JP5799144B2 - Curable composition for inkjet and method for producing electronic component - Google Patents

Description

  The present invention is an ink-jet curable composition that is applied by an ink-jet method and is suitably used for forming a cured product layer such as a resist pattern on a substrate, and a curing formed by the ink-jet curable composition. The present invention relates to a method for manufacturing an electronic component having a physical layer.

  Conventionally, a printed wiring board in which a solder resist pattern, which is a patterned solder resist film, is formed on a substrate on which wiring is provided on the upper surface is often used. With the miniaturization and high density of electronic devices, printed circuit boards are required to have a finer solder resist pattern.

  As a method for forming a fine solder resist pattern, a method of applying a solder resist composition by an ink jet method has been proposed. In the inkjet method, the number of steps is smaller than in the case of forming a solder resist pattern by a screen printing method. For this reason, the solder resist pattern can be easily and efficiently formed by the inkjet method.

  When the solder resist composition is applied by an inkjet method, it is required that the viscosity at the time of application is low to some extent. On the other hand, in recent years, an inkjet apparatus capable of printing by heating to 50 ° C. or higher has been developed. By heating the solder resist composition to 50 ° C. or higher in the ink jet apparatus, the viscosity of the solder resist composition becomes relatively low, and the ejectability of the solder resist composition using the ink jet apparatus is further enhanced. be able to.

  Also, a solder resist composition that can be applied by an ink jet method is disclosed in Patent Document 1 below. Patent Document 1 below discloses inkjet curing comprising a monomer having a (meth) acryloyl group and a thermosetting functional group, a photoreactive diluent having a weight average molecular weight of 700 or less, and a photopolymerization initiator. A sex composition is disclosed. The viscosity of the curable composition for inkjet at 25 ° C. is 150 mPa · s or less.

WO2004 / 099272A1

  The viscosity of the curable composition for inkjet described in Patent Document 1 is relatively low. For this reason, the curable composition for inkjet described in Patent Document 1 can be coated on a substrate by an inkjet method.

  However, since the curable composition for inkjet described in Patent Document 1 contains a monomer having a (meth) acryloyl group and a thermosetting functional group, there is a problem that the pot life under an environment of 50 ° C. or higher is short. is there.

  For example, when an inkjet curable composition is ejected by an inkjet device, the inkjet curable composition generally remains in the inkjet device for a certain period of time after being supplied into the inkjet device. On the other hand, the temperature in the ink jet apparatus may be heated to 50 ° C. or higher in order to improve the ejection property. In the curable composition for inkjet described in Patent Document 1, the composition is cured in an inkjet apparatus heated to 50 ° C. or more, and the viscosity of the composition is increased. It can be difficult.

  Furthermore, the conventional inkjet curable composition also has a problem that the cured product after curing has low heat resistance and insulation reliability.

  An object of the present invention is a curable composition that is applied by an ink jet method, and includes a compound having a cyclic ether group, and is potted even in an environment in an ink jet apparatus that is heated to 50 ° C. or higher. An object is to provide a curable composition for inkjet having a long life and excellent insulation reliability by a cured product after curing, and a method for producing an electronic component using the curable composition for inkjet.

  Another object of the present invention is to provide a curable composition for inkjet which is excellent in heat resistance of a cured product after curing, and a method for producing an electronic component using the curable composition for inkjet.

  According to a wide aspect of the present invention, there is provided a curable composition for inkjet that is applied by an inkjet method and is curable by application of heat, including a compound having a cyclic ether group, and a curing agent, There is provided a curable composition for inkjet, wherein the curing agent is a reaction viscous product obtained by reacting dicyandiamide and a functional group-containing compound having a functional group capable of reacting with dicyandiamide.

  The functional group-containing compound to be reacted with the dicyandiamide preferably has at least one functional group selected from the group consisting of a hydroxyl group, a cyclic ether group, a carboxyl group, and an isocyanate group.

  The functional group-containing compound that reacts with the dicyandiamide is preferably a compound having an epoxy group. The compound having the epoxy group to be reacted with the dicyandiamide preferably has one epoxy group. The functional group-containing compound to be reacted with the dicyandiamide preferably has an aromatic skeleton. The reaction viscous product is preferably a reaction viscous product obtained by reacting the functional group-containing compound with 1 mol or more and 3 mol or less with respect to 1 mol of dicyandiamide.

  In a specific aspect of the curable composition for inkjet according to the present invention, the dicyandiamide that is reacted with the functional group-containing compound is in a powder form.

  In still another specific aspect of the curable composition for inkjet according to the present invention, the reaction viscous material is dissolved in the curable composition.

  In another specific aspect of the curable composition for inkjet according to the present invention, the curable composition for inkjet that is applied by an inkjet method and is curable by irradiation with light and application of heat, A polyfunctional compound having two or more (meth) acryloyl groups and a photopolymerization initiator are further included.

  The photopolymerization initiator is preferably an α-aminoalkylphenone type photoradical polymerization initiator. The photopolymerization initiator is more preferably an α-aminoalkylphenone type photoradical polymerization initiator having a dimethylamino group.

  In another specific aspect of the curable composition for inkjet according to the present invention, the polyfunctional compound having two or more (meth) acryloyl groups has a polycyclic skeleton and two (meth) acryloyl groups. It is a polyfunctional compound having the above.

In still another specific aspect of the curable composition for inkjet according to the present invention, a monofunctional compound having a polycyclic skeleton and having one (meth) acryloyl group is further included.
In still another specific aspect of the curable composition for inkjet according to the present invention, the polyfunctional compound having two or more (meth) acryloyl groups has a polycyclic skeleton, and 2 (meth) acryloyl groups. A polyfunctional compound having at least one polyfunctional compound further having a polycyclic skeleton and having one (meth) acryloyl group is further included.

  In another specific aspect of the curable composition for inkjet according to the present invention, the content of the polyfunctional compound is 20 in a total of 100% by weight of the polyfunctional compound, the monofunctional compound, and the photopolymerization initiator. The content of the monofunctional compound is 5% by weight or more and 50% by weight or less.

  The monofunctional compound comprises isobornyl (meth) acrylate, dihydroxycyclopentadienyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, and dicyclopentanyl (meth) acrylate. It is preferably at least one selected from the group. The polyfunctional compound is preferably tricyclodecane dimethanol di (meth) acrylate.

  The reaction viscous product is preferably a reaction product obtained by reacting the functional group of the functional group-containing compound with a part of the active hydrogen of dicyandiamide.

  In the curable composition for inkjet according to the present invention, the viscosity at 25 ° C. measured according to JIS K2283 is preferably 160 mPa · s or more and 1200 mPa · s or less.

  Moreover, according to the wide aspect of this invention, the process for apply | coating the inkjet curable composition comprised according to this invention by the inkjet system, and drawing it in a pattern form, and the said inkjet use drawn in the pattern form A method for producing an electronic component is provided, comprising: applying heat to a curable composition and curing the composition to form a cured product layer.

In a specific aspect of the method for manufacturing an electronic component according to the present invention, a method for manufacturing a printed wiring board, which is an electronic component having a resist pattern, the inkjet curable composition is applied by an inkjet method. Then, a resist pattern is formed by drawing in a pattern and applying heat to the curable composition for inkjet drawn in the pattern to be cured.
In another specific aspect of the method for producing an electronic component according to the present invention, as the inkjet curable composition, an inkjet printer comprising a polyfunctional compound having two or more (meth) acryloyl groups and a photopolymerization initiator. In the step of forming the cured product layer using the curable composition, light and heat are applied to the curable composition for inkjet drawn in a pattern and cured to form a cured product layer. To do.

  The curable composition for inkjet according to the present invention includes a compound having a cyclic ether group and a curing agent, and the curing agent further reacts dicyandiamide and a functional group-containing compound having a functional group capable of reacting with the dicyandiamide. Since it is a reaction viscous product, it can be applied by an ink jet method.

  Furthermore, the curable composition for inkjet according to the present invention has the above composition, and in particular, because the curing agent is the specific reaction viscous product, the environment within the inkjet apparatus heated to 50 ° C. or higher. But the pot life is long enough. Moreover, since the compound which has a cyclic ether group is contained, the heat resistance of hardened | cured material is high. Moreover, since the said hardening | curing agent is the said specific reaction viscous material, the insulation reliability by hardened | cured material becomes favorable.

  Details of the present invention will be described below.

(Curable composition for inkjet)
The curable composition for inkjet according to the present invention includes a compound (C) having a cyclic ether group and a curing agent (D). It is preferable that the curable composition for inkjet according to the present invention further includes a polyfunctional compound (A) having two or more (meth) acryloyl groups and a photopolymerization initiator (B). The curing agent (D) is a reaction viscous product obtained by reacting dicyandiamide with a functional group-containing compound having a functional group capable of reacting with the dicyandiamide. The term “(meth) acryloyl group” refers to an acryloyl group and a methacryloyl group.

  Since the curable composition for inkjet according to the present invention contains the compound (C) having a cyclic ether group and the curing agent (D), it can be cured by application of heat. Therefore, the curable composition for inkjet according to the present invention is a thermosetting composition for inkjet. When the curable composition for inkjet according to the present invention contains the polyfunctional compound (A) and the photopolymerization initiator (B), the curable composition for inkjet according to the present invention is irradiated with light and heat. The composition is curable by application of an ink and is a light and thermosetting composition for inkjet.

  The curable composition for ink jet according to the present invention can be cured by applying heat to obtain a cured product layer such as a resist pattern which is a cured product. Moreover, when the curable composition for inkjet according to the present invention contains a polyfunctional compound (A) and a photopolymerization initiator (B), a primary cured product is obtained after obtaining a primary cured product by light irradiation. It is possible to obtain a cured product layer such as a resist pattern, which is a cured product, by applying heat to the film. Thus, by performing primary curing by light irradiation, wetting and spreading of the curable composition for inkjet applied onto a coating target member such as a substrate can be suppressed. Therefore, a cured product layer such as a fine resist pattern can be formed with high accuracy.

  Since the curable composition for inkjet according to the present invention contains the compound (C) having a cyclic ether group and the curing agent (D), and further the curing agent (D) is the reaction viscous product, the cyclic ether. Although the compound (C) having a group and the curing agent (D) are contained, the pot life can be sufficiently lengthened even in an environment in an ink jet apparatus heated to 50 ° C. or higher. Moreover, even if the curable composition for inkjet before the coating by the inkjet method is heated to 50 ° C. or higher, the viscosity does not easily increase and the thermal curing does not easily proceed. For this reason, the curable composition for inkjet is excellent in stability at high temperatures, and can be stably discharged from the inkjet nozzle. For this reason, a cured product layer such as a uniform resist pattern can be formed.

  On the other hand, when dicyandiamide that is not a reaction viscous material is used, since dicyandiamide is solid at normal temperature (23 ° C.), other components in the curable composition (when solid content is included) Is incompatible with (except for solids). That is, dicyandiamide that is not the reaction viscous substance exists as a solid in the curable composition and does not dissolve in the curable composition. For this reason, when the conventional dicyandiamide is used as a curing agent, the inkjet head is clogged when the curable composition is discharged by the inkjet method. When clogging occurs, ejection becomes difficult or impossible, and a cured product layer such as a resist pattern becomes non-uniform. In addition, even if dicyandiamide is finely pulverized to a size that can be ejected by ink jetting, the hydrophilicity (water absorption) of the pulverized product tends to cause dielectric breakdown starting from the pulverized product, and the reliability tends to decrease. is there.

  Moreover, since the curable composition for inkjet which concerns on this invention contains the compound (C) which has a cyclic ether group especially, it can improve the heat resistance of the hardened | cured material after hardening.

  Furthermore, since the hardening | curing agent (D) is the said reaction viscous material especially in the curable composition for inkjet which concerns on this invention, the insulation reliability by the hardened | cured material after hardening can also be improved. The curable composition for inkjet according to the present invention has the above composition, and in particular, the curing agent (D) is the above reaction viscous product, whereby the insulation reliability due to the cured product after curing is increased. The inventors have found. For example, when the reaction viscous material using dicyandiamide is used, the insulation reliability by the cured material is considerably higher than when the imidazole curing agent or the like is used.

  Hereinafter, the detail of each component contained in the curable composition for inkjet which concerns on this invention is demonstrated.

[Polyfunctional compound (A)]
In order to cure the curable composition by light irradiation, the curable composition for inkjet according to the present invention preferably contains a polyfunctional compound (A) having two or more (meth) acryloyl groups. The polyfunctional compound (A) is not particularly limited as long as it has two or more (meth) acryloyl groups. As the polyfunctional compound (A), a conventionally known polyfunctional compound having two or more (meth) acryloyl groups can be used. Since the polyfunctional compound (A) has two or more (meth) acryloyl groups, polymerization proceeds and cures upon irradiation with light. For this reason, curing can be advanced by irradiating light after coating the curable composition, the applied shape can be maintained, and primary curing of the curable composition irradiated with light. It can suppress effectively that a thing and hardened | cured material spread out too much. As for a polyfunctional compound (A), only 1 type may be used and 2 or more types may be used together.

  As the polyfunctional compound (A), (meth) acrylic acid adducts of polyhydric alcohols, (meth) acrylic acid adducts of alkylene oxide modified products of polyhydric alcohols, urethane (meth) acrylates, and polyesters (meth) Examples include acrylates. Examples of the polyhydric alcohol include diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, trimethylol propane, cyclohexane dimethanol, tricyclodecane dimethanol, an alkylene oxide adduct of bisphenol A, and Examples include pentaerythritol. The term “(meth) acrylate” refers to acrylate and methacrylate. The term “(meth) acryl” refers to acrylic and methacrylic.

  The polyfunctional compound (A) is preferably a polyfunctional compound (A1) having a polycyclic skeleton and having two or more (meth) acryloyl groups. By using the polyfunctional compound (A1), the heat and moisture resistance of the cured product of the curable composition for inkjet can be increased. Therefore, the printed wiring board using the curable composition for inkjet according to the present invention can be used for a long period of time, and the reliability of the printed wiring board can be enhanced.

  The polyfunctional compound (A1) is not particularly limited as long as it has a polycyclic skeleton and two or more (meth) acryloyl groups. As the polyfunctional compound (A1), a conventionally known polyfunctional compound having a polycyclic skeleton and having two or more (meth) acryloyl groups can be used. Since the polyfunctional compound (A1) has two or more (meth) acryloyl groups, the polymerization proceeds and is cured by light irradiation. As for a polyfunctional compound (A1), only 1 type may be used and 2 or more types may be used together.

  Polyfunctional compounds (A1) include polyhydric alcohol (meth) acrylic acid adducts, polyhydric alcohol alkylene oxide-modified (meth) acrylic acid adducts, urethane (meth) acrylates, and polyester (meth). Examples include acrylates. Examples of the polyhydric alcohol include diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol, trimethylolpropane, and pentaerythritol.

  Specific examples of the polyfunctional compound (A1) include tricyclodecane dimethanol di (meth) acrylate, isobornyl dimethanol di (meth) acrylate, dicyclopentenyl dimethanol di (meth) acrylate, and the like. Especially, it is preferable that a polyfunctional compound (A1) is tricyclodecane dimethanol di (meth) acrylate from a viewpoint of improving the heat-and-moisture resistance of hardened | cured material further. The term “(meth) acrylate” refers to acrylate and methacrylate.

  The “polycyclic skeleton” in the polyfunctional compound (A1) and the monofunctional compound (E) described later indicates a structure having a plurality of cyclic skeletons continuously. Examples of the polycyclic skeleton in the polyfunctional compound (A1) and the monofunctional compound (E) include a polycyclic alicyclic skeleton and a polycyclic aromatic skeleton.

  Examples of the polycyclic alicyclic skeleton include a bicycloalkane skeleton, a tricycloalkane skeleton, a tetracycloalkane skeleton, and an isobornyl skeleton.

  Examples of the polycyclic aromatic skeleton include naphthalene ring skeleton, anthracene ring skeleton, phenanthrene ring skeleton, tetracene ring skeleton, chrysene ring skeleton, triphenylene ring skeleton, tetraphen ring skeleton, pyrene ring skeleton, pentacene ring skeleton, picene ring skeleton and Examples include perylene ring skeletons.

  The compounding quantity of a polyfunctional compound (A) is suitably adjusted so that it may harden | cure moderately by irradiation of light, and is not specifically limited. As an example of the blending amount of the polyfunctional compound (A), the content of the polyfunctional compound (A) is 0% by weight or more, preferably 20% by weight or more, in 100% by weight of the curable composition for inkjet. Preferably it is 40 weight% or more, More preferably, it is 60 weight% or more, Preferably it is 95 weight% or less, More preferably, it is 90 weight% or less. In 100% by weight of the curable composition for inkjet, the upper limit of the content of the polyfunctional compound (A) is appropriately adjusted depending on the contents of the components (B) to (D) and other components.

  When the polyfunctional compound (A1) and the monofunctional compound (E) to be described later are used in combination, the polyfunctional compound (A1), the monofunctional compound (E), and the photopolymerization initiator (B) in a total of 100% by weight The content of the polyfunctional compound (A1) is preferably 20% by weight or more and 70% by weight or less. In 100% by weight of the curable composition for inkjet, the content of the polyfunctional compound (A1) is more preferably 40% by weight or more, and more preferably 60% by weight or less. When the content of the polyfunctional compound (A1) is not less than the above lower limit, the curable composition can be more effectively cured by light irradiation. When the content of the polyfunctional compound (A1) is not more than the above upper limit, the moisture and heat resistance of the cured product is further increased.

[Photoinitiator (B)]
In order to cure the curable composition by light irradiation, the curable composition for inkjet according to the present invention preferably contains a photopolymerization initiator (B) together with the polyfunctional compound (A). Examples of the photopolymerization initiator (B) include a photoradical polymerization initiator and a photocationic polymerization initiator. The photopolymerization initiator (B) is preferably a radical photopolymerization initiator. As for a photoinitiator (B), only 1 type may be used and 2 or more types may be used together.

  The photo radical polymerization initiator is not particularly limited. The photo radical polymerization initiator is a compound for generating radicals upon light irradiation and initiating a radical polymerization reaction. Specific examples of the photo radical polymerization initiator include, for example, benzoin, benzoin alkyl ethers, acetophenones, aminoacetophenones, anthraquinones, thioxanthones, ketals, 2,4,5-triarylimidazole dimers, Examples include riboflavin tetrabutyrate, thiol compounds, 2,4,6-tris-s-triazine, organic halogen compounds, benzophenones, xanthones, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide. As for the said radical photopolymerization initiator, only 1 type may be used and 2 or more types may be used together.

  Examples of the benzoin alkyl ethers include benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether. Examples of the acetophenones include acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone and 1,1-dichloroacetophenone. Examples of the aminoacetophenones include 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butane. Examples include -1-one and N, N-dimethylaminoacetophene. Examples of the anthraquinones include 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone and 1-chloroanthraquinone. Examples of the thioxanthones include 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone. Examples of the ketals include acetophenone dimethyl ketal and benzyl dimethyl ketal. Examples of the thiol compound include 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, and 2-mercaptobenzothiazole. Examples of the organic halogen compound include 2,2,2-tribromoethanol and tribromomethylphenyl sulfone. Examples of the benzophenones include benzophenone and 4,4'-bisdiethylaminobenzophenone.

  The photo radical polymerization initiator is preferably an α-aminoalkylphenone type photo radical polymerization initiator, and more preferably an α-aminoalkyl phenone type photo radical polymerization initiator having a dimethylamino group. By using this specific radical photopolymerization initiator, the curable composition for inkjet can be efficiently photocured even if the exposure amount is small. For this reason, it can suppress effectively that the coated curable composition for inkjet by wet irradiation spreads, and can form a fine resist pattern with high precision. Further, when the photo radical polymerization initiator is an α-aminoalkylphenone type photo polymerization initiator having a dimethylamino group, the thermosetting speed can be increased, and the thermosetting property of the light irradiated product of the composition can be increased. Can be improved.

  The present inventors can not only improve the photocurability but also improve the thermosetting property by using an α-aminoalkylphenone type photoradical polymerization initiator having a dimethylamino group. I found. The α-aminoalkylphenone type photoradical polymerization initiator having a dimethylamino group is a component that greatly contributes to improvement of thermosetting. Furthermore, the heat resistance and insulation reliability of the cured product can be enhanced by using an α-aminoalkylphenone type photoradical polymerization initiator having a dimethylamino group. Even if an electronic component such as a printed wiring board having a resist pattern formed by the curable composition for inkjet according to the present invention is used for a long time under a high humidity condition, the insulation resistance is excellent. Is kept high enough.

  Specific examples of the α-aminoalkylphenone photoradical polymerization initiator include IRGACURE907, IRGACURE369, IRGACURE379, and IRGACURE379EG manufactured by BASF. Other α-aminoalkylphenone type photopolymerization initiators may be used. Among them, from the viewpoint of further improving the photocurability of the curable composition for inkjet and the insulation reliability due to the cured product, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone. -1 (IRGACURE369) or 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone (IRGACURE379 or IRGACURE379EG) is preferred. These are α-aminoalkylphenone type photoradical polymerization initiators having a dimethylamino group.

  A photopolymerization initiation assistant may be used together with the photo radical polymerization initiator. Examples of the photopolymerization initiation assistant include N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, and triethanolamine. Photopolymerization initiation assistants other than these may be used. As for the said photoinitiation adjuvant, only 1 type may be used and 2 or more types may be used together.

  In addition, a titanocene compound such as CGI-784 (manufactured by Ciba Specialty Chemicals) having absorption in the visible light region may be used to promote the photoreaction.

  It does not specifically limit as said photocationic polymerization initiator, For example, a sulfonium salt, an iodonium salt, a metallocene compound, a benzoin tosylate etc. are mentioned. As for the said photocationic polymerization initiator, only 1 type may be used and 2 or more types may be used together.

  The content of the photopolymerization initiator (B) with respect to 100 parts by weight of the polyfunctional compound (A) is preferably 0.1 parts by weight or more, more preferably 1 part by weight or more, and further preferably 3 parts by weight or more. The amount is preferably 30 parts by weight or less, more preferably 15 parts by weight or less, and still more preferably 10 parts by weight or less. When the content of the photopolymerization initiator (B) is not less than the above lower limit and not more than the above upper limit, the curable composition is more effectively cured by light irradiation.

[Compound having cyclic ether group (C)]
The curable composition for inkjet according to the present invention contains a compound (C) having a cyclic ether group so that it can be cured by application of heat. By using the compound (C), the curable composition or the primary cured product of the curable composition can be further cured by applying heat. For this reason, by using compound (C), a resist pattern can be formed efficiently and accurately, and the heat resistance and insulation reliability of the cured product can be further increased. Only 1 type may be used for the compound (C) which has a cyclic ether group, and 2 or more types may be used together.

The compound (C) having a cyclic ether group is not particularly limited as long as it has a cyclic ether group. Examples of the cyclic ether group in the compound (C) include an epoxy group and an oxetanyl group. Of these, the cyclic ether group is preferably an epoxy group from the viewpoint of enhancing curability and obtaining a cured product that is more excellent in heat resistance and insulation reliability. The compound (C) having a cyclic ether group preferably has two or more cyclic ether groups.
Specific examples of compounds having an epoxy group include heterocyclic epoxy compounds such as bisphenol S type epoxy compounds, diglycidyl phthalate compounds, triglycidyl isocyanurates, bixylenol type epoxy compounds, biphenol type epoxy compounds, tetraglycidyl xylenoyl Ethane compound, bisphenol A type epoxy compound, hydrogenated bisphenol A type epoxy compound, bisphenol F type epoxy compound, brominated bisphenol A type epoxy compound, phenol novolac type epoxy compound, cresol novolac type epoxy compound, alicyclic epoxy compound, bisphenol A novolac type epoxy compound, chelate type epoxy compound, glyoxal type epoxy compound, amino group-containing epoxy compound, rubber-modified epoxy compound , Dicyclopentadiene phenolic type epoxy compounds, silicone-modified epoxy compounds and ε- caprolactone-modified epoxy compounds and the like.

  The compound (C) having a cyclic ether group preferably has an aromatic skeleton. By using a compound having an aromatic skeleton and a cyclic ether group, the thermal stability during storage and ejection of the curable composition is further improved, and gelation is less likely to occur during storage of the curable composition. . In addition, a compound having an aromatic skeleton and a cyclic ether group has a polyfunctional compound (A), a monofunctional compound (E) and a curing agent (C) as compared with a compound having no aromatic skeleton and having a cyclic ether group. ), The insulation reliability is further improved.

  The compound having an oxetanyl group is exemplified in, for example, Japanese Patent No. 3074086.

  The compound (C) having a cyclic ether group is preferably liquid at 25 ° C. The viscosity of the compound (C) having a cyclic ether group at 25 ° C. preferably exceeds 300 mPa · s. The viscosity at 25 ° C. of the compound (C) having a cyclic ether group is preferably 80 Pa · s or less. When the viscosity of the compound (C) having a cyclic ether group is not less than the above lower limit, the resolution when forming the cured product layer is further improved. When the viscosity of the compound (C) having a cyclic ether group is not more than the above upper limit, the dischargeability of the curable composition is further improved, and the compound (C) having a cyclic ether group and other components The compatibility is further increased, and the insulation reliability is further improved.

  The compounding quantity of the compound (C) which has a cyclic ether group is suitably adjusted so that it may harden | cure moderately by provision of heat, and is not specifically limited. The content of the compound (C) having a cyclic ether group in 100% by weight of the curable composition for inkjet is preferably 3% by weight or more, preferably 99% by weight or less, more preferably 95% by weight or less, and still more preferably 80%. % By weight or less. In 100% by weight of the curable composition for inkjet, the content of the compound (C) having a cyclic ether group is more preferably 5% by weight or more, and still more preferably 10% by weight or more. When the polyfunctional compound (A) and the photopolymerization initiator (B) are used, the content of the compound (C) having a cyclic ether group in 100% by weight of the curable composition for inkjet is particularly preferably 50. % By weight or less, most preferably 40% by weight or less. When the content of the compound (C) is not less than the above lower limit, the curable composition can be more effectively cured by application of heat. When the content of the compound (C) is not more than the above upper limit, the heat resistance of the cured product is further increased.

[Curing agent (D)]
The curing agent (D) is a reaction viscous product obtained by reacting dicyandiamide with a functional group-containing compound having a functional group capable of reacting with the dicyandiamide. Since such a hardening | curing agent (D) is used, the said curable composition can be hardened | cured by provision of heat. Moreover, the insulation reliability by hardened | cured material can be made high by thermosetting the curable composition which used together the compound (C) which has a cyclic ether group, and a hardening | curing agent (D).

  In addition, the said reaction viscous material should just have a viscous property by the reaction viscous material alone before using it for the curable composition for inkjet, and it is not viscous in the curable composition for inkjet. Also good. Moreover, when the said reaction viscous material is taken out from the curable composition for inkjets, this reaction viscous material may be viscous.

  Since dicyandiamide (dicyandiamide particles) that is solid at normal temperature (23 ° C.) exists as a solid in the liquid component, it may settle during storage or cause nozzle clogging of the inkjet head. In order to solve such problems, dicyandiamide is reacted in advance with a functional group-containing compound having a functional group capable of reacting with dicyandiamide to prepare a reaction viscous product and added to the composition. That is, the curable composition for inkjet according to the present invention uses a curing agent (D) that is a reaction viscous product obtained by reacting dicyandiamide with a functional group-containing compound having a functional group capable of reacting with the dicyandiamide. If this hardening | curing agent (D) is used, the insulation reliability by the pot life of a composition and hardened | cured material will become favorable.

  The reaction viscous product (E1) before blended in the curable composition for inkjet is not blended in an organic solvent or blended in an organic solvent and the reaction viscous product (E1). ) The amount of the organic solvent blended with respect to 100 parts by weight is preferably 100 parts by weight or less. When the said reaction viscous material (E1) is mix | blended with the organic solvent, the quantity of the organic solvent mix | blended with respect to 100 weight part of the said reaction viscous material (E1) shall be 50 weight part or less. Is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, and particularly preferably 1 part by weight or less.

  The reaction viscous product is preferably a reaction product obtained by reacting the functional group-containing compound with a part of the active hydrogen of dicyandiamide. The functional group capable of reacting with the dicyandiamide of the functional group-containing compound generally reacts with a part of the active hydrogen of dicyandiamide.

  The dicyandiamide to be reacted with the functional group-containing compound is preferably in a powder form. By reacting powdered dicyandiamide with the functional group-containing compound, the powdery dicyandiamide is not powdered, and the viscous viscous reaction product is obtained.

  From the viewpoint of easily synthesizing the reaction viscous material and obtaining a curable composition having a long pot life, the functional group-containing compound to be reacted with the dicyandiamide includes a hydroxyl group, a cyclic ether group, a carboxyl group, and an isocyanate group. It preferably has at least one functional group selected from the group consisting of:

  From the viewpoint of easily synthesizing the reaction viscous material and obtaining a curable composition having a long pot life, the functional group-containing compound reacted with the dicyandiamide is preferably a compound having a cyclic ether group. . The compound having the cyclic ether group to be reacted with dicyandiamide is preferably a compound having one cyclic ether group.

  From the viewpoint of easily synthesizing the reaction viscous material and obtaining a curable composition having a long pot life, the functional group-containing compound reacted with the dicyandiamide is preferably a compound having an epoxy group. The compound having an epoxy group to be reacted with dicyandiamide is preferably a compound having one epoxy group.

  From the viewpoint of easily synthesizing the reaction viscous material and obtaining a curable composition for inkjet having a longer pot life, from the viewpoint of further improving the heat resistance of the cured product of the curable composition, the dicyandiamide and The functional group-containing compound to be reacted preferably has an aromatic skeleton, more preferably a compound having an aromatic skeleton and a cyclic ether group, and a compound having an aromatic skeleton and an epoxy group. Particularly preferred.

  Specific examples of the functional group-containing compound include phenyl glycidyl ether, butyl glycidyl ether, ortho-cresyl glycidyl ether, meta-cresyl glycidyl ether, para-cresyl glycidyl ether, allyl glycidyl ether, and para-t-butylphenyl glycidyl ether. Examples thereof include glycidyl ethers, glycidyl (meth) acrylate, and 3,4-epoxycyclohexylmethyl (meth) acrylate.

  From the viewpoint of further improving the heat resistance of the cured product, the functional group-containing compound is an aromatic ring-containing phenyl glycidyl ether, ortho-cresyl glycidyl ether, meta-cresyl glycidyl ether, para-cresyl glycidyl ether or para-t-butyl. Preference is given to phenylglycidyl ether.

  In the reaction between the dicyandiamide and the functional group-containing compound, the functional group-containing compound is preferably 0.2 mol or more, more preferably 1 mol or more, preferably 4 mol or less, more preferably 3 mol per mol of dicyandiamide. It is desirable to make it react below mol. That is, the reaction viscous product is preferably 0.2 mol or more, more preferably 1 mol or more, preferably 4 mol or less, more preferably 3 mol or less of the functional group-containing compound with respect to 1 mol of the dicyandiamide. It is desirable that the reaction is a viscous reaction product. From the viewpoint of obtaining a more excellent curable composition by pot life, the reaction viscous product is a reaction viscosity obtained by reacting 1 mol to 3 mol of the functional group-containing compound with respect to 1 mol of the dicyandiamide. It is particularly desirable to be a product. There exists a possibility that unreacted dicyandiamide may precipitate that the usage-amount of the said functional group containing compound is less than the said minimum. When the usage-amount of the said functional group containing compound exceeds the said upper limit, there exists a possibility that all the active hydrogens of the said reaction viscous substance may deactivate, and it becomes impossible to harden a compound (C). In addition, in this reaction, it is preferable to make it react at 60 to 140 degreeC in presence of a solvent or a reaction accelerator as needed.

  In the reaction of the dicyandiamide and the functional group-containing compound, a solvent may be used to dissolve the dicyandiamide. The solvent may be any solvent that can dissolve dicyandiamide. Usable solvents include acetone, methyl ethyl ketone, dimethylformamide, methyl cellosolve and the like.

  In order to promote the reaction between the dicyandiamide and the functional group-containing compound, a reaction accelerator may be used. Known reaction accelerators such as phenols, amines, imidazoles, and triphenylphosphine can be used as the reaction accelerator.

  From the viewpoint of suppressing pot life reduction and curing unevenness, in the curable composition for inkjet according to the present invention, the reaction viscous material is compatible with the compound (C) having a cyclic ether group. Preferably compatible with the compound (A) having two or more (meth) acryloyl groups, preferably compatible with the monofunctional compound (E), and further curable composition It is preferably dissolved in the product.

  The reaction viscous product is preferably compatible with the compound (C) having a cyclic ether group, preferably compatible with the compound (A) having two or more (meth) acryloyl groups, It is preferable that it is compatible with the monofunctional compound (E).

  The said reaction viscous substance is a non-powder-like reaction viscous substance obtained by reaction of a powdery dicyandiamide and the said functional group containing compound, for example. From the viewpoint of further improving the inkjet dischargeability, the reaction viscous material is preferably not a solid, preferably not a crystal, and preferably not a crystalline solid. The reaction viscous material is preferably in a liquid or semi-solid form.

  The reaction viscous product is preferably transparent or translucent. Whether or not the reaction viscous material is transparent or translucent can be determined by whether or not the object is visible when the object is viewed through the reaction viscous material having a thickness of 5 mm.

  The compounding ratio of the compound (C) having a cyclic ether group and the reaction viscous product is not particularly limited. The blending amount of the reaction viscous material is appropriately adjusted so as to be appropriately cured by application of heat, and is not particularly limited. The content of the reaction viscous product is preferably 5 parts by weight or more, more preferably 10 parts by weight or more, preferably 60 parts by weight or less, more preferably 100 parts by weight of the compound (C) having a cyclic ether group. 50 parts by weight or less.

(Monofunctional compound (E))
The curable composition for inkjet according to the present invention preferably contains a monofunctional compound (E) having a polycyclic skeleton and having one (meth) acryloyl group. Furthermore, the curable composition for inkjet according to the present invention includes a polyfunctional compound (A1) having a polycyclic skeleton and having two or more (meth) acryloyl groups, a polycyclic skeleton, and (meta And a monofunctional compound (E) having one acryloyl group. In these cases, the heat-and-moisture resistance of the cured product of the ink-jet curable composition is considerably increased. Therefore, an electronic component such as a printed wiring board using the curable composition for inkjet according to the present invention can be used for a longer period of time, and the reliability of the electronic component is further enhanced. In addition, the use of the monofunctional compound (E) not only increases the heat and moisture resistance of the cured product, but also increases the dischargeability of the curable composition. In addition, when the monofunctional compound (E) having a polycyclic skeleton and having one (meth) acryloyl group is used, it does not have a polycyclic skeleton and has one (meth) acryloyl group. Compared with the case where a monofunctional compound is used, the heat-and-moisture resistance of the cured product is increased.

  The monofunctional compound (E) is not particularly limited as long as it has a polycyclic skeleton and one (meth) acryloyl group. As the monofunctional compound (E), a conventionally known monofunctional compound having a polycyclic skeleton and one (meth) acryloyl group can be used. As for monofunctional compound (E), only 1 type may be used and 2 or more types may be used together.

  Specific examples of the monofunctional compound (E) include isobornyl (meth) acrylate, dihydroxycyclopentadienyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, and dicyclopenta. Examples include nyl (meth) acrylate and naphthyl (meth) acrylate. Among these, from the viewpoint of further improving the heat and heat resistance of the cured product, the monofunctional compound (E) is composed of isobornyl (meth) acrylate, dihydroxycyclopentadienyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclohexane. It is preferably at least one selected from the group consisting of pentenyloxyethyl (meth) acrylate and dicyclopentanyl (meth) acrylate.

  In 100% by weight of the curable composition for inkjet, the content of the monofunctional compound (E) is preferably 5% by weight or more, more preferably 15% by weight or more, preferably 50% by weight or less, more preferably 45% by weight or less. It is.

  The content of the monofunctional compound (E) is 5% by weight or more and 50% by weight or less in the total of 100% by weight of the polyfunctional compound (A1), the monofunctional compound (E), and the photopolymerization initiator (B). It is preferable. In the total of 100% by weight of the polyfunctional compound (A1), the monofunctional compound (E), and the photopolymerization initiator (B), the content of the monofunctional compound (E) is more preferably 15% by weight or more. Is 45% by weight or less. When the content of the monofunctional compound (E) is not less than the above lower limit, the moisture and heat resistance of the cured product is further enhanced. When the content of the monofunctional compound (E) is not more than the above upper limit, the curable composition can be more effectively cured by light irradiation.

  In 100% by weight of the curable composition for inkjet, the upper limit of the total content of the polyfunctional compound (A1) and the monofunctional compound (E) is appropriately adjusted depending on the content of the photopolymerization initiator (B).

[Other ingredients]
The curable composition for inkjet according to the present invention may contain a thermosetting agent other than the reaction viscous material. Furthermore, the curable composition for inkjet according to the present invention may contain a curing accelerator.

  Specific examples of the thermosetting agent include organic acids, amine compounds, amide compounds, hydrazide compounds, imidazole compounds, imidazoline compounds, phenol compounds, urea compounds, polysulfide compounds, and acid anhydrides. A modified polyamine compound such as an amine-epoxy adduct may be used as the thermosetting agent.

  Examples of the curing accelerator include tertiary amines, imidazoles, quaternary ammonium salts, quaternary phosphonium salts, organometallic salts, phosphorus compounds, urea compounds, and the like.

  You may mix | blend various additives with the curable composition for inkjet which concerns on this invention in the range which does not inhibit the objective of this invention. The additive is not particularly limited, and examples thereof include a colorant, a polymerization inhibitor, an antifoaming agent, a leveling agent, and an adhesion imparting agent. Moreover, the curable composition for inkjet according to the present invention may contain an organic solvent as long as the amount is small.

  Examples of the colorant include phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black, and naphthalene black. Examples of the polymerization inhibitor include hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol and phenothiazine. Examples of the antifoaming agent include silicone-based antifoaming agents, fluorine-based antifoaming agents, and polymer-based antifoaming agents. Examples of the leveling agent include silicone leveling agents, fluorine leveling agents, and polymer leveling agents. Examples of the adhesion imparting agent include imidazole adhesion imparting agents, thiazole adhesion imparting agents, triazole adhesion imparting agents, and silane coupling agents.

  In the curable composition for inkjet according to the present invention, the viscosity at 25 ° C. measured in accordance with JIS K2283 is preferably 160 mPa · s or more and 1200 mPa · s or less. When the viscosity of the curable composition for inkjet is not less than the above lower limit and not more than the above upper limit, the curable composition for inkjet can be easily and accurately discharged from the inkjet head. Furthermore, even when the curable composition for inkjet is heated to 50 ° C. or higher, the composition can be easily and accurately discharged from the inkjet head.

  The viscosity is preferably 1000 mPa · s or less, more preferably 500 mPa · s or less. When the above viscosity satisfies the above preferable upper limit, when the curable composition is continuously ejected from the head, the ejectability becomes even better. Moreover, from the viewpoint of further suppressing the wetting and spreading of the curable composition and further increasing the resolution when forming the cured product layer, the viscosity preferably exceeds 500 mPa · s.

  The curable composition for inkjet according to the present invention does not contain an organic solvent, or contains an organic solvent, and the content of the organic solvent in 100% by weight of the curable composition is 50% by weight or less. preferable. In 100% by weight of the curable composition, the content of the organic solvent is more preferably 20% by weight or less, still more preferably 10% by weight or less, and particularly preferably 1% by weight or less. The smaller the content of the organic solvent, the better the resolution when forming the cured product layer.

  The curable composition for inkjet according to the present invention does not contain an organic solvent or contains an organic solvent, and the content of the organic solvent is 50 parts by weight or less with respect to 100 parts by weight of the reaction viscous material (E1). It is preferable that The content of the organic solvent is more preferably 20 parts by weight or less, still more preferably 10 parts by weight or less, and particularly preferably 1 part by weight or less with respect to 100 parts by weight of the reaction viscous product (E1). The smaller the content of the organic solvent, the better the resolution when forming the cured product layer.

(Method for manufacturing electronic parts)
Next, a method for manufacturing an electronic component according to the present invention will be described.

  The manufacturing method of the electronic component which concerns on this invention uses the above-mentioned curable composition for inkjets. That is, in the method for manufacturing an electronic component according to the present invention, first, the curable composition for inkjet is applied by an inkjet method to draw a pattern. At this time, it is particularly preferable to directly draw the curable composition for inkjet. “Direct drawing” means drawing without using a mask. Examples of the electronic component include a printed wiring board and a touch panel component. The electronic component is preferably a wiring board, and more preferably a printed wiring board.

  An ink jet printer is used for application of the ink jet curable composition. The ink jet printer has an ink jet head. The inkjet head has a nozzle. The ink jet device preferably includes a heating unit for heating the temperature in the ink jet device or the ink jet head to 50 ° C. or higher. It is preferable that the said inkjet curable composition is coated on the coating object member. A substrate etc. are mentioned as said coating object member. Examples of the substrate include a substrate having wirings provided on the upper surface. The inkjet curable composition is preferably applied onto a printed circuit board.

  In addition, it is possible to produce a glass substrate for a display device such as a liquid crystal display device by changing the substrate to a member mainly made of glass by the method for manufacturing an electronic component according to the present invention. Specifically, a conductive pattern such as ITO is provided on glass by a method such as vapor deposition, and a cured product layer is formed on the conductive pattern by an inkjet method by the method for manufacturing an electronic component according to the present invention. Good. If a pattern is provided on the cured product layer with a conductive ink or the like, the cured product layer becomes an insulating film, and electrical connection is obtained between predetermined patterns in the conductive pattern on the glass.

  Next, heat is applied to the curable composition for inkjet drawn in a pattern and cured to form a cured product layer. Moreover, when using the curable composition for inkjets containing a polyfunctional compound (A) and a photoinitiator (B) as a curable composition for inkjets, the curable composition for inkjets drawn by pattern shape is used. The material is cured by applying light and heat to form a cured product layer. In this way, an electronic component having a cured product layer can be obtained. The cured product layer may be an insulating film or a resist pattern. The insulating film may be a patterned insulating film. The cured product layer is preferably a resist pattern. The resist pattern is preferably a solder resist pattern.

  The method for manufacturing an electronic component according to the present invention is preferably a method for manufacturing a printed wiring board having a resist pattern. The inkjet curable composition is applied by an inkjet method, drawn in a pattern, and the inkjet curable composition drawn in a pattern is irradiated with light and heat, cured. It is preferable to form a resist pattern.

  The ink-jet curable composition drawn in a pattern may be primarily cured by irradiating light to obtain a primary cured product. Thereby, wetting and spreading of the drawn curable composition for inkjet can be suppressed, and a highly accurate resist pattern can be formed. In addition, when a primary cured product is obtained by light irradiation, the primary cured product may be subjected to main curing by applying heat to obtain a cured product, and a cured product layer such as a resist pattern may be formed. The curable composition for inkjet according to the present invention can be cured by light irradiation and heat application. When photocuring and thermosetting are used in combination, a cured product layer such as a resist pattern that is more excellent in heat resistance can be formed. The heating temperature for curing by applying heat is preferably 100 ° C. or higher, more preferably 120 ° C. or higher, preferably 250 ° C. or lower, more preferably 200 ° C. or lower.

  The light irradiation may be performed after drawing or may be performed simultaneously with drawing. For example, light may be irradiated at the same time as or after the ejection of the curable composition. Thus, in order to irradiate light simultaneously with drawing, the light source may be arranged so that the light irradiation portion is positioned at the drawing position by the inkjet head.

  The light source for irradiating light is suitably selected according to the light to irradiate. Examples of the light source include a UV-LED, a low pressure mercury lamp, a medium pressure mercury lamp, a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a xenon lamp, and a metal halide lamp. The irradiated light is generally ultraviolet rays, and may be an electron beam, α-ray, β-ray, γ-ray, X-ray, neutron beam, or the like.

  The temperature at the time of application | coating of the curable composition for inkjets will not be specifically limited if it is the temperature from which the curable composition for inkjets becomes the viscosity which can be discharged from an inkjet head. The temperature at the time of application of the curable composition for inkjet is preferably 50 ° C. or higher, more preferably 60 ° C. or higher, and preferably 100 ° C. or lower. The viscosity of the curable composition for inkjet at the time of coating is not particularly limited as long as it can be discharged from the inkjet head.

  There is also a method of cooling the substrate during printing. When the substrate is cooled, the viscosity of the curable composition is increased at the time of landing and the resolution is improved. At this time, it is preferable to keep the cooling to such an extent that no condensation occurs or to dehumidify the air in the atmosphere so as not to cause condensation. Further, since the substrate contracts by cooling, the dimensional accuracy may be corrected.

  Since the curable composition for inkjet according to the present invention includes a specific reaction viscous material as the curing agent (D), for example, even when the inkjet curable composition is heated in an inkjet head, the inkjet curable composition is used. The pot life of the curable composition is sufficiently long and stable ejection is possible. Furthermore, since the ink-jet curable composition can be heated to a viscosity suitable for coating by the ink-jet method, the use of the ink-jet curable composition according to the present invention suitably produces electronic components such as printed wiring boards. can do.

  Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The present invention is not limited only to the following examples.

(Synthesis Example 1)
In a three-necked flask equipped with a stirrer, a thermometer, and a dropping funnel, 50 g of methyl cellosolve, 15 g of dicyandiamide, and 2,4-diamino-6- [2′-undecylimidazolyl- (1 ′)]-ethyl-s -1 g of triazine was added and heated to 100 ° C to dissolve dicyandiamide. After dissolution, 130 g of butyl glycidyl ether was added dropwise from the dropping funnel over 20 minutes and reacted for 1 hour. Thereafter, the temperature was lowered to 60 ° C., and the solvent was removed under reduced pressure to obtain a yellow and translucent reaction viscous product. The resulting reaction viscous product did not contain a solvent.

(Synthesis Example 2)
In a three-necked flask equipped with a stirrer, a thermometer, and a dropping funnel, 50 g of methyl cellosolve, 15 g of dicyandiamide, and 2,4-diamino-6- [2′-undecylimidazolyl- (1 ′)]-ethyl-s -1 g of triazine was added and heated to 100 ° C to dissolve dicyandiamide. After dissolution, 40 g of orthocresyl glycidyl ether was added dropwise from the dropping funnel over 20 minutes and reacted for 1 hour. Thereafter, the temperature was lowered to 60 ° C., and the solvent was removed under reduced pressure to obtain a yellow and translucent reaction viscous product. The resulting reaction viscous product did not contain a solvent.

(Synthesis Example 3)
A yellow and translucent reaction viscous product was obtained in the same manner as in Synthesis Example 2 except that the dripping amount of orthocresyl glycidyl ether was changed from 40 g to 95 g. The resulting reaction viscous product did not contain a solvent.

In addition, the following photopolymerization initiator was prepared.
Irgacure 907 (manufactured by BASF Japan): α-aminoalkylphenone type photoradical polymerization initiator having no dimethylamino group Irgacure 369 (manufactured by BASF Japan): α-aminoalkylphenone type photoradical polymerization having dimethylamino group Initiator Irgacure 379EG (manufactured by BASF Japan): α-aminoalkylphenone type photoradical polymerization initiator having a dimethylamino group TPO (manufactured by BASF Japan): acylphosphine oxide type photoradical polymerization initiator Irgacure 184 (BASF Japan) Manufactured by: α-hydroxyalkylphenone type photo radical polymerization initiator

Example 1
80 parts by weight of trimethylolpropane triacrylate (“TMPTA” manufactured by Daicel Cytec Co., Ltd.) corresponding to the polyfunctional compound (A) and an α-aminoacetophenone type photoradical polymerization initiator (BASF) corresponding to the photopolymerization initiator (B) 5 parts by weight of “Irgacure 907” manufactured by Japan, 20 parts by weight of a bisphenol A type epoxy resin (“YD-127” manufactured by Nippon Steel Chemical Co., Ltd.) corresponding to the compound (C) having a cyclic ether group, and a synthesis example 4 parts by weight of the reaction viscous product obtained in 1 was mixed to obtain a curable composition for inkjet.

(Example 2)
50 parts by weight of a bisphenol F type epoxy resin (“YD-170” manufactured by Nippon Steel Chemical Co., Ltd.) corresponding to the compound (C) having a cyclic ether group, and neopentyl glycol corresponding to the compound (C) having a cyclic ether group 50 parts by weight of diglycidyl ether (“EX-211” manufactured by Nagase ChemteX Corporation) and 30 parts by weight of the reaction viscous product obtained in Synthesis Example 2 were mixed to obtain a curable composition for inkjet.

(Examples 3 to 16 and Comparative Examples 1 to 5)
A curable composition for inkjet was obtained in the same manner as in Example 1 except that the types and blending amounts of the blending components were changed as shown in Tables 1 to 3 below.

  In addition, in the curable composition for inkjets obtained in Examples 1 to 16, the reaction viscous material is compatible with the polyfunctional compound and is compatible with the compound having a cyclic ether group, Further, it was dissolved in the curable composition.

(Evaluation of Examples 1-16 and Comparative Examples 1-5)
(1) Viscosity Based on JIS K2283, the viscosity at 25 degreeC of the obtained curable composition for inkjets was measured using the viscometer ("TVE22L" by the Toki Sangyo company). The viscosity of the curable composition for inkjet was determined according to the following criteria.

[Criteria for viscosity]
A: Viscosity exceeds 1200 mPa · s B: Viscosity exceeds 1000 mPa · s C: Viscosity exceeds 500 mPa · s, 1000 mPa · s or less D: Viscosity is 160 mPa · s or more, 500 mPa · s or less E: Viscosity is less than 160 mPa · s

(2) Inkjet ejection property The ejection test of the obtained curable composition for inkjet was performed from the inkjet head of a piezo-type inkjet printer with an ultraviolet irradiation device, and evaluated according to the following criteria. The head temperature was set to 80 ° C. during the discharge test of the curable composition having a viscosity of 500 mPa · s or less, and the head temperature was set to 95 ° C. during the discharge test of the curable composition having a viscosity exceeding 500 mPa · s.

[Judgment criteria for ink jetting properties]
◯: The curable composition could be continuously discharged from the head for 10 hours or longer. ○: The curable composition could be discharged from the head continuously for 10 hours or longer, but during the continuous discharge of 10 hours. Slight ejection unevenness occurs Δ: The curable composition can be continuously ejected from the head, but cannot be ejected continuously for more than 10 hours. X The curable composition is ejected from the head at the initial stage of ejection. Was impossible

(3) Wetting and spreading An FR-4 substrate with copper foil having a copper foil attached to the upper surface was prepared. An ink-jet curable composition is coated on the substrate so as to cover the entire surface of the copper foil so that the line width is 80 μm and the line-to-line spacing is 80 μm from the ink-jet head of a piezo-type ink-jet printer with an ultraviolet irradiation device. It was discharged and applied to draw a pattern. In the ejection test of the curable composition for ink jet having a viscosity of 500 mPa · s or less, the head temperature is set to 80 ° C., and in the ejection test of the curable composition for ink jet having a viscosity exceeding 500 mPa · s, the head temperature is set to 95 ° C. C.

The curable composition for inkjet (thickness 20 μm) coated on the substrate was irradiated with ultraviolet rays having a wavelength of 365 nm so that the irradiation energy was 1000 mJ / cm ² .

  Five minutes after irradiation with ultraviolet rays, the wet spread of the pattern was visually observed, and the wet spread was determined according to the following criteria.

[Wetting and spreading criteria]
○○: Wet spread state is the target line width + 40 μm or less ○: Wet spread state exceeds the target line width + 40 μm and 75 μm or less ×: The composition layer is wet spread from the drawing portion, and between the lines The interval is lost or the wet spread condition exceeds the target line width +75 μm.

(4) Storage stability (pot life length)
The obtained inkjet curable composition was filtered using a 5 μm membrane filter, and the filtered inkjet curable composition was heated at 80 ° C. for 12 hours.

  The FR-4 board | substrate with copper foil with which copper foil was affixed on the upper surface was prepared. On the copper foil on the substrate, the ink-jet curable composition was applied from the ink-jet head of a piezo-type ink-jet printer with an ultraviolet irradiation device so that the line width was 80 μm and the line-to-line spacing was 80 μm. I tried to draw a pattern. From the ejection properties from the inkjet head at this time, the storage stability was determined according to the following criteria. The head temperature was set to 80 ° C. during the discharge test of the curable composition having a viscosity of 500 mPa · s or less, and the head temperature was set to 95 ° C. during the discharge test of the curable composition having a viscosity exceeding 500 mPa · s.

[Criteria for storage stability]
○: The composition could be ejected from the inkjet head. X: The composition was cured before ejection, or the viscosity of the composition was increased, and the composition could not be ejected from the inkjet head.

(5) Heat resistance The FR-4 board | substrate with copper foil in which the copper foil was affixed on the upper surface was prepared. On the copper foil on the substrate, the ink-jet curable composition was applied from the ink-jet head of a piezo-type ink-jet printer with an ultraviolet irradiation device so that the line width was 80 μm and the line-to-line spacing was 80 μm. , Drawn in a pattern. The head temperature was set to 80 ° C. during the discharge test of the curable composition having a viscosity of 500 mPa · s or less, and the head temperature was set to 95 ° C. during the discharge test of the curable composition having a viscosity exceeding 500 mPa · s.

The curable composition for inkjet (thickness 20 μm) drawn in a pattern was irradiated with ultraviolet rays having a wavelength of 365 nm so that the irradiation energy was 1000 mJ / cm ² to obtain a primary cured product. Next, the primary cured product was heated at 150 ° C. for 60 minutes to be fully cured to obtain a resist pattern as a cured product.

  The obtained laminate of the substrate and the resist pattern was heated in an oven at 270 ° C. for 5 minutes, and then the appearance of the heated resist pattern was visually inspected. Further, a cellophane tape was attached to the resist pattern after heating, and the cellophane tape was peeled off in the 90-degree direction. The heat resistance was determined by the following criteria based on the appearance inspection and the peel test.

[Criteria for heat resistance]
○: There was no change in the resist pattern before and after heating in the appearance inspection, and the resist pattern did not peel from the substrate in the peeling test. ×: There was at least one of crack, peeling, and swelling in the resist pattern in the appearance inspection. Or the resist pattern peeled off from the substrate in the peel test

(6) Insulation reliability (migration resistance)
An IPC-B-25 comb test pattern B was prepared. The comb-type test pattern B is heated to 80 ° C., and the curable composition for inkjet is discharged from the inkjet head of the piezo-type inkjet printer with an ultraviolet irradiation device so as to cover the entire surface of the comb-type test pattern B. And coated. The head temperature was set to 80 ° C. during the discharge test of the curable composition having a viscosity of 500 mPa · s or less, and the head temperature was set to 95 ° C. during the discharge test of the curable composition having a viscosity exceeding 500 mPa · s.

The coated curable composition for inkjet (thickness 20 μm) was irradiated with ultraviolet rays having a wavelength of 365 nm so that the irradiation energy was 1000 mJ / cm ² to obtain a primary cured product. Next, the primary cured product was heated at 150 ° C. for 60 minutes to be fully cured to form a resist pattern as a cured product, thereby obtaining a test piece.

The obtained test piece was subjected to a humidification test for 500 hours under the conditions of applying 85 ° C., 85% relative humidity and 50V direct current. The insulation resistance after the humidification test was measured.
The results are shown in Tables 1 to 3 below. In Tables 1 to 3 below, “−” indicates that evaluation is not performed. In addition, except the evaluation of storage stability, the curable composition for inkjet which was not heated at 80 degreeC for 12 hours was used. In Table 3 below, * 1 indicates that the insulation resistance is 1 × 10 ⁹ or more and less than 3 × 10 ¹⁰ .

  In the curable compositions of Examples 1 to 14 using the α-aminoacetophenone type photopolymerization initiator, the photopolymerization initiators of Examples 15 and 16 using a photopolymerization initiator other than the α-aminoacetophenone type photopolymerization initiator were used. Compared to the curable composition, there is less stickiness of the surface of the primary cured product after light irradiation and before thermal curing, it is excellent in thermal curability during thermal curing, and the insulation reliability evaluation results are also good. It was.

  In Examples 17 to 40, materials shown in Table 4 below were appropriately used.

(Example 17)
65 parts by weight of tricyclodecane dimethanol diacrylate corresponding to the polyfunctional compound (A), 30 parts by weight of isobornyl acrylate corresponding to the monofunctional compound (E), and Irgacure corresponding to the photopolymerization initiator (B) 907 (α-aminoacetophenone type photo radical polymerization initiator, manufactured by BASF Japan Ltd.) 5 parts by weight was mixed to obtain a curable composition for inkjet.

(Examples 18 to 40)
A curable composition for inkjet was obtained in the same manner as in Example 17 except that the types and blending amounts of the blending components were changed as shown in Tables 5 and 6 below.

  In addition, in the curable composition for inkjets obtained in Examples 17 to 40, the reaction viscous material is compatible with the polyfunctional compound, is compatible with the monofunctional compound, and is a cyclic ether group. And was dissolved in the curable composition.

(Evaluation of Examples 17 to 40)
About Examples 17-40, it evaluated similarly about the evaluation items similar to Examples 1-16 and Comparative Examples 1-5. However, regarding the evaluation of insulation reliability (migration resistance), the insulation resistance was determined according to the following criteria, and the results are shown in Tables 5 and 6 below.

[Criteria for insulation reliability]
○: Insulation resistance is 3 × 10 ¹⁰ Ω or more Δ: Insulation resistance is 1 × 10 ⁹ or more and less than 3 × 10 ¹⁰ ×: Insulation resistance is less than 1 × 10 ⁹

  Furthermore, in Examples 17 to 40, the following wet heat resistance was also evaluated.

(7) Heat and humidity resistance (heat resistance and moisture resistance)
A glass epoxy substrate (100 mm × 100 mm) provided with copper wiring on the upper surface was prepared. On this board | substrate, the curable composition for inkjet was discharged from the inkjet head of the piezo-type inkjet printer with an ultraviolet irradiation device, and was coated on the whole surface. The head temperature was set to 80 ° C. during the discharge test of the curable composition having a viscosity of 500 mPa · s or less, and the head temperature was set to 95 ° C. during the discharge test of the curable composition having a viscosity exceeding 500 mPa · s.

The curable composition for inkjet (thickness 20 μm) coated on the substrate is irradiated with ultraviolet light having a wavelength of 365 nm so that the irradiation energy is 1000 mJ / cm ^2, and then heated at 180 ° C. for 1 hour to obtain a cured product. (Thickness 20 μm) was obtained.

  The obtained laminate of the substrate and the cured product was allowed to stand for 24 hours under conditions of 130 ° C. and a relative humidity of 85% RH. Then, the adhesiveness with respect to the board | substrate of hardened | cured material was confirmed by the crosscut tape test (JIS5400 6.15), and the heat-and-moisture resistance was determined with the following criteria. Make a cut of 100 squares at 1 mm intervals with a cutter on the cured product, and then apply cellophane tape (JIS Z1522) to the cured product with the cut part at an angle of 45 degrees. And peeled off strongly to confirm the peeled state.

[Criteria for wet heat resistance]
○○: No peeling of the cured product when peeling the tape ○: Part of the cured product is peeled when peeling the tape △: All of the cured product is peeled when peeling the tape ×: The cured product is peeled before peeling the tape doing

  The results are shown in Tables 5 and 6 below.

Claims (14)

A curable composition for inkjet that is applied by an inkjet method and is curable by application of heat,
A compound having an epoxy group;
A curing agent,
Wherein the curing agent, dicyandiamide, which is a reaction viscous obtained by reacting an epoxy group-containing compound having an epoxy group capable of reacting with the dicyandiamide, inkjet curable composition. The epoxy group-containing compound to be reacted with the dicyandiamide and 1 have a epoxy group, an inkjet curable composition according to claim 1. The curable composition for inkjet according to claim 1 or 2 , wherein the epoxy group-containing compound reacted with the dicyandiamide has an aromatic skeleton. The reaction viscous substance according to any one of claims 1 to 3 , wherein the reaction viscous substance is a reaction viscous substance obtained by reacting the epoxy group-containing compound with 1 mol or more and 3 mol or less with respect to 1 mol of dicyandiamide. Curable composition for inkjet. The curable composition for inkjet according to any one of claims 1 to 4 , wherein the dicyandiamide reacted with the epoxy group-containing compound is in a powder form. The curable composition for inkjet according to any one of claims 1 to 5 , wherein the reaction viscous material is dissolved in the curable composition. A curable composition for inkjet which is applied by an inkjet method and is curable by light irradiation and heat application,
A polyfunctional compound having two or more (meth) acryloyl groups;
The curable composition for inkjet according to any one of claims 1 to 6 , further comprising a photopolymerization initiator. The curable composition for inkjet according to claim 7 , wherein the photopolymerization initiator is an α-aminoalkylphenone type photoradical polymerization initiator. The curable composition for inkjet according to claim 7 , wherein the photopolymerization initiator is an α-aminoalkylphenone type photoradical polymerization initiator having a dimethylamino group. The ink jet curing according to any one of claims 1 to 9 , wherein the reaction viscous product is a reaction product obtained by reacting the epoxy group of the epoxy group-containing compound with a part of active hydrogen of dicyandiamide. Sex composition. The curable composition for inkjet according to any one of claims 1 to 10 , wherein a viscosity at 25 ° C measured in accordance with JIS K2283 is 160 mPa · s or more and 1200 mPa · s or less. Applying the curable composition for inkjet according to any one of claims 1 to 11 by an inkjet method, and drawing in a pattern;
A process for producing an electronic component, comprising: applying heat to the curable composition for inkjet drawn in a pattern and curing the composition to form a cured product layer. A method for manufacturing a printed wiring board, which is an electronic component having a resist pattern,
The ink-jet curable composition is applied by an ink-jet method, drawn in a pattern, and heat is applied to the ink-jet curable composition drawn in a pattern to be cured to form a resist pattern. The method of manufacturing an electronic component according to claim 12 . As the inkjet curable composition, an inkjet curable composition containing a polyfunctional compound having two or more (meth) acryloyl groups and a photopolymerization initiator,
In the step of forming the hardened material layer, the irradiation and heat with light applied to the inkjet curable composition drawn in a pattern and cured to form a cured product layer, in claim 12 or 13 The manufacturing method of the electronic component of description.