JP2931703B2 - Cosmetics - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to cosmetics, and more particularly, to cosmetics which are excellent in moisturizing effect and skin roughening effect on skin, while having excellent protective effect on hair based on film forming action. It will not be provided.

[0002]

2. Description of the Related Art In general, drying of the skin depends on the amount of skin secretions,
In particular, it occurs when the barrier function of the stratum corneum is reduced due to a decrease in sebum secretion, and transepidermal water loss (hereinafter abbreviated as TEWL) increases. Therefore, a condition in which skin dryness worsens due to a decrease in skin secretions due to winter or excessive skin washing, age, constitution, and the like, and a condition in which the water content of the stratum corneum is reduced to about 10% or less is particularly called dry skin. As described above, when the skin is in a dry state, the gloss of the skin decreases, and adverse effects such as fine wrinkles appear. Similarly, a decrease in the amount of water in the hair causes the hair to lose its smoothness and to cause other problems such as a decrease in gloss.

Conventionally, in order to improve these skin conditions and hair conditions, it has been necessary to prevent a decrease in the water content of the stratum corneum and hair and to maintain a normal function. Has been studied. As a result, the proposed method has a good adhesiveness to the skin and a TE using a hydrophobic vaseline ointment or a water-in-oil emulsion.
A method for suppressing WL, having hygroscopicity and moisturizing power, for example, polysaccharides such as hyaluronic acid and chitin, proteins such as collagen and elastin, polyhydric alcohols such as sorbitol, ethylene glycol and glycerin, and pyrrolidone carboxylic acid There has been a method of enhancing the hydration effect by blending a moisture absorbent and a humectant such as organic acid salts such as soda and sodium lactate into a skin material base or a hair material base. Recently, it was revealed that ceramide and sphingolipids, which are components of intercellular lipids such as the stratum corneum, play an important role in retaining water, and ceramides from synthetic and natural extracts have also been added. It is getting.

[0004]

However, none of the above-mentioned methods known in the prior art has a sufficient water retention ability, and when an occlusive agent is used, they are greasy and sticky. On the other hand, in the case of using a moisture absorbent or a humectant, a large amount must be added in order to enhance the effect, and as a result, uncomfortable feelings such as sticky feeling and slimy feeling are obtained. There is a problem of giving a feeling, and further, there is a disadvantage of being inferior in stability over time and against microorganisms.

The present invention has been made in view of the above circumstances, and is intended to improve skin and hair conditions caused by dryness such as rough skin and lack of luster, and to provide moisturizing by sufficient moisture retention. It is an object of the present invention to provide a cosmetic composition having a beautiful hair effect and having almost no problem in feel.

[0006]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, the present inventors have found that the present inventors have found that the present inventors have found that the present invention has the same structure as a polar group of phospholipid (phosphatidylcholine), which is a main component of a biological membrane. Methacryloyloxyethyl phosphorylcholine is a copolymer having a constitutional unit is moisture-absorbing,
It has been found that the water retention function based on the moisturizing action is high, and that the adhesive action and the film forming ability are excellent, and based on this, the present invention has been completed.

That is, the present invention relates to a cosmetic comprising a copolymer of 2-methacryloyloxyethylphosphorylcholine and a hydrophobic monomer. In a preferred embodiment, the hydrophobic monomer is styrene or acrylic acid. At least one selected from esters and methacrylic esters, or the copolymer has a molecular weight of 5,000 or more, or the composition ratio of 2-methacryloyloxyethyl phosphorylcholine to the hydrophobic monomer is 3:97 to 4
5:55 or a cosmetic having a copolymer content of 0.001 to 10% by weight based on the total weight of the cosmetic.

Hereinafter, the present invention will be described in detail.

The copolymer applicable to the present invention is obtained by copolymerizing 2-methacryloyloxyethyl phosphorylcholine (hereinafter abbreviated as MPC) represented by the following general formula (I) with a hydrophobic monomer. It can be obtained by

[0010]

Embedded image

For such MPC, for example, 2-bromoethyl phosphoryl dichloride, 2-hydroxyethyl phosphoryl dichloride and 2-hydroxyethyl methacrylate are reacted to obtain 2-methacryloyloxyethyl-2'-bromoethyl phosphoric acid. This can be obtained by reacting with trimethylamine in a methanol solution. (Polymer Journal, Vol. 22, No. 5)

On the other hand, the hydrophobic monomers include MPC
And a vinyl copolymer to form a copolymer, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate,
Carboxyl groups such as acrylates or methacrylates, such as 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and 2-hydroxypropyl (meth) acrylate, acrylic acid, methacrylic acid, crotonic acid, and itaconic acid Monoethylenic monomers, styrene, vinyl chloride, acrylonitrile, acrylamide and the like can be mentioned. Among them, acrylic esters, methacrylic esters and styrene are preferable in terms of properties.

Next, the method for producing the copolymer may be a conventional method, and is obtained by reacting MPC and a hydrophobic monomer in a solvent in the presence of a polymerization initiator. The solvent used here may be any solvent in which MPC and the hydrophobic monomer are dissolved, and specifically, water, methanol, ethanol, propanol, t-butanol, benzene, toluene, dimethylformamide, tetrahydrofuran,
Chloroform or a mixed solvent thereof is exemplified.
As the polymerization initiator, any ordinary radical initiator may be used, and fatty acid azo compounds such as 2,2'-azobisisobutyronitrile (AIBN) and azobismalenonitrile, and benzoyl peroxide And organic peroxides such as lauroyl peroxide and potassium persulfate.

Hereinafter, production examples of the copolymer according to the present invention will be described. Production Example MPC / styrene copolymer MPC and styrene (St) were charged in a molar ratio of M
PC / St = 10/90, total monomer concentration is 1.0 mol /
l and an initiator concentration of 5 mmol / l.
544 g (12 mmol), St. 1.248 g (107.7)
mmol) was collected in a glass tube for polymerization, and 0.0985 g of AIBN was used as a polymerization initiator, and ethanol 2 was used as a solvent.
6.3 ml and tetrahydrofuran (THF) 81.3 ml
Was added. After replacing the inside of the reaction tube with argon, it was sealed.
This was heated at 60 ° C. for 16 hours to carry out a polymerization reaction. After cooling the reaction mixture on ice, the copolymer was precipitated by dropwise addition in 1.8 l of diethyl ether. This was separated by filtration, sufficiently washed with diethyl ether, and dried under reduced pressure to obtain 4.30 g of a white powdery copolymer. 〇IR (cm ^-1 ) measurement 3200 to 2900 (CH ₂ , CH ₃ ), 1720 (C
= 0) 1100-1200 (C-O-C), 1250 (P =
0) 〇 Molecular weight measurement The THF solution of the copolymer was analyzed and measured using GPC, and as a result, it was 37,000 in terms of polystyrene. Also,
From the determination of phosphorus, the MPC molar composition ratio in the copolymer was 13.
7%.

The molecular weight of the copolymer according to the present invention obtained as described above can be variously adjusted according to the purpose of use, but the molecular weight is considered in consideration of the touch surface, gelling ability, film forming ability and the like. Usually, it is 5,000 or more, preferably 10,000 or more, in terms of polystyrene. The composition ratio of MPC and hydrophobic monomer in the copolymer is preferably in the range of 3:97 to 45:55. That is, when the composition ratio of the MPC is less than 3:97, the water retention function and the adhesive action are undesirably reduced.

In the cosmetic of the present invention, the above-mentioned copolymer is usually contained in the range of 0.001 to 10% by weight, preferably 0.01 to 3% by weight, based on the total amount of the cosmetic.

Further, the cosmetic of the present invention comprises a lotion, an emulsion,
It can be used as a skin cosmetic in the form of creams, lipsticks, foundations, etc.
It can be used as a hair cosmetic in the form of a hair cream, a hair lotion or the like. Furthermore, it can be used as a massage charge or a pack charge by utilizing the gelling ability and the film forming ability of the copolymer. In addition, these cosmetics can be manufactured according to a conventional method.

Further, in the cosmetic of the present invention, in addition to the copolymer, a surfactant, a powder or a pigment, an antioxidant, an ultraviolet absorber, a humectant, a vitamin, a preservative, a fragrance may be added, if necessary. And the like.

Here, an experiment was conducted to evaluate how the copolymer according to the present invention has excellent moisture absorption properties and stability over time. The contents are shown below.

Experiment 1 Hygroscopicity of MPC / styrene copolymer [Sample] (A) MPC / styrene copolymer (constituent ratio 25/75,
(Molecular weight 12,000) (B) Chitosan (comparative product)

[Measurement Method] An ethanol solution of MPC / styrene copolymer (10 wt%) and an aqueous solution of chitosan in acetic acid (3 wt%) were prepared, and 5 ml of each solution was cast on a 25 cm ² Teflon plate. The solvent was evaporated to prepare a film having a thickness of about 100 μm. This was placed in a desiccator adjusted to each relative humidity (60%, 80%, 95%) with a saturated salt solution, and the weight increase rate after 20 hours or less and 20 hours or less was measured. The result is shown in FIG. Weight increase rate (%) = [(weight after 48 hours−initial weight)
/ Initial weight] x 100

[Results] As is apparent from the results shown in FIG. 1, the MPC / styrene copolymer according to the present invention has a higher hygroscopicity than the chitosan as a comparative product.

Experiment 2. Stability of MPC / styrene copolymer [Sample] MPC / styrene copolymer (constituent ratio: 20 /
80, molecular weight 15,000)

[Measurement method] PH4.
Each sample was dissolved at a concentration of 2% by weight in a 10% aqueous ethanol solution adjusted to 0, 6.0, 8.0, and 9.0, and 40%
It was left for 3 months at ℃ to observe its condition. At the start, no coloring or precipitation was observed, and the sample was transparent. Table 1 shows the results.

[0025]

[Table 1]

As shown in the results in Table 1, it was found that the MPC / styrene copolymer according to the present invention has excellent stability over time in a wide PH range.

[0027]

EXAMPLES Examples of the cosmetic of the present invention will be shown below.
The mixing ratio is% by weight.

Embodiment 1 o / w type emulsion stearic acid 1 beeswax 2 microcrystalline wax 1 MPC / n-butyl methacrylate copolymer 3% aqueous solution 30 (constituent ratio 15/85, molecular weight 35,000) propylene glycol 5 glycerin 2 ethyl alcohol 5 preservative 0 .3 Perfume 0.3 Purified water 53.4

Embodiment 2 Lotion MPC / styrene copolymer 2% aqueous solution 25 (10/82, molecular weight: 20,000) glycerin 1.5 ethanol 6 propylene glycol 1.5 citric acid 0.01 sodium citrate 0.1 fragrance 0.1 05 Purified water 65.84

Embodiment 3 Cream squalane 5 2-ethylhexanoic acid triglyceride 1 Vaseline 0.5 MPC / 2-hydroxymethyl methacrylate copolymer 3% aqueous solution (constituent ratio 18/82, molecular weight 20,000) 50 glycerin 3,1,3-butanediol 4 poly Glycerin polyoxybutylene stearyl ether 2.5 Fragrance 0.2 Purified water 33.8

Embodiment 4 Hair lotion MPC / methyl methacrylate copolymer 2% aqueous solution 5 (constituent ratio 35/65, molecular weight 45,000) Ethanol 10 Glycerin 3 Carboxymethylchitin 0.01 Vitamin E 0.1 Pigment 0.02 Purified water 81.87

Embodiment 5 FIG. Hair cream squalane 30.0 petrolatum 3.0 beeswax 4.0 stearic acid 4.0 olive oil 2.0 sorbitan monostearate 2.5 polyoxyethylene sorbitan monostearate 2.5 butyl paraben 0.1 MPC / ethyl acrylate 10% aqueous solution of polymer 30 (constitution ratio 35/65, molecular weight 40,000) 1,3-butanediol 2.5 polyethylene glycol 200 1.5 triethanolamine 1.0 methyl paraben 0.1 fragrance 0.2 purified water 16.6

(Comparative Experiment) The cosmetics obtained according to the present invention and conventional cosmetics were compared in terms of skin roughness improving effect and hair protecting effect.

Experiment 3 Effect of Improving Artificial Skin Roughness [Sample] (A) Emulsion of Example 1 of the present invention (A) MPC / n-butyl methacrylate copolymer was removed from the emulsion of Example 1 of the present invention (water was increased). Conventional emulsion

[Experiment method] 10 Japanese women (age 20-
The effect of the surfactant on the improvement of artificial skin roughness was measured by measuring the water content of the stratum corneum and judging skin eruption with a subject (age 37). That is, a glass cup having a diameter of 3 cm was adhered to the skin on the inner part of the forearm, 10 ml of 5% sodium dodecyl sulfate (SDS) was put therein, and the mixture was allowed to stand for 10 minutes while gently shaking. After leaving the same site for the next 20 minutes with the same processing solution, the processing solution was recovered to cause rough skin. This SD
One day after the S treatment, the emulsion of the sample (A) or (A) was applied to the treated site twice a day. FIGS. 2 and 3 show the results of measuring the horny layer water content before and after the experiment as skin surface conductance values according to the following measurement method, and the results (mean values) of skin rashes determined according to the following criteria.

1) Measurement of the water content of the stratum corneum The water content of the stratum corneum was determined according to the method of Tagami et al.
The measurement is performed using a ctance meter (Model IB-354, manufactured by IBM). At the time of measurement, the skin at the measurement site was 37 ° C.
After washing with warm water for 30 seconds, at 20 ° C and 50% relative humidity,
Five measurements are taken and the average is taken as the measured value.

2) Criteria for skin rash 0: No dry desquamation change is observed. 1: A slight drying desquamation change is recognized. (Faint desquamation or gloss) 2: A clear drying desquamation change is recognized. (The boundary of the treated part is clear, and clear desquamation is partially glossy and cracked.) (Clear luster, crack on clear desquamation)

As shown in the results of FIGS. 2 and 3, the sample (a), which is an emulsion of the product of the present invention, recovers the water content of the stratum corneum (compared to the sample (a), which is an emulsion of the conventional product). It has been demonstrated to have a remarkable effect on skin surface conductance) and dry eruption.

Experiment 4 Actual use test [Sample] The same emulsion as the samples (A) and (A) used in Experiment 3 was used.

[Experimental Method] Forty Japanese women (aged 20 to 49 years) who complain of rough and dry skin were randomly divided into groups A and B (20 each). The emulsion of the sample (a) was used, and the emulsion of the sample (a) was used for Group B for one month. A comparison was made between groups regarding the beautiful skin effect such as moist feeling (water retention effect) and improvement of skin swelling (activation effect) after one month and the feel during use (stickiness). Table 2 shows the results.

[0041]

[Table 2]

As is clear from the results shown in Table 2, the sample (A), which is an emulsion of the product of the present invention, has no tactile problem similarly to the sample (A) which is an emulsion of the conventional product, while the water retention effect is obtained. It has been proved that the skin beautiful effect such as skin activating effect and the like is remarkably excellent.

Experiment 5 Hair protection effect [Sample] (C) Hair lotion of Example 4 of the present invention (D) MPC from hair lotion of Example 4 of the present invention
/ Conventional hair lotion with removal of methyl methacrylate copolymer (increased water)

[Experimental Method] A bundle of 10 g (length 10 cm) of hair of a Japanese woman who had not been subjected to a treatment such as perm or bleach was bundled with a predetermined amount of the hair lotion of the sample (c) or (d). And then air-dried. The evaluation was performed by five expert panelists according to the criteria shown in Table 3 below, and the average score was shown in Table 4. The evaluation items were for hair smoothness, gloss and moist feeling (moisturizing property).

[0045]

[Table 3]

[0046]

[Table 4]

As shown in the results in Table 4, the sample (c), which is a hair lotion of the product of the present invention, has a smoothness, gloss and moistness of the hair which is higher than that of the sample (d) which is a hair lotion of the conventional product. It was clarified that all of the feelings were excellent.

[0048]

According to the present invention, not only is the skin beautiful effect on the skin based on the water retention function, adhesive action, film forming ability and the like, and also the hair beauty effect on the hair excellent, but also on stability. Can be used without any problems.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between relative humidity and weight increase rate.

FIG. 2 is a diagram showing a relationship between the number of days and a skin conductance value.

FIG. 3 is a diagram showing the relationship between the number of days and rash.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kazuhiko Ishihara 6-5-9-201, Josuihoncho, Kodaira-shi, Tokyo (72) Inventor Norio Nakabayashi 5-6-20, Koganehara, Matsudo-shi, Chiba (58) Field surveyed (Int.Cl. ⁶ , DB name) A61K 7/00-7/50

Claims (5)

(57) [Claims] 1. A cosmetic comprising a copolymer of 2-methacryloyloxyethyl phosphorylcholine and a hydrophobic monomer. 2. The cosmetic according to claim 1, wherein the hydrophobic monomer is at least one selected from styrene, acrylate, and methacrylate. 3. The cosmetic according to claim 1, wherein the molecular weight of the copolymer is 5,000 or more. 4. The cosmetic according to claim 1, wherein the composition ratio of 2-methacryloyloxyethyl phosphorylcholine to the hydrophobic monomer in the copolymer is from 3:97 to 45:55. 5. The content of the copolymer is based on the total amount of the cosmetic.
The cosmetic according to any one of claims 1 to 4, wherein the cosmetic content is 0.001 to 10% by weight.