Hardened artificial claw components

Abstract

To provide a curable artificial nail composition that is hard to be affected by curing inhibition by oxygen, suppresses generation of an uncured component on a cured coating surface, has excellent non-wiping property, and in which cured coating has sufficient hardness and flexibility.SOLUTION: A curable artificial nail composition contains (A) a radical-polymerizable urethane oligomer having a mass average molecular weight of 500 or more and less than 5,000, (B) a radical-polymerizable urethane oligomer having a mass average molecular weight of 5,000 or more and 100,000 or less, (C) a radical-polymerizable monomer having hydroxyl group, (D) a polyfunctional thiol compound, and (E) polymerization initiator.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to a curable artificial nail composition. [Background technology]

[0002] Nail art, which involves decorating natural fingernails and toenails, or attaching artificial nails and then decorating them, is becoming increasingly popular. Furthermore, artificial nails are being formed on top of natural nails to reinforce them and prevent breakage or peeling due to external forces. For the purpose of decorating and strengthening nails, resin-based materials, commonly known as manicures, pedicures, or sculptures, are applied to the nails.

[0003] Recently, gel nails, which are curable artificial nail compositions, have been attracting attention as materials used for nail decoration or reinforcement. Gel nails are curable gel-like nail coating materials (curable artificial nail compositions), and are known to contain, for example, (meth)acrylate oligomers and (meth)acrylic monomers. Gel nails are applied to the nails and harden through a radical polymerization reaction by exposure to ultraviolet light, forming a cross-linked polymer film, which is said to create a tough film that is difficult to peel off the nails.

[0004] Examples of curable artificial nail compositions such as gel nails include the following: Patent Document 1 describes a photocurable artificial nail composition containing a urethane (meth)acrylate oligomer, a (meth)acrylic monomer, a polyfunctional thiol, and a photopolymerization initiator, wherein the average acrylic equivalent of the entire urethane (meth)acrylate oligomer is 400 to 2000 and the weight-average molecular weight of the urethane (meth)acrylate oligomer is 3000 or more. This photocurable artificial nail composition is said to have sufficient strength even when cured by ultraviolet light, has low skin irritation, and does not contain uncured monomers after curing, thus allowing for rapid film formation and a glossy film surface. Patent Document 2 describes an artificial nail raw material composition comprising (A) a radical polymerizable compound having one or more radical polymerizable unsaturated bonds in one molecule, (B) a polyfunctional thiol compound having two or more thiol groups in one molecule, and (C) a photopolymerization initiator. This artificial nail raw material composition is said to be able to maintain adhesion between the artificial nail and the natural nail for a long period of time without the use of adhesives and primers, and to allow the artificial nail to be easily removed from the natural nail. Patent Document 3 describes a photocurable artificial nail composition comprising: (A) a urethane (meth)acrylate oligomer having at least one (meth)acrylate group and at least one urethane bond in one molecule; (B) a polyfunctional thiol compound having two or more thiol groups in one molecule; (C) a radical polymerizable compound having one or more radical polymerizable unsaturated bonds in one molecule, which does not fall under components (A) or (B); (D) a photopolymerization initiator; and (E) a chain transfer agent. This photocurable artificial nail composition is said to have excellent surface gloss, easy and quick handling, good surface hardness after photocuring, good stain resistance, and low curing heat generation. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2017-210475 [Patent Document 2] Japanese Patent Publication No. 2014-5260 [Patent Document 3] Japanese Patent Publication No. 2019-6689 [Overview of the project] [Problems that the invention aims to solve]

[0006] The photocurable artificial nail compositions / artificial nail raw material compositions described in Patent Documents 1-3 contain thiol compounds, which makes them less susceptible to oxygen-induced curing inhibition (oxygen inhibition). However, when a cured coating is formed, uncured components are generated on the surface of the cured coating, requiring wiping after application, resulting in poor non-wipeability. Furthermore, the curable artificial nail compositions containing thiol compounds tend to produce hard, brittle, and inflexible cured coatings.

[0007] The problem that the present invention aims to solve is to provide a curable artificial nail composition that is less susceptible to the effects of oxygen-induced curing inhibition, suppresses the generation of uncured components on the surface of the cured coating film, exhibits excellent non-wipeability, has a cured coating film with sufficient hardness and flexibility, and has excellent application workability. [Means for solving the problem]

[0008] The inventors of the present invention conducted diligent research to solve the above problems and found that the above problems can be solved by creating a curable artificial nail composition with a specific composition, thus completing the present invention. Specifically, it is as follows: [Section 1] (A) Radical polymerizable urethane oligomers with a mass-average molecular weight of 500 or more and less than 5,000, (B) Radical polymerizable urethane oligomers having a mass-average molecular weight of 5,000 or more and 100,000 or less. (C) A radical polymerizable monomer having a hydroxyl group, (D) Polyfunctional thiol compounds, and (E) Polymerization initiator, A hardening artificial nail composition containing [the specified ingredient]. [Section 2] The above (A) radical polymerizable urethane oligomer having a mass-average molecular weight of 500 or more and less than 5,000, (A1) Urethane oligomers having a mass-average molecular weight of 500 or more and less than 2,700, and having 3 or more radical polymerizable groups in one molecule, (A2) Urethane oligomers having a mass-average molecular weight of 2,700 or more and less than 5,000, and having two radical polymerizable groups in one molecule. A curable artificial nail composition according to item 1, comprising the above. [Section 3] (F) A curable artificial nail composition according to item 1 or 2, comprising a polymerization inhibitor. [Effects of the Invention]

[0009] The present invention provides a curable artificial nail composition that is less susceptible to curing inhibition by oxygen, suppresses the generation of uncured components on the surface of the cured coating film, exhibits excellent non-wipeability, has a cured coating film with sufficient hardness and flexibility, and offers excellent application workability.

[0010] The inventors of the present invention surmise that because the curable artificial nail composition contains (A) a urethane oligomer, (C) a radical polymerizable monomer having a hydroxyl group, and (D) a polyfunctional thiol compound, its reactivity is increased, and as a result, the generation of unreacted radical polymerizable compounds can be suppressed, thus eliminating the need to wipe the surface of the coating after the cured coating is formed (excellent non-wipe properties). The curable artificial nail composition of the present invention is extremely useful in that it has discovered a novel composition that achieves non-wipe properties. Furthermore, it is useful not only for its non-wipe properties, but also because the cured coating does not become too hard and brittle, but rather has appropriate flexibility. Non-wipe properties and flexibility of the cured coating are conflicting characteristics. If non-wipe properties are prioritized, the reactivity needs to be increased, which may cause the cured coating to become hard and brittle. On the other hand, if flexibility of the cured coating is prioritized, the radical polymerizable groups in the curable artificial nail composition decrease, resulting in a decrease in non-wipe properties.

[0011] It is believed that the urethane oligomer in (A) has the function of increasing the ratio of radical polymerizable groups in the curable artificial nail composition, thereby improving the curability of the curable artificial nail composition, improving the surface curability of the cured coating film, and eliminating the need to wipe the coating film surface after the cured coating film is formed (excellent non-wipe properties).

[0012] (C) The radically polymerizable monomer having a hydroxyl group causes the distance between radically polymerizable groups to shrink due to hydrogen bonding caused by the hydroxyl group, and the radically polymerizable groups are present in a close range to each other in the state before the reaction. Thus, at the start of the reaction, the radically polymerizable groups are likely to meet, which can increase the curability of the curable artificial nail composition, improve the surface curability of the cured coating film, and it is presumed that there is no need to wipe the coating film surface after forming the cured coating film (excellent non-wiping property).

[0013] (D) The polyfunctional thiol compound is considered to function as a chain transfer agent. Since the reaction of the curable artificial nail composition proceeds without being affected by oxygen inhibition, it is presumed that the surface curability of the cured coating film is improved and there is no need to wipe the coating film surface after forming the cured coating film.

[0014] In addition, the inventor of the present invention believes that if the curable artificial nail composition contains only the urethane oligomer of (A), the radically polymerizable monomer having a hydroxyl group of (C), and the polyfunctional thiol compound of (D), the curability of the curable artificial nail composition becomes too high, and the cured coating film tends to become hard and brittle. Therefore, by containing the urethane oligomer of (B), it is presumed that flexibility can be imparted to the cured coating film while maintaining the excellent non-wiping property (no need to wipe the coating film surface after forming the cured coating film). Note that the present invention is not limited to these presumptions.

Embodiments for Carrying Out the Invention

[0015] Hereinafter, the curable artificial nail composition of the present invention will be described in detail. In the specification and claims of the present application, “(meth)acryl” means both acrylic and methacrylic, “(meth)acryloyl” means both acryloyl and methacryloyl, “(meth)acrylate” means both acrylate and methacrylate, and “(meth)acrylamide” means both acrylamide and methacrylamide.

[0016] [(A) Radical polymerizable urethane oligomers with a mass-average molecular weight of 500 or more and less than 5,000] The (A) radical polymerizable urethane oligomer having a mass average molecular weight of 500 or more and less than 5,000 contained in the curable artificial nail composition of the present invention is not particularly limited as long as it is one or more urethane oligomers having one or more radical polymerizable groups in the molecule and a mass average molecular weight of 500 or more and less than 5,000. One or more radical polymerizable urethane oligomers having a mass average molecular weight of 500 or more and less than 5,000 can be used. By incorporating a radically polymerizable urethane oligomer with a mass-average molecular weight of 500 or more and less than 5,000, the curability, curing heat, off-resistance of the cured coating, hardness of the cured coating, and elongation of the cured coating of the curable artificial nail composition can be optimized. In addition, the viscosity of the curable artificial nail composition can be set to an appropriate range for film formation.

[0017] Examples of radical polymerizable groups include vinyl groups, (meth)acryloyl groups, (meth)acrylamide groups, allyl groups, and styryl groups. As the (A) radical polymerizable urethane oligomer having a mass-average molecular weight of 500 or more and less than 5,000 contained in the curable artificial nail composition of the present invention, a urethane (meth)acrylate oligomer in which the radical polymerizable group is a (meth)acryloyl group is preferred.

[0018] The number of radical polymerizable groups, particularly (meth)acryloyl groups, contained within the molecule of a radical polymerizable urethane oligomer with a mass-average molecular weight of 500 or more and less than 5,000 is not particularly limited. From the viewpoint of curability, heat of curing, hardness of the cured coating film, and elongation of the cured coating film of the curable artificial nail composition, there are preferably two or more such groups, for example, 10 or fewer, and preferably 8 or fewer. The radical polymerizable groups may be located at either the molecular ends or side chains of the polyurethane oligomer, and are preferably at the molecular ends. The number of radical polymerizable groups, particularly (meth)acryloyl groups, can be confirmed by analysis using infrared absorption spectroscopy (IR), nuclear magnetic resonance (NMR), gas chromatography-mass spectrometry (GC / MS), etc.

[0019] (A) The mass-average molecular weight of the radical polymerizable urethane oligomer having a mass-average molecular weight of 500 or more and less than 5,000 is preferably 1,000 or more, more preferably 1,500 or more, preferably 4,500 or less, more preferably 4,300 or less, and even more preferably 4,000 or less.

[0020] The curable artificial nail composition of the present invention comprises (A) a radical polymerizable urethane oligomer having a mass average molecular weight of 500 or more and less than 5,000, (A1) a urethane oligomer having a mass average molecular weight of 500 or more and less than 2,700, and having 3 or more radical polymerizable groups in one molecule, and (A2) It is preferable to contain a urethane oligomer having a mass-average molecular weight of 2,700 or more and less than 5,000, and having two radical polymerizable groups in one molecule. As the urethane oligomers of (A1) and (A2), urethane (meth)acrylate oligomers in which the radical polymerizable group is a (meth)acryloyl group are preferred.

[0021] The mass-average molecular weight of the urethane oligomer of (A1) is 500 or more and less than 2,700, preferably 800 or more, more preferably 1,000 or more, preferably 2,600 or less, and more preferably 2,500 or less. The number of radical polymerizable groups, particularly (meth)acryloyl groups, contained within the molecule of the urethane oligomer of (A1) is 3 or more, preferably 4 or more, for example, 10 or less, preferably 8 or less. By incorporating the urethane oligomer of (A1), the curability, curing heat, off-resistance of the cured coating, hardness of the cured coating, and elongation of the cured coating of the curable artificial nail composition can be optimized. In addition, the viscosity of the curable artificial nail composition can be set to an appropriate range for film formation. In particular, since the number of radical polymerizable groups, especially (meth)acryloyl groups, contained in one molecule is three or more, the curability and hardness of the cured coating of the curable artificial nail composition can be adjusted and controlled.

[0022] The mass-average molecular weight of the urethane oligomer of (A2) is 2,700 or more and less than 5,000, preferably 2,800 or more, preferably 4,500 or less, and more preferably 4,300 or less. By incorporating the urethane oligomer of (A2), the curability, curing heat, off-resistance of the cured coating, hardness of the cured coating, and elongation of the cured coating of the curable artificial nail composition can be optimized. In addition, the viscosity of the curable artificial nail composition can be set to an appropriate range for film formation. In particular, since the number of radical polymerizable groups, especially (meth)acryloyl groups, contained in one molecule is 2, while the mass-average molecular weight is 2,700 or more and less than 5,000, the curing heat, off-resistance and elongation of the cured coating of the curable artificial nail composition can be adjusted and controlled.

[0023] Radical polymerizable urethane oligomers having a mass-average molecular weight of 500 or more and less than 5,000 can be synthesized, for example, by reacting a polyurethane oligomer having hydroxyl groups and / or isocyanate groups obtained by the reaction of a polyol and a polyisocyanate with a radical polymerizable compound having a functional group that reacts with hydroxyl groups and / or a functional group that reacts with isocyanate groups within the molecule, but are not limited to this. Radical polymerizable urethane oligomers having a mass-average molecular weight of 500 or more and less than 5,000 preferably have one or more skeletons selected from the group consisting of, for example, a polyether skeleton, a poly(meth)acrylate skeleton, a polyolefin skeleton, a polyester skeleton, a polyurethane skeleton, a polycarbonate skeleton, etc. It is more preferable that they have one or more of the polyether skeleton, a polycarbonate skeleton, and a polyester skeleton.

[0024] Examples of polyols that can be used in the synthesis of radically polymerizable urethane oligomers having a mass-average molecular weight of 500 or more and less than 5,000 include, but are not limited to, one or more selected from the group consisting of polyether polyols, polycarbonate polyols, polyester polyols, polyacrylate polyols (acrylic polyols), polyurethane polyols, polyolefin polyols, alkylene polyols, etc. Examples of polyisocyanates that can be used in the synthesis of radically polymerizable urethane oligomers having a mass-average molecular weight of 500 or more and less than 5,000 include, but are not limited to, aliphatic polyisocyanates (such as hexamethylene diisocyanate), alicyclic polyisocyanates (such as isobornyl diisocyanate, bis(isocyanatomethyl)cyclohexane, dicyclohexylmethane diisocyanate, norbornane diisocyanate), aromatic polyisocyanates (such as diphenylmethane diisocyanate, toluene diisocyanate, phenylenediisocyanate), aromatic aliphatic polyisocyanates (such as xylylene diisocyanate), and one or more selected from the group consisting of dimers, trimers, biuretes, allophanates, uretodiones, uretoimines, isocyanurates, oxadiazinetriones, crude compounds, etc. of these polyisocyanates. When synthesizing radical polymerizable urethane oligomers with a mass-average molecular weight of 500 or more and less than 5,000, radical polymerizable compounds having a functional group that reacts with a hydroxyl group and / or a functional group that reacts with an isocyanate group can be used. Examples include, but are not limited to, one or more compounds selected from the group consisting of (meth)acrylate group-containing compounds having a group that reacts with an isocyanate group (such as a hydroxyl group, carboxyl group, amino group, mercapto group, etc.) (e.g., hydroxyalkyl (meth)acrylate, acrylic acid, etc.) and (meth)acrylate group-containing compounds having a functional group that reacts with a hydroxyl group (such as an isocyanate group, carboxyl group, etc.) (e.g., isocyanatoalkyl (meth)acrylate, etc.).

[0025] Commercially available radical polymerizable urethane oligomers with a mass-average molecular weight of 500 or more and less than 5,000 may be used. (A1) Commercial urethane oligomers having a mass-average molecular weight of 500 or more and less than 2,700, and possessing three or more radical polymerizable groups in one molecule, include, but are not limited to, one or more selected from the group consisting of KN21-94A, KN21-94B, KN21-95A, etc. (A2) Commercial urethane oligomers having a mass-average molecular weight of 2,700 or more and less than 5,000, and possessing two radical polymerizable groups in one molecule, include, but are not limited to, one or more selected from the group consisting of SUA-16N, SUA-2, KT21-032, etc.

[0026] In the curable artificial nail composition of the present invention, (A) the content of radical polymerizable urethane oligomer having a mass-average molecular weight of 500 or more and less than 5,000 is, for example, 45.0% by mass or more, preferably 50.0% by mass or more, more preferably 55.0% by mass or more, and for example, 95.0% by mass or less, preferably 92.0% by mass or less, and more preferably 90.0% by mass or less, based on 100% by mass of the total amount of components of the curable artificial nail composition. In the curable artificial nail composition of the present invention, when the urethane oligomer of (A) contains the urethane oligomer of (A1) and the urethane oligomer of (A2), the content of the urethane oligomer of (A1) is, for example, 30.0% by mass or more, preferably 33.0% by mass or more, more preferably 36.0% by mass or more, and for example, 55.0% by mass or less, preferably 50.0% by mass or less, and more preferably 45.0% by mass or less, based on the total amount of components of the curable artificial nail composition as 100% by mass. If the content exceeds 55.0% by mass, the cured coating film may become hard and brittle. The content of the urethane oligomer of (A2) is, for example, 15.0% by mass or more, preferably 20.0% by mass or more, more preferably 25.0% by mass or more, and for example, 55.0% by mass or less, preferably 50.0% by mass or less, and more preferably 45.0% by mass or less. If the content exceeds 55.0% by mass, the curability of the curable composition may decrease.

[0027] [(B) Radical polymerizable urethane oligomers with a mass-average molecular weight of 5,000 or more and 100,000 or less] The (B) radical polymerizable urethane oligomer having a mass average molecular weight of 5,000 to 100,000 contained in the curable artificial nail composition of the present invention is not particularly limited as long as it is one or more urethane oligomers having one or more radical polymerizable groups in the molecule and a mass average molecular weight of 5,000 to 100,000. One or more radical polymerizable urethane oligomers having a mass average molecular weight of 5,000 to 100,000 can be used. By incorporating a radical polymerizable urethane oligomer with a mass-average molecular weight of 5,000 to 100,000, the curability, curing heat, off-resistance of the cured coating, hardness of the cured coating, and elongation of the cured coating of the curable artificial nail composition can be optimized. In addition, the viscosity of the curable artificial nail composition can be set to an appropriate range for film formation.

[0028] Examples of radical polymerizable groups include vinyl groups, (meth)acryloyl groups, (meth)acrylamide groups, allyl groups, and styryl groups. As the (B) radical polymerizable urethane oligomer having a mass-average molecular weight of 5,000 to 100,000 contained in the curable artificial nail composition of the present invention, a urethane (meth)acrylate oligomer in which the radical polymerizable group is a (meth)acryloyl group is preferred.

[0029] The number of radical polymerizable groups, particularly (meth)acryloyl groups, contained within the molecule of a radical polymerizable urethane oligomer with a mass-average molecular weight of 5,000 to 100,000 is not particularly limited. From the viewpoint of curability, heat of curing, hardness of the cured coating film, and elongation of the cured coating film of the curable artificial nail composition, there are preferably two or more such groups, for example, six or fewer, and preferably four or fewer. The radical polymerizable groups may be located at the molecular ends or side chains of the polyurethane oligomer, and are preferably at the molecular ends. The number of radical polymerizable groups, particularly (meth)acryloyl groups, can be confirmed by analysis using infrared absorption spectroscopy (IR), nuclear magnetic resonance (NMR), gas chromatography-mass spectrometry (GC / MS), etc.

[0030] The mass-average molecular weight of the radical polymerizable urethane oligomer, which has a mass-average molecular weight of 5,000 to 100,000, is preferably 10,000 or more, more preferably 15,000 or more, preferably 70,000 or less, more preferably 50,000 or less, and even more preferably 30,000 or less.

[0031] Radical polymerizable urethane oligomers having a mass-average molecular weight of 5,000 to 100,000 can be synthesized, for example, by reacting a polyurethane oligomer having hydroxyl groups and / or isocyanate groups obtained by the reaction of a polyol and a polyisocyanate with a radical polymerizable compound having a functional group that reacts with hydroxyl groups and / or a functional group that reacts with isocyanate groups within the molecule, but are not limited to this. Radical polymerizable urethane oligomers having a mass-average molecular weight of 5,000 to 100,000 preferably have one or more skeletons selected from the group consisting of, for example, a polyether skeleton, a poly(meth)acrylate skeleton, a polyolefin skeleton, a polyester skeleton, a polyurethane skeleton, a polycarbonate skeleton, etc. It is more preferable that they have one or more of the polyether skeleton, a polycarbonate skeleton, and a polyester skeleton.

[0032] The "polyols," "polyisocyanates," and "radical polymerizable compounds having a functional group that reacts with a hydroxyl group in the molecule and / or a functional group that reacts with an isocyanate group" that can be used in the synthesis of radical polymerizable urethane oligomers having a mass-average molecular weight of 5,000 or more and 100,000 or less may be the same as the "polyols," "polyisocyanates," and "radical polymerizable compounds having a functional group that reacts with a hydroxyl group in the molecule and / or a functional group that reacts with an isocyanate group" that can be used in the synthesis of "[(A) Radical polymerizable urethane oligomers having a mass-average molecular weight of 500 or more and less than 5,000]" described above.

[0033] As a radical polymerizable urethane oligomer with a mass-average molecular weight of 5,000 to 100,000, commercially available products may be used. Commercially available products include, for example, UA-306H, UA-306T, UA-306I, UA-510H (manufactured by Kyoeisha Chemical Co., Ltd.), RUA-071, RUA-003VE, RUA-075, RUA-048 (manufactured by Asia Chemical Industries Co., Ltd.), UV-7550B, UV-6630B, UV-7000B, UV-2000B, UV-2750B, UV-3000B, UV-3200B, UV-3300B, UV-3310B, UV-3700B, UV-6640B (manufactured by Mitsubishi Chemical Corporation), UN-9000PEP, UN-9200A, AU-2040 (manufactured by Tokushiki Co., Ltd.), KUA-PC2I, SUA TH1, SUA TH2 (manufactured by KSM Co., Ltd.), and Art Resin. One or more types selected from the group consisting of UN-6207, UN-6304, UN-6305, UN-350, UN-7600, UN-7700, UN-9200A, UN-5500 (manufactured by Negami Kogyo Co., Ltd.), etc., are listed, but are not limited to these.

[0034] In the curable artificial nail composition of the present invention, (B) the content of radical polymerizable urethane oligomer having a mass-average molecular weight of 5,000 or more and 100,000 or less is, for example, 1.0% by mass or more, preferably 1.5% by mass or more, more preferably 2.0% by mass or more, and for example, 35.0% by mass or less, preferably 30.0% by mass or less, and more preferably 25.0% by mass or less, based on 100% by mass of the total amount of components of the curable artificial nail composition. If the content exceeds 35.0% by mass, the viscosity of the curable artificial nail composition may increase, reducing the workability for application (making it difficult to apply). If the content is less than 1.0% by mass, the viscosity of the curable artificial nail composition may decrease, reducing the workability for application (making it difficult to apply), and the cured coating film may become hard and brittle.

[0035] [(C) Hydroxyl group-containing radical polymerizable monomer] The hydroxyl group-containing radical polymerizable monomer contained in the curable artificial nail composition of the present invention is not particularly limited, as long as it is a monomer having one or more hydroxyl groups and one or more radical polymerizable groups in its molecule. One or more hydroxyl group-containing radical polymerizable monomers can be used. By incorporating a radical polymerizable monomer having a hydroxyl group, the curability, curing heat, off-resistance of the cured coating, hardness of the cured coating, and elongation of the cured coating of the curable artificial nail composition can be optimized. In addition, the viscosity of the curable artificial nail composition can be set to an appropriate range for film formation. Examples of radical polymerizable groups include vinyl groups, (meth)acryloyl groups, (meth)acrylamide groups, allyl groups, and styryl groups.

[0036] Examples of radical polymerizable monomers having a hydroxyl group include one or more selected from the group consisting of 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, N-methylol (meth)acrylamide, N-(2-hydroxyethyl)(meth)acrylamide, N-(3-hydroxypropyl)(meth)acrylamide, N-(2-hydroxypropyl)(meth)acrylamide, N-(4-hydroxybutyl)(meth)acrylamide, 4-hydroxystyrene, 3-hydroxystyrene, etc. Among these, acrylate monomers having a hydroxyl group are preferred, and one or more selected from the group consisting of 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 2-hydroxybutyl (meth)acrylate are more preferred.

[0037] In the curable artificial nail composition of the present invention, the content of (C) radical polymerizable monomer having a hydroxyl group is, for example, 5.0% by mass or more, preferably 7.5% by mass or more, more preferably 10.0% by mass or more, and for example, 30.0% by mass or less, preferably 25.0% by mass or less, and more preferably 20.0% by mass or less, based on 100% by mass of the total amount of components of the curable artificial nail composition. If the content exceeds 30.0% by mass, the viscosity of the curable artificial nail composition may decrease, reducing its applicability (making it difficult to apply), and the heat generated during curing of the curable artificial nail composition may increase, potentially causing the cured coating film to crack easily. If the content is less than 5.0% by mass, the viscosity of the curable artificial nail composition may increase, reducing its applicability (making it difficult to apply), and the curing time of the curable artificial nail composition may increase, potentially leaving uncured components on the surface of the cured coating film.

[0038] [(D) Polyfunctional thiol compounds] The (D) polyfunctional thiol compound contained in the curable artificial nail composition of the present invention is incorporated as a curability modifier, crosslinking agent, and viscosity modifier of the curable artificial nail composition. Polyfunctional thiol compounds also function as chain transfer agents and form the building blocks of the cured coating film in curable artificial nail compositions. When the radical polymerizable unsaturated double bonds (A) to (C) of the polyfunctional thiol compounds undergo radical polymerization, they receive radicals from the growing polymer chain, stopping polymerization (stopping the elongation of the polymer chain) and simultaneously generating new radicals to initiate the growth reaction of another polymer chain. By incorporating polyfunctional thiol compounds into curable artificial nail compositions, the non-wipeability of the cured coating film can be improved.

[0039] Polyfunctional thiol compounds are not particularly limited as long as they are compounds having two or more thiol groups in their molecule. Examples include those obtained by reacting a hydroxyl group of a polyol compound such as trimethylolpropane, pentaerythritol, or dipentaerythritol with a compound having a thiol group or a group that reacts to form a thiol group. For example, trimethylolpropane tris(3-mercaptopropionate), tris[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, pentaerythritol tetrakis(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptopropionate), dipentaerythritol hexakis(3-mercaptopropionate), trimethylolpropane tristhioglycolate, and pentaerythritol tetrakisthioglycolate. One or more substances selected from the group consisting of glycolate, 1,2-ethanedithiol, 1,3-propanedithiol, 1,4-butanedithiol, 1,6-hexanedithiol, 1,8-octanedithiol, 1,2-cyclohexanedithiol, decanedithiol, ethylene glycol bisthioglycolate, ethylene glycol bisthiopropionate, ethylene glycol bisthioglycolate, 1,4-butanediol bisthiopropionate, etc. Among these, compounds having four or more thiol groups in the molecule are preferred, and one or more selected from the group consisting of pentaerythritol tetrakis(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptopropionate), and dipentaerythritol hexakis(3-mercaptopropionate) are more preferred.

[0040] In the curable artificial nail composition of the present invention, the content of (D) polyfunctional thiol compound is, for example, 1.0% by mass or more, preferably 1.5% by mass or more, more preferably 2.0% by mass or more, and for example, 10.0% by mass or less, preferably 7.0% by mass or less, and more preferably 5.0% by mass or less, based on 100% by mass of the total amount of components of the curable artificial nail composition.

[0041] [(E) Polymerization initiator] The polymerization initiator (E) contained in the curable artificial nail composition of the present invention is not particularly limited, as long as it can generate radicals and initiate polymerization of the curable artificial nail composition when energy is applied by light (e.g., ultraviolet light) or heat irradiation.

[0042] Examples of polymerization initiators include one or more polymerization initiators selected from the group consisting of acylphosphine oxides, α-hydroxyalkylphenones, benzoin ethers, benzyl ketals, acid esters, α-aminoalkylphenones, benzophenones, thioxanthones, titanocenes, quinones, peroxides, azos, persulfates, and the like.

[0043] Of these, using a photopolymerization initiator allows for good curability of the curable artificial nail composition even when irradiated with light from various light sources, including UV-LED light sources. For example, acylphosphine oxide polymerization initiators generate radicals when irradiated with ultraviolet light of wavelengths between 365 and 405 nm emitted from commonly used UV-LED light sources. Therefore, good curability can be imparted to the curable composition even when cured by irradiating with light from various light sources, including UV-LED light sources. Furthermore, when curing by irradiating with light from a UV-LED light source, yellowing of the cured coating can be prevented. Examples of acylphosphine oxide polymerization initiators include one or more selected from the group consisting of 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide. In particular, 2,4,6-trimethylbenzoyldiphenylphosphine oxide can be preferably used in the present invention because it also functions as a skin conditioning agent.

[0044] Examples of polymerization initiators other than acylphosphine oxide-based polymerization initiators include 1-hydroxycyclohexylphenyl ketone (IRGACURE184), 1-(4-(phenylthio)-2,2-(O-benzoyloxime))1-hydroxycyclohexylphenyl ketone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methylpropan-1-one, 2-H Droxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]-phenyl}-2-methylpropan-1-one, 1-[4-(2-hydroxyethoxy)phenyl]-2-hydroxy-2-methyl-1-propan-1-one, thioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 1-chloro-4-propylthioxanthone, 3-[3,4-dimethyl-9-oxo-9H-thioxanthone-2-yl-o [Xyxy]-2-hydroxypropyl-N,N,N-trimethylammonium chloride, fluorothioxanthone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, oligo(2-hydroxy-2-methyl-1-(4-(1-methylvinyl)phenyl)propanone), 4-benzoyl-4'-methyl-diphenyl sulfide, 1,2-octanedione, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino Propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]phenyl}-2-methylpropane, isophthalphenone, methyl phenylglyoxyate, butylanthraquinone, ethylanthraquinone, phenanthrenequinone, camphorquinone, benzophenone, 4-phenylbenzophenone, benzoylbenzoic acid, hydroxybenzophenone, 4,4'-Bis(diethylamino)benzophenone, benzoin, benzoin ethyl ether, benzoin isopropyl ether, benzoin butyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, 4-phenoxydichloroacetophenone, 4-t-butyl-dichloroacetophenone, 4-t-butyl-trichloroacetophenone, diethoxyacetophenone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone, 2,2'-azobis(4-methoxy-2,4-dimethylvaleronitrile), 2,2' -Azobis(2-amidinopropane) dihydrochloride, 2,2'-Azobis(2,4-dimethylvaleronitrile), 2,2'-Azobis(isobutyronitrile), 2,2'-Azobis-2-methylbutyronitrile, 1,1-Azobis(1-cyclohexanecarbonitride), 2,2'-Azobis(2-methylpropionitrile), 2,2'-Azobis(2-cyclopropylpropionitrile), 2,2'-Azobis(methylisobutyrate), t-butyl hydroperoxide, cumene hydroperoxide, diacetyl peroxide, didecanoyl peroxide Di-t-butyl peroxide, methyl ethyl ketone peroxide, cyclohexanone peroxide, dicumyl peroxide, di(3,5,5-trimethylhexanoyl) peroxide, 2,5-dimethylhexane-2,5-dihydroperoxide, dilauroyl peroxide, disaxinic acid peroxide, dibenzoyl peroxide, parachlorobenzoyl peroxide, 2,4-dichlorobenzoyl peroxide, t-butyl peroxypivalate, t-butyl peroxybenzoate, t-hexyl peroxide Side valerate, 2,5-dimethyl-2,5-di(2-ethylhexanoylperoxy)hexane, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate, t-hexylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, n-butyl-4,4-di(t-butylperoxy)valerate, 1,1-di(t-butylperoxy)cyclohexane, 1,1-di(t-hexylperoxy)cyclohexane, 2,2-bis(4,4-di-t-butylperoxycyclohexyl)propane, 1,One or more substances selected from the group consisting of 1-bis(t-butylperoxy)-3,3,5-trimethylcyclohexane, 2,2-bis(t-butylperoxy)butane, 2,2-bis(t-butylperoxy)octane, dicetyl peroxydicarbonate, t-hexylperoxyisopropyl monocarbonate, diisopropyl peroxydicarbonate, t-butylperoxyisopropyl carbonate, di(4-t-butylcyclohexyl)peroxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, potassium persulfate, sodium persulfate, ammonium persulfate, etc.

[0045] In the curable artificial nail composition of the present invention, the content of (E) polymerization initiator is, for example, 0.05% by mass or more, preferably 0.1% by mass or more, more preferably 1.0% by mass or more, and even more preferably 4.0% by mass or more, with the total amount of components of the curable artificial nail composition as 100% by mass, for example, 20.0% by mass or less, preferably 18.0% by mass or less, more preferably 16.0% by mass or less, and even more preferably 15.0% by mass or less. If the content exceeds 20.0% by mass, the molecular weight of the cured coating film may decrease and the cured coating film may become brittle, and the cured coating film of the curable artificial nail composition may yellow (discolor). If the content is less than 0.05% by mass, the curing of the curable artificial nail composition may take a long time, and curing may be incomplete.

[0046] In the curable artificial nail composition of the present invention, it is preferable to use a polymerization initiator containing an acylphosphine oxide polymerization initiator. On the other hand, if the content of the acylphosphine oxide polymerization initiator is high, the cured coating film of the curable artificial nail composition may yellow (discolor), and on the other hand, if the content of the acylphosphine oxide polymerization initiator is low, the curing heat during the formation of the cured coating film of the curable artificial nail composition may be high. For this reason, it is preferable to use an acylphosphine oxide polymerization initiator in combination with other polymerization initiators, and it is preferable to use a polymerization initiator containing an acylphosphine oxide polymerization initiator (e.g., 2,4,6-trimethylbenzoyldiphenylphosphine oxide) and an α-hydroxyalkylphenone polymerization initiator (e.g., 1-hydroxycyclohexylphenyl-ketone).

[0047] In the curable artificial nail composition of the present invention, when a polymerization initiator containing an acylphosphine oxide polymerization initiator and an α-hydroxyalkylphenone polymerization initiator is used, it is preferable that the α-hydroxyalkylphenone polymerization initiator is included in a ratio of 0.8 parts by mass to 4.0 parts by mass per 1 part by mass of the acylphosphine oxide polymerization initiator.

[0048] [(F) Polymerization inhibitors] The curable artificial nail composition of the present invention may also contain (F) a polymerization inhibitor in addition to (A) to (E) above. The polymerization inhibitor is not particularly limited as long as it is a compound that has the effect of suppressing the polymerization reaction (curing reaction) by the (C) polymerization initiator in the curable artificial nail composition. Furthermore, it is even more preferable if the compound has the effect of suppressing the chain transfer of polyfunctional thiol compounds in the curable artificial nail composition.

[0049] Examples of polymerization inhibitors include alkylphenol polymerization inhibitors such as 2,6-di-tert-butylphenol, 2,4-di-tert-butylphenol, 2-tert-butyl-4,6-dimethylphenol, 2,6-di-tert-butyl-4-methylphenol, 2,4,6-tri-tert-butylphenol, dibutylhydroxytoluene, 3,5-bistern-butyl-4-hydroxytoluene, and p-methoxyphenol; and quinone polymerization inhibitors such as hydroquinone, methylhydroquinone, tert-butylhydroquinone, hydroquinone monomethyl ether, benzoquinone, and p-tert-butylcatechol. The following are examples of polymerization inhibitors: amine-based polymerization inhibitors such as diphenylamine, alkylated diphenylamine, N,N'-diphenyl-p-phenylenediamine, and phenothiazine; N-oxyl compounds such as 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl; copper dithiocarbamate-based polymerization inhibitors such as copper dimethyldithiocarbamate, copper diethyldithiocarbamate, and copper dibutyldithiocarbamate; tocopherol-based polymerization inhibitors such as α-tocopherol; salicylic acid-based polymerization inhibitors such as salicylic acid hydrazide; and one or more selected from the group consisting of nitrobenzene, phenothiazine, tetramethylthiuram disulfide, etc. Among these, it is preferable to use one or more selected from the group consisting of α-tocopherol, 2,6-di-tert-butyl-4-methylphenol, 2,4,6-tri-tert-butylphenol, dibutylhydroxytoluene, and 3,5-bisquarlybutyl-4-hydroxytoluene. Furthermore, it is preferable to use a polymerization inhibitor having one hydroxyl group in its molecule, as this further enhances the effect of preventing yellowing of the cured coating film formed after the curable artificial nail composition has hardened following storage.

[0050] In the curable artificial nail composition of the present invention, the content of (F) polymerization inhibitor is, for example, 0% by mass or more and 12.0% by mass or less, based on the total amount of components of the curable artificial nail composition as 100% by mass. Preferably it is 0.8% by mass or more, more preferably 0.9% by mass or more, preferably 11.0% by mass or less, and more preferably 10.5% by mass or less. (B) If a polymerization inhibitor is not included, the storage stability of the curable artificial nail composition may decrease, and the temperature rise during curing may increase (exceeding 23°C). (A) If the polymerization inhibitor content exceeds 12.0% by mass, the cured coating formed after the curable artificial nail composition has been stored may turn yellow.

[0051] [(G) Other ingredients] In addition to (A) to (F) above, various other components may be added to the curable artificial nail composition of the present invention as "(G) other components" within a range that does not adversely affect viscosity, applicability, handling, and durability of the cured coating film. (G) Other components include, for example, one or more additives selected from the group consisting of various additives such as radical polymerizable compounds other than those in (A) to (C) above, colorants, polyol compounds, fragrances, silicone-based or fluorine-based defoaming agents, silane coupling agents such as γ-glycidoxypropyltrimethoxysilane, photopolymerization accelerators such as tertiary amines, chain transfer agents, fillers, surface tension modifiers, flame retardants, antioxidants, ion adsorbents, stress reducers, preservatives, antibacterial agents, flexibility imparters, waxes, halogen trapping agents, leveling agents, wetting improvers, resin particles, and decorative materials.

[0052] <Radical polymerizable compounds other than those mentioned above (A) to (C)> Other radical polymerizable compounds besides those described in (A) to (C) above are not particularly limited. For example, one or more selected from the group consisting of urethane compounds having a radical polymerizable unsaturated double bond with a mass-average molecular weight of less than 500, oligomers other than urethane oligomers having a radical polymerizable unsaturated double bond, and radical polymerizable monomers that do not have a hydroxyl group.

[0053] Other oligomers besides urethane oligomers having radically polymerizable unsaturated double bonds include, for example, one or more selected from the group consisting of epoxy (meth)acrylate oligomers, polyester (meth)acrylate oligomers, polyether (meth)acrylate oligomers, polyolefin (meth)acrylate oligomers, etc. In these oligomers, the number of (meth)acrylate groups contained in the molecule is not particularly limited, but from the viewpoint of curability of the curable artificial nail composition and hardness of the cured coating film, there should be one or more, for example, 10 or less, preferably 8 or less, and more preferably 6 or less. Epoxy (meth)acrylate oligomers can be synthesized, for example, by reacting an epoxy compound having two or more epoxy groups with a (meth)acrylate compound having a functional group that reacts with epoxy groups, but this method is not limited to that. Polyester (meth)acrylate oligomers can be synthesized, for example, by reacting a polyester oligomer having hydroxyl groups and / or carboxyl groups obtained by a reaction between a polyol and a polycarboxylic acid or a ring-opening reaction of a cyclic polyester with a (meth)acrylate compound having a functional group that reacts with hydroxyl groups and / or a functional group that reacts with carboxyl groups in its molecule, but the method is not limited to this.

[0054] Examples of radical polymerizable monomers that do not have a hydroxyl group include one or more selected from the group consisting of (meth)acrylate compounds having one (meth)acrylate group, (meth)acrylate compounds having two or more (meth)acrylate groups, and compounds having radical polymerizable unsaturated groups other than (meth)acrylate groups.

[0055] Examples of (meth)acrylate compounds having one (meth)acrylate group include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, neopentyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, and phenyl (meth)acrylate. Esters of monohydric alcohols such as acrylate, benzyl(meth)acrylate, and adamantyl(meth)acrylate with (meth)acrylic acid; (meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N,N-dipropyl(meth)acrylamide, N,N-diisopropyl(meth)acrylamide, N,N-dibutyl(meth)acrylamide, N,N-diisobutyl(meth)acrylamide, N,N-di-tert- (meth)acrylate group-containing amide compounds such as N,N-diheptyl(meth)acrylamide, N,N-dioctyl(meth)acrylamide, N,N-di-tert-octyl(meth)acrylamide, N,N-didodecyl(meth)acrylamide, N,N-dioctadecyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, and N,N-dimethylaminoethyl(meth)acrylamide; N,N-dimethylaminoethyl(meth)acrylate, N,N-diethylaminoethyl(meth)acrylate One or more selected from the group consisting of nitrogen-containing alkyl (meth)acrylates such as Nt-butylaminoethyl (meth)acrylate; N-(meth)acryloyloxyethyl hexahydrophthalimide, pentamethylpiperidyl (meth)acrylate, isocyanurate di(meth)acrylate, isocyanurate tri(meth)acrylate, triazine tri(meth)acrylate, N-(meth)acryloyloxysuccinimide, N-(meth)acryloyloxyphthalimide, (meth)acryloylmorpholine, and other heterocyclic (meth)acrylates.

[0056] Of these (meth)acrylate compounds having one (meth)acrylate group, it is preferable to select one or more from the group consisting of monohydric alcohols such as methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, neopentyl (meth)acrylate, cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, and (meth)acryloylmorpholine, and esters of (meth)acrylic acid.

[0057] Examples of (meth)acrylate compounds having two or more (meth)acrylate groups include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, polypropylene di(meth)acrylate, ethoxylated polypropylene glycol di(meth)acrylate, ethoxylated propylene glycol di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, glycerin di(meth)acrylate, trimethylolpropane di(meth)acrylate, pentaerythritol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, penta Di(meth)acrylate monomers such as erythritol di(meth)acrylate, bisphenol A ethylene oxide-modified di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, propoxylated bisphenol A di(meth)acrylate (isopyridene diphenyl bis(oxyhydroxypropyl methacrylate), etc.); glycerin tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, ditrimethylolpropane tri(meth)acrylate, trimethylolpropane propylene oxide-modified tri(meth)acrylate, trimethylolpropane ethylene oxide-modified tri(meth)acrylate, pentaerythritol tri(meth)acrylate, ε-caprolactone-modified tris(acryloxyethyl) isocyanurate, etc.; tetra(meth)acrylate monomers such as pentaerythritol tetra(meth)acrylate;One or more substances selected from the group consisting of polypentaerythritol (meth)acrylates such as dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tripentaerythritol (meth)acrylate, and tetrapentaerythritol (meth)acrylate; and (meth)acrylate monomers having four or more (meth)acrylate groups such as ethoxylated isocyanuric acid triacrylate and ethoxylated pentaerythritol tetraacrylate; etc.

[0058] It is preferable to use one or more (meth)acrylate compounds selected from the group consisting of ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, polypropylene di(meth)acrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc., among the (meth)acrylate compounds having two or more (meth)acrylate groups.

[0059] As the radical polymerizable monomer that does not have a hydroxyl group, one or more radical polymerizable phosphoric acid compounds having an acrylate group may be used. The radical polymerizable phosphoric acid compound having an acrylate group is not particularly limited as long as it is a radical polymerizable phosphoric acid compound having an acrylate group and a phosphoric acid group (-P(=O)(OH)2 group or -P(=O)(OH)- group) in its molecule. For example, the following formula; CH2=CH-COO-R 11 -P(=O)(OH)2 CH2=CH-COO-R 12 -P(=O)(OH)-R13 -OCO-CH=CH2 (R in the formula 11 , R 12 and R 13 (This represents a divalent organic group.) One or more compounds selected from the group consisting of compounds represented by [formula] can be mentioned.

[0060] Examples of radical polymerizable phosphoric acid compounds having an acrylate group include 2-acryloyloxyethyl phosphate, 2-acryloyloxypropyl phosphate, 2-acryloyloxybutyl phosphate, 2-acryloyloxypentyl phosphate, 2-acryloyloxyhexyl phosphate, acryloyloxyethyl valerate phosphate, acryloyloxypropyl valerate phosphate, acryloyloxybutyl valerate phosphate, acryloyloxypentyl valerate phosphate, acryloyloxyhexyl valerate phosphate, acryloyloxyethyl caproate phosphate, acryloyloxypropyl caproate phosphate, acryloyloxybutyl caproate phosphate, acryloyloxypentyl caproate phosphate, acryloyloxyhexyl caproate phosphate, and acryloyloxyethyl caprylate phosphate. One or more compounds selected from the group consisting of acrylate, acryloyloxypropyl caprylate phosphate, acryloyloxybutyl caprylate phosphate, acryloyloxypentyl caprylate phosphate, acryloyloxyhexyl caprylate phosphate, bis(2-acryloyloxyethyl) phosphate, bis(2-acryloyloxypropyl) phosphate, bis(2-acryloyloxybutyl) phosphate, bis(2-acryloyloxypentyl) phosphate, bis(2-acryloyloxyhexyl) phosphate, acid phosphooxypolyoxyethylene glycol monoacrylate, acid phosphooxypolyoxypropylene glycol monoacrylate, ethylene oxide-modified diacrylate phosphate, propylene oxide-modified diacrylate phosphate, phosphate-modified epoxy acrylate, etc. As a radical polymerizable phosphoric acid compound having an acrylate group, for example, a radical polymerizable phosphoric acid ester compound having an acrylate group can be used.

[0061] Examples of compounds having radically polymerizable unsaturated groups other than (meth)acrylate groups include compounds having radically polymerizable unsaturated groups (functional groups with polymerizable carbon-carbon double bonds) such as vinyl groups, vinyl ether groups, and allyl groups. Examples of such compounds include one or more selected from the group consisting of allyl glycidyl ether, styrene, α-methylstyrene, vinyltoluene, α-chlorostyrene, vinyl acetate, and the like.

[0062] The content of "radical polymerizable compounds other than (A) to (C)" in the curable artificial nail composition of the present invention can be such that it is, for example, 50% by mass or less, preferably 35% by mass or less. Furthermore, the reactivity and curing heat of the curable artificial nail composition can be adjusted by adjusting the type and amount of "radical polymerizable compounds other than (A) to (C)" contained in the curable artificial nail composition. In the present invention, it is preferable to use one or more compounds selected from the group consisting of cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, etc., as the "radical polymerizable compound other than (A) to (C) above".

[0063] <Coloring agent> The coloring agent has the function of imparting a desired color tone and can be incorporated into the curable artificial nail composition in any amount. Examples of coloring agents include one or more selected from the group consisting of pigments, luminescent materials, dyes, colored resin particles, etc. In particular, one or more selected from the group consisting of inorganic pigments, luminescent materials, organic pigments, dyes, and colored resin particles used in nail coating materials, which do not significantly inhibit the curing of the curable artificial nail composition by ultraviolet irradiation (light irradiation).

[0064] Examples of colorants include Brown No. 201, Black No. 401, Purple No. 201, Purple No. 401, Blue No. 1, Blue No. 2, Blue No. 201, Blue No. 202, Blue No. 203, Blue No. 204, Blue No. 205, Blue No. 403, Blue No. 404, Green No. 201, Green No. 202, Green No. 204, Green No. 205, Green No. 3, Green No. 401, Green No. 402, Yellow No. 201, Yellow No. 202-(1), Yellow No. 202-( 2), Yellow No. 203, Yellow No. 204, Yellow No. 205, Yellow No. 4, Yellow No. 401, Yellow No. 402, Yellow No. 403-(1), Yellow No. 404, Yellow No. 405, Yellow No. 406, Orange No. 201, Orange 20 No. 3, Orange No. 204, Orange No. 205, Orange No. 206, Orange No. 207, Orange No. 401, Orange No. 402, Orange No. 403, Red No. 102, Red No. 104-(1), Red No. 105-(1), Red 106 Red No. 2, Red No. 201, Red No. 202, Red No. 203, Red No. 204, Red No. 205, Red No. 206, Red No. 207, Red No. 208, Red No. 213, Red No. 214, Red No. 215, Red No. 218, Red No. 219, Red No. 220, Red No. 221, Red No. 223, Red No. 225, Red No. 226, Red No. 227, Red No. 228, Red No. 230-(1), Red No. 230-(2), Red No. 23 One or more substances selected from the group consisting of No. 1, Red No. 232, Red No. 3, Red No. 401, Red No. 405, Red No. 501, Red No. 502, Red No. 503, Red No. 504, Red No. 505, Red No. 506, titanium dioxide, iron oxide, chromium oxide, manganese violet, carbon black, metal powder, metal flakes, metal oxide flakes, glass flakes, colored resin particles, plated resin particles, etc.

[0065] <Polyol compounds> Polyol compounds function as diluents and adhesion enhancers for curable artificial nail compositions. Examples of polyol compounds include one or more selected from the group consisting of alkyl polyols, polyester polyols, polyether polyols, acrylic polyols, polybutadiene polyols, and phenolic polyols. Among these, alkyl polyols, polyester polyols, and polyether polyols are preferred. Examples of alkyl polyols include one or more selected from the group consisting of ethylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, neopentyl glycol, cyclohexanedimethanol, trimethylolpropane, pentaerythritol, and the like.

[0066] Examples of polyester polyols include one or more selected from the group consisting of condensation-type polyester polyols, addition-polymerized polyester polyols, and polycarbonate polyols. Condensation-type polyester polyols are obtained by a condensation reaction between one or more diol compounds selected from the group consisting of ethylene glycol, propylene glycol, diethylene glycol, 1,4-butanediol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 1,4-hexanedimethanol, dimer acid diol, polyethylene glycol, etc., and one or more organic polybasic acids selected from the group consisting of adipic acid, isophthalic acid, terephthalic acid, sebacic acid, etc., and preferably have a mass-average molecular weight of 100 to 100,000. Examples of addition-polymerized polyester polyols include polycaprolactone, and preferably have a mass-average molecular weight of 100 to 100,000. Polycarbonate polyols are synthesized by methods such as direct phosgenation of polyols or transesterification with diphenyl carbonate, and their mass-average molecular weight is preferably between 100 and 100,000. Examples of polyether polyols include those obtained by ring-opening polymerization of alkylene oxides.

[0067] <Chain movement agent> Examples of chain transfer agents include one or more selected from the group consisting of mercaptan compounds such as n-butyl mercaptan and n-octyl mercaptan; terpenoid compounds such as limonene, myrcene, α-terpinene, β-terpinene, γ-terpinene, terpinolene, β-pinene, and α-pinene; and α-methylstyrene dimer derivatives. However, the curable artificial nail composition of the present invention does not necessarily have to contain such a chain transfer agent.

[0068] [Uses and physical properties of hardened artificial nail compositions] The curable artificial nail composition of the present invention is less susceptible to curing inhibition by oxygen, suppresses the generation of uncured components on the surface of the cured coating, exhibits excellent non-wipeability, has sufficient hardness and flexibility in the cured coating, and offers excellent application workability.

[0069] The curable artificial nail composition of the present invention is a composition for coating the surface of a nail, similar to so-called general manicures and pedicures. It may also be used to coat the surface of the user's own nail, which may have been sanded or otherwise made uneven as needed. It is particularly suitable for use as a gel nail, and can be used, for example, as a base coat layer (gel base; undercoat) applied directly to the user's nail, an intermediate layer (color coat layer) applied on top of the base coat layer, or a top coat layer applied on top of that. When used as a color coat, it can be used with a variety of colors such as solid colors, glittery colors, metallic colors, dark colors, and light colors by using a coloring agent. The curable artificial nail composition of the present invention reduces the amount of uncured components generated when a cured coating film is formed, and furthermore, the cured coating film has appropriate flexibility, making it particularly preferable to use it as a top coat.

[0070] When forming the cured coating film of the curable artificial nail composition of the present invention, equipment similar to that used for conventional radical polymerizing nail polish cured by ultraviolet light, or general ultraviolet curing equipment can be used.

[0071] The curable artificial nail composition of the present invention should have a viscosity that allows it to be sufficiently applied using an applicator such as a brush. Alternatively, it may have a viscosity that allows it to be applied by inkjet printing or the like. The curable artificial nail composition preferably has a maximum stress of 15.0 MPa or higher at the time of fracture in a tensile test of the cured coating film, more preferably 18.0 MPa or higher, and even more preferably 20.0 MPa or higher. If it is less than 15.0 MPa, it may be prone to peeling due to friction. Furthermore, it is preferable that the strain rate at the time of rupture of the cured coating film be 95.0% or higher, more preferably 97.0% or higher, and even more preferably 100.0%.

[0072] [Covering of nails using a hardening artificial nail composition] The nails coated with the curable artificial nail composition of the present invention may be human fingernails or toenails, or even animal nails such as those of dogs or cats. When applying the curable artificial nail composition of the present invention to a nail or an (uncured) coating applied to a nail, sanding of the application surface is optional. The method of applying the curable artificial nail composition is not particularly limited, and for example, an application tool such as a brush or an application method such as inkjet printing can be used. After applying the curable artificial nail composition of the present invention, it is also possible to enhance its aesthetic appeal by attaching small decorations, powders, etc., to the surface of the coating film of the curable artificial nail composition before it hardens. The curable artificial nail composition of the present invention is less susceptible to curing inhibition by oxygen, suppresses the generation of uncured components on the surface of the cured coating film, exhibits excellent non-wipeability, and the cured coating film has sufficient hardness and flexibility, and has excellent application workability, making it particularly suitable for forming a topcoat layer.

[0073] Using the curable artificial nail composition of the present invention, a layer having the shape of a nail or the like can be created on one side of a sheet, and after bringing this layer into contact with (transferring) the nail surface, the sheet can be peeled off or, without peeling it off, cured by irradiation with ultraviolet light. According to the method of providing a layer on the sheet surface using a curable artificial nail composition in advance and transferring it, it is possible to coat a uniform and accurate pattern on the surface of the nail without using an applicator such as a pen, and there is no need to wash the applicator even after use.

[0074] The curing of the curable artificial nail composition after coating can be carried out, for example, using a known ultraviolet curing device. Although the irradiation energy required for curing varies depending on the composition of the curable artificial nail composition, the irradiation energy (integrated light amount) by its light irradiation is 5 mJ / cm 2 or more, preferably 10 mJ / cm 2 or more, and 1000 mJ / cm 2 or less, preferably 800 mJ / cm 2 or less. If the irradiation energy is within this range, a nail art having sufficient adhesion and abrasion resistance can be obtained. As the light source, for example, an ultraviolet light source such as a mercury lamp, a metal halide lamp, an ultraviolet light emitting diode (UV-LED), or an ultraviolet laser diode (UV-LD) can be used. Among them, from the viewpoints of small size, long life, high efficiency, and low cost, an ultraviolet light emitting diode (UV-LED) and an ultraviolet laser diode (UV-LD) are preferable.

Example

[0075] Examples are given below to explain the present invention in more detail, but the present invention is not limited only to these examples. Unless otherwise specified, "part" means "part by mass" and "%" means "mass%".

[0076] [Examples 1 to 5, Comparative Examples 1 to 30] The components shown in Tables 1 to 4 were added to a container in the proportions (parts by mass) shown in Tables 1 to 4, and the mixture was heated to 50°C while being stirred with a dissolver. After stirring, the mixture was allowed to stand at 80°C for 2 hours to remove air bubbles, and a curable artificial nail composition was obtained. All of these steps were performed under light shielding. The obtained curable artificial nail composition was evaluated for surface uncuring, bending, and texture based on the <Evaluation> described below. The results are shown in Tables 1 to 4.

[0077] <Ingredients> The components in Tables 1 to 4 are as follows: A1: A hexamethylene isocyanate-dipentaerythrityl pentaacrylate-polyethylene glycol monoacrylate urethane oligomer having six radically polymerizable unsaturated double bonds in one molecule. A2: A dicyclohexylmethane 4,4'-diisocyanate-based urethane (meth)acrylate (mass-average molecular weight 2,400) containing six radically polymerizable unsaturated double bonds per molecule. A3: A 1,3-bis(isocyanatomethyl)cyclohexane-based urethane (meth)acrylate (mass-average molecular weight 2,000) containing six radically polymerizable unsaturated double bonds per molecule. A4: A dicyclohexylmethane 4,4'-diisocyanate-based urethane (meth)acrylate containing four radically polymerizable unsaturated double bonds in one molecule (mass-average molecular weight 1,800). A5: An isophorone diisocyanate-1,4-butanediol-hydroxyethyl methacrylate-based urethane (meth)acrylate (mass-average molecular weight 3,000) containing two radically polymerizable unsaturated double bonds per molecule. A6: An isophorone diisocyanate-polypropylene glycol-hydroxyethyl methacrylate-based urethane (meth)acrylate (mass-average molecular weight 4,000) having two radically polymerizable unsaturated double bonds in one molecule. A7: An isophorone diisocyanate-polytetramethylene ether glycol-neopentyl glycol-hydroxyethyl acrylate-based urethane (meth)acrylate (mass-average molecular weight 1,200) having two radically polymerizable unsaturated double bonds in one molecule.

[0078] B1: Polycarbonate polyurethane methacrylate obtained from hydroxyethyl methacrylate, isophorone diisocyanate, and polycarbonate diol (mass-average molecular weight 27,000) HEMA: 2-hydroxyethyl methacrylate PEMP: Pentaerythritol tetrakis(3-mercaptopropionate) HCl:1-Hydroxycyclohexylphenyl ketone TPO:2,4,6-trimethylbenzoyldiphenylphosphine oxide IBXA: Isobornyl acrylate DMAA: Dimethylacrylamide TMPMA: Trimethylolpropane Trimethacrylate ACMO: Acryloylmorpholine TOC: α-tocopherol Vio-200: Purple 201

[0079] <Surface Uncured Evaluation> A 100 μm thick curable artificial nail composition coating was prepared on a PVC sheet, and the cured coating obtained by curing it for 30 seconds with a 36W multi-type (UV+LED) lamp was used as an evaluation sample. The surface of the cured coating film was touched, and the amount of uncured components remaining was evaluated sensorily according to the following criteria. A: A state in which there are absolutely no uncured components. A / B: A state between A and B B: A state in which there are almost no uncured components. B / C: An intermediate state between B and C. C: A state in which tackiness can be felt when touched with a finger. C / D: An intermediate state between C and D. D: A sticky feeling In this invention, A to C are acceptable, while C / D and D are unacceptable.

[0080] <Folding evaluation> A 100 μum curable artificial nail composition coating was prepared on a 7 cm x 9 cm PVC board, and the cured coating obtained by curing it for 30 seconds with a 36 W multi-type (UV + LED) lamp was used as the evaluation sample. The behavior of PVC sheets when bent so that their short sides touch was observed and evaluated according to the following criteria. A: Nothing changed (flexible). D: Cracks occurred (lack of flexibility) E: Peeling occurred (lack of flexibility) D / E: Cracks and peeling occurred (no flexibility) In this invention, A is acceptable, while D, E, and D / E are unacceptable.

[0081] <Texture Evaluation> The ease of application of the curable artificial nail composition to a transparent chip was evaluated sensorily according to the following criteria. 5: Very high viscosity (hard texture) 4: High viscosity (hard texture) 3: The easiest condition to apply 2: Low viscosity (hard texture) 1: Very low viscosity (loose texture) In this invention, 3 is acceptable, while 5, 4, 2, and 1 are unacceptable.

[0082] [Table 1]

[0083] [Table 2]

[0084] [Table 3]

[0085] [Table 4]

[0086] As can be seen from the examples and comparative examples in Tables 1 to 4, the present invention provides a curable artificial nail composition that suppresses the generation of uncured components on the surface of the cured coating, exhibits excellent non-wipeability, and provides a cured coating that has sufficient hardness and flexibility. As can be seen from the examples and comparative examples in Table 1, the curable artificial nail composition of the present invention exhibits suppressed temperature rise during curing, and yellowing of the cured coating film formed after the curable artificial nail composition has been stored is suppressed.

Claims

1. (A) Radical polymerizable urethane oligomers having a mass-average molecular weight of 500 or more and less than 5,000, (B) Radical polymerizable urethane oligomers having a mass-average molecular weight of 5,000 or more and 100,000 or less. (C) A radical polymerizable monomer having a hydroxyl group, (D) Polyfunctional thiol compounds, and (E) Polymerization initiator, It contains, The (A) radical polymerizable urethane oligomer having a mass average molecular weight of 500 or more and less than 5,000 contains (A1) a urethane oligomer having a mass average molecular weight of 500 or more and less than 2,700 and having 3 or more radical polymerizable groups in one molecule, and (A2) a urethane oligomer having a mass average molecular weight of 2,700 or more and less than 5,000 and having 2 radical polymerizable groups in one molecule. (B) A curable artificial nail composition in which the content of a radical polymerizable urethane oligomer having a mass-average molecular weight of 5,000 or more and 100,000 or less is 1.0% by mass or more and 35.0% by mass or less, based on 100% by mass of the total amount of components of the curable artificial nail composition.

2. (F) The curable artificial nail composition according to claim 1, comprising a polymerization inhibitor.

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