US 2617754 A
Description (OCR text may contain errors)
Patented Nov. 11, 1952 COSMETIC CREAM James S. Neely, Hamilton, Ohio, assignor to The Procter and Gamble Company, Ivorydale, Ohio,
a corporation of Ohio No Drawing. Application August 29, 1949, Serial No. 113,027
This invention relates to oleaginous cosmetic cleansing creams which are readily removed from the skin by the use of water alone.
Most cosmetic cleansing creams are usually worked into the skin to loosen and dissolve dirt and are then removed either by application of soap and water or more commonly by wiping off with a cloth or tissue. One popular type of cream of this kind is essentially an emulsion of beeswax, borax, mineral oil and water, a part of the original beeswax being saponified by the borax to form a small amount of soap which acts as an emulsifying agent. This type of cold cream is recommended for skin cleansing, as an emollient night cream, as a skin lubricant, as a powder base, etc. A somewhat different type is the so-called liquefying cleansin creams, which are commonly water-free mixtures of (a) low viscosity mineral oil with (b) petrolatum, parafiin wax, ceresin, ozokerite or the like.
When removed by tissue, both of these common types of cream leave considerable amounts of oil on the skin and both are subject to the drawback of general messiness in their removal. When removed by soap and water, a drying of the skin is sometimes noticed. Furthermore, the emulsion type, which contains water, is susceptible to freezing and this frequently results in a coarsening of the cream or the development of graininess or even separation of the constituents. Also objectionable is the tendency of the liquefying type of cream to bleed free oil at normal room temperatures (i. e. at 60-100" F.) or even to separate into layers at higher temperatures.
Objects of my invention are to provide a cosmetic cleansing cream which will have the cleans ing, lubricating, softening and skin-conditioning properties of creams of the prior art, which will be non-irritating to skin or eyes, which will be pleasing in appearance and odor, which will have desirable consistency over a wide temperature range in normal usage, which will form a thin, transparent, substantially colorless oily film when rubbed on the skin, which after removal will leave the skin feeling soft but not oily or greasy, and which can easily be removed from the skin with apparent lather formation by rubbin with water alone, thus avoiding the drying effect and the skin irritation sometimes caused by soap and the general messiness and ineffectiveness of removal by a cloth or cleansing tissue. Other objects and advantages of the invention will appear in the course of the discussion which follows.
In order to attain the objects of my invention, I have found that a careful choice of ingredients must be made and that the proportions in which they are mixed are highly critical, since the de-:
sirability of the novel cream which I provide is dependent upon attaining the proper balance of mutually contradictory and opposing properties. In order to provide a cream of the desired qualities, a plurality of ingredients are necessary, each employed because of its effect on the finished cream. Each ingredient must be present in sufficient amount to impart to the finished cream the desired property, but also in amount insufiicient to produce undesirable properties or to counterbalance or neutralize desirable properties imparted by certain other ingredients. These points are discussed more fully hereinafter.
An oily constituent, liquid at and below skin temperatures, is requisite to a skin cream of the type of this invention. It should preferably be colorless, odorless, stable against deterioration on aging or when stored at elevated temperatures, and non-irritating to skin, eyes, etc. It must be of low viscosity in order that it can be spread easily over the skin without drag, stickiness or tackiness, and it must leave the skin feeling soft and cool and not dry. Light mineral oil, refined and colorless, havin a Saybolt Universal viscosity of about to 100 seconds at 100 F. (determined by American Society for Testing Materials Method D88-44) is suitable for this purpose. Such light mineral oil is the basic and largest single ingredient of the cream of my invention and constitutes at least 35 per cent by weight thereof and at least half of the liquid portion thereof.
In order to make a product of the plastic consistency of cold-cream, solid ingredients must be added to and dispersed in the liquid phase. Liq-' uid mineral oils can be firmed to a paste-like or cold-cream-like consistency by adding higherboiling petroleum fractions which are substan tially solid at normal room temperatures, such for example as parafiin wax or petrolatum, or by adding ozokerite, all of which materials will be referred to hereinafter as mineral waxes. Petrolatum of medium consistency is especially suitable for such use, having a Saybolt Universal viscosity of about to seconds at 210 R, a .capillary melting point of about '140 F., and a penetration of about -220 mm./10 by American Society for Testing Materials Method 13937-471.
Mineral waxes in general, and petrolatimi in particular, are quite soluble in mineral oils and their solubility increases rapidly with tempera-f ture, so that to a considerable degree the added wax dissolves in and becomes a part of the liquid oil portion of my creams. Creams in which mineral waxes are the sole stiffening agent are not satisfactory, since they are temperature-sensitive and, dependin upon the proportion of wax used, are either too stiff at low temperature or too soft at high temperature or perhaps both. 1 On standing at normal room temperature, such creams commonly show a tendency to leak or bleed free oil or even to separate more completely on shelf storage at elevated temperature. Furthermore, such mixtures of mineral oil and mineral wax,
even after the addition of emulsifiers. to be, discussed later, are so strongly hydrophobicv in nature that when spread on face and hands they cannot be removed by water alone. I find it desirable to limit the mineral wax content of the creams to not more than 40 per cent thereof by weight and preferably to a proportion, depending upon the nature of the mineral wax used (petrolatum is. preferred because of its ready avail ability, its .cheapness and its greater uniformity from sample to sample), such that the amount of said waxremaining undissolved and solid in the cream shall not exceed 2.0 per cent by weight of the cream. The use of the centrifuge as an analytical tool to determine the proportions of solids in my creams is tedious since the removal ofthe last traces of liquid-is difficult, hence I prefer to use the dilatometric method, which is well known. and Widely used in the vegetable, shortening industry.
'While creams of my invention require a proportion of mineral wax as a firming agent and cannot be successfully formulated without it, a second firming agent must be used in addition thereto, this second firming agent havin four characteristics the last two of which are not possessed' by-mineral waxes.
1. Melting point or range which is above the highest probable temperature of use and storage, i. e. above 120 F.
- 2.. Substantial insolubility in water.
3. Onlyslight solubility in .the oil phase at normal roomtemperature.
.4. An .amph-iphilic nature, by which I mean a nature which is both lipophilic and hydrophilic resulting from a molecular structure characterized by a hydrophilic portion which comprises or terminates in an alcoholic hydroxyl group and a lipophi-lic portion which comprises a long hydrocarbon chain, i. e. one of at least 11 carbon'atoms.
In addition, this second firming agent must be capable of crystallizing in very fine crystalline r microcrystalline form when the melt of all of the ingredients of the .cream'is chilled, these crystals or microcrystals formingamatrixor network enmeshing the liquid therein and imparting plasticity and a degree of firmness to the cream. Such material prevents great change in consistency .of the cream with change in temperature, it minimizes bleeding of free oil, and because of its dual hydrophilic-lipophilic structure it also acts to a degree as an emulsifying agent for oil and water and thus aids in removing the cream from hands and face by water alone.
I have found that the following types of organic-compounds. meet these criteria and are suitable for .use as firming agents to supplement the firming action of mineral wax:
1. Saturated normal primary aliphatic alcohols of high molecular weight (by which I mean herein. alcohols of 14 to 20 carbon atoms), hexadeca- 1101 and octadecanol being outstandingly useful examples thereof.
2. Monoamides of substantially saturated fatty acids of about 14 to 18 carbon atoms with alkylolamines of 2 to 4 carbon atoms, such for example as stearic amide of ethanolamine.
3. Monoesters of substantially saturated fatty acids of about 12 to 18 carbon atoms with saturated aliphatic' polyhydric; alcohols of 2. to 3 carbon atoms, such for example as the stearic acid monoester of ethylene glycol or glycerol.
Of these hydroxyl-bearing firmin agents, the higher alcohols are most widely useful and satisfactory, being readily available and reasonably priced, possessing the desired lipophilic-hydrophilicbalance in high degree, exhibiting little solubility in either mineral oil or water at room temperature, acting effectively as a binding agent to prevent leakage of free oil from the cream, and being an auxiliary emulsifying agent to facilitate removal of the cream from the skin by rubbing with water.
Rather unexpectedly it was found that creams made with hexadecanol are firmer at lower temperatures although, as would be expected, they are softer at higher temperatures than those made with octadecanol. For uniform consistency over wide temperature range, ootadecanol is preferred.
If the amount of these hydroxyl-bearin firming agents appreciably exceeds about 30 per cent of the cream by weight, too great hardness results, and while this can to some extent be combated by increasing the content of liquid mineral oil and/or reducing the content of solid mineral wax, these steps result in danger of leakage or bleeding of liquid oil from the cream. The lower limit for the content of hydroxyl-bearing firming agent is about 15 per cent by weight. of the cream (if the amount of such firming agent is reduced below about 15% by weight of the.
cream, the product exhibits an unattractive lardlike translucent appearance and becomes too soft) and this is set by considerations of consistency, appearance and ease of removal by Water, lower contents being associated with softness,
. translucency, sensitivity to high temperature, difficult removal by water, etc. With low content of hydroxyl bearing firming agent, larger proportions of mineral wax are called for or else some auxiliary firming agent is added, such for example as an amide of high molecular saturated fatty acids, C17H35CONH2 being illustrative thereof. When octadecanol is the hydroxyl-bearing firming agent and is present in amounts of only about 15 to 20 per cent by weight of the cream, use of auxiliary firming agents is commonly desirable (less than 1% by weight of the auxiliary firming agents has little effect on high temperature F.) consistency, while more than 5% produces a cream which is too firm at low temperature (70 F. or lower)) whereas with 25 to 30 per cent octadecanol, auxiliary firming agents are. not required.
I usually incorporate lanolin in my creams to the extent of about 2 to 4 per cent thereof by weight. This is done partly because it. frequently imparts firmness to the cream at temperatures below the melting point of lanolin, but chiefly because of its well known emollient properties. Thus creams containing it do not cause, drying of the skin and are classifiable as highly desirable skin conditioners. More than 5 per cent lanolin produces creams which are sticky or tacky when rubbed on the skin, and gives rise to color and odor problems.
In order to prepare an oleaginous wash-off leaving a white, mask-like coating when rubbed on the skin. Various monoglyceride emulsifying agents with which I have experimented have this same drawback, and I have found no satisfactory cationic emulsifiers.
The emulsifying agents which I find suitablefor my invention are those of the organic non-.
ionic amphiphilic type (the term amphiphilic having been hereinbefore defined), having both strong lipophilic nature clue to a long hydrocarbon chain and strong hydrophilic nature due to the presence of polar atoms or groups in their molecular structure, but incapable of ionizing when in aqueous solution. Such compounds possess at least one terminal alcoholic hydroxyl group the hydrophilic nature of which is supplemented by a long chain of alkylene ether groups or by some other hydrophilic groups situated between said hydroxyl group and the lipophilic portion of the molecule; they commonly contain in their molecular structure the univalent radical remaining after removing one of the two hydroxyl groups of a polyalkylene glycol. Emulsifiers of this type are much superior, for my purpose, to either anionic or cationic emulsifiers because they combine high emulsifying efliciency (thus promoting easy removal of the cosmetic cream by water), high solubility in the oils of the cream, stability on aging, freedom from color, odor or irritating action on sensitive skins or even eyes, and inertness to hard water, because they produce creams of exceptional smoothness of texture and because when such creams are rubbed on the skin they do not leave a white,
mask-like coating such as was described in the preceding paragraph.
Important members of this class of organic non-ionic amphiphilic emulsifying agents are the polyalkylene oxide derivatives, which can be represented by the general formula RXY(Z) m where R is a monovalent hydrocarbon radical of about 10 to 30 carbon atoms.
X is an ether, thioether, ester or amide linkage.
removing one hydroxyl group and at least one active hydrogen from a saturated aliphatic polyhydric alcohol of 2 to 6 carbon atoms.
Z is the monovalent residue remaining after removing one hydroxyl group from a polyalkylene glycol of at least 10 carbon atoms, there being 2 to 3 carbon atoms in each alkylene unit thereof and w is an integer, from 1 to 5.
It will be perceived that the lipophilic properties of such compounds are due essentially to the constituent designated R, while the hydrophilic properties are due essentially to the combined eifect of the remaining constituents. The following table gives some examples of radicals which I include in the above formula:
R X Y Z CmHrr- O 0 O- CH:CH20 OH2CH90 5H CasHzs- O CH: (CHzCH2O)a0H -CH2 HO OH: C|7H:5-- -S 02115 (CHg( HO)4H CH2( JHO CH: CEOHM- 'CONH --CH2CH2CH20 -(CHg( JHO)mH CLHPO C (C e) -oHzcH2on2oH,o CiaHazO OON(C H4OH) CH CHOHCH20 -CHaCHOHCHOHCH2O- 2 5 A Naphthyl Radical (I) --CH2CHCH2O- A Sterol Radical l (I) CH2CHOH( JHCH:O
A Rosin Radical 9 O (I) -CHzHCHCH207 -CHzC(CH2OH)zCHgO- -o1snor[orrcnono rronor1205 v -QH:CHOHCH ononononoaorno- Y is the polyvalent residue remaining after O nnncmw CHZOH CzHrOH l The univalent radical remaining after removing the hydroxyl group of a sterol. I A univalcnt radical remaining after removing the carboxyl group from a rosin acid such as abletrc acid or by removing the hydroxyl group from a corresponding alcohol.
More specific examples of these non-ionic, poly-alkylene oxide emulsifiers which are suitable for use in my creams are:
C1'1H35COOCH2CH2O (CH2CH20) 6H 017E350 O 0 01130110 (CHzCHzO)H 022 2 2 )aoH CnHuC O O CHZCHGH HCHO (CHZCH OM H It will be understood that neither the above general formula nor the specific examples given are exclusive, other organic non-ionic amphiphilic emulsifying agents involving radicals other than those shown being known to those skilled in the art; those shown are merely illustrative of the class as a whole. Thus instead of the ester, ether, mercaptan or amide groupings recited for X or the polyhydric alcohol residues recited for Y, other groupings can be substituted, as illustrated by the formulae:
(by reacting an alkyl ester of phosphoric acid with ethylene oxide) (by reacting an alkyl ester of glycollic acid with ethylene oxide) (by reacting an alkyl ester of lactic acid with ethylene glycol) (by reacting a fatty acid ester of glycollic acid with ethylene oxide) RCONHCHZCOO (Cal-I40) nH (by reacting a fatty acid amide of aminoacetic acid with ethylene oxide) Where n is an integer from to 30 as indicated above.
Likewise, polyglycerol chains can be substituted for polyalkylene glycol chains, or such chains can be mixed, as for example by using a mixture of ethylene oxide and propylene oxide. Similarly the hydrophilic chain can be a mixed methylene-ethylene ether chain, such as results when formaldehyde and ethylene oxide or ethylene glycol are reacted with an alcohol to give:
ROCzI-Lr (OCH2OC2H4) nOH Furthermore, the desired degree of attraction for water can be attained by using a multiplicity of amide and/or hydroxyl groups, as illustrated by the formulae:
ogroon RCON 021340 oNncznlon and owe o 0 CHzCHOHCHzOH RC 0 o-coo o CHzCHOHCHzOH mo 0 o CHzCHOHCHzOH The emulsifiers which I prefer, however, are essentially the monoesters of high molecular fatty acids (by which I mean herein those of about 12 to 20 carbon atoms) with polyalkylene glycols having at least carbon atoms in the polyalkylene glycol chain and from 2 to 3 carbon atoms in each alkylene unit thereof; for example, fatty acid monoesters of polyethylene glycol. An especially satisfactory emulsifier of this kind is the stearic acid monoester of propylene glycol, etherified with a polyethylene glycol chain of about 12 to 40 carbon atoms; such a compound results from reacting a mol of the stearic acid monoester of propylene glycol with six or more moles of ethylene oxide.
The degree of polymerization desirable in the polyalkylene glycol chains of the emulsifier depends upon the particular fatty acid used, but when the proper lipophilic-hydrophilic balance is attained the resulting cream acts as a lubricant during the wash-off procedure with water, the hands moving softly and smoothly over one another and over the face, and a foamy emulsion,
somewhat like soap lather, is formed. However, if the cream is too hydrophilic, i. e. too readily emulsified with water, it will not cling to the skin and the hands, and these will not slide over each other smoothly but rather in a jerky fashion. A thin lather and this apparent lack of lubrication result when the emulsifier is of too low molecular weight, as is the case for example with the lauric acid monoester of polyethylene glycol, the polyethylene glycol chain of which has an average molecular weight of 600. On the other hand, the stearic monoester of polyethylene glycol of this molecular weight gives a desirably heavy lather but one which is rather hard to wash off. By mixing about 3 parts of the stearic ester with one part of the lauric ester the proper emulsifying characteristics can be attained.
These non-ionic emulsifying agents are preponderantly dissolved in the liquid portion of my creams, the amount of emulsifier required depending upon the efiiciency of the particular compound selected. While about 5 per cent, based upon the weight of the cream, represents normal usage, this amount can if desired be increased to as much as 8 per cent without making the cream excessively hydrophilic, or be reduced to as little as 3 per cent before the decrease in emulsifying power, lathering and ease of removal with water becomes so great as to be objectionable. 1
Some of the emulsifiers are liquid, some solids. It will be understood that changes in the kind and in the amount of emulsifier affect the consistency of the product and require compensatory changes in the relative proportions of liquid mineral oil, solid mineral wax and hydroxyl-bearing firming agent.
Appearance, stability and odor are of vital importance in a product intended for use as a cosmeticface cream. The matter of odor can be taken care of in conventional manner by using essentially odorless raw materials of good keeping quality and by incorporating a perfume in the cream, the amounts and kind of perfume which are suitable being well known to the trade. The color of the cream should be pleasing, white creams being popular, but dyes are permissible. A translucent, lard-like appearance is in general to be avoided. This I accomplish to some extent by cooling and agitating the mixture so as to form, in situ, small crystals or microcrystals of solid mineral wax and more especially of the hydroxyl-bearing firming agent, and I can also increase whiteness and opacity by incorporating air in the cream during its preparation. However, these means are in themselves insufficient for optimum opacity, and hence I commonly supplement them by adding about 0.1 per cent to 1.0.per cent of pigment to the cream. One pigment which I find to be highly satisfactory for use in these proportions is titanium dioxide, although other insoluble pigments, such for example as zinc oxide, can of course be used. When finely divided and well dispersed, per cent by weight of TiO2 is usually ample to give the desired whiteness and opacity to the cream.
It is difiicult to wet and disperse titanium dioxide in a mineral oil system, except with very eflicient mechanical working. However, dispersion is effected and clumps or aggregates are broken up easily by first wetting the pigment with an aqueous phase before mixing it with the oil phase. I therefore find it helpful to disperse the titanium dioxide as a slurry in a mixture of water and a saturated aliphatic polyhydric alcohol containing two to three carbon atoms (such for example as ethylene glycol, propylene glycol or glycerin), to melt the rest of the system, and to mix the slurry mechanically into the molten material, chilling and continuing agitation until crystallization and solidification have progressed sufliciently to prevent sedimenta'tion of the pigment when agitation is discontinued. These polyhydric alcoholsaid indispersing the pigment and in breaking up aggregates, and they have a desirable effect on the skin, making it softer and more velvet-like. Furthermore, creams containing small amounts of Water and such'alcohols have smooth texture and a smooth and 'glossy surface which appears moistwhereas in their absenc thesurface of "the cream has an undesirably dry appearance.
From 1 to 3 per cent of the polyhydric-alcohol sufiflcies to accomplish the above-mentioned ends. The amount of water is rather sharply critical, at least per cent by weight being in general required for'ease of pigment wettingand for texture modification and in addition to have a definite whitening effect upon the cream, whereas if the amount exceeds about 2 per cent the resulting cream has th objectionable characteristic of forming a white coating when applied to the skin, instead of being transparent and colorless. A cream containing less than 2 per cent water I consider to be and shall hereafter refer to as substantially dry.
Conventional means can be used to convert the various ingredients which have been discussed into a uniform, smooth soft cream of desirable consistency. Most suitably this is done by melting all of the oily constituents and the hydroxyl-bearing firming agent, then adding successively the emulsifier'a'nd the slurry of pigment, then cooling the system by artificial means withefiicient mixing and mechanical agitation, and before solidification takes place, adding the perfume material. Refrigeration should be employed during agitation so that the rate of cooling is greater than would be the case in the absence of positive refrigeration.
This simultaneous cooling and mechanical working prevents formation of large crystals which would impart too great rigidity to the mixtureyand results'in the solidification of mineral wax and hyd'roxyl-bearing firming agent in microcrystalline form, as is evident on microscopic examination. These microcrystals confer plasticity rather than rigidity. The degree of plasticity "can be determined by conventional penetration tests wherein a measurement is made of the depth to which a needle or cone penetrates the cream under standardized conditions. The formula and the thermal and temporal treatment of the cream can then be varied as indicated by these penetration results in order to give the desired consistency. A great advantage of the-creams of my invention over most conventional creams is the small degree to which the firmness of the cream changes with change in room temperature.
The creams of my'inve'ntion are homogeneous in appearance, even though more than one phase is actually present, and when I use the term homogeneous I mean homogeneous to the naked-eye.
The following examples, in which all parts are by'weight, illustrate my inventionjbut it will 'be understood that they are illustrative only and that the invention is not limited thereby but only by the terms of the appended claims.
'12 Example 1.--A cream which I have prepared and which is illustrative of my invention had the following formula, in which all parts are by weight:
Parts by weight Mineral oil 40.3
Emulsifier 5.0 Ethylene glycol 1.5 Water 0.5 Titanium dioxide 0.5
In the above cream, the mineral oil was a colorless, odorless, low-viscosity oil, specific gravity 0.84 and Saybolt Universal viscosity of '70 seconds at F. The petrolatum was odorless, nearly white, of medium consistency (214 mum/10 penetration by A. S. T. M. method) having a Saybolt Universal viscosity of 68-69 seconds at 210 F. and melting between and F. The Octadecanol (range of values of 9 lots) melted at 133-13 F., had a hydroxyl value of -209, and acid value of 0.06-2.35. The lanolin contained 0.1% moisture, had an iodine value of 42.8, acid value of 0.56, and melting point of 98 F. The emulsifier was a propylene glycol monostearate polyethylene glycol ether having an acid value of 0.2, titer of 215 C., and hydroxyl and saponification values of 49.0 and 49.4 respectively, these latter values indicating about 36 carbon atoms in the polyethylene glycol chain. The ethylene glycol was colorless and odorless, of specific gravity 1.117.
Dilatometric measurements on this cream indicated the following approximate contents of solids at various temperatures:
Cream of the above formula, processed by suitable rapid cooling and agitation, is white, opaque and smooth, stable up to at least 90 F. and with only minor tendency to separate oil at temperatures as high as 100 F. It forms a transparent thin film when rubbed on the skin, spreading easily and with little drag 'or viscous feeling. It is easily removed from the skin by rubbing with water, when it emulsifies readily into a thick, soft, white lather which rinses easily. It cleanses the skin effectively and without any irritating effect, leaving the skin feeling soft, but not greasy. It is of plastic, creamy consistency which does not change xcessively when the temperature is varied from 60 to 100 F.
A cream of essentially the same characteristics is obtained when the emulsifier in the above formula is replaced by an alkyl benzene ether of polyethylene glycol, the alkyl group averaging about 8 carbon atoms and the polyethylene glycol chain averaging about ten C2H4O units.
Example 2.Another cream which I have prepared and which has essentially the same properties as theabove has-the formula:
- Parts by weight Mineral oil 42.83 Petrolatum 20.00 Octadecanol 25.00 Lanolin 4.50 Emulsifler 1 5.00 Ethylene glycol 1.50 Water 0.50 Titanium dioxide 0.50 Preservative 2 0.12 Perfume 0.05
1 Same emulsifier as in Example 1. I
The preservative was essentially the methyl ester of para-hydroxyhenzoic acid. A preservative proved not to be needed in this cream.
A cream of essentially the same qualities can also be prepared by substituting for the emulsifler in the above formula a mixture of 3 parts of the stearic acid monoester of polyethylene glycol and one part of the lauric acid monoester of polyethylene glycol, the polyethylene glycol chain in each case having an average molecular weight of about 600.
Examples 3 and 4.Other wash-01f creams of highly desirable properties and coming within the scope of my invention were made according to the following formulae:
Emulsifier: Essentially a stearic monoester of polymerized ethylene glycol.
I Preservative: Methyl ester of parahydroxybenzoic acid; an unnecessary ingredient in this cream.
A cream essentially similar to that of Example 3 can be made by using as the emulsifying agent a mercaptan of the approximate formula C12H25S(C2H4O)10H and by substituting the myristic acid amide of monoethanolamine for both the octadecanol and the stearic acid amide recited in that example.
A cream essentially similar to that of Example 4 can be made by using as the emulsifying agent the stearic or palmitic acid monoesters of partially anhydrized sorbitol, the free hydroxyl groups of which are condensed with polyethylene glycol chains of about ten C2H4O units each.
Examples 5 and 6.These are examples of creams made according to my invention and having in general the characteristics which were described under Example 1, but in these creams ozokerite was used in place of petrolatum.
Parts by Weight Ex. 5 Ex. 6
Mineral Oil 67. 33 61. 73 Ozokerite 3. 50 3. 60 OctadecanoL. 20.0 25.00 anolin 2.00 Stearic Amide of Monoethanolamine 1. 50 Emulsifier 1 5. 5. 00 Ethylene Glyco l. 50 1. 50 Water 0. 50 0. 50 Titanium Dioxide 0. 50 0. 50 Preservative 1 0. l2 0. 12 Perfume 0. 0. 05
1 Same emulsifier and preservative as in Examples 3 and 4,
Monostearin one of the freev hydroxyl groups of which has been etherified with a polyethylene glycol chain of about ten units can also be used as the emulsifying agent in either Examples 5 or 6 without essential change in the character of the resulting cream.
Example 7.--This cream corresponds roughly to that of Example 4, except for the use of .cetyl alcohol as the hydroxyl-bearing firming agent. It possessed the desirable qualities characteristic of the creams of my invention, although it was a little firmer than the cream of Example 4 at low temperatures (GO-70 F.) and a little softer at high temperature (-100 F.). It was made according to the formula: 1
Parts by weight fatty acid esters of ethanolamide as hydroxylbearing firming agents. They were made according to the formulae:
Parts by Weight Ex. 8 Ex. 0
Mineral OiL. 45.15 45. 05 Petrolatum. 30. 00 32. 10 Ethanolamide.. 1 17. 00 2 5. 00
Octadecanol 10. 00 Emulsifier 3 5. 00 4 5. 00 Ethylene Glyc0l 1. 50 1.50 er 0. 50 0. 50 Titanium Dioxi 0. 50 0. 50 Perfume 0. 25 0. 25
1 The ethanolamide of coconut oil fatty acids.
1 The ethanolamide of stearic acid.
3 Stearic acid ester of polyethylene glycol having about 14 ethylene oxide units therein.
4 A mixture of stearic acid ester and coconut fatty acid esters of polyethylene glycol having about 14 ethylene oxide units, there being 3 parts of the stearic acid ester to 1 part of the coconut fatty acid esters.
Both of these creams were of good. appearance and texture, and washed off the skin readily with water, although both were a little too firm at temperatures of ordinary use. That of Example 8, however, was found to be slightly irritating to some very sensitive skins.
Example 10.-This cream corresponds roughly to that of Example 8 except that it contains monostearin as the hydroxyl-bearing firming agent. It was made according to the formula:
1 Contains about 5% stearic acid.
The emulsifier was the coconut fatty acid ester of polyethylene glycol having about 7 ethylene oxide units in the polyethylene glycol chain.
This cream was of good texture, consistency and appearance, although it was judged to be '15 poorer than the cream of Example :aiinltranspareh'cy' of the film left when it was rubbed onthe skin and in ease of removal by water.
"Fromthe above description and examples it will be seen :that the "creams of my invention may, and preferably do, contain small amounts of-s'olid =.pig'ment, lanolin, perfume, water and ethylene glycol or ather low molecular liquid polyhydr'ic alcohol s'uchas propylene glycol or glycerin, but that' the essential ingredients are -'l. Light mineral oil, at least '35 per cent by weight "of the cream.
2. A solid mineral wax, not exceeding 40 per cent by weight of the cream; preferably petrolatum of medium "consistency amounting to about 1 154:0 40 per-cent by weight of the cream.
3. A firming agent having in its molecular structure both a high molecular hydrocarbon chain and an alcoholic hydroxyl group, being-of only slight solubility in either water or'mineral oil at room temperature, of high melting ,point '('i.=e. above 120 F.), and amounting to about to-30 per cent by weight of the rcream. This firming agent can be high molecular saturated normal primary aliphatic alcohols, monoamides of substantially saturated high molecular fatty acids with alkylolamines of 2 to 4 carbon atoms, or monoesters of saturated high molecular fatty acids with substantiallylsaturate'd polyh'y'dric alcoholsof 2 to? carbon atoms; preferably h'exadecanol, octadeca'nol or mixturesithereo'f.
4. An organic non-ionic amphiphilic emulsifying agent amounting to about 3 to 8 per cent by weight of the cream; preferably a monoester of a high molecular fatty acid and a polyalkylene glycol of at least 10 carbon atoms and having 2 to 3 carbon atoms in each alkylene unit thereof.
This mixture is processed by chilling and mechanical working so as to give a homogeneous product of cold-cream-like consistency which at room temperature consists of a plurality of phases, one of which is liquid and constitutes at a plastic to creamy consistency from 50 'to 100 5 .F.., spreadableto substantially a, clear film when rubbed on the human skin, and easily removable "from the skin by rubbing with water, comprising essentially a homogeneous mixture .of the .approximate general formula 40 partsby weight of light mineral oil, parts of petrolatum, 25 parts of octadecanol, 2 ,parts of lanolin, 1.5 jparts'of ethylene glycol, 0.5 part of Water, 0.5 part of titanium dioxide, and 5.0 parts of a non-ionic emulsifier which is .thestearic acid monoester of 'p'ropylene glycol etherified with polyethylene :.glycol having about .to carbon atoms-in'the .polyethyleneglycol chain thereof.
2. A cosmetic cream having plastic to creamy consistency at 60 to easily spreada'bleito a thin colorless film when rubbed on hum'anrskin and easily removable therefrom by rubbing' w ith water, whereby a creamy-lather is formed, said cream being a-homogeneous mixture comprising at least 35-per cen-t by weight of mineral oil,from 15 to 40 per cent by Weightof petrolatum, -from 1 5 to 30 per cent by weight of an alcoholic hydroxyl-bearing firming agent melting about Rand selected from the 'group-con's'i's'ting of high molecular saturated normal primary -:aliphatic alcohols, 'monoamides .of substantially saturated fatty acids of about '14 to .18 :carbon atoms with .alkylolamines of 2 to 4--carbon atoms and monoe'sters of substantially saturated fatty acids of about 12 to '18 carbon atoms with saturated aliphatic ,polyhy'dric alcohols of 2 to "3 carbon atoms, from "3 to 8 .per cent by weight of an organicv nonionic emulsifying. agenthaving balanced lipophilic and hydrophilic properties and having the formula RXY(Z)w where IR is .a monovalent hydrocarbon radical of about 10 to -30 carbon atoms, stands for a fbivalen-t structural element se'lectedIfrom the group consisting of O, S, -COO-, -LCONH-,, -CON(CH3)-, and -C'ON(C2H4OI-I)-, Y is the polyvalent residue after removing one hydroxyl group and at least one active hydrogen atom from a saturated aliphatic polyhydric alcohol of 2 to 6 carbon atoms, Z is the monovalent residue remaining after removing one hydroxyl froup from a polyalkylene glycol of at least10 carbon atoms,
there being-2 to 3 carbon atoms in 'each'a'lkylene unit thereof, and w'is an integer fromll to 5,,iand from 0.5 percent to about 2.0 per cent'wa ter, said cream consisting .at room temperature .of a plurality of phases one of which is liquidtand constitutes at least 50 per cent by weight of the cream, mineral oil constituting at 1east.50.per.cent
of this phase, and another of which phases is solid 'and comprises predominantly a mixtureof mineral Wax and higher alcohol in finely dispersed microcrystalline form.
JAMES S. NEELY.
REFERENCES CITED The following references are .of reoordin ,the file .of this patent:
UNITED STATES PATENTS Name 'Dat'e Walton Aprg23, "1935 OTHER REFERENCES Number 9 Thomssen: Modern Cosmetics (1947), pages