JPS60203628A - Photo-polymerizable composition - Google Patents

Abstract

PURPOSE:To obtain the titled composition curable with light in a short time, absorbing ultraviolet radiation in high efficiency to enable the saving of irradiation energy, and storable for a long period except for the exposure to short wavelength light, by compounding a cationic polymerizable compound with a novel photo-polymerization catalyst. CONSTITUTION:The objective composition can be produced by compounding (A) a cationic polymerizable compound (preferably epoxy compound) with (B) a salt composed of the positive group consisting of a hetero-cyclic compound containing (thio)pyrilium ring or pyridium ring and the negative group consisting of BF<->, SbF6<-> or AsF6<-> (e.g. N,N'-dimethyl-4,4'-dipyridium-bistetrafluoroborate, etc.). The amount of the component B is preferably 0.5-8pts.wt. per 100pts.wt. of the component A.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a photopolymerizable composition, and more particularly, a photopolymerizable composition that photocures in a particularly short time when it contains a novel photopolymerization catalyst. Regarding.

[Technical background of the invention and its problems]

Various cationic polymerizable compounds, especially epoxy resins, have excellent adhesive strength, adhesion, chemical resistance, and electrical properties such as electrical insulation, so they are used as coating materials,
It is widely used in fields such as electrical insulation materials, various laminated materials, and adhesives.

Currently, most of the epoxy resins used in these application fields are thermosetting, so they cannot be effectively applied to products that do not require heat treatment or to products that undergo continuous processing. There's a problem.

In recent years, in order to solve this problem, a special salt is added to epoxy resin as a photocatalyst, and the salt is irradiated with light in the visible to ultraviolet range (usually around 365 nm wavelength) to activate the salt as a cationic polymerization initiator. A method of photo-curing epoxy resin by converting it into acid has been adopted.

Such photocatalysts include, for example, siazonium salt type, aromatic iodonium salt type, aromatic sulfonium salt type,
Aromatic ammonium salt types, pyridium salt types, thiopyrylium salt types, and biryllium salt types are known. In all of these photocatalysts, when exposed to light, the salt decomposes, and as a result, the negative group moiety becomes, for example, HBF6. HBF4
It becomes a strong acid such as and polymerizes epoxy resin (monomer).

However, in these methods, there is a problem in that the curing speed of the resin is slow despite the fact that the photocatalyst is K, which generates the above-mentioned strong acid.

This is presumably due to the fact that in the above-mentioned wavelength range, light absorption by the positive group portion of the photocatalyst does not proceed sufficiently, and the rate of decomposition of the positive group portion after absorbing light is slow.

For example, Table 1 shows the light absorption characteristics of typical photocatalysts used conventionally.

Table 1 The value in parentheses represents 'Ogε (ε: molecular extinction coefficient).

As is clear from Table 1, the maximum absorption wavelength of conventional photocatalysts is within the irradiation wavelength range of commonly used ultraviolet lamps (365 nm).
It is located on the short wavelength side. Therefore, the light absorption effect is not sufficient.

For this reason, methods for shifting the absorption wavelength to longer wavelengths by adding various substituents to these catalysts, or using light that can shift the absorption wavelength of these catalysts to a specific range, have been proposed. Although methods such as adding a sensitizer have been attempted, none of these methods utilizes the irradiated light energy to decompose the positive group portion of the photocatalyst itself.

[Purpose of the invention]

An object of the present invention is to provide a photopolymerizable composition that contains a novel photocatalyst and is cured by short-term light irradiation.

[Summary of the invention]

The photopolymerizable composition of the present invention comprises a cationically polymerizable compound;
A positive group of a heterocyclic compound containing two conjugated pyridium rings, a thiopyrylium ring or a pyridium ring, and BF4
+ PF6-* 5bF6-* One type of negative group selected from the group AsF6- as an essential component.

In the composition of the present invention, first, the cationic polymerizable compound is the matrix. Examples of the cationically polymerizable compound include epoxy compounds; vinyl organic monomers, vinyl organic low polymers, cyclic organic ethers, cyclic organic esters, cyclic organic sulfides, cyclic amines, and cyclic organosilicon compounds.

Each of these may be used alone, or two or more may be used in an appropriate mixture.

Among these cationically polymerizable compounds, epoxy compounds are preferred. The epoxy compound may be any commonly known epoxy resin and is not particularly limited. For example, bisphenol A type epoxy resin; bisphenol F type epoxy resin: phenol black type I-oxy resin; alicyclic I-oxy resin;
Heterocyclic-containing I-oxy resins such as triglycyl isocyanate and hydantoin epoxy; hydrogenated bisphenol A
Type 21? Xylate resin: aliphatic epoxy resin such as propylene glycol-diglycidyl ether and pentaerythritol-polyglycidyl ether; engineered Ixy resin obtained by reaction of aromatic, aliphatic or alicyclic carbic acid with epichlorohydrin; Spiro ring-containing epoxy resin; glycidyl ether type epoxy resin which is the reaction product of an ortho-allyl-phenol novolak compound and epichlorohydrin; reaction between a diallyl bisphenol compound having an allyl group at the ortho position of each hydroxyl group of bisphenol A and epichlorohydrin Any product such as glycidyl ether type epoxy resin may be used.

The photocatalyst blended into the composition of the present invention includes two conjugated pyrylium rings, a thiogyrylium term, or a positive group of a heterocyclic compound containing a pyrylium ring, and BP;

It is a salt consisting of one type of negative group selected from the group of PF7 + 5bF6-*, AsF;

To specifically illustrate, the following formula: (wherein, Xa-t Xb-+ Xi + Xtre
X411- *X" is each By; e PF, -
, sbp, "*represents any one of the negative groups of AsF5-). In other words, N,N'-dimethyl-
4,4'-Nogirizomobistetrafluoro? rate, N,N'-dimethyl-4,4'-dipyridium-bishexafluorophosphate), N,N'-dimethyl-4
,4'-dipyridium-pishexafluoroantimonate, N,N'-dimethyl-4,4'-dipyridium bishexafluoroarsenate: N,N'-dimethyl-2,2',6 .6'-tetraphenyl-4,4'-bispirino-bistetrafluorodeley), N, N'
-dimethyl-2,2',6,6'-tetraphenyl-4
, 4'-bispyridium-bishexafluorophosphate, NtN'-dimethyl-2,2', 6,6'-tetraphenyl-4,4'-pispyridium bishexafluoroantimonate, N,N'- dimethyl-2,2'
, 6.6'-tetraphenyl-4,4'-bispyridium-4,4'-hexafluoroarsenate: 2.2
',6,6'-tetra7enyl-4,4'-zovirylium-bistetrafluoro? Rate, 2, 2', 6,
6'-tetraphenyl-4,4'-dihyrylium-bishexafluorophos 7ate, 2.2',6.6'-tetraphenyl-414'-cubyrylium-bishexafluoroantimo 4-t , 2,2',6,6'-tetraphenyl-4,4'-zopyrylium-bishexafluoroarsenate: 2,2',6,6'-tetraphenyl-4,4'-digylyl Violene-bistetrafluoroderate, 2.2',6.6'-tetraphenyl-4
, 41-dityrylviolene bishexafluorophosphate, S2. '2', 6.6'-tetraphenyl-
4,4'-zovirylviolene-bishexafluoroantimonate, 2.2',6.6'-tetraphenyl-4
, 4'-dipyrylpiolene bishexafluoroarsenate; 2t2't6. e'-tetraphenyl-4,4
′-dithiobyrylium-bistetrafluoro? rate,
212', L6'-tetraphenyl-4,4'-dithiobyrylium-bishexafluorophosphate), 2.
2',6.6'-Tetraphenyl-4,41-dithiobyrylium-bishexafluoroantimonate, 2.2
', 6.6 futetraphenyl-4,4'-dithiobyrylium-bishexafluoroarsenate: 2.2'
, 6,6'-tetraphenyl-4,4'-dithiobilylviolene-bistetrafluoro? rate, 2, '2'
, 6.6'-tetraphenyl-4,4'-dithiobilylviolene-bishexafluorophosphate, 2.2
', 6.6'-tetraphenyl-4,4'-dithiopyrylbiolene-bishexafluoroantimonate, 2.
2',6,6'-tetraphenyl-4,41-dithiobilylviolene-bishexafluoroarsenate and the like. These salts may be used alone or in an appropriate mixture of two or more.

Among these compounds, for example, the light absorption properties of salts whose negative group is BF4- are as shown in Table 2.

Table 2 As is clear from Table 2, the maximum absorption wavelength of the salt according to the present invention is located on the long wavelength side compared to the conventional salt (exemplified in Table 1), and the irradiation wavelength of the ultraviolet lamp is approaching the area. Therefore, this photocatalyst can efficiently absorb the light emitted from the lamp.

The acid generation mechanism of this photocatalyst is different from that of conventional photocatalysts, which generate acid by photodecomposition of the positive group moiety, without changing the skeletal structure of the positive group moiety. It is thought that strong acid is generated through hyperglycemia.

The photocatalyst according to the present invention is blended in an amount of 0.5 to 8 parts by weight based on 100 parts by weight of the cationic polymerizable compound that is the matrix. If it is less than 0.5 parts by weight, the effect as a photocatalyst will not be exhibited effectively, and if it exceeds 8 parts by weight, the corrosiveness of the composition will increase, the conductivity will increase, and the overall cost will increase in the first place. Therefore, it is not desirable.

The composition of the present invention has the above two components as essential components, but the following additives may be added as necessary.

Silica, alumina, calcium carbonate to eliminate distortion,
Inorganic fillers such as talc, mica, asbestos, and glass chips; leveling agents such as higher alcohols, alkylphenol phosphate ester salts, fluorine-containing surfactants, and higher amine fatty acid salts to improve wettability; adhesive properties Coupling agents such as silane coupling agents and phosphoric acid-based coupling agents to increase the oxidation properties; dyes such as titanium dioxide, cadmium red medium, and National 7 Earth Stretch.

The composition of the present invention can be easily prepared by blending the above-mentioned components in a conventional manner. In addition, it can be stored for a long time at room temperature as long as it is not exposed to short wavelength light.

[Embodiments of the invention]

Examples 1 to 17 The cationic polymerizable compounds were: A: epoxy resin based on bisphenol A glycysol ether (manufactured by Shell, trade name: EP828), B: alicyclic epoxy resin (manufactured by Daicel, trade name: ROXIDE) 2021) was prepared.

Various resin compositions were prepared by blending the photocatalysts shown in Table 3 in the ratios shown in 100 parts by weight of these.

Each composition was applied to a thickness of 10 to 30 μm on an aluminum plate,
The sample was passed through a light irradiation device equipped with three 30W/LM ultraviolet lamps. The pencil hardness of the photocured coating was examined.

At this time, the irradiation time required until the hardness of the coating film reached H was measured, and the results are summarized in Table 3.

Table 3 [Effects of the Invention] The photocurable composition of the present invention has a very high curing speed (short curing time) in photocuring using a normal ultraviolet lamp. Since it efficiently absorbs ultraviolet rays, it contributes to saving irradiation energy.

The composition of the present invention can be used to protect and decorate the surface of base materials such as metal, paper, wood, glass, and plastic.
It is also useful as an adhesive for bonding products that do not require heat treatment in a short period of time. Furthermore, it can be applied to the curing of printing inks, the production of laminates, and printing plates.

Claims (1)

[Claims]] A cationic polymerizable compound, a positive group of a heterocyclic compound containing two conjugated pyrylium rings, thiopyrylium rings, or pyridium rings, and BF4''
-, PF6- * 5bF6- + one type of negative group selected from the group of AsF6-. 2. A cationic polymerizable compound, a positive group of a heterocyclic compound containing two conjugated biryllium rings, thiopyrylium rings, or pyridium rings, and BF4-
+ PF6- + 5bF6- + one type of negative group selected from the group of AsF6- as an essential component, and further containing various additives as required, according to claim 1. Photopolymerizable composition. 3. The photopolymerizable composition according to claim 1 or 2, wherein the cationic polymerizable compound is an epoxy compound. 4. The salt has the following formula: (wherein, Xa t Xb * Xc-t Xd-r
e-I Xf- are respectively BF, -+ PF6- +
3. The photopolymerizable composition according to claim 1 or 2, which is a salt represented by: