Crystallization inhibitor for skin cosmetics and yellowing inhibitor for skin cosmetics

Abstract

To provide a component that inhibits crystallization caused by nicotinamide, and a component that inhibits yellowing of cosmetics under light irradiation, such as ultraviolet rays or LED light, caused by nicotinamide.SOLUTION: The present invention provides a crystallization inhibitor for skin cosmetics derived from a component (A) containing the following components (B) and (C) as active ingredients, or a yellowing inhibitor for skin cosmetics derived from (A) containing (B) and (C) as active ingredients. Preferably, the blending ratios of (A), (B), and (C) are as follows: (B) / (A) is 0.01 or more, (C) / (A) is 0.05 or more, and ((B)+(C)) / (A) is 0.1 or more. (A) Nicotinamide. (B) Pantothenyl alcohol. (C) Phenoxyethanol.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a technique for suppressing crystal precipitation and yellowing and deterioration over time that are derived from nicotinamide by combining nicotinamide with pantothenyl alcohol and phenoxyethanol. [Background technology]

[0002] Nicotinamide is a substance that has various beauty effects, and is often used in cosmetics or quasi-drugs for skin care. In addition, in order to fully exert its beauty effects, a method of enhancing the effect by blending nicotinamide in cosmetics at a high concentration has been studied. Nicotinamide is a water-soluble substance and a relatively stable compound, but it has become clear in recent years that blending it in cosmetics at a high concentration causes the cosmetics attached to the container to dry over time and the moisture to evaporate, resulting in white crystal precipitation due to nicotinamide, which not only reduces the quality of the cosmetics, but also causes unpleasant gritty sensations to the touch and undesirable appearance. In addition, it has become clear that when nicotinamide is blended in cosmetics at a high concentration, depending on the storage conditions of the cosmetics, the entire cosmetics may yellow or smell bad due to deterioration due to temperature and light, or due to the effects of long-term storage.

[0003] In view of this background, several studies have been made to suppress the precipitation of nicotinamide crystals. For example, known examples include a combination of nicotinamide and tranexamic acid, and further combination of D-pantothenyl alcohol and a polyhydric alcohol (see, for example, Patent Document 1), a combination of nicotinamide and tranexamic acid, and further combination of mucopolysaccharide and an amphiphilic polymer (see, for example, Patent Document 2), and a combination of nicotinamide and tranexamic acid, and further combination of pyrrolidone carboxylic acid (see, for example, Patent Document 3).

[0004] It is also known that cosmetics containing nicotinamide turn yellow over time due to heat or light exposure. As a method for suppressing this, for example, a case has been reported in which discoloration due to the combined use of nicotinamide and sugars is combined with a compound having a carbonyl group and chlorphenesin (see, for example, Patent Document 4).

[0005] The above-mentioned conventional cosmetics refer to the suppression of crystal precipitation in cosmetics containing nicotinamide, but generally, they are used in combination with tranexamic acid, which has a higher crystal precipitation tendency than nicotinamide, to suppress its strong crystal precipitation tendency and provide an excessive crystal precipitation suppression effect.In addition, the yellowing of cosmetics over time other than crystal precipitation has not been fully studied.In light of this background, a method is required to prevent crystal precipitation and yellowing deterioration over time even when nicotinamide is blended in high concentration in cosmetics. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] WO2021-162074 publication [Patent Document 2] JP 2021-161111 A [Patent Document 3] JP 2021-161112 A [Patent Document 4] WO2023-085118 publication Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in consideration of the above problems, and an object of the present invention is to provide a component that suppresses crystal precipitation caused by nicotinamide, and a component that suppresses yellowing of cosmetics caused by nicotinamide due to exposure to light such as ultraviolet rays or LEDs. [Means for solving the problem]

[0008] As a result of further intensive research in order to achieve the above-mentioned object, the inventors have discovered that by combining nicotinamide with D-pantothenyl alcohol and phenoxyethanol, it is possible to obtain an effect of inhibiting crystal precipitation and an effect of inhibiting yellowing caused by exposure to light.

[0009] The inventors also discovered that the use of the crystal precipitation-inhibiting effect of the present invention in skin cosmetics can suppress crystal precipitation on the skin surface, thereby reducing the squeaky feeling of the skin after application, as a secondary effect.The inventors also discovered that the use of the yellowing-inhibiting effect of the present invention in skin cosmetics can suppress deterioration over time, particularly yellowing of cosmetics caused by exposure to light such as ultraviolet rays or LEDs, as a secondary effect, and thus completed the present invention.

[0010] The present invention is as follows. [1] The crystal precipitation inhibitor for skin cosmetics is derived from the following (A) and contains the following (B) and (C) as active ingredients. (A) Nicotinamide (B) Pantothenyl alcohol (C) Phenoxyethanol [2] The crystal precipitation inhibitor for skin cosmetics according to [1], wherein the blending ratios of (A) to (C) are such that (B) / (A) is 0.01 or more, (C) / (A) is 0.05 or more, and (((B)+(C) / (A)) is 0.1 or more.

[0011] [3] The present invention relates to an agent for inhibiting yellowing caused by light irradiation for use in skin cosmetics, which is derived from the following (A) and contains the following (B) and (C) as active ingredients. (A) Nicotinamide (B) Pantothenyl alcohol (C) Phenoxyethanol [4] The yellowing inhibitor for skin cosmetics according to [3], wherein the blending ratios of (A) to (C) are such that (B) / (A) is 0.01 or more, (C) / (A) is 0.05 or more, and (((B)+(C) / (A)) is 0.1 or more.

[0012] [5] The skin cosmetic contains the following (A) to (C). (A) Nicotinamide 1.0% by mass or more (B) Pantothenyl alcohol 0.01% by mass or more (C) Phenoxyethanol 0.05% by mass or more

[0013] [6] The method for inhibiting crystal precipitation derived from the following (A) is characterized by mixing the following (B) and (C) with the following (A). (A) Nicotinamide (B) Pantothenyl alcohol (C) Phenoxyethanol % [7] A method for suppressing yellowing caused by light irradiation resulting from the following (A), characterized by blending the following (B) and (C) with the following (A): (A) Nicotinamide (B) Pantothenyl alcohol (C) Phenoxyethanol % Effect of the Invention

[0014] The present invention can provide a component that inhibits crystal precipitation caused by nicotinamide and a component that inhibits yellowing of a preparation due to light irradiation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] The present invention will be described in detail below.

[0016] In this specification, the term "crystal precipitation inhibitor for skin cosmetics" refers to an agent for inhibiting crystal precipitation derived from nicotinamide or its derivatives or salts, or a complex with another component contained in the cosmetic. In addition, the term "yellowing inhibitor for skin cosmetics" refers to an agent for preventing the phenomenon in which the entire cosmetic denatures and discolors over time under high temperature conditions or under irradiation conditions such as ultraviolet light, fluorescent light, or LED light, turning the entire cosmetic yellow to brown.

[0017] <(A) Nicotinamide> Component (A) is nicotinamide. Nicotinamide, also known as nicotinamide and niacinamide, is an amide form of niacin (vitamin B3), and is a water-soluble vitamin with a molecular weight of 122.12 and a CAS registration number of 98-92-0. Nicotinamide is a component commonly used in cosmetics as a beauty ingredient for moisturizing, anti-inflammatory, whitening, etc., and is available as a commercially available cosmetic ingredient.

[0018] The (A) component is preferably contained in the cosmetic composition at 1% by mass or more. It has been known in recent years that a sufficient cosmetic effect, particularly an anti-wrinkle effect, is exhibited when the component is contained at 1% by mass or more. On the other hand, when the component is contained at 1% by mass or more, precipitation of nicotinamide tends to become significant.

[0019] <(B) Pantothenyl alcohol> The component (B) is pantothenyl alcohol. Pantothenyl alcohol, also called panthenol, is an analogue of pantothenic acid (vitamin B5) in which the carboxyl group is reduced to a hydroxyl group, and is a water-soluble vitamin with a molecular weight of 205.25 and a CAS registration number of 81-13-0. Pantothenyl alcohol is a component commonly used in cosmetics as a beauty component for moisturizing, anti-inflammatory, and improving barrier function, and is available as a commercially available cosmetic raw material. Pantothenyl alcohol has an asymmetric carbon atom, but it is preferable that the one used in the present invention is D-panthenol.

[0020] The (B) component is preferably contained in the cosmetic composition at 0.01% by mass or more. When the content is 0.01% by mass or more, sufficient cosmetic effects can be obtained, and the effect of inhibiting nicotinamide precipitation and yellowing, which was the object of the present invention, can be exhibited. In addition, from the viewpoint of non-stickiness, 2.0% by mass or less is more preferable.

[0021] <(C) Phenoxyethanol> Ingredient (C) is phenoxyethanol. Phenoxyethanol, also known as phenyl cellosolve, is a water-soluble compound with one molecule of phenol and one molecule of ethylene glycol bonded together by an ether bond, with a molecular weight of 138.16 and a CAS registration number of 122-99-6. Phenoxyethanol is an ingredient commonly used in cosmetics as a preservative and bacteriostatic agent, and is available in a variety of commercially available chemicals. It is available as a cosmetic ingredient.

[0022] The (C) component is preferably contained in the cosmetic composition in an amount of 0.05% by mass or more. When the amount is 0.05% by mass or more, sufficient crystal precipitation suppression effect and yellowing suppression effect can be exhibited. Moreover, from the viewpoint of non-stickiness, it is more preferable that the amount is 1.0% by mass or less.

[0023] In the present invention, the combination of component (A) with components (B) and (C) is necessary to suppress crystal precipitation and yellowing. Although the mechanism behind this has not been fully elucidated, it is speculated as follows.

[0024] First, it is speculated that the suppression of crystal precipitation is due to the fact that pantothenyl alcohol or phenoxyethanol is blended with nicotinamide, which slows down the drying speed of the cosmetic material attached to the container over time, and increases the amount of water remaining after drying, thereby suppressing the crystal precipitation of nicotinamide.Alternatively, it is speculated that the suppression of crystal precipitation of nicotinamide is due to the fact that pantothenyl alcohol or phenoxyethanol is blended with nicotinamide, which causes the nicotinamide molecules to be regularly arranged in the process of drying and concentrating, thereby suppressing the formation of crystal nuclei.

[0025] On the other hand, it is speculated that the inhibition of yellowing due to exposure to light is achieved by combining nicotinamide with pantothenyl alcohol or phenoxyethanol, which prevents nicotinamide and other ingredients in the cosmetic from being denatured by light, such as by oxidation or radical formation, thereby inhibiting the yellowing of nicotinamide itself, and even of the cosmetic in which nicotinamide is combined.

[0026] In the present invention, the blending ratios of (A) to (C) are desirably such that (B) / (A) is 0.01 or more, (C) / (A) is 0.05 or more, and (((B)+(C) / (A)) is 0.1 or more. This blending ratio provides sufficient inhibitory effect on crystal precipitation of nicotinamide, inhibitory effect on yellowing due to light exposure, and reduction in the squeaky feel of the skin after application. Even more preferably, if (((B)+(C) / (A)) is 1.5 or less, sufficient non-stickiness of the cosmetic and stability over time of the cosmetic are obtained.

[0027] <Other ingredients> In addition to the components described above, the skin cosmetic preparation of the present invention may contain other components, such as anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, oils, emollients, polymeric compounds, thickeners, polysaccharides, powders (colorants, resins, pigments), preservatives, fragrances, moisturizers, physiologically active ingredients, mineral salts, solvents, antioxidants, chelating agents, pearlizing agents, neutralizing agents, pH adjusters, plant extracts, enzymes, vitamins, amino acids, and other components, as appropriate, provided such components do not impair the object of the present invention.

[0028] Furthermore, the skin cosmetic of the present invention may contain an appropriate amount of a physiologically active ingredient within the scope of the present invention. A physiologically active substance is a substance that imparts some physiological activity to the skin when applied to the skin, and examples of such substances include whitening agents, anti-inflammatory agents, anti-aging agents, UV protection agents, astringents, antioxidants, blood circulation promoters, antibacterial agents, germicides, cooling agents, warming agents, wound healing promoters, irritation mitigators, analgesics, and cell activators.

[0029] <Skin cosmetics> The skin cosmetic of the present invention can be produced according to a conventional method. Examples of the skin cosmetic of the present invention include lotions, milky lotions, creams, beauty essences, gels, sheet masks, makeup, body lotions, body gels, body creams, face washes, face wash foams, body soaps, cleansing agents, makeup bases, etc. The dosage form can also be selected as desired depending on the purpose. That is, liquid, cream, gel, milky lotion, sheet, paste, etc. The skin cosmetic of the present invention is not limited to general skin cosmetic products, but includes quasi-drugs, designated quasi-drugs, external medicines, etc. EXAMPLES

[0030] The present invention will now be described in detail with reference to examples, but is not limited thereto. Prior to the examples, the test and evaluation methods employed in each example will be described.

[0031] 1. Crystal precipitation test <Evaluation method> Two drops (approximately 0.1 g) of the skin cosmetic of the present invention were placed on a black plastic plate and left to stand for 12 hours under conditions of 25°C and 60% humidity. The dried skin cosmetic remaining on the plastic plate was then evaluated for crystal precipitation by three volunteers by visual inspection and finger rubbing. The crystal precipitation was scored based on the scores given for each of the following "visual evaluation" and "touch evaluation" items, and the total score of the two scores was calculated. The average score given by the three volunteers was used to classify the results as follows:

[0032] <Contents of the visual evaluation score> 3 points: No white crystals are observed 2 points: Slightly white, but no visible crystals 1 point: Slightly powdery and white 0 points: White or transparent crystalline matter is visible <Score for texture> 3 points: Not feeling solid at all, very smooth 2 points: slightly smooth 1 point: Small solid crystals are slightly felt, but the material does not feel hard. 0 points: Feels like a hard, gritty solid <Evaluation criteria for hard crystal precipitation> ◎: The average score of 3 people was 5 points or more ○: The average score of 3 people was 3.5 points or more but less than 5 points △: The average score of the three participants was 2 points or more but less than 3.5 points. ×: The average score of the three participants was less than 2 points.

[0033] 2. Yellowing test due to light exposure <Evaluation method> 50 g of the skin cosmetic of the present invention was placed in a glass container and irradiated with a xenon lamp light source using a weather meter for about one week so that the total irradiation amount was 30 MJ. The appearance of the skin cosmetic removed thereafter was visually evaluated and compared with the appearance of the skin cosmetic before the test, and was evaluated using the following scores. <Evaluation criteria for yellowing over time> ◎: No yellowing at all, no difference in appearance from the skin cosmetic before the test ○: Slight yellowing compared to the skin cosmetic before the test, but almost no yellowing △: Slight yellowing that can be noticed without comparing before and after the test ×: Yellowing is clearly evident

[0034] 3. Squeakiness test when applied <Evaluation method> Five expert panelists applied 0.1 mL of the skin cosmetic of the present invention to the back of their hands, and after feeling that the skin had absorbed the cosmetic, evaluated the feeling of squeaking on the skin surface using the following rating method. The "squeaky feeling" in the present invention refers to the feeling of tightness, as if powder were on the skin, when the product was stroked horizontally on the skin. The test results were classified as follows, using the average scores of the five panelists.

[0035] <Score for sensory evaluation of non-squeakiness> 5 points: No creaking sensation 4 points: Almost no creaking sensation 3 points: Not much creaking 2 points: Slight creaking sensation 1 point: There is a creaking sensation <Evaluation criteria for non-creaking sensation> ◎: The average score of 5 people was higher than 4 points ○: The average score of 5 people was more than 3.5 points but less than 4 points △: The average score of 5 people was more than 2 points and less than 3.5 points. ×: The average score of 5 people was 2 points or less

[0036] 4. Stickiness test when applied <Evaluation method> Five expert panelists applied 0.1 mL of the skin cosmetic of the present invention to the back of their hands, and after feeling that the skin had absorbed the skin, they evaluated the stickiness of the skin using the following rating method. Here, stickiness in the present invention refers to the feeling of a sticky substance sticking to the skin when the skin on the back of the hand is touched perpendicularly with the other hand. The test results were classified as follows using the average score of the five panelists.

[0037] <Scores for sensory evaluation of non-stickiness> 5 points: no stickiness 4 points: Almost no stickiness 3 points: Not very sticky 2 points: Slightly sticky 1 point: Sticky <Evaluation criteria for non-stickiness> ◎: The average score of 5 people was 4 points or more ○: The average score of 5 people was 3 points or more but less than 4 points △: The average score of the 5 participants was 2 or more but less than 3 points. ×: The average score of 5 people was less than 2 points.

[0038] <Examples and Comparative Examples> Cosmetics having the respective formulations of Examples 1 to 16 and Comparative Examples 1 to 6 shown in Tables 1 and 2 were prepared by standard methods and evaluated by the respective test methods. The results are also shown in Table 1.

[0039] [Table 1]

[0040] [Table 2]

[0041] As is clear from Tables 1 and 2, all of the cosmetic compositions of the Examples using the components of the present invention had excellent performance. On the other hand, the Comparative Examples lacking any of the essential components were inferior in any of the following areas: crystal precipitation, absence of yellowing over time, absence of squeaky feeling, and absence of stickiness, and the object of the present invention could not be achieved.

[0042] Other formulation examples of the cosmetic of the present invention are given below as examples. The cosmetics of these examples were also examined for the above-mentioned precipitation of hard crystals, confirmation of the state of the crystals under a microscope, yellowing over time, and lack of stickiness, and were found to have excellent properties in all respects.

[0043] Example 17 (Lotion) (% by mass) (1) Nicotinamide 6.0% (2) Pantothenyl alcohol 0.3% (3) Phenoxyethanol 0.4% (4) Sodium hyaluronate 0.01% (5) Hydrolyzed collagen 0.01% (6) Retinol palmitate 0.01% (7) Dipropylene glycol 5.5% (8) Glycerin 4.0% (9) 1,3-butylene glycol 1.5% (10) Propanediol 1.0% (11) Citric acid, 0.05% (12) Potassium hydroxide 0.005% (13) Polyoxyethylene hydrogenated castor oil 0.1% (14) Polyoxyethylene sorbitan monolaurate (20E.O.) 0.1% (15) Disodium edetate 0.005% (16) Sodium pyrosulfite 0.001% (17) Polyglycerin-6 0.3% (18) Methyl gluceth-20 0.2% (19) Tripropylene glycol 0.2% (20) Hydrogenated soy lecithin 0.1% (21) Phytosterol 0.03% (22) Methylparaben: 0.05% (23) Centella asiatica extract 0.02% (24) Madecassoside 0.01% (25) Coix seed extract 0.05% (26) Ceramide NG 0.001% (27) Yeast extract 0.05% (28) Aloe extract 0.01% (29) Purified water remainder

[0044] (Production method) (1)-(5), (7)-(19), (22)-(25) were added to (29) and dispersed with a propeller until uniformly dissolved (Liquid A). (6), (20), (21) and (26) were dissolved in (7), and then added to Liquid A and uniformly dissolved to prepare a lotion.

[0045] Example 18 (Emulsion Sheet Mask) (% by mass) (1) Nicotinamide 4.0% (2) Pantothenyl alcohol 0.4% (3) Phenoxyethanol 0.3% (4) Ethanol 0.5% (5) 1,3-butylene glycol 8.0% (6) Glycerin 4.0% (7) Ascorbic acid 0.2% (8) PEG-60 hydrogenated castor oil 0.2% (9) Polysorbate 20 0.1% (10) PPG-13 decyltetradeceth-24 0.1% (11) Tocopherol 0.005% (12) Squalane 1.0% (13) Octyldodecyl myristate 0.01% (14) Dimethicone 1.0% (15) Isododecane 1.0% (16) (Acrylates / C10-30 alkyl acrylate) crosspolymer 0.04% (17) Carboxyvinyl polymer 0.08% (18) Potassium hydroxide 0.01% (19) Potassium phosphate 0.01% (20) Xanthan gum 0.1% (21) SACRAN 0.01% (22) Hexanediol 0.1% (23) Ethylhexylglycerin 0.1% (24) Methylparaben 0.1% (25) Purified water remainder

[0046] (Production method) (11) to (15) are heated to 50°C and uniformly dissolved (Liquid A). (1) to (10) and (16) to (24) are added to (25), and heated to 50°C and uniformly dissolved (Liquid B). Liquid B is added to Liquid A and dispersed in a homogenizer until uniform, to prepare a milky beauty essence for sheet masks. A nonwoven fabric (material: rayon) is impregnated with this beauty essence, which is then filled into an aluminum pouch to prepare a sheet mask.

Claims

1. A crystal precipitation inhibitor for skin cosmetics, comprising the following (B) and (C) as active ingredients, and derived from the following (A): (A) nicotinamide. (B) Pantothenyl alcohol (C) Phenoxyethanol

2. The blending ratio of the (A) to (C) is 2. The crystal precipitation inhibitor for skin cosmetics according to claim 1, wherein (B) / (A) is 0.01 or more, (C) / (A) is 0.05 or more, and (((B)+(C) / (A))) is 0.1 or more.

3. An agent for inhibiting yellowing caused by light irradiation for use in skin cosmetics, which is derived from the following (A) and contains the following (B) and (C) as active ingredients: (A) Nicotinamide (B) Pantothenyl alcohol (C) Phenoxyethanol

4. The blending ratio of the (A) to (C) is 4. The yellowing inhibitor for skin cosmetics according to claim 3, wherein (B) / (A) is 0.01 or more, (C) / (A) is 0.05 or more, and (((B)+(C) / (A))) is 0.1 or more.

5. A skin cosmetic composition comprising the following (A) to (C): (A) Nicotinamide 1.0% by mass or more (B) Pantothenyl alcohol 0.01% by mass or more (C) Phenoxyethanol 0.05% by mass or more

6. A method for inhibiting crystal precipitation derived from the following (A), comprising blending the following (B) and (C) with the following (A): (A) Nicotinamide (B) Pantothenyl alcohol (C) Phenoxyethanol

7. A method for suppressing yellowing caused by light irradiation resulting from the following (A), characterized by comprising blending the following (B) and (C) with the following (A): (A) Nicotinamide (B) Pantothenyl alcohol (C) Phenoxyethanol %

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