JP2005015480A - External application sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an external application sheet, when applied, hardly sticking to fingers, requiring no troublesome working such as wiping, cleaning and the like, hardly adhering to clothing, bedding and the like and hardly removed by the clothing, the bedding and the like, brought to contain a sufficient amount of urea and glycerol which are able to synergistically enhance effects for preventing the dry rough skin, hardly reducing barrier properties of the skin, and expressing sufficient moisture retention effect. <P>SOLUTION: The external application sheet has an ointment layer containing urea, and glycerol added if needed, and installed at least on one side of a support. Base materials constituting the ointment layer comprise an acrylic polymer obtained by polymerizing at least one species of monomers selected from acrylic acid, acrylic acid esters, methacrylic acid and methacrylic acid esters, a polyvinyl alcohol and a filler for enhancing aggregative force, added if needed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an external sheet. More specifically, the plaster layer contains urea and, if necessary, glycerin to prevent dry and rough skin, and to treat rough skin such as cracks and scratches. The present invention relates to a suitably used external sheet.

  Conventionally, urea, vitamin E, vitamin A, olive oil, squalane, rice bran, aloe and mugwort are known to have a rough skin treatment effect such as cracks and chapped skin. Lotions and ointments containing such ingredients And emulsions are commercially available.

  The following Patent Document 1 discloses a high-concentration urea-containing composition containing urea, a linear polyhydric alcohol, and water, and the following Patent Document 2 includes a skin moisturizing external preparation containing glycerin and urea. A composition is disclosed.

  However, the aforementioned lotions, ointments and emulsions, and drugs using the compositions described in Patent Documents 1 and 2 are liquid or semisolid such as ointments. Therefore, when the drug is spread on the rough skin, the drug tends to adhere to the fingers and give the user a sticky feeling. In addition, it takes time for wiping and washing, and after spreading on the affected area, it adheres to clothes and bedding and may contaminate them. In addition, the above effect may not be obtained because the above components are wiped off with clothes and bedding.

  In order to solve such a problem, Patent Document 3 below discloses a keratin improving sheet in which a plaster layer formed by blending a keratin improving agent is provided on the sheet. Patent Document 3 discloses that a keratin improving agent is blended in the plaster layer of the keratin improving sheet, and urea or glycerin may be blended in order to enhance the moisturizing effect.

  However, since urea has a hygroscopic property, when urea is added to the paste layer, the paste layer absorbs moisture due to moisture from the skin at the time of application. Therefore, the cohesive force of the adhesive constituting the base of the plaster layer is reduced, and adhesive residue may be generated on the skin at the time of peeling, or the plaster layer may be peeled off from the support. For this reason, there is a problem in that the required amount of urea cannot be blended, or when a sufficient amount of urea is blended, adhesive residue or back peeling occurs as described above, and the feeling of use is impaired. . Moreover, since glycerin has the effect | action which raises the moisturizing effect of urea synergistically, it is desirable to mix | blend with urea, but when glycerin is mix | blended with urea, the cohesive force of a paste layer will fall further, therefore Necessary amounts of urea and glycerin could not be blended.

On the other hand, Patent Document 4 below discloses a cosmetic gel sheet containing polyacrylic acid and / or polyacrylate, polyhydric alcohols, water and an external cross-linking agent as essential components. However, in such a water-containing gel sheet, moisture is required to maintain the shape as a sheet by crosslinking. Therefore, the above cosmetic gel sheet inevitably contains moisture, so that the skin keratin is excessively hydrated during use. Therefore, after the gel sheet is applied and peeled off, the hydrated skin stratum corneum is dried, so that the stratum corneum is cracked. Therefore, when the said gel sheet was used, there existed a problem that the skin barrier property fell conversely and rough skin was not fully improved.
JP-A-8-259442 JP 2001-226251 A JP-A-11-147820 Japanese Patent Laid-Open No. 11-228340

  The object of the present invention is to prevent sticking to fingers, clothes, bedding, etc. when applied to rough skin in view of the current state of the prior art described above, and to prevent active ingredients from being wiped away by clothes, bedding, etc. Although it is possible to obtain a sufficient moisturizing effect by containing a sufficient amount of urea and glycerin, it is unlikely to cause a decrease in cohesive force due to moisture absorption of the plaster layer. An object of the present invention is to provide a sheet for external use in which excessive hydration of the skin keratin is unlikely to occur and the skin barrier property after use is unlikely to decrease.

  As a result of intensive studies, the inventors of the present invention constituted a paste layer in an external sheet in which a paste layer containing urea, preferably urea and glycerin, was provided in the base on at least one side of the support. If the composition containing the polymer obtained by polymerizing at least one monomer selected from acrylic acid, acrylic acid ester, methacrylic acid and methacrylic acid ester, and polyvinyl alcohol is used as the base to The present inventors have found that the problems can be achieved and have made the present invention.

  That is, the present invention is an external sheet in which a plaster layer containing urea in a base is provided on at least one side of a support, wherein the base is acrylic acid, acrylic ester, methacrylic acid. And a sheet obtained by polymerizing at least one monomer selected from methacrylic acid ester and polyvinyl alcohol. Preferably, the plaster layer further contains glycerin.

  Preferably, a filler for improving cohesive strength is further added to the plaster layer. The filler for improving cohesive force is selected from the group consisting of, for example, zinc oxide, titanium oxide, white carbon, silicate, silicic acid, calcium carbonate, magnesium carbonate, calcium sulfate, barium sulfate, aluminum hydrate and the like. At least one kind is used.

  Moreover, in the external sheet which concerns on this invention, Preferably, it is comprised so that a paste layer may not contain water substantially.

  Details of the present invention will be described below.

  In the external sheet according to the present invention, urea is contained in the plaster layer as a medicinal component for treating rough skin.

  In this invention, it is preferable that urea is contained in the range of 0.1-25 weight% in the plaster layer, More preferably, it is 0.3-10 weight%. When the urea content is 0.1% by weight or more, the action of urea on the keratin is exhibited and the effect on rough skin is enhanced. In addition, the effect increases when the urea content is up to 25% by weight.

  In the present invention, preferably, glycerin can be further added to the plaster layer. Urea and glycerin act on human skin as moisturizers. In addition, urea and glycerin exhibit a function of maintaining a higher water content in the keratin due to a synergistic effect when used together than when used alone. In addition, the more moisture in the keratin, the higher the moisturizing effect, and the higher the rough skin preventing effect and the therapeutic effect. When blending glycerin, glycerin is preferably blended at a rate of 6 to 30% by weight of the plaster layer, more preferably 8 to 25% by weight. When the blending ratio of glycerin is 6% by weight or more, the action of glycerin on the keratin is exhibited and the effect on rough skin is enhanced. Moreover, the effect is large until the mixture ratio of glycerol is up to 30%. In addition, when the blending ratio of glycerin is in the range of 8 to 25% by weight, bleeding out hardly occurs on the surface of the plaster layer, and a more preferable sticking feeling can be obtained.

  The base of the plaster layer of the external sheet according to the present invention is a polymer obtained by polymerizing at least one monomer selected from acrylic acid, acrylic acid ester, methacrylic acid and methacrylic acid ester, and polyvinyl alcohol. And a filler for improving the degree of aggregation added as necessary.

  The polymer obtained by polymerizing at least one monomer selected from acrylic acid, acrylic acid ester, methacrylic acid and methacrylic acid ester is not particularly limited, but a polymer constituting a so-called acrylic emulsion adhesive is preferably used. Used. That is, in the present invention, preferably, the base includes an acrylic emulsion pressure-sensitive adhesive, polyvinyl alcohol, and a filler for improving the degree of aggregation added as necessary. In the present specification, the notation of (meth) acrylic acid is used to include acrylic acid and methacrylic acid, and the same applies to others.

  Acrylic emulsion adhesives are superior to solvent-based acrylic adhesives in terms of mixing stability with hydrophilic urea and glycerin, and are easy to adjust and control the adhesive performance. Is favorable, and is also advantageous in terms of health and safety. Further, compared to the case where an organic solvent-based or hot-melt adhesive is used, the emulsion adhesive does not need to be heated at the time of production, and therefore there is no risk that the rough skin prevention or treatment component is volatilized or dispersed.

  The acrylic emulsion pressure-sensitive adhesive has, as a main monomer, an alkyl (meth) acrylate such as n-butyl (meth) acrylate or 2-ethylhexyl (meth) acrylate in a dispersion medium containing water as a main component. (Meth) acrylic acid that can be copolymerized with a hydroxyl group-containing (meth) acrylate such as 2-hydroxyethyl (meth) acrylate as a sub-monomer, or by emulsion polymerization of the main monomer alone in a conventional manner, or It can be obtained by emulsion polymerization of a main monomer and a submonomer.

  Examples of commercial products of the acrylic emulsion pressure-sensitive adhesive include products such as those manufactured by Nippon Carbide Industries Co., Ltd., trade name: “Nicazole” series, manufactured by Nippon Acrylic Co., Ltd., trade name: “Primal” series, and the like. The acrylic emulsion pressure-sensitive adhesive is preferably used in a range of 40 to 94% by weight in the solid content in the plaster layer.

  In the present invention, polyvinyl alcohol is mixed with urea or urea and glycerin, which are hygroscopic components, to suppress cohesive failure when the plaster layer absorbs moisture due to sweating from the skin during use, or from the support. It is added to prevent peeling of the paste layer on the back surface and the adhesive layer remaining on the skin.

  Although it does not specifically limit as polyvinyl alcohol, Preferably, a thing with a polymerization degree of 1000 or more is used. The polyvinyl alcohol may be any one of partially saponified polyvinyl alcohol, intermediate saponified polyvinyl alcohol, and fully saponified polyvinyl alcohol, but polyvinyl alcohol having a saponification degree of 85 or more is preferably used. By setting the degree of polymerization to 1000 or more, when blended in the paste layer, the effect of suppressing the cohesive failure of the paste layer and the effect of suppressing the adhesive residue on the skin can be made sufficient. The blending amount is not particularly determined, but if it is too small, the desired cohesive force cannot be obtained, and if it is too much, the adhesive strength is lowered. Accordingly, the polyvinyl alcohol is preferably added to the plaster layer in the range of 0.1 to 20% by weight, and more preferably 0.3 to 10% by weight.

  The filler for improving the cohesive force added as necessary is used to further increase the cohesive force of the plaster layer. Examples of such a filler include zinc oxide, titanium oxide, white carbon, silicate, silicic acid, calcium carbonate, magnesium carbonate, calcium sulfate, barium sulfate, and aluminum hydrate. The addition amount of the filler is not particularly limited, but if it is too small, the effect of further increasing the cohesive force may not be obtained sufficiently, and if it is too large, the adhesive strength may be reduced. Therefore, it is preferable to add in the range of 0.05 to 5% by weight in the plaster layer, and it is more preferable to add the filler in the range of 0.1 to 1% by weight. Of these, zinc oxide, titanium oxide, white carbon and the like are preferable.

In the present invention, the plaster layer is preferably substantially free of water. The term “substantially free of water” specifically means that the water content per area of 1 m ^{2 of} the preparation in which the paste layer is bonded to the support is 1 g or less when measured by the method described herein. It shall be said. When the water content is adjusted to 1 g / m ² or less, it is desirable because it can effectively suppress a decrease in skin barrier properties.

  In the present invention, it is also possible to further mix components such as a pigment, a fragrance, a moisturizing extract, a keratin softener, and an ultraviolet absorber in the plaster layer.

In the present invention, the support is not particularly limited, and supports made of various materials conventionally used for plaster agents can be used as appropriate. However, in general, since the affixed portion is a bent portion such as a heel or an elbow, a support having flexibility is preferable. Examples of such a support include plastic films or sheets made of polyethylene, polyvinyl chloride, polyester, polyolefin, polyurethane, polyethylene terephthalate, ethylene-vinyl acetate copolymer, metal foil such as aluminum foil, non-woven fabric, woven fabric, and the like. Examples thereof include a cloth and a laminated film or sheet obtained by combining these. Furthermore, it is desirable that the moisture permeability of the support is 200 g / m ² · 24 hr or less. If the moisture permeability exceeds 200 g / m ² · 24 hr, it may be difficult to obtain a sufficient moisturizing effect.

  In the external sheet according to the present invention, it is preferable that release paper is laminated on the plaster layer in order to protect the adhesive layer until it is used. The release paper is peeled off from the plaster layer at the time of use. Therefore, any release paper having an appropriate release property can be used. As such a release paper, for example, a polyester film, high-quality paper, glassine paper, or the like coated with a silicone resin on one side or both sides is used.

  The manufacturing method of the external sheet according to the present invention is not particularly limited. For example, a solution for forming a paste layer containing urea, preferably urea and glycerin, is spread on a support and dried, or a solution for forming the paste layer is spread on a release paper. And a method of bonding a paste layer formed so as to be substantially free of water by drying to a support.

  The range to which the external sheet of the present invention is applied is not limited, and any type of pharmaceuticals, cosmetics, etc. may be used.

  As described above, the external sheet according to the present invention has a form in which the plaster layer is provided on at least one side of the support. Hard to give. Further, it is not necessary to perform complicated operations such as wiping and cleaning. In addition, after being applied to the affected area, it does not adhere to and contaminate clothes or bedding, and the active ingredient is not wiped away by clothes or bedding.

  Moreover, the base of the plaster layer contains an acrylic polymer obtained by polymerizing at least one monomer selected from acrylic acid, acrylic ester, methacrylic acid and methacrylic ester, and polyvinyl alcohol. Therefore, a necessary amount of urea or urea and glycerin can be contained, whereby a sufficient moisturizing effect can be obtained, and rough skin such as cracks and scratches can be effectively treated.

  In the present invention, when a filler for improving the cohesive force is blended, the cohesive force of the paste layer is further increased, and thereby a sufficient amount of urea or urea and glycerin is contained in the paste layer. It is possible to further enhance the effect of rough skin treatment.

  In the present invention, when the plaster layer contains substantially no moisture, it is possible to effectively suppress the occurrence of cracks and the like of the stratum corneum due to drying of the skin stratum corneum after use, and even more effective rough skin. Can be improved.

  Hereinafter, the present invention will be described in more detail by describing specific examples of the present invention.

(raw materials)
In the following examples and comparative examples, the following raw materials were used.

  1) Urea (manufactured by Kominato Pharmaceutical)

  2) Glycerin (concentrated glycerin, Sakamoto Pharmaceutical Co., Ltd.)

  3) Adhesive

  The following two types of adhesives were prepared.

Adhesive 1… Nippon Carbide Kogyo Co., Ltd., trade name “Nicazole TS-620” (methyl acrylate-acrylic acid-2-ethylhexyl copolymer resin emulsion adhesive)
Adhesive 2 ... made by Nippon Acrylic Co., Ltd., trade name "Primal N-580NF" (acrylic emulsion adhesive mainly composed of methacrylic acid-n-butyl acrylate copolymer)

4) Polyvinyl alcohol The following 6 types of polyvinyl alcohol were prepared.

Polyvinyl alcohol A: manufactured by Nihon Vineyard-Poval, product number: JP-15 (polymerization degree: about 1500, saponification degree: 86.0-90.0)
Polyvinyl alcohol B ... Nippon Acetate, manufactured by Poval, product number: JP-18 (degree of polymerization: about 1800, degree of saponification of 87.0-89.0)
Polyvinyl alcohol C ... Nippon Vinegar-Poval, product number: JF-17 (degree of polymerization: about 1700, degree of saponification 98.0 to 99.0)
Polyvinyl alcohol D ... Nippon Vinegar-Poval, product number: JP-33 (degree of polymerization: about 3300, degree of saponification of 86.5-89.5)
Polyvinyl alcohol E ... Nippon Vinegar-Poval, product number: JP-05 (degree of polymerization: about 500, degree of saponification of 87.0-89.0)
Polyvinyl alcohol F ... Nippon Vinegar-Poval, product number: JL-25E (polymerization degree: about 2500, saponification degree 78.0-80.5)

  5) Zinc oxide (Wako Pure Chemical Industries)

  6) Titanium oxide (Wako Pure Chemical Industries)

7) Support Laminate film of polyethylene terephthalate and ethylene-vinyl acetate copolymer

  8) Release material: Release PET film (polyethylene terephthalate film subjected to release treatment with silicone release agent)

(Example 1)
17.7 parts by weight of urea, 20 parts by weight of glycerin, 1 part by weight of polyvinyl alcohol A, and 0.3% of zinc oxide based on 77.7 parts by weight of the acrylic emulsion type pressure-sensitive adhesive “Nicazole TS-620” Part by weight was added and stirred uniformly to prepare a plaster composition. Next, the plaster composition was applied to the surface of the release PET film that had been subjected to the mold release treatment so that the thickness after drying was 70 μm, and dried at 90 ° C. for 10 minutes to form a paste layer. . Thereafter, the plaster layer was laminated on one side of the release agent to obtain an external sheet.

(Examples 2 to 20, 22, and 23)
An external sheet was obtained in the same manner as in Example 1 except that the composition of the plaster composition was as shown in Tables 1 and 2.

(Example 21)
An external sheet was prepared in the same manner as in Example 1 except that the composition of the plaster composition was as shown in Table 2.

(Comparative Example 1)
A commercially available cream preparation (urea ointment) containing 10% by weight of urea having the effect of preventing rough limbs and the like was prepared.

(Comparative Example 2)
A commercially available gel patch containing a moisturizing / drying preventing agent and a skin protecting agent, which is indicated to smooth the skin such as the heel, was prepared.

(Comparative Example 3)
A dispersion obtained by adding 1 part by weight of urea, 9 parts by weight of sodium polyacrylate, and 9 parts by weight of aluminum silicate to 20 parts by weight of glycerin, and gelatin 9 in 50 parts by weight of water. A plaster composition was prepared by adding 2 parts by weight of polyvinyl alcohol and 2 parts by weight of polyvinyl alcohol and mixing with an aqueous solution that was uniformly dissolved while heating. Next, after applying the plaster composition to a thickness of about 1 mm on the surface where the release agent of the release agent was subjected to the treatment, the plaster composition was laminated on one side of the nonwoven fabric, and the film was laminated at 40 ° C. for 2 days. After aging, a gel patch for treating rough skin was obtained.

(Comparative Examples 4 to 8)
An external sheet was obtained in the same manner as in Example 1 except that the formulation of the plaster composition was changed as shown in Table 3.

(Evaluation of Examples and Comparative Examples)
For the external use sheets obtained in Examples 1 to 23, the gel patches of Comparative Examples 2 and 3, and the external use sheets of Comparative Examples 4 to 8 and the commercially available cream preparation of Comparative Example 1, trial tests were conducted by the following methods. Then, the rough skin prevention effect or rough skin treatment effect and the remaining plaster were evaluated. The results are shown in Tables 4-6 below. In addition, the evaluation result of Tables 4-6 set the case where five monitors were set to evaluation 3 to 100, and showed it as a ratio with respect to 100.

  Trial test: For five gel monitors and an external sheet, 5 cm × 5 cm of the gel patch and the external sheet were applied to the knee, heel, or sole of the foot before going to bed. As for the cream, a large amount of the tip of the thumb was applied to the knees, heels or soles before going to bed. After one night, the gel patch and the external sheet were peeled 5 minutes later, the cream was left as it was, and the degree of the rough skin prevention effect or rough skin treatment effect was evaluated according to the following criteria. I was asked to. In addition, the same evaluation was performed 5 hours after the above evaluation.

[Criteria for preventing rough skin or treating rough skin]
Score 3: It was significantly moist before application or application.

  Score 2 ... Moist before application or application.

  Score 1 ... No change before application or application.

  Score 0: Roughness before application or application.

  Furthermore, with regard to the gel patch and the external sheet, five monitors evaluated the remaining level of the plaster layer on the skin immediately after peeling, that is, the degree of adhesive residue, based on the following criteria.

[Criteria for remaining plaster]
Score 3 ... No remaining plaster was observed.

  Score 2 ... No plaster residue was found, but the skin was sticky.

  Score 1 ... The plaster residue was partially recognized.

  Score 0: The plaster remained almost on the entire surface.

  Moreover, the water content in each preparation was measured in the following manner.

Method for measuring water content in preparation: The gel patch and the external sheet were accurately cut into an area of about 10 to 20 cm ² , and the release paper was peeled off, and then the preparation weight A (g) was measured. Next, the paste layer was faced up and dried at room temperature for about 24 hours in a desiccator containing silica gel to obtain the formulation weight B (g). The formulation water content was determined from the formulation weight A and the formulation weight B by the following formula.

Formulation water content (g / m ² ) = (A−B) / formulation area (m ² )

Claims (5)

An external sheet provided with a paste layer containing urea in a base on at least one side of a support,
The base is composed of a polymer obtained by polymerizing at least one monomer selected from acrylic acid, acrylic acid ester, methacrylic acid and methacrylic acid ester, and polyvinyl alcohol. Sheet.   The external sheet according to claim 1, wherein the base further comprises glycerin.   The external sheet according to claim 1 or 2, wherein the base further comprises a filler for improving cohesive force.   The external sheet according to any one of claims 1 to 3, wherein the paste layer substantially does not contain water. The external sheet according to any one of claims 1 to 4, which is intended to improve rough skin.