JP2992416B2 - 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, the decrease in the amount of sebum secretion and the decrease in natural moisturizing factors such as intercellular lipids and amino acids cause the barrier function of the stratum corneum to decrease,
Occurs when 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 sodium pyrrolidone carboxylate 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 sodium lactate into a skin base or a hair 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 in fact, it is impossible to mix a large amount in a prescription system. Further, there is a disadvantage that the stability with respect to time and microorganisms is poor. Further, there is no compound which has a moisture absorbing and retaining action such as HA and a promoting and stabilizing action of an intercellular lipid lamellar layer such as ceramide, which assists the moisture absorbing and retaining function of the stratum corneum with one substance.

The present invention has been made in view of the above circumstances, and is intended to improve the condition of skin and hair 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,
The present inventors have found that they have a high moisture retention function based on a moisturizing effect, and are excellent in a lamellar formation promoting / stabilizing effect and a film forming ability, and based on this, the present invention has been completed.

That is, the present invention is a cosmetic comprising a copolymer of 2-methacryloyloxyethyl phosphorylcholine, a hydrophobic monomer and a hydrophilic monomer. As a preferred embodiment of the cosmetic of the present invention, as the hydrophobic monomer, for example, one or more selected from styrene, acrylic ester, methacrylic ester and the like can be mentioned, and as the hydrophilic monomer, a nonionic one can be used. For example, acrylamide, vinylpyrrolidone, polyethylene glycol monomethacrylate, 2-methacryloyloxyethylmethylsulfoxide and the like, and in the case of ionic ones, acrylic acid, methacrylic acid, acrylamide-2methyl-propanesulfonic acid, p-styrenesulfonic acid, One or more selected from 3-methacryloyloxypropyl sulfonic acid, N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, vinyl pyridine and the like can be mentioned. - As preferable ones nonionic. The molecular weight of the copolymer is preferably 5,000 or more. The composition ratio of 2-methacryloyloxyethyl phosphorylcholine, hydrophobic monomer, and hydrophilic monomer is 15 to 40:20 to 60:
Preferably, the content of the copolymer is from 20 to 60.
The content is preferably 0.001 to 10% by weight based on the total amount of the cosmetic.

Hereinafter, the present invention will be described in detail.

The copolymer applicable to the present invention comprises 2-methacryloyloxyethyl phosphorylcholine (hereinafter abbreviated as MPC) represented by the following general formula (I), a hydrophobic monomer and a hydrophilic monomer. Is obtained by copolymerizing

[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 Transactions, Vol. 35, pp. 423-42)
7, 1978)

As the hydrophobic monomer, MPC is used.
And a vinyl copolymer to form a copolymer, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate,
Examples include acrylate or methacrylate such as 2-ethylhexyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, and 2-hydroxypropyl (meth) acrylate, styrene, vinyl chloride, and acrylonitrile. Acid esters, methacrylic esters and styrene can be said to be preferable in terms of properties.

On the other hand, the non-ionic hydrophilic monomers include, for example, acrylamide, vinylpyrrolidone, polyethylene glycol monomethacrylate,
-Methacryloyloxyethyl methyl sulfoxide and the like and ionic ones, for example, acrylic acid,
Examples thereof include methacrylic acid, acrylamido-2-methyl-propanesulfonic acid, p-styrenesulfonic acid, 3-methacryloyloxypropylsulfonic acid, N, N-dimethylaminoethyl methacrylate, N, N-diethylaminoethyl methacrylate, and vinylpyridine. In particular, as the hydrophilic monomer, a nonionic one is preferable.

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

Hereinafter, production examples of the copolymer according to the present invention will be described.

[0016]MPC / polyethylene glycol (35
0) Monomethacrylate (PEM350) / n-butyl
Synthesis of methacrylate (BMA) copolymer MPC, PEM350 and BMA have a molar composition of 30
%, 25% and 45%, the total monomer concentration was 1 mol /
L, and dissolved in ethanol as an initiator.
0.6 mol% of BN is added to the monomer. Add solution
After placing in a Las reactor and thoroughly replacing with argon, seal the tube.
I do. The reaction was carried out at 60 ° C for 5 hours, and the reaction mixture was
The polymer is precipitated by dripping into ethyl ether. precipitation
Filter off the material and wash thoroughly with ether on a glass filter
After cleaning, vacuum drying. The yield is about 55%.

ΔIR (cm ^-1 ) measurement 3200 to 2900 (CH ₂ , CH ₃ ), 1720 (C = O) 1100 to 1200 (COC), 1250 (P = O)

(1) Measurement of Molecular Weight The THF solution of the copolymer was analyzed and measured by 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 2
It was 8.0%.

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 can be adjusted 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. Moreover, about the composition ratio of MPC, a hydrophobic monomer, and a hydrophilic monomer in a copolymer, 15-40: 20-50: 20-
A range of 50 is preferred. That is, when the composition ratio of MPC is smaller than 15, the water retention function and the lamellar formation promoting / stabilizing effect 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, and a fragrance may be used, 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 / PEM350 / BMA [Sample] (A) MPC / PEM350 / BMA copolymer (constituent ratio: 30/25/45, molecular weight: 12,000) (B) Chitosan (comparative product)

[Measurement method] MPC / PEM350 / BM
An ethanol solution of the A copolymer (3% by weight) and an aqueous solution of chitosan in acetic acid (3% by weight) were prepared.
After casting on a Teflon plate of cm ^2, the solvent was volatilized at room temperature to form 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 evident from the results shown in FIG. 1, the MPC / PEM350 / BMA copolymer according to the present invention comprises:
It was shown to have higher hygroscopicity than chitosan which is a comparative product.

Experiment 2. Stability of MPC / PEM350 / BMA copolymer [Sample] MPC / PEM350 / BMA (constituent ratio: 20/40/4)
0, molecular weight 15,000)

[Measurement method] pH 4.
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.

[0029]

[Table 1]

As shown in the results in Table 1, it was revealed that the MPC / PEM350 / BMA copolymer according to the present invention had excellent stability over time in a wide pH range.

[0031]

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 / PEM350 / BMA copolymer 3% by weight aqueous solution (constituent ratio 15/50/35, molecular weight 35,000) 30 Propylene glycol 5 Glycerin 2 Ethyl alcohol 5 Preservative Agent 0.3 Fragrance 0.3 Purified water 53.4

Embodiment 2 FIG. Lotion MPC / PEM350 / 2% by weight aqueous solution of styrene copolymer (constituent ratio: 30/30/40, molecular weight: 20,000) 25 Glycerin 1.5 Ethanol 6 Propylene glycol 1.5 Citric acid 0.01 0.01 Sodium citrate 0.1% 1 Fragrance 0.05 Purified water 65.84

Embodiment 3 FIG. Cream Squalane 5 2-Ethylhexanoic acid triglyceride 1 Vaseline 0.5 MPC / 2-hydroxyethyl methacrylate / acrylamide copolymer 3% by weight aqueous solution (constituent ratio: 18/50/32, molecular weight: 20,000) 50 Glycerin 31 3-butanediol 4 polyglycerin polyoxybutylene stearyl ether 2.5 perfume 0.2 purified water 33.8

Embodiment 4 FIG. Hair lotion MPC / PEM350 / methyl methacrylate copolymer 2% by weight aqueous solution (constituent ratio 35/20/45, molecular weight 45,000) 5 ethanol 10 glycerin 3 carboxymethyl chitin 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 / Acrylic acid copolymer 10% by weight aqueous solution (constituent ratio 35/30/35, molecular weight 40,000) 30 1,3-butanediol 2.5 Polyethylene glycol 200 1.5 Triethanolamine 1.0 Methylparaben 0.1 incense Charge 0.2 Purified water 16.6

(Comparative Experiment) The cosmetics obtained according to the present invention were compared with conventional cosmetics 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 / PEM35 from Emulsion of Example 1 of the Present Invention
Conventional emulsion with 0 / BMA copolymer removed (increased water)

[Experimental Method] Ten 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) Evaluation 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 (A) as compared with 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.

[0045]

[Table 2]

As is evident from the results 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 having a water retention effect. It has been proved that the skin beautiful effect such as skin activating effect and the like is remarkably excellent.

Experiment 5 (Sample) (c) Hair lotion of Example 4 of the present invention (d) MPC from hair lotion of Example 4 of the present invention
/ PEM350 / Conventional hair lotion with removal of methyl methacrylate copolymer (increased water)

[Experimental method] A bundle of 10 g (length 10 cm) of Japanese women's hair, which had not been subjected to a treatment such as perm or bleach, was bundled with a sample (c) or (d).
After applying a predetermined amount of the hair lotion, it was 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).

[0049]

[Table 3]

[0050]

[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, a gloss and a moistness of the hair which are higher than the sample (d) which is a hair lotion of the conventional product. It was clarified that all of the feelings were excellent.

Experiment 6 Stabilization of lamella layer A lamella is made from lecithin (EPC) which is an intercellular lipid analog, and MPC / PEM350 / BMA copolymer is
The arrangement of the lamellar structure composed of lecithin was made regular, and it was examined by small-angle X-ray scattering whether or not there was an effect due to tightness between molecules (stabilization and promotion of formation of the lamellar layer).

[Experimental method] Lecithin and water were mixed for 90 to 6 days.
The mixture was mixed at a weight ratio of 5:10 to 35 to prepare a lamella phase as a control product. On the other hand, a part of the water of the control was replaced with MPC / PEM3.
A lamellar phase was prepared by substituting and mixing with a 50 / BMA copolymer. Using the X-ray diffraction apparatus (JDX-3500 manufactured by JEOL), the interplanar spacing of the lamella phase was measured for the obtained lamella phase. The result is shown in FIG.

[Measurement conditions]-Small angle scattering device: DX-LSV3 manufactured by JEOL-Detector: Scintillation counter-Source: Cu wire-Voltage: 45KV-Current: 200mA-Measurement temperature: 22 to 24 ° C-Sample is a cell holder Measured between 4μm mylars

[Results] As shown in FIG.
Water = 90-65 / 10-35 wt.
A lamellar phase having a layer structure of 9 to 58 ° is formed. As water was replaced with the MPC / PEM350 / BMA copolymer solution, the d value decreased. The small-angle scattering peaks (not shown) qualitatively show that the addition of the MPC / PEM350 / BMA copolymer makes the lecithin molecules more directional and aligned than the water-added system. This is considered to reflect the following. Lamellar liquid crystal phase spacing d
Is composed of a hydrophobic portion (lecithin layer) da and an aqueous layer portion dw, and when water is replaced with the MPC / PEM350 / BMA copolymer, the d value decreases because MPC / P
This is considered to be the result of the EM350 / BMA copolymer entering the lecithin layer. Also, MPC / PEM35 is added to the lecithin layer.
It is considered that the arrangement and regularity of the molecules in the lecithin layer increased due to the penetration of the 0 / BMA copolymer. From the above, it was found that the MPC copolymer was effective in stabilizing the lamella layer by the human stratum corneum lipid and suppressing skin roughness.

[0056]

According to the present invention, of course, the skin-beautifying effect on the skin and the hair-beautifying effect on the hair based on the water retention function, the lamellar formation promoting / stabilizing action, the film forming ability and the like are remarkably excellent. It can be used without any stability 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.

FIG. 4 is a diagram showing a relationship between a water phase / oil phase ratio and a surface interval.

Continuing on the front page (72) Inventor Hideo Kuroda 560 Paula-cho, Kashio-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside the Totsuka Laboratory Co., Ltd. (72) Inventor Norio Nakabayashi 5-6-20 Koganehara, Matsudo-shi, Chiba (56) References JP-A-5-310552 (JP, A) JP-A-5-70321 (JP, A) JP-A-3-106891 (JP, A) JP-A-62-126108 (JP, A) JP-A-61-171407 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) A61K 7/00-7/50 CA (STN) REGISTRY (STN)

Claims (5)

(57) [Claims] 1. A cosmetic comprising a copolymer of 2-methacryloyloxyethyl phosphorylcholine, a hydrophobic monomer and a hydrophilic monomer. 2. The method according to claim 1, comprising one or more hydrophobic monomers selected from styrene, acrylate and methacrylate, and one or more hydrophilic monomers selected from acrylamide and polyethylene glycol monomethacrylate. Cosmetics. 3. The cosmetic according to claim 1, wherein the molecular weight of the copolymer is 5,000 or more. 4. The composition ratio of 2-methacryloyloxyethyl phosphorylcholine, hydrophobic monomer and hydrophilic monomer in the copolymer is from 15 to 40:20 to 50:20 to 5
The cosmetic according to any one of claims 1 to 3, which is 0. 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.