Humidity regulator and humidity-responsive film-forming composition containing said regulator

Abstract

Provided are: a humidity regulator that contains a naturally derived component and that could be used to prepare a film exhibiting humidity responsiveness similar to that of a polyvinyl alcohol film, which is a petroleum-derived synthetic polymer; and a humidity-responsive film-forming composition containing said regulator.　A humidity regulator according to the present disclosure contains a polysaccharide, and a humidity-responsive film-forming composition according to the present disclosure contains said humidity regulator.

Description

Humidity adjuster and humidity-responsive film-forming composition containing said adjuster

[0001] The present disclosure relates to a humidity adjusting agent and a humidity-responsive film-forming composition containing the adjusting agent.

[0002] BACKGROUND ART In recent years, films and the like having moisture permeability have been used in various fields.

[0003] Patent Document 1 discloses a moisture-permeable film for use in clothing and the like, which contains a matrix resin and collagen powder made of cross-linked regenerated collagen, and has a porosity of 1 to 95%.

[0004] Patent Document 2 discloses a wound bed environment adjusting sheet that uses a moisture-permeable hydrogel sheet and is applied to a skin wound area.

[0005] Patent Document 3 discloses a moisturizing film cosmetic containing a polyvinyl alcohol film.

[0006] Patent Document 4 discloses an emulsion cosmetic comprising an aqueous phase containing water and polyvinyl alcohol, and an oil phase containing oil, wherein the content of polyvinyl alcohol is 0.5 mass% or more relative to the total amount of the emulsion cosmetic.

[0007] JP 2010-077202 A International Publication No. 2012 / 036064 International Publication No. 2021 / 002124 International Publication No. 2022 / 130964

[0008] The present inventors have developed cosmetics and the like having humidity-responsive properties that can reduce sticky discomfort in high-humidity environments or when sweating, while moisturizing the skin in low-humidity environments and exhibiting beauty effects, as described in Patent Documents 3 and 4. However, the main ingredient used in such cosmetics is polyvinyl alcohol, a synthetic polymer derived from petroleum, and there has been a demand for the use of environmentally friendly, naturally derived ingredients.

[0009] It should be noted that the moisture-permeable films and gel sheets having moisture-permeable properties described in Patent Documents 1 and 2 are always in a moisture-permeable state, and therefore do not exhibit humidity responsiveness as described in Patent Documents 3 and 4.

[0010] Therefore, the subject matter of the present disclosure is to provide a humidity regulator containing naturally derived ingredients, which can be used to prepare a film exhibiting humidity responsiveness similar to that of a polyvinyl alcohol film, a synthetic polymer derived from petroleum, and a humidity-responsive film-forming composition containing the regulator.

[0011] <Aspect 1> A humidity regulator comprising a polysaccharide. <Aspect 2> The regulator according to Aspect 1, wherein the polysaccharide comprises at least one selected from the group consisting of xanthan gum, hydroxypropyl methylcellulose, hydroxypropyl cellulose, stearoxyhydroxypropyl methylcellulose, hydroxyethyl cellulose, polyoctanium-10, guar hydroxypropyltrimonium chloride, and pullulan. <Aspect 3> A composition for forming a humidity-responsive film, comprising the regulator according to Aspect 1 or 2. <Aspect 4> The composition according to Aspect 3, wherein a humidity-responsive film formed from the composition exhibits a humidity responsiveness of greater than 1.00. <Aspect 5> The composition according to Aspect 3 or 4, wherein the content of the polysaccharide is 1.0% by mass or more. <Aspect 6> The composition according to any one of Aspects 3 to 5, comprising at least one selected from the group consisting of erythritol, trehalose, citric acid, 4-methoxysalicylic acid or a salt thereof, and niacinamide. Aspect 7: The composition according to Aspect 6, wherein the mass ratio of the total amount of the at least one selected from the group consisting of erythritol, trehalose, citric acid, 4-methoxysalicylic acid or a salt thereof, and niacinamide to the polysaccharide is 0.01 or more. Aspect 8: The composition according to any one of Aspects 3 to 7, which is a cosmetic. Aspect 9: A method of using a polysaccharide as a humidity adjuster. Aspect 10: A method of using a composition containing a humidity adjuster including a polysaccharide as a humidity-responsive film-forming composition.

[0012] According to the present disclosure, it is possible to provide a humidity regulator containing naturally derived components, which can be used to prepare a film exhibiting humidity responsiveness similar to that of polyvinyl alcohol film, a synthetic polymer derived from petroleum, and a humidity-responsive film-forming composition containing the regulator.

[0013] Figure 1 is a graph showing humidity response performance when various polysaccharides are used. Figure 2 is a graph evaluating components that affect humidity response when used in combination with polysaccharides. Figure 3 is a graph evaluating the influence of humidity response-improving components on various polysaccharides. Figure 4 is a schematic diagram of a measurement specimen sealed with a measurement sample, used when measuring transmittance.

[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present disclosure is not limited to the following embodiments, and various modifications can be made within the scope of the present invention.

[0015] The humidity adjuster of the present disclosure includes a polysaccharide, and the humidity-responsive film-forming composition of the present disclosure includes the humidity adjuster.

[0016] Without being limited by theory, it is believed that the principle of action that polysaccharides can be used as humidity adjusters and that films obtained from compositions containing such humidity adjusters can exhibit humidity responsiveness is as follows.

[0017] Polyvinyl alcohol (hereinafter, sometimes referred to as "PVA") used in Patent Document 3 and other documents is generally known to have excellent affinity with moisture. According to Patent Document 3, as shown in FIG. 1 of Patent Document 3, when a PVA film 101 is applied to the skin, moisture 105 evaporated from the skin binds to PVA molecules 103 in the film, and the PVA molecules 103 move in an attractive manner around the moisture 105, thereby forming gaps 107 through which moisture can pass. Therefore, in a low-humidity environment, the PVA molecules 103 do not move near the outermost surface of the PVA film 101, and therefore the gaps 107 through which moisture can pass are not formed. On the other hand, as shown in FIG. 2 of Patent Document 3, in a high-humidity environment, the PVA molecules 203 near the outermost surface of the PVA film 201 also move in an attractive manner around the moisture 205, thereby forming gaps 207 through which moisture can pass throughout the entire thickness of the film. As a result, it was thought that PVA film exhibits the ability to change the amount of water evaporation in response to changes in the humidity environment, i.e., "humidity responsiveness."

[0018] Further research by the present inventors has revealed that, under the influence of moisture, PVA films produce portions exhibiting a crystalline structure formed by a regular arrangement of PVA molecules, and amorphous portions that do not exhibit a crystalline structure. It has also been found that portions exhibiting a crystalline structure exhibit the ability to inhibit moisture permeation, while amorphous portions that do not exhibit a crystalline structure exhibit the ability to allow moisture permeation. Thus, it has been revealed that the structural balance between amorphous portions and crystalline portions that can be produced under the influence of moisture contributes to humidity responsiveness.

[0019] The inventors believe that the crystallization in PVA films is due to the action of hydrogen bonds associated with the hydroxyl groups of PVA. Therefore, assuming that the crystalline structure associated with the hydroxyl groups of PVA contributes to humidity responsiveness, they conducted a material selection process, assuming that naturally occurring components that have hydroxyl groups and can exhibit a crystalline structure would also be capable of exhibiting humidity responsiveness. As a result, the inventors discovered that, among various naturally occurring components, polysaccharides can be used to form films that exhibit humidity responsiveness similar to PVA films, and that these polysaccharides can be used as humidity regulators. It is believed that films prepared using polysaccharides can exhibit humidity responsiveness because, due to the influence of moisture, amorphous regions and crystalline regions can be generated, similar to PVA films.

[0020] The definitions of terms used in this disclosure are as follows:

[0021] In the present disclosure, "humidity responsiveness" refers to the ability to change the amount of water evaporation in response to changes in the humidity environment, specifically, the ability to make the amount of water evaporation in a low humidity environment less than the amount of water evaporation in a high humidity environment. For example, the "humidity responsiveness" in the present disclosure can be evaluated by the value of the transmittance at atmospheric pressure, 28°C, and 70% relative humidity relative to the transmittance at atmospheric pressure, 28°C, and 30% relative humidity using a film prepared by the method described below.

[0022] In the present disclosure, a "low humidity environment" refers to an environment in which the relative humidity at atmospheric pressure and 28° C. is less than 50% RH, 45% RH or less, 40% RH or less, 35% RH or less, 30% RH or less, 25% RH or less, or 20% RH or less. There is no particular restriction on the lower limit of the relative humidity, but it can be, for example, 3% RH or more, 5% RH or more, 7% RH or more, or 10% RH or more. Furthermore, such relative humidity can be converted into, for example, weight absolute humidity, which is not affected by temperature, and the weight absolute humidity can be 8.7 g / kg or less, 7.9 g / kg or less, 7.0 g / kg or less, 6.1 g / kg or less, 5.4 g / kg or less, 5.2 g / kg or less, 5.0 g / kg or less, or 4.8 g / kg or less, or 0.52 g / kg or more, 0.86 g / kg or more, 1.2 g / kg or more, or 1.7 g / kg or more.

[0023] In the present disclosure, a "high humidity environment" refers to an environment in which the relative humidity at atmospheric pressure and 28°C is 50% RH or higher, 55% RH or higher, 60% RH or higher, 65% RH or higher, 70% RH or higher, or 75% RH or higher. There is no particular limitation on the upper limit of this relative humidity, but it can be, for example, 100% RH or lower or less than 100% RH. Furthermore, this relative humidity can be converted, for example, into weight absolute humidity that is not affected by temperature, and the weight absolute humidity can be 12 g / kg or higher, 13 g / kg or higher, 14 g / kg or higher, 15 g / kg or higher, 17 g / kg or higher, or 18 g / kg or higher, or 24 g / kg or lower or less than 24 g / kg.

[0024] In this disclosure, "film" includes not only films that can be carried alone, such as wrap film, but also thin films that cannot be carried alone, such as coating films. Here, in this disclosure, films that can be carried alone, such as wrap film, can be distinguished as "self-supporting films," and thin films that cannot be carried alone can be distinguished as "non-self-supporting films."

[0025] In the present disclosure, "beauty" or "beauty method" means applying the humidity-responsive film-forming composition of the present disclosure to a target area (e.g., a body surface) to beautify the condition of the target area or a method for beautifying the condition of a body surface, and is different from methods of surgery, treatment, or diagnosis of humans.

[0026] In this disclosure, "body surface" means the skin surface of the body.

[0027] The humidity adjuster of the present disclosure includes a polysaccharide. As described above, a film obtained using the polysaccharide can exhibit humidity responsiveness, i.e., has the ability to control humidity, and therefore, it can be said that the polysaccharide can be used as a humidity adjuster.

[0028] The amount of polysaccharide in the humidity regulator is not particularly limited and may be, for example, 5.0% by mass or more, 10% by mass or more, 30% by mass or more, 50% by mass or more, 70% by mass or more, 80% by mass or more, or 90% by mass or more, or may be 100% by mass or less, or less than 100% by mass, relative to the total amount of the humidity regulator. The polysaccharide can be incorporated as appropriate within such ranges.

[0029] <Polysaccharides> There are no particular limitations on the polysaccharides as long as they can form a film. In the present disclosure, the term "polysaccharide" refers to a general term for long chains of monosaccharides (e.g., glucose, mannose, etc.), and more specifically, refers to carbohydrates composed of 5 or more, 8 or more, 10 or more, or 15 or more monosaccharides linked together. In the present disclosure, the term "polysaccharide" encompasses not only polysaccharides but also their derivatives. Examples of polysaccharide derivatives include water-soluble alkyl-substituted polysaccharide derivatives. Polysaccharides can be used alone or in combination.

[0030] As the polysaccharide, for example, polysaccharides exhibiting nonionic, cationic, or anionic properties can be used. Among them, nonionic and cationic polysaccharides are preferred from the viewpoints of film-forming properties, humidity responsiveness, etc.

[0031] Specific examples of polysaccharides include at least one selected from the group consisting of sodium hyaluronate, agar, sodium alginate, xanthan gum, hydroxypropyl methylcellulose, hydroxypropyl cellulose, stearoxyhydroxypropyl methylcellulose, hydroxyethyl cellulose, polyoctanium-10, guar hydroxypropyltrimonium chloride, and pullulan. Among these, from the viewpoints of film-forming ability and humidity responsiveness, xanthan gum, hydroxypropyl methylcellulose, hydroxypropyl cellulose, stearoxyhydroxypropyl methylcellulose, hydroxyethyl cellulose, polyoctanium-10, guar hydroxypropyltrimonium chloride, and pullulan are preferred, hydroxypropyl methylcellulose, hydroxypropyl cellulose, stearoxyhydroxypropyl methylcellulose, hydroxyethyl cellulose, and guar hydroxypropyltrimonium chloride are more preferred, hydroxypropyl cellulose and guar hydroxypropyltrimonium chloride are even more preferred, and hydroxypropyl cellulose is particularly preferred. From the viewpoint of humidity responsiveness, etc., these components are preferably contained in an amount of 50% by mass or more, more than 50% by mass, 60% by mass or more, 70% by mass or more, 80% by mass or more, or 90% by mass or more relative to the total amount of polysaccharides used. There is no particular upper limit to the amount used, and it can be, for example, 100% by mass or less or less than 100% by mass.

[0032] <Optional Components> In addition to polysaccharides, the humidity regulator of the present disclosure can contain various additives as long as they do not adversely affect the effects of the present invention. Specific examples of optional components include moisturizers, water-soluble polymers, oil-soluble polymers, sequestering agents, neutralizing agents, surfactants, lower alcohols, various extracts, UV absorbers, skin nutrients, vitamins, water-soluble agents applicable to pharmaceuticals, quasi-drugs, cosmetics, etc., antioxidants, buffers, preservatives, antioxidant assistants, dispersants, propellants, pigments, pearling agents, dyes, coloring materials, fragrances, water, oils, acid components, and alkaline components. The optional components can be used alone or in combination of two or more.

[0033] <<Composition for forming a humidity-responsive film>> The composition for forming a humidity-responsive film of the present disclosure includes the humidity adjuster described above. A composition containing the humidity adjuster of the present disclosure, which includes the polysaccharide described above, can form a humidity-responsive film, and therefore, it can be said that such a composition can be used as a composition for forming a humidity-responsive film (sometimes simply referred to as a "composition").

[0034] For example, when the composition of the present disclosure is applied to a target site (e.g., a body surface or wall) to form a film, the composition can exhibit humidity responsiveness at the application site. As described in the humidity responsiveness test described below, such humidity responsiveness can be evaluated based on the value of the permeability at atmospheric pressure and 70% relative humidity at 28°C relative to the permeability at atmospheric pressure and 30% relative humidity at 28°C. Note that these two permeabilities can be determined from the regression line obtained from a graph plotting permeability values ​​at several relative humidities versus relative humidity, with permeability on the Y-axis and relative humidity on the X-axis, as described below.

[0035] <Method for Measuring Permeability> The permeability was measured by measuring the area of ​​the open end (radius: 0.7 cm, area: 1.54 cm) of a vial into which 12 mL of water had been poured, as shown in FIG. ２ ) is covered with a film of a measurement sample prepared using the composition, and left to stand in a low humidity environment of, for example, 28°C and 30% RH until it reaches an equilibrium state where the amount of evaporation is at least approximately constant over time. Then, the water loss rate can be calculated using the following formulas 1 and 2. Note that the value of permeability in the present disclosure is intended to be the average value of three or more measurements: Water loss rate (g / m ２ ・h) = (w １ -w ０ ) / (Surface area x time) ...Formula 1 Transmittance (g / m ２ · h · Pa) = Water loss rate / (P ｉｎｓｉｄｅ -P ｏｕｔｓｉｄｅ )...Equation 2

[0036] w in Equation 1 １ and w ０are the weights (g) of the measurement sample before and after the test, respectively, and the surface area is the surface area (m ２ ) and time is intended to be the measurement time (h) of the amount of water evaporation in an equilibrium state. ｉｎｓｉｄｅ and P ｏｕｔｓｉｄｅ are intended to mean the internal pressure (Pa) inside the vial, where the relative humidity can be assumed to be 100%, and the external pressure (Pa) under the set humidity environment, respectively.

[0037] The measurement sample film was prepared by mixing polysaccharide and ion-exchanged water in a 10 mL vial and stirring them so that the polysaccharide concentration was 5% by mass. The resulting composition was then poured into a 19.6 cm2 film. ２ The mixture is then dried to prepare a film having a thickness of about 60 μm.

[0038] A film (sometimes simply referred to as a "film") prepared using the composition of the present disclosure can exhibit humidity responsiveness such that, for example, the transmittance when measured in a low-humidity environment of 28°C and 30% RH is less than the transmittance when measured in a high-humidity environment of 28°C and 70% RH. In contrast, when an open system or a vial is covered with a simple moisture-permeable member such as filter paper, the transmittance when measured in a low-humidity environment of 28°C and 30% RH is approximately equal to the transmittance when measured in a high-humidity environment of 28°C and 70% RH.

[0039] The composition of the present disclosure can exhibit a humidity response of more than 1.00 or 1.05 or greater, preferably 1.10 or greater or 1.15 or greater, more preferably 1.20 or greater or 1.25 or greater, in terms of humidity response measured using the transmittance described above in a film prepared using the composition. The upper limit of the humidity response is not particularly limited, and can be, for example, 2.00 or less, 1.90 or less, or 1.80 or less.

[0040] In addition, when the measurement environment is an environment with a lower humidity than an environment of, for example, 28°C and 30% RH, a film prepared using the composition of the present disclosure can further suppress evaporation of moisture. Therefore, the humidity responsiveness value using the above-mentioned transmittance tends to increase as the difference in humidity environment of the measurement atmosphere increases.

[0041] The humidity-responsive film-forming composition of the present disclosure contains a polysaccharide that can function as a humidity regulator. The amount of polysaccharide to be added varies depending on the formulation of the composition, and is not particularly limited as long as it is a concentration that allows the formation of a humidity-responsive film. The amount can be, for example, 1.0% by mass or more, 5.0% by mass or more, 10% by mass or more, 20% by mass or more, 30% by mass or more, 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, or 90% by mass or more, relative to the total amount of the composition. It can also be 100% by mass or less, less than 100% by mass, 90% by mass or less, 80% by mass or less, 70% by mass or less, 60% by mass or less, 50% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, or 10% by mass or less. The polysaccharide can be added appropriately within these ranges.

[0042] <Form, shape, and use of the composition> The form of the composition of the present disclosure is not particularly limited, and may be, for example, a single phase, or an oil-in-water or water-in-oil emulsion. These can be appropriately prepared by conventional methods. Here, in the present disclosure, the term "single phase" refers to a single phase essentially composed of an aqueous phase. Here, "substantially" means that, for example, oil (e.g., an oil-soluble UV absorber) may be solvated or solubilized with alcohol or the like and incorporated into the aqueous phase to a small extent, but does not include oil droplets (emulsified particles) emulsified with a surfactant or the like, as contained in an oil-in-water emulsion composition.

[0043] The form of the composition of the present disclosure is not particularly limited, and examples thereof include liquid, emulsion, cream, gel, mist, spray, aerosol, mousse, and the like.

[0044] In some embodiments, the composition of the present disclosure can be used as a cosmetic. In this case, the product form of the composition (cosmetic) is not particularly limited, and examples thereof include skin care cosmetics such as emulsion, cream, face oil, body oil, and serum; makeup cosmetics such as foundation, makeup base, lipstick, blush, eye shadow, mascara, and mascara base; and sunscreen cosmetics. As described in the section on beauty methods below, the composition of the present disclosure can exhibit excellent beauty effects such as improving skin sweatiness and moisturizing effects, and therefore can be suitably used as a cosmetic.

[0045] In addition, since the composition of the present disclosure produces a film that is humidity responsive, it can also be used for applications other than cosmetics, particularly applications that require humidity responsiveness. Examples of such applications include medical applications (e.g., adhesive bandages and medical tapes), clothing applications, construction applications (e.g., wallpaper), and agricultural applications (e.g., greenhouses or plant cultivation). When using the composition of the present disclosure in such applications, the composition may be applied to a moisture-permeable substrate, or a film formed using the composition may be used as is or laminated to a moisture-permeable substrate.

[0046] <Optional Components> Various components can be appropriately blended into the composition of the present disclosure within the range that does not adversely affect the effects of the present invention. Examples of such components include humidity response improvers, humectants (e.g., 1,3-butylene glycol, propylene glycol, dynamite glycerin, etc.), surfactants (anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants), water-soluble polymers, rubber, elastomers, pressure-sensitive adhesives, adhesives, adhesion modifiers, adhesion modifiers, UV absorbers, antioxidants, preservatives, antioxidant aids, crosslinking agents, light diffusing agents, fillers, neutralizing agents, lower alcohols such as ethanol, polyhydric alcohols such as PEG 6000 and dipropylene glycol, higher alcohols such as batyl alcohol, various extracts, sugars, amino acids, organic amines, polymer emulsions, chelating agents, UV scattering agents, pH adjusters, skin nutrients, vitamins, various agents applicable to pharmaceuticals, quasi-drugs, cosmetics, etc., buffers, preservatives, antioxidant aids, thickeners, dispersants, propellants, usable powders, pigments, dyes, coloring materials, fragrances, water, oils, acid components, and alkaline components. The optional components may be used alone or in combination of two or more.

[0047] (Humidity Response Improver) The optional component "humidity response improver" of the present disclosure refers to an agent that improves the humidity response performance of a film prepared using a composition obtained by incorporating the agent into a composition containing a polysaccharide of the present disclosure, compared to a film prepared using a composition that does not contain the agent. Specific examples of such humidity response improvers include at least one selected from the group consisting of erythritol, trehalose, citric acid, 4-methoxysalicylic acid or a salt thereof, and niacinamide. Of these, 4-methoxysalicylic acid or a salt thereof is preferred. Here, citric acid does not include citrate salts such as sodium citrate. Furthermore, examples of salts of 4-methoxysalicylic acid include the sodium salt and potassium salt.

[0048] From the viewpoint of improving the humidity responsiveness of the obtained film, the amount of humidity responsiveness improver used is preferably such that the mass ratio of humidity improver (e.g., the total amount of at least one selected from the group consisting of erythritol, trehalose, citric acid, 4-methoxysalicylic acid or a salt thereof, and niacinamide) to polysaccharide is 0.01 or more or 0.05 or more, more preferably 0.06 or more or 0.08 or more, and even more preferably 0.1 or more, 0.2 or more, 0.3 or more, 0.4 or more, or 0.5 or more. The upper limit of this mass ratio can be, for example, 10 or less, 5 or less, 3 or less, 1 or less, 0.9 or less, 0.8 or less, 0.7 or less, 0.6 or less, or 0.5 or less.

[0049] It is believed that films prepared using polysaccharides may exhibit humidity responsiveness because, like PVA films, amorphous regions and crystalline regions may be formed due to the influence of moisture. These crystalline regions may be affected by anionic components. Therefore, anionic components may be incorporated into the composition as long as they do not adversely affect the effects of the present invention. However, from the viewpoint of humidity responsiveness, the amount of anionic components, such as anionic surfactants, incorporated is preferably 10% by mass or less, 5.0% by mass or less, 1.0% by mass or less, 0.5% by mass or less, 0.1% by mass or less, 0.05% by mass or less, or 0.01% by mass or less, based on the total amount of the composition. It is more preferable that the composition does not contain any anionic components.

[0050] <<Humidity-Responsive Film>> The composition of the present disclosure can provide a film that exhibits humidity responsiveness as described above.

[0051] <Thickness> The thickness of a film prepared using the composition of the present disclosure is not particularly limited and can be appropriately adjusted depending on the location where the composition of the present disclosure is applied, the purpose of use, the balance of humidity responsiveness when combined with a waterproof and moisture-permeable layer described below, etc. The film thickness can be, for example, 1 mm or less, 500 μm or less, 300 μm or less, 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, 0.5 μm or less, or 0.1 μm or less, or 0.01 μm or more, 0.05 μm or more, 0.1 μm or more, 0.5 μm or more, or 1 μm or more. In particular, when used in combination with a waterproof and moisture-permeable layer described below, the thickness of the film can be as thin as 100 μm or less, 70 μm or less, 50 μm or less, 40 μm or less, 30 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, 0.7 μm or less, or 0.5 μm or less, or can 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.

[0052] When the film is a freestanding film, the thickness can be defined as the average value calculated by measuring the thickness of any portion of the film at least five times using a high-precision Digimatic Micrometer (MDH-25MB, manufactured by Mitutoyo Corporation). When the film thickness is too thin to be measured with a high-precision Digimatic Micrometer, the film thickness can be determined by a similar method using a scanning electron microscope as described below.

[0053] For example, when the film has a laminated structure including a film prepared using the composition of the present disclosure and a waterproof / moisture-permeable layer described below, and the waterproof / moisture-permeable layer cannot be separated, a cross section of the laminated structure in the thickness direction is measured using a scanning electron microscope. The average thickness of at least five arbitrary locations on the film in the laminated structure can then be defined as the thickness of the film.

[0054] <Basis Weight> The film can also be specified by basis weight instead of thickness. Here, basis weight in the present disclosure is the weight per 1 cm of film. ２ The basis weight of the film can be defined as the weight (mg) per unit area. ２ Above, 0.0060mg / cm ２ Above, 0.010mg / cm ２ Above, 0.025mg / cm ２ Above, 0.035mg / cm ２ Above, 0.050mg / cm ２ Above, 0.070mg / cm ２ Above, 0.10mg / cm ２ Above, 0.15mg / cm ２ Above, 0.30mg / cm ２ Above, 0.45mg / cm ２ Above, 0.70mg / cm ２ Above, 1.0mg / cm ２ Above, 3.0mg / cm ２ Above, 5.0mg / cm ２ Above, 7.0mg / cm ２ or more, or 10 mg / cm ２ and 100 mg / cm or more. ２ Below, 50.0mg / cm ２ Below, 30.0mg / cm ２ Below, 10.0mg / cm ２ Below, 12.0mg / cm ２ Below, 8.5mg / cm ２ Below, 6.0mg / cm ２ Below, 4.5mg / cm ２ Below, 2.5mg / cm ２ Below, 2.0mg / cm ２ Below, 1.5mg / cm ２ Below, 1.2mg / cm ２ Below, 1.0mg / cm ２ Below, 0.80mg / cm ２ Below, 0.60mg / cm ２ Below, 0.35mg / cm ２ Below, 0.15mg / cm ２ Below, 0.10mg / cm ２ Below, 0.085mg / cm２ or less, or 0.060 mg / cm ２ It can be as follows:

[0055] <Applications> Films prepared using the composition of the present disclosure, and films laminated with, for example, a moisture-permeable substrate and / or an optional waterproof / moisture-permeable layer described below, can exhibit humidity responsiveness and can be used in a variety of applications.

[0056] Examples of uses for such films include cosmetics, medical uses (e.g., adhesive bandages and medical tapes), clothing uses, construction uses (e.g., wallpaper), and agricultural uses (e.g., films for greenhouses or plant cultivation).

[0057] <Optional Constituent Layer> The humidity-responsive film of the present disclosure may contain any constituent layer as long as it does not adversely affect the effects of the present invention. In addition to the moisture-permeable substrate and waterproof / moisture-permeable layer described above, such constituent layers may include, for example, a moisture-permeable pressure-sensitive adhesive layer (e.g., a pressure-sensitive adhesive layer having through holes), a protective film with release properties, and a release sheet. The optional constituent layers may be used alone or in combination of two or more. For example, a protective film may be applied to one side of the humidity-responsive film and / or a release sheet may be applied to the opposite side. Here, the surfaces of the protective film and the release sheet may be subjected to a release treatment such as silicone. Furthermore, the release properties of the protective film and the release sheet relative to the humidity-responsive film may be the same or different. From the viewpoint of ease of peeling from the humidity-responsive film, it is preferable that their release properties are different.

[0058] The material of the optional constituent layer is not particularly limited, and examples thereof include polyolefins such as polyethylene and polypropylene, polyesters such as polyethylene terephthalate, cotton, paper, etc. The optional constituent layer may be in the form of, for example, a film, or a nonwoven fabric, a knitted fabric, a woven fabric, etc.

[0059] <<Method for producing humidity-responsive film>> The humidity-responsive film can be produced using the above-mentioned composition for forming a humidity-responsive film. The production method is not particularly limited, and for example, the composition can be applied to a release sheet or a moisture-permeable substrate by any known coating method, such as offset printing, gravure coating, bar coating, knife coating, or spray coating, and the film can be continuously produced by optionally employing, for example, a drying step, a step of applying any constituent layer, a winding step, or the like.

[0060] The humidity-responsive film can also be produced discontinuously using the humidity-responsive film-forming composition described above. For example, a predetermined amount of the composition is added to a container or mold, and dried to prepare a film. If necessary, an optional constituent layer can be applied to the resulting film to produce the humidity-responsive film. Alternatively, the composition can be placed in, for example, a tube container or a spray container, and applied from the container to a target site (e.g., a body surface or wall) and dried to form a humidity-responsive film directly on the target site.

[0061] <<Kit>> The humidity-responsive film-forming composition of the present disclosure can be provided as a kit including the composition and any optional components.

[0062] <Optional Components> Optional components that can be included in the kit are not particularly limited, and examples include components to which a waterproof / moisture-permeable layer can be applied, a brush, a roller, a cutter, scissors, a mirror, etc. The optional components can be provided in the kit either alone or in combination of two or more.

[0063] (Components to which waterproof / moisture-permeable layer can be applied) In the present disclosure, a "waterproof / moisture-permeable layer" is a layer that has waterproof properties and moisture permeability, and does not exhibit humidity responsiveness by itself.

[0064] For example, if the film formed from the composition is thin and the area to which the film is applied (e.g., body surface or wall) has a high moisture content, evaporation of moisture into the outside air may not be suppressed even in a low-humidity environment. In such cases, by applying a waterproof / moisture-permeable layer between the film and the application area (e.g., body surface or wall), evaporation of moisture into the outside air can be suppressed and performance such as moisture retention can be ensured.

[0065] Furthermore, if the film becomes thicker, the rigidity of the film itself increases, which may make it difficult to apply the film to the area where it is to be applied, such as the skin, and may result in a poor appearance. Even if the waterproof / moisture-permeable layer is relatively thin, when combined with the film, it can provide sufficient humidity responsiveness, allowing the overall thickness to be reduced. As a result, a configuration that combines a waterproof / moisture-permeable layer with a thin film can improve, for example, applicability to the skin and appearance, compared to when a thick film is used.

[0066] Since the outermost surface of the film is the surface used to adjust the moisture permeability to the external environment, it is preferable that any of the above-mentioned constituent layers (e.g., waterproof moisture-permeable layer or protective film) is not formed on this surface. Therefore, for example, when a waterproof moisture-permeable layer is laminated on a humidity-responsive film and the resulting film is applied to the body surface or the like, it is preferable that the waterproof moisture-permeable layer is configured to be positioned closer to the body surface than the humidity-responsive film.

[0067] The waterproof / moisture-permeable layer may have a single layer structure or a laminate structure. The waterproof / moisture-permeable layer may be in the form of a free-standing or non-free-standing film. The waterproof / moisture-permeable layer may be configured to be applied to the entire surface or a portion of the humidity-responsive film.

[0068] The waterproof / moisture-permeable layer is not particularly limited as long as it is a layer that can exhibit the above-described humidity responsiveness when combined with the film formed from the composition. Examples of the waterproof / moisture-permeable layer include at least one selected from an oil layer, a polylactic acid layer, and an artificial skin.

[0069] Examples of materials for the oil layer include polar oils such as ester oils and non-polar oils such as hydrocarbon oils, among which non-polar oils are preferred from the viewpoint of humidity responsiveness.

[0070] Examples of non-polar oils include petrolatum, liquid paraffin, tetraisobutane, hydrogenated polydecene, olefin oligomer, isododecane, isohexadecane, squalane, polybutene, hydrogenated polybutene, polyisobutene, and hydrogenated polyisobutene. The non-polar oils can be used alone or in combination. Among them, petrolatum and liquid paraffin are preferred from the viewpoint of humidity responsiveness.

[0071] Materials that can be used to form the artificial skin include rubbers or elastomers such as urethane rubber, olefin rubber, silicone rubber, acrylic rubber, and natural rubber, as well as α-gel. These can be used alone or in combination of two or more. Among these, silicone rubber is preferred from the viewpoints of flexibility, humidity responsiveness, etc.

[0072] b. Thickness The thickness of the waterproof / moisture-permeable layer is not particularly limited, and can be adjusted appropriately depending on the location where the waterproof / moisture-permeable layer is applied, the purpose of use, and the balance of humidity responsiveness when combined with the above-mentioned humidity-responsive film.

[0073] The waterproof / moisture-permeable layer can also be specified by, for example, basis weight. The basis weight of the waterproof / moisture-permeable layer is, for example, 1.0 mg / cm ２ Above, 1.2mg / cm ２ or more, or 1.4 mg / cm ２ and 2.0 mg / cm or more. ２ Below, 1.8mg / cm ２ or less, or 1.6 mg / cm ２ It can be as follows:

[0074] d. Optional Components The waterproof / moisture-permeable layer of the present disclosure can contain various components as appropriate, provided they do not adversely affect the effects of the present invention. Examples of such components include humectants, polymers, rubbers, elastomers, pressure-sensitive adhesives, adhesives, adhesion modifiers, adhesion modifiers, UV absorbers, antioxidants, preservatives, antioxidant aids, light diffusers, fillers, skin nutrients, vitamins, various chemicals applicable to pharmaceuticals, quasi-drugs, cosmetics, etc., organic powders, pigments, dyes, coloring materials, and fragrances. The optional components can be used alone or in combination of two or more.

[0075] Cosmetic Method Using Humidity-Responsive Film-Forming Composition In some embodiments, the composition of the present disclosure can be used in a cosmetic method. This cosmetic method includes applying the composition of the present disclosure to a target site (e.g., a body surface). When applied to a target site, the composition of the present disclosure can form a humidity-responsive film on the surface. For example, such a film can release moisture from the skin to the outside air in a high-humidity environment and reduce or inhibit moisture evaporation from the skin in a low-humidity environment, thereby sufficiently moisturizing the skin even in a low-humidity environment. As a result, it is possible to reduce the discomfort of sweat-induced skin stuffiness or sticky feeling when sweating. Furthermore, it improves the skin's own production of moisturizing ingredients and improves turnover in the stratum corneum, thereby reducing skin problems such as rough skin and enhancing cosmetic effects. Furthermore, such a film can also effectively alleviate hair problems, such as split ends and breakage, in a low-humidity environment.

[0076] The means for applying the composition to the target site is not particularly limited, and can be, for example, by applying the composition to the target site. The means for applying the composition to the target site may be, for example, by spraying the composition onto the target site from a spray container containing the composition, or by putting the composition into a container without a spray function, taking an appropriate amount of the composition from the container onto a finger or the like, and spreading it over the target site.

[0077] In the cosmetic method of the present disclosure, instead of applying the composition to the target area, a film obtained from the composition may be directly attached to the target area.

[0078] <<Target Site>> The target site for application of the humidity-responsive film-forming composition of the present disclosure and the humidity-responsive film formed from the composition is not particularly limited, and they can be applied to a variety of sites. Examples of such target sites include sites made of materials such as resin, metal, concrete, ceramics, glass, wood, paper, and cloth. Sites made of such materials may be foamed or pore-formed to impart moisture permeability, as necessary. Other target sites include any part of the body. Examples of such sites include the skin surface of the face (lips, eyes, nose, cheeks, forehead, etc.), neck, ears, hands, arms, legs, feet, chest, abdomen, back, etc., as well as body hair such as hair, eyelashes, eyebrows, and beard. Here, skin also includes nails, which are hardened due to changes in the keratin layer of the skin's epidermis.

[0079] The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. Hereinafter, unless otherwise specified, the blending amounts are expressed in mass%. Furthermore, the evaluation methods described in the examples are not limited to the compositions described in the examples and films formed therefrom, but can also be used for the above-mentioned compositions and films formed therefrom.

[0080] <Evaluation Method> The following humidity response test was carried out using each test sample obtained by the manufacturing method described below, and the results are shown in Tables 1 to 3 and FIGS.

[0081] <Humidity Response Test> As shown in FIG. 4, the circular opening (radius: 0.7 cm, area: 1.54 cm) of a vial into which 12 mL of water was poured was ２) was capped with each measurement sample, and the vial was left standing in a thermostatic chamber under predetermined temperature and humidity conditions. After leaving the vial standing for 2 hours or more until the evaporation rate reached an equilibrium state where it was almost constant over time, the amount of water evaporation was measured after 10 hours or more had passed, and the transmittance under the environments of 28°C, 25% RH, 35% RH, 55% RH, 65% RH, and 75% RH was calculated using the following formulas 1 and 2. The transmittance was calculated by averaging the values ​​obtained from three measurements: Water loss rate (g / m ２ ・h) = (w １ -w ０ ) / (Surface area x time) ...Formula 1 Transmittance (g / m ２ · h · Pa) = Water loss rate / (P ｉｎｓｉｄｅ -P ｏｕｔｓｉｄｅ ) ...Equation 2 Here, w in Equation 1 １ and w ０ are the weights (g) of the measurement sample before and after the test, respectively, and the surface area is the surface area (m ２ ) and the time is the measurement time (h) of the amount of water evaporation in the equilibrium state. ｉｎｓｉｄｅ and P ｏｕｔｓｉｄｅ are the internal pressure (Pa) inside the vial where the relative humidity can be assumed to be 100%, and the external pressure (Pa) under the set humidity environment, respectively.

[0082] Next, a graph relating each of the obtained transmittance values ​​and relative humidity was created with transmittance on the Y axis and relative humidity on the X axis, and a regression line was obtained from the graph. From the transmittances at 70% RH and 30% RH obtained from this regression line, a value relating to humidity responsiveness was obtained using the following formula 3. Note that the higher this value is above 1.00, the more excellent the humidity responsiveness is: Humidity responsiveness = transmittance in a high humidity environment at 28°C and 70% RH / transmittance in a low humidity environment at 28°C and 30% RH ... formula 3

[0083] Test Example 1 Each sample in this test example was prepared according to the following method. In Test Example 1, the humidity response performance when various polysaccharides were used was investigated. The results are shown in Table 1 and Figure 1.

[0084] Comparative Example 1 Filter paper #5A manufactured by ADVANTEC Co., Ltd., having a diameter of 21 mm, was used as a measurement sample for Comparative Example 1.

[0085] Example 1 A composition for film production was prepared by mixing xanthan gum (a polysaccharide) and ion-exchanged water in a 10 mL vial and stirring the mixture so that the concentration of xanthan gum was 5.0% by mass. ２ 3.0 g of the sample was added to a roughly circular petri dish and dried, and the basis weight of the sample for measurement was about 7.6 mg / cm ２ A film of the above was prepared.

[0086] Examples 2 to 11 Measurement sample films were prepared in the same manner as in Example 1, except that the polysaccharides were changed as shown in Table 1. The basis weight of each of the obtained films was approximately 7.6 mg / cm. ２ It was.

[0087]

[0088] <Results> As is clear from the results in Table 1 and Figure 1, it was confirmed that the film prepared using the composition containing polysaccharide exhibited humidity responsiveness. These results also revealed that polysaccharides have the ability to regulate humidity. Therefore, it was also confirmed that polysaccharides can be used as humidity regulators.

[0089] Furthermore, from the results of Examples 1 to 5, 9 to 11, and 6 to 8, it was also confirmed that, among polysaccharides, nonionic and cationic polysaccharides are superior in humidity response performance.

[0090] Test Example 2 Each sample in this test example was prepared according to the following method. In Test Example 2, a component (sometimes simply referred to as the "test component") that improves humidity responsiveness when used in combination with a polysaccharide was investigated. The results are shown in Table 2 and FIG. 2. Note that the "mass ratio" in the tables of the present disclosure refers to the mass ratio of the test component (in the case of Table 3, the humidity responsiveness-improving component) to the polysaccharide. Furthermore, the "reference comparative example" in Table 2 and FIG. 2 refers to a sample that contains a polysaccharide and exhibits humidity responsiveness, and therefore would normally be considered an example, but in which the effect of improving humidity responsiveness could not be confirmed when the polysaccharide and the test component were used in combination.

[0091] Comparative Example 2 Filter paper #5A manufactured by ADVANTEC Co., Ltd., having a diameter of 21 mm, was used as a measurement sample for Comparative Example 2.

[0092] Control 1 (Evaluation Criteria) Hydroxypropyl cellulose (a polysaccharide) and ion-exchanged water were mixed in a 10 mL vial and stirred so that the concentration of hydroxypropyl cellulose was 5.0% by mass, to prepare a film-forming composition. ２ 3.0 g of the sample was added to a roughly circular petri dish and dried, and the basis weight of the sample for measurement was about 7.6 mg / cm ２ A film of the above was prepared.

[0093] Comparative Example 1 Hydroxypropyl cellulose, xylitol, and ion-exchanged water were mixed in a 10 mL vial and stirred so that the concentration of the polysaccharide hydroxypropyl cellulose was 5.0% by mass and the mass ratio of xylitol to the polysaccharide was 0.5, to prepare a film-forming composition. ２ 3.0 g of the sample was added to a roughly circular petri dish and dried, and the basis weight of the sample for measurement was about 7.6 mg / cm ２ A film of the above was prepared.

[0094] Comparative Example 2: A measurement sample film was prepared in the same manner as in Comparative Example 1, except that the amount of xylitol added was changed so that the mass ratio of xylitol to polysaccharides was 0.1. The basis weight of the obtained film was approximately 7.6 mg / cm. ２ It was.

[0095] Examples 12, 14, 16, 18, and 20 and Reference Comparative Example 3 Measurement sample films were prepared in the same manner as Reference Comparative Example 1, except that the components under investigation were changed to those listed in Table 2. The basis weight of the obtained films was approximately 7.6 mg / cm ２ It was.

[0096] Examples 13, 15, 17, 19, and 21 and Comparative Examples 4 and 5 Measurement sample films were prepared in the same manner as in Comparative Example 2, except that the components under investigation were changed to those listed in Table 2. The basis weight of each of the obtained films was approximately 7.6 mg / cm. ２ It was.

[0097]

[0098] <Results> As is clear from the results in Table 2 and FIG. 2, it was found that the components used in Examples 12 to 21 among the investigated components can further improve the humidity responsiveness effect when used in combination with a polysaccharide.

[0099] Test Example 3 Each sample in this test example was prepared according to the following method. Test Example 3 investigated whether the component (sometimes simply referred to as the "humidity responsiveness-improving component") that was found to have an effect of improving humidity responsiveness in Test Example 2 also has an effect on other polysaccharides. Here, the results of Comparative Example 2, Control 1, and Examples 12, 14, and 18 in Test Example 2 are also shown in Table 3 and Figure 3 for reference.

[0100] <Controls 2 and 3 (Evaluation Criteria)> Measurement sample films were prepared in the same manner as in Control 1, except that the polysaccharide was changed from hydroxypropyl cellulose to the components listed in Table 3. The basis weight of the obtained films was approximately 7.6 mg / cm. ２ It was.

[0101] Examples 22 to 25 Measurement sample films were prepared in the same manner as in Reference Comparative Example 1 in Test Example 2, except that the polysaccharide and the component under investigation were changed to the polysaccharide and humidity response improving component shown in Table 3. The basis weight of each of the obtained films was approximately 7.6 mg / cm. ２ It was.

[0102]

[0103] <Results> As can be seen from the results in Table 3 and FIG. 3, it was confirmed that the components capable of further improving humidity responsiveness, as revealed in Test Example 2, can also be effective for polysaccharides other than hydroxypropyl cellulose.

Claims

1. Humidity regulator containing polysaccharides.

2. The conditioning agent according to claim 1, wherein the polysaccharide comprises at least one selected from the group consisting of xanthan gum, hydroxypropyl methylcellulose, hydroxypropyl cellulose, stearoxyhydroxypropyl methylcellulose, hydroxyethyl cellulose, polyoctanium-10, guar hydroxypropyltrimonium chloride, and pullulan.

3. A humidity-responsive film-forming composition comprising the regulator according to claim 1 or 2.

4. The composition of claim 3, wherein a humidity responsive film formed by said composition exhibits a humidity responsiveness of greater than 1.

00.

5. The composition according to claim 3, wherein the content of said polysaccharide is 1.0% by mass or more.

6. The composition according to claim 3, comprising at least one member selected from the group consisting of erythritol, trehalose, citric acid, 4-methoxysalicylic acid or a salt thereof, and niacinamide.

7. The composition according to claim 6, wherein a mass ratio of the total amount of the at least one selected from the group consisting of erythritol, trehalose, citric acid, 4-methoxysalicylic acid or a salt thereof, and niacinamide to the polysaccharide is 0.01 or more.

8. The composition according to claim 3, which is a cosmetic preparation.

9. Using polysaccharides as humidity regulators.

10. A method of using a composition containing a humidity regulator including a polysaccharide as a humidity-responsive film-forming composition.

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