JP3197651B2 - Skin cosmetics - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a skin cosmetic composition which is excellent in skin safety, has an effect of rapidly lightening dark-skinned skin, and an effect of increasing the turnover speed of the stratum corneum, and has an excellent feeling in use. .

[0002]

2. Description of the Related Art Ultraviolet rays cause inflammation (erythema) on the skin and release various factors to stimulate melanocytes. As a result, the color tone changes and blackens. This darkening is due to overproduction of melanin, which is produced in melanocytes and passed to epidermal cells, and is produced by oxidation of tyrosine.

[0003] Conventionally, in order to prevent skin darkening, spots and freckles and to maintain the original white skin, vitamin C salts and fatty acid derivatives that prevent this oxidation, as well as hydroquinone monobenzyl ether, hydrogen peroxide, etc., are blended. Skin cosmetics have been proposed.

However, when a vitamin C derivative is added to these whitening cosmetics, the storage stability is often insufficient, or the effect of suppressing inflammation and whitening by ultraviolet rays is often not sufficiently recognized. On the other hand, when hydroquinone monobenzyl ether or the like is blended in a whitening cosmetic, it has the effect of lightening dark-skinned skin, but has drawbacks such as a problem in skin safety. As described above, it is extremely difficult to obtain a whitening cosmetic having an excellent anti-inflammatory effect and a whitening effect and having high skin safety.

Further, when diisopropylamine dichloroacetate alone is blended, it has an effect of increasing the turnover speed of the stratum corneum, but its whitening effect is not satisfactory.

It has also been confirmed that glabridine, which is a hydrophobic component of licorice, alone has an antibacterial, antioxidant, anti-antibiotic, antiplasmin, and melanin-suppressing action. However, although the whitening effect was excellent, the feeling of use was not satisfactory.

[0007]

Means for Solving the Problems In view of such circumstances, the present inventors have conducted intensive studies to improve the disadvantages of the prior art, and as a result, the invention described later has a remarkably excellent whitening effect by synergism. The present inventors have found that it has an effect of enhancing the turnover speed of the stratum corneum, has high skin safety, and is excellent in a feeling of use, and has completed the present invention.

[0008] That is, an object of the present invention is to provide a skin cosmetic composition which is excellent in whitening effect, has high skin safety, and has an effect of enhancing the turnover speed of the stratum corneum and has an excellent feeling in use. It is.

In order to achieve the above object, the skin cosmetic of the present invention has the following constitution. That is, the present invention is a skin cosmetic comprising 0.001 to 1.0% by weight of glabridine and 0.01 to 1.0% by weight of diisopropylamine dichloroacetate.

[0010] Diisopropylamine dichloroacetate (hereinafter abbreviated as DADA) used in the skin cosmetic of the present invention is a known compound, and JP-A-53-136528 describes that it has a skin tissue activating effect.

[0011] Glabridin used in the skin cosmetic of the present invention is naturally a kind of licorice, Glycyrrhiza glab.
a A trace amount is contained in Linne var. (commonly known as Russia, Afghanistan and Turkey licorice). As a method for producing grabradine, licorice root or a water-extraction residue thereof (for example, a residue obtained by extracting glycyrrhizin) is extracted with an organic solvent. Examples of the extraction solvent include lower aliphatic alcohols such as methanol and ethanol, lower aliphatic ketones such as acetone, ethers such as dioxane and ethyl ether, halogenated hydrocarbons such as methylene chloride, esters such as ethyl acetate, and hexane. One or a mixture of two or more organic solvents of hydrocarbons such as Liquorice to be extracted is about 5
It is immersed in about 15 times the amount of the above-mentioned solvent and left standing at room temperature or heated under reflux. The extract obtained by distilling off the solvent from the extract usually contains about 5 to 10% of glabridine. Purification can be performed, for example, by normal-phase silica gel column chromatography and reverse-phase silica gel column chromatography, and then a pure glabridine product can be obtained relatively easily by recrystallization from acetone. Purification can be performed by any other means for purifying organic compounds such as column chromatography using a synthetic adsorbent.

[0012] The amount of the skin lightening cosmetic composition of the present invention of Glabridin, based on the total amount, 0. 001-1.0
% By weight (hereinafter referred to as wt%).

[0013] The amount of the skin cosmetic of the present invention DADA, on a dry solid amount, based on the total amount, 0. 01 ~
1.0 wt%.

If the amount of glabridine is less than 0.001% by weight and DADA is 0.01% by weight, the effect of the present invention is not sufficient. Even if the amount of glabridine and DADA exceeds 3.0% by weight, respectively. , The improvement of the effect corresponding to the increase cannot be expected, and the feeling at the time of use is likely to deteriorate,
It becomes difficult to hold individual dosage forms.

The whitening cosmetic composition of the present invention can be made into dosage forms such as lotions, emulsions, creams, packs and the like according to a conventional method.

The whitening cosmetic composition of the present invention may be appropriately blended with pigments, fragrances, preservatives, surfactants, pigments and the like within a range that achieves the object of the present invention.

[0017]

The present invention will be described below in detail based on examples and comparative examples.

(1) Tyrosinase activity inhibition test (2) Skin color brightness recovery test (3) Whitening practical test (4) Stratum corneum turnover speed measurement test (5) Optical patch test (6) Sensory Each test method is as follows.

(1) Tyrosinase activity inhibition test 0.3 m per 1 ml of McClubine buffer (pH 6.8)
The sample solution of each concentration is added to the tyrosine solution having a concentration of g / ml, and preliminarily kept at 37 ° C. for 10 minutes. 1m to this
0.1 ml of tyrosinase (manufactured by Sigma) at a concentration of g / ml
After heating at 37 ° C. for 15 minutes, the absorbance (A) was measured at a wavelength of 475 nm using a spectrophotometer. On the other hand, the absorbance (B) obtained by adding 0.1 ml of buffer solution instead of tyrosinase,
The absorbance (C) of the solution to which the solution had been added and the absorbance (D) of the solution to which 0.2 ml of the buffer had been added instead of the sample solution and tyrosinase were measured, and the inhibition rate (%) was calculated according to the following formula.

Inhibition rate (%) = ｛1- (AB) / (C−
D)｝ × 100

(2) Skin lightness recovery test The skin of the upper inner arm of the 20 test subjects was continuously irradiated with the minimum amount of UVA and UVB erythema in the UVA and UVB regions for 3 days. After the irradiation was completed, the sample application section and the base application section were applied. Reference lightness of skin (V0
(V0 'value) was measured. Subsequently, the composition was applied three times a day for four consecutive weeks, and the skin lightness (Vn value, Vn ′) of the sample-applied part and the base-applied part at 1, 2, and 4 weeks after the start of irradiation
Was measured, and the skin color was evaluated for recovery according to the following criteria.

The lightness of the skin (V value of Munsell display system) was obtained by measuring with a high-speed spectral colorimeter and calculated from the X, Y and Z values. The evaluation was shown as an average of the evaluation points of the 20 test subjects after 4 weeks.

[0023]

[Table 1]

(3) Practical skin whitening test The left forearm flexing side skin of 20 test subject's forearm flexing side skin exposed to sunlight in summer for 3 hours (1.5 hours a day for 2 days). From the day of sun exposure to the skin,
The base was applied to the right forearm flexion side skin once a day in the morning and evening for 13 weeks from the day of exposure to sunlight.

The evaluation was made based on the number of subjects who confirmed the effect of the sample application section from the base application section.

(4) Measurement test of the turnover speed of the stratum corneum Twenty test subjects were irradiated once with 1.5 MED UVB at two sites on the flexion side of the forearm, and three days later, dansyl chloride, a fluorescent dye, was placed in white petrolatum. Ointment mixed with 5% by weight is applied to the irradiated skin for 24 hours, and dansyl chloride is penetrated into the stratum corneum. Then, three times a day (morning,
(After noon, after bathing) The sample and the base were applied, and the fluorescence of dansyl chloride was examined every day. The number of days until the fluorescence disappeared was determined, and the result was defined as the turnover speed of the stratum corneum of the skin. still,
The normal skin stratum corneum turnover rate is 14-16 days.

(5) Optical Patch Test Closed patching was performed for 24 hours using a 1.0 cm diameter patch plate on which 0.05 g of a sample was applied to the skin of the flexed side of the forearm of 25 subjects. 6 hours (3 days a day)
Irradiation for 2 days).

The evaluation was performed according to the following criteria.
The skin condition of five persons was evaluated and evaluated. The judgment result is irradiation 2
Four hours later, the number was indicated by (±) or more.

[0029]

[Table 2]

(6) Sensory Test Twenty test subjects evaluated the characteristics of the sample after continuously using the sample for 10 days.

The evaluation was based on the number of respondents who answered that "skin was moistened", "skin affinity was good", and "skin gloss was improved" in response to questionnaire items such as wettability and affinity. Indicated.

Examples 1 to 3 and Comparative Examples 1 to 5 Two-phase lotion In the raw material composition shown in Table 3, active ingredients were blended as shown in Table 4 to prepare a two-phase lotion. Was carried out.

[0033]

[Table 3]

[0034]

[Table 4]

(1) Preparation method After the components B and C shown in Table 3 are uniformly dissolved in the component A and the component C is uniformly dissolved in the component D, the components A and D are uniformly mixed, stirred and dispersed, and then filled into a container. I do. When used, the contents are shaken and dispersed uniformly.

(2) Characteristics Table 4 shows the results of various tests. As shown in Table 4, Comparative Example 1 did not show good results in various tests.

The whitening cosmetics of the present invention of Examples 1 to 3 showed clearly good results in all tests and did not cause skin irritation in tests on human skin.

Examples 4 to 6 and Comparative Examples 6 to 10 Skin Cream In the raw material composition shown in Table 5, active ingredients were blended as shown in Table 6 to prepare a skin cream, and the above-mentioned tests were carried out.

[0039]

[Table 5]

[0040]

[Table 6]

(1) Preparation method The B component described in Table 5 is mixed with the A component, and the C component is uniformly heated and dissolved in the D component to bring the temperature to 80 ° C. Next, after injecting and emulsifying the D component in the A component, the mixture is cooled to 30 ° C. while stirring.

Table 6 shows the results of the tests. As shown in Table 6, Examples 4 to 6 showed clearly good results in all tests, good results in tests on human skin, and skin irritation in tests on human skin. Did not occur.

As described above, the present invention has an effect of suppressing the production of melanin pigment, an effect of rapidly lightening skin pigmentation, and an effect of increasing the turnover speed of the stratum corneum.
It is clear that a skin cosmetic composition which is free from skin irritation and has an excellent feeling upon use is provided.

Continuation of front page (56) References JP-A-1-3111011 (JP, A) JP-A-2-138108 (JP, A) JP-A-64-42414 (JP, A) JP-A-62-96405 (JP, A) JP-A-62-72605 (JP, A) JP-A-61-207312 (JP, A) JP-A-62-96404 (JP, A) JP-A-62-51607 (JP, A) (58) Field surveyed (Int. Cl. ⁷ , DB name) A61K ^7/ 00-7/50 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] 1. A diisopropylamine dichloroacetate 0.01-1.0 % by weight and glabridine 0.001-0.001.
1. A skin cosmetic comprising 1.0% by weight .