Cosmetic product containing pyridoxines

Abstract

The present invention aims to provide a cosmetic containing a pyridoxine and having excellent stability and usability. The cosmetic of the present invention is characterized by comprising: (A) pyridoxine, a salt or a derivative thereof; (B) ethyl ascorbic acid; and (C) a higher fatty acid or a higher alcohol which is liquid at 25°C.

Description

Technical Field

[0001] This invention relates to cosmetics containing pyridoxine, its salts or derivatives, and exhibiting excellent stability and usability. Background Technology

[0002] Pyridoxine, a water-soluble vitamin belonging to the vitamin B6 group, and its salts or derivatives (hereinafter sometimes referred to as "pyridoxine derivatives") are known to have sebum-suppressing effects. In order to improve sebum problems such as oily skin, stickiness, and acne, it is used in various cosmetics such as skin care products, makeup bases, sunscreens, and makeup.

[0003] However, pyridoxines are prone to decomposition over time when exposed to light, causing coloring in cosmetics. Therefore, it is necessary to improve their stability in cosmetics.

[0004] As an attempt to improve the stability of pyridoxine derivatives in cosmetics, for example, Patent Document 1 proposes a dehydrochlorinated derivative of pyridoxine hydrochloride and an acidic compound such as ascorbic acid or its derivative. Table 2-1 shows that by using any one of ascorbic acid, ascorbate glucoside, or 3-O-ethyl ascorbic acid in the dehydrochlorinated derivative of pyridoxine hydrochloride, coloring is suppressed and stability is improved. Furthermore, Table 2-2 shows that the stability is further improved by adding sodium metabisulfite or sodium citrate as stability enhancers.

[0005] However, cosmetics containing pyridoxine tend to produce a slippery feeling during application, poor skin integration, stickiness when dry, a rough feeling after application, and a film-like feeling. Furthermore, when combined with ascorbic acid or its derivatives to improve the stability of pyridoxine, their usability is sometimes significantly impaired.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2017-123833 Summary of the Invention

[0009] The problem the invention aims to solve

[0010] The purpose of this invention is to provide cosmetics containing pyridoxines that have excellent stability and usability.

[0011] Solution for solving the problem

[0012] In order to solve the above-mentioned problems, the inventors have repeatedly conducted in-depth research and found that by combining ethyl ascorbic acid and higher fatty acids or higher alcohols that are liquid at 25°C with cosmetics containing pyridoxine, it is possible to obtain cosmetics that stably retain pyridoxine and have excellent usability, thus completing the present invention.

[0013] That is, the cosmetic of the present invention is characterized in that it comprises:

[0014] (A) Pyridoxine, its salts or derivatives;

[0015] (B) Ethyl ascorbic acid; and

[0016] (C) Higher fatty acids or higher alcohols are liquid at 25°C.

[0017] The effects of the invention

[0018] By configuring the cosmetic of the present invention as described above, it is possible to achieve a cosmetic that not only stably maintains pyridoxine but also has excellent usability. Detailed Implementation

[0019] The cosmetic of the present invention is characterized in that it comprises: (A) pyridoxine, its salt or derivative; (B) ethyl ascorbic acid; and (C) a higher fatty acid or higher alcohol that is liquid at 25°C. The components constituting the cosmetic of the present invention are described in detail below.

[0020] <(A) Pyridoxine, its salts or derivatives>

[0021] The (A) pyridoxine, its salts or derivatives used in this invention can be used alone or in combination of two or more.

[0022] There are no particular restrictions on salts of pyridoxine, as long as they are pharmaceutically, pharmacologically (in pharmaceutical manufacturing), or physiologically acceptable. Examples of such compounds include the following.

[0023] (i) Organic acid salts

[0024] Monocarboxylic acids (acetates, trifluoroacetates, butyrates, palmitates, and stearates, etc.)

[0025] Polycarboxylate salts (fumarate, maleate, succinate, and malonate, etc.)

[0026] Hydroxycarboxylate salts (lactates, tartrates, and citrates, etc.)

[0027] Organic sulfonates (methanesulfonates, toluenesulfonates, and p-toluenesulfonates, etc.)

[0028] (ii) Inorganic acid salts

[0029] Hydrochloride, sulfate, nitrate, hydrobromide, and phosphate, etc.

[0030] (iii) Salts formed with organic bases

[0031] Salts formed with organic amines such as methylamine, triethylamine, triethanolamine, morpholine, piperazine, pyrrolidine, tripyridine, and methylpyridine

[0032] (iv) Salts formed with inorganic bases

[0033] ammonium salts

[0034] Salts formed with alkali metals (such as sodium and potassium),

[0035] Salts formed with alkaline earth metals (such as calcium and magnesium), and

[0036] Salts formed with metals such as aluminum.

[0037] Among them, inorganic acid salts of pyridoxine are preferred, hydrochloride or phosphate of pyridoxine are more preferred, and hydrochloride of pyridoxine is even more preferred.

[0038] Some derivatives of pyridoxine are included in the above-mentioned salts, especially substances that have pyridoxine activity and are stabilized and lipid-soluble by phosphorylation, esterification, etc. Examples include pyridoxine cyclic phosphate, pyridoxine glycyrrhetinic acid ester, pyridoxine dioctanoate, pyridoxine dipalmitate, pyridoxine tri-hexyldecanoate, pyridoxine tripalmitate, etc., but are not limited to these.

[0039] Relative to the total amount of cosmetics, the amount of (A) pyridoxine, its salts, or derivatives is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and further preferably 10% by mass or less, more preferably 5% by mass or less. Therefore, examples of the range of the amount can be 0.001 to 10% by mass or 0.01 to 5% by mass. If it is within this range, the sebum-suppressing effect of (A) pyridoxine, its salts, or derivatives can be fully exerted.

[0040] <(B) Ethyl ascorbic acid>

[0041] The (B)-ethyl ascorbic acid (2-O-ethyl ascorbic acid) used in this invention is an ascorbic acid derivative with improved stability, and possesses various physiological activities similar to ascorbic acid. (B)-ethyl ascorbic acid is known to exert antioxidant, whitening, and collagen and / or hyaluronic acid production-promoting effects, and is widely used as an active ingredient in cosmetics and topical skin agents.

[0042] (B) The amount of ethyl ascorbic acid incorporated relative to the total amount of the cosmetic is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, and preferably 1% by mass or less, more preferably 0.5% by mass or less. Therefore, examples of the incorporation amount range include 0.001 to 1% by mass and 0.01 to 0.5% by mass. If it is within this range, the usability of the cosmetic will not be significantly impaired, and the stability of (A) pyridoxine can be sufficiently improved.

[0043] <(C) Higher fatty acids or higher alcohols that are liquid at 25°C>

[0044] The higher fatty acids or higher alcohols (C) used in this invention that are liquid at 25°C are not particularly limited as long as they are liquid at 25°C. One type can be used alone, or two or more types can be used together.

[0045] Examples of higher alcohols that are liquid at 25°C include 2-ethylhexanol, 6-methyl-2-heptanol, isononol, isodecanol, isoundecanol, isodecanol, 2-butyloctanol, isotrigine, isotetradecanol, isopententane, isohexadecanol, 2-hexyldecanol, isohexadecanol, isostearyl alcohol, isononadecanol, isoeicosanol, octyldodecanol, isoeicosanol, 18-methyleicosanol, isoeicosanol, and 2-decyltetradecanol.

[0046] Examples of higher fatty acids that are liquid at 25°C include isononanoic acid, isodecanic acid, dimethyloctanoic acid, isoundecanoic acid, isodecanonicic acid, isotriadecanoic acid, isotriadecanoic acid, isotriadecanoic acid, isotriadecanoic acid, isohexadecanonicic acid, isostearic acid, isononadecanonicic acid, isoeicosanoic acid, 2-ethylhexanoic acid, 2-butyloctanoic acid, 2-hexyldecanoic acid, 2-octyldodecanoic acid, 2-decyltetradecanoic acid, 2-dodecylhexadecanoic acid, 2-tetradecyloctadecanoic acid, 2-hexadecyleicosanoic acid, undecenoic acid, myristoleic acid, palmitoleic acid, oleic acid, linoleic acid, linolenic acid, eicosapentaenoic acid, docosahexaenoic acid, erucic acid, brassinolic acid, and arachidonic acid.

[0047] Among them, isostearic acid, oleic acid, isostearyl alcohol, and octyldodecyl alcohol are particularly preferred from the perspective of improving usability.

[0048] (C) The amount of higher fatty acids or higher alcohols that are liquid at 25°C is preferably 0.5% by mass or less, more preferably 0.3% by mass or less, relative to the total amount of the cosmetic. Furthermore, there is no particular limitation on the lower limit of the amount, but it is preferably 0.001% by mass or more, more preferably 0.005% by mass or more. Therefore, examples of the range for the amount can be 0.001 to 0.5% by mass, 0.005 to 0.3% by mass, etc. If it is within this range, the stability of (A) pyridoxines will not be impaired, and the usability of the cosmetic can be sufficiently improved.

[0049] <(A) / (B) ratio>

[0050] In the cosmetic of the present invention, the combined mass ratio of (A) pyridoxine, its salt or derivative to (B) ethyl ascorbic acid ((A) / (B) ratio) is preferably less than 3, more preferably less than 2.5, and even more preferably less than 2.

[0051] By adjusting the (A) / (B) ratio to below 3, excellent results can be achieved in both the stability of (A) pyridoxines and the usability of cosmetics.

[0052] <(C) / Total Oil Ratio>

[0053] The cosmetic of the present invention may contain oils other than (C) higher fatty acids or higher alcohols that are liquid at 25°C. The mass ratio of component (C) to all oils including component (C) ((C) / total oil ratio) is preferably 10% by mass or more, more preferably 20% by mass or more. If it is within this range, even when combined with (A) pyridoxine and (B) ethyl ascorbic acid, its usability can be sufficiently improved.

[0054] <Optional Ingredients>

[0055] In the cosmetics of the present invention, in addition to the ingredients (A) to (C) mentioned above, other ingredients commonly used in cosmetics may be added without impairing the effects of the present invention. For example, in addition to oils, aqueous solvents, and moisturizers other than ingredient (C), antioxidants, chelating agents, preservatives, and (daily) fragrances may also be added as needed.

[0056] There are no special restrictions on oils that are not usually used in cosmetics, except for ingredients (C). Examples include silicone oil, hydrocarbon oil, and ester oil.

[0057] Examples of silicone oils include linear and cyclic polysiloxanes such as dimethyl polysiloxane, methylphenyl polysiloxane, methylhydropolysiloxane, decamethyl polysiloxane, dodecyl polysiloxane, tetramethyltetrahydropolysiloxane, cyclotetradimethylsiloxane, and cyclopentadimethylsiloxane.

[0058] Examples of hydrocarbon oils include liquid paraffin, isohexadecane, ceresin, pterosinane, paraffin wax, isoparaffin, pure ceresin, petrolatum, microcrystalline wax, hydrogenated polyisobutylene, olefin oligomers, and volatile hydrocarbon oils (such as isododecane, undecane, and tridecane).

[0059] Examples of ester oils include isopropyl myristate, cetyl ethylhexanoate, octyl dodecyl myristate, isopropyl palmitate, butyl stearate, hexyl laurate, myristyl myristate, decyl oleate, hexyl decyl dimethyl ethylhexanoate, cetyl lactate, myristyl lactate, isocetyl stearate, isocetyl isostearate, cholesterol hydroxystearate, ethylene glycol di-2-ethylhexanoate, dipentaerythritol fatty acid ester, N-alkyl diol monoisostearate, neopentyl glycol didecanoate, diisostearate malate, glyceryl di-2-heptyl undecanoate, trimethylolpropane tri(ethylhexanoate), trimethylolpropane tri(ethylhexanoate), and trimethylolpropane tri(ethylhexanoate). Propane triisostearate, pentaerythritol tetra(ethylhexanoate), glyceryl tri(2-ethylhexanoate), cetyl ethylhexanoate, ethylhexyl palmitate, glyceryl trimyristicate, glyceryl tri-2-heptylundecanoate, castor oil fatty acid methyl ester, oleyl alcohol oleate, acetylglycine ester, 2-heptylundecyl palmitate, diisobutyl adipate, di(2-heptylundecyl)adipate, ethyl laurate, diethylhexyl sebacate, 2-hexyldecyl myristate, 2-hexyldecyl palmitate, 2-hexyldecyl adipate, diisopropyl adipate, diethylhexyl succinate, ethyl acetate, butyl acetate, amyl acetate, and triethyl citrate, etc.

[0060] In the cosmetic of the present invention, the total amount of oil, including component (C), is preferably 0.001% by mass or more relative to the total amount of the cosmetic, and more preferably 2% by mass or less. Therefore, examples of the range of the amount can be 0.001 to 2% by mass.

[0061] Examples of aqueous solvents include water (purified water, ion-exchanged water, and tap water, etc.), lower alcohols, or mixtures thereof.

[0062] Examples of humectants include polyoxyethylene-polyoxyethylene copolymer dialkyl ethers, 1,3-butanediol (BG), polyethylene glycol (PEG), propylene glycol, dipropylene glycol (DPG), hexanediol, glycerin, diglycerin, xylitol, maltitol, maltose, and D-mannitol.

[0063] In particular, when combined with polyethylene glycol (PEG) with a molecular weight of 300 to 2000, it can improve skin compatibility and reduce stickiness, thus further enhancing the usability of cosmetics. The molecular weight of the PEG is preferably 300 or higher, and more preferably 2000 or lower, and even more preferably 1500 or lower. Here, molecular weight refers to the mass-average molecular weight of the compound, which can be determined, for example, by GPC (gel permeation chromatography).

[0064] When incorporating polyethylene glycol with a molecular weight of 300 to 2000, the amount is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and further preferably 5% by mass or less, more preferably 2% by mass or less, relative to the total amount of cosmetics. Therefore, examples of the incorporation amount range include 0.01 to 5% by mass and 0.1 to 2% by mass.

[0065] <Uses and Forms>

[0066] The cosmetic of the present invention can stably combine with (A) pyridoxine, and therefore can be used in cosmetics that inhibit sebum secretion.

[0067] The cosmetic form of the present invention is not particularly limited. Any form that is used in cosmetics, such as lotion, serum, emulsion, cream, and gel, can be widely applied. Generally, in oil-rich cosmetics such as emulsions, (A) pyridoxine compounds can remain relatively stable. However, the present invention can stably incorporate (A) pyridoxine compounds even in lotions, serums, and the like, where high oil content cannot be incorporated.

[0068] Example

[0069] The present invention is further described in detail below with reference to specific examples, but the invention is not limited to these examples in any way. Unless otherwise specified, the amount of each ingredient is expressed as a percentage of mass relative to the cosmetic product. Before detailing the various examples, the evaluation methods used are described.

[0070] <Stability of pyridoxine>

[0071] Each cosmetic product was placed in a light-proof glass threaded tube. The amount of pyridoxine after storage at 0°C for one month and after storage at 50°C for one month were determined according to the general test method of Japanese Standard for Pharmaceutical Raw Materials 2006 - High Performance Liquid Chromatography. The residual rate of pyridoxine (%) was calculated as ([amount of pyridoxine after storage at 50°C for one month] / [amount of pyridoxine after storage at 0°C for one month] × 100) to evaluate stability.

[0072] <Usability>

[0073] The usability of each cosmetic product was investigated based on the following criteria: (i) no slippery feeling during application, (ii) good blending, (iii) no sticky feeling when dry, (iv) no astringent feeling after application, and (v) no film-like feeling.

[0074] [Judgment Criteria]

[0075] A: Very good

[0076] B: Good

[0077] C: Can fully allow

[0078] D: Bad

[0079] <Reference Example>

[0080] Cosmetics as shown in Table 1 below were prepared, and their stability was evaluated based on the evaluation methods and criteria described above. The purpose of this reference example is to investigate the extent to which (B) ethyl ascorbic acid and other antioxidants affect the stability of (A) pyridoxine derivatives without the presence of ingredient (C). The evaluation results are also presented.

[0081] [Table 1]

[0082]

[0083] As shown in Table 1, among antioxidants widely used in cosmetics, (B) ethyl ascorbic acid exhibits the best stability of pyridoxine.

[0084] <Manufacturing Example>

[0085] The cosmetics listed in Tables 2A to 2C below were prepared and evaluated based on the evaluation methods and criteria described above. The evaluation results are also presented.

[0086] [Table 2A]

[0087]

[0088] [Table 2B]

[0089]

[0090] [Table 2C]

[0091]

[0092] As shown in Tables 2A to 2C, in the absence of (C) higher fatty acids or higher alcohols that are liquid at 25°C, the usability evaluations were all poor in the case of using (A) pyridoxine alone and in the case of using (A) pyridoxine and (B) ethyl ascorbic acid together (Manufacturing Examples 1 and 2).

[0093] Furthermore, even when only oils that are liquid at 25°C but are not higher fatty acids or higher alcohols are added, usability cannot be adequately improved (manufacturing examples 3-7).

[0094] On the other hand, it was confirmed that by combining components that are liquid at 25°C (isostearic acid, isostearyl alcohol, oleic acid and octyldodecyl alcohol), usability was improved (manufacturing examples 8-27).

[0095] In addition, it was confirmed that good usability could be maintained even when other oils were added to component (C) (manufacturing examples 18-25), and it was confirmed that a mass ratio of (A) pyridoxine to (B) ethyl ascorbic acid ((A) / (B) ratio) of less than 3 was preferred (manufacturing examples 8, 26 and 27).

[0096] The cosmetics listed in Table 3 below were prepared. The usability of the cosmetics was evaluated relative to Manufacturing Example 8, and the following criteria were used for judgment. The evaluation results are also shown.

[0097] [Judgment Criteria]

[0098] +2: Excellent

[0099] +1: Excellent

[0100] 0: Equal

[0101] -1: Slightly worse

[0102] -2: Difference

[0103] [Table 3]

[0104]

[0105] As shown in Table 3, if polyethylene glycol with a molecular weight in the range of 300 to 2000 is used, all or any of the following aspects are improved compared to the cosmetic of Manufacturing Example 8: no slippery feeling during application, good blending, and no stickiness when drying (Manufacturing Examples 29 to 33).

[0106] On the other hand, if polyethylene glycol with a molecular weight of 20,000 is used, the slippery feeling during application becomes more pronounced, and usability is confirmed to be reduced (manufacturing example 28).

Claims

1. A cosmetic product comprising: (A) Pyridoxine, its salts or derivatives; (B) Ethyl ascorbic acid; and (C) Higher fatty acids or higher alcohols are liquid at 25°C.

2. The cosmetic product according to claim 1, wherein, (C) The higher fatty acids or higher alcohols that are liquid at 25°C are selected from one or more of isostearic acid, oleic acid, isostearyl alcohol, and octyldodecyl alcohol.

3. The cosmetic product according to claim 1, wherein, The combined mass ratio of (A) pyridoxine, its salts or derivatives to (B) ethyl ascorbic acid ((A) / (B) ratio) is less than 3.

4. The cosmetic product according to claim 1, wherein, (B) The amount of ethyl ascorbic acid in the total amount of cosmetic product is 0.001 to 1% by mass.

5. The cosmetic product according to claim 1, wherein, (C) The amount of higher fatty acids or higher alcohols that are liquid at 25°C relative to the total amount of cosmetics is less than 0.5% by mass.

6. The cosmetic product according to claim 1, wherein, The amount of all oil components, including (C) higher fatty acids or higher alcohols that are liquid at 25°C, is 0.001 to 2% of the total amount of cosmetics.

7. The cosmetic product according to claim 1, wherein, The mass ratio of component (C) relative to all oils, including higher fatty acids or higher alcohols that are liquid at 25°C ((C) / total oil ratio), is 10% or more by mass.

8. The cosmetic according to claim 1, further comprising polyethylene glycol with a molecular weight of 300 to 2000.

9. The cosmetic product according to claim 1, wherein, Cosmetics that suppress sebum secretion.

Images