Thermosetting resin composition for microwave irradiation, and method for manufacturing composite structure

Abstract

To provide a thermosetting resin composition which is thermoset by irradiation with microwaves in a short time, and can bond much precise / small-sized members having low heat resistance once, and a method for manufacturing a composite structure which is composed of a precise / small-sized member using the thermosetting resin composition.SOLUTION: (1) A thermosetting resin composition for microwave irradiation contains a cyclic ether compound and a polymerization initiator, wherein the polymerization initiator is a thermal cationic polymerization initiator, and one or more members selected from the group consisting of a circuit connection member, an electronic / electric member, an optical member, a construction member, and an automobile member are bonded between the members or to other member under irradiation with microwaves. (2) A thermosetting resin composition for microwave irradiation contains a cyclic ether compound and a polymerization initiator, wherein the polymerization initiator is an iodonium-based photocationic polymerization initiator and a radical polymerization initiator.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a thermosetting resin composition for microwave irradiation that is thermally cured under microwave irradiation, and a method for producing a composite structure in which members are bonded together with the thermosetting resin composition for microwave irradiation. [Background technology]

[0002] Precision and small components such as display panels, touch panels, sensors, lenses, battery components, and semiconductor components, as well as components such as housings that house these precision and small components, may be bonded with a curable resin composition (hereinafter also referred to as "adhesive") in the process of manufacturing composites into which these components are incorporated, such as video and image display devices, imaging devices, communication devices, household electrical appliances, batteries, and integrated circuits (hereinafter the process of bonding the above components with an adhesive will also be referred to as the "bonding process").

[0003] In the bonding process when producing the above-mentioned composite, a photocurable adhesive that cures with short-term light irradiation is used, and the adhesive applied to the components is mainly irradiated with light for each component or each bonded portion to cure the adhesive (for example, Patent Documents 1 and 2).

[0004] In the step of irradiating the photocurable adhesive with light, the photocurable adhesive hardens with light irradiation in a matter of seconds, and light can be irradiated for each member or each adhesive portion, so there is no need to secure a large space for light irradiation.

[0005] On the other hand, thermosetting adhesives are also used as adhesives in the bonding process. However, if a thermosetting adhesive requires more than several tens of minutes to cure by heating at around 100°C or higher, a large heating space must be secured. Therefore, it is used to bond heat-resistant precision and small components, while if it cures in several tens of minutes to several hours at room temperature, it is widely used in paint applications, civil engineering and construction applications, etc. (e.g., Patent Documents 3 and 4). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-144641 [Patent Document 2] International Publication No. 2011 / 001911 [Patent Document 3] Japanese Patent Application Publication No. 6-345726 [Patent Document 4] International Publication No. 2021 / 241129 Summary of the Invention [Problem to be solved by the invention]

[0007] As described above, conventional photocurable adhesives and thermosetting adhesives have many advantages, but also have the following problems.

[0008] Conventional light-curing adhesives are suitable for bonding small, precise components because they can be light-cured individually in a small light-irradiated space in a short time without generating high temperatures. However, there is a problem in that bonding becomes unstable in areas where light is difficult to reach, making it impossible to bond many small, precise components at once.

[0009] Conventional thermosetting adhesives require tens of minutes or more to harden when heated to around 100°C or higher, and require a large heating space, so they are rarely used to bond precision and small components with low heat resistance.

[0010] The present invention aims to provide a thermosetting resin composition that can be thermally cured in a short time by microwave irradiation and can bond many small, precision components with low heat resistance at once, and a method for manufacturing a composite structure made of small, precision components using the thermosetting resin composition. [Means for solving the problem]

[0011] The present invention provides [1] A thermosetting resin composition comprising a cyclic ether compound (compound A) and a polymerization initiator, the polymerization initiator is a thermal cationic polymerization initiator (compound B1), A thermosetting resin composition for bonding one or more members selected from the group consisting of circuit connecting members, electronic / electrical members, optical members, architectural members, and automotive members to each other or to other members under microwave irradiation (hereinafter also referred to as "present invention 1"); [2] A thermosetting resin composition for microwave irradiation, comprising a cyclic ether compound (compound A) and a polymerization initiator, a thermosetting resin composition for microwave irradiation, wherein the polymerization initiator is an iodonium-based cationic photopolymerization initiator (compound B2) and a radical polymerization initiator (compound C) (hereinafter also referred to as "present invention 2"); [3] A method for manufacturing a composite structure including the member according to the preceding paragraph [1], Step 1 of applying the thermosetting resin composition according to the above item [1] to any of the members; and step 2 of irradiating the thermosetting resin composition with microwaves to thermally cure it. A method for manufacturing a composite structure (hereinafter also referred to as "present invention 3"), and [4] A method for manufacturing a composite structure including a member 1 and a member 2, A step A of bonding the member 1 and the member 2 together via the thermosetting resin composition described in the preceding item [2]; and step B of irradiating the thermosetting resin composition with microwaves to thermally cure it. The present invention relates to a method for manufacturing a composite structure (hereinafter also referred to as "present invention 4").

[0012] Hereinafter, Inventions 1 to 4 will also be collectively referred to as "the present invention." [Effects of the Invention]

[0013] According to the present invention, there are provided a thermosetting resin composition that is heat-cured in a short time by microwave irradiation and can bond many small, precision components with low heat resistance at once, and a method for manufacturing a composite structure composed of small, precision components using the thermosetting resin composition. DETAILED DESCRIPTION OF THE INVENTION

[0014] <<Invention 1 and Invention 2>>

[0015] Invention 1 is a thermosetting resin composition containing a cyclic ether compound (compound A) and a polymerization initiator, the polymerization initiator is a thermal cationic polymerization initiator (compound B1), A thermosetting resin composition for bonding one or more components selected from the group consisting of circuit connection components, electronic / electrical components, optical components, architectural components, and automotive components to each other or to other components under microwave irradiation.

[0016] Invention 2 is a thermosetting resin composition for microwave irradiation, comprising a cyclic ether compound (compound A) and a polymerization initiator, The thermosetting resin composition for microwave irradiation is such that the polymerization initiator is an iodonium-based cationic photopolymerization initiator (compound B2) and a radical polymerization initiator (compound C).

[0017] <<Use of Invention 1 and Invention 2>> Invention 1 and Invention 2 harden in a few minutes with little heat generation when irradiated with microwaves, making it possible to bond components in places where light cannot easily reach with conventional light irradiation, and it is possible to bond many precision and small components with low heat resistance at once, so they can be used in the following applications.

[0018] In addition, when the member to which Invention 1 and Invention 2 are applied contains a metal that easily generates heat when irradiated with microwaves or is adjacent to a metal member that easily generates heat when irradiated with microwaves, from the viewpoint of preventing the metal or metal member from being overheated and damaged by microwave irradiation, Replace the metal with a material that does not easily generate heat when irradiated with microwaves. The metal is removed from the component to which Invention 1 and Invention 2 are applied, or For example, microwave irradiation is performed before the metal is attached to the component. It is preferable that the target member to be irradiated with microwaves does not contain a metal that easily generates heat when irradiated with microwaves, or is not adjacent to a metal member that easily generates heat when irradiated with microwaves.

[0019] Below, we will explain in detail the joining of injection-molded plastic molded components as a typical use or application of Invention 1 and Invention 2, but the explanation will also be applicable if the injection-molded plastic molded components are replaced with ceramic components such as glass.

[0020] [Joining of injection molded plastic components] When joining multiple injection-molded plastic molded components in post-processing, present invention 1 or 2 can be applied to the joints of each component, the components can be joined, and then present invention 1 or 2 applied to the joints can be thermally cured under microwave irradiation, thereby achieving stable joining in a short period of time.

[0021] For example, the following joining modes can be exemplified, and in these joining modes, a plurality of plastic molded components that have been injection molded are often joined in post-processing.

[0022] Joining of device and housing components together or between housing components and decorative components, such as joining of camera body housing components together or between housing components and decorative components, joining of mobile phone housing components, joining of display backlight units and housings, joining of white goods such as refrigerators and washing machines, joining of plastic housings and decorative components for building or automotive parts; Joining the barrel and lens of an interchangeable lens; Joining of mobile phone housing components; Joining prisms to plastic or ceramic components in optical communication equipment; Bonding of a color filter to a film or glass substrate.

[0023] The above-mentioned bonding step is preferably carried out before incorporating a metal member that is likely to generate heat when irradiated with microwaves.

[0024] [Production of a bonded lens constituting an optical display device]

[0025] (1) The present invention 1 and the present invention 2 can be suitably applied to the production of laminated lenses used in optical camera lenses, VR and AR lenses, projectors, etc.

[0026] For example, a method for producing a laminated plastic lens in which a plastic lens 1, a thermosetting product of the thermosetting resin composition of the present invention 1 or 2, and a plastic lens 2 are laminated together, comprising the steps of: Step 1 of bonding a plastic lens 1 and a plastic lens 2 together via the thermosetting resin composition of invention 1 or 2; and step 2 of thermally curing the thermosetting resin composition of invention 1 or 2 in step 1 under microwave irradiation to form a thermoset product of the thermosetting resin composition of invention 1 or 2 (note that plastic lens 1 and / or plastic lens 2 may be replaced with glass lens 1 and / or glass lens 2).

[0027] The thermosetting product of the thermosetting resin composition is The tensile modulus at 25°C is 0.1 MPa or more and 1000 MPa or less, The haze value at 25°C is 1.0 or less, The refractive index at 25°C is preferably 1.50 or more.

[0028] The plastic or glass lens is preferably transparent and has a high refractive index. For example, for plastic or glass lenses, The haze value is preferably 1.0% or less, more preferably 0.5% or less, and even more preferably 0.1% or less. The refractive index is preferably 1.50 or more, more preferably 1.60 or more, even more preferably 1.70 or more, and even more preferably 1.80 or more.

[0029] The haze value is measured based on JIS K7136.

[0030] The refractive index is measured at 25° C. for light with a wavelength of 589 nm using a prism coupler (Metricon, 2010 / M).

[0031] Resins that constitute transparent, high-refractive-index plastic lenses include (meth)acrylic resins, styrene resins, polycarbonate resins, polyolefin resins, polyethylene terephthalate resins, and polyoxyalkylene resins, and these resins continue to be improved. From the viewpoints of transparency and high refractive index, however, (meth)acrylic resins, polycarbonate resins, and polyolefin resins are preferred, and (meth)acrylic resins are more preferred.

[0032] The diameter of a plastic or glass lens (the diameter of the circle with the area of ​​the plastic lens when viewed from above) is: For applications such as in-vehicle rear / front cameras and surveillance cameras, small diameters (preferably more than 2 mm and less than 30 mm, more preferably 3 to 20 mm, and even more preferably 5 to 10 mm) are common. For applications such as optical camera lenses, VR and AR lenses, and projectors, large diameter lenses (preferably 30 to 150 mm, more preferably 40 to 100 mm, and even more preferably 50 to 80 mm) are often used.

[0033] (2) With the diversification of imaging technology, in the manufacture of optical display devices (hereinafter also referred to as 3D display devices) that display three-dimensional images (so-called 3D images) or three-dimensional images (so-called 3D images), the present invention 1 and the present invention 2 can be used to bond optical component parts such as a display body, a protective panel, and a touch panel.

[0034] When conventional light-curing adhesives are used, poor curing can be an issue in the light-shielding printing of the protective panel, the flexibility and wiring of the touch panel, and the light-shielding areas of the display panel, such as the wiring, black matrix, and optical film. However, by using Inventions 1 and 2, the light-shielding and light-shielded areas can be bonded equally well in a short time without generating high temperatures or damaging the components of these optical display devices.

[0035] [Other examples] (1) The present invention 1 and the present invention 2 can be suitably applied to, for example, bonding housing members of a camera body together or to decorative parts, or fixing a lens to a barrel of an interchangeable lens.

[0036] When conventional light-curing adhesives are used, for example, when the adhesive is sandwiched between a colored housing and a decorative part, or when a lens is attached to the inside of a barrel, it is not possible to sufficiently expose the light to the shading area, which can result in poor curing. However, by using Invention 1 and Invention 2 and irradiating microwaves, the shading part and the shading part can be bonded equally well in a short time without generating high heat or damaging these components.

[0037] (2) Invention 1 and Invention 2 are suitably applicable to, for example, bonding of housing members of a mobile phone, fixing of a display backlight unit to a housing, and bonding of a color filter to a film or glass substrate.

[0038] When conventional light-curing adhesives are used, for example, they can become sandwiched between the plastic molded parts that are joined to the housing, or the light can be blocked by the backlight unit and housing, or the light can be absorbed by the color filter, preventing sufficient light from being irradiated, resulting in poor curing.However, by irradiating microwaves with Inventions 1 and 2, the light-shielding part and the light-shielded part can be bonded equally well in a short time without generating high temperatures or damaging these components.

[0039] (3) The present invention 1 and the present invention 2 can be suitably applied to, for example, fixing decorative members or packings to plastic casings of white goods such as refrigerators and washing machines, or building or automobile parts, or bonding building members to each other or to decorative paper or decorative film.

[0040] When conventional light-curing adhesives are used, if the housing, decorative parts, packing, etc. are colored parts, light irradiation can result in insufficient curing because the light does not penetrate sufficiently to the parts that come into contact with or are sandwiched between the colored parts. However, by using present invention 1 and present invention 2 and irradiating microwaves, it is possible to bond the colored parts to the parts that come into contact with or are sandwiched between them in a short period of time without generating high temperatures or damaging these components.

[0041] [Compound A] Compound A is a cyclic ether compound, and from the viewpoints of the thermal curing rate under microwave irradiation and the strength of the thermoset product of invention 1 and invention 2, the following embodiments are preferred.

[0042] Examples of the cyclic ether compound include: Monofunctional epoxy resins such as n-butyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, and 1,2-epoxycyclohexane; Bifunctional epoxy resins such as hexanediol diglycidyl ether, tetraethylene glycol diglycidyl ether, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, monoallyl diglycidyl isocyanurate, and glycidyl methacrylate; Multifunctional epoxy resins such as trimethylolpropane triglycidyl ether, sorbitol polyglycidyl ether, 1,3-bis(N,N-diglycidylaminoethyl)benzene, novolac-type epoxy resins, and tetrakisphenolethane-type epoxy resins; Epoxy resins having an alicyclic oxirane ring, such as 1,2-epoxy-4-vinylcyclohexane, 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and 3,4-epoxycyclohexylmethyl methacrylate; monofunctional oxetane resins such as 3-ethyl-3-hydroxymethyloxetane, 3-ethyl-3-phenoxymethyloxetane, 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane, 3-ethyl(triethoxysilylpropoxymethyl)oxetane, and 3-cyclohexyloxymethyl-3-ethyloxetane; bifunctional oxetane resins such as bis(3-ethyl-3-oxetanylmethyl)ether and 1,4-bis{[(3-ethyl-3-oxetanyl)methoxy]methyl}benzene; Examples of suitable oxetane resins include polyfunctional oxetane resins such as trimethylolpropane tris(3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tris(3-ethyl-3-oxetanylmethyl) ether, pentaerythritol tetrakis(3-ethyl-3-oxetanylmethyl) ether, and dipentaerythritol pentakis(3-ethyl-3-oxetanylmethyl) ether; and tetrahydrofuran and dioxane.

[0043] [Compound B1] Compound B1 is a thermal cationic polymerization initiator, which is a component that serves as a cation generation source when cationic polymerization is performed by heating. From the viewpoints of the thermal curing rate under microwave irradiation and the strength of the thermoset product of invention 1, the following embodiment is preferred.

[0044] Examples of thermal cationic polymerization initiators include: the cation moiety is an aromatic sulfonium, aromatic diazonium, aromatic ammonium, thianthrhenium, thioxanthonium, or (2,4-cyclopentadien-1-yl)[(1-methylethylbenzene]-Fe cation; The anion part is SbF6 - , BF4 - , PF6 - , B(C6F5)4 - , [P(R F ) n F 6-n ] - (In the formula, R F are independently a partially or fully fluorinated alkyl group having 1 to 6 carbon atoms, and n is an integer of 0 to 5), or [BX4]- (wherein X is a phenyl group substituted with at least two fluorine atoms or trifluoromethyl groups), Examples include onium salts that are composed of a cationic portion and an anionic portion.

[0045] The thermal cationic polymerization initiator is preferably a sulfonium salt.

[0046] The anion of the thermal cationic polymerization initiator is SbF6 - , B(C6F5)4 - , or [P(R F ) n F 6-n ] - (In the formula, R F are preferably independently a partially or fully fluorinated alkyl group having 1 to 6 carbon atoms, and n is an integer of 0 to 5).

[0047] Commercially available thermal cationic polymerization initiators include: San-Apro's TA-60, TA-60B, TA-100, and TA-120; ADEKA's ADEKA Opton CP-77 and ADEKA Opton CP-66; CI-2639, CI-2624 manufactured by Nippon Soda Co., Ltd.; King Industries CXC-1612, CXC-1738; Examples include San-Aid SI-45, San-Aid SI-60, San-Aid SI-80, San-Aid SI-100, San-Aid SI-110, San-Aid SI-B3, San-Aid SI-B3A, and San-Aid SI-B4 manufactured by Sanshin Chemical Industry Co., Ltd.

[0048] The thermal cationic polymerization initiator may be one type or a combination of two or more types.

[0049] [Compound B2] Compound B2 is an iodonium-based cationic photopolymerization initiator capable of generating a substance that initiates cationic polymerization upon light irradiation, and from the viewpoints of the thermal curing rate under microwave irradiation and the strength of the thermoset product of present invention 2, the following embodiment is preferred.

[0050] Compound B2 includes an iodonium compound, and such a compound is preferably an iodonium salt that generates a Bronsted acid upon irradiation with light.

[0051] The iodonium salt of a Bronsted acid has an aromatic iodonium cation moiety. The anion part is BF4 - , PF6 - , SbF6 - , [BX4] - (X represents a phenyl group substituted with at least two fluorine or trifluoromethyl groups), [PF n Y 6-n ] - (Y represents a fluorinated alkyl group or a fluorinated phenyl group having 1 to 9 carbon atoms, and n is an integer of 1 to 6), and the anion moiety is selected from PF6 - , PF n Y 6-n ] - is preferred, [PF n Y 6-n ] - is more preferred.

[0052] Specific examples include diphenyliodonium salt of phosphorus hexafluoride, diphenyliodonium salt of antimony hexafluoride, and diphenyliodonium salt of tetrakis(pentafluorophenyl)boron.

[0053] Examples of commercially available products include PI2074 (manufactured by Solvay (Rhodia)), CD-1012 (product name, manufactured by SARTOMER), WPI-113, WPI-116, WPI-170, WPI-124 (all manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.), IK-1, IK-1FG (all manufactured by San-Apro Co., Ltd.), and the like.

[0054] The iodonium-based cationic photopolymerization initiators can be used alone or in combination of two or more.

[0055] [Compound C] Compound C is a radical polymerization initiator, and from the viewpoint of the thermal curing rate under microwave irradiation and the strength of the thermoset product of invention 2, the following embodiments are preferred.

[0056] Examples of the thermal radical polymerization initiator include ionic catalysts such as imidazoles, tertiary amines, quaternary ammonium salts, boron trifluoride amine complexes, organophosphines, and organophosphonium salts; organic peroxides such as diallyl peroxide, dialkyl peroxide, peroxide carbonate, and hydroperoxide; and azo compounds.

[0057] [Optional ingredients] (1) Solvent From the viewpoint of improving miscibility with compound A, compound B1, compound B2 and compound C may be dissolved in a solvent in advance, if necessary.

[0058] The solvents include propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monomethyl ether acetate, ethyl lactate, methyl methoxypropionate, cyclopentanone, cyclohexanone, γ-butyrolactone, diisoamyl ether, butyl acetate, isoamyl acetate, isopropanol, 4-methyl-2-pentanol, dimethyl sulfoxide, N-methylpyrrolidone, diethylene glycol, ethylene glycol, dipropylene glycol, propylene One or more solvents selected from the group consisting of glycol, ethylene carbonate, propylene carbonate, sulfolane, cycloheptanone, 2-heptanone, butyl butyrate, isobutyl isobutyrate, undecane, pentyl propionate, isopentyl propionate, ethylcyclohexane, mesitylene, decane, 3,7-dimethyl-3-octanol, 2-ethyl-1-hexanol, 1-octanol, 2-octanol, ethyl acetoacetate, dimethyl malonate, methyl pyruvate, and dimethyl oxalate are preferred, and γ-butyrolactone and propylene carbonate are more preferred.

[0059] (2) Other ingredients In the present invention 1 and the present invention 2, as needed, the following may be added within a range that does not impair the effects of the present invention: The composition may contain known additives such as inorganic fillers, reinforcing agents, colorants, stabilizers, extenders, viscosity modifiers, tackifiers, flame retardants, ultraviolet absorbers, antioxidants, discoloration inhibitors, antibacterial agents, antifungal agents, antiaging agents, antistatic agents, plasticizers, lubricants, leveling agents, foaming agents, and mold release agents.

[0060] [Formulation of the thermosetting composition of invention 1] From the viewpoint of the heat curing rate under microwave irradiation and the strength of the thermoset product of Invention 1, the heat curable composition of Invention 1 contains Compound B1 in an amount of: The amount is preferably 0.5 to 50 parts by weight, more preferably 1 to 40 parts by weight, even more preferably 2 to 30 parts by weight, even more preferably 3 to 20 parts by weight, even more preferably 4 to 10 parts by weight, and even more preferably 5 to 7 parts by weight.

[0061] In order to improve the miscibility with compound A, when compound B1 is mixed in advance with a solvent, The solvent is used in an amount of: The amount is preferably 10 to 300 parts by weight, more preferably 20 to 250 parts by weight, even more preferably 30 to 200 parts by weight, and still more preferably 40 to 150 parts by weight.

[0062] [Formulation of the thermosetting composition of invention 2] From the viewpoint of the heat curing rate under microwave irradiation and the strength of the thermoset product of the present invention 2, the total amount of compound B2 and compound C relative to 100 parts by weight of compound A is Preferably, it is 1 to 50 parts by weight, more preferably 2 to 40 parts by weight, even more preferably 3 to 30 parts by weight, even more preferably 4 to 20 parts by weight, and even more preferably 6 to 10 parts by weight. The blending weight ratio of compound B2 to compound C (compound B2 / compound C) is It is preferably 1 / 100 to 100 / 1, more preferably 10 / 90 to 90 / 10, even more preferably 20 / 80 to 80 / 20, even more preferably 30 / 70 to 70 / 30, even more preferably 35 / 65 to 65 / 35, and even more preferably 40 / 60 to 50 / 50.

[0063] In order to improve the miscibility with compound A, when compound B2 and compound C are mixed in advance with a solvent, the solvent is used in an amount of: The amount is preferably 10 to 300 parts by weight, more preferably 20 to 200 parts by weight, even more preferably 30 to 150 parts by weight, even more preferably 40 to 100 parts by weight, and even more preferably 50 to 70 parts by weight.

[0064] Invention 3 and Invention 4 Invention 3 is a method for producing a composite structure including the adherend of Invention 1, Step 1 of applying the present invention 1 to any of the above-mentioned members; and step 2 of irradiating the thermosetting resin composition with microwaves to thermally cure it. A method for manufacturing a composite structure.

[0065] Invention 4 is a method for manufacturing a composite structure including member 1 and member 2, a step A of bonding the member 1 and the member 2 via the present invention 2; and step B of irradiating the thermosetting resin composition with microwaves to thermally cure it. A method for manufacturing a composite structure.

[0066] (Application of thermosetting resin composition) In the present invention 3 and the present invention 4, the thermosetting resin composition of the present invention 1 or the present invention 2 is applied to one or both of the members to be bonded together.

[0067] The thermosetting resin composition of Invention 1 or Invention 2 may be applied to the entire surfaces to be bonded in a required thickness, or may be applied in a planar manner to a portion of the surfaces to be bonded, or may be applied in a spot manner. When corners of members are to be bonded, the composition may be applied in a line or spot manner along the corners of the members.

[0068] As an apparatus for applying the thermosetting resin composition of Invention 1 or Invention 2, for example, when applying in a planar form, various printing methods such as slit coating, spin coating, and screen coating can be used, and when applying in a spotted or linear form, various printing methods such as a dispenser and screen coating can be used.

[0069] (Microwave irradiation) A microwave irradiation device is used when members bonded together (hereinafter also referred to as "temporarily bonded") via the thermosetting resin composition of Invention 1 or Invention 2 are irradiated with microwaves to thermally cure the thermosetting resin composition of Invention 1 or Invention 2.

[0070] As a microwave irradiation device, for example, a microwave reaction vessel in which the temporarily bonded members are placed is placed inside a conductive storage vessel, and a microwave irradiation device in which multiple dipole antennas are evenly arranged to surround the microwave reaction vessel is used.

[0071] The temporarily bonded members may be continuously carried into a microwave irradiation device using a conveyor or the like, and the members bonded by microwave irradiation and heat curing of the thermosetting resin composition may be continuously carried out from the microwave irradiation device as is. Alternatively, multiple temporarily bonded members may be temporarily placed, and then the temporarily placed multiple temporarily bonded members may be carried into a microwave irradiation device, and the multiple temporarily bonded members may be irradiated with microwaves at once, and the bonded multiple members may be carried out from the microwave irradiation device. In this case, the larger the capacity of the irradiation device and the higher the irradiation power, the more preferable it is from the viewpoint that a large number of members can be bonded in a short time.

[0072] From the same viewpoint as above, the wavelength of microwaves is as follows: The wavelength is preferably 300 MHz to 300 GHz, more preferably 500 MHz to 100 GHz, even more preferably 700 MHz to 50 GHz, even more preferably 1 GHz to 10 GHz, and even more preferably 2 GHz to 5 GHz.

[0073] The microwave irradiation is preferably performed at 100 to 8000 W, more preferably 300 to 6000 W, and even more preferably 500 to 5000 W at the above-mentioned suitable wavelength. The irradiation time is preferably 1 to 60 minutes, more preferably 1.5 to 45 minutes, even more preferably 2 to 30 minutes, even more preferably 3 to 20 minutes, and even more preferably 4 to 15 minutes.

[0074] [Example]

[0075] (1) Compound raw materials (1-1) Compound A (cyclic ether compound)

[0076] Compound A-1: ​​Bisphenol A epoxy resin (DIC Corporation)

[0077] Compound A-2: 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexanecarboxylate (manufactured by Daicel Corporation)

[0078] (1-2) Compound B1 (thermal cationic polymerization initiator)

[0079] Compound B1-1: benzylmethyl p-hydroxyphenylsulfonium hexafluoroantimonate (γ-butyrolactone solution) (SI-100L, manufactured by Sanshin Chemical Industry Co., Ltd.)

[0080] Compound B1-2: 4-hydroxyphenyl-methyl-benzylsulfonium tris(pentafluoroethyl)trifluorophosphate (TA-100, manufactured by San-Apro Co., Ltd.)

[0081] Compound B1-3: Quaternary ammonium salt of hexafluoroantimonic acid (CXC-1612, manufactured by KING)

[0082] (1-3) Compound B2 (Iodonium-based cationic photopolymerization initiator)

[0083] Compound B2-1: 4-methylphenyl[4-(1-methylethyl)phenyl]iodonium tetrakis(pentafluorophenyl)borate (PI2074, manufactured by Solvay (Rhodia))

[0084] Compound B2-2: 4-(1-methylethyl)phenyl](4-methylphenyl)iodonium trifluorotris(1,1,2,2,2-pentafluoroethyl)phosphate(1-)(1:1) (IK-1, manufactured by San-Apro Co., Ltd.)

[0085] (1-3) Compound C (radical polymerization initiator) Compound C-1: 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate (Perocta O, manufactured by NOF Corporation)

[0086] (1-4) Compound D (thermal polymerization initiator) Compound D-1: Modified aliphatic polyamine (EH5030S, manufactured by ADEKA Corporation)

[0087] (1-5) Compound E: (cationic photopolymerization initiator) Compound E-1: 4-methylphenyl[4-(1-methylethyl)phenyl]iodonium tetrakis(pentafluorophenyl)borate (PI2074, manufactured by Solvay (Rhodia))

[0088] (1-4) Compound F (solvent): γ-butyrolactone (Tokyo Chemical Industry Co., Ltd.)

[0089] (2) Production of thermosetting resin compositions This will be explained with reference to Table 1.

[0090] Compound A1 and compound A2 were weighed out in the amounts shown in Table 1, charged into a beaker (500 ml), and stirred at 200 rpm for 30 minutes using a Three-One Motor Stirrer BlH300 (manufactured by AS ONE Corporation) to obtain a compound A mixed composition containing both compound A1 and compound A2. The compound A mixed composition contains the compound A1 and the compound A2, with the total amount of the compound A1 and the compound A2 being 100 parts by mass. Compound B, compound C, compound D, compound E and / or compound F, The parts by mass shown in Table 1 were weighed out and mixed with the compound A mixed composition, and the resulting mixture was The mixture was further stirred for 10 minutes under the same stirring conditions to obtain liquid thermosetting resin compositions of Examples and Comparative Examples.

[0091] (3) Physical properties of thermosetting resin composition The physical properties of the liquid thermosetting resin compositions of the comparative examples and examples were measured in the following room temperature environment (25°C, humidity 50%).

[0092] (3-1) Microwave curing 0.15 g of the liquid thermosetting composition was potted onto a 50 × 50 mm PET film (Lumirror 100T60 (Panac Corporation), 100 μm thick) using a microspatula (product number 180 flat stainless steel, AS ONE Corporation). Within 120 seconds, the film was irradiated with microwaves having a wavelength of 2450 MHz at 700 W in a microwave oven (ERD-20(5) manufactured by Yoshii Electric Co., Ltd.) for 2 minutes 30 seconds and for 5 minutes. The following evaluations were carried out.

[0093] After microwave irradiation for a predetermined time, when the thermosetting resin composition on the PET film was pressed with a fingertip, If the inside of the thermosetting resin composition is cured, the fingertip cannot reach the surface of the PET film, and no liquid adheres to the fingertip, the thermosetting resin composition is evaluated as cured ("hard" in Table 1). If the inside of the thermosetting resin composition is cured and the fingertip cannot reach the surface of the PET film, but the liquid adheres to the fingertip, the thermosetting resin composition is evaluated as semi-cured ("semi-cured" in Table 1). If the thermosetting resin composition remained liquid all the way to the inside and the fingertip reached the surface of the PET film, the thermosetting resin composition was evaluated as uncured ("uncured" in Table 1).

[0094] (3-3) Heat curability 0.15 g of the liquid thermosetting composition was potted onto a 50 × 50 mm PET film (Lumirror 100T60 (Panac Corporation), 100 μm thick) using a microspatula (product number 180 flat stainless steel, AS ONE Corporation). Within 120 seconds, the PET film with the thermosetting composition attached was placed in an oven LC-113 (ESPEC Corporation) heated to 100°C, and the following evaluations were performed for heating for 10, 20, and 30 minutes.

[0095] After microwave irradiation for a predetermined time, when the thermosetting resin composition on the PET film was pressed with a fingertip, If the inside of the thermosetting resin composition is cured, the fingertip cannot reach the surface of the PET film, and no liquid adheres to the fingertip, the thermosetting resin composition is evaluated as cured ("hard" in Table 1). If the inside of the thermosetting resin composition is cured and the fingertip cannot reach the surface of the PET film, but the liquid adheres to the fingertip, the thermosetting resin composition is evaluated as semi-cured ("semi-cured" in Table 1). If the thermosetting resin composition remained liquid all the way to the inside and the fingertip reached the surface of the PET film, the thermosetting resin composition was evaluated as uncured ("uncured" in Table 1).

[0096] The compositions and physical properties of the above examples and comparative examples are summarized in Table 1.

[0097] [Table 1]

[0098] From Table 1, when a mixture of a cyclic ether compound and a polymerization initiator is cured by microwave irradiation, the polymerization initiator (a) In the case of a thermal cationic polymerization initiator, it will be thermally cured with low heat generation after 5 minutes of microwave irradiation. (b) In the case of an iodonium-based cationic photopolymerization initiator, it was shown that microwave irradiation for 2 minutes and 30 seconds was sufficient to achieve thermal curing with little heat generation.

Claims

1. A method for manufacturing a composite structure including a member 1 and a member 2, A step A of bonding the member 1 and the member 2 together via a thermosetting resin composition; and step B of irradiating the thermosetting resin composition with microwaves to thermally cure it, A method for producing a composite structure, wherein the thermosetting resin composition contains a cyclic ether compound (compound A) and a polymerization initiator consisting of an iodonium-based cationic photopolymerization initiator (compound B2) and a radical polymerization initiator (compound C).

2. The thermosetting resin composition according to claim 1, which is used in the method for producing the composite structure according to claim 1.

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