WO2022114133A1

WO2022114133A1 - Curable composition, cured product, and electronic component

Info

Publication number: WO2022114133A1
Application number: PCT/JP2021/043408
Authority: WO
Inventors: 悠斗小田桐; 秀之伊藤; 一善米田
Original assignee: 太陽インキ製造株式会社
Priority date: 2020-11-30
Filing date: 2021-11-26
Publication date: 2022-06-02
Also published as: CN116547326A; JPWO2022114133A1

Abstract

[Problem] To provide a curable composition having suitable flexibility, suitably low warpage after light exposure, as well as suitable heat resistance for a thin film substrate such as a flexible wiring board. [Solution] A curable composition containing: (A) a radical polymerizable monomer represented by formula 1 (R1 in formula (1) represents a C1-4 hydrocarbon group which may be linear, branched, or cyclic and may include an ether bond (the hydrocarbon group may have a substituent)); (B) a photocurable urethane compound having two (meth)acryloyl groups; (C) a compound other than (A) and (B) having a (meth)acryloyl group; (D) a photopolymerization initiator; and (E) a thermosetting component. The curable composition has low viscosity, and after being coated on a thin film substrate and exposed to light, is capable of keeping warpage of the thin film substrate low. Furthermore, the cured coated film has excellent heat resistance and has both flexibility and low warpage.

Description

Curable compositions, cured products and electronic components

The present invention relates to a curable composition, a cured product and an electronic component, and more particularly to a curable composition suitable for inkjet printing, the cured product thereof and an electronic component having the cured product thereof.

Since a flexible wiring board (FPC) is mounted on an electronic device, there is a demand for flexibility and heat resistance, and therefore, a solder resist for this FPC application is also required to have flexibility and heat resistance.

On the other hand, unlike a developing solder resist composition, a photocurable composition that can be applied onto a circuit board by inkjet printing is also required from the viewpoint of shortening the manufacturing process of electronic components. After applying such a photocurable composition to a polyimide substrate having a circuit and exposing it to light, the substrate tends to warp. If the substrate is warped in this way, there is a possibility that the photocurable composition cannot be applied to an appropriate position when the second layer is applied (overcoating). Further, if the substrate is warped, it may come into contact with the inkjet head. After that, when the coating film is thermally cured, the substrate is further warped. Therefore, it is necessary to suppress the warp of the photocurable composition for inkjet printing after exposure.

As such a composition for inkjet printing, for example, Patent Document 1 discloses a transparent resin composition for forming an insulating film used for inkjet printing, which has excellent bending resistance and coating film strength.

Japanese Unexamined Patent Publication No. 2013-189532

However, although the cured product of the resin composition of Patent Document 1 is disclosed to have excellent bending resistance, this inkjet ink is applied onto a thin film substrate such as a particularly thin polyimide (Kapton 100H). It has not been examined whether or not the warp after exposure is improved and whether or not it has sufficient heat resistance, and no measures for achieving both of these characteristics have been presented.

The present invention has been made in view of the above problems, and provides a curable composition having flexibility suitable for a thin film substrate such as a flexible wiring board, low warpage after exposure, and heat resistance. The purpose.

The present inventors have made diligent studies to achieve the above object. As a result, in the composition containing the photocurable compound, the photopolymerization initiator, and the thermosetting component, the light having two (meth) acryloyl groups and the compound represented by the following general formula (1) as the photocurable compound. It has been found that by containing a curable urethane compound, a curable composition having low warpage, flexibility and heat resistance of the coated substrate after exposure can be obtained, and the present invention has been completed.

That is, the object of the present invention is
(A) Equation (1)

(In the formula (1), R ¹ may be linear, branched or cyclic, and represents a hydrocarbon group having 1 or more and 4 or less carbon atoms which may contain an ether bond (provided that the hydrocarbon group has 1 or more and 4 or less carbon atoms). The hydrocarbon group may have a substituent)))
The radically polymerizable monomer represented by
(B) A photocurable urethane compound having two (meth) acryloyl groups and
(C) Compounds having (meth) acryloyl groups other than (A) and (B), and
(D) Photopolymerization initiator and
(E) Thermosetting component and
It was found to be achieved by a curable composition characterized by containing.

Further, it is preferable to further contain (F) a flame retardant, and the compounding amount of the photocurable urethane compound having two (B) (meth) acryloyl groups with respect to (F) the flame retardant is 1% by mass or more and 70% by mass or less. It is preferable to have

Further, when the mixing ratio of the radically polymerizable monomer represented by the formula (1) to the photocurable urethane compound having two (B) (meth) acryloyl groups is 250% by mass or more and 10,000% by mass or less. It is preferable to have.

Further, it is preferable that the mixing ratio of the radically polymerizable monomer represented by the formula (A) to the flame retardant (F) is 50% by mass or more and 350% by mass or less.

Moreover, it is preferable that the (E) thermosetting component contains a latent thermosetting component, and it is further preferable that the latent thermosetting component is a blocked isocyanate compound.

Further, it is preferable that the (F) flame retardant is a phosphorus-based flame retardant, and it is further preferable that the phosphorus-based flame retardant is phenoxyphosphazene.

Further, it is preferable that the curable composition has a viscosity of 50 mPa · s or less at 50 ° C.

Further, the above object of the present invention can also be achieved by a cured product obtained from the curable composition of the present invention and an electronic component having the cured product.

The curable composition of the present invention has a low viscosity and can suppress the warp of the thin film substrate after being applied to and exposed to the thin film substrate to a low level. Further, the cured coating film has excellent heat resistance, and has both low warpage and flexibility.

It is explanatory drawing of the MIT test performed on the cured film obtained from the curable composition.

<Curable composition>
The curable composition of the present invention is
(A) Equation (1)

(In the formula (1), R ¹ may be linear, branched or cyclic, and represents a hydrocarbon group having 1 or more and 4 or less carbon atoms which may contain an ether bond (provided that the hydrocarbon group has 1 or more and 4 or less carbon atoms). The hydrocarbon group may have a substituent)))
The radically polymerizable monomer represented by (hereinafter, also referred to as the radically polymerizable monomer of the formula (A) (1)) and
(B) A photocurable urethane compound having two (meth) acryloyl groups and
(C) Compounds having (meth) acryloyl groups other than (A) and (B), and
(D) Photopolymerization initiator and
(E) Thermosetting component and
It is a curable composition containing.

[Radical polymerizable monomer of formula (1) (A)]
The radically polymerizable monomer of the formula (A) (1) contained in the curable composition of the present invention is, for example, the following formula a):.

In (formula a), R ¹ is the same as R ¹ in formula (1), and X · indicates an initiator radical or a growth radical), so that the polymerization reaction proceeds while cyclizing. It is possible to form a main clavicle with a 5-membered ring ether structure having methylene radicals arranged on both sides as a repeating unit.

Examples of the hydrocarbon group having 1 or more and 4 or less carbon atoms include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group and a vinyl group. Examples thereof include an allyl group, a metalyl group, a crotyl group, a cyclopropyl group, a cyclobutyl group, a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group and a vinyloxyethyl group.

Examples of the substituent include a chain unsaturated hydrocarbon group such as a vinyl group, an allyl group, a metallicyl group and a crotyl group; an alkoxy group such as a methoxy group, an ethoxy group and a methoxyethoxy group; a methylthio group and an ethylthio group. Alkylthio group; acyl group such as acetyl group and propionyl group; acyloxy group such as acetyloxy group and propionyloxy group; alkoxycarbonyl group such as methoxycarbonyl group and ethoxycarbonyl group; alkylthio such as methylthiocarbonyl group and ethylthiocarbonyl group Examples thereof include a carbonyl group; a halogen atom such as a fluorine atom, a chlorine atom, a bromine atom and an iodine atom; a ureido group; an amide group; a cyano group; a hydroxyl group; and a trimethylsilyl group.

R ¹ reduces the viscosity of the radically polymerizable monomer of the formula (A) (1) and the viscosity of the radically polymerizable monomer of the formula (A) (1), thereby lowering the viscosity of the curable composition. From the viewpoint, a chain saturated hydrocarbon group having 1 to 4 carbon atoms, a chain unsaturated hydrocarbon group having 1 to 4 carbon atoms and a hydrocarbon having an ether bond having 1 to 4 carbon atoms. A hydrogen group is preferable, and a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, a tert-butyl group, an allyl group, a metalyl group, a crotyl group, a methoxyethyl group and an ethoxyethyl group. , And vinyloxyethyl groups are more preferable, and chains having 1 or more and 4 or less carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec-butyl group, and tert-butyl group. Saturated hydrocarbon groups are even more preferred, methyl, ethyl, n-propyl, isopropyl and tert-butyl groups are even more preferred, and methyl and ethyl groups are particularly preferred.

Examples of the radically polymerizable monomer of the formula (A) (1) include methyl α-allyloxymethylacrylate, ethyl α-allyloxymethylacrylate, n-propyl α-allyloxymethylacrylate, and α-allyloxy. Isopropyl methylacrylate, n-butyl α-allyloxymethylacrylate, sec-butyl α-allyloxymethylacrylate, tert-butyl α-allyloxymethylacrylate, vinyl α-allyloxymethylacrylate, α-allyl Allyl oxymethyl acrylate, metharyl α-allyl oxymethyl acrylate, crotyl α-allyl oxymethyl acrylate, methoxymethyl α-allyl oxymethyl acrylate, methoxy ethyl α-allyl oxymethyl acrylate, α-allyl oxymethyl acrylic Examples thereof include methoxypropyl acid, methoxybutyl α-allyloxymethylacrylate, ethoxymethylα-allyloxymethylacrylate, ethoxyethyl α-allyloxymethylacrylate, and vinyloxyethyl α-allyloxymethylacrylate. These may be used alone or in combination of two or more.

Among them, methyl α-allyl oxymethyl acrylate, ethyl α-allyl oxymethyl acrylate, n-propyl α-allyl oxymethyl acrylate, isopropyl α-allyl oxymethyl acrylate, n-butyl α-allyl oxymethyl acrylate. , Α-allyl oxymethyl acrylate sec-butyl, α-allyl oxymethyl acrylate tert-butyl, α-allyl oxymethyl acrylate allyl, α-allyl oxymethyl acrylate methallyl, α-allyl oxymethyl acrylate crotyl, methoxyethyl α-allyl oxymethyl acrylate, ethoxyethyl α-allyl oxymethyl acrylate, glycidyl α-allyl oxymethyl acrylate, vinyl oxyethyl α-allyl oxymethyl acrylate are preferable, and more preferably α-allyl oxymethyl. Methyl acrylate, ethyl α-allyl oxymethyl acrylate, n-propyl α-allyl oxymethyl acrylate, isopropyl α-allyl oxymethyl acrylate, n-butyl α-allyl oxymethyl acrylate, α-allyl oxymethyl acrylic Sect-butyl acid and tert-butyl α-allyloxymethylacrylate are preferred, with methyl α-allyloxymethylacrylate, ethyl α-allyloxymethylacrylate, n-propyl α-allyloxymethylacrylate, and α-allyl. Isopropyl oxymethyl acrylate and tert-butyl α-allyl oxymethyl acrylate are more preferred, and methyl α-allyl oxymethyl acrylate and ethyl α-allyl oxymethyl acrylate are even more preferred.

The radically polymerizable monomer of the formula (A) (1) can be adjusted according to, for example, the methods described in JP-A-2014-040585, JP-A-2011-137123, and the like.

The mixing ratio of the radically polymerizable monomer of the formula (A) (1) is preferably 250% by mass or more and 10,000% by mass with respect to the photocurable urethane compound having two (meth) acryloyl groups described later (B). % Or less, and particularly preferably 300% by mass or more and 5000% by mass or less. Within the above range, the curable resin composition is excellent in low warpage after exposure while maintaining a low viscosity.

Further, the mixing ratio of the radically polymerizable monomer of the formula (A) (1) is preferably 50 with respect to the flame retardant (F) when the curable composition contains the flame retardant (F) described later. It is by mass% or more and 350% by mass or less, and particularly preferably 65% by mass or more and 250% by mass or less. Within the above range, the curable resin composition is excellent in low warpage and flame retardancy after exposure while maintaining a low viscosity.

[(B) (Meta) Photocurable urethane compound having two acryloyl groups]
The curable composition of the present invention contains (B) a photocurable urethane compound having two (meth) acryloyl groups. (B) The photocurable urethane compound having two (meth) acryloyl groups gives flexibility to the cured product of the curable composition of the present invention, and is applied to a thin film substrate and exposed to the substrate. Suppress warpage.

(B) As the photocurable urethane compound having two (meth) acryloyl groups, a photocurable urethane compound having two (meth) acryloyl groups and having one or less (meth) acryloyl groups was used. It has excellent properties such as heat resistance and flexibility compared to the case, and has lower warpage and flexibility after exposure compared to the case of using a photocurable urethane compound having 3 or more (meth) acryloyl groups. Excellent.

Further, from the viewpoint of suppressing the viscosity of the curable composition of the present invention to be low, the photocurable urethane compound having two (B) (meth) acryloyl groups has a viscosity of 20,000 mPa · s or less at 25 ° C. It is preferable, and it is particularly preferable that it is 15,000 mPa · s or less.

In the present invention, the viscosity is 100 rpm, 30 seconds value according to the viscosity measurement method using a 10 cone-plate type rotational viscometer of JIS Z8803: 2011, and a cone plate type viscosity using 1 ° 34'x R24 as a cone rotor. It is a value measured by a meter (TVE-33H, manufactured by Toki Sangyo Co., Ltd.).

Similarly, from the viewpoint of keeping the viscosity of the curable composition of the present invention low, the photocurable urethane compound having two (B) (meth) acryloyl groups has a weight average molecular weight (Mw) of 6,000 or less. It is preferably 2,000 or less, and particularly preferably 2,000 or less.

(B) Examples of the photocurable urethane compound having two (meth) acryloyl groups include UA-112P, UA-4200, UA-4400, UA-160TM, UA-122P, UA-W2, (above, new). Nakamura Chemical Industry Co., Ltd.), CN962, CN963, CN964, CN965, CN980, CN981, CN982, CN983, CN996, CN9001, CN9002, CN9788, CN9893, CN978, CN9782, CN9783 (all manufactured by Sartmer), M-1100, M-1200, M-1210, M-1310, M-1600 (manufactured by Toagosei Chemical Industry Co., Ltd.), UN-9000PEP, UN-9200A, UN-7600, UN-333, UN-1255, UN-6060PTM, UN- 6060P, UN-6200 (manufactured by Negami Kogyo Co., Ltd.), AH-600, AT-600 (manufactured by Kyoeisha Chemical Co., Ltd.), Ebekryl 280, Evekrill 284, Evekrill 8402, Evekrill 8411, Evekrill 8807, Evekril 9270 (Dysel Ornex) Made) and the like.

(B) The blending ratio of the photocurable urethane compound having two (meth) acryloyl groups is, for example, 0.1 to 30% by mass, preferably 0.5 to 20% by mass, based on the entire curable resin composition. Is.

(B) The compounding ratio of the photocurable urethane compound having two (meth) acryloyl groups is 1% by mass or more and 70% by mass or less with respect to (F) the flame retardant when (F) the flame retardant is contained. It is preferably 10% by mass or more and 50% by mass or less, and particularly preferably 10% by mass or more and 40% by mass or less.

[Compounds having (meth) acryloyl groups other than (C) (A) and (B)]
The curable composition of the present invention contains a compound having a (meth) acryloyl group other than (C), (A) and (B). (C) A compound having a (meth) acryloyl group other than (A) and (B) is a component that is cured after exposure and incorporated into a cured product. In addition, in this specification, a compound having a (meth) acryloyl group other than (C) (A) and (B) may be abbreviated as "a compound having a (C) (meth) acryloyl group".

(C) The compound having a (meth) acryloyl group has a (meth) acryloyl group as a photopolymerizable group. Here, the (meth) acryloyl group is a general term for an acryloyl group and a meta-acryloyl group.

(C) A compound having a (meth) acryloyl group has one or more (meth) acryloyl groups, and optionally has a functional group such as a hydroxyl group, an ether bond, a ketone, an aromatic ring, or a heterocycle, or a structural portion. May have. Hereinafter, compounds having a (C) (meth) acryloyl group that can be contained in the curable composition of the present invention will be exemplified, but the compound having a (C) (meth) acryloyl group is limited to this exemplified compound. It's not a thing.

(C1) A compound having one (meth) acryloyl group (C) A compound having a (meth) acryloyl group includes, for example, a compound having one (C1) (meth) acryloyl group. (C1) The compound having one (meth) acryloyl group preferably has, for example, a specific functional group (preferably a hydroxyl group) other than the (meth) acryloyl group. When the compound having one (C1) (meth) acryloyl group has the specific functional group, the compound having one (C1) (meth) acryloyl group is a cured product after exposure to the curable composition of the present invention. By incorporating into the cured product, the specific functional group can be introduced into the cured product. When the specific functional group is introduced into the cured product in this way, various physical properties of the cured product can be further improved.

The compound having one (C1) (meth) acryloyl group is more preferably a compound having a (meth) acryloyl group and a hydroxyl group, and the compound having a (meth) acryloyl group and a hydroxyl group is the curability of the present invention. When blended in the composition, the adhesion between the obtained cured film and the conductor and the substrate is improved.

Examples of the compound having a (meth) acryloyl group and a hydroxyl group include 2-hydroxy-3-acryloyloxypropyl (meth) acrylate, 2-hydroxy-3-phenoxyethyl (meth) acrylate, and 1,4-cyclohexanedimethanol mono (meth). Meta) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol monohydroxypenta (meth) acrylate, Examples thereof include 2-hydroxypropyl (meth) acrylate. Commercially available products include Aronix M-5700 (trade name manufactured by Toagosei Co., Ltd.), 4HBA, 2HEA, CHDMMA (above, trade name manufactured by Kyoeisha Chemical Co., Ltd.), BHEA, HPA, HEMA, HPMA (above, manufactured by Nippon Catalyst Co., Ltd.). Product name), light ester HO, light ester HOP, light ester HOA (above, product name manufactured by Kyoeisha Chemical Co., Ltd.) and the like. The compound having a (meth) acryloyl group and a hydroxyl group can be used alone or in combination of two or more.

Of these, especially 2-hydroxy-3-acryloyloxypropyl acrylate, 2-hydroxy-3-phenoxyethyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 1,4-cyclohexanedimethanol Monoacrylate is preferably used. Further, from the viewpoint of easiness of adjusting the viscosity, a compound having no aromatic ring is preferably used.

(C1) When a compound having one (meth) acryloyl group is blended in the curable composition of the present invention, the blending amount thereof is preferably 1 part by mass or more per 100 parts by mass of the curable composition of the present invention. It is 15 parts by mass or less, more preferably 1 part by mass or more and 10 parts by mass or less, and particularly preferably 2 parts by mass or more and 5 parts by mass or less. It was

(C2) Compound having two (meth) acryloyl groups The compound having (C) (meth) acryloyl group includes, for example, a compound having two (C2) (meth) acryloyl groups.

(C2) A compound having two (meth) acryloyl groups is preferably a photocurable diluent, that is, a curing composition that is diluted to contribute to a decrease in viscosity, and is cured after exposure to become a cured product. It is an ingredient to be incorporated.

(C2) When the compound having two (meth) acryloyl groups is a photocurable diluent, the viscosity at 50 ° C. is less than 50 mPa · s from the viewpoint of diluting the curable composition of the present invention to reduce the viscosity. The viscosity at 50 ° C. is preferably less than 30 mPa · s, and particularly preferably the viscosity at 50 ° C. is 15 mPa · s or less.

Examples of the compound having two (C2) (meth) acryloyl groups having a viscosity at 50 ° C. of less than 50 mPa · s include a bifunctional (meth) acryloyl group-containing monomer which is an ester of alkylene glycol and (meth) acrylic acid. Can be mentioned.

The alkylene glycol may be a monoalkylene glycol or one having a repeating structure of two or more alkylene glycols. Examples of the monoalkylene glycol include linear or branched alkylene diols having 3 to 16 carbon atoms, preferably 6 to 9 carbon atoms.

Examples of those having a repeating structure of two or more alkylene glycols include diethylene glycol, dipropylene glycol, dibutylene glycol, triethylene glycol, tripropylene glycol, and tributylene glycol.

Specifically, examples of the compound having two (C2) (meth) acryloyl groups having a viscosity at 50 ° C. of less than 50 mPa · s include diethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, and dibutylene glycol. Di (meth) acrylate, triethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate, tributylene glycol di (meth) acrylate, 1,3-butylene glycol di (meth) acrylate, 1,4-butane Examples thereof include diol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonane diol acrylate, 1,10-decane diol diacrylate, and 1,16-hexadecane diol diacrylate.

Commercially available products of compounds having two (C2) (meth) acryloyl groups having a viscosity at 50 ° C. of less than 50 mPa · s include 2G (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), 3G (manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), and DPGDA. (Manufactured by Daisel Ornex), T0948 (manufactured by Tokyo Kasei Kogyo Co., Ltd.), T2389 (manufactured by Tokyo Kasei Kogyo Co., Ltd.), Viscort # 310HP (manufactured by Osaka Organic Chemical Industry Co., Ltd.), PE-200 (Daiichi Kogyo Seiyaku Co., Ltd.) Company), PE-300 (Daiichi Kogyo Seiyaku Co., Ltd.), HDDA (Daisel Ornex Co., Ltd.), LC9A (Daiichi Kogyo Seiyaku Co., Ltd.), A-NOD-N (Shin-Nakamura Chemical Industry Co., Ltd.) , B1065 (manufactured by Tokyo Kasei Kogyo Co., Ltd.), 1,9-NDA (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and the like.

When a compound having two (C2) (meth) acryloyl groups having a viscosity at 50 ° C. of less than 50 mPa · s is blended in the curable composition of the present invention, the blending amount thereof is the curable composition 100 of the present invention. With respect to the mass part, for example, it is 2 parts by mass or more and 50 parts by mass or less, preferably 6 parts by mass or more and 40 parts by mass or less, and more preferably 10 parts by mass or more and 30 parts by mass or less.

The blending amount of the compound having two (C2) (meth) acryloyl groups having a viscosity of less than 50 mPa · s at 50 ° C. is 2 parts by mass or more and 50 parts by mass or less with respect to 100 parts by mass of the curable composition of the present invention. By doing so, the viscosity of the curable composition can be maintained at a low viscosity, and the compound having two (C2) (meth) acryloyl groups having a viscosity of less than 50 mPa · s at 50 ° C. after photocuring, that is, exposure can be used. It will be incorporated into the cured product.

(C3) A compound having no aromatic ring and having three or more (meth) acryloyl groups (C) A compound having a (meth) acryloyl group is, for example, a compound having no (C3) aromatic ring and having (meth) acryloyl. Contains compounds having 3 or more groups.

When the curable composition of the present invention contains a compound having (C3) no aromatic ring and having three or more (meth) acryloyl groups, the curable composition of the present invention is exposed while suppressing an increase in viscosity. The curability of time is further improved.

(C3) Examples of the compound having no aromatic ring and having three or more (meth) acryloyl groups include trimethylolpropane triacrylate, trimethylolmethane triacrylate, ethylene oxide-modified trimethylolpropane triacrylate, and propylene oxide-modified trimethylol. Propanetriacrylate, epichlorohydrin-modified trimethylolpropanetriacrylate, pentaerythritol tetraacrylate, tetramethylolmethanetetraacrylate, ethyleneoxide-modified phosphoric acid triacrylate, propyleneoxide-modified phosphate triacrylate, epichlorhydrin-modified glyceroltriacrylate, dipentaerythritol hexaacrylate , Ditrimethylolpropane tetraacrylate, polyfunctional acrylate typified by these silsesquioxane modified products, or the corresponding metal acrylate monomer, ε-caprolactone-modified trisacryloxyethyl isocyanurate.

The compound having three or more (meth) acryloyl groups may be a multi-branched oligomer or polymer. It was

(C3) When a compound having no aromatic ring and having three or more (meth) acryloyl groups is blended in the curable composition of the present invention, the blending amount thereof is 100 parts by mass of the curable composition of the present invention. It is preferably 1 part by mass or more and 40 parts by mass or less, and more preferably 5 parts by mass or more and 20 parts by mass or less.

(C4) A compound having an aromatic ring and having two or more (meth) acryloyl groups (C) A compound having a (meth) acryloyl group is, for example, having a (C4) aromatic ring and having a (meth) acryloyl group. Contains compounds having two or more.

When the curable composition of the present invention contains a compound having a (C4) aromatic ring and two or more (meth) acryloyl groups, the curability at the time of exposure is further improved, and the compound forms an aromatic ring. By having it, it contributes to further improvement of properties such as heat resistance and flame retardancy of the cured film (cured product). The compound having (C4) an aromatic ring and having two or more (meth) acryloyl groups has a relatively high viscosity because it contains an aromatic ring (that is, the viscosity at 50 ° C. is 50 mPa · s or more). Will be). Further, from the viewpoint of suppressing an increase in the viscosity of the curable composition while maintaining good photocurability, it is preferable that the number of (meth) acryloyl groups in one molecule of this compound is two.

Examples of the compound having a (C4) aromatic ring and two or more (meth) acryloyl groups include (meth) acrylate of a polyhydric phenol and an alkylene oxide adduct thereof.

Examples of the polyvalent phenol include bisphenol A, bisphenol AP, bisphenol B, bisphenol BP, bisphenol E, bisphenol F, bisphenol M, bisphenol P, bisphenol PH, bisphenol Z and other bisphenols, and biphenol.

Examples of the alkylene oxide include ethylene oxide, propylene oxide, and butylene oxide. The number of alkylene oxides added is preferably 6 or less.

(C4) Commercially available products of compounds having an aromatic ring and having two or more (meth) acryloyl groups include ABE-300 (manufactured by Shin Nakamura Chemical Industry Co., Ltd.), BPE-80N (manufactured by Shin Nakamura Chemical Industry Co., Ltd.), and the like. BPE-100 (manufactured by Shin Nakamura Chemical Industry Co., Ltd.), A-BPE-4 (manufactured by Shin Nakamura Chemical Industry Co., Ltd.), BPE-4 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), BPE-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) ), A-BPE-10 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), BPE-200 (manufactured by Shin Nakamura Chemical Industry Co., Ltd.), EBECRYL 150 (manufactured by Daicel Ornex Co., Ltd.) and the like.

(C4) When a compound having an aromatic ring and having two or more (meth) acryloyl groups is blended in the curable composition of the present invention, the blending amount thereof is 100 parts by mass of the curable composition of the present invention. On the other hand, it is preferably 1 part by mass or more and 40 parts by mass or less, and more preferably 5 parts by mass or more and 20 parts by mass or less.

The curable composition of the present invention preferably contains a compound having two (C2) (meth) acryloyl groups as a compound having (meth) acryloyl groups other than (C), (A) and (B). In particular, it is preferable to contain a compound having two (C2) (meth) acryloyl groups having a viscosity at 50 ° C. of less than 50 mPa · s.

[(D) Photopolymerization Initiator]
As the photopolymerization initiator, any compound that generates radicals by light, a laser, an electron beam, or the like and initiates a radical polymerization reaction can be used. Examples of the (D) photopolymerization initiator include benzoin and benzoin alkyl ethers such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2, Acetophenones such as 2-diethoxy-2-phenylacetophenone and 1,1-dichloroacetophenone; 2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropane-1-one, 2-benzyl-2- Aminoacetophenones such as dimethylamino-1- (4-morpholinophenyl) -butane-1-one, N, N-dimethylaminoacetophenone; 2-methylanthraquinone, 2-ethylanthraquinone, 2-t-butylanthraquinone, 1- Anthraquinones such as chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, 2,4-diisopropylthioxanthone; acetophenone dimethylketal, ketals such as benzyldimethylketal; 2 , 4,5-Triarylimidazole dimer; riboflavin tetrabutyrate; thiol compounds such as 2-mercaptobenzoimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole; 2,2,2-tribromoethanol, tri Organic halogen compounds such as bromomethylphenyl sulfone; benzophenone, benzophenones or xanthones such as 4,4'-bisdiethylaminobenzophenone; 2,4,6-trimethylbenzoyldiphenylphosphine oxide; 1,2-octanedione, 1-[ 4- (Phenylthio)-, 2- (O-benzoyloxime)], etanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazole-3-yl]-, 1- (O-) Examples thereof include oxime esters such as acetyl oxime).

The above (D) photopolymerization initiator can be used alone or in combination of two or more. In addition to these, light such as tertiary amines such as N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, and triethanolamine. Initiating aids can be used. Further, a titanosen compound of Omnirad 784 or the like (manufactured by IGM Resins B.V.), which has an absorption wavelength in the visible light region, can also be added as the (D) photopolymerization initiator in order to promote the photocuring reaction. The components to be added as the photopolymerization initiator are not limited to these, but those that absorb light in the ultraviolet light or visible light region to initiate radical polymerization of ethylenically unsaturated groups such as (meth) acryloyl groups. However, it is not limited to the known photopolymerization initiators and photoinitiator aids, and can be used alone or in combination of two or more.

The blending amount of the photopolymerization initiator (D) is preferably 0.2 parts by mass or more and 15 parts by mass or less, and more preferably 1 part by mass or more and 8 parts by mass with respect to 100 parts by mass of the curable composition of the present invention. It is less than a part.

(D) Product names of commercially available photopolymerization initiators include, for example, Omnirad 907, Omnirad 127, Omnirad 379EG, Omnirad 379EG (all manufactured by IGM Resins BV) and the like.

[(E) Thermosetting component]
Further, the curable composition of the present invention contains (E) a thermosetting component. (E) By containing a thermosetting component, in addition to coating of a curable composition, low warpage of the substrate after exposure and flame retardancy of the cured film, functionality such as heat resistance and plating resistance of the cured film can be obtained. It can be further improved.

As the (E) thermosetting component, for example, a known compound such as a blocked isocyanate compound, an epoxy compound, or an oxetane compound can be used.

Among them, in the present invention, it is particularly preferable that the (E) thermosetting component contains a latent thermosetting component in which the functional group in the structure is protected by a protecting group. By including such a latent thermosetting component, it is possible to suppress an unintended reaction in the curable composition due to unforeseen conditions and enhance the storage stability of the curable composition. In addition, the curable composition is also excellent in inkjet printability at 50 ° C., and when a reaction is desired, it can be easily deprotected by heating or the like to activate the thermosetting component. In the present invention, the potential means a property that does not show activity at room temperature or a little heating condition, but is activated by heating at a high temperature of 80 ° C. or higher and shows thermosetting property.

Above all, it is preferable that the latent thermosetting component is a blocked isocyanate compound. The blocked isocyanate compound is preferably a compound having a plurality of blocked isocyanate groups in one molecule. The blocked isocyanate group is a group in which the isocyanate group is protected by the reaction with the blocking agent and is temporarily inactivated, and when heated to a predetermined temperature, the blocking agent is dissociated to generate an isocyanate group. do.

As the polyisocyanate compound having a plurality of isocyanate groups, for example, aromatic polyisocyanate, aliphatic polyisocyanate or alicyclic polyisocyanate is used.

Specific examples of the aromatic polyisocyanate include 4,4'-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, o-xylylene diisocyanate, and the like. Examples thereof include m-xylylene diisocyanate and 2,4-tolylene dimer.

Specific examples of the aliphatic polyisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, 4,4-methylene bis (cyclohexyl isocyanate) and isophorone diisocyanate.

Specific examples of the alicyclic polyisocyanate include bicycloheptane triisocyanate. In addition, the adduct form, the burette form, the isocyanurate form and the like of the isocyanate compounds mentioned above can be mentioned.

Examples of the isocyanate blocking agent include phenolic blocking agents such as phenol, cresol, xylenol, chlorophenol and ethylphenol; lactam blocking agents such as ε-caprolactam, δ-palerolactam, γ-butyrolactam and β-propiolactam; Active oxime-based blocking agents such as ethyl acetoacetate and acetylacetone; methanol, ethanol, propanol, butanol, amyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether, benzyl. Alcohol-based blocking agents such as ether, methyl glycolate, butyl glycolate, diacetone alcohol, methyl lactate and ethyl lactate; oxime-based blocking agents such as formaldehyde xim, acetoaldoxime, acetoxime, methylethylketoxim, diacetylmonooxime and cyclohexaneoxime. Mercaptan-based blocking agents such as butyl mercaptan, hexyl mercaptan, t-butyl mercaptan, thiophenol, methylthiophenol, ethylthiophenol; acid amide-based blocking agents such as acetate amide and benzamide; imides such as succinic acid imide and maleate imide. Oxime-based blocking agents; Amin-based blocking agents such as xylidine, aniline, butylamine, dibutylamine; Imidazole-based blocking agents such as imidazole and 2-ethylimidazole; Imine-based blocking agents such as methyleneimine and propyleneimine; Pyrazole-based such as dimethylpyrazole Examples include blocking agents.

The blocked isocyanate compound may be commercially available, for example, Duranate TPA-B80E, 17B-60PX, E402-B80T (all manufactured by Asahi Kasei Corporation), TrixeneBI7982: blocked isocyanate (hexamethylene isocyanate (HDM) trimer, Blocking agents: dimethylpyrazole (DMP), Baxenden Chemicals) and the like.

The latent thermosetting component may be a reaction product obtained by reacting an amine compound such as imidazole or dicyandiamide with a hydroxyl group-containing compound, a cyclic ether group-containing compound, a carboxyl group-containing compound, or the like.

The blending amount of the (E) thermosetting component is preferably 1 part by mass or more and 30 parts by mass or less, and more preferably 3 parts by mass or more and 15 parts by mass or less per 100 parts by mass of the curable composition of the present invention. (E) When the blending amount of the thermosetting component is 1 part by mass or more and 30 parts by mass or less per 100 parts by mass of the curable composition of the present invention, the storage stability of the curable composition of the present invention is maintained. , Functionality such as heat resistance and plating resistance of the cured film can be further improved.

[(F) Flame Retardant]
The curable composition of the present invention may contain a known and commonly used (F) flame retardant for the purpose of improving the flame retardancy of the obtained cured product. Further, by containing a flame retardant, the low warpage after exposure can be further improved.
(F) Examples of the flame retardant include phosphoric flame retardants such as phosphoric acid esters and condensed phosphoric acid esters, phosphorus-containing compounds having phenolic hydroxyl groups, phosphazenic compounds, and phosphinic acid metal salts, antimony trioxide, and antimony pentoxide. Examples thereof include antimony compounds such as, pentabromodiphenyl ether, halogen compounds such as octabromodiphenyl ether, metal hydroxides such as aluminum hydroxide and magnesium hydroxide, and layered compound hydroxides such as hydrotalcite. Phosphorus-based flame retardants are preferable because of their environmental impact and flame retardant effect.
Examples of the phosphinic acid metal salt include the following structural formula (2).

(In the formula (2), R ¹ and R ² represent an alkyl group having 1 to 6 carbon atoms or an aryl group having 12 or less carbon atoms, respectively, M represents calcium, aluminum or zinc, and M represents calcium, aluminum or zinc. When representing aluminum, m = 3, and when representing other metals, m = 2).
Those having a structure represented by are preferable.

More preferably, it is a compound having a structure in which M represents aluminum in the formula (2).

By using the phosphinic acid metal salt, the flame retardancy can be improved without impairing the flexibility of the cured film.

Specific examples of the phosphinic acid constituting the phosphinic acid metal salt include phosphinic acid, dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid, methyl-n-propylphosphinic acid, methanedi (methylphosphinic acid), benzene-1, Examples thereof include 4- (dimethylphosphinic acid), methylphenylphosphinic acid, phenylphosphinic acid, diphenylphosphinic acid and mixtures thereof.

Examples of commercially available products include Exolit OP 1240, 1240, 1312, 1400, 930, 945TP, and OP-935.

From the viewpoint of low warpage and flexibility after exposure, it is preferable to use a phosphazene compound as a phosphorus-based flame retardant. The phosphazene compound is preferably a phenoxyphosphazene having a phosphazene structure and a phenoxy group substituted with any one of a cyano group (-CN), a hydroxyl group (-OH) and a methyl group. In particular, it has a hexaphenoxycyclotriphosphazene structure as a basic skeleton, and at least two of the six phenoxy groups in the structure are substituted with a cyano group (-CN) or a hydroxyl group (-OH). preferable.

In a preferred embodiment, only one of the two phenoxy groups attached to the phosphorus atom in the hexaphenoxycyclotriphosphazene structure is substituted with one cyanide group (-CN) and thus substituted. It is a structure having two phenoxy groups as a whole hexaphenoxycyclotriphosphazene structure.

In yet another preferred embodiment, the two phenoxy groups attached to the phosphorus atom in the hexaphenoxycyclotriphosphazene structure are both substituted with one cyano group (-CN), and the phenoxy group thus substituted. Is a structure having all six hexaphenoxycyclotriphosphazene structures as a whole.

In yet another preferred embodiment, only one of the two phenoxy groups attached to the phosphorus atom in the hexaphenoxycyclotriphosphazene structure is substituted with one hydroxyl group (-OH) and thus thus. It is a structure having three substituted phenoxy groups as a whole hexaphenoxycyclotriphosphazene structure.

More preferably, the cyclic phosphazene compound has the following structure:

or

or

It has one of the structures.

Examples of the preferable commercially available phosphazene compound include FP-300B, FP-300, and SPH-100 (all manufactured by Fushimi Pharmaceutical Co., Ltd.).

(F) One type of flame retardant may be used alone, or two or more types may be used in combination.

The amount of the flame retardant (F) blended in the curable composition of the present invention is, for example, 5% by mass or more and 60% by mass or less, preferably 10% by mass or more and 50% by mass or less. (F) When the flame retardant is a phosphorus-based flame retardant, the blending amount of the phosphorus-based flame retardant is 0.1% by mass or more and 10% by mass or less as the phosphorus content in the curable composition of the present invention. It is possible to effectively impart flame retardancy while maintaining heat resistance and low warpage.

[Thermosetting catalyst selected from the group consisting of melamine and its derivatives]
The curable composition of the present invention preferably contains a thermosetting catalyst selected from the group consisting of melamine and its derivatives. Melamine and its derivatives act as a curing accelerator for thermosetting reactions, and are used to further improve properties such as heat resistance in addition to adhesion of the cured product to the conductor circuit.

Examples of the thermosetting catalyst selected from the group consisting of melamine and its derivatives include guanamines such as acetoguanamine and benzoguanamine; melamine; ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4. Examples thereof include triazine derivatives such as -diamino-6-xylyl-S-triazine, and melamine is preferable.

The thermosetting catalyst selected from the group consisting of melamine and its derivatives can be used alone or in combination of two or more. When the thermosetting catalyst selected from the group consisting of melamine and its derivatives is blended in the curable composition of the present invention, the blending amount thereof is (E) when the total amount of the thermosetting components is 100% by mass. It is preferably 0.1% by mass or more and 20% by mass or less, more preferably 0.5% by mass or more and 20% by mass or less, and particularly preferably 1% by mass or more and 15% by mass or less.

By setting the blending amount of the thermosetting catalyst selected from the group consisting of melamine and its derivatives to 0.1% by mass or more and 20% by mass or less when the total amount of (E) thermosetting components is 100% by mass. , Good thermosetting can be realized while improving the storage stability of the curable composition.

Additives such as antioxidants, antifoaming / leveling agents, thixotropy-imparting agents / thickeners, coupling agents, dispersants, polymerization retarders, and colorants are added to the curable composition of the present invention, if necessary. Can be contained.

Further, in the curable composition of the present invention, a solvent may be used for adjusting the viscosity, but it is preferable that the amount added is small in order to prevent the film thickness from being lowered after curing. Further, it is more preferable that the solvent for adjusting the viscosity is not contained.

The curable composition of the present invention is preferably applied to printing by an inkjet method. In order to make it applicable to printing by the inkjet method, it is preferable that the viscosity is such that it can be ejected by an inkjet printer.

The viscosity of the curable composition of the present invention is preferably 50 mPa · s or less at 50 ° C, more preferably 20 mPa · s or less at 50 ° C, and 15 mPa · s or less at 50 ° C. Is particularly preferable.

Therefore, the curable composition of the present invention can directly print a pattern on a substrate for a printed wiring board or the like by an inkjet printing method.

Furthermore, since the curable composition of the present invention does not undergo a polymerization reaction at room temperature, it can be stably stored as a one-component curable composition.

The curable composition of the present invention can be supplied as ink to an inkjet printer due to its low viscosity, and can be used for printing on a substrate. Further, since the warpage of the thin film substrate can be suppressed to a low level after printing on a thin film substrate such as a polyimide substrate and exposing it, it is suitable as a composition for solder resist for a flexible wiring board.

<Curing product obtained from the curable composition>
In the cured product obtained by the curable composition of the present invention, for example, the composition layer immediately after printing is photo-cured by irradiating the composition layer with an active energy ray of 50 mJ / cm ² to 1000 mJ / cm ² . Obtained at. The activation energy ray irradiation is performed by irradiation with active energy rays such as ultraviolet rays, electron beams, and chemical rays, preferably by ultraviolet irradiation.

Ultraviolet irradiation in an inkjet printer can be performed by, for example, attaching a light source such as a high-pressure mercury lamp, a metal halide lamp, or an ultraviolet LED to the side surface of the print head, and scanning by moving the print head or the substrate. In this case, printing and ultraviolet irradiation can be performed almost at the same time.

The cured product after photocuring is thermally cured by using a known heating means, for example, a heating furnace such as a hot air furnace, an electric furnace, or an infrared induction heating furnace. As the heating conditions, it is preferable to heat at 130 ° C to 170 ° C for 5 to 90 minutes.

The cured product obtained by the curable composition of the present invention is also excellent in flexibility, and is therefore particularly suitable as a solder resist for flexible wiring boards.

Examples of the substrate of the flexible wiring board include a film made of glass polyimide, polyimide, polyethylene terephthalate, liquid crystal polymer, polycarbonate, and the like.

<Electronic components with a cured product of a curable composition>
When a cured film made of a curable composition having a pattern printed on a substrate in this way is used as a solder resist, it is heated in a soldering step for mounting components. Soldering may be performed by hand soldering, flow soldering, reflow soldering, or the like. For example, in the case of reflow soldering, preheating at 100 ° C. to 140 ° C. for 1 to 4 hours is required. After that, it is subjected to a reflow process of heating and melting the solder by repeating heating at 240 to 280 ° C. for about 5 to 20 seconds multiple times (for example, 2 to 4 times). The parts are completed.

In the present invention, the electronic component means a component used in an electronic circuit, and includes active components such as printed wiring boards, transistors, light emitting diodes, and laser diodes, as well as passive components such as resistors, capacitors, inductors, and connectors. The cured product of the curable composition of the present invention exerts the effect of the present invention as these insulating cured films.

The curable composition of the present invention has a low viscosity, excellent coatability, and little warpage after photocuring. Further, it is flexible even after curing, and is excellent in adhesion to a substrate, flame retardancy, solder heat resistance, plating resistance, and solvent resistance, so that it can be applied to various applications, and there is no particular limitation on the application target. For example, it can be used for manufacturing etching resists, solder resists, marking inks, etc. of printed wiring boards by inkjet printing, and among them, solder on flexible wiring boards by inkjet printing, which requires low warpage and flame retardancy after exposure. It can be suitably used as a composition for forming a resist.

It can also be used as a material for UV molded products, a material for stereolithography, and a material for 3D inkjet.

The present invention is not limited to the configuration and examples of the above-described embodiment, and various modifications can be made within the scope of the gist of the invention.

Hereinafter, the present invention will be specifically described with reference to Examples, but the present invention is not limited to these Examples. In the following, unless otherwise specified, "parts" shall mean parts by mass.

<1. Preparation of Curable Compositions of Examples 1 to 18 and Comparative Examples 1 to 4>
Each component was mixed in the ratio (unit: parts by mass) shown in Table 1 below, and this was stirred with a dissolver. Then, dispersion was carried out with 1 mm zirconia beads using a bead mill for 2 hours to obtain a curable composition of the present invention (Examples 1 to 18) and a curable composition of Comparative Examples (Comparative Examples 1 to 4). ..

* 1: Α- (allyloxymethyl) methyl acrylate (AOMA: manufactured by Nippon Shokubai Co., Ltd.)
* 2: Bifunctional urethane acrylate, viscosity at 25 ° C: 2,000 mPa · s, Mw = 1,000 (UA-2000, manufactured by Shin Nakamura Chemical Industry Co., Ltd.)
* 3: Bifunctional urethane acrylate, viscosity at 25 ° C.: 12,500 mPa · s, Mw = 1,000 (Evecryl 8402, manufactured by Dycel Ornex)
* 4: Bifunctional urethane acrylate, viscosity at 25 ° C: 25,000 mPa · s, Mw = 6,500 (UN-6200, manufactured by Negami Kogyo Co., Ltd.)
* 5: Trifunctional urethane acrylate, viscosity at 25 ° C: 15,000 mPa · s (UA-7100, manufactured by Shin Nakamura Chemical Industry Co., Ltd.)
* 6: Hexfunctional urethane acrylate oligomer, viscosity at 25 ° C. 1,000-3,000 mPa · s (DM576, manufactured by DOUBLE BOND CHEMICAL)
* 7: Trimethylolpropane triacrylate (A-TMPT, manufactured by Shin Nakamura Chemical Industry Co., Ltd.)
* 8: 1,9-Nonanediol diacrylate (1,9-NDA, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.)
* 9: Dipropylene glycol diacrylate (DPGDA, manufactured by Dycel Ornex Co., Ltd.)
* 10: Ethoxylated bisphenol A diacrylate (A-BPE-10, manufactured by Shin Nakamura Chemical Industry Co., Ltd.)
* 11: 4-Hydroxybutyl acrylate (4HBA, manufactured by Nihon Kasei)
* 12: Trifunctional blocked isocyanate (BI7982, manufactured by Baxenden chemical)
* 13: Melamine (manufactured by Nissan Chemical Industries, Ltd.)
* 14: 2- (dimethylamino) -2-[(4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone (Omnirad 379, manufactured by IGM)
* 15: Phosphazene compound (phosphorus content 12.5%) (FP-300B, manufactured by Fushimi Pharmaceutical Co., Ltd.)
* 16: Metallic phosphinic acid salt (phosphorus content 23.0%) (OP935, manufactured by Clariant Chemicals, Inc.)
* 17: Aluminum hydroxide (H42M, manufactured by Showa Denko)
* 18: Phthalocyanine-based blue colorant (Pigment Blue15: 3)
* 19: Anthraquinone-based yellow colorant (Pigment Yellow147)

<2. Evaluation>
The viscosities of the curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 were evaluated as follows. In addition, as shown below, test samples were prepared and evaluated for coatability, post-exposure warpage, flexibility (MIT test), solder heat resistance, solvent resistance, electroless gold plating resistance and flame retardancy. rice field. The results are shown in Table 2.

(1) Viscosity With respect to the curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4, the viscosities at an ink temperature of 50 ° C. and 100 rpm were measured with a cone plate type viscometer (TVH-33H manufactured by Toki Sangyo Co., Ltd.). , Evaluated according to the following criteria.

⊚: 10 mPa · s or less ○: 10 mPa · s more than 20 mPa · s or less ×: 20 mPa · s more than

(2) Conditions for Forming a Cured Film The curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 were applied by an inkjet printing apparatus CPS6151 (manufactured by Microcraft). As the array, KM1024iSHE (manufactured by Microcraft Co., Ltd., coating droplet amount 6 pL, number of nozzles 2 × 1024, head temperature 50 ° C.) was used. Photocuring was performed at 300 mJ / cm ² using SGHUV-UN-L042-B (manufactured by Microcraft, LED light source, wavelength 365 nm) as a light source. After that, a hot air circulation type drying oven DF610 (manufactured by Yamato Kagaku Co., Ltd.) was used as a heating device, and the main curing was performed at 150 ° C. for 60 minutes.

(3) Coatability The curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 were sulfuric acid-treated with an inkjet printing device CPS6151 (manufactured by Microcraft Co., Ltd.) and Espanex (registered trademark) M (Nittetsu Chemical Co., Ltd.). & Material Co., Ltd.) was applied on the copper surface with a coating thickness of 20 μm. The surface of the coating film was visually observed and evaluated according to the following criteria.

◯: Uniform coating and smooth surface Δ: Full coating, but streaks in the head operation direction ×: Part of the coating film is missing What is

(4) Post-exposure warpage The curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 were treated with sulfuric acid under a photocuring condition of 800 mJ / cm ² using an inkjet printing device CPS6151 (manufactured by Microcraft). It was applied to one side of Kapton (registered trademark) 200H or 100H (manufactured by Toray DuPont). The obtained laminated body of the coated film after exposure was cut out into a sample (film thickness: 15 μm) in a size of 5 cm × 5 cm (length × width). After exposure, each sample was allowed to stand on a horizontal workbench for 30 minutes with the coating surface as the upper surface, and the heights of the four edges of the sample raised from the workbench were measured with a ruler, and the average value of the heights of the four edges was measured. Asked. The same test was performed three times for each sample, and the average value of the three tests was calculated and evaluated according to the following criteria.

⊚: The average value of the total height of the four ends is 5 mm or less ○: The average value of the total height of the four ends exceeds 5 mm and less than 10 mm ×: The average value of the total height of the four ends is 10 mm or more

(5) Flexibility (MIT test)
The curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 were applied to a polyimide 25 μm substrate having a circuit pattern formed of a sulfuric acid-treated copper thickness of 12 μm with CP56151 manufactured by Microcraft. Then, according to the above "(2) Conditions for forming a cured film", a cured film having a thickness of 20 μm was formed. A MIT test (R = 0.38 mm) based on JIS P8115 was carried out on the obtained cured film, and the flexibility was evaluated.

Specifically, as shown in FIG. 1, the test piece 1 is mounted on the apparatus, the test piece 1 is vertically attached to the clamp 2 with the load F (0.5 kgf) applied, and the bending angle α is set. Bending was performed at 135 degrees and a speed of 175 cpm, and the number of reciprocating bends (times) until breaking was measured. The test environment was 25 ° C., and the radius of curvature was R = 0.38 mm. The evaluation criteria are as follows.

⊚: 200 times or more ○: 150 to 199 times △: 101 to 149 times ×: 100 times or less

(6) Solder heat resistance The curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 have been treated with sulfuric acid by an inkjet printing apparatus CPS6151 (manufactured by Microcraft Co., Ltd.) under a photocuring condition of 800 mJ / cm ² . It was applied onto a circuit pattern substrate having a copper thickness of 12 μm and a polyimide of 50 μm. Then, according to the above "(2) Conditions for forming a cured film", a cured film having a thickness of 20 μm was formed. A rosin-based flux is applied to the obtained evaluation substrate, immersed in a solder bath set at 260 ° C. in advance for 5 seconds once or twice, the flux is washed with a modified alcohol, and then a cross-cut tape peel test is performed. This was performed and the swelling and peeling of the cured film were evaluated. The judgment criteria are as follows.

⊚: No peeling was observed in the cured film even after soaking for 5 seconds x 2 times and performing a peel test with cellophane tape (registered trademark).
◯: No peeling was observed in the cured film even after dipping for 5 seconds x 1 time and performing a peel test with cellophane tape (registered trademark), but when immersed for 5 seconds x 2 times, the cured film swelled and peeled. X: After dipping for 5 seconds × 1 time, the cured film swells and peels off.

(7) Solvent resistance The curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 have been treated with sulfuric acid by an inkjet printing apparatus CPS6151 (manufactured by Microcraft Co., Ltd.) under a photocuring condition of 800 mJ / cm ² . It was applied onto the copper surface of Espanex (registered trademark) M (manufactured by Nittetsu Chemical & Materials Co., Ltd.) and heated at 150 ° C. for 60 minutes in a hot air circulation type drying oven to obtain a cured film having a thickness of 20 μm. The state of the coating film after immersing the cured film in propylene glycol monomethyl acetate for 30 minutes was evaluated. The evaluation criteria are as follows.

○: No change is observed △: Slightly changed ×: Significantly changed

(8) Electrolytic gold plating resistance A circuit in which the curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 are treated with sulfuric acid using an inkjet printing device CPS6151 (manufactured by Microcraft) to have a copper thickness of 12 μm and a polyimide of 50 μm. It was applied on a pattern substrate. Then, according to the above "(2) Conditions for forming a cured film", a cured film having a thickness of 20 μm was formed. The obtained evaluation substrate was gold-plated using a commercially available electroless nickel plating bath and an electroless gold plating bath under the conditions of nickel 5 μm and gold 0.03 μm, and the surface condition of the cured film was observed. The evaluation criteria are as follows.

○: No change is observed ×: Significant whitening or cloudiness occurs

(9) Flame Retardant The curable compositions of Examples 1 to 18 and Comparative Examples 1 to 4 were coated on both sides of Kapton 100H (manufactured by Toray DuPont) using an inkjet printing device CPS6151 (manufactured by Microcraft). .. Then, a cured film was formed according to the above "(2) Conditions for forming a cured film" (the thickness of the coating film on each surface is 20 μm). The obtained cured film was subjected to a thin vertical combustion test conforming to the UL94 standard. The evaluation criteria are as follows.

⊚: VTM-0 passed and the burning time of each sample was less than 7 seconds ○: VTM-0 passed and each sample burned within 10 seconds Not: VTM-0 failed

As shown in Table 2, in Examples 1 to 18 according to the present invention, even after the curable composition has a low viscosity and is applied to a thin film substrate, particularly a particularly thin substrate such as Kapton 100H, and exposed to light. The warpage of the substrate could be suppressed to a low level, and at the same time, the cured coating film was excellent in flexibility and solder heat resistance.

Further, from the comparison between Examples 1 to 3 and 15 and Examples 16 to 18, in addition to being able to impart flame retardancy to the cured coating film by further containing (F) a flame retardant, after exposure. The low warpage is further improved. From the comparison between Examples 14 and 15, the heat resistance of the coating film after curing was further improved because the flame retardant (F) was a phosphorus-based flame retardant.
Although Examples 16 to 18 have failed the flame retardancy test (Not evaluation), this is due to the fact that they do not contain a flame retardant, and the effect of the present invention is not denied. ..

Further, from the comparison between Example 2 and Example 8, (F) when the flame retardant is phenoxyphosphazene, not only the flame retardancy but also the viscosity and the post-exposure warp property of the curable composition are improved. Was done.

Moreover, from the comparison between Example 2 and Example 9, when the ratio of (A) / (B) is larger than 175% by mass, the viscosity of the curable composition, the warpage after exposure, and the flexibility of the cured film are determined. It was found that the characteristics were further improved.

Further, from the comparison between Example 2 and Example 10, when the ratio of (A) / (F) is larger than 49% by mass, the viscosity of the curable composition, the warpage after exposure, and the solder heat resistance of the cured film are obtained. It was found that the sexual characteristics were further improved.

Further, from the comparison between Example 2 and Example 11, when a compound having a (C4) aromatic ring and two or more (meth) acryloyl groups is contained, the flame retardancy and solder heat resistance of the cured film are further contained. From the comparison between Example 2 and Example 12, the cured film further contains (C3) a photocurable compound having no aromatic ring and having three or more (meth) acryloyl groups. It was found that the solder heat resistance characteristics of the solder were improved.

Claims

(A) Equation (1)

(In the formula (1), R 1 may be linear, branched or cyclic, and represents a hydrocarbon group having 1 or more and 4 or less carbon atoms which may contain an ether bond (provided that the hydrocarbon group has 1 or more and 4 or less carbon atoms). The hydrocarbon group may have a substituent)))
The radically polymerizable monomer represented by
(B) A photocurable urethane compound having two (meth) acryloyl groups and
(C) Compounds having (meth) acryloyl groups other than (A) and (B), and
(D) Photopolymerization initiator and
(E) Thermosetting component and
A curable composition comprising.
(F) The curable composition according to claim 1, which contains a flame retardant.
(F) The curable composition according to claim 2, wherein the blending amount of the photocurable urethane compound having two (B) (meth) acryloyl groups with respect to the flame retardant is 1% by mass or more and 70% by mass. thing.
(B) The mixing ratio of the radically polymerizable monomer represented by the formula (1) to the photocurable urethane compound having two (meth) acryloyl groups is 250% by mass or more and 10,000% by mass or less. The curable composition according to any one of claims 1 to 3, wherein the curable composition is characterized by.
(F) Any one of claims 2 to 4, wherein the mixing ratio of the radically polymerizable monomer represented by the formula (A) to the flame retardant is 50% by mass or more and 350% by mass or less. The curable composition according to.
(E) The curable composition according to any one of claims 1 to 5, wherein the thermosetting component contains a latent thermosetting component.
The curable composition according to claim 6, wherein the latent thermosetting component is a blocked isocyanate compound.
(F) The curable composition according to any one of claims 2 to 7, wherein the flame retardant is a phosphorus-based flame retardant.
The curable composition according to claim 8, wherein the phosphorus-based flame retardant is phenoxyphosphazene.
The curable composition according to any one of claims 1 to 9, wherein the viscosity at 50 ° C. is 50 mPa · s or less.
A cured product obtained from the curable composition according to any one of claims 1 to 10.
An electronic component having the cured product according to claim 11.