JPH08310941A - Oil-in-water emulsion cosmetics for sunscreen - Google Patents

Abstract

(57) [Abstract] [Purpose] A sunscreen oil-in-water emulsion cosmetic that does not use a hydrophilic surfactant, is mildly acidic, has low skin irritation, high water resistance, and long-lasting makeup. obtain. [Structure] 1 selected from (A) higher fatty acid, (B) higher alcohol, (C) fatty acid monoglyceride, monoalkyl glyceryl ether and monoalkenyl glyceryl ether
1 or 2 or more, (D) an ultraviolet absorber and / or (E) 1 or 2 or more selected from titanium oxide, zinc oxide and zirconium oxide, and the pH is 5.0 to 7.0. . The higher fatty acid (A) is preferably a fatty acid having 11 to 22 carbon atoms, and the higher alcohol (B) is 1 carbon atom.
Those having 2 to 22 aliphatic hydrocarbon chains are preferable.
Further, (A) / (B) is preferably 0.1 to 1.0, and [(A) + (B)] / (C) is preferably 1 to 10. As a result, it has extremely low irritation to the skin, excellent water resistance and long-lasting makeup,
It is possible to obtain the above-mentioned cosmetic which is fine, uniform and stable.

Description

Detailed Description of the Invention

[0001]

INDUSTRIAL APPLICABILITY The present invention does not contain a hydrophilic surfactant, is weakly acidic and safe for the skin, has a good feeling in use, and has high water resistance and long-lasting makeup. Relates to a sunscreen oil-in-water type emulsified cosmetic composition. More specifically, one or more selected from (A) higher fatty acids, (B) higher alcohols and (C) fatty acid monoglycerides, monoalkyl glyceryl ethers and monoalkenyl glyceryl ethers are blended in a specific weight ratio, Further, (D) an ultraviolet absorber and / or (E) one or more kinds selected from titanium oxide, zinc oxide and zirconium oxide are blended, and sunscreen water containing no other hydrophilic surfactant. A medium oil type emulsion cosmetic is provided.

[0002]

2. Description of the Related Art Conventionally, a lot of sunscreen cosmetics have been provided in order to prevent skin inflammation caused by ultraviolet rays. Among them, emulsion type dosage forms such as emulsion and cream are often used. In particular, the oil-in-water emulsion cosmetic has a moist and non-greasy feeling in use and is preferable as a sunscreen cosmetic. Such an oil-in-water emulsion composition is usually stably prepared with a fatty acid soap and various hydrophilic surfactants. Further, in recent years, in order to obtain an emulsified composition that is mild to the skin, there is a tendency that a weakly acidic one having a pH close to the skin surface is preferred.

However, when a fatty acid soap is used, a weakly acidic emulsion composition cannot be obtained, and on the other hand, the irritation of the skin to the skin and the irritation of the eye mucosa pose a problem. Therefore, attempts have been made to reduce the blending amount of them as much as possible, and surfactants having different HLB values are combined little by little, an emulsification aid such as a higher alcohol is blended, and it is not a general surfactant. A method of supplementarily adding a substance having an amphipathic property has been studied. In JP-A-5-262619, two higher alcohols having 18 or more carbon atoms are combined and blended, and in JP-A-53-113787, JP-A-55-59106, JP-A-56-154408 and JP-A-4-15289. Is α-monoalkyl glyceryl ether and other α, β
An amphipathic substance such as a diol compound having a hydroxyl group at the position, a long-chain acyl acidic amino acid or a salt thereof,
It is blended in combination with higher fatty acid salts and hydrophilic surfactants.

Higher alcohols form a lamellar liquid crystal or gel structure together with a surfactant in the continuous phase of an oil-in-water emulsion composition, and stabilize dispersed oil droplets. The presence of an activator is essential. Further, the monoalkyl glyceryl ether used in the above-mentioned invention is an amphipathic substance but has a strong lipophilicity, and this alone does not have sufficient surface activity. It was currently used as a drug. Further, even when a higher alcohol was used in combination, the oil droplets could not be sufficiently dispersed and stabilized. Only an attempt to prepare an emulsion composition by using a special branched glyceryl ether such as α-mono (methyl branched alkyl) glyceryl ether as the monoalkyl glyceryl ether has been made (JP-A-56-39033).

Further, since sunscreen cosmetics are mainly used outdoors during summer when the temperature and humidity are high, it is particularly required that the sunscreen cosmetics be resistant to sweat and water. However, in an oil-in-water type emulsion cosmetic using a hydrophilic surfactant, sufficient water resistance could not be obtained. Attempts have been made to improve the water resistance of the cosmetic film produced by adding a film-forming agent such as a water-insoluble silicone resin, but in this case, the film feels strong and it is difficult to obtain a natural finish. On the other hand, by using a water-in-oil type emulsion system, the water resistance is improved, but on the contrary, the elongation is heavy,
It was sticky to use, and it was difficult to secure stability over time.

[0006]

Therefore, the present invention solves the problems in the conventional emulsified cosmetics for sunscreen as described above, and is excellent in storage stability without the addition of a hydrophilic surfactant. It is intended to provide an oil-in-water type sunscreen cosmetic for sunscreen, which has a good acidity, is weakly acidic, has low irritation to the skin, and has a good appearance and feeling of use, a sufficient UV absorbing effect, and makeup lasting. is there.

[0007]

[Means for Solving the Problems] As a result of various investigations for solving the above problems, the present inventors have found that one selected from the conventionally used fatty acid monoglyceride, monoalkyl glyceryl ether and monoalkenyl glyceryl ether. Alternatively, an ultraviolet absorber or an ultraviolet scattering agent such as titanium oxide, zinc oxide or zirconium oxide is added to a base formed by combining two or more kinds and a higher fatty acid and a higher alcohol in a weight ratio within a certain range. By
The inventors have found that a stable, weakly acidic oil-in-water type emulsion cosmetic for sunscreen can be obtained without using a general hydrophilic surfactant, and have completed the present invention.

That is, in the present invention, one or more of (A) higher fatty acid, (B) higher alcohol, (C) fatty acid monoglyceride, monoalkyl glyceryl ether and monoalkenyl glyceryl ether, and (D) ultraviolet absorber And / or (E) one or more selected from titanium oxide, zinc oxide and zirconium oxide as an essential component, and water and oil are added thereto to form an oil-in-water emulsion cosmetic for sunscreen.

Examples of the higher fatty acid (A) include straight chain saturated fatty acids such as undecyl acid, lauric acid, tridecyl acid, myristic acid, pentadecyl acid, palmitic acid, heptadecyl acid, stearic acid, nonadecanoic acid, arachidic acid and behenic acid. Straight chain unsaturated fatty acids such as undecylenic acid, oleic acid, elaidic acid, cetrainic acid, erucic acid, linoleic acid and linolenic acid, branched chain fatty acids such as isomyristic acid, isopalmitic acid and isostearic acid, 12-hydroxy fatty acid, etc. And a mixture of higher fatty acids such as lanolin fatty acid, and the like, and those having 11 to 22 carbon atoms are particularly preferable.

Examples of the higher alcohol (B) include lauryl alcohol, tridecyl alcohol, myristyl alcohol, pentadecyl alcohol, cetyl alcohol, heptadecyl alcohol, stearyl alcohol, straight-chain aliphatic saturated alcohols, oleyl alcohol, linoleyl alcohol, Examples include linear unsaturated fatty alcohols such as linolenyl alcohol, branched chain fatty alcohols such as hexyldecanol, isostearyl alcohol and octyldodecanol, and mixtures of higher aliphatic alcohols such as cetostearyl alcohol and lanolin alcohol. Especially, those having an aliphatic hydrocarbon chain having 12 to 22 carbon atoms are preferable.

Examples of the fatty acid monoglyceride (C) include glyceryl monomyristate, glyceryl monopalmitate, glyceryl monostearate, glyceryl monoisostearate, and glyceryl monooleate. Monoalkyl glyceryl ethers include monopalmityl glyceryl. Ether (chimyl alcohol), monostearyl glyceryl ether (batyl alcohol) and the like, and examples of monoalkenyl glyceryl ether include monooleyl glyceryl ether (ceracyl alcohol) and the like.

The composition of each of the above components suitable for obtaining a stable oil-in-water emulsion cosmetic is within the range of the shaded area in FIG. The compounding ratios of (A), (B) and (C) are approximately 5.3 to 45.1% by weight and 24.
7-80.7% by weight, and 10.0-50.0% by weight are suitable. Further, the weight ratio of (A) / (B) is 0.1 to 1.0.
And the weight ratio of the total amount of (A) and (B) to (C) [(A) +
It is particularly preferable that (B)] / (C) is 1-10.

Examples of the UV absorber (D) include para-aminobenzoic acid esters such as ethyl paraaminobenzoate and ethylhexyl paradimethylaminobenzoate, and mid-wavelength range ultraviolet rays such as sinoxate and paramethoxycinnamate esters such as ethylhexyl paramethoxycinnamate. (UVB)
Long wavelength ultraviolet (UVA) absorbers such as absorbers, dibenzoylmethanes such as 4-t-butyl-4′-methoxydibenzoylmethane, and oxybenzones such as 2-hydroxy-4-methoxybenzophenone can be used. .

Further, as the component (E), an ultraviolet scattering agent such as titanium oxide, zinc oxide or zirconium oxide can be blended. As these ultraviolet scattering agents, those in the form of fine particles or those which have been subjected to a hydrophobic treatment or the like can be used. The components (D) and (E) may be used alone or in combination.

In the oil-in-water type emulsion cosmetic for sunscreen according to the present invention, in addition to the higher fatty acid (A) and the higher alcohol (B), hydrocarbon oil such as squalane, liquid paraffin, isopropyl myristate, myristin Ester oils such as octyldodecyl acidate and isopropyl palmitate,
Vegetable oils such as avocado oil, olive oil, soybean oil and castor oil, animal oils such as mink oil and turtle oil, animal waxes such as beeswax and lanolin, vegetable waxes such as jojoba oil, carnauba wax and candelilla wax, dimethyl poly If it is a common oily material used for cosmetics, such as silicone oils such as siloxane and methylphenylpolysiloxane,
It can be used without particular limitation.

The pH of the oil-in-water emulsion cosmetic for sunscreen according to the present invention is as follows: buffer solution such as citrate buffer solution, basic substance such as potassium hydroxide, sodium hydroxide, arginine, sodium lactate, pyrrolidonecarboxylic acid. It can be adjusted using a salt of a weak acid such as sodium and a strong base. In order to reduce the irritation to the skin, the pH is preferably 5.0 to 7.0.

Further, the sunscreen oil-in-water type emulsion cosmetics according to the present invention include moisturizers such as polyhydric alcohols, sugars and amino acids, physiologically active ingredients such as vitamins, nucleic acids, animal and plant extracts, preservatives and pigments. Etc. can be blended as required.

The emulsified cosmetic composition for sunscreen according to the present invention is prepared by mixing the above components (A), (B), (C) and (D) with other oily components and heating them to obtain a uniform mixture. It can be obtained by dissolving the water-soluble component, adding it to a heated aqueous phase with stirring, and emulsifying it with an emulsifying machine such as a homomixer. The stability can be further improved by using a more powerful high pressure homogenizer or ultrasonic emulsifier. In addition,
About component (E), it is usually added to the aqueous phase and dispersed,
When a hydrophobized product is used, it is dispersed in the oil phase and added.

[0019]

In the oil-in-water type emulsion cosmetic for sunscreen according to the present invention, the oily component can be stably emulsified and a fine emulsion can be obtained without using a hydrophilic surfactant. Moreover, it has high water resistance, shows resistance to runoff due to water and sweat, and has excellent makeup durability. Therefore, the action of the ultraviolet absorber or the ultraviolet scattering powder contained in the cosmetic can be maintained for a long time. Also, with a good appearance peculiar to oil-in-water emulsion cosmetics,
A refreshing and refreshing feeling of use is obtained,
It can be applied thinly and uniformly. Furthermore, it is weakly acidic and has no skin irritation or sensitizing property derived from pH or surfactant.

[0020]

EXAMPLES The features of the present invention will be described in detail with reference to Examples.

First, the formulations of sunscreen emulsions according to Examples 1 and 2 of the present invention are shown in Tables 1 and 2 together with Comparative Examples 1 to 3 and Comparative Examples 4 to 6. .
In Table 1, (7), (8), and (10) were heated to 70 ° C. to mix and dissolve, and (6) was added and uniformly dispersed.
Mix in advance and heat to 80 ° C to homogenize (1) ~
(5) is added with stirring, and the mixture is stirred and emulsified with a homomixer at 70 ° C. After cooling, (9) is added to prepare. On the other hand, in Table 2, (6) is dispersed in the oil phase, and the others are similarly emulsified and prepared.

[Table 1]

[Table 2]

Regarding Example 1 and Example 2, the pH was measured and the emulsified state and the storage stability at 40 ° C. were observed. The results are summarized in Table 3.

[0023]

[Table 3] As is clear from Table 3, the sunscreen emulsion cosmetics of Example 1 and Example 2 have uniform and fine emulsion particles having a particle size of 1 to 10 μm and a pH of 6.2.
It was weakly acidic and was stable even when stored at 40 ° C for 1 month. On the other hand, Comparative Example 1 containing no stearic acid corresponding to the constituent component (A) of the present invention and the constituent component of the present invention
In Comparative Example 2 and Comparative Example 5 which did not contain glyceryl monostearate or monostearyl glyceryl ether corresponding to (C), an emulsion composition could not be obtained. Further, Comparative Example 3 in which the weight ratio (A) / (B) of the constituent component (A) and the constituent component (B) of the present invention is 3.0, stearyl alcohol corresponding to the constituent component (B) of the present invention Of Comparative Example 4 containing no C, and the weight ratio [(A) + (B)] / (C) of the component (A) and the component (B) of the present invention to the component (C) was 11.7. In Comparative Example 6, although the emulsified composition was obtained, the particle size of the emulsion was large at 10 μm or more, and was further non-uniform. The emulsion stability was poor, and creaming and separation of the oil phase were observed the day after preparation.

Next, the formulations of the sunscreen creams of Examples 3 and 4 of the present invention are shown in Tables 4 and 5 together with Comparative Examples 7 and 8, respectively. Here, Comparative Example 7 is an emulsion emulsified with a fatty acid soap and a nonionic surfactant, and Comparative Example 8 is an emulsion emulsified by using a hydrophilic surfactant and a lipophilic surfactant together.
In Table 4, the aqueous phases (7) to (9) and (11) were mixed and heated, and the powder of (6) was dispersed in this, and mixed and heated (1) to
Add the oil phase of (5), stir and emulsify at 70 ° C, and add (1
Prepare by adding the fragrance of 0). On the other hand, in Table 5, (8)
Is dispersed in the oil phase of (1) to (7), and is similarly emulsified to prepare.

[Table 4]

[Table 5]

With respect to the sunscreen creams of Examples 3 and 4, the skin irritation was evaluated together with Comparative Examples 7 and 8. Skin irritation is 30 for each sample
A closed patch test was conducted for 48 hours using a well-known panel and the results were evaluated according to the criteria shown in Table 6 and 3
The average value of the skin irritation index of 0 person is shown in Table 7 together with the pH value of each sample.

[Table 6]

[0026]

[Table 7] As is clear from Table 7, the cosmetic creams of Examples 3 and 4 of the present invention have pHs of 5.9 and 6.
0 was weakly acidic and the skin irritation index was a very low value of 0.05 and 0.06, respectively. On the other hand, Comparative Example 7, which was emulsified by using a fatty acid soap and a nonionic surfactant in combination, showed a slight alkalinity of 8.4 and a skin irritation index of 1.51, indicating a weak irritation. Further, in Comparative Example 8 emulsified using hydrophilic and lipophilic nonionic surfactants, the pH was 5.3, which was weakly acidic, but 2.
The skin irritation index was 72, which was close to a medium level, and some skin irritation was recognized.

Next, the water resistance of the oil-in-water type emulsion cosmetic for sunscreen according to the present invention was evaluated. Regarding Examples 1 to 4 of the present invention and Comparative Examples 7 and 8, first, the back portion was
It is applied to a portion of 20 square cm at a rate of mg / square cm and applied to a Sun Protection Factor (SP
F) was measured. After that, apply these samples to adjacent parts again and dry them sufficiently, and then perform underwater exercise such as swimming in the indoor pool for 20 minutes, and then perform a 20-minute underwater exercise again with a 20-minute break between them. Then, after drying without using a towel, the SPF was measured again. SPF
Is a xenon arc solar simulator as a light source, and uses 20 adult males of skin types I to III as subjects, and the minimum amount of erythema (ME
After obtaining D), irradiation above the expected SPF value of the sample is performed in 5 steps with a common ratio of 1.3, the MED of the sample application part is obtained, and the value of the sample application part is divided by the value of the sample non-application part. The SPF was calculated according to the average value of each subject. Table 8 shows the results.

[0028]

[Table 8] From Table 8, in each of the examples of the present invention, good water resistance was recognized, and a good SPF value was exhibited even after swimming or the like. On the other hand, in Comparative Example 7 and Comparative Example 8, since the sunscreen cosmetics that flowed due to underwater exercise such as swimming and remained on the skin decreased, S
The PF value was significantly reduced.

Next, the formulation of the oil-in-water type emulsion cosmetic for sunscreen according to the examples of the present invention will be shown below.

Example 5 Sunscreen Emulsion (for UVB Prevention) (1) Palmitic Acid 0.4 (wt%) (2) Cetyl Alcohol 1.5 (3) Lanolin Alcohol 2.0 (4) Vaseline 3 0.0 (5) Avocado oil 10.0 (6) Monopalmityl glyceryl ether 2.0 (7) Ethylhexyl paramethoxycinnamate 4.0 (8) Titanium oxide 8.0 (9) Glycerin 3.0 (10) Lactic acid Sodium 2.0 (11) Methyl paraoxybenzoate 0.1 (12) Perfume 0.1 (13) Purified water 63.9 Production method: (9) to (11) are dissolved in (13) and heated to 70 ° C. Then (8)
Was added and dispersed uniformly, and then mixed and dissolved in advance and heated to 80 ° C. (1) to (7)
Emulsify with a homomixer, cool and add (12) at 40 ° C.

Example 6 Sunscreen Emulsion (for UVA Prevention) (1) Myristic Acid 0.7 (wt%) (2) 12-Hydroxystearic Acid 0.5 (3) Oleyl Alcohol 5.0 (4) ) Behenyl alcohol 1.2 (5) Jojoba oil 15.0 (6) Monooleyl glyceryl ether 0.8 (7) Tocopherol acetate 0.5 (8) 4-t-butyl-4′-methoxydibenzoylmethane 6.0 (9) 1,3-Butanediol 5.0 (10) Arginine 2.0 (11) Methyl paraoxybenzoate 0.1 (12) Perfume 0.1 (13) Purified water 63.1 Process: (9) to (11) was dissolved in (13) and heated to 70 ° C, which was mixed and dissolved in advance and heated to 80 ° C (1) to
After adding (8), emulsify with a homomixer, cool and add (12) at 40 ° C.

[Example 7] Emulsion type lotion for sunscreen (for prevention of UVA and UVB) (1) Linoleic acid 0.5 (wt%) (2) Cetostearyl alcohol 5.0 (3) Squalane 10.0 ( 4) Vaseline 6.0 (5) Monostearyl glyceryl ether 0.8 (6) Glyceryl monooleate 0.2 (7) Tocopherol acetate 0.2 (8) Oxybenzone 2.0 (9) Ethylhexyl paramethoxycinnamate 2. 0 (10) Silicone treated zirconium oxide 5.0 (12) Propylene glycol 10.0 (13) Sodium citrate 3.0 (14) Methyl paraoxybenzoate 0.1 (15) Purified water 55.2 Manufacturing method: (12 )-(14) were dissolved in (15) and heated to 70 ° C, previously mixed, dissolved and heated to 80 ° C (1)
Add (10) to (9), add the dispersed substance, emulsify with a homomixer, and cool.

The sunscreen emulsions of Examples 5 and 6 and the sunscreen emulsion-type lotion of Example 7 all have uniform and fine emulsion particles having a particle size of 1 to 10 μm. It was stable for 1 month or longer when stored at 5 ° C and 40 ° C.

[0034]

As described in detail above, according to the present invention, a stable and good sunscreen oil-in-water emulsion cosmetic can be obtained without using a hydrophilic surfactant. Furthermore, the oil-in-water type emulsion cosmetic for sunscreen according to the present invention is weakly acidic, has extremely low irritation to the skin, has high water resistance, exhibits good resistance to sweat and water, and is hot and humid in the summer. Also, good makeup lasting is exhibited both during exercise and during exercise.

[Brief description of drawings]

FIG. 1 is a diagram showing an appropriate composition of constituent components (A), (B) and (C) in the present invention.

Claims (4)

[Claims] 1. (A) higher fatty acid, (B) higher alcohol,
(C) one or more selected from fatty acid monoglyceride, monoalkyl glyceryl ether and monoalkenyl glyceryl ether, (D) ultraviolet absorber and / or (E)
It contains one or more selected from titanium oxide, zinc oxide and zirconium oxide, and has a pH of 5.0 to 7.
An oil-in-water type emulsified cosmetic composition for sunscreen, which is characterized by being 0. 2. The higher fatty acid (A) has 11 to 22 carbon atoms.
The oil-in-water type emulsion cosmetic for sunscreen according to claim 1, which is a fatty acid of 3. The higher alcohol (B) has 12 to 12 carbon atoms.
The oil-in-water type emulsion cosmetic for sunscreen according to claim 1 or 2, which has 22 aliphatic hydrocarbon chains. 4. A higher fatty acid: higher alcohol weight ratio.
(A) / (B) is 0.1 to 1.0, and the total amount of higher fatty acid and higher alcohol, and one or more selected from fatty acid monoglyceride, monoalkyl glyceryl ether and monoalkenyl glyceryl ether. The oil-in-water type sunscreen sunscreen cosmetic composition according to claim 1, wherein the weight ratio [(A) + (B)] / (C) is 1 to 10.