CN114040745A

CN114040745A - Cosmetic method

Info

Publication number: CN114040745A
Application number: CN202080048212.0A
Authority: CN
Inventors: 曾我部敦
Original assignee: Shiseido Co Ltd
Current assignee: Shiseido Co Ltd
Priority date: 2019-07-03
Filing date: 2020-06-29
Publication date: 2022-02-11
Also published as: JPWO2021002337A1; JP7595008B2; WO2021002337A1

Abstract

Provided in a high humidity environment or in a state of sweating, it can reduce sticky discomfort, etc. while ensuring the moisturizing property to the skin, and also in a low humidity environment, it can ensure the moisturizing property to the skin and improve beauty The effect of beauty methods. The cosmetic method of the present disclosure includes applying a polyvinyl alcohol film for moisturizing to a body surface.

Description

Cosmetic method

Technical Field

The present disclosure relates to cosmetic methods utilizing moisturizing effects.

Background

In recent years, various cosmetic methods have been proposed to improve the problem of skin.

Patent document 1 discloses a cosmetic method for simultaneously preventing acne and cleansing, which includes the following steps: comprises the following components (A): anti-inflammatory agent, ingredient (B): a bactericide, component (C): fatty acid ester nonionic surfactant, component (D): a humectant, and component (E): a step of impregnating the tablet with a water lotion; and a step of wiping off the dirt on the skin with a sheet impregnated with the cosmetic water.

Patent document 2 discloses a cosmetic method in which an emulsion cosmetic containing 5 to 50 mass% of an oil component is applied to the skin, and then a sheet comprising a sheet base layer and an adhesive layer capable of adhering to the skin surface and comprising the sheet base layer and the adhesive layer is stuck thereon, and the sheet as a whole has a water vapor transmission rate of 200 to 2,000g/m²24hrs of skin patch.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2016-132625

Patent document 2: japanese patent laid-open publication No. 2011-178693

Disclosure of Invention

Problems to be solved by the invention

For example, in japan, the humidity of the outdoor environment tends to be high during heavy rainy season, while the humidity tends to be low during light rainy winter season. In addition, in recent years, with the use of air conditioners and the like, a state of a considerably low humidity is sometimes formed in an indoor workplace environment, a shopping mall, and the like. In such a low humidity environment, moisture evaporates from the skin, and skin problems such as skin roughness and wrinkles tend to occur easily because moisture disappears from the skin.

In order to improve such skin problems, a procedure of applying a moisturizing agent such as glycerin to the skin is generally performed. However, even if the moisturizing agent component applied to the skin temporarily retains moisture generated from the skin to exhibit moisturizing performance, if the humidity of the outside air is low, the retained moisture evaporates into the outside air with the passage of time, and thus a sufficient moisturizing effect cannot be obtained. In addition, when the skin is sweated with such a moisturizer applied to the skin, the sweat is less likely to evaporate into the outside air due to the blocking effect of the applied moisturizer, and the feeling of discomfort of stickiness is likely to be caused.

Further, for example, since the sheet described in patent document 2 often has a certain low moisture permeability, it is considered that when a large amount of sweat is produced, the sweat cannot be efficiently evaporated into the outside air, and a sticky and sticky feeling is likely to be caused. In addition, since such a sheet is in a state in which moisture is often evaporated from the skin by the sheet, it is considered that such a sheet cannot obtain a sufficient moisturizing effect in a low humidity environment in which moisture is easily evaporated from the skin, and cannot sufficiently improve skin problems such as rough skin.

Accordingly, the subject of the present disclosure is to provide a cosmetic method that can secure moisture retention to the skin while reducing unpleasant feelings such as slimy under a high humidity environment or a state where sweat is produced, and can secure moisture retention to the skin even under a low humidity environment to improve a cosmetic effect.

Means for solving the problems

Scheme 1

A skin caring method comprises applying moisturizing polyvinyl alcohol film on body surface.

Scheme 2

The cosmetic method according to claim 1, wherein the application of the moisturizing polyvinyl alcohol film to the body surface is performed by sticking the film in the form of a separate film.

Scheme 3

The cosmetic method according to claim 1, wherein the application of the moisturizing polyvinyl alcohol film to the body surface is carried out by applying a composition containing polyvinyl alcohol and water to the body surface.

Scheme 4

The cosmetic method according to any one of claims 1 to 3, wherein the polyvinyl alcohol film for moisture retention is applied to the body surface after the waterproof moisture-permeable layer is applied to the body surface.

Scheme 5

The cosmetic method according to claim 4, wherein the application of the waterproof moisture-permeable layer to the body surface is carried out by sticking the layer in the form of a separate film.

Scheme 6

The cosmetic method according to claim 4, wherein the application of the waterproof moisture-permeable layer to the body surface is carried out by applying the constituent components of the waterproof moisture-permeable layer to the body surface.

Scheme 7

The cosmetic method according to claim 1 or 2, wherein a water-repellent moisture-permeable layer is applied to one surface of the polyvinyl alcohol film for moisture retention, and then the polyvinyl alcohol film for moisture retention is applied to the body surface through the water-repellent moisture-permeable layer.

Scheme 8

The cosmetic method according to any one of aspects 1 to 7, wherein the thickness of the moisturizing polyvinyl alcohol film is 100 μm or less.

Scheme 9

The cosmetic method according to any one of aspects 1 to 8, wherein the moisturizing polyvinyl alcohol film contains unmodified polyvinyl alcohol.

Scheme 10

The cosmetic method according to any one of aspects 4 to 9, wherein the waterproof moisture-permeable layer is at least one selected from the group consisting of an oil layer containing at least one of vaseline and liquid paraffin, a polylactic acid layer, and artificial skin.

Scheme 11

The cosmetic method according to any one of claims 1 to 10, wherein when the moisturizing polyvinyl alcohol film or the laminate comprising the moisturizing polyvinyl alcohol film and the waterproof moisture-permeable layer is evaluated by a moisture evaporation test, an amount of water evaporation measured in an environment of 23 ℃ and 40% RH is smaller than an amount of water evaporation measured in an environment of 28 ℃ and 70% RH.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present disclosure, a cosmetic method can be provided that can ensure moisture retention on the skin while reducing unpleasant feelings such as sliminess in a high-humidity environment or a state where sweat is produced, and can improve the cosmetic effect by ensuring moisture retention on the skin even in a low-humidity environment.

Drawings

Fig. 1 is a schematic view showing a moisture-shielding state in a case where the moisturizing polyvinyl alcohol film of the present disclosure is applied to the skin under a low humidity environment.

Fig. 2 is a schematic view showing the moisture permeation state in the case where the moisturizing polyvinyl alcohol film of the present disclosure is applied to the skin under a high humidity environment.

Fig. 3 is a schematic view showing the moisture permeation state in the case where the thin moisturizing polyvinyl alcohol film of the present disclosure is applied to skin having a large moisture content in a low-humidity environment.

Fig. 4 is a schematic view showing a moisture-shielded state in a case where the waterproof moisture-permeable layer and the thin moisturizing polyvinyl alcohol film of the present disclosure are applied to a skin having a large moisture content in a low-humidity environment.

Fig. 5 is a schematic view of a measurement sample sealed with a polyvinyl alcohol film used in a moisture evaporation test.

Fig. 6 is a graph showing the amount of moisture evaporated in each sample in a moisture evaporation test in an environment of 28 ℃ 70% RH (high humidity environment) and 23 ℃ 40% RH (low humidity environment).

Detailed Description

Hereinafter, embodiments of the present disclosure will be described in detail. The present disclosure is not limited to the following embodiments, and various modifications can be made within the scope of the present invention.

The cosmetic method of the present disclosure comprises applying a moisturizing polyvinyl alcohol film to a body surface.

Although not limited by the principle, the cosmetic method of the present disclosure is considered to have the following action principle that can secure moisture retention to the skin while reducing unpleasant feelings such as sliminess in a high humidity environment or a state where sweat is produced, and can secure moisture retention to the skin to improve the cosmetic effect even in a low humidity environment. In addition, in the present disclosure, polyvinyl alcohol is sometimes abbreviated as "PVA".

Skin exposed to dryness is sometimes unconsciously deprived of water and is in a state of not retaining the water content of the stratum corneum on the skin surface. If the moisture content of the skin becomes insufficient, a Moisturizing component (natural Moisturizing Factor (NMF)) produced by the skin itself cannot be produced smoothly. As a result, the barrier function and the moisturizing function on the skin surface are reduced, and the skin is likely to be damaged, so that the skin is likely to lose moisture and become rough.

Further, if the state of insufficient water content of the stratum corneum on the skin surface continues, the damaged stratum corneum is repaired in order to rapidly produce new cells, so that the rate of regeneration (renewal) of the skin becomes high, and simultaneously, immature and incomplete cells are successively produced. As a result, preparation for making a normal stratum corneum is insufficient, and it is considered that the skin surface does not retain sufficient moisture, and the skin roughness continues in such a vicious cycle.

PVA is generally known to have excellent affinity for moisture. For example, as shown in fig. 1, when the PVA film 101 is applied to the skin, it is considered that the moisture 105 evaporated from the skin is linked to the PVA molecules 103 in the film, and the PVA molecules 103 move so as to be drawn closer to each other with the moisture 105 as the center, thereby generating the gap 107 through which the moisture passes. However, if the humidity of the external environment is low, it is considered that the movement of the PVA molecules 103 does not occur in the vicinity of the outermost surface of the PVA film 101, and therefore the gap 107 through which moisture passes is not formed. As a result, it is considered that the moisture evaporated from the skin stays at the lower position of the outermost surface of the PVA film in the low humidity environment and is not evaporated into the atmosphere, and therefore the skin can be sufficiently moisturized even in the low humidity environment. This improves the production function of the moisturizing component produced by the skin itself, and also improves the failure of the renewal in the stratum corneum, and thus it is considered that the skin problems such as skin roughness are unlikely to occur, and the cosmetic effect is improved.

On the other hand, in a high humidity environment or a state where a large amount of sweat is produced, for example, as shown in fig. 2, it is considered that the PVA molecules 203 in the vicinity of the outermost surface of the PVA film 201 also move so as to be drawn closer to each other with the moisture 205 as the center, and a gap 207 through which the moisture passes is generated in the entire region in the thickness direction of the film. As a result, it is considered that in such a situation, excessive moisture such as sweat can be evaporated from the skin, and therefore, the unpleasant feeling of slimy paste can be reduced. Further, it is considered that, in the case where the skin is dry and under a high humidity environment, moisture in the environment can be supplied to the skin through the PVA film 201.

As shown in fig. 3, for example, when the PVA film 301 is thin and the moisture content of the skin is large, a gap 307 through which moisture passes is formed even in a low humidity environment, and moisture may evaporate from the skin. In such a case, as shown in fig. 4, by applying the waterproof moisture-permeable layer 409 between the PVA film 401 and the skin, the formation of the gap 407 through which moisture passes can be suppressed. The waterproof moisture-permeable layer 409 suppresses the movement of moisture from the exposed skin, although it has moisture permeability. Therefore, since the moisture 408 passing through the waterproof moisture-permeable layer 409 penetrates into the PVA film 401 at a smaller rate than in the case where such a waterproof moisture-permeable layer 409 is not present, it is considered that even in the above case, the gap 407 through which the moisture passes with the movement of the PVA molecules 403 is not formed in the vicinity of the outermost surface of the PVA film 401, and the skin can be moisturized and the cosmetic effect can be improved.

The terms in this disclosure are defined as follows.

The term "humidity responsiveness" as used herein refers to a performance in which the amount of water evaporated varies according to a change in the humidity environment, and specifically, a performance in which the amount of water evaporated in a low humidity environment is smaller than the amount of water evaporated in a high humidity environment.

The "low humidity environment" in the present disclosure means an environment in which the relative humidity at 23 ℃ under atmospheric pressure is 50% RH or less, 45% RH or less, 40% RH or less, 35% RH or less, or 30% RH or less. The lower limit of the relative humidity is not particularly limited, and may be, for example, 3% RH or more, 5% RH or more, 7% RH or more, or 10% RH or more. The relative humidity may be converted to absolute humidity by weight which is not affected by temperature, for example, and may be 8.7g/kg or less, 7.9g/kg or less, 7.0g/kg or less, 6.1g/kg or less, or 5.2g/kg or less, or 0.52g/kg or more, 0.86g/kg or more, 1.2g/kg or more, or 1.7g/kg or more as absolute humidity by weight.

The "high humidity environment" in the present disclosure means an environment in which the relative humidity at 28 ℃ under atmospheric pressure is 50% RH or more, 55% RH or more, 60% RH or more, 65% RH or more, 70% RH or more, or 75% RH or more. The upper limit of the relative humidity is not particularly limited, and may be, for example, 100% RH or less than 100% RH. The relative humidity may be converted to absolute humidity by weight which is not affected by temperature, and may be 12g/kg or more, 13g/kg or more, 14g/kg or more, 15g/kg or more, 17g/kg or more, or 18g/kg or more, or 24g/kg or less than 24g/kg as absolute humidity by weight.

In the present disclosure, the term "film" includes not only a film that can be moved independently, such as a packaging film, but also a film-like film that cannot be moved independently, such as a coating film. In the present disclosure, a film that can be moved independently, such as a packaging film, may be referred to as an "independent film", and a film-like film that cannot be moved independently may be referred to as an "dependent film".

The term "beauty" or "beauty method" in the present disclosure means a method of applying the cosmetic material of the present disclosure to a body surface to beautify the state of the body surface, or a method of beautifying the state of the body surface, and is different from a method of performing surgery, treatment, or diagnosis on a human.

By "body surface" in this disclosure is meant the skin surface of the body.

Polyvinyl alcohol film for moisture retention

The moisturizing polyvinyl alcohol film (sometimes simply referred to as "polyvinyl alcohol film" or "PVA film") used in the cosmetic method of the present disclosure is a film having humidity responsiveness. Such humidity responsiveness can be evaluated by the amount of water evaporated calculated by the water evaporation test. The amount of water evaporation is also sometimes referred to herein as the water evaporation rate. Further, since the moisturizing polyvinyl alcohol film can exhibit a cosmetic effect, a structure including such a moisturizing polyvinyl alcohol film is sometimes referred to as a "moisturizing film cosmetic material" or simply a "cosmetic material".

Evaluation method 1

As shown in fig. 5, the amount of water evaporated can be calculated as the amount of water decreased per unit area and unit time by covering the open part of a vial charged with 20mL of water with a sample for measurement such as a PVA film, and allowing the vial to stand in a low humidity environment at 23 ℃ and 40% RH until the amount of evaporation becomes a substantially constant equilibrium state with respect to time, and then measuring the amount of water decreased.

The polyvinyl alcohol film of the present disclosure can exhibit humidity responsiveness such that, when evaluated by a moisture evaporation test using a moisture evaporation amount, for example, a moisture evaporation amount measured under a low humidity environment of 23 ℃ 40% RH is smaller than a moisture evaporation amount measured under a high humidity environment of 28 ℃ 70% RH. On the other hand, in the case of an open system or a vial covered with filter paper, the amount of water evaporated when measured in a low humidity environment of 40% RH at 23 ℃ is larger than that when measured in a high humidity environment of 70% RH at 28 ℃.

Specifically, the polyvinyl alcohol film of the present disclosure can be reduced in the amount of water evaporated by 0.20mg/cm when measured in a low humidity environment at 23 ℃ and 40% RH compared with the amount of water evaporated when measured in a high humidity environment at 28 ℃ and 70% RH²More than h, 0.25mg/cm²More than h, 0.30mg/cm²More than h, 0.40mg/cm²More than h, 0.45mg/cm²More than h, or 0.50mg/cm²More than h, and further, the upper limit thereof may be 1.3mg/cm²Less than h, 1.2mg/cm²Less than h, 1.0mg/cm²Less than h, or 0.95mg/cm²The ratio of the reaction time to the reaction time is less than h.

In addition, if the atmosphere of the measurement environment is, for example, an environment having a lower humidity than the environment of 23 ℃ 40% RH, the polyvinyl alcohol film of the present disclosure can further suppress evaporation of moisture. Therefore, if the difference between the humidity environments of the measured atmosphere is large, the difference between the water evaporation amount and the water evaporation ratio described later tends to be large.

Evaluation method 2

The humidity responsiveness can also be evaluated using the water evaporation ratio (%) obtained by the following procedure. First, a vial having an open system into which 20mL of water is charged is left standing in a low humidity environment of, for example, 23 ℃ 40% RH until the evaporation amount becomes an equilibrium state almost constant with respect to time, and then the amount of water decrease is measured, and the water evaporation amount 1, which is the amount of water decrease per unit area and unit time, is calculated. Next, as shown in fig. 5, the open part of another vial into which 20mL of water was introduced was covered with a measurement sample such as a PVA film, and left to stand in the same environment until the vial became an equilibrium state, and then the amount of water decreased was measured, and the amount of water evaporated 2, which is the amount of water decreased per unit area and unit time, was calculated. Then, the ratio of the water evaporation amount 2 to the water evaporation amount 1 can be obtained as a percentage to calculate the water evaporation ratio.

The polyvinyl alcohol film of the present disclosure can exhibit humidity responsiveness such that, when evaluated by a moisture evaporation test using a moisture evaporation ratio, for example, a moisture evaporation ratio measured in a low humidity environment of 23 ℃ 40% RH is less than a moisture evaporation ratio measured in a high humidity environment of 28 ℃ 70% RH. On the other hand, in the case of an open system or a vial covered with filter paper, the amount of water evaporated when measured in a low humidity environment of 40% RH at 23 ℃ is larger than that when measured in a high humidity environment of 70% RH at 28 ℃.

Specifically, the polyvinyl alcohol film of the present disclosure may have a water evaporation rate measured in a low humidity environment at 23 ℃ and 40% RH that is less than the water evaporation rate measured in a high humidity environment at 28 ℃ and 70% RH by 2.0% or more, 2.5% or more, 3.0% or more, 3.5% or more, or 4.0% or more, and the upper limit thereof may be 10% or less, 9.5% or less, 9.0% or less, or 8.5% or less.

In the polyvinyl alcohol film, from the viewpoint of reducing or suppressing evaporation of moisture in a low-humidity environment, it is preferable that the film not be a film in which holes are not formed on the entire surface in order to impart moisture permeability, such as a nonwoven fabric or a film in which through holes are physically provided. However, as long as the polyvinyl alcohol film of the present disclosure can exhibit the above humidity responsiveness, for example, in order to improve air retention at the time of application of the film, the through-holes may be partially formed in the film.

Material(s)

The material constituting the polyvinyl alcohol film of the present disclosure is not particularly limited as long as the resulting film exhibits humidity responsiveness, and polyvinyl alcohol or a derivative thereof may be used alone or in combination of two or more. Examples of the polyvinyl alcohol derivative include modified polyvinyl alcohol, polyvinyl acetate, and polyvinyl butyral. In addition, from the viewpoint of humidity responsiveness, such a film is preferably composed of unmodified polyvinyl alcohol and/or polyvinyl alcohol subjected to modification treatment.

Examples of the polyvinyl alcohol include completely saponified polyvinyl alcohol having a saponification degree of 99% or more, partially saponified polyvinyl alcohol having a saponification degree of 90% or more and less than 99%, and partially saponified polyvinyl alcohol having a saponification degree of 70% or more and less than 90%. These polyvinyl alcohols may be used alone or in combination of two or more. Among these, from the viewpoint of humidity responsiveness, particularly, an effect of suppressing water evaporation in a low humidity environment, fully saponified polyvinyl alcohol and partially saponified polyvinyl alcohol are preferable, and fully saponified polyvinyl alcohol is more preferable. Examples of the modification treatment of polyvinyl alcohol include glycol modification, anion modification, and cation modification.

From the viewpoint of humidity responsiveness, particularly the effect of suppressing water evaporation in a low humidity environment, unmodified polyvinyl alcohol or polyvinyl alcohol subjected to glycol modification treatment is preferable, and unmodified polyvinyl alcohol is more preferable.

Commercially available polyvinyl alcohols can be used. Examples of the unmodified fully saponified polyvinyl alcohol include ゴーセノール (trade mark) NL-05 (manufactured by Mitsubishi ケミカル Co., Ltd.), KURARAY POVAL (trade mark) PVA-117H (manufactured by Kokai クラレ Co., Ltd.), KURARAY POVAL (trade mark) PVA-124 (manufactured by Kokai クラレ Co., Ltd.), examples of the anion modified fully saponified polyvinyl alcohol include ゴーセネックス (trade mark) T-330H (manufactured by Mitsubishi ケミカル Co., Ltd.), and examples of the diol modified fully saponified polyvinyl alcohol include ニチゴー G ポリマー (trade mark) OKS-1089 and ニチゴー G ポリマー (trade mark) OKS-1109 (both manufactured by Mitsubishi ケミカル Co., Ltd.).

Examples of the unmodified partially saponified polyvinyl alcohol include KURARAAY POVAL (trademark) PVA-617 (manufactured by KOKAI クラレ), and examples of the diol-modified partially saponified polyvinyl alcohol include ニチゴー G ポリマー (trademark) OKS-8096 (manufactured by Mitsubishi ケミカル).

Examples of the unmodified partially saponified polyvinyl alcohol include ゴーセノール (trade mark) GM-14, ゴーセノール (trade mark) PVA EG-05, ゴーセノール (trade mark) PVA EG-40 (both manufactured by Mitsubishi ケミカル Co., Ltd.), KURARARAY POVAL (trade mark) PVA-235 (manufactured by クラレ Co., Ltd.), and examples of the cationically modified partially saponified polyvinyl alcohol include ゴーセノール (trade mark) PVA K-434 (manufactured by Mitsubishi ケミカル Co., Ltd.).

Thickness

The thickness of the polyvinyl alcohol film is not particularly limited, and can be appropriately adjusted depending on the site to which the polyvinyl alcohol film is applied, the purpose of use, the amount of sweat glands of a user, the amount of moisture evaporated from the skin, the balance of humidity responsiveness when combined with a waterproof moisture-permeable layer described later, and the like. For example, the thickness of the polyvinyl alcohol film may be 100 μm or less, 70 μm or less, 50 μm or less, 20 μm or less, 15 μm or less, 13 μm or less, 10 μm or less, 7 μm or less, 5 μm or less, 3 μm or less, 1 μm or less, or 0.5 μm or less, or may be 0.01 μm or more, 0.05 μm or more, 0.1 μm or more, 0.2 μm or more, or 0.3 μm or more. In particular, when used in combination with a waterproof moisture-permeable layer described later, the thickness of the polyvinyl alcohol film may be as thin as 15 μm or less, 13 μm or less, 10 μm or less, 7 μm or less, 5 μm or less, 3 μm or less, 1 μm or less, 0.7 μm or less, or 0.5 μm or less, and may be 0.01 μm or more, 0.05 μm or more, 0.1 μm or more, 0.2 μm or more, or 0.3 μm or more.

When the polyvinyl alcohol film is a stand-alone film, the thickness of the polyvinyl alcohol film can be defined as an average value calculated by measuring the thickness of an arbitrary portion of the film at least 5 times using a high-precision digital micrometer (MDH-25MB, manufactured by ミツトヨ). When the thickness of the polyvinyl alcohol film is too thin to be measured by a high-precision digital micrometer, the thickness of the polyvinyl alcohol film can be determined by the same method using a scanning electron microscope as described below.

When the polyvinyl alcohol film is combined with a waterproof moisture-permeable layer described later to form a laminate and the waterproof moisture-permeable layer cannot be separated from the laminate, a cross section of the laminate in the thickness direction is measured using a scanning electron microscope. Further, the average value of the thickness of any at least 5 places of the polyvinyl alcohol films in the laminate may be defined as the thickness of the polyvinyl alcohol film.

Weight per unit area

The polyvinyl alcohol film may be defined by a weight per unit area instead of a thickness. Here, the weight per unit area of the present disclosure may be regarded as 1cm per unit²Weight of film (mg). The weight per unit area of the polyvinyl alcohol film may be, for example, 0.0010mg/cm²Above, 0.0060mg/cm²Above, 0.010mg/cm²Above, 0.025mg/cm²Above, 0.035mg/cm²Above, 0.050mg/cm²Above, 0.070mg/cm²Above, 0.10mg/cm²Above, 0.15mg/cm²Above, 0.30mg/cm²Above, or 0.45mg/cm²The concentration of the above-mentioned metal salt may be 12.0mg/cm²Below, 8.5mg/cm²Below, 6.0mg/cm²4.5mg/cm below²2.5mg/cm below²2.0mg/cm or less²1.5mg/cm below²1.2mg/cm below²1.0mg/cm or less²Below, 0.80mg/cm²Below, 0.60mg/cm²Below, 0.35mg/cm²Below, 0.15mg/cm²Below, 0.10mg/cm²0.085mg/cm below²Below, or 0.060mg/cm²The following.

(optional ingredients)

In the polyvinyl alcohol film of the present disclosure, various components may be appropriately blended within a range not affecting the effect of the present invention. Examples of the various components include a humectant, a polymer (e.g., a carboxyvinyl polymer, (N, N-dimethylacrylamide-2-acrylamidodimethylpropane sulfonic acid) crosslinked copolymer, a copolymer of 2-Methacryloxyphosphocholine (MPC) and N-Butyl Methacrylate (BMA), a rubber, an elastomer, an adhesive, an adhesion modifier, an ultraviolet absorber, an antioxidant, a preservative, an antioxidant aid, a crosslinking agent, a light diffusing agent, a filler, a skin nutrient, a vitamin, various drugs applicable to medicines, quasi-medicines, cosmetics, etc., an organic powder, a pigment, a dye, a pigment, a perfume, and any of these components may be used alone or in combination of two or more, therefore, as the humectant, humectants other than glycerin, such as dipropylene glycol, POE (14) POP (7) dimethyl ether, and the like are preferable. Here, POE means polyoxyethylene, and POP means polyoxypropylene.

Water-proof moisture-permeable layer

The waterproof moisture-permeable layer used in the cosmetic method of the present disclosure is a layer having both water resistance and moisture permeability, and such a layer alone is a layer that does not exhibit humidity responsiveness.

As shown in fig. 3, for example, when the polyvinyl alcohol film 301 is thin and the moisture content of the skin is large, a gap 307 through which moisture passes is formed even in a low humidity environment, and moisture may evaporate from the skin. In such a case, as shown in fig. 4, by applying the waterproof moisture-permeable layer 409 between the polyvinyl alcohol film 401 and the skin, the formation of the gap 407 through moisture can be suppressed, and moisture retention can be ensured.

Further, if the polyvinyl alcohol film is thickened, rigidity or the like increases, and the polyvinyl alcohol film may be difficult to apply to the skin or may be poor in aesthetic appearance. Even if the waterproof moisture-permeable layer is thin, if combined with a polyvinyl alcohol film, a laminate including these layers can provide sufficient humidity responsiveness, similarly to the humidity responsiveness of the polyvinyl alcohol film, and therefore the overall thickness can be reduced. As a result, the laminate having such a structure can be improved in the applicability to the skin and the appearance as compared with the case of using a thick polyvinyl alcohol film.

The surface of the polyvinyl alcohol film opposite to the surface on the body surface side is used for adjusting the moisture permeability to the external environment, and therefore it is preferable that no waterproof moisture-permeable layer or any additional layer is formed on such a surface. Therefore, when the waterproof moisture-permeable layer is applied to the polyvinyl alcohol film in advance, it is preferable that such a waterproof moisture-permeable layer is disposed on the body surface side of the polyvinyl alcohol film.

The waterproof moisture-permeable layer may be constituted by a single layer, or may be constituted by a laminate. The waterproof moisture-permeable layer may be in the form of a stand-alone film or a non-stand-alone film. Further, the waterproof moisture-permeable layer may be constituted in such a manner as to be applied to the whole surface or a part of the polyvinyl alcohol film.

Material(s)

The waterproof moisture-permeable layer is not particularly limited as long as it can exhibit the humidity responsiveness when combined with a polyvinyl alcohol film. Examples of the waterproof moisture-permeable layer include at least one selected from an oil layer, a polylactic acid layer, and artificial skin.

Examples of the material of the oil layer include polar oils such as ester oils, and nonpolar oils such as hydrocarbon oils. Among them, nonpolar oils are preferable from the viewpoint of humidity responsiveness.

Examples of the nonpolar oil include vaseline, liquid paraffin, tetraisobutane, hydrogenated polydecene, olefin oligomer, isododecane, isohexadecane, squalane, polybutene, hydrogenated polybutene, polyisobutylene, and hydrogenated polyisobutylene. These may be used alone or in combination of two or more. Among them, vaseline and liquid paraffin are preferable from the viewpoint of moisture responsiveness.

As a material constituting the artificial skin, for example, rubbers such as urethane rubber, olefin rubber, silicone rubber, acrylic rubber, natural rubber, etc., elastomers, or α -gels, etc. can be used. These may be used alone or in combination of two or more. Among them, silicone rubber is preferable from the viewpoint of flexibility, humidity responsiveness, and the like.

Thickness

The thickness of the waterproof moisture-permeable layer is not particularly limited, and can be appropriately adjusted depending on the site to which the waterproof moisture-permeable layer is applied, the purpose of use, the amount of sweat glands or the amount of moisture evaporated from the skin of the user, the balance of humidity responsiveness when combined with the polyvinyl alcohol film, and the like.

Weight per unit area

The waterproof moisture-permeable layer may be defined by a weight per unit area, for example. The weight per unit area of the waterproof moisture-permeable layer may be, for example, 1.0mg/cm²Above, 1.2mg/cm²Above, or 1.4mg/cm²The concentration of the above-mentioned metal salt may be 2.0mg/cm²1.8mg/cm below²Below, or 1.6mg/cm²The following.

(optional ingredients)

In the waterproof moisture-permeable layer of the present disclosure, various components may be appropriately blended within a range not affecting the effect of the present invention. Examples of the various components include a moisturizer, a polymer, rubber, an elastomer, an adhesive modifier, an adhesion modifier, an ultraviolet absorber, an antioxidant, a preservative, an antioxidant aid, a light diffusing agent, a filler, a skin nutrient, vitamins, various medicines applicable to medicines, quasi-medicines, cosmetics, etc., an organic powder, a pigment, a dye, a pigment, and a perfume. These arbitrary components may be used alone or in combination of two or more.

(optional constituent layers)

The polyvinyl alcohol film for moisture retention of the present disclosure may be used in combination with any constituent layer within a range not affecting the effect of the present invention. Examples of such constituent layers include an adhesive layer having moisture permeability (for example, an adhesive layer having through holes), a protective film having peeling performance, a release sheet, and the like, and these may be used alone or in combination of two or more. For example, a protective film may be applied to one side of the polyvinyl alcohol film and/or a release sheet may be applied to the opposite side. Here, the surface of the protective film or the release sheet may be subjected to a release treatment of silicone or the like. The protective film and the release sheet may have the same or different release properties from the polyvinyl alcohol film. From the viewpoint of easiness of peeling of the polyvinyl alcohol film, it is preferable that they have different peeling properties.

The material of any of the layers is not particularly limited, but from the viewpoint of handling properties, polyolefin such as polyethylene and polypropylene, polyester such as polyethylene terephthalate, cotton, paper, and the like can be given. Any of the constituent layers may be in the form of a film, or may be in the form of a nonwoven fabric, a knitted fabric, or a woven fabric.

Method for beautifying skin using moisturizing polyvinyl alcohol film

The cosmetic method of the present disclosure is carried out by applying a moisturizing polyvinyl alcohol film to a body surface. The moisturizing polyvinyl alcohol film applied to the skin can reduce or inhibit the evaporation of moisture from the skin in a low-humidity environment, and can sufficiently moisturize the skin even in a low-humidity environment. As a result, the function of producing moisturizing components produced by the skin itself is improved, and the unevenness of the renewal in the stratum corneum is also improved, so that skin problems such as skin roughness are less likely to occur, and the cosmetic effect can be improved.

The means for applying the polyvinyl alcohol film to the body surface is not particularly limited, and for example, the polyvinyl alcohol film may be applied to the body surface in the form of a separate film or may be applied by applying a composition for the preparation of a polyvinyl alcohol film described later to the body surface.

As means for sticking the polyvinyl alcohol film to the body surface in the form of a separate film, for example, in the case where the polyvinyl alcohol film includes a moisture-permeable adhesive layer, it can be stuck to the body surface via such an adhesive layer. Alternatively, since the polyvinyl alcohol film exhibits adhesiveness when it comes into contact with water, the film may be applied to a body surface after applying water, lotion, or the like to a body surface part to which the film is applied, or the film may be applied to the body surface after applying water, lotion, or the like to the polyvinyl alcohol film.

The means for applying the composition for producing a polyvinyl alcohol film to the body surface may be, for example, a method in which the composition is sprayed from a spray container in which the composition is charged so as to form a film, or a method in which the composition is charged into a container having no spray function, and an appropriate amount of the composition is collected from such a container by a finger or the like and applied to the body surface.

The application of the polyvinyl alcohol film to the body surface can be carried out after the waterproof moisture-permeable layer is applied to the body surface. In this case, the application of the waterproof moisture-permeable layer to the body surface may be carried out, for example, by sticking the waterproof moisture-permeable layer in the form of a separate film or by applying the constituent components of the waterproof moisture-permeable layer to the body surface. Here, the application of the polyvinyl alcohol film to the waterproof moisture-permeable layer may be performed by the same method as the means for applying the polyvinyl alcohol film to the body surface, or, in the case where the waterproof moisture-permeable layer itself has adhesiveness, the polyvinyl alcohol film may be attached by utilizing the adhesiveness thereof.

As a means for attaching the waterproof moisture-permeable layer in the form of a separate film to the body surface, for example, in the case where the waterproof moisture-permeable layer itself has adhesiveness, the waterproof moisture-permeable layer in such a form may be directly attached to the body surface. When the waterproof moisture-permeable layer itself does not have adhesiveness, the waterproof moisture-permeable layer in such a form may be attached to a body surface via, for example, an adhesive layer having moisture permeability or another waterproof moisture-permeable layer having adhesiveness.

The coating of the components constituting the water-repellent moisture-permeable layer on the body surface can be carried out by the same method as that for the above-mentioned composition for producing a polyvinyl alcohol film, by preparing a composition containing various components constituting the water-repellent moisture-permeable layer.

The application of the polyvinyl alcohol film to the body surface may be carried out by applying the polyvinyl alcohol film to the body surface through a waterproof moisture-permeable layer after applying the waterproof moisture-permeable layer to one surface of the polyvinyl alcohol film. Here, when the application of the waterproof moisture-permeable layer to the polyvinyl alcohol film has adhesiveness in itself, the application can be applied to the polyvinyl alcohol film by utilizing the adhesiveness. In addition, in the case where the waterproof moisture-permeable layer does not have adhesiveness, the waterproof moisture-permeable layer may be applied to the polyvinyl alcohol film via a moisture-permeable adhesive layer or another waterproof moisture-permeable layer having adhesiveness. In this case, a polyvinyl alcohol film having a non-adhesive waterproof moisture-permeable layer can be applied to the body surface by applying a moisture-permeable adhesive layer or another adhesive waterproof moisture-permeable layer to the body surface side of the waterproof moisture-permeable layer, or by applying a moisture-permeable adhesive layer or another adhesive waterproof moisture-permeable layer to the body surface.

Application site of polyvinyl alcohol film for moisture retention

The polyvinyl alcohol film for moisture retention may be attached to any position as long as it is on the surface of the skin in all parts of the body, that is, on the body surface. For example, the adhesive sheet can be appropriately attached to the skin surface of the face (lips, the periphery of the eyes, nose, cheeks, forehead, etc.), neck, ears, hands, arms, legs, feet, chest, abdomen, back, etc. Here, the skin also includes nails hardened by changing the cutin of the epidermis of the skin.

Method for producing polyvinyl alcohol film for moisture retention

The polyvinyl alcohol film for moisture retention of the present disclosure can be produced, for example, by using a commercially available polyvinyl alcohol film having a predetermined thickness, or can be produced by using a composition for producing a polyvinyl alcohol film.

As a method for producing a composition for use in the production of a polyvinyl alcohol film, for example, such a composition can be applied to a release sheet by any means, for example, known application means such as offset printing, gravure coating, bar coating, knife coating, spray coating, etc., and can be continuously prepared by any means, for example, a drying step, a crosslinking step, a step of applying a waterproof moisture-permeable layer, a step of bonding constituent layers such as a protective film, a winding step, etc.

The polyvinyl alcohol film for moisture retention of the present disclosure may be prepared by using a composition for preparing a polyvinyl alcohol film, not continuously. For example, a predetermined amount of such a composition may be added to a container, a mold, or the like, and dried to prepare a polyvinyl alcohol film. In this case, for example, a waterproof moisture-permeable layer, a protective film, a release sheet, or the like may be applied to the obtained polyvinyl alcohol film as needed. Alternatively, the composition may be put into, for example, a tube container, a spray container, or the like, and the composition may be applied to the body surface from such a container, or the composition may be applied to a waterproof moisture-permeable layer previously applied to the body surface and dried to directly form a polyvinyl alcohol film on the body surface.

The polyvinyl alcohol film for moisture retention can be appropriately adjusted in size and shape depending on the site of application or the like of such a film or a laminate including the film, by using a known cutting means such as half-cutting or laser cutting.

Composition for preparing polyvinyl alcohol film

The polyvinyl alcohol film for moisture retention of the present disclosure can be prepared using a composition for preparing a polyvinyl alcohol film. Such a composition can be prepared by appropriately mixing the polyvinyl alcohol, water, and any of the following components.

(optional Components)

In the composition for producing a polyvinyl alcohol film of the present disclosure, various components may be appropriately blended in a range not affecting the effect of the present invention. Examples of the various components include lower alcohols, polyhydric alcohols, higher alcohols, oil components, various extracts, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants, moisturizers, polymers, rubbers, elastomers, adhesives, adhesion modifiers, ultraviolet absorbers, antioxidants, preservatives, antioxidant aids, crosslinking agents, light diffusing agents, fillers, gelling agents (thickeners), skin nutrients, vitamins, various drugs applicable to drugs, quasi drugs, cosmetics, and the like, organic powders, pigments, dyes, pigments, and perfumes. These arbitrary components may be used alone or in combination of two or more.

Cosmetics set

The polyvinyl alcohol film for moisture retention of the present disclosure may be provided in the form of a cosmetic kit including the polyvinyl alcohol film or a composition for producing the polyvinyl alcohol film.

Optional Member

The cosmetic product kit can furthermore have any desired components. Examples of such an arbitrary member include a member to which the waterproof moisture-permeable layer can be applied, a knife, scissors, a mirror, and the like. These arbitrary members may be provided in the cosmetic kit alone or in combination of two or more kinds.

Examples

The present invention will be described in further detail below with reference to examples, but the present invention is not limited thereto.

Examples 1 to 3 and comparative examples 1 to 2

The polyvinyl alcohol (PVA) films obtained by the production methods described in examples 1 to 3, and the filter paper (comparative example 1) and the polylactic acid film (comparative example 2) used for comparison were evaluated for humidity responsiveness by the moisture evaporation test described below. The results are shown in table 1 and fig. 6. In addition, as a reference example, the results of the open system sample are shown in table 1.

Moisture evaporation test

A round open part (radius: 0.7cm, area: 1.54 cm) of a vial into which 20mL of water was put was placed²) The vials were covered with the respective measurement samples and allowed to stand in a constant temperature bath under predetermined temperature and humidity conditions. After leaving the flask for about 2 to 3 days until the evaporation amount becomes almost constant in equilibrium with time, the amount of water in the flask is measured and the amount of water evaporated is calculated as the amount of water reduced per unit area and unit time. Here, the test was conducted under two environments, namely, a low humidity environment at 23 ℃ and 40% RH and a high humidity environment at 28 ℃ and 70% RH.

EXAMPLE 1

KURARAY POVAL (trade Mark) PVA-117H (manufactured by クラレ Co., Ltd.) as an unmodified completely saponified polyvinyl alcohol and ion-exchanged water were mixed and stirred in a 10mL vial so that the polyvinyl alcohol concentration became 5.0 mass%, to prepare a polyvinyl alcohol film-forming composition. Then, 3.0g of the obtained 5.0 mass% aqueous solution of the composition was added to an area of 19.6cm²The resulting solution was dried in a substantially circular dish to prepare a sample for measurement, which had a thickness of about 60 μm and a weight per unit area of about 7.6mg/cm²The polyvinyl alcohol film of (1).

EXAMPLE 2

A polyvinyl alcohol film as a sample for measurement was prepared in the same manner as in example 1, except that the concentration of polyvinyl alcohol was changed to 1.0 mass%. The resulting film had a thickness of about 10 μm and a weight per unit area of about 1.5mg/cm²。

< example 3>

A polyvinyl alcohol film as a sample for measurement was prepared in the same manner as in example 1, except that the concentration of polyvinyl alcohol was changed to 0.5 mass%. The resulting film had a thickness of about 6 μm and a weight per unit area of about 0.76mg/cm²。

< comparative example 1>

The thickness of the film was 250 μm, and the weight per unit area was 14mg/cm²The filter paper #133 manufactured by ADVANTEC corporation of (1) was used as a sample for measurement in comparative example 1.

< comparative example 2>

A0.1 mass% polylactic acid solution was prepared using tetrahydrofuran, and the solution was applied by a spin coating method to prepare a solution having a thickness of about 200nm and a weight per unit area of about 0.025mg/cm²The polylactic acid film of (1). The sample for measurement of comparative example 2 was prepared by stacking two sheets of the polylactic acid film.

< reference example 1>

As a reference example, a sample of an open system in which the open part of the vial was not covered was used.

TABLE 1

< results >

As is clear from table 1 and fig. 6, in the case of the filter paper of comparative example 1 and the polylactic acid film of comparative example 2, the evaporation amount of moisture is large in the low humidity environment compared to the high humidity environment, and humidity responsiveness is not exhibited. On the other hand, the polyvinyl alcohol films of examples 1 to 3 were confirmed to exhibit a significantly lower moisture evaporation amount in a low humidity environment than in a high humidity environment, and to exhibit humidity responsiveness.

EXAMPLES 4 and 5 AND COMPARATIVE EXAMPLE 3

The amount of water evaporated from human skin was evaluated, and the results are summarized in table 2. Here, the amount of water evaporated was measured using a VAPO METER manufactured by キ - ストン under two environments of a low humidity environment at 23 ℃ and 40% RH and a high humidity environment at 28 ℃ and 70% RH.

< example 4>

The polyvinyl alcohol film (thickness: about 10 μm) obtained in example 2 was attached to the skin surface of the inner side of the human left arm.

< example 5>

Vaseline (サンホワイト P-1, manufactured by Nidian リカ Co., Ltd.) was added to the skin surface of the inner side of the left arm of a human body at a concentration of about 1.5mg/cm²The above ratio was applied to form a waterproof moisture-permeable layer, and the polyvinyl alcohol film (thickness: about 10 μm) obtained in example 2 was laminated thereon.

< comparative example 3>

The amount of water evaporated was measured for the original skin.

TABLE 2

< results >

As is clear from table 2, the amount of moisture evaporated by the skin itself is originally larger in a low humidity environment than in a high humidity environment. On the other hand, in the case of examples 4 and 5 in which a polyvinyl alcohol film was applied, it was confirmed that the unpleasant feeling of slimy was not exhibited in a high humidity environment, and the moisture evaporation amount in a low humidity environment was suppressed to be lower than that in a high humidity environment, and the moisture retention performance of the skin in a low humidity environment was improved. In addition, in a high humidity environment, the amount of water evaporated in example 4 is larger than that in comparative example 3, and this is considered to be because the measurement position of the original skin in comparative example 3 is different from the position where the PVA film of example 4 is applied to the original skin, that is, the amount of water evaporated from the original skin in each measurement position is different.

Description of the symbols

100. 200, 300 and 400 moisturizing film cosmetic

101. 201, 301, 401 polyvinyl alcohol film

103. 203, 303, 403 polyvinyl alcohol molecules

105. 205, 305, 405 moisture

107. 207, 307, 407 pass through the gap of moisture

408 moisture passing through the waterproof moisture-permeable layer

409 waterproof moisture permeable layer.

Claims

1. A skin caring method comprises applying moisturizing polyvinyl alcohol film on body surface.

2. The cosmetic method according to claim 1, wherein the application of the moisturizing polyvinyl alcohol film to the body surface is performed by sticking the film in the form of a separate film.

3. The cosmetic method according to claim 1, wherein the application of the moisturizing polyvinyl alcohol film to the body surface is carried out by applying a composition comprising polyvinyl alcohol and water to the body surface.

4. The cosmetic method according to any one of claims 1 to 3, wherein the polyvinyl alcohol film for moisture retention is applied to the body surface after a waterproof moisture-permeable layer is applied to the body surface.

5. The cosmetic method according to claim 4, wherein the application of the waterproof and moisture-permeable layer to the body surface is carried out by sticking in the form of a separate film.

6. The cosmetic method according to claim 4, wherein the application of the waterproof moisture-permeable layer to the body surface is carried out by applying the constituent components of the waterproof moisture-permeable layer to the body surface.

7. The cosmetic method according to claim 1 or 2, wherein the polyvinyl alcohol film for moisture retention is applied to a body surface via a waterproof moisture-permeable layer after the waterproof moisture-permeable layer is applied to one surface of the polyvinyl alcohol film for moisture retention.

8. The cosmetic method according to any one of claims 1 to 7, wherein the thickness of the moisturizing polyvinyl alcohol film is 100 μm or less.

9. The cosmetic method according to any one of claims 1 to 8, wherein the moisturizing polyvinyl alcohol film comprises unmodified polyvinyl alcohol.

10. The cosmetic method according to any one of claims 4 to 9, wherein the waterproof moisture-permeable layer is at least one selected from the group consisting of an oil layer containing at least one of vaseline and liquid paraffin, a polylactic acid layer, and artificial skin.

11. The cosmetic method according to any one of claims 1 to 10, wherein when the moisturizing polyvinyl alcohol film or the laminate comprising the moisturizing polyvinyl alcohol film and the waterproof moisture-permeable layer is evaluated by a moisture evaporation test, an amount of water evaporation when measured in an environment of 23 ℃ 40% RH is less than an amount of water evaporation when measured in an environment of 28 ℃ 70% RH.