Curable resin compositions, electrical and electronic components, and methods for manufacturing electrical and electronic components.

Abstract

A curable resin composition is provided that yields a cured product with excellent adhesion to substrates, particularly difficult-to-bond resin substrates. The curable resin composition comprises (A) a curable resin, (B) an olefinically unsaturated monomer, (C) an acidic surfactant, (D) an inorganic filler, (E) a thermal polymerization initiator, and optionally a saturated polybasic acid, wherein (A) the curable resin contains at least a vinyl ester resin, the mixture of (A) the curable resin, (B) the olefinically unsaturated monomer, and the saturated polybasic acid has an acid value of 12 mg KOH / g or less, the mixture of (A) the curable resin, (B) the olefinically unsaturated monomer, (C) the acidic surfactant, and the saturated polybasic acid has an acid value of 10 mg KOH / g or more, and (C) the acidic surfactant is a low-volatility substance with an acid value of 20 mg KOH / g or more.

Description

Technical Field

[0001] This invention relates to curable resin compositions, electrical and electronic components, and methods for manufacturing electrical and electronic components. Background Technology

[0002] For electronic devices such as motors, coils, and electronic control units mounted in automobiles, a structure is required to protect the wiring board and the electronic components mounted on it, thus preventing damage from vibration or the intrusion of water and corrosive gases. In this case, a structure is generally used that seals the electronic components entirely with a material called a sealing material for fixation.

[0003] For example, Patent Document 1 discloses a sealing epoxy resin composition used in the formation of a sealing material to seal the gap between a wiring board and an electronic component. Patent Document 2 discloses an unsaturated polyester resin composition for molding electrical / electronic components containing 7-15% by weight of phenolic varnish-type vinyl ester resin, 2-5% by weight of di-unsaturated polyester resin, and 65-80% by weight of magnesium oxide.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Application Publication No. 2014-148586

[0007] Patent Document 2: Japanese Patent Application Publication No. 2004-27019 Summary of the Invention

[0008] The problem that the invention aims to solve

[0009] However, epoxy resin is relatively expensive among resins, making it difficult to use in large-scale products. Furthermore, epoxy resin compositions, due to their high molding temperature of 170–180°C and long curing time, offer potential for improvement in terms of reliability, manufacturability, and cost for electronic devices. From the viewpoint of substrate adhesion, the resin composition disclosed in Patent Document 2 has further potential for improvement.

[0010] The present invention was made to solve the aforementioned problems, and its object is to provide a curable resin composition that provides excellent adhesion to substrates, particularly difficult-to-bond resin substrates. Furthermore, an object of the present invention is to provide an electrical and electronic component having a cured material with excellent adhesion as a sealing material, and a method for manufacturing the same.

[0011] Methods for solving problems

[0012] The present invention includes the following solutions. [1]

[0014] A curable resin composition comprising:

[0015] (A) Curing resin,

[0016] (B) Unsaturated olefinic monomers,

[0017] (C) Acidic surfactants,

[0018] (D) Inorganic filler materials,

[0019] (E) Thermal polymerization initiator, and

[0020] Optional saturated polyacids,

[0021] The curable resin described above (A) contains at least a vinyl ester resin.

[0022] The acid value of the mixture of the above-mentioned (A) curable resin, the above-mentioned (B) olefinic unsaturated monomer, and the above-mentioned saturated polybasic acid is less than 12 mg KOH / g.

[0023] The acid value of the mixture of the above-mentioned (A) curable resin, (B) olefinic unsaturated monomer, (C) acidic surfactant, and saturated polybasic acid is 10 mg KOH / g or higher.

[0024] The acidic surfactant (C) mentioned above is a low-volatility substance with an acid value of 20 mg KOH / g or higher. [2]

[0026] According to the curable resin composition described in [1], the acid value of the acidic surfactant (C) is 30 to 190 mg KOH / g. [3]

[0028] According to the curable resin composition described in [1] or [2], the acidic surfactant in (C) is a phosphate ester compound. [4]

[0030] The curable resin composition according to any one of [1] to [3], wherein the above (B) olefinic unsaturated monomer is styrene. [5]

[0032] The curable resin composition according to any one of [1] to [4], wherein, relative to a total of 100 parts by weight of (A) the curable resin, (B) the olefinic unsaturated monomer, and optionally the saturated polyacid, contains

[0033] (A) 5-95 parts by weight of curing resin

[0034] (B) 5-95 parts by weight of olefinic unsaturated monomers

[0035] (C) 0.1–10 parts by weight of acidic surfactant

[0036] (D) 200-700 parts by weight of inorganic filler material, and

[0037] (E) 0.1 to 20 parts by weight of thermal polymerization initiator. [6]

[0039] The curable resin composition according to any one of [1] to [5] further comprises (F) glass fiber. [7]

[0041] The curable resin composition according to any one of [1] to [6] further comprises (G) a low-shrinkage agent. [8]

[0043] An electrical and electronic component comprising a cured product of a curable resin composition as described in any one of [1] to [7]. [9]

[0045] A method for manufacturing an electrical and electronic component includes the following steps: encapsulating the constituent components of the electrical and electronic component using a curable resin composition as described in any one of [1] to [7]; and heating and curing the aforementioned curable resin composition.

[0046] The effects of the invention

[0047] According to the present invention, a curable resin composition can be provided that yields a cured product with excellent adhesion to a substrate, particularly a difficult-to-bond resin substrate. Furthermore, a cured product with excellent adhesion obtained by curing the aforementioned curable resin composition, an electrical / electronic component comprising the cured product, and a method for manufacturing the same can be provided. Detailed Implementation

[0048] The embodiments of the present invention will now be described in detail. However, the present invention is not limited to the embodiments shown below.

[0049] In this specification, "(meth)acrylic acid" refers to methacrylic acid or acrylic acid, and "(meth)acrylate" refers to acrylate or methacrylate.

[0050] The term "olefin unsaturated bond" refers to a double bond formed between carbon atoms other than the carbon atoms that form the aromatic ring. The term "olefin unsaturated monomer" refers to a monomer that has olefin unsaturated bonds.

[0051] 1. Curable resin composition

[0052] One embodiment of the curable resin composition contains (A) a curable resin, (B) an olefinic unsaturated monomer, (C) an acidic surfactant, (D) an inorganic filler, and (E) a thermal polymerization initiator.

[0053] The curable resin composition may further contain at least one selected from saturated polybasic acid, (F) glass fiber, and (G) low shrinkage agent, as needed.

[0054] [(A) Curing Resin]

[0055] (A) The curing resin is not particularly limited to any curing resin commonly used in sealing material applications. Preferably, it is a resin having functional groups that can form a cross-linked structure when heated and cured as a curing resin composition. Specific examples of the (A) curing resin include (A-1) vinyl ester resin, (A-2) unsaturated polyester resin, (A-3) urethane (meth)acrylate resin, (A-4) diallyl phthalate resin, and (A-5) epoxy resin. From the viewpoint of material cost and moldability, the (A) curing resin preferably contains at least (A-1) vinyl ester resin. The (A) curing resin can be used alone or in combination of two or more types.

[0056] The content of (A-1) vinyl ester resin in the curable resin is preferably 75% by mass or more, more preferably 80% by mass or more, and even more preferably 90% by mass or more. If the content of (A-1) vinyl ester resin is 75% by mass or more, the material cost of the curable resin composition can be suppressed, and a cured product with better moldability and better adhesion can be obtained. There is no particular upper limit to the content of (A-1) vinyl ester resin in the curable resin. For example, it can be 100% by mass, 97% by mass, or 95% by mass.

[0057] The content of (A) curable resin is preferably 5 to 95 parts by mass relative to a total of 100 parts by mass of (A) curable resin, (B) olefinic unsaturated monomer, and optionally included saturated polyacid, more preferably 20 to 75 parts by mass, and even more preferably 30 to 50 parts by mass.

[0058] <(A-1) Vinyl Ester Resin>

[0059] (A-1) Vinyl ester resin is a compound having a free radical polymerizable unsaturated bond, generally obtained by ring-opening reaction of (a) the epoxy group of an epoxy compound having two or more epoxy groups and (b) the carboxyl group of an unsaturated monocarboxylic acid having a free radical polymerizable unsaturated bond and a carboxyl group. (A-1) Vinyl ester resin is described, for example, in the Polyester Resin Handbook (Nikkan Kogyo Shimbun, 1988).

[0060] (A-1) vinyl ester resins can be used alone or in combination with two or more. From an operational perspective, (A-1) vinyl ester resins are generally diluted with (B) olefinically unsaturated monomers before use. By using (A-1) vinyl ester resins, the material cost of the curable resin composition can be reduced, and cured products with excellent adhesion can be obtained.

[0061] (A-1) The number-average molecular weight (Mn) of the vinyl ester resin can be adjusted according to desired physical properties, but from an operational perspective, a range of 500 to 5,000 is preferred. In this specification, "weight-average molecular weight" and "number-average molecular weight" are values ​​obtained by gel permeation chromatography (GPC) at room temperature (23°C) under the following conditions using a standard polystyrene standard curve.

[0062] Device: Shodex (registered trademark) GPC-101 (Showa Denko Co., Ltd.)

[0063] Pillar: Shodex (registered trademark) LF-804 (Showa Denko Co., Ltd.)

[0064] Column temperature: 40℃

[0065] Sample: 0.2% by mass tetrahydrofuran solution of the sample

[0066] Flow rate: 1 mL / min

[0067] Eluent: Tetrahydrofuran

[0068] Detector: Shodex (registered trademark) RI-71S (Showa Denko Co., Ltd.)

[0069] (a) Epoxy compounds)

[0070] (a) The epoxy compound is not particularly limited as long as it has two or more epoxy groups. Preferably, it is selected from at least one of bisphenol type epoxy compounds and phenolic varnish type epoxy compounds, more preferably bisphenol type epoxy compounds. By using (a) epoxy compound as a raw material in (A-1) vinyl ester resin, the mechanical strength and corrosion resistance of the cured product are further improved.

[0071] Examples of bisphenol-type epoxy compounds include substances obtained by reacting bisphenol compounds such as bisphenol A, bisphenol F, bisphenol S, and tetrabromobisphenol A with epichlorohydrin and / or methylepimerol; and substances obtained by reacting a compound that has undergone glycidyl etherification of one or more of the above-mentioned bisphenol compounds with a condensate of one or more of the above-mentioned bisphenol compounds, and then with epichlorohydrin and / or methylepimerol. From the viewpoint of durability, the reaction product of bisphenol compound and epichlorohydrin is preferred, and the reaction product of bisphenol A and epichlorohydrin is more preferred.

[0072] Examples of phenolic varnishes that are phenolic epoxy compounds include, for instance, substances obtained by reacting phenolic varnishes or cresol varnishes with epichlorohydrin and / or methyl epichlorohydrin.

[0073] (b) Unsaturated monocarboxylic acids)

[0074] (b) There are no particular restrictions on the unsaturated monocarboxylic acid as long as it is a monocarboxylic acid with an olefinic unsaturated bond. Preferred are methacrylic acid, acrylic acid, crotonic acid, cinnamic acid, etc., more preferably acrylic acid or methacrylic acid, and from the viewpoint of corrosion resistance of the cured product, methacrylic acid is even more preferred.

[0075] ((A-1) Synthesis method of vinyl ester resin)

[0076] (A-1) Vinyl ester resins can be synthesized by known synthetic methods. For example, a method in which an esterification catalyst and (a) an epoxy compound are added to an unsaturated monocarboxylic acid in a heated and stirred reaction vessel, and the reaction is carried out at 70–150°C, preferably 80–140°C, and more preferably 90–130°C.

[0077] In addition, the unreacted (b) unsaturated monocarboxylic acid after the synthesis of (A-1) vinyl ester resin is regarded as the (B) olefinic unsaturated monomer described later.

[0078] As esterification catalysts, known catalysts such as triethylamine, N,N-dimethylbenzylamine, N,N-dimethylaniline, tertiary amines such as diazabicyclooctane, triphenylphosphine, and diethylamine hydrochloride can be used.

[0079] The mixing ratio of (a) the epoxy compound and (b) the unsaturated monocarboxylic acid is preferably such that, relative to the total amount of epoxy groups in (a) the epoxy compound is 1 mole, and the total amount of carboxyl groups in (b) the unsaturated monocarboxylic acid is 0.3 to 1.2 moles, more preferably 0.4 to 1.1 moles, and even more preferably 0.5 to 1.0 moles. If the total amount of carboxyl groups in (b) the unsaturated monocarboxylic acid is 0.3 moles or more, a cured product with sufficient hardness can be obtained when the curable resin composition is cured. On the other hand, if the total amount of carboxyl groups in (b) the unsaturated monocarboxylic acid is 1.2 moles or less, unreacted (b) unsaturated monocarboxylic acid can be reduced when synthesizing (A-1) vinyl ester resin, thus reducing the acid value of the mixture of components (A) and (B), and a cured product with better adhesion can be obtained.

[0080] The unreacted (b)-unsaturated monocarboxylic acid remaining after the synthesis of the (A-1) vinyl ester resin can be used directly as the (B) olefinic unsaturated monomer of the curable resin composition without being removed. During heat curing of the curable resin composition, the unreacted (b)-unsaturated monocarboxylic acid may volatilize or leach out, affecting the adhesion of the cured product. Therefore, it is preferable to minimize the content of the unreacted (b)-unsaturated monocarboxylic acid. For example, the content of the unreacted (b)-unsaturated monocarboxylic acid is preferably 5% by mass or less, more preferably 3% by mass or less, relative to the total amount of (A-1) vinyl ester resin and unreacted (b)-unsaturated monocarboxylic acid.

[0081] <(A-2) Unsaturated Polyester Resin>

[0082] (A-2) Unsaturated polyester resin is a condensation polymer of polyol and unsaturated polyacid, or a condensation polymer of polyol, unsaturated polyacid and saturated polyacid, without particular limitation.

[0083] (A-2) unsaturated polyester resin can be used alone or in combination with two or more other resins. By using (A-2) unsaturated polyester resin, cured products with excellent mechanical strength and heat resistance can be obtained.

[0084] Furthermore, in this disclosure, styrene monomers and the like contained in general unsaturated polyester resins are classified as (B) olefinic unsaturated monomers.

[0085] There are no particular limitations on polyols as long as they are compounds having two or more hydroxyl groups. Examples of polyols include ethylene glycol, propylene glycol, butanediol, diethylene glycol, dipropylene glycol, triethylene glycol, pentanediol, hexanediol, neopentanediol, tetraethylene glycol, polyethylene glycol, 2-methyl-1,3-propanediol, 1,4-cyclohexanediol, hydrogenated bisphenol A, and other alkylene glycols; bisphenol A; ethylene oxide adducts of bisphenol A, propylene oxide adducts of bisphenol A, and other olefinically modified bisphenol A; glycerol, etc. From the viewpoint of heat resistance, mechanical strength, and flowability of the cured resin composition during molding, propylene glycol, dipropylene glycol, neopentanediol, hydrogenated bisphenol A, and bisphenol A are preferred, and propylene glycol is more preferred. Polyols can be used alone or in combination of two or more.

[0086] Unsaturated polybasic acids are not particularly limited as long as they have olefinic unsaturated bonds and two or more carboxyl groups, and can be well-known substances. In particular, unsaturated polybasic acids or their anhydrides with 4 to 6 carbon atoms are preferred because they are lower in cost and can produce curable resin compositions with superior mechanical strength and heat resistance of the cured product. Examples of unsaturated polybasic acids include, for example, maleic acid, maleic anhydride, fumaric acid, citracic acid, itaconic acid, and chloromaleic acid. More preferably, unsaturated polybasic acids selected from fumaric acid, maleic acid, maleic anhydride, and itaconic acid are preferred. Unsaturated polybasic acids can be used alone or in combination of two or more.

[0087] Preferred combinations of polyols and unsaturated polyacids include, for example, combinations of fumaric acid and neopentyl glycol, maleic acid and dipropylene glycol, maleic anhydride and propylene glycol, fumaric acid and propylene glycol, and fumaric acid, hydrogenated bisphenol A, and propylene glycol. Combinations of fumaric acid and propylene glycol, and fumaric acid, hydrogenated bisphenol A, and propylene glycol are preferred because they offer lower costs and provide curable resin compositions with higher heat distortion temperatures, superior mechanical strength, and better heat resistance.

[0088] There are no particular limitations on saturated polybasic acids; any compound or its anhydride that does not have an olefinic unsaturated bond and has two or more carboxyl groups can be used, and known substances can be employed. Examples of saturated polybasic acids include, for instance, aromatic saturated polybasic acids or their anhydrides such as phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, nitrophthalic acid, and halophthalic anhydride; aliphatic saturated polybasic acids such as succinic acid, adipic acid, sebacic acid, oxalic acid, malonic acid, azelaic acid, and glutaric acid; and hexahydrophthalic anhydride. Saturated polybasic acids can be used alone or in combination of two or more.

[0089] (A-2) The weight-average molecular weight (Mw) of the unsaturated polyester resin is not particularly limited. The weight-average molecular weight of the unsaturated polyester resin is preferably 2,000 to 25,000, more preferably 3,000 to 20,000, and even more preferably 3,500 to 10,000. As long as the weight-average molecular weight is 2,000 to 25,000, the moldability of the curable resin composition becomes better.

[0090] The degree of unsaturation of the (A-2) unsaturated polyester resin is preferably 50 to 100 mol%, more preferably 60 to 100 mol%, and even more preferably 70 to 100 mol%. If the degree of unsaturation is within the above range, the moldability of the curable resin composition containing the (A-2) unsaturated polyester resin becomes better.

[0091] (A-2) The degree of unsaturation of unsaturated polyester resin can be calculated using the number of moles of unsaturated polybasic acid and saturated polybasic acid used as raw materials, by the following formula.

[0092] Degree of unsaturation (mol%) = {(number of moles of unsaturated polyacid × number of olefinic unsaturated bonds per molecule of unsaturated polyacid) / (number of moles of unsaturated polyacid + number of moles of saturated polyacid)} × 100

[0093] ((A-2) Synthesis method of unsaturated polyester resin)

[0094] (A-2) Unsaturated polyester resins can be synthesized using the above-mentioned raw materials by known methods. (A-2) The various conditions in the synthesis of unsaturated polyester resins are appropriately set according to the raw materials used and their quantities.

[0095] Generally, esterification reactions can be carried out under pressure or reduced pressure in a stream of inert gases such as nitrogen at temperatures ranging from 140°C to 230°C. An esterification catalyst can be used as needed for the reaction. Examples of known esterification catalysts include manganese acetate, dibutyltin oxide, stannous oxalate, zinc acetate, and cobalt acetate. Esterification catalysts can be used alone or in combination of two or more.

[0096] In addition, the unreacted unsaturated polyacids after the synthesis of (A-2) unsaturated polyester resin are considered as (B) olefinic unsaturated monomers as described later.

[0097] Because of the increased molecular weight due to the increased reaction rate and the improved binding due to the decreased acid value, the equivalent amount of hydroxyl groups in the polyol is preferably in the range of 0.9 to 1.2 relative to the total amount of carboxyl groups in the unsaturated polyacid and optionally the saturated polyacid.

[0098] Unreacted unsaturated polybasic acids and optional saturated polybasic acids from the synthesis of (A-2) unsaturated polyester resin may be present in the curable resin composition without being removed.

[0099] <(A-3) urethane (meth)acrylate resin>

[0100] As a (A-3) urethane (meth)acrylate resin, a resin obtained by, for example, introducing (meth)acryloyl groups into the two-terminal hydroxyl or isocyanate groups of a polyurethane obtained by reacting a polyisocyanate with a polyol.

[0101] As a polyol, the compound described as a raw material for the above-mentioned (A-2) unsaturated polyester resin can be used without particular restriction.

[0102] Examples of polyisocyanates include, for instance, aliphatic polyisocyanates such as 1,6-hexamethylene diisocyanate, lysine diisocyanate, lysine triisocyanate, and trimethylhexane diisocyanate; cyclic aliphatic polyisocyanates such as hydrogenated phenylene diisocyanate, isophorone diisocyanate, methylcyclohexane-2,4 (or 2,6)-diisocyanate, 4,4'-methylene bis(cyclohexyl)isocyanate, and 1,3-(isocyanatomethyl)cyclohexane; aromatic polyisocyanates such as toluene diisocyanate, phenylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, and triphenylmethane triisocyanate; and adducts, isocyanurates, and biuretates of these polyisocyanates. Polyisocyanates can be used alone or in combination of two or more.

[0103] When introducing a (meth)acryloyl group, for example, a method can be used to react a (meth)acrylic compound containing a hydroxyl group with a terminal isocyanate group, or a method can be used to react a (meth)acrylic compound containing an isocyanate group, such as 2-(meth)acryloyloxyethyl isocyanate, 2-(meth)acryloyloxypropyl isocyanate, 1,1-bis(acryloyloxymethyl)ethyl isocyanate, with a terminal hydroxyl group. Examples of hydroxyl-containing (meth)acrylic compounds include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, caprolactone-modified hydroxyalkyl (meth)acrylate, polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, tri(hydroxyethyl)isocyanurate di(meth)acrylate, pentaerythritol tri(meth)acrylate, glycerol mono(meth)acrylate, and hydroxyethyl acrylamide, with 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, caprolactone-modified hydroxyalkyl (meth)acrylate, and hydroxyethyl acrylamide being preferred. (Meth)acrylic compounds containing isocyanate groups and (meth)acrylic compounds containing hydroxyl groups can be used alone or in combination of two or more.

[0104] In addition, unreacted hydroxyl-containing (meth)acrylate compounds or unreacted isocyanate-containing (meth)acrylate compounds after the synthesis of (A-3) urethane (meth)acrylate resin are considered as (B) olefinic unsaturated monomers as described later.

[0105] <(A-4) diallyl phthalate resin>

[0106] (A-4) Diallyl phthalate resin is an oligomer obtained by the esterification reaction of diallyl phthalate and polyol, and conventionally known substances can be used without particular restriction. (A-4) Diallyl phthalate resin can be used alone or in combination with two or more types.

[0107] In addition, unreacted diallyl phthalate after the synthesis of (A-4) diallyl phthalate resin may not be removed and may remain in the curable resin composition.

[0108] <(A-5) Epoxy Resin>

[0109] As (A-5) epoxy resin, the compounds described in (a) Epoxy Compounds may be used. (A-5) Epoxy resin may be used alone or in combination of two or more.

[0110] [(B) olefinic unsaturated monomers]

[0111] (B) There are no particular restrictions on the presence of olefinic unsaturated monomers, as long as they do not conform to the acidic surfactants described later in (C). (B) Olefinic unsaturated monomers can be used alone or in combination of two or more. From the viewpoint of reducing the acid value of the mixture of components (A), (B), and optionally included saturated polyacids, compounds without carboxyl groups are preferred.

[0112] Specifically, examples include vinyl compounds such as styrene, vinyltoluene, tert-butylstyrene, methoxystyrene, divinylbenzene, vinylnaphthalene, and acenaphthene; methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, tert-butyl methacrylate, 2-ethylhexyl methacrylate, isodecanyl methacrylate, lauryl methacrylate, tridecyl methacrylate, stearyl methacrylate, cyclohexyl methacrylate, furfuryl methacrylate, and tetrahydrofurfuryl methacrylate. Esters, phenyl methacrylate, benzyl methacrylate, phenoxyethyl methacrylate, dicyclopentenyl methacrylate, dicyclopentenyloxyethyl methacrylate, allyl methacrylate, isobornyl methacrylate, acetoacetoxyethyl methacrylate, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, propylene glycol dimethacrylate, neopentyl glycol dimethacrylate, tricyclodecyl dimethacrylate, trimethylolpropane trimethacrylate, etc. (meth)acrylates. From the viewpoint of copolymerization with component (A), vinyl compounds are preferred, more preferably one or more selected from styrene, vinyltoluene, tert-butylstyrene, and methoxystyrene, and even more preferably styrene.

[0113] The content of (B) the olefinic unsaturated monomer, relative to a total of 100 parts by mass of (A) the curable resin, (B) the olefinic unsaturated monomer, and optionally the saturated polybasic acid, is preferably 5 to 95 parts by mass, more preferably 25 to 80 parts by mass, and even more preferably 50 to 70 parts by mass. If the content of (B) the olefinic unsaturated monomer is 5 parts by mass or more, the viscosity of the curable resin composition can be adjusted to an appropriate range, resulting in good moldability. If the content of (B) the olefinic unsaturated monomer is 95 parts by mass or less, the cured product exhibits good mechanical strength.

[0114] The mixture comprising (A) the curable resin, (B) the olefinic unsaturated monomer, and optionally a saturated polybasic acid has an acid value of 12 mg KOH / g or less, preferably 11 mg KOH / g or less, and more preferably 10.5 mg KOH / g or less. There is no particular limitation on the lower limit of the acid value of this mixture; for example, it can be 1 mg KOH / g or more, 3 mg KOH / g or more, or 5 mg KOH / g or more. The saturated polybasic acid can be an unreacted saturated polybasic acid from the synthesis of (A) the curable resin. If the acid value of this mixture is 12 mg KOH / g or less, the cured product exhibits good adhesion.

[0115] If the mixture contains a high amount of unreacted monomers from the synthesis of (A) curable resin, such as unreacted (b) unsaturated monocarboxylic acids from the synthesis of (A-1) vinyl ester resin, or unreacted unsaturated polycarboxylic acids and saturated polycarboxylic acids from the synthesis of (A-2) unsaturated polyester resin, the acid value of the mixture will increase due to these unreacted monomers. It can be assumed that when a curable resin composition containing such a mixture is heated for curing, the unreacted monomers volatilize or leach out, affecting the adhesion. Therefore, the acid value of the mixture can be used as an indicator of the adhesion of the cured resin composition.

[0116] In addition, the acid value in this disclosure is a value determined according to JIS K0070:1992, and is determined by the following steps.

[0117] Accurately weigh approximately 2 g of the sample into a 100 mL conical flask using a precision balance, and dissolve it in 10 mL of a 1 / 1 (by weight) mixture of ethanol and diethyl ether. Further, add 1–3 drops of phenolphthalein ethanol solution as an indicator to the flask and stir thoroughly until the sample becomes homogeneous. Titrate the sample with 0.1 M potassium hydroxide ethanol solution, and define the neutralization endpoint as the period when the indicator remains a pale red color for 30 seconds. The acid value of the mixture is calculated using the following formula (1).

[0118] Acid value (mgKOH / g)=[B×f×5.661] / S……(1)

[0119] In addition, the calculation of B, f, and S in formula (1) is as follows.

[0120] B: Volume (mL) of 0.1M potassium hydroxide ethanol solution used

[0121] f: Factor for 0.1M potassium hydroxide ethanol solution (correction for batch-to-batch fluctuations in reagents)

[0122] S: Sample volume (g)

[0123] [(C) Acidic surfactants]

[0124] (C) Acidic surfactants are low-volatility substances with surface activity and an acid value of 20 mg KOH / g or higher. There are no particular limitations as long as they exhibit excellent compatibility with (A) curable resins and (B) olefinic unsaturated monomers, (D) inorganic fillers (described later), and (F) glass fibers (optional component). Compounds that meet both the criteria of saturated polybasic acid and (C) acidic surfactant are classified as (C) acidic surfactants.

[0125] In this disclosure, a low-volatility substance is defined as a substance that retains 90% or more of its weight under atmospheric conditions at 150°C for 60 minutes. The molecular weight or weight-average molecular weight of a low-volatility substance is, for example, 500 or more, 1,000 or more, or 1,500 or more. There is no particular upper limit to the molecular weight or weight-average molecular weight of a low-volatility substance; for example, it can be 7,000 or less, 6,000 or less, or 5,000 or less.

[0126] As (C) the acidic surfactant, substances generally known as dispersants or plasticizers in resin compositions can be used. Low-volatility oligomers are preferred, more preferably low-volatility oligomers having constituent components including monomer units such as ethylene units, styrene units, ester units, ether units, and urethane units, and acid groups such as carboxyl groups, sulfonyl groups, and phosphogroups. Phosphate ester compounds or carboxylic acid ester compounds are further preferred, and phosphate ester compounds comprising long-chain polyester structures are even more preferred.

[0127] To improve the adhesion of the cured product, it is effective to enhance the wettability of the cured resin composition to the substrate (adhesive). Therefore, it is considered important that the cured resin composition has an acid value of a certain value or higher. The adhesion of the cured product is improved by using an acidic surfactant (C) with an acid value of 20 mg KOH / g or higher. Furthermore, when the cured resin composition is heated for curing, a low-volatility substance can be used as the acidic surfactant (C) to prevent the volatilization or exudation of the acidic surfactant from affecting the adhesion of the cured product.

[0128] As the aforementioned phosphate ester compounds, substances described in Japanese Patent Application Publication No. 61-194091, Japanese Patent Application Publication No. 3-112992, Japanese Patent Publication No. 2007-527896, and Japanese Patent Publication No. 2014-520127 are suitable. Specifically, examples include phosphate triester compounds of methyl esters of 12-hydroxystearic acid polyester, ester compounds of polyethylene glycol monomethyl ether and malic acid, and ester compounds of tetraphosphate.

[0129] As (C) the acidic surfactant, commercially available products can also be used, such as those manufactured by BYK Additives & Instruments: BYK W-9010, BYK W-9011, BYK P-9051, BYK P-9050, BYK P-9060, BYK P-9065, BYK P-9080, BYK P-9085, etc. From the viewpoint of the adhesion of the cured product, BYK W-9010 and BYK P-9051 are preferred.

[0130] (C) The acid value of the acidic surfactant is 20 mg KOH / g or higher, preferably 30–190 mg KOH / g, more preferably 100–180 mg KOH / g, and even more preferably 120–160 mg KOH / g. If the acid value is less than 20 mg KOH / g, a large amount of (C) acidic surfactant needs to be mixed in order to ensure the acid value of the curable resin composition, which can easily have an adverse effect on the properties of the cured product, such as adhesion.

[0131] The content of (C) acidic surfactant relative to 100 parts by mass of the total of (A) curable resin, (B) olefinic unsaturated monomer, and optionally included saturated polybasic acid is preferably 0.1 to 10 parts by mass, more preferably 0.5 to 9 parts by mass, and even more preferably 1 to 8 parts by mass. If the content of (C) acidic surfactant is 0.1 parts by mass or more, the curable resin composition has a sufficient acid value, and a cured product with good adhesion can be obtained. If the content of (C) acidic surfactant is 10 parts by mass or less, it will not adversely affect the properties of the cured product.

[0132] The mixture comprising (A) a curable resin, (B) an olefinically unsaturated monomer, (C) an acidic surfactant, and optionally a saturated polybasic acid has an acid value of 10 mg KOH / g or higher, preferably 10 to 30 mg KOH / g, and more preferably 11 to 20 mg KOH / g. If the acid value of this mixture is 10 mg KOH / g or higher, the wettability of the curable resin composition to the adherend is improved, and a cured product with sufficient adhesion can be obtained.

[0133] [(D) Inorganic filler materials]

[0134] As the (D) inorganic filler material, particulate substances known in the technical field of this invention can be used. By using the (D) inorganic filler material, the molding shrinkage of the molded article can be reduced, the workability can be improved by adjusting the viscosity of the curable resin composition, or the strength of the molded article can be increased.

[0135] Examples of inorganic fillers (D) include calcium carbonate, silicon dioxide, aluminum oxide, aluminum hydroxide, barium sulfate, calcium sulfate, calcium hydroxide, calcium oxide, magnesium oxide, magnesium hydroxide, wollastonite, clay, kaolin, mica, gypsum, silicic anhydride, and glass powder. Calcium carbonate, aluminum oxide, and aluminum hydroxide are preferred due to their low cost. Inorganic fillers (D) can be used alone or in combination of two or more.

[0136] (D) The average particle size of the inorganic filler is preferably 1 to 100 μm, more preferably 1 to 60 μm, and even more preferably 1 to 50 μm. If the average particle size of the inorganic filler (D) is 1 μm or more, particle aggregation can be suppressed. On the other hand, if the average particle size of the inorganic filler (D) is 100 μm or less, the curable resin composition has good formability.

[0137] In addition, the term "average particle size" in this specification refers to the 50% particle size (D50) in the volume-based cumulative particle size distribution measured by a laser diffraction / scattering particle size distribution measuring device (Microtron Vel Co., Ltd., FRA).

[0138] (D) There are no particular restrictions on the shape of inorganic filler materials. Examples include approximately spheres, ellipsoids, scaly shapes, and amorphous shapes.

[0139] The amount of inorganic filler (D) is preferably 200 to 700 parts by mass, more preferably 300 to 600 parts by mass, relative to a total of 100 parts by mass of the curable resin (A), the olefinic unsaturated monomer (B), and the optionally included saturated polybasic acid. If the amount of inorganic filler (D) is 200 parts by mass or more, the mechanical properties of the cured product are better. If the amount of inorganic filler (D) is 700 parts by mass or less, the inorganic filler (D) is more uniformly dispersed in the curable resin composition, and a homogeneous molded article can be produced.

[0140] [(E) Thermal polymerization initiator]

[0141] As a (E) thermal polymerization initiator, there is no particular limitation as long as it is a polymerization initiator that generates free radicals through heating. Examples include peroxides such as acyl peroxide, ester peroxide, hydroperoxide, dialkyl peroxide, ketone peroxide, peroxyketal, alkyl perester, and percarbonate.

[0142] As the (E) thermal polymerization initiator, among these peroxides, 1,1-di-tert-hexylperoxide-cyclohexane, tert-hexylperoxide isopropyl monocarbonate, tert-butylperoxide octanoate, tert-butylperoxide-2-ethylhexanoate, tert-hexylperoxide-2-ethylhexanoate, tert-pentylperoxide-2-ethylhexanoate, benzoyl peroxide, 1,1-di-tert-butylperoxide-3,3,5-trimethylcyclohexane, tert-butylperoxide isopropyl carbonate, tert-butylperoxide benzoate, dicumyl peroxide, and di-tert-butylperoxide are preferred. The (E) thermal polymerization initiator can be used alone or in combination of two or more.

[0143] The amount of (E) thermal polymerization initiator mixed with the curing resin is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 5 parts by mass, relative to a total of 100 parts by mass of (A) curable resin, (B) olefinic unsaturated monomer, and optionally included saturated polybasic acid. If the amount of (E) thermal polymerization initiator mixed with the curing resin is 0.1 parts by mass or more, the curing reaction during molding of the curable resin composition proceeds uniformly, and the physical properties and appearance of the cured product become better. If the amount of (E) thermal polymerization initiator mixed with the curing resin is 20 parts by mass or less, the storage stability of the curable resin composition becomes better, and the workability is improved.

[0144] [(F) Glass fiber]

[0145] The curable resin composition may contain (F) glass fibers as needed. There are no particular limitations on the (F) glass fibers, as long as they are fibrous materials with an aspect ratio of 3 or greater. Specifically, chopped strand glass fibers can be cited as an example.

[0146] (F) The fiber length of the glass fiber is preferably 20 mm or less, more preferably 10 mm or less, and even more preferably 5 mm or less. If the fiber length is 20 mm or less, the curable resin composition has good formability and the cured product has a good appearance. The fiber length is preferably 0.1 mm or more, more preferably 0.5 mm or more, and even more preferably 1 mm or more. If the fiber length is 0.1 mm or more, the cured product has good strength. (F) The average fiber diameter of the glass fiber is preferably 3 to 100 μm, more preferably 5 to 30 μm.

[0147] When using glass fiber (F), its content relative to a total of 100 parts by mass of (A) curable resin, (B) olefinic unsaturated monomer, and optionally included saturated polybasic acid is preferably 1 to 300 parts by mass, more preferably 5 to 100 parts by mass, and even more preferably 10 to 50 parts by mass. If the content of glass fiber (F) is 1 part by mass or more, the mechanical properties of the molded article obtained by the curable resin composition are better. If the content of glass fiber (F) is 300 parts by mass or less, the glass fiber (F) is more uniformly dispersed in the curable resin composition, and a homogeneous molded article can be produced.

[0148] [(G) Low shrinkage agent]

[0149] The curable resin composition may contain a (G) low-shrinkage agent as needed. There are no particular limitations on the (G) low-shrinkage agent; any substance known in the art of this invention may be used. A thermoplastic resin is preferred as the (G) low-shrinkage agent. Examples of (G) low-shrinkage agents include, for example, polystyrene, polyethylene, polymethyl methacrylate, polyvinyl acetate, saturated polyester, polycaprolactone, styrene-butadiene rubber, etc. The (G) low-shrinkage agent may be used alone or in combination of two or more.

[0150] The content of the low-shrinkage agent (G) is preferably 10 to 80 parts by mass, more preferably 15 to 30 parts by mass, relative to a total of 100 parts by mass of the curable resin (A), the olefinic unsaturated monomer (B), and optionally the saturated polybasic acid. If the content of the low-shrinkage agent (G) is 10 parts by mass or more, the shrinkage rate of the cured product is reduced, and the desired dimensional accuracy can be obtained in the molded article. If the content of the low-shrinkage agent (G) is 80 parts by mass or less, the mechanical properties of the cured product are better.

[0151] [Other additives]

[0152] In addition to the above-mentioned components, the curable resin composition may also include, within a range that does not impair the effects of the invention, thickeners, colorants, polymerization inhibitors, viscosity modifiers such as anti-tack agents, molding aids such as release agents, and other components known in the technical field of the present invention.

[0153] Thickeners are compounds other than (D) inorganic fillers that exhibit a thickening effect; examples include isocyanate compounds. Thickeners can be used alone or in combination of two or more. The amount of thickener added can be adjusted appropriately according to the required workability, flowability, etc., of the curable resin composition.

[0154] Colorants are used to color cured materials. Various dyes, inorganic pigments, or organic pigments can be used as colorants. Colorants can be used alone or in combination of two or more. The amount of colorant added can be adjusted appropriately according to the desired degree of coloring of the cured material.

[0155] Examples of polymerization inhibitors include hydroquinone, trimethylhydroquinone, p-benzoquinone, naphthoquinone, tert-butylhydroquinone, catechol, p-tert-butylcatechol, and 2,6-di-tert-butyl-4-methylphenol. Inhibitors can be used alone or in combination of two or more. The amount of inhibitor added can be adjusted appropriately based on the storage environment and duration of the curable resin composition, curing conditions, etc.

[0156] 2. Method for manufacturing curable resin compositions

[0157] The curable resin composition can be manufactured by mixing (A) a curable resin, (B) an olefinic unsaturated monomer, (C) an acidic surfactant, (D) an inorganic filler, (E) a thermal polymerization initiator, (F) glass fiber, (G) a low-shrinkage agent, other additives except (C) the acidic surfactant, or a combination of two or more of these components. A saturated polybasic acid may be included in the curable resin composition, which may be derived from the saturated polybasic acid used in the manufacture of (A) the curable resin.

[0158] Examples of mixing methods include, for instance, kneading. There are no particular limitations on the kneading method; examples include kneading using a kneader, disperser, planetary mixer, etc. The kneading temperature is preferably 5°C to 50°C, more preferably 10°C to 40°C.

[0159] There are no particular restrictions on the order in which the components are mixed when manufacturing the curable resin composition. For example, it is preferable to mix the curable resin (A) with a portion or all of the olefinic unsaturated monomer (B) before mixing the other components, as this readily yields a curable resin composition in which the components are well dispersed or uniformly mixed. At least a portion of the olefinic unsaturated monomer (B) may be premixed with the curable resin (A) as if it were a solvent, dispersion medium, or the like.

[0160] As a mixing method when using (F) glass fibers, one example is to prepare glass fibers with a predetermined fiber length distribution in advance and mix the (F) glass fibers into a composition containing all components except the (F) glass fibers. According to this method, the fiber length distribution of the (F) glass fibers can be finely adjusted. Furthermore, another example is to achieve a predetermined fiber length distribution by breaking the (F) glass fibers through mixing after preparing a curable resin composition containing (F) glass fibers. The fiber length distribution of the (F) glass fibers can be controlled by conditions such as the type and amount of other components being mixed, the type of mixer, the mixing speed, the mixing temperature, and the mixing time. This method is simple because it does not require pre-breaking the (F) glass fibers.

[0161] 3. Methods for manufacturing cured products

[0162] The curable resin composition can be cured by heating as needed. The curing conditions for the curable resin composition can be appropriately set according to the materials used. As an example of preferred conditions, the temperature is 120 to 180°C, more preferably 120 to 160°C, and the curing time is 1 to 30 minutes.

[0163] 4. Manufacturing method of molded body

[0164] By molding the curable resin composition into a desired shape and then curing it, a molded article containing a cured resin composition can be manufactured. There are no particular limitations on the molding and curing methods; methods commonly practiced in the technical field of this invention, such as compression molding, transfer molding, and injection molding, can be used.

[0165] For example, there are methods such as opening a mold, injecting a curable resin composition into the mold, and allowing it to cure; or injecting a curable resin composition into a closed mold through an injection port or similar opening under reduced pressure, or in the case of injection molding, under pressure applied from the outside of the mold, and allowing it to cure. The conditions for curing the resin composition in the mold can be appropriately set depending on the material used. As an example of preferred conditions, a temperature of 120–180°C, more preferably 120–160°C, and a curing time of 1–30 minutes are also preferred.

[0166] In one embodiment, an electrical-electronic component comprising a cured product of a curable resin composition is provided. The electrical-electronic component can be manufactured, for example, by encapsulating constituent parts of the electrical-electronic component using a curable resin composition and then heating and curing the curable resin composition. Encapsulation of the constituent parts of the electrical-electronic component can be performed, for example, by injecting the curable resin composition into a housing containing the constituent parts.

[0167] From an adhesion perspective, curable resin compositions are suitable for use on polyphenylene sulfide (PPS) substrates, polybutylene terephthalate (PBT) substrates, epoxy glass substrates, and copper substrates. In particular, curable resin compositions can achieve excellent adhesion to difficult-to-bond resin substrates such as PPS substrates. By using curable resin compositions, surface treatment processes such as primer application and plasma treatment, typically performed on difficult-to-bond resin substrates such as PPS substrates, can be omitted.

[0168] Example

[0169] The present invention will be further described in detail below through examples and comparative examples, but the present invention is not limited to the following examples.

[0170] The following shows an example of the synthesis of (A) curable resin.

[0171] [Synthetic Example 1] (A-1) Synthesis of Vinyl Ester Resin

[0172] In a 1L four-necked flask equipped with a thermometer, stirrer, gas inlet, and reflux cooler, 478.9g of bisphenol A type epoxy resin AER-2603 (Asahi Kasei Epoxy Materials Co., Ltd.) with an epoxy equivalent of 188.0 and 73.1g of methacrylic acid with 0.35g of methylhydroquinone dissolved were added, and the mixture was stirred and heated. When the temperature reached 100-110°C, 146.2g of methacrylic acid with 1.4g of 2,4,6-tris(dimethylaminomethyl)phenol (Sekol (registered trademark) TDMP, Seiko Chemical Co., Ltd.) dissolved was added dropwise over 30 minutes, and the mixture was allowed to react at 130°C. The resin was cooled when the acid value dropped below 30 mg KOH / g, and 389 g of styrene and 0.1 g of hydroquinone were added to synthesize a bisphenol A type vinyl ester resin containing 47% by mass of styrene.

[0173] [Synthesis Example 2] (A-2) Synthesis of Unsaturated Polyester Resin

[0174] In a four-necked flask equipped with a thermometer, stirrer, inert gas inlet, and reflux cooler, 0.93 kg (9.5 mol) of maleic anhydride, 0.07 kg (0.5 mol) of phthalic anhydride, and 0.76 kg (10 mol) of propylene glycol were added. An esterification reaction was carried out under a nitrogen atmosphere with stirring until the temperature reached 200 °C, yielding an unsaturated polyester resin. Then, styrene monomer was added at a concentration of 30% by mass relative to the total amount of the unsaturated polyester resin and styrene monomer, resulting in a mixture of unsaturated polyester resin and styrene. The resulting unsaturated polyester resin had an unsaturation degree of 95 mol% and a weight-average molecular weight of 8,000.

[0175] "Weight-average molecular weight" and "number-average molecular weight" are values ​​obtained by gel permeation chromatography (GPC) at room temperature (23°C) under the following conditions, using a standard polystyrene standard curve.

[0176] Device: Shodex (registered trademark) GPC-101 (Showa Denko Co., Ltd.)

[0177] Pillar: Shodex (registered trademark) LF-804 (Showa Denko Co., Ltd.)

[0178] Column temperature: 40℃

[0179] Sample: 0.2% by mass tetrahydrofuran solution of the sample

[0180] Flow rate: 1 mL / min

[0181] Eluent: Tetrahydrofuran

[0182] Detector: Shodex (registered trademark) RI-71S (Showa Denko Co., Ltd.)

[0183] The following substances were used as other ingredients.

[0184] (B) Unsaturated olefinic monomers:

[0185] Styrene (Idemitsu Kosan Co., Ltd.)

[0186] (C) Acidic surfactants:

[0187] • BYK W-9010 (Phosphate ester dispersant, acid value 129 mg KOH / g, weight retention rate of over 99% at 150℃ for 60 minutes, BYK Corporation)

[0188] BYK P-9051 (Polyester-based dispersant, acid value 157 mg KOH / g, weight retention rate of over 99% at 150℃ for 60 minutes, BYK Corporation)

[0189] (D) Inorganic filler materials:

[0190] · Softon 1200 (Calcium carbonate, average particle size 1.80 μm, Bihoku Powdered Chemical Industry Co., Ltd.)

[0191] (E) Thermal polymerization initiator:

[0192] ·Luperox 575 (tert-amyl peroxide-2-ethylhexanoate, Alkema Yoshitomi Co., Ltd.)

[0193] (F) Glass fiber:

[0194] • ECS-03B173 / P9 (fiber diameter 13μm, fiber length 3mm, Nippon Electric Glass Co., Ltd.)

[0195] (G) Low shrinkage agent:

[0196] ·Taketoron (Polyethylene powder, Takehara Chemical Industry Co., Ltd.)

[0197] Other additives besides (C) acidic surfactants (C'):

[0198] Stearic acid (acid value 197 mg KOH / g, 150℃, 89% weight retention after 60 minutes, Nippon Oil Co., Ltd.)

[0199] Lucant HC-100 (co-oligomer of ethylene and α-olefin, acid-free, Mitsui Chemicals Co., Ltd.)

[0200] ·Dipropylene glycol (no acid value, boiling point 232°C, Dosage Co., Ltd.)

[0201] ·HS-9817SSK (a mixture of 70% by weight saturated polyester and 30% by weight styrene, acid value 11.5 mg KOH / g, Changxing Materials Industry Co., Ltd.)

[0202] The acid values ​​of (C) acid surfactant and (C') other additives besides (C) acid surfactant are shown in Table 1.

[0203] [Table 1]

[0204]

[0205] <Example 1>

[0206] (Preparation of curable resin compositions)

[0207] 100 parts by mass of styrene diluted bisphenol A type vinyl ester resin synthesized in Synthesis Example 1 as (A) curable resin (containing 52 parts by mass of bisphenol A type vinyl ester resin, 47 parts by mass of styrene, and 1 part by mass of unreacted methacrylic acid), 40 parts by mass of styrene as (B) olefinic unsaturated monomer, 4 parts by mass of BYKW-9010 as (C) acidic surfactant, 560 parts by mass of Softon 1200 as (D) inorganic filler, and 2 parts by mass of Luperox 575 as (E) thermal polymerization initiator were added to a two-wrist kneader and kneaded at 30°C for 15 minutes to produce a curable resin composition.

[0208] (Preparation of solidified materials)

[0209] Using the prepared curable resin composition, a transfer molding machine (model MF-070, Prestige Corporation) was used to heat the resin at a mold temperature of 140°C and a molding pressure of 15 kgf / cm². 2 Curing time was 180 seconds, and a pudding cup-shaped molded product (5 mm in diameter and 3 mm in height on the substrate side) was obtained on a PPS (polyphenylene sulfide) substrate.

[0210] (Evaluation of the adhesion of the cured material to the substrate)

[0211] The resulting molded articles were subjected to a lateral load applied at a constant speed of 2 mm / min using a die shear testing machine (Dieji Co., Ltd.). The shear failure strength was measured five times at 25°C, and the average value was taken as the cohesive force. The results are shown in Table 2.

[0212] <Examples 2-4, Comparative Examples 1-7>

[0213] The types and compositions of the raw materials were changed as described in Table 2, except that the process was the same as in Example 1, to prepare a curable resin composition. Furthermore, the mass parts of Synthesis Example 2 were the total mass parts of (A) the curable resin and the unreacted saturated polyacid. Additionally, the styrene used for diluting (A) the curable resin was removed from the mixing amount of component (A) and included in the mixing amount of (B) the olefinic unsaturated monomer, and this was recorded. Next, a cured product was prepared in the same manner as in Example 1, and its adhesion was evaluated. The results are shown in Table 2.

[0214] <Example 5>

[0215] 100 parts by mass of styrene diluted bisphenol A type vinyl ester resin synthesized in Synthesis Example 1 as (A) curable resin, 40 parts by mass of styrene as (B) olefinic unsaturated monomer, 4 parts by mass of BYK W-9010 and 4 parts by mass of BYK P-9051 as (C) acidic surfactant, 560 parts by mass of Softon 1200 as (D) inorganic filler, 2 parts by mass of Luperox 575 as (E) thermal polymerization initiator, and 30 parts by mass of Taketron as (G) low shrinkage agent were added to a two-wrist kneader and kneaded at 30°C for 15 minutes. Next, 40 parts by mass of ESC03B173 / P9 as (F) glass fiber were added and kneaded further at 30°C for 10 minutes to prepare a curable resin composition. Using the obtained curable resin composition, cured products were prepared in the same manner as in Example 1, and the adhesion was evaluated. The results are shown in Table 2.

[0216] Table 2-1

[0217] Table 2

[0218]

[0219] Table 2-2

[0220] (Continued from Table 2)

[0221]

[0222] The results shown in Table 2 demonstrate that the molded articles of Examples 1-5 exhibit high adhesion to the PPS substrate. It can be considered that by adjusting the acid value of (C) the acidic surfactant, and the acid values ​​of (A) the curable resin, (B) the olefinic unsaturated monomer, (C) the acidic surfactant, and the optionally included saturated polyacid mixture, to a specified range, the wettability to the substrate is improved, resulting in high adhesion.

[0223] On the other hand, in Comparative Examples 1 to 5, which did not use (C) acidic surfactants, the adhesion was low. This can be attributed to the fact that, due to the low acid value of the other additives, an effect of improving the wettability of the substrate could not be expected, or that the other additives volatilized or seeped onto the surface of the molded article due to the influence of the mold temperature and curing heat during curing, resulting in insufficient adhesion.

[0224] In Comparative Examples 6 and 7, where the acid value of the mixture of (A) curable resin, (B) olefinic unsaturated monomer, and optionally a saturated polybasic acid exceeds 12 mg KOH / g, the adhesion was also low. This can be attributed to the fact that (A) curable resin contained a large amount of unreacted monomer during synthesis, which volatilized or leached, affecting adhesion. Furthermore, in Comparative Example 6, the molded article peeled off from the substrate immediately after molding without the application of external force, making it impossible to evaluate adhesion.

[0225] Industry availability

[0226] According to the present invention, a curable resin composition is provided that yields a cured product with excellent adhesion to substrates, particularly difficult-to-bond resin substrates. Furthermore, an electrical and electronic component having a cured product with excellent adhesion as a sealing material is provided, along with a method for manufacturing the same. This curable resin composition is preferably used for sealing and fixing applications in electronic devices such as motors, coils, connectors, and electronic control units mounted in automobiles, as well as wiring boards and electronic components mounted on such wiring boards.

Claims

1. A curable resin composition comprising: (A) Curing resin, (B) Unsaturated olefinic monomers, (C) Acidic surfactants, (D) Inorganic filler materials, (E) Thermal polymerization initiator, and Optional saturated polyacids, The (A) curable resin contains at least (A-1) vinyl ester resin, and the content of (A-1) vinyl ester resin in the (A) curable resin is 75% by mass or more. The mixture of (A) the curable resin, (B) the olefinic unsaturated monomer, and the saturated polybasic acid has an acid value of less than 12 mg KOH / g. The mixture of (A) the curable resin, (B) the olefinic unsaturated monomer, (C) the acidic surfactant, and the saturated polybasic acid has an acid value of 10 mg KOH / g or higher. The acidic surfactant (C) is a low-volatility substance with an acid value of 20 mg KOH / g or higher. Low-volatility substances are those that retain more than 90% of their weight under atmospheric conditions at 150°C for 60 minutes.

2. The curable resin composition according to claim 1, wherein the acid value of the acidic surfactant (C) is 30-190 mg KOH / g.

3. The curable resin composition according to claim 1 or 2, wherein the acidic surfactant (C) is a phosphate ester compound.

4. The curable resin composition according to claim 1 or 2, wherein the (B) olefinic unsaturated monomer is styrene.

5. The curable resin composition according to claim 1 or 2, wherein, Relative to a total of 100 parts by mass of (A) curable resin, (B) olefinic unsaturated monomer, and optionally included saturated polybasic acid, it contains (A) 5-95 parts by weight of curing resin (B) 5-95 parts by weight of olefinic unsaturated monomers (C) 0.1–10 parts by weight of acidic surfactant (D) 200-700 parts by weight of inorganic filler material, and (E) 0.1 to 20 parts by weight of thermal polymerization initiator.

6. The curable resin composition according to claim 1 or 2, further comprising (F) glass fibers.

7. The curable resin composition according to claim 1 or 2, further comprising (G) a low-shrinkage agent.

8. An electrical and electronic component comprising a cured product of the curable resin composition according to any one of claims 1 to 7.

9. A method for manufacturing an electrical and electronic component, comprising the steps of: encapsulating a component of the electrical and electronic component using a curable resin composition according to any one of claims 1 to 7; and heating and curing the curable resin composition.

Images