JP2022111991A - Photocurable artificial nail composition - Google Patents

Abstract

To provide a photocurable artificial nail composition that gives a cured coating capable of adhering (bonding) to an adherend and keeping the adhering state for a long time and also has advantages such as high curability and the beauty of the cured coating.SOLUTION: A photocurable artificial nail composition contains (a) a radical-polymerizable phosphate compound having an acrylate group, (b) a radical-polymerizable compound having a methacrylate group and having no phosphorus atom, and (c) a photopolymerization initiator.SELECTED DRAWING: None

Description

The present invention relates to photocurable artificial nail compositions.

Nail art, in which the natural nails of hands and feet are decorated, or artificial nails are glued and decorated, is gaining popularity. Further, an artificial nail is formed on the nail for reinforcement to prevent cracking and peeling of the nail due to external force.
In order to decorate and reinforce such nails, resin-containing materials called manicures, pedicures and sculptures are applied to the nails.

Recently, a photocurable artificial nail composition called gel nail has attracted attention as a material used for decorating or reinforcing nails. A gel nail is a photocurable gel-like nail coating material (photocurable artificial nail composition), and includes, for example, a (meth)acrylate oligomer and a (meth)acrylic monomer. Gel nails are applied to nails and cured by irradiating them with ultraviolet rays to form a crosslinked polymer film through a radical polymerization reaction.

Until now, photocurable artificial nail compositions such as gel nails have been developed from the viewpoint of adhesion of the cured coating film to the base material (adhesive force to the nail), adhesion sustainability, curability, aesthetic appearance of the cured coating film, etc. has been mainly studied. However, conventional photocurable artificial nail compositions have been required to have further improved properties in terms of adhesion of the cured coating film to the substrate (adhesive force to the nail) and adhesion durability. Further, the photocurable artificial nail composition is required to have properties such as curability and aesthetic appearance of the cured coating film.

In photocurable artificial nail compositions such as gel nails, the following studies have been made so far in order to improve the adhesion of the cured coating film to the substrate (adhesive force to the nail) and adhesion durability.
Patent Document 1 discloses (a) a compound having at least one radically polymerizable unsaturated double bond in the molecule, (b) an acidic phosphorous compound having at least one radically polymerizable unsaturated double bond in the molecule. An artificial nail compound is described that includes a compound and (c) a radical polymerization initiator.

Patent Document 2 describes a photocurable artificial nail composition containing a urethane (meth)acrylate oligomer, a radically polymerizable compound and a photopolymerization initiator. This composition specifically uses a "radically polymerizable phosphoric acid compound having a methacrylate group" such as methacryloxyethylhexanoate phosphate and trismethacryloyloxyethyl acid phosphate as the radically polymerizable compound. A radically polymerizable phosphoric acid compound having an acrylate group is not used.

JP-A-2010-53097 JP 2017-197532 A

The problem to be solved by the present invention is that the cured coating film has excellent adhesion to the substrate (adhesive force to the nail) and adhesion sustainability, and has excellent properties such as curability and the aesthetic appearance of the cured coating film. To obtain a natural artificial nail composition. Another object of the present invention is to obtain a photocurable artificial nail composition which prevents a cured coating film formed on the nail from clouding over time, and which is excellent in properties such as curability and appearance of the cured coating film.

The present inventors have made intensive studies to solve the above problems, and as a result, have found that the above problems can be solved by providing a photocurable artificial nail composition having a specific composition, and have completed the present invention. rice field.
Specifically, it is as follows.
Item 1: Photocuring containing (a) a radically polymerizable phosphoric acid compound having an acrylate group, (b) a radically polymerizable compound having a (meth)acrylate group and no phosphorus atom, and (c) a photopolymerization initiator artificial nail composition.
Item 2: The photocurable artificial nail composition according to Item 1, wherein (a) the radically polymerizable phosphoric acid compound having an acrylate group is a radically polymerizable phosphoric ester compound having an acrylate group.
Item 3: The photocuring according to Item 1 or 2, wherein (a) the radically polymerizable phosphoric acid compound having an acrylate group is 2-acryloyloxyethyl phosphate and/or bis(2-acryloyloxyethyl) phosphate. artificial nail composition.
Item 4: Any one of Items 1 to 3, wherein (b) the radically polymerizable compound having a (meth)acrylate group and no phosphorus atom is a radically polymerizable oligomer having a (meth)acrylate group. of a photocurable artificial nail composition.
Item 5: Item, wherein the content of (a) the radically polymerizable phosphoric acid compound having an acrylate group is more than 0% by mass and 4.4% by mass or less with respect to the total amount of the constituent components of the photocurable artificial nail composition. The photocurable artificial nail composition according to any one of 1 to 4.

The photocurable artificial nail composition of the present invention is excellent in adhesiveness of the cured coating film to the substrate (adhesive force to the nail) and adhesion durability, and is also excellent in properties such as curability and appearance of the cured coating film. exerts a remarkable effect.

The photocurable artificial nail composition of the present invention is described below.
The photocurable artificial nail composition of the present invention comprises a radically polymerizable phosphoric acid compound having an acrylate group, a radically polymerizable compound having a (meth)acrylate group and no phosphorus atom, and a photopolymerization initiator.
In the photocurable composition of the present invention, by containing a radically polymerizable phosphoric acid compound having an acrylate group, the adhesion of the cured coating film to the substrate (adhesion to the nail) and adhesion durability are improved. Although the mechanism and the like are unknown, the present inventors presume as follows.
In general, the acrylate group has less steric hindrance and higher curability than the methacrylate group. It is considered that the adhesion to the substrate (adhesion to the nail) and the adhesion durability are improved. It should be noted that the present invention is not limited to this conjecture.
Further, in the photocurable artificial nail composition of the present invention, the content of the radically polymerizable phosphoric acid compound having an acrylate group is adjusted to a specific range (0 mass %, preferably 0.1% by mass or more, and 4.4% by mass or less, preferably 4.3% by mass or less), the photocurable artificial nail composition coating film formed on the nail is Although the mechanism and the like that can prevent cloudiness over time (whitening over time) are unknown, the present inventors speculate as follows.
In general, a radically polymerizable phosphoric acid compound having an acrylate group is often provided as a mixture of a compound in which one hydroxyl group is bonded to a phosphorus atom and a compound in which two hydroxyl groups are bonded to a phosphorus atom. When the radical polymerizable phosphoric acid compound having an acrylate group and the nail bond (hydrogen bond), one hydroxyl group bonded to the phosphorus atom contributes, so the hydroxyl group bonded to the phosphorus atom becomes excessive. there is It is believed that the excessive hydroxyl groups react with the moisture that evaporates from the nail, causing the cured coating film to become cloudy over time. This is because white turbidity of the cured coating film does not occur immediately after application, and white turbidity does not occur over time in a system that does not contain a radically polymerizable phosphoric acid compound having an acrylate group. It is believed that this is due to the reaction between excess hydroxyl groups from the radically polymerizable phosphoric acid compound having a group and moisture that evaporates from the nail. From this, by setting the content of the radically polymerizable phosphoric acid compound having an acrylate group to a specific range with respect to the total amount of the constituent components of the photocurable artificial nail composition, the photocurable artificial nail formed on the nail It is thought that clouding of the nail composition coating film over time can be prevented. It should be noted that the present invention is not limited to this conjecture.

Below, (a) a radically polymerizable phosphoric acid compound having an acrylate group, (b) a radically polymerizable compound having a (meth)acrylate group and not having a phosphorus atom, and (c) a photopolymerization initiator, a photocurable Artificial nail compositions are described in detail.
As used herein, (meth)acrylate means both acrylate and methacrylate.

[Radical Polymerizable Phosphate Compound Having Acrylate Group]
A radically polymerizable phosphoric acid compound having an acrylate group is a radical having an acrylate group and a phosphoric acid group (-P(=O)(OH) ₂ group or -P(=O)(OH)- group) in the molecule. It is not particularly limited as long as it is a polymerizable phosphoric acid compound.
For example:
_CH2 =CH-COO-R1 ^- P(=O)(OH) _2
CH2 =CH-COO-R2 ^- P(=O)(OH)-R3 ^- OCO-CH= _CH2
(In the formula, R ¹ , R ² and R ³ represent divalent organic groups.)
One or more selected from the group consisting of compounds represented by:

Examples of such radically 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 Phosphate, Acryloyloxypropyl Phosphate, Acryloyloxybutyl Phosphate, Acryloyloxypentyl Phosphate, Acryloyloxyhexyl Phosphate, Phosphoric Acid Acryloyloxyethyl Caproate, Acryloyloxypropyl Caprophosphate, Acryloyloxybutyl Caproate Phosphate, Acryloyloxypentyl Caproate Phosphate, Acryloyloxyhexyl Caproate Phosphate, Acryloyloxyethyl Caprylate Phosphate, Caprylic Acid Phosphate acryloyloxypropyl, 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 One or more selected from the group consisting of monoacrylates, ethylene oxide-modified phosphoric acid diacrylates, propylene oxide-modified phosphoric acid diacrylates, phosphoric acid-modified epoxy acrylates, and the like can be mentioned. As the radically polymerizable phosphoric acid compound having an acrylate group, for example, a radically polymerizable phosphate ester compound having an acrylate group can be used.

In the photocurable artificial nail composition of the present invention, the content of the radically polymerizable phosphoric acid compound having an acrylate group is not particularly limited. For example, more than 0% by mass, preferably 0.01% by mass or more, more preferably 0.1% by mass or more, and still more preferably 0.5% by mass or more, relative to the total amount of the constituent components of the photocurable artificial nail composition. For example, it can be 10.0% by mass or less, preferably 7.0% by mass or less, and more preferably 5.0% by mass or less. By containing a radically polymerizable phosphoric acid compound having an acrylate group, the photocurable artificial nail composition of the present invention can improve adhesion to nails.
In the photocurable artificial nail composition of the present invention, the content of the radically polymerizable phosphoric acid compound having an acrylate group is more than 0% by mass, preferably 0%, based on the total amount of constituent components of the photocurable artificial nail composition. .1% by mass or more and 4.4% by mass or less, preferably 4.3% by mass or less, the photocurable artificial nail composition coating film formed on the nail becomes cloudy over time. (cloudiness over time) can be prevented.

[Radical polymerizable compound having (meth)acrylate group and no phosphorus atom]
The radically polymerizable compound having a (meth)acrylate group and no phosphorus atom is a radically polymerizable compound having one or more (meth)acrylate groups in the molecule and having no phosphorus atom in the molecule. There are no particular restrictions, and one type can be used alone or two or more types can be used in combination.
The number of (meth)acrylate groups contained in one molecule is not particularly limited, but from the viewpoint of the curability of the photocurable artificial nail composition, the hardness of the cured coating film, etc., it is 1 to 10, preferably 1 to 8. is one. Also, the number of (meth)acrylate groups can be confirmed by analysis using infrared absorption spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), gas chromatography mass spectrometry (GC/MS), or the like.

Examples of the radically polymerizable compound having a (meth)acrylate group and no phosphorus atom include, for example, a radically polymerizable oligomer having a (meth)acrylate group and no phosphorus atom (hereinafter referred to as "having a (meth)acrylate group and a radically polymerizable monomer having a (meth)acrylate group and no phosphorus atom (hereinafter sometimes referred to as a "radical polymerizable monomer").
In the present invention, as the radically polymerizable compound having a (meth)acrylate group and no phosphorus atom, one or more oligomers having a (meth)acrylate group and one or more radically polymerizable monomers are mixed. It is preferable to use

In the photocurable artificial nail composition of the present invention, the content of the radically polymerizable compound having a (meth)acrylate group and no phosphorus atom is not particularly limited. For example, 1% by mass or more, preferably 10% by mass or more, more preferably 20% by mass or more, for example 99% by mass or less, preferably 98% by mass or less, relative to the total amount of the constituent components of the photocurable artificial nail composition. , more preferably 95% by mass or less.

<Oligomer having (meth)acrylate group>
The oligomer having a (meth)acrylate group used as a radical polymerizable compound having a (meth)acrylate group and having no phosphorus atom is not particularly limited as long as it is an oligomer having one or more (meth)acrylate groups. The number of (meth)acrylate groups contained in one molecule is not particularly limited, but from the viewpoint of the curability of the photocurable artificial nail composition, the hardness of the cured coating film, etc., it is 1 to 10, preferably 2 to 8. is one.
The number of (meth)acrylate groups can be confirmed by analysis using infrared absorption spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR), gas chromatography mass spectrometry (GC/MS), or the like.

The radically polymerizable phosphoric acid compound having an acrylate group contained in the photocurable artificial nail composition of the present invention has high reactivity and generates high curing heat during curing. For this reason, by including an oligomer having a methacrylate group, which has relatively low reactivity and generates less curing heat during curing than a radically polymerizable phosphoric acid compound having an acrylate group, a photocurable artificial It is preferable to adjust the reactivity of the nail composition to lower the curing heat of the photocurable artificial nail composition. Thereby, the curing heat of the photocurable artificial nail composition can be set to, for example, 45° C. or lower, preferably 43° C. or lower, and more preferably 40° C. or lower.

According to the findings of the present inventors, in photocurable artificial nail compositions, curing heat is generated by reaction between (meth)acrylate groups and radicals. Therefore, if a component with a high degree of polymerization (large weight average molecular weight) such as a (meth)acrylate oligomer is used, the number of (meth)acrylate groups per unit mass decreases, and the number of reaction sites per unit mass decreases. , the heat of curing can be controlled (reduced). On the other hand, the use of polyfunctional (meth)acrylates tends to increase the heat of curing.
That is, the heat of curing can be reduced by increasing the content of oligomers having a high degree of polymerization (large molecular weight), which increases the degree of polymerization of oligomers having (meth)acrylate groups. On the other hand, the heat of curing can be increased by using an oligomer having a large number of (meth)acrylate groups, decreasing the degree of polymerization of the oligomer, or increasing the content of an oligomer with a low degree of polymerization (low molecular weight).
In addition, since the acrylate group does not have a bulky molecular structure, its reactivity is higher than that of the methacryloyl group. On the other hand, curing heat tends to increase.
In the photocurable artificial nail composition of the present invention, for example, an oligomer having a methacrylate group can be used as the oligomer having a (meth)acrylate group.

The oligomer having a (meth)acrylate group is not particularly limited, but for example
A (meth)acrylate group having at least one selected from the group consisting of a urethane bond, a bond resulting from a ring-opening reaction of an epoxy group, an ester bond, an ether bond, a urea bond, a carbonate bond, and an amide bond in the main skeleton (main chain). an oligomer having
Oligomers having a (meth)acrylate group whose main skeleton (main chain) has a molecular chain obtained by polymerization of one or more monomers selected from the group consisting of styrene, (meth)acrylic, olefin, and diene monomers,
and the like.

Of these,
(a) urethane (meth)acrylate oligomer (oligomer having a (meth)acrylate group having a urethane bond in its main skeleton),
(b) an epoxy (meth)acrylate oligomer having a molecular chain generated by a ring-opening reaction of an epoxy group;
(c) an ester (meth)acrylate oligomer (having an ester bond in its main skeleton (oligomer having a methacrylate group),
(d) an ether (meth)acrylate oligomer (an oligomer having a (meth)acrylate group having an ether bond in its main skeleton),
Use of one or more selected from the group consisting of etc. is advantageous in terms of adhesion and the like.
As the oligomer having a (meth)acrylate group, either commercially available products or synthetic products may be used. Further, in the present invention, from the viewpoint of nail adhesion and durability of the photocurable resin composition and/or its cured coating film, even if it contains one or more oligomers having a urethane (meth)acrylate group. good.
The oligomer having a (meth)acrylate group can also be used by mixing with an oligomer other than the oligomer having a (meth)acrylate group.

(urethane (meth)acrylate oligomer)
A urethane (meth)acrylate oligomer is formed by, for example, reacting a polyol with a polyisocyanate to form an isocyanate group-containing urethane prepolymer, and a compound (hydroxyalkyl (Meth)acrylate, (meth)acrylic acid, etc.) can be synthesized, but the method is not limited to this method.
Commercial products include, for example, AH-600, AT-600, UA-306H, UF-8001G (manufactured by Kyoeisha Chemical Co., Ltd.), RUA-071, RUA-003VE, RUA-075, RUA-048 (Asia Chemical Industry Co., Ltd.) ), UA-4200, UA200PA, UA-33H, UA-1100H, SUA TH1, SUA TH2 (manufactured by Shin-Nakamura Chemical Co., Ltd.), UV-3310B (manufactured by Mitsubishi Chemical Co., Ltd.), UN-9000PEP, UN-9200A, AU- 2040 (manufactured by Tokushiki), KUA-PC2I (manufactured by KSM), artresin UN-6303, UN-9200A, UN-900PEP (manufactured by Negami Kogyo) and the like. It is not limited to these.

The use of urethane (meth)acrylate oligomers in photocurable artificial nail compositions is preferred because a cured coating film having excellent stretchability, adhesion and strength can be obtained.
One or more urethane (meth)acrylate oligomers that can be used in the present invention include non-aromatic polyether skeletons, aromatic polyether skeletons, non-aromatic polycarbonate skeletons, aromatic polycarbonate skeletons, non-aromatic It can be used by selecting from those having one or more selected from the group consisting of aromatic polyester skeletons and aromatic polyester skeletons. Among them, those having one or more of a non-aromatic polyether skeleton and a (non-)aromatic polycarbonate skeleton are preferable.

For example, a urethane (meth)acrylate oligomer having one or more non-aromatic polyether skeletons is obtained by adding a (meth)acrylic compound having a hydroxyl group to an isocyanate group-containing polyether urethane prepolymer. 10% or more of the total number of isocyanate groups in is subjected to an addition reaction with the (meth)acrylic compound having a hydroxyl group.
Here, the isocyanate group-containing polyether urethane prepolymer is obtained by reacting a polyol compound having an alkylene group having 3 or more carbon atoms with a polyisocyanate, and has a weight average molecular weight of, for example, 400 or more and 30,000 or less. is. Polypropylene polyol is preferable as the polyol compound. The polyisocyanate includes one or more selected from the group consisting of non-aromatic polyisocyanates such as isophorone diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isocyanurate products thereof, biuret products thereof, and the like.

(Epoxy (meth)acrylate oligomer)
An epoxy (meth)acrylate oligomer having a molecular chain generated by a ring-opening reaction of an epoxy group is synthesized, for example, by reacting a polyfunctional epoxy resin with a (meth)acrylate having a functional group that reacts with the epoxy group. It is possible, but not limited to this method.
Commercially available products include, for example, EBECRYL 1259, 605, 1606 (manufactured by Daicel Cytec), EPOXY ESTER 3000A, 3000MK, 3002A (N), 3002M (N), 40EM (manufactured by Kyoeisha Chemical Co., Ltd.) and the like. One or more of the above may be mentioned, but are not limited to these.

(Ester (meth)acrylate oligomer)
An ester (meth)acrylate oligomer having an ester bond is, for example, a hydroxyl group and a (meth)acrylate in the molecule with respect to the carboxyl group and/or hydroxyl group of the ester-based oligomer obtained by reacting a polyol and a polyvalent carboxylic acid. It can be synthesized by adding a compound having a group and/or an acrylic compound having (meth)acrylic acid or a carboxyl group, but is not limited to this method.
Commercially available products include, for example, Aronix (registered trademark) M-6100, M-6200, M-6250, M-6500, M-7100, M-7300K, M-8030, M-8060, M-8100, M- One or more selected from the group consisting of 8530, M-8560, M-9050 (manufactured by Toagosei Co., Ltd.), UV-3500BA, UV3520TL, UV-3200B, UV-3000B (manufactured by Mitsubishi Chemical Corporation), etc. , but not limited to these.

(Ether (meth)acrylate oligomer)
Ether (meth)acrylate oligomers having ether linkages, for example, have hydroxyl groups and (meth ) compounds having an acrylate group, (meth)acrylic acid, and compounds having a carboxyl group and a (meth)acrylate group in the molecule, etc., which can be synthesized by addition of one or more selected from the group consisting of this method. is not limited to
Commercially available products include, for example, UV-6640B, UV-6100B, UV-3700B (manufactured by Mitsubishi Chemical Corporation), Light Acrylate (registered trademark) 3EG-A, 4EG-A, 9EG-A, 14EG-A, PTMGA-250. , BP-4EA, BP-4PA, BP-10EA, light ester 4EG, 9EG, 14EG (manufactured by Kyoeisha Chemical Co., Ltd.), EBECRYL (registered trademark) 3700 (manufactured by Daicel-Cytec), etc. One or more selected from the group consisting of However, it is not limited to these.

(Weight average molecular weight and content of oligomer having (meth)acrylate group)
The weight average molecular weight of the (meth)acrylate group-containing oligomer is not particularly limited. For example, it is 1,000 or more, preferably 2,000 or more, more preferably 3,000 or more, and for example, 100,000 or less, preferably 30,000 or less, more preferably 20,000 or less. By setting the weight-average molecular weight range to such a range, the durability of the cured coating film can be improved while maintaining a low viscosity.

In the photocurable artificial nail composition of the present invention, the content of the oligomer having (meth)acrylate groups is not particularly limited. For example, 10% by mass or more, preferably 20% by mass or more, for example 90% by mass or less, preferably 70% by mass or less, more preferably 50% by mass or less, relative to the total amount of the constituent components of the photocurable artificial nail composition. can be
Moreover, the content of the oligomer having a (meth)acrylate group with respect to the total amount of the radically polymerizable compound having a (meth)acrylate group and having no phosphorus atom is not particularly limited either. For example, it is 0% by mass or more, preferably 5% by mass or more, more preferably 20% by mass or more, and can be, for example, 100% by mass or less, preferably 50% by mass or less.

<Radical polymerizable monomer>
Examples of radically polymerizable monomers include radically polymerizable monomers having (meth)acrylate groups (hereinafter sometimes referred to as "(meth)acrylate monomers") and radically polymerizable unsaturated groups other than (meth)acrylate groups. A compound having

((meth)acrylate monomer)
The (meth)acrylate monomer is not particularly limited as long as it has one or more (meth)acrylate groups and does not have a phosphorus atom in the molecule. The number of (meth)acrylate groups contained in one molecule is not particularly limited, but from the viewpoint of the curability of the photocurable artificial nail composition, the hardness of the cured coating film, etc., it is 1 or more, for example 10 or less. , preferably 8 or less, more preferably 6 or less.
In the present invention, it is preferable to use one or more selected from (meth)acrylate monomers having one (meth)acrylate group as the (meth)acrylate monomer. A mixture of one or more selected from (meth)acrylate monomers having one (meth)acrylate group and one or more selected from (meth)acrylate monomers having two or more (meth)acrylate groups is used. is preferred.

(Meth)acrylate monomers having one (meth)acrylate group include, for example, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, ) acrylate, isobutyl (meth)acrylate, t-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, neopentyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate , phenyl (meth) acrylate, benzyl (meth) acrylate, N-acryloyloxyethyl hexahydrophthalimide and other monohydric alcohol esters with (meth) acrylic acid; acrylamide, hydroxyethyl acrylamide, dimethyl acrylamide, diethyl acrylamide, methacryl amide, N-methyl (meth)acrylamide, N-hydroxyethyl (meth)acrylamide, N-ethyl (meth)acrylamide, N-methylol (meth)acrylamide, N-methoxymethyl (meth)acrylamide, N-butoxymethyl (meth)acrylamide ) 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-butyl (meth)acrylamide, 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, N,N-dimethyl (meth)acrylate group-containing amide compounds such as aminoethyl (meth)acrylamide; hydroxyl group-containing (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and hydroxybutyl (meth)acrylate; Nitrogen-containing alkyls such as N,N-dimethylaminoethyl (meth)acrylate, N,N-diethylaminoethyl (meth)acrylate, and Nt-butylaminoethyl (meth)acrylate glycidyl (meth)acrylate; 4-(meth)acryloyloxymethyl-2-cyclohexyl-1,3-dioxolane, adamantyl (meth)acrylate, (2-methyl-2-ethyl-1,3- Dioxolan-4yl)methyl (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, (2-isobutyl-2-methyl-1,3-dioxolan-4yl)methyl (meth)acrylate, (2-ethyl- 2-methyl-1,3-dioxolan-4yl)methyl (meth)acrylate, (1,4-dioxaspiro[4,5]decane-2yl)methyl (meth)acrylate, tetrafurfuryl alcohol oligo(meth)acrylate , alkoxylated tetrahydrofurfuryl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, (3-ethyloxetan-3-yl)methyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate glycidyl ether, (meth)acryloyl Morpholine, N-(meth)acryloyloxyethylhexahydrophthalimide, pentamethylpiperidyl (meth)acrylate, isocyanuric acid di(meth)acrylate, isocyanuric acid tri(meth)acrylate, triazine tri(meth)acrylate, N-( One or more selected from the group consisting of heterocyclic ring-containing (meth)acrylates such as meth)acryloxysuccinimide, N-(meth)acryloxyphthalimide, and the like.

Of these (meth)acrylate monomers having one (meth)acrylate group, (i) 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 ( Esterified product of monohydric alcohol such as meth)acrylate and (meth)acrylic acid,
(ii) hydroxyl group-containing (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate and hydroxybutyl (meth)acrylate;
One or more types selected from the group consisting of are preferable.

(Meth)acrylate monomers having two or more (meth)acrylate groups include, for example, 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, pentaerythritol di(meth)acrylate, bisphenol A ethylene oxide-modified di(meth)acrylate, ethoxylated bisphenol A di(meth)acrylate, propoxylated Di(meth)acrylate monomers such as bisphenol A di(meth)acrylate (isopropylidenediphenyl bis(oxyhydroxypropyl methacrylate), etc.), propoxylated ethoxylated bisphenol A di(meth)acrylate; 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, Tri(meth)acrylate monomers such as ε-caprolactone-modified tris(acryloxyethyl)isocyanurate; tetra(meth)acrylate monomers such as pentaerythritol tetra(meth)acrylate; dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa Polypentaerythritol (meth)acrylate such as (meth)acrylate, tripentaerythritol (meth)acrylate, tetrapentaerythritol (meth)acrylate, ethoxylated isocyanuric acid triacrylate, ethoxylated pen (meth)acrylate monomers having 4 or more (meth)acrylate groups such as taerythritol tetraacrylate; and the like.

で表されるプロポキシ化ビスフェノールＡジメタクリレート、トリメチロールプロパントリ（メタ）アクリレート、ペンタエリスリトールトリ（メタ）アクリレート、ペンタエリスリトールテトラ（メタ）アクリレート、ジペンタエリスリトールペンタ（メタ）アクリレート、ジペンタエリスリトールヘキサ（メタ）アクリレート等からなる群より選ばれる１種類以上を使用することが好ましい。 Among the (meth)acrylate monomers having two or more of these (meth)acrylate groups, 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, formula below

Propoxylated bisphenol A dimethacrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa ( It is preferable to use one or more selected from the group consisting of meth)acrylates and the like.

(Compound having radically polymerizable unsaturated group other than (meth)acrylate group)
(Meth) Examples of compounds having radically polymerizable unsaturated groups other than acrylate groups include, for example, vinyl groups, vinyl ether groups, allyl groups, and other radically polymerizable unsaturated groups (polymerizable carbon-carbon double bonds functional group).
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.

The content of the radically polymerizable monomer in the photocurable artificial nail composition of the present invention is, for example, 1% by mass or more, preferably 10% by mass or more, and is, for example, 90% by mass or less, preferably 80% by mass or less. can be contained as
Further, by adjusting the type and amount of the radically polymerizable monomer contained in the photocurable artificial nail composition, the reactivity and curing heat of the photocurable artificial nail composition can be adjusted.
In the present invention, as the radically polymerizable monomer, a radically polymerizable monomer having a functional group such as a (meth)acrylate monomer having a hydroxyl group, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate The use of a (meth)acrylate compound having a cyclic structure in the molecule such as (meth)acryloylmorpholine improves the adhesion of the cured coating film of the photocurable artificial nail composition to the substrate (adhesive force to the nail). , durability of adhesion, curability, appearance of the cured coating film, and the like.

<Photoinitiator>
A photopolymerization initiator generates radicals when irradiated with light having a wavelength emitted from a light source for photocuring. For example, from the group consisting of acylphosphine oxide, α-hydroxyalkylphenone, benzoin ether, benzyl ketal, acid ester, α-aminoalkylphenone, benzophenone, thioxanthone, titanocene, quinone, etc. One or more photopolymerization initiators may be selected.
The photopolymerization initiator can impart good curability to the photocurable artificial nail composition even when irradiated with light using various light sources including a UV-LED light source.

Among these, the acylphosphine oxide-based photopolymerization initiator generates radicals upon irradiation with ultraviolet rays having a wavelength of 365 nm or more and 405 nm or less emitted from a commonly used UV-LED light source. Therefore, even when curing is performed by irradiating light using various light sources including a UV-LED light source, good curability can be imparted. Furthermore, when curing is performed by irradiating light using a UV-LED light source, yellowing (yellowing) of the cured coating film can be prevented.
Examples of acylphosphine oxide photopolymerization initiators include 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, bis(2,6-dimethoxy benzoyl)-2,4,4-trimethylpentylphosphine oxide and the like.
In particular, 2,4,6-trimethylbenzoyldiphenylphosphine oxide can be preferably used in the present invention since it also functions as a skin conditioning agent.

Examples of photopolymerization initiators other than acylphosphine oxide photopolymerization initiators include 2,4-diethylthioxanthone, 2-isopropylthioxanthone, thioxanthone, 2-chlorothioxanthone, isopropylthioxanthone, and 1-chloro-4-propylthioxanthone. , 3-[3,4-dimethyl-9-oxo-9H-thioxanthone-2-yl-oxy]-2-hydroxypropyl-N,N,N-trimethylammonium chloride, fluorothioxanthone, 2-benzyl-2-dimethyl amino-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-diphenylsulfide, 1,2-octanedione, 1-(4-(phenylthio)-2,2-( O-benzoyl oxime)) 1-hydroxycyclohexylphenyl ketone, benzoin ethyl ether, benzyl dimethyl ketal, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone (IRGACURE 184) , 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 2-hydroxy-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, 2-hydroxy-1-{4- [4-(2-hydroxy-2-methylpropionyl)-benzyl]phenyl}-2-methylpropane, benzophenone, 4-phenylbenzophenone, isophthalphenone, methyl phenylglyoxylate, ethylanthraquinone, phenanthrenequinone, and camphorquinone, One or more selected from the group consisting of 1-hydroxy-cyclohexyl-phenyl-ketone and the like.

In the present invention, it is preferable to use a photopolymerization initiator containing an acylphosphine oxide photopolymerization initiator. It is preferred to use an initiator.

In the photocurable artificial nail composition of the present invention, the content of the photopolymerization initiator is not particularly limited. For example, 0.05% by mass or more, preferably 0.07% by mass or more, more preferably 0.1% by mass or more, for example 5.0% by mass, based on the total amount of the constituent components of the photocurable artificial nail composition. Below, preferably 4.0% by mass or less, more preferably 3.0% by mass or less. If the content exceeds 5.0% by mass, the cured coating film may become brittle due to a decrease in the molecular weight of the cured coating film, and the cured coating film of the photocurable artificial nail composition may turn yellow (yellowing). There is a risk. If the content is less than 0.05% by mass, it may take a long time to cure the photocurable artificial nail composition, and curing failure may occur.

[Other ingredients]
The photocurable artificial nail composition of the present invention contains a radically polymerizable phosphoric acid compound having an acrylate group, (meth)acrylate, as long as it does not adversely affect the viscosity, applicability, handleability, durability of the cured coating film, and the like. In addition to the radically polymerizable compound having a group and not having a phosphorus atom and the photopolymerization initiator, various components can be blended. Such components include, for example, colorants, polyfunctional thiol compounds, polyol compounds, fragrances, silicone-based and fluorine-based antifoaming agents, silane coupling agents such as γ-glycidoxypropyltrimethoxysilane, Photopolymerization accelerators such as class amines, chain transfer agents, fillers, surface tension modifiers, polymerization inhibitors, flame retardants, antioxidants, ion adsorbents, stress reducing agents, preservatives, antibacterial agents, flexibility At least one selected from the group consisting of various additives such as imparting agents, waxes, halogen trapping agents, leveling agents, and wettability improvers.

The coloring agent includes one or more selected from the group consisting of pigments, luster materials, and dyes, and is used in an arbitrary amount to impart a desired color tone to the photocurable artificial nail composition. In particular, it is one or more selected from the group consisting of inorganic pigments, glittering materials, organic pigments and dyes used in nail coating materials, and does not significantly inhibit curing by ultraviolet irradiation (light irradiation).
The photocurable artificial nail composition before curing may contain not only pigments but also resin particles, decorative materials that can be blended in known photocurable artificial nail compositions, and the like.

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, and 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 202-(2), Yellow 203, Yellow 204, Yellow 205, Yellow 4, Yellow 401, Yellow 402, Yellow 403-(1), Yellow 404, Yellow 405, Yellow 406 , Orange No. 201, Orange No. 203, 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 105-(1), Red No. 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 230-(2), Red 231, Red 232, Red 3, Red 401, Red 405, Red 501, Red 502, Red 503, Red 504, Red 505, Red No. 506, titanium oxide, iron oxide, chromium oxide, manganese violet, carbon black, metal powder, metal flakes, metal oxide flakes, glass flakes and the like.

A polyfunctional thiol compound is blended as a curability modifier, a cross-linking agent and a viscosity modifier of a photocurable artificial nail composition. In addition, by blending the polyfunctional thiol compound into the photocurable artificial nail composition, it is possible to improve the wiping property when removing the cured coating film by wiping.
Examples of polyfunctional thiol compounds include those obtained by reacting hydroxyl groups of polyol compounds such as trimethylolpropane, pentaerythritol, and dipentaerythritol with thiol groups or compounds having groups that become thiol groups upon reaction. be done. For example, trimethylolpropane tris(3-mercaptopropionate), tris[(3-mercaptopropionyloxy)-ethyl]-isocyanurate, pentaerythritol tetrakis(3-mercaptobutyrate), pentaerythritol tetrakis(3-mercaptopropionate) pionate), dipentaerythritol hexakis (3-mercaptopropionate) and the like.
When the polyfunctional thiol compound is contained in the photocurable artificial nail composition, it can be contained in an amount of preferably 1.0 to 10.0% by mass.

The polyol compound functions as a diluent and adhesion improver for the photocurable artificial nail composition. Examples of polyol compounds include one or more selected from the group consisting of alkyl polyols, polyester polyols, polyether polyols, acrylic polyols, polybutadiene polyols, phenolic polyols, and the like. Among them, alkyl polyols, polyester polyols and polyether polyols are preferred.
The alkyl polyol is 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. One or more types can be mentioned.

Polyester polyols include one or more selected from the group consisting of condensation-type polyester polyols, addition-polymerized polyester polyols, polycarbonate polyols, and the like. Condensed polyester polyols include 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 diol compounds selected from the group consisting of adipic acid, isophthalic acid, terephthalic acid, sebacic acid, etc. It is obtained by a condensation reaction with an organic polybasic acid, and preferably has a weight average molecular weight of 100 or more and 100,000 or less. Examples of the addition-polymerized polyester polyol include polycaprolactone, and the weight average molecular weight is preferably 100 or more and 100,000 or less. Polycarbonate polyol is synthesized by direct phosgenation of polyol, transesterification using diphenyl carbonate, etc., and preferably has a weight average molecular weight of 100 or more and 100,000 or less.
Polyether polyols include, for example, polyether polyols obtained by opening polymerization of alkylene oxide.

Examples of the polymerization inhibitor include one or more selected from the group consisting of quinone compounds, salicylic acid hydrazides, tocopherol compounds, and the like.
When the polymerization inhibitor is contained in the photocurable artificial nail composition, it is, for example, 500 ppm or more, preferably 1,000 ppm or more, and preferably 5,000 ppm or less, based on the total photocurable artificial nail composition. can be blended so as to be 4,500 ppm or less.

[Usage, physical properties, etc. of photocurable artificial nail composition]
The cured coating film of the photocurable artificial nail composition of the present invention has excellent adhesion to the substrate, maintains the adhesion to the substrate for a long period of time, and has appropriate hardness.
The photocurable artificial nail composition of the present invention is a composition for coating the surface of the nail, like a so-called general manicure or pedicure. It may be coated on a surface provided with irregularities such as by pressing. In particular, it can be suitably used as a gel nail, for example, it can be used as a base coat layer that is directly applied to the user's nail, a color coat that is applied on top of the base coat layer, and a top coat layer that is applied thereon. can.
When used as a color coat, it can be used in a variety of colors such as solid color, lame tone, metallic luster tone, dark color and bright color by using a coloring agent.
When forming a cured coating film of the photocurable artificial nail composition of the present invention, the same facilities as those for conventional radically polymerizable nail polish cured by ultraviolet rays or the like, or general UV curing facilities are used. be able to.
When the photocurable artificial nail composition of the present invention is used in any layer, the cured coating film does not chip or peel off for a long period of time (for example, at least 2 weeks after curing), and the underlying layer or the user's nail does not adhere. On the other hand, it is possible to suppress the occurrence of floating.

The photocurable artificial nail composition of the present invention only needs to have a viscosity that allows it to be sufficiently applied with an applicator such as a brush.
The photocurable artificial nail composition preferably has a stress (maximum stress) of 15.0 MPa or more, more preferably 18.0 MPa or more, and 20.0 MPa or more when the cured coating film is broken by a tensile test. is more preferred. If it is less than 15.0 MPa, there is a possibility that it may become easy to peel off due to rubbing.
Further, the strain rate at break of the cured coating film is preferably 95.0% or more, more preferably 97.0% or more, and even more preferably 100.0% or more.

[Coating of nails with photocurable artificial nail composition]
The nails to be coated with the photocurable composition of the present invention may be either human fingernails or toenails, or animal nails such as dogs and cats.
When the photocurable artificial nail composition of the present invention is applied to coat the nail or the (un)cured coating film provided on the nail, the coated surface may or may not be sanded. . The method of applying the photocurable artificial nail composition is not particularly limited, and for example, an applicator such as a brush or an application method such as inkjet can be used.
The photocurable artificial nail composition of the present invention can be used as any of a base coat layer (gel base; foundation layer), an intermediate layer (color layer), or a top coat layer in gel nails. In particular, it is suitable for use as a base coat layer (gel base; underlying layer) because of its excellent adhesion to substrates.
After applying the photocurable artificial nail composition of the present invention, it is also possible to attach small ornaments, powder, etc. to the coating film surface of the photocurable artificial nail composition before curing to enhance the design.

Alternatively, a layer having a shape such as a nail is formed on one side of the sheet using the uncured photocurable artificial nail composition of the present invention, and after this layer is brought into contact with (transferred to) the surface of the nail, the sheet is formed. It can also be cured by irradiating with ultraviolet rays, with or without peeling.
According to the method of forming a layer on the sheet surface in advance using a photocurable artificial nail composition and transferring the layer, the surface of the nail can be coated with a uniform and accurate pattern without using an applicator such as a brush. Therefore, there is no need to clean the applicator after use.

Curing of the photocurable artificial nail composition after application can also be performed using a known UV curing apparatus. Although the irradiation energy required for curing differs depending on the composition of the photocurable artificial nail composition, the irradiation energy (accumulated light amount) due to light irradiation is 5 mJ/cm ² or more and 1000 mJ/cm ² or less, preferably 10 mJ/cm ² . 800 mJ/cm ² or more. If the irradiation energy is within this range, nail art having sufficient adhesion and abrasion resistance can be obtained.
As the light source, for example, a known ultraviolet light source such as a mercury lamp, a metal halide lamp, an ultraviolet light emitting diode (UV-LED), and an ultraviolet laser diode (UV-LD) can be used.
Among them, ultraviolet light emitting diodes (UV-LED) and ultraviolet laser diodes (UV-LD) are preferable from the viewpoints of small size, long life, high efficiency and low cost.

EXAMPLES The present invention will be described in more detail with reference to Examples below, but the present invention is not limited to these Examples. Unless otherwise specified, "%" means "% by mass" and "parts" means parts by mass.

<Examples 1 to 9, Comparative Examples 1 to 5>
The components shown in Table 1 were put into a container so that the ratio (mass parts) shown in Table 1 was obtained, and the mixture was heated to 50° C. and stirred with a dissolver while stirring. After stirring, the mixture was allowed to stand at 80° C. for 2 hours to remove air bubbles, thereby obtaining a photocurable artificial nail composition. All these steps were performed under light shielding.

The components in Table 1 are as follows.
PA: mixture containing 2-acryloyloxyethyl phosphate and bis(2-acryloyloxyethyl) phosphate PU: polycarbonate polyurethane methacrylate obtained from hydroxyethyl methacrylate, isophorone diisocyanate and polycarbonate diol IBXA: isobornyl acrylate HEMA: hydroxyethyl Methacrylate TPO: 2,4,6-trimethylbenzoyldiphenylphosphine oxide HPK: 1-hydroxycyclohexylphenyl ketone PM1: bismethacryloyloxyethyl phosphate PM2: methacryloyloxyethyl caproate phosphate

<Peel off load>
Adhesion of the resulting photocurable artificial nail composition was evaluated based on the peel-off load.
The peel-off load was measured by a 90° peel-off test as follows. The results are also shown in Table 1.
(90° peel-off test)
After wiping the surface of the nylon plate with ethanol to remove stains, a photocurable artificial nail composition was applied so that the film thickness after curing was 100 μm. It was cured with a 30 W-LED light for 30 seconds to form a cured coating film having a length of 10 mm and a width of 50 mm.
The width direction end of the cured coating film is pinched with a clip provided on a digital force gauge (Imada, ZTA-100N), and the cured coating film is peeled from the nylon plate at 100 mm / sec in the width direction at a peeling angle of 90 °. , peel-off load (maximum load (kg) required to peel off the cured coating film) was measured.

<Peel-off load increase/decrease rate>
The peel-off load increase/decrease rate was obtained by the following formula using the peel-off load of Example 1 as a reference. The results are also shown in Table 1.
Peel-off load change rate (%) = (peel-off load) / (peel-off load of Example 1) x 100

<Clouding test>
The photocurable artificial nail compositions of Examples 1 to 9 and Comparative Example 1 were applied to the nails of subjects and cured to form base coat layers (gel bases) for gel nails. Thereafter, a transparent color gel was applied and cured to form a transparent color layer, and a transparent top coat gel was applied and dried to form a transparent top coat layer to produce a gel nail. The curing condition was irradiation with a 30 W-LED light for 30 seconds.
Four weeks after the formation of the gel nail, the state of the gel nail was visually checked to confirm the presence or absence of cloudiness. As for the evaluation, A was evaluated when no cloudiness occurred after 4 weeks, and B was evaluated when cloudy after 4 weeks. Table 2 shows the results.

From Table 1, the photocurable artificial nail compositions of Examples 1 to 9 containing the "radically polymerizable phosphate compound having an acrylate group" did not contain the "radically polymerizable phosphate compound having an acrylate group". Compared to the photocurable artificial nail compositions of Examples 1 to 5, the peel-off load and peel-off load change rate, which are indicators of the adhesion of the cured coating film to the substrate (adhesive force to the nail), are large. It can be seen that the adhesion and adhesive strength of the film to the base material (nail) are high.
Further, there were no problems in terms of curability and appearance of the cured coating film, and it was suitable for use as a gel nail. Furthermore, from Table 2, the content of the "radical polymerizable phosphoric acid compound having an acrylate group" is more than 0% by mass (preferably 0.01% by mass) relative to the total amount of the constituent components of the photocurable artificial nail composition. Above) By making it 4.4% by mass or less (preferably 4.3% by mass or less), it is possible to form a base coat layer that is prevented from becoming cloudy over time while maintaining high adhesiveness to nails. I understand. This is extremely useful, especially when the color layer is made transparent, because the gel nail does not become cloudy over time and thus loses its beauty.

On the other hand, the photocurable artificial nail composition of Comparative Example 1 which does not contain a radically polymerizable phosphoric acid compound having an acrylate group, and a radically polymerizable phosphoric acid compound having a methacrylate group instead of the radically polymerizable phosphoric acid compound having an acrylate group. All of the photocurable artificial nail compositions of Comparative Examples 2 to 5 containing It was lower than 9 and had a problem in terms of adhesion, and was not satisfactory when used as a gel nail.

Claims (5)

(a) a radically polymerizable phosphoric acid compound having an acrylate group;
(b) a radically polymerizable compound having a (meth)acrylate group and no phosphorus atom;
(c) a photoinitiator,
A photocurable artificial nail composition comprising: 2. The photocurable artificial nail composition according to claim 1, wherein (a) the radically polymerizable phosphoric acid compound having an acrylate group is a radically polymerizable phosphoric acid ester compound having an acrylate group. 3. The photocurable artificial product according to claim 1, wherein (a) the radically polymerizable phosphoric acid compound having an acrylate group is 2-acryloyloxyethyl phosphate and/or bis(2-acryloyloxyethyl) phosphate. nail composition. (B) The radically polymerizable compound having a (meth)acrylate group and no phosphorus atom is a radically polymerizable oligomer having a (meth)acrylate group, the light according to any one of claims 1 to 3. A curable artificial nail composition. (a) The content of the radically polymerizable phosphoric acid compound having an acrylate group is more than 0% by mass and 4.4% by mass or less with respect to the total amount of the constituent components of the photocurable artificial nail composition. 5. The photocurable artificial nail composition according to any one of 4.