JP2020105343A - Curable resin composition, dry film, cured product, wiring board and electronic component - Google Patents

Abstract

To provide a curable resin composition excellent in low temperature curability and storage stability while keeping excellent characteristics such as adhesion, mechanical characteristics, chemical resistance, heat resistance and electric characteristics as a cured product of an epoxy resin, a dry film and a cured product using the curable composition, and a wiring board and an electronic component using the cured product.SOLUTION: There are provided a curable resin composition containing an epoxy resin, a diamine compound and a cellulose nanofiber, a dry film and a cured product using the curable composition, and a wiring board and an electronic component using the cured product.SELECTED DRAWING: None

Description

The present invention relates to a curable resin composition containing an epoxy resin, a dry film, a cured product, a wiring board, and an electronic component.

Epoxy resin is a coating material, an adhesive agent, since a cured product excellent in various properties such as adhesiveness, mechanical properties, water resistance, chemical resistance, heat resistance, and electrical insulation properties can be obtained by curing it. It is used in a wide range of technical fields such as composite materials, molding materials, casting materials, various coating materials, and printed wiring boards such as interlayer insulation materials and solder resists.

In particular, for printed wiring board materials, curable resin compositions containing this epoxy resin are required to have even more excellent properties as the wiring board becomes multifunctional. For example, as component mounting of wiring boards and wiring density and thinning progress, curable resin compositions containing this epoxy resin have high electrical insulation, high thermal conductivity, and low thermal expansion coefficient (thermal dimension). Stability) and excellent flame retardancy.

On the other hand, in recent years, as a material for a wiring board, in addition to a glass epoxy substrate (FR-4) and a polyimide substrate which are excellent in heat resistance, polyethylene terephthalate (PET) and the like have low heat resistance, but also have high transparency and are inexpensive materials. Has been adopted. In a printed wiring board made of such a material having low heat resistance, a curable resin composition containing an epoxy resin cures at a low temperature in a short time (excellent low temperature curability), and has excellent storage stability at room temperature. Is required.

On the other hand, hitherto, there has been proposed a latent curing agent which has been made latent by coating a curing agent component of an epoxy resin with a film, and an epoxy resin composition containing the latent curing agent (see Patent Document 1). ..

JP, 2005-344046, A

However, in the latent curing agent and the resin composition described in Patent Document 1, there is still room for improvement in the curing latency in order to be put to practical use, and the latent curing agent increases the cost and cures the curing. It was necessary to adjust the production method and the components of the composition so that the film coating the agent was not dissolved or destroyed.

Therefore, an object of the present invention is to maintain the adhesiveness as the original cured product of the epoxy resin, mechanical properties, chemical resistance, heat resistance, and excellent properties such as electrical insulation without using a latent curing agent. To provide a curable resin composition that is simple and obtains excellent low-temperature curability and storage stability, a dry film and a cured product using the curable composition, a wiring board and an electronic component using the cured product. It is in.

The present inventors, for the achievement of the above objects, as a result of diligent study focusing on the curing system of the epoxy resin and the diamine compound, which are excellent in low-temperature curability, surprisingly, by blending cellulose nanofibers as a filler, cellulose The inventors have found that nanofibers can suppress the reaction between the epoxy resin and the diamine compound at room temperature, and have completed the present invention.

That is, the present invention is a curable resin composition containing an epoxy resin, a diamine compound, and cellulose nanofibers.

The diamine compound may include either an aromatic diamine compound or an alicyclic diamine compound.

Further, the present invention provides a dry film, characterized in that the curable resin composition has a resin layer formed by coating and drying the curable resin composition on the film.

Further, the present invention provides a cured product, which is obtained by curing the curable resin composition or the dry film.

Further, the present invention provides a wiring board including the cured product.

The present invention also provides an electronic component comprising the cured product.

According to the present invention, while maintaining excellent properties such as adhesiveness and mechanical properties as an epoxy resin original cured product, chemical resistance, heat resistance, and electrical properties, it is simple without using a latent curing agent, and It is possible to provide a curable resin composition that can obtain excellent low-temperature curability and storage stability, a dry film and a cured product using the curable composition, a wiring board and an electronic component using the cured product.

In addition, when an isomer exists in the compound described, all possible isomers can be used in the present invention unless otherwise specified.

In addition, the mass of the solid content in this specification means the mass of the residue in which the volatile components are completely volatilized.

<<<Curable resin composition>>
The curable resin composition according to the present invention includes an epoxy resin, a diamine compound, and cellulose nanofibers (may be abbreviated as CNF).

The curable resin composition according to the present invention will be described in detail below.

<<Curable resin>>
The curable resin composition according to the present invention contains an epoxy resin as a thermosetting resin.

The epoxy resin according to the present invention is not particularly limited. Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol E type epoxy resin, bisphenol M type epoxy resin, bisphenol P type epoxy resin, and bisphenol Z type epoxy resin. Epoxy resin, bisphenol A novolac type epoxy resin, phenol novolac type epoxy resin, cresol novolac epoxy resin and other novolac type epoxy resin, biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, aryl alkylene type epoxy resin, tetraphenylol ethane type epoxy resin Resin, naphthalene type epoxy resin, anthracene type epoxy resin, phenoxy type epoxy resin, dicyclopentadiene type epoxy resin, norbornene type epoxy resin, trihydroxyphenylmethane type epoxy resin, hydantoin type epoxy resin, tetraphenylolethane type epoxy resin, Brominated epoxy resin, hydrogenated (bisphenol) type resin, glycidyl amine type epoxy resin, alicyclic epoxy resin, diglycidyl phthalate resin, tetraglycidyl xylenoyl ethane resin, glycidyl methacrylate copolymer epoxy resin, cyclohexyl maleimide Copolymerized epoxy resin with glycidyl methacrylate, epoxy modified polybutadiene rubber derivative, CTBN modified epoxy resin, trimethylolpropane polyglycidyl ether, phenyl-1,3-diglycidyl ether, 1,6-hexanediol diglycidyl ether, ethylene Examples thereof include epoxy resins such as diglycidyl ether of glycol or propylene glycol, sorbitol polyglycidyl ether, tris(2,3-epoxypropyl)isocyanurate, and triglycidyl tris(2-hydroxyethyl)isocyanurate.

Examples of commercially available epoxy resins include jER828, jER834, jER1001, jER1004 manufactured by Mitsubishi Chemical Corporation, Epicron 840, Epicron 850, Epicron 1050, Epicron 2055, and Epotote manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. YD-011, YD-013, YD-127, YD-128, D.I. E. R. 317, D.I. E. R. 331, D.I. E. R. 661, D.I. E. R. 664, Sumitomo Chemical Co., Ltd. Sumi-epoxy ESA-011, ESA-014, ELA-115, ELA-128, A.A. E. R. 330, A. E. R. 331, A.A. E. R. 661, A.D. E. R. Bisphenol A type epoxy resin such as 664 (both are trade names); jERYL903 manufactured by Mitsubishi Chemical Corporation, Epicron 152, Epicron 165 manufactured by DIC Corporation, Epotote YDB-400, YDB-500 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. D. made by Dow Chemical Company. E. R. 542, Sumi-epoxy ESB-400 and ESB-700 manufactured by Sumitomo Chemical Co., Ltd., and A.E. manufactured by Asahi Kasei Corporation. E. R. 711, A. E. R. Brominated epoxy resin such as 714 (all trade names); jER152 and jER154 manufactured by Mitsubishi Chemical Co., and D.I. E. N. 431, D.I. E. N. 438, Epicron N-730, Epicron N-770, Epicron N-865 manufactured by DIC Corporation, Epototo YDCN-701, YDCN-704 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., EPPN-201 manufactured by Nippon Kayaku Co., Ltd., EOCN-1025, EOCN-1020, EOCN-104S, RE-306, Sumi-epoxy ESCN-195X, ESCN-220 manufactured by Sumitomo Chemical Co., Ltd., A.A. E. R. Novolak type epoxy resins such as ECN-235 and ECN-299 (both are trade names); Epicron 830 manufactured by DIC Corporation, jER807 manufactured by Mitsubishi Chemical Corporation, Epototo YDF-170, YDF-175 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. , YDF-2004 etc. (both are trade names) Bisphenol F type epoxy resin; hydrogenated bisphenol A type epoxy resins such as Epototo ST-2004, ST-2007, ST-3000 (trade names) manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. Glycidylamine type epoxy resin such as jER604 manufactured by Mitsubishi Chemical Co., Ltd., Epototo YH-434 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd., Sumi-epoxy ELM-120 manufactured by Sumitomo Chemical Co., Ltd. (both are trade names); hydantoin type Epoxy resin; alicyclic epoxy resin such as Celoxide 2021P (trade name) manufactured by Daicel Co., Ltd.; YL-933 manufactured by Mitsubishi Chemical Co., Ltd.; E. N. , EPPN-501, EPPN-502, etc. (all are trade names), trihydroxyphenylmethane type epoxy resin; Mitsubishi Chemical Co. YL-6056, YX-4000, YL-6121 (all are trade names), etc. Xylenol type or biphenol type epoxy resin or mixture thereof; bisphenol S type epoxy such as EBPS-200 manufactured by Nippon Kayaku Co., EPX-30 manufactured by Asahi Denka Co., Ltd., EXA-1514 (trade name) manufactured by DIC Co., Ltd. Resin: bisphenol A novolac type epoxy resin such as jER157S (trade name) manufactured by Mitsubishi Chemical Co.; tetraphenylolethane type epoxy resin such as jERYL-931 manufactured by Mitsubishi Chemical Co. (trade name); Nissan Chemical Industry Heterocyclic epoxy resins such as TEPIC (trade name) manufactured by Co., Ltd.; diglycidyl phthalate resins such as BLEMMER DGT manufactured by NOF CORPORATION; tetraglycidyl xylenoylethane resins such as ZX-1063 manufactured by Nippon Steel & Sumitomo Metal Corporation; Naphthalene group-containing epoxy resins such as ESN-190, ESN-360 manufactured by Nippon Steel Chemical Co., Ltd., HP-4032 manufactured by DIC Co., Ltd., EXA-4750, and EXA-4700; HP-7200 manufactured by DIC Co., Ltd., HP-7200H, etc. Epoxy resin having cyclopentadiene skeleton; CP-50S, CP-50M and other glycidyl methacrylate copolymerization epoxy resins manufactured by NOF CORPORATION; and further, cyclohexylmaleimide and glycidyl methacrylate copolymerization epoxy resin; epoxy-modified polybutadiene rubber derivative (For example, PB-3600 manufactured by Daicel Chemical Industries, Ltd.), CTBN-modified epoxy resin (for example, YR-102, YR-450 manufactured by Tohto Kasei Co., Ltd.), and the like. These epoxy resins may be used alone or in combination of two or more. Can be used in combination, from the viewpoint of excellent low temperature curability and storage stability of the curable resin composition, an epoxy resin having an alicyclic structure or an aromatic structure, having an alicyclic structure, or It is preferable to use an epoxy group-containing monomer or oligomer having an aromatic structure, and an epoxy resin having an alicyclic structure is more preferable.

The content of the epoxy resin may be, for example, 50% by mass or more, 90% by mass or more, 95% by mass or more, 99% by mass or more with respect to the total thermosetting resin. Alternatively, it may be 1 mass% or more and 90 mass% or less, 10 mass% or more and 85 mass% or less, 20 mass% or more and 80 mass% or less, and the like.

<<Curing agent>>
The curable resin composition according to the present invention contains a diamine compound as a curing agent.

The diamine compound according to the present invention is not particularly limited. Examples of the diamine compound include chain aliphatic diamine compounds such as ethylenediamine, propylenediamine, trimethylenediamine, tetramethylenediamine, and hexamethylenediamine; 1,3-diaminocyclohexane, isophoronediamine, mensendiamine, 4,4′. -Methylenedicyclohexanediamine (hydrogenated methylenedianiline), 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro[5,5]undecane, piperazine, N-aminoethylpiperazine Alicyclic diamine compounds such as 1,4-diaminoethylpiperazine and 1,4-bis(2-amino-2-methylpropyl)piperazine; 1,2-, 1,3- or 1,4-phenylenediamine, 2,4'- or 4,4'-diphenylmethanediamine, diaminodiphenylsulfone, benzidine, thiodianiline, bis(3,4-diaminophenyl)sulfone, 2,6-diaminopyridine, m-aminobenzylamine, naphthylenediamine, 2,4- or 2,6-tolylenediamine, crude tolylenediamine, diethyltolylenediamine, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 4,4'-diamino-3,3'- Diethyldiphenylmethane, 4,4'-bis(o-toluidine), dianisidine, diaminoditolyl sulfone, 1,3-dimethyl-2,4-diaminobenzene, 1,3-diethyl-2,4-diaminobenzene, 1, 3-dimethyl-2,6-diaminobenzene, 1,4-diethyl-2,5-diaminobenzene, 1,4-diisopropyl-2,5-diaminobenzene, 1,4-dibutyl-2,5-diaminobenzene, 2,4-diaminomesitylene, 1,3,5-triethyl-2,4-diaminobenzene, 1,3,5-triisopropyl-2,4-diaminobenzene, 1-methyl-3,5-diethyl-2, 4-diaminobenzene, 1-methyl-3,5-diethyl-2,6-diaminobenzene, 2,3-dimethyl-1,4-diaminonaphthalene, 2,6-dimethyl-1,5-diaminonaphthalene, 2, 6-diisopropyl-1,5-diaminonaphthalene, 2,6-dibutyl-1,5-diaminonaphthalene, 3,3′,5,5′-tetramethylbenzidine, 3,3′,5,5′-tetraisopropyl Benzidine, 3,3',5,5'-tetramethyl-4,4'-diaminodiphenylmethane, 3,3',5,5'-teto Raethyl-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetraisopropyl-4,4'-diaminodiphenylmethane, 3,3',5,5'-tetrabutyl-4,4'-diaminodiphenylmethane , 3,5-diethyl-3'-methyl-2',4-diaminodiphenylmethane, 3,5-diisopropyl-3'-methyl-2',4-diaminodiphenylmethane, 3,3'-diethyl-2,2' -Diaminodiphenylmethane, 4,4'-diamino-3,3'-dimethyldiphenylmethane, 3,3',5,5'-tetraethyl-4,4'-diaminobenzophenone, 3,3',5,5'-tetra Isopropyl-4,4'-diaminobenzophenone, 3,3',5,5'-tetraethyl-4,4'-diaminodiphenyl ether, 3,3',5,5'-tetraisopropyl-4,4'-diaminodiphenyl An aromatic diamine compound such as sulfone can be used, and these can be used alone or in combination of two or more kinds. The diamine compound preferably contains an alicyclic diamine compound or an aromatic diamine compound from the viewpoint of low-temperature curability and storage stability of the curable resin composition.

As the content of the diamine compound, amine equivalent/epoxy equivalent is preferably 0.7 to 1.4, and more preferably 0.8 to 1.2. Within such a range, the curable resin composition can have excellent low temperature curability and storage stability.

The curable resin composition according to the present invention may contain other curing agent other than the diamine compound as long as the effect of the present invention is not impaired. Other curing agents include phenol resins such as phenol novolac resin, cresol novolac resin, bisphenol A novolac resin and resol type phenol resin; acid anhydrides; aliphatic polyamines, melamine, dicyandiamide, polyaminoamide (polyamide resin), ketimine, Amine compounds other than diamine compounds, such as amine compounds (imidazole, tertiary amine, polyamine compounds); mercaptan compounds; active ester resins; resins having a benzoxazine ring; Lewis acid complex compounds, and modified products thereof. Can be mentioned.

<<Cellulose Nanofiber (CNF)>>
The curable resin composition according to the present invention contains CNF.

The CNF according to the present invention is not particularly limited. As CNF, for example, mechanically defibrated CNF; 2,2,6,6-tetramethylpiperidine 1-oxyl (also referred to as TEMPO), or a compound having a phosphoric acid group and/or an amino acid after oxidation treatment with a salt thereof is used. CNF which has been covalently modified with a compound to be defibrated, or CNF which has been subjected to ionic bond modification with a quaternary ammonium compound to be defibrated such as CNF after being subjected to the above-mentioned oxidation treatment; Among these, CNF subjected to hydrophobic treatment is preferable because it has excellent dispersibility in a resin hydrophobic substance and a curable resin composition can have excellent low-temperature curability and storage stability.

In the present invention, the average fiber diameter of CNF is, for example, 0.1 nm or more and 200 nm or less, preferably 1 nm or more and 100 nm or less, more preferably 2 nm or more and 50 nm or less, and further preferably 2.5 nm or more and 20 nm or less. When the average fiber diameter is in such a range, a cured product having excellent adhesion to the conductor of the wiring board and the like can be obtained.

The average fiber length of CNF is, for example, 600 nm or less, preferably 50 nm or more and 600 nm or less, more preferably 100 nm or more and 500 nm or less, and further preferably 100 nm or more and 400 nm or less. When the average fiber length is 600 nm or less, the dispersion of the composition becomes easy. The higher dispersibility allows the curable resin composition to have excellent low temperature curability and storage stability.

The average aspect ratio of CNF is, for example, 1 or more and 200 or less, preferably 5 or more and 180 or less, more preferably 9 or more and 170 or less, and particularly preferably 9 or more and less than 100. If the average aspect ratio is less than 1, it is difficult to produce, and if the average aspect ratio is 200 or less, the adhesion between the metal conductor and the cured product becomes good, and the smaller the average aspect ratio, the more the metal conductor and the cured product become. The adhesiveness is excellent and the viscosity of the composition can be reduced.

The average fiber diameter, average fiber length, and average aspect ratio of CNF can be measured as follows.

Water was added to CNF to prepare a dispersion having a concentration of 0.0001% by mass, and the dispersion was dropped on mica (mica) and dried, and an observation sample was used as an atomic force microscope (AFM, Nanoscope III Tapping mode AFM, manufactured by Digital instrument, using Nano Probes manufactured by Nanosensors as a probe) to measure the fiber height of CNF in the observed sample. At that time, 5 or more CNFs are extracted from the microscope image in which the CNFs can be confirmed, and the average fiber diameter is calculated from the fiber heights thereof. Further, the average fiber length is calculated from the distance in the fiber direction. The average aspect ratio is calculated from the average fiber length/average fiber diameter.

The method for producing the CNF is not particularly limited, and a known method can be used.

As a method for producing mechanically defibrated CNF, there can be mentioned a method in which cellulose fibers are swollen with water in a large amount of water, and in a softened state, they are nano-sized by powerful mechanical pulverization using a high pressure homogenizer or the like.

A method disclosed in JP-A-2018-24878 can be mentioned as a method for producing the hydrophobically-treated CNF.

Even if the hydrophobic treatment is performed, the average fiber diameter, average fiber length and average aspect ratio of CNF are maintained.

The content of CNF in the curable resin composition of the present invention is preferably 0.1 parts by mass or more and 30 parts by mass or less, more preferably 1 part by mass with respect to 100 parts by mass of the total amount of the curable resin (solid content basis). Parts to 20 parts by mass, more preferably 2 parts to 10 parts by mass. When the content is 0.1 parts by mass or more, the film-forming property of the curable resin composition becomes high, and when the content is 30 parts by mass or less, the curable resin composition has excellent low temperature curability and storage stability. You can

<Other ingredients>
The curable resin composition according to the present invention may be added with other components other than the above-mentioned essential components, for example, conventional additives depending on the use. Other conventional additives are not particularly limited, and examples thereof include resins and elastomers, fillers other than CNF (organic fillers, inorganic fillers), curing catalysts, colorants, dispersants, defoaming agents/leveling agents, thixotropic agents. Agents, coupling agents, flame retardants and the like. Further, the curable resin composition according to the present invention may contain an organic solvent and the like, if necessary.

(Resin and elastomer)
The resin and the elastomer are resin components other than the above-mentioned curable resin and curing agent, and are unsaturated polyester resin, acrylate resin, diallyl phthalate resin, silicone resin, norbornene resin, isocyanate resin, urethane resin, benzocyclobutene resin, Examples thereof include polyazomethine resin, block copolymer, natural rubber, diene rubber, non-diene rubber, and thermoplastic elastomer.

(Inorganic filler)
As the inorganic filler, barium sulfate, barium titanate, amorphous silica, crystalline silica, fused silica, spherical silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, alumina, silicon nitride, boron nitride , Aluminum nitride and the like. These inorganic fillers can be used alone or in combination. Among these inorganic fillers, silica is preferable, and spherical silica is preferable, because it has a low specific gravity, can be incorporated in a composition at a high ratio, and has a low thermal expansion property. The average particle size of the inorganic filler is preferably 3 μm or less, more preferably 1 μm or less. The average particle size of the inorganic filler can be determined by a laser diffraction particle size distribution measuring device.

The content of the inorganic filler is, for example, 25% by mass to 90% by mass, preferably 30% by mass to 90% by mass, and more preferably 35% by mass to 85% by mass, based on the solid content of the composition. By setting the content of the inorganic filler within the above range, it is possible to ensure good coating film performance of the cured product after curing.

(Curing catalyst)
The curing catalyst is mainly for curing a thermosetting resin among curable resins, and includes, for example, imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, and 2-ethylimidazole. Imidazole derivatives such as phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; dicyandiamide, benzyldimethylamine, 4-(dimethylamino) Amine compounds such as -N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, 4-methyl-N,N-dimethylbenzylamine; hydrazine compounds such as adipic acid dihydrazide and sebacic acid dihydrazide; tri Examples thereof include phosphorus compounds such as phenylphosphine and dimethylaminopyridine. Moreover, as a commercial item, for example, 2MZ-A, 2MZ-OK, 2PHZ, 2P4BHZ, 2P4MHZ (manufactured by Shikoku Chemicals Co., Ltd.), U-CAT3503N, U-CAT3502T, DBU, DBN, U-CATSA102, U-. Examples thereof include CAT5002 (manufactured by San-Apro Co., Ltd.), which may be used alone or in combination of two or more kinds. Similarly, guanamine, acetoguanamine, benzoguanamine, melamine, 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6. S-triazine derivatives such as -diamino-S-triazine/isocyanuric acid adduct and 2,4-diamino-6-methacryloyloxyethyl-S-triazine/isocyanuric acid adduct can also be used. These curing catalysts can be used alone or in combination.

The content of the curing catalyst is, for example, 20 parts by mass or less, preferably 15 parts by mass or less, and more preferably 15 parts by mass or less with respect to 100 parts by mass of the total thermosetting resin.

It is preferable not to include a curing catalyst. When a curing catalyst is included, the low temperature curability is excellent, but the storage stability may be reduced.

(Colorant)
Examples of the colorant include those having a color index (C.I.; issued by The Society of Dyers and Colorists) as a color pigment or dye. Examples of the red colorant include monoazo, diazozo, azo lake, benzimidazolone, perylene, diketopyrrolopyrrole, condensed azo, anthraquinone, and quinacridone. Examples of the blue colorant include phthalocyanine-based and anthraquinone-based colorants, and pigment-based compounds that can be used include compounds classified as pigments. Besides these, metal-substituted or unsubstituted phthalocyanine compounds can also be used. Similarly, green colorants include phthalocyanine type, anthraquinone type, and perylene type. Besides these, metal-substituted or unsubstituted phthalocyanine compounds can also be used. Examples of yellow colorants include monoazo type, disazo type, condensed azo type, benzimidazolone type, isoindolinone type and anthraquinone type. Examples of the white colorant include rutile type or anatase type titanium oxide. Examples of black colorants include carbon black, graphite, iron oxide, titanium black, iron oxide, anthraquinone, cobalt oxide, copper oxide, manganese, antimony oxide, nickel oxide, perylene, aniline. System, molybdenum sulfide, bismuth sulfide, etc. In addition, colorants such as purple, orange and brown may be added for the purpose of adjusting the color tone.

(Dispersant)
Examples of the dispersant include polycarboxylic acid type, naphthalene sulfonic acid formalin condensation type, polyethylene glycol, polycarboxylic acid partial alkyl ester type, polyether type, polyalkylene polyamine type and the like polymer type dispersant, alkyl sulfonic acid type, A low molecular type dispersant such as a primary ammonium type, a higher alcohol alkylene oxide type, a polyhydric alcohol ester type or an alkyl polyamine type can be used, a sufficient dispersing effect can be obtained, and further a good coating property of a cured product can be obtained. be able to.

(Antifoaming agent/Leveling agent)
As the antifoaming agent/leveling agent, compounds such as silicone, modified silicone, mineral oil, vegetable oil, aliphatic alcohol, fatty acid, metal soap, fatty acid amide, polyoxyalkylene glycol, polyoxyalkylene alkyl ether, polyoxyalkylene fatty acid ester, etc. Etc. can be used, the generation of voids can be prevented, and the adhesion to the adherend becomes better.

(Thixotropic agent)
As the thixotropic agent, fine particle silica, silica gel, amorphous inorganic particles, polyamide-based additive, modified urea-based additive, wax-based additive, etc. can be used, and the curability of the curable resin composition is improved, and the coating property is improved. The adhesion of the film to the adherend becomes excellent.

(Coupling agent)
The coupling agent is a methoxy group, an ethoxy group, acetyl or the like as an alkoxy group, and a vinyl, methacryl, acryl, epoxy, cyclic epoxy, mercapto, amino, diamino, acid anhydride, ureido, sulfide as a reactive functional group. Isocyanates and the like, for example, vinyl silane, vinyltrimethoxysilane, vinyltrimethoxysilane, vinyl tris(β-methoxyethoxy)silane, γ-methacryloxypropyltrimethoxylane and the like, γ-aminopropyltrimethoxylane, Amino-based silane compounds such as N-β-(aminoethyl)γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)γ-aminopropylmethyldimethoxysilane, and γ-ureidopropyltriethoxysilane, γ-glycid Epoxy-based silane compounds such as xypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxylane, γ-glycidoxypropylmethyldiethoxysilane, and mercapto-based silanes such as γ-mercaptopropyltrimethoxysilane. Compounds, silane coupling agents such as phenylamino silane compounds such as N-phenyl-γ-aminopropyltrimethoxysilane, isopropyltriisostearoylated titanates, tetraoctylbis(ditridecylphosphite) titanates, bis(dioctylpyrophosphate) ) Oxyacetate titanate, isopropyl tridodecylbenzene sulfonyl titanate, isopropyl tris(dioctyl pyrophosphate) titanate, tetraisopropyl bis(dioctyl phosphite) titanate, tetra(1,1-diallyloxymethyl-1-butyl)bis-(ditridecyl) Phosphite titanate, bis(dioctyl pyrophosphate) ethylene titanate, isopropyl trioctanoyl titanate, isopropyl dimethacryl isostearoyl titanate, isopropyl tristearoyl diacrylic titanate, isopropyl tri(dioctyl phosphate) titanate, isopropyl tricumylphenyl titanate, dicumylphenyl Titanate coupling agents such as oxyacetate titanate and diisostearoyl ethylene titanate, ethylenically unsaturated zirconate containing compounds, neoalkoxy zirconate containing compounds, neoalkoxy tris neodecanoyl zirconate, neoalkoxy tris(dodecyl) Benzenesulfonyl zirconate, neoalkoxy tris(dioctyl)phosphate zirconate, neoalkoxy tris(dioctyl)pyrophosphate zirconate, neoalkoxy tris(ethylenediamino)ethyl zirconate, neoalkoxy tris(m-amino)phenyl zirconate, tetra (2,2-diallyloxymethyl)butyl, di(ditridecyl)phosphite zirconate, neopentyl(diallyl)oxy, trineodecanoyl zirconate, neopentyl(diallyl)oxy, tri(dodecyl)benzene-sulfonyl zirconate, neopentyl (Diallyl)oxy, tri(dioctyl)phosphato zirconate, neopentyl(diallyl)oxy, tri(dioctyl)pyro-phosphato zirconate, neopentyl(diallyl)oxy, tri(N-ethylenediamino)ethyl zirconate, neopentyl( Diallyl)oxy, tri(m-amino)phenyl zirconate, neopentyl(diallyl)oxy, trimethacryl zirconate, neopentyl(diallyl)oxy, triacryl zirconate, dineopentyl(diallyl)oxy, diparaaminobenzoyl zirconate, dineopentyl( Diallyl)oxy, di(3-mercapto)propionic zirconate, zirconium (IV)2,2-bis(2-propenolatomethyl)butanolato,cyclodi[2,2-(bis2-propenolatomethyl) Butanolato]pyrophosphato-O, O and other zirconate-based coupling agents, diisobutyl (oleyl) acetoacetylaluminate, alkyl acetoacetate aluminum diisopropylate and other aluminate-based coupling agents can be used, and adhesion to the substrate And the hardness of the cured product can be expected to improve.

(Flame retardants)
Examples of flame retardants include hydrated metal compounds such as aluminum hydroxide and magnesium hydroxide, red phosphorus, ammonium phosphate, ammonium carbonate, zinc borate, zinc stannate, molybdenum compound system, bromine compound system, chlorine compound system, phosphate ester. , Phosphorus-containing polyols, phosphorus-containing amines, melamine cyanurates, melamine compounds, triazine compounds, guanidine compounds, silicon polymers, etc. can be used, and self-extinguishing properties and heat resistance of cured products can be achieved at a high level in a well-balanced manner.

(Organic solvent)
Examples of the organic solvent include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, diethylene glycol. Glycol ethers such as monoethyl ether, dipropylene glycol monoethyl ether and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, cellosolve acetate, diethylene glycol monoethyl ether acetate and esterified products of the above glycol ethers; Alcohols such as ethanol, propanol, ethylene glycol, propylene glycol; amides such as dimethylformamide and dimethylacetamide; aliphatic hydrocarbons such as octane and decane; petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, solvent naphtha, etc. Examples include petroleum-based solvents.

The content of the organic solvent is not particularly limited and can be appropriately adjusted depending on the application of the curable composition.

<<<<Dry film>>>>
The dry film of the present invention is a resin layer obtained by applying or impregnating the above-mentioned curable composition on a substrate and drying the same.

Here, examples of the substrate include metal foil such as copper foil, polyimide film, polyester film, film such as polyethylene naphthalate (PEN) film, glass cloth, and fiber such as aramid fiber.

The dry film can be obtained, for example, by applying a curable composition on a polyethylene terephthalate film, drying it, and laminating a polypropylene film as necessary.

<<< cured product >>>
The cured product is obtained by curing the curable composition described above (including the resin layer contained in the dry film).

The method for obtaining a cured product from the curable composition is not particularly limited and can be appropriately changed depending on the composition of the curable composition. As an example, after performing a step of coating a curable composition on the above-mentioned substrate (for example, coating with an applicator), a drying step of drying the curable composition as necessary is performed. Then, the curable resin may be cured by heating (for example, heating by an inert gas oven, a hot plate, a vacuum oven, a vacuum press, or the like) and a heat curing step of thermally crosslinking the curing agent. The conditions for implementation in each step (for example, coating thickness, drying temperature and time, heating temperature and time, etc.) may be appropriately changed according to the composition and application of the curable composition.

<<< wiring board, electronic parts >>>
Since such a cured product has excellent mechanical properties, heat resistance, and transparency, it can be used for electronic parts and the like. In particular, it is used as an interlayer insulating film or a solder resist in a printed wiring board, or as an encapsulant for light emitting diodes in optical electronic parts.

Hereinafter, the present invention will be described in more detail with reference to examples. In addition, all the compounding amounts in the following tables indicate parts by mass.

<Preparation of Cellulose Nanofiber Dispersion>
(CNF) 100 g of hardwood bleached kraft pulp (manufactured by CENIBRA) fibers were sufficiently stirred with 9900 g of ion-exchanged water, and then TEMPO (manufactured by ALDRICH, free radical, 98 mass%) per 100 g of this pulp. 25 mass%, sodium bromide 12.5 mass%, and sodium hypochlorite 28.4 mass% were added in this order. The pH was maintained at 10.5 by the dropwise addition of 0.5 M sodium hydroxide using a pH stud. After the reaction was performed for 120 minutes (20° C.), the dropping of sodium hydroxide was stopped to obtain oxidized pulp. The oxidized pulp obtained by using ion-exchanged water was thoroughly washed and then dehydrated to obtain oxidized pulp having a solid content of 30.4%.
The obtained 105.3 g of oxidized pulp was diluted with 1000 g of ion-exchanged water, and 346 g of concentrated hydrochloric acid was added to prepare a dispersion liquid of oxidized pulp solid content concentration 2.34 wt% and hydrochloric acid concentration 2.5 M. Reflux for minutes. Then, the oxidized pulp was thoroughly washed to obtain acid-hydrolyzed TEMPO oxidized pulp having a solid content of 41%. Then, 0.88 g of oxidized pulp and 35.12 g of ion-exchanged water were subjected to a micronization treatment 10 times at 150 MPa using a high-pressure homogenizer to obtain a carboxyl group-containing fine cellulose fiber dispersion liquid (solid content concentration 5.0 mass%). It was This fine cellulose fiber had an average fiber diameter of 11.0 nm, an average fiber length of 187 nm, an average aspect ratio of 17, and a carboxyl group content of 1.1 mmol/g.
Next, the fine cellulose fiber dispersion was charged into a beaker equipped with a magnetic stirrer and a stirrer. Subsequently, dodecylamine was added in an amount corresponding to 1.2 mol of amino groups with respect to 1 mol of carboxyl groups of the fine cellulose fiber, 0.34 g of 4-methylmorpholine, and 4-(4,6-dimethoxy-1,4,6-dimethoxy-1,6) as a condensing agent. 1.98 g of 3,5-triazin-2-yl)-4-methylmorpholinium chloride (hereinafter referred to as DMT-MM) was charged and dissolved in 300 g of N,N-dimethylformamide (hereinafter referred to as DMF). .. The reaction solution was reacted at room temperature (25°C) for 14 hours. After completion of the reaction, filtration, washing with ethanol, removal of DMT-MM salt, washing with DMF and solvent replacement, CNF/DMF in which aliphatic hydrocarbon groups are linked to the fine cellulose fibers via amide bonds A dispersion was obtained. The solid content concentration of the obtained CNF/DMF dispersion was 2.2% by mass.

<Preparation of curable resin composition>
After blending and stirring each component according to the description in Table 1 below, a high pressure homogenizer Nanowater NVL-ES008 manufactured by Yoshida Kikai Kogyo Co., Ltd. was used and dispersed 6 times to prepare each composition. In addition, the numerical value in Table 1 shows the mass part of solid content (excluding volatile components).

<Storage stability>
Each of the obtained samples was measured for the viscosity of 1 g of each composition using a V-type viscometer TPE-100 manufactured by Toki Sangyo Co., Ltd., and then allowed to stand at room temperature for 1 week, and the viscosity was measured again. A product whose viscosity change after standing for 1 week was less than 1.5 times was evaluated as ⊚, 1.5 times or more and less than 2 times was evaluated as ∘, 2 times or more and less than 3 times was evaluated as ◯, and 3 times or more was evaluated as x.

<Low temperature curability>
2 mg of each obtained sample was measured under a nitrogen atmosphere from DSC Q100 manufactured by TA Instruments at a temperature rising rate of 5° C./min from 40 to 300° C. The initiation temperature of the curing peak of each composition is defined as the curing temperature, and the curing temperature is less than 110° C., ◎, 110° C. or more and less than 120° C., 120° C. or more and less than 130° C., and 130° C. or more are x. evaluated.

Epoxy resin 1: JER828 (bisphenol A type epoxy compound) Equivalent 189 Mitsubishi Chemical Co., Ltd. epoxy resin 2: Celoxide 2021P (alicyclic epoxy resin) Equivalent 136 Daicel Corp. diamine compound 1: KAYAHARD A-A (fragrance) Group diamine compound) Equivalent 63 Nippon Kayaku Co., Ltd. diamine compound 2: Wandamine HM (alicyclic diamine compound) Equivalent 53 Shin Nippon Rika Co., Ltd.
Phenol compound: HF4M (phenol novolac resin) equivalent 105 Active ester compound manufactured by Meiwa Kasei Co., Ltd.: Bisphenol A diacetate equivalent 156
Polyamine compound: diethylenetriamine equivalent 21
Curing catalyst: 2E4MZ (2-ethyl-4-methylimidazole) manufactured by Shikoku Chemicals Co., Ltd.

As is clear from the results shown in Table 1, it was confirmed that the curable resin composition containing the epoxy resin, the diamine compound, and CNF had excellent low-temperature curability and storage stability.
Although not shown in Table 1, the epoxy resin compositions described in Examples were excellent in adhesiveness, mechanical properties, chemical resistance, heat resistance, and electrical properties as cured products. Further, it also had the characteristics excellent in the low coefficient of thermal expansion peculiar to CNF.

Claims (6)

A curable resin composition containing an epoxy resin, a diamine compound, and cellulose nanofibers. The curable resin composition according to claim 1, wherein the diamine compound contains either an aromatic diamine compound or an alicyclic diamine compound. A dry film, comprising a resin layer obtained by applying or impregnating the curable resin composition according to claim 1 or 2 onto a film and drying the film. A curable resin composition according to claim 1 or 2, or the resin layer of the dry film according to claim 4, which is cured. A wiring board comprising the cured product according to claim 4. An electronic component comprising the cured product according to claim 4.