Alkali-developable resin composition, dry film, cured product, and electronic component having the cured product

Abstract

The present invention provides an alkali-developable resin composition that is low in volatility, excellent in dispersibility, photosensitivity, and developability, has excellent pencil hardness and heat resistance of the cured product, and produces a coating film that is good to the touch dry. The alkali-developable resin composition contains (A) an epoxy resin, (B) a carboxyl group-containing vinyl ester resin, (C) a photopolymerization initiator, (D) a photosensitive monomer, (E) an inorganic filler, (F) a high-boiling point solvent, and (G) a reactive diluent, wherein the (G) reactive diluent comprises at least one selected from a reactive diluent (G-1) with a viscosity of 2 mPa·s or more and 15 mPa·s or less, and a reactive diluent (G-2) with a viscosity greater than 15 mPa·s and 50 mPa·s or less, and the reactive diluent (G-1) with a viscosity of 2 mPa·s or more and 15 mPa·s or less, and the reactive diluent (G-2) with a viscosity greater than 15 mPa·s and 50 mPa·s or less, are epoxy compounds having only one epoxy group per molecule.

Description

Technical Field

[0001] The present invention relates to an alkali-developable resin composition, a dry film, a cured product, and an electronic component having the cured product. In particular, the present invention relates to a low-volatile alkali-developable resin composition, a cured product suitable for a printed wiring board such as a solder resist layer, and an electronic component having the cured product.

Background Art

[0002] In the production of printed wiring boards, curable resin compositions are generally used for forming permanent films such as solder resist layers. Dry film type compositions, liquid compositions, etc. have been developed as such curable resin compositions. Furthermore, in order to apply to miniaturization of electronic components, high-definition design structures, and complex manufacturing methods, it is also expected to pattern curable resin compositions by applying the principle of photolithography, thereby enabling microfabrication. In recent years, from the perspective of environmental measures, alkali-developable types that can be developed with a dilute weak alkali aqueous solution have become mainstream.

[0003] Conventionally, in printed wiring boards, a solder resist layer has been formed using a curable resin composition (also called a solder resist composition or solder resist ink) as a protective material for the circuits of the circuit board. Conventional solder resists use highly volatile low-boiling solvents, and defects such as bubbles and pinholes often occur in applications, and due to their high volatility, the environmental load also increases.

[0004] With increasing environmental concerns, the standards and regulations related to reducing volatile organic compounds (VOCs) are becoming increasingly stringent in the manufacturing process of printed circuit boards, which use many chemicals. Volatile organic compounds are defined as organic compounds with an arbitrary initial boiling point of 250°C or less at a standard pressure of 101.3 kPa (see GB / T 38608-2020). Typically, VOCs can be classified into eight types: alkanes, aromatic hydrocarbons, olefins, halogenated hydrocarbons, esters, aldehydes, ketones, and other compounds. Common VOCs include benzene, toluene, xylene, styrene, trichloroethylene, trichloromethane, trichloroethane, diisocyanates, and toluene diisocyanate.

[0005] Patent Document 1 uses water instead of a high-boiling point solvent to reduce VOCs emissions. However, this solder resist ink has disadvantages such as poor storage stability (the carboxyl groups of the acrylic resin in the ink involved in the development reaction become hydrophilic and are then surrounded by water molecules, and the reaction between the carboxyl groups and the sodium carbonate in the developer is weakened by the surrounding water molecules, thus reducing the developability of the ink, and in severe cases resulting in development stains), and a complex process. In addition, the range of use is limited due to the limitations of the ink's properties. Patent Document 2 uses an eco-friendly solvent (for example, one or more of the following: ethylene glycol butyl ether (boiling point 171°C), divalent acid ester (boiling point 196-225°C), diethylene glycol monobutyl ether (boiling point 230.5°C), ethylene glycol acetate (boiling point 83°C), and propylene glycol methyl ether (boiling point 120°C)), but the total amount of VOCs exceeds 20%. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] CN 108219585A [Patent Document 2] CN 113604103A [Overview of the project] [Problems that the invention aims to solve]

[0007] Conventionally, general developable solder resist compositions typically use aromatic hydrocarbon solvents (such as the heavy aromatic hydrocarbon solvent naphtha S-150) and low-boiling-point ester or ether solvents (e.g., dipropylene glycol monomethyl ether, carbitol acetate). The main problem with these compositions is that they contain over 20% volatile organic compounds (VOCs), posing a significant environmental hazard. Furthermore, because these solvents evaporate quickly, when printing on thick copper plates (e.g., copper thickness of 2 oz (70 μm) or more) or when the print film thickness is thick, bubbles are likely to form, potentially resulting in a poor appearance of the cured film. In addition, solder resist compositions used as protective materials are required to possess excellent ink properties such as dispersibility, photosensitivity, and developability, and their cured products are required to have good pencil hardness and heat resistance, as well as solder heat resistance. Moreover, the coating film is required to have good touch-dry properties so that the cured film (e.g., solder resist layer) has a good appearance.

[0008] Therefore, there is a need to produce an alkali-developable resin composition that ensures excellent ink performance while exhibiting low volatility (VOCs detection value of 10% or less). Furthermore, the cured product exhibits excellent pencil hardness, further improved heat resistance, and excellent touch-dry properties of the coating film.

[0009] From the viewpoint of ink performance, there is a need for an alkali-developable resin composition that is low in volatility and has excellent dispersibility, photosensitivity, and developability (that is, ink performance in this invention mainly refers to the VOCs content, dispersibility, photosensitivity, and developability of the composition). Furthermore, if the formed coating film has excellent touch-drying properties, no tack marks will be formed on the surface of the cured film during exposure. Conversely, if the touch-drying properties are poor, the viscosity of the coating film surface increases, making it easier for tack marks to form on the surface of the coating film during exposure, and also making it easier for marks to form on the surface of the cured film after curing, i.e., the appearance deteriorates.

[0010] Therefore, the present invention aims to provide an alkali-developable resin composition that is low in volatility, has excellent dispersibility, photosensitivity, and developability, exhibits excellent pencil hardness and heat resistance of the cured product, and produces a coating film that is good to the touch-dry.

[0011] Furthermore, the present invention aims to provide dry films and cured products with excellent properties as described above, obtained using such alkali-developable resin compositions, as well as electronic components such as printed circuit boards formed from these dry films and cured products, such as cured coatings like solder resist. [Means for solving the problem]

[0012] As a result of diligent research, the present inventors have found that the above problem can be solved by the following alkali-developable resin composition. The alkali-developable resin composition comprises at least two components, wherein the alkali-developable resin composition contains (A) epoxy resin, (B) carboxyl group-containing vinyl ester resin, (C) photopolymerization initiator, (D) photosensitive monomer, (E) inorganic filler, (F) high boiling point solvent, and (G) reactive diluent. The boiling point of the (F) high-boiling point solvent is greater than 250°C and less than or equal to 280°C. The (G) reactive diluent comprises at least one selected from a reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less, and a reactive diluent (G-2) having a viscosity greater than 15 mPa·s and 50 mPa·s or less, wherein the reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less, and the reactive diluent (G-2) having a viscosity greater than 15 mPa·s and 50 mPa·s or less, are epoxy compounds having only one epoxy group per molecule. We have discovered an alkali-developable resin composition characterized in that, on a solid content basis, per 100 parts by mass of the (B) carboxyl group-containing vinyl ester resin, the content of a reactive diluent (G-1) with a viscosity of 2 mPa·s to 15 mPa·s is greater than 5 parts by mass and less than 25 parts by mass, and the content of a reactive diluent (G-2) with a viscosity of 15 mPa·s to 50 mPa·s is greater than 5 parts by mass and less than 30 parts by mass. This led to the completion of the present invention.

[0013] A preferred embodiment of the present invention relates to an alkali-developable resin composition characterized in that the reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less is the epoxy compound having an unsaturated group, and the reactive diluent (G-2) having a viscosity greater than 15 mPa·s and 50 mPa·s or less is the epoxy compound having an aromatic ring.

[0014] Furthermore, a preferred embodiment of the present invention relates to an alkali-developable resin composition characterized in that, in the above-mentioned two-component system, each component optionally contains a solvent other than the (G) reactive diluent.

[0015] A more preferred embodiment of the present invention relates to an alkali-developable resin composition characterized in that, in the above-mentioned two-component system, the component containing the (G) reactive diluent does not contain any other solvents other than the (G) reactive diluent.

[0016] A more preferred embodiment of the present invention relates to an alkali-developable resin composition characterized in that the reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less is at least one selected from (meth)acrylic acid 3,4-epoxycyclohexylmethyl and glycidyl (meth)acrylate, and the reactive diluent (G-2) having a viscosity greater than 15 mPa·s and 50 mPa·s or less is p-tert-butylphenylglycidyl ether.

[0017] A more preferred embodiment of the present invention relates to an alkali-developable resin composition characterized by having a volatile organic compound content of 10% or less by mass fraction.

[0018] Another aspect of the present invention relates to a dry film obtained by applying the above alkali-developable resin composition to a carrier film and drying it.

[0019] Another aspect of the present invention relates to a cured product obtained by curing the above alkali-developable resin composition.

[0020] Furthermore, another preferred aspect of the present invention relates to a cured product characterized by being obtained by curing the resin layer of the above dry film.

[0021] Another aspect of the present invention relates to an electronic component having the above cured product.

Advantages of the Invention

[0022] According to the present invention, an alkali-developable resin composition can be provided that has low volatility, excellent dispersibility, photosensitivity, and developability, and also has excellent pencil hardness and heat resistance of the cured product formed, and excellent touch dryness of the coating film formed.

[0023] Furthermore, according to the present invention, a dry film and a cured product having excellent characteristics as described above obtained by using such an alkali-developable resin composition, and an electronic component such as a printed wiring board formed from a cured film such as a solder resist as the dry film and the cured product can be provided.

Embodiments for Carrying Out the Invention

[0024] The alkali-developable resin composition of the present invention preferably consists of at least two components. For example, a two-component system is provided in which one resin composition is the main component (main component) and another resin composition is the curing agent component (curing agent composition). In this case, for example, the main component preferably consists of at least (B) a carboxyl group-containing vinyl ester resin, (C) a photopolymerization initiator, (E) an inorganic filler, and (F) a high-boiling point solvent, and the curing agent component preferably consists of at least (A) an epoxy resin, (D) a photosensitive monomer, and (G) a reactive diluent.

[0025] Here, from the viewpoint of preventing chemical reactions during storage, it is preferable that (A) epoxy resin and (B) carboxyl group-containing vinyl ester resin are directly included in each other's compositions, (D) photosensitive monomer and (C) photopolymerization initiator are directly included in each other's compositions, and (G) the component containing the reactive diluent does not contain any solvent other than the reactive diluent (G).

[0026] Furthermore, when (B) a carboxyl group-containing vinyl ester resin and (C) a photopolymerization initiator are included in the same composition, although the detailed mechanism is unknown, poor appearance of the cured film of this composition and coarseness of particles may occur. As a result of our research, we have found that this problem can be improved while reducing the VOCs content by using a main component composition comprising at least (B) a carboxyl group-containing vinyl ester resin, (C) a photopolymerization initiator, and (F) a high-boiling point solvent within a specific boiling point range, and a curing agent composition comprising at least (A) an epoxy resin, (D) a photosensitive monomer, and (G) a reactive diluent.

[0027] The following describes each component constituting the alkali-developable resin composition of the present invention.

[0028] (A) Epoxy resin (A) The epoxy resin functions as a thermosetting component in the alkali-developable resin composition and forms a cured product. As such (A) epoxy resins, known and conventional polyfunctional epoxy resins having at least two epoxy groups in one molecule can be used.

[0029] (A) The epoxy resin may be liquid, solid, or semi-solid. Preferred polyfunctional epoxy resins include, but are not limited to, bisphenol A type epoxy resins, brominated epoxy resins, novolac type epoxy resins, bisphenol F type epoxy resins, hydrogenated bisphenol A type epoxy resins, glycidylamine type epoxy resins, hydantoin type epoxy resins, alicyclic epoxy resins, trihydroxyphenylmethane type epoxy resins, bixylenol type or biphenol type epoxy resins or mixtures thereof, bisphenol S type epoxy resins, bisphenol A novolac type epoxy resins, tetraphenyloleethane type epoxy resins, heterocyclic epoxy resins, diglycidyl phthalate resins, tetraglycidyl xylenoylethane resins, naphthalene group-containing epoxy resins, epoxy resins having a dicyclopentadiene skeleton, glycidyl methacrylate copolymer epoxy resins, copolymer epoxy resins of cyclohexylmaleimide and glycidyl methacrylate, epoxy-modified polybutadiene rubber derivatives, CTBN-modified epoxy resins, and epoxy resins having an isocyanuric ring. These epoxy resins can be used individually or in combination of two or more types.

[0030] (A) The "epoxy resin that is solid or semi-solid at room temperature" in component (A) can also be one of the commonly known and conventional types. For example, epoxy resins that are solid at room temperature include bisphenol A type epoxy resin (JER1001 from Mitsubishi Chemical Corporation, 128E from Nanya Plastics Co., Ltd.), bisphenol F type epoxy resin (JER4004P from Mitsubishi Chemical Corporation), naphthalene type epoxy resin (HP-4700 from DIC Corporation), naphthalene skeleton-containing polyfunctional solid epoxy resin (NC-7000 from Nippon Kayaku Co., Ltd.), naphthalene group-containing epoxy resin (ESN-190, ESN-360 from Nippon Steel Chemical & Material Co., Ltd., HP-4032, EXA-4750, EXA-4700 from DIC Corporation), trisphenol epoxy resin (EPPN-502H from Nippon Kayaku Co., Ltd.), and dicyclopentadiene skeleton-containing polyfunctional solid epoxy resin (Epiclon from DIC Corporation). Examples include HP-7200, HP-7200H), phosphorus-containing epoxy resin (TX0712 manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd.), and tris(2,3-epoxypropyl) isocyanurate (TEPIC manufactured by Nissan Chemical Industries, Ltd.). Examples of epoxy resins that are semi-solid at room temperature include bisphenol A type epoxy resin (jER834 manufactured by Mitsubishi Chemical Corporation) and naphthalene type epoxy resin (HP-4032 manufactured by DIC Corporation).

[0031] Here, in this invention, "solid or semi-solid at room temperature" means that the substance is solid or semi-solid at 15°C. The determination of whether a substance is solid or semi-solid can be made in accordance with the "Method for confirming liquid status" in Appendix 2 of the Ministerial Ordinance Concerning the Testing and Properties of Hazardous Materials (Ministry of Home Affairs Ordinance No. 1 of 1989).

[0032] As the biphenyl-type epoxy resin in component (A), known and conventional polyfunctional epoxy resins having a biphenyl skeleton can be used. Examples include biphenyl skeleton-containing polyfunctional solid epoxy resins (NC-3000H, NC-3000, manufactured by Nippon Kayaku Co., Ltd.) and biphenyl-type epoxy resins (YX-4000, YL-6121HA, manufactured by Mitsubishi Chemical Corporation).

[0033] Examples of novolac-type epoxy resins in component (A) include cresol novolac-type epoxy resin (Epiclon N-690, manufactured by DIC Corporation), phenol-modified novolac-type epoxy resin (Epiclon N-770, manufactured by DIC Corporation; jER152, manufactured by Mitsubishi Chemical Corporation), and bisphenol A novolac-type epoxy resin (BNE200, manufactured by Tiantai High-tech (Guangzhou) Co., Ltd).

[0034] Examples of epoxy resins having an isocyanuric ring in component (A) include isocyanuric acid triglycidyl ester epoxy resin (TGIC-G, manufactured by Shanghai Xindi Chemical Co., Ltd.).

[0035] The content of (A) epoxy resin as described above is preferably in the range of 30 parts by mass or more and 90 parts by mass or less, and more preferably in the range of 40 parts by mass or more and 80 parts by mass or less, per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin, on a solid content basis.

[0036] (B) Carboxyl group-containing vinyl ester resin From the viewpoint of alkali developability, photocurability, and development resistance, the (B) carboxyl group-containing vinyl ester resin used in the present invention is preferably a carboxyl group-containing resin having an ethylenically unsaturated double bond in its molecule. Furthermore, it is more preferable that this unsaturated double bond is derived from acrylic acid or methacrylic acid, or a derivative thereof. Specific examples of (B) carboxyl group-containing vinyl ester resins are shown below. (1) Carboxyl group-containing vinyl ester resin obtained by copolymerization of an unsaturated carboxylic acid such as (meth)acrylic acid with one or more other compounds having an unsaturated double bond; (2) Carboxyl group-containing vinyl ester resin obtained by adding an ethylenically unsaturated group as a pendant group to a copolymer of an unsaturated carboxylic acid such as (meth)acrylic acid and one or more other compounds having an unsaturated double bond, using compounds having epoxy groups and unsaturated double bonds such as glycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylic acid, and (meth)acryloyl chloride; (3) A carboxyl group-containing vinyl ester resin obtained by reacting a copolymer of a compound having epoxy groups and unsaturated double bonds, such as glycidyl (meth)acrylate or 3,4-epoxycyclohexylmethyl (meth)acrylic acid, with an unsaturated carboxylic acid such as (meth)acrylic acid, and then reacting the resulting secondary hydroxyl groups with a polybasic acid anhydride; (4) A carboxyl group-containing vinyl ester resin obtained by reacting a copolymer of an acid anhydride having an unsaturated double bond, such as maleic anhydride, with another compound having an unsaturated double bond, with a compound having a hydroxyl group and an unsaturated double bond, such as 2-hydroxyethyl (meth)acrylate; (5) A carboxyl group-containing vinyl ester resin obtained by reacting a polyfunctional epoxy compound with an unsaturated monocarboxylic acid and reacting the resulting hydroxyl group with a saturated or unsaturated polybasic acid anhydride; (6) A vinyl ester resin containing hydroxyl and carboxyl obtained by reacting a hydroxyl group-containing polymer such as a polyvinyl alcohol derivative with a saturated or unsaturated polybasic acid anhydride, and then reacting the resulting carboxylic acid with a compound having an epoxy group and an unsaturated double bond in one molecule; (7) A carboxyl group-containing vinyl ester resin obtained by reacting a polyfunctional epoxy compound and an unsaturated monocarboxylic acid with a compound having at least one alcoholic hydroxyl group and one reactive group other than an alcoholic hydroxyl group that reacts with an epoxy group in one molecule, with a saturated or unsaturated polybasic acid anhydride; (8) A carboxyl group-containing vinyl ester resin obtained by reacting an unsaturated monocarboxylic acid with a polyfunctional oxetane compound having at least two oxetane rings in one molecule, and reacting the primary hydroxyl group of the resulting modified oxetane resin with a saturated or unsaturated polybasic acid anhydride; and (9) A carboxyl group-containing vinyl ester resin obtained by reacting a bifunctional epoxy compound with an unsaturated monocarboxylic acid and reacting the resulting hydroxyl group with a saturated or unsaturated polybasic acid anhydride; (10) A carboxyl group-containing vinyl ester resin obtained by reacting a polyfunctional epoxy resin such as a phenol novolac type epoxy resin, a cresol novolac type epoxy resin, a bisphenol A cresol novolac type epoxy resin, or a dicyclopentadiene cresol novolac type epoxy resin with (meth)acrylic acid, and adding a dibasic acid anhydride such as phthalic anhydride, tetrahydrophthalic anhydride, or hexahydrophthalic anhydride to the hydroxyl group present in the side chain; (11) A carboxyl group-containing vinyl ester resin obtained by reacting a polyfunctional epoxy resin obtained by further epoxidizing the hydroxyl groups of the polyfunctional epoxy resin of (10) above with epichlorohydrin with (meth)acrylic acid, and adding a polybasic acid anhydride to the resulting hydroxyl groups; (12) A carboxyl group-containing vinyl ester resin obtained by adding a cyclic ether such as ethylene oxide or a cyclic carbonate such as propylene carbonate to a polyfunctional phenol compound such as novolac resin, partially esterifying the resulting hydroxyl group with (meth)acrylic acid, and reacting the remaining hydroxyl group with a polybasic acid anhydride; (13) Carboxyl group-containing vinyl ester resins obtained by adding a compound having one epoxy group and one or more (meth)acryloyl groups in its molecule, such as glycidyl (meth)acrylate or monomethylglycidyl (meth)acrylate, to any of the resins in (10) to (12) above.

[0037] Particularly preferred among these examples are the cresol novolac type and the phenol novolac type, which are the carboxyl group-containing vinyl ester resins of (5), (9), (10), (11), (12), and (13) above.

[0038] In this specification, (meth)acrylate is a general term referring to acrylates, methacrylates, and mixtures thereof, and the same applies to other similar expressions.

[0039] As described above, (B) carboxyl group-containing vinyl ester resins have numerous free carboxyl groups in the side chains of the main chain polymer, and therefore can be developed with dilute alkaline aqueous solutions.

[0040] Furthermore, the acid value of the carboxyl group-containing vinyl ester resin (B) is preferably in the range of 40 to 200 mgKOH / g, and more preferably in the range of 45 to 120 mgKOH / g. If the acid value of the carboxyl group-containing resin is less than 40 mgKOH / g, alkaline development becomes difficult. On the other hand, if it exceeds 200 mgKOH / g, the dissolution of the exposed areas by the developer is promoted, resulting in lines that are thinner than necessary, and the exposed and unexposed areas are dissolved and peeled off by the developer without distinction, which can make it difficult to draw a normal resist pattern, and is therefore undesirable.

[0041] Furthermore, the weight-average molecular weight of the above (B) carboxyl group-containing vinyl ester resin varies depending on the resin skeleton, but is generally preferably in the range of 2,000 to 150,000, and more preferably in the range of 5,000 to 100,000. If the weight-average molecular weight is less than 2,000, the tack-free properties (touch-dry properties) after coating and drying on the substrate will be poor, and furthermore, the moisture resistance of the cured film after exposure may deteriorate, the amount of film obtained during development may decrease, and the resolution may be significantly reduced. On the other hand, if the weight-average molecular weight exceeds 150,000, the developability may deteriorate significantly, and the storage stability may worsen.

[0042] (C) Photopolymerization initiator (C) Examples of photopolymerization initiators include bis-(2,6-dichlorobenzoyl)phenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-2,5-dimethylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-4-propylphenylphosphine oxide, bis-(2,6-dichlorobenzoyl)-1-naphthylphosphine oxide, bis-(2,6-dimethoxybenzoyl)phenylphosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,4,4- Bisacyl phosphine oxides such as trimethylpentyl phosphine oxide, bis-(2,6-dimethoxybenzoyl)-2,5-dimethylphenyl phosphine oxide, and bis-(2,4,6-trimethylbenzoyl)-phenyl phosphine oxide; 2,6-dimethoxybenzoyl diphenyl phosphine oxide, 2,6-dichlorobenzoyl diphenyl phosphine oxide, 2,4,6-trimethylbenzoylphenyl phosphinate methyl ester, and 2-methylbenzoyl diphenyl Monoacyl phosphine oxides such as phosphine oxide, isopropyl pivaloylphenylphosphinate, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, and 2,4,6-trimethylbenzoyl-bis(p-tolyl)phosphine oxide (TMO; (Di-p-tolylphosphoryl)(mesityl)methanone); 1-hydroxycyclohexylphenyl ketone, 1-[4-(2-hydroxyethoxy)-phenyl]-2-hydroxy-2-meth Hydroxyacetophenones such as ru-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]phenyl}-2-methylpropan-1-one, and 2-hydroxy-2-methyl-1-phenylpropan-1-one; benzoins such as benzoin, benzyl, benzoin methyl ether, benzoin ethyl ether, benzoin n-propyl ether, benzoin isopropyl ether, and benzoin n-butyl ether; benzoin alkyl ethers;Benzophenones such as benzophenone, p-methylbenzophenone, Michler's ketone, methylbenzophenone, 4,4'-dichlorobenzophenone, and 4,4'-bis(diethylamino)benzophenone; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone, and 2-methyl-1-[4-(methyl benzophenone). Acetophenones such as [(Phenyl)]-2-morpholino-1-propanone, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholino)phenyl]-1-butanone, and N,N-dimethylaminoacetophenone; thioxanthone, 2-ethylthioxanthone, 2-isopropylthioxanthone, 2,4-dimethylthioxane Thioxanthones such as 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; anthraquinones such as anthraquinone, chloroanthraquinone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-pentylanthraquinone, and 2-aminoanthraquinone; acetophenone dimethyl ketal and benzyl dimethyl ketal Ketals such as 4-(dimethylamino)ethyl benzoate, 2-(dimethylamino)ethyl benzoate, ethyl p-dimethylbenzoate, and other benzoic acid esters; oxime esters such as 1-[4-(phenylthio)phenyl]-1,2-octanedione 2-(O-benzoyl oxime), 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]acetone 1-(O-acetyl oxime); bis(η; 5Examples include titanosenes such as -2,4-cyclopentadien-1-yl)-bis-(2,6-difluoro-3-(1H-pyrrole-1-yl)phenyl)titanium and bis(cyclopentadienyl)-dual[2,6-difluoro-3-(2-(1-pyrrole-1-yl)ethyl)phenyl]titanium; phenyl disulfide 2-nitrofluorene, butyroin, anisoin ethyl ether, azobisisobutyronitrile, and tetramethylthiuram disulfide. The photopolymerization initiator may be used alone or in combination of two or more.

[0043] (C) The content of the photopolymerization initiator is preferably 5 parts by mass or more and 25 parts by mass or less per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin, on a solid content basis. When the content is 5 parts by mass or more, good surface curability is obtained, and when it is 25 parts by mass or less, halation is less likely to occur and good resolution is obtained.

[0044] (D) Photosensitive monomer (D) As the photosensitive monomer, for example, a compound having one or more ethylenically unsaturated groups in the molecule is preferred. Such a (D) photosensitive monomer containing ethylenically unsaturated groups assists in the photocuring of (B) carboxyl group-containing vinyl ester resin by active energy ray irradiation and cures the alkali-developable resin composition.

[0045] The photosensitive monomer (D) that is preferably used in the present invention is, for example, methyl α-(allyloxymethyl)acrylate, or 1,4-butanediol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 1,Diacrylates of diols such as 10-decanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, polypropylene glycol diacrylate, neopentyl glycol diacrylate, diacrylate of diols obtained by adding at least one of ethylene oxide and propylene oxide to neopentyl glycol, diacrylates of diols such as caprolactone-modified hydroxypivalic acid neopentyl glycol diacrylate, EO adduct diacrylate of bisphenol A, PO adduct diacrylate of bisphenol A, tricyclodecanedimethanol diacrylate, hydrogenated dicyclopentadienyl diacrylate, cyclohexyl diacrylate, and other cyclic diacrylates, or methacrylate monomers corresponding thereto. Examples include polyfunctional acrylates such as methacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, trimethylolmethane triacrylate, ethylene oxide-modified trimethylolpropane triacrylate, propylene oxide-modified trimethylolpropane triacrylate, epichlorohydrin-modified trimethylolpropane triacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, tetramethylolmethane tetraacrylate, ethylene oxide-modified phosphate triacrylate, epichlorohydrin-modified glycerol triacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, or silsesquioxane-modified products thereof, or corresponding methacrylate monomers, trifunctional methacrylates, polyfunctional methacrylates such as ε-caprolactone-modified tris(acrooxyethyl) isocyanurate, or combinations of two or more of these.

[0046] The content of such (D) photosensitive monomer is preferably in the range of 2 parts by mass or more and 25 parts by mass or less, and more preferably in the range of 4 parts by mass or more and 20 parts by mass or less, per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin, on a solid content basis. (D) If the content of the photosensitive monomer is within this range, the alkali-developable resin composition will have sufficient photocurability, resulting in better patterning during development and good touch-dry properties.

[0047] (E) Inorganic filler In the present invention, (E) inorganic filler may be used alone or in combination of two or more types. (E) The amount of inorganic filler added is preferably in the range of 35 parts by mass or more and 200 parts by mass or less, and more preferably in the range of 50 parts by mass or more and 150 parts by mass or less, per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin, on a solid content basis. When the amount of inorganic filler added is 35 parts by mass or more, a cured film with better solder heat resistance, insulation reliability, and heat discoloration resistance tends to be obtained. When the amount of inorganic filler added is 200 parts by mass or less, an alkali-developable resin composition with better defoaming properties, resolution, and deep curing properties tends to be obtained.

[0048] (E) Examples of inorganic fillers include titanium dioxide, silica, barium sulfate, barium titanate, Neuburg silica, talc, clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, silicon nitride, and aluminum nitride. Among these, at least one of talc, silica, and barium sulfate is preferred from the viewpoint of improving mechanical properties, heat resistance, and processability. It is preferable that at least the main component contains an inorganic filler, and it is preferable to use barium sulfate as the inorganic filler, as it can suppress curing shrinkage of the cured product of the alkali-developable resin composition and improve properties such as adhesion and hardness.

[0049] (E) Inorganic fillers may be surface-treated, and it is more preferable that their surfaces are surface-treated to allow the introduction of curable reactive groups.

[0050] Here, a curable reactive group refers to a group that undergoes a curing reaction with (A) epoxy resin, (B) carboxyl group-containing vinyl ester resin, etc., and may be either a photocurable reactive group or a thermosetting reactive group. Examples of photocurable reactive groups include methacrylic group, acrylic group, vinyl group, styryl group, etc., while examples of thermosetting reactive groups include epoxy group, amino group, hydroxyl group, carboxyl group, isocyanate group, imino group, oxetanyl group, mercapto group, methoxymethyl group, methoxyethyl group, ethoxymethyl group, ethoxyethyl group, oxazoline group, etc.

[0051] (E) The method for introducing curable reactive groups to the surface of the inorganic filler is not particularly limited and can be introduced using known and conventional methods. The surface of the inorganic filler can be treated with a surface treatment agent having curable reactive groups, for example, a coupling agent having a curable reactive group as an organic group. Examples of coupling agents that can be used include silane coupling agents, titanium coupling agents, zirconium coupling agents, and aluminum coupling agents. Examples of surface-treated inorganic fillers that do not have curable reactive groups include silica-alumina surface treatment, titanate-based coupling agent treatment, aluminate-based coupling agent treatment, and organic treatment of inorganic fillers.

[0052] (E) The average particle size (D50) of the inorganic filler is 2000 nm or less, and more preferably 1200 nm or less. The lower limit is preferably 0.1 nm or more as the average particle size (D50).

[0053] (E) The smaller the average particle size of the inorganic filler, the more diffuse reflection during light irradiation is suppressed, making it easier to perform fine processing of the cured material pattern. The average particle size (D50) can be determined using a laser diffraction particle size distribution analyzer and a dynamic light scattering analyzer. An example of a laser diffraction analyzer is the MicrotracMT3300EXII manufactured by Microtrac-Bell, and an example of a dynamic light scattering analyzer is the Nanotrac Wave II UT151 manufactured by Microtrac-Bell.

[0054] (F) High boiling point solvent The alkali-developable resin composition of the present invention achieves the above objectives of the present invention by using a high-boiling-point solvent, which has a higher boiling point than ordinary solvents, as the main component.

[0055] In detail, the inventors have conducted thorough research and found that in an alkali-developable resin composition, if a (B) carboxyl group-containing vinyl ester resin with a low VOCs content is used as is, and the VOCs content is reduced to 20% or less, the viscosity of the composition increases, making it prone to foaming, which can result in a poor appearance of the cured film. If the boiling point of the solvent is too high (above 280°C), it is difficult to volatilize and there is a lot of residue during pre-baking, resulting in poor touch-drying properties of the coating film.

[0056] Alkali-developable resin compositions utilize high-boiling point solvents within a specific boiling point range of over 250°C and up to 280°C, thereby reducing bubbles during printing and improving appearance defects such as pits and pinholes in the cured film. This ensures the ink performance of the alkali-developable resin composition while significantly reducing environmental impact due to its low volatility.

[0057] Examples of such high-boiling point solvents include one or more selected from polyol ethers, polyol esters, alkyl organic acid esters (esters obtained by reacting organic acids with monohydric alcohols), aliphatic hydrocarbons, and the like. Among these, polyol ethers and polyol esters are preferred, and polyol ethers are even more preferred, from the viewpoint of making it easier to achieve the objectives of the present invention. These high-boiling point solvents may be used individually or in combination of two or more.

[0058] Specific examples of high-boiling-point solvents include, for example, diethylene glycol dibutyl ether (boiling point 254°C), tripropylene glycol n-butyl ether (boiling point 254°C), tetraethylene glycol dimethyl ether (boiling point 275°C), and tripropylene glycol dibutyl ether (boiling point 275°C).

[0059] The content of the high-boiling-point solvent is 40 parts by mass or more and 80 parts by mass or less per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin, more preferably 45 parts by mass or more and 75 parts by mass or less, and even more preferably 50 parts by mass or more and 70 parts by mass or less, on a solid content basis. If the content is too low, the ink performance will be poor. If the content is too high, the touch-drying properties of the coating film tend to be poor. By using a high-boiling-point solvent within the above content range, the alkali-developable resin composition can be made to have excellent ink performance while reducing the VOCs content. When printing on thick copper plates, bubbles are less likely to occur, and the touch-drying properties of the coating film are good, resulting in an excellent appearance of the cured film.

[0060] (G) Reactive diluent The alkali-developable resin composition of the present invention allows for adjustment of the viscosity of the composition by using a reactive diluent (G) having a specific viscosity and specific molecular structure as the curing agent component. This allows for a higher thermal crosslinking density of the ink after curing, and because the reactive diluent (G) participates in the reaction and binds to the cured product, it does not increase the environmental burden as a volatile component. This improves the ink performance of the alkali-developable resin composition, such as dispersibility, photosensitivity, and developability. Furthermore, it is presumed that it further improves the pencil hardness and heat resistance of the cured product and imparts excellent touch-dry properties to the coating film, thereby achieving the above objectives of the present invention.

[0061] In the present invention, the (G) reactive diluent contains an epoxy compound having only one epoxy group in one molecule, and the viscosity of the reactive diluent is 2 mPa·s or more and 50 mPa·s or less.

[0062] The (G) reactive diluent preferably includes at least one of the following: a reactive diluent (G-1) with a viscosity of 2 mPa·s or more and 15 mPa·s or less, and a reactive diluent (G-2) with a viscosity greater than 15 mPa·s and 50 mPa·s or less. In other words, either one may be used alone, or both may be used in combination.

[0063] The reactive diluent (G-1) having a viscosity of 2 mPa·s to 15 mPa·s is an epoxy compound having an unsaturated group, that is, an epoxy compound having an unsaturated group and only one epoxy group per molecule. In this invention, by adding an epoxy active diluent having a specific low viscosity and an unsaturated group to the curing agent component, the reactive activity of the unsaturated group is high, allowing for self-polymerization reactions and copolymerization reactions with other monomers, thereby increasing the photocuring crosslink density of the system. It is presumed that the epoxy group reacts with hydroxyl groups, amino groups, carboxyl groups, or acid anhydrides to introduce more functional groups, improving the thermocuring crosslink density of the system, and further enhancing the ink performance of the composition and the mechanical and physical strength, heat resistance, etc., of the formed cured product.

[0064] From the viewpoint of facilitating the formation of crosslinked structures and improving properties such as strength, the reactive diluent (G-1) having a viscosity of 2 mPa·s to 15 mPa·s is preferably an epoxy compound having an ethylenically unsaturated group and only one epoxy group per molecule, more preferably an epoxy compound having an ethylenically unsaturated group and only one glycidyl group per molecule, and even more preferably a glycidyl ester of an unsaturated monohydric acid. Examples include glycidyl acrylate, glycidyl methacrylate, glycidyl crotonic acid, glycidyl 4-heptenoic acid, glycidyl sorbate, glycidyl linoleate, glycidyl 4-methyl-3-pentenoic acid, glycidyl esters of 3-cyclohexenecarboxylic acid, and glycidyl esters of 4-methyl-3-cyclohexenecarboxylic acid. From the viewpoint of reactivity with groups such as carboxyl groups, compatibility with other components, and dilutability, 3,4-epoxycyclohexylmethyl(meth)acrylate and glycidyl(meth)acrylate are preferred, and glycidyl(meth)acrylate is more preferred. A commercially available glycidyl methacrylate is GMA manufactured by Sigma-Aldrich. The above reactive diluent (G-1) may be used alone or in combination of two or more types.

[0065] As the reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less, a reactive diluent (G-1') having a viscosity greater than 5 mPa·s and less than 12 mPa·s is preferred, and a reactive diluent (G-1'') having a viscosity greater than 7 mPa·s and 10 mPa·s or less is more preferred.

[0066] The reactive diluent (G-2) having a viscosity greater than 15 mPa·s and less than or equal to 50 mPa·s is the epoxy compound having an aromatic ring, that is, an epoxy compound having an aromatic ring and having only one epoxy group per molecule. The present invention is presumed to further enhance the ink performance of the composition and the mechanical and physical strength, heat resistance, etc. of the formed cured product by adding this specific low-viscosity, aromatic ring-containing epoxy reactive diluent to the curing agent component. This is achieved by adding an aromatic ring, thereby increasing the heat resistance of the composition, and by containing rigid chain segments in its structure, having relatively strong diluent ability, high reactive activity, and allowing the epoxy group to react with hydroxyl groups, amino groups, carboxyl groups, or acid anhydrides to introduce more functional groups, thereby improving the thermosetting crosslinking density of the system.

[0067] From the viewpoint of reactivity with groups such as carboxyl groups, and compatibility and dilution with other components, the reactive diluent (G-2) having a viscosity greater than 15 mPa·s and less than or equal to 50 mPa·s is preferably a glycidyl ether substance having an aromatic ring, and more preferably phenylglycidyl ethers in which the phenyl group may be substituted with substituents such as alkyl groups, halogen atoms, amino groups, amine groups, or nitro groups. From the viewpoint of compatibility and dilution with other components, glycidyl ethers in which the phenyl group is substituted with an alkyl group are preferred, and the alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 8 carbon atoms, and even more preferably an alkyl group having 1 to 6 carbon atoms. Examples of reactive diluents (G-2) with a viscosity greater than 15 mPa·s and less than or equal to 50 mPa·s include methylphenyl glycidyl ether, ethylphenyl glycidyl ether, propylphenyl glycidyl ether, butylphenyl glycidyl ether, pentylphenyl glycidyl ether, hexylphenyl glycidyl ether, heptylphenyl glycidyl ether, octylphenyl glycidyl ether, nonylphenyl glycidyl ether, and decylphenyl glycidyl ether. Butylphenyl glycidyl ether is preferred, and p-tert-butylphenyl glycidyl ether is more preferred. Examples of commercially available p-tert-butylphenyl glycidyl ether include XY693 manufactured by Kyokasei Kogyo Co., Ltd. and DENACOL EX-146 manufactured by NagasechemteX. The above reactive diluents (G-2) with a viscosity greater than 15 mPa·s and less than or equal to 50 mPa·s may be used individually or in combination of two or more types.

[0068] As the reactive diluent (G-2) having a viscosity greater than 15 mPa·s and less than or equal to 50 mPa·s, a reactive diluent (G-2') having a viscosity greater than 15 mPa·s and less than 40 mPa·s is preferred, and a reactive diluent (G-2'') having a viscosity greater than 15 mPa·s and less than or equal to 30 mPa·s is more preferred.

[0069] In terms of solid content, the content of the reactive diluent (G-1) with a viscosity of 2 mPa·s or more and 15 mPa·s or less per 100 parts by mass of the above (B) carboxyl group-containing vinyl ester resin is more than 5 parts by mass and less than 25 parts by mass, preferably 6 parts by mass or more and 23 parts by mass or less, more preferably 8 parts by mass or more and 20 parts by mass or less, and even more preferably 10 parts by mass or more and 18 parts by mass or less. In terms of solid content, the content of the reactive diluent (G-2) with a viscosity of more than 15 mPa·s and 50 mPa·s or less per 100 parts by mass of the above (B) carboxyl group-containing vinyl ester resin is more than 5 parts by mass and less than 30 parts by mass, preferably 7 parts by mass or more and 27 parts by mass or less, more preferably 8 parts by mass or more and 25 parts by mass or less, and even more preferably 10 parts by mass or more and 25 parts by mass or less. (G) If the amount of reactive diluent added is too low, the effects of significantly improving dispersibility, photosensitivity, and developability will not be obtained, nor will the heat resistance and pencil hardness of the cured product be further improved, and it may adversely affect the touch-dryness of the coating film and the appearance of the cured film. If the amount added is too high, the viscosity of the system will be low and it will be difficult to disperse, which will adversely affect the dispersibility of the resin composition, developability, touch-dryness of the coating film, and heat resistance of the cured product.

[0070] In this specification, viscosity is measured using a cone-type rotational viscometer (TVE-33H, manufactured by Toki Sangyo Co., Ltd.) under the following conditions: cone rotor 1°34'×R24, rotation speed 100 rpm, 25°C, and 30 seconds.

[0071] In the at least two-component system of the present invention, each component may further contain other solvents other than (G) reactive diluent, such as various common solvents, and it is preferable that the component containing (G) reactive diluent does not contain any other solvents other than (G) reactive diluent. In this way, since (G) reactive diluent itself forms part of the crosslinked structure and there are no other solvents that become VOCs, the VOC content can be reduced and the hardness, heat resistance, etc. of the cured product can be further improved.

[0072] Other solvents In the present invention, for general purposes such as preparing each component system of an alkali-developable resin composition and adjusting its viscosity, at least one component system can be made using a solvent other than the high-boiling point solvent mentioned above.

[0073] Other solvents besides the aforementioned high-boiling point solvents may be ordinary organic solvents. Examples include ketones such as methyl ethyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; glycol ethers such as cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether (DPM), dipropylene glycol diethyl ether, and tripropylene glycol monomethyl ether; esters such as ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate (CA), butyl carbitol acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate; aliphatic hydrocarbons such as octane and decane; and petroleum-based solvents such as petroleum ether, petroleum naphtha, solvent naphtha, and heavy aromatic solvent naphtha. These common organic solvents may be used individually or in combination of two or more.

[0074] The curing agent composition of the alkali-developable resin composition of the present invention preferably does not contain any solvents other than (G) the reactive diluent. Of course, for the purposes of the common art, ordinary solvents may be further used in each component of the system. When ordinary solvents are used, for example, the content of the ordinary solvent per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin is preferably in the range of 2 parts by mass or more and 35 parts by mass or less, and more preferably in the range of 4 parts by mass or more and 25 parts by mass or less, on a solids basis.

[0075] Other ingredients In the alkali-developable resin composition of the present invention, it is of course possible to incorporate further additives as other components as necessary, without departing from the objectives of the present invention.

[0076] Examples of such components include colorants such as pigments and dyes, thermal polymerization inhibitors, thermosetting catalysts, ultraviolet absorbers, plasticizers, flame retardants, antistatic agents, antioxidants, thixotropes, anti-aging agents, antibacterial and antifungal agents, defoaming agents, leveling agents, anti-sagging agents, thickeners, adhesion promoters, thixotropic agents, photoinitiators, sensitizers, photobase generators, thermoplastic resins, elastomers, organic fillers, release agents, surface treatment agents, dispersants, dispersion aids, surface modifiers, stabilizers, phosphors, cellulose resins, and the like. Any known thermosetting catalyst can be used as long as it does not hinder the effects of the present invention. Examples include imidazole derivatives such as imidazole, 2-methylimidazole, 2-ethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 4-phenylimidazole, 1-cyanoethyl-2-phenylimidazole, and 1-(2-cyanoethyl)-2-ethyl-4-methylimidazole; amine compounds such as dicyandiamide, benzyldimethylamine, 4-(dimethylamino)-N,N-dimethylbenzylamine, 4-methoxy-N,N-dimethylbenzylamine, and 4-methyl-N,N-dimethylbenzylamine; hydrazine compounds such as adipic acid dihydrazide and sebacate dihydrazide; and phosphorus compounds such as triphenylphosphine. In addition to these, S-triazine derivatives such as guanamine, acetoguanamine, benzoguanamine, melamine, organic salts of melamine (a reaction product of melamine with organic acids such as phthalic acid), 2,4-diamino-6-methacryloyloxyethyl-S-triazine, 2-vinyl-2,4-diamino-S-triazine, 2-vinyl-4,6-diamino-S-triazine isocyanuric acid adduct, and 2,4-diamino-6-methacryloyloxyethyl-S-triazine isocyanuric acid adduct can also be used. The amount of thermosetting catalyst added is preferably 0.1 parts by mass or more and 20 parts by mass or less, and more preferably 0.5 parts by mass or more and 15 parts by mass or less, per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin, in terms of solid content. In particular, the addition of melamine is preferred. As an antioxidant, melamine suppresses the oxidation of the conductor (copper) on the substrate and improves the adhesion between the substrate and the cured film of the alkali-developable resin composition. As a thermosetting catalyst, it promotes the reaction between epoxy groups and carboxyl groups. This makes it possible to improve properties such as acid resistance, alkali resistance, metal plating resistance, adhesion, and hardness of dry films, cured products, etc., formed from the alkali-developable resin composition.

[0077] In the main component composition and curing agent composition of the alkali-developable resin composition of the present invention, melamine may be added to at least one of them. From the viewpoint of making it easier to achieve the above effects, it is more preferable to add melamine to the curing agent composition. The amount of melamine added is preferably 0.1 parts by mass or more and 20 parts by mass or less, and more preferably 0.5 parts by mass or more and 15 parts by mass or less, per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin, on a solid content basis.

[0078] The main component composition and curing agent composition of the alkali-developable resin composition of the present invention can be prepared by mixing and dispersing these components in predetermined amounts, for example, using a three-roll mill.

[0079] Dry film A dry film can be produced from the alkali-developable resin composition of the present invention. The dry film of the present invention has a resin layer obtained by coating and drying the alkali-developable resin composition of the present invention on a carrier film. When forming a dry film, first, in the case of a two-component system, the main component composition and the curing agent composition are thoroughly mixed to obtain the alkali-developable resin composition of the present invention. Then, either as is, or diluted with a high-boiling point solvent as needed to adjust to an appropriate viscosity, it is applied to the carrier film to a uniform thickness using a comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer roll coater, gravure coater, spray coater, etc. After that, the coated composition can be dried at a temperature of 50 to 130°C for 1 to 30 minutes to form the resin layer. There are no particular restrictions on the coated film thickness, but generally, the film thickness after drying is appropriately selected in the range of 10 to 150 μm, preferably 20 to 60 μm.

[0080] Generally, plastic films are used as carrier films. For example, polyester films such as polyethylene terephthalate (PET), polyimide films, polyamide-imide films, polypropylene films, and polystyrene films can be used. There are no particular restrictions on the thickness of the carrier film, but it is generally selected appropriately within the range of 10 to 150 μm.

[0081] After forming a resin layer made of the alkali-developable resin composition of the present invention on a carrier film, it is preferable to further laminate a peelable cover film on the surface of the resin layer for purposes such as preventing dust from adhering to the surface of the resin layer. Examples of peelable cover films that can be used include polyethylene film, polytetrafluoroethylene film, polypropylene film, and surface-treated paper. The cover film only needs to have an adhesive strength that is weaker than the adhesive strength between the resin layer and the carrier film when the cover film is peeled off.

[0082] In addition, in the present invention, a resin layer may be formed by coating and drying the alkali-developable resin composition of the present invention on the cover film, and then laminating a carrier film on its surface. That is, in the present invention, when manufacturing a dry film, either a carrier film or a cover film may be used as the film to which the alkali-developable resin composition of the present invention is coated.

[0083] Here, the alkali-developable resin composition of the present invention can be adjusted to a viscosity suitable for the coating method using a high-boiling point solvent, applied to a substrate by methods such as dip coating, flow coating, roll coating, bar coating, screen printing, or curtain coating, and then dried (pre-dried) at a temperature of approximately 60 to 100°C to volatilize the high-boiling point solvent contained in the composition, thereby forming a tack-free resin layer. Furthermore, in the case of a dry film in which the above composition is applied to a carrier film or cover film, dried, and wound as a film, the resin layer can be formed by laminating the layer of the composition of the present invention onto the substrate using a laminator or the like so that it comes into contact with the substrate, and then peeling off the carrier film.

[0084] Examples of the above-mentioned substrates include printed circuit boards and flexible printed circuit boards with circuits already formed using copper, etc., as well as copper-clad laminates of all grades (FR-4, etc.) using materials such as paper phenol, paper epoxy, glass cloth epoxy, glass polyimide, glass cloth / nonwoven cloth epoxy, glass cloth / paper epoxy, synthetic fiber epoxy, copper-clad laminates for high-frequency circuits using fluororesin, polyethylene, polyphenylene ether (polyphenylene oxide), cyanate, etc., and metal substrates, polyimide films, PET films, polyethylene naphthalate (PEN) films, glass substrates, ceramic substrates, wafers, etc.

[0085] cured product To form a cured product using the alkali-developable resin composition of the present invention, the composition is applied to a substrate, and after the solvent has evaporated and dried, the resulting resin layer is exposed (irradiated with light) to cure the exposed area (the part that has been irradiated with light). Specifically, by selective exposure with active energy rays through a photomask with a pattern formed on it using a contact or non-contact method, or by direct pattern exposure using a laser direct exposure machine, the unexposed areas are developed with an alkaline aqueous solution (for example, a 0.3-3% by mass sodium carbonate aqueous solution) to form a resist pattern. Furthermore, by heating to a temperature of approximately 100-180°C and performing thermal curing (post-curing), a cured product (cured film) with excellent properties such as heat resistance and pencil hardness can be formed.

[0086] The volatilization drying or thermal curing when forming the above-mentioned cured product can be carried out using, for example, a hot air circulation drying oven, an IR oven, a hot plate, a convection oven, etc. (a method in which hot air inside the dryer is brought into countercurrent contact using a heat source equipped with a steam-heated air heating method, or a method in which hot air is blown onto the support from a nozzle).

[0087] Furthermore, the exposure machine used for the above-mentioned active energy ray irradiation can be any device equipped with a high-pressure mercury lamp, ultra-high-pressure mercury lamp, metal halide lamp, mercury short-arc lamp, etc., that irradiates ultraviolet light in the range of 350 to 450 nm. In addition, a direct writing device (for example, a laser direct imaging device that directly draws images with a laser using CAD data from a computer) can also be used. The lamp light source or laser light source of the direct writing device can have a maximum wavelength in the range of 350 to 410 nm. The exposure amount for image formation varies depending on the film thickness, etc., but is generally 20 to 1000 mJ / cm². 2 Preferably 20-800 mJ / cm² 2 It can be within the range of

[0088] Next, in the development step, the resin layer after the exposure step is treated with a developing solution. This removes the unexposed portions of the resin layer and forms a patterned film of the alkali-developable resin composition of the present invention.

[0089] Here, the dipping method, shower method, spray method, brush method, etc., can be used as the developing process. Typically, a sodium carbonate aqueous solution with a mass concentration of 0.5 to 5% can be used as the developer, but other alkaline aqueous solutions such as potassium hydroxide, sodium hydroxide, potassium carbonate, sodium phosphate, sodium silicate, ammonia, and amines can also be used.

[0090] In this developing process, the developer solution temperature is 20-40°C and the developing time is 180 seconds or less.

[0091] During this development process, the resulting pattern film may be washed with a rinsing solution as needed. Distilled water, methanol, ethanol, isopropyl alcohol, etc., can be used as the rinsing solution, either alone or in combination.

[0092] Electronic components Furthermore, the present invention can also provide an electronic component having the above-mentioned cured product.

[0093] The alkali-developable resin composition or dry film of the present invention can be used as a protective film for printed circuit boards and semiconductor elements, an electrical insulating layer, a sealing material for sealing or embedding electronic components, a component embedding layer, an adhesive layer for fixing electronic components, etc. In particular, it is suitable for high-density wiring requiring low dielectric constant and low dielectric loss tangent, electronic components for processing high-frequency signals, and electronic components for vehicles and robots that require high temperature and long-term reliability.

[0094] In this invention, "electronic components" refers to components used in electronic circuits, and includes not only active components such as printed circuit boards, transistors, light-emitting diodes, and laser diodes, but also passive components such as resistors, capacitors, inductors, and connectors.

[0095] The following examples illustrate one aspect of the present invention, but of course, the purpose is not to limit the scope of the invention claimed in this application.

[0096] Furthermore, unless otherwise specified, the indicated "parts" and "%" are based on mass. [Examples]

[0097] [Synthesis example: Synthesis of carboxyl group-containing vinyl ester resin] 600 g of diethylene glycol dibutyl ether was mixed with 1070 g of o-cresol novolac type epoxy resin (DIC Corporation, Epiclon N-695, softening point 95°C, epoxy equivalent 214, average number of functional groups 7.6) (number of glycidyl groups (total number of aromatic rings): 5.0 mol), 360 g (5.0 mol) of acrylic acid, and 1.5 g of hydroquinone. The mixture was heated to 100°C, stirred, and dissolved uniformly. Next, 4.3 g of triphenylphosphine was added and the mixture was heated to 110°C and reacted for 2 hours, then the temperature was raised to 120°C and the reaction was continued for another 12 hours. 415 g of diethylene glycol dibutyl ether and 456.0 g (3.0 mol) of tetrahydrophthalic anhydride were added to the resulting reaction solution and reacted at 110°C for 4 hours. After cooling, a carboxyl group-containing vinyl ester resin (varnish) was obtained. The solid content concentration of the carboxyl group-containing vinyl ester resin (varnish) obtained in this manner was 65% by mass, and the acid value of the solid content was 89 mgKOH / g. Furthermore, the weight-average molecular weight (Mw) of the obtained carboxyl group-containing vinyl ester resin was 9000. The weight-average molecular weight of the obtained resin was measured by high-performance liquid chromatography using a Shimadzu LC-6AD pump and three Showa Denko K.K. columns, Shodex® KF-804, KF-803, and KF-802.

[0098] [Examples 1-7 and Comparative Examples 1-4] The components shown in Table 1 were pre-mixed in the specified amounts using a mixer, and then kneaded in a three-roll mill to prepare the alkali-developable resin compositions (two-component systems consisting of a main component and a curing agent) of Examples 1-7 and Comparative Examples 1-4, respectively.

[0099] [Table 1]

[0100] Each component listed in Table 1 is explained as follows. *1: Carboxyl group-containing vinyl ester resin obtained in the synthesis example, solids content 65%, solvent component (carbitol acetate (common solvent)) 35%, manufactured by Zhangjiagang Diai Chemical Co., Ltd. *2: Carboxyl group-containing vinyl ester resin obtained in the synthesis example (only the solvent component was changed), solids content 65%, solvent component (diethylene glycol dibutyl ether ((F) high boiling point solvent*18)) 35%, manufactured by Zhangjiagang Diai Chemical Co., Ltd. *3: Organic bentonite: thixotropizer, ORBEN M, manufactured by SHIRAISHI CALCIUM (SHANGHAI) INTERNATIONAL TRADING CO., LTD. *4: Green pigment paste: Base product of 6Y-501, manufactured by TOYOCOLOR CO., LTD. *5: Antioxidant: IRGANOX 1010, manufactured by BASF JAPAN LTD. *6: Thermosetting catalyst DCDA (DICY), manufactured by Shanghai Xindi Chemical Co., Ltd. *7: Antifoaming agent: KSZ-118, manufactured by Zhejiang Shin-Etsu Seisei Kako Co., Ltd. *8: Leveling agent: BYK-1790, manufactured by BYK (Shanghai) Co., Ltd. *9: Photopolymerization initiator: #784 bis(cyclopentadienyl)bis[2,6-difluoro-3-(1-pyrrolyl)phenyl]titanium (Omnirad 784, IGM Resins) *10: Photopolymerization initiator: EAB, 4,4'-bis(diethylamino)benzophenone (manufactured by Daido Chemical Industries, Ltd.) *11: Photopolymerization initiator: ITX, isopropylthioxanthone (manufactured by DKSH JAPAN) *12: Photopolymerization initiator: #907: α-aminoacetophenone-based photopolymerization initiator (Omnirad 907, manufactured by IGM Resins) (2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one) *13: Filler: HD25, talc, manufactured by Tomioka (Shanghai) Trading Co., Ltd. *14: Filler: A2, barium sulfate, manufactured by Foshan Anyi Nanomaterials Co., Ltd. *15: Antifoaming agent: DS-100, manufactured by Foshan City Nankai Ota Chemical Co., Ltd. *16: Anti-sagging agent: BYK-R606, manufactured by BYK (Shanghai) Co., Ltd. *17: Common organic solvent: DPM, dipropylene glycol monomethyl ether, manufactured by Shanghai Hongze Chemical Co., Ltd. (boiling point 190°C) *18: (F) High boiling point organic solvent: Diethylene glycol dibutyl ether, manufactured by Anhui Lixing New Materials Co., Ltd. (boiling point 254℃) *19: Epoxy resin: 128E, manufactured by Nan Ya Plastics, bisphenol A type epoxy resin, 100% solids content *20: Epoxy resin: N-770, manufactured by DIC Corporation, phenol-modified novolac type epoxy resin, 100% solids content *21: Epoxy resin: BNE200, bisphenol A novolac type epoxy resin, manufactured by Tiantai High-tech (Guangzhou) Co., Ltd, solids content 100% *22: Epoxy resin: TGIC-G, manufactured by Shanghai Xindi Chemical Co., Ltd. *23: Photosensitive monomer: DPHA, dipentaerythritol hexaacrylate, manufactured by Nippon Kayaku Co., Ltd. *24: Melamine: MELAMINE-JC, manufactured by Shanghai Xindi Chemical Co., Ltd. *25: Common organic solvent: DPM, dipropylene glycol monomethyl ether, manufactured by Shanghai Hongze Chemical Co., Ltd. (boiling point 190°C) *26: High boiling point organic solvent: Hexadecanol ester, manufactured by Qiaofeng Chemical Technology Co., Ltd., Wuhan City (boiling point 281℃) *27: GMA, glycidyl methacrylate, viscosity 10 mPa·s / 25℃, molecular weight 142.15, boiling point 189℃, manufactured by Sigma-Aldrich. *28: XY693, p-tert-butylphenyl glycidyl ether, viscosity 30 mPa·s / 25℃), molecular weight 206.28, boiling point 175℃, manufactured by Kyokasei Kogyo Co., Ltd.

[0101] For the obtained base compositions, curing agent compositions of the examples and comparative examples, and the alkali-developable resin compositions obtained by mixing them, tests were conducted as follows.

[0102] <VOCs content> When it is predicted that the VOC content (mass%) in the alkali-developable resin composition exceeds 15%, it is measured by the difference method. When it is predicted that the VOC content (mass%) in the alkali-developable resin composition is 15% or less, it is measured by gas chromatography.

[0103] <Dispersibility> Use a scraper fineness meter with a range of 0 - 50 μm. Before measurement, wipe the fineness meter until the solvent has completely evaporated and confirm that there is no residue on the surface. Remove dust on the surface with an antistatic brush. Turn the scale 0 of the measurement table of the fineness meter towards the tester, take a small amount of the sample of the alkali-developable resin composition of the above examples and comparative examples, and place it above the maximum scale. The amount of the sample must be more than the volume of the groove of the fineness meter. The cutting edge of the scraper cuts vertically into the groove of the measurement table, and the fineness meter is pushed down perpendicular to the plane of the fineness meter. Scrape the scraper in the direction of scale 0 at the same speed (about 4 seconds in the whole process).

[0104] Line evaluation Due to the sliding friction between the particles of the test sample and the scraper, a line with a length of about 5 mm or more appears. When three or more lines appear within the same scale range of the same groove, the upper scale line within the scale range with the line is taken as the indication. When the indications of the left and right two grooves do not match, the larger indication is taken as the measurement result.

[0105] Particle evaluation Observe the particles in the groove. When five or more particles appear within the same scale range of the same groove, the upper scale line within the scale range is taken as the indication. When the indications of the left and right two grooves do not match, the larger indication is taken as the measurement result. Judgment criterion: When the line evaluation satisfies less than or equal to 15 μm and the particle evaluation satisfies less than or equal to 35 μm, it is judged that the dispersibility is good "○". Otherwise, it is judged as having poor variability ("×").

[0106] <Dryness to the touch> Each of the alkali-developable resin compositions from the above examples and comparative examples was applied by screen printing to the entire surface of a copper-clad laminate polished with a polishing roller, dried at 80°C for 30 minutes to prepare a substrate, and the touch-dryness of the coating surface was evaluated. ○: Not sticky at all △: Slightly sticky ×: Sticky

[0107] <Sensitivity (Photosensitivity)> After polishing the copper-free substrate using a jet scrubber, it was rinsed with water and dried. The alkali-developable resin compositions of the above examples and comparative examples were then applied by screen printing, and dried in a hot air circulating drying oven at 80°C for 30 minutes. After drying, exposure at 400 mJ / cm² was applied using a step tablet (Kodak No. 2). 2 The sensitivity of the step tablet was evaluated by the number of sensitivity steps remaining after exposure and development with a 1 wt% sodium carbonate aqueous solution at 30°C at a spray pressure of 0.2 MPa for 60 seconds. A higher sensitivity step number indicates better photosensitivity.

[0108] <Developing remaining (developability)> The alkali-developable resin compositions of the above examples and comparative examples were applied to the entire surface of a copper-clad laminate substrate, dried at 75°C for 60 minutes, removed, and allowed to cool at 20°C for 10 minutes to form a resin layer with a thickness of 25 μm. After development using a 1% by mass aqueous sodium carbonate solution at 30°C under a spray pressure of 2 kg for 60 seconds, the residue of the composition on the substrate surface was evaluated. ○: No development remaining △: Some film still needs developing. ×: Severe development residue

[0109] <Pencil hardness> The alkali-developable resin compositions of the above examples and comparative examples were screen-printed onto copper-clad laminate substrates pre-treated by polishing, dried at 80°C for 30 minutes, and cooled to room temperature to form a 25 μm thick resin layer. The resin layer was pattern-exposed using a 7KW conventional halogen exposure machine (ORC HMW-680 GW) equipped with a halogen lamp, and then developed in a 1 wt% sodium carbonate aqueous solution at a pressure of 0.2 MPa and a liquid temperature of 30°C for 60 seconds. After that, the composition was dried (post-cured) in a hot air circulation drying oven at 150°C for 60 minutes to obtain the evaluation substrate. The pencil hardness of the resin (cured product) surface of the evaluation substrate was measured in accordance with JIS K 5600-5-4, and the measurement results are shown in Table 1. The evaluation criteria are as follows: A higher pencil hardness value indicates higher pencil hardness.

[0110] <Heat resistance> The alkali-developable resin compositions of the above examples and comparative examples were screen-printed onto copper-clad laminate substrates that had been pre-treated by polishing, dried at 80°C for 30 minutes, and cooled to room temperature to form a resin layer with a thickness of 25 μm. The resin layer was exposed to 400 mJ / cm² using a 7KW conventional halogen exposure machine (ORC HMW-680 GW) equipped with a halogen lamp. 2 The entire surface was exposed to light, and developed for 60 seconds using a 1% sodium carbonate aqueous solution at 30°C under a spray pressure of 0.2 MPa. Subsequently, the composition was dried (post-cured) for 60 minutes in a hot air circulating drying oven adjusted to 150°C to obtain the evaluation substrate. The evaluation substrates coated with rosin-based flux were immersed in a solder bath set at 288°C, and after cleaning the flux with denatured alcohol, the blistering and peeling of the resist layer (cured product) were visually evaluated. The evaluation criteria are as follows. ◎: If immersion for 10 seconds is repeated 6 or more times, the resist layer (cured material) will swell and peel off. ○: If the immersion is repeated for 10 seconds four or more times but less than six times, the resist layer (cured product) will swell and peel off. △: If immersion for 10 seconds is repeated less than 4 times, the resist layer (cured product) may swell and peel off.

[0111] The results shown in Table 1 indicate that the alkali-developable resin composition of the present invention exhibits excellent dispersibility, photosensitivity, and developability while reducing VOCs content. Furthermore, its cured product has high pencil hardness and excellent heat resistance, and the touch-dry properties of the coating film are further improved.

[0112] On the other hand, the main component composition of Comparative Example 1 contained a normal solvent and did not contain (F) a high-boiling point solvent, so the VOCs content exceeded the standard value. Although the dispersibility and developability of the resin composition were evaluated well, the heat resistance of the cured product was not good. The main component composition of Comparative Example 2 contained (F) a high-boiling point solvent, which significantly reduced the VOCs content. However, because the curing agent composition contained hexadecanol ester, a solvent with a boiling point of 281°C, the dispersibility, photosensitivity, and pencil hardness of the formed cured product were less affected. However, the developability and touch-drying properties of the formed coating film were poorly evaluated, and the heat resistance of the cured product was also poor. The main component composition of Comparative Example 3 contains (F) a high-boiling point solvent and the curing agent composition contains glycidyl methacrylate (GMA), which is a reactive diluent (G-1) with a viscosity of 2 mPa·s to 15 mPa·s. However, in terms of solid content, it contains 25 parts by mass of glycidyl methacrylate (GMA) per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin. As a result, the viscosity of the system is too low, resulting in poor dispersibility, poor touch-drying properties of the formed coating surface, and although the resin composition has excellent photosensitivity, it has poor developability, and furthermore, the heat resistance of its cured product is also poor. The main component composition of Comparative Example 4 contains (F) a high-boiling point solvent, and the curing agent composition contains p-tert-butylphenylglycidyl ether, which is a reactive diluent (G-2) with a viscosity greater than 15 mPa·s and less than or equal to 50 mPa·s. However, in terms of solid content, it contains 30 parts by mass of p-tert-butylphenylglycidyl ether per 100 parts by mass of (B) carboxyl group-containing vinyl ester resin. As a result, the viscosity of the system is low, the dispersibility is poor, the touch-drying properties of the coating surface are also poor, and the photosensitivity of the resin composition and the pencil hardness of its cured product are minimally affected. However, the developability of the resin composition and the heat resistance of its cured product are also poor.

[0113] In contrast, the alkali-developable resin compositions of each example in which (G) reactive diluent was used in an appropriate amount in the curing agent composition not only showed a significant reduction in VOCs content (10% or less), but also further improved dispersibility, photosensitivity, and developability, excellent pencil hardness and heat resistance of the formed cured product, and excellent touch-drying properties of the formed coating film. Furthermore, in Examples 3 and 4, in which the curing agent composition contained only glycidyl methacrylate (GMA), a reactive diluent (G-1) with a viscosity of 2 mPa·s to 15 mPa·s, as (G) reactive diluent, the obtained alkali-developable resin compositions not only had a low VOCs content (7% or less), but also excellent dispersibility and developability, further improved photosensitivity, excellent pencil hardness and heat resistance of the formed cured product, and excellent touch-drying properties of the formed coating film. In Example 7, which includes both GMA, a reactive diluent (G-1) with a viscosity of 2 mPa·s to 15 mPa·s, and XY693, a reactive diluent (G-2) with a viscosity of more than 15 mPa·s and less than 50 mPa·s, in the curing agent composition, the resulting alkali-developable resin composition not only has a low VOCs content (reaching 7% or less), but also excellent dispersibility, developability, and further improved photosensitivity. Furthermore, the formed cured product exhibits excellent pencil hardness and heat resistance, and the resulting coating film is also excellent in terms of tactile drying properties.

[0114] Thus, the alkali-developable resin composition of the present invention has less environmental hazard, superior dispersibility, photosensitivity, and developability, further improved pencil hardness and heat resistance of the formed cured product, and excellent touch-dry properties of the formed coating film. It is particularly suitable for dry films, cured products of printed circuit boards using photolithography, and electronic components having such cured products.

Claims

1. An alkali-developable resin composition comprising at least two-component resin compositions, The alkali-developable resin composition contains (A) epoxy resin, (B) carboxyl group-containing vinyl ester resin, (C) photopolymerization initiator, (D) photosensitive monomer, (E) inorganic filler, (F) high boiling point solvent, and (G) reactive diluent. The boiling point of the (F) high-boiling point solvent is greater than 250°C and less than or equal to 280°C. The (G) reactive diluent comprises at least one selected from a reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less, and a reactive diluent (G-2) having a viscosity greater than 15 mPa·s and 50 mPa·s or less, wherein the reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less, and the reactive diluent (G-2) having a viscosity greater than 15 mPa·s and 50 mPa·s or less, are epoxy compounds having only one epoxy group per molecule. An alkali-developable resin composition characterized in that, on a solid content basis, per 100 parts by mass of the (B) carboxyl group-containing vinyl ester resin, the content of the reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less is more than 5 parts by mass and less than 25 parts by mass, and the content of the reactive diluent (G-2) having a viscosity of 15 mPa·s or more and 50 mPa·s or less is more than 5 parts by mass and less than 30 parts by mass.

2. The alkali-developable resin composition according to claim 1, characterized in that the reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less is an epoxy compound having an unsaturated group, and the reactive diluent (G-2) having a viscosity greater than 15 mPa·s and 50 mPa·s or less is an epoxy compound having an aromatic ring.

3. The alkali-developable resin composition according to claim 1 or 2, characterized in that each component optionally contains a solvent other than the (G) reactive diluent in the at least two-component system.

4. The alkali-developable resin composition according to claim 1 or 2, characterized in that the component containing the (G) reactive diluent does not contain any other solvents other than the (G) reactive diluent in the at least two-component system.

5. The alkali-developable resin composition according to claim 1 or 2, characterized in that the reactive diluent (G-1) having a viscosity of 2 mPa·s or more and 15 mPa·s or less is at least one selected from (meth)acrylic acid 3,4-epoxycyclohexylmethyl and glycidyl (meth)acrylate, and the reactive diluent (G-2) having a viscosity greater than 15 mPa·s and 50 mPa·s or less is p-tert-butylphenylglycidyl ether.

6. The alkali-developable resin composition according to claim 1 or 2, characterized in that the content of volatile organic compounds is 10% or less by mass fraction.

7. A dry film obtained by applying the alkali-developable resin composition according to any one of claims 1 to 6 to a carrier film and drying it.

8. A cured product characterized by being obtained by curing an alkali-developable resin composition according to any one of claims 1 to 6.

9. A cured product characterized by being obtained by curing the resin layer of the dry film described in claim 7.

10. An electronic component characterized by having the cured product described in claim 8 or 9.

Images