JPH05222111A - Curable composition containing benzothiazolium salt compound - Google Patents

Abstract

PURPOSE:To provide a curable composition containing a cationically polymerizable compound which cures at a low temp. within a short time upon light irradiation and/or heating. CONSTITUTION:The title composition comprises a cationically polymerizable compound, a benzothiazolium salt, and a compound (a) generating a free radical upon light irradiation or heating. This composition can be made to cure at a low temp. within a short time upon light irradiation and/or heating by suitably selecting the compound (a). It is suited for use as the material of a coating composition, adhesive, ink, etc., because it has excellent properties after curing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a curable composition, and more particularly to a cationically polymerizable composition which is cured by light irradiation and / or heat at a low temperature in a short time. A cured product of the composition has excellent physical properties and is therefore suitably used as a material for paints, adhesives, inks and the like.

[0002]

2. Description of the Related Art Examples of catalysts and compositions for curing cationically polymerizable compounds such as epoxy compounds by light irradiation are disclosed in JP-A-50-151997 and JP-A-50-1586.
No. 80, etc. A catalyst for curing a cationically polymerizable compound such as an epoxy compound by heating and a composition thereof are described in JP-A-56-1.
52833, JP-A-58-37003, JP-A-63-2
23002, JP-A-2-178319, and JP-A-3-178319
The 17119 issue is known. A catalyst for curing a cationically polymerizable compound such as an epoxy compound by light irradiation and heat and its composition are disclosed in JP-A-2-19681.
It is described in the 2nd report.

[0003]

A compound obtained by cationically polymerizing a cationically polymerizable compound such as an epoxy compound has a smaller cure shrinkage and a smaller curing shrinkage than a compound obtained by radically curing a radically polymerizable compound such as an acrylic compound. In this case, it has various characteristics such as not being affected by oxygen.
Cationic polymerization catalysts used for cationic curing include photocatalysts and thermal catalysts. For example, as a catalyst for curing a cationically polymerizable compound by light irradiation, there are sulfonium salt-based catalysts, iron-arene complexes and the like. Although these catalysts show high photoactivity, they cannot cure the cationically polymerizable composition by heating in the temperature range usually used. Therefore, there is a problem that the thick film cannot be cured even if the heat treatment is performed after the photo-curing. On the other hand, JP-A-58-
37003, JP-A-63-223002, JP-A-2-1.
Since the catalysts described in 78319 and JP-A-3-17119 are thermal catalysts, the cationically polymerizable compound cannot be cured by light irradiation, and in many cases the temperature at which polymerization is initiated is high. There's a problem. Further, the catalyst described in JP-A-2-196812, etc. is described to be able to cure a cationically polymerizable compound by heating and light irradiation, but in the case of photocuring, its catalytic activity is remarkably high. Low.

Therefore, a cationic polymerization catalyst having a high activity against both light and heat, and a curable composition containing the same have not been known so far. The present invention has been made in view of these circumstances, and provides a high-performance curable composition capable of curing a cationically polymerizable compound at low temperature and in a short time by light irradiation and / or heat. Has a purpose.

[0005]

Means for Solving the Problems The inventors of the present invention have made extensive studies to achieve the above-mentioned object, and in the case of photocuring,
By using a benzothiazolium salt compound in combination with a compound that generates an active radical upon irradiation with light, the benzothiazolium salt compound can act as a photocationic polymerization catalyst, and the cationically polymerizable compound can be photocured. I found that it would be possible. Further, in the case of heat curing, it was found that the decomposition temperature of the benzothiazolium salt compound occurs at a lower temperature by using a benzothiazolium salt compound and a compound which generates an active radical by heating, and the cationic polymerizable compound It has become possible to cure the resin at low temperature and in a short time by light and / or heat.

The present invention is a curable composition containing component (A): a cationically polymerizable compound, component (B): a benzothiazolium salt compound, and component (C): a compound which generates an active radical. is there.

The present invention will be described in detail below. Examples of the cationically polymerizable compound as the component (A) used in the present invention include the following compounds. (A) As a compound having an epoxy group, 1,1,3-
Tetradecadiene dioxide, limonene dioxide, 4-vinylcyclohexene dioxide, (3,4
-Epoxycyclohexyl) methyl-3,4-epoxycyclohexylcarboxylate, di (3,4-epoxycyclohexyl) adipate, phenylglycidyl ether, bisphenol A type epoxy resin, halogenated bisphenol A type epoxy resin, o-, m-, There are epoxy compounds such as p-cresol novolac type epoxy resin, phenol novolac type epoxy resin, and polyglycidyl ether of polyhydric alcohol.

(B) Styrene and α as vinyl compounds
-Styrenes such as methylstyrene and p-chloromethylstyrene; alkyl vinyl ethers such as n-butyl vinyl ether, isobutyl vinyl ether, cyclohexyl vinyl ether and hydroxybutyl vinyl ether;
Alkenyl vinyl ethers such as allyl vinyl ether and 1-octahydronaphthyl vinyl ether; alkynyl vinyl ethers such as ethynyl vinyl ether and 1-methyl-2-propenyl vinyl ether; aryl vinyl ethers such as phenyl vinyl ether and p-methoxyphenyl vinyl ether; butanediol divinyl ether , Alkyldivinyl ethers such as triethylene glycol vinyl ether and cyclohexanediol divinyl ether; aralkyl dialkyl ethers such as 1,4-benzenedimethanol divinyl ether, N-m-chlorophenyldiethanolamine divinyl ether and m-phenylene bis (ethylene glycol) divinyl ether. Vinyl ethers; hydroquinone divinyl ether, resorcinol divinyl ether Aryl divinyl ethers such as ether; N- vinylcarbazole, there is a cationic polymerizable nitrogen-containing compounds such as N- vinylpyrrolidone.

As the (C) bicycloorthoester compound, 1-phenyl-4-ethyl-2,6,7-trioxabicyclo [2,2,2] octane, 1-ethyl-4-
Hydroxymethyl-2,6,7-trioxabicyclo [2,2,2] octane etc. (d) As the spiro orthocarbonate compound, 1,
5,7,11-Tetraoxaspiro [5,5] undecane, 3,9-Dibenzyl-1,5,7,11-tetraoxaspiro [5,5] undecane and 1,4,6-trioxaspiro [4,4] nonane, 2-methyl-1,4
6-trioxaspiro [4,4] nonane, 1,4,6-
Examples thereof include spiro orthoester compounds such as trioxaspiro [4,5] decane. These may be used alone or in combination of two or more. Among (a) to (d), the compound having an epoxy group of (a) is preferably used.

Examples of the benzothiazolium salt compound as the component (B) used in the present invention include, for example, the following general formulas [1] to
The compound shown by [3] can be mentioned. That is, as a benzothiazolium salt compound [1],

[0011]

[Chemical 1] [Wherein R ₁ and R ₂ represent a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a nitro group, a vinyl group, a carbamoyl group or an alkanoyl group, and R ₃ represents a hydrogen atom, an alkyl group or a substituted group. Represents a good phenyl group,
R ₄ represents a hydrogen atom, a halogen atom, an alkyl group, an optionally substituted phenyl group or an alkylthio group, and R 4
₅ represents a hydrogen atom, a halogen atom, an alkyl group, or a phenyl group, and X represents SbF ₆ , AsF ₆ , PF ₆ or BF.
₄ ]] As a benzothiazolium salt compound [2]

[0012]

[Chemical 2] [In the formula, R ₆ represents a hydrogen atom, an alkyl group or a cyano group, R ₇ represents an alkyl group or an optionally substituted phenyl group, and R ₈ represents a hydrogen atom, an alkyl group, a halogen atom, or a substituted phenyl group. Optionally represents a phenyl group or an alkylthio group, R ₉ represents a hydrogen atom, an alkyl group, a halogen atom, an alkyl group or a phenyl group, and X represents S
bF ₆ , AsF ₆ , PF ₆ or BF ₄ ] As a benzothiazolium salt compound [3],

[0013]

[Chemical 3] [In the formula, R ₁₀ and R ₁₁ represent a hydrogen atom, a halogen atom, an alkyl group or an alkoxy group, and R ₁₂ represents a hydrogen atom, an alkyl group, a halogen atom, an optionally substituted phenyl group or an alkylthio group. R ₁₃ represents a hydrogen atom, an alkyl group, a halogen atom, an alkyl group or a phenyl group, and X represents SbF ₆ , AsF ₆ , PF ₆ or BF ₄ ].

Among the benzothiazolium salt compounds of the component (B) used in the present invention, the compound represented by the general formula [1] can be synthesized, for example, by the method described in JP-A-2-26813. ..

Among the benzothiazolium salt compounds of the component (B) used in the present invention, the compound represented by the general formula [2] or [3] can be obtained, for example, by the following method. Cinnamyl halide such as cinnamyl bromide and equimolar amount of benzazole or benzothiazole derivative are allowed to react at room temperature to 80 ° C for several hours to 30 days in the presence of a solvent such as methyl alcohol, acetone or acetonitrile, if necessary. Then, the obtained product can be obtained by ion exchange. Examples of the salt used for ion exchange include alkali metal or alkaline earth metal salts of SbF ₆ , AsF ₆ , PF ₆ or BF ₄ .

The compound which generates an active radical which is the component (C) of the present invention is a compound which generates an active radical upon heating or irradiation with light, and examples thereof include the following.

(A) Compound that generates active radicals by light irradiation As a compound that generates active radicals by light irradiation,
A generally known photo-radical initiator can be applied, and examples thereof include benzyl type, benzoin ether type, benzyl ketal type, benzophenone type and thioxanthone type. In addition, azo compounds such as azoisobutyronitrile, azide compounds, disulfide compounds, and peroxide compounds are applicable. Particularly, a ketone-based photo radical initiator is preferably applied. For example, benzophenone, benzoylbenzoic acid, methyl benzoylbenzoate, 4-benzoyl-4′-methyldiphenyl sulfide, 3,3′-dimethyl-4-methoxybenzophenone, tetra (t-butylperoxycarbonyl) benzophenone, 2-chloro. Thioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, anthraquinone, 2-ethylanthraquinone, 1,8-dichloroanthraquinone, 1,2-benzanthraquinone, 9-fluorenone. , Benzanthuron, 9,10-phenanthrenequinone xanthone and the like are used.

(B) Compound which generates active radical by heating As a compound which generates active radical by heating, generally known azo compounds such as azoisobutyronitrile, azide compounds, disulfide compounds and peroxides. A compound or the like is applied. In particular, peroxide compounds are preferably applied, and the following compounds are used, for example. Ketone peroxides such as methyl ethyl ketone peroxide, cyclohexanone peroxide, acetylacetone peroxide; 1,1-bis (t-butylperoxy) cyclohexanone, 2,2-
Peroxyketals such as bis (t-butylperoxy) butane; Hydroperoxides such as t-butyl hydroperoxide and cumene hydroperoxide; Dialkyls such as dicumylperoxide and di-t-butylperoxide Peroxide; Diacyl peroxide such as isobutyl peroxide, acetyl peroxide and benzoylperoxide; Peroxycarbonate such as diisopropylperoxycarbonate; Peroxy such as t-butylperoxyacetate and cumylperoxyneodecanate Esters; acetylcyclohexyl sulfonyl peroxide, tetra (t-butylperoxycarbonyl) benzophenone and the like can be applied. In particular, aromatic diacyl peroxide and peroxy ester are preferably used.

The mixing ratio of the component (A) cationically polymerizable compound and the component (B) benzothiazolium salt compound is
The amount of the benzothiazolium salt compound is 0.01 to 20 parts by weight, preferably 0.1 to 10 parts by weight, based on 100 parts by weight of the cationically polymerizable compound. If the amount of the benzothiazolium salt compound is less than 0.01 parts by weight, the curability of the cationically polymerizable compound will decrease, and if it exceeds 20 parts by weight, the properties of the cured product will deteriorate. On the other hand, the compounding ratio of the component (A) cationically polymerizable compound and the component (C) compound generating an active radical is 10
The compound is added in an amount of 0.01 to 20 parts by weight, preferably 0.1 to 10 parts by weight, based on 0 part.
If the amount of active radical generator is less than 0.01, the photo-curability of the cationically polymerizable compound cannot be lowered and the curing temperature cannot be lowered, and if it exceeds 20 parts by weight, the properties of the cured product deteriorate.

The curable composition of the present invention can be easily cured by light and / or heat. When the curable composition of the present invention is photocured, light having a wavelength of 500 nm or less, particularly ultraviolet rays, is preferably used, and therefore, as a light source, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, xenon is used. Lamps, carbon arc lamps, etc. are used. When thermosetting, it is used in the range of 30 to 200 ° C, preferably 60 to 180 ° C.

The curable composition of the present invention also contains α rays and β rays.
It can also be easily cured in a short time by ionizing radiation such as rays, γ rays, neutron rays and accelerated electron rays. Usually 0.5-60 Mrad for curing by ionizing radiation
A dose range of 1 to 50 Mrad can be used, with a range of 1 to 50 Mrad being preferred. It is also possible to cure by using light, ionizing radiation and heat in combination.

In the curable composition of the present invention, since the benzothiazolium salt compound component (B) is a latent thermal cationic polymerizable initiator, the cationic polymerizable compound component (A) is used.
Can be cured by heat, and thick film can be cured.

On the other hand, by using a benzothiazolium salt compound and a compound which generates an active radical upon irradiation with light, the benzothiazolium salt compound can function as a photocatalyst, so that the cationically polymerizable compound is photocured. be able to. In addition, by using a benzothiazolium salt compound and a compound that generates an active radical by heating, the decomposition temperature of the benzothiazolium salt compound will occur at a low temperature, and the cationically polymerizable compound will be heated at a lower temperature. Can be cured.

In addition to the components used in the present invention, for example, when the compound (a) having an epoxy group is used as the cationically polymerizable compound (A), it is usually used as a curing agent for epoxy resins. Hardeners such as phenolic hardeners and acid anhydride hardeners are used. Also,
If necessary, a reactive diluent, a curing accelerator, a solvent, a pigment, a dye, a coupling agent, an inorganic filler, carbon fibers, glass fibers, a surfactant, etc. may be added to the curable composition of the present invention. It is also possible to do so.

[0025]

EXAMPLES The present invention will be described in more detail below with reference to examples and comparative examples. However, the present invention is not limited to these examples. Examples 1-36 Various benzothiazolium salt compounds were dissolved in propylene carbonate, and ERL-4221 (alicyclic epoxy produced by UCC) or UVR-6410 (glycidyl epoxy produced by UCC) was added to 2.5 wt% as a pure component. And a compound capable of generating various active radicals was added to each epoxy in an amount of 2.5 parts by weight to prepare a curable composition (see Tables 1 to 4 for details of the composition contents at the time of preparation). Are shown together).

Comparative Examples 1 to 36 Curable compositions were prepared in the same manner as in Examples, except that the compound that generated active radicals was excluded. (Details of the composition contents at the time of preparation are summarized in Tables 1 to 4). Indicated).

<Preparation of Test Pieces for Test> The test pieces used in Tests I and II of Examples and Comparative Examples were prepared by using the above-mentioned curable composition so that the thickness of the tin plate was 10 μm with a doctor blade. It was prepared by coating.

(I) Photocurability test I The test piece was irradiated with 5 J / cm ² of an ultrahigh pressure mercury lamp. At this time, those in which the coating film is cured are indicated by ◯, and those which are not cured are indicated by X, in Table 1.

[0029]

[Table 101]

[0030]

[Table 102]

(Ii) Photocurability Test II The curable composition was subjected to UV-DSC measurement, and the time from UV irradiation to the top of the exothermic peak was determined and summarized in Table 2. The measurement conditions of UV-DSC are as follows. Measuring equipment of DSC: DSC220C (manufactured by Seiko Denshi Kogyo Co., Ltd.) UV irradiator: Ultra high pressure mercury lamp atmosphere: Nitrogen gas stream 30 ml / min Measurement temperature: 50 ° C Sample amount: 0.1-0.3 mg Membrane thickness : ^{2 to} 10 μm Illumination time: 15 minutes Illumination: 10 mW / cm ² (365n
m)

[0032]

[Table 201]

[0033]

[Table 202]

(Iii) Electron Beam Curability Test A test piece was irradiated with a 20 Mrad electron beam at an accelerating voltage of 175 KV. At this time, those in which the coating film is cured are indicated by ◯, and those in which the composition is thickened are indicated by Δ, in Table 3.

[0035]

[Table 301]

[0036]

[Table 302]

(Iv) Thermosetting test The compound was subjected to DSC measurement, and the exothermic onset temperature and D
The top peak temperature of the SC curve was determined and summarized in Table 4. The measurement conditions of DSC are as follows. Measuring equipment of DSC: DSC220C (Seiko Denshi Kogyo Co., Ltd.) Atmosphere: 30 ml / min in nitrogen gas stream Temperature rising speed: 10 ° C / min Sample amount: 0.3-0.8 mg

[0038]

[Table 401]

[0039]

[Table 402]

[0040]

As described above, the curable composition of the present invention can be cured at low temperature and in a short time by irradiation with light and / or heat. That is, the present invention has the following effects. (1) As a component (C) in addition to the cationically polymerizable compound (A) and the benzothiazolium salt compound (B) upon curing, a compound that generates an active radical by light or a compound that generates an active radical by heat The curing conditions can be freely selected by selecting and adding the compound as desired. (2) In the case of curing with light, when a compound that generates active radicals with light is not added, it exhibits high photocurability as compared with the case where photocuring does not proceed at all. (3) In the case of curing with heat, it is possible to cure at a much lower temperature than in the case of not adding a compound that generates active radicals with heat. Further, the thermosetting temperature can be controlled by appropriately selecting a compound that generates an active radical by heat. (4) Furthermore, it is also possible to coexist a compound that generates an active radical by light and a compound that generates an active radical by heat in the reaction system to perform photocuring, and then perform heat curing at low temperature as after cure. .. (5) Since the cured product of the composition of the present invention has excellent physical properties, it is suitably used as a material for paints, adhesives, inks and the like. (Hereafter, margin)

Claims (2)

[Claims] 1. Component (A): cationically polymerizable compound, component (B): benzothiazolium salt compound and component (C):
A curable composition containing a compound that generates active radicals. 2. The curable composition according to claim 1, wherein the compound (C) which generates an active radical is a compound which generates an active radical upon irradiation with light and / or heat.