Composition, application and preparation method thereof

Abstract

The present invention relates to a composition, the use of said composition for preparing a topical preparation or cosmetic and a method for preparing said composition. The composition comprises a linear saturated dicarboxylic acid and polyaspartic acid or a derivative thereof, and the content of the polyaspartic acid or the derivative thereof is more than 0.01 weight percent, preferably more than 0.1 weight percent, more preferably 0.1 weight percent to 35 weight percent, more preferably 0.1 weight percent to 2 weight percent, further preferably 0.3 weight percent to 0.5 weight percent, based on the total weight of the composition. According to the present invention, by using a linear saturated dicarboxylic acid (e.g., azelaic acid) in combination with polyaspartic acid or a derivative thereof, the solubility of the linear saturated dicarboxylic acid (e.g., azelaic acid) in an aqueous solution can be improved, whereby it can have improved skin permeability when used, for example, in cosmetics, thereby exerting its efficacy to a greater extent.

Description

Technical Field

[0001] This invention relates to compositions comprising a straight-chain saturated dicarboxylic acid and polyaspartic acid (PASP) or a derivative thereof, such as topical compositions or cosmetic compositions. The invention also relates to the use of said compositions in the preparation of topical formulations or cosmetics, and methods for preparing said compositions. Background Technology

[0002] Linear-chain saturated dicarboxylic acids are commonly used ingredients in topical preparations and cosmetics. Azelaic acid, in particular, as a naturally occurring linear-chain saturated dicarboxylic acid, has been proven effective in treating many skin conditions, including acne, hyperpigmentation, melasma, dark spots, and pimples. Azelaic acid is also widely used in cosmetics, possessing functions such as oil control, acne treatment, brightening, moisturizing, gentle exfoliation, and skin conditioning.

[0003] However, straight-chain saturated dicarboxylic acids (such as azelaic acid) used in topical formulations or cosmetics typically have very limited solubility in aqueous solutions, especially at acidic pH levels. For example, azelaic acid has a low solubility of only 0.24 g in 100 g of water at 25°C. This solubility issue results in very limited solubility of straight-chain saturated dicarboxylic acids like azelaic acid in the formulated topical or cosmetic preparations, making it difficult for them to fully penetrate the skin and significantly limiting their efficacy.

[0004] Therefore, there is still a need to find a composition comprising straight-chain saturated dicarboxylic acids that enables straight-chain saturated dicarboxylic acids such as azelaic acid to have increased solubility in aqueous solutions, thereby allowing them to fully penetrate the skin when used, for example, in topical formulations or cosmetics. Summary of the Invention

[0005] This invention was made in view of the above-mentioned problems existing in the prior art.

[0006] In a first aspect, the present invention relates to a composition comprising: a linear saturated dicarboxylic acid, and polyaspartic acid or a derivative thereof, wherein the content of said polyaspartic acid or a derivative thereof is 0.01% by weight or more, preferably 0.1% by weight or more, more preferably 0.1% by weight to 35% by weight, even more preferably 0.1% by weight to 2% by weight, and even more preferably 0.3% by weight to 0.5% by weight, based on the total weight of said composition.

[0007] In a second aspect, the present invention relates to the use of the said composition in the preparation of topical formulations or cosmetics.

[0008] In a third aspect, the present invention relates to a method for preparing the composition, comprising: mixing the components contained in the composition.

[0009] The inventors have discovered that when linear saturated dicarboxylic acids and polyaspartic acid or its derivatives are used in combination, especially when polyaspartic acid or its derivatives are added in a specific amount, more preferably in a specific ratio, or when polyaspartic acid or its derivatives of a specific molecular weight are added, the solubility of linear saturated dicarboxylic acids (e.g., azelaic acid) in aqueous solutions, especially in acidic aqueous solutions, is improved. As a result, when used, for example, in cosmetics, it has improved skin permeability, thereby enabling it to achieve its desired therapeutic or cosmetic effects. Detailed Implementation

[0010] To make the inventive objectives, technical solutions, and beneficial technical effects of this application clearer, this application will be described in detail below. It should be noted that the various aspects, features, embodiments, and advantages described in this application can be compatible and / or combined together.

[0011] Unless otherwise specified, the technical terms used in this specification have the same meaning as commonly understood by those skilled in the art.

[0012] As used herein, the term "dicarboxylic acid" means that a dicarboxylic acid can be prepared by synthetic methods or isolated from natural sources, and can be in mixed forms or in pure or substantially pure forms. All physical forms of dicarboxylic acids, including crystalline, semi-crystalline, and amorphous forms, are within the scope of this invention.

[0013] As used herein, the term “physiologically acceptable” has the meaning known in the art and refers to compounds, materials, compositions and / or dosage forms that are suitable for contact with human and animal tissues without causing excessive toxicity, irritation, allergic reactions or other problems or complications, within a reasonable physiological judgment.

[0014] Unless otherwise stated, all quantities referred to herein are by mass, and all percentages are based on the total weight percentage of the composition.

[0015] This invention relates to compositions, their uses, and methods of preparation. The invention will be described in detail below.

[0016] Composition

[0017] In a first aspect, the present invention relates to a composition comprising a linear saturated dicarboxylic acid and polyaspartic acid or a derivative thereof.

[0018] Polyaspartic acid or its derivatives are protein-like polymers with peptide bond structures. They are easily biodegradable and have excellent properties such as safety, non-toxicity, low irritation, and environmental friendliness.

[0019] The inventors have discovered that by combining a straight-chain saturated dicarboxylic acid (e.g., azelaic acid) with polyaspartic acid or its derivatives, the solubility of the straight-chain saturated dicarboxylic acid (e.g., azelaic acid) in aqueous solutions, especially acidic aqueous solutions, can be improved, thereby enhancing its skin permeability when used, for example, in topical formulations or cosmetics, and thus maximizing its efficacy.

[0020] The content of the polyaspartic acid or its derivative may be 0.01% by weight or more, preferably 0.1% by weight or more, more preferably 0.1% by weight to 35% by weight, even more preferably 0.1% by weight to 2% by weight, and even more preferably 0.3% by weight to 0.5% by weight, based on the total weight of the composition. For example, the content of the polyaspartic acid or its derivative may be 0.01% by weight, 0.05% by weight, 0.1% by weight, 0.15% by weight, 0.2% by weight, 0.25% by weight, 0.3% by weight, 0.35% by weight, 0.4% by weight, 0.45% by weight, 0.5% by weight, 0.55% by weight, 1% by weight, 1.5% by weight, 2% by weight, 2.5% by weight, 3% by weight, 3.5% by weight, 4% by weight, 4.5% by weight, 5% by weight, 5.5% by weight, 6% by weight, 6.5% by weight, 7% by weight, 7.5% by weight, 8% by weight, 8% by weight, etc. 0.5 wt%, 9 wt%, 9.5 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, 21 wt%, 22 wt%, 23 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 29 wt%, 30 wt%, 31 wt%, 32 wt%, 33 wt%, 34 wt%, 35 wt%, or a range defined by any two thereof, based on the total weight of the composition. When the content of polyaspartic acid or its derivatives is within the above range, the solubility of straight-chain saturated dicarboxylic acids (e.g., azelaic acid) in aqueous solution can be significantly improved.

[0021] Therefore, in one embodiment, the content of the straight-chain saturated dicarboxylic acid may be 0.1 wt% to 20 wt%, preferably 0.5 wt% to 10 wt%, more preferably 1 wt% to 5 wt%, based on the total weight of the composition. For example, the content of the straight-chain saturated dicarboxylic acid may be 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.4 wt%, 0.5 wt%, 0.6 wt%, 0.7 wt%, 0.8 wt%, 0.9 wt%, 1 wt%, 2 wt%, 3 wt%, 4 wt%, 5 wt%, 6 wt%, 7 wt%, 8 wt%, 9 wt%, 10 wt%, 11 wt%, 12 wt%, 13 wt%, 14 wt%, 15 wt%, 16 wt%, 17 wt%, 18 wt%, 19 wt%, 20 wt%, or a range defined by any two thereof, based on the total weight of the composition.

[0022] In one embodiment, the weight ratio of the polyaspartic acid or its derivative to the linear saturated dicarboxylic acid can be from 0.01:1 to 20:1, particularly from 0.1:1 to 5:1, more particularly from 0.2:1 to 1:1, and especially from 0.3:1 to 0.5:1. For example, the weight ratio of the polyaspartic acid or its derivative to the linear saturated dicarboxylic acid can be 0.01:1, 0.05:1, 0.1:1, 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1, 0.5:1, 0.55:1, 0.6:1, 0.65:1, 0.7:1, 0.75:1. 1, 0.8:1, 0.85:1, 0.9:1, 0.95:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, 11:1, 12:1, 13:1, 14:1, 15:1, 16:1, 17:1, 18:1, 19:1, 20:1, or a range defined by any two of them. The inventors discovered that when the weight ratio of polyaspartic acid or its derivatives to straight-chain saturated dicarboxylic acids is within the above-mentioned range, the solubility of straight-chain saturated dicarboxylic acids (e.g., azelaic acid) in aqueous solutions, especially in acidic aqueous solutions, can be significantly improved. When the weight ratio of polyaspartic acid or its derivatives to straight-chain saturated dicarboxylic acids is 0.1:1 or higher, the solubility of straight-chain saturated dicarboxylic acids in aqueous solutions, especially in acidic aqueous solutions, is significantly improved. When the weight ratio of polyaspartic acid or its derivatives to straight-chain saturated dicarboxylic acids is 0.3:1 or higher, the solubility of straight-chain saturated dicarboxylic acids (e.g., azelaic acid) in aqueous solutions, especially in acidic aqueous solutions, can be further improved.

[0023] In one embodiment, the straight-chain saturated dicarboxylic acid may be a straight-chain saturated dicarboxylic acid having 6-10 carbon atoms (e.g., a physiologically acceptable straight-chain saturated dicarboxylic acid), preferably one or more of anthocyanic acid, azelaic acid, and sebacic acid, more preferably azelaic acid. For example, the straight-chain saturated dicarboxylic acid may be one or more of anthocyanic acid, pimelic acid, octanoic acid, azelaic acid, and sebacic acid.

[0024] In one embodiment, the polyaspartic acid derivative may be a polyaspartic acid salt, such as a physiologically acceptable polyaspartic acid salt. The polyaspartic acid salt may be selected from one or more of polyaspartic acid metal salts and polyaspartic acid ammonium salts. For example, the polyaspartic acid salt may be selected from one or more of polyaspartic acid sodium salt, polyaspartic acid potassium salt, polyaspartic acid calcium salt, polyaspartic acid magnesium salt, polyaspartic acid aluminum salt, and polyaspartic acid ammonium salt, more preferably polyaspartic acid sodium salt.

[0025] The polyaspartic acid or its derivatives can generally be represented by the following formula 1:

[0026]

[0027] In Equation 1, the sum of the number of repeating units m+n can be 2-10000, preferably 10-1000, and more preferably 200-500. For example, the sum of the number of repeating units m+n can be 2, 10, 50, 100, 150, 250, 300, 350, 400, 450, 500, 550, 600, 650, 700, 750, 800, 850, 900, 950, 1000, 2000, 3000, 4000, 5000, 6000, 8000, 10000, or a range defined by any two of these.

[0028] The ratio of m to n can be (0 to 100):(100 to 0), for example, it can be 0, 10:90, 20:80, 30:70, 40:60, 50:50, 60:40, 70:30, 80:20, 90:10, or a range defined by any two of them.

[0029] R1 and R2 can be independently selected from H, OH, and (O). p One or more of G, wherein p is 0 or 1, and G is selected from substituted or unsubstituted C1-C12 hydrocarbon groups, such as C1-C12 alkyl groups, particularly C1-C6 alkyl groups, such as methyl, ethyl, n- or iso-propyl, n-, iso-, tert- or sec-butyl, n-, iso-, tert- or sec-pentyl, or n-, iso-, tert- or sec-hexyl. In a preferred embodiment, R1 and R2 may each be H independently.

[0030] M1 and M2 can each be independently selected from one or more of H, metal cations, and ammonium cations. In a preferred embodiment, the metal is selected from one or more of sodium, potassium, calcium, magnesium, and aluminum, more preferably sodium.

[0031] In one embodiment, the weight-average molecular weight of the polyaspartic acid or its derivatives can be 1,000-100,000, particularly 2,000-50,000, for example 2,000-8,000 or 10,000-30,000, preferably 10,000-15,000. For example, the weight-average molecular weight of the polyaspartic acid or its derivatives can be 1,000, 2,000, 3,000, 4,000, 5,000, 6,000, 7,000, 8,000, 9,000, 10,000, 11,000, 12,000, 13,000, 14,000, 15,000, 16,000, 17,000, 18,000, 19,000, 20,000, 21,000, 22,000, 23,000, or 24,000. 25000, 26000, 27000, 28000, 29000, 30000, 31000, 32000, 33000, 34000, 35000, 36000, 37000, 38000, 39000, 40000, 41000, 42000, 43000, 44000, 45000, 46000, 47000, 48000, 49000, 50000, 5 1000, 52000, 53000, 54000, 55000, 56000, 57000, 58000, 59000, 60000, 61000, 62000, 63000, 64000, 65000, 66000, 67000, 68000, 69000, 70000, 71000, 72000, 73000, 74000, 75000, 76000, 77 The ranges are defined as follows: 000, 78000, 79000, 80000, 81000, 82000, 83000, 84000, 85000, 86000, 87000, 88000, 89000, 90000, 91000, 92000, 93000, 94000, 95000, 96000, 97000, 98000, 99000, 100000, or any two of these ranges. The inventors further discovered that when the weight-average molecular weight of the polyaspartic acid or its derivatives used is in the range of 10000-15000, the solubility of straight-chain saturated dicarboxylic acids (e.g., azelaic acid) in aqueous solutions can be further improved compared to corresponding polyaspartic acid or its derivatives with other molecular weight ranges, such as lower molecular weights.

[0032] In one embodiment, the polyaspartic acid or its derivatives may have a weight-average molecular weight of 10,000-15,000, and may satisfy one or more of the following characteristics (i)-(ii):

[0033] (i) The weight ratio of the polyaspartic acid or its derivative to the straight-chain saturated dicarboxylic acid is 0.1:1 to 0.5:1, preferably 0.1:1 to 0.3:1, and

[0034] (ii) The content of the polyaspartic acid or its derivative is 0.1%-0.5% by weight, more preferably 0.1%-0.3% by weight, based on the total weight of the composition.

[0035] The inventors have discovered that when the weight-average molecular weight of the polyaspartic acid or its derivatives used is in the range of 10,000-15,000 and satisfies one or more of the above characteristics (i)-(ii), the solubility of straight-chain saturated dicarboxylic acids (e.g., azelaic acid) in aqueous solution can be further significantly improved.

[0036] In one embodiment, the composition may further comprise a diol (e.g., a physiologically acceptable diol), preferably a straight-chain alkane diol, more preferably selected from straight-chain alkane diols having 2-8 carbon atoms, such as one or more selected from ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptahydrate, and octanediol, with pentanediol being even more preferred. The inventors have found that the solubility of a straight-chain saturated dicarboxylic acid (e.g., azelaic acid) in aqueous solution can be further improved when a diol compound is added to the composition comprising a straight-chain saturated dicarboxylic acid and polyaspartic acid or a derivative thereof.

[0037] In a further embodiment, when present, the weight ratio of the diol to the straight-chain saturated dicarboxylic acid can be from 0.1:1 to 10:1, particularly from 1:1 to 5:1, and more particularly from 2:1 to 5:1. For example, the weight ratio of the diol to the straight-chain saturated dicarboxylic acid can be 0.1:1, 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1, 0.5:1, 0.55:1, 0.6:1, 0.65:1, 0.7:1, 0.75:1, 0.8:1, 0.85:1, 0.9:1, 0.95:1, 1:1, 2:1, 3:1, 4:1, 5:1, 6:1, 7:1, 8:1, 9:1, 10:1, or a range defined by any two thereof.

[0038] In a further embodiment, when present, the content of the diol may be 0.1 wt% to 70 wt%, for example 1 wt% to 50 wt%, particularly 1 wt% to 10 wt%, more particularly 2 wt% to 5 wt%, based on the total weight of the composition. For example, the content of the diol may be 0.1 wt%, 0.15 wt%, 0.2 wt%, 0.25 wt%, 0.3 wt%, 0.35 wt%, 0.4 wt%, 0.45 wt%, 0.5 wt%, 0.55 wt%, 1 wt%, 1.5 wt%, 2 wt%, 2.5 wt%, 3 wt%, 3.5 wt%, 4 wt%, 4.5 wt%, 5 wt%, 5.5 wt%, 6 wt%, 6.5 wt%, 7 wt%, 7.5 wt%, 8 wt%, 8.5 wt%, 9 wt%, 9.5 wt%, 10 wt%, 20 wt%, 30 wt%, 40 wt%, 50 wt%, 60 wt%, 70 wt%, or a range defined by any two thereof, based on the total weight of the composition.

[0039] In one embodiment, the composition may be an acidic composition. For example, the pH of the acidic composition may be a physiologically acceptable pH value. For example, the pH of the composition may be 3.0-6.0, preferably 4.0-5.5, more preferably 4.5-5.0, for example, it may be 3.0, 3.5, 4.0, 4.5, 5.0, 5.5, 6.0, 6.5, or a range defined by any two thereof. The inventors have discovered that even under acidic conditions, such as pH within the above-mentioned range, the linear saturated dicarboxylic acid (e.g., azelaic acid) exhibits enhanced solubility in aqueous solutions by combining it with polyaspartic acid or a derivative thereof.

[0040] In one embodiment, the composition may further comprise a solvent. The solvent may be a physiologically acceptable solvent suitable for use in topical formulations or cosmetics. The solvent may be water or an organic solvent (including solvents miscible with water), preferably water. The solvent content may be 10-99% by weight, based on the total weight of the composition. For example, the solvent (e.g., water) content may be 10% by weight, 15% by weight, 20% by weight, 25% by weight, 30% by weight, 35% by weight, 40% by weight, 45% by weight, 50% by weight, 55% by weight, 60% by weight, 65% by weight, 70% by weight, 75% by weight, 80% by weight, 85% by weight, 90% by weight, 95% by weight, 98% by weight, 99% by weight, or a range defined by any two thereof, based on the total weight of the composition. The solvent described herein does not include or differs from the aforementioned diols.

[0041] In one embodiment, the composition may further comprise one or more components selected from: surfactants, such as cationic surfactants, anionic surfactants, amphoteric surfactants and / or nonionic surfactants; thickeners, such as polysaccharide thickeners, silicone elastomers and / or acrylate polymers; oils and fats; inorganic salts; pH adjusters (also known as acid-base regulators); and anti-inflammatory ingredients. The components may be appropriately selected depending on the intended use and are not particularly limited thereto. The amounts of each component are not particularly limited and can be selected independently and appropriately according to the intended use. For example, the amounts of each component can be 0.05-10% by weight, such as 0.05% by weight, 0.1% by weight, 0.2% by weight, 0.3% by weight, 0.4% by weight, 0.5% by weight, 1% by weight, 1.5% by weight, 2% by weight, 2.5% by weight, 3% by weight, 3.5% by weight, 4% by weight, 4.5% by weight, 5% by weight, 5.5% by weight, 6% by weight, 6.5% by weight, 7% by weight, 7.5% by weight, 8% by weight, 8.5% by weight, 9% by weight, 9.5% by weight, 10% by weight, or a range defined by any two thereof, based on the total weight of the composition.

[0042] Examples of suitable surfactants include, but are not limited to: polysorbate-20, polysorbate-40, polysorbate-60, lecithin, hydrogenated lecithin, stearyl alcohol polyether-20, PEG-100 stearate, PEG-40 hydrogenated castor oil, polyglycerol-10 laurate, polyglycerol-10 oleate, polyglycerol-10 stearate, polyglycerol-5 oleate, polyglycerol-6 stearate, PPG-6-decyltetradecyl alcohol polyether-30, PPG-26-butanol polyether-26, etc.

[0043] Examples of suitable thickeners include, but are not limited to: xanthan gum, guar gum, carrageenan, poloxamer, carbomer, sodium hyaluronate, acrylates / C10-30 alkanol acrylate crosspolymers, etc.

[0044] Suitable oils and fats include, but are not limited to: silicone oils, esters, vegetable oils, synthetic oils (including volatile and non-volatile oils), mineral oils, petrolatum, etc.

[0045] Examples of suitable inorganic salts include, but are not limited to: sodium chloride, magnesium sulfate, and zinc chloride.

[0046] Examples of suitable pH adjusters include, but are not limited to: sodium hydroxide, potassium hydroxide, and aqueous solutions of hydrogen chloride.

[0047] Examples of suitable anti-inflammatory ingredients include, but are not limited to: salicylic acid and its physiologically acceptable salts, dipotassium glycyrrhizate, 4-tert-butylcyclohexanol, witch hazel extract, bisabolol, olive leaf extract, etc.

[0048] In one embodiment, the composition may further comprise a chemical stripping agent, examples of suitable chemical stripping agents including glycolic acid, citric acid, lactic acid, malic acid, pyruvic acid, tartaric acid, salicylic acid, lactobionic acid, maltodextrin, gluconolactone, etc.

[0049] In one embodiment, the composition may further comprise other additives, provided that these additives are physically and chemically compatible with the components in the composition, dissolve in the composition, and do not impair the therapeutic or cosmetic properties of the composition. Examples of such other additives include, but are not limited to, moisturizing compounds, vitamins, antioxidants, and film-forming polymers. Examples of suitable moisturizing compounds include, but are not limited to, betaine, N-2-hydroxyethyl urea, polyol ethers and esters, low molecular weight polyethylene glycol, lactates, sugars, methyl gluconate, sodium pyrrolidone carboxylate, sodium hyaluronate, panthenol, and hyaluronic acid. Examples of suitable vitamins include, but are not limited to, tocopherol phosphate, vitamin B2 and its derivatives, vitamin B3 and its derivatives such as niacinamide, and vitamin C and its derivatives. Examples of suitable antioxidants include, but are not limited to, green tea extract, grape seed extract, flavonoids, inositol and its derivatives, glutathione, cysteine ​​and its derivatives, proline, and carnitine and its derivatives.

[0050] In one embodiment, the composition may further comprise other ingredients as needed, including but not limited to: skin penetration enhancers, chelating agents, preservatives, colorants, inorganic salts, pH adjusters, fragrances, etc. Examples of suitable skin penetration enhancers include, but are not limited to: tetrahydropiperine, isosorbide dimethyl ether, hexanediol, and butylene glycol. Examples of suitable chelating agents include, but are not limited to: ethylenediaminetetraacetic acid (EDTA), ethylene glycol diethyl ether diaminetetraacetic acid (EDTA), and their physiologically acceptable salts.

[0051] In one embodiment, the composition may be a topical composition, particularly for treating skin disorders such as pigmentation, melasma, dark spots, acne, or pimples; for increasing the penetration of active ingredients; for promoting epidermal exfoliation; for brightening skin tone and reducing hyperpigmentation; for controlling oil production; for enhancing skin barrier function; or for making skin smooth and soft.

[0052] In one embodiment, the composition may be a cosmetic composition, particularly a brightening composition, a spot-removing composition, an oil-controlling composition, an exfoliating composition, or an acne-removing composition.

[0053] The inventors have discovered that when linear saturated dicarboxylic acids, such as azelaic acid, and polyaspartic acid (PASP) or their derivatives are used in combination in topical and cosmetic compositions, the solubility of linear saturated dicarboxylic acids, such as azelaic acid, in the composition is significantly improved, thereby significantly enhancing its skin permeability when applied to the skin, thus achieving the desired therapeutic or cosmetic effects.

[0054] use

[0055] In a second aspect, the present invention relates to the use of compositions according to the first aspect of the invention in the preparation of topical formulations or cosmetics.

[0056] The compositions according to the first aspect of the invention are particularly suitable for use in the preparation of topical formulations or cosmetics, especially cosmetics. When the compositions according to the first aspect of the invention are used in topical and cosmetic compositions, the skin permeability of straight-chain saturated dicarboxylic acids, such as azelaic acid, is significantly improved when the topical and cosmetic compositions are applied to the skin, thereby achieving the desired therapeutic or cosmetic effects.

[0057] However, the use of the composition according to the first aspect of the invention is not particularly limited, for example, the composition can be used for other applications requiring improved solubility of straight-chain saturated dicarboxylic acids (e.g., azelaic acid) in water or skin permeability.

[0058] Preparation method

[0059] In a third aspect, the present invention relates to a method for preparing a composition according to a first aspect of the invention, comprising: mixing the components contained in the composition.

[0060] There are no particular restrictions on the order in which the components are mixed. For example, the components can be mixed together or sequentially; all components can be added and dissolved in the total amount of solvent at once or in batches according to a certain order; or some components can be added and dissolved in a portion of solvent or a solvent at once or in batches according to a certain order, while the remaining components can be added and dissolved in another portion of solvent at once or in batches according to a certain order, and then the resulting solutions can be combined.

[0061] The components contained in the composition are as described in the section on the composition above, and will not be repeated here.

[0062] Example

[0063] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0064] I. Source of Raw Materials

[0065] The sources of the raw materials involved in the examples are shown in Table 1 below.

[0066] Table 1: Sources of each raw material

[0067]

[0068] II. Testing Methods

[0069] Solubility test

[0070] Transfer 200 μL of the composition containing azelaic acid into a 96-well plate and measure turbidity. Measure the absorbance of the sample at 700 nm using a microplate reader (INFINITE E PLEX, TECAN, Austria). Higher absorbance indicates higher turbidity, meaning more azelaic acid remains undissolved.

[0071] Skin permeability test

[0072] The composition sample containing azelaic acid was placed in a 4°C incubator and allowed to stand for one week before being removed. Transdermal absorption experiments were performed using a Franz diffusion cell (Teledyne Technologies). A Strat-M membrane from a skin model was sandwiched between the diffusion cell cap and the diffusion cell. The inner surface of the membrane was immersed in the receiving solution (composed of 0.1% Tween 20, 10% ethanol, and 89.9% PBS buffer solution), and the receiving solution was magnetically stirred at a constant temperature of 25°C. 35 mg of the composition sample containing azelaic acid was added to the membrane surface and evenly spread using a syringe core. After 8 hours, the receiving solution was collected for HPLC quantitative analysis of azelaic acid.

[0073] III. Dissolution Experiment of Azelaic Acid

[0074] According to the composition shown in Table 2-4 below, azelaic acid powder, sodium polyaspartate, and sodium hydroxide were added to water and magnetically stirred at room temperature for 24 hours. Then, ultrasonic dispersion was performed until the azelaic acid particles were uniformly dispersed to prepare composition AS. The solubility of each composition was tested according to the solubility test method described above to determine the solubility of azelaic acid within it. The solubility test results of azelaic acid in each composition are also shown in Table 2-4 below.

[0075] Table 2

[0076]

[0077] As shown in Table 2 above, the solubility of azelaic acid in aqueous solution is improved in composition BG with added sodium polyaspartate compared to composition A without sodium polyaspartate. The solubility of azelaic acid in aqueous solution increases with the increase of the weight ratio of sodium polyaspartate to azelaic acid, especially when the weight ratio is 0.1:1 or higher, where the improvement is particularly significant. The solubility is further improved when the weight ratio is 0.3:1 or higher. The absorbance of composition G is comparable to that of composition H, indicating that all the azelaic acid in it is dissolved.

[0078] Table 3

[0079]

[0080] As shown in Table 3 above, both polyaspartic acid sodium A and polyaspartic acid sodium B with different molecular weights can solubilize azelaic acid. Furthermore, polyaspartic acid sodium B with a weight-average molecular weight of 13,000 can further improve the solubility of azelaic acid in aqueous solution compared to polyaspartic acid sodium A with a weight-average molecular weight of 5,000. This solubilizing effect of polyaspartic acid sodium on azelaic acid is particularly significant when polyaspartic acid sodium and azelaic acid are combined in ratios of 0.1:1 and 0.3:1.

[0081] Table 4

[0082]

[0083]

[0084] As shown in Table 4 above, when pentylene glycol is added, the solubility of azelaic acid in aqueous solution increases with the increase of the amount of pentylene glycol added. That is, the addition of pentylene glycol further improves the solubility of azelaic acid in aqueous solution.

[0085] IV. Skin permeability test of azelaic acid

[0086] Following the composition shown in Table 5 below, azelaic acid powder, sodium polyaspartate A, solubilizer polyethylene glycol-40 hydrogenated castor oil (CREMOPHOR RH-40), and humectant 1,3-butanediol were added to water, followed by the addition of sodium hydroxide to adjust the pH of the system to 4.5. The mixture was then stirred thoroughly at 50°C until completely dissolved to prepare the compositions of Example 1 and Comparative Example 1. Skin permeability tests were performed on each composition to determine the skin permeability of the azelaic acid contained therein. The results of the skin permeability tests for azelaic acid in each composition are also shown in Table 5 below.

[0087] Table 5

[0088]

[0089] Therefore, the above data proves that the combination of sodium polyaspartate and azelaic acid significantly improves the permeability of azelaic acid in the skin, thereby helping to enhance its efficacy.

[0090] The above description is merely an exemplary embodiment of the present invention. It should be noted that those skilled in the art can make improvements to the present invention without departing from the inventive concept, and all such improvements fall within the scope of protection of the present invention.

Claims

1. A composition comprising: Straight-chain saturated dicarboxylic acids, and Polyaspartic acid or its derivatives, wherein the content of said polyaspartic acid or its derivatives is 0.01% by weight or more, preferably 0.1% by weight or more, more preferably 0.1% by weight to 35% by weight, even more preferably 0.1% by weight to 2% by weight, and even more preferably 0.3% by weight to 0.5% by weight, based on the total weight of said composition.

2. The composition of claim 1, wherein the weight ratio of the polyaspartic acid or its derivative to the straight-chain saturated dicarboxylic acid is 0.01:1 to 20:1, particularly 0.1:1 to 5:1, more particularly 0.2:1 to 1:1, and especially 0.3:1 to 0.5:

1.

3. The composition according to claim 1 or 2, wherein the straight-chain saturated dicarboxylic acid is a straight-chain saturated dicarboxylic acid having 6-10 carbon atoms, preferably one or more of azelaic acid, azelaic acid and sebacic acid, more preferably azelaic acid.

4. The composition of claim 1 or 2, wherein the polyaspartic acid derivative is a polyaspartic acid salt, such as a physiologically acceptable polyaspartic acid salt, preferably selected from one or more of sodium polyaspartic acid, potassium polyaspartic acid, calcium polyaspartic acid, magnesium polyaspartic acid, aluminum polyaspartic acid, and ammonium polyaspartic acid, more preferably sodium polyaspartic acid.

5. The composition of claim 1 or 2, wherein the polyaspartic acid or a derivative thereof is represented by formula 1: The sum of the number of repeating units m+n is 2-10000, preferably 10-1000, and more preferably 200-500; R1 and R2 are each independently selected from H, OH, and (O). p One or more of G, wherein p is 0 or 1, G is selected from substituted or unsubstituted C1-C12 hydrocarbon groups, such as C1-C12 alkyl groups, preferably R1 and R2 are each independently H; and M1 and M2 are each independently selected from one or more of H, metal cations and ammonium cations, preferably the metal is selected from one or more of sodium, potassium, calcium, magnesium and aluminum.

6. The composition of claim 1 or 2, wherein the polyaspartic acid or its derivative has a weight-average molecular weight of 1,000-100,000, particularly 2,000-50,000, for example 2,000-8,000 or 10,000-30,000, preferably 10,000-15,000.

7. The composition of claim 1 or 2, wherein the content of the straight-chain saturated dicarboxylic acid is 0.1%-20% by weight, preferably 0.5%-10% by weight, more preferably 1%-5% by weight, based on the total weight of the composition.

8. The composition of claim 1 or 2, wherein the polyaspartic acid or its derivative has a weight-average molecular weight of 10,000-15,000 and satisfies one or more of the following characteristics (i)-(ii): (i) The weight ratio of the polyaspartic acid or its derivative to the straight-chain saturated dicarboxylic acid is 0.1:1 to 0.5:1, preferably 0.1:1 to 0.3:1, and (ii) The content of the polyaspartic acid or its derivative is 0.1%-0.5% by weight, more preferably 0.1%-0.3% by weight, based on the total weight of the composition.

9. The composition of claim 1 or 2, wherein the composition further comprises a diol, preferably a straight-chain saturated diol, more preferably selected from straight-chain saturated diols having 2-8 carbon atoms, and even more preferably selected from one or more of propylene glycol, butanediol, pentanediol, hexanediol, and heptanediol.

10. The composition of claim 9, wherein the weight ratio of the diol to the straight-chain saturated dicarboxylic acid is 0.1:1 to 10:1, particularly 1:1 to 5:1, and more particularly 2:1 to 5:

1.

11. The composition of claim 9, wherein the content of the diol is 0.1 wt% to 70 wt%, for example 1 wt% to 50 wt%, particularly 1 wt% to 10 wt%, more particularly 2 wt% to 5 wt%, based on the total weight of the composition.

12. The composition of claim 1 or 2, wherein the pH of the composition is 3.0-6.0, preferably 4.0-5.5, more preferably 4.5-5.

0.

13. The composition of claim 1 or 2, wherein the composition further comprises a solvent, particularly water.

14. The composition of claim 1 or 2, wherein the composition is a topical composition, particularly for treating skin disorders such as pigmentation, melasma, freckles, acne, or pimples; for increasing the penetration of active ingredients; for promoting epidermal exfoliation; for brightening skin tone and reducing hyperpigmentation; for controlling oil production; for enhancing skin barrier function; or for making skin smooth and soft.

15. The composition of claim 1 or 2, wherein the composition is a cosmetic composition, particularly a brightening composition, a spot-removing composition, an oil-controlling composition, an exfoliating composition, or an acne-removing composition.

16. The composition of claim 1 or 2, wherein the composition further comprises one or more ingredients selected from: surfactants, such as cationic surfactants, anionic surfactants, amphoteric surfactants and / or nonionic surfactants; thickeners, such as polysaccharide thickeners, silicone elastomers and / or acrylate polymers; oils; inorganic salts; pH adjusters; and anti-inflammatory components.

17. Use of the composition according to any one of claims 1-16 for the preparation of topical formulations or cosmetics.

18. A method for preparing the composition according to any one of claims 1-16, comprising: The components contained in the composition are mixed.

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