TW201304808A - Oil-in-water-type external preparation for skin - Google Patents

Abstract

Provided is an oil-in-water-type external preparation for the skin, which contains a high-molecular-weight polyethylene glycol, and has excellent rich texture, excellent long-term stability in a broad environmental temperature range from a lower temperature to a higher temperature and a good sensation upon application. The oil-in-water-type external preparation for the skin is characterized by comprising (a) a high-molecular-weight polyethylene glycol, (b) a higher alcohol, (c) sodium N-stearoyl-N-methyltaurine in an amount of less than 2.0 mass%, and (d) a nonionic surfactant. The high-molecular-weight polyethylene glycol is preferably polyethylene glycol 20000, and the nonionic surfactant (d) is preferably contained in an amount of 1.0 to 10.0 mass% relative to the total amount of the oil-in-water-type external preparation for the skin.

Description

Oily skin external preparation for water

The present invention relates to an oil-based skin external preparation, and more particularly to an oil-based skin having an excellent thick feeling and having excellent stability over time at a wide range of ambient temperatures from low temperature to high temperature. External preparation.

The oil-in-water emulsion composition is suitable for use in skin cosmetics such as skin creams because of its moisturizing and refreshing feeling. However, since the emulsified composition is usually formed by forcibly dispersing an aqueous phase and an oil phase which are not originally mixed by an emulsifier, it may become very unstable depending on the ingredients to be formulated, causing separation of the phases (from the separation). Slynesis).

For example, various electrolytes such as an organic acid salt or an inorganic acid salt are added for the purpose of imparting moisturizing, astringent, and keratinolytic effects to the skin, or a moisturizing effect or the like is imparted to the skin for good ductility. Polar oils are formulated, but these are known to impair the stability over time of the oily emulsified composition in water.

For this reason, a method for stably disposing these components in an oily skin external preparation for use in water is known. As a representative example, a method of blending a water-soluble polymer such as Sanxian gum to impart a structural viscosity to an aqueous phase is known. However, in order to maintain the stability under long-term storage, it is necessary to mix a large amount of the polymer component, thereby causing mucus or stretching of the mucus or stickiness during use, and the feeling of use is markedly impaired.

In view of this situation, the following methods are disclosed: in order not to rely on Sanxianjiao, etc. The water-soluble polymer improves the stability over time, and the long-chain sulfonate-type anionic surfactant and the higher alcohol are blended in a gel-like composition having a viscosity of a specific value or more (Patent Documents 1 and 2) A specific polyoxyethylene fatty acid sorbitan anhydride, an anionic surfactant, and a nonionic surfactant having an IOB (Inorganic Organic Balance) value of 1.6 or more, and a higher alcohol having a specific structure are specified. The ratio is combined and formulated (Patent Document 3) and the like (hereinafter referred to as "Paragraph A").

On the other hand, in order to obtain a strong feeling of use when applying a cosmetic to the skin, that is, a "rich feeling", there is a case where a high molecular weight polyethylene glycol is formulated. The high molecular weight polyethylene glycol-based ethylene oxide unit has a total average addition of a polymer compound having a molar number of 220 to 4,500, wherein the polyethylene glycol 20000 (PEG 20000) exhibits a thick feeling. Significantly, it can be preferably used. However, when a high molecular weight polyethylene glycol is blended in the oil-type emulsified composition in water, the consistency is improved, but the stability with time is impaired, and the slurry is generated. Heretofore, a method for stabilizing an oil-in-water emulsion composition containing a high molecular weight polyethylene glycol has not been proposed.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2005-132808

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2008-44866

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2008-88129

That is, it is still expected to stably mix high molecular weight polyethylene glycol in water. A new method in skin external preparations.

An object of the present invention is to provide a high molecular weight polyethylene glycol which can improve the consistency of the formulation and which has an effect on the stability of the formulation, has excellent stability over time at a wide range of ambient temperatures, and has a good feeling in use. Oily skin external preparation.

The present inventors have made an effort to solve the above problems, and as a result, found that a high-molecular-weight polyethylene glycol containing an aqueous oil-based skin external preparation is prepared by blending a higher alcohol, a nonionic surfactant, and N-hard fat. The present invention can be obtained by using a mercapto-N-methyltaurine sodium to obtain an aqueous oil-type skin external preparation which has a sufficient thick feeling and is non-sticky, has a good feeling of use, and is excellent in stability over time.

Thus, the present invention has the following main features.

(1) An oily skin external preparation containing (a) a high molecular weight polyethylene glycol, (b) a higher alcohol, (c) less than 2.0% by mass of N-stearyl-N-methyl bovine Sodium sulfonate, and (d) a nonionic surfactant.

(2) The oily skin external preparation according to (1), wherein (a) the high molecular weight polyethylene glycol is polyethylene glycol 20000.

(3) The oily skin external preparation according to (1) or (2), which comprises (d) a nonionic surfactant in an amount of from 1.0 to 10.0% by mass based on the total amount of the oily skin external preparation in water.

The oil-in-water type external preparation for skin of the present invention is prepared by formulating a higher alcohol, N-stearyl fat by using an oil-based skin external preparation containing a high molecular weight polyethylene glycol. Sodium thiol-N-methyltaurate and a nonionic surfactant can have significantly superior stability over time while inhibiting the generation of off-gas. Further, since it is not necessary to mix a water-soluble polymer such as Sanxian gum in a large amount, there is no deterioration in the feeling of use due to the occurrence of stickiness or the like.

Further, since a sufficient amount of high molecular weight polyethylene glycol can be stably formulated, it is excellent in a rich feeling, and a rich feeling of use can be obtained.

For example, in the above-mentioned Patent Documents 1 and 2, when N-nonylmethyltaurate and a nonionic surfactant are used in combination, the stability at a high temperature is insufficient (paragraph A). However, it has been found that in the case of blending a high molecular weight polyethylene glycol, N-indole methyl taurate, especially N-stearyl sulfonyl-N-methyl taurine, is used in combination with higher alcohols. Sodium and nonionic surfactants improve temporal stability without compromising thick feel and tactile sensation, a finding that is contrary to the prior art disclosure.

The oil-in-water type skin external preparation of the present invention is characterized by comprising (a) a high molecular weight polyethylene glycol, (b) a higher alcohol, and (c) less than 2.0% by mass of N-stearyl-N-methyl Sodium taurate, and (d) a nonionic surfactant. Hereinafter, the present invention will be described in detail.

<(a) High molecular weight polyethylene glycol>

The high molecular weight polyethylene glycol refers to a polyethylene glycol having an average molecular weight of 10,000 to 25,000, more preferably 15,000 to 25,000, which is semi-solid at normal temperature. When the average molecular weight is less than 10,000, the aqueous oily skin external preparation is difficult to exhibit a sufficient thick feeling, and when it exceeds 25,000, it is confirmed that it is difficult to emulsify, and the preparation tends to be unstable. High molecular weight polyethylene glycol as long as it is acceptable The cosmetic product is not particularly limited, and for example, a product sold by Sanyo Chemical Industry Co., Ltd. under the trade name "PEG-20000" can be preferably exemplified.

The high molecular weight polyethylene glycol is formulated in an amount of 5.0% by mass or less, preferably 0.5% to 3.0% by mass, and more preferably 1.0% to 3.0% by mass based on the total amount of the oily skin external preparation in water. If the blending amount is less than 0.5% by mass of the oily skin external preparation, the oily skin type external preparation is difficult to exhibit a sufficient thick feeling, and if it exceeds 5.0% by mass, the oily skin external preparation is stable over time. The tendency to decline in sex has become significant.

<(b) higher alcohol>

The higher alcohol is not particularly limited as long as it can be used in the fields of cosmetics, pharmaceuticals, quasi-drugs, and the like, and examples thereof include saturated linear monohydric alcohols and unsaturated monohydric alcohols. Examples of the saturated linear monohydric alcohol include dodecyl alcohol (=lauryl alcohol), tridecyl alcohol, tetradecyl alcohol (=myristyl alcohol), pentadecyl alcohol, cetyl alcohol (=cephthyl alcohol), heptadecyl alcohol, Octadecanol (=stearyl alcohol), nonadecanol, pentaerythritol (=aravian alcohol), twenty-one alcohol, twenty-diol (=behenyl alcohol), tris-triol, twenty-four alcohol (= Brazil palmitol), barcoal alcohol, hexadecanol (= wax alcohol), and the like. Examples of the unsaturated monohydric alcohol include retrooleyl alcohol and the like. In the present invention, a saturated linear monohydric alcohol is preferred in terms of stability and the like. These may be used alone or in combination of two or more.

The blending amount of the higher alcohol is 10.0% by mass or less, preferably 1.0% to 7.0% by mass, and more preferably 2.0% to 6.0% by mass based on the total amount of the oily skin external preparation in water. If it is less than 1.0% by mass, there is a tendency that sufficient stability with time is not obtained. If it is more than 10.0% by mass, apply it to the skin. On the skin, it is observed that the tendency of the extension to become stagnant or to produce a sticky feeling is not good.

<(c) N-stearyl-N-methyl taurate sodium>

The invention of the present application is characterized in that, when combined with other essential components, N-stearyl-N-methyl group represented by the following formula (I) is particularly selected from N-fluorene methyl taurate. Sodium taurate is formulated.

R ₁ CO-N(CH ₃ )-(CH ₂ ) ₂ SO ₃ Na (I)

In the formula (I), the fluorenyl moiety (R ₁ CO-) represents a stearyl group of a fatty acid residue having 18 carbon atoms.

N-stearyl sulfonyl-N-methyl taurate is a surfactant which has been formulated in the cosmetics and the like described in the above Patent Documents 1 to 3, and is preferably exemplified by daylight chemistry. A company that sells its products under the name "NIKKOL SMT".

The total amount of the N-stearyl sulfonyl-N-methyltaurine sodium relative to the oily skin external preparation in water is less than 2.0% by mass, preferably 0.1 to 1.0% by mass, and more preferably 0.1 to 0.5% by mass. . When the amount of the formulation is less than 0.1% by mass based on the total amount of the oily skin external preparation in water, the time stability of the oily skin external preparation in water cannot be sufficiently ensured. In addition, when the amount is 2.0% by mass or more, the sticky feeling caused by the sodium N-stearyl sulfonyl-N-methyltaurate itself is remarkable, and the tendency to use the oily skin external preparation is lowered. .

<(d) Nonionic surfactant>

The non-ionic surfactant is a user who is usually used in cosmetics, and may be hydrophilic or hydrophilic, and may be used singly or in combination of two or more kinds as needed.

The lipophilic nonionic surfactant is not particularly limited, and for example, POE (Polyoxyethylene, polyoxyethylene) (3) oleyl ether, POE (3) lauryl ether, glyceryl monostearate, diglyceryl monostearate, decaglyceryl pentastearate, hexaglyceryl tristearate Ester, POE (2) nonylphenyl ether, glyceryl palmitate, glyceryl isostearate, propylene glycol stearate, PEG (Polyethylene glycol) (5-7) hydrogenated castor oil, PEG ( 5~20) glyceryl triisostearate, PEG (3~8) glyceryl isostearate, PEG (3~15) glyceryl tristearate, PEG (5~10) glycerol trioleate, PEG (10~40) hydrogenated castor oil triisostearate, PEG (5~30) hydrogenated castor oil isostearate, POE sorbitol stearate, POE sorbitol isostearate, POE sorbitol oleate and the like.

Further, the hydrophilic nonionic surfactant is not particularly limited, and examples thereof include POE (10-40) glyceryl monoisostearate, hexaglycerol monolaurate, decaglyceryl monolaurate, and ten glycerin monomyristate. Acid ester, decaglyceryl monostearate, decaglycerin monooleate, POE (40~60) castor oil, POE (30~100) hardened castor oil, PEG (40~60) glyceryl triisostearate , PEG (10~60) glyceryl isostearate, PEG (40~60) glycerol trioleate, PEG (40~60) hydrogenated castor oil isostearate, PEG-60 hydrogenated castor oil Fatty acid ester, PEG (40~60) hydrogenated castor oil laurate, POE (7-20) cetyl ether, POE (10-50) oleyl ether.

The amount of the nonionic surfactant to be added is 10.0% by mass or less, preferably 1.0 to 7.0% by mass, and more preferably 2.0 to 6.0% by mass based on the total amount of the oily skin external preparation in water. If it is less than 1.0% by mass, sufficient stability with time is not obtained, and if it is more than 10.0% by mass, the feeling of stickiness of the nonionic surfactant itself is generated, so that the touch is not good.

<Other than the above ingredients>

The oily oil type skin external preparation of the present invention is an oily type emulsion composition, and water and oil blending are necessary.

As the oil component, it is usually selected from the users of the cosmetic in the range of non-destructive stability. Examples of preferred oil components include hydrocarbon oils, polyoxygenated oils, liquid fats and oils, and ester oils.

As the hydrocarbon oil, liquid paraffin, squalane, squalene, paraffin, isoparaffin, ozokerite, petrolatum, hydrogenated polydecene, or the like can be used.

As the polyoxygenated oil, for example, a chain polyfluorene such as dimethyl polyoxyalkylene, methylphenyl polyoxyalkylene or methyl hydrogen polyoxyalkylene; octamethylcyclotetraoxane or ten; a cyclic polyfluorene oxide such as methylcyclopentaoxane or dodecamethylcyclohexaoxane; a polyoxyxylene resin or a polyoxyxene rubber which forms a three-dimensional network structure.

As liquid fat, there are palm oil, palm kernel oil, linseed oil, tea tree oil, Australian walnut oil, corn oil, oyster sauce, olive oil, avocado oil, camellia oil, castor oil, safflower oil, jojoba oil, Sunflower oil, almond oil, rapeseed oil, sesame oil, soybean oil, peanut oil, triglyceride, tricaprylin, glyceryl triisopalmitate, and the like.

As the ester oil, there are cetyl octanoate, hexyl laurate, isopropyl myristate, octyl palmitate, isocetyl stearate, isopropyl isostearate, octyl isopalmitate, oleic acid Oxime ester, cetyl ethylhexanoate, tris(2-ethylhexanoate), pentaerythritol tetrakis(2-ethylhexanoate), 2-ethylhexyl succinate, diethyl sebacate Wait.

Further, in the oil-based skin external preparation of the present invention, in addition to the above-mentioned essential components, the quality or amount of the effect of the present invention may be substantially not impaired. In the inside, a general component used in a skin external composition such as a cosmetic is prepared. Examples of the general component include surfactants, tackifiers, humectants, powders, alcohols, water-soluble polymers, oil-soluble polymers, film forming agents, resins, ultraviolet absorbers, and antiseptic agents other than the above. Agent, antibacterial agent, perfume, salt, antioxidant, pH adjuster, chelating agent, cooling agent, anti-inflammatory agent, beauty component (whitening agent, cell activator, skin roughness improver, blood flow promoter, skin Astringents, anti-lipids, etc.), vitamins, amino acids, nucleic acids, hormones, inclusion compounds, and the like.

The submerged oil type skin external preparation of the present invention is not particularly limited, and it is preferred that the amount of the oil phase component is set to be about 20% by mass or less. Here, the oil phase component refers to a component which is mixed as an oily phase and is emulsified in an aqueous phase in the case of producing an oily skin external preparation in water, and specifically includes an oil-soluble preservative, in addition to the above oil component, An oil-soluble ultraviolet absorber, an oil-soluble agent, an oily antioxidant, an oily fragrance, or the like. When the oil phase component is more than 20% by mass, it becomes greasy in terms of the feeling of use, and it is also sticky, which is not preferable.

<Method for producing oil-based skin external preparation>

The oily oil type skin external preparation of the present invention can be produced by a method for producing an emulsion composition which is usually used. Specifically, the water phase component and the oil phase component are each mixed at the same temperature, and the oil phase is added to the water phase while stirring, and the mixture is dispersed and emulsified, and is appropriately cooled and produced.

<Form of water-based skin external preparation>

The oil-based skin external preparation of the present invention can be used for moisturizing cream, serum, etc. Skin care cosmetics, sunscreens, body lotions, and other body care cosmetics, etc. may be used in all skin cosmetics.

[Examples]

Hereinafter, the present invention will be described in further detail based on examples, but the present invention is not limited to the following examples. Further, the blending amount is expressed by mass% relative to the total weight of the oily skin external preparation in water.

Before describing the embodiment, the evaluation methods employed in the respective embodiments will be described.

[Useability evaluation (thickness)]

0.5 g of each of the oil-based skin external preparations of the respective Examples and Comparative Examples was applied to the palm of the hand and spread on the face, and the sensory evaluation at this time was carried out based on the following criteria.

○: I feel very thick

△: Although there is a thick feeling, it does not feel enough.

×: I didn't feel thick, I was thinner when I first started applying it.

[Evaluation of stability over time]

The samples obtained in the examples and the comparative examples were stored at 0 ° C, room temperature (25 ° C), and 37 ° C for 2 weeks, and visually observed whether or not the slurry was generated, and evaluated based on the following evaluation criteria.

(Evaluation)

○: No slurry was observed in all the samples tested.

△: Separation was observed in one of the samples.

×: Separation was observed in all the samples tested.

(Examples 1 to 2 and Comparative Examples 1 to 7)

An aqueous oily skin external preparation having the composition shown in Table 1 below was prepared. Using this as a sample, the usability and the stability with time were evaluated in accordance with the above evaluation criteria. The results are shown together in Table 1.

(method of law)

The oil phase parts ((7) to (18)) and the water phase parts ((1) to (6) and (19) to (21)) are completely dissolved at 70 ° C, and the oil phase portion is added to the water phase. The mixture was stirred and emulsified at 70 ° C, and then the emulsified particle size was adjusted at 65 ° C using a homomixer, and cooled to room temperature to obtain a cream.

As is clear from the results shown in Table 1, all of the oil-in-water type containing high molecular weight polyethylene glycol, higher alcohol, sodium N-stearyl sulfonyl-N-methyl taurate, and nonionic surfactant The external preparation for skin (Example 1) showed excellent results in terms of thick feeling and temporal stability at a wide range of ambient temperatures from low temperature to high temperature. This result was the same even in the case where the three-scented gum as the viscosity-increasing stabilizer was not completely blended (Example 2).

On the other hand, it was confirmed that the case of containing no N-stearyl sulfhydryl-N-methyltaurine sodium (Comparative Example 1) and N-stearyl fluorenyl-N-A was not contained as compared with Example 1. Sodium taurosulfonate instead of nonionic surfactant (Comparative Examples 2 to 4), and sodium N-stearyl sulfonyl-N-methyltaurate but no nonionic interfacial activity In the case of the agent (Comparative Example 5), although the feeling of richness was sufficient, the stability with time was deteriorated.

Further, it can be reconfirmed that if polyethylene glycol 20000 is not formulated in the oily skin external preparation, a sufficient thick feeling cannot be obtained (Comparative Example 6), and even if polyethylene glycol 20000 is blended, When the amount of the three-scented gum of the viscosity-increasing stabilizer is too large, the stickiness becomes remarkable, and the usability is impaired (Comparative Example 7).

(Example 3 and Comparative Examples 8 to 10)

An oil-in-water type skin external preparation having the composition shown in the following Table 2 was prepared in the same manner as above, and this was used as a sample, and the usability and the stability over time were evaluated in accordance with the above evaluation criteria. The results are shown together in Table 2.

From the results shown in Table 2, it was clearly confirmed that even if N-stearyl-N-methyltaurate was replaced, an equivalent amount of sodium palmitoyl methyltaurate having a structure similar thereto was formulated. (Comparative Example 8), sodium cocoyl methyl taurate (Comparative Example 9), sodium laurate methyl taurate (Comparative Example 10), and sufficient stability with time was not obtained.

(Examples 4 to 5 and Comparative Example 11)

An oil-in-water type skin external preparation having the composition shown in Table 3 below was prepared in the same manner as above, and was used as a sample according to the above evaluation criteria. Evaluation of lineability and stability over time. The results are shown together in Table 3.

From the results shown in Table 3, it was confirmed that if the amount of N-stearyl-N-methyltaurate was too large, N-stearyl-N-methyl taurate was produced. It is sticky and detrimental to usability.

(Example 6: skin cream)

Production method:

The oil phase portion ((7) to (16)) and the water phase portion ((1) to (6) and (17) to (19)) are completely dissolved at 70 ° C, and the oil phase portion is added to the water phase. The mixture was stirred and emulsified at 70 ° C, and then the emulsified particle size was adjusted at 65 ° C using a homomixer, and cooled to room temperature to obtain a cream.

The cream was evaluated in the same manner as above, and as a result, it was confirmed that it was sufficiently thick when applied to the skin, and was excellent in stability over time.

(Example 7: Blending a cream with agar microcapsules)

Production method:

The oil phase parts ((8) to (20)) and the water phase parts ((1) to (6) and (21) to (23)) are completely dissolved at 70 ° C, and the oil phase portion is added to the water phase. The mixture was stirred and emulsified at 70 ° C, and the agar microcapsule portion (7) prepared in another manner was added thereto and emulsified at 70 ° C. Thereafter, the emulsified particle size was carried out at 65 ° C using a homomixer. Adjust and cool to room temperature to obtain a cream.

The cream was evaluated in the same manner as above, and as a result, it was confirmed that it was sufficiently thick when applied to the skin, and was excellent in stability over time.

(Example 8: Skin cream without using a tackifier)

Production method:

The oil phase portion ((6) to (15)) and the water phase portion ((1) to (5) and (16) to (18)) are completely dissolved at 70 ° C, and the oil phase portion is added to the water phase. The mixture was stirred and emulsified at 70 ° C, and then the emulsified particle size was adjusted at 65 ° C using a homomixer, and cooled to room temperature to obtain a cream.

The cream was evaluated in the same manner as above, and as a result, it was confirmed that it was sufficiently thick when applied to the skin, and was excellent in stability over time.

Claims (3)

An oily skin external preparation containing (a) a high molecular weight polyethylene glycol, (b) a higher alcohol, and (c) less than 2.0% by mass of N-stearone-N-methyl taurate And (d) a nonionic surfactant. The submerged oil type skin external preparation according to claim 1, wherein (a) the high molecular weight polyethylene glycol is polyethylene glycol 20000. The submerged oil type skin external preparation according to claim 1 or 2, which comprises (d) a nonionic surfactant in an amount of from 1.0 to 10.0% by mass based on the total amount of the oily skin external preparation in water.