Thermal latent polymerization initiator, resin composition containing same, adhesive, sealing material, film, cured product of same, method for producing cured product, and semiconductor device or electronic component

Abstract

The present invention addresses the problem of providing a novel latent polymerization initiator which is excellent in terms of storage stability and enables thermal curing of a resin composition at a low temperature. The present invention also addresses the problem of providing a resin composition and an adhesive or a sealing material, which are excellent in terms of storage stability and can be thermally cured at a low temperature.　The present invention provides: a thermal latent polymerization initiator in which a thermal radical initiator is supported by inorganic ion exchanger particles; a resin composition which contains (A) a radically polymerizable compound and (B) the thermal latent polymerization initiator; and an adhesive or a sealing material which contains the resin composition.

Description

Thermal latent polymerization initiator, resin composition containing the same, adhesive, sealing material, film, cured product thereof, method for producing the cured product, and semiconductor device or electronic component

[0001] The present invention relates to a thermal latent polymerization initiator and a method for producing the same, a resin composition containing the thermal latent polymerization initiator, an adhesive or sealing material containing the same, a film, a cured product thereof, a method for producing the cured product, and a semiconductor device or electronic component containing the cured product.

[0002] Radical polymerization is the most common polymerization method that uses highly active neutral radical species as propagating species to polymerize a variety of vinyl compounds, and is widely used industrially. For example, resin compositions containing radically polymerizable resins such as acrylates and radical polymerization initiators have been developed and are widely used as adhesives, sealants, coating agents, paints, molding materials, etc.

[0003] Thermal radical polymerization is usually initiated using a radical generator such as an azo compound or organic peroxide as a polymerization initiator. Azo compounds have an azo group (-N=N-) that is decomposed by heat or light into two carbon radicals and a nitrogen molecule. Organic peroxides have an -O-O- bond that is decomposed by heat into oxygen radicals. Such radical generators are highly reactive to light and / or heat and may pose an explosion risk if handled improperly, so they must be stored in a cool, dark place.

[0004] Furthermore, when a radical generator is contained in a resin composition as a polymerization initiator, the radical generator is gradually deactivated during storage of the resin composition due to its high reactivity, resulting in problems such as the polymerization reaction not proceeding when used, or an unintended polymerization reaction proceeding during storage, resulting in an increase in viscosity of the resin composition. In order to improve the storage stability of organic peroxides in resin compositions, it is known to use microencapsulated organic peroxides as latent catalysts (see, for example, Patent Documents 1 and 2).

[0005] JP-A No. 57-12039 JP-A No. 07-118610

[0006] On the other hand, resin compositions containing radical initiators with high storage stability sometimes require a curing reaction at high temperatures.

[0007] An object of the present invention is to provide a novel latent polymerization initiator that has excellent storage stability and enables a resin composition to be thermally cured at low temperatures, and to provide a resin composition, adhesive, or sealant that has excellent storage stability and enables thermal curing at low temperatures.

[0008] Specific means for solving the above problems are as follows. Aspects of the present invention include the following thermal latent polymerization initiator and a method for producing the same, a resin composition containing the thermal latent polymerization initiator, an adhesive or sealant containing the same, a film, a cured product thereof, a method for producing the cured product, and a semiconductor device or electronic component containing the cured product. (1) A thermal latent polymerization initiator in which a thermal radical initiator is supported on inorganic ion exchanger particles. (2) The thermal latent polymerization initiator according to (1) above, in which the thermal radical initiator is an azo-based radical initiator. (3) The thermal latent polymerization initiator according to (1) or (2) above, in which the inorganic ion exchanger is an inorganic cation exchanger. (4) The thermal latent polymerization initiator according to (3) above, in which the inorganic cation exchanger is a phosphate-based inorganic cation exchanger. (5) The thermal latent polymerization initiator according to (4) above, in which the phosphate-based inorganic cation exchanger is zirconium phosphate. (6) A resin composition comprising (A) a radical polymerizable compound and (B) the thermal latent polymerization initiator described in any one of (1) to (5) above. (7) The resin composition described in (6) above, further comprising (C) a thermal radical initiator elimination accelerator. (8) The resin composition described in (7) above, wherein the (C) thermal radical initiator elimination accelerator is a Lewis basic substance. (9) An adhesive or sealant comprising the resin composition described in any one of (6) to (8) above. (10) A film comprising the resin composition described in any one of (6) to (8) above. (11) A cured product obtained by curing the resin composition described in any one of (6) to (8) above. (12) A method for producing a cured product, comprising heating the resin composition described in any one of (6) to (8) above. (13) A semiconductor device or electronic component comprising the cured product described in (11) above. (14) A method for producing a thermal latent polymerization initiator, comprising mixing a thermal radical initiator and an inorganic ion exchanger in the presence of a medium at a temperature lower than the 10-hour half-life temperature of the thermal radical initiator. (15) The method for producing a thermal latent polymerization initiator according to (14), wherein the thermal radical initiator is an azo-based radical initiator.

[0009] According to one aspect of the present invention, there are provided a novel thermal latent polymerization initiator that has excellent storage stability and enables thermal curing of a resin composition at low temperatures, and a method for producing the same. Also, according to another aspect of the present invention, there are provided a resin composition that has excellent storage stability and enables thermal curing at low temperatures, an adhesive or encapsulant containing the same, a film, a cured product thereof, a method for producing the cured product, and a semiconductor device or electronic component containing the cured product.

[0010] In this specification, following the convention in the field of synthetic resins, a name including the term "resin," which normally refers to a polymer (particularly a synthetic polymer), may be used for a component constituting a resin composition before curing, even if the component is not a polymer, for example, a prepolymer compound before curing.

[0011] [Thermal Latent Polymerization Initiator] The thermal latent polymerization initiator according to one embodiment of the present invention is a thermal latent polymerization initiator in which a thermal radical initiator is supported on inorganic ion exchanger particles. According to this embodiment, a novel thermal latent polymerization initiator that has excellent storage stability and enables thermal curing of a resin composition at low temperatures can be provided.

[0012] To stabilize thermal radical initiators, the present inventors focused on inorganic ion exchangers. An inorganic ion exchanger is a substance whose skeleton is composed of inorganic atoms other than carbon atoms (e.g., zirconium, antimony, bismuth, magnesium, titanium, hafnium, germanium, tin, lead, aluminum, etc.) and has ion exchange capacity. Inorganic ion exchangers have negatively or positively charged ion exchange sites, allowing them to exchange captured ions for other ions. The present inventors discovered that (1) a thermal radical initiator can be supported on this inorganic ion exchanger, and (2) a substance in which a thermal radical initiator is supported on an inorganic ion exchanger has improved storage stability and enables low-temperature thermal curing of a resin composition without reducing the activity of the thermal radical initiator itself. The mechanism behind this is thought to be, but is not limited to, that the ionized thermal radical initiator is supported and stabilized on the ion exchange sites of the inorganic ion exchanger, thereby imparting latency, and that the thermal radical initiator is desorbed from the inorganic ion exchanger and activated under the thermal curing conditions of the resin composition.

[0013] Thermal Radical Initiator The thermal latent polymerization initiator of this embodiment is a substance in which a thermal radical initiator is supported on inorganic ion exchanger particles. The thermal radical initiator is a substance that generates radicals as active species by heat and promotes polymerization of a radically polymerizable compound. Examples of the thermal radical initiator include, but are not limited to, azo radical initiators having an azo group (-N=N-) that generates carbon radicals, and organic peroxide initiators having an -O-O- bond that generates oxygen radicals. In this embodiment, from the viewpoints of ease of support on an inorganic ion exchanger and stability, the thermal radical initiator is preferably an azo radical initiator.

[0014] In this embodiment, the azo radical initiator is preferably an azo compound having a basic group or an azo compound having an acidic group. The type of inorganic ion exchanger to serve as the host is selected depending on whether the azo compound has a basic group or an acidic group.

[0015] In this specification, an azo compound having a basic group is an azo compound having an azo group in its molecular structure and a proton (H ＋ Azo compounds having a basic group are compounds that can accept a proton (H ＋) and is supported at its ion exchange site on the inorganic cation exchanger described below. Examples of azo compounds having a basic group include compounds having heteroatoms other than azo groups in their molecular structure. The heteroatoms other than azo groups can be contained in the compound in the form of functional groups containing heteroatoms. Examples of such functional groups containing heteroatoms include, but are not limited to, hydroxyl groups, carboxyl groups, ether groups, ester groups, phosphate ester groups, amino groups, imino groups, nitrile groups, thiol groups, sulfide groups, sulfoxide groups, disulfide groups, thioester groups, and amide groups.Specific examples of azo compounds having a basic group include 2,2'-azobis(N-cyclohexyl-2-methylpropionamide), 2,2'-azobis[N-(2-methylpropyl)-2-methylpropionamide], 2,2'-azobis(N-butyl-2-methylpropionamide) (for example, product name: VAm-110, Fujifilm Wako Pure Chemical Industries, Ltd.), 2,2'-azobis[N-(2-methylethyl)-2-methylpropionamide], and 2,2'-azobis(N-hexyl-2-methylpropionamide). ), 2,2'-azobis(N-propyl-2-methylpropionamide), 2,2'-azobis(N-ethyl-2-methylpropionamide), 2,2'-azobis{2-methyl-N-[1,1-bis(hydroxymethyl)-2-hydroxyethyl]propionamide}, 2,2'-azobis{2-methyl-N-[2-(1-hydroxybutyl)]propionamide}, 2,2'-azobis[2-methyl-N-(2-hydroxyethyl)propionamide] (for example, product name: VA-086, Fujifilm Chemical Industry Co., Ltd. Wako Pure Chemical Industries, Ltd.), 2,2'-azobis[N-(2-propenyl)-2-methylpropionamide], 2,2'-azobis[2-(2-imidazolin-2-yl)propane]disulfate dihydrate, 2,2'-azobis[2-(2-imidazolin-2-yl)propane] (for example, product name: VA-061, Fujifilm Wako Pure Chemical Industries, Ltd.), 2,2'-azobis[N-(2-carboxyacyl)-2-methyl-propionamidine], 2,2'-azobis{2-[N-(2-carboxyethyl)amine] diimide]propane}, azodicarbonamide, azodicarbon-(N-methyl)amide, 1,1'-azobis(cyclohexane-1-carbonitrile) (e.g., product name: V-40, Fujifilm Wako Pure Chemical Industries, Ltd.), 2,2'-azobis[2-(2-imidazolin-2-yl)propane]dihydrochloride (e.g., product name: VA-044, Fujifilm Wako Pure Chemical Industries, Ltd.), 2,2'-azobis(2-methylpropionamidine)dihydrochloride (e.g., product name: V-50, Fujifilm Wako Pure Chemical Industries, Ltd.), dimethyl 2,2'-azobis(2-methylpropionate) (e.g., product name: V-601, Fujifilm Wako Pure Chemical Industries, Ltd.), and the like.These azo compounds having a basic group may be used alone or in combination of two or more kinds.

[0016] In this specification, an azo compound having an acidic group is an azo compound having an azo group in its molecular structure and a proton (H ＋ Azo compounds having a group capable of donating a proton (H ＋ ) and is supported at its ion exchange site on the inorganic anion exchanger described below. Examples of azo compounds having an acidic group include compounds having a heteroatom other than the azo group in their molecular structure. The heteroatom other than the azo group can be contained in the compound in the form of a functional group containing the heteroatom. Examples of such heteroatom-containing functional groups include, but are not limited to, a hydroxyl group, a carboxyl group, a thiol group, a sulfo group, and a phosphate group. Specific examples of azo compounds having an acidic group include, but are not limited to, 4,4'-azobis(4-cyanovaleric acid) (e.g., product name: V-501, Fujifilm Wako Pure Chemical Industries, Ltd.) and 2,2'-azobis[N-(2-carboxyethyl)-2-methylpropionamidine] tetrahydrate (e.g., product name: VA-057, Fujifilm Wako Pure Chemical Industries, Ltd.). These azo compounds having an acidic group may be used alone or in combination of two or more.

[0017] The 10-hour half-life temperature (T10) of the thermal radical initiator is preferably 35 to 120°C, more preferably 40 to 115°C, and even more preferably 45 to 110°C.

[0018] Inorganic ion exchanger particles The thermal latent polymerization initiator of this embodiment is a substance in which a thermal radical initiator is supported on inorganic ion exchanger particles. The inorganic ion exchanger particles refer to particulate inorganic ion exchangers. The inorganic ion exchanger refers to a substance whose skeleton is composed of inorganic atoms other than carbon atoms (e.g., zirconium, antimony, bismuth, magnesium, titanium, hafnium, germanium, tin, lead, aluminum, etc.) and has ion exchange capacity. The inorganic ion exchanger has negatively or positively charged ion exchange sites and can exchange captured ions for other ions. Examples of inorganic ion exchangers include clay minerals such as silicates, such as montmorillonite, vermiculite, beidellite, kaolinite, dickite, nacrite, halloysite, smectite, allophane, heractite, sepiolite, bentonite, pyrophyllite, muscovite, margarite, antigorite, chrysotile, talc, phlogopite, and xanthophyllite; hydrous sodium silicates such as kanemite, makatite, ailerite, magadiite, and Kenyaite; calcium silicates such as tobermorite; Examples of inorganic ion exchanger particles include, but are not limited to, tetravalent metal phosphates such as zirconium phosphate and titanium phosphate; titanates such as potassium titanate, barium titanate, strontium titanate, calcium titanate, magnesium titanate, cobalt titanate, nickel titanate, lead titanate, and zinc titanate; and uranates, vanadates, niobates, tungstates, molybdates, aluminates, basic copper acetate, hydrotalcite, hydrous bismuth oxide, hydrous magnesium oxide, and hydrous aluminum oxide. These inorganic ion exchanger particles may be used alone or in combination of two or more.

[0019] In this specification, an inorganic ion exchanger having negatively charged ion exchange sites and cation exchange capacity is referred to as an inorganic cation exchanger. In this specification, an inorganic ion exchanger having positively charged ion exchange sites and anion exchange capacity is referred to as an inorganic anion exchanger. In this embodiment, the inorganic cation exchanger can support an azo compound having a basic group as a thermal radical initiator at its ion exchange sites. In this embodiment, the inorganic anion exchanger can support an azo compound having an acidic group as a thermal radical initiator at its ion exchange sites. In one embodiment of this embodiment, the inorganic ion exchanger is an inorganic cation exchanger. In one embodiment, the inorganic cation exchanger is preferably a phosphate-based inorganic cation such as a phosphate salt of a tetravalent metal, such as zirconium phosphate or titanium phosphate, a clay mineral such as smectite, a hydrous sodium silicate such as kanemite or magadiite, a niobate, or a titanate, and more preferably a phosphate-based inorganic cation such as zirconium phosphate or titanium phosphate. In one embodiment, the phosphate-based inorganic cation is zirconium phosphate. In one embodiment of this aspect, the inorganic ion exchanger is an inorganic anion exchanger. In one embodiment, the inorganic anion exchanger is preferably hydrotalcite.

[0020] Zirconium phosphates have various compositions (e.g., P / Zr molar ratios of 2.0 or more, 2.0, 1.5, 1.0, or 1.0 or less) and structures (e.g., amorphous, two-dimensional layered structure, and three-dimensional network structure) depending on the production method (Katsuhiko, ITOHO, Yashushi NAKAJIMA, Journal of Ion Exchange, Vol. 4, No. 3 (1994)). In the present embodiment, zirconium phosphates having an amorphous or two-dimensional layered structure can be used.

[0021] In this embodiment, the inorganic ion exchanger particles may have an average particle size of 1 nm to 100 μm. In one embodiment, the inorganic ion exchanger particles have an average particle size of, for example, 0.1 to 100 μm, such as 0.5 to 50 μm, or 1 to 10 μm. In one embodiment, the inorganic ion exchanger particles have an average primary particle size of, for example, 1 nm to 500 nm, such as 5 nm to 450 nm, or 10 nm to 400 nm. A resin composition containing a thermal latent polymerization initiator obtained using inorganic ion exchanger particles with such a very small average particle size can penetrate narrow gaps and can be used for bonding or sealing narrow gaps. In this embodiment, inorganic ion exchanger particles with different average particle sizes may be used in combination. In this specification, the average particle size refers to the particle size at 50% of the cumulative value in the particle size distribution on a volume basis, as measured by a laser diffraction / scattering method. Alternatively, the average particle size can be determined as the average value when the particle diameters (long axis length of the plate surface) of 20 random particles are measured using a transmission electron microscope (TEM), or the average value when the particle diameters (long axis length of the plate surface) of 20 random particles are measured using a scanning electron microscope (SEM) (magnification 5000x). In this specification, the method for measuring the average particle size is prioritized over transmission electron microscope (TEM), and when the majority of particles are clearly 0.10 μm or less and the average particle size cannot be measured using a scanning electron microscope (SEM) (magnification 5000x), the value measured using a transmission electron microscope (TEM) is used as the average particle size.

[0022] The shape of the inorganic ion exchanger particles is not particularly limited, and may be any of spherical, flaky, needle-like, irregular, etc.

[0023] The method for producing the thermal latent polymerization initiator of this embodiment is not particularly limited, and may be, for example, a method comprising mixing a thermal radical initiator and an inorganic ion exchanger in the presence of a medium at a temperature lower than the 10-hour half-life temperature of the thermal radical initiator. By mixing at a temperature lower than the 10-hour half-life temperature of the thermal radical initiator, unintended decomposition of the thermal radical initiator can be suppressed. The method for producing a thermal latent polymerization initiator is one embodiment of the present invention. The medium may be any liquid medium that can dissolve and / or be miscible with the thermal radical initiator, such as water; alcohols such as methanol, ethanol, propanol, and butanol; esters such as ethyl acetate and methyl acetate; ketones such as acetone and 2-butanone; ethers such as diethyl ether, dimethyl ether, diisopropyl ether, and tetrahydrofuran; amides such as dimethylformamide and dimethylacetamide; alkanes such as hexane and heptane; aromatic hydrocarbons such as benzene and toluene; dimethyl sulfoxide, N-methylpyrrolidone, acetonitrile, chloroform, and dichloromethane; and mixtures of these liquid media. Among these, water, alcohol, or ester is preferred. The mixing temperature is lower than the 10-hour half-life temperature of the thermal radical initiator, preferably at least 10°C lower than the 10-hour half-life temperature of the thermal radical initiator, and more preferably at least 20°C lower than the 10-hour half-life temperature of the thermal radical initiator. Mixing can be performed, for example, by stirring for 30 minutes to 48 hours. After completion of the reaction, the mixture is separated from the liquid medium and washed with an appropriate washing medium to obtain a thermal latent polymerization initiator in which the thermal radical initiator is supported on inorganic ion exchanger particles. The washing medium may be the same as the liquid medium used during the mixing, or a different liquid medium may be used. After washing, the thermal latent polymerization initiator is a gel-like substance containing the liquid medium. Therefore, the liquid medium in the thermal latent polymerization initiator can be removed by drying as necessary. The thermal latent polymerization initiator can be used either in a state containing the liquid medium or in a state from which the liquid medium has been removed.

[0024] The thermal latent polymerization initiator of this embodiment is believed to be able to support a thermal radical initiator depending on the space volume or surface area of ​​the ion exchange sites of the inorganic ion exchanger. For example, the thermal radical initiator can be supported in an amount of 1 to 50 mass%, preferably 10 to 50 mass%, based on the total mass of the thermal latent polymerization initiator. When the thermal radical initiator is an azo-based radical initiator, the amount of the thermal radical initiator (mass%) in the thermal latent polymerization initiator can be calculated by determining the mass of nitrogen atoms contained in the thermal latent polymerization initiator using an elemental analyzer. Specifically, the content (mass%) of the thermal radical initiator in the thermal latent polymerization initiator can be estimated by the formula: (mass fraction (mass%) of nitrogen atoms obtained by elemental analysis) / (atomic weight of nitrogen [g / mol] × number of nitrogen atoms [units] per molecule of thermal radical initiator)) × molecular weight of the thermal radical initiator [g / mol].

[0025] [Resin Composition] The resin composition according to one embodiment of the present invention includes (A) a radical polymerizable compound and (B) the thermal latent polymerization initiator of the above embodiment. According to this embodiment, it is possible to provide a resin composition that has excellent storage stability and can be thermally cured at low temperatures.

[0026] (A) Radically Polymerizable Compound The resin composition of this embodiment contains (A) a radically polymerizable compound (hereinafter also referred to as "component (A)"). Examples of the radically polymerizable compound include, but are not limited to, compounds having an unsaturated double bond such as (meth)acrylate compounds, cyanoacrylate compounds, maleimide compounds, and methylene malonates (2-methylene-1,3-dicarbonyl compounds and derivatives thereof), and mixtures of compounds having an unsaturated double bond and thiol compounds (mixtures capable of undergoing an ene-thiol reaction).

[0027] In this specification, a (meth)acrylate compound is a compound having at least one (meth)acryloyl group in the molecule, and examples thereof include a monofunctional (meth)acrylate compound having one (meth)acryloyl group and a polyfunctional (meth)acrylate compound having two or more (meth)acryloyl groups. In this specification, the term "(meth)acryloyl group" includes both a methacryloyl group and an acryloyl group. Furthermore, the term "(meth)acrylate compound" includes both an acrylate compound and a methacrylate compound. Examples of monofunctional (meth)acrylate compounds include: -ethyl (meth)acrylate, trifluoroethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, glycidyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, isoamyl (meth)acrylate, cyclohexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isodecyl (meth)acrylate, isobornyl (meth)acrylate, stearyl (meth)acrylate, lauryl (meth)acrylate, phenoxyethyl (meth)acrylate, benzyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate esters of monohydric alcohols and (meth)acrylic acid such as ethylene glycol acrylate, ethoxydiethylene glycol (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, phenoxypolyethylene glycol (meth)acrylate, butoxydiethylene glycol (meth)acrylate, methoxydipropylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, 2-ethylhexyldiethylene glycol (meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, and 3-phenoxybenzyl (meth)acrylate; 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, and octyl acrylate;Nonyl acrylate, isononyl acrylate, 3,3,5-trimethylcyclohexyl acrylate, cyclic trimethylolpropane formal acrylate, 1-naphthalenemethyl (meth)acrylate, 1-ethylcyclohexyl (meth)acrylate, 1-methylcyclohexyl (meth)acrylate, 1-ethylcyclopentyl (meth)acrylate, 1-methylcyclopentyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, dicyclopentanyl (meth)acrylate acrylate, nonylphenoxy polyethylene glycol (meth)acrylate, tetrahydrodicyclopentadienyl (meth)acrylate, 2-(o-phenylphenoxy)ethyl (meth)acrylate, isobornylcyclohexyl (meth)acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl (meth)acrylate, 1-adamantyl (meth)acrylate, 3-hydroxy-1-adamantyl (meth)acrylate, 2-methyl-2-adamantanyl (meth)acrylate, 2-ethyl-2-adamantanyl (meth)acrylate meth)acrylate, 2-isopropyladamantan-2-yl (meth)acrylate, 3-hydroxy-1-adamantyl (meth)acrylate, (adamantan-1-yloxy)methyl (meth)acrylate, 2-isopropyl-2-adamantyl (meth)acrylate, 1-methyl-1-ethyl-1-adamantylmethanol (meth)acrylate, 1,1-diethyl-1-adamantylmethanol (meth)acrylate, 2-cyclohexylpropan-2-yl (meth)acrylate, 1-isopropylcyclohexyl (meth)acrylate acrylate, 1-methylcyclohexyl (meth)acrylate, 1-ethylcyclopentyl (meth)acrylate, 1-methylcyclohexyl (meth)acrylate, tetrahydropyranyl (meth)acrylate, tetrahydro-2-furanyl (meth)acrylate, 2-oxotetrahydrofuran-3-yl (meth)acrylate, (5-oxotetrahydrofuran-2-yl)methyl (meth)acrylate, (2-oxo-1,3-dioxolan-4-yl)methyl (meth)acrylate, N-acryloyloxyethyl hexahydrophthalimide,Examples of the acrylate include, but are not limited to, mono(meth)acrylates of polyhydric alcohols such as α-acryloyl-ω-methoxypoly(oxyethylene) and 1-ethoxyethyl(meth)acrylate, or esters of monohydric alcohols and (meth)acrylic acid. These may be used alone or in combination of two or more. Examples of polyfunctional (meth)acrylate compounds include diacrylate and / or dimethacrylate of tris(2-hydroxyethyl)isocyanurate; tris(2-hydroxyethyl)isocyanurate triacrylate and / or trimethacrylate; trimethylolpropane triacrylate and / or trimethacrylate, or oligomers thereof; pentaerythritol triacrylate and / or trimethacrylate, or oligomers thereof; polyacrylate and / or polymethacrylate of dipentaerythritol; tris(acryloxyethyl)isocyanurate; caprolactone-modified tris(acryloxyethyl)isocyanurate; caprolactone-modified tris(methacryloxyethyl)isocyanurate; polyacrylate and / or polymethacrylate of alkyl-modified dipentaerythritol; caprolactone-modified dipentaerythritol Examples of the (meth)acrylate compound include, but are not limited to, polyacrylates and / or polymethacrylates of teflon, ethoxylated bisphenol A diacrylate and / or ethoxylated bisphenol A dimethacrylate, dihydrocyclopentadiethyl acrylate and / or dihydrocyclopentadiethyl methacrylate, polyester acrylate and / or polyester methacrylate, dimethylol-tricyclodecane diacrylate, poly(meth)acrylate of ditrimethylolpropane, polyurethanes having two or more (meth)acryloyl groups per molecule, polyesters having two or more (meth)acryloyl groups per molecule, phenoxyethyl acrylate, isobornyl acrylate, phenoxydiethylene glycol (meth)acrylate, 4-tert-butylcyclohexyl acrylate, and epoxy resin half acrylate. The (meth)acrylate compound may be any one of the above-mentioned (meth)acrylate compounds,Commercially available (meth)acrylate compounds include, but are not limited to, polyester acrylate (product name: EBECRYL 810) manufactured by Daicel-Allnex Corporation, ditrimethylolpropane tetraacrylate (product name: EBECRYL 140) manufactured by Daicel-Allnex Corporation, polyester acrylate (product name: M7100) manufactured by Toagosei Co., Ltd., dimethylol-tricyclodecane diacrylate (product name: Light Acrylate DCP-A) manufactured by Kyoeisha Chemical Co., Ltd., and neopentyl glycol-modified trimethylolpropane diacrylate (product name: Kayarad R-604) manufactured by Nippon Kayaku Co., Ltd.

[0028] The cyanoacrylate compound is H ２Known groups represented by the formula C═C(CN)—COOR can be used. In this formula, R is an ester residue such as an alkyl group, cycloalkyl group, alkenyl group, cycloalkenyl group, alkynyl group, or aryl group. The number of carbon atoms in the ester residue is not particularly limited, but typically, those having 1 to 8 carbon atoms can be used. Ester residues consisting of substituted hydrocarbon groups such as alkoxyalkyl groups and trialkylsilylalkyl groups can also be used. Examples of cyanoacrylate compounds include alkyl and cycloalkyl cyanoacrylates such as methyl cyanoacrylate, ethyl cyanoacrylate, propyl cyanoacrylate, butyl cyanoacrylate, and cyclohexyl cyanoacrylate; alkenyl and cycloalkenyl cyanoacrylates such as allyl cyanoacrylate, methallyl cyanoacrylate, and cyclohexenyl cyanoacrylate; alkynyl cyanoacrylates such as propanegyl cyanoacrylate; aryl cyanoacrylates such as phenyl cyanoacrylate and toluyl cyanoacrylate; methoxyethyl cyanoacrylate, ethoxyethyl cyanoacrylate, and furfuryl cyanoacrylate containing heteroatoms; trimethylsilylmethyl cyanoacrylate, trimethylsilylethyl cyanoacrylate, trimethylsilylpropyl cyanoacrylate, and dimethylvinylsilylmethyl cyanoacrylate containing silicon; but are not limited thereto.These compounds may be used alone or in combination of two or more.

[0029] Examples of maleimide compounds include N,N'-(4,4'-diphenylmethane)bismaleimide and bisphenol A. Examples of suitable bismaleimides include, but are not limited to, diphenyl ether bismaleimide, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6'-bismaleimide-(2,2,4-trimethyl)hexane, bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane, m-phenylene bismaleimide (N,N'-1,3-phenylene bismaleimide), 1,6-bismaleimidehexane, 1,2-bismaleimideethane (N,N'-ethylene dimaleimide), N,N'-(1,2-phenylene)bismaleimide, N,N'-1,4-phenylene dimaleimide, N,N'-(sulfonyldi-p-phenylene)dimaleimide, and N,N'-[3,3'-(1,3-phenylenedioxy)diphenyl]bismaleimide. These may be used alone or in combination of two or more.

[0030] When a low room temperature modulus is required for the cured resin composition, the maleimide compound is preferably a maleimide compound having a hydrocarbon group derived from a dimer acid. Such maleimide compounds are described, for example, in JP 2015-193725 A. Commercially available maleimide compounds having a hydrocarbon group derived from a dimer acid include, but are not limited to, products under the trade names "BMI-689," "BMI-1500," and "BMI-1700," which are liquid at 25°C, and "BMI-3000," which is solid at 25°C (all manufactured by Designer Molecules Inc.). These compounds may be used alone or in combination of two or more.

[0031] Methylene malonates are malonates having at least one methylene group in the molecule, including monofunctional methylene malonates having one methylene group and polyfunctional methylene malonates having two or more methylene groups. The methylene malonates preferably have a molecular weight of 220 or more. There are no particular limitations on the type of methylene malonate that can be used, and various disclosed methylene malonates can be used, including compounds described in WO 2018 / 212330 A1 and the like. Methylene malonates may be used alone or in combination of two or more.

[0032] The thiol compound in the mixture of the compound having an unsaturated double bond and the thiol compound is a compound containing at least one thiol group, and the thiol group can undergo a radical addition reaction (ene-thiol reaction) with the unsaturated double bond of the compound having an unsaturated double bond. Thiol compounds are broadly classified into thiol compounds having a hydrolyzable partial structure such as an ester bond in the molecule (i.e., hydrolyzable) and thiol compounds not having such a partial structure (i.e., non-hydrolyzable). Examples of hydrolyzable thiol compounds include trimethylolpropane tris(3-mercaptopropionate) (e.g., TMMP manufactured by SC Organic Chemical Co., Ltd.), tris-[(3-mercaptopropionyloxy)-ethyl]-isocyanurate (e.g., TEMPIC manufactured by SC Organic Chemical Co., Ltd.), pentaerythritol tetrakis(3-mercaptopropionate) (e.g., PEMP manufactured by SC Organic Chemical Co., Ltd.), tetraethylene glycol bis(3-mercaptopropionate) (e.g., EG manufactured by SC Organic Chemical Co., Ltd.), and the like. Examples of the dimer include, but are not limited to, dipentaerythritol hexakis(3-mercaptopropionate) (for example, DPMP manufactured by SC Organic Chemical Co., Ltd.), pentaerythritol tetrakis(3-mercaptobutyrate) (for example, Karenz MT (registered trademark) PE1 manufactured by Showa Denko K.K.), and 1,3,5-tris(3-mercaptobutyryloxyethyl)-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (for example, Karenz MT (registered trademark) NR1 manufactured by Showa Denko K.K.). These may be used alone or in combination of two or more. Examples of the non-hydrolyzable polyfunctional thiol compound include 1,3,4,6-tetrakis(2-mercaptoethyl)glycoluril (e.g., Shikoku Chemical Industry Co., Ltd.: TS-G), 1,3,4,6-tetrakis(3-mercaptopropyl)glycoluril (e.g., Shikoku Chemical Industry Co., Ltd.: C3 TS-G), 1,3,4,6-tetrakis(mercaptomethyl)glycoluril, 1,3,4,6-tetrakis(mercaptomethyl)-3a-methylglycoluril, 1,3,4,6-tetrakis(2-mercaptoethyl)-3a-methylglycoluril, 1,3,4,6-tetrakis(3-mercaptopropyl)-3a-methylglycoluril, 1,3,4,6-tetrakis(mercaptomethyl)-3a,6a-dimethylglycoluril, 1,3,4,6-tetrakis(2-mercaptoethyl)-3a,6a-dimethylglycoluril, 1,3,4,6-tetrakis(3-mercaptopropyl)-3a,6a-dimethylglycoluril, 1,3,4,6-tetrakis(mercaptomethyl)-3a,6a-diphenylglycoluril, 1,3,4,6-tetrakis(2-mercaptoethyl)-3a,6a- Diphenyl glycol uril, 1,3,4,6-tetrakis(3-mercaptopropyl)-3a,6a-diphenyl glycol uril, tris(3-mercaptopropyl)isocyanurate, 1,3,5-tris[3-(2-mercaptoethylsulfanyl)propyl]isocyanurate, 1,3,5-tris[2-(3-mercaptopropoxy)ethyl]isocyanurate, pentaerythritol trippropanethiol (e.g., PEPT manufactured by SC Organic Chemical Co., Ltd.), 3-[2,3-bis(3-sulfanylpropoxy)propoxy]propane- 1-Thiol, 3-[2,2-bis[(3-mercaptopropoxy)methyl]butoxy]-1-propanethiol, pentaerythritol tetrapropanethiol, 1,2,3-tris(mercaptomethylthio)propane, 1,2,3-tris(2-mercaptoethylthio)propane, 1,2,3-tris(3-mercaptopropylthio)propane, 4-mercaptomethyl-1,8-dimercapto-3,6-dithiaoctane, 5,7-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, 4,7-dimercaptomethyl- 1,11-dimercapto-3,6,9-trithiaundecane, 4,8-dimercaptomethyl-1,11-dimercapto-3,6,9-trithiaundecane, tetrakis(mercaptomethylthiomethyl)methane, tetrakis(2-mercaptoethylthiomethyl)methane, tetrakis(3-mercaptopropylthiomethyl)methane, 1,1,3,3-tetrakis(mercaptomethylthio)propane, 1,1,2,2-tetrakis(mercaptomethylthio)ethane, 1,1,5,5-tetrakis(mercaptomethylthio)-3-thiapentane, 1,1,6,6-tetrakis(mercaptomethylthio)-3,4-dithiahexane, 2,2-bis(mercaptomethylthio)ethanethiol, 3-mercaptomethylthio-1,7-dimercapto-2,6-dithiaheptane, 3,6-bis(mercaptomethylthio)-1,9-dimercapto-2,5,8-trithianonane, 3-mercaptomethylthio-1,6-dimercapto-2,5-dithiahexane, 1,1,9,9-tetrakis(mercaptomethylthio)-5-(3,3-bis(mercaptomethylthio)-1-thiapropyl)3,7-dithianonane, tris (2,2-bis(mercaptomethylthio)ethyl)methane, tris(4,4-bis(mercaptomethylthio)-2-thiabutyl)methane, tetrakis(2,2-bis(mercaptomethylthio)ethyl)methane, tetrakis(4,4-bis(mercaptomethylthio)-2-thiabutyl)methane, 3,5,9,11-tetrakis(mercaptomethylthio)-1,13-dimercapto-2,6,8,12-tetrathiatridecane, 3,5,9,11,15,17-hexakis(mercaptomethylthio)-1,19-dimercapto-2,6,8,12,1 4,18-Hexathianonadecane, 9-(2,2-bis(mercaptomethylthio)ethyl)-3,5,13,15-tetrakis(mercaptomethylthio)-1,17-dimercapto-2,6,8,10,12,16-hexathiaheptadecane, 3,4,8,9-tetrakis(mercaptomethylthio)-1,11-dimercapto-2,5,7,10-tetrathiaundecane, 3,4,8,9,13,14-hexakis(mercaptomethylthio)-1,16-dimercapto-2,5,7,10,12,15-hexathiahexadecane, 8-[bis(mercaptomethylthio)ethyl]-3,5,13,15-tetrakis(mercaptomethylthio)-1,17-dimercapto-2,6,8,10,12,16-hexathiaheptadecane 4-[3,5-bis(mercaptomethylthio)-7-mercapto-2,6-dithiaheptylthio]-6-mercaptomethylthio-1,3-dithiane, 1,1-bis[4-(6-mercaptomethylthio)-1,3-dithianylthio]-1,3-dithiane, 1,1-bis[4-(6-mercaptomethylthio)-1,3-dithianylthio]-1,3-dithiane,3-bis(mercaptomethylthio)propane, 1-[4-(6-mercaptomethylthio)-1,3-dithianylthio]-3-[2,2-bis(mercaptomethylthio)ethyl]-7,9-bis(mercaptomethylthio)-2,4,6,10-tetrathiaundecane, 3-[2-(1,3-dithietanyl)]methyl-7,9-bis(mercaptomethylthio)-1,11-dimercapto-2,4,6,10-tetrathiaundecane, 9-[2-(1,3-dithietanyl)]methyl-3,5,13,15-tetrakis(mercaptomethylthio)-1,17 -dimercapto-2,6,8,10,12,16-hexathiaheptadecane, 3-[2-(1,3-dithietanyl)]methyl-7,9,13,15-tetrakis(mercaptomethylthio)-1,17-dimercapto-2,4,6,10,12,16-hexathiaheptadecane, 4,6-bis[4-(6-mercaptomethylthio)-1,3-dithianylthio]-6-[4-(6-mercaptomethylthio)-1,3-dithianylthio]-1,3-dithiane, 4-[3,4,8,9-tetrakis(mercaptomethylthio)-11-mercapto-2,5,7, 10-tetrathiaundecyl]-5-mercaptomethylthio-1,3-dithiolane, 4,5-bis[3,4-bis(mercaptomethylthio)-6-mercapto-2,5-dithiahexylthio]-1,3-dithiolane, 4-[3,4-bis(mercaptomethylthio)-6-mercapto-2,5-dithiahexylthio]-5-mercaptomethylthio-1,3-dithiolane, 4-[3-bis(mercaptomethylthio)methyl-5,6-bis(mercaptomethylthio)-8-mercapto-2,4,7-trithiaoctyl]-5-mercaptomethylthio-1, 3-Dithiolane, 2-{bis[3,4-bis(mercaptomethylthio)-6-mercapto-2,5-dithiahexylthio]methyl}-1,3-dithietane, 2-[3,4-bis(mercaptomethylthio)-6-mercapto-2,5-dithiahexylthio]mercaptomethylthiomethyl-1,3-dithietane, 2-[3,4,8,9-tetrakis(mercaptomethylthio)-11-mercapto-2,5,7,10-tetrathiaundecylthio]mercaptomethylthiomethyl-1,3-dithietane, 2-[3-bis(mercaptomethylthio)methyl-5,Examples of suitable mercaptomethylthio compounds include, but are not limited to, 6-bis(mercaptomethylthio)-8-mercapto-2,4,7-trithiaoctyl]mercaptomethylthiomethyl-1,3-dithietane and 4-{1-[2-(1,3-dithietanyl)]-3-mercapto-2-thiapropylthio}-5-[1,2-bis(mercaptomethylthio)-4-mercapto-3-thiabutylthio]-1,3-dithiolane. These compounds may be used alone or in combination of two or more.

[0033] In one embodiment, the content of the radical polymerizable compound (A) in the resin composition is preferably 1 to 99 parts by mass, more preferably 5 to 50 parts by mass, and even more preferably 7 to 30 parts by mass, per 100 parts by mass of the total resin composition. In another embodiment, the content of the radical polymerizable compound (A) in the resin composition is preferably 30 to 99 parts by mass, more preferably 50 to 99 parts by mass, and even more preferably 60 to 99 parts by mass, per 100 parts by mass of the total resin composition. The content of the radical polymerizable compound (A) in the resin composition is preferably 40 to 99 parts by mass, more preferably 45 to 99.5 parts by mass, and even more preferably 50 to 98 parts by mass, per 100 parts by mass of all organic materials (excluding low-stress-imparting materials such as organic fillers and elastomers) contained in the resin composition.

[0034] (B) Thermal Latent Polymerization Initiator The resin composition of this aspect contains (B) the thermal latent polymerization initiator of the above embodiment (hereinafter also referred to as "component (B)"). This makes it possible to provide a resin composition that has excellent storage stability and can be thermally cured at low temperatures. Any one of the thermal latent polymerization initiators may be used alone, or two or more may be used in combination.

[0035] The content of the thermal latent polymerization initiator (B) in the resin composition of this embodiment is preferably 0.5 to 60 parts by mass, more preferably 1 to 50 parts by mass, and even more preferably 1 to 40 parts by mass, per 100 parts by mass of the resin composition.

[0036] (C) Thermal Radical Initiator Desorption Accelerator The resin composition of this aspect may further include (C) a thermal radical initiator desorption accelerator (hereinafter also referred to as "component (C)"). In this specification, the term "(C) thermal radical initiator desorption accelerator" (hereinafter also simply referred to as "desorption accelerator") refers to a substance that can replace the thermal radical initiator supported on the inorganic ion exchanger in the thermal latent polymerization initiator, thereby promoting the desorption of the thermal radical initiator from the inorganic ion exchanger. The (C) desorption accelerator may be a Lewis basic substance or a Lewis acidic substance. For example, when the inorganic ion exchanger in the thermal latent polymerization initiator is an inorganic cation exchanger, a Lewis basic substance can be used as the (C) desorption accelerator. For example, when the inorganic ion exchanger in the thermal latent polymerization initiator is an inorganic anion exchanger, a Lewis acidic substance can be used as the (C) desorption accelerator. In one embodiment of this aspect, the (C) desorption accelerator is a Lewis basic substance. Examples of Lewis basic substances include, but are not limited to, water, amines, and imidazoles. In one embodiment of this aspect, the desorption promoter (C) is a Lewis acidic substance. Examples of Lewis acidic substances include, but are not limited to, water and fatty acids.

[0037] The content of the (C) elimination accelerator in the resin composition of this embodiment is preferably 0.001 to 60 parts by mass, more preferably 0.01 to 50 parts by mass, and even more preferably 0.1 to 40 parts by mass, per 100 parts by mass of the resin composition. Alternatively, the content of the (C) elimination accelerator in the resin composition of this embodiment is preferably 0.01 to 100 parts by mass, more preferably 0.1 to 90 parts by mass, and even more preferably 1 to 80 parts by mass, per 100 parts by mass of the (B) thermal latent polymerization initiator.

[0038] If desired, the resin composition of this embodiment may contain optional components other than the above components (A) to (C), such as those described below, as needed.

[0039] Polymerization Inhibitor The resin composition of this embodiment may contain a polymerization inhibitor. The polymerization inhibitor is a compound having radical scavenging ability. By containing a polymerization inhibitor, the progress of unintended radical polymerization reactions can be suppressed, and the storage stability of the resin composition can be further improved.

[0040] As the polymerization inhibitor, known polymerization inhibitors can be used, and examples thereof include, but are not limited to, N-nitroso-N-phenylhydroxylamine aluminum, triphenylphosphine, p-methoxyphenol, hydroquinone, p-benzoquinone, etc. In addition, known polymerization inhibitors disclosed in JP-A-2010-117545 and JP-A-2008-184514 can also be used. Any one of the polymerization inhibitors may be used alone, or two or more may be used in combination.

[0041] When the resin composition contains a polymerization inhibitor, the content of the polymerization inhibitor is preferably 0.1 to 5.0 parts by mass, more preferably 0.2 to 4.0 parts by mass, and even more preferably 0.3 to 3.0 parts by mass, relative to 100 parts by mass of the thermal latent polymerization initiator (B).

[0042] Filler The resin composition of this embodiment may contain a filler to the extent that the object of this embodiment is not impaired. By containing a filler in the resin composition, the linear expansion coefficient of the cured product obtained by curing the resin composition can be reduced, and thermal cycle resistance can be improved. Furthermore, if the filler has a low elastic modulus, stress generated in the cured product can be alleviated, and long-term reliability can be improved. Fillers are broadly classified into inorganic fillers and organic fillers.

[0043] The inorganic filler is not particularly limited as long as it is made of granular material formed from an inorganic material and has the effect of lowering the linear expansion coefficient when added. Examples of inorganic materials that can be used include silica, talc, zeolite, alumina, aluminum nitride, calcium carbonate, aluminum silicate, magnesium silicate, magnesium carbonate, barium sulfate, barium carbonate, lime sulfate, aluminum hydroxide, calcium silicate, potassium titanate, titanium oxide, zinc oxide, silicon carbide, silicon nitride, and boron nitride. One type of inorganic filler may be used, or two or more types may be used in combination. Silica filler is preferably used as the inorganic filler because it can increase the loading amount. Amorphous silica is preferred as the silica.

[0044] The inorganic filler is preferably one whose surface has been treated with a coupling agent such as a silane coupling agent, which allows the thixotropic index (TI) of the resin composition to fall within an appropriate range.

[0045] Furthermore, a conductive filler can also be used as the inorganic filler. The conductive filler may be a conductive material formed into particles, or a core (core particle) coated with a conductive material (coated powder). The core contained in the conductive filler may be made of a non-conductive material as long as a portion of it is coated with a conductive material. The conductive material in the conductive filler is not particularly limited as long as it imparts thermal conductivity and / or electrical conductivity to the resin composition. Examples include, but are not limited to, gold, silver, nickel, copper, palladium, platinum, bismuth, tin, and alloys thereof (particularly bismuth-tin alloys, solder, etc.), aluminum, indium tin oxide, silver-coated copper, silver-coated aluminum, metal-coated glass spheres, silver-coated fibers, silver-coated resin, antimony-doped tin, tin oxide, carbon fibers, graphite, carbon black, and mixtures thereof.

[0046] Examples of the organic filler include polytetrafluoroethylene (PTFE) filler, silicone filler, acrylic filler, styrene filler, etc. The organic filler may be surface-treated.

[0047] The shape of the filler is not particularly limited, and may be any of spherical, flaky, needle-like, irregular, etc.

[0048] The average particle size of the filler is preferably 0.01 to 15 μm, more preferably 0.01 to 10 μm, and the maximum particle size of the filler is preferably 50 μm or less, more preferably 30 μm or less.

[0049] In this specification, the average particle size of the filler is the particle size at 50% of the cumulative value in the particle size distribution on a volume basis measured by a laser diffraction / scattering method, and the maximum particle size is the maximum particle size in the particle size distribution on a volume basis measured by a laser diffraction / scattering method.

[0050] When a filler is contained, the content of the filler is preferably 0.5 to 80 mass %, more preferably 1 to 70 mass %, based on the total mass of the resin composition.

[0051] Other Additives If desired, the resin composition of this embodiment may further contain other additives, such as carbon black, titanium black, a thixotropic agent, a coupling agent, an ion trapping agent, a leveling agent, an antioxidant, an antifoaming agent, a viscosity modifier, a flame retardant, a colorant, a plasticizer, etc., within the scope of the present embodiment. The type and amount of each additive are as usual.

[0052] The viscosity of the resin composition of this embodiment is preferably 0.1 to 100 Pa·s. The viscosity can be adjusted appropriately depending on the application and application location of the resin composition. In this specification, viscosity is expressed as a value measured in accordance with Japanese Industrial Standard JIS K6833, unless otherwise specified. Specifically, it can be determined by measuring using an E-type viscometer at a rotation speed of 10 rpm. There are no particular limitations on the equipment, rotor, or measurement range used.

[0053] The method for producing the resin composition of this embodiment is not particularly limited. For example, the resin composition of this embodiment can be obtained by simultaneously or separately introducing component (A), component (B), and, if necessary, component (C) and other optional components into an appropriate mixer and mixing them by stirring to form a uniform composition. The mixer is not particularly limited, but examples that can be used include a Raikai mixer, a Henschel mixer, a three-roll mill, a ball mill, a planetary mixer, and a bead mill equipped with a stirring device and a heating device. These devices may also be used in appropriate combination.

[0054] The resin composition thus obtained is thermosetting and can be cured at low temperatures, for example, 40 to 120°C, preferably 50 to 100°C, more preferably 60 to 90°C, and even more preferably 60 to 80°C. Under conditions of a temperature of 80°C, it can be cured, for example, within 30 hours, for example, within 20 hours, preferably within 4 hours, more preferably within 3 hours, and even more preferably within 1 hour. When the resin composition of this embodiment is used to manufacture a semiconductor module containing components that deteriorate under high temperature conditions, it is preferable to thermally cure the composition at a temperature of 50 to 100°C for 15 minutes to 4 hours, preferably 30 minutes to 2 hours.

[0055] The resin composition of this embodiment can be used, for example, as an adhesive or sealant for fixing, joining or protecting components that constitute a semiconductor device or electronic component, or as a raw material thereof.

[0056] The method for applying the resin composition of this embodiment is not particularly limited, and for example, it can be supplied to a desired portion of a substrate or the like by a known printing method, dispensing method, or coating method. Printing methods include, but are not limited to, inkjet printing, screen printing, lithographic printing, carton printing, metal printing, offset printing, gravure printing, flexographic printing, etc. Dispensing methods include, but are not limited to, methods using a jet dispenser, an air dispenser, etc. Coating methods include, but are not limited to, dip coating, spray coating, bar coater coating, gravure coating, reverse gravure coating, spin coater coating, etc.

[0057] [Adhesive or Sealant] Another aspect of the present invention is an adhesive or sealant containing the resin composition of the above-described aspect. This adhesive or sealant enables good fixation, bonding, or protection of engineering plastics (e.g., LCP (liquid crystal polymer), polyamide, polycarbonate, etc.), ceramics, and metals (e.g., copper, nickel, etc.), and can be used to fix, bond, or protect components constituting a semiconductor device or electronic component. Examples of semiconductor devices or electronic components include, but are not limited to, HDDs, semiconductor elements, sensor modules such as image sensor modules, other semiconductor modules, and integrated circuits. The adhesive or sealant of this aspect can be cured under low-temperature conditions, allowing for high productivity and making it suitable for use, for example, in the manufacture of semiconductor devices and electronic components.

[0058] [Film] Another aspect of the present invention is a film containing the resin composition of the above-mentioned aspect. The film of this aspect can be used for electronic components, and is suitable as, for example, a coverlay film for protecting a wiring pattern, an interlayer adhesive film for a multilayer wiring board, or a prepreg.

[0059] The film of this embodiment can be obtained from the resin composition of the above embodiment by a known method. For example, the resin composition of the above embodiment can be diluted with a solvent to form a varnish, which can be applied to at least one surface of a support, dried, and then provided as a film attached to the support or a film peeled from the support.

[0060] Prepregs can be produced by known methods, such as hot melt and solvent methods. When using the hot melt method, the resin composition of the above embodiment is first coated on a release paper with good peelability without dissolving it in an organic solvent, and then laminated onto a sheet-like fiber substrate, or directly coated using a die coater, thereby producing a prepreg. When using the solvent method, the resin composition of the above embodiment is dissolved in an organic solvent, and the sheet-like fiber substrate is immersed in a resin composition varnish to impregnate the resin composition varnish into the sheet-like fiber substrate, and then the sheet-like fiber substrate is dried, thereby producing a prepreg.

[0061] [Cured Product of Resin Composition] Another aspect of the present invention is a cured product obtained by curing the resin composition of the above aspect. Such a cured product can be produced by heating the resin composition of the above aspect. A method for producing a cured product comprising heating the resin composition of the above aspect is also an aspect of the present invention. The heating temperature may be as low as 40 to 120°C, preferably 50 to 100°C, more preferably 60 to 90°C, and even more preferably 60 to 80°C. Under conditions of a temperature of 80°C, the heating time is, for example, within 30 hours, for example, within 20 hours, preferably 4 hours, more preferably within 3 hours, and even more preferably within 1 hour. In one embodiment, the heating conditions may be a temperature of 50 to 100°C and a heating time of 15 minutes to 4 hours, preferably 30 minutes to 2 hours.

[0062] [Semiconductor Device, Electronic Component] The semiconductor device or electronic component of one embodiment of the present invention includes the cured product of the above-described embodiment, and therefore has high reliability. Here, the term "semiconductor device" refers to any device that can function by utilizing semiconductor properties, and includes electronic components, semiconductor circuits, modules incorporating these, electronic devices, etc. Examples of semiconductor devices or electronic components include, but are not limited to, HDDs, semiconductor elements, sensor modules such as image sensor modules, other semiconductor modules, and integrated circuits.

[0063] The present invention will be described in more detail below with reference to Production Examples, Examples, and Comparative Examples, but the present invention is not limited to these Production Examples and Examples. In the following Production Examples and Examples, parts and % represent parts by mass and % by mass unless otherwise specified.

[0064] Experimental Example 1: Preparation of a thermal latent polymerization initiator [Preparation Example 1] 34.6 g of phosphoric acid (Fujifilm Wako Pure Chemical Industries, Ltd.) was diluted with purified water to 100 mL. 10.1 g of zirconium chloride octahydrate (Fujifilm Wako Pure Chemical Industries, Ltd.) was added and the mixture was allowed to react for 24 hours under reflux conditions. The resulting product was washed three times with purified water at 9,500 rpm using a centrifuge to obtain θ-ZrP. 6.09 g of the synthesized θ-ZrP (dry residue: 39.9%) was centrifuged three times with ethanol at 9,500 rpm using a centrifuge to replace the solvent with ethanol. Then, 32 mL of ethanol and 4.04 g of 2,2'-azobis[2-(2-imidazolin-2-yl)propane] (product name: VA-061, Fujifilm Wako Pure Chemical Industries, Ltd.) were added, and the mixture was allowed to react at room temperature for one day. The product was washed with ethanol eight times at 9,500 rpm using a centrifuge, and it was confirmed that no VA-061 remained in the supernatant, yielding thermal latent polymerization initiator 1 (ZrP-VA-061). Elemental analysis revealed C: 8.87, H: 2.13, and N: 4.41. The estimated composition was Zr(HPO ４ ) ２ 0.18C １２ H ２２ N ６ 0.63H ２O. Based on the amount of N, 0.53 mmol / g (13.1 wt %) of the thermal radical initiator (VA-061) was incorporated.

[0065] [Production Example 2] Zirconium propionate (8.38 g, 38.1 mmol) was dissolved in ethanol (100 mL), and phosphoric acid (12.0 mL) was added portionwise with vigorous stirring. The resulting transparent gel was centrifuged three times with ethanol (4000 rpm, 3 min) to obtain nanoparticulate zirconium phosphate. 82.0 g of the synthesized nanoparticulate zirconium phosphate (hereinafter also referred to as "NanoZrP") (dry weight 10.05%) was placed in an empty eggplant flask, and 6.65 g of 2,2'-azobis[2-(2-imidazolin-2-yl)propane] (product name: VA-061, Fujifilm Wako Pure Chemical Industries, Ltd.) dissolved in 50 mL of ethanol was added and stirred at room temperature for 1 hour. The product was then centrifuged three times with ethanol (4000 rpm, 3 min, 0°C) to obtain thermal latent polymerization initiator 2 (NanoZrP-VA-061). Elemental analysis revealed C: 19.75, H: 3.82, and N: 10.35. The estimated composition was Zr(HPO ４ ) ２ 0.55C １２ H ２２ N ６ 1.4H ２ O. Based on the amount of N, 1.23 mmol / g (30.8 wt %) of the thermal radical initiator (VA-061) was incorporated.

[0066] [Production Example 3] 2.00 g of powdered hydrotalcite (product name: DHT-6, Kyowa Chemical Industry Co., Ltd.), 1.17 g of 4,4'-azobis(4-cyanovaleric acid) (product name: V-501, Fujifilm Wako Pure Chemical Industries Co., Ltd.), and 32 mL of ethanol were weighed into an empty recovery flask and stirred for 24 hours. The mixture was then centrifuged at 9,500 rpm for 5 minutes, followed by washing with methanol three times to obtain thermal latent polymerization initiator 3 (hydrotalcite-V-501). Elemental analysis revealed a carbon content of 14.35, hydrogen content of 4.73, and nitrogen content of 2.82. The amount of nitrogen indicated that 0.50 mmol / g (14.1 wt%) of the thermal radical initiator (V-501) had been incorporated.

[0067] Experimental Example 2: Production and evaluation of resin compositions [Production of resin compositions] Resin compositions of the examples and comparative examples were prepared by mixing predetermined amounts of each component using a three-roll mill according to the formulations shown in Tables 1 and 2. In Tables 1 and 2, the amount of each component is expressed in parts by mass (unit: mg). The components used in the examples and comparative examples are as follows.

[0068] (A) Radically polymerizable compound (A-1): 2-hydroxyethyl methacrylate (manufactured by Tokyo Chemical Industry Co., Ltd.) (A-2): dimethylol-tricyclodecane diacrylate (Kyoeisha Chemical Co., Ltd. product name: Light Acrylate DCP-A) (B) Thermal latent polymerization initiator (B-1): Thermal latent polymerization initiator 1 of Production Example 1 (B-2): Thermal latent polymerization initiator 2 of Production Example 2 (B-3): Thermal latent polymerization initiator 3 of Production Example 3 (B') Radical polymerization initiator (B'-1): 2,2'-azobis[2-(2-imidazolin-2-yl)propane] (product name: VA-061, Fujifilm Wako Pure Chemical Industries, Ltd.) (C) Elimination accelerator (C-1): Water (C-2): Propylamine (C-3): Butylamine

[0069] In the examples and comparative examples, the properties of the resin compositions were measured as follows.

[0070] <Curability and Storage Stability> An oil bath was placed on a magnetic stirrer and set to the temperatures listed in Tables 1 and 2. Immediately after preparing each resin composition in the Examples and Comparative Examples, it was added to a 2 mL screw tube (glass bottle) containing a stir bar (Φ2 × 8 mm) and the bottle was capped. The prepared screw tube was placed in an oil bath, and the stir bar was rotated at a speed that could be seen with the naked eye. In Table 1, the time required for the stir bar to stop moving was taken as the curing time, and curability was evaluated. Furthermore, storage stability was confirmed visually by checking that the stir bar was rotating in the same manner as initially. In Table 2, cases where the composition was cured under the curing conditions shown in Table 2 were marked with "◎", and cases where the composition was not cured were marked with "×".

[0071]

[0072]

[0073] The disclosure of Japanese Patent Application No. 2024-010832 (filing date: January 29, 2024) is incorporated herein by reference in its entirety. All documents, patent applications, and technical standards mentioned herein are incorporated herein by reference to the same extent as if each individual document, patent application, and technical standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A thermal latent polymerization initiator in which a thermal radical initiator is supported on inorganic ion exchanger particles.

2. The thermal latent polymerization initiator according to claim 1, wherein the thermal radical initiator is an azo-based radical initiator.

3. The thermal latent polymerization initiator according to claim 1 or 2, wherein the inorganic ion exchanger is an inorganic cation exchanger.

4. The thermal latent polymerization initiator according to claim 3, wherein the inorganic cation exchanger is a phosphoric acid-based inorganic cation exchanger.

5. The thermal latent polymerization initiator according to claim 4, wherein the phosphate-based inorganic cation exchanger is zirconium phosphate.

6. A resin composition comprising (A) a radically polymerizable compound and (B) the thermal latent polymerization initiator described in any one of claims 1 to 5.

7. The resin composition according to claim 6, further comprising (C) a thermal radical initiator elimination accelerator.

8. The resin composition according to claim 7, wherein the (C) thermal radical initiator elimination accelerator is a Lewis basic substance.

9. An adhesive or sealant comprising the resin composition according to any one of claims 6 to 8.

10. A film comprising the resin composition according to any one of claims 6 to 8.

11. A cured product obtained by curing the resin composition according to any one of claims 6 to 8.

12. A method for producing a cured product, comprising heating the resin composition according to any one of claims 6 to 8.

13. A semiconductor device or electronic part comprising the cured product according to claim 11.

14. A method for producing a thermal latent polymerization initiator, comprising mixing a thermal radical initiator and an inorganic ion exchanger in the presence of a medium at a temperature lower than the 10-hour half-life temperature of the thermal radical initiator.

15. The method for producing a thermal latent polymerization initiator according to claim 14, wherein the thermal radical initiator is an azo-based radical initiator.

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