JP3353323B2 - Curable composition containing benzothiazolium salt compound - Google Patents

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 cures at a low temperature and in a short time by light irradiation and / or heat. Since the cured product of the composition has excellent physical properties, it is suitably used as a material for paints, adhesives, inks, and the like.

[0002]

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

[0003]

A compound obtained by cationically polymerizing a cationically polymerizable compound such as an epoxy compound has a smaller curing shrinkage and a lower curing time than a compound obtained by radically curing a radically polymerizable compound such as an acrylic compound. It has various features 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 a sulfonium salt-based catalyst and an iron-allene complex. These catalysts exhibit high photoactivity, but cannot cure the cationically polymerizable composition by heating in a temperature range usually used. For this reason, there is a problem that a thick film cannot be cured even if heat treatment is performed after photocuring. On the other hand, JP-A-58-
37003, JP-A-63-223002, JP-A-2-1
78319, and the catalysts described in JP-A-3-17119, etc., cannot cure the cationically polymerizable compound by light irradiation because of the thermal catalyst, and many of them have a high temperature at which the polymerization is started. There's a problem. Further, although the catalyst described in JP-A-2-196812 describes that a cationically polymerizable compound can be cured by heating and light irradiation, the catalytic activity is remarkable in the case of photocuring. Low.

[0004] Accordingly, a cationic polymerization catalyst exhibiting high activity for 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 it is an object of the present invention to provide a high-performance curable composition that can cure a cationically polymerizable compound at a low temperature and in a short time by light irradiation and / or heat. The purpose is.

[0005]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and found that in the case of photocuring,
By using a benzothiazolium salt compound and 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 was possible. In addition, in the case of thermal curing, by using a benzothiazolium salt compound and a compound that generates an active radical upon heating, the decomposition temperature of the benzothiazolium salt compound is found to occur at a lower temperature, and the cationic polymerizable compound is found. Can be cured at a low temperature and in a short time by light and / or heat.

The present invention relates to a curable composition comprising a component (A): a cationically polymerizable compound, a component (B): a benzothiazolium salt compound, and a component (C): a compound generating an active radical. is there.

Hereinafter, the present invention will be described in detail. Examples of the cationically polymerizable compound as the component (A) used in the present invention include the following compounds. (A) As the compound having an epoxy group, 1,1,3-
Tetradecadiene dioxide, limonenedioxide, 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 p-cresol novolak type epoxy resins, phenol novolak type epoxy resins, and epoxy compounds such as polyglycidyl ethers of polyhydric alcohols.

(B) As the vinyl compound, styrene, α
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 Divinyl ethers such as triethylene glycol vinyl ether and cyclohexanediol divinyl ether; aralkyl divinyl ethers such as 1,4-benzene dimethanol divinyl ether, Nm-chlorophenyldiethanolamine divinyl ether and m-phenylenebis (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.

(C) As a 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 and the like (d) Spiro orthocarbonate compounds include
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-1,4,4
6-trioxaspiro [4,4] nonane, 1,4,6-
Spiroorthoester 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 particularly preferably used.

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

[0011]

Embedded image [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 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;
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]

Embedded image [In the formula, R ₆ represents a hydrogen atom, an alkyl group or a cyano group, R ₇ represents an alkyl group or a phenyl group which may be substituted and substituted, and R ₈ represents a hydrogen atom, an alkyl group, a halogen atom, 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]

Embedded image [Wherein, 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 (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. A cinnamyl halide such as cinnamyl bromide and a benzazole or benzothiazole derivative are reacted in equimolar amounts, if necessary, in the presence of a solvent such as methyl alcohol, acetone, or acetonitrile at room temperature to 80 ° C. for several hours to 30 days. 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) Compounds that generate active radicals upon irradiation with light The compounds that generate active radicals upon irradiation with light include:
Commonly known photoradical initiators can be used, and examples thereof include benzyl, benzoin ether, benzyl ketal, benzophenone, and thioxanthone. In addition, azo compounds such as azoisobutyronitrile, azide compounds, disulfide compounds, peroxide compounds and the like can be applied. Particularly, a ketone-based photoradical 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 , Benzuanthrone, 9,10-phenanthrenequinone xanthone and the like.

(B) Compounds that generate active radicals upon heating Examples of compounds that generate active radicals upon heating include azo compounds such as azoisobutyronitrile, azide compounds, disulfide compounds, and peroxides which are generally known. Compounds and the like are applied. Particularly, a peroxide compound is preferably applied, and for example, the following compounds are used. 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: acetylcyclohexylsulfonyl peroxide, tetra (t-butylperoxycarbonyl) benzophenone and the like can be applied. In particular, aromatic diacyl peroxides and peroxyesters are preferably used.

The mixing ratio of the cationically polymerizable compound of the component (A) and the benzothiazolium salt compound of the component (B) is as follows:
The benzothiazolium salt compound is added in an amount of 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 part 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 decrease. On the other hand, the compounding ratio of the cationically polymerizable compound of the component (A) and the compound that generates an active radical of the component (C) is as follows.
The compound generating activity is added in an amount of 0.01 to 20 parts by weight, preferably 0.1 to 10 parts by weight, based on 0 parts.
If the amount of the active radical generator is less than 0.01, the photocurability of the cationically polymerizable compound cannot be reduced and the curing temperature cannot be reduced. If the amount exceeds 20 parts by weight, the properties of the cured product are deteriorated.

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 light, is suitably used. Therefore, as a light source, a low-pressure mercury lamp, a medium-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a metal halide lamp, xenon Lamps, carbon arc lamps and the like are used. In the case of thermosetting, it is used in the range of 30 to 200 ° C, preferably 60 to 180 ° C.

Further, the curable composition of the present invention comprises α ray, β ray
It can be easily cured in a short time by ionizing radiation such as gamma rays, gamma rays, neutron rays and accelerating electron beams. In the case of curing by ionizing radiation, usually 0.5 to 60 Mrad
Can be used, with a range of 1 to 50 Mrad being preferred. In addition, it is also possible to cure using a combination of light, ionizing radiation and heat.

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)
Can be cured by heat, and a thick film can be cured.

On the other hand, by using a benzothiazolium salt compound and a compound that 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 when heated, the decomposition temperature of the benzothiazolium salt compound is caused to occur at a low temperature, and the cationically polymerizable compound is heated at a lower temperature. Can be cured.

In addition to the components used in the present invention, for example, when the compound having an epoxy group of the above (a) is used as the cationically polymerizable compound of the component (A), it is generally used as a curing agent for an epoxy resin. Curing agents such as phenol-based curing agents and acid anhydride curing agents are used. Also,
If necessary, the curable composition of the present invention is used by adding a reactive diluent, a curing accelerator, a solvent, a pigment, a dye, a coupling agent, an inorganic filler, a carbon fiber, a glass fiber, a surfactant and the like. It is also possible.

[0025]

EXAMPLES The present invention will be described more specifically with reference to examples and comparative examples. However, the present invention is not limited to these examples. Examples 1 to 36 Various benzothiazolium salt compounds were dissolved in propylene carbonate, and 2.5 parts by weight as pure components were added to ERL-4221 (alicyclic epoxy manufactured by UCC) or UVR-6410 (glycidyl epoxy manufactured by UCC). Parts, 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 (details of the composition at the time of preparation are shown in Tables 1 to 4). Are shown together).

Comparative Examples 1-36 Curable compositions were prepared in the same manner as in the Examples except that the compounds generating active radicals were omitted (Details of the composition at the time of preparation are summarized in Tables 1 to 4). Shown).

<Preparation of Test Piece for Test> The test piece used in Tests I and II of Examples and Comparative Examples was prepared by using the above-mentioned curable composition so as to have a thickness of 10 μm on a tin plate with a doctor blade. It was prepared by coating.

[0028] (i) was photocurable Test I Test piece with ultra-high pressure mercury lamp 5 J / cm ² was irradiated. At this time, the cured coating film was indicated by １, and the cured coating film was indicated by × in Table 1.

[0029]

[Table 101]

[0030]

[Table 102]

(Ii) Photocurability Test II The cured composition was subjected to UV-DSC measurement, and the time from UV irradiation to the top of the exothermic peak was determined. The results are shown in Table 2. In addition, the measurement conditions of UV-DSC are as follows. DSC measuring device: DSC220C (manufactured by Seiko Instruments Inc.) UV irradiator: ultra-high pressure mercury lamp Atmosphere: 30 ml / min in nitrogen gas flow Measurement temperature: 50 ° C. Sample amount: 0.1 to 0.3 mg Film thickness : ^{2 to} 10 μm Irradiation 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 20 Mrad electron beam at an acceleration voltage of 175 KV. At this time, the cured coating film was indicated by ○, and the thickened composition was indicated by △ in Table 3.

[0035]

[Table 301]

[0036]

[Table 302]

(Iv) Thermosetting Test The blend was subjected to DSC measurement, and the exothermic onset temperature and D
The top peak temperature of the SC curve was determined and is summarized in Table 4. The measurement conditions for DSC are as follows. DSC measuring instrument: DSC220C (Seiko Denshi Kogyo) Atmosphere: Nitrogen gas flow 30 ml / min Heating rate: 10 ° C./min Sample amount: 0.3 to 0.8 mg

[0038]

[Table 401]

[0039]

[Table 402]

[0040]

As described above, the curable composition of the present invention can be cured at a low temperature in a short time by light irradiation and / or heat. That is, the present invention has the following effects. (1) In addition to the cationically polymerizable compound (A) and the benzothiazolium salt compound (B) upon curing, as a component (C), a compound that generates an active radical by light or a compound that generates an active radical by heat , Can be selected as desired, and the curing conditions can be freely selected. (2) In the case of curing with light, when a compound that generates active radicals by light is not added, high photocurability is exhibited as compared with the case where photocuring does not proceed at all. (3) In the case of curing with heat, curing can be performed at a much lower temperature than in the case where a compound that generates active radicals by heat is not added. Further, by appropriately selecting a compound that generates an active radical by heat, the thermosetting temperature can be controlled. (4) Further, after a compound that generates an active radical by light and a compound that generates an active radical by heat coexist in a reaction system and photocured, it is also possible to thermally cure at a low temperature as an 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. (Hereinafter, margin)

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-57-209931 (JP, A) JP-A-2-189548 (JP, A) JP-A-4-1205 (JP, A) JP-A-3-203 293670 (JP, A) JP-A-2-268173 (JP, A) Kenichi Koseki, Journal of the Chemical Society of Japan, Japan, 1986, No. 9, pp. 1234-1240 (58) Fields investigated (Int. Cl. ⁷ , DB name) C08F 4/00-4/82 CA (STN) REGISTRY (STN)

Claims (1)

(57) [Claims] 1. Component (A): a cationically polymerizable compound, component (B): a benzothiazolium salt compound represented by any of formulas (1) to (3) and component (C): Light irradiation and or
A curable composition containing a compound that generates active radicals by heat . Embedded image (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 R ₄ represents a hydrogen atom, a halogen atom, an alkyl group, an optionally substituted phenyl group or an alkylthio group, and R ₅ represents a hydrogen atom, a halogen atom, an alkyl group, or a phenyl group. X represents SbF ₆ , AsF ₆ , PF ₆ ,
Or representing the BF _4. ) (Wherein, 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, R ₉ 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 . ) (Wherein, R ₁₀ and R ₁₁ represent a hydrogen atom, a halogen atom, an alkyl group, or an alkoxy group; R ₁₂ represents a hydrogen atom, an alkyl group, or an optionally substituted phenyl group or an alkylthio group; ₁₃ represents a hydrogen atom, a halogen atom, an alkyl group, a phenyl group which may be substituted,
Represents SbF ₆ , AsF ₆ , PF ₆ , or BF ₄ . )