JP2017025328A - Thermal cationic polymerizable composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal cation polymerizable composition which is cured by a cation polymerization at lower temperature for shorter time, and is useful as an electric and electronic component material where exposure to high temperature for long time is not preferable or as an adhesive or the like of such member or the like.SOLUTION: There is provided a thermal cation polymerizable composition containing a cation polymerizable material which is an epoxy compound and/or an oxetane compound, (a) an iodonium salt represented by the formula:Ar-I-ArX, where Arand Arare each independently substituted/unsubstituted aryl and Xis anion, (b) a vanadium complex and (c) a compound having an α-hydroxy ketone structure, if the case may be. The thermal cation polymerizable composition is a thermal cation polymerizable composition capable of being cured in short time even at low temperature.SELECTED DRAWING: None

Description

  The present invention relates to a thermally cationically polymerizable composition.

  Cationic polymerizable substances, typically epoxy compounds, have a cured product with excellent properties such as mechanical strength, chemical resistance, electrical insulation, and adhesive properties. Widely used in construction and adhesive fields. The epoxy compound can be cured in combination with various curing agents such as amines, polyamines, acid anhydrides, phenol resins, onium salts and the like according to the purpose.

In general, an aromatic sulfonium salt compound having at least one aliphatic group is often used to achieve low-temperature rapid curing of a cationically polymerizable substance (see, for example, Patent Document 1). However, there are still few lineups of low-temperature curing agents that start curing at around 80 ° C. In addition, the aromatic sulfonium salt contains SbF ₆ (hexafluoroantimony) as a counter anion, but has a drawback that it is difficult to handle because antimony is a controlled substance.

  Recently, an adhesive composition containing an aromatic iodonium salt compound, an organic peroxide as a radical polymerization initiator, and a cationic polymerizable substance as an adhesive that can be cured at a low temperature and speed has been reported ( For example, see Patent Document 2). However, the fast curability of the adhesive composition was observed at a curing temperature of more than 110 ° C., and the curability at a lower temperature has not been reported. Moreover, since the said adhesive composition contains an organic peroxide, the stability may become a problem.

JP-A-6-345726 JP 2011-116977 A

  An object of the present invention is to provide a thermal cationic polymerizable composition that cures by cationic polymerization at a lower temperature and in a shorter time. Another object of the present invention is to provide a thermal cationically polymerizable composition that is more stable.

As a result of intensive studies in view of the above problems, the present inventors have obtained a cationically polymerizable substance and (a) formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are independently, a substituted or unsubstituted aryl, X ^- is a iodonium salt represented by an anion), a compound having a (b) a metal complex, optionally (c) alpha-hydroxyketone structure The present inventors have found that a thermocationic polymerizable composition characterized in that it can be thermoset in a short time even at a low temperature, and has completed the present invention.

That is, the present invention is as follows:
[1] Cationic polymerizable substance and (a) Formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are independently substituted or unsubstituted aryl; ^- has a iodonium salt represented by an anion), characterized in that it comprises a (b) a metal complex, a thermal cationic polymerizable composition.
[2] The thermal cationically polymerizable composition according to the above [1], further comprising (c) a compound having an α-hydroxyketone structure.
[3] The thermal cationic polymerizability according to the above [1] or [2], which is a two-part curable composition comprising (b) a first liquid containing a metal complex and a second liquid containing other components. Composition.
[4] The thermal cationic polymerizable composition as described in [3] above, wherein the first liquid is a primer.
[5] The thermal cationic polymerizable composition according to the above [1] or [2], which is a one-component curable composition.
[6] (a) Formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are independently substituted or unsubstituted aryl, and X ⁻ is an anion. A thermal cationic polymerizable curing agent comprising an iodonium salt represented by (II) and (b) a metal complex.
[7] The thermal cationic polymerizable curing agent according to [6], further including (c) a compound having an α-hydroxyketone structure.
[8] Use of the thermal cationic polymerizable curing agent according to the above [6] or [7] in curing the cationic polymerizable substance at 80 ° C. or lower.

  Since the thermal cationic polymerizable composition of the present invention can be thermally cured in a shorter time even at a low temperature, it can be used as an electrical / electronic component material in which exposure to a high temperature for a long time is not preferable, or an adhesive for such a component, etc. Useful as such. Moreover, since the thermal cationic polymerizable composition of the present invention does not contain a component that affects liquid stability such as peroxide, it can be more excellent in stability.

The test sample used for observation of the hardening state of resin with a finger is shown. The test sample was obtained by applying (b) the first liquid (primer) 2 containing the metal complex to the slide glass 1 and drying it to 80 ° C. on a hot plate, and then adding the second liquid 3 containing other components to It was dropped to produce 10 mmφ and about 1 mm height.

  Hereinafter, embodiments of the present invention will be described in detail.

(Thermal cationic polymerizable composition)
The first aspect of the present invention comprises a cationically polymerizable substance and (a) formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are independently substituted or unsubstituted. an aryl, X ^- is an iodonium salt represented by the anion) (hereinafter, referred to as "a component"), (b) a metal complex (hereinafter, referred to as "component b"), optionally ( c) A thermal cationically polymerizable composition comprising a compound having an α-hydroxyketone structure (hereinafter referred to as “component c”). That is, the first aspect of the present invention includes a thermal cationic polymerizable composition containing a cationic polymerizable substance, a component and b component; and a cationic polymerizable substance, and a component, b component and c component. Includes thermal cationically polymerizable compositions.

  Examples of the cationically polymerizable substance include ethylenically unsaturated group-containing compounds such as epoxy compounds, oxetane compounds, polystyrene compounds, and vinyl ether compounds. Preferred is at least one compound selected from the group consisting of epoxy compounds, oxetane compounds and vinyl ether compounds, more preferred are epoxy compounds and / or oxetane compounds, and particularly preferred are epoxy compounds.

  Epoxy compounds include aromatic, aliphatic and alicyclic epoxy compounds. As aromatic epoxy compounds, bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol AD type epoxy compounds, bisphenol S type epoxy compounds, naphthalene type epoxy compounds, phenol novolac type epoxy compounds, cresol novolak type epoxy compounds, polyfunctional Specific examples thereof include bisphenol A type epoxy compounds such as EPICLON 850, 850-S and EXA-850CPR manufactured by DIC; bisphenols such as EPICLON 830-S and EXA-830LVP manufactured by DIC. F-type epoxy compound; Naphthalene-type epoxy compound such as EPICLON HP-4032D and HP-7200H manufactured by DIC; EPICLON N-740 manufactured by DIC Phenol novolac type epoxy compounds such as N-770; Cresol novolac type epoxy compounds such as EPICLON N-660, N-670, N-655-EXP-S manufactured by DIC; Tetra (hydroxyphenyl) alkane glycidyl ether, tetra Examples thereof include polyfunctional epoxy compounds such as glycidyl ether of hydroxybenzophenone and epoxidized polyvinylphenol.

  Examples of the aliphatic epoxy compound include polyglycidyl ethers of polyhydric alcohols or alkylene oxide adducts thereof. Specific examples thereof include ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, 1 , 4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerin diglycidyl ether, trimethylolpropane triglycidyl ether (Epolite 100MF manufactured by Kyoeisha Chemical Co., Ltd.), polyethylene glycol di A glycidyl ether etc. can be mentioned.

  Examples of the alicyclic epoxy compound include hydrogenated aromatic epoxy compounds, cyclohexane, cyclohexyl methyl ester, cyclohexyl methyl ether, spiro, and tricyclodecane epoxy compounds. Specific examples thereof include: Hydrogenated bisphenol A type epoxy compounds such as KRM-2408 manufactured by ADEKA, YX-8034 manufactured by JER; 3 ′, 4′-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate, 1, 2: 8,9 -1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of diepoxy limonene, 1,2-epoxy-4-vinylcyclohexane, 2,2-bis (hydroxymethyl) -1-butanol (manufactured by Daicel) Alicyclic epoxy compounds such as EHPE3150) It can gel.

  Specific examples of the oxetane compound include 3-ethyl-3-hydroxymethyloxetane (oxetane alcohol) (for example, OXT-101 manufactured by Toagosei Co., Ltd.), 2-ethylhexyl oxetane (for example, OXT-212 manufactured by Toagosei Co., Ltd.), Renbisoxetane (XDO: for example, OXT-121 manufactured by Toagosei Co., Ltd.), 3-ethyl-3 {[(3-ethyloxetane-3-yl) methoxy] methyl} oxetane (eg, OXT-221 manufactured by Toagosei Co., Ltd.) Oxetanylsilsesquioxetane (for example, OXT-191 manufactured by Toa Gosei Co., Ltd.), phenol novolac oxetane (eg, PHOX manufactured by Toa Gosei Co., Ltd.) and 3-ethyl-3-phenoxymethyloxetane (POX: for example, OXT- manufactured by Toagosei Co., Ltd.) 211).

  Specific examples of the vinyl ether compound include hydroxybutyl vinyl ether (for example, HBVE manufactured by ISP), vinyl ether of 1,4-cyclohexanedimethanol (for example, CHVE manufactured by ISP), and triethylene glycol divinyl ether (for example, DVE manufactured by ISP). -3), dodecyl vinyl ether (for example, DDVE manufactured by ISP), and cyclohexyl vinyl ether (for example, CVE manufactured by ISP).

The component a has the formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are independently substituted or unsubstituted aryl, and X ⁻ is an anion). The iodonium salt shown. Here, “aryl” means an aromatic hydrocarbon group having 6 to 18 carbon atoms, preferably a phenyl group or a naphthyl group. The aryl may be unsubstituted or substituted with one or more arbitrary substituents, and as such a substituent, a linear or branched alkyl group having 1 to 18 carbon atoms, carbon, A linear or branched alkoxy group having 1 to 18 carbon atoms, a linear or branched alkoxycarbonyl group having 2 to 18 carbon atoms, a linear or branched acyloxy group having 2 to 18 carbon atoms, a halogen atom , Cyano group, nitro group, hydroxyl group and the like. The “anion” may be a monovalent counter anion, but is preferably a non-antimony anion, for example, BF ₄ ⁻ , AsF ₆ ⁻ , or B (C ₆ F ₅ ) ₄ ⁻ , or [P (R _F ) _n F _6-n ] ⁻ , [C (R _F SO ₂ ) ₃ ] ⁻ , or [N (R _F SO ₂ ) ₂ ] ⁻ (wherein, R _F independently represents 1 to 6 or a fully fluorinated alkyl group, and n is an integer of 0 to 5).

Specific examples of the component a include diphenyliodonium hexafluoroarsenate, di (4-chlorophenyl) iodonium hexafluoroarsenate, di (4-bromophenyl) iodonium hexafluoroarsenate, phenyl (4-methoxyphenyl) Iodonium hexafluoroarsenate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium hexafluorophosphate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium tri (pentafluoroethyl) tri Fluorophosphate (for example, IK-1 manufactured by San Apro), 4-methylphenyl-4- (1-methylethyl) phenyliodonium tetrakis (pentafluorophenyl) borate (for example, manufactured by Rhodia) PI-2074), 4-methylphenyl-4- (2-methylpropyl) phenyl iodonium hexafluorophosphate (e.g., BASF Corp. IRGACURE (TM) 250), bis _{(C 10 to 14} - alkylphenyl) iodonium -Hexafluorophosphate (for example, WPI-113 manufactured by Wako Pure Chemical Industries, Ltd.) can be used. Such an iodonium salt is commercially available, for example, as a cationic initiator from a reagent supplier, and can be easily obtained.

  In the first embodiment of the present invention, the thermally cationic polymerizable composition may contain component a alone or in combination of two or more. The blending amount of the component a is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass with respect to 100 parts by mass of the cationic polymerizable substance from the viewpoint of the physical properties and colorability of the cured product. is there.

  The component b is a metal complex. The component b may be any reducing metal complex that can promote cationic polymerization by decomposing the iodonium salt of component a and generating an acid regardless of light, and preferably iron, molybdenum, vanadium, etc. And metal complexes, particularly preferably vanadium complexes. Examples of vanadium complexes include tetravalent vanadium compounds such as bis (acetylacetonato) oxovanadium (IV), bis (benzoylacetonato) oxovanadium (IV), bis (stearoyloxy) oxovanadium (IV), and oxalic acid. Examples include vanadyl and vanadyl naphthenate. Further, pentavalent vanadium compounds such as vanadium pentoxide (V), metavanadate (V) salt, and tri (alkoxy) oxovanadium (V) may be used. In the presence of an acidic compound such as a phosphate compound, the pentavalent vanadium compound is preferably a tetravalent vanadium compound in the system of the composition (particularly the first liquid of the two-component curable composition). Can be formed.

  In the first aspect of the present invention, the thermal cationic polymerizable composition may contain the component b alone or in combination of two or more, and the blending amount thereof is low temperature fast curability, colorability of the composition and storage. From the viewpoint of stability, the amount is preferably 0.001 to 5 parts by mass, more preferably 0.01 to 1 part by mass with respect to 100 parts by mass of the cationic polymerizable substance.

  The component c is a compound having an α-hydroxyketone structure. The component c accelerates the decomposition of the iodonium salt and accelerates the cationic polymerization. Examples of the compound having an α-hydroxyketone structure include benzoin (for example, Seikol Z manufactured by Seiko Chemical Co., Ltd.), 1-hydroxy-cyclohexyl-phenyl-ketone (for example, IRGACURE (registered trademark) 184 manufactured by BASF), 2-hydroxy-2-methyl-1-phenyl-1-propane (for example, DAROCUR (registered trademark) 1173 manufactured by BASF), 1- [4- (2-hydroxyethoxy) -phenyl] -2-hydroxy-2 -Methyl-1-propan-1-one (eg IRGACURE® 2959 from BASF), 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl ] Phenyl} -2-methyl-propan-1-one (for example, IRGACUR manufactured by BASF (Registered trademark) 127), oligo {2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propan-1-one} (for example, Esacure KIP 150 manufactured by Lamberti), etc. Mention may be made of initiators. Examples of the compound having an α-hydroxyketone structure include α-hydroxy acids such as glycolic acid, lactic acid, malic acid, citric acid, and tartaric acid, and ester derivatives of the above compounds. A compound having such an α-hydroxyketone structure is commercially available from a reagent supplier and can be easily obtained.

  In the first aspect of the present invention, when the thermal cationic polymerizable composition contains the component c, the component c may be used alone or in combination of two or more, and the blending amount thereof is the storage stability of the composition. From the viewpoint, the amount is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 5 parts by mass with respect to 100 parts by mass of the cationic polymerizable substance.

  The thermal cationic polymerizable composition of the present invention may be used as a one-component curable composition containing a cationic polymerizable substance, components a and b, and optionally a component c. It may be used as a divided two-component curable composition. When the stability of the composition can be ensured, it is preferably used as a one-component curable composition. When the thermal cationic polymerizable composition of the present invention is used as a two-part curable composition, the first liquid containing b component and other components (cationic polymerizable substance, a component, and optionally c component) The second liquid is preferably contained from the viewpoint of storage stability. In addition, the first liquid may be used by mixing with the second liquid immediately before its use. For example, the first liquid is not directly mixed with the second liquid, but is applied to any surface as a primer in advance and dried. The second liquid may be applied and subjected to thermosetting at a low temperature.

  The 1st liquid containing b component should just melt | dissolve and disperse | distribute b component in arbitrary solvents. The solvent to be used is not particularly limited as long as it is inert to each component and is suitable for dissolution and dispersion of component b, but is preferably an alcohol or a ketone, more preferably 1 to 1 carbon atoms. 6 alcohols or ketones, particularly preferably methanol, ethanol, acetone and the like. The concentration of the c component in the first liquid is not particularly limited, and the concentration and the coating amount may be appropriately adjusted so as to be the blending amount of the c component in the composition of the present invention.

  In addition to the component b, an acidic compound may be added to the first liquid. Such acidic compounds include acidic phosphorus compounds, organic carboxylic acids, or organic sulfonic acids. In particular, when a pentavalent vanadium compound is used as the metal complex, it is preferable to add an acidic phosphate compound that can form a tetravalent vanadium compound with the pentavalent vanadium compound in the first liquid system. Specific examples of acidic phosphorus compounds include monomethyl phosphate, dimethyl phosphate, monoethyl phosphate, diethyl phosphate, monoisopropyl phosphate, diisopropyl phosphate, monobutyl phosphate, dibutyl phosphate, mono-β-chloroethyl phosphate, di-β-chloroethyl. Acid phosphates such as phosphate, mono-β-bromoethyl phosphate, di-β-bromoethyl phosphate, monoethoxyethyl phosphate, diethoxyethyl phosphate, monobutoxyethyl phosphate, dibutoxyethyl phosphate, phenyl phosphate, diphenyl phosphate Etc. The acidic compound is desirably contained in a molar ratio of 1.5 to 3.0 with respect to the metal complex.

  As the first liquid containing the component b, a primer containing vanadium pentoxide (V) and dibutyl phosphate, or a tetravalent vanadium compound that can be formed from these can be used. For example, AT-Quickr VE (manufactured by Toagosei Co., Ltd.) can be used. The amount of the primer used is preferably 0.1 to 50 parts by mass, more preferably 0.2 to 30 parts by mass with respect to 100 parts by mass of the cationic polymerizable substance.

  The second liquid containing other components (cationic polymerizable substance, ab component, and optionally c component) is obtained by dissolving and dispersing a component and optionally c component in the cationic polymerizable substance. Good. Depending on the properties of the cationically polymerizable substance, any solvent that is inert to each component may be used, but an embodiment using a liquid cationically polymerizable substance and no solvent is preferred.

[Thermal cationic polymerizable curing agent]
The second aspect of the present invention relates to a thermal cationic polymerizable curing agent characterized by comprising a component, b component, and optionally c component. That is, the third aspect of the present invention includes a thermal cationic polymerizable curing agent containing a component and b component; and a thermal cationic polymerizable curing agent containing a component, b component and c component. The thermal cationic polymerizable curing agent of the present invention is used in curing a cationic polymerizable substance at 80 ° C. or lower.

  Examples and specific embodiments of the a component, the b component, and the c component are the same as those in the first embodiment of the present invention described above. In the second aspect of the present invention, the thermal cationic polymerizable curing agent may contain each of the component a, component b and component c alone or in combination. Moreover, the compounding ratio of each component is the same as the ratio between the components of the compounding amount of each component with respect to the cationic polymerizable substance in the first aspect of the present invention.

  The thermal cation polymerizable composition and the thermal cation polymerizable curing agent of the present invention are known additives such as inorganic fillers and reinforcing materials depending on the purpose as long as the effects of the present invention are not impaired. , Colorants, stabilizers, extenders, viscosity modifiers, tackifiers, flame retardants, UV absorbers, antioxidants, anti-discoloring agents, antibacterial agents, antifungal agents, anti-aging agents, antistatic agents, plasticizers Further, it may contain a lubricant, a smoothing agent, a foaming agent, a release agent and the like.

  Examples are shown below to clarify specific embodiments of the present invention, but the present invention is not limited to only the examples shown here.

Each composition of the examples and comparative examples was prepared using the following raw materials.
〔Epoxy resin〕
-Bisphenol A type epoxy resin (manufactured by DIC, EPICLON EXA-CRP);
-Trimethylolpropane triglycidyl ether (manufactured by Kyoeisha Chemical Co., Epolite 100MF).

[Iodonium salt (component a)]
4-methylphenyl-4- (1-methylethyl) phenyliodonium tetrakis (pentafluorophenyl) borate (Rhodia, PI-2074).

[Metal complex (component c)]
-AT-Quickr VE (manufactured by Toagosei Co., Ltd.).

[Compound having α-hydroxyketone structure (component c)]
1-hydroxy-cyclohexyl-phenyl-ketone (manufactured by BASF, IRGACURE® 184).

Examples 1-3 / Comparative Examples 1-2
[Preparation conditions]
The thermal cationic polymerizable compositions of Examples 1 to 3 were prepared as two-component curable compositions.
As the first liquid, AT-Quickr VE (manufactured by Toagosei Co., Ltd.) was used. This was used as a primer.
The second liquid is based on the formulation shown in Table 1, and each of the two epoxy compounds (each 25 g, total 50 g) is added with each component excluding the component b (a, and in some cases c component). Under stirring, the mixture was stirred until it became transparent.
On the other hand, the compositions of Comparative Examples 1 and 2 were prepared using the formulation shown in Table 1 as one solution.

[Evaluation conditions]
The fast curing properties at low temperatures of the compositions of Examples 1 to 3 and Comparative Examples 1 and 2 prepared above were evaluated as follows.

In Examples 1 to 3, 100 mg of the first liquid (primer) was applied to a slide glass (26 mm × 76 mm) and dried (0.05 mg / mm ² ). Next, the glass slide was transferred onto a hot plate heated to 80 ° C. and left until it reached a steady state (about 15 minutes). The dry weight of the primer was 0.0025 mg / mm ² . The second liquid was added dropwise so as to have a height of 10 mmφ and a height of about 1 mm (set to time 0), and observation of the cured state of the composition of the present invention was started. The evaluation was performed with a tentacle at each time.
On the other hand, in Comparative Examples 1 and 2, a slide glass (26 mm × 76 mm) was placed on a hot plate heated to 80 ° C. and allowed to stand until it reached a steady state (about 15 minutes). The prepared one-component composition was added dropwise so as to have a height of 10 mmφ and about 1 mm (set to 0 point), and observation of the cured state was started. The evaluation was performed with a tentacle at each time.
The results are shown in Table 1.

  It was confirmed that the thermal cationic polymerizable composition of the present invention prepared as a two-component curable composition was cured at a low temperature of 80 ° C. in a short time. On the other hand, the composition in which the a component and the c component were added to the cationic polymerization substance (Comparative Example 1) and the composition in which only the a component was added to the cationic polymerization substance (Comparative Example 2) were tested at an experimental temperature (80 ° C.). Then, the iodonium salt was thermally stable, and its action as an initiator could not be confirmed.

DESCRIPTION OF SYMBOLS 1 Slide glass 2 (c) The layer formed from the 1st liquid (primer) containing a metal complex 3 The 2nd liquid containing other components

Claims (9)

A cationically polymerizable substance that is an epoxy compound and / or an oxetane compound;
(A) represented by the formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are each independently substituted or unsubstituted aryl, and X ⁻ is an anion). Iodonium salt,
(B) a vanadium complex;
(C) a thermal cationic polymerizable composition comprising a compound having an α-hydroxyketone structure and cured at 80 ° C. or lower (however, a thermal cationic polymerizable composition containing an ethylenically unsaturated monomer) except). A cationically polymerizable substance that is an epoxy compound and / or an oxetane compound;
(A) represented by the formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are each independently substituted or unsubstituted aryl, and X ⁻ is an anion). Iodonium salt,
(B) a vanadium complex;
(C) A thermal cationic polymerizable composition, comprising a compound having an α-hydroxyketone structure.   The thermal cationic polymerizable composition according to claim 1 or 2, which is a two-part curable composition comprising (b) a first liquid containing a vanadium complex and a second liquid containing other components.   The thermal cationic polymerizable composition according to claim 3, wherein the first liquid is a primer.   The thermal cationic polymerizable composition according to claim 1 or 2, which is a one-component curable composition. (A) represented by the formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are each independently substituted or unsubstituted aryl, and X ⁻ is an anion). Iodonium salt,
(B) a vanadium complex;
(C) Thermal cation polymerizability in curing at 80 ° C. or lower of a polymerizable substance comprising a cationic polymerizable substance that is an epoxy compound and / or an oxetane compound, comprising a compound having an α-hydroxyketone structure Curing agent. (A) represented by the formula: Ar ¹ -I ⁺ -Ar ² .X ⁻ (wherein Ar ¹ and Ar ² are each independently substituted or unsubstituted aryl, and X ⁻ is an anion). Iodonium salt,
(B) a vanadium complex;
(C) A thermal cationic polymerizable curing agent for a cationic polymerizable substance which is an epoxy compound and / or an oxetane compound, comprising a compound having an α-hydroxyketone structure.   Use of the thermal cationic polymerizable curing agent according to claim 7 in curing the cationic polymerizable substance at 80 ° C or lower.   The thermal cationic polymerizable composition according to any one of claims 1 to 5, which is an adhesive for electric / electronic parts.

Images