the product on standing and setting.

After the dry powder composition has been sprayed with the aqueous suspension of diethylene glycol stearate and thoroughly admixed therewith and allowed to stand, the product is broken up, where it is agglomerated and is readily reduced by grinding to a product which is freeflowing, granular in character, non-hygroscopic and non-dusting.

Detergent compositions which, in an untreated state without spraying with the diethylene glycol stearate suspension,- will readily lump in dam weather into a gummy mass: and which in a powdery form will dust freely and cause considerable sneezing, are converted by the treatment into a granular p oduct which .is non-dusting and which is resistant to lumping in damp weather.

The soda ash (sodium carbonate) appears to play an important part in the composition in combining with the added water, preventing the gumming up and caking of the compositions on spraying which would take place if the sodium carbonate were not present The new detergent compositions oi. the pres- 4 ent invention have the advantages of the detergent compositions of said prior application Serial No. 619,258 and in addition have the added advantages of being non-dusting and resistant to caking and of bein in a more or less granular condition.

Variations in proportions can be made in the ingredients used and some of the alkali salts can be replaced to a greater or lesser extent by other alkali salts. In general an amount of tetrasodium pyrophosphate equal to or advantageously considerably in excess of the amount of synthetic detergentis used. Thus, in some cases up to 10% of borax can be substituted for part of the mixture of sodium carbonate and bicarbonate.

The new detergent compositions are valuable compositions, giving satisfactory or superior performance in a wide variety of cleaning problems from laundering fine fabrics to washing floors and under a wide range of temperature and water hardness. They are valuable household detergents and also useful for industrial purposes, such as maintenance cleansing, car washing, dish washing, commercial laundering, etc.

We claim:

1. The method of rendering a detergent consisting essentially of from about 10% to 50% of a complex mixture of alkyl naphthalene sulfonates in which the alkyl groups contain from 3 to 6 carbon atoms, about 10% to 50% of tetrasodium pyrophosphate and from about 15% to 40% of at least one alkali-metal carbonate from the class consisting of soda ash and sodium bicarbonate non-dusting and free-flowing which comprises spraying the same with a dilute aqueous dispersion of diethylene glycol stearate, thoroughly admixing the sprayed mixture, permitting it to stand for a substantial period of time, and grinding the resulting composition to obtain a non-dusting,

free-flowing, granular product.

2. The method of rendering a detergent consisting essentially of from about 10% to 50% of a complex mixture of alkyl naphthalene sulfonates in which the alkyl groups contain from 3 to 6 carbon atoms, about 10% to 50% of tetrasodium pyrophosphate and from about 15% to 40% of at least one alkali-metal carbonate from the class consisting of soda ash and sodium bicarbonate non-dusting and free-flowing which comprises spraying the same with a small percentage of a dispersion of diethylene glycol stearate amounting to'a small fraction of 1% of the mixture.

3. The method of rendering a detergent consisting essentially of from about 10% to 20% of a complex mixture of alkyl naphthalene sulfonates in which the alkyl groups contain from 3 to 6 carbon atoms, about 10% to 30% of tetrasodium pyrophosphate, about 15% to 40% of soda ash, about 15% to 40% of sodium bicarbonate and from 0% to 5% of bentonite non-dusting and free-flowing which comprises spraying the same with a dilute aqueous dispersion of diethylene glycol stearate, thoroughly admixing the sprayed mixture, permitting it to stand for a substantial period of time, and grinding the resulting composition to obtain a non-dusting, free-flowing, granular product.

4. A non-dusting detergent composition consisting essentially of from about 10% to 50% of a complex mixture of alkyl naphthalene sulfonates in which the alkyl groups contain from 3 to 6 carbon atoms, about 10% to 50% of tetrasodium pyrophosphate and from about 15% to 40% of at least one alkali-metal carbonate from the class consisting of soda ash and sodium bicarbonate,

mesgoto together with asmall fraction of 1% of diethylehe about 25% oi soda, ash, bout 25% of um bi glycol stem'ate intimately distributed therein. carbonate and about 5% of bentonite; together 5. A non-dusting detergent composition conwith a small fraction of 1% of diethylene glycol sisting essentially of about to of a comstearete intimately distributed therein. plex mixture of alkyl naphthalene sulfonates in 5 which the alkvl groups contain from 3 to 6 carbon atoms, about 10% to of tetrasodium pyrophosphate, about 15% to 40% of soda ash, about 7 15% to 40% of sodium bicarbonate and from 0% REFERENCES CH'EED to 5% of bentonite, together with a, small irac- 10 on of 1% of methylene glycul steam The following references are of record in the timately distributed therein. this 6. A non-dusting detergent composition cori- UNITED TA ES PATENTS sisting essentially oi about 15% of & complex Numb N mixture of alkyl naphthalene sulformtesin which 15 3 g zff gfi the alkyl EIOUPS contain from 3 $0 6 carbon 2 3 4 0 Edwards 19%4 atoms, about of tetmsodium pyrophosphate,