US2982738A

US2982738A - Cleansing composition and method of manufacture thereof

Info

Publication number: US2982738A
Application number: US597590A
Authority: US
Inventors: Schmolka Irving Rudolph
Original assignee: Colgate Palmolive Co
Current assignee: Colgate Palmolive Co
Priority date: 1956-07-13
Filing date: 1956-07-13
Publication date: 1961-05-02
Anticipated expiration: 1978-05-02

Description

'move' withthe detergent alone. other soaps have been used to convert hydrocarbon sol- 'vents jinto solid forms. Gasoline and other hydrocar- -bons have been jellied by the addition of certain sul- CLEANSING COMPOSITION METI-IOD'OFv MANUFACTURE THEREOF Irving Rudolph Schmolka, Astoria, N.Y., assignor to Colgate-Palmolive Company; New York, N.Y.,' a corporatiou of Delaware No Drawing. Filed July 13, 1 956, Ser. No. 597,590

' 6 Claims. I or. 252-153 This invention relates to gel cleansing compositions comprising alkanes with amides of sarcosine. More particularly the alkanes are those aliphatic compounds having a boiling range between 350 F. and 500 F. and the sarcosine amides are those of higher fatty acids. The

invention also includes methods of making the cleansing compositions.

It has been known to make soaps and synthetic de- "tergent compositions containing solvents which improve {the cleaning power of such products by exerting their loosening and dissolving action on soils difiicult to re- Alurninum soap and fonated and sulfated organic compounds. So-called waterless hand cleaners have been marketed in paste or I gelj forms; these normally comprise a major amount of water with a detergent and sometimes a solvent is ineluded.

None of the above products has been a truly satisfactory cleansing composition of excellent cleansing'action, mildness to the skin, satisfactory consistency and stability,

reasonable price and simplicity of manufacture. The 'present invention is a creamy or jellified product hereafter referred to as a gel, which possesses all these neces- "sary'properties and is especially suitable for removing paint, grease, oily grime or other highly lipophilic material from the skin. .In accordance with the present invention a cleansing composition in gel form comprises a major proportion of an alkane having a boiling range between 350 F. and 500 F. and a minor proportion of a water soluble salt of a higher fatty amide of sarcosine, the proportion of said sarcosine amide being sufiicient to form a gel with the alkane. Such products are especially useful as hand icleaners for mechanicsand painters.

',The,alka'ne need not be a pure compound but should preferably be odorless or .deodorized, at least free of fcobjectionable malodorous components. Usually the alkane is a mixture of parafiins similar to those found in fractions of kerosene.

Such' mixtures are normally identified by their boiling ranges and aromatic content (which may bereported in terms of physical test results) rather than .by chemical formulas.

The. boiling range of the present alkanes'extendsfrom 350 F. to 500 F. at atmospheric pressure and: is preferably from 400 F. to 500 F. Of course, as with most natural materials, a

slight residue (about 1 to 4%) boiling well above the upper temperature limit may be present provided that it does not prevent gelation. p

Alkanes boiling below 350 F. do not form gels with sarcosine amides as satisfactory as those gels containing alkanes of the higherv boiling ranges given above. The

alkanes boiling below 350 F. also exert a relatively StAtCiS Paten 2,982,738 Patented May 2, 19 61 ICC strong solvent action at room temperature and tend to cause irritation of the skin. These materials are unsuitable as skin cleansers or for application to soiled surfaces by hand. Alkanes boiling above 500 F. are not sufficiently good solvents for use as such in cleansers applied at room or body temperatures.- Alkanes boiling 'in the narrow preferred range of 400 F, to 460 F. are

even milder to the skin than those of the broader useful spectrum given above and are of excellent solvent power commensurate with the function of thecleanser. The elimination of the lower boiling compounds allows the production offirmer gels. In those cases where the gels made with broader spectrum solvents are too soft for commercial acceptance in certain applications itpis important that the solvent alkane of narrow boiling range be employed to correct this deficiency.

Kerosene fractions sometimes contain aromatic and olefinic compounds. Such compoundsare stronger solvents and also tend to' soften sarcosine amide gels; they consequently should'not be present in the alkanes for best gel formation and performance. The amount of such compounds in the cleansing gel must be kept low enough so as 'not {to prevent adequate gelation. Usually, less than 5%- aromatics' and 5 olefins willbe present in the kerosene fraction used in :producing the. gels of this invention, but somewhat higher percentages are acceptable provided thata satisfactory gel can be made. T In addition to the small amount ofaromatic and olefinic compounds, the present alkanes often include cyclic compounds, known in the petroleum art as naphthenes, together with the aliphatic alkanes of straight and branched chain configuration. Of these latter compounds it is preferred to employ the normal. alkanes, or alkane mixtures containing a predominance or major amount of normal alkanes or at least a substantial: portion thereof, e.g. 30%. However, branched chain 'alkanes may point of about 200 F., indicating low content of aromaticcompounds, is an excellent component of the present gels.- Such an' alkane consists mostly "of straight chain parafiins with about 2% aromatic impurities.

The higher fatty amides of sarcosine maybe obtained by condensing a salt of sarcosine and a higher 'fatty' acid halide in an alkaline medium according to' well-known processes.

Of the amides described it is preferred to employ those of saturated fatty acids of 10-'-18 carbon atoms, especially of 12-16 carbon atoms, viz., lauric, acids, or mixtures thereof. V n p The amide compounds described should be in the form of Water-soluble salts. Among the salts that may be used are those having suitable mon ovalent or polyvalent cationic radicals, e.g. sodium, alkylolamine, provided that the salt is compatible with the particular solventmedium and forms a satisfactory gel with it. Of the amide salts tested sodium gives the firmest gels and .is most satisfactory. 1

myristic and palmitic and dispensing from a jar ortube.

. the present composition to alter its properties.

firmness, as a rule more amide of shorter acyl chain .length will be required. Usually the alkane solvent should constitute a majorpart of'the cleansing compov,

aaaearas sition. When employing-sarcosine amides of fatty acids of to 18 carbon atoms, the use of more than about 30% amide, the balance being alkane solvent, will result in a hard gelatinous product unsuitable for packaging in Such a product may find main bar or cake formor as a specialty item.

Most solid or gel cleansers containing solvents, es-

pecially skin or hand cleansers, are most conveniently and acceptably packaged intubes or jars, from which the user may extrude or easily scrape a desired quantity. The invented gels having 2,-30% sarcosine amide content and marketable in tubes or jars are characterized as sof gels.

If the concentration of sarcosine amide of the described type is about between 2 and the resulting gel cleanser is easilyextruded from a conventional collapsible dispensing tube as a strip of creamy consistency, much like dental cream in appearance.

For packaging in collapsible tubes an alkane solvent gel of the type described desirably contains 4 to 15% preferably 6 to 10% of the sodium salt of lauric acid amide of sarcosine or 3 to 13%, preferably 5 to 9% of the correspondingpalmitic. acid amide salt. The myristic compound can be employed in an intermediate amount.

If more than about 15% sarcosine amide but less than about is formulated in alkane solvent the gel resulting will be too firm to permit dispensing from a tube but i can be poured into jars when warm and can be easily scraped therefrom with slight fingerpressure by the user. Although 15 sarcosine amide content represents a nor mal division between tube and jar compositionsit will be realized that this borderline is dependent to a degree on the composition of the gel under consideration.

As can be readily understood it will oftenbe an important consideration that the finished cleansing composition be of proper consistency and firmness for the desired end use of the product. Water and water soluble inorganic salts present in the gel, tend to reduce the stability of the final product during storage because they are not sufficiently compatible with the oily materials and tend not to remain in homogeneous mixture with them. Water also exerts a thinning action on the gel and, if present in suflicient amount, prevents gelation. Water soluble inorganic salt tends to grain the gel, decrease its elasticity and make it an opaque dead white. To prevent these Other detergents may be added to the present composition when it is desired to supplement or alter the cleansing action of the sarcosine amide salt. Thus, non-gelling or poorly gel-ling synthetic detergents such as sodium lauryl sulfate, non-ionics, e.g., block copolymers of polyoxyethylene with water-insoluble polyoxypropylene (Pluronics), may be incorporated in the described gels provided that the gels made are of satisfactory firmness. Such compounds, being organic-based do not exhibit the unstabilizing influence of water soluble inorganic salts. They may constitute from 0.1% to as much as 90 of the non-solvent part of the gels; in the latter cases the sarcosine derivatives maybe considered as an agent for converting a non-gelling synthetic detergent into gel form.

To make the disclosed gels it is necessary only to mix the alkane and sarcosine amide thoroughly at an elevated temperature so as to promote gel formation. To do this most easily it is preferred to mix the alkane and amide and heat to a temperature at which the amide is soluble in the alkane, and subsequently to cool the mixture to a temperature at which the composition gels. The tempera ture to which the mixture is heated should be between 180. F. and 300 F. The mixture will be fluid above the lower temperature and the alkane will not evaporate excessively below the upper temperature. The sarcosine amides are also sufficiently stable under normal circumstancesin this range. It is preferred toheat the mixture to a temperature between 200 F. and 250 F. At these temperatures the amide is very stable and no solvent evaporates. In addition, especially above the boiling point of water, any water present in the components of the composition will be quickly evaporated off, improving the quality of the gel.

A few minutes after attainment of the proper elevated temperature a clear solution or hazy dispersion is usually obtained which turns to an opaque white on cooling to below the gelation point. While still warm andfluid the ungelled composition is poured into tubes, cans or other containers and allowedto set. Perfume or other material having relatively volatile or heat-sensitive constituents may be added to the fluid composition after some cooling thereof to decrease losses. Such addition preferably is made before pouring into end-use containers.

To use the present preferred compositions most efiiciently one firstconveniently applies a small amount of the gel to the object to be cleaned and rubs it on. No

, water or hydrophilic solvent is employed at this stage.

harmful actions of water and salt content it is desirable that they be held to less than 1% and 2% respectively. In comparatively rare instances where a thinner gel is desired or where the sarcosine amide contains more water soluble inorganic salt which it is uneconomical to remove,

more water or soluble inorganic salt than the above mums can be used, but at the expense of firmness and product stability.

The sarcosine amide salt gels of this invention are unique among such products. The salt of sarcosine amide is an extremely mild skin detergent and yet makes a satis In cleaning the hands or skin the heat of the body and the frictional heat and mechanical working all coact to promote liquefaction of the gel and improved liquid epidermis contact. The alkane solvent applied in the absence of water dissolves or loosens the lipophilic soilhclding substances on the skin and the sarcosine amide, being surface active, improves solvent-epidermis and solventsoil contact, facilitating soil removal. Because of the presence of the solvent and initial absence of water, in the applications for which they are designed and best fitted, e.g., removal of paint, grease, strongly hydrophilic soil, the gels exhibit a dissolving and cleansing action far superior to that of the ordinary synthetic detergent compositions.

After the gel has been rubbed in the components thereof are removed by rinsing with water. The sarcosine amide helps emulsify the alkane and thereby assists in its removal by the water, as well as in the removal of lipophilic soil dissolved or dispersed in the alkane. In addition the amide and water together emulsify and remove dirt and stains, especially those of a hydrophilic or lipophobic nature, which are not removed bythe alkane solvent.

After using the present compositions for cleansing the hands the skin is not dry or irritated. Instead it is smooth and supple, due to the mild "action of the sarcosine amide salt and the relatively high-boiling alkane.

the following examples are given to illustrate the present invention, They are not to be regarded as limitthe scope of the invention. All amounts and percentages'given in the specification and claims are by weight unless otherwise indicated.

were added to 82 parts of an odorless kerosene out having a boiling range between 400 F. and 450 F. (the 80% between and 90% distilled boiling over between 420 F. and 435 F.). This cut of kerosene contained a small proportion of naphthenes and less than about 1% aromatic hydrocarbons. It had a kauri butanol number of 23.5 cc. and an aniline cloud point of 196.5 F. The mixture was stirred continually while being heated from room temperature to approximately 220 F. after which it was poured into wide-mouth jars. On cooling the gel was found to be of a smooth consistency and attractive appearance. Upon rubbing on the hands it became fluid and coated the skin. When this cleaning composition was washed oif with water the hands were found to be very well cleaned and of very satisfactory soft smooth feel.

EXAMPLE H "A series of mixtures was made of fatty amide of sarccsine and an alkane solvent having a boiling range between 420 F. and 460 F. The essentially aliphatic alkane solvent had a kauri butanol number of 26.2 cc. and an aniline cloud point of 185 F. (being low in naphtheues and containing less than 1% aromatic compounds). These mixtures were heated from room temperature up to approximately 220 F., poured into containers and allowed to cool. Physical characteristics of the resulting products were noted. They are tabulated sarcosine.

Soft, good for tube dispensing. Soft excellent for tube dispensing 0. Softbgood for tube dispensing.

Do. Softbgood for jar dispensing.

MNH-HH owommooemusce Do. Soft, can be dispensed in jars.

For the gels described in the above table it was found that the firmness of the gel and the cleansing power against average greasy soil increased as the sarcosine amide content was raised. Above about 30% sarcosine amide compound the gels were so stiff as to be impracticable to dispense from jars.

EXAMPLE HI The following mixtures of sodium salt of N-lauroyl sarcosine, other synthetic detergent and 100 parts of the alkane solvent of Example II were heated to approximately 220 F. and then cooled to room temperature while quiescent. Results are shown in Table II.

Table II S thetic Deter ent Parts Fatty Amide Parts Charae ter yn g Compound of Produ ct X- Sodium lauryl sul- 40 Sodium salt of 20 Soft gel,

fate. N -1auroyl good for sarcosiue. jar dispensing. Y Nonyl phenoxy' 25 do 21 I -Do.

polyoxyethylene ethanol (Igepal 00-63 V V a Z Block copoly'mer of 50 do 13 Do.

polyoxyethylene and water-insoluble polyoxypropylene (Pluronic F-68).

Compositions of similar formulas but containing no sat-cosine compound were liquid and, consequently, were completely unsuitable for tube or jar dispensing.

All three products X, Y and Z can be packed in jars. For softer compositions for tube or jar dispensing the amount of sarcosine amide salt may be reduced.

The above invention has been described in conjunction with several illustrative examples. It will be obvious to those skilled in the art that other variations and modifications of the invention can be made and equivalents can be substituted without departing from the principles disclosed or going outside the scope of the specification and the purview of the claims.-

What is claimed is:

1. A cleansing composition in gel form comprising 50-98% of an alkane of boiling range between 350 F. and 500 F. and 250% of a water soluble salt of a. higher fatty-amide of sarcosine, the higher fatty acyl radical being of 10-18 carbon atoms, with the proportion of said sarcosine amide being sufiicient to form a gel with the alkane.

2. The cleansing composition of claim 1 in which the salt of higher fatty amide of sarcosine is the sodium salt and has a fatty acyl group of 12-16 carbon atoms.

3. A clean-sing composition in soft gel form comprising 50-98% of an aliphatic alkanc of boiling range between 350" F. and 500 F. and 2-30% of a water soluble salt of a higher fatty amide of sarcosine, the higher fatty acyl radical being of 10-18 carbon atoms, and said amide being present in the cleansing composition in proportion suflicient to form a soft gel with said alkane.

4. A cleansing composition in soft gel form comprising 50-97% of an aliphatic alkane having a boiling range between 350 F. and 500 F. and 3-15% of the sodium salt of a higher fatty amide of sarcosine, the acyl group of which is fatty acyl of 12-16 carbon atoms, in amount suincient to form a soft gel with said alkane.

5. A process for making a cleansing com-position in gel form, which comprises mixing a major proportion of an alkane having a boiling range between 350 F. and 500 F. and a minor proportion, at least 2 percent of a water soluble salt of a higher fatty acid amide of sarcosine having 1018 carbon atoms in the fatty acyl radical, at a temperature between 180 F. and 300 F. pouring the mixture into a container and lowering the temperature of the mixture to that temperature at which a soft gel containing a major amount of said alkane is formed.

6. A process for making a cleansing composition in soft gel form which comprises mixing a major proportion of an aliphatic alkane having a boiling range between 350 F. and 500 F. and a minor proportion, at least 2 percent, of a water soluble salt of a higher fatty acid amide of sarcosine, having 10-18 carbon atoms in the fatty acyl radical, at a temperature between 200 F. and 250 F. until a liquid phase is formed containing a major amount of said alkane and 3-15% of the sarcosine amide, pouring the liquid into an end-use container therefor and lowering the temperature of the liquid to that temperature at which a soft gel is formed.

(References on following page) References Citedinjhegfileofthis patent I Great Britain July 3, 1930 NITED STATES PATENTS Daimler "Feb."2, 1932 Klinkenstein Man 8, 1932 Berresford Mar.- 31, 1936 Myres June 25, 1946 Ayo Feb.,20, 1951 Lyons July 1, 1958 FOREIGN PATENTS

Claims

1. A CLEANSING COMPOSITION IN GEL FORM COMPRISING 50- 98% OF AN ALKANE OF BOILING RANGE BETWEEN 350*F. AND 500*F. AND 2-50% OF A WATER SOLUBLE SALT OF A HIGHER FATTY AMIDE OF SARCOSINE, THE HIGHER FATTY ACYL RADICAL BEING OF 10-18 CARBON ATOMS, WITH THE PROPORTING OF SAID SARCOSINE AMIDE BEING SUFFICIENT TO FORM A GEL WITH THE ALKANE.