MXPA03002869A - Compositions for cleansing skin and treating acne. - Google Patents

Abstract

A skin cleansing composition comprising: from about 0.1 to about 5 percent by weight of at least one anti-acne active ingredient; from about 1 to about 25 percent by weight of at least one alcohol; from about 0.1 to about 15 percent by weight of at least one solubilizer; and water is disclosed. The composition is stable and dries quickly, but does not make the skin feel dry after use.

Description

COMPOSITIONS FOR SKIN CLEANSING AND ACNE TREATMENT BACKGROUND OF THE INVENTION FIELD OF THE INVENTION The present invention relates to compositions that are useful for cleansing the skin and for treating acne. The compositions contain salicylic acid, have a low alcohol content, are physically stable, and do not leave a dry skin feeling after use.

DESCRIPTION OF PREVIOUS TECHNIQUE Acne is a common disorder characterized by pimples, infected follicles, papules, pustules, cysts, and various nodules and scars. Acne is commonly seen on the face and back of the arm. It is theorized that acne is caused, at least in part, by bacteria such as Propionbacterium acnes. For this reason, anti-acne products frequently contain active ingredients that eliminate or inhibit the growth of bacteria. Benzoyl peroxide and salicylic acid are well known for their use as anti-acne active ingredients.

Acne can be quite unpleasant and often causes embarrassment to the person who has it. For this reason, as well as for good hygiene habits, many people use skin cleansers and anti-acne products daily. Skin cleansing products include astringents, organic pigments, and the like. Anti-acne products include ointments, lotions, and the like. The astringent and organic pigment formulations sometimes include anti-acne active ingredients. It is known that skin cleansing products and anti-acne products contain water. Salicylic acid is sparingly soluble in water. Therefore, when it is desired to formulate salicylic acid in a cleaning product or in an anti-acne product, it becomes a challenge to keep the salicylic acid in solution. The formulations are frequently physically unstable, that is, the salicylic acid is precipitated from the solution. Due to this poor solubility in water, salicylic acid is frequently formulated with a relatively high amount of ethyl alcohol to help solubilize salicylic acid. As used in the present invention, the term "relatively high amount of ethyl alcohol" means from 40 to 80% by weight of ethyl alcohol, based on the total weight of the formulation. Ethyl alcohol in salicylic acid formulations is also used to help create formulations that dry quickly on the skin. The formulations tend to dry quickly due to the evaporation of ethyl alcohol. Unfortunately, the evaporation of ethyl alcohol from the skin tends to dry the skin. In general, people like to feel their skin moist after cleansing. Therefore, there is a need for a skin cleansing product that contains an active anti-acne ingredient, but does not produce a dry feeling on the skin after use. Attempts have been made to develop alcohol-free skin cleansers containing anti-acne active ingredients, however various problems are associated with the formulations. One problem is that it is difficult to make a stable formulation, since salicylic acid tends to precipitate out of the solution. Another problem is that the formulations do not dry up so fast, due to the absence of ethyl alcohol. When the alcohol-free formulations dry completely, a feeling of stickiness often remains on the skin. U.S. Patent No. 6, 024, 941 discloses external skin treatment compositions comprising vitamin A and at least one stabilizer for vitamin A. Suitable stabilizers include a salicylic acid compound and a polyethylene glycol. It is shown that the compositions are useful for the treatment of keratodermatitis and for the prevention of or treatment of dermal aging. There is no teaching or suggestion of compositions for cleansing the skin that are physically stable, that contain an anti-acne ingredient and that have low levels of alcohol or the benefits thereof. Accordingly, there is a continuing need for a skin cleansing product containing an active anti-acne ingredient, which is physically stable, and which does not produce a dry or sticky feeling on the skin after use.

BRIEF DESCRIPTION OF THE INVENTION The inventors have discovered that it is possible to provide a cleansing product for the skin, which contains an active anti-acne ingredient, which is physically stable, and which does not produce a feeling of dryness or stickiness after use. The present invention provides a composition for cleansing the skin including: from about 0.1 to about 5 weight percent of at least one active anti-acne ingredient; from about 1 to about 25 weight percent of at least one alcohol; from about 0.1 to about 15 weight percent of at least one solubilizer; and water.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES The invention relates to a physically stable composition for cleansing the skin including: from about 0.1 to about 5 weight percent of at least one active anti-acne ingredient; from about 1 to about 25 weight percent of at least one alcohol; from about 0.1 to about 15 weight percent of at least one solubilizer; and water. In the context of this invention, the term "physically stable" means compositions that are transparent and do not form separate phases or precipitate at room temperature. The skin cleansing compositions of the present invention include at least one anti-acne active ingredient. Suitable anti-acne active ingredients include, but are not limited to, salicylic acid, sulfur, lactic acid, glycolic acid, pyruvic acid, urea, resorcinol, N-acetylcysteine, retinoic acid, benzoyl peroxide, octopirox, triclosan, azelaic acid , phenoxyethanol, phenoxypropanol, favinoids, derivatives thereof, and combinations thereof. Salicylic acid and benzoyl peroxide are preferred. Salicylic acid is the most preferred. The amount of anti-acne active ingredient in the composition of the invention may have a range of from about 0.1 to about 5, preferably from about 0.5 to about 2 weight percent, based on the total weight of the composition. At least one alcohol is included in the compositions of this invention. The alcohol can be selected from ethanol, n-propanol, isopropanol, t-butyl alcohol, and combinations thereof. Ethanol is preferred. The amount of alcohol in the compositions of the invention is sufficiently high for the compositions to dry quickly and leave no sticky feeling on the skin, however, not so high that the skin feels dry after cleaning with the compositions . The amount of alcohol in the compositions of the invention may have a range of from about 1 to about 25, preferably from about 5 to about 20, more preferably from about 10 to about 20 weight percent, based on the total weight of the composition . At least one solubilizer is included in the compositions of the invention to stabilize the composition so that the active anti-acne ingredient is not precipitated from the solution under normal storage conditions. Suitable solubilizers include, but are not limited to, propylene glycol, butylene glycol, hexylene glycol, polyethylene glycol ("PEG"), polylorbate-20, polysorbate-40, isoceteth-15, isoceteth-20, isoceteth-30, sorbeth-20, sorbeth- 40, PEG-40, castor oil, and combinations thereof. The most preferred solubilizer is PEG. It has been found that the number of repeat units in the PEG affects the performance of the PEG as a solubilizer for active anti-acne ingredients. If the number of repeated units is too high or too low, the formulation will become cloudy, and will not be physically stable. Generally, suitable PEG's include PEG's having from about 20 to about 75 repeating units of ethylene glycol, preferably 20, 32, 40, 55, 60, and 75, more preferably, 20, 32, and 40, more preferably 32 repeating units of ethylene glycol. The amount of solubilizer in the compositions of the invention may have a range of from about 0.1 to about 15, preferably from about 0.5 to about 10, more preferably from about 1 to about 5 weight percent, based on the total weight of the composition . Water is also included in the compositions of the invention. The amount of water used will depend on the amounts of the required components and any optional components in the formulation. Generally, the amount of water can range from about 60 to about 99, preferably from about 75 to about 85 percent by weight, based on the total weight of the composition. The skin cleansing compositions of the invention optionally include humectants, UV absorbers, pH adjusting agents, skin relief agents, emollients, preservatives, conditioning agents, and fragrances. The emollients that can be included in the compositions of the invention function by their ability to remain on the surface of the skin or in the stratum corneum to act as lubricants, to reduce the peeling of the skin, and to improve the appearance of the skin . Typical emollients include fatty esters, mineral oil, polyether siloxane copolymers and the like. Examples of suitable emollients include, but are not limited to, polypropylene glycol ("PPG") - 15 stearyl ether, PPG-10 cetyl ether, steareth-10, oleth-8, PPG-lauryl ether, vitamin E acetate, PEG- 7 glyceryl cocoate, lanolin, and combinations thereof. Vitamin E acetate, PEG-7 glyceryl cocoate and combinations thereof are preferred. When used, the emollient may be present in an amount of from about 0.01 to about 5, preferably from about 0.1 to about 2, more preferably from about 0.1 to about 1 weight percent, based on the total weight of the composition. The polyhydric alcohols can be used as humectants in the compositions of the invention. The humectants help to increase the effectiveness of the emollient by reducing the desquamation of the skin, stimulating the removal of residues of desquamation and improving the sensation of the skin. Suitable polyhydric alcohols include, but are not limited to, glycerol (also known as glycerin), polyalkylene glycols, alkylene polyols and their derivatives, including propylene glycol, dipropylene glycol, polypropylene glycol, polyethylene glycol and derivatives thereof, sorbitol, hydroxypropyl sorbitol, hexylene glycol, 1,3 dibutylene glycol, 1,2,6-hexanetriol, ethoxylated glycerol, propoxylated glycerol and mixtures thereof. Glycerin is preferred. When used, the humectant is present in an amount of from about 0.1 to about 5, preferably from about 0.1 to about 3 weight percent, based on the total weight of the composition.

The skin relief agents can be added to the compositions of the invention. Suitable skin relief agents include, but are not limited to, panthenol, bisabolol, allantoin, and combinations thereof. When used, the skin relief agent is present in an amount of from about 0.01 to about 0.75, preferably from about 0.01 to about 0.1 weight percent, based on the total weight of the composition. Conditioning agents can also be added to the compositions of the invention. Suitable conditioning agents include, but are not limited to, dimethicone propyl PG-betaine, dimethicone copolyols, polyquaternium-10, and combinations thereof. When used, the conditioning agent is present in an amount from about 0.01 to about 1, preferably from about 0.01 to about 0.5 weight percent, based on the total weight of the composition. It has also been found that the pH of the compositions according to the invention has an effect on the physical stability of the composition. Generally, the pH of the compositions of the invention has a range from about 3 to about 4, preferably from about 3.25 to about 3.75. more preferably of about 3.6. The pH can be adjusted by the use of cosmetically acceptable pH adjusters, such as, but not limited to, sodium citrate. The amount of the pH adjuster used will depend on the initial pH of the composition and the volume of the composition to be adjusted. Generally, the amount used of pH adjuster may have a range of from about 0.1 to about 0.5, preferably from about 0.2 to about 0.4 weight percent, based on the total weight of the composition. The UV absorbers can be added to the compositions of the invention. Suitable UV absorbers include, but are not limited to, benzophenone and its derivatives, cinnamic acid and its derivatives, azoles, imidazoles and the like. When used, the amount of UV absorber can have a range from about 0.001 to about 0.01 weight percent, based on the total weight of the composition. Botanical extracts, such as aloe barbadensis extract, chamomile extract, thyme extract, rosemary extract, and the like may also be useful in the compositions of the invention. When used, botanical extracts are present from about 0.01 to about 1, preferably from about 0.01 to about 0.1 weight percent, based on the total weight of the composition. Agents perceived by the senses, such as menthyl lactate, menthol, camphor, peppermint, eucalyptus oil, mentoxipropanediol, and the like can also be used in the compositions of the invention. When used, agents sensed by the senses are present from about 0.01 to about 1, preferably from about 0.05 to about 0.5 weight percent, based on the total weight of the composition. The preservatives are typically added to the compositions to inhibit the growth of microbial organisms. Suitable preservatives to be added to the compositions of the invention include benzoic acid, and Quaternium-15, commercially available as "Dowicil 200" from the Dow Chemical Corporation of Midland, Michigan. Benzoic acid is preferred. When used, the preservative is present in an amount of from about 0.01 to about 1, preferably from about 0.05 to about 0.5 weight percent, based on the total weight of the composition. Any fragrance can be added to the compositions of the invention for aesthetic purposes. Suitable fragrances include, but are not limited to, eucalyptus oil, synthetic camfor, peppermint oil, clove oil, lavender, chamomile and the like. When used, the fragrances are present in an amount of from about 0.05 to about 0.5, preferably from about 0.1 to about 0.3 weight percent, based on the total weight of the composition. The dyes can also be added to the compositions of the invention for aesthetic purposes. Suitable colorants and typical usage levels are well known in the art.

The compositions of the invention are useful for cleansing the skin and treating acne. The compositions can be supplied as a liquid, which can be applied to the skin using swabs, cotton cloths, and the like. Alternatively, the composition can be absorbed into handkerchiefs, which are known in the art, and sold as handkerchiefs for cleaning. The advantages of the invention and specific embodiments of the compositions prepared in accordance with the present invention are illustrated by the following examples. It will be understood, however, that the invention is not confined to the specific limitations set forth in the individual examples, but rather is limited to the scope of the appended claims.

Materials used in the examples Registered Name Active Provider Glycerine 916 Glycerin Henkel Univul MS-40 Benzophenone-4 BASF Ritapan DL Panthenol RITA Actiphyte of Aloe Vera Aloe extract Active Organics barbadensis Carbowax PEG Polyethylene glycol Union Carbide Arlasolve 200 lsoceteth-20 Uniquema Cetiol HE PEG-7 glyceryl cocoate Henkel Frescolat MR Mentil lactate Haarmann & Reimer Dow Corning 345 Fluid Cyclomethicone Dow Corning Abil B 9950 Dimethicone propyl PG- Goldschmidt betaine Abil AV 20HS Phenyl trimethicone Goldschmidt Abil Wax 9801 Cetyl dimethicone Goldschmidt Abil B 8832 Copolyol dimethicone Goldschmidt Name registered Active Provider Abil B 8843 Copolyol dimethicone Goldschmidt Arlamol E PPG-15 stearyl ether ICI Surfactants Procedures AWS PPG-5-ceteth-20 Croda Solubilizant LRI PPG-26-buteth-26 and Wackherr hydrogenated castor oil with PEG-40 Polymer JR 400 Polyquaternium- 10 Amerchol Tween 20 Polysorbate 20 Uniquema Carbomer EX518 Acrylate copolymer BF Goodrich EXAMPLE 1 In the example, the oil phase and the aqueous phase were prepared separately, and then combined. The samples were mixed and stored at room temperature. The samples were monitored visually. For a sample to be considered useful, the formulation must be transparent and no precipitate should be formed at room temperature. The procedure for preparing the samples was as follows (all amounts are based on one percent by weight): The oil phase was prepared by the combination of vitamin E acetate, Arlamol® E, and Dow Corning Fluid 345 and mixed well . The aqueous phase was prepared by melting PEG 1450 in a beaker, adding salicylic acid and mixing until dissolved, adding ethyl alcohol and mixing. In a separate container, Carbomer EX-518 was added to the water, with mixing. The solution containing the alcohol was added to the solution containing the water and mixed to form the aqueous phase. The oil phase was then combined with the aqueous phase and mixed. The following samples were prepared: * PEG 1450 = Polyethylene glycol containing 32 repeating units of ethylene glycol and having a molecular weight of 1450. The samples were monitored for physical stability. The results were as follows: Sample 1 - It formed a cloudy emulsion, it took more than three hours for the phase to be separated. Sample 2 - Salicylic acid was precipitated when the oil phase and the aqueous phase were combined. Sample 3 - It formed a cloudy emulsion, it took more than three hours for the phase to be separated. Sample 4 - It formed a cloudy emulsion, it took more than three hours for the phase to be separated.

Sample 5 - Formed a cloudy emulsion, the phase separated quickly after adjusting the pH. Sample 6 - Formed a cloudy emulsion, the phase separated within the first 5 minutes. Sample 7 - Formed a cloudy emulsion, the phase separated.

EXAMPLE 2 The following formulations were prepared by the following process: The beaker was charged with water and glycerin and mixed. An alcohol phase was prepared by melting PEG 1450, adding salicylic acid and mixing until dissolved. The alcohol was added to this solution with mixing. An oil phase was prepared by the combination of vitamin E acetate, vitamin A palmitate, fragrance, and Procetyl® AWS or Aslasolve® and mixed. The alcohol phase was then added to water and glycerin and mixed. The oil phase was then added to the water / alcohol phase mixture and mixed.

* For sample # 11, a portion of the alcohol phase was added to the oil phase, and then the phases were combined. The samples were monitored for physical stability. The results were as follows: Sample 8 - Opaque emulsion Sample 9 - Opaque emulsion Sample 10 - Transparent solution Sample 11 - Turbid, yellow oil phase, phase separation. Sample 10 was physically stable at room temperature, and was observed transparent.

EXAMPLE 3 Accelerated aging studies Storage conditions vary due to season and geographic location. Therefore, it is useful to evaluate the main candidate formulations both at high temperatures (summer storage conditions) and at low temperatures (storage conditions in winter). The following formulations were evaluated for accelerated aging. For these studies, samples were stored at 4 ° C, at room temperature (~ 25 ° C), 40 ° C, and 50 ° C. In addition, samples were stored at -4 ° C for a minimum of 24 hours, then stored at room temperature for 24 hours, and evaluated. This freeze / thaw evaluation was repeated for a total of three cycles. The samples were visually inspected. The samples did not pass the test if they presented phase separation, if they became turbid, if they formed a precipitate, or if they changed color.

The results are as follows: After 5 days of storage, sample 12 was observed to be transparent both at 4 ° C and at room temperature, but turned turbid at 40 ° C and very cloudy both at 50 ° C and after a cycle of freezing / thawing. Sample 13 was observed to be transparent both at 4 ° C and at room temperature, but turned turbid at 40 ° C and very cloudy both at 50 ° C and after a freeze / thaw cycle. All samples were also scented to determine if the storage to observe accelerated aging had any adverse effect on the fragrance. No difference in the odor of the fragrance was evident in any sample.

EXAMPLE 4 A base formulation was as follows: A beaker was charged with water and glycerin and mixed, benzophenone was added and mixed. A pre-mix of molten PEG-1450, salicylic acid, alcohol, and benzoic acid was performed. To the water mixture, the pre-mix was added and mixed; the pH was adjusted to 3.5 with sodium citrate; the dyes were added. The base formulation contained the following ingredients (all by weight percentage): 10% ethanol, 1% glycerin, 0.005% benzophenone-4, 0.5% salicylic acid, 1% PEG-1450, 80% water, 0.1 % benzoic acid, 0.035% FD &C blue # 1 (0.1% solution), 0.015% FD &C yellow # 10 (0.1% solution), and 0.35% sodium citrate. The samples were then made by the combination of menthyl lactate and the fragrance, and heated until the menthyl lactate was melted; the solubilizer was added and mixed; and the mixture was added to the base formulation and mixed. The following samples were made from sub-samples of the base formulation: Sample number Inquired 14 15 16 17 18 19 Base formulation 98.8 99.1 98.8 93 93 93 Menthyl lactate 0.1 0.1 0.1 0.1 0.1 0.1 Fragrance O 0.2 0.2 0.2 0.2 0.2 0.2 Solubilizer LRI 0.9 0 0 0 0 0 Arlasolve 200 0 0.6 0.9 0 0 0 ProceStyl AWS 0 0 0 0.61 0.90 1.21 Samples 17 and 18 were cloudy. Samples 14, 15, 16, and 19 were transparent and stored for accelerated aging studies. The results were as follows: after 1 day of storage, all samples 14, 15, 16 and 19 were transparent at 50 ° C and at room temperature. Samples 14 and 16 were clear after a freeze / thaw cycle, and samples 15 and 19 were cloudy after a freeze / thaw cycle.

EXAMPLE 5 A large beaker was charged with water, glycerin was added and mixed, benzophenone was added and mixed, sodium citrate was added and mixed. A pre-mix of salicylic acid was prepared by melted PEG-1450, solubilizer was added and heated to about 40 ° C, salicylic acid was added and mixed until the salicylic acid was dissolved. The mixture was cooled to 40 ° C, then menthyl lactate was added and mixed until dissolved, vitamin E acetate was added and mixed, benzoic acid was added and mixed; the alcohol was added and mixed, and the fragrance was added and mixed. The pre-mix of salicylic acid was added to the water solution and mixed, then the dyes were added and mixed.

The sample contained 85.6% water, 1% glycerin, 0.005% benzophenone-4, 1% PEG-1450, 0.5% salicylic acid, 10% ethanol, 0.1% benzoic acid, 0.35% sodium citrate , 0.044% FD &C blue # 1 (0.1% solution), 0.112% FD &C yellow # 10 (0.1% solution), 0.1% menthyl lactate, 0.2% fragrance, 0.1% acetate vitamin E, and 0.9% of LRI solubilizer. The formulation was maintained in a single phase and was transparent. After 5 weeks of storage, the samples at 4 ° C, 25 ° C, 40 ° C, and 50 ° C remained clear.

EXAMPLE 6 Comparison of Solubilizers The following samples were made following the procedure of Example 4: * = Used panthenol powder instead of 70% active liquid. Samples 20, 21, and 22 were transparent, and samples 20 and 21 were stored for accelerated aging studies. The results were as follows: after 4 and 1/2 weeks of storage, samples 20 and 21 were kept transparent at room temperature, 4 ° C, 40 ° C, and 50 ° C. Both samples 20 and 21 were kept transparent, after three freeze / thaw cycles.

Sample 23 remained transparent, therefore accelerated aging studies were carried out in it. The results were as follows: after eight weeks of storage, sample 23 remained clear at room temperature, 4 ° C, 40 ° C, and 50 ° C, and after three freeze / thaw cycles. observed opaque, therefore no studies of accelerated aging in this one.

EXAMPLE 7 Addition of compounds containing dlmeticone Subsamples were taken from sample 22 and evaluated for compatibility with dimethicone-containing compounds. The samples were prepared to see if the cleaning properties of the The formulation could be improved after the addition of dimethicone-containing compounds. The samples were prepared by adding the silicone-containing compound to the sub-sample and mixed. They prepared The following samples: Sample number Inqredient 25 27 28 29 30 Sample 22 (sub- 99.9 99.9 99.5 99.995 99.9 98.75 sample) Abil B 8832 0.1 0 0 0 0 0 Abil B 8843 0 0.1 0.5 0 0 0 Polymer JR 400 0 0 0 0.005 0 0 Abil B 9950 0 0 0 0 0.1 0 Glycolic acid 0 0 0 0 0 1 Sodium Citrate 0 0 0 0 0 0.25 Sample 25 was cloudy. Sample 27 was slightly cloudy. Samples 26, 28 and 29 were kept transparent. Some of the samples were applied to a person's arm. The skin did not feel different, remarkably, after cleaning with these samples and when they were cleaned with sample 22. Accelerated aging studies were not carried out on these samples. It was subsequently determined experimentally that the dimethicone-containing compound is better integrated into the solution when it is added to the salicylic acid premix, just after the addition of the ethanol.

EXAMPLE 8 Adjustment of the levels of chin lactate and fragrance A series of samples was prepared to optimize the levels of menthyl lactate and the fragrance in the formulation. Samples were prepared by preparing a pre-mix of Carbowax PEG-1450, Arlasolve 200, salicllico acid, vitamin E acetate, Cetiol HE, benzoic acid, Frescolat MR, ethanol, and fragrance; and a main batch of water, glycerin, Univul MS-40, sodium citrate, FD &C blue # 1 (0.1% solution), FD &C yellow # 10 (0.1% solution), Ritapan DL, and Actifito de Aloe vera; then the main lot and the pre-mix were combined. The following samples were prepared: Samples were stored at room temperature, 4 ° C, 40 ° C, and 50 ° C and were evaluated for their odor. During the time, no change in odor was detected for any sample, except at 50 ° C, where all 4 samples had a slight odor of alcohol. After three freeze / thaw cycles, no change in odor was detected for any sample, except for sample 33, where a slight odor of alcohol was evident after two and three cycles.

EXAMPLE 9 The effect of PEG v variation of pH The following samples were prepared to compare the effect of PEG's of different molecular weights. The pH was adjusted to the sub-samples to determine the effect of pH on the stability of the samples.

Samples 35 and 36 were evaluated for accelerated aging. The sub-samples of samples 25 and 36 were adjusted to pH using sodium citrate. Three samples were prepared for sample 35: one at pH 3.23, one at pH 3.62, and one at pH 3.91. Two samples were prepared for sample 36: one at pH 3.63 and one at pH 3.89. PH adjusted samples were also evaluated for accelerated aging. After 5 weeks of storage, sample 35 at pH 3.23 was slightly cloudy at room temperature, but remained clear at 4 ° C, 40 ° C, and 50 ° C. Sample 35 at pH 3.62 was kept clear at room temperature, 4 ° C, 40 ° C, and 50 ° C. Sample 35 at pH 3.91 was kept clear at room temperature and at 50 ° C, but was observed cloudy / opaque at 4 ° C and at 40 ° C. The results of the freeze-thaw studies were: at pH 3.23, crystals were precipitated after the second cycle, at pH 3.63 the sample was observed transparent after three cycles, and at pH 3.91, the sample was observed cloudy / opaque after each cycle. After 5 weeks of storage, sample 36 at pH 3.63 was observed transparent at room temperature, 4 ° C, 40 ° C, and 50 ° C. Sample 36 at pH 3.89 was observed to be cloudy / opaque at room temperature, nebulous at 40 ° C, and transparent at 50 ° C. The results of freezing / thawing were as follows: for pH 3.63, the sample was observed transparent after three cycles, for pH 3.89, the sample was nebulous after cycles 1 and 2, and cloudy / opaque after cycle 3. Both The molecular weight of the PEG as the pH of the sample had an effect on the physical stability of the formulation.

Claims (12)

NOVELTY OF THE INVENTION CLAIMS

1. - A composition for cleansing the skin comprising: from about 0.1 to about 5 weight percent of at least one active anti-acne ingredient; from about 1 to about 25 weight percent of at least one alcohol; from about 0.1 to about 15 weight percent of at least one solubilizer; and water.

2. The composition for cleansing the skin according to claim 1, further characterized in that the anti-acne agent is selected from the group consisting of salicylic acid, sulfur, lactic acid, glycolic acid, pyruvic acid, urea, resorcinol, N-acetylcysteine, retinoic acid, benzoyl peroxide, octopirox, triclosan, azelaic acid, phenoxyethanol, phenoxypropanol, favinoids, derivatives thereof, and combinations thereof.

3. - The composition for cleansing the skin according to claim 2, further characterized in that the anti-acne agent is selected from the group consisting of salicylic acid, benzoyl peroxide, derivatives thereof, and combinations thereof. same.

4. - The composition for cleaning the skin according to claim 1, further characterized in that the solubilizer is selected from the group consisting of propylene glycol, butylene glycol, hexylene glycol, polyethylene glycol, polysorbate-20, polysorbate-40, isoceteth-15 , Soceteth-20, isoceteth-30, sorbeth-20, sorbeth-40, PEG-40, castor oil, propylene glycol-5 ceteth 20 and combinations thereof.

5. - The composition for cleaning the skin according to claim 4, further characterized in that the solubilizer is selected from the group consisting of propylene glycol, PEG-40, castor oil, propylene glycol-5 ceteth 20, and combinations of the same.

6. The composition for cleaning the skin according to claim 5, further characterized in that the solubilizer is a polyethylene glycol containing from about 20 to about 40 repeating units of ethylene glycol.

7. - The composition for cleaning the skin according to claim 6, further characterized in that the polyethylene glycol contains 32 repeated units.

8. - The composition for cleaning the skin according to claim 7, further characterized in that the alcohol is ethanol.

9. - The composition for cleaning the skin according to claim 8, further characterized in that the anti-acne agent is salicylic acid.

10. - The composition for cleansing the skin according to claim 8, further characterized in that the amount of anti-acne agent is from about 0.5 to about 2 weight percent.

11. - The composition for cleaning the skin according to claim 9, further characterized in that the amount of ethanol is from about 10 to about 20 weight percent.

12. - The composition for cleansing the skin according to claim 10, further characterized in that the composition additionally comprises at least one emollient.