Stabilization of emulsion additives to nail polish removers

A nail polish or lacquer removing composition is reported which includes a volatile organic solvent such as acetone, a conditioning agent which is a C.sub.8 -C.sub.20 fatty acid or salt thereof, and a suspending polymer which is a styrene/(meth)acrylic copolymer. Absent the suspending copolymer, the conditioning agent tends to separate from the formulation.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention relates to stabilization of a lotion or cream added to a nail 
polish remover. 
2. The Related Art 
Products have long been marketed for the removal of nail polish (lacquer) 
from fingernails and toenails. Essentially, these products contain only a 
solvent(s) with which to dissolve the lacquer. Typically, the solvent will 
be a relatively volatile material such as acetone or ethyl acetate. 
Organic solvents have a tendency to remove natural oils/fats found in the 
skin. Nail polish is usually removed by applying the stripping product to 
a cotton ball and rubbing the nail. Too often surrounding skin also comes 
in contact with the solvent laden cotton ball. As a result, this contacted 
skin is defatted. To overcome the defatting phenomenon, it would be 
desirable to include ingredients within the nail polish remover that would 
counteract the stripping of oils/fats from the skin. One approach has been 
to incorporate emollients or other beneficial agents along with the 
solvent which are depositable so as to either replace or form a barrier 
for retaining the body's natural oils. 
Although not specifically directed to this problem, there have been reports 
of nail polish removers with additional nail benefit ingredients. For 
instance, U.S. Pat. No. 4,032,464 (Mausner) discloses a composition not 
only containing nail lacquer solvent but also incorporating an aqueous 
solution of a chelating agent, a humectant, a proteinaceous material and 
vitamins A and D. These ingredients are dispersed in an acetone vehicle 
thickened with Carbopol to form a homogeneous creamy stable mixture. 
EP-A-0 009 691 (Mullin et al.) reports a lacquer remover preparation held 
within and applied from a foam. Among the advantages of the foam form is 
the ready incorporation of other chemicals that would normally not be 
compatible with typical nail remover solvents. Lathering agents are said 
to be includable such as stearic acid, soaps and the like. Conditioners 
and emollients may also be incorporated such as glycerine, lanolin, 
mineral oil, fatty esters, glycols and carboxyvinyl polymer resins 
partially neutralized by triethanolamine (e.g. TEA Carbopol 941). 
Stability problems normally associated with liquid products have been 
avoided by incorporating all the ingredients within a foamed solid. On the 
other hand, there are disadvantages with foams. Unlike the small bottles 
of liquid nail remover, foam products require large containers that are 
not easily portable within a woman's handbag. Another problem is that upon 
storage there may occur separation of the liquid components within the 
foam pockets. 
Accordingly, it is an object of the present invention to provide a nail 
polish (lacquer) remover containing ingredients additional to that of 
solvent which ameliorate the problem of defatting and deliver conditioning 
oils to the skin. 
A further object of the present invention is to provide a nail polish 
(lacquer) remover that additionally contains skin conditioning agents in 
the form of a physically stable emulsion. 
These and other objects of the present invention will become more apparent 
through the detailed description of the invention that follows 
hereinafter. 
SUMMARY OF THE INVENTION 
A polish-lacquer removing composition is provided comprising: 
(i) from about 70% to about 99.5% of volatile organic solvent; 
(ii) from about 0.01% to about 5% of a conditioning agent selected from 
C.sub.8 -C.sub.20 fatty acid and salts thereof; and 
(iii) from about 0.1% to about 7% of a suspending polymer which is a 
styrene/(meth)acrylic copolymer.

DETAILED DESCRIPTION OF THE INVENTION 
The present invention provides compositions that include a major amount of 
a volatile organic solvent in combination with skin conditioning agents. 
These agents are not normally either soluble or stably dispersible within 
the solvent system. Now it has been discovered that conditioning agents 
may be stably suspended with the aid of a certain type polymer. 
Suspending polymers suitable for the present invention are those of the 
styrene/(meth)acrylic copolymer variety. These copolymers may optionally 
be cross-linked with such agents as divinylbenzene. Specific examples are 
styrene/acrylate copolymer (Lytron 614 and 621), 
styrene/acrylate/divinylbenzene copolymer (Lytron 284, 288 and 295), and 
styrene/PEG-10 maleate/nonoxynol-10 maleate/acrylate copolymer (Lytron 
305). Most preferred are the type of copolymers exemplified by Lytron 295 
and 621, the latter being especially preferred. Suspending polymer will 
normally be present in an amount from about 0.1% to about 7% by weight of 
the total composition. Preferably, the amount will range from about 0.5% 
to about 5%, optimally about 1% by weight. 
Volatile organic solvents employed for the present invention will have a 
boiling point lower than 100.degree. C., preferably below 50.degree. C. 
Acetone and ethyl acetate are the solvents of choice. These may, however, 
be utilized in combination with other solvents such as methyl ethyl 
ketone. Amount of the solvent will range from about 70% to about 99.5% by 
weight of the total composition. Preferably, the amount will range from 
about 78 to about 88%, optimally, about 80% by weight. 
Water may also be present in the compositions. Amounts of water may range 
anywhere from a trace up to about 25%, preferably from about 8% to about 
15%, optimally between about 10% and 13% by weight. 
Of course, a key feature of the composition is the presence of a 
conditioning agent. This agent is defined herein as a C.sub.8 -C.sub.20 
fatty acid or salt thereof. Typical fatty acids include lauric, myristic, 
oleic, stearic acids and mixtures thereof; preferably the acid or salt is 
based upon stearic acid. Typical fatty acid salts are those with cations 
such as sodium, potassium, diethanolammonium, triethanolammonium, ammonium 
ions and mixtures thereof. Conditioning agents will be present in an 
amount from about 0.01% to about 5%, preferably from about 0.05% to about 
1% by weight of the total composition. 
Optionally, there may be included within the compositions of the invention 
humectants such as glycerine, propylene glycol, sorbitol and mixtures 
thereof. Amounts of these components may range from about 0.1% to about 
10% by weight of the total composition. 
Emollients such as fatty acid esters (e.g. glycol and diglycol stearate, 
glycerol stearate, cetyl acetate), mineral oil, silicone oil, lanolin and 
lanolin derivatives may be present in amounts from about 0.01% to about 3% 
by weight of the total composition. 
Conditioning agent, emollient and other oily materials are normally first 
prepared as an oil-in-water emulsion. This emulsion is then incorporated 
into the volatile organic solvent. Typical amount of the emulsion may 
range from about 1% to about 10% of the total composition. 
The following Examples will more fully illustrate the embodiments of this 
invention. All parts, percentages and proportions referred to herein and 
in the appended claims are by weight of the total composition unless 
otherwise stated. 
EXAMPLE 1 
A composition typical of the present invention is outlined in Table I. 
TABLE I 
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Ingredient Weight % 
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Acetone 75-85 
Water 10-15 
Glycerine 1-8 
Lytron 621 0.5-2 
Fragrance and Color 0.5-2 
Mineral Oil 0.01-0.5 
Carbopol 934 (2% dispersion) 
0.01-0.5 
Propylene Glycol 0.01-0.5 
Stearic Acid 0.01-0.5 
Glycol Stearate 0.01-0.5 
Cetyl Acetate 0.01-0.3 
Triethanolamine 0.01-0.3 
Glycerol Stearate 0.01-0.2 
Cetyl Alcohol 0.01-0.1 
Methyl Paraben, Propyl Paraben and 
0.01-0.1 
Disodium EDTA 
Magnesium Aluminum Silicate (Veegum) 
0.01-0.05 
Silicone Fluid 0.01-0.05 
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EXAMPLE 2 
Absent the presence of Lytron 621 as a suspending agent, the formula of 
Table I exhibited precipitation of white particles. Solubility tests were 
conducted to investigate which of the various non-solvent components was 
incompatible with the formulation. A test solution was prepared from 89.9% 
acetone, 10% water and 0.1% additive. Table II lists the results of 
solubility tests on the various additives. 
TABLE II 
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Additive Compatibility 
Additive Precipitate Formation 
______________________________________ 
Stearic Acid Severe 
Veegum Moderate 
Silicone Fluid Slight 
Glycerine Slight 
Mineral Oil None 
Cetyl Alcohol None 
Glycol Stearate 
None 
Glycerol Stearate 
None 
Triethanolamine 
None 
Carbopol 934 None 
______________________________________ 
From the above Table, it is evident that the major insoluble component is 
that of stearic acid. 
EXAMPLE 3 
Suspending performance of various polymers was investigated. The formula 
outlined in Table I was employed with the exception that the type of 
Lytron was varied. 
TABLE III 
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Effect of Various Lytron Polymers 
Polymer Precipitate 
Chemical Identity Trademark Formation 
______________________________________ 
Styrene/Acrylate copolymer 
Lytron 621 
Trace 
Styrene/Acrylate/divinyl- 
Lytron 295 
Very slight 
benzene copolymer 
Styrene/Acrylate Copolymer 
Lytron 614 
Slight-Moderate 
Styrene/PEG-10 Maleate/ 
Lytron 305 
Moderate 
Nonoxynol-10 Maleate/ 
Acrylate Copolymer 
Styrene/Acrylamide 
Lytron 308 
Severe 
Copolymer 
Styrene/Acrylate/PEG-10 
Lytron 300 
Phase Separation 
Dimaleate Copolymer 
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The Lytron materials were all obtained from the Morton Chemical Division of 
Morton-Thiokol Corporation, of Chicago, Ill. From Table III, it is evident 
Lytron 621 provided the best suspending activity. Lytron 295, a 
cross-linked material, was somewhat less effective. Unacceptable 
suspending properties were noted for the Lytron 305, 308 and 300 
materials. 
EXAMPLE 4 
Illustrated in this Example is the effect of altering the level of the 
suspending polymer. Lytron 295 was substituted for Lytron 621 at various 
levels in the formulation outlined under Table I. Results are reported in 
Table IV. 
TABLE IV 
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Polymer Concentration Effects 
Level of Suspending 
Polymer (Percentage) 
Precipitate Formation 
______________________________________ 
0.5 Some separation 
1.0 Very slight separation 
1.5 Trace separation 
2.0 No separation 
2.5 No separation 
10.0 Separation 
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From the results, it is evident that there is an effective range for the 
suspending polymer of between 0.5% to upwards of 2.5% but less than 10% by 
weight. 
The foregoing description and Examples illustrate selected embodiments of 
the present invention and in light thereof various modifications will be 
suggested to one skilled in the art, all of which are in the spirit and 
purview of this invention.