JP2000212234A - Photocurable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a photocurable composition which can be perfectly cured to a deep inside even when it contains a pigment having high hiding power, a coloring dye, or an insufficiently light-transmitting material by mixing an ethylenically unsaturated compound with a specified cationic colorant, and a quaternary boron salt compound. SOLUTION: This composition is prepared by mixing 100 pts.wt. ethylenically unsaturated compound containing 5-95 wt.% urethane (meth)acrylate oligomer obtained by reacting a polyisocyanate having at least three isocyanate groups in the molecule with a hydroxyl-containing (meth)acrylic ester with 0.001-5 pts.wt. cationic colorant represented by the formula: D+.A1 and having a maximum absorption wavelength in the wavelength region of 400-1,200 nm and 0.005-10 pts.wt. quaternary boron salt compound represented by the formula. In the formulae, D+ is a cation having a maximum absorption wavelength in the wavelength region of 400-1,200 nm; A1 is an arbitrary anion; R1 to R4 are each an alkyl, an aryl, an aralkyl, an alkenyl, an alkynyl, silyl, or a heterocyclic group; and Z+ is an arbitrary cation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocurable composition, and more particularly, to a composition containing a pigment and a coloring dye having a high masking property, and containing a material having a large thickness and a poor light transmittance. The present invention also relates to a photocurable composition capable of completely curing the inside of the composition.

[0002]

2. Description of the Related Art In recent years, photo-radical polymerization and photo-cation polymerization have attracted attention from the viewpoints of quick drying, room temperature curability, the possibility of solventlessness, and energy saving, and are used for making printed circuit boards, resists or photomasks, paints for woodwork, It is used in various applications such as optical fiber coating, hard coating on plastic, and can coating.

At present, the mainstream of photocuring is 200 to 400 nm.
Irradiation of ultraviolet light is a UV curing in which the polymerizable monomer is rapidly cured, but ultraviolet light of 400 nm or less has poor permeability to the substance, and the surface of the composition containing the coloring pigment or the coloring dye at a high concentration is There is a problem that the resin is cured but the inside is not sufficiently cured. Further, even in a transparent system not containing a pigment, a coloring dye, or the like, in the case of a curing system containing a material having a poor ultraviolet light transmittance or an increase in the thickness of the curing system, the inside of the curing system is not sufficiently cured. Had problems.

To solve this problem, Japanese Patent Publication No. Sho 63-4
No. 0799 discloses an acylphosphine oxide-based initiator, and JP-A-6-298818 discloses a bisacylphosphine oxide-based initiator. These initiators include not only ultraviolet light of 400 nm or less, but also 40
The composition can be decomposed by visible light of 0 to 450 nm to generate radicals, and a composition containing a material having poor ultraviolet light transmission can provide a relatively large cured thickness, but is not yet satisfactory. There is also a disadvantage that the cured thickness varies greatly depending on the hue of the color pigment contained in the composition.

Further, JP-A-6-75374 and JP-A-10-81838 disclose photoradical polymerization initiation comprising a near-infrared light absorbing cationic dye or a visible light absorbing cationic dye and an organic boron salt-based sensitizer. Attempts have been made to increase the internal curability of the photocurable composition containing the color pigment by adding an agent. However, with this composition, although a sufficient cured thickness is obtained, the absolute amount of radicals involved in polymerization is small because most of the radicals generated from the organic boron salt sensitizer are consumed in the decolorization reaction of the cationic dye. However, there was a disadvantage that the degree of cure of the cured product was insufficient.

JP-A-10-195119 discloses (a) a compound capable of addition polymerization having at least one ethylenic double bond and having a urethane skeleton in the molecule, (b1) a dye cation and (B2) A photopolymerizable composition containing a boron anion represented by a specific general formula is disclosed. JP-A-3-111402 discloses a near-infrared light polymerization initiator comprising a dye cation and a boron anion.
No. 619 discloses a near-infrared light polymerization initiator comprising a dye cation compound and a boron anion compound. Urethane acrylates containing these near-infrared light polymerization initiators (double bond and urethane bond in the molecule) ), But none of them was sufficient in terms of cured thickness, degree of curing, and the like.

[0007]

DISCLOSURE OF THE INVENTION The present invention relates to a curable composition which contains a colorant having a concealing property such as a coloring pigment or a coloring dye, or contains a material having a low ultraviolet light transmittance, and which has conventionally been difficult to cure by light. In the system, a photocurable composition capable of sufficiently curing the inside of the composition, a coating material, an adhesive, an adhesive,
An object of the present invention is to provide a photocurable composition that can be preferably used in the fields of ink, hologram material, and the like.

[0008]

Means for Solving the Problems In order to solve this problem, the present inventors used a cationic dye having a maximum absorption wavelength in the wavelength region of 400 to 1200 nm and a quaternary boron salt compound as a sensitizer. As a result of intensive studies on the photocurable composition to be used, even when the composition contains a color pigment having a concealing property, a coloring dye or the like by using a specific urethane (meth) acrylate oligomer as a radical polymerizable component. The inventors have found that a photocurable composition having a sufficient cured thickness and degree of cure is obtained, and have completed the present invention.

That is, the present invention provides: 1) (A) a compound having an ethylenically unsaturated group
Parts by weight, (B) 400 to 120 represented by the general formula (1)
Cationic dyes 0.001-5 parts by formula having a maximum absorption wavelength in a wavelength region of ^{0nm (1); D + ·} A 1 - ( in D ⁺ the formula cation having a maximum absorption wavelength in a wavelength region 400~1200nm And A ₁ ^- represents an arbitrary anion.) And (C) 0.005 to 10 parts by weight of a quaternary boron salt compound represented by the general formula (2)

Embedded image (Wherein R _1, R _2, R ₃ and R ₄ are each independently an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an alkynyl group, a silyl group, a heterocyclic group, or a halogen atom, Z ⁺ is 5 to 95% by weight of the compound having an ethylenically unsaturated group in the photocurable composition containing any cation.) A photocurable composition, which is a urethane (meth) acrylate oligomer obtained by reacting an isocyanate with a hydroxyl group-containing (meth) acrylate;

2) The photocurable composition as described in 1) above, wherein 3 to 40% by weight of the compound having an ethylenically unsaturated group is an N-vinylamide compound. ,

3) In the photocurable composition according to 2) above, the N-vinylamide compound is selected from the group consisting of N-vinylformamide, N-vinylacetamide and / or N-methyl-N-vinylacetamide. 1
A photocurable composition that is a compound of at least one species,

4) In the photocurable composition described in 1) to 3) above, the cation (D ⁺ ) having an absorption in the wavelength region of 400 to 1200 nm is polymethine, xanthene, acridine, azine, oxazine, thiazine, diaryl. A photocurable composition, which is one or more compounds selected from the group consisting of methane and triarylmethane compounds;

5) The photocurable composition according to 4) above, wherein the polymethine compound is a compound represented by the general formula (3):

Embedded image (In the formula, R ₅ , R ₆ , R ₇ , R ₈ and R ₉ each independently represent a hydrogen atom, an alkyl group, an aryl group or a halogen atom.)

6) In the photocurable composition described in 1) to 5) above, 0.1 to 10% by weight of an ultraviolet radical polymerization initiator which generates a radical by absorbing light having a wavelength of 200 to 400 nm. Photocurable composition characterized by containing

7) In the photocurable composition described in 1) to 6) above, the polyisocyanate having three or more isocyanate groups in one molecule is an isocyanurate of diisocyanate, a burette of diisocyanate, or a polyol and diisocyanate. A photocurable composition, which is one or more compounds selected from the group consisting of adducts of

8) The photocurable composition according to 7) above, wherein the diisocyanate is at least one compound selected from the group consisting of aliphatic diisocyanates and alicyclic diisocyanates. Composition,

9) The photocurable composition according to 1) to 6) above, wherein the polyisocyanate having three or more isocyanate groups in one molecule is a monomeric triisocyanate. Composition.

[0018]

Embodiments of the present invention will be described below in detail. The photocurable composition of the present invention, by irradiating light having a wavelength that matches the absorption wavelength of the cationic dye,
Even if the composition contains a color pigment or a coloring dye having a masking property, the composition can be sufficiently cured in the thickness direction and a photocured product having an excellent degree of curing can be obtained. The photocurable composition of the present invention further comprises an ultraviolet light radical polymerization initiator that generates radicals by absorbing light of 200 to 400 nm, and irradiates ultraviolet light of 400 nm or less to form a cationic dye / 4. The curing of the surface of the composition in air, which is difficult with a graded boron salt compound-based photopolymerization initiator, becomes possible. In the present invention, "(meth) acryl" means both "methacryl" and "acryl".

The urethane (meth) acrylate oligomer obtained by reacting a polyisocyanate having three or more isocyanate groups in one molecule with a hydroxyl group-containing (meth) acrylate used in the present invention has an extremely high photocuring rate. Cationic dyes with fast generated radical amount /
Even when a photo-radical polymerization initiator composed of a quaternary boron salt-based compound is used, a sufficient degree of curing can be obtained.

Examples of the polyisocyanate having three or more isocyanate groups in one molecule used in the present invention include an isocyanurate of diisocyanate, a burette of diisocyanate and / or an adduct of diisocyanate to a polyol.

The isocyanurate of diisocyanate refers to a diisocyanate compound which is converted to a cyclic trimerization catalyst such as N, N ', N "-tris (dimethylaminoalkyl).
Tertiary amines such as hexahydrotriazine, 2,4,6-tris (dimethylaminomethyl) phenol, triethylamine and diazabicyclooctane; and potassium acetate, 2-ethylhexane lead, sodium benzoate, potassium naphthenate and the like. It is a compound obtained by performing a trimerization reaction in the presence of a carboxylate, a tertiary alkyl phosphine such as tributyl phosphine, an alkali metal salt of an imide such as phthalimide potassium, and the structure is exemplified by the general formula (4). Is done.

Embedded image (Wherein D ₁ , D ₂ and D ₃ each independently have no group that reacts with an isocyanate group,
It is an organic group obtained by removing an individual isocyanate group. )

The burette of diisocyanate is represented by 1
It is a reaction product of 3 moles of water molecules and 3 moles of diisocyanate, and its structure is exemplified by the general formula (5).

Embedded image (Wherein D ₄ , D ₅ and D ₆ each independently have no group that reacts with an isocyanate group,
It is an organic group obtained by removing an individual isocyanate group. )

The adduct of diisocyanate to a polyol includes triols such as trimethylolpropane and glycerin and tetraols such as pentaerythritol.
The reaction is carried out at a CO / OH equivalent ratio of 2/1 or more, and the structure is represented by the general formula (6) when the polyol is a triol and by the general formula (7) when the polyol is a tetraol. Is shown.

Embedded image (In the formula, D ₇ , D ₈ and D ₉ each independently have no group which reacts with an isocyanate group.
E ₁ is a trivalent organic group having 3 to 10 carbon atoms obtained by excluding the hydroxyl group of triol. )

[0024]

Embedded image (No groups reactive with an isocyanate group, respectively in D _10, D _11, D ₁₂ and D ₁₃ is the formula independently is an organic group obtained by eliminating the two isocyanate groups from a diisocyanate, E ₂ Is a tetravalent organic group having 3 to 10 carbon atoms obtained by removing a hydroxyl group of tetraol.)

Specific examples of the diisocyanate used as a raw material of the polyisocyanate having three or more isocyanate groups in one molecule include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, and 1,3-xylylene diisocyanate. Isocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate, 1,5-naphthalene diisocyanate, tolidine diisocyanate, tetramethyl xylene diisocyanate, etc., ethylene glycol, diethylene glycol,
Propylene glycol, dipropylene glycol, 1,
An adduct is obtained by reacting a low molecular weight diol such as 3-butanediol with the diisocyanate in an excess amount.

However, in the present invention, aliphatic diisocyanates such as hexamethylene diisocyanate and lysine diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, dicyclohexylmethane-2,4'-diisocyanate, ω,
An alicyclic diisocyanate such as ω'-diisocyanate dimethylcyclohexane, and an adduct obtained by reacting the above-mentioned aliphatic or alicyclic diisocyanate with the low-molecular-weight diol in an excessively equal amount can reduce the urethane (meth) acrylate oligomer used in the present invention to a low viscosity. To improve workability. Further, the urethane (meth) in the present invention
As the polyisocyanate used as a raw material of the acrylate oligomer, a monomeric triisocyanate can also be used. Specific examples of the monomeric triisocyanate include aromatic monomeric triisocyanates such as triphenylmethane triisocyanate and tris (isocyanatephenyl) thiophosphate. In the present invention, lysine ester triisocyanate is used. , 1,
6,11-undecane triisocyanate, 1,3,6
-Triisocyanates of aliphatic monomers such as hexamethylene triisocyanate, 1,8-diisocyanate-4-isocyanatomethyloctane and triisocyanates of alicyclic monomers such as bicycloheptane triisocyanate are urethane (meta- ) It is preferable because the viscosity of the acrylate oligomer is reduced to improve the workability.

Specific examples of the hydroxyl group-containing (meth) acrylate used in the present invention include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate.
Acrylate, 4-hydroxybutyl (meth) acrylate, 4-hydroxycyclohexyl (meth) acrylate, 2-hydroxy-3-phenyloxypropyl (meth) acrylate, 3-chloro-2-hydroxybutyl (meth) acrylate, polyethylene glycol mono (Meth) acrylate, polypropylene glycol mono (meth) acrylate, caprolactone-modified hydroxyethyl (meth) acrylate, glycerin mono (meth) acrylate, glycerin di (meth) acrylate, glycerin acrylate methacrylate, pentaerythritol tri (meth) acrylate, anhydrous phthalate Mono (meth) acrylic acid ester of diol consisting of condensate of acid and ethylene glycol, condensate of phthalic anhydride and propylene glycol Mono become diol (meth)
Acrylic esters and the like are exemplified. In the present invention, a compound having an acryloyl group having a particularly high photocuring rate is preferred.

When synthesizing the urethane (meth) acrylate oligomer in the photocurable composition of the present invention, 1
Polyisocyanates having three or more isocyanate groups in the molecule and hydroxyl-containing (meth) acrylates are
The reaction is preferably carried out at a CO / OH equivalent ratio of 1.0 / 0.9 to 1.0 / 10, more preferably 1.0 / 0.95 to 1.0 / 5.0. When the NCO / OH equivalent ratio exceeds 1.0 / 0.9, the storage stability becomes poor due to the remaining isocyanate groups.
Since the content of the remaining hydroxyl group-containing (meth) acrylic acid ester is too large, the photocurability may be reduced, and neither is preferable.

The synthesis reaction of the urethane (meth) acrylate oligomer is usually at 20 to 100 ° C., preferably at 40 to 8 ° C.
Perform at a temperature of 0 ° C. If the temperature is too high, the (meth) acryloyl group may be undesirably polymerized. Although a solvent may or may not be used, when a solvent is used, a solvent inert to an isocyanate group, for example, a ketone solvent such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, and an acetate solvent such as ethyl acetate and butyl acetate are used. ,
Aromatic solvents such as toluene and xylene, and (meth) acrylate monomers having no active hydrogen can be used, and they may be used alone or as a mixture.
At the time of the reaction, a catalyst may be added, and examples thereof include known urethane bond forming catalysts such as tertiary amines (triethylamine, triethylenediamine, etc.) and organic tin compounds (dibutyltin dilaurate, tin octylate, etc.).

The photocurable composition of the present invention preferably contains an N-vinylamide compound in order to further increase the photocuring rate on the surface of the composition and inside the composition. An N-vinylamide compound refers to a compound in which a vinyl group is directly bonded to a nitrogen atom. N-vinylamide compounds are
Since the polymerization rate with the (meth) acryloyl group is high and at the same time the polymerization inhibition by oxygen, which is peculiar to radical polymerization by ethylenically unsaturated bonds, is relatively unlikely to occur, the photocuring rate is significantly improved. It is a suitable compound for the photocurable composition of the present invention. Specific examples of the N-vinylamide compound include N-vinylpyrrolidone,
N-vinylcaprolactam, N-vinylformamide,
N-methyl-N-vinylformamide, N-vinylacetamide, N-methyl-N-vinylacetamide, etc., among which N-vinylformamide, N-vinylacetamide, N-methyl-N-vinylacetamide are safe It is particularly suitable for the photocurable composition of the present invention because it gives a photocured product having a high appearance and a high appearance.

The photocurable composition of the present invention comprises a urethane (meth) acrylate oligomer formed from a polyisocyanate having three or more isocyanate groups in one molecule and a hydroxyl group-containing (meth) acrylate, N-vinylamide In addition to the system compound, a monomer or oligomer having an ethylenically unsaturated group may be blended.

The monomer having an ethylenically unsaturated group is
When the number of unsaturated groups in the molecule is one, a monofunctional monomer,
Two or more cases are classified as polyfunctional monomers. In the present invention, the monofunctional monomer is blended mainly for the purpose of lowering the viscosity of the composition and improving coatability and workability. On the other hand, the polyfunctional monomer, like the monofunctional monomer, is blended mainly for the purpose of improving the workability by lowering the viscosity of the composition and improving the curability. The oligomer is a compound generally having two or more ethylenically unsaturated groups in one molecule and controlling various properties such as strength, elongation, and abrasion resistance of a cured coating film obtained by radical polymerization.

Specific examples of the monofunctional monomer used in the present invention include n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, lauryl (meth) acrylate, Butoxyethyl (meth) acrylate, cyclohexyl (meth) acrylate, 4-
tert-butylcyclohexyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dicyclopentenyl (meth) acrylate, isobornyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxydi Propylene glycol (meth) acrylate, phenoxyethyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, phenoxydiethylene glycol (meth) acrylate, N-acryloylmorpholine, tetrahydrofurfuryl (meth) acrylate, and the like; -Hydroxyethyl (meth) acrylate, 2-
Hydroxyl-containing monomers such as hydroxypropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth)
Amino group-containing monomers such as acrylamide, and monomers having acidic groups such as (meth) acrylic acid, 2- (meth) acryloyloxyethyl succinic acid, 2- (meth) acryloyloxyethyl phthalic acid and 2-acryloyloxyethyl acid phosphate And monomers containing a hydrolyzable silyl group such as γ-methacryloxypropyltrimethoxysilane and vinyltriethoxysilane.

Specific examples of the polyfunctional monomer include diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, and 1,3-butane. Diol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth)
Acrylate, trimethylolpropane tri (meth) acrylate, ethylene oxide-modified trimethylolpropane triacrylate, propylene oxide-modified trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, etc. Functional monomers are exemplified, and more specifically, “Applications and Markets of UV / EB Curing Technology”, p12-14, p20-31 (1
989 (published by CMC).

Specific examples of the oligomer having an ethylenically unsaturated group which can be used in the present invention include epoxy (meth) acrylate, polyester (meth) acrylate, polybutadiene (meth) acrylate, silicone (meth) acrylate, Examples thereof include unsaturated polyester resins. Also, urethane (meth) acrylate synthesized from diisocyanate / diol / hydroxyl group-containing (meth) acrylate can be used in the same manner.

In the photocurable composition of the present invention, the urethane (meth) acrylate oligomer synthesized from the polyisocyanate having three or more isocyanate groups and the hydroxyl group-containing (meth) acrylate has an ethylenically unsaturated group. 5 to 95% by weight of the compound, preferably 1
The object of the present invention can be achieved by containing 0 to 80% by weight. If it is less than 5% by weight, sufficient photocurability cannot be obtained, and if it exceeds 95% by weight, the viscosity of the composition becomes too high and coating becomes extremely difficult.

In the photocurable composition of the present invention, the N-vinylamide compound is preferably 3 to 40% by weight, more preferably 5 to 40% by weight of the compound having an ethylenically unsaturated group.
The object of the present invention can be achieved by including the content of about 30% by weight. If the amount is less than 3% by weight, the effect of the N-vinylamide compound will not be sufficiently exhibited, and if it exceeds 40% by weight, the concentration of the monofunctional monomer will increase, so that the photocuring speed may decrease, which is not preferable.

Next, the photopolymerization initiator component in the photocurable composition of the present invention will be described. When the cationic dye of the general formula (1) and the quaternary boron salt compound of the general formula (2) constituting the present invention are combined, 400 to 1200 nm is obtained.
Is decomposed by the light having the wavelength of, and the polymerization is started at the same time when the color of the cationic dye is erased. If the quaternary boron salt-based compound is not present, the decolorization reaction of the cationic dye does not proceed sufficiently or the polymerization reaction is difficult to occur. The decolorization reaction of completely proceeds, and the polymerization initiation reaction proceeds. Further, by adding a polymerization accelerator, the polymerization initiation reaction proceeds more efficiently. Examples of these polymerization accelerators include compounds that receive an electron from a dye radical generated upon irradiation with light having a wavelength of 400 to 1200 nm to generate a radical, and significantly improve the internal curability of a cured product. Can be. Such polymerization accelerators include organic peroxides, diaryliodonium salts,
Triarylsulfonium salts, N-alkoxypyridinium salts, triazine compounds having a trihalomethyl group,
And halogenated sulfone compounds.

The cationic dye of the general formula (1) used in the present invention is a compound having a maximum absorption wavelength in a wavelength region of 400 to 1200 nm. The maximum absorption wavelength is determined by using a cationic dye as water, methanol, ethanol, toluene, xylene, acetone, methyl ethyl ketone, ethyl acetate, n-butyl acetate, N, N-dimethylformamide, N-methyl-2-pyrrolidone, chloroform, methylene chloride, A general spectrophotometer (for example, Uvest V-570 manufactured by JASCO Corporation) that can be dissolved in a general solvent such as acetonitrile and dimethyl sulfoxide to measure the absorption spectrum of the compound from the ultraviolet light region to the near infrared light region. And UV-3100 manufactured by Shimadzu Corporation. However, the method for measuring the maximum absorption wavelength is not limited to this method. Here, preferable examples of the cationic dye include, for example, polymethine, xanthene, triarylmethane, diarylmethane, acridine, azine, oxazine, and thiazine-based compounds.
As shown in Tables 1 to 3, polymethine and triarylmethane compounds are particularly excellent in polymerization initiation ability and decoloring ability and are suitable for the present invention. Among them, the general formula (3)
A polymethine compound having the structure is particularly excellent in those properties.

In the general formula (3), R ₅ , R ₆ , R ₇ , R ₈ and R ₉ each independently represent a hydrogen atom, an alkyl group, an aryl group or a halogen atom. The group may have a substituent, and specific examples of such a substituent include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, and tert. -Butyl group, n-octyl group, n-dodecyl group, cyclohexyl group, phenyl group, tolyl group, anisyl group, naphthyl group, benzyl group,
Phenethyl group, methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, sec-butoxy group, tert-butoxy group, phenoxy group, naphthoxy group, benzyloxy group, hydroxy group, cyano group and the like. Can be

[0041]

[Table 1]

[Table 2]

[Table 3]

The counter anion (A ₁ ⁻ ) of the above-mentioned general formula (1) is an arbitrary anion, for example, a halogen anion such as chlorine, bromine or iodine anion, a benzenesulfonic acid anion, a p-toluenesulfonic acid anion, Sulfonic acid anions such as methanesulfonic acid anion and naphthalenesulfonic acid anion, tetraphenyl borate, tetraanisyl borate, n-butyl triphenyl borate, n-butyl tri (4-tert-butylphenyl) borate, tetrabenzyl borate, tetrafluoro Borate anions such as borate, ClO ₄ ⁻ , P
Various anions such as F ₆ ⁻ and SbF ₆ ⁻ are exemplified. However, the invention is not limited to these examples. These cationic dyes may be used in any ratio as required.
More than one species may be used.

The quaternary boron compound represented by the general formula (2) in the photocurable composition of the present invention comprises a quaternary organic boron anion and any cation (Z ⁺ ). In the general formula (2), R ₁ , R ₂ , R ₃ and R ₄ each independently represent an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an alkynyl group, a silyl group, a heterocyclic group or a halogen atom; Z ⁺ represents an arbitrary cation,
Here, in R ₁ , R ₂ , R ₃ and R ₄ of the general formula (2),
The alkyl group, aryl group, aralkyl group, alkenyl group, alkynyl group, silyl group, and heterocyclic group may have any substituent. Specific examples of such substituents include
Methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, isobutyl group,
tert-butyl group, n-octyl group, n-dodecyl group, cyclopentyl group, cyclohexyl group, phenyl group, tolyl group, xylyl group, anisyl group, biphenyl group, naphthyl group, benzyl group, phenethyl group, diphenylmethyl group, methoxy Group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, sec-butoxy group, tert-butoxy group, methylenedioxy group,
Ethylenedioxy group, phenoxy group, naphthoxy group, benzyloxy group, methylthio group, phenylthio group, 2-furyl group, 2-thienyl group, 2-pyridyl group, fluoro group, and the like. It is not limited.

Specific examples of the quaternary organoboron anion in the general formula (2) include n-butyltriphenylborate, n-octyltriphenylborate, n-dodecyltriphenylborate, sec-butyltriphenylborate, and tert. -Butyl triphenyl borate,
Benzyltriphenylborate, n-butyltri (p-
(Anisyl) borate, n-octyl tri (p-anisyl) borate, n-dodecyl tri (p-anisyl) borate, n-butyl tri (p-tolyl) borate, n-butyl tri (o-tolyl) borate, n-butyl tri (4
-Tert-butylphenyl) borate, n-butyltri (4-fluoro-2-methylphenyl) borate, n
-Butyl tri (4-fluorophenyl) borate, n-
Butyl tri (1-naphthyl) borate, n-butyl tri [1- (4-methylnaphthyl)] borate, triphenylsilyl triphenyl borate, trimethyl silyl triphenyl borate, tetra-n-butyl borate, di-
Examples thereof include n-butyldiphenyl borate and tetrabenzyl borate. Compounds having a structure in which R ₁ is an alkyl group and R ₂ , R ₃ and R ₄ are an aryl group have a good balance between stability and curability. It is suitable for the photocurable composition of the invention.

Specific examples of Z ⁺ in the general formula (2) include tetramethylammonium, tetraethylammonium, tetra-n-butylammonium, tetraoctylammonium, N-methylquinolinium,
N-ethylquinolium, N-methylpyridinium, N-
Ethylpyridinium, tetramethylphosphonium, tetra-n-butylphosphonium, trimethylsulfonium, triphenylsulfonium, trimethylsulfoxonium, diphenyliodonium, di (4-tert-
(Butylphenyl) iodonium, lithium cation, sodium cation and the like. These quaternary organic boron anions and optional cations Z ⁺ can be used in the present invention in any combination. The present invention is not limited to these examples. Further, two or more quaternary organic boron salt compounds may be used in combination.

Next, specific examples of the polymerization accelerator which can be used in the present invention are shown below. The diaryliodonium salt is composed of a diaryliodonium cation and an optional anion (A
₂ ^-) from the constructed. Specific examples of the diaryliodonium cation include diphenyliodonium, p-anisylphenyliodonium, di (4-tert-butylphenyl) iodonium, di (o-tolyl) iodonium, di (3-nitrophenyl) iodonium and the like. .

The triarylsulfonium salt is composed of a triarylsulfonium cation and an optional anion (A ₃ ⁻ ). Specific examples of the triarylsulfonium cation include triphenylsulfonium, diphenyl (p-anisyl) sulfonium, diphenyl (o-tolyl) sulfonium, diphenyl (4-fluorophenyl) sulfonium, diphenyl [4- (phenylthio)
Phenyl] sulfonium, diphenyl [4- (diphenylsulfoniumyl) phenyl] sulfonium and the like.

The N-alkoxypyridinium salt comprises an N-alkoxypyridinium cation and an optional anion (A ₄ ⁻ )
It is composed of Specific examples of the N-alkoxypyridinium cation include N-ethoxypyridinium, N-ethoxy-2-picolinium, N-ethoxy-3-picolinium, N-ethoxy-4-picolium, N-ethoxy-4-phenylpyridinium, Ethoxy-4-cyanopyridinium, N, N'-diethoxy-4,4'-bipyridinium and the like can be mentioned.

[0049] _{^{A 2 -, A 3 -,}} A 4 - Examples of, BF
_{^{4 -, PF 6 -, AsF}} 6 -, SbF 6 -, ClO 4 -, Cl -,
Br ^-, tetraphenylborate, tetrakis (pentafluorophenyl) borate, benzene sulfonic acid anion, p- toluenesulfonate anion, trifluoromethanesulfonic acid anion, and the like. Any of these anions, diaryliodonium cations, triphenylsulfonium cations, and N-alkoxypyridinium cations can be used in the present invention.

Specific examples of the triazine compound having a trichloromethyl group include 2,4,6-tris (trichloromethyl) -s-triazine, 2,4,6-tris (tribromomethyl) -s-triazine, , 4-bis (dichloromethyl) -6-trichloromethyl-s-triazine, 2- (4-chlorophenyl) -4,6-bis (trichloromethyl) -s-triazine, 2,4-bis (4-
Methoxyphenyl) -6-trichloromethyl-s-triazine, 2,4-bis (3-chlorophenyl) -6-trichloromethyl-s-triazine, 2- (4-methoxystyryl) -4,6-bis (trichloromethyl ) -S-
Triazine, 2- (4-chlorostyryl) -4,6-bis (trichloromethyl) -s-triazine and the like.

Specific examples of the halogenated sulfone compound include trichloromethylphenylsulfone, tribromomethylphenylsulfone, trichloromethyl-4-chlorophenylsulfone, 2,4-dichlorophenyltrichloromethylsulfone, and 2-methyl-4-chlorophenyltrichloromethylsulfone. , 2,4-dichlorophenyltribromomethylsulfone and the like.

Specific examples of the organic peroxide include benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, tert-butylperoxybenzoate, di (tert-butylperoxy) isophthalate, and di (tert-butylperoxy). ) Terephthalate, di (tert-butylperoxy) phthalate, 2,5-
Dimethyl-2,5-di (benzoylperoxy) hexane, 3,3 ′, 4,4′-tetra (tert-butylperoxycarbonyl) benzophenone and the like are exemplified.
These polymerization accelerators may be used as a mixture of two or more.

The ultraviolet radical polymerization initiator used in the present invention is used for curing the surface layer of a coating film in the air. These ultraviolet light radical polymerization initiators have a wavelength of 400 nm.
The following ordinary photopolymerization initiators of the type that are excited by irradiation with ultraviolet light to generate radicals are used. Examples of such a compound include a compound represented by the general formula (8).

Embedded image (In the formula, Ar represents an aryl group, and X represents an alkyl group, an alicyclic group, a benzyl group, an alkoxycarbonyl group, a benzoyl group, an aryl group, or a phosphinoyl group having a substituent.)

Here, in Ar of the general formula (8), the aryl group may have an arbitrary substituent, and specific examples of such a substituent include a methyl group, an ethyl group, an n-propyl group, Isopropyl group, n-butyl group, sec-butyl group, isobutyl group, tert-butyl group, n-octyl group, n-dodecyl group, cyclohexyl group, phenyl group,
Tolyl, anisyl, naphthyl, benzyl, phenethyl, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec-butoxy, tert-butoxy, 2-hydroxyethoxy , Phenoxy group, naphthoxy group, benzyloxy group,
Hydroxy group, acetoxy group, benzoyloxy group, acryloyloxy group, methacryloyloxy group, carboxyl group, methoxycarbonyl group, ethoxycarbonyl group, benzoyl group, naphthoyl group, acetyl group, propionyl group, dimethylamino group, diethylamino group, morpholino group, Examples include a methylthio group, a phenylthio group, a 2-furfuryl group, a 2-thienyl group, a 2-pyridyl group, a 2-quinolinyl group, a fluoro group, a chloro group, and a bromo group, but the present invention is limited to these examples. Never.

In X of the general formula (8), an alkyl group, an alicyclic group, a benzyl group, an alkoxycarbonyl group, a benzoyl group, and an aryl group may have a substituent. Represents a methyl group, an ethyl group, n
-Propyl group, isopropyl group, n-butyl group, sec
-Butyl group, isobutyl group, tert-butyl group, n-
Octyl, n-dodecyl, cyclohexyl, phenyl, tolyl, anisyl, naphthyl, benzyl, phenethyl, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, sec
-Butoxy group, tert-butoxy group, phenoxy group,
Naphthoxy group, benzyloxy group, hydroxy group, acetoxy group, benzoyloxy group, carboxyl group, methoxycarbonyl group, ethoxycarbonyl group, benzoyl group,
Naphthoyl group, acetyl group, propionyl group, dimethylamino group, diethylamino group, morpholino group, methylthio group, phenylthio group, 2-furfuryl group, 2-thienyl group, 2-pyridyl group, 2-quinolinyl group, fluoro group, chloro group , A bromo group and the like, but the present invention is not limited to these examples.

In X of the general formula (8), specific examples of the substituent of the substituted phosphinoyl group include methyl, ethyl, n-propyl, isopropyl, n
-Butyl group, sec-butyl group, isobutyl group, ter
t-butyl group, 2-ethylhexyl group, n-octyl group, 2,4,4-trimethylpentyl group, cyclohexyl group, phenyl group, tolyl group, 2,5-dimethylphenyl group, mesityl group, cumenyl group, benzyl group Phenethyl group, benzoyl group, 2,6-dichlorobenzoyl group,
2,4,6-trimethylbenzoyl group, 2,6-dimethoxybenzoyl group, 2,6-diethoxybenzoyl group,
Examples include a naphthoyl group, but the present invention is not limited to these examples.

Specific examples of the compound represented by the general formula (8) include benzoin-based compounds such as benzoin isobutyl ether, benzoin isopropyl ether, benzoin ethyl ether and benzyl dimethyl ketal, diethoxyacetophenone, 2-hydroxy-2-methyl- 1-
Phenylpropan-1-one, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropane-1
-One, 1-hydroxycyclohexylphenyl ketone, 4-tert-butyl-trichloroacetophenone, 2-methyl-1- [4- (methylthio) phenyl]
-2-morpholinopropanone-1, 2-benzyl-2-
Acetophenone compounds such as dimethylamino-1- (4-morpholinophenyl) -butanone-1, glyoxyester compounds such as methylphenylglyoxylate,
Benzophenone-based compounds such as benzophenone, methyl benzoylbenzoate, hydroxybenzophenone, 4-phenylbenzophenone, and acrylated benzophenone;
Acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide; bis (2,6-dimethoxybenzoyl) -2,4;
4-trimethylpentylphosphine oxide, bis (2,6-dichlorobenzoyl) -phenylphosphine oxide, bis (2,6-dichlorobenzoyl)-
Bisacylphosphine oxide compounds such as 2,5-dimethylphenylphosphine oxide and bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide are exemplified.

In addition, ultraviolet radical polymerization initiators having a structure other than the general formula (8), for example, thioxanthone compounds such as 2,4-diethylthioxanthone and 2-isopropylthioxanthone can also be used. Compounds called P1 type photoinitiators, such as P2 type photoinitiators, such as P2 type photoinitiators, such as glyoxyester type compounds, acylphosphine oxide type compounds and bisacylphosphine oxide type compounds, can be used alone. Compound,
An ultraviolet radical polymerization initiator such as a thioxanthone-based compound is generally used in combination with a hydrogen-donating compound. P1
When the type photoinitiator is used together with the hydrogen donor, the curability is improved.

The hydrogen-donating compound means a compound capable of donating hydrogen to an initiator excited by light, for example, an aliphatic amine such as triethanolamine or methyldiethanolamine, 2-dimethylaminoethylbenzoic acid,
Examples include aromatic amines such as ethyl dimethylaminobenzoate, isobutyl 4-dimethylaminobenzoate, and 4,4-dimethylaminobenzophenone.

These ultraviolet light radical polymerization initiators can be used alone or in combination of two or more.

The addition amounts of these photopolymerization initiators are as follows. The cationic dye represented by the general formula (1) is
The object of the present invention can be achieved by using 0.001 to 5 parts by weight, preferably 0.01 to 2 parts by weight, per 100 parts by weight of the compound having an ethylenically unsaturated group. If the amount is less than 0.001 part by weight, polymerization is not sufficiently performed,
Insufficient curing may occur. If the amount exceeds 5 parts by weight, the cured product is colored and the hue is impaired, and it is economically disadvantageous.

The quaternary boron salt compound represented by the general formula (2) is a compound 1 having an ethylenically unsaturated group.
The object of the present invention can be achieved by using 0.005 to 10 parts by weight, preferably 0.05 to 5 parts by weight with respect to 00 parts by weight. If the amount is less than 0.005 parts by weight, polymerization may not be sufficiently performed and curing may be insufficiently completed, and at the same time, the decolorization reaction of the cationic dye does not sufficiently proceed and the cured product is colored. If the amount exceeds 10 parts by weight, the physical properties of the cured product are reduced.

When the polymerization accelerator is used in an amount of 0.005 to 10 parts by weight, preferably 0.01 to 5 parts by weight, per 100 parts by weight of the compound having an ethylenically unsaturated group, the curing accelerating ability becomes apparent. If the amount is less than 0.005 parts by weight, the effect of the polymerization accelerator will not be sufficiently exhibited, and if it exceeds 10 parts by weight, the physical properties of the cured product may be reduced or the stability of the composition of the present invention may be significantly impaired. Is not preferred.

The ultraviolet radical polymerization initiator is generally used in an amount of 0.1 to 100 parts by weight of the compound having an ethylenically unsaturated group.
It is used in an amount of 1 to 10 parts by weight, preferably 0.5 to 5 parts by weight. If the amount is less than 0.1 part by weight, curing in the air may be insufficient. If the amount exceeds 10 parts by weight, the physical properties of the cured product deteriorate, the cured product is deteriorated by the residual ultraviolet radical polymerization initiator, and Any change is not preferred.

In some cases, the photocurable composition of the present invention may cause a color return of the cationic dye after photocuring.
In that case, a compound having a substituent at at least one of the ortho positions of the carbon atom bonded to the phenolic hydroxyl group, an aromatic thiol-based compound, an amine-based compound, and a phosphorus-based compound can be used as a cationic dye. Color return can be suppressed.

Specific examples of the compound having a substituent at at least one of the ortho positions of the carbon atom bonded to the phenolic hydroxyl group include 2,4,6-tri-tert-butylphenol and 2,6-di-tert-butylphenol. -P-cresol, N, N-hexamethylenebis (3,5-di-te
rt-butyl-4-hydroxy-hydrocinnamide),
Octadecyl-3- (3,5-di-tert-butyl-
4-hydroxyphenyl) propionate, 3,5-di-tert-butyl-4-hydroxy-benzylphosphonate-diethyl ester, 1,3,5-trimethyl-
2,4,6-tris (3,5-di-tert-butyl-
4-hydroxybenzyl) benzene, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 4,4′-thiobis (3-methyl-6-tert)
-Butylphenol), 2,4,6-tris (dimethylaminomethyl) phenol, isooctyl-3- (3,
5-di-tert-butyl-4-hydroxyphenyl)
Propionate, 2- (3,5-di-tert-butyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5-di-tert-amyl-2-hydroxyphenyl) benzotriazole, 2- (3,5
-Di-tert-butyl-2-hydroxyphenyl) benzotriazole, 2,4-di-tert-butylphenyl-3,5-di-tert-butyl-4-hydroxybenzoate, p-tert-butylphenyl salicylate, p -Octylphenyl salicylate, 2-hydroxy-4-octyloxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone and the like. For further details, see “12695 Chemical Products” (published in 1995 by Kagaku Kogyo Nippo), p969 to p973, p97
7-p981 and "Development of Polymer Additives and Latest Technology" (CMC Co., Ltd., published in 1992)
Compounds described in pages 37 to 56, Polyfile (published by Taiseisha), 1997, Vol. 3 Phenol compounds described on pages 22 to 30 can be used.

Specific examples of the aromatic thiol compound include thiophenol, 2-mercaptobenzothiazole,
-Mercaptobenzoxazole, 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, 2,4,6-trimercapto-s-triazine,
2-mercaptoimidazoline and the like are exemplified.

Examples of the amine compound include aliphatic amines such as triethanolamine and tributylamine, and aromatic amines such as N, N-dimethylaniline and N, N-dimethyl-p-toluidine. , 2,6,6
-Tetramethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, 2- (3,5-di-tert-butyl-4-hydroxybenzyl) -2 Bis (1,2,2,6,6-pentamethyl-4-piperidyl) -n-butylmalonate, 4-benzoyloxy-2,2,6,6-tetramethylpiperidine, 8-acetyl-3-dodecyl-
Hindered amine compounds such as 7,7,9,9-tetramethyl-1,3,8-trisazaspiro [4,5] decane-2,4-dione are particularly preferred. For more information, see "12695 Chemical Products" (Kagaku Kogyo Nippo, 1995
Compounds described in p982 to p984) are exemplified.

Specific examples of the phosphorus compound include triphenyl phosphine, trimethyl phosphite, triethyl phosphite, tributyl phosphite, tridecyl phosphite, triphenyl phosphite, and tris (2,4
-Di-tert-butylphenyl) phosphite, tris (nonylphenyl) phosphite, diphenylisodecylphosphite, phenyldiisodecylphosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octylphosphite Etc., but more specifically, “Development of polymer additives and the latest technology”
(CMC Corporation published in 1992) p60-6
The compounds described in 6, etc. can be used.

The compound for suppressing the color reversion of these cationic dyes is generally added in an amount of 0.05 to 15 parts by weight, preferably 0.2 to 10 parts by weight, based on 100 parts by weight of the compound having an ethylenically unsaturated group. This can achieve the purpose of suppressing color return. If the amount is less than 0.05 part by weight, it is difficult to completely suppress the color return. If the amount exceeds 15 parts by weight, the curability may be reduced, or the physical properties of the cured product may be deteriorated.

In the photocurable composition of the present invention, one or more kinds of coloring materials selected from coloring pigments, coloring dyes and glittering pigments can be used. Examples of coloring pigments include white pigments such as titanium white and zinc white, black pigments such as carbon black and titanium black, and known organic and inorganic pigments described in “Saishin Pigment Handbook” (edited by Japan Pigment Technical Association, published in 1976). Can be used. As a coloring dye, "Dye Handbook" (edited by The Society of Synthetic Organic Chemistry, published in 1970)
And the like can be used. As the glitter pigment, aluminum powder, aluminum paste, silver powder, mica coated with titanium oxide, mica-like iron oxide and the like can be used. These coloring agents can be added in an amount of 0 to 200 parts by weight based on 100 parts by weight of the compound having an ethylenically unsaturated bond.

Further, various extender pigments can be added to the photocurable composition of the present invention, such as silica, silica-alumina, alumina, aluminum hydroxide, quartz, glass, calcium carbonate, and the like. Examples include powders of kaolin, talc, mica, aluminum sulfate, calcium phosphate, and the like, and powders obtained by coating the surfaces of these powders with a polyfunctional (meth) acrylate monomer or a silane coupling agent. It does not matter if two or more different types of extenders are separately added or added after mixing.

An organic polymer compound can be added to the photocurable composition of the present invention for the purpose of suppressing curing shrinkage or imparting flexibility. As used herein, the term "organic polymer compound" refers to a homopolymer or copolymer of an organic monomer having a number average molecular weight of 1,000 or more. Examples of such an organic polymer compound include polystyrene resin, polyurethane resin, polyvinyl acetal resin, polyvinyl butyral resin, saturated polyester resin, novolak resin, phenol resin, epoxy resin, polyvinyl pyrrolidone, chlorinated polyolefin, butadiene rubber, styrene-butadiene. Rubber components such as rubber, nitrile rubber, and acrylic rubber, various thermoplastic elastomers such as polystyrene, polyolefin, polydiolefin, polyurethane, and polyester, polymethyl (meth) acrylate, polyethyl (meth) acrylate, and polybutyl (meth) A homopolymer or a copolymer of an alkyl (meth) acrylate such as acrylate is exemplified.

The photocurable composition of the present invention can be used as a solventless material and is expected to contribute to the improvement of the global environment. Of course, it can also be used in a form diluted with a conventional solvent. As the solvent used at that time, general solvents used for conventional applications such as paints, for example, aromatic hydrocarbons such as toluene and xylene, ethanol, 2-
Propanol, alcohols such as 1-butanol, acetone, methyl ethyl ketone, ketones such as methyl isobutyl ketone, diethylene glycol dimethyl ether,
Ethers such as triethylene glycol dimethyl ether, esters such as ethyl acetate, butyl acetate and amyl acetate, and monoethers of ethylene glycol such as methyl cellosolve and ethyl cellosolve can be used. These solvents can be used alone or in combination of two or more. Organic solvents generally reduce the viscosity of the composition,
It is used to improve workability, adhesion of the composition to a substrate, and the like.

For the purpose of preventing polymerization during storage, a thermal polymerization inhibitor can be added to the photocurable composition of the present invention. Specific examples of the thermal polymerization inhibitor that can be added to the photocurable composition of the present invention include p-methoxyphenol, hydroquinone, alkyl-substituted hydroquinone, catechol,
Tert-butylcatechol, phenothiazine and the like can be mentioned.

The photocurable composition of the present invention may further contain an antifoggant, an anti-fading agent, a fluorescent whitening agent, a surfactant, a plasticizer, a flame retardant, an antioxidant, an ultraviolet absorber, a foaming agent, depending on the purpose. An agent, a fungicide, an antistatic agent, a magnetic substance, a conductive material, or the like may be used.

Light sources suitable for curing the photocurable composition of the present invention include high-pressure mercury lamps, ultrahigh-pressure mercury lamps, metal halide lamps, short-arc metal halide lamps, xenon lamps, sodium lamps, halogen lamps, incandescent lamps, sunlight , A semiconductor laser, an excimer laser and the like.

The photocurable composition of the present invention can be used as a coating material for exterior or interior building materials, a coating material for inorganic materials such as concrete, a coating agent for plastics, an adhesive, a pressure-sensitive adhesive, a printing ink, a binder, and the like. It can be applied to a photosensitive material such as a hologram and a resist material by being applied on the top.

[0079]

The present invention will be described below with reference to examples. Of course, the present invention is not limited to the embodiments described below. [Urethane acrylate oligomer synthesis example 1] Thermometer,
Sumidur N3500 (isocyanurate of hexamethylene diisocyanate: trade name of Sumitomo Bayer Urethane Co., Ltd.) 388 g in a reaction vessel equipped with a stirrer, a dropping funnel, a cooling pipe, etc., as shown in Table 4, Blenmer AP-400 (polypropylene glycol) Monoacrylate: Nippon Oil & Fats Co., Ltd. (325 g), 2-hydroxyethyl acrylate 97 g, Aronix M-
305 (pentaerythritol triacrylate: pentaerythritol tetraacrylate = 6: 4 mixture
248 g of Toa Gosei Chemical Industry Co., Ltd. and 0.04 g of hydroquinone methyl ether were added, followed by 0.06 g of dibutyltin dilaurate, and the liquid temperature was 50 ° C.
The reaction vessel was immersed in a water bath and stirred for 4 hours so as not to exceed. Thereafter, the water bath was removed and dibutyltin dilaurate was added.
Then, the solution was kept at 60 ° C. using an oil bath and reacted for 4 hours until the infrared absorption of isocyanate disappeared. After completion of the reaction, the mixture was cooled to room temperature to obtain a urethane acrylate oligomer as a colorless and high-viscosity liquid having a solid content of 100% (UA-A).

[Urethane Acrylate Oligomer Synthesis Examples 2 to 11] As shown in Table 4, the types of the hydroxyl group-containing acrylate and polyisocyanate used in the above urethane acrylate oligomer synthesis example 1 or the reaction charge amounts were changed. By performing the same reaction as in Example 1, urethane acrylate oligomers (UA-B to K) were obtained.

[Urethane acrylate oligomer comparative synthesis example 1] As shown in Table 4, 224 g of hexamethylene diisocyanate, Blemmer AP-400 were placed in a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, a cooling pipe and the like.
650 g, 2-hydroxyethyl acrylate 155
g and hydroquinone methyl ether (0.04 g) were added, followed by dibutyltin dilaurate (0.06 g). The reaction vessel was immersed in a water bath and stirred for 4 hours so that the liquid temperature did not exceed 50 ° C. Thereafter, the water bath was removed, and 0.02 g of dibutyltin dilaurate was charged. The solution was kept at 60 ° C. using an oil bath, and reacted for 4 hours until the infrared absorption of isocyanate disappeared. After the reaction is completed, it is cooled to room temperature
A colorless, high-viscosity liquid urethane acrylate oligomer (comparative UA-A) having a solid content of 100% was obtained.

[Urethane acrylate oligomer comparative synthesis example 2] As shown in Table 4, 224 g of hexamethylene diisocyanate, FA2D (caprolactone-modified hydroxyethyl acrylate Daicel Chemical Co., Ltd.) were placed in a reaction vessel equipped with a thermometer, a stirrer, a dropping funnel, a cooling tube, and the like. 459 g, 2-hydroxyethyl acrylate 116 g, Aronix M-305167
g and hydroquinone methyl ether (0.04 g) were added, followed by dibutyltin dilaurate (0.06 g). The reaction vessel was immersed in a water bath and stirred for 4 hours so that the liquid temperature did not exceed 50 ° C. Thereafter, the water bath was removed, and 0.02 g of dibutyltin dilaurate was charged. The solution was kept at 60 ° C. using an oil bath, and reacted for 4 hours until the infrared absorption of isocyanate disappeared. After the reaction is completed, it is cooled to room temperature,
A colorless, high-viscosity liquid urethane acrylate oligomer (comparative UA-B) having a solid content of 100% was obtained.

[0083]

[Table 4]

[Preparation of White Paints] Various white paints (white paints 1 to 13) having the compositions shown in Tables 5 and 6 were prepared using the synthesized urethane acrylate oligomer, diluent monomer, titanium oxide, dispersant and defoamer. Comparative white paints 1 and 2) were prepared.

[0085]

[Table 5]

[Table 6]

[Preparation of Photopolymerization Initiator Solution] Cationic dye,
Quaternary boron salt compound, ultraviolet light radical polymerization initiator, N
Using -methyl-2-pyrrolidone, photopolymerization initiator solutions (PI-1 to 6) having the compositions shown in Table 7 were prepared.

[0087]

[Table 7]

[Photocurability Test] As shown in Tables 8 and 9, each white paint and each photopolymerization initiator solution were combined and a photocurability test was performed. -Curing method 1 As Examples 1 to 4 and Comparative Examples 1 and 2, the photocurable composition obtained by combining the white paint and the photopolymerization initiator liquid shown in Tables 8 and 9 was cured to a film thickness of about 150 µm. Bar coater # 30 on an aluminum plate (size 150 × 70 mm) with spacers of 200 μm thickness at both ends
Painted. Thereafter, a 30 μm-thick PET film is coated so that air does not enter the coating, and a metal halide lamp (Ushio Electric UVL-6000M2-N1) is coated.
Photocured at an input power of 120 W / cm). The metal halide lamp is incorporated in a belt conveyor type light irradiation device (USHIO Corporation UVC-5033), the distance between the metal halide lamp and the painted object is 25 cm, the belt conveyor speed is 4.2 m / min, and the number of light irradiations is 1 and 2 Met. The irradiation light amount at this time is 0.5 J / c when the number of irradiations is one, as measured with an integrating light meter UIT-102 (receiver UVD-365PD) manufactured by Ushio Inc.
m ² and the number of irradiation times was 1.0 J / cm ² .

Curing Method 2 As Examples 5 to 17 and Comparative Examples 3 to 6, a photocurable composition obtained by combining a white paint and a photopolymerization initiator solution shown in Tables 8 and 9 was applied to a film thickness of about 50. , 100, 150 μm on an aluminum substrate (150 × 70 mm) with an applicator, and cured with a metal halide lamp (USHIO Inc. UVL-6000M2-N1 input power 120 W / cm) in the same manner as curing method 1. Light cured in air. Light irradiation frequency is once (0.5 J / c
m ² ) and twice (1.0 J / cm ² ).

[Evaluation Method of Coating Film] Drying to the touch The cured coating films of Examples 1 to 17 and Comparative Examples 1 to 6 were peeled off from an aluminum plate, and were subjected to "JIS K-5400 (General paint test method). In accordance with the evaluation method in "5 Drying time", the cured state of the front and back surfaces of the coating film was evaluated by dryness to the touch. -MEK rubbing test The cured coating films of Examples 1 to 17 and Comparative Examples 1 to 6 were peeled off from an aluminum plate, and several drops of methyl ethyl ketone (MEK) were dropped on the front side and the back side of the cured coating, respectively. (Crecia brand name) 20 times. The change of the coating film after rubbing was visually evaluated.

[0091]

[Table 8]

[Table 9]

From Tables 8 and 9, it was found that the isocyanate group was 1
By using a urethane (meth) acrylate oligomer synthesized from a polyisocyanate having three or more molecules in the molecule and a hydroxyl group-containing (meth) acrylate, a composition having a high masking property becomes a cationic dye / quaternary boron salt-based compound. It has been clarified that a sufficient thickness can be completely photocured by using a photopolymerization initiator containing.

[0093]

According to the present invention, a urethane (meth) acrylate oligomer obtained by reacting a polyisocyanate having three or more isocyanate groups in one molecule with a hydroxyl group-containing (meth) acrylate ester, represented by the general formula (1): The photocurable composition containing the cationic dye of the formula (1) and the quaternary boron salt-based compound of the general formula (2) can obtain extremely high photocurability even when a pigment or a coloring dye having a high hiding property is contained. Therefore, the photocurable composition can be preferably used in the fields of paints, adhesives, pressure-sensitive adhesives, inks, hologram materials and the like.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification Symbol FI Theme Court ゛ (Reference) G03F 7/027 513 G03F 7/027 513 7/029 7/029 (72) Inventor Kazuhiko Oga Oita City, Oita Prefecture (2) Inventor Toshio Koshikawa 1-1-1 Ohnodai, Midori-ku, Chiba-shi, Chiba Pref. Showa Denko Co., Ltd.

Claims (9)

[Claims] (A) 100 parts by weight of a compound having an ethylenically unsaturated group (B) A cationic dye having a maximum absorption wavelength in a wavelength region of 400 to 1200 nm represented by the general formula (1) 0.0
D ⁺ · A ₁ ⁻ (D ⁺ is a cation having a maximum absorption wavelength in a wavelength region of 400 to 1200 nm, and A ₁ ⁻ represents an anion.) And (C) a quaternary boron salt compound represented by the general formula (2)
0.005 to 10 parts by weight (Wherein R _1, R _2, R ₃ and R ₄ are each independently an alkyl group, an aryl group, an aralkyl group, an alkenyl group, an alkynyl group, a silyl group, a heterocyclic group, or a halogen atom, Z ⁺ is 5 to 95% by weight of the compound having an ethylenically unsaturated group in the photocurable composition containing any cation.) A photocurable composition, which is a urethane (meth) acrylate oligomer obtained by reacting an isocyanate with a hydroxyl group-containing (meth) acrylate. 2. A compound having an ethylenically unsaturated group,
The photocurable composition according to claim 1, wherein 40% by weight is an N-vinylamide compound. 3. The method according to claim 1, wherein the N-vinylamide compound is N-vinylformamide, N-vinylacetamide and / or N-vinylacetamide.
The photocurable composition according to claim 2, which is one or more compounds selected from the group consisting of methyl-N-vinylacetamide. 4. A cation (D ⁺ ) having an absorption in a wavelength region of 400 to 1200 nm selected from the group consisting of polymethine, xanthene, acridine, azine, oxazine, thiazine, diarylmethane and triarylmethane compounds. The photocurable composition according to any one of claims 1 to 3, which is a compound described above. 5. The photocurable composition according to claim 4, wherein the polymethine compound is a compound represented by the general formula (3). Embedded image (In the formula, R ₅ , R ₆ , R ₇ , R ₈ and R ₉ each independently represent a hydrogen atom, an alkyl group, an aryl group or a halogen atom.) 6. An ultraviolet light radical polymerization initiator which generates a radical by absorbing light having a wavelength of 200 to 400 nm is contained in an amount of 0.1 to 10 parts by weight. The photocurable composition according to item 1. 7. The polyisocyanate having three or more isocyanate groups in one molecule is at least one compound selected from the group consisting of an isocyanurate of diisocyanate, a burette of diisocyanate and an adduct of diisocyanate to polyol. The photocurable composition according to any one of claims 1 to 6, wherein 8. The photocurable composition according to claim 7, wherein the diisocyanate is at least one compound selected from the group consisting of an aliphatic diisocyanate and an alicyclic diisocyanate. 9. The photocurable composition according to claim 1, wherein the polyisocyanate having three or more isocyanate groups in one molecule is a monomeric triisocyanate.