Graphene-containing nail coating agent

Abstract

To provide a nail coating agent that contains graphene while maintaining adhesion between natural nails and nail decoration materials. [Solution] A nail coating agent comprising graphene and a solvent. A nail coating agent comprising graphene, a solvent and an antibacterial agent, wherein the solvent comprises one or more lower alcohols selected from ethanol, propanol and isopropanol and water.

Description

Technical Field

[0001] The present invention relates to a nail coating agent containing graphene.

Background Art

[0002] In nails where a coloring agent is applied to the nails of hands and feet for decoration, a coating agent is used between the nail and the coloring agent to enhance the adhesion to the coloring agent and improve the durability of the nails. For example, in the case of gel nails using a color gel as the coloring agent, it is common to apply a primer for leveling the irregularities of the natural nail and enhancing the adhesion to the gel and a base gel as the base of the gel, and then apply the color gel. In particular, the primer is used for the purpose of enhancing the adhesion between the natural nail and the gel. In addition, nails are easily damaged by various movements in daily life, such as the accumulation of small loads caused by drying due to wet work, or chemicals such as remover and acetone remover used when removing nails, and troubles such as split nails, cracks, chips, and peeling are known.

[0003] Generally, a primer is applied to correct the irregularities on the nail surface, enhance the adhesion to the gel, prevent the gel from lifting from the natural nail, and improve the durability of the gel. Patent Document 1 describes a nail base coat that can suppress the lifting of the gel nail from the nail surface. However, no primer that can also deal with nail troubles such as peeling has been known.

[0004] Graphene is a sheet-like material with a thickness of one atom, in which carbon atoms are arranged in a hexagonal lattice. Patent document 2 describes the use of graphene nanomaterials in cosmetics to improve the appearance of the skin, particularly to reduce fat in the skin and subcutaneous tissue. Patent document 3 describes a gel nail sticker in which antibacterial / antifungal properties and breathability are improved by incorporating graphene. However, no nail coating agent is known that uses graphene as a primer to address nail problems such as peeling. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2024-109067 [Patent Document 2] Japanese Patent Publication No. 2021-532046 [Patent Document 3] Japanese Patent Publication No. 2023-29176 [Overview of the project] [Problems that the invention aims to solve]

[0006] The present invention relates to a nail coating agent containing graphene that maintains adhesion between the natural nail and the nail decoration material, and to a method for using the same. [Means for solving the problem]

[0007] As a result of diligent research to solve the above problems, the inventors of the present invention have found that a nail coating agent containing graphene and a solvent adheres to nail decoration materials such as gel nails and natural nails, enhances the moisturizing properties of natural nails, improves nail separation and splitting, makes nails less prone to breakage, and contributes to strengthening nails by repairing brittle and broken nails and improving nail color. Based on these findings, the present invention has been completed. In other words, the present invention provides a nail coating agent having the following features. [1] A nail coating agent containing graphene and a solvent. [2] The nail coating agent according to [1], wherein the solvent comprises one or more lower alcohols selected from ethanol, propanol, and isopropanol, and water. [3] A nail coating agent according to either [1] or [2], further comprising an antibacterial agent. [4] A nail coating agent according to any one of [1] to [3], comprising 0.1 ppm to 30 ppm of graphene based on the total mass of the coating agent. [5] A nail coating agent comprising graphene, a solvent, and an antibacterial agent, wherein the solvent comprises one or more lower alcohols selected from ethanol, propanol, and isopropanol, and water. [6] The nail coating agent according to [5], comprising 0.1 ppm to 30 ppm of graphene based on the total mass of the coating agent. [7] A method for applying the nail coating agent described in [1] to [6] above, comprising applying it between a natural nail and an artificial nail composition. [8] A method for applying the nail coating agent described in [1] to [6] above, comprising applying it to the surface between the nail plate and / or the nail tip and the subungual layer. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a nail coating agent that contains graphene while maintaining adhesion between the natural nail and the nail decoration material. Furthermore, according to the present invention, it is possible to improve nail separation and splitting, make nails less prone to breaking, and strengthen nails by repairing brittle and cracked nails and improving nail color. [Brief explanation of the drawing]

[0009] [Figure 1] Cross-section of a nail and names of its parts [Figure 2] This image shows the condition of the nail 24 days after applying Example 4. [Figure 3] This image shows the condition of the nail 79 days after applying Example 4. [Figure 4]These images show the condition of the nails 5 weeks and 10 weeks after applying Example 4. [Modes for carrying out the invention]

[0010] The present invention will be described in more detail below. The coating agent of the present invention is used by applying it to the nails and contains graphene as an active ingredient. Graphene is a sheet-like material with a thickness of one atom, in which carbon atoms are arranged in a hexagonal lattice. In the present invention, graphene may be in flake form or powder form. In the present invention, the flake size (length of one side of graphene) may be about 1 nm to about 1000 nm, about 50 to about 750 nm, about 100 to about 500 nm, or about 100 to about 400 nm. In the present invention, the thickness of the layered structure of graphene may be about 0.1 nm or more, about 0.5 nm or more, about 1 nm or more, about 3 nm or more, or about 5 nm or more, and may be about 30 nm or less, about 15 nm or less, about 10 nm or less, or about 7 nm or less. In the present invention, graphene may be a single layer or a multilayer formed by stacking single-layer graphenes. In the present invention, graphene may also be graphene oxide. Graphene oxide refers to graphene modified with oxygen-containing groups such as carboxyl groups, carbonyl groups, hydroxyl groups, and / or epoxy groups. In the present invention, "graphene" may include reduced graphene oxide. Reduced graphene oxide is generally produced by reducing graphene oxide.

[0011] The coating agent of the present invention may contain about 0.1 ppm to about 30 ppm of graphene, preferably about 0.5 ppm to about 10 ppm, more preferably about 0.7 ppm to about 5 ppm, and even more preferably about 1 ppm to about 3 ppm, based on the total mass of the coating agent. By adjusting the graphene content, it is possible to prevent graphene aggregation, ensure good dispersion within the coating agent, and prevent the coating agent from leaving black particles on the natural nail when applied, thus not affecting the color of the nail decoration material. Furthermore, by changing the pH of the coating agent, it is possible to improve the adhesion of the nail decoration material while maintaining good graphene dispersion and suppressing its impact on the color of the nail decoration material.

[0012] The solvent of the present invention may be water such as purified water or alkaline purified water (alkaline ionized water, alkaline electrolyzed water), lower alcohols such as ethanol, propanol, isopropanol, and butanol, ethyl acetate, aqueous ammonia, or mixtures thereof. The solvent of the present invention may be a mixture of water and lower alcohols. Preferably, the solvent of the present invention may be a mixture of water and ethanol, propanol, and isopropanol. When the solvent is a mixture of water and lower alcohols, the applied nail coating agent dries quickly and exhibits fast-drying properties.

[0013] In the present invention, the mass ratio of water to the total mass of the coating agent may be 0% by mass, may be greater than 0% by mass, preferably about 0.1% by mass or more, more preferably about 0.5% by mass or more, and even more preferably about 1% by mass or more. In the present invention, the mass ratio of lower alcohol to the total mass of the coating agent may be 100% by mass or less, preferably about 99.9% by mass or less, more preferably about 99.5% by mass or less, and even more preferably about 99% by mass or less. By setting the mass ratio of water as described above, the dispersibility of graphene in the coating agent is improved, and it becomes possible to control the adhesion between the natural nail and the nail decoration material, which is preferable. In the present invention, the mixing ratio of water to lower alcohol may be about 0.1:9.9, about 0.5:9.5, about 1:9, about 2:8, or about 3:7. In the present invention, the mixing ratio of water to lower alcohol is preferably about 0.5:9.5, and more preferably about 1:9. By setting the mixing ratio of water and lower alcohol as described above, a coating agent having quick drying properties and in which graphene is well dispersed can be obtained.

[0014] The coating agent of the present invention may have an alkaline pH. The coating agent of the present invention may have a pH of about 8 to 14, preferably a pH of about 8 to about 13, more preferably a pH of about 8 to about 12, and even more preferably a pH of about 8 to about 10. The pH of the coating agent of the present invention refers to the pH at 25°C, and specifically means the value measured using a glass electrode type pH meter. It is known that making the coating agent alkaline can enhance the adhesion between the natural nail and the nail decoration material. On the other hand, it has been found that when the coating agent tends to be alkaline, graphene tends to aggregate and the dispersibility deteriorates. Therefore, it is preferable to adjust the pH of the coating agent of the present invention within a range that adheres the natural nail and the nail decoration material and has good dispersibility of graphene.

[0015] The coating agent of the present invention may contain an antibacterial agent. The antibacterial agent may be any antibacterial agent commonly used in the technical field of this case. The coating agent of the present invention may contain titanium carbide. The titanium carbide may be titanium carbide ceramics obtained by combustion synthesis of titanium and carbon. The titanium carbide may be a ceramic-based porous material obtained by combustion synthesis of titanium, carbon, and silver. The coating agent of the present invention may contain titanium carbide as an antibacterial agent. The coating agent of the present invention may contain titanium oxide / titanium carbide / silver as an antibacterial agent. The coating agent of the present invention may contain titanium carbide (silver / titanium) as an antibacterial agent. The coating agent of the present invention may contain an antibacterial agent in any amount within the range where its effect occurs. The coating agent of the present invention may contain the antibacterial agent at about 1 ppm or more, preferably about 10 ppm or more, more preferably about 50 ppm or more, and still more preferably about 100 ppm or more, based on the total mass of the coating agent. The coating agent of the present invention may contain the antibacterial agent at about 500 ppm or less, preferably about 200 ppm or less, more preferably about 150 ppm or less, and still more preferably about 100 ppm or less, based on the total mass of the coating agent. The coating agent of the present invention preferably contains the antibacterial agent at about 50 ppm to about 150 ppm, based on the total mass of the coating agent. When the antibacterial agent is titanium carbide, it is preferable to adjust the content of the particulate component contained in the coating agent so as to prevent its aggregation while expressing the antibacterial effect of titanium carbide and to disperse it well in the coating agent.

[0016] The coating agent of the present invention can be prepared by adding graphene to a solvent, optionally adding an antibacterial agent, and stirring. Alternatively, graphene and optionally an antibacterial agent may be added to a part of the solvent, and then the remaining solvent may be added for preparation.

[0017] The coating agent of the present invention is applied between the natural nail and the artificial nail composition. The method of applying the coating agent of the present invention between the natural nail and the artificial nail composition may be performed by any method, and may be performed by coating. The artificial nail composition refers to a composition used as a nail decoration material. The artificial nail composition is a composition that is applied to the natural nail or placed on the natural nail to form a film, layer, or structure, etc., to decorate the natural nail or to form an artificial nail on the natural nail. The artificial nail composition may be a curable artificial nail composition. The curable artificial nail composition may be a curable gel-like nail coating material (gel nail). The artificial nail composition may be a gel nail, a sculpture, a polish, or a nail tip. The artificial nail composition may be in any shape, and may be liquid, gel-like, sheet-like, or seal-like.

[0018] The coating agent of the present invention is applied to the surface between the nail plate and / or the tip of the nail (nail tip) and the subungual layer. The nail plate is the hard part commonly called the "nail," and refers to the part of the nail that rests on the nail bed. The nail bed refers to a part of the subcutaneous tissue located beneath the nail (nail plate). The nail tip refers to the white tip of the nail that protrudes from the nail bed as the nail plate grows. The subungual layer is the skin on the underside of the nail, which adheres the nail to the end of the fingertip. When applying the coating agent of the present invention to the surface between the toenail and the subcutaneous tissue, the coating agent of the present invention may also be applied between the natural nail and the artificial nail composition, or it may not be applied between the natural nail and the artificial nail composition. The coating agent of the present invention may be applied by any method, including by coating. A brush may be used when applying the coating agent of the present invention.

[0019] The coating agent of the present invention may be applied to the surface between the nail plate and / or the nail tip and the subungual layer once, twice, three, or four times a month. The coating agent of the present invention may be applied to the surface between the nail plate and / or the nail tip and the subungual layer once, two, three, four, five, six, or seven times a week. The coating agent of the present invention may be applied to the surface between the nail plate and / or the nail tip and the subungual layer once, two, or three times a day. Particularly from the viewpoint of strengthening the nail, it is preferable to apply the coating agent of the present invention to the surface between the nail plate and / or the nail tip and the subungual layer at least once a day.

[0020] In this specification, "detachment" refers to the separation and lifting of the tip of the nail from the nail bed (a portion of the subcutaneous tissue that adheres to the nail plate; the part that appears pink to the outside of the nail). When detachment occurs, the detached area typically appears white or yellow. In this specification, "lift" refers to a state in which an artificial nail composition, such as gel nail, lifts away from the natural nail, creating a gap between the natural nail and the artificial nail composition.

[0021] Study 1: Differences in graphene concentration and their effects Samples containing 10 ppm, 30 ppm, 80 ppm, and 100 ppm of graphene were prepared using alcohol and water as solvents. Eight skilled nail technicians served as panelists. They applied the samples to the entire nail, including the nail plate, instead of a conventional primer, and then performed a standard procedure of applying base gel, color gel, and top gel on top. The effects of different graphene concentrations were observed and examined from the following perspectives: (1) changes in nail condition, (2) presence or absence of lifting, (3) color, and (4) other factors. As a result, when a sample containing graphene was applied, improvements were observed in split nails, gel did not repel when applied on top, and nail polish removal was easier, especially for damaged nails. (1) Regarding the improvement of nail condition, little effect was observed due to differences in graphene concentration. Rather, (2) regarding the presence or absence of lifting and (3) regarding color, differences were observed particularly with a graphene concentration of 100 ppm, such as a tendency to lift, lifting sometimes occurring about a week after treatment, and the presence of black particles. The black particles were thought to be aggregated graphene. On the other hand, little difference was observed in the presence or absence of lifting and color with graphene concentrations of 10 ppm and 30 ppm.

[0022] Study 2: pH of the solvent and the dispersibility of graphene particles Using alcohol and water as solvents, we prepared alcohol / graphene / titanium carbide / water samples and compared the effects of changing the pH of the solvent on the dispersibility of graphene and titanium carbide particles. All of the examples contained 10 ppm graphene and 100 ppm titanium carbide. The alcohols used were mixtures of ethanol, propanol, and isopropanol. The pH was adjusted using a mixture of alkaline purified water and purified water. The results are shown in Table 1. [Measuring pH] 50 ml of each sample was taken, thoroughly mixed, and then measured at 25°C using a pH meter (Horiba LAQUAact portable pH meter). [Table 1]

[0023] Consideration 3: Improvement of nail separation In an alcohol / graphene / titanium carbide / water system, two samples were prepared: one containing 1 ppm of graphene at pH 11.8 (Example 3), and another containing 1 ppm of graphene at pH 8.35 (Example 4). Graphene aggregation was observed in Example 3, but the dispersibility of graphene was good in Example 4. [Table 2] Seven skilled nail technicians served as panelists. They applied the sample from Example 4 to the entire nail, including the nail plate, instead of a conventional primer. They then performed the standard procedure of applying base gel, color gel, and top gel on top of the sample and observed the results from the following perspectives: (1) changes in the condition of the nail, (2) presence or absence of lifting (durability), (3) color, and (4) other factors. (1) To observe the effect, two panelists applied the sample to the entire nail, including the nail plate, during a normal procedure, and then applied the sample once a day after the procedure, from the tip of the nail to the subcutaneous tissue and from the underside of the nail to the detached area. The results are shown in Figures 2 to 4. An improvement in detachment was observed approximately 3 weeks after the start of application. (2) Regarding the presence or absence of lifting (gel nail retention), it was about the same as with conventional primers, and no particular problems were observed. (3) Regarding the color, there were no particular problems, such as the black graphene particles appearing on the nail as observed in Study 1. Regarding the feel of the sample in this example, it was noted that it was smooth and pleasant to use, and that the effect could be felt with use once a day.

[0024] From the above, it has been found that the coating agent of the present invention enhances the adhesion between the nail and the nail decoration material, improves nail separation and splitting, makes nails less prone to breaking, and contributes to strengthening nails by repairing brittle and cracked nails and improving nail color.

Claims

1. A nail coating agent containing graphene and a solvent.

2. The nail coating agent according to claim 1, wherein the solvent comprises one or more lower alcohols selected from ethanol, propanol, and isopropanol, and water.

3. Furthermore, the nail coating agent according to claim 1 or 2, further comprising an antibacterial agent.

4. The nail coating agent according to claim 1 or 2, comprising 0.1 ppm to 30 ppm of graphene based on the total mass of the coating agent.

5. A nail coating agent comprising graphene, a solvent, and an antibacterial agent, wherein the solvent comprises one or more lower alcohols selected from ethanol, propanol, and isopropanol, and water.

6. The nail coating agent according to claim 5, comprising 0.1 ppm to 30 ppm of graphene based on the total mass of the coating agent.

7. A method for applying the nail coating agent described in claim 1 or 5, comprising applying it between a natural nail and an artificial nail composition.

8. A method for applying the nail coating agent described in claim 1 or 5, comprising applying it to the surface between the nail plate and / or the nail tip and the subungual layer.

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