Double layer cosmetic composition containing high concentration azelaic acid

Abstract

The present invention provides a cosmetic composition that enhances the skin penetration of azelaic acid and increases the skin acne improvement effect by improving the skin whitening phenomenon that occurs when azelaic acid is applied to the skin, by using a double-layer formulation utilizing an oil component when azelaic acid or a pharmaceutically acceptable salt thereof, which is highly effective for skin troubles such as acne, is used at a high concentration of 10% by weight or more.

Description

Technology Field

[0001] The present invention relates to a double-layer cosmetic composition comprising a high concentration of azelaic acid or a pharmaceutically acceptable salt thereof in an amount of 10 weight% or more. Background Technology

[0002] Azelaic acid is a naturally occurring dicarboxylic acid known as a useful active ingredient for treating skin diseases through its antibacterial and anti-inflammatory effects, as well as its inhibitory effect on keratinization. In particular, it is widely used in the treatment of acne vulgaris, rosacea, and hyperpigmentation. However, azelaic acid is chemically unstable when used at high concentrations of 10% by weight or more and may decompose or discolor due to temperature, pH, ultraviolet rays, or oxidizing environments. Additionally, physically, it can easily crystallize or be non-uniform in a dispersed state, and when applied to the skin at high concentrations in an aqueous solution, it acts on the stratum corneum to leave white marks (whitening phenomenon), which hinders the stability of the formulation and the continuous delivery of the active ingredient.

[0003] Due to these issues, it is currently difficult to ensure the storage stability and maintain the quality of preparations containing azelaic acid during the shelf life. To address this, various stabilization technologies have been attempted.

[0004] For example, although various technologies such as solid dispersion, nanoparticle formation, complex formation, and encapsulation have been applied, there are still limitations in completely suppressing the degradation and physical instability of azelaic acid. In particular, the issue of the ingredient becoming unstable due to changes in pH or temperature conditions during use acts as a major factor hindering the efficacy and safety of the product.

[0005] Therefore, there is an urgent need to develop technology that improves the chemical and physical stability of azelaic acid to maintain the quality of the formulation and ensures the active ingredient remains stable even during long-term storage and use.

[0006] As prior art, Korean Registered Patent No. 10-0861978 describes a cosmetic composition for treating acne using azelaic acid, comprising: (a) a lipid dissolving part comprising 1.0 to 5.0 parts by weight of a bio-lipid selected from the group consisting of phytosphingosine, ceramide, phospholipid, tetraacetylphytosphingosine, and acetylphytosphingosine, and 5.0 to 50.0 parts by weight of a polyhydric alcohol; and (b) an azelaic acid dissolving part comprising 0.1 to 20.0 parts by weight of azelaic acid and 10.0 to 70.0 parts by weight of a volatile alcohol. A composition comprising (c) an aqueous portion of a plant extract selected from the group consisting of 1.0 to 10.0 parts by weight of purified water, 0.1 to 2.0 parts by weight of lactic acid, and 0.1 to 10.0 parts by weight of a plant extract selected from the group consisting of grapefruit peel extract, purslane extract, aloe extract, licorice extract, hollyhock extract, and kava kava extract is described; and Korean Published Patent No. 2023-0051275 describes a skin care formulation composition comprising azelaic acid, wherein the skin care formulation further comprises a first booster composition comprising a first active booster component, and the skin care formulation further comprises a second booster composition comprising at least one second active booster component, wherein the skin care formulation is a water-based emulsion stable for at least 3 months, and a method for forming the skin care formulation is described as a skin care formulation formed by combining an anti-acne booster composition, a first booster composition, a second booster composition, and an aqueous base composition; and Japanese Published Patent Korean Patent Publication No. 2023-540049 describes a skin care formulation containing azelaic acid as an anti-acne efficacy promoter composition, and Korean Patent Publication No. 2011-0133198 describes an aqueous acne treatment composition characterized by containing 15-25% by weight of azelaic acid, 30-50% by weight of polyalcohol, 10-20% by weight of surfactant, and 20-45% by weight of water.

[0007] However, the aforementioned prior art differs from the composition and effects of the present invention. The inventors conducted research to increase the efficacy of azelaic acid by stabilizing a high concentration of 10% by weight or more of azelaic acid and applying it to the skin. Through this, they confirmed that when azelaic acid is used to create a double layer of oil and water phases, the stability of azelaic acid increases, and when applied to the skin, the whitening phenomenon disappears and the acne improvement effect increases, thereby completing the present invention. Prior art literature

[0008] (Patent-0001) Cosmetic composition for treating acne using azelaic acid and method for preparing the same, Korean Registered Patent No. 10-0861978 (Registration Date: September 30, 2008) (Patent-0002) Korean Published Patent No. 2023-0051275, Skin care composition containing azelaic acid (Publication Date: April 17, 2023) (Patent-0003) Japanese Published Patent No. 2023-540049, Skin care composition containing azelaic acid and method for preparing a skin care composition (Publication Date: September 21, 2023) (Patent-0004) Korean Published Patent No. 2011-0133198, Composition for treating acne and cosmetic composition for improving acne using the same (Publication Date: December 12, 2011) The problem to be solved

[0009] According to the cosmetic composition of the present invention, the stability of the formulation is increased by applying a high concentration of azelaic acid or a pharmaceutically acceptable salt thereof at a concentration of 10% by weight or more to an oil-water and aqueous dual-layer formulation, and the acne-improving effect of azelaic acid is increased by improving the whitening phenomenon of azelaic acid caused by the high concentration when applied to the skin. means of solving the problem

[0010] To achieve the above objective, the present invention provides a cosmetic composition having a double-layer formulation comprising an oil phase and a water phase, wherein the oil phase comprises one or more types of ester oils, vegetable oils, silicone oils, etc., and the water phase comprises water, azelaic acid, a pH adjuster, a preservative, and other solvents.

[0011] The present invention provides a cosmetic composition of an oil / water dual-layer formulation comprising one or more of the above vegetable oils, ester oils, silicone oils, etc.

[0012] The present invention relates to an oil / water double layer composition wherein the vegetable oil is one or more selected from vegetable oils such as Centella oil, Argan oil, Jojoba oil, Rosehip oil, Sunflower seed oil, Olive oil, Sweet Almond oil, Grapeseed oil, Macadamia nut oil, Avocado oil, Coconut oil, Sunflower oil, Canola oil, Bamboo seed oil, Hemp seed oil, Broccoli seed oil, Camellia oil, Pequi nut oil, Black currant seed oil, Borage seed oil, and Chia seed oil. Provides

[0013] The present invention relates to the ester-based oil comprising isopropyl myristate, isopropyl palmitate, ethylhexyl palmitate, dicaprylyl carbonate, dicaprylyl ether, caprylic / capric triglyceride, butylene glycol dicaprylate / dicaprate, cetyl ethylhexanoate, isopropyl pimaprilate, C12-15 alkyl benzoate, triethylhexanoin, and diisostearyl malate. The present invention provides an oil-water-water bilayer composition comprising one or more synthetic oils selected from isostearyl isostearate, hexyl laurate, myristyl lactate, etc.

[0014] In addition, the present invention provides a cosmetic composition of an oil / water dual-layer formulation in which the oil phase component is one or more selected from the group consisting of vinyl dimethicone / methicone silsesquioxane crosspolymer, polysilicon-11, polysilicon-13, diphenyl dimethicone / vinyl diphenyl dimethicone / silsesquioxane crosspolymer, dimethicone / vinyl dimethicone crosspolymer, dimethicone / phenyl vinyl dimethicone crosspolymer, and polymethylsilsesquioxane.

[0015] The present invention provides a cosmetic composition in an oil-water-water dual-layer formulation containing the azelaic acid or a pharmaceutically acceptable salt thereof in a high concentration of 10% to 15% by weight. The present invention provides a cosmetic composition using 10% by weight of azelaic acid.

[0016] In the present invention, the pH regulator of the aqueous phase may be one or more selected from the alkali group, such as sodium hydroxide, potassium hydroxide, arginine, and triethanolamine, which are mild alkaline pH regulators of the amino acid series.

[0017] In the present invention, the preservative in the aqueous portion may be one or more preservatives such as phenoxyethanol, ethylhexylglycerin, and hexanediol.

[0018] In addition, the present invention provides a cosmetic composition of an oil-water-dual-layer formulation in which the content of the aqueous phase is 75% by weight or more and 90% by weight or less with respect to the total weight of the cosmetic composition of the oil-water-dual-layer formulation. In addition, the present invention provides a cosmetic composition of an oil-water-dual-layer formulation in which the content of the azelaic acid or a pharmaceutically acceptable salt thereof is 10% by weight or more with respect to the total weight of the cosmetic composition. Effects of the invention

[0019] The present invention improves the skin penetration of azelaic acid and increases the skin acne improvement effect by improving the skin whitening phenomenon that occurs when azelaic acid in an aqueous solution is applied to the skin, by using a double-layer formulation utilizing an oil component when azelaic acid or a pharmaceutically acceptable salt thereof, which is highly effective for skin troubles such as acne, is used at a high concentration of 10% by weight or more. Brief explanation of the drawing

[0020] Figure 1 is a figure showing the whitening phenomenon occurring on the skin of the face and hands when using 10 wt% high concentration azelaic acid. Specific details for implementing the invention

[0021] Hereinafter, preferred embodiments of the present invention will be described in detail so that a person skilled in the art to which the present invention pertains can easily practice the present invention.

[0022] The cosmetic composition of an oil-water-oil bilayer formulation referred to in the present invention means a bilayer cosmetic composition separated into a water phase and an oil phase. The cosmetic composition of a bilayer formulation according to the present invention comprises an oil phase and a water phase, wherein the oil phase comprises one or more of the natural oil, ester oil, and silicone oil, and the water phase may comprise water, azelaic acid or a pharmaceutically acceptable salt thereof, other solvents, and pH adjusters.

[0023] In addition, the cosmetic composition may also contain trilaureth-4 phosphate, polyglyceryl-3 diisostearate, etc. as surfactants in an amount of 0.01 weight% or less.

[0024] Hereinafter, the composition of the cosmetic composition of the oil-water-dual-layer formulation of the present invention will be examined in more detail.

[0025] The oil phase of the double-layer formulation composition of the present invention may include one or more types of natural vegetable oils, ester oils, and silicone oils. Specifically, one or more types selected from the oil groups described above may be used, and preferably, Centella asiatica oil, which is a vegetable oil, may be used as the main component.

[0026] The content of the above oil phase may be 10% by weight or more and 30% by weight or less with respect to the total weight of the cosmetic composition of the oil-water dual-layer formulation, and preferably 10% by weight or more and 15% by weight or less. If the content of the above oil phase is less than 10% by weight, the content of the external phase is too low to stably form the formulation, and if it exceeds 30% by weight, it is undesirable because the formulation stability and usability are reduced.

[0027] The aqueous phase of the oil-water-water dual-layer formulation cosmetic composition of the present invention may comprise water, azelaic acid or a pharmaceutically acceptable salt thereof and a pH adjuster.

[0028] The above-mentioned azelaic acid includes azelaic acid derivatives in which various molecules are organically chemically attached to the carbon chains of azelaic acid so as not to easily decompose in the raw material state or in a dissolved or dispersed state, while maintaining the level of activity typically exhibited by the original azelaic acid when applied to the skin.

[0029] The above aqueous phase may include a pH adjuster to stabilize the azelaic acid or a pharmaceutically acceptable salt thereof, and preferably may include a basic pH adjuster. The pH adjuster may be one or more selected from the alkali group, such as sodium hydroxide, potassium hydroxide, arginine, and triethanolamine, which are mild alkaline pH adjusters of the amino acid series.

[0030] The aqueous phase of the cosmetic composition of the oil-water-dual-layer formulation of the present invention may comprise 70% by weight or more and 90% by weight or less of water with respect to the total weight of the cosmetic composition of the dual-layer formulation, and preferably may comprise 85% by weight or more and 90% by weight or less of water. If the water content is less than 70% by weight, the content of the internal phase is too low and the moisture sensation is insufficient, and it is difficult to sufficiently dissolve azelaic acid or a pharmaceutically acceptable salt thereof; if it exceeds 90% by weight, it is undesirable because it is difficult to stably form the formulation.

[0031] Accordingly, the present invention relates to a cosmetic composition of a double-layer formulation of azelaic acid that improves the whitening phenomenon of azelaic acid and increases the acne-improving effect, characterized in that the oil phase containing oil is in a weight ratio of 10 to 30, and the aqueous phase containing azelaic acid or a pharmaceutically acceptable salt thereof and a pH adjuster is in a weight ratio of 70 to 90.

[0032] The cosmetic composition of the double-layer formulation of the present invention may further include other additives. More specifically, one or more selected from the group consisting of polyols such as glycerin, propanediol, 1,2-hexanediol, butylene glycol, and caprylyl glycol, sodium chloride, disodium EDTA, water-soluble functional ingredients (arbutin, niacinamide, adenosine, caffeine, etc.), emollients such as oleyl alcohol, anti-discoloration agents such as benzophenone-9, thickeners such as carboxyvinyl polymer or cellulose gum, various emollients such as ethanol and ethylhexylglycerin as solvents, moisturizers, fragrances, and preservatives may be used, but are not limited thereto.

[0033] < Preparation Example 1 : 10 weight% High concentration Azelaic Mountain Includes double layer serum Manufacturing>

[0034] The above double-layer formulation example containing 10 wt% azelaic acid and Centella asiatica oil was prepared according to a conventional method with the composition of Table 1.

[0035] Ingredients Content (weight%) Azelaic acid, Triethanolamine (pH regulator), Oleyl alcohol, Ethanol, Benzophenone-9, Carboxylvinyl polymer, Cellulose gum, Centella asiatica oil (vegetable oil), Phenoxyethanol, Purified water 10.02.01.53.22.01.03.515.0 Trace Remaining Amount total 100

[0037] <Preparation Example 2: Preparation of a double-layer serum containing 10 wt% high-concentration azelaic acid>

[0038] The above double-layer formulation example containing 10 wt% azelaic acid and ester oil was prepared according to a conventional method with the composition of Table 2.

[0039] Ingredients Content (weight%) Azelaic acid, Triethanolamine (pH regulator), Oleyl alcohol, Ethanol, Benzophenone-9 Carboxylvinyl Polymer, Cellulose Gum, Cetyl Ethylhexanoate (Ester Oil), Phenoxyethanol, Purified Water 10.02.01.53.22.01.03.515.0 Trace Remaining Amount total 100

[0040] < Test example 1 : 10 weight% High concentration Azelaic Mountain inclusive double layer serum's Acne improvement effect>

[0041] To observe the acne-improving effect of the double-layer formulation prepared in the above preparation example, a test was conducted as follows. First, a standard formulation serum containing 10% by weight of azelaic acid was prepared as a control group and a comparison group, and double-layer formulation serums were prepared for Test Group 1 (Preparation Example 1) and Test Group 2 (Preparation Example 2). A clinical test using these was conducted as follows.

[0042] ① Subjects: Clinical trial conducted on 40 subjects (20 women, 20 men) aged around 20 years with acne or erythema, divided into Test Group 1 (5 women, 5 men), Test Group 2 (5 women, 5 men), Control Group (5 women, 5 men), and Comparison Group (5 women, 5 men) according to the preparation of the present invention.

[0043] ② Test group: Dual-layer formulation serum containing 10 wt% azelaic acid (Preparation Example 1, Preparation Example 2)

[0044] ③ Control group: Double-layer serum not containing azelaic acid

[0045] ④ Comparison group: Serum containing 10% by weight of azelaic acid

[0046] ⑤ Evaluation method: Ten subjects were each instructed to use Test Group 1, Test Group 2, Control Group, and Comparison Group twice a day after washing their face, and the degree of acne improvement was evaluated over 4 weeks.

[0047] ⑥ Evaluation Item: - Change in the number of inflammatory / non-inflammatory acne lesions

[0048] - Presence or absence of whitening of the skin after using azelaic acid

[0049] - Degree of improvement in pigmentation

[0050] The clinical trial results (results after 4 weeks of clinical trial) are shown in Table 3 below.

[0051] Evaluation criteria control group Comparison group Test group 1 (Preparation Example 1) Test group 2 (Preparation Example 2) Improvement of acne lesions doesn't exist excellence Very excellent Very excellent whitening phenomenon Not found (0% occurrence) Occurrence (100% occurrence) Not found (0% occurrence) Not found (0% occurrence) skin tone improvement doesn't exist excellence Very excellent Very excellent Presence or absence of skin irritation doesn't exist doesn't exist doesn't exist doesn't exist

[0053] In summary, the above results demonstrate that when using azelaic acid or its pharmaceutically acceptable salts, formulating the aqueous phase as a double layer using an oil-based upper layer prevents whitening, thereby increasing stability and efficacy in improving acne lesions.

Claims

Claim 1 A cosmetic composition comprising an oil phase and an aqueous phase containing 10% by weight of azelaic acid or a pharmaceutically acceptable salt, wherein the composition comprises: (a) an oil phase comprising Centella asiatica oil or cetyl ethylhexanoate oil in a weight ratio of 10 to 30; and (b) an aqueous phase comprising azelaic acid or a pharmaceutically acceptable salt thereof and a pH adjuster in a weight ratio of 70 to 90; characterized in that it improves the whitening phenomenon of azelaic acid and increases the acne-improving effect. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 delete Claim 6 A cosmetic composition of an azelaic acid double-layer formulation according to claim 1, characterized in that the pH adjuster of the aqueous phase comprises one or more selected from sodium hydroxide, potassium hydroxide, arginine, and triethanolamine. Claim 7 delete Claim 8 delete Claim 9 delete Claim 10 A cosmetic composition of an azelaic acid double-layer formulation characterized by being composed of the ingredients in the table below. Claim 11 A cosmetic composition of an azelaic acid double-layer formulation characterized by being composed of the ingredients in the table below.

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