JPH09278640A - Cosmetic for preventing ageing of skin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cosmetic for preventing the ageing of skin, excellent in ageing-preventing effects (a roughened skin-improving effect, a keratin- improving effect, an effect for increasing a turn-over speed) and a skin- beautifying effect. SOLUTION: This cosmetic for preventing the ageing of skin contains (a) one or more kinds of mevalonic acid and mevalonic acid lactone and (b) one or more kinds of diisopropylamine dichloroacetate, urea and a 2-28C α- hydroxycarboxylic acid compound.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a skin anti-aging cosmetic composition, and more specifically, it exhibits an excellent anti-aging effect (effect of improving rough skin, effect of improving keratin, effect of accelerating turnover speed) and beautiful skin effect. The present invention relates to a skin anti-aging cosmetic excellent in application.

[0002]

2. Description of the Related Art Aged skin becomes rough and dry without smoothness, and keratinocyte exfoliation is observed. Aged skin has a slow turnover speed, and it is said that the turnover speed of the skin increases when the antiaging effect is developed and imparted to the skin. Conventionally, various cosmetics that impart a suitable moist feeling and flexibility to the skin surface have been proposed. For example, in Japanese Patent Application Laid-Open No. 4-99707, R-
(-) Skin cosmetics containing mevalonic acid have been proposed. However, although these skin cosmetics act on the epidermis of the skin tissue, they also rarely act on the dermis, which is the tissue under the epidermis, and therefore, the effect of merely imparting a moist feeling to the skin and flexibility. Although it can be expected, it does not have a sufficient effect of preventing skin aging.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to provide a skin anti-aging cosmetic which exerts and imparts an anti-aging effect (effect of improving rough skin, effect of improving keratin, effect of accelerating turnover speed) and beautiful skin effect. To provide.

[0004]

Means for Solving the Problems The above-mentioned objects are (a) one or more kinds selected from mevalonic acid and mevalonic acid lactone, and (b) diisopropylamine dichloroacetate,
This is achieved by a skin antiaging cosmetic composition containing urea and one or more selected from the group consisting of α-hydroxycarboxylic acid compounds having 2 to 28 carbon atoms.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The mevalonic acid used as the component (a) in the present invention is also referred to as pyroclastic acid (molecular formula: C ₆ H ₁₂ O ₄ ), and true fire bacterium (Lactobacillus) mixed in sake.
lulus homeochichi and L. et al. hetero
chichi), and lactic acid bacteria (L. a.
Cidophilus), a substance found as a growth-promoting factor, and is used as a biosynthesis precursor for isoprenoid compounds such as sterols, or as a raw material for chemically or enzymatically synthesizing various optically active substances. Mevalonic acid has two isomers [R (-)-mevalonic acid, S (+)
-Mevalonic acid], and naturally-occurring R (-)-
Although any of mevalonic acid can be used in the present invention, R (−)-mevalonic acid, which is easily available, is preferable.
R (-)-mevalonic acid is described, for example, in JP-A-63-216.
No. 484, No. 63-216485, No. 63-216486, No. 63-21648.
It can be produced by the microbial fermentation method described in Japanese Patent No. 7 or the like. Alternatively, it can be produced as a racemate (mixture of isomers) by a chemical synthesis method, and can be isolated and used as each isomer. Further, in the present invention (a)
Mevalonic acid lactone (molecular formula: C ₆ H ₁₀ O ₃ ) which is a derivative of mevalonic acid used as a component is a compound having a property of being easily converted into mevalonic acid by hydrolysis.

On the other hand, the component (b) used in the present invention is a compound known as a skin activating agent, and is diisopropylamine dichloroacetate (hereinafter referred to as DAD).
Abbreviated as A. ) Is proposed in JP-A-53-136528 for incorporation into skin cosmetics. Urea is also a substance widely used in skin cosmetics as a skin tissue activating component. Further, an α-hydroxycarboxylic acid compound having 2 to 28 carbon atoms is also a substance used in skin cosmetics, and examples thereof include glycolic acid (α-hydroxyethanoic acid) and lactic acid (α-hydroxypropanoic acid). , Α-hydroxyhexanoic acid, α-hydroxyoctanoic acid, α-hydroxydecanoic acid, α-hydroxydodecanoic acid, α-hydroxyhexadecanoic acid, α-hydroxyoctadecanoic acid, α-hydroxyeicosanoic acid, α-hydroxydocosanoic acid , Α-hydroxyhexacosanoic acid, α-hydroxyoctacosanoic acid. Among the above α-hydroxycarboxylic acid compounds, particularly preferred are glycolic acid, lactic acid and α-hydroxyoctanoic acid.
The α-hydroxycarboxylic acid compound used in the present invention includes a salt compound in addition to the acid compound. And in this invention, these (b) components and
Beginning with the combined use of (a) component mevalonic acid and mevalonic acid lactone, the synergistic effects of the anti-aging effect (rough skin improving effect, keratin improving effect, effect of accelerating turnover speed), beautiful skin effect It is expressed and given in a short period of time.

In the skin anti-aging cosmetic composition of the present invention, the preferred compounding amount of one or more of (a) component mevalonic acid and mevalonic acid lactone is preferably 0.001 to 0.001 based on the total amount of the skin anti-aging cosmetic composition. 10% by weight (hereinafter,
Abbreviated as wt%. ), And particularly preferably 0.0
It is 1 to 2.0 wt%. The amount of one or more selected from the group consisting of component (b) diisopropylamine dichloroacetate, urea, and an α-hydroxycarboxylic acid compound having 2 to 28 carbon atoms is preferably 0.001 to 3.0.
%, and particularly preferably 0.01 to 2.0 wt.
%. Furthermore, the component (b) is
It is preferable that the amount is 0.1 to 10 times (weight).

The dosage form of the skin anti-aging cosmetic composition of the present invention is not particularly limited, and it is applied to a usual skin cosmetic dosage form such as cream, emulsion, lotion, ointment, powder and the like. can do. Further, the skin aging preventive cosmetic of the present invention comprises, as other components, an emulsifier, an oily substance, a humectant, a thickener, a fragrance, a preservative, an antioxidant, a coloring agent, etc. Can be appropriately blended.

[0009]

The present invention will be described below in detail based on examples and comparative examples. In the Examples, (1) the method for measuring the turnover speed of the stratum corneum, (2) the method for measuring the effect of improving rough skin, (3) the method for measuring the effect of improving stratum corneum, and (4) the sensory test are as follows. .

(1) Method for measuring turnover rate of stratum corneum 5 wt% of dansyl chloride, a fluorescent dye, in white petrolatum
% Ointment was prepared and occluded and applied to the skin of the forearm of 20 subjects for 24 hours, and dansyl chloride was osmotically bonded to the stratum corneum. Thereafter, the test sample was applied to the same site twice a day (morning and evening), and the fluorescence of dansyl chloride was examined every day.
The number of days until the fluorescence disappeared was defined as the skin stratum corneum turnover speed. The measurement results were shown as an average of the number of days for each subject. The normal skin stratum corneum turnover is 1
4-16 days, but extends around 18 days in aged skin. On the other hand, when the anti-aging effect appears, 12
It is shortened to around days.

(2) Method for measuring the effect of improving rough skin The effect of continuous application for 4 weeks was investigated for 20 middle-aged and elderly subjects who have rough skin on their lower legs. That is, a test sample is applied to the left lower leg test site of the subject twice a day (morning and evening),
The skin condition before and after the test was evaluated according to the criteria shown in Table 1 below. The lower leg on the right side was used as a control without applying the test sample.

[0012]

[Table 1]

Then, the judgment results of the test site before and after the test and the control site are compared, and when the skin dryness is improved by two stages or more (for example: + → −, ++ → ±), it is “effective” and improved by one stage. When the result is "slightly valid", when there is no change, it is considered "invalid". The test results are shown by the number of subjects who were “effective” and “somewhat effective”.

(3) Method for measuring the effect of improving keratin (increasing anti-peeling property of keratinocytes) Scotch tape (Nichiban Co., Ltd. Mending Tape) is adhered to the skin of the test area before and after the start of and the end of the rough skin improvement measurement test described above. When this is peeled off, the state of keratinocytes attached to the tape is examined in detail by a scanning electron microscope,
The stratum corneum exfoliating property was classified according to the criteria shown in Table 2 below, and the effect of improving the keratin was determined.

[0015]

[Table 2]

The judgment is "effective" when the difference between the evaluation points of the test site and the control site after continuous application for 4 weeks is 2 points or more, "slightly effective" when 1 point or more, and "slightly effective" when 0 points. "Invalid" The test results are shown by the number of subjects who were “effective” and “somewhat effective”.

(4) Sensory test (Beautiful skin effect) Female subjects who complain of rough skin, fine wrinkles, dry skin (35-35)
Test sample twice a day (morning, evening) for 20 persons 3
The coating was applied for 1 month, and the effect after 1, 2 and 3 months was evaluated.
In the test results, for each item of skin wettability, smoothness, and elasticity, the respondents answered that "skin was moistened", "skin became smooth", and "skin became taut" Indicated by the number of people.

Examples 1 to 5, Comparative Examples 1 to 6 (skin cream) (a) component mevalonic acid, mevalonic acid lactone, (b)
The components diisopropylamine dichloroacetate, urea and lactic acid were blended as shown in Table 4, each skin cream was prepared with the composition shown in Table 3, and the above-mentioned various experiments were carried out.

(1) Composition

[0020]

[Table 3]

(2) Preparation method The component (A) in Table 3 above was melted at 70 ° C, mixed with the component (B), and then heated to 78 ° C. Next, this was gradually added to the component (C) heated to 75 ° C. with stirring to carry out preliminary emulsification. After that, the mixture was placed in a homogenizer to completely emulsify, cooled to 50 ° C., component (D) was added, and cooled to 30 ° C. to prepare a skin cream. The R (-)-mevalonic acid lactone blended as the component (a) is considered to be present in the skin cream in equilibrium with R (-)-mevalonic acid.

(3) Characteristics Various tests were conducted on each of the obtained skin creams,
Tables 4 and 5 show the results.

[0023]

[Table 4]

[0024]

[Table 5]

As shown in Tables 4 and 5, the skin creams of Comparative Examples 1 to 6 containing (a) component mevalonic acid, mevalonic acid lactone and (b) component DADA, urea and lactic acid were not blended or were alone blended. Although sufficient effects cannot be obtained in various properties, (a) mevalonic acid and mevalonic acid lactone,
The skin creams of Examples 1 to 5 in which the component (b), DADA, urea, and lactic acid were used in combination, were effective in improving rough skin, improving keratin, and increasing turnover speed, that is,
A remarkable effect was observed in the anti-aging effect of the skin, and a sensory test showed the effect of imparting wettability, smoothness and elasticity two months after application.

Example 6, Comparative Examples 7 to 9 (Skin Lotion) Each skin lotion was prepared according to the composition shown in Table 6 below, and various tests were conducted.

(1) Composition

[0028]

[Table 6]

(2) Preparation Method The ingredients in Table 6 above were stirred and uniformly dissolved to prepare a skin lotion. (3) Characteristics The skin lotion of Example 6 showed excellent skin beautiful effects and skin aging prevention effects (rough skin improvement effect, keratin improvement effect, and effect of accelerating turnover speed) as compared with Comparative Examples 7 to 9.

Example 7 (Skin Cream) A skin cream having the composition shown in Table 7 below was prepared.

[0031]

[Table 7]

(2) Preparation method The components (A) and (B) shown in Table 7 were uniformly heated and dissolved to bring the temperature to 80 ° C. Then, after injecting and emulsifying the component (B) in the component (A), the mixture is stirred at 30 ° C.
And cooled to prepare a skin cream.

Example 8 (skin milk) Skin milk having the composition shown in Table 8 below was prepared. (1) Composition

[0034]

[Table 8]

(2) Preparation method The components (A) and (B) shown in Table 8 were uniformly heated and dissolved to bring the temperature to 80 ° C. Then, after injecting and emulsifying the component (B) in the component (A), the mixture is stirred at 30 ° C.
And cooled to prepare a skin milk.

The skin creams and skin milks obtained in the above Examples 7 to 8 exhibited excellent skin aging prevention effects (rough skin improving effect, keratin improving effect, effect of accelerating turnover speed) and beautiful skin effect. .

[0037]

Industrial Applicability As described above, the present invention provides a skin anti-aging cosmetic excellent in skin anti-aging effect (rough skin improving effect, keratin improving effect, effect of increasing turnover speed) and skin beautiful effect. Is clear.

Claims (1)

[Claims] 1. A compound selected from the group consisting of (a) one or more selected from mevalonic acid and lactone mevalonic acid, and (b) diisopropylamine dichloroacetate, urea, and an α-hydroxycarboxylic acid compound having 2 to 28 carbon atoms. A cosmetic for preventing skin aging, which comprises one or more kinds of ingredients.