Ink for inkjet

Abstract

To provide ink for inkjet which enables production of a cured product having a small average linear thermal expansion coefficient (CTE), can suppress discharge failures, and can suppress precipitation of an inorganic filler.SOLUTION: Ink for inkjet contains (A) an epoxy resin, (B) an inorganic solvent, (C) an inorganic filler, and (D) a surface conditioner, wherein the component (B) contains (B-1) an organic solvent having a boiling point of 135°C or higher and 190°C or lower, the content of the component (B) is 50 mass% or more and 60 mass% or less with respect to 100 mass% of the total component in the ink, the content of the component (D) is 0.15 mass% or more and 1 mass% or less with respect to 100 mass% of the total component obtained by excluding the organic solvent in the ink, and the content of (B-1) the component is 50 mass% or more with respect to 100 mass% of the component (B).SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an inkjet ink, and further to a cured product of the inkjet ink, a resin sheet, a circuit board and a method for producing the same, and a semiconductor device. [Background technology]

[0002] Circuit boards such as printed wiring boards are widely used in various electronic devices. A known method for manufacturing circuit boards is a build-up method in which insulating layers and conductor layers are alternately stacked on an inner layer substrate. One example of the build-up method is a method in which a conductor layer is first formed, and then the conductor layer is covered with an insulating layer and laminated. In such a method, methods for covering the conductor layer with an insulating layer include, for example, lamination, spin coating, curtain coating, dip coating, spray coating, and slit coating. However, these methods have the problem that the insulating layer uniformly covers the entire conductor layer, making it impossible to form an insulating layer only at specific locations on the conductor layer.

[0003] To address the above-mentioned problems, the formation of an insulating layer by an inkjet method has been investigated. With the inkjet method, an insulating layer can be formed only at specific locations on a conductor layer, making it possible to pattern the insulating layer. Methods for forming an insulating layer by the inkjet method are known, for example, from Patent Documents 1 and 2. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-307847 [Patent Document 2] Patent No. 5751438 Summary of the Invention [Problem to be solved by the invention]

[0005] However, when forming an insulating layer using the inkjet method, organic solvents remain when the ink is cured, which can result in poor physical properties of the cured ink (for example, a high average coefficient of linear thermal expansion (CTE)).

[0006] Furthermore, when forming an insulating layer using the inkjet method, ink ejection defects can occur. For example, nozzle clogging can occur due to drying of the nozzles of the inkjet coating device. Furthermore, when the ink used in the inkjet method contains an inorganic filler, the ink may not be ejected from the inkjet coating device. Furthermore, tiny air bubbles (bubble entrapment) can occur in the ink, preventing the ink from being ejected smoothly from the inkjet coating device. Therefore, when forming an insulating layer using the inkjet method, an ink that can suppress ejection defects is required.

[0007] Furthermore, when the ink used in the inkjet method contains an inorganic filler, the inorganic filler in the ink may precipitate. Therefore, when forming an insulating layer by the inkjet method, an ink that can suppress the precipitation of the inorganic filler is required.

[0008] The present invention has been made in view of the above, and has an object to provide an inkjet ink that produces a cured product with a small average coefficient of linear thermal expansion (CTE), is capable of suppressing ejection defects, and is capable of suppressing precipitation of inorganic fillers; a cured product of the ink; a resin sheet including the ink; a circuit board including the cured product of the ink and a method for producing the same; and a semiconductor device including the circuit board. [Means for solving the problem]

[0009] The present inventors have conducted extensive research to solve the above-mentioned problems. As a result, the present inventors have found that the above-mentioned problems can be solved by using an inkjet ink comprising (A) an epoxy resin, (B) an organic solvent, (C) an inorganic filler, and (D) a surface conditioner, wherein the component (B) comprises (B-1) an organic solvent having a boiling point of 135°C or higher and 190°C or lower, the content of the component (B) being 50% by mass or higher and 60% by mass or lower, based on 100% by mass of all components in the ink, the content of the component (D) being 0.15% by mass or higher and 1% by mass or lower, based on 100% by mass of all components in the ink excluding the organic solvent, and the content of the component (B-1) being 50% by mass or higher, based on 100% by mass of the entire ink. This finding led to the completion of the present invention. That is, the present invention includes the following.

[0010] <1> An inkjet ink comprising: (A) an epoxy resin; (B) an organic solvent; (C) an inorganic filler; and (D) a surface conditioner, The component (B) contains (B-1) an organic solvent having a boiling point of 135°C or higher and 190°C or lower, The content of component (B) is 50% by mass or more and 60% by mass or less, based on 100% by mass of all components in the ink; the content of component (D) is 0.15% by mass or more and 1% by mass or less, based on 100% by mass of all components in the ink excluding organic solvents; An inkjet ink, wherein the content of the component (B-1) is 50% by mass or more relative to 100% by mass of the component (B). <2> The component (D) contains a polysiloxane compound (D-1). <1> 1. The inkjet ink according to claim 1. <3> The component (D-1) has a polydialkylsiloxane structure represented by the following formula (d1-1) and a modified polydialkylsiloxane structure represented by the following formula (d1-2) or formula (d1-3): <2> 1. The inkjet ink according to claim 1. [ka] (In formulas (d1-1) to (d1-3), R 11 , R 21 and R 31 each independently represents an alkyl group having 1 to 8 carbon atoms; R 22 and R 32 each independently represents an alkylene group having 1 to 6 carbon atoms; R 23 represents a hydrogen atom or a methyl group; R 24 and R 35 each independently represents an alkyl group or an aralkyl group; R 33 and R 34 each independently represents a divalent hydrocarbon group having 1 to 6 carbon atoms; m and n each independently represent an integer of 3 to 300; * represents a bond.) <4> The average particle size of component (C) is 1 μm or less. <1> ~ <3> 10. The ink-jet ink according to any one of claims 1 to 9. <5> The component (B) further contains one or more organic solvents selected from (B-2) organic solvents having a boiling point of less than 135°C and (B-3) organic solvents having a boiling point of more than 190°C. <1> ~ <4> 10. The ink-jet ink according to any one of claims 1 to 9. <6> The component (B) further contains (B-2) an organic solvent with a boiling point of less than 135°C. <1> ~ <5> 10. The ink-jet ink according to any one of claims 1 to 9. <7> The viscosity measured using an E-type viscometer at 25°C and 50 rpm is 20 mPa·s or less. <1> ~ <6> 10. The ink-jet ink according to any one of claims 1 to 9. <8> The surface tension measured by the hanging drop method at 25°C is 20mN / m or more and 50mN / m or less. <1> ~ <7> 10. The ink-jet ink according to any one of claims 1 to 9. <9> The dielectric loss tangent (Df) of the cured product obtained by thermally curing the ink at 200°C for 90 minutes is 0.005 or less when measured at 5.8 GHz and 23°C. <1> ~ <8> 10. The ink-jet ink according to any one of claims 1 to 9. <10> <1> ~ <9> 10. A cured product of the inkjet ink according to any one of claims 1 to 9. <11> A support and a resin composition layer formed on the support, The resin composition layer is <1> ~ <9> 10. A resin sheet comprising the inkjet ink according to any one of claims 1 to 9. <12> <1> ~ <9> A circuit board comprising a cured product of the ink-jet ink according to any one of claims 1 to 4. <13> <12> A semiconductor device comprising the circuit board according to claim 1. <14> A method for manufacturing a circuit board, comprising: (i) on a substrate, <1> ~ <9> applying the inkjet ink according to any one of the above items by an inkjet method; (ii) forming a resin composition layer by drying the inkjet ink; (iii) forming an insulating layer by curing the resin composition layer; A method for manufacturing a circuit board, comprising: [Effects of the Invention]

[0011] According to the present invention, it is possible to provide an inkjet ink that produces a cured product with a small average coefficient of linear thermal expansion (CTE), that can suppress ejection defects, and that can suppress precipitation of inorganic fillers; a cured product of the ink; a resin sheet containing the ink; a circuit board that includes the cured product of the ink and a method for producing the same; and a semiconductor device that includes the circuit board. DETAILED DESCRIPTION OF THE INVENTION

[0012] The present invention will be described in detail below with reference to embodiments and examples. However, the present invention is not limited to the following embodiments and examples, and can be implemented with any modifications within the scope of the claims of the present invention and their equivalents.

[0013] [Terminology] In the present invention, unless otherwise specified, the boiling point refers to the boiling point under atmospheric pressure (760 mmHg).

[0014] In the present invention, the resin component refers to all of the components in the ink excluding the organic solvent and inorganic filler. Furthermore, the term "100% by mass of the resin component" when referring to the content of each component in the ink means that the total amount of all components in the ink excluding the organic solvent and inorganic filler is 100% by mass.

[0015] [Inkjet ink] The inkjet ink of the present invention comprises (A) an epoxy resin, (B) an organic solvent, (C) an inorganic filler, and (D) a surface conditioner. In the ink, component (B) comprises (B-1) an organic solvent having a boiling point of 135°C or higher and 190°C or lower. The content of component (B) in the ink is 50% to 60% by mass, based on 100% by mass of all components in the ink. The content of component (D) in the ink is 0.15% to 1% by mass, based on 100% by mass of all components in the ink excluding the organic solvent. The content of component (B-1) in the ink is 50% by mass or higher, based on 100% by mass of component (B). This inkjet ink can produce a cured product with a low average coefficient of linear thermal expansion (CTE). This inkjet ink can also suppress ejection defects and inorganic filler precipitation.

[0016] The ink-jet ink of the present invention may further contain, as optional components, (E) a curing agent, (F) a thermoplastic resin, (G) a curing accelerator, and (H) other additives. Each component contained in the ink-jet ink of the present invention will be described in detail below.

[0017] <(A) Epoxy resin> The inkjet ink of the present invention contains, as component (A), an epoxy resin (A). The epoxy resin refers to a curable resin having an epoxy group. The epoxy resin (A) may be used alone or in combination of two or more types.

[0018] Examples of epoxy resins include bisphenol-type epoxy resins, dicyclopentadiene-type epoxy resins, trisphenol-type epoxy resins, naphthol novolac-type epoxy resins, phenol novolac-type epoxy resins, tert-butyl-catechol-type epoxy resins, naphthalene-type epoxy resins, naphthol-type epoxy resins, anthracene-type epoxy resins, glycidylamine-type epoxy resins, glycidyl ester-type epoxy resins, cresol novolac-type epoxy resins, biphenyl-type epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spiro ring-containing epoxy resins, cyclohexane-type epoxy resins, cyclohexanedimethanol-type epoxy resins, naphthylene ether-type epoxy resins, trimethylol-type epoxy resins, and tetraphenylethane-type epoxy resins. Bisphenol-type epoxy resins refer to epoxy resins having a bisphenol structure, such as bisphenol A-type epoxy resins, bisphenol F-type epoxy resins, bisphenol S-type epoxy resins, and bisphenol AF-type epoxy resins. Biphenyl-type epoxy resin refers to an epoxy resin having a biphenyl structure, where the biphenyl structure may have a substituent such as an alkyl group, an alkoxy group, an aryl group, etc. Therefore, bixylenol-type epoxy resins and biphenylaralkyl-type epoxy resins are also included in biphenyl-type epoxy resins.

[0019] The epoxy resin preferably has two or more epoxy groups in one molecule. When the total components of the epoxy resin excluding the organic solvent are taken as 100 mass %, the proportion of the epoxy resin having two or more epoxy groups in one molecule is preferably 50 mass % or more, more preferably 60 mass % or more, and even more preferably 70 mass % or more.

[0020] Epoxy resins include those that are liquid at a temperature of 20°C (hereinafter referred to as "liquid epoxy resins") and those that are solid at a temperature of 20°C (hereinafter referred to as "solid epoxy resins").

[0021] The liquid epoxy resin is preferably a liquid epoxy resin having two or more epoxy groups in one molecule.

[0022] Preferred liquid epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AF type epoxy resins, naphthalene type epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, phenol novolac type epoxy resins, alicyclic epoxy resins such as alicyclic epoxy resins having an ester skeleton, cyclohexane type epoxy resins, cyclohexane dimethanol type epoxy resins, and epoxy resins having a butadiene structure.

[0023] Specific examples of liquid epoxy resins include "HP-4032," "HP-4032-D," and "HP-4032-SS" (naphthalene type epoxy resins) manufactured by DIC Corporation; "828US," "jER828EL," "825," and "Epikote 828EL" (bisphenol A type epoxy resins) manufactured by Mitsubishi Chemical Corporation; "jER807" and "1750" (bisphenol F type epoxy resins) manufactured by Mitsubishi Chemical Corporation; "jER152" (phenol novolac type epoxy resin) manufactured by Mitsubishi Chemical Corporation; and "630" and "630LSD" (glycidylamine type epoxy resins) manufactured by Mitsubishi Chemical Corporation. Examples include "ZX1059" manufactured by Nippon Steel Chemical & Material Co., Ltd. (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin); "EX-721" manufactured by Nagase ChemteX Corporation (glycidyl ester type epoxy resin); "Celloxide 2021P" manufactured by Daicel Corporation (alicyclic epoxy resin with an ester skeleton); "PB-3600" manufactured by Daicel Corporation (epoxy resin with a butadiene structure); and "ZX1658" and "ZX1658GS" (liquid 1,4-glycidylcyclohexane type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.

[0024] As the solid epoxy resin, a solid epoxy resin having three or more epoxy groups in one molecule is preferred, and an aromatic solid epoxy resin having three or more epoxy groups in one molecule is more preferred.

[0025] Preferred solid epoxy resins include bixylenol-type epoxy resins, naphthalene-type epoxy resins, naphthalene-type tetrafunctional epoxy resins, cresol novolac-type epoxy resins, dicyclopentadiene-type epoxy resins, trisphenol-type epoxy resins, naphthol-type epoxy resins, biphenyl-type epoxy resins, naphthylene ether-type epoxy resins, anthracene-type epoxy resins, bisphenol A-type epoxy resins, bisphenol AF-type epoxy resins, and tetraphenylethane-type epoxy resins.

[0026] Specific examples of solid epoxy resins include "HP-4032H" (naphthalene type epoxy resin) manufactured by DIC Corporation; "HP-4700" and "HP-4710" (naphthalene type tetrafunctional epoxy resins) manufactured by DIC Corporation; "N-690" (cresol novolac type epoxy resin) manufactured by DIC Corporation; "N-695" (cresol novolac type epoxy resin) manufactured by DIC Corporation; "HP-7200HH", "HP-7200H", and "HP-7200" (dicyclopentadiene epoxy resins) manufactured by DIC Corporation. DIC Corporation's "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", and "HP6000" (naphthylene ether type epoxy resin); Nippon Kayaku Corporation's "EPPN-502H" (trisphenol type epoxy resin); Nippon Kayaku Corporation's "NC-7000L" (naphthol novolac type epoxy resin); Nippon Kayaku Corporation's "NC-3000H", "NC-3000", and "NC-3000" L, "NC-3100" (biphenyl-type epoxy resin); "ESN-475V" (naphthol-type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "ESN-485" (naphthol novolac-type epoxy resin) manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YX4000H", "YX4000", "YL6121" (biphenyl-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "YX4000HK" (bixylenol-type epoxy resin) manufactured by Mitsubishi Chemical Corporation. Examples of epoxy resins include "YX8800" (anthracene-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "PG-100" and "CG-500" manufactured by Osaka Gas Chemicals Co., Ltd.; "YL7760" (bisphenol AF-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "YL7800" (fluorene-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "jER1010" (solid bisphenol A-type epoxy resin) manufactured by Mitsubishi Chemical Corporation; and "jER1031S" (tetraphenylethane-type epoxy resin) manufactured by Mitsubishi Chemical Corporation.

[0027] The inkjet ink may contain only a liquid epoxy resin as the epoxy resin, only a solid epoxy resin, or a combination of a liquid epoxy resin and a solid epoxy resin. When a liquid epoxy resin and a solid epoxy resin are used in combination, the ratio by mass of the liquid epoxy resin to the solid epoxy resin (liquid epoxy resin:solid epoxy resin) is preferably 1:0.01 to 1:50, more preferably 1:0.05 to 1:20, and even more preferably 1:0.1 to 1:10.

[0028] The epoxy equivalent of the epoxy resin is preferably 50 g / eq to 5,000 g / eq, more preferably 50 g / eq to 3,000 g / eq, even more preferably 80 g / eq to 2,000 g / eq, and even more preferably 110 g / eq to 1,000 g / eq. The epoxy equivalent is the mass of the epoxy resin containing one equivalent of epoxy groups. This epoxy equivalent can be measured according to JIS K7236.

[0029] The weight average molecular weight (Mw) of the epoxy resin is preferably 100 to 5,000, more preferably 250 to 3,000, and even more preferably 400 to 1,500. The Mw of the epoxy resin can be measured as a polystyrene-equivalent value by gel permeation chromatography (GPC).

[0030] The content of component (A) in the ink is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 13% by mass or more or 14% by mass or more, and is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 17% by mass or less, 16% by mass or less, or 15% by mass or less, based on 100% by mass of all components in the ink excluding organic solvents. When the content of component (A) is within the above range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be reduced. Furthermore, when the content of component (A) is within the above range, ink ejection defects can be suppressed, and precipitation of inorganic fillers in the ink can be suppressed.

[0031] The content of component (A) in the ink is preferably 25% by mass or more, more preferably 35% by mass or more, and even more preferably 40% by mass or more, relative to 100% by mass of the resin components in the ink, and is preferably 60% by mass or less, more preferably 50% by mass or less, and even more preferably 45% by mass or less or 43% by mass or less. When the content of component (A) is within the above range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be reduced. Furthermore, when the content of component (A) is within the above range, ink ejection defects can be suppressed, and precipitation of inorganic fillers in the ink can be suppressed.

[0032] <(B) Organic solvent> The inkjet ink of the present invention contains an organic solvent (B) as component (B). The organic solvent (B) does not include those corresponding to the above-mentioned component (A). The organic solvent (B) may be used alone or in combination of two or more.

[0033] (B) The organic solvent includes, for example, aromatic solvents and non-aromatic solvents.

[0034] Aromatic solvents are solvents that contain an aromatic ring in the molecule. Examples of aromatic solvents include C benzene (boiling point 80°C), toluene (boiling point 110°C), o-xylene (boiling point 144°C), m-xylene (boiling point 139°C), p-xylene (boiling point 138°C), and ethylbenzene (boiling point 136°C). 6-8Aromatic hydrocarbons, C9 aromatic hydrocarbons such as 1,2,3-trimethylbenzene (boiling point 176°C), 1,3,5-trimethylbenzene (boiling point 165°C), 1,2,4-trimethylbenzene (boiling point 169°C), 4-ethyltoluene (boiling point 161°C), 3-ethyltoluene (boiling point 160°C), 2-ethyltoluene (boiling point 166°C), isopropylbenzene (boiling point 152°C), n-propylbenzene (boiling point 159°C), indane (boiling point 176°C), n-butylbenzene (boiling point 183°C), isobutylbenzene (boiling point 172°C), sec-butylbenzene (boiling point 173°C), tert-butylbenzene (boiling point 1 69°C), 1,2-diethylbenzene (boiling point 184°C), 1,3-diethylbenzene (boiling point 181°C), 1,4-diethylbenzene (boiling point 183°C), 3-ethyl-o-xylene (boiling point 194°C), 4-ethyl-o-xylene (boiling point 190°C), 2-ethyl-p-xylene (boiling point 187°C), 1-methyl-2-isopropylbenzene (boiling point 178°C), 1-methyl-3-isopropylbenzene (boiling point 175°C), 1-methyl-4-isopropylbenzene (boiling point 177°C), 1,2,3,5-tetramethylbenzene (boiling point 198°C), 1,2,3,4-tetrahydronaphthalene (boiling point 207°C), etc. 10 C such as aromatic hydrocarbons, 1,3-dimethyl-4-isopropylbenzene (boiling point 199°C), 1-ethyl-4-isopropylbenzene (boiling point 197°C) 11 C such as aromatic hydrocarbons, 1,4-diisopropylbenzene (boiling point 210°C) 12 Examples of suitable aromatic hydrocarbon solvents include aromatic hydrocarbons; aromatic ketone solvents such as acetophenone (boiling point 202°C); aromatic alcohol solvents such as benzyl alcohol (boiling point 205°C) and phenethyl alcohol (boiling point 219-221°C); aromatic ether solvents such as anisole (boiling point 154°C), phenetole (boiling point 169°C), and phenyl glycol (boiling point 244°C); and aromatic ester solvents such as methyl benzoate (boiling point 198-200°C) and ethyl benzoate (boiling point 211-213°C).

[0035] Non-aromatic solvents are solvents that do not contain an aromatic ring in the molecule, and examples of non-aromatic solvents include glycol-based solvents, glycol ether-based solvents, glycol ether ester-based solvents, aliphatic hydrocarbon-based solvents, aliphatic ketone-based solvents, aliphatic ester-based solvents, aliphatic ether-based solvents, aliphatic alcohol-based solvents, nitrile-based solvents, amide-based solvents, and urea-based solvents.

[0036] Examples of glycol-based solvents include ethylene glycol (boiling point 197°C), diethylene glycol (boiling point 244°C), propylene glycol (boiling point 188°C), dipropylene glycol (boiling point 232°C), and trimethylene glycol (boiling point 211-217°C).

[0037] Examples of glycol ether solvents include cellosolves such as ethylene glycol monomethyl ether (also known as methyl cellosolve) (boiling point 124°C), ethylene glycol monoethyl ether (also known as cellosolve) (boiling point 135°C), ethylene glycol monopropyl ether (also known as propyl cellosolve) (boiling point 151°C), ethylene glycol monobutyl ether (also known as butyl cellosolve) (boiling point 171°C), ethylene glycol monoisobutyl ether (also known as isobutyl cellosolve) (boiling point 160°C), ethylene glycol mono-tert-butyl ether (also known as tert-butyl cellosolve) (boiling point 152°C), and ethylene glycol monohexyl ether (boiling point 208°C); diethylene glycol monomethyl ether (also known as methyl carbitol) (boiling point 193°C), and diethylene glycol monoethyl ether (also known as carbitol) (boiling point 196°C). carbitols such as diethylene glycol monopropyl ether (also known as propyl carbitol) (boiling point 212-216°C), diethylene glycol monobutyl ether (DB) (also known as butyl carbitol) (boiling point 230°C); propylene glycol ethers such as propylene glycol monomethyl ether (PGM) (boiling point 120°C), propylene glycol monoethyl ether (boiling point 132°C), propylene glycol monopropyl ether (boiling point 150°C), and propylene glycol monobutyl ether (boiling point 170°C); dipropylene glycol ethers such as dipropylene glycol monomethyl ether (boiling point 188°C), dipropylene glycol monoethyl ether (boiling point 198°C), dipropylene glycol monopropyl ether (boiling point 210°C), and dipropylene glycol monobutyl ether (boiling point 215°C).

[0038] Examples of glycol ether ester solvents include cellosolve esters such as ethylene glycol monomethyl ether acetate (also known as methyl cellosolve acetate) (boiling point 145°C), ethylene glycol monoethyl ether acetate (also known as cellosolve acetate) (boiling point 156°C), and ethylene glycol monobutyl ether acetate (also known as butyl cellosolve acetate) (boiling point 191°C); diethylene glycol monoethyl ether acetate (EDGAc) (also known as carbitol acetate) ( carbitol esters such as diethylene glycol monobutyl ether acetate (also known as butyl carbitol acetate) (boiling point 217°C) and diethylene glycol monobutyl ether acetate (boiling point 247°C); propylene glycol ether esters such as propylene glycol monomethyl ether acetate (PGMEA) (boiling point 146°C) and propylene glycol monoethyl ether acetate (boiling point 160°C); and dipropylene glycol ether esters such as dipropylene glycol monomethyl ether acetate (boiling point 200°C).

[0039] Examples of aliphatic hydrocarbon solvents include n-pentane (boiling point 36°C), n-hexane (boiling point 69°C), 2-methylpentane (also known as isohexane) (boiling point 60-62°C), n-heptane (boiling point 98°C), n-octane (boiling point 125°C), cyclopentane (boiling point 49°C), cyclohexane (boiling point 81°C), methylcyclohexane (boiling point 101°C), and ethylcyclohexane (boiling point 132°C).

[0040] Examples of aliphatic ketone solvents include aliphatic acyclic ketones such as acetone (boiling point 56°C), methyl ethyl ketone (MEK) (boiling point 79°C), diethyl ketone (boiling point 101°C), 2-pentanone (boiling point 101°C), methyl isobutyl ketone (boiling point 116°C), 2-hexanone (boiling point 127°C), 2-heptanone (MAK) (boiling point 151°C), and diisobutyl ketone (boiling point 168°C); and aliphatic cyclic ketones such as cyclopentanone (boiling point 131°C), cyclohexanone (boiling point 155°C), and 2-methylcyclohexanone (boiling point 162°C).

[0041] Aliphatic ester solvents are non-aromatic solvents having an ester structure that do not fall under the category of glycol ether ester solvents, and examples thereof include methyl acetate (boiling point 57°C), ethyl acetate (boiling point 77°C), n-propyl acetate (boiling point 96°C), isopropyl acetate (boiling point 89°C), n-butyl acetate (boiling point 126°C), isobutyl acetate (boiling point 118°C), sec-butyl acetate (boiling point 112°C), tert-butyl acetate (boiling point 97°C), n-pentyl acetate (boiling point 149°C), isopentyl acetate (boiling point 142°C), propyl acetate (boiling point 149 ... Examples of suitable hydroxy acid alkyl esters include methyl lactate (boiling point 144-145°C), ethyl lactate (boiling point 151-155°C), and butyl lactate (boiling point 185-187°C); keto acid alkyl esters include methyl acetoacetate (boiling point 170°C) and ethyl acetoacetate (boiling point 184°C); and lactones such as γ-butyrolactone (GBL) (boiling point 204°C).

[0042] Aliphatic ether solvents are non-aromatic solvents having an ether structure that do not fall under the category of glycol ether solvents or glycol ether ester solvents, and examples thereof include aliphatic acyclic ethers such as diethyl ether (boiling point 34°C), diisopropyl ether (boiling point 68°C), and methyl tert-butyl ether (boiling point 55°C); and aliphatic cyclic ethers such as tetrahydrofuran (boiling point 66°C), 1,4-dioxane (boiling point 101°C), and 1,3-dioxolane (boiling point 75°C).

[0043] Aliphatic alcohol solvents are non-aromatic solvents with an alcohol structure that does not fall under the category of glycol solvents or glycol ether solvents. Examples include methanol (boiling point 64°C), ethanol (boiling point 78°C), n-propanol (boiling point 97°C), isopropanol (boiling point 82°C), n-butyl alcohol (boiling point 117°C), isobutyl alcohol (also known as isobutanol) (boiling point 108°C), sec-butyl alcohol (boiling point 99°C), tert-butyl alcohol (boiling point 82°C), n-pentyl alcohol (boiling point 138°C), and isopropyl alcohol. Examples of the alcohols include aliphatic acyclic alcohols such as isopentyl alcohol (boiling point 131°C), sec-pentyl alcohol (boiling point 119°C), tert-pentyl alcohol (boiling point 102°C), neopentyl alcohol (boiling point 113°C), n-hexyl alcohol (boiling point 157°C), n-heptyl alcohol (boiling point 175°C), isoheptyl alcohol (boiling point 159°C), n-octyl alcohol (boiling point 195°C), and 2-ethylhexyl alcohol (boiling point 184°C); and aliphatic cyclic alcohols such as cyclohexanol (boiling point 161°C).

[0044] Examples of nitrile solvents include acetonitrile (boiling point: 82°C) and propionitrile (boiling point: 97°C).

[0045] Examples of amide solvents include acyclic amides such as N,N-dimethylformamide (DMF) (boiling point 153°C) and N,N-dimethylacetamide (DMA) (boiling point 165°C); and cyclic amides such as N-methyl-2-pyrrolidone (NMP) (boiling point 202°C).

[0046] Examples of urea-based solvents include acyclic ureas such as tetramethylurea (boiling point 176°C) and cyclic ureas such as 1,3-dimethyl-2-imidazolidinone (DMI) (boiling point 220°C) and N,N'-dimethylpropyleneurea (DMPU) (boiling point 246°C).

[0047] In the inkjet ink of the present invention, the (B) organic solvent includes (B-1) an organic solvent having a boiling point of 135°C or higher and 190°C or lower. The (B-1) organic solvent having a boiling point of 135°C or higher and 190°C or lower as the (B-1) component may be an aromatic solvent, a non-aromatic solvent, or a mixture (mixed solvent) of an aromatic solvent and a non-aromatic solvent. The (B-1) organic solvent having a boiling point of 135°C or higher and 190°C or lower may be used alone or in combination of two or more.

[0048] The boiling point of component (B-1) is not particularly limited as long as it is 135°C or higher and 190°C or lower, but is preferably 180°C or lower, more preferably 170°C or lower, and even more preferably 160°C or lower. When the upper limit of the boiling point of component (B-1) is within the above range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be reduced. Furthermore, when the upper limit of the boiling point of component (B-1) is within the above range, ink ejection defects can be suppressed and precipitation of inorganic fillers in the ink can be suppressed.

[0049] The content of component (B-1) is 50% by mass or more, preferably 55% by mass or more, more preferably 60% by mass or more, 65% by mass or more, or 70% by mass or more, based on 100% by mass of component (B). The upper limit of the content may be 100% by mass, or may be less than 100% by mass, 95% by mass or less, 90% by mass or less, or 85% by mass or less. When the content of component (B-1) is within the above range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be reduced. Furthermore, when the content of component (B-1) is within the above range, ink ejection defects can be suppressed, and precipitation of inorganic fillers in the ink can be suppressed.

[0050] The content of component (B-1) is preferably 26% by mass or more, more preferably 28% by mass or more, and even more preferably 30% by mass or more, 32% by mass or more, 34% by mass or more, or 35% by mass or more, based on 100% by mass of all components in the ink. The upper limit of the content is preferably 55% by mass or less, more preferably 54% by mass or less, 52% by mass or less, or 50% by mass or less. When the content of component (B-1) is within the above range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be reduced. Furthermore, when the content of component (B-1) is within the above range, ink ejection defects can be suppressed, and precipitation of inorganic fillers in the ink can be suppressed.

[0051] In one embodiment, the (B) organic solvent may further contain, in addition to a predetermined amount of the (B-1) component, one or more organic solvents selected from (B-2) an organic solvent having a boiling point of less than 135° C. and (B-3) an organic solvent having a boiling point of more than 190° C. The (B) organic solvent further containing one or more organic solvents selected from (B-2) an organic solvent having a boiling point of less than 135° C. (hereinafter sometimes referred to as "the (B-2) component") and (B-3) an organic solvent having a boiling point of more than 190° C. (hereinafter sometimes referred to as "the (B-3) component") can improve the compatibility of the resin components in the ink, thereby further suppressing ink ejection defects.

[0052] The boiling point of component (B-2) is not particularly limited, but is preferably at least 50° C., more preferably at least 60° C., and even more preferably at least 70° C. When the lower limit of the boiling point of component (B-2) is within the above range, ink ejection defects can be further suppressed.

[0053] The boiling point of component (B-3) is not particularly limited, but is preferably not more than 270° C., more preferably not more than 260° C., and even more preferably not more than 250° C. When the upper limit of the boiling point of component (B-3) is within the above range, ink ejection defects can be further suppressed.

[0054] In such an embodiment, the content of component (B-2) in the ink is preferably 40% by mass or more, 50% by mass or more, 60% by mass or more, 70% by mass or more, or 80% by mass or more, relative to 100% by mass of the total of components (B-2) and (B-3), and the upper limit thereof may be 100% by mass, but may be, for example, 99% by mass or less, 98% by mass or less, etc.

[0055] In this embodiment, the content of component (B-3) in the ink is preferably 25% by mass or less, 20% by mass or less, 15% by mass or less, 10% by mass or less, or 5% by mass or less, relative to 100% by mass of component (B). The lower limit may be 0% by mass, for example, 0.01% by mass or more, 0.1% by mass or more, etc. Furthermore, when the content of component (B-3) is within the above range, the ink can be dried quickly after application while preventing the nozzle of the inkjet coating device from drying out, thereby providing an ink suitable for inkjet printing. Furthermore, when the content of component (B-3) is within the above range, the amount of organic solvent remaining in the cured product of the ink can be reduced, thereby preventing an increase in the average coefficient of linear thermal expansion (CTE) of the cured product of the ink.

[0056] In a preferred embodiment, the (B) organic solvent further contains (B-2) an organic solvent having a boiling point of less than 135°C in addition to a predetermined amount of the (B-1) component. The (B) organic solvent further containing the (B-2) component can improve the compatibility of the resin components in the ink, thereby further suppressing ink ejection defects. Furthermore, the (B) organic solvent further containing the (B-2) component can prevent the nozzle of the inkjet coating device from drying out while quickly drying the ink after coating, thereby providing an ink suitable for the inkjet method.

[0057] In this embodiment, the content of component (B-2) in the ink is typically less than 50% by mass, preferably 47% by mass or less, more preferably 45% by mass or less, and even more preferably 43% by mass or less, relative to 100% by mass of component (B). When the content of component (B-2) is within the above range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be reduced. Furthermore, when the content of component (B-2) is within the above range, ink ejection defects can be further suppressed.

[0058] The content of component (B) in the ink is 50% by mass or more and 60% by mass or less, based on 100% by mass of all components in the ink. The lower limit of this content is preferably 52% by mass or more, more preferably 54% by mass or more. The upper limit of this content is preferably 58% by mass or less, more preferably 56% by mass or less. When the content of component (B) is within this range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be improved. Furthermore, when the content of component (B) is within this range, ink ejection defects can be suppressed, and precipitation of inorganic fillers in the ink can be suppressed.

[0059] <(C) Inorganic filler> The inkjet ink of the present invention contains an inorganic filler (C) as component (C). The inorganic filler (C) is contained in the ink in the form of particles, and is contained in the cured product while maintaining this particulate form. The inorganic filler (C) may be used alone or in combination of two or more types.

[0060] Inorganic compounds can be used as inorganic filler materials. Examples of inorganic filler materials include silica, alumina, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium titanate zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, silica and alumina are preferred, and silica is particularly preferred. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, and hollow silica. Furthermore, spherical silica is preferred.

[0061] Commercially available inorganic fillers include, for example, "SP60-05" and "SP507-05" manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YC100C," "YA050C," "YA050C-MJE," "YA010C," "SC2500SQ," "SO-C4," "SO-C2," and "SO-C1" manufactured by Admatechs Co., Ltd.; "UFP-30," "DAW-03," and "FB-105FD" manufactured by Denka Co., Ltd.; "Silfil NSS-3N," "Silfil NSS-4N," and "Silfil NSS-5N" manufactured by Tokuyama Corporation; "CellSpheres" and "MGH-005" manufactured by Taiheiyo Cement Corporation; and "Hipressica FH" manufactured by Ube Exsymo Co., Ltd.

[0062] The average particle size of the inorganic filler is not particularly limited, but is preferably 1 μm or less, more preferably 0.7 μm or less, and even more preferably 0.5 μm or less. The lower limit of the average particle size is not particularly limited, but is preferably 0.01 μm or more, more preferably 0.03 μm or more, and even more preferably 0.05 μm or more. The average particle size of the inorganic filler can be measured by a laser diffraction / scattering method based on Mie scattering theory. Specifically, a particle size distribution of the inorganic filler on a volume basis is prepared using a laser diffraction / scattering particle size distribution analyzer, and the median diameter is used as the average particle size. The measurement sample can be prepared by weighing 100 mg of inorganic filler and 10 g of methyl ethyl ketone into a vial and ultrasonically dispersing the mixture for 10 minutes. The volume-based particle size distribution of the inorganic filler was measured using a laser diffraction particle size distribution analyzer with blue and red wavelength light sources using a flow cell system, and the average particle size was calculated as the median diameter from the obtained particle size distribution. An example of a laser diffraction particle size distribution measuring device is the "LA-960" manufactured by Horiba, Ltd.

[0063] The specific surface area of ​​the inorganic filler is not particularly limited, but is preferably 0.1 m 2 / g or more, more preferably 0.5m 2 / g or more, more preferably 1m 2 / g or more, 3m 2 / g or more or 5m 2 The upper limit of the specific surface area is not particularly limited, but is preferably 100 m 2 / g or less, more preferably 80m 2 / g or less, more preferably 60m 2 / g or less, 50m 2 / g or less or 40m 2 The specific surface area of ​​the inorganic filler is obtained by adsorbing nitrogen gas onto the surface of a sample using a specific surface area measuring device (Mountech Co., Ltd.'s "Macsorb HM-1210") in accordance with the BET method, and then calculating the specific surface area using the BET multipoint method.

[0064] The inorganic filler is preferably surface-treated with an appropriate surface treatment agent. Surface treatment can enhance the moisture resistance and dispersibility of the inorganic filler. Examples of surface treatment agents include silane coupling agents such as vinyl silane coupling agents, epoxy silane coupling agents, styryl silane coupling agents, (meth)acrylic silane coupling agents, amino silane coupling agents, isocyanurate silane coupling agents, ureido silane coupling agents, mercapto silane coupling agents, isocyanate silane coupling agents, and acid anhydride silane coupling agents; non-silane coupling alkoxysilane compounds such as methyltrimethoxysilane and phenyltrimethoxysilane; and silazane compounds. The surface treatment agents may be used alone or in combination of two or more.

[0065] Examples of commercially available surface treatment agents include "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM803" (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBE903" (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., and "SZ-31" (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd.

[0066] The degree of surface treatment with the surface treatment agent is preferably within a predetermined range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, 100% by mass of the inorganic filler is preferably surface-treated with 0.2 to 5% by mass of the surface treatment agent.

[0067] The degree of surface treatment with the surface treatment agent can be evaluated by the amount of carbon per unit surface area of ​​the inorganic filler. From the viewpoint of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of ​​the inorganic filler is set to 0.02 mg / m 2 More than 0.1 mg / m is preferable. 2 More preferably, 0.2 mg / m or more 2On the other hand, the upper limit of the amount of carbon per unit surface area of ​​the inorganic filler is 1 mg / m from the viewpoint of preventing an increase in the melt viscosity of the ink or the melt viscosity in the form of a sheet. 2 Less than 0.8 mg / m is preferred 2 Less than 0.5 mg / m is more preferable. 2 The following is even more preferred. The carbon amount per unit surface area of ​​the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (e.g., methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler that has been surface-treated with a surface treatment agent, and ultrasonic cleaning is performed at 25°C for 5 minutes. After removing the supernatant and drying the solid content, the carbon amount per unit surface area of ​​the inorganic filler can be measured using a carbon analyzer. The carbon analyzer that can be used is the "EMIA-320V" manufactured by Horiba, Ltd.

[0068] The content of component (C) in the ink is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 65% ​​by mass or more, and preferably 80% by mass or less, more preferably 75% by mass or less, and even more preferably 70% by mass or less, based on 100% by mass of all components in the ink excluding organic solvents. When the content of component (C) is within the above range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be reduced. Furthermore, when the content of component (C) is within the above range, ink ejection defects can be suppressed, and precipitation of inorganic fillers in the ink can be suppressed.

[0069] <(D) Surface conditioner> The inkjet ink of the present invention contains a (D) surface conditioner as component (D). A surface conditioner refers to a compound that reduces the surface tension of the ink. The (D) surface conditioner does not include those that fall under the above-mentioned components (A) to (C). The (D) surface conditioner may be used alone or in combination of two or more types.

[0070] Examples of the (D) surface conditioner include polysiloxane compounds, poly(meth)acrylate compounds, and compounds in which some or all of the hydrogen atoms in polysiloxane compounds or poly(meth)acrylate compounds have been substituted with fluorine atoms. Among these, the (D) surface conditioner preferably contains a (D-1) polysiloxane compound.

[0071] In a preferred embodiment, the (D-1) polysiloxane compound preferably has a polydialkylsiloxane structure represented by the following formula (d1-1) and a modified polydialkylsiloxane structure represented by the following formula (d1-2) or formula (d1-3):

[0072] [ka]

[0073] (In formulas (d1-1) to (d1-3), R 11 , R 21 and R 31 each independently represents an alkyl group having 1 to 8 carbon atoms; R 22 and R 32 each independently represents an alkylene group having 1 to 6 carbon atoms; R 23 represents a hydrogen atom or a methyl group; R 24 and R 35 each independently represents an alkyl group or an aralkyl group; R 33 and R 34 each independently represents a divalent hydrocarbon group having 1 to 6 carbon atoms; m and n each independently represent an integer of 3 to 300; * represents a bond.)

[0074] In formula (d1-1), R 11are each independently an alkyl group having 1 to 8 carbon atoms. The alkyl group may be either linear or branched. Examples of the alkyl group having 1 to 8 carbon atoms include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, and octyl. Among these, R 11 is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group.

[0075] In formula (d1-2), R 21 are each independently an alkyl group having 1 to 8 carbon atoms. The alkyl group may be either linear or branched. The alkyl group having 1 to 8 carbon atoms is as described above. Among them, R 21 is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group.

[0076] In formula (d1-2), R 22 are each independently an alkylene group having 1 to 6 carbon atoms. The alkylene group may be either linear or branched. Examples of alkylene groups having 1 to 6 carbon atoms include methylene, ethylene, n-propylene, isopropylene, n-butylene, sec-butylene, pentylene, and hexylene. Among these, R 22 is preferably a methylene group, an ethylene group, or an n-propylene group.

[0077] In formula (d1-2), R 23 each independently represents a hydrogen atom or a methyl group.

[0078] In formula (d1-2), R 24 R each independently represents an alkyl group or an aralkyl group. 24 Examples of the alkyl group represented by R include a methyl group, an ethyl group, and a propyl group. 24 Examples of the aralkyl group represented by include a benzyl group and a phenethyl group.

[0079] In formula (d1-2), m represents an integer of 3 to 300, preferably an integer of 5 to 100, and more preferably an integer of 10 to 30.

[0080] In formula (d1-3), R 31 are each independently an alkyl group having 1 to 8 carbon atoms. The alkyl group may be either linear or branched. The alkyl group having 1 to 8 carbon atoms is as described above. Among them, R 31 is preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group.

[0081] In formula (d1-3), R 32 are each independently an alkylene group having 1 to 6 carbon atoms. The alkylene group may be either linear or branched. The alkylene group having 1 to 6 carbon atoms is as described above. Among them, R 32 is preferably a methylene group, an ethylene group, or an n-propylene group.

[0082] In formula (d1-3), R 33 and R 34 R each independently represents a divalent hydrocarbon group having 1 to 6 carbon atoms. 33 and R 34 may be a saturated or unsaturated hydrocarbon group. Examples of the divalent hydrocarbon group having 1 to 6 carbon atoms include alkylene groups such as methylene, ethylene, propylene, butylene, pentylene, and hexylene; alkenylene groups such as ethenylene, propenylene, butenylene, pentenylene, and hexenylene; alkynylene groups such as methylethynylene, pentynylene, and hexynylene; and phenylene groups.

[0083] In formula (d1-3), R 35 R each independently represents an alkyl group or an aralkyl group. 35 The alkyl group represented by R 24 The alkyl groups represented by R 35The aralkyl group represented by R 24 Examples of the aralkyl group include the same as the aralkyl group represented by the formula:

[0084] In formula (d1-3), n represents an integer of 3 to 300, preferably an integer of 5 to 100, and more preferably an integer of 10 to 30.

[0085] When the (D-1) polysiloxane compound has a polydialkylsiloxane structure represented by formula (d1-1) and a modified polydialkylsiloxane structure represented by formula (d1-2) or formula (d1-3), these structures may be a random copolymer, a block copolymer, or a graft polymer.

[0086] The polysiloxane compound (D-1) may be used alone or in combination of two or more.

[0087] Commercially available surface conditioners include, for example, "BYK-300," "BYK-301," "BYK-302," "BYK-306," "BYK-307," "BYK-320," "BYK-325," "BYK-331," "BYK-337," "BYK-333," and "BYK-341" manufactured by BYK Japan; "KF-351A," "KF-352A," and "KF-353" manufactured by Shin-Etsu Silicones Co., Ltd. (polyether-modified polydialkylsiloxanes (i.e., polysiloxane compounds having a modified polydialkylsiloxane structure represented by formula (d1-2))); "BYK-310," "BYK-314," and "BYK-315" manufactured by BYK Japan; and "X-22-715" manufactured by Shin-Etsu Silicones Co., Ltd. (polyester-modified polydialkylsiloxanes (i.e., polysiloxane compounds having a modified polydialkylsiloxane structure represented by formula (d1-3))).BYK-Chemie Japan's "BYK-313", "BYK-322", "BYK-323", "BYK-330", "BYK-344", "BYK-345", "BYK-346", "BYK-347", "BYK-348", "BYK-349", "BYK-370", "BYK-375", "BYK-377", "BYK-378", "BYK-UV3500", "BYK-UV3510", "BYK-UV3570", "BYK-3550", "BYK-SILCLEAN3700", "BYK-SILCLEAN3720", and Algin Chemie's "AC FS 180", "AC FS 360", and "AC S 20", Kyoeisha Chemical Co., Ltd.'s "Polyflow KL-400X", "Polyflow KL-400HF", "Polyflow KL-401", "Polyflow KL-402", "Polyflow KL-403", and "Polyflow KL-404", and Shin-Etsu Chemical Co., Ltd.'s "KP-124", "KP-109", "KP-121", "KP-103", "KP-341", "KP-112", "KP-125", "KP-101", and "KP-106". , "KP-120", "KP-105", "KP-104", "KP-611", "KP-626", "KP-327", "KP-323", "KP-322", "KP-310", "KP-109", "K P-620'', ``KP-652'', ``KP-306'', ``KP-301'', ``KP-621'', ``KP-369'', ``KP-368'', ``LP-7001'', ``LP-7002'', ``8032'' manufactured by Dow-Toray. ADDITIVE", "57 ADDITIVE", "L-7604", "FZ-2110", "FZ-2105", "67 ADDITIVE", "8618 ADDITIVE", "3 ADDITIVE", "56 ADDITIVE", and Kusumoto Chemicals' "Disparlon LS-430", "Disparlon LS-220", "Disparlon LS-240", "Disparlon LS-260", "Disparlon LS-280", and "Disparlon LS-480" (polysiloxane compounds) manufactured by Kusumoto Chemicals; and "Disparlon UVX-271", "Disparlon UVX-272", "Disparlon UVX-3750", "Disparlon UVX-35", and "Disparlon UVX-36" (poly(meth)acrylate compounds) manufactured by Kusumoto Chemicals;Kusumoto Chemicals' "Disparlon NSH-8430HF", "Disparlon LHP-810", "Disparlon NSF-8363", "Disparlon UVX-2280", and "Disparlon UVX-2285" (compounds having a polysiloxane structure and a poly(meth)acrylate structure); BYK-340 manufactured by BYK Japan, and "AC FS 110a" and "AC FS 110a" manufactured by Algin Chemie. 100a", DIC's "Megafac F-114", "Megafac F-410", "Megafac F-430", "Megafac F-444", "Megafac F-472SF", "Megafac F-477", "Megafac F-552", "Megafac F-553", "Megafac F-554", "Megafac F-555", "Megafac F-556", "Megafac F-558", "Megafac R-94", "Megafac RS-72-K", "Megafac RS-75", "Megafac EXP TF-1367", "Megafac EXP TF-1437", "Megafac EXP TF-1537", "Megafac EXP TP-2026", Sumitomo 3M's "FC-4430", "FC-4432", Neos's "Ftergent 100", "Ftergent 100C", "Ftergent 110", "Ftergent 150," "Ftergent 150CH," "Ftergent AK," "Ftergent 501," "Ftergent 250," "Ftergent 251," "Ftergent 222F," "Ftergent 208G," "Ftergent 300," "Ftergent 310," "Ftergent 400SW," and Kitamura Chemical Industries' "PF-136A," "PF-156A," "PF-151N," "PF-636," "PF-6320," "PF-656," "PF-6520," "PF-651," and "PF-652" (fluorine-containing compounds);

[0088] The content of component (D) in the ink is 0.15% by mass or more and 1% by mass or less, based on 100% by mass of all components in the ink excluding organic solvents. This content is preferably 0.17% by mass or more, more preferably 0.19% by mass or more, and even more preferably 0.21% by mass or more, and is preferably 0.9% by mass or less, more preferably 0.8% by mass or less, and even more preferably 0.7% by mass or less, 0.68% by mass or less, or 0.66% by mass or less. When the content of component (D) is within this range, the average coefficient of linear thermal expansion (CTE) of the cured ink can be reduced. Furthermore, when the content of component (D) is within this range, ink ejection defects and precipitation of inorganic fillers in the ink can be suppressed.

[0089] The content of component (D) in the ink is preferably 0.3% by mass or more, more preferably 0.5% by mass or more, even more preferably 0.6% by mass or more, 0.62% by mass or more, or 0.64% by mass or more, relative to 100% by mass of the resin components in the ink, and is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 2% by mass or less. When the content of component (D) is within the above range, ink ejection defects can be suppressed, and precipitation of inorganic fillers in the ink can be suppressed.

[0090] <(E) Hardener> The inkjet ink of the present invention may contain a (E) curing agent as an optional component. A curing agent refers to a resin that can react with an epoxy resin to form a bond. The (E) curing agent as component (E) does not include those that fall under the above-mentioned components (A) to (D). The (E) curing agent may be used alone or in combination of two or more types.

[0091] Examples of the (E) curing agent include active ester resins, phenolic resins, carbodiimide resins, amine resins, acid anhydride resins, benzoxazine resins, cyanate ester resins, thiol resins, etc. Among these, it is preferable that the (E) curing agent contains one or more curing agents selected from the group consisting of active ester resins, phenolic resins, and carbodiimide resins.

[0092] The active ester resin may be a compound having one or more, preferably two or more, active ester groups per molecule. Among these, preferred active ester resins are compounds having two or more highly reactive ester groups per molecule, such as phenol esters, thiophenol esters, N-hydroxyamine esters, and esters of heterocyclic hydroxy compounds. The active ester resin is preferably one obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. In particular, from the viewpoint of improving heat resistance, the active ester resin is preferably an active ester resin obtained from a carboxylic acid compound and a hydroxy compound, and more preferably an active ester resin obtained from a carboxylic acid compound and a phenol compound and / or a naphthol compound. Examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of phenol compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalene, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadiene-type diphenol compounds, and phenol novolak. Here, "dicyclopentadiene-type diphenol compounds" refers to diphenol compounds obtained by condensing one dicyclopentadiene molecule with two phenol molecules.

[0093] Preferred examples of the active ester resin include active ester resins containing a dicyclopentadiene-type diphenol structure, active ester resins containing a naphthalene structure, active ester resins containing an acetylated product of phenol novolac, and active ester resins containing a benzoylated product of phenol novolac. Among these, active ester resins containing a naphthalene structure and active ester resins containing a dicyclopentadiene-type diphenol structure are more preferred. The "dicyclopentadiene-type diphenol structure" refers to a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene.

[0094] Commercially available activated ester resins include activated ester resins containing a dicyclopentadiene-type diphenol structure, such as "EXB9451," "EXB9460," "EXB9460S," "HPC-8000-65T," "HPC-8000H-65TM," and "EXB-8000L-65TM" (manufactured by DIC Corporation); activated ester resins containing a naphthalene structure, such as "EXB-9416-70BK," "EXB-8150-65T," "EXB-8100L-65T," and "EXB-8150L-65T" (manufactured by DIC Corporation); and phenol novolac. Examples of active ester resins containing an acetylated product include "DC808" (manufactured by Mitsubishi Chemical Corporation); active ester resins containing a benzoylated product of phenol novolac include "YLH1026" (manufactured by Mitsubishi Chemical Corporation); active ester resins which are acetylated products of phenol novolac include "DC808" (manufactured by Mitsubishi Chemical Corporation); and active ester resins which are benzoylated products of phenol novolac include "YLH1026" (manufactured by Mitsubishi Chemical Corporation), "YLH1030" (manufactured by Mitsubishi Chemical Corporation), and "YLH1048" (manufactured by Mitsubishi Chemical Corporation).

[0095] As the phenolic resin, a resin having one or more, preferably two or more, hydroxyl groups bonded to an aromatic ring such as a benzene ring or a naphthalene ring per molecule can be used. From the viewpoint of heat resistance and water resistance, a phenolic resin having a novolac structure is preferred. From the viewpoint of adhesion, a nitrogen-containing phenolic resin is preferred, and a triazine skeleton-containing phenolic resin is more preferred. Among them, a triazine skeleton-containing phenolic novolac resin is preferred from the viewpoint of highly satisfying heat resistance, water resistance, and adhesion.

[0096] Specific examples of phenolic resins include "MEH-7700", "MEH-7810", "MEH-7851", and "MEH-8000H" manufactured by Meiwa Chemical Industry Co., Ltd.; "NHN", "CBN", and "GPH" manufactured by Nippon Kayaku Co., Ltd.; and "SN-170", "SN-180", "SN-190", "SN-475", "SN-485", "SN-495", "SN-495V", "SN-375", and "SN" manufactured by Nippon Steel Chemical & Material Co., Ltd. -395"; "TD-2090", "TD-2090-60M", "LA-7052", "LA-7054", "LA-1356", "LA-3018", "LA-3018-50P", "EXB-9500", "HPC-9500", "KA-1160", "KA-1163", and "KA-1165" manufactured by DIC Corporation; and "GDP-6115L", "GDP-6115H", and "ELPC75" manufactured by Gun-ei Chemical Co., Ltd.

[0097] As the carbodiimide resin, a resin having one or more, preferably two or more, carbodiimide structures in one molecule can be used. Specific examples of the carbodiimide resin include aliphatic biscarbodiimides such as tetramethylene-bis(t-butylcarbodiimide) and cyclohexanebis(methylene-t-butylcarbodiimide); aromatic biscarbodiimides such as phenylene-bis(xylylcarbodiimide); aliphatic polycarbodiimides such as polyhexamethylenecarbodiimide, polytrimethylhexamethylenecarbodiimide, polycyclohexylenecarbodiimide, poly(methylenebiscyclohexylenecarbodiimide), and poly(isophoronecarbodiimide); poly(phenylenecarbodiimide), poly(naphthalenecarbodiimide); Examples of polycarbodiimides include aromatic polycarbodiimides such as poly(methylenediphenylenecarbodiimide), poly(tolylenecarbodiimide), poly(methyldiisopropylphenylenecarbodiimide), poly(triethylphenylenecarbodiimide), poly(diethylphenylenecarbodiimide), poly(triisopropylphenylenecarbodiimide), poly(diisopropylphenylenecarbodiimide), poly(xylylenecarbodiimide), poly(tetramethylxylylenecarbodiimide), poly(methylenediphenylenecarbodiimide), and poly[methylenebis(methylphenylene)carbodiimide]. Commercially available carbodiimide resins include, for example, "Carbodilite V-02B," "Carbodilite V-03," "Carbodilite V-04K," "Carbodilite V-07," and "Carbodilite V-09" manufactured by Nisshinbo Chemical Inc.; and "Stavaxol P," "Stavaxol P400," and "Hykasil 510" manufactured by Lanxess AG.

[0098] The amine resin may be a resin having one or more, preferably two or more, amino groups in one molecule. Examples of the amine resin include aliphatic amines, polyether amines, alicyclic amines, and aromatic amines. Among these, aromatic amines are preferred. The amine resin is preferably a primary amine or a secondary amine, and more preferably a primary amine. Specific examples of the amine resin include 4,4'-methylenebis(2,6-dimethylaniline), diphenyldiaminosulfone, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfone, 3,3'-diaminodiphenylsulfone, m-phenylenediamine, m-xylylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, 2,2-bis(3-amino-4-hydroxybenzoyl) Examples of suitable amine resins include 4,4'-bis(4-aminophenyl)propane, 3,3-dimethyl-5,5-diethyl-4,4-diphenylmethanediamine, 2,2-bis(4-aminophenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)sulfone, and bis(4-(3-aminophenoxy)phenyl)sulfone. Commercially available amine resins may be used, such as "KAYABOND C-200S," "KAYABOND C-100," "KAYAHARD AA," "KAYAHARD AB," and "KAYAHARD AS" manufactured by Nippon Kayaku Co., Ltd., and "Epicure W" manufactured by Mitsubishi Chemical Corporation.

[0099] As the acid anhydride resin, a resin having one or more acid anhydride groups in one molecule can be used, and a resin having two or more acid anhydride groups in one molecule is preferred. Specific examples of the acid anhydride resin include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenyl succinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, and benzophenonetetracarboxylic dianhydride. Examples of suitable anhydrides include anhydrides, biphenyltetracarboxylic dianhydride, naphthalenetetracarboxylic dianhydride, oxydiphthalic dianhydride, 3,3'-4,4'-diphenylsulfonetetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-C]furan-1,3-dione, ethylene glycol bis(anhydrotrimellitate), and polymeric anhydrides such as styrene-maleic acid resins, which are copolymers of styrene and maleic acid. Commercially available acid anhydride resins include, for example, "HNA-100," "MH-700," "MTA-15," "DDSA," and "OSA" manufactured by New Japan Chemical Co., Ltd.; "YH-306" and "YH-307" manufactured by Mitsubishi Chemical Corporation; "HN-2200" and "HN-5500" manufactured by Resonac Corporation; and "EF-30," "EF-40," "EF-60," and "EF-80" manufactured by Cray Valley Chemical Industries, Ltd.

[0100] Specific examples of benzoxazine resins include "JBZ-OD100," "JBZ-OP100D," and "ODA-BOZ" manufactured by JFE Chemical Corporation; "Pd" and "Fa" manufactured by Shikoku Chemicals Corporation; and "HFB2006M" manufactured by Showa Polymer Co., Ltd.

[0101] Examples of cyanate ester resins include bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylidene diphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane), bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl)thioether, and bis(4-cyanatephenyl)ether; polyfunctional cyanate resins derived from phenol novolac, cresol novolac, etc.; and prepolymers in which these cyanate resins are partially triazine converted. Specific examples of cyanate ester resins include "PT30" and "PT60" (phenol novolac type multifunctional cyanate ester resins), "ULL-950S" (multifunctional cyanate ester resin), "BA230" and "BA230S75" (prepolymers in which part or all of bisphenol A dicyanate has been triazine converted to a trimer), all of which are manufactured by Lonza.

[0102] Examples of thiol resins include trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptobutyrate), and tris(3-mercaptopropyl)isocyanurate.

[0103] The active group equivalent of the (E) curing agent is preferably 50 g / eq to 3000 g / eq, more preferably 100 g / eq to 1000 g / eq, even more preferably 100 g / eq to 500 g / eq, and even more preferably 100 g / eq to 300 g / eq. The active group equivalent represents the mass of the (E) curing agent per equivalent of the active group. The active group of the (E) curing agent is an active hydroxyl group or the like, and varies depending on the type of curing agent.

[0104] When the number of epoxy groups in the (A) epoxy resin is taken as 1, the number of active groups in the (E) curing agent is preferably 0.01 or more, more preferably 0.1 or more, even more preferably 0.5 or more, and preferably 10 or less, more preferably 5 or less, and even more preferably 3 or less. The active groups in the (E) curing agent are as described above. The number of epoxy groups in the (A) epoxy resin is the total value for all epoxy resins obtained by dividing the mass of the components of each epoxy resin excluding the organic solvent by the epoxy equivalent. The number of active groups in the (E) curing agent is the total value for all curing agents obtained by dividing the mass of the components of each curing agent excluding the organic solvent by the active group equivalent.

[0105] When the inkjet ink of the present invention contains a (E) curing agent, the content of component (E) in the ink is preferably 5% by mass or more, more preferably 10% by mass or more, even more preferably 15% by mass or more or 17% by mass or more, based on 100% by mass of all components in the ink excluding organic solvents, and is preferably 30% by mass or less, more preferably 25% by mass or less, even more preferably 20% by mass or less.

[0106] When the inkjet ink of the present invention contains a (E) curing agent, the content of component (E) in the ink is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 50% by mass or more or 53% by mass or more, relative to 100% by mass of the resin components in the ink, and is preferably 70% by mass or less, more preferably 60% by mass or less, even more preferably 56% by mass or less.

[0107] <(F)Thermoplastic resin> The inkjet ink of the present invention may contain a thermoplastic resin (F) as an optional component. The thermoplastic resin (F) as component (F) does not include those corresponding to the above-mentioned components (A) to (E). The thermoplastic resin (F) can effectively improve the mechanical properties of the cured ink. The thermoplastic resin (F) may be used alone or in combination of two or more types.

[0108] Examples of thermoplastic resins include phenoxy resins, polyimide resins, polyvinyl acetal resins, polyolefin resins, polybutadiene resins, polyamideimide resins, polyetherimide resins, polysulfone resins, polyethersulfone resins, polyphenylene ether resins, polycarbonate resins, polyetheretherketone resins, and polyester resins.

[0109] Examples of phenoxy resins include phenoxy resins having one or more skeletons selected from the group consisting of bisphenol A, bisphenol F, bisphenol S, bisphenolacetophenone, novolac, biphenyl, fluorene, dicyclopentadiene, norbornene, naphthalene, anthracene, adamantane, terpene, and trimethylcyclohexane. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. Specific examples of phenoxy resins include "1256" and "4250" manufactured by Mitsubishi Chemical Corporation (both of which are phenoxy resins containing a bisphenol A skeleton); "YX8100" manufactured by Mitsubishi Chemical Corporation (phenoxy resin containing a bisphenol S skeleton); "YX6954" manufactured by Mitsubishi Chemical Corporation (phenoxy resin containing a bisphenol acetophenone skeleton); "FX280" and "FX293" manufactured by Nippon Steel Chemical & Material Co., Ltd.; "YL7500BH30," "YX6954BH30," "YX7553," "YX7553BH30," "YL7769BH30," "YL6794," "YL7213," "YL7290," "YL7482," and "YL7891BH30" manufactured by Mitsubishi Chemical Corporation; and the like.

[0110] Specific examples of polyimide resins include "SLK-6100" manufactured by Shin-Etsu Chemical Co., Ltd., and "Rikacoat SN20" and "Rikacoat PN20" manufactured by New Japan Chemical Co., Ltd. Specific examples of polyimide resins also include modified polyimides such as linear polyimides obtained by reacting bifunctional hydroxyl group-terminated polybutadiene, a diisocyanate compound, and a tetrabasic acid anhydride (polyimides described in JP-A No. 2006-37083), and polysiloxane skeleton-containing polyimides (polyimides described in JP-A Nos. 2002-12667 and 2000-319386).

[0111] Examples of polyvinyl acetal resins include polyvinyl formal resins and polyvinyl butyral resins, with polyvinyl butyral resins being preferred. Specific examples of polyvinyl acetal resins include S-LEC BH series, BX series (e.g., BX-5Z), KS series (e.g., KS-1), BL series, and BM series manufactured by Sekisui Chemical Co., Ltd.

[0112] Examples of polyolefin resins include ethylene copolymer resins such as low-density polyethylene, very low-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, and ethylene-methyl acrylate copolymer; and polyolefin polymers such as polypropylene and ethylene-propylene block copolymer.

[0113] Examples of polybutadiene resins include hydrogenated polybutadiene skeleton-containing resins, hydroxy group-containing polybutadiene resins, phenolic hydroxy group-containing polybutadiene resins, carboxy group-containing polybutadiene resins, acid anhydride group-containing polybutadiene resins, epoxy group-containing polybutadiene resins, isocyanate group-containing polybutadiene resins, urethane group-containing polybutadiene resins, and polyphenylene ether-polybutadiene resins.

[0114] Specific examples of polyamide-imide resins include "Vylomax HR11NN" and "Vylomax HR16NN" manufactured by Toyobo Co., Ltd. Specific examples of polyamide-imide resins also include modified polyamide-imides such as "KS9100" and "KS9300" (polysiloxane skeleton-containing polyamide-imides) manufactured by Hitachi Chemical Co., Ltd.

[0115] A specific example of the polyethersulfone resin is "PES5003P" manufactured by Sumitomo Chemical Co., Ltd.

[0116] Specific examples of polysulfone resins include polysulfones "P1700" and "P3500" manufactured by Solvay Advanced Polymers.

[0117] A specific example of the polyphenylene ether resin is "NORYL SA90" manufactured by SABIC, etc. A specific example of the polyetherimide resin is "Ultem" manufactured by GE, etc.

[0118] Examples of polycarbonate resins include hydroxyl group-containing carbonate resins, phenolic hydroxyl group-containing carbonate resins, carboxyl group-containing carbonate resins, acid anhydride group-containing carbonate resins, isocyanate group-containing carbonate resins, and urethane group-containing carbonate resins. Specific examples of polycarbonate resins include "FPC0220" manufactured by Mitsubishi Gas Chemical Company, Inc., "T6002" and "T6001" (polycarbonate diols) manufactured by Asahi Kasei Corporation, and "C-1090," "C-2090," and "C-3090" (polycarbonate diols) manufactured by Kuraray Co., Ltd. Specific examples of polyether ether ketone resins include "Sumiploy K" manufactured by Sumitomo Chemical Co., Ltd.

[0119] Examples of polyester resins include polyethylene terephthalate resin, polyethylene naphthalate resin, polybutylene terephthalate resin, polybutylene naphthalate resin, polytrimethylene terephthalate resin, polytrimethylene naphthalate resin, and polycyclohexane dimethyl terephthalate resin.

[0120] The weight average molecular weight (Mw) of the thermoplastic resin is preferably greater than 5,000, more preferably at least 8,000, even more preferably at least 10,000, and even more preferably at least 20,000. There is no particular upper limit, and it can be, for example, 1 million or less, 500,000 or less, or 100,000 or less. The weight average molecular weight of the thermoplastic resin can be measured as a polystyrene-equivalent value by gel permeation chromatography (GPC).

[0121] When the inkjet ink of the present invention contains a (F) thermoplastic resin, the content of component (F) in the ink is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, even more preferably 0.5% by mass or more or 0.6% by mass or more, based on 100% by mass of all components in the ink excluding organic solvents, and is preferably 5% by mass or less, more preferably 3% by mass or less, even more preferably 1% by mass or less or 0.7% by mass or less.

[0122] When the inkjet ink of the present invention contains a thermoplastic resin (F), the content of the component (F) in the ink is preferably 0.5% by mass or more, more preferably 1% by mass or more, even more preferably 1.5% by mass or more or 1.7% by mass or more, relative to 100% by mass of the resin components in the ink, and is preferably 10% by mass or less, more preferably 5% by mass or less, even more preferably 3% by mass or less or 2% by mass or less.

[0123] <(G) Curing accelerator> The inkjet ink of the present invention may contain a (G) curing accelerator as an optional component. The (G) curing accelerator as component (G) does not include those corresponding to the above-mentioned components (A) to (F). The (G) curing accelerator functions as a catalyst for the reaction of the (A) epoxy resin (and the (E) curing agent), and therefore can accelerate the curing of the ink. The (G) curing accelerator may be used alone or in combination of two or more types.

[0124] Examples of the curing accelerator include imidazole-based curing accelerators, phosphorus-based curing accelerators, amine-based curing accelerators, guanidine-based curing accelerators, metal-based curing accelerators, and urea-based curing accelerators.

[0125] Examples of the imidazole curing accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazolium trimellitate, 1-cyanoethyl-2-phenylimidazolium trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2, 4-Diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4,5-dihydroxymethylimidazole, Examples of the imidazole compound include imidazole compounds such as 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, and 2-phenylimidazoline, as well as adducts of imidazole compounds with epoxy resins, and 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole are preferred. As the imidazole-based curing accelerator, commercially available products may be used, such as "P200-H50" manufactured by Mitsubishi Chemical Corporation; and "Curezol 2MZ", "2E4MZ", "Cl1Z", "Cl1Z-CN", "Cl1Z-CNS", "Cl1Z-A", "2MZ-OK", "2MA-OK", "2MA-OK-PW", "2MZA-PW", "2PHZ", "2PHZ-PW", "1B2PZ", and "1B2PZ-10M" manufactured by Shikoku Chemicals Corporation.

[0126] Examples of the phosphorus-based curing accelerator include phosphonium salts and phosphines. Examples of the phosphonium salt include aliphatic phosphonium salts such as tetrabutylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium acetate, tetrabutylphosphonium decanoate, tetrabutylphosphonium laurate, n-butylphosphonium tetraphenylborate, bis(tetrabutylphosphonium)pyromellitate, tetrabutylphosphonium hydrogenhexahydrophthalate, tetrabutylphosphonium 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenolate, and di-tert-butylmethylphosphonium tetraphenylborate; methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, and propyltriphenylphosphonium. bromide, butyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, tetraphenylphosphonium bromide, p-tolyltriphenylphosphonium tetra-p-tolylborate, tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium tetra-p-tolylborate, triphenylethylphosphonium tetraphenylborate, tris(3-methylphenyl)ethylphosphonium tetraphenylborate, tris(2-methoxyphenyl)ethylphosphonium tetraphenylborate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, and aromatic phosphonium salts such as butyltriphenylphosphonium thiocyanate.

[0127] Examples of phosphines include aliphatic phosphines such as tributylphosphine, tri-tert-butylphosphine, trioctylphosphine, di-tert-butyl(2-butenyl)phosphine, di-tert-butyl(3-methyl-2-butenyl)phosphine, and tricyclohexylphosphine; dibutylphenylphosphine, di-tert-butylphenylphosphine, methyldiphenylphosphine, ethyldiphenylphosphine, butyldiphenylphosphine, diphenylcyclohexylphosphine, triphenylphosphine, tri-o-tolylphosphine, tri-m-tolylphosphine, tri-p-tolylphosphine, tris(4-ethylphenyl)phosphine, tris(4-propylphenyl)phosphine, tris(4-isopropylphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(4-tert-butylphenyl)phosphine, tris(2,4-dimethylphenyl)phosphine, and tris(2,5-dimethylphenyl)phosphine. tris(2,6-dimethylphenyl)phosphine, tris(3,5-dimethylphenyl)phosphine, tris(2,4,6-trimethylphenyl)phosphine, tris(2,6-dimethyl-4-ethoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(4-ethoxyphenyl)phosphine, tris(4-tert-butoxyphenyl)phosphine, diphenyl-2-pyridylphosphine, 1,2- Examples include aromatic phosphines such as bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,2-bis(diphenylphosphino)acetylene, and 2,2'-bis(diphenylphosphino)diphenyl ether; aromatic phosphine-borane complexes such as triphenylphosphine-triphenylborane; and aromatic phosphine-quinone adducts such as triphenylphosphine-p-benzoquinone adduct.

[0128] As the phosphorus-based curing accelerator, commercially available products may be used, for example, "TBP-DA" manufactured by Hokko Chemical Industry Co., Ltd.

[0129] Examples of the amine curing accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diazabicyclo(5,4,0)-undecene, 1,8-diazabicyclo[5,4,0]undecene-7,4-dimethylaminopyridine, and 2,4,6-tris(dimethylaminomethyl)phenol, with 4-dimethylaminopyridine being preferred. Commercially available amine curing accelerators may also be used, such as "PN-50," "PN-23," and "MY-25" manufactured by Ajinomoto Fine-Techno Co., Inc.

[0130] Examples of guanidine-based curing accelerators include dicyandiamide, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene. Examples of suitable biguanide include 1-methylbiguanide, 1-ethylbiguanide, 1-n-butylbiguanide, 1-n-octadecylbiguanide, 1,1-dimethylbiguanide, 1,1-diethylbiguanide, 1-cyclohexylbiguanide, 1-allylbiguanide, 1-phenylbiguanide, and 1-(o-tolyl)biguanide. Of these, dicyandiamide and 1,5,7-triazabicyclo[4.4.0]dec-5-ene are preferred.

[0131] Examples of metal-based curing accelerators include organometallic complexes or organometallic salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of organometallic complexes include organic cobalt complexes such as cobalt(II) acetylacetonate and cobalt(III) acetylacetonate, organic copper complexes such as copper(II) acetylacetonate, organic zinc complexes such as zinc(II) acetylacetonate, organic iron complexes such as iron(III) acetylacetonate, organic nickel complexes such as nickel(II) acetylacetonate, and organic manganese complexes such as manganese(II) acetylacetonate. Examples of organometallic salts include zinc octoate, tin octoate, zinc naphthenate, cobalt naphthenate, tin stearate, and zinc stearate.

[0132] Examples of the urea-based curing accelerator include 1,1-dimethylurea; aliphatic dimethylureas such as 1,1,3-trimethylurea, 3-ethyl-1,1-dimethylurea, 3-cyclohexyl-1,1-dimethylurea, and 3-cyclooctyl-1,1-dimethylurea; 3-phenyl-1,1-dimethylurea, 3-(4-chlorophenyl)-1,1-dimethylurea, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(3-chloro-4-methylphenyl)-1,1-dimethylurea, 3-(2-methylphenyl)-1,1-dimethylurea, 3-(4-methylphenyl)-1,1-dimethylurea, and 3-(3,4-dimethylphenyl)-1,1-dimethylurea. aromatic dimethylureas such as toluene bis(dimethylurea), 3-(4-isopropylphenyl)-1,1-dimethylurea, 3-(4-methoxyphenyl)-1,1-dimethylurea, 3-(4-nitrophenyl)-1,1-dimethylurea, 3-[4-(4-methoxyphenoxy)phenyl]-1,1-dimethylurea, 3-[4-(4-chlorophenoxy)phenyl]-1,1-dimethylurea, 3-[3-(trifluoromethyl)phenyl]-1,1-dimethylurea, N,N-(1,4-phenylene)bis(N',N'-dimethylurea), and N,N-(4-methyl-1,3-phenylene)bis(N',N'-dimethylurea) [toluene bisdimethylurea].

[0133] When the inkjet ink of the present invention contains a (G) curing accelerator, the content of component (G) in the ink is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, even more preferably 0.04% by mass or more, based on 100% by mass of all components in the ink excluding organic solvents, and is preferably 0.50% by mass or less, more preferably 0.10% by mass or less, even more preferably 0.05% by mass or less.

[0134] When the inkjet ink of the present invention contains a (G) curing accelerator, the content of the (G) component in the ink is preferably 0.01% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, relative to 100% by mass of the resin components in the ink, and is preferably 1% by mass or less, more preferably 0.5% by mass or less, even more preferably 0.3% by mass or less or 0.2% by mass or less.

[0135] <(H) Other Additives> The inkjet ink of the present invention may further contain (H) other additives as an optional component in combination with the above-mentioned components (A) to (G). The other additives (H) as component (H) do not include those that correspond to the above-mentioned components (A) to (G).

[0136] (H) Other additives include, for example, radical polymerizable compounds such as maleimide-based radical polymerizable compounds, vinylphenyl-based radical polymerizable compounds, (meth)acrylic-based radical polymerizable compounds, allyl-based radical polymerizable compounds, and polybutadiene-based radical polymerizable compounds; radical polymerization initiators such as peroxide-based radical polymerization initiators and azo-based radical polymerization initiators; organic fillers such as rubber particles; organometallic compounds such as organocopper compounds and organozinc compounds; colorants such as phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, and carbon black; polymerization inhibitors such as hydroquinone, catechol, pyrogallol, and phenothiazine; thickeners such as bentone and montmorillonite; and silicone extinguishers. Examples of the additives include antifoaming agents such as foaming agents, acrylic antifoaming agents, fluorine-based antifoaming agents, and vinyl resin antifoaming agents; ultraviolet absorbers such as benzotriazole-based ultraviolet absorbers; adhesion improvers such as urea silanes; adhesion promoters such as triazole-based adhesion promoters, tetrazole-based adhesion promoters, and triazine-based adhesion promoters; antioxidants such as hindered phenol-based antioxidants; flame retardants such as phosphorus-based flame retardants (e.g., phosphate ester compounds, phosphazene compounds, phosphinic acid compounds, and red phosphorus), nitrogen-based flame retardants (e.g., melamine sulfate), halogen-based flame retardants, and inorganic flame retardants (e.g., antimony trioxide); and stabilizers such as borate-based stabilizers, titanate-based stabilizers, aluminate-based stabilizers, zirconate-based stabilizers, isocyanate-based stabilizers, carboxylic acid-based stabilizers, and carboxylic anhydride-based stabilizers. (H) Other additives may be used alone or in combination of two or more.

[0137] [Inkjet ink manufacturing method] The inkjet ink of the present invention can be produced, for example, by mixing the above-mentioned components. The above-mentioned components may be mixed partially or entirely at the same time, or may be mixed sequentially. The temperature may be appropriately set during the process of mixing the components, and thus heating and / or cooling may be performed temporarily or throughout. Furthermore, stirring or shaking may be performed during the process of mixing the components. Furthermore, degassing may be performed under low-pressure conditions, such as under vacuum.

[0138] [Characteristics of inkjet ink] The inkjet ink of the present invention comprises (A) an epoxy resin, (B) an organic solvent, (C) an inorganic filler, and (D) a surface conditioner (and, if necessary, (E) a curing agent, (F) a thermoplastic resin, (G) a curing accelerator, and (H) other additives), wherein the component (B) comprises (B-1) an organic solvent having a boiling point of 135°C or more and 190°C or less, the content of the component (B) is 50% by mass or more and 60% by mass or less, based on 100% by mass of all components in the ink, the content of the component (D) is 0.15% by mass or more and 1% by mass or less, based on 100% by mass of all components in the ink excluding the organic solvent, and the content of the component (B-1) is 50% by mass or more, based on 100% by mass of the component (B). This results in a cured product with a small average coefficient of linear thermal expansion (CTE), which can prevent ejection defects and can prevent precipitation of the inorganic filler.

[0139] The cured product of the inkjet ink of the present invention has a small average coefficient of linear thermal expansion (CTE). For example, as described in the section <Test Example 4: Measurement of average coefficient of linear thermal expansion (CTE)> below, the average coefficient of linear thermal expansion of the cured product obtained by thermally curing the ink at 200°C for 90 minutes is preferably less than 30 ppm / K, more preferably 28 ppm / K or less. There is no particular restriction on the lower limit of the average coefficient of linear thermal expansion, and it can be, for example, 1 ppm / K or more.

[0140] The inkjet ink of the present invention can suppress ink ejection defects. For example, as described in the section <Test Example 3: Inkjet Ejection Test> below, it is possible to suppress ink bubble entrapment (the generation of minute air bubbles) when the ink is ejected. It is also possible to suppress ejection failure due to an increase in ink viscosity. It is also possible to suppress nozzle clogging due to dried ink.

[0141] The inkjet ink of the present invention can suppress the precipitation of inorganic fillers. For example, as described in Test Example 5: Ink Sedimentation Evaluation Test, when the ink was left to stand for three days at room temperature, in a refrigerator at 5°C, and in a freezer at -25°C, no precipitation of inorganic fillers occurred under any of the conditions.

[0142] The inkjet ink of the present invention may have a low viscosity. For example, as described in the section "Test Example 1: Viscosity Measurement," when measured for 2 minutes using an E-type viscometer under conditions of a measurement temperature of 25°C, a rotor of 1.34° x R24, an ink volume of 1.2 ml, and a rotation speed of 50 rpm, the viscosity of the ink is preferably 20 mPa·s or less, more preferably 15 mPa·s or less, and even more preferably 10 mPa·s or less. There is no particular lower limit to the viscosity of the ink, and it may be, for example, 0.1 mPa·s or more.

[0143] The inkjet ink of the present invention may have a surface tension suitable for the inkjet method. For example, as described in the section "Test Example 2: Measurement of Surface Tension," measurements are made five times using the pendant drop method at a measurement temperature of 25°C. When the average value of these five measurements is taken as the surface tension of the ink, the surface tension of the ink is preferably 20 mN / m or more, more preferably 23 mN / m or more, and even more preferably 25 mN / m or more, and is preferably 50 mN / m or less, more preferably 40 mN / m or less, and even more preferably 35 mN / m or less or 30 mN / m or less.

[0144] The cured product of the inkjet ink of the present invention may have a low dielectric dissipation factor. For example, when measured at 5.8 GHz and 23°C as described in <Test Example 6: Measurement of Dielectric Dissipation Factor (Df)>, the dielectric dissipation factor (Df) of the cured product obtained by thermally curing the ink at 200°C for 90 minutes is preferably 0.006 or less, more preferably 0.0055 or less, and even more preferably 0.005 or less. The lower limit of the dielectric dissipation factor may be 0.0001 or more.

[0145] [Inkjet ink applications] The inkjet ink of the present invention can be suitably used as an ink for forming an insulating layer of a printed wiring board (e.g., an ink for an insulating layer of a printed wiring board), and can be more suitably used as an ink for forming an interlayer insulating layer of a printed wiring board (e.g., an ink for an interlayer insulating layer of a printed wiring board). The inkjet ink of the present invention can also be suitably used when the printed wiring board is a circuit board with built-in components. The inkjet ink of the present invention can also be suitably used as an ink for forming an insulating layer of a rewiring board of a semiconductor package (e.g., an ink for an insulating layer of a rewiring board). In the present invention, printed wiring boards and rewiring boards are collectively referred to as "circuit boards," and therefore the inkjet ink of the present invention can be suitably used for forming an insulating layer of a circuit board.

[0146] The ink-jet ink of the present invention can also be used in a wide range of applications requiring ink, such as sheet-like laminate materials such as resin sheets, solder resists, underfill materials, die bonding materials, semiconductor encapsulants, hole-filling resins, and component-embedding resins.

[0147] [Resin sheet] The resin sheet of the present invention is a resin sheet comprising a support and a resin composition layer formed on the support, wherein the resin composition layer contains the inkjet ink described above.

[0148] In the resin sheet, the thickness of the resin composition layer varies depending on the application, and may be appropriately determined depending on the application. For example, from the viewpoint of thinning printed wiring boards and semiconductor packages, the thickness of the resin composition layer is preferably 100 μm or less, 80 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, or 30 μm or less. The lower limit of the thickness of the resin composition layer is not particularly limited, but may be, for example, 1 μm or more, 5 μm or more, etc.

[0149] In the resin sheet, examples of the support include a thermoplastic resin film, a metal foil, and a release paper, and a thermoplastic resin film and a metal foil are preferred. Therefore, in a preferred embodiment, the support is a thermoplastic resin film or a metal foil.

[0150] When a thermoplastic resin film is used as the support, examples of the thermoplastic resin include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), acrylics such as polycarbonate (PC) and polymethyl methacrylate (PMMA), cyclic polyolefins, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide, etc. Among these, polyethylene terephthalate and polyethylene naphthalate are preferred, and inexpensive polyethylene terephthalate is more preferred.

[0151] When a metal foil is used as the support, examples of the metal foil include copper foil and aluminum foil, with copper foil being preferred. The copper foil may be a foil made of a single metal, copper, or an alloy of copper and another metal (e.g., tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.).

[0152] The surface of the support to be bonded to the resin composition layer may be subjected to a matte treatment, a corona treatment, or an antistatic treatment. Alternatively, the support may be a support with a release layer, which has a release layer on the surface to be bonded to the resin composition layer. Examples of the release agent used in the release layer of the support with a release layer include one or more release agents selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins. Commercially available release agents include alkyd resin-based release agents such as "SK-1," "AL-5," and "AL-7" manufactured by Lintec Corporation. Commercially available release layer-containing supports include PET films having a release layer primarily composed of an alkyd resin-based release agent, such as "SK-1," "AL-5," and "AL-7" manufactured by Lintec Corporation; "Lumirror T60" manufactured by Toray Industries, Inc.; "Purex" manufactured by Teijin Limited; and "Uni-Peel" manufactured by Unitika Limited.

[0153] The thickness of the support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, more preferably 10 μm to 60 μm. When a support with a release layer is used, it is preferable that the thickness of the entire support with a release layer is in the above range.

[0154] When a metal foil is used as the support, a metal foil with a support substrate may be used, which is a thin metal foil with a peelable support substrate attached thereto. In one embodiment, the metal foil with a support substrate includes a support substrate, a release layer provided on the support substrate, and a metal foil provided on the release layer. When a metal foil with a support substrate is used as the support, the resin composition layer is provided on the metal foil.

[0155] In the metal foil with a supporting substrate, the material of the supporting substrate is not particularly limited, but examples thereof include copper foil, aluminum foil, stainless steel foil, titanium foil, copper alloy foil, etc. When copper foil is used as the supporting substrate, it may be electrolytic copper foil or rolled copper foil. Furthermore, the release layer is not particularly limited as long as it allows the metal foil to be released from the supporting substrate, and examples thereof include an alloy layer of an element selected from the group consisting of Cr, Ni, Co, Fe, Mo, Ti, W, and P; an organic coating, etc.

[0156] In the metal foil with a supporting substrate, the material of the metal foil is preferably, for example, copper foil or copper alloy foil.

[0157] In the metal foil with a supporting substrate, the thickness of the supporting substrate is not particularly limited, but is preferably in the range of 10 μm to 150 μm, more preferably in the range of 10 μm to 100 μm. The thickness of the metal foil may be, for example, in the range of 0.1 μm to 10 μm.

[0158] In one embodiment, the resin sheet may further include an optional layer, if necessary. Examples of such optional layers include a protective film provided on the surface of the resin composition layer that is not bonded to the support (i.e., the surface opposite the support). The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, adhesion of dust and the like to the surface of the resin composition layer and scratches can be suppressed.

[0159] The resin sheet can be produced, for example, by applying the inkjet ink described above onto a support by an inkjet method, and then drying the ink to form a resin composition layer.

[0160] The ink ejection method using the inkjet method may be a piezoelectric method using a piezoelectric element, or a thermal method using a heating element.

[0161] Drying may be carried out by known methods such as heating or hot air blowing. Drying conditions are not particularly limited, but drying is carried out so that the content of the organic solvent in the resin composition layer becomes 10% by mass or less, preferably 5% by mass or less. The formation of the resin composition layer varies depending on the boiling point of the organic solvent in the ink, but the resin composition layer can be formed, for example, by drying the ink at 80°C to 140°C for 1 minute to 10 minutes.

[0162] The resin sheet can be stored by being wound up in a roll. When the resin sheet has a protective film, the resin sheet can be used by peeling off the protective film.

[0163] [Circuit board and its manufacturing method] The ink-jet ink of the present invention can be used to form an insulating layer for a circuit board. The present invention also provides such a circuit board, i.e., a circuit board including an insulating layer made of a cured product obtained by curing the ink-jet ink described above. The insulating layer for the circuit board may be formed using the ink-jet ink described above, or may be formed using the resin sheet described above.

[0164] <Method of manufacturing a circuit board according to the first example> The circuit board according to the first example is manufactured using the ink-jet ink described above. The circuit board according to the first example can be manufactured, for example, by a method including the following steps (i) to (iii): (i) A step of applying an inkjet ink onto a substrate by an inkjet method. (ii) A step of forming a resin composition layer by drying the inkjet ink (iii) A step of forming an insulating layer by curing the resin composition layer.

[0165] In step (i), an inkjet ink is applied onto a substrate by an inkjet method.

[0166] The ink ejection method using the inkjet method may be a piezoelectric method or a thermal method.

[0167] The "substrate" used in step (i) refers to a member that serves as the substrate of a circuit board, and examples thereof include glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, and thermosetting polyphenylene ether substrates. The substrate may have a conductor layer on one or both sides. The conductor layer provided on the substrate may be patterned. A substrate having a conductor layer (circuit) formed on one or both sides is sometimes called an "inner layer circuit substrate." In addition, the term "substrate" also includes intermediate products on which an insulating layer and / or a conductor layer is to be further formed when manufacturing a circuit board. When the circuit board is a circuit board with built-in components, an inner layer substrate with built-in components may be used.

[0168] The thickness of the resin composition layer formed in step (i) is preferably 100 μm or less, 80 μm or less, 60 μm or less, 50 μm or less, 40 μm or less, or 30 μm or less, from the viewpoint of thinning the circuit board. The lower limit of the thickness of the resin composition layer is not particularly limited, but may be, for example, 1 μm or more, 5 μm or more, etc.

[0169] In step (i), the inkjet ink may be (i-1) applied (solid coating) to the entire surface of the substrate, (i-2) if the substrate has recesses such as vias or trenches, it may be selectively applied to the recesses on the substrate, or (i-3) selectively applied to areas other than the wiring pattern formation area so that the main surface of the substrate is exposed in the desired wiring pattern.

[0170] When the inkjet printing ink is applied to a substrate in a solid state as in (i-1) above, an insulating layer is formed over the entire surface of the substrate through steps (ii) and (iii) described below. In this case, the wiring pattern may be produced by a conventional process such as a semi-additive method (see steps (X) to (Z) described below).

[0171] When the inkjet ink is selectively applied to recesses on a substrate as in (i-2) above, an insulating layer is formed to fill the recesses on the substrate through the steps (ii) and (iii) described below. For example, if the substrate has via holes, after providing a plated conductor for electrical connection between layers, the inkjet ink may be applied to the recesses (via cavities) to form an insulating layer to fill the recesses. This makes it possible to form an insulating layer in the desired location without using a separate mask pattern, etc.

[0172] When the inkjet ink is selectively applied to areas other than the wiring pattern formation area as in (i-3) above, an insulating layer is formed in a predetermined pattern through the steps (ii) and (iii) described below so that the main surface of the substrate is exposed in the desired wiring pattern. In this case, by providing a conductor layer in the exposed area of ​​the main surface of the substrate, the desired wiring pattern can be formed without using a separate plating resist, as in conventional methods. For example, when an inner layer circuit substrate is used as the substrate, the exposed conductor layer (circuit) of the inner layer circuit substrate can be used as a plating electrode to form the conductor layer by electrolytic plating (in an embodiment in which the main surface of the substrate is exposed in the form of a via hole, the step (X) described below is not necessary).

[0173] In step (ii), the ink is applied to a substrate and then dried to form a resin composition layer. The ink drying conditions are not particularly limited, and conditions typically employed in forming an insulating layer for a circuit board may be used.

[0174] In step (ii), the content of the organic solvent in the resin composition layer formed is preferably 10% by mass or less, and more preferably 5% by mass or less, relative to 100% by mass of all components of the resin composition layer.

[0175] The ink can be dried in step (ii) by, for example, vacuuming, reducing pressure, heating, blowing hot air, or a combination of these. Among these, drying by vacuuming, reducing pressure, and / or heating is preferred.

[0176] In step (ii), when drying is performed by vacuum and / or reduced pressure, the air pressure is preferably 500 Pa or less, more preferably 200 Pa or less. The vacuum drying time is not particularly limited, but is preferably 30 seconds to 30 minutes, more preferably 30 seconds to 10 minutes.

[0177] In step (ii), when drying is performed by heating, the heating and drying temperature is preferably 50° C. or higher, more preferably 70° C. or higher, and even more preferably 80° C. or higher, and is preferably less than 200° C., more preferably less than 150° C., and even more preferably less than 140° C., less than 130° C., or less than 120° C. The heating and drying time during which the temperature is maintained is preferably 1 to 30 minutes, more preferably 1 to 10 minutes, and even more preferably 1 to 5 minutes.

[0178] In a preferred embodiment, step (ii) comprises drying by vacuum and / or reduced pressure, followed by further drying by heating.

[0179] Step (iii) is a step of thermally curing the resin composition layer to form an insulating layer. The thermal curing conditions for the resin composition layer are not particularly limited, and conditions typically employed for forming insulating layers for circuit boards may be used.

[0180] <Method of manufacturing a circuit board according to a second example> The circuit board according to the second example is manufactured using the resin sheet described above. The circuit board according to the second example can be manufactured, for example, by a method including the following steps (I) and (II). (I) A step of laminating a resin sheet on a substrate so that the resin composition layer of the resin sheet is bonded to the inner layer substrate. (II) Step of curing the resin composition layer to form an insulating layer

[0181] The "substrate" used in step (I) may be the same as that explained in step (i) of the <First example of the method for producing a circuit board>.

[0182] In step (I), the resin sheet can be laminated by, for example, thermocompression bonding the resin sheet to the substrate from the support side. Examples of a member for thermocompression bonding the resin sheet to the substrate (hereinafter also referred to as a "thermocompression bonding member") include a heated metal plate (such as a SUS end plate) or a metal roll (such as a SUS roll). The thermocompression bonding member may be pressed directly onto the resin sheet, or may be pressed via an elastic material such as heat-resistant rubber so that the resin sheet can sufficiently conform to the surface irregularities of the substrate.

[0183] The substrate and the resin sheet may be laminated by a vacuum lamination method. In the vacuum lamination method, the thermocompression temperature is preferably in the range of 60°C to 160°C, more preferably 80°C to 140°C, the thermocompression pressure is preferably in the range of 0.098MPa to 1.77MPa, more preferably 0.29MPa to 1.47MPa, and the thermocompression time is preferably in the range of 20 seconds to 400 seconds, more preferably 30 seconds to 300 seconds. The lamination may be carried out under reduced pressure conditions, preferably at a pressure of 26.7 hPa or less.

[0184] The lamination can be performed using a commercially available vacuum laminator, such as a vacuum pressure laminator manufactured by Meiki Seisakusho Co., Ltd., a vacuum applicator manufactured by Nikko Materials Co., Ltd., or a batch vacuum pressure laminator.

[0185] After lamination, the laminated resin sheets may be smoothed under normal pressure (atmospheric pressure), for example, by pressing a thermocompression member from the support side. The pressing conditions for the smoothing treatment may be the same as the thermocompression conditions for lamination. The smoothing treatment may be performed using a commercially available laminator. Note that lamination and smoothing treatment may be performed consecutively using the commercially available vacuum laminator.

[0186] The support may be removed between step (I) and step (II), or after step (II). When a metal foil is used as the support, the conductor layer may be formed using the metal foil without peeling off the support. When a metal foil with a supporting substrate is used as the support, the supporting substrate (and the release layer) may be peeled off. Then, the conductor layer can be formed using the metal foil.

[0187] In step (II), the resin composition layer is cured (for example, by heat curing) to form an insulating layer made of the cured product of the ink. The curing conditions for the resin composition layer are not particularly limited, and conditions typically employed for forming insulating layers for circuit boards may be used.

[0188] For example, the thermal curing conditions for the resin composition layer vary depending on the composition of the resin composition layer, but in one embodiment, the curing temperature is preferably 140° C. to 250° C., more preferably 150° C. to 240° C., and even more preferably 160° C. to 230° C. The curing time is preferably 5 minutes to 240 minutes, more preferably 10 minutes to 150 minutes, and even more preferably 15 minutes to 120 minutes.

[0189] Before thermally curing the resin composition layer, the resin composition layer may be preheated at a temperature lower than the curing temperature. For example, prior to thermally curing the resin composition layer, the resin composition layer may be preheated at a temperature of 50°C to 140°C, preferably 60°C to 135°C, more preferably 70°C to 130°C for 5 minutes or more, preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes, and even more preferably 15 minutes to 100 minutes.

[0190] <Optional Steps in the Circuit Board Manufacturing Methods According to the First and Second Examples> When manufacturing the circuit boards according to the first and second examples, the steps of (X) drilling holes in the insulating layer, (Y) roughening the insulating layer, and (Z) forming a conductor layer may be further carried out. These steps (X) to (Z) may be carried out according to various methods known to those skilled in the art that are used in manufacturing circuit boards. Furthermore, if necessary, the formation of insulating layers and conductor layers may be repeated to form a multilayer wiring board.

[0191] In the second method for producing a circuit board, when the support is removed after step (II), the removal of the support may be carried out between step (II) and step (X), between step (X) and step (Y), or between step (Y) and step (Z).

[0192] Step (X) is a step of drilling holes in the insulating layer, and this step can also form holes such as via holes and through holes in the insulating layer. Step (X) may be performed using, for example, a drill, a laser, plasma, or the like, depending on the composition of the ink used to form the insulating layer. The dimensions and shape of the holes may be determined appropriately depending on the design of the circuit board.

[0193] Step (Y) is a step of roughening the insulating layer. Usually, in step (Y), smear removal (desmearing) is also performed. The procedure and conditions for the roughening treatment are not particularly limited, and known procedures and conditions commonly used in forming insulating layers for printed wiring boards can be adopted. For example, the insulating layer can be roughened by performing a swelling treatment with a swelling liquid, a roughening treatment with an oxidizing agent, and a neutralization treatment with a neutralizing liquid in this order.

[0194] The swelling liquid used in the roughening treatment is not particularly limited, but examples thereof include alkaline solutions and surfactant solutions, and is preferably an alkaline solution, with sodium hydroxide solution and potassium hydroxide solution being more preferred. Commercially available swelling liquids include "Swelling Dip Securigance P" and "Swelling Dip Securigance SBU" manufactured by Atotech Japan. The swelling treatment using a swelling liquid is not particularly limited, but can be carried out by, for example, immersing the insulating layer in a swelling liquid at 30°C to 90°C for 1 to 20 minutes. From the viewpoint of suppressing swelling of the resin in the insulating layer to an appropriate level, it is preferable to immerse the insulating layer in a swelling liquid at 40°C to 80°C for 5 to 15 minutes.

[0195] The oxidizing agent used in the roughening treatment is not particularly limited, but examples include alkaline permanganate solutions prepared by dissolving potassium permanganate or sodium permanganate in an aqueous solution of sodium hydroxide. Roughening treatment using an oxidizing agent such as alkaline permanganate solution is preferably carried out by immersing the insulating layer in an oxidizing agent solution heated to 60°C to 100°C for 10 to 30 minutes. The concentration of permanganate in the alkaline permanganate solution is preferably 5% by mass to 10% by mass. Commercially available oxidizing agents include alkaline permanganate solutions such as "Concentrate Compact CP," "Concentrate Compact P," and "Dosing Solution Securigance P" manufactured by Atotech Japan.

[0196] The neutralizing solution used in the roughening treatment is preferably an acidic aqueous solution, and examples of commercially available products include "Reduction Solution Securigant P" manufactured by Atotech Japan.

[0197] Treatment with a neutralizing solution can be carried out by immersing the surface that has been roughened with an oxidizing agent in a neutralizing solution at 30° C. to 80° C. for 5 to 30 minutes. From the standpoint of workability, etc., a method in which the object that has been roughened with an oxidizing agent is immersed in a neutralizing solution at 40° C. to 70° C. for 5 to 20 minutes is preferred.

[0198] Step (Z) is a step of forming a conductor layer on an insulating layer. For example, in the method for manufacturing a circuit board according to the first example described above, if an insulating layer is selectively formed in a location other than the wiring pattern formation area as in step (i-3) in step (i), a desired wiring pattern can be formed by forming a conductor layer in the recess defined by the formed insulating layer. The conductor material used for the conductor layer is not particularly limited. In a preferred embodiment, the conductor layer contains one or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin, and indium. The conductor layer may be a single metal layer or an alloy layer. Examples of alloy layers include layers formed from alloys of two or more metals selected from the above group (e.g., nickel-chromium alloys, copper-nickel alloys, and copper-titanium alloys). Among these, from the viewpoints of versatility in forming the conductor layer, cost, ease of patterning, etc., a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or an alloy layer of a nickel-chromium alloy, a copper-nickel alloy, or a copper-titanium alloy is preferred, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver, or copper, or an alloy layer of a nickel-chromium alloy is more preferred, and a single metal layer of copper is even more preferred.

[0199] The conductor layer may have a single layer structure or a multi-layer structure in which two or more single metal layers or alloy layers made of different types of metals or alloys are laminated. When the conductor layer has a multi-layer structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc, or titanium, or an alloy layer of a nickel-chromium alloy.

[0200] The thickness of the conductor layer depends on the desired design of the printed wiring board, but is generally 3 μm to 35 μm, preferably 5 μm to 30 μm.

[0201] In one embodiment, the conductor layer may be formed by plating. From the viewpoint of facilitating the formation of fine wiring, it is preferable to form the conductor layer by a semi-additive method. An example of forming the conductor layer by a semi-additive method will be described below.

[0202] First, a plating seed layer is formed on the surface of an insulating layer by electroless plating. Next, a mask pattern is formed on the formed plating seed layer, exposing a portion of the plating seed layer corresponding to the desired wiring pattern. After a metal layer is formed on the exposed plating seed layer by electrolytic plating, the mask pattern is removed. Thereafter, unnecessary plating seed layer is removed by etching or the like, thereby forming a conductor layer having the desired wiring pattern.

[0203] In another embodiment, the conductor layer may be formed using a metal foil. When a metal foil is used to form the conductor layer, in the second method for producing a circuit board, it is preferable that step (Z) is performed between steps (I) and (II). For example, after step (I), the support is removed, and a metal foil is laminated on the exposed surface of the resin composition layer. The lamination of the resin composition layer and the metal foil may be performed by a vacuum lamination method. The lamination conditions may be the same as those described for step (I). Next, step (II) is performed to form an insulating layer. Thereafter, a conductor layer having a desired wiring pattern can be formed using the metal foil on the insulating layer by a conventional known technique such as a modified semi-additive method.

[0204] The metal foil can be produced by a known method such as an electrolytic method, a rolling method, etc. Examples of commercially available metal foils include HLP foil and JXUT-III foil manufactured by JX Nippon Mining & Smelting Co., Ltd., and 3EC-III foil and TP-III foil manufactured by Mitsui Mining & Smelting Co., Ltd.

[0205] Alternatively, when a metal foil or a metal foil with a supporting substrate is used as the support for the resin sheet, the conductor layer may be formed using the metal foil, as described above.

[0206] <Method of manufacturing a circuit board (rewiring board for semiconductor package) according to a third example> In the embodiment, the circuit board of the present invention is a rewiring board for a semiconductor package. Hereinafter, a method for manufacturing a semiconductor package will be described.

[0207] The semiconductor package contains a cured product of the inkjet ink of the present invention as an insulating layer of a rewiring substrate. The semiconductor package may also contain a cured product of the inkjet ink of the present invention as a sealing layer.

[0208] A semiconductor package can be manufactured, for example, by a method including the following steps (1) to (6) using the inkjet ink or resin sheet of the present invention. The inkjet ink or resin sheet of the present invention can be used to form a rewiring formation layer (specifically, an insulating layer for forming a rewiring substrate) in step (5) or a sealing layer in step (3). An example of forming a sealing layer and a rewiring formation layer using an inkjet ink and a resin sheet will be described below. However, techniques for forming sealing layers and rewiring formation layers for semiconductor packages are known, and a person skilled in the art can manufacture a semiconductor package using the inkjet ink and resin sheet of the present invention according to known techniques. (1) a step of laminating a temporary fixing film on a substrate; (2) a step of temporarily fixing a semiconductor chip on a temporary fixing film; (3) forming an encapsulation layer on the semiconductor chip; (4) peeling the substrate and the temporary fixing film from the semiconductor chip; (5) forming a rewiring formation layer as an insulating layer on the surface of the semiconductor chip from which the base material and the temporary fixing film have been peeled off; and (6) A step of forming a rewiring layer as a conductor layer on the rewiring formation layer.

[0209] -Process (1)- The "substrate" used in step (1) may be the same as that explained in step (i) of the <First example of the method for manufacturing a circuit board>.

[0210] The material of the temporary fixing film is not particularly limited as long as it can be peeled off from the semiconductor chip in step (4) and can temporarily fix the semiconductor chip. Commercially available products can be used as the temporary fixing film. Examples of commercially available products include Riva Alpha manufactured by Nitto Denko Corporation.

[0211] -Process (2)- The semiconductor chips can be temporarily fixed using known devices such as a flip chip bonder, a die bonder, etc. The layout and number of semiconductor chips to be arranged can be appropriately set depending on the shape and size of the temporary fixing film, the number of semiconductor packages to be produced, etc., and for example, the semiconductor chips can be temporarily fixed by arranging them in a matrix of multiple rows and multiple columns.

[0212] -Process (3)- A resin composition layer of the resin sheet of the present invention is laminated on a semiconductor chip, or the inkjet ink of the present invention is applied to a semiconductor chip by an inkjet method and cured (for example, thermally cured) to form a sealing layer.

[0213] For example, lamination of a semiconductor chip and a resin sheet can be performed by removing the protective film from the resin sheet and then thermocompressing the resin sheet to the semiconductor chip from the support side. Examples of a member for thermocompressing the resin sheet to the semiconductor chip (hereinafter also referred to as a "thermocompression member") include a heated metal plate (such as a SUS plate) or a metal roll (SUS roll). It is preferable to press the thermocompression member not directly onto the resin sheet, but via an elastic material such as heat-resistant rubber, so that the resin sheet can adequately conform to the surface irregularities of the semiconductor chip. The semiconductor chip and resin sheet can also be laminated by a vacuum lamination method, and the lamination conditions and preferred ranges are the same as those described in relation to the method for manufacturing a printed wiring board.

[0214] After lamination, the resin composition is thermally cured to form the sealing layer under the same conditions as those described in relation to the method for producing a printed wiring board.

[0215] The support of the resin sheet may be peeled off after the resin sheet is laminated on the semiconductor chip and thermally cured, or the support may be peeled off before the resin sheet is laminated on the semiconductor chip.

[0216] When the sealing layer is formed by applying the inkjet ink of the present invention, the ink may be ejected by a piezo method or a thermal method.

[0217] -Process (4)- The method for peeling off the substrate and the temporary fixing film can be changed as appropriate depending on the material of the temporary fixing film, etc., and examples include a method in which the temporary fixing film is heated and foamed (or expanded) to peel it off, and a method in which ultraviolet light is irradiated from the substrate side to reduce the adhesive strength of the temporary fixing film and peel it off.

[0218] In the method of heating and foaming (or expanding) the temporary fixing film to peel it off, the heating conditions are usually 100 to 250°C for 1 to 90 seconds or 5 to 15 minutes. In the method of irradiating ultraviolet light from the substrate side to reduce the adhesive strength of the temporary fixing film to peel it off, the irradiation dose of ultraviolet light is usually 10 mJ / cm. 2 ~1000mJ / cm 2 is.

[0219] -Process (5)- The ink-jet ink and resin sheet of the present invention are used to form a rewiring formation layer (insulating layer of a rewiring substrate).

[0220] After forming the redistribution layer, via holes may be formed in the redistribution layer to connect the semiconductor chip to a conductor layer (described later). The via holes may be formed by a known method depending on the material of the redistribution layer.

[0221] -Process (6)- The formation of the conductor layer on the rewiring formation layer may be carried out in the same manner as in step (Z) described in relation to the manufacturing method of the circuit board. Note that steps (5) and (6) may be repeated to alternately stack (build up) the conductor layer (rewiring layer) and the rewiring formation layer (insulating layer).

[0222] The manufacturing of the semiconductor package may further include steps of (7) forming a solder resist layer on the conductor layer (rewiring layer), (8) forming bumps, and (9) dicing the multiple semiconductor packages into individual semiconductor packages. These steps may be performed according to various methods known to those skilled in the art that are used in the manufacturing of semiconductor packages.

[0223] The semiconductor chip package manufactured by the above-described manufacturing method may be a fan-in type package or a fan-out type package. The inkjet ink and resin sheet of the present invention can be applied to both a fan-out panel level package (FOPLP) and a fan-out wafer level package (FOWLP). In one embodiment, the semiconductor chip package is a fan-out panel level package (FOPLP) or a fan-out wafer level package (FOWLP).

[0224] [Semiconductor Devices] The semiconductor device of the present invention includes a layer made of a cured product of the ink-jet ink of the present invention. The semiconductor device of the present invention can be manufactured using the circuit board of the present invention.

[0225] Examples of semiconductor devices include various semiconductor devices used in electrical appliances (for example, computers, mobile phones, digital cameras, and televisions) and vehicles (for example, motorcycles, automobiles, trains, ships, and aircraft). [Example]

[0226] The present invention will be specifically described below with reference to examples. However, the present invention is not limited to these examples. In the following description, "parts" and "%" representing amounts mean "parts by mass" and "% by mass", respectively, unless otherwise specified. Furthermore, the temperature and pressure conditions were room temperature (25°C) and atmospheric pressure (1 atm), unless otherwise specified.

[0227] Example 1: Preparation of Ink 1 30 parts of biphenyl epoxy resin (Nippon Kayaku Co., Ltd. "NC-3000-L", epoxy equivalent: approximately 271 g / eq.), 25 parts by mass of bixylenol epoxy resin (Mitsubishi Chemical Corporation "YX4000HK", epoxy equivalent: 190 g / eq.), 10 parts by mass of bisphenol epoxy resin (Nippon Steel Chemical & Material Co., Ltd. "ZX1059", 1:1 mixture of bisphenol A type and bisphenol F type, epoxy equivalent: 169 g / eq.), surface conditioner (Bikke 1.92 parts of "BYK-300" manufactured by Mie Corporation, a polyether-modified polymethylalkylsiloxane, the components excluding organic solvents are 52% by mass, xylene:ethylbenzene:isobutanol=20:20:7.5 solution), 100 parts of activated ester resin ("HPC-8000-65T" manufactured by DIC Corporation, the components excluding organic solvents are 65% by mass, toluene solution), 100 parts of carbodiimide resin ("Carbodilite V-03" manufactured by Nisshinbo Chemical Inc., the components excluding organic solvents are 50% by mass). 20 parts of triazine skeleton-containing phenolic resin (DIC Corporation's "LA-3018-50P," components excluding organic solvents are 50% by mass, propylene glycol monomethyl ether (PGM) solution, hydroxyl group equivalent: approximately 151 g / eq.), 20 parts of phenoxy resin (Mitsubishi Chemical Corporation's "YX7553BH30," components excluding organic solvents are 30% by mass, cyclohexanone (Anone):methyl ethyl ketone (MEK) = 1:1 solution) A mixture of 10 parts of methyl ethyl ketone (MEK) (Junsei Chemical Co., Ltd., boiling point 79°C), 0.2 parts of 4-dimethylaminopyridine (DMAP, manufactured by Tokyo Chemical Industry Co., Ltd.), 26.5 parts of methyl ethyl ketone (MEK) (Junsei Chemical Co., Ltd., boiling point 79°C), 25 parts of toluene (Junsei Chemical Co., Ltd., boiling point 110°C), 21.5 parts of cyclohexanone (Anone) (Junsei Chemical Co., Ltd., boiling point 155°C), and 420 parts of propylene glycol monomethyl ether acetate (PGMEA) (Kanto Chemical Co., Ltd., boiling point 146°C) was mixed and stirred at room temperature until a homogeneous solution was obtained. To the mixture was added 300 parts of a solid inorganic filler (Denka "UFP-30", average particle size: 0.3 μm) surface-treated with the aminosilane coupling agent "KBM573," and the mixture was uniformly dispersed using a high-pressure disperser to obtain Ink 1.

[0228] Example 2: Preparation of Ink 2 In Example 1, 1) The amount of propylene glycol monomethyl ether acetate (PGMEA) was changed from 420 parts to 300 parts. 2) Furthermore, 120 parts of N-methylpyrrolidone (NMP) was added. Ink 2 was obtained in the same manner as in Example 1 except for the above.

[0229] Example 3: Preparation of Ink 3 In Example 1, 1) The amount of propylene glycol monomethyl ether acetate (PGMEA) was changed from 420 parts to 300 parts. 2) The amount of methyl ethyl ketone (MEK) was changed from 26.5 parts to 146.5 parts. Ink 3 was obtained in the same manner as in Example 1 except for the above.

[0230] Example 4: Preparation of Ink 4 In Example 1, the amount of the surface conditioner (BYK-300 manufactured by BYK-Chemie) was changed from 1.92 parts to 5.76 parts. Except for the above, the same procedure as in Example 1 was carried out to obtain Ink 4.

[0231] Example 5: Preparation of Ink 5 In Example 1, 1.92 parts of the surface conditioner (BYK-300 manufactured by BYK-Chemie) was changed to 4 parts of another surface conditioner (BYK-310 manufactured by BYK-Chemie, a xylene solution containing 25% by mass of polyester-modified polymethylalkylsiloxane and components excluding organic solvents). Ink 5 was obtained in the same manner as in Example 1, except for the above points.

[0232] Example 6: Preparation of Ink 6 In Example 1, 1.92 parts of the surface conditioner (BYK-300 manufactured by BYK-Chemie) was changed to 6.66 parts of another surface conditioner (BYK-314 manufactured by BYK-Chemie, a propylene glycol monomethyl ether (PGM):phenyl glycol = 7:5 solution with 15 mass% of components excluding polyester-modified polymethylalkylsiloxane and organic solvent). Ink 6 was obtained in the same manner as in Example 1 except for the above points.

[0233] Example 7: Preparation of Ink 7 In Example 1, 1.92 parts of the surface conditioner (BYK-300 manufactured by BYK-Chemie) was changed to 1 part of another surface conditioner (Ftergent 208G manufactured by Neos, a fluorine-containing polyoxyethylene ether). Except for the above, Ink 7 was obtained in the same manner as in Example 1.

[0234] Example 8: Preparation of Ink 8 In Example 1, 1.92 parts of the surface conditioner (BYK-300 manufactured by BYK-Chemie) was changed to 1 part of another surface conditioner (DISPARLON UVX-36, an acrylic copolymer manufactured by Kusumoto Chemicals Co., Ltd.) Ink 8 was obtained in the same manner as in Example 1 except for the above points.

[0235] Comparative Example 1: Preparation of Ink 9 The surface conditioner (BYK-300 manufactured by BYK-Chemie) was not used in Example 1. Ink 9 was obtained in the same manner as in Example 1 except for the above points.

[0236] Comparative Example 2: Preparation of Ink 10 In Example 1, the amount of surface conditioner (BYK-300 manufactured by BYK-Chemie) was changed from 1.92 parts to 0.96 parts. Ink 10 was obtained in the same manner as in Example 1 except for the above points.

[0237] Comparative Example 3: Preparation of Ink 11 In Example 1, the amount of propylene glycol monomethyl ether acetate (PGMEA) was changed from 420 parts to 260 parts. Ink 11 was obtained in the same manner as in Example 1 except for the above points.

[0238] Comparative Example 4: Preparation of Ink 12 In Example 1, 1) The amount of propylene glycol monomethyl ether acetate (PGMEA) was changed from 420 parts to 260 parts. 2) The amount of surface conditioner (BYK-300 manufactured by BYK-Chemie) was changed from 1.92 parts to 5.76 parts. Ink 12 was obtained in the same manner as in Example 1 except for the above.

[0239] Comparative Example 5: Preparation of Ink 13 In Example 1, the amount of surface conditioner (BYK-300 manufactured by BYK-Chemie) was changed from 1.92 parts to 9.6 parts. Ink 13 was obtained in the same manner as in Example 1 except for the above points.

[0240] Comparative Example 6: Preparation of Ink 14 In Example 1, 1) The amount of methyl ethyl ketone (MEK) was changed from 26.5 parts to 196.5 parts. 2) The amount of propylene glycol monomethyl ether acetate (PGMEA) was changed from 420 parts to 250 parts. Ink 14 was obtained in the same manner as in Example 1 except for the above.

[0241] Comparative Example 7: Preparation of Ink 15 In addition, 120 parts of N-methylpyrrolidone (NMP) was added to the same procedure as in Example 1. Ink 15 was obtained in the same manner as in Example 1 except for the above points.

[0242] Comparative Example 8: Preparation of Ink 16 In Example 1, the amount of propylene glycol monomethyl ether acetate (PGMEA) was changed from 420 parts to 600 parts. Ink 16 was obtained in the same manner as in Example 1 except for the above points.

[0243] <Test Example 1: Viscosity Measurement> The viscosity of the ink obtained in each example and comparative example was measured using an E-type viscometer ("RE80 type viscometer" manufactured by Toki Sangyo Co., Ltd.) for 2 minutes under the following conditions: measurement temperature 25°C, rotor 1.34° x R24, ink volume 1.2 ml, and rotation speed 50 rpm.

[0244] <Test Example 2: Measurement of surface tension> The surface tension of the ink obtained in each example and comparative example was measured. Specifically, the surface tension was measured by the hanging drop method using a contact angle meter ("DMs-401" manufactured by Kyowa Interface Science Co., Ltd.) at a measurement temperature of 25°C. The measurement was carried out five times, and the average value of the five measurements was taken as the surface tension of the ink.

[0245] <Test Example 3: Inkjet ejection test> The inks obtained in each example and comparative example were loaded into an inkjet nozzle (Konica Minolta "KM1024A," piezo-driven) and an inkjet ejection test was conducted. Specifically, inks that could apply uniform droplets from the nozzle were rated as "good" (◯). Ink containing minute air bubbles and resulting in poor ejection from some nozzles was rated as "bubble trap" (×). Ink with high viscosity that prevented droplets from being ejected from the nozzle was rated as "un-ejectable" (×). Nozzle drying was evaluated by interrupting the ejection for a certain period of time and then ejecting again. Ink that dried out and clogged the nozzle after a 5-minute interruption was rated as "dry" (×). Ink that was not problematic after a 5-minute interruption but dried out and clogged the nozzle after a 10-minute interruption was rated as "dry" (△). Ink that did not dry out and clog the nozzle after a 10-minute interruption was rated as "good" (◯).

[0246] <Test Example 4: Measurement of average coefficient of linear thermal expansion (CTE)> The ink for which the ejection test result in Test Example 3 was "good" = "◯" was again loaded into an inkjet nozzle (Konica Minolta's "KM1024A"). Next, ink was inkjet coated onto a polyimide film (UBE's "Upilex") so that the ink would have a film thickness of 10 μm after drying. The polyimide film on which the coating film was formed was dried in an oven at 130°C for 5 minutes. After drying, the coating film was thermally cured by heating at 200°C for 90 minutes, and the polyimide film was then peeled off to obtain Evaluation Sample A.

[0247] Evaluation Sample A was cut into a piece approximately 5 mm wide and 15 mm long to obtain a test piece (Evaluation Sample B). Evaluation Sample B was subjected to thermomechanical analysis using a tensile load method using a thermomechanical analyzer (Rigaku Corporation, Thermo Plus TMA8310). Specifically, Evaluation Sample B was loaded into the thermomechanical analyzer and thermal expansion coefficients were measured twice consecutively under conditions of a 1 g load and a heating rate of 5°C / min (the first measurement was to 200°C, and the second measurement was to 260°C). Based on the results of the second measurement, the average linear thermal expansion coefficient (ppm / K) from 25°C (298K) to 150°C (423K) was calculated. A mean linear thermal expansion coefficient of less than 30 ppm / K was evaluated as "Good," and a mean linear thermal expansion coefficient of 30 ppm / K or greater was evaluated as "Poor."

[0248] <Test Example 5: Ink Sedimentation Evaluation Test> The inks obtained in each example and comparative example were allowed to stand for three days under each of the following conditions: room temperature, refrigerated at 5°C, and frozen at -25°C. In the inks that were allowed to stand, those in which the inorganic filler did not settle were evaluated as "Good," and those in which the inorganic filler settled under either condition were evaluated as "Poor."

[0249] <Test Example 6: Measurement of dielectric loss tangent (Df)> A PET film ("Lumirror R80" manufactured by Toray Industries, Inc., thickness: 38 μm, softening point: 130° C.) that had been treated with an alkyd resin-based release agent ("AL-5" manufactured by Lintec Corporation) was prepared as a support. The ink obtained in each example and comparative example was uniformly applied to the support using a die coater so that the thickness of the resin composition layer after drying would be 15 μm, and the resulting layer was dried in an oven at 130° C. for 5 minutes to form a resin composition layer.

[0250] The resin composition layer was heated at 200°C for 90 minutes to thermally cure the resin composition layer, and then the support was peeled off to obtain a cured product. The obtained cured product was cut into a piece 2 mm wide and 80 mm long to obtain a test piece for evaluation (Evaluation Sample C). For Evaluation Sample C, the dielectric loss tangent (Df) was measured using an Agilent Technologies HP8362B by the cavity resonance perturbation method at a measurement frequency of 5.8 GHz and a measurement temperature of 23°C. Measurements were performed on five test pieces, and the average value was calculated.

[0251] Table 1

[0252] Table 2

[0253] Table 3

Claims

1. An inkjet ink comprising: (A) an epoxy resin; (B) an organic solvent; (C) an inorganic filler; and (D) a surface conditioner, The component (B) contains (B-1) an organic solvent having a boiling point of 135°C or higher and 190°C or lower, the content of component (B) is 50% by mass or more and 60% by mass or less, based on 100% by mass of all components in the ink; the content of component (D) is 0.15% by mass or more and 1% by mass or less, based on 100% by mass of all components in the ink excluding the organic solvent; An inkjet ink, wherein the content of the component (B-1) is 50% by mass or more relative to 100% by mass of the component (B).

2. 2. The ink-jet ink according to claim 1, wherein the component (D) comprises a polysiloxane compound (D-1).

3. 3. The ink-jet ink according to claim 2, wherein the component (D-1) has a polydialkylsiloxane structure represented by the following formula (d1-1) and a modified polydialkylsiloxane structure represented by the following formula (d1-2) or formula (d1-3): 【Chemistry 1】 (In formulas (d1-1) to (d1-3), R １１ , R ２１ and R ３１ each independently represents an alkyl group having 1 to 8 carbon atoms; R ２２ and R ３２ each independently represents an alkylene group having 1 to 6 carbon atoms; R ２３ represents a hydrogen atom or a methyl group; R ２４ and R ３５ each independently represents an alkyl group or an aralkyl group; R ３３ and R ３４ each independently represents a divalent hydrocarbon group having 1 to 6 carbon atoms; m and n each independently represent an integer of 3 to 300; * represents a bond.)

4. 2. The ink-jet ink according to claim 1, wherein the average particle size of component (C) is 1 μm or less.

5. 2. The ink-jet ink according to claim 1, wherein the component (B) further comprises one or more organic solvents selected from (B-2) organic solvents having a boiling point of less than 135°C and (B-3) organic solvents having a boiling point of more than 190°C.

6. 2. The ink-jet ink according to claim 1, wherein component (B) further comprises (B-2) an organic solvent having a boiling point of less than 135°C.

7. 2. The ink-jet ink according to claim 1, wherein the viscosity measured using an E-type viscometer at 25°C and 50 rpm is 20 mPa·s or less.

8. 2. The ink-jet ink according to claim 1, wherein the surface tension measured by the hanging drop method at 25[deg.] C. is 20 mN / m or more and 50 mN / m or less.

9. 2. The ink-jet ink according to claim 1, wherein the ink is thermally cured at 200°C for 90 minutes and the cured product has a dielectric loss tangent (Df) of 0.005 or less when measured at 5.8 GHz and 23°C.

10. A cured product of the inkjet ink according to any one of claims 1 to 9.

11. A support and a resin composition layer formed on the support, A resin sheet, wherein the resin composition layer comprises the inkjet ink according to any one of claims 1 to 9.

12. A circuit board comprising a cured product of the ink-jet ink according to any one of claims 1 to 9.

13. A semiconductor device comprising the circuit board according to claim 12.

14. A method for manufacturing a circuit board, comprising: (i) applying the inkjet ink according to any one of claims 1 to 9 onto a substrate by an inkjet method; (ii) forming a resin composition layer by drying the inkjet ink; (iii) forming an insulating layer by curing the resin composition layer; A method for manufacturing a circuit board, comprising:

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