WO2021117396A1

WO2021117396A1 - Cationically curable composition, cured product, and joined body

Info

Publication number: WO2021117396A1
Application number: PCT/JP2020/041710
Authority: WO
Inventors: 寛人松岡
Original assignee: 株式会社スリーボンド
Priority date: 2019-12-11
Filing date: 2020-11-09
Publication date: 2021-06-17
Also published as: JPWO2021117396A1; CN114761460B; TW202122444A; CN114761460A

Abstract

The purpose of the present invention is to provide a cationically curable composition that exhibits an excellent adhesiveness with aluminum die castings, PPS, and the like, while retaining photocurability and low-temperature curability.　The present invention is a cationically curable composition that contains components (A) to (E) and contains 12-100 parts by mass of component (E) per a total of 100 parts by mass of component (A) and component (B). Component (A) is an aromatic epoxy resin, component (B) is at least one among a hydrogenated epoxy resin (B1) and an alicyclic epoxy resin (B2), component (C) is a photo-cationic polymerization initiator, component (D) is a thermal cationic polymerization initiator, and component (E) is a polycaprolactone polyol that has at least three hydroxyl groups and a molecular weight of not more than 1,700.

Description

Cationic curable compositions, cured products and conjugates

The present invention relates to cationic curable compositions, cured products and conjugates.

Conventionally, a cationically curable composition containing an epoxy resin or the like is excellent in adhesiveness, sealing property, high strength, heat resistance, electrical properties, and chemical resistance. Therefore, an adhesive, a sealing agent, a potting agent, and a coating are used. It has been used in various applications such as agents and conductive pastes. In addition, the objects are diverse, and particularly in electronic and electrical equipment, they are used for liquid crystal displays, organic electroluminescence, flat panel displays such as touch panels, hard disk devices, mobile terminal devices, semiconductors, camera modules and the like.

Japanese Unexamined Patent Publication No. 59-204676 discloses a photocationic polymerizable resin composition containing an epoxy resin and a photocationic polymerization initiator that generates Lewis acid by irradiation with active energy rays such as ultraviolet rays. .. In addition, International Publication No. 2005/05/9002 (corresponding to US Patent Application Publication No. 2007/0208106) contains a cation containing an epoxy resin component, a photocationic polymerization initiator, a thermal cationic polymerization initiator, and a filler. Curable epoxy resin compositions are disclosed.

However, the cationically polymerizable resin composition disclosed in JP-A-59-204676 has a problem that it cannot cure a portion not exposed to light. In order to solve this problem, it is possible to generate an acid from the cation initiator and cure it by heating it to about 200 ° C. However, since the curing conditions are too high, the liquid crystal display is easily deteriorated by heat. There is a problem that it is difficult to apply it to applications such as elements and organic EL elements. On the other hand, the cationically curable epoxy resin composition disclosed in International Publication No. 2005/05/9002 (corresponding to US Patent Application Publication No. 2007/0208106) has a relatively low temperature in places not exposed to light. Although thermal cationic polymerization initiators have been formulated and improved so that they can be cured, their adhesiveness to electronic / electrical component modules, aluminum die cast, which is widely used as a material for in-vehicle components, polyphenylene sulfide (PPS), etc. is inferior in recent years. It was a thing.

An object of the present invention is to solve the above-mentioned problems, that is, to provide a cationically curable composition having excellent adhesiveness to aluminum die-cast, PPS, etc. while maintaining photocurability and low-temperature curability. It is in.

The present invention overcomes the above-mentioned conventional problems. That is, the present invention has the following gist.

[1] Cation curing containing the following components (A) to (E) and containing 12 to 100 parts by mass of the component (E) with respect to 100 parts by mass of the total amount of the components (A) and (B). Sex composition:
Component (A): Aromatic epoxy resin (B) Component: At least one of hydride epoxy resin (B1) and alicyclic epoxy resin (B2) (C) Component: Photocationic polymerization initiator (D) Component: Thermal cation Polymerization initiator (E) component: A polycaprolactone polyol having a trifunctional or higher functional hydroxyl group and having a molecular weight of 1700 or less.

[2] The cation curing according to the above [1], wherein the content of the component (B) is 10 to 80 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). Sex composition.

[3] At least one of the components (D) selected from the group consisting of an aromatic sulfonium-based thermal cationic polymerization initiator, an aromatic iodonium-based thermal cationic polymerization initiator, and a thermal cationic polymerization initiator containing an amine salt. The cationic curable composition according to the above [1] or [2].

[4] The cationic curable composition according to any one of the above [1] to [3], wherein the component (D) is a thermal cationic polymerization initiator containing a salt having a quaternary ammonium cation.

[5] The cationic curable composition according to any one of the above [1] to [4], wherein the component (C) contains at least one of an aromatic iodonium salt and an aromatic sulfonium salt.

[6] The above-mentioned [1], wherein the component (A) contains at least one selected from the group consisting of an aromatic bisphenol A type epoxy resin, an aromatic bisphenol F type epoxy resin, and an aromatic bisphenol E type epoxy resin. ] To [5], the cationic curable composition according to any one of the above items.

[7] The item according to any one of [1] to [6] above, wherein the component (B) contains only one of the hydrogenated epoxy resin (B1) and the alicyclic epoxy resin (B2). Cation curable composition.

[8] The cationically curable composition according to any one of [1] to [6] above, wherein the component (B) contains a hydrogenated epoxy resin (B1) and an alicyclic epoxy resin (B2). ..

[9] The cationically curable composition according to any one of the above [1] to [8], which is used for an adhesive.

[10] The cationically curable composition according to any one of the above [1] to [8], which is used for an adhesive whose adherend is aluminum die-cast or PPS.

[11] A cured product of the cationically curable composition according to any one of the above [1] to [10].

[12] A bonded body obtained by adhering an adherend using the cationically curable composition according to any one of the above [1] to [10].

Hereinafter, the present invention will be described in detail. In addition, in this specification, "X to Y" is used in the meaning that the numerical values (X and Y) described before and after it are included as the lower limit value and the upper limit value, and means "X or more and Y or less".

<Cation curable composition>
The components (A) to (E) contained in the cationically curable composition of the present invention are as follows.

Component (A) Component: Aromatic epoxy resin (B) Component: At least one of hydride epoxy resin (B1) and alicyclic epoxy resin (B2) (C) Component: Photocationic polymerization initiator (D) Component: Thermal cation Polymerization initiator (E) component: A polycaprolactone polyol having a trifunctional or higher functional hydroxyl group and having a molecular weight of 1500 or less.

<Ingredient (A)>
The aromatic epoxy resin, which is the component (A) of the present invention, is a compound that undergoes a cross-linking reaction with a cationic species generated from a cationic polymerization initiator by irradiation or heating with active energy rays. The type of the component (A) is not particularly limited, and for example, an aromatic bisphenol A type epoxy resin, an aromatic bisphenol F type epoxy resin, an aromatic bisphenol E type epoxy resin, and an aromatic bisphenol A type alkylene oxide adduct. Diglycidyl ether, diglycidyl ether of aromatic bisphenol F type alkylene oxide adduct, diglycidyl ether of aromatic bisphenol E type alkylene oxide adduct, aromatic novolac type epoxy resin, urethane modified aromatic epoxy resin, nitrogen Examples thereof include rubber-modified aromatic epoxy resins containing a contained aromatic epoxy resin, polybutadiene, nitrile butadiene rubber (NBR) and the like. Among these, from the viewpoint of obtaining a cationically curable composition having excellent adhesiveness to aluminum die cast, PPS, etc., aromatic bisphenol A type epoxy resin, aromatic bisphenol F type epoxy resin, or aromatic bisphenol E type Epoxy resin is preferred.

Examples of commercially available aromatic epoxy resins include jER (registered trademark, the same applies hereinafter) 825, jER827, jER828, jER828EL, jER828US, jER828XA, jER834, jER806, jER806H, jER807, jER807ST, jER604, jER630 (above, Mitsubishi). Chemical Co., Ltd.), EPICLON (registered trademark, the same applies hereinafter) 830, EPICLON EXA-830LVP, EPICLON EXA-850CRP, EPICLON 835LV, EPICLON HP4032D, EPICLON 703, EPICLON 720, EPICLON 726, EPICLON N-680, EPICLON N-695, EPICLON N-655-EXP-S, EPICLON N-665-EXP-S, EPICLON N-685-EXP-S, EPICLON N-740, EPICLON N-775, EPICLON N-865 (The above is manufactured by DIC Corporation), Adeka Resin (registered trademark, the same applies hereinafter) EP4100, Adeka Resin EP4000, Adeka Resin EP4080, Adeka Resin EP4085, Adeka Resin EP4088, Adeka Resin EP4100HF, Adeka Resin EP4901HF, Adeka Resin EP4901HF, Adeka Resin EP4000S, Adeka Resin EP4000S EP4010L (above, manufactured by ADEKA Corporation), Denacol (registered trademark, same below) EX-614B, Denacol EX-411, Denacol EX-314, Denacol EX-201, Denacol EX-212, Denacol EX-252 (above, Nagase) (Made by Chemtex Co., Ltd.), etc., but are not limited to these. These aromatic epoxy resins may be used alone or in combination of two or more.

<Ingredient (B)>
The component (B) of the present invention is at least one of a hydrogenated epoxy resin (B1) and an alicyclic epoxy resin (B2), and is crosslinked by a cationic species generated from a cationic polymerization initiator by irradiation or heating with active energy rays. It is a compound that causes a reaction. The hydrogenated epoxy resin (B1) and the alicyclic epoxy resin (B2) may be used alone, or the hydrogenated epoxy resin (B1) and the alicyclic epoxy resin may be used in combination. When the hydrogenated epoxy resin (B1) and the alicyclic epoxy resin (B2) are used alone, they are more preferable because they are more excellent in adhesiveness to aluminum die casting. Further, when these are used in combination, they are preferable because they have an excellent balance between photocurability and low-temperature curability and can maintain appropriate adhesiveness to various members. The hydrogenated epoxy resin (B1) is a compound without an unsaturated bond obtained by nuclear hydrogenation of the aromatic ring of an aromatic epoxy resin.

The type of the hydrogenated epoxy resin (B1) is not particularly limited, and for example, hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, hydrogenated bisphenol E type epoxy resin, and hydrogenated bisphenol A type alkylene. Examples thereof include diglycidyl ether as an oxide adduct, diglycidyl ether as an alkylene oxide adduct of bisphenol hydride, phenol novolac epoxy resin hydrogenated, and cresol novolac epoxy resin hydrogenated. Among these, hydrogenated bisphenol A type epoxy resin, hydrogenated bisphenol F type epoxy resin, or hydrogenated bisphenol E type from the viewpoint of obtaining a cationically curable composition having excellent adhesion to aluminum die cast, PPS, etc. Epoxy resin is preferred.

Commercially available products of hydrogenated bisphenol A type epoxy resin include, for example, jER YX-8000, jER YX-8034 (all manufactured by Mitsubishi Chemical Corporation), EPICLON EXA-7015 (manufactured by DIC Corporation), ST-3000 (Nippon). Examples include Iron Chemical & Materials Co., Ltd.), Rica Resin HBE-100 (manufactured by New Japan Chemical Co., Ltd.), Denacol EX-252 (manufactured by Nagase ChemteX Corporation), and the like. Examples of commercially available hydrogenated bisphenol F-type epoxy resins include YL-6753 (manufactured by Mitsubishi Chemical Corporation).

Examples of the alicyclic epoxy resin (B2) include compounds having a functional group represented by the following formula (1). More specific examples are not particularly limited, but for example, 3,4-epoxycyclohexylmethyl (3', 4'-epoxy) cyclohexanecarboxylate, ε-caprolactone modified 3', 4'-epoxycyclohexylmethyl, 3 , 4-epoxycyclohexanecarboxylate, bis (3,4-epoxycyclohexyl) adipate, 1,2-epoxy-4-vinylcyclohexane, 1,4-cyclohexanedimethanol diglycidyl ether, epoxyethyldivinylcyclohexane, diepoxyvinylcyclohexane , 1,2,4-Triepoxyethylcyclohexane, limonendioxide, alicyclic epoxy group-containing silicone oligomer and the like. Among these, 3,4-epoxycyclohexylmethyl (3', 4'-epoxy) cyclohexanecarboxylate, ε-, from the viewpoint of obtaining a cationically curable composition having excellent adhesiveness to aluminum die cast, PPS, etc. Caprolactone-modified 3', 4'-epoxycyclohexylmethyl, 3,4-epoxycyclohexanecarboxylate, bis (3,4-epoxycyclohexyl) adipate, 1,2-epoxy-4-vinylcyclohexane, or 1,4-cyclohexanedi Methanol diglycidyl ether is preferred.

Commercially available products of the alicyclic epoxy resin (B2) are not particularly limited, but for example, seroxide (registered trademark) 2081 (3', 4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate) and seroxide (registered). Trademark) 2021P (3', 4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate), seroxide (registered trademark) 2000 (1,2-epoxy-4-vinylcyclohexane), seroxide (registered trademark) 3000 (1) -Methyl-4- (2-methyloxylanyl) -7-oxabicyclo [4.1.0] heptane), EHPE3150 (1,2-epoxy of 2,2-bis (hydroxymethyl) -1-butanol- 4- (2-oxylanyl) cyclohexane adduct) (above, manufactured by Daicel Co., Ltd.), TTA21 (manufactured by Jiangsu TeraChem), X-40-2670, X-22-169AS, X-22-169B (above, Shinetsu Chemical Co., Ltd.) (Manufactured by Kogyo Co., Ltd.), etc., but is not limited to these.

The amount of the component (B) added is not particularly limited, but the amount of the component (B) may be 10 to 95 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). It is preferably 20 to 90 parts by mass, more preferably 30 to 85 parts by mass. The amount of the hydrogenated epoxy resin added to the component (B) is not particularly limited with respect to 100 parts by mass of the component (A), but is preferably in the range of 50 to 700 parts by mass, more preferably 100 to 600 parts. It is in the range of parts by mass, more preferably in the range of 150 to 550 parts by mass. The amount of the alicyclic epoxy resin added as the component (B) is not particularly limited with respect to 100 parts by mass of the component (A), but is preferably in the range of 20 to 300 parts by mass, and more preferably 50 to 50 parts by mass. It is in the range of 250 parts by mass, more preferably 70 to 200 parts by mass. By setting the amount of the component (B) added within the above range, a cationically curable composition having further excellent adhesiveness to aluminum die-casting, PPS and the like can be provided.

When the hydride epoxy resin (B1) and the alicyclic epoxy resin (B2) are used in combination as the component (B), the alicyclic epoxy resin (B1) is 100 parts by mass based on the alicyclic epoxy resin (B1). B2) is preferably used in the range of 10 to 300 parts by mass, more preferably 30 to 150 parts by mass, and further preferably 40 to 100 parts by mass. When the hydrogenated epoxy resin (B1) and the alicyclic epoxy resin (B2) are used in combination as the component (B), the ratio of the component (A) to the component (B) is as described above. By setting the amount of the component (B1) and the component (B2) to be within the above range, the photocurability and the low-temperature curability are well-balanced, and an appropriate adhesiveness to various members can be maintained.

<Ingredient (C)>
The component (C) of the present invention is a photocationic polymerization initiator, which is a compound that generates a cationic species by irradiation with active energy rays. The type of the component (C) is not particularly limited, and examples thereof include onium salts such as aromatic sulfonium salts and aromatic iodonium salts. The component (C) may be used alone or in combination of two or more. The cationic polymerization initiator having activity on both active energy rays and heat is treated as the component (C) in the present invention.

Moreover, as the aromatic iodonium salt, a salt containing an iodonium ion in which two groups bonded to an iodine atom are aryl groups can be mentioned. More specifically, for example, diphenyliodonium tetrakis (pentafluorophenyl) borate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroantimonate, di (4-nonylphenyl) iodonium hexafluorophosphate, 4-methylphenyl-4- Examples thereof include (1-methylethyl) phenyliodonium tetrakis (pentafluorophenyl) borate and the like.

Commercially available products of the aromatic iodonium salt include, for example, Omnicat (registered trademark) 250 (manufactured by IGM Resins VV), Bluesil PI 2074 (manufactured by Rhodia, 4-methylphenyl-4- (1-methylethyl)). ) Phenyliodonium-tetrakis (pentafluorophenyl) borate), B2380 (bis (4-tert-butylphenyl) iodonium hexafluorophosphate), B2381, D2238, D2248, D2253, I0591 (all manufactured by Tokyo Kasei Kogyo Co., Ltd.) , WPI-113 (bis [4-n-alkyl (C10-13) phenyl] iodonium hexafluorophosphate), WPI-116 (bis [n-alkyl (C10-13) phenyl] iodonium hexafluoroantimonate), WPI-169, WPI-170 (bis (4-tert-butylphenyl) iodonium hexafluorophosphate), WPI-124 (bis [4-n-alkyl (C10-13) phenyl] iodonium tetrakisfluorophenylborate) ( As mentioned above, Fujifilm Wako Junyaku Co., Ltd.) and the like can be mentioned.

Examples of the aromatic sulfonium salt include sulfonium ions in which all three groups bonded to the sulfur atom are aryl groups. More specifically, for example, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium tetrakis (pentafluorophenyl) borate, 4,4'-bis [diphenylsulfonio] diphenylsulfide-bishexa. Fluorophosphate, 4,4'-bis [di (β-hydroxyethoxy) phenylsulfonio] diphenylsulfide-bishexafluoroantimonate, 4,4'-bis [di (β-hydroxyethoxy) phenylsulfonio] diphenylsulfide -Bishexafluorophosphate, 7- [di (p-toluyl) sulfonio] -2-isopropylthioxanthone hexafluoroantimonate, 7- [di (p-toluyl) sulfonio] -2-isopropylthioxanthone tetrakis (pentafluorophenyl) borate , 4-Phenylcarbonyl-4'-diphenylsulfonio-diphenylsulfide-hexafluorophosphate, 4- (p-ter-butylphenylcarbonyl) -4'-diphenylsulfonio-diphenylsulfide-hexafluoroantimonate, 4-( P-ter-butylphenylcarbonyl) -4'-di (p-toluyl) sulfonio-diphenylsulfide-tetrakis (pentafluorophenyl) borate, 4-methylphenyl-4- (1-methylethyl) phenyliodonium-tetrakis (penta) Fluorophenyl) borate and the like can be mentioned. However, it is not limited to these. These aromatic sulfonium salts may be used alone or in combination of two or more.

Commercially available products of the aromatic sulfonium salt include, for example, ADEKA ARCLUDS (registered trademark, the same applies hereinafter) SP-150, ADEKA ARCULUS SP-170, ADEKA ARCLUDS SP-172 (all manufactured by ADEKA Corporation), and CPI. -100P, CPI-101A, CPI-110B, CPI-200K, CPI-210S (all manufactured by San-Apro Co., Ltd.), T1608, T1609, T2041 (Tris (4-methylphenyl) sulfonium hexafluorophosphate), T2042 (Tri) -P-Trilsulfonium trifluoromethanesulfonate) (above, manufactured by Tokyo Kasei Kogyo Co., Ltd.), Cyracure UVI-6990, Cyracure UVI-6974 (above, manufactured by Union Carbide), DTS-200 (manufactured by Midori Chemical Co., Ltd.), etc. Can be mentioned.

The blending amount of the component (C) in the cationically curable composition of the present invention is not particularly limited, but is 0.1 to 30 parts by mass with respect to 100 parts by mass of the total amount of the components (A) and (B). It is preferably in the range of 0.5 to 15 parts by mass, more preferably in the range of 0.5 to 15 parts by mass. When the content of the component (C) is 0.1 part by mass or more with respect to 100 parts by mass of the total amount of the component (A) and the component (B), sufficient photocurability can be obtained and 30 parts by mass. The following is preferable from the viewpoint of excellent adhesion to aluminum die casting, PPS, and the like.

<Ingredient (D)>
The component (D) of the present invention is a thermal cationic polymerization initiator, which is a compound that generates cationic species by heating. The type is not particularly limited, and examples thereof include an aromatic sulfonium-based thermal cationic polymerization initiator, an aromatic iodonium-based thermal cationic polymerization initiator, a thermal cationic polymerization initiator containing an amine salt, and the like, among which photocurable. A thermocationic polymerization initiator containing an amine salt is preferable from the viewpoint of obtaining a cationically curable composition having excellent adhesiveness to aluminum die cast, PPS and the like while maintaining low temperature curability. These may be used alone or in combination of two or more.

Examples of the thermal cationic polymerization initiator containing the amine salt include a thermal cationic polymerization initiator containing a salt having a quaternary ammonium cation. More specific salts having a quaternary ammonium cation include a salt composed of a quaternary ammonium cation and a borate anion, a salt composed of a quaternary ammonium cation and an antimony anion, and a salt composed of a quaternary ammonium cation and a phosphate anion. Can be mentioned. Among these, a salt composed of a quaternary ammonium cation and a borate anion or a salt composed of a quaternary ammonium cation and an antimony anion is preferable because it has excellent adhesion to aluminum die cast, PPS and the like.

Examples of the borate anion include tetrafluoroborate anion and tetrakis (perfluorophenyl) borate anion. Examples of the antimony anion include tetrafluoroantimony anion and tetrakis (perfluorophenyl) antimony anion. Examples of the phosphate anion include hexafluorophosphate anion and trifluoro [tris (perfluoroethyl)].

Commercially available products of the thermal cation polymerization initiator containing the amine salt include, for example, a salt composed of K-PURE (registered trademark, the same applies hereinafter) CXC-1612 (manufactured by King Industries, Inc., quaternary ammonium cation and borate anion). Thermal cationic polymerization initiator), K-PURE CXC-1821 (manufactured by King Industries, Inc., a thermal cationic polymerization initiator containing a salt composed of a quaternary ammonium cation and an antimony anion) and the like.

Commercially available products of the aromatic sulfonium-based thermal cationic polymerization initiator include Sun Aid (registered trademark, the same applies hereinafter) SI-60, Sun Aid SI-60L, Sun Aid SI-80, Sun Aid SI-80L, Sun Aid SI-100, and Sun Aid SI. -100L, Sun Aid SI-180L, Sun Aid SI-B2A, Sun Aid SI-B3A (all manufactured by Sanshin Chemical Industry Co., Ltd.), CI-2624 (manufactured by Nippon Soda Co., Ltd.) and the like. Examples of the aromatic iodonium-based thermal cationic polymerization initiator include diphenyliodonium trifluoromethanesulfonate (reagent).

The blending amount of the component (D) in the cationically curable composition of the present invention is not particularly limited, but is 0.1 to 30 mass by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). It is preferably in the range of parts, more preferably in the range of 0.5 to 15 parts by mass. When the blending amount of the component (D) is 0.1 part by mass or more with respect to 100 parts by mass of the total amount of the component (A) and the component (B), sufficient low temperature curability can be obtained, and 30 When it is less than a part by mass, it is preferable from the viewpoint of excellent adhesion to aluminum die casting, PPS and the like.

<Ingredient (E)>
The component (E) of the present invention is not particularly limited as long as it is a polycaprolactone polyol having a trifunctional or higher functional hydroxyl group and a molecular weight of 1700 or less. The component (E) of the present invention can be combined with other components of the present invention and can be combined with aluminum die-cast, PPS, etc. while maintaining photocurability and low-temperature curability by setting the compounding range to be described later. It can have a remarkable effect of being excellent in adhesiveness. The molecular weight of the component (E) is more preferably in the range of 200 to 1500, and particularly preferably in the range of 250 to 1000. The molecular weight is measured by measuring the hydroxyl value of the polycaprolactone polyol measured according to JIS K1557-1: 2007.

The component (E) is not particularly limited, and examples thereof include compounds represented by the following general formula (2).

Specific examples of the compound of the component (E) include polycaprolactone triol and polycaprolactone tetraol. Examples of commercially available products of the component (E) include Praxel (registered trademark, the same applies hereinafter) 303, Praxel 305, Praxel 308, Praxel 309, Praxel 312, and Praxel 400 (manufactured by Daicel Corporation).

The cationically curable composition of the present invention is characterized by containing 12 to 100 parts by mass of the component (E) with respect to 100 parts by mass of the total amount of the component (A) and the component (B), preferably 15. It is about 70 parts by mass, more preferably 17 to 50 parts by mass. Within the above range, a cationically curable composition having excellent adhesiveness to aluminum die-cast, PPS, etc. can be obtained while maintaining photocurability and low-temperature curability.

<Arbitrary ingredient>
Further, the cationic curable composition of the present invention includes a silane coupling agent, a colorant, an oxetane compound, a vinyl ether compound, a sensitizer, a peroxide, a thiol compound, a storage stabilizer, etc., as long as the characteristics of the present invention are not impaired. The additive of the above may be blended in an appropriate amount. Further, the cationic curable composition of the present invention contains calcium carbonate, magnesium carbonate, titanium oxide, magnesium hydroxide, talc, silica, alumina, glass, aluminum hydroxide, boron nitride, as long as the characteristics of the present invention are not impaired. Inorganic fillers such as aluminum nitride and magnesium oxide having an average particle size of 0.001 to 100 μm; conductive particles such as silver; flame retardants; rubbers such as acrylic rubber and silicon rubber; plastics; organic solvents; phenolic oxidation Antioxidants such as antioxidants and phosphorus antioxidants; light stabilizers; UV absorbers; antifoaming agents; foaming agents; mold release agents; leveling agents; leology control agents; tackifiers; curing retarders; polyimide resins , Polyamide resins, phenoxy resins, cyanate esters, poly (meth) acrylate resins, polyurethane resins, polyurea resins, polyester resins, polyvinyl butyral resins, styrene-butadiene-styrene copolymers (SBS), styrene-ethylene An appropriate amount of a polymer such as a-butylene-styrene copolymer (SEBS) or various additives such as a thermoplastic elastomer may be blended. By these additions, a cationic curable composition having excellent resin strength, adhesive strength, flame retardancy, thermal conductivity, workability and the like and a cured product thereof can be obtained.

The silane coupling agent provides a cationically curable composition having excellent adhesiveness to aluminum die-cast, PPS, etc., while improving the compatibility of the components (A) to (E) and further improving the low temperature curability. It is a compound that can be used. The silane coupling agent is not particularly limited, but specifically, for example, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3 -Glysidyl group-containing silane coupling agent such as glycidoxypropylmethyldiethoxysilane, vinyl group-containing silane coupling agent such as vinyltris (β-methoxyethoxy) silane, vinyltriethoxysilane, vinyltrimethoxysilane, γ-methacry (Meta) acrylic group-containing silane coupling agent such as loxypropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-phenyl-γ-amino Examples thereof include amino group-containing silane coupling agents such as propyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, and γ-chloropropyltrimethoxysilane. Among these, a glycidyl group-containing silane coupling agent is preferably used, and among the glycidyl group-containing silane coupling agents, 3-glycidoxypropyltrimethoxysilane and 3-glycidoxypropyltriethoxysilane are preferable. These silane coupling agents may be used alone or in combination of two or more. The amount of the silane coupling agent to be blended is not particularly limited, but is preferably in the range of 0.1 to 30 parts by mass with respect to 100 parts by mass in total of the components (A) and (B). Yes, more preferably in the range of 0.5 to 15 parts by mass.

Examples of the colorant include pigments and dyes, but among them, pigments are preferable from the viewpoint of durability. Further, among the pigments, a black pigment is preferable from the viewpoint of excellent hiding power. Examples of the black pigment include carbon black, black titanium oxide, copper chrome black, cyanine black, aniline black and the like. Among these, carbon black is preferable from the viewpoint of concealment and dispersibility with respect to the component (A) of the present invention. The blending amount of the colorant in the cationically curable composition of the present invention is not particularly limited, but is in the range of 0.01 to 30 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B). It is preferably in the range of 0.05 to 10 parts by mass, more preferably in the range of 0.1 to 5 parts by mass.

Examples of the oxetane compound include 3-ethyl-3-hydroxymethyloxetane, 3- (meth) allyloxymethyl-3-ethyloxetane, (3-ethyl-3-oxetanylmethoxy) methylbenzene, and 4-fluoro- [1. -(3-Ethyl-3-oxetanylmethoxy) methyl] benzene, [1- (3-ethyl-3-oxetanylmethoxy) ethyl] phenyl ether, isobutoxymethyl (3-ethyl-3-oxetanylmethyl) ether, 2- Ethylhexyl (3-ethyl-3-oxetanylmethyl) ether, ethyldiethylene glycol (3-ethyl-3-oxetanylmethyl) ether, tetrahydrofurfuryl (3-ethyl-3-oxetanylmethyl) ether, tetrabromophenyl (3-ethyl-) 3-Oxetanylmethyl) ether, 2-tetrabromophenoxyethyl (3-ethyl-3-oxetanylmethyl) ether, pentachlorophenyl (3-ethyl-3-oxetanylmethyl) ether, pentabromophenyl (3-ethyl-3-oxetanyl) ether Methyl) ether, ethylene glycol bis (3-ethyl-3-oxetanyl methyl) ether, triethylene glycol bis (3-ethyl-3-oxetanyl methyl) ether, tetraethylene glycol bis (3-ethyl-3-oxetanyl methyl) ether , Trimethylol propanthryl (3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tris (3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tetrakis (3-ethyl-3-oxetanylmethyl) ether, dipentaerythritol Examples thereof include tetrax (3-ethyl-3-oxetanylmethyl) ether and ditrimethylolpropane tetrax (3-ethyl-3-oxetanylmethyl) ether. Examples of commercially available oxetane compounds include Aron Oxetane (registered trademark, the same applies hereinafter) OXT-212, Aron Oxetane OXT-221, Aron Oxetane OXT-213, and Aron Oxetane OXT-101 (manufactured by Toagosei Co., Ltd.). Be done.

Examples of the vinyl ether compound include 1,4-butanediol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, tetraethylene glycol divinyl ether, normal propyl vinyl ether, isopropyl vinyl ether, normal butyl vinyl ether, isobutyl vinyl ether, and 2-ethylhexyl. Examples thereof include vinyl ether, cyclohexyl vinyl ether, 2-hydroxyethyl vinyl ether, diethylene glycol monovinyl ether, 4-hydroxybutyl vinyl ether, 2- (2-vinyloxyethoxy) ethyl acrylate, 2- (2-vinyloxyethoxy) ethyl methacrylate and the like. .. Commercially available products of vinyl ether compounds include, for example, NPVE, IPVE, NBVE, IBVE, 2-EHVE, CHVE (above, manufactured by Nippon Carbide Industries, Ltd.), HEVE, DEVGV, HBVE (above, manufactured by Maruzen Petrochemical Co., Ltd.), VEEA, VEEM (all manufactured by Nippon Shokubai Co., Ltd.) and the like can be mentioned.

Examples of the sensitizer include 9-fluorene, antron, dibenzosverone, fluorene, 2-bromofluorene, 9-bromofluorene, 9,9-dimethylfluorene, 2-fluorofluorene, 2-iodofluorene, and 2-fluorene. Amin, 9-fluoreneol, 2,7-dibromofluorene, 9-aminofluorene hydrochloride, 2,7-diaminofluorene, 9,9'-spirobie [9H-fluorene], 2-fluorene carboxylaldehyde, 9-fluoreneyl Methanol, 2-acetylfluorene, benzophenone, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2) -Propyl) ketone, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-2-morpholino (4-thiomethylphenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholino) Examples thereof include phenyl) butanone, 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propanone oligomer, nitro compound, and dye. The amount of the sensitizer added is not particularly limited, but may be appropriately determined with reference to the absorption wavelength and the molar extinction coefficient.

<Curing method>
The cationically curable composition of the present invention can be cured by irradiation with active energy rays (photocurable). In addition, the cationically curable composition of the present invention can be cured under low temperature conditions (low temperature curability). Furthermore, the cationically curable composition of the present invention can be cured under irradiation with active energy rays and low temperature conditions. Here, examples of the active energy ray include ultraviolet rays, electron beams, visible rays, and the like. The wavelength of the active energy ray is preferably 150 to 830 nm, more preferably 200 to 600 nm, and even more preferably 250 to 380 nm.

Further, the above-mentioned "low temperature" means that the curable temperature of the cationically curable composition of the present invention is low, and actually corresponds to the heating conditions of the curing method of the cationically curable composition of the present invention. The heating conditions (curable temperature) are not particularly limited, but are, for example, 45 ° C. to 150 ° C., preferably 45 ° C. or higher and lower than 150 ° C., more preferably 50 ° C. or higher and lower than 140 ° C., and 55 ° C. It is more preferable that the temperature is at least 130 ° C. In the case of a heat curing temperature of 45 ° C. or higher and lower than 150 ° C., the heating time is preferably in the range of 3 minutes or more and less than 5 hours, and more preferably in the range of 10 minutes or more and 3 hours or less. Further, the cationic curable composition of the present invention can be cured by irradiation with active energy rays. Examples of the active energy ray in this case include ultraviolet rays, electron beams, visible rays, and the like, but are not particularly limited. Integrated light quantity of the active energy ray is, for example, 300 ~ 100000mJ / cm ^2, preferably 500 ~ 50000mJ / cm ^2, more preferably 1000 ~ 10000mJ / cm ^2, more preferably 2000 ~ 5000mJ / cm ^2, particularly preferably It is 3000 mJ / cm ² . The wavelength of the active energy ray is preferably 150 to 830 nm, more preferably 200 to 600 nm, and even more preferably 250 to 380 nm.

<Adhesion method>
The cationically curable composition of the present invention can be used for adhesion of an adherend. Specific bonding methods include, for example, a step 1 of arranging the cationically curable composition of the present invention between a pair of adherends and a step 2 of irradiating the cationically curable composition with active energy rays. The method of adhering the adherend, which comprises the step 3 of heating at a temperature of 45 ° C. or higher and lower than 150 ° C. after the irradiation. Hereinafter, each step will be described.

[Step 1]
The cationically curable composition of the present invention is placed between a pair of adherends. Specifically, for example, the cationically curable composition is placed on one adherend by dropping or coating, and the other adherend is placed on the arranged cationically curable composition, and optionally. The pair of adherends are aligned and positioned. For coating, for example, a coating method used with a known sealant or adhesive may be used. As a specific coating method, for example, methods such as dispensing, spraying, inkjet, screen printing, gravure printing, dipping, and spin coating using an automatic coating machine can be used. As the adherend, for example, metal, glass, plastic or the like can be used, but from the viewpoint of being compatible with the cationic curable composition of the present invention, aluminum die casting, PPS and the like are preferable.

[Step 2]
The cationically curable composition arranged in step 1 is irradiated with active energy rays, the curing of the cationically curable composition proceeds, and the pair of adherends are temporarily adhered. Curing of the cationically curable composition by irradiation with active energy rays proceeds particularly in the surface of the composition and its vicinity. Irradiation may be performed directly on the placed cationic curable composition, or indirectly via the adherend, especially if the adherend is transparent or translucent.

[Step 3]
After irradiation with the active energy rays in step 2, the placed cationic curable composition is further heated at a predetermined temperature, the cationic curable composition is completely cured, and the pair of adherends are completely adhered (main adhesion). ). Curing of the cationically curable composition by heating proceeds inside the composition, especially except on the surface of the composition and its vicinity. By performing the curing reaction by irradiation in step 2 before the curing reaction by heating in step 3, the curing (crosslinking) reaction of the resin composition is promptly started, and by the subsequent curing reaction by heating in step 3. The reaction inside the cationically curable composition that is not exposed to the active energy rays proceeds rapidly, and complete curing of the cationically curable composition can be achieved. The heating temperature in step 3 is preferably 45 ° C. to 150 ° C., more preferably 45 ° C. or higher and lower than 140 ° C., further preferably 50 ° C. or higher and lower than 130 ° C., and particularly preferably 55 ° C. or higher and lower than 125 ° C.

<Use of cationic curable composition>
The use of the cationically curable composition of the present invention is not particularly limited, and examples thereof include an adhesive, a sealing agent, a coating agent, a potting agent, and a conductive paste. The field to which the cationic curable composition of the present invention can be applied is not particularly limited, but is, for example, an automobile field such as a switch portion, a head lamp, an engine internal component, an electrical component, a drive engine, and a brake oil tank; a liquid crystal display. Flat panel display field such as display, organic electroluminescence, touch panel, plasma display, light emitting diode display device; recording field such as video disc, CD, DVD, MD, pickup lens, hard disk peripheral member, Blu-ray disc, etc .; electronic component, electric circuit Electronic material fields such as encapsulants for relays, electrical contacts or semiconductor elements, die-bonding agents, conductive adhesives, anisotropic conductive adhesives, interlayer adhesives for multilayer substrates including build-up substrates; CMOS image sensors Camera modules such as Li batteries, manganese batteries, alkaline batteries, nickel-based batteries, fuel cells, silicon-based solar cells, dye-sensitized solar cells, organic solar cells, etc. Battery fields; Peripheral optical switches in optical communication systems , Optical component fields such as optical fiber materials around optical connectors, optical passive parts, optical circuit parts, and peripherals of optical electron integrated circuits; mobile terminal devices; construction field; aviation field and the like.

The cationically curable composition of the present invention is excellent in adhesiveness to aluminum die-casting, PPS, etc. while maintaining photocurability and low-temperature curability. It can be particularly preferably used as an agent. Examples of the electronic / electrical component module include a display housing, a personal computer housing, an optical pickup module, a mobile device housing, an HDD housing, a camera module, a projector housing, a CD / DVD player housing, a heat sink, a relay, and a connector. A module case or the like can be mentioned. Examples of the in-vehicle parts include an ECU case, an in-vehicle camera module, an in-vehicle sensor module (in-vehicle radar module, an in-vehicle lidar module, etc.), a capacitor case, a power module, a connector, an ignition coil, and the like.

The present invention will be specifically described below with reference to Examples, but the present invention is not limited by the following Examples.

<Preparation of cationic curable composition>
・ Example 1
As a component (A), 20 parts by mass of aromatic bisphenol F type epoxy resin (a1) (manufactured by Mitsubishi Chemical Corporation, jER807ST),
As components (B), 50 parts by mass of hydrogenated bisphenol A type epoxy resin (b1) (manufactured by Mitsubishi Chemical Corporation, jER YX-8000), and 3', 4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate. (B2) (manufactured by Daicel Co., Ltd., Celoxide 2021P) 30 parts by mass and
As a component (C), 3 parts by mass of 4-methylphenyl-4- (1-methylethyl) phenyliodonium-tetrakis (pentafluorophenyl) borate (c1) (Rodia, Bluesil PI-2074),
2 parts by mass of a thermal cationic polymerization initiator (d1) (K-PURE CXC-1821 manufactured by King Industries, Inc.) containing a salt composed of a quaternary ammonium cation and a borate anion as a component (D).
25 parts by mass of polycaprolactone triol (e1) (manufactured by Daicel Corporation, Praxel 305) having a trifunctional hydroxyl group and a molecular weight of 550 as a component (E).
As a silane coupling agent, 2 parts by mass of 3-glycidoxypropyltrimethoxysilane and
Was added and mixed with a planetary mixer at room temperature (25 ° C.) for 60 minutes under shading to obtain the cationic curable composition of Example 1.

-Example 2
Example 1 except that (a1) component 20 parts by mass was changed to 50 parts by mass, (b1) component was not used, and (b2) component 30 parts by mass was changed to 50 parts by mass in Example 1. The same preparation as in the above was performed to obtain a cationic curable composition of Example 2.

・ Example 3
In Example 1, 50 parts by mass of the component (b1) was changed to 80 parts by mass, and the preparation was carried out in the same manner as in Example 1 except that the component (b2) was not used. I got something.

・ Comparative example 1
In Example 1, the cation-curable composition of Comparative Example 1 was obtained by preparing in the same manner as in Example 1 except that the component (a1) was removed and 50 parts by mass of (b1) was changed to 70 parts by mass. It was.

・ Comparative example 2
A cationic curable composition of Comparative Example 2 was obtained by preparing in the same manner as in Example 1 except that the component (e1) was removed in Example 1.

・ Comparative example 3
A cationic curable composition of Comparative Example 3 was obtained by preparing in the same manner as in Example 1 except that 25 parts by mass of the component (e1) was changed to 10 parts by mass in Example 1.

・ Comparative example 4
Example 1 except that the component (e1) was changed to a polycaprolactone polyol (e'1) (manufactured by Daicel Corporation, Praxel 205) having a bifunctional hydroxyl group and a molecular weight of 500. The same preparation as in the above was performed to obtain a cationically curable composition of Comparative Example 4.

・ Comparative example 5
Example 1 except that the component (e1) was changed to a polycaprolactone polyol (e'2) (manufactured by Daicel Corporation, Praxel 320) having a trifunctional hydroxyl group and a molecular weight of 2000. The same preparation as in the above was performed to obtain a cationically curable composition of Comparative Example 5.

-Comparative example 6
A cationic curable composition of Comparative Example 6 was obtained by preparing in the same manner as in Example 1 except that the component (d1) was removed in Example 1.

<Photocurability test>
0.01 g of the cationic curable composition was added dropwise onto a glass test piece having a width of 25 mm, a length of 100 mm, and a thickness of 5 mm. Then, an ultraviolet irradiation device (manufactured by Jatec Co., Ltd., model number: JUL-M-433AN-05, ultraviolet wavelength: 365 nm) was used to irradiate an active energy ray with an ^{integrated light amount of 3000 mJ / cm 2 to obtain a test piece.} Next, a glass rod having a sharp tip was brought into contact with the test piece, and the curability of the cationically curable composition was evaluated based on the following criteria. If it is ○ in the following criteria, it can be said that the curability is good.

[Evaluation criteria]
◯: There is no deposit on the rod ×: There is deposit on the rod.

<Low temperature curability test>
0.1 g of each cationic curable composition was dropped onto a hot plate set at 100 ° C., and after 30 minutes, a glass rod having a sharp tip was brought into contact with the cured product, and the curability of the composition was determined according to the following criteria. Evaluated based on. If it is ○ in the following criteria, it can be said that the low temperature curability is good.

<Tension Shear Adhesive Strength Test for Aluminum Die Casting>
The cationic curable compositions of Examples and Comparative Examples were applied to a test piece made of aluminum die-cast ADC12 having a width of 25 mm, a length of 100 mm, and a thickness of 1 mm. Then, another aluminum die-cast ADC12 test piece was attached and fixed with a clip so that the overwrap surface was 25 mm × 10 mm. Then, it was cured in a hot air drying furnace set at 120 ° C. for 60 minutes to obtain a test piece. Then, using the test piece, the tensile shear adhesion strength (unit: MPa) was measured at 25 ° C. with a universal tensile tester (tensile speed 50 mm / min.) According to JIS K6850: 1999. The tensile shear adhesive strength was taken as the value at the maximum strength. In order to use the cationically curable composition of the present invention as an adhesive for assembling electronic / electrical component modules, in-vehicle components, etc., the tensile shear adhesive strength is preferably 5.0 MPa or more.

<Tensile Shear Adhesive Strength Test for Polyphenylene Sulfide (PPS)>
The cationic curable compositions of Examples and Comparative Examples were applied to a PPS test piece having a width of 25 mm, a length of 100 mm, and a thickness of 1 mm. Then, another PPS test piece was attached and fixed with a clip so that the overwrap surface was 25 mm × 10 mm. Then, it was cured in a hot air drying furnace set at 120 ° C. for 60 minutes to obtain a test piece. Then, using the test piece, the tensile shear adhesion strength (unit: MPa) was measured at 25 ° C. with a universal tensile tester (tensile speed 50 mm / min.) According to JIS K6850: 1999. The tensile shear adhesive strength was taken as the value at the maximum strength. In order to use the cationically curable composition of the present invention as an adhesive for assembling electronic / electrical component modules, in-vehicle components, etc., the tensile shear adhesive strength is preferably 5.0 MPa or more.

The above test results are summarized in Table 1 below. In addition, "-" in Table 1 below indicates that the measurement was not performed.

As is clear from Table 1 above, it was found that the cationic curable compositions of Examples 1 to 3 are excellent in adhesiveness to aluminum die casting, PPS, etc. while maintaining photocurability and low temperature curability. It was.

Comparative Example 1 is a cationically curable composition containing no component (A) of the present invention, but it was found that the adhesiveness to PPS was inferior. Further, Comparative Example 2 was a cationically curable composition containing no component (E) of the present invention, but it was found that the adhesiveness to aluminum die casting and PPS was inferior. Further, Comparative Example 3 was a cationically curable composition in the case of an addition amount outside the predetermined range of the component (E) of the present invention, but it was found that the adhesiveness to aluminum die casting and PPS was inferior. Further, Comparative Examples 4 and 5 were cationically curable compositions when a polyol not the component (E) of the present invention was used, but it was found that the adhesiveness to aluminum die casting was inferior. Comparative Example 6 was a cationically curable composition containing no component (D) of the present invention, but the results were inferior in the low temperature curability test.

The cationically curable composition of the present invention is excellent in adhesiveness to aluminum die-casting, PPS, etc. while maintaining photocurability and low-temperature curability. , It is industrially useful because it can be applied to a wide range of fields.

This application is based on Japanese Patent Application No. 2019-223752 filed on December 11, 2019, the entire disclosure of which is incorporated herein by reference in its entirety.

Claims

A cationic curable composition containing the following components (A) to (E) and containing 12 to 100 parts by mass of the component (E) with respect to 100 parts by mass of the total amount of the components (A) and (B). :
Component (A): Aromatic epoxy resin (B) Component: At least one of hydride epoxy resin (B1) and alicyclic epoxy resin (B2) (C) Component: Photocationic polymerization initiator (D) Component: Thermal cation Polymerization initiator (E) component: A polycaprolactone polyol having a trifunctional or higher functional hydroxyl group and having a molecular weight of 1700 or less.
The cationic curable composition according to claim 1, wherein the component (B) is contained in an amount of 10 to 80 parts by mass with respect to 100 parts by mass of the total amount of the component (A) and the component (B).
The component (D) is at least one selected from the group consisting of an aromatic sulfonium-based thermal cationic polymerization initiator, an aromatic iodonium-based thermal cationic polymerization initiator, and a thermal cationic polymerization initiator containing an amine salt. The cationically curable composition according to claim 1 or 2.
The cationic curable composition according to any one of claims 1 to 3, wherein the component (D) is a thermal cationic polymerization initiator containing a salt having a quaternary ammonium cation.
The cationic curable composition according to any one of claims 1 to 4, wherein the component (C) contains at least one of an aromatic iodonium salt and an aromatic sulfonium salt.
Claims 1 to 5, wherein the component (A) contains at least one selected from the group consisting of an aromatic bisphenol A type epoxy resin, an aromatic bisphenol F type epoxy resin, and an aromatic bisphenol E type epoxy resin. The cationic curable composition according to any one of the following items.
The cationic curable composition according to any one of claims 1 to 6, wherein the component (B) contains only one of the hydrogenated epoxy resin (B1) and the alicyclic epoxy resin (B2). Stuff.
The cationic curable composition according to any one of claims 1 to 6, wherein the component (B) contains the hydrogenated epoxy resin (B1) and the alicyclic epoxy resin (B2).
The cationically curable composition according to any one of claims 1 to 8, which is used as an adhesive.
The cationically curable composition according to any one of claims 1 to 9, which is used for an adhesive whose adherend is aluminum die-cast or PPS.
A cured product of the cationically curable composition according to any one of claims 1 to 10.
A bonded body obtained by adhering an adherend using the cationically curable composition according to any one of claims 1 to 10.