Mild cleanser and conditioner to yield soft smooth skin

A skin cleanser and conditioner composition and particularly a facial rinse that removes soap and surfactant residue from the skin and thereby prevents irritation caused by the deposition of soaps and surfactants thereon, consisting of low levels of a nonionic surfactant, low levels of an organic acid such as citric acid/sodium citrate, and a major amount of water, which composition may be in the form of a liquid or gel.

FIELD OF THE INVENTION 
This invention relates to an aqueous skin rinse formulation for soap and 
surfactant residue removal consisting of a minimal amount of a water 
soluble nonionic surfactant such as the polyethylene oxide--condensates of 
higher fatty alcohols, and a polysorbate containing 20 moles of ethylene 
oxide, a minimal amount of an organic acid having a pKa of 4.5 to 6.5 
and/or a monovalent cation salt of the acid, and a major amount of water 
in an amount of about 84-98% by weight of the liquid formulation having a 
pH within the range of about 4.5-6.5. This product may be used as a skin 
cleanser, as an after-rinse, i.e. after the soap lather is rinsed from the 
face, or as a preshave/skin conditioner to prevent or reduce the 
deposition of shaving cream soap on the skin. The present facial rinse has 
the dual function of removing substantially all the residual soap and 
surfactant residue or preventing the deposition of soap and/or surfactant, 
and simultaneously conditioning the skin to feel soft, smooth and 
moisturized. 
BACKGROUND AND PRIOR ART 
Soap and surfactant residue which is retained on the skin after facial 
washing there-with has been shown to cause skin roughness, tightness and 
dryness. Surfactants such as alkyl ether sulfates, alkyl sulfates, alkyl 
benzenes sulfonates, and even amine oxides are potential skin irritants. 
Patch tests therewith confirm that they have the potential to irritate 
skin. 
For a surfactant to have a negative effect on the skin, it may have to be 
absorbed to, and be retained on, the skin after washing. Indeed Imokawa 
and Mishima (Nahihi Kaishi 86 473-481 (1976)) showed that skin roughness 
was related to surfactant deposition. In studying the skin feel effects of 
surfactant deposition, soap was precipitated onto the skin by adding 
calcium and magnesium salts to the wash water (i.e. increasing water 
hardness). 
In a clinical study using several consumers who washed their faces with a 
leading brand of soap in hard water (400 ppm), deionized water and soap, 
and hard water without soap, and deionized water without soap; it was 
demonstrated that facial washing with a leading brand of soap in hard 
water caused significantly more perceived tightness than washing with soap 
in deionized water. (Washing with soap and deionized water elicited some 
perceived tightness). No tightness or other skin feel characteristic was 
felt with either the hard water or deionized water without the soap. This 
study demonstrated that washing with soap generates tightness of the skin. 
An in vitro study using wool fabric and laurate soap demonstrated that Ca++ 
and Mg++ salts that produce water hardness increase surfactant deposition 
and absorption of the soap to the wool fabric, a keratin substrate. Hence, 
the water hardness increases the binding of the laurate soap to wool and, 
by analogy to skin, decreases the ability to wash the soap off the wool or 
skin, which binds the soap surfactant in a manner similarly to wool. It is 
the removal of this soap residue from the skin which is one aspect of the 
subject matter of present invention. 
Commercial facial cleansers, such as Noxema which is a white cream, and 
Olay Beauty cleanser, contain soaps as ingredients in their formulations 
which exacerbate the irritation problems associated with soap residues on 
the skin. The removal of soap residues after cleansing with soap has not 
been addressed in the prior art. However, moisturizers have been used to 
mask the negative skin sensations after washing with soap. 
The prior art discloses assorted liquid cosmetic lotions for cleansing 
purposes, as disclosed in U.S. Pat. No. 3,011,950, wherein a minor amount 
of a nonionic or anionic surfactant is dissolved in the aqueous phase 
containing a water soluble polymer and an inert gas such as oxygen, 
nitrogen or compressed air, dispersed therein to give a sparkling effect. 
U.S. Pat. No. 4,323,468 discloses a make-up remover composition for face 
and eyes comprising an oil in water emulsion containing a nonionic, 
anionic or cationic surfactant, an extract of sarsaparilla, a 
preservative, and a citrate or phosphate or lactate buffer to maintain a 
pH of 4-8.5 and preferably 6-8. U.S. Pat. No. 4,533,545 discloses cosmetic 
compositions containing polyethylene glycol derivatives as thickeners in 
the presence of a nonionic, anionic, cationic or amphoteric surfactant. 
U.S. Pat. No. 3,956,951 discloses a method of shaving which comprises 
washing the face with soap and water, rinsing all the soap from the face, 
and rubbing the wetted skin with a water-soluble solid polyethylene oxide 
polymer wafer prior to shaving with a blade type razor. U.S. Pat. No. 
4,412,943 discloses a shampoo containing an alkyl sulfate, ethylene 
diaminetetraacetate salts, and an acid such as citric acid. U.S. Pat. No. 
3,748,276 discloses aqueous gel compositions for use in cosmetics 
containing a polyether polyol gelling agent. U.S. Pat. No. 4,140,656 
discloses an anhydrous clear gel facial cleanser for removal of eye 
make-up containing mineral oil, phosphate esters and carboxy vinyl 
polymers such as a polymer of acrylic acid crosslinked with polyalkylene 
polyether (Carbopol by B. F. Goodrich Company). U.S. Pat. No. 4,360,451 
discloses amphoteric surfactant gels containing an amphoteric surfactant, 
a polyoxybutylene--polyoxyethylene block copolymer, and water for use in 
facial cleansing bath and shower gels, shampoos and the like. 
None of the prior art cosmetic compositions have addressed adverse skin 
effects of the soap residue retained on the skin, particularly the face, 
after washing with soap and water. 
It has now been found that a liquid skin cleanser, particularly a facial 
rinse/skin conditioner formulation effective in removing both soap and 
surfactant residue from the skin and reducing skin irritation and negative 
sensations of skin dryness, roughness and tightness, consists of low 
concentrations of a nonionic surfactant as the sole surfactant, and an 
organic acid (or salt thereof) such as citric acid to adjust the pH to 
that of the human skin (4.5 to 6.5), and a major amount of water, 
preferably deionized water; which may be thickened with polyethylene 
glycol--150 distearate to a thick liquid or thickened with an acrylic acid 
polymer to form a gel, and preferably contains a preservative. One such 
material comprises 1,3-dimethylol-5, 5 dimethyl (DMDM) Hydantoin and 
disodium ethylene diaminetatraacetate (EDTA). Another is Germaben II, a 
product of Sutton Laboratories, Inc. 
The use of a nonionic surfactant as one of the ingredients in a liquid 
detergent for cleaning fabrics is well known in the prior art as disclosed 
in U.S. Pat. Nos. 3,764,544; 3,959,163; and 4,206,070. 
U.S. Pat. No. 3,915,633 discloses an aqueous prewash aerosol spray soil 
release composition for use with a detergent or soap in a laundering 
operation, consisting of 1-20% by weight of an organic acid, i.e. citric 
acid, 2-30% by weight of an anionic or nonionic surfactant, water and an 
aerosol propellant. Canadian Patent No. 1,086,178 discloses a liquid heavy 
duty laundry detergent composition containing 20-70% by weight of a 
soluble ethoxylated nonionic surfactant, 0.1-1.25% by weight of a 
polyacid, i.e. citric acid, and water/organic solvents, having a pH of 
6-7.5. 
Also disclosed in the prior art are mixtures of a nonionic surfactant and 
polyacrylate thickeners in aqueous dishwashing detergent formulations as 
disclosed in U.S. Pat. Nos. 3,950,260 and 4,226,736. 
U.S. Pat. No. 4,501,680 discloses acidic liquid detergent compositions for 
cleaning ceramic tiles without eroding grout between them, comprising a 
minor proportion of glutaric acid and a lesser amount of phosphoric acid 
to provide a pH of 3-5, a minor amount of an ethoxylated fatty alcohol, a 
minor amount of a diethylene glycol monoalkyl ether, and a major amount of 
water. 
U.S. Pat. No. 4,172,140 discloses an antimicrobial composition for 
inhibiting the growth of microorganisms in an aqueous fluid medium 
comprising as the active ingredients, an admixture of 1,3-dimethylol-5,5 
dimethyl hydantoin and disodium ethylene diaminetetraacetate, for use in 
metal working fluids, cutting oil fluids, coolants, lubricants, and the 
like. 
None of the aforesaid prior art discloses a skin cleanser and skin 
conditioner or a pre or post-shave/skin conditioner consisting of a low 
level of a nonionic surfactant as the sole surfactant, a minor amount of 
an organic acid (or salt thereof) having a pKa from 4.5 to 6.5 to provide 
a pH of about 4.5 to 6.5, and a major amount of water, which may be 
thickened with polyethylene glycol--150 distearate to a thick liquid or 
thickened with an acrylic acid polymer to form a gel, and preferably 
contains a preservative system. 
SUMMARY OF THE INVENTION 
It has been found that the soap and surfactant residue retained on the skin 
after facial washing with soap causes skin damage such as dryness, 
roughness or tightness. It has additionally been found that the soap 
residue can be effectively removed from the skin with the present novel 
cleanser formulation consisting of a minor amount of a water soluble 
nonionic surfactant, with the pH adjusted to that of human skin, using an 
organic acid having a pKa from 4.5 to 6.5 and a major amount of water, 
preferably deionized water. The novel cleansers are clear products with 
viscosities ranging from watery solutions to thick gels, by the addition 
of a viscosity control agent selected from the group consisting of a 
diester of stearic acid and polyoxyethylene (PEG 150 distearate), and a 
polyacrylic acid resin (Carbopol 941). Compositions prepared with either 
thickener yield soft, smooth skin, similar to the unthickened watery 
solution, without leaving a slimy or tacky feeling. The present novel 
composition functions as a skin cleanser and conditioner, a facial rinse, 
and as a pre-shave and post-shave skin conditioner which will reduce the 
deposition of shaving cream soap on the skin and remove soap residue from 
the skin. 
This invention permits consumers to clean themselves with soap, without 
experiencing the skin effects that consumers associate with skin damage 
such as dryness, roughness or tightness. This invention represents an 
improvement over applying moisturizers to the skin, since it removes the 
irritating species (soap), rather than mask negative sensations (e.g. 
dryness). Unlike moisturizers, using this product does not leave a greasy 
film on the skin after usage. 
Accordingly, a primary object of the present invention is to provide a 
liquid skin cleanser and conditioner composition to remove soap and 
surfactant residue from the skin and thereby prevent irritation due to 
soap and surfactant. 
Another object of this invention is to provide a facial rinse/skin 
conditioner, to be used after washing with soap and water, which results 
in a soft, smooth and moisturized feel on the skin. 
Still another object of this invention is to provide a skin rinse/skin 
conditioner containing as the major ingredients, a nonionic surfactant, an 
organic acid, a major amount of water, and having a pH adjusted to that of 
human skin. 
Another object of this invention is to provide a clear liquid skin 
cleanser, facial conditioner/rinse, a pre-shave/skin conditioner or a 
post-shave rinse with viscosities ranging from watery solutions to thick 
gels. 
Another object of this invention is to provide a thickened or gelled skin 
cleanser and conditioner particularly a facial cleanser/skin conditioner 
containing a diester of stearic acid and polyoxyethylene or a polyacrylic 
acid resin as the thickening agent. 
Still another object of this invention is to provide a skin conditioner 
which does not leave a greasy film on the skin after usage. 
Another object of this invention is to provide a skin cleanser and 
conditioner or pre-shave/skin conditioner also containing a preservative 
system. 
Additional objects, advantages and novel features of the invention will be 
set forth in part in the description which follows, and in part will 
become apparent upon examination of the following specification or may be 
learned by practice of this invention. 
To achieve the foregoing and other objects in accordance with the present 
invention, as embodied and broadly described herein, the novel liquid skin 
cleanser and conditioner composition to remove soap and surfactant residue 
from the skin, of this invention, consists essentially of a major amount 
of water preferably deionized water, about 0.25-6% by weight of a nonionic 
surfactant as the sole surfactant, about 0.05-5% by weight of an organic 
acid having a pKa from 4.5 to 6.5 or a monovalent cation salt of the acid 
or a mixture of said acid and salt, said composition having a pH of 
4.5-6.5 and preferably 5-6. 
More specifically, the clear liquid cleanser/skin conditioner composition 
of the present invention, which removes soap and surfactant residue from 
the skin and simultaneously conditions the skin, consists essentially of 
about 84-98% water; about 0.7-6% by weight of a water-soluble ethoxylated 
nonionic surfactant, as the sole surfactant, selected from the group 
consisting of a polyethylene glycol ether condensate of a C.sub.8 
-C.sub.20 fatty alcohol or mixture of fatty alcohols with an average of 5 
to 30 moles of ethylene oxide, and a polysorbate having an average of 20 
moles of ethylene oxide; about 0.1-2% by weight of an organic acid, and/or 
sodium salt of the acid to adjust the pH of the compositon to about 5-6; 
about 0.5-4% and preferably 0.6-2% by weight of a thickening agent 
selected from the group consisting of a diester of stearic acid and 
polyoxyethylene, and a polyacrylic acid resin; and a preservative system, 
which might comprise 1,3-dimethylol-5,5 dimethyl hydantoin and disodium 
ethylene diamine-tetraacetate in equal amounts, or Germaben II. 
The skin cleanser of the present invention is preferably thickened to 
increase consumer acceptability by using the polyacrylic acid resin to 
form a gel, or the diester of stearic acid and polyoxyethylene to form a 
thick liquid. 
The preservative systems in the present novel compositions effectively 
preserve the product against bacteria such as B. subtilis, and mold. 
The skin cleanser of the present invention removes soap and surfactants, as 
well as dirt, oil, and other traditional soils from the skin without 
irritating the skin and face. 
The formulations in accordance with present invention can also be used to 
remove soap from other surfaces that contain keratins, or similar 
proteins, such as hair, wool, cotton and other fabrics. 
Present novel formulations may be used to remove other surfactants from 
wool and other surfaces. 
DETAILED DESCRIPTION OF THE INVENTION 
The major essential component in the liquid skin cleanser and conditioner 
compositions of the present invention is about 84 to 98% by weight water, 
preferably deionized water. The water component is essential in the 
preparation of the present stable mild facial cleansers and functions as a 
solvent or vehicle for the other active ingredients in the composition, 
which are capable of being readily rinsed from the skin. The water 
component does not attribute negative sensations to the skin. 
Another essential ingredient in the present skin cleanser is a 
water-soluble nonionic surfactant, as the sole surfactant, preferably an 
ethoxylated nonionic surfactant selected from the group consisting of a 
polyethylene glycol ether condensate of a C.sub.8 -C.sub.20 fatty alcohol 
or mixture of fatty alcohols with an average of 5-30 moles of ethylene 
oxide, and a polysorbate containing 20 moles ethylene oxide. Suitable 
fatty alcohols preferably contain 9 to 18 carbon atoms and most preferably 
11 to 15 carbon atoms. Typical examples are lauryl, tridecyl, myristyl, 
cetyl, stearyl and oleyl alcohols or mixtures thereof, which may be 
condensed with about 5 to 20 moles ethylene oxide. Typical commercial 
products are the Tergitols obtainable from Union Carbide. More 
specifically, Tergitol 15-S-9 is a polyethylene glycol ether of a mixture 
of synthetic C.sub.11-15 fatty alcohols with an average of 9 moles of 
ethylene oxide. Tergitol 25-L-7 is a polyethylene glycol ether of a 
mixture of synthetic C.sub.12-15 fatty alcohols with an average of 7 
moles of ethylene oxide. 
The polysorbates are condensates of polyethylene oxide with fatty acid 
esters or mixtures of fatty acid esters of sorbitol and sorbitol 
anhydride. Fatty acid esters include laurate esters, stearate esters, 
palmitate esters or oleate esters. The fatty acid esters of sorbitol and 
sorbitol anhydride are preferably condensed with 20 moles of ethylene 
oxide. Typical products are Tweens obtainable from the Atlas Company, also 
known as Polysorbates. More specifically, Polysorbate 20 (Tween 20) is a 
mixture of laurate esters of sorbitol and sorbitol anhydrides, consisting 
predominately of the monoester, condensed with about 20 moles of ethylene 
oxide, commonly known as Polyoxyethylene (20) Sorbitan Monolaurate. 
Polysorbate 80 (Tween 80) is a mixture of oleate esters of sorbitol and 
sorbitol anhydrides, consisting predominantly of the monoester, condensed 
with about 20 moles of ethylene oxide, commonly known as Polyoxyethylene 
(20) sorbitan monooleate. The nonionic surfactant constitutes about 
0.25-6%, preferably about 0.7-6%, and most preferably 0.5-2% by weight of 
the composition. The minimal amount of nonionic surfactant necessary for 
the aqueous rinse base to adequately remove bound soap is shown in Table 
I. 
Wool keratin was used as a good substitute for human stratum corneum to 
quantitively compare the removal of residual soap from a skin-like 
substrate with various rinse treatments. Wool keratin was pretreated with 
a solution of radiolabelled soap, rinsed with hard water to remove loosely 
bound soap, and then treated with various rinse formulations. The amount 
of soap removed from the keratin is determined by analyzing the rinse 
solutions and wool for radioactivity. 
Rinse formulations were prepared containing 2.0% citric acid, and nonionic 
surfactant (Tergitol 15-S-9) varying in concentration from 0 to 2.0%. All 
solutions were adjusted to pH 5.0. The results shown in Table I indicate 
that in the absence of surfactant, less than 20% of the residual soap is 
removed. The addition of even a small amount of surfactant increases the 
removal to almost 90%, and that a maximum in residue removal is reached at 
about 2.0.%. These results show that nonionic surfactant is necessary for 
the rinse base to adequately remove bound soap, however the amount needed 
for almost complete removal is relatively low. 
TABLE I 
______________________________________ 
Effect of Surfactant Concentration on 
Residual Soap Removal by a Rinse Formula 
Treatment* 
Removal Percent Soap 
______________________________________ 
0% Tergitol 17.9 .+-. 1.10 
0.25% Tergitol 87.0 .+-. 2.34 
0.50% Tergitol 91.4 .+-. 0.38 
0.75% Tergitol 89.5 .+-. 0.80 
1.00% Tergitol 92.9 .+-. 1.66 
2.00% Tergitol 96.4 .+-. 0.31 
______________________________________ 
*All treatment solutions contained 2% citric acid, adjusted to pH 5.0 
Another essential ingredient in the present facial cleanser/skin 
conditioner is an organic acid having a pKa value from 4.5 to 6.5, a 
monovalent cation salt of the acid, or a mixture of said acid and salt. 
The preferred acid is citric acid C.sub.3 H.sub.4 (OH)(COOH).sub.3, or a 
mixture of citric acid and a citrate salt made with a monovalent cation 
such as sodium or triethanolamine. The citric acid and/or citrate buffers 
soap removal from the skin by coacting with the nonionic surfactant in 
removing soap residue bound to the skin. Other suitable acids include 
acetic, succinic and glutaric acids. The organic acid constitutes about 
0.05 to 5%, preferably 0.1 to 2% by weight of the composition. The minimal 
amount of organic acid required to buffer soap removal from the skin is 
shown in Table II, using the pretreated wool keratin as defined above, and 
the amount of soap removed is similarly determined. 
Rinse formulations were prepared containing 0.25% Tergitol, pH 5.0, and 
citric acid concentrations varying from 0 to 2%. The results are shown in 
Table II. As can be clearly seen, citric acid is also necessary for 
adequate residue removal. The rinse base removes only 66% of the residual 
soap, while addition of the smallest amount of citric acid (0.25%) 
increases the performance of the product to 88%. The results show a 
deviation from ideal behavior, in that there is an optimum concentration 
of citric acid for maximum performance near 0.5%, followed by a decrease 
in performance as the citric acid concentration continues to increase. 
TABLE II 
______________________________________ 
Effect of Organic Acid Concentration on 
Residual Soap Removal by a Rinse Formula 
Treatment* 
Removal Percent Soap 
______________________________________ 
0% Citric Acid 
66.0 .+-. 5.4 
0.25% Citric Acid 
87.4 .+-. 0.41 
0.50% Citric Acid 
88.6 .+-. 0.27 
0.75% Citric Acid 
86.8 .+-. 1.28 
1.00% Citric Acid 
84.9 .+-. 1.30 
2.00% Citric Acid 
72.5 .+-. 6.42 
______________________________________ 
*All treatment solutions contained 0.25% Tergitol, adjusted to pH 5.0 
A preferred additive in the present skin cleanser is a thickening agent 
selected from the group consisting of a diester of stearic acid and 
polyoxyethylene (PEG 150 distearate) and a polyacrylic resin (such as 
Carbopol 941 or 940 or 1342). Carbopol 940 has rinsibility advantages over 
Carbopol 941. The Carbopol resins obtainable from the Goodrich Co., as a 
fluffy, dry powder are water soluble polymers of acrylic acid with a 
poly/functional agent, also known as polyacrylic acid resins by the CTFA 
name of Carbomers. Low concentrations of polyacrylic acid resins, about 
0.1-4% and preferably about 0.1-2% by weight, effectively thicken the 
facial cleanser and form a gel facial cleanser which is clear, colorless 
and flows slowly when poured. However, Carbopol gels lose viscosity when 
exposed to UV light. Therefore, a UV stabilizer such as benzophenone 
should be added, especially if the product is sold in a clear bottle. The 
PEG-150 distearate, in amounts of 0.1-4% and preferably 2-4% by weight, 
increases the viscosity of the watery solution to a desired thickness, 
preferaby to a thick liquid. 
It has been found that the aforesaid two viscosity control agents provide 
viscosity control without negative sensory attributes. In small, in-house 
tests, panelists reported that prototype facial cleansers prepared with 
either thickener, yielded soft, smooth skin without leaving a slimy or 
tacky feeling, similar to the use of the unthickened products. It has 
additionally been found that said two thickening agents enable the 
formulation of this product to vary within a range of viscosities, from 
watery solutions to thick gels, while maintaining the clarity as well as 
the tactile sensations afforded by the unthickened formulations. Other 
suitable thickening agents capable of maintaining the clarity and the 
tactile sensations of the unthickened formulations may be also used. 
However, it has been found that the use of the thickening agents guar gums 
and cellulose resins are unacceptable from a sensory standpoint. The 
product containing guar gum resulted in a slimy feel on the skin; and the 
product containing cellulose thickener resulted in a tacky feel on the 
skin. Accordingly, the preferred thickening agents are PEG-150 distearate 
and the polyacrylic resins. 
Another additive in the facial cleanser is a preservative system of 
1,3-dimethylol-5,5 dimethyl hydantoin (DMDM hydantoin) and disodium 
ethylene diamine tetraacetate (EDTA), preferably in equal amounts of 0.3% 
by weight of each component. This preservative system effectively 
preserves the facial cleanser of present invention against mold and 
bacteria such as B. subtilis. An aqueous solution of a combination of DMDM 
hydantoin and EDTA as an antimicrobial composition for inhibiting growth 
of microorganisms is described in U.S. Pat. No. 4,172,140, the contents of 
which are herein incorporated by reference. This patent describes the use 
of a 0.25:1 to 20:1 ratio of DMDM hydantoin to EDTA as a preservative in 
metal working fluids, cutting oil fluids and other coolants. Another 
suitable preservative is Germaben II, a product of Sutton Laboratories, 
Inc., which comprises propylene glycol 50%, diazolidinyl urea 30%, 
methylparaben 11%, and propylparaben 3%. The Germaben II preservative does 
not reduce viscosity as much as the combination of EDTA and DMDM hydantoin 
preservative, so less Carbopol is needed to achieve the same viscosity. 
The cleanser conditioner compositions of this invention also may contain 
minor amounts of conventional additional components to impart any desired 
characteristic, which are compatible with the facial cleanser formulation, 
and do not adversely affect its tactile properties and soap removal 
properties. Suitable additives include slip agents or emollients to the 
gel cleanser formulation to improve the cosmetic acceptability to 
consumers, such as polyethylene glycols up to a maximum of 6%, a copolymer 
of methyl vinyl ether and maleic hydride (Gantrez) up to a maximum of 
0.5%, and glycerin up to maximum of 1%. Silicones such as dimethicone 
copolymer up to a maximum of 2% may be added to the preshave or post-shave 
skin conditioner to enhance lubrication of the beard and reduce skin 
damage during shaving. These additives will replace some of the water in 
the formulation. 
The pH of the clear liquid facial cleanser of present invention, which may 
be in the form of a watery solution, a thick liquid, or a gel, may vary 
within the range of 4.5 to 6.5 and preferably from 5 to 6. Using the in 
vitro pretreated wool substrate described in the previous experiments to 
ascertain the effect of surfactant concentration on rinse base 
effectiveness, i.e. residual soap removal, a study of the effect of 
changing the rinse base pH was conducted. The surfactant and organic acid 
concentrations were held constant at 0.25% and 2% respectively. 
The results shown in Table III indicate that increasing the pH of the rinse 
formulation decreases the efficiency of soap removal only slightly, from 
about 90% at pH 4.5 to 83% at pH 6.5. These slight losses in product 
performance can be made up by optimization of the surfactant and organic 
acid concentrations. 
TABLE III 
______________________________________ 
Effect of pH on Residual Soap Removal by a Rinse Formula 
Treatment* 
Removal Percent Soap 
______________________________________ 
pH 4.5 89.2 .+-. 2.34 
pH 5.0 90.5 .+-. 1.90 
pH 5.5 84.2 .+-. 0.79 
pH 6.0 82.9 .+-. 0.27 
pH 6.5 83.1 .+-. 4.41 
______________________________________ 
*All treatment solutions contained 0.25% Tergitol and 2.0% citric acid 
Using the in vitro technique, efficacy of facial rinse skin cleanser 
clinical formulas in removing residual soap was evaluated. Formulas `A` 
and `C` contained 2.0% citric acid, were adjusted to pH 5.0, and had 1% 
and 6% tergitol respectively. Formula `B` contained 300 ppm hard water 
only. The results of the study are shown in Table IV, compared to the 
appropriate controls. 
TABLE IV 
______________________________________ 
Efficacy of Facial Rinse Clinical Formulas 
in Removing Residual Soap 
Percent Soap 
Treatment Removal 
______________________________________ 
Product A (1% Tergitol)* 
92.2 .+-. 1.05 
Product B (Hard Water) 13.7 .+-. 0.77 
Product C (6% Tergitol)* 
98.1 .+-. 0.30 
Control 1 (1% Tergitol, 2% Citric Acid) 
92.9 .+-. 1.66 
Control 2 (Hard Water) 14.9 .+-. 0.66 
______________________________________ 
*These formulas contained 2.0% citric acid, adjusted to pH 5.0 
The results of the soap removal study agree with the formula composition, 
i.e. hard water (`B`) removed the least soap (13.7% ), the 1% Tergitol 
formula (`A`) removed 93%, and the 6% formula (`C`) removed 98% of the 
residual soap from the wool keratin samples. The results are in agreement 
with those of the clinical study, where significant differences were found 
between the control and the test products. 
In vitro evaluations further show that the optimum formula ingredient 
levels for removing residual soap with a pH 6.0 formula were 0.54% citric 
acid and 0.77% Tergitol 15-S-9, exhibiting a 99% soap removal. 
The coaction of the nonionic surfactant, the citric acid and the pH 
provides a facial skin cleanser which optimizes residual soap removal, and 
provides a smooth, soft moisturized feel to the skin. The present novel 
facial cleanser has overcome the dry, tight, rough and flaky sensations 
after washing with soap. Test data has shown that compositions containing 
the combination of 0.5% citric acid and 0.5% nonionic surfactant removes 
about 91% soap, whereas citric acid compositions remove about 10% soap, 1% 
Tergitol (nonionic) removes about 77% soap, and the control (water only) 
removes 33.9% soap. Accordingly, the criticality of the ingredients and 
the specificity of each ingredient is necessary in the formulation of the 
present novel facial skin cleanser/skin conditioner which can also be used 
as a preshave and post-shave skin conditioner. 
The skin cleansers of the present invention are generally prepared by 
mixing the thickening agent, when used, with water until hydrated, then 
adding the nonionic surfactant and the organic acid and/or the sodium salt 
thereof, such as the citric acid and/or sodium citrate, in the water to 
form a uniform aqueous thickened solution, adding an aqueous solution of 
the preservative system to said aqueous solution with mixing, mixing until 
a homogeneous thick liquid or gel is formed, and adjusting the pH if 
necessary. 
The skin cleansers of present invention are clear, colorless, liquids which 
can be poured from any suitable container. The thin or watery liquids flow 
rapidly like water, when poured. The viscous or thick liquids flow slowly 
when poured. The gel also flows slowly when poured. 
This product is preferably used after washing the face and/or body with 
soap and water. After the soap lather is rinsed away, the cleanser of 
present invention is applied to the face and/or body by any suitable 
means. For example, the face is swabbed, using a cotton ball saturated 
with the facial cleanser, or the liquid is poured into the hands and 
rubbed onto the face. The face is rinsed with water, and dried using a 
towel.

The following examples merely illustrate the invention, but it is 
understood that the invention is not limited thereto. All amounts of 
various ingredients in the examples and elsewhere in the specification are 
by weight unless otherwise specified. 
EXAMPLES 1 and 2 
Facial Cleanser/Skin Conditioner 
______________________________________ 
1 2 
Ingredients % % 
______________________________________ 
Tergitol 15-S-9 1 6 
Sodium citrate 2.0 2.0 
Water 97.0 92.0 
pH 5 5 
______________________________________ 
These products are prepared by adding the Tergitol and the sodium citrate 
to the water and mixing until a uniform solution is obtained. 
An in vivo (clinical) study was run with both examples to test the skin 
feel after swabbing the face with each formulation subsequent to washing 
with soap and rinsing off the lather with 300 ppm (hard) water. Panelists 
reported that both products 1 and 2 left the facial skin feeling 
significantly less dry, tight and rough, and appearing less flaky after 
washing with soap compared with a 300 ppm hard water rinse. After using 
these products the facial skin felt significantly softer and smoother and 
more moisturized after washing with soap compared With a 300 ppm hard 
water rinse. Examples 1 and 2 can also be used as a post-shave 
cleanser/conditioner. 
Examples 1 and 2 were also used as a pre-shave/skin conditioner to prevent 
or reduce the deposition of shaving cream soap on the skin and thereby 
preventing or reducing skin irritation due to soap, such as tightness, 
roughness and dryness. 
In vitro studies have demonstrated that these formulations will reduce the 
deposition of up to 33% of soap from the shave cream on wool fabric. 
EXAMPLE 3 
Gel Facial Cleanser 
______________________________________ 
Ingredient % 
______________________________________ 
Sterile Deionized Water 95.9% 
Tergitol 15-S-9 2.0% 
Carbopol 941 1.0% 
Citric Acid 0.5% 
DMDM Hydantoin 0.3% 
Ethylene diamine tetra acetic acid (EDTA) 
0.3% 
100.0% 
______________________________________ 
The gel facial cleanser is a clear, colorless gel, which flows slowly when 
poured. 
This product is prepared by dissolving Carbopol (Carbomer 941) in deionized 
water then adding Tergitol (Pareth 15-9) and citric acid and mixing until 
a uniform thickened aqueous solution is obtained. DMDM hydantoin 
(Gludent-Glyco) and EDTA are added to the solution and mixed until 
completely dissolved. A gel is formed as the pH is adjusted to 6.0 with 
sodium hydroxide. 
In vivo, when panelists used the cleanser after facial washing, they 
reported that their skin felt less tight, dry and rough as well as softer, 
smoother and more moisturized compared with washing with soap. The 
cleanser contains a low level of a mild non-ionic detergent. 
This formulation can also be used as a pre-shave/skin conditioner to reduce 
the deposition of shaving cream soap on the skin, as well as a post-shave 
cleanser/conditioner to effect a softer, smoother feel to the skin. 
EXAMPLE 4 
Gel Facial Cleanser 
1.0% Tergitol 15-S-9 
0.6% Carbopol 940 (thickener) 
0.3% DMDM Hydantoin 
0.3% EDTA 
0.1% Citrate 
97.7% Sterilized Deionized Water 
pH adjusted to 6.0 with sodium hydroxide 
This gel is prepared in accordance with the procedure set forth in Example 
3. 
This product exhibits the same conditioning properties of smoothness, 
softness and moisturizing when applied as a cleanser during washing or 
after shaving with soap. 
The aforedescribed examples may be modified by the substitution of other 
nonionic surfactants for the Tergitol 15-S-9, such as Tween 20, Tween 80 
and Neodol 25-7 (Pareth 25-7-Shell), without adversely affecting the 
compositions. Likewise, PEG-distearate may be substituted for the Carbopol 
thickening agent to form a thick liquid. Also, the citric acid or citrate 
may be replaced by glutaric, succinic or acetic acid and/or the sodium or 
triethanolamine salts thereof. 
It is understood that the foregoing detailed description is given merely by 
way of illustration and that variations may be made therein without 
departing from the spirit of the invention.