WO2024063144A1

WO2024063144A1 - Curable composition for ink-jet printing, electronic component, and method for producing electronic component

Info

Publication number: WO2024063144A1
Application number: PCT/JP2023/034306
Authority: WO
Inventors: 孝徳井上; 真澄本田; 崇志福田; 倫久上田; 貴志渡邉
Original assignee: 積水化学工業株式会社
Priority date: 2022-09-22
Filing date: 2023-09-21
Publication date: 2024-03-28

Abstract

Provided is a curable composition for ink-jet printing which, when applied and cured, can give a cured object having heightened adhesiveness to a substrate and having heightened resistance to high-temperature alkali solutions.　The curable composition for ink-jet printing according to the present invention comprises a first (meth)acrylate compound, which has a plurality of (meth)acryloyl groups and an alicyclic skeleton, a second (meth)acrylate compound, which is represented by formula (1), a photopolymerization initiator, and a colorant.

Description

Curable composition for inkjet, electronic component, and method for producing electronic component

The present invention relates to an inkjet curable composition that is applied by an inkjet method. The present invention also relates to an electronic component using the above-mentioned curable composition for inkjet, and a method for manufacturing the electronic component.

In recent years, from the perspective of traceability, marking sections with characters or symbols drawn on the surface of electronic components are formed on the surface of electronic components to record the type and manufacturing information of electronic components such as printed wiring boards and electrolytic capacitors. Sometimes. The marking portion may be formed using a curable composition.

On the other hand, curable compositions that are applied by an inkjet method are known. For example, Patent Document 1 below describes (A) a photopolymerizable monomer having a cyclic skeleton and a shrinkage rate of less than 10%; % or more and 20% or less of a photopolymerizable bifunctional monomer and (C) a photopolymerization initiator.

WO2019/189157A1

When the marking part is formed using a conventional curable composition, when treated with a high temperature (e.g. 60°C) alkaline solution during the manufacturing process of electronic parts (e.g. flux removal process, etc.), the alkaline The liquid may penetrate into the inside of the marking part and the interface between the electronic component and the marking part, and the marking part may peel off from the part to be marked.

Conventional curable compositions for forming marking portions are designed to increase the adhesion between the substrate and the cured product when the curable composition is applied to a substrate and cured, and It is difficult to increase resistance to.

In addition, as a curable composition that can improve the adhesion between the substrate and the cured product and also increase the resistance of the cured product to high-temperature alkaline liquid, we have used a curable composition that can be applied by an inkjet method to coat the marking area. is not known to form.

An object of the present invention is to provide an inkjet curable composition that, when applied and cured, can increase the adhesion between the substrate and the cured product and increase the resistance of the cured product to high-temperature alkaline liquid. An object of the present invention is to provide a curable composition. Another object of the present invention is to provide an electronic component using the above-mentioned curable composition for inkjet, and a method for manufacturing the electronic component.

As a result of intensive studies to solve the above problems, the inventors of the present invention were able to improve the adhesion between the substrate and the cured product, increase the resistance of the cured product to high-temperature alkaline liquid, and apply the coating using an inkjet method. Possible compositions of curable compositions have been discovered.

In this specification, the following curable composition for inkjet, electronic components, and methods for manufacturing electronic components are disclosed.

Item 1. A curable composition for inkjet recording, comprising a first (meth)acrylate compound having a plurality of (meth)acryloyl groups and an alicyclic skeleton, a second (meth)acrylate compound represented by the following formula (1), a photopolymerization initiator, and a colorant.

In the formula (1), R1 and R2 each represent a hydrogen atom or a methyl group, and R3 represents an alkylene group.

Section 2. Item 2. The curable composition for inkjet according to item 1, wherein the colorant contains carbon black.

Section 3. Item 3. The curable composition for inkjet according to Item 1 or 2, wherein the colorant contains a copper phthalocyanine compound.

Section 4. The curable composition for inkjet according to any one of Items 1 to 3, wherein in the formula (1), R3 is an alkylene group having 6 or more and 12 or less carbon atoms.

Item 5. The curable composition for inkjet according to any one of items 1 to 4, wherein the first (meth)acrylate compound has two (meth)acryloyl groups and is a (meth)acrylate compound having a dicyclopentadiene skeleton.

Section 6. Item 6. The curable composition for inkjet according to any one of items 1 to 5, which contains a urethane (meth)acrylate compound having a (meth)acryloyl group.

Section 7. Item 7. The curable composition for inkjet according to item 6, wherein the urethane (meth)acrylate compound is a urethane (meth)acrylate compound having a plurality of (meth)acryloyl groups.

Section 8. Item 8. The curable composition for inkjet according to any one of Items 1 to 7, comprising a (meth)acrylamide compound.

Section 9. Item 9. The curable composition for inkjet according to any one of Items 1 to 8, which does not contain a solvent or contains a solvent in an amount of 1% by weight or less based on 100% by weight of the curable composition for inkjet.

Section 10. Items 1 to 9 further include a dispersant, and the content of the dispersant is 25 parts by weight or more and 150 parts by weight or less with respect to 100 parts by weight of the colorant. Curable composition for inkjet.

Section 11. The inkjet according to any one of Items 1 to 10, wherein the content of the first (meth)acrylate compound in 100% by weight of the curable composition for inkjet is 5% by weight or more and 70% by weight or less. curable composition for use.

Section 12. Item 12. Curing for inkjet according to any one of Items 1 to 11, which does not contain a thermosetting compound or contains a thermosetting compound at 5% by weight or less based on 100% by weight of the curable composition for inkjet. sexual composition.

Section 13. Item 1: When the cured product of the curable composition for inkjet is immersed in water at 60°C for 1 hour and then heated at 170°C for 1 hour, the following weight change rate is less than 5.0%. The curable composition for inkjet according to any one of items 1 to 12.

Weight change rate (%) = |W3-W2|×100/W1

W1: Weight of the cured product of the curable composition for inkjet before immersion W2: Weight of the cured product of the curable composition for inkjet after immersion and before heating W3: Weight of the cured product of the curable composition for inkjet after heating weight

Section 14. Item 14. The curable composition for inkjet according to item 13, wherein the weight change rate is 2.0% or less.

Section 15. Item 15. The curable composition for inkjet according to any one of Items 1 to 14, wherein the cured product of the curable composition for inkjet has a glass transition temperature of 80° C. or higher.

Section 16. Item 16. The inkjet curable composition according to any one of Items 1 to 15, which is used to form a marking part in an electronic component.

Section 17. An electronic component body, and a marking portion disposed on the surface of the electronic component body, the marking portion being formed of the curable composition for inkjet according to any one of Items 1 to 16. , electronic components.

Section 18. A step of applying the curable composition for inkjet according to any one of Items 1 to 16 on the surface of the electronic component main body using an inkjet device to form a marking layer; A method for manufacturing an electronic component, comprising: curing a marking layer to form a marking part.

The curable composition for inkjet according to the present invention comprises a first (meth)acrylate compound having a plurality of (meth)acryloyl groups and an alicyclic skeleton, and a first (meth)acrylate compound represented by the above formula (1). 2 (meth)acrylate compound, a photopolymerization initiator, and a coloring agent. Since the curable composition for inkjet according to the present invention has the above-mentioned configuration, when the curable composition for inkjet is applied and cured, the adhesiveness between the substrate and the cured product is increased, and , the resistance of the cured product to high-temperature alkaline solutions can be increased.

FIGS. 1A and 1B are schematic cross-sectional views for explaining a method of manufacturing an electronic component according to a first embodiment of the present invention.

Hereinafter, the present invention will be explained in detail.

(Curable composition for inkjet)
The curable composition for inkjet according to the present invention (hereinafter sometimes referred to as "curable composition") is used for inkjet coating.

The curable composition according to the present invention contains a first (meth)acrylate compound having a plurality of (meth)acryloyl groups and an alicyclic skeleton, a second (meth)acrylate compound represented by the following formula (1), a photopolymerization initiator, and a colorant.

In the above formula (1), R1 and R2 each represent a hydrogen atom or a methyl group, and R3 represents an alkylene group.

When the marking part is formed using a conventional curable composition, when treated with a high temperature (e.g. 60°C) alkaline solution during the manufacturing process of electronic parts (e.g. flux removal process, etc.), the alkaline The liquid may pass through the inside of the marking part and enter the interface between the electronic component and the marking part, causing the marking part to peel off from the part to be marked. Conventional curable compositions for forming marking portions are designed to increase the adhesion between the substrate and the cured product when the curable composition is applied to a substrate and cured, and It is difficult to increase resistance to.

As a result of intensive studies, the present inventors found that by using a (meth)acrylate compound having multiple (meth)acryloyl groups and an alicyclic skeleton, the high-temperature alkaline liquid can cure the cured product of the composition. It has been found that the resistance of the cured product to high-temperature alkaline liquid can be increased by suppressing the penetration of the cured product into the interior of the alkali solution. The reason for this is that the above-mentioned (meth)acrylate compound having a plurality of (meth)acryloyl groups and an alicyclic skeleton has a rigid molecular skeleton structure, so the glass transition temperature (Tg) It is conceivable that the temperature is higher than the processing temperature (for example, 60° C.) of alkaline liquid in the manufacturing process of electronic components.

On the other hand, when the above-mentioned (meth)acrylate compound having a plurality of (meth)acryloyl groups and an alicyclic skeleton is used alone, the cured product of the curable composition becomes too hard. It was found that the adhesion between the substrate and the cured product was sometimes insufficient. Therefore, the present inventors used a (meth)acrylate compound having a plurality of (meth)acryloyl groups and an alicyclic skeleton in combination with a (meth)acrylate compound represented by a specific structural formula. It has been found that by doing so, it is possible to improve the adhesion between the substrate and the cured product, and to increase the resistance of the cured product to high-temperature alkaline liquid.

Furthermore, since the (meth)acrylate compound represented by the above specific structural formula has a low water absorption rate, it suppresses the absorption of high-temperature alkaline liquid into the curable composition in the manufacturing process of electronic components, and It is possible to suppress the liquid from penetrating into the inside of the cured product of the curable composition.

That is, since the curable composition according to the present invention has the above configuration, when the curable composition is applied and cured, the adhesiveness between the substrate and the cured product is increased, and The resistance of the cured product to high-temperature alkaline liquid can be increased.

The above curable composition can be applied by an inkjet method. An inkjet device is used when applying the above-mentioned curable composition by an inkjet method. The inkjet device has an inkjet head. The inkjet head has an inkjet nozzle. The above-mentioned curable composition is different from a curable composition applied by screen printing, a curable composition applied by a dispenser, and the like.

The curable composition is preferably used to form a marking portion. The curable composition is particularly preferably used to form a marking portion in an electronic component. The marking portion generally contains display information or recorded information composed of characters or symbols. The marking portion preferably contains characters or symbols. The marking portion preferably contains display information or recorded information. The curable composition is particularly preferably used as a marking material for electronic components. The marking portion is preferably formed to a thickness of 1 μm or more and 10 μm or less in the electronic component. The curable composition may be disposed (applied) on the upper surface of the electronic component body, disposed (applied) on the lower surface of the electronic component body, or disposed (applied) inside the electronic component body. The marking portion may be formed on the upper surface of the electronic component body, disposed on the lower surface of the electronic component body, or formed inside the electronic component body. When the marking portion is formed on the upper surface, lower surface, or inside the electronic component body, a traceability function can be imparted to the obtained electronic component.

The color of the curable composition and the marking portion may be the same as or different from the color of the portion to be marked. When the color of the curable composition and the marking portion is the same as the color of the portion to be marked, a traceability function can be imparted to the obtained electronic component without making the marking portion stand out. When the color of the curable composition and the marking portion is different from the color of the portion to be marked, the visibility of the marking portion can be improved.

From the viewpoint of applying the curable composition even better by an inkjet method, it is preferable that the curable composition is liquid at 25°C. The liquid state also includes a paste state.

The viscosity (η1) at 25°C of the curable composition is preferably 40 mPa·s or more, more preferably 60 mPa·s or more, even more preferably 80 mPa·s or more, and preferably 500 mPa·s or less, more preferably is 300 mPa·s or less, more preferably 200 mPa·s or less. When the viscosity (η1) is not less than the lower limit and not more than the upper limit, the curable composition can be applied with a uniform thickness by an inkjet method. The adhesion between the cured product and the cured product can be further improved.

The viscosity (η1) is preferably measured using, for example, an E-type viscometer (“TVE22L” manufactured by Toki Sangyo Co., Ltd.) on the curable composition immediately after preparation at 25° C. and 10 rpm. .

The glass transition temperature (Tg) of the cured product of the curable composition is preferably 80°C or higher, more preferably 90°C or higher, even more preferably 100°C or higher, and preferably 200°C or lower, more preferably 190°C. Below, the temperature is more preferably 180°C or below. When the glass transition temperature of the cured product of the curable composition is at least the above lower limit and below the above upper limit, the resistance of the cured product to high-temperature alkaline liquid is further increased (high-temperature alkaline liquid (infiltration into the interior) can be further suppressed, and the adhesion between the substrate and the cured product can be further improved.

The glass transition temperature of the cured product of the above-mentioned curable composition can be measured using a dynamic viscoelasticity measuring device under the conditions of a heating rate of 10° C./min and a frequency of 10 Hz. Examples of the dynamic viscoelasticity measuring device include "DVA-200" manufactured by IT Keizai Control Co., Ltd.

A cured product of the above-mentioned curable composition can be obtained, for example, by the following method. A step of applying the above curable composition to a thickness of 10 μm using spin coating (for example, “MS-A100” manufactured by Mikasa), and a step of applying an integrated light amount of 1000 mJ/cm ² so that the illuminance at a wavelength of 365 nm is 1000 mW/cm ² The step of irradiating with ultraviolet rays (UV-LED) is repeated to form a cured product (thickness: 300 μm) of the above-mentioned curable composition.

From the viewpoint of further increasing the resistance of the cured product of the above-mentioned curable composition to high-temperature alkaline liquids and further increasing the adhesion between the substrate and the cured product, the cured product of the above-mentioned curable composition should be cured at 60°C. It is preferable that the following weight change rate when heated at 170° C. for 1 hour after being immersed in water for 1 hour is less than 5.0%.

Weight change rate (%) = |W3-W2|×100/W1

W1: Weight of the cured product of the curable composition before immersion W2: Weight of the cured product of the curable composition after immersion and before heating W3: Weight of the cured product of the curable composition after heating

The cured product of the above-mentioned curable composition may be the cured product (thickness: 300 μm) of the above-mentioned curable composition used for measuring the glass transition temperature. The weight of the cured product of the above curable composition is defined as W1. The cured product of the above curable composition is immersed in water at 60° C. for 1 hour, and the weight after wiping off water droplets on the surface is defined as W2. The weight of the cured product of the above-mentioned curable composition after immersion is heated in an oven at 170° C. for 1 hour, and the weight thereof is defined as W3. Let the absolute value of the difference between W2 and W3 be |W3-W2|.

From the viewpoint of further increasing the resistance of the cured product of the curable composition to high-temperature alkaline liquid and further increasing the adhesion between the substrate and the cured product, the weight change rate is preferably less than 5.0%. , more preferably 4.5% or less, further preferably 4.0% or less, particularly preferably 3.0% or less.

From the viewpoint of further increasing the resistance of the cured product of the curable composition to high-temperature alkaline liquid, the weight change rate is preferably 2.0% or less, more preferably 1.5% or less, and even more preferably 1.0%. % or less, particularly preferably 0.9% or less. The lower limit of the weight change rate is not particularly limited. The weight change rate may be 0%, 0% or more, or 0.5% or more. In addition, from the viewpoint of further increasing the adhesion between the substrate and the cured product, the weight change rate is preferably 2.0% or more, and preferably 2.5% or more.

If the high-temperature alkaline liquid penetrates into the inside of the cured product and enters the interface between the substrate and the cured product, the cured product may peel off from the substrate. In other words, the liquid component permeates into the inside of the cured product and the presence of the liquid component at the interface between the substrate and the cured product reduces the contact area at the interface between the substrate and the cured product, causing the cured product to peel off from the substrate. It becomes easier. On the other hand, when the weight change rate is within the above preferable range, it becomes difficult for the liquid component to penetrate into the cured product, thereby suppressing peeling due to a decrease in the contact area at the interface between the substrate and the cured product. be able to. Moreover, when the weight change rate is within the above preferable range, the resistance of the cured product to high-temperature alkaline liquid can be further improved.

Examples of methods for adjusting the weight change rate within the above preferable range include the following methods. A method of adjusting the content of the first (meth)acrylate. A method of adjusting the content of the second (meth)acrylate. A method of adjusting photocuring conditions (for example, wavelength of irradiated light, illuminance, integrated light amount, etc.) of the curable composition. A method of adjusting thermosetting conditions (for example, heating temperature, heating time, etc.) of the curable composition.

From the viewpoint of further increasing the adhesion between the substrate and the cured product by further suppressing the penetration of liquid components into the inside of the cured product, and further increasing the resistance of the cured product to high-temperature alkaline solutions, the above-mentioned In the curable composition, it is particularly preferable that the cured product of the curable composition has a glass transition temperature (Tg) of 80° C. or higher and a weight change rate of less than 5.0%.

Hereinafter, details of each component that can be used in the curable composition according to the present invention will be explained. In addition, in this specification, "(meth)acryloyl" means one or both of "acryloyl" and "methacryloyl", and "(meth)acrylate" means one or both of "acrylate" and "methacrylate". means.

<First (meth)acrylate compound having multiple (meth)acryloyl groups and an alicyclic skeleton>
The curable composition includes a first (meth)acrylate compound having a plurality of (meth)acryloyl groups and an alicyclic skeleton.

Since the above-mentioned curable composition contains the above-mentioned first (meth)acrylate compound, when the above-mentioned curable composition is applied and cured, it is possible to increase the resistance of the cured product to high-temperature alkaline liquid. can.

The first (meth)acrylate compound may be a bifunctional (meth)acrylate compound, a bifunctional or more (meth)acrylate compound, or a trifunctional (meth)acrylate compound. It may be a trifunctional or higher functional (meth)acrylate compound, or a tetrafunctional or higher functional (meth)acrylate compound. The first (meth)acrylate compound may be a (meth)acrylate compound with 20 or less functionalities, a (meth)acrylate compound with 10 or less functionalities, or a (meth)acrylate compound with 5 or less functionalities. It may be. The functional number corresponds to the number of (meth)acryloyl groups. Only one type of the first (meth)acrylate compound may be used, or two or more types may be used in combination.

The first (meth)acrylate compound may have two (meth)acryloyl groups, may have two or more, may have three, or may have three or more (meth)acryloyl groups. It may have 4 or more, it may have 20 or less, it may have 10 or less, or it may have 5 or less.

Examples of bifunctional (meth)acrylate compounds having an alicyclic skeleton include ethoxylated cyclohexane methanol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, 1,3-adamantanediol di(meth)acrylate, and propoxylated cyclohexane methanol di(meth)acrylate.

Examples of the trifunctional (meth)acrylate compound having an alicyclic skeleton include pentaerythritol triacrylate-isophorone diisocyanate-urethane prepolymer.

From the viewpoint of further increasing the resistance of the cured product to high-temperature alkaline liquid when the curable composition is applied and cured, the first (meth)acrylate compound preferably has two (meth)acryloyl groups and preferably has a dicyclopentadiene skeleton. From the viewpoint of further increasing the resistance of the cured product to high-temperature alkaline liquid when the curable composition is applied and cured, the first (meth)acrylate compound is more preferably a (meth)acrylate compound having two (meth)acryloyl groups and a dicyclopentadiene skeleton. In the dicyclopentadiene skeleton of the first (meth)acrylate compound, the double bond portion of dicyclopentadiene may be reacted. For example, the dicyclopentadiene skeleton of the first (meth)acrylate compound may be a skeleton represented by the following formula (2). In the following formula (2), the right end and the left end are bonding sites with other groups.

The first (meth)acrylate compound preferably contains ethoxylated cyclohexanemethanol di(meth)acrylate or tricyclodecane dimethanol di(meth)acrylate, and more preferably contains tricyclodecane dimethanol di(meth)acrylate. Tricyclodecane dimethanol di(meth)acrylate has a skeleton represented by the above formula (2). In addition, from the viewpoint of further increasing the resistance of the cured product to high-temperature alkaline liquid when the curable composition is applied and cured, the first (meth)acrylate compound preferably has a tricyclodecane skeleton.

The glass transition temperature (Tg) of the homopolymer of the first (meth)acrylate compound is preferably 100°C or higher, more preferably 150°C or higher, even more preferably 190°C or higher, and preferably 250°C or lower, More preferably it is 220°C or lower. When the glass transition temperature of the homopolymer of the first (meth)acrylate compound is above the above lower limit and below the above upper limit, when the above curable composition is applied and cured, the substrate and the cured product are bonded. The adhesion can be further improved.

The glass transition temperature of the homopolymer of the first (meth)acrylate compound described above and the glass transition temperature of the homopolymer of the second (meth)acrylate compound described below each have a degree of polymerization of 3000 to 4000 (preferably 3500). ) means the glass transition temperature of the homopolymer.

The above glass transition temperature can be measured in accordance with JIS K7121 using a differential scanning calorimeter at a heating rate of 10° C./min. Examples of the differential scanning calorimeter include "DSC7020" manufactured by Hitachi High-Tech Science.

The content of the first (meth)acrylate compound in 100% by weight of the curable composition is preferably 5% by weight or more, more preferably 10% by weight or more, still more preferably 20% by weight or more, particularly preferably The content is 30% by weight or more, preferably 80% by weight or less, more preferably 70% by weight or less, even more preferably 60% by weight or less. When the content of the first (meth)acrylate compound is not less than the above lower limit and not more than the above upper limit, the effects of the present invention can be exhibited even more effectively.

<Second (meth)acrylate compound represented by formula (1)>
The curable composition contains a second (meth)acrylate compound represented by the following formula (1).

Since the curable composition contains the second (meth)acrylate compound, it is possible to increase the adhesion between the substrate and the cured product when the curable composition is applied and cured. can.

In the above formula (1), R1 and R2 may be the same or different.

From the viewpoint of suppressing the curing shrinkage that occurs when the above-mentioned curable composition is applied and cured, and further increasing the adhesion between the substrate and the cured product, it is necessary to reduce the alkylene group of R3 in the above formula (1). The number of carbon atoms is preferably 2 or more, more preferably 4 or more, even more preferably 6 or more, and preferably 16 or less, more preferably 14 or less, and still more preferably 12 or less. From the viewpoint of suppressing curing shrinkage that occurs when the above-mentioned curable composition is applied and cured, and further increasing the adhesion between the substrate and the cured product, in the above formula (1), R3 is the number of carbon atoms. Particularly preferred is an alkylene group of 6 or more and 12 or less.

Examples of the second (meth)acrylate compound include decanediol di(meth)acrylate, nonanediol di(meth)acrylate, and hexanediol di(meth)acrylate.

From the viewpoint of further increasing the adhesion between the substrate and the cured product when the curable composition is applied and cured, the second (meth)acrylate compound is preferably nonanediol di(meth)acrylate or hexanediol di(meth)acrylate, and more preferably nonanediol di(meth)acrylate.

The glass transition temperature (Tg) of the homopolymer of the second (meth)acrylate compound is preferably -50°C or higher, more preferably -40°C or higher, even more preferably -30°C or higher, and preferably 50°C or higher. The temperature is preferably 40°C or lower, more preferably 40°C or lower. When the glass transition temperature of the homopolymer of the second (meth)acrylate compound is above the above lower limit and below the above upper limit, when the above curable composition is applied and cured, the substrate and the cured product are bonded. The adhesion can be further improved.

The content of the second (meth)acrylate compound in 100% by weight of the curable composition is preferably 10% by weight or more, more preferably 15% by weight or more, even more preferably 20% by weight or more, and preferably is 70% by weight or less, more preferably 60% by weight or less, even more preferably 55% by weight or less. When the content of the second (meth)acrylate compound is at least the above lower limit and below the above upper limit, when the curable composition is applied and cured, the adhesion between the substrate and the cured product is improved. It can be further improved.

The content of the second (meth)acrylate compound is preferably 20 parts by weight or more, more preferably 30 parts by weight or more, and even more preferably is 40 parts by weight or more, preferably 250 parts by weight or less, more preferably 200 parts by weight or less, still more preferably 150 parts by weight or less. When the content of the second (meth)acrylate compound is not less than the above lower limit and not more than the above upper limit, the effects of the present invention can be exhibited even more effectively.

<Photopolymerization initiator>
The curable composition contains the photopolymerization initiator.

Since the curable composition contains the photopolymerization initiator, the curable composition can be cured by irradiation with light.

Examples of the photopolymerization initiators include radical photopolymerization initiators, cationic photopolymerization initiators, and the like. The photopolymerization initiator is preferably a radical photopolymerization initiator. Only one kind of the above-mentioned photopolymerization initiator may be used, or two or more kinds thereof may be used in combination.

The photo-radical polymerization initiator is a compound that generates radicals upon irradiation with light and initiates a radical polymerization reaction. Examples of the photoradical polymerization initiator include benzoin compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether; alkylphenone compounds such as 1-hydroxycyclohexylphenyl ketone and 2-hydroxy-2-methylpropiophenone; Acetophenone compounds such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone; 2-methyl-1-[4-(methylthio)phenyl]- 2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl) )-butanone-1, 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone, 2-(dimethylamino)-1 Aminoacetophenone compounds such as -(4-morpholinophenyl)-2-benzyl-1-butanone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, N,N-dimethylaminoacetophenone; 2-methylanthraquinone, 2 - Anthraquinone compounds such as ethyl anthraquinone and 2-t-butylanthraquinone; thioxanthone compounds such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; acetophenone dimethyl ketal, benzyl Ketal compounds such as dimethyl ketal; acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; 1,2-octanedione; 1-[4-(phenylthio)-2-(o-benzoyloxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(o -acetyloxime); bis(cyclopentadienyl)-di-phenyl-titanium, bis(cyclopentadienyl)-di-chloro-titanium, bis(cyclopentadienyl)-bis(2, Examples include titanocene compounds such as 3,4,5,6-pentafluorophenyl) titanium, bis(cyclopentadienyl)-bis(2,6-difluoro-3-(pyrrol-1-yl)phenyl)titanium, etc. . Only one kind of the above-mentioned radical photopolymerization initiator may be used, or two or more kinds thereof may be used in combination.

The photopolymerization initiator is 2-dimethylamino-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]1-butanone, or 2-(dimethylamino)-1- Preferably, it contains (4-morpholinophenyl)-2-benzyl-1-butanone. By using these preferred photopolymerization initiators, the curability of the curable composition can be improved, so when the curable composition is applied and cured, the adhesion between the substrate and the cured product is improved. It can be further improved.

A photopolymerization initiation aid may be used together with the above-mentioned radical photopolymerization initiator. Examples of the photopolymerization initiation aid include N,N-dimethylaminobenzoic acid ethyl ester, N,N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, and triethanolamine. The photopolymerization initiation aid may be used alone or in combination of two or more.

Additionally, titanocene compounds such as CGI-784 (manufactured by Ciba Specialty Chemicals) that absorb in the visible light region may be used to promote the photoreaction.

Examples of the photocationic polymerization initiator include sulfonium salts, iodonium salts, metallocene compounds, and benzointosylate. Only one kind of the above-mentioned photocationic polymerization initiator may be used, or two or more kinds thereof may be used in combination.

The content of the photopolymerization initiator in 100% by weight of the curable composition is preferably 4% by weight or more, more preferably 5% by weight or more, and preferably 15% by weight or less, more preferably 12% by weight. It is as follows. When the content of the photopolymerization initiator is not less than the lower limit and not more than the upper limit, the curability of the curable composition can be improved, so when the curable composition is applied and cured, Adhesion between the substrate and the cured product can be further improved.

The content of the photopolymerization initiator is preferably 4 parts by weight or more, more preferably 5 parts by weight or more, and preferably 20 parts by weight or less, more preferably 15 parts by weight or less, relative to a total of 100 parts by weight of the first (meth)acrylate compound and the second (meth)acrylate compound. When the content of the photopolymerization initiator is equal to or more than the lower limit and equal to or less than the upper limit, the curability of the curable composition can be increased, and therefore, when the curable composition is applied and cured, the adhesion between the substrate and the cured product can be further increased.

<Colorant>
The curable composition includes the colorant.

Since the above-mentioned curable composition contains the above-mentioned colorant, it is suitably used to form the marking part. Since the curable composition contains the colorant, it is suitably used as a marking material.

Examples of the coloring agent include dyes, pigments, and the like. As for the above-mentioned coloring agent, only 1 type may be used, and 2 or more types may be used together. When only one type of colorant is used, the process for producing the curable composition becomes simpler. When two or more colorants are used together, the color of the curable composition can be easily adjusted.

The above dyes include pyrazole azo dyes, anilinoazo dyes, triphenylmethane dyes, anthraquinone dyes, anthrapyridone dyes, benzylidene dyes, oxole dyes, pyrazolotriazole azo dyes, pyridone azo dyes, and cyanine dyes. Dyes, phenothiazine dyes, pyrrolopyrazole azomethine dyes, xatene dyes, phthalocyanine dyes, benzopyran dyes, indigo dyes, pyrromethene dyes, triarylmethane dyes, azomethine dyes, berylene dyes, perinone dyes, Examples include quatarylene dyes and quinophthalone dyes. The above dyes are acid dyes, direct dyes, basic dyes, mordant dyes, acidic mordant dyes, azoic dyes, disperse dyes, oil-soluble dyes, food dyes, and black color by mixing two or more of these derivatives. It may also be a dye made into a dye. The above dyes may be used alone or in combination of two or more.

The pigment may be an organic pigment or an inorganic pigment. The organic pigment may be an organic pigment having a metal atom or an organic pigment not having a metal atom. Only one type of the pigment may be used, or two or more types may be used in combination.

Examples of the organic pigments include phthalocyanine compounds, quinacridone compounds, azo compounds, pentaphene compounds, perylene compounds, indole compounds, and dioxazine compounds.

Examples of the phthalocyanine compounds include copper phthalocyanine compounds.

Examples of the inorganic pigments include carbon black, carbon nanotubes, graphene, iron oxide, zinc oxide, titanium oxide, calcium carbonate, alumina, kaolin clay, calcium silicate, magnesium oxide, magnesium hydroxide, aluminum hydroxide, magnesium carbonate, talc, Examples include feldspar powder, mica, barite, barium carbonate, silica, and glass beads.

From the viewpoint of increasing heat resistance, the colorant preferably contains a pigment. From the viewpoint of improving visibility, the colorant is preferably a black pigment or a blue pigment.

From the viewpoint of increasing heat resistance, the colorant more preferably contains carbon black or a phthalocyanine compound, and particularly preferably contains carbon black or a copper phthalocyanine compound.

From the viewpoint of improving visibility, the content of the colorant in 100% by weight of the curable composition is preferably 0.1% by weight or more, more preferably 0.5% by weight or more, and preferably 5% by weight or more. It is not more than 3% by weight, more preferably not more than 3% by weight.

<Dispersant>
The curable composition may contain a dispersant. From the viewpoint of improving dispersibility, it is preferable that the curable composition further contains a dispersant. In particular, when the colorant contains carbon black, the curable composition preferably further contains a dispersant.

Examples of the above-mentioned dispersants include polyurethane dispersants, phosphate ester dispersants, carboxylic acid dispersants, amine dispersants, and ricinoleate ester dispersants. The above-mentioned dispersants may be used alone or in combination of two or more.

Examples of the polyurethane dispersant include basic polyurethane, polyurethane-acrylic, polyurethane-polyurea, polyester-polyurethane, polyether-polyurethane, and silicone polyurethane.

Examples of the above-mentioned phosphate dispersants include polyoxyalkylene alkyl phenyl ether phosphates such as polyoxyethylene nonylphenyl ether phosphate, polyoxyethylene tridecyl ether phosphate, and polyoxyethylene octylphenyl ether phosphate. , polyoxyethylene alkyl ether phosphate, polyoxyethylene alkyl ether phosphate/monoethanolamine salt, polyoxyethylene lauryl ether phosphate, polyoxyethylene lauryl ether phosphate/monoethanolamine salt, polyethylene styrenation Examples include phenyl ether phosphate, sodium alkyl phosphate, and alkyl phosphate monoethanolamine salt.

The above carboxylic acid dispersant is preferably a polycarboxylic acid. Examples of the polycarboxylic acid include polycarboxylic acid polymers in which polyoxyalkylene is grafted onto a polymer having a carboxyl group in the main chain skeleton.

The weight average molecular weight of the polycarboxylic acid is preferably 500 or more, more preferably 1000 or more, even more preferably 2000 or more, and preferably 1,500,000 or less, more preferably 1,250,000 or less, even more preferably 1,000,000 or less. The weight average molecular weight is the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

Examples of the above amine dispersants include tetradecylamine acetate, laurylamine, oleylamine, distearylamine, and dimethyllaurylamine.

Examples of the above-mentioned ricinoleic acid ester dispersants include glycerinricinoleic acid monoester, polyglycerinricinoleic acid monoester, and acetyl ricinoleic acid ester.

From the viewpoint of improving dispersibility, it is preferable that the above dispersant contains a phosphate ester-based dispersant.

From the viewpoint of improving dispersibility, the content of the dispersant in 100% by weight of the curable composition is preferably 0.1% by weight or more, more preferably 0.5% by weight or more, and preferably 5% by weight or more. It is at most 3% by weight, more preferably at most 3% by weight, even more preferably at most 2% by weight.

From the viewpoint of improving dispersibility, the content of the dispersant is preferably 25 parts by weight or more, more preferably 50 parts by weight or more, and even more preferably 75 parts by weight, relative to 100 parts by weight of the colorant. The content is preferably 150 parts by weight or less, more preferably 125 parts by weight or less, even more preferably 110 parts by weight or less.

<Solvent>
The curable composition does not contain or contains a solvent. The curable composition may or may not contain a solvent. From the viewpoint of suppressing curing shrinkage that occurs when the solvent evaporates and further improving the adhesion between the substrate and the cured product, the lower the content of the solvent in the curable composition, the better.

Examples of the above-mentioned solvents include water, organic solvents, and the like.

From the viewpoint of further enhancing the removability of residues, the above-mentioned solvent is preferably an organic solvent. Examples of the above-mentioned organic solvents include alcohols such as ethanol, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene, glycol ethers such as cellosolve, methyl cellosolve, butyl cellosolve, carbitol, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol diethyl ether, and tripropylene glycol monomethyl ether, esters such as ethyl acetate, butyl acetate, butyl lactate, cellosolve acetate, butyl cellosolve acetate, carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and propylene carbonate, aliphatic hydrocarbons such as octane and decane, and petroleum-based solvents such as petroleum ether and naphtha.

From the viewpoint of suppressing curing shrinkage that occurs when the solvent evaporates and further increasing the adhesion between the substrate and the cured product, the curable composition does not contain the solvent or the curable composition 100 It is preferable that the above-mentioned solvent is contained in an amount of 5% by weight or less. From the viewpoint of suppressing curing shrinkage that occurs when the solvent evaporates and further increasing the adhesion between the substrate and the cured product, when the curable composition contains the solvent, 100% by weight of the curable composition Among them, the content of the above-mentioned solvent is preferably 5% by weight or less, more preferably 1% by weight or less, and still more preferably 0.5% by weight or less. The lower limit of the content of the solvent is not particularly limited. The content of the solvent may be 0% by weight (not contained), 0% by weight or more, or 0.5% by weight or more.

<Thermosetting compound>
The curable composition does not contain or contains a thermosetting compound. The curable composition may or may not contain a thermosetting compound. From the viewpoint of suppressing the generation of outgas when the curable composition is heated, the lower the content of the thermosetting compound in the curable composition, the better.

Examples of the thermosetting compounds include oxetane compounds, epoxy compounds, episulfide compounds, (meth)acrylic compounds, phenol compounds, amino compounds, unsaturated polyester compounds, polyurethane compounds, silicone compounds, and polyimide compounds. The above thermosetting compounds may be used alone or in combination of two or more.

The thermosetting compound may be used in combination with a thermosetting agent. The curable composition may contain a thermosetting compound and a thermosetting agent. The thermosetting agent thermally cures the thermosetting compound.

Examples of the above-mentioned thermosetting agents include thiol curing agents such as imidazole curing agents, amine curing agents, phenol curing agents, and polythiol curing agents, acid anhydride curing agents, thermal cationic initiators (thermal cationic curing agents), thermal radical generators, etc. can be mentioned. The above thermosetting agents may be used alone or in combination of two or more.

From the viewpoint of further increasing the adhesion between the substrate and the cured product, the curable composition does not contain the thermosetting compound, or the thermosetting compound does not contain the thermosetting compound in 100% by weight of the curable composition. It is preferable that the content is 5% by weight or less. From the perspective of further increasing the adhesion between the substrate and the cured product, when the curable composition contains the thermosetting compound, the content of the thermosetting compound in 100% by weight of the curable composition is preferably 4% by weight or less, more preferably 3% by weight or less, even more preferably 2% by weight or less. The lower limit of the content of the thermosetting compound is not particularly limited. The content of the thermosetting compound may be 0% by weight (not contained), 0% by weight or more, or 0.5% by weight or more.

The content of the thermosetting agent is preferably 10 parts by weight or more, more preferably 20 parts by weight or more, even more preferably 25 parts by weight or more, particularly preferably 30 parts by weight, relative to 100 parts by weight of the thermosetting compound. The content is preferably 60 parts by weight or less, more preferably 55 parts by weight or less, and even more preferably 50 parts by weight. When the content of the thermosetting agent is not less than the lower limit and not more than the upper limit, the thermosetting compound can be cured well.

<Other ingredients>
The curable composition comprises the first (meth)acrylate compound, the second (meth)acrylate compound, the photopolymerization initiator, the colorant, the solvent, the dispersant, and the thermosetting compound. It may also contain other components. Other ingredients listed above include fillers, antifoaming agents, coupling agents, curing agents, curing accelerators, mold release agents, surface treatment agents, flame retardants, viscosity modifiers, dispersants, dispersion aids, and surface modification agents. agents, plasticizers, antibacterial agents, antifungal agents, leveling agents, stabilizers, anti-sagging agents, and phosphors.

The curable composition may contain (meth)acrylate compounds other than the first (meth)acrylate compound and the second (meth)acrylate compound (hereinafter referred to as "other (meth)acrylate compounds"). ) may be included.

The other (meth)acrylate compounds mentioned above may be monofunctional (meth)acrylate compounds or may be polyfunctional (meth)acrylate compounds.

Examples of the other (meth)acrylate compounds include polypropylene glycol #700 diacrylate, polypropylene glycol #400 diacrylate, and tripropylene glycol diacrylate. From the viewpoint of further enhancing the adhesion between the substrate and the cured product, the other (meth)acrylate compound is preferably polypropylene glycol #700 diacrylate.

From the viewpoint of further increasing the adhesion between the substrate and the cured product, the other (meth)acrylate compound (the marking material) preferably contains a urethane (meth)acrylate compound having a (meth)acryloyl group. The urethane (meth)acrylate compound may have one (meth)acryloyl group, may have two or more (meth)acryloyl groups, or may have three or more (meth)acryloyl groups. It may have four or more (meth)acryloyl groups. The urethane (meth)acrylate compound may have 100 or less (meth)acryloyl groups, or may have 50 or less (meth)acryloyl groups. The urethane (meth)acrylate compound may be a monofunctional urethane (meth)acrylate compound or a polyfunctional urethane (meth)acrylate compound.

From the viewpoint of enhancing photocurability, the urethane (meth)acrylate compound is preferably a urethane (meth)acrylate compound having multiple (meth)acryloyl groups. From the viewpoint of further enhancing photocurability, the number of (meth)acryloyl groups in the urethane (meth)acrylate compound is preferably 2 or more, more preferably 3 or more, even more preferably 4 or more, and preferably 8 or less, more preferably 7 or less, even more preferably 6 or less. From the viewpoint of further enhancing photocurability, it is particularly preferable that the urethane (meth)acrylate compound has 4 to 6 (meth)acryloyl groups.

From the viewpoint of further increasing the adhesion between the substrate and the cured product, the urethane (meth)acrylate compound is preferably a urethane (meth)acrylate compound having an aromatic skeleton.

Examples of the aromatic skeleton include a naphthalene skeleton, a fluorene skeleton, a phenyl skeleton, a biphenyl skeleton, an anthracene skeleton, a pyrene skeleton, a xanthene skeleton, an adamantane skeleton, and a bisphenol A type skeleton.

From the viewpoint of further increasing the adhesion between the substrate and the cured product, the aromatic skeleton in the urethane (meth)acrylate compound is preferably a phenyl skeleton or a biphenyl skeleton. From the viewpoint of further increasing the adhesion between the substrate and the cured product, the urethane (meth)acrylate compound preferably contains a urethane (meth)acrylate compound having a phenyl skeleton or a biphenyl skeleton; It is more preferable to include a meth)acrylate compound.

Commercially available products can be used as the urethane (meth)acrylate compound having a biphenyl skeleton. Commercially available urethane (meth)acrylate compounds having the biphenyl skeleton include EBECRYL220 (manufactured by Daicel Allnex) and EBECRYL210 (manufactured by Daicel Allnex).

From the viewpoint of further increasing the adhesion between the substrate and the cured product, it is preferable that the curable composition further contains a (meth)acrylamide compound. From the viewpoint of further increasing the adhesion between the substrate and the cured product, the other (meth)acrylate compound preferably includes a (meth)acrylamide compound.

The above (meth)acrylamide compounds include N,N-dimethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, N,N-dimethylaminopropyl(meth)acrylamide, N , N-diethylaminopropyl (meth)acrylamide, N,N-dimethylaminoethyl (meth)acrylamide, N,N-diethylaminoethyl (meth)acrylamide, and (meth)acryloylmorpholine.

From the viewpoint of further increasing the adhesion between the substrate and the cured product, the (meth)acrylamide compound preferably contains (meth)acryloylmorpholine.

As the above (meth)acryloylmorpholine, commercially available products can be used. Commercially available products of the above (meth)acryloylmorpholine include ACMO (manufactured by KJ Chemicals) and the like.

(Electronic components and methods of manufacturing electronic components)
An electronic component according to the present invention includes an electronic component main body and a marking section arranged on a surface of the electronic component main body. The marking portion is formed from the above-mentioned curable composition for inkjet. The marking portion includes a cured product of the curable composition for inkjet.

The method for manufacturing an electronic component according to the present invention includes the following steps. (1) A step (coating step) of applying the above-described curable composition for inkjet onto the surface of the electronic component main body using an inkjet device to form a marking layer. (2) A step of curing the marking layer by irradiating light to form a marking part (photo-curing step).

Hereinafter, specific embodiments of the present invention will be described with reference to the drawings.

FIGS. 1(a) and 1(b) are schematic cross-sectional views for explaining the method for manufacturing an electronic component according to the first embodiment of the present invention.

First, as shown in FIG. 1(a), a curable composition (marking material) is applied onto the surface of the electronic component main body 1 using an inkjet device to form a marking layer 3A (coating step). . A curable composition (marking material) is discharged from the discharge section 51 of the inkjet device.

Next, as shown in FIG. 1B, the marking layer 3A is irradiated with light from the light irradiation unit 52 of the inkjet device to advance the curing of the marking layer 3A to form the marking portion 3B (photocuring process). Light is irradiated from the light irradiation unit 52 of the inkjet device to harden the marking layer 3A to form the marking portion 3B.

Note that after the photocuring step, the coating step and the photocuring step may be repeated. When the above coating step and the above photocuring step are repeated, the curable composition is applied to the surface side of the formed marking portion 3B opposite to the electronic component main body 1 side.

The thickness of the marking part can be increased by performing each of the above coating step and the above photocuring step multiple times in the thickness direction of the marking layer. The coating step and the photocuring step may each be performed two or more times, three or more times, 1000 times or less, or 100 times or less.

In this way, the electronic component 10 can be obtained.

In the photocuring step, it is preferable that ultraviolet rays be irradiated. The illuminance and irradiation time of ultraviolet rays in the photocuring step can be changed as appropriate depending on the composition of the curable composition and the coating thickness of the curable composition. The illuminance of ultraviolet rays in the photocuring step may be, for example, 1000 mW/cm ² or more, 5000 mW/cm ² or more, 10000 mW/cm ² or less, or 8000 mW/cm ² or less. It may be. The irradiation time of ultraviolet rays in the photocuring step may be, for example, 0.01 seconds or more, 0.1 seconds or more, 400 seconds or less, or 100 seconds or less. Good too.

The width, thickness, etc. of the marking part can be changed as appropriate.

The width of the marking part may be 30 μm or more, 50 μm or more, 70 μm or more, 1000 μm or less, 800 μm or less, or 700 μm or less. There may be.

The thickness of the marking part may be 1 μm or more, 5 μm or more, 100 μm or less, 50 μm or less, 30 μm or less, or 10 μm or less. There may be.

Examples of electronic components include electrolytic capacitors, coils, capacitors, antennas, printed wiring boards, and touch panel components.

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

The following materials were prepared:

First (meth)acrylate compound:
Tricyclodecane dimethanol diacrylate ("IRR-214K" manufactured by Daicel Allnex Corporation, glass transition temperature of homopolymer: 190°C)
Ethoxylated cyclohexanemethanol diacrylate ("HBPE-4" manufactured by Daiichi Kogyo Seiyaku Co., Ltd., glass transition temperature of homopolymer: 50°C)

Second (meth)acrylate compound:
1,9-nonanediol diacrylate (“Viscoat #260” manufactured by Osaka Organic Chemical Industry Co., Ltd., glass transition temperature of homopolymer: 68°C)
1,6-hexanediol diacrylate (“Viscoat #230” manufactured by Osaka Organic Chemical Industry Co., Ltd., glass transition temperature of homopolymer: 63°C)

Other (meth)acrylate compounds:
Propylene oxide modified bisphenol A diacrylate (Kyoeisha Chemical Co., Ltd. "Light Acrylate BP-4PA", homopolymer glass transition temperature: 80°C)
Ethoxylated bisphenol A diacrylate (“ABE-300” manufactured by Shin Nakamura Chemical Co., Ltd., glass transition temperature of homopolymer: 75°C)
Polypropylene glycol #700 diacrylate (“APG-700” manufactured by Shin Nakamura Chemical Co., Ltd., glass transition temperature of homopolymer: 32°C)
Ethylene oxide-modified trimethylolpropane triacrylate (“Laromer LR8863” manufactured by BASF, glass transition temperature of homopolymer: 110°C)
Dipropylene glycol diacrylate (“DPGDA” manufactured by Daicel Allnex, homopolymer glass transition temperature: 110°C)
Urethane acrylate having 6 (meth)acryloyl groups (“EBECRYL220” manufactured by Daicel Allnex, glass transition temperature of homopolymer having an aromatic skeleton: 49°C)
Acryloylmorpholine (acrylamide compound, “ACMO” manufactured by KJ Chemicals)

Photoinitiator:
2,4,6-trimethylbenzoyldiphenylphosphine oxide (“OmniradTPO” manufactured by IGM Resins)
2-dimethylamino-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]1-butanone (“Omnirad379” manufactured by IGM Resins)
Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide (“Omnirad819” manufactured by IGM Resins)

Colorants:
Carbon black ("Carbon Black #10" manufactured by Mitsubishi Chemical Corporation)
Carbon black ("Carbon Black MA14" manufactured by Mitsubishi Chemical Corporation)
Copper phthalocyanine compound (pigment, "Oil Blue 5511-N" manufactured by Orient Chemical Industries Co., Ltd.)
Copper phthalocyanine compound (pigment, "OPLAS BLUE 635" manufactured by Orient Chemical Industries Co., Ltd.)
Titanium oxide (Ishihara Sangyo Kaisha, Ltd. "PF-726")
Pigment Violet 37 (purple pigment, "CROMOPHTAL VIOLET B" manufactured by BASF)
Pigment Red 122 (red pigment, "Fastogen Super Magenta RGT" manufactured by DIC Corporation)
Solvent Green 5 (yellow pigment, "PLAST YELLOW 8025" manufactured by Arimoto Chemical Co., Ltd.)

Dispersant:
Phosphate ester dispersant (“DISPERBYK-106” manufactured by BYK)
Phosphate ester dispersant (“DISPERBYK-145” manufactured by BYK)
Polyacrylic dispersant (manufactured by BASF, "PX4701")
Phosphate ester dispersant (“DISPERBYK-9076” manufactured by BYK)
Polycaprolactone-based dispersant (Ajisper PB821, manufactured by Ajinomoto Fine Techno)

solvent:
Tripropylene glycol monomethyl ether (TPM)

(Examples 1 to 29 and Comparative Examples 1 to 4)
The ingredients shown in Tables 1, 3, 5, 7, 9, 11, and 13 below are blended in the amounts (units are parts by weight) shown in Tables 1, 3, 5, 7, 9, 11, and 13 below. A curable composition for inkjet (curable composition) was obtained.

(evaluation)
(1) Adhesion between the substrate and the cured product A curable composition obtained from an inkjet head of a piezo type inkjet printer equipped with an ultraviolet irradiation device is discharged onto the surface of an aluminum substrate (5 cm x 5 cm in size) and marked. formed a layer. After that, for Examples 1 to 14, 28 to 29 and Comparative Examples 1 to 4, ultraviolet light (UV-LED) was irradiated with an integrated light intensity of 1000 mJ/cm ² so that the illuminance at a wavelength of 365 nm was 1000 mW/cm ^{2 .} Then, the marking layer was cured to form a marking part (thickness: 10 μm). In addition, for Examples 15 to 27, the marking layer was cured by irradiating ultraviolet light (UV-LED) with a cumulative light intensity of 3000 mJ/cm ² so that the illuminance at a wavelength of 365 nm was 6000 mW/cm ² . (thickness: 10 μm). After affixing a tape ("Cello Tape (registered trademark)" manufactured by Nichiban Co., Ltd.) to the entire marking area, the tape was peeled off from the edge. The adhesion (tape peeling resistance) between the substrate and the marking part (cured product) was determined based on the following criteria.

[Criteria for determining adhesion between substrate and cured product]
○○: No peeling of the marking part ○: Area of the peeled part is less than 10% of the total area of the marking part 100% ×: Area of the peeled part exceeds 10% of the total area of the marking part 100%

(2) Resistance to high-temperature alkaline liquid A curable composition obtained from an inkjet head of a piezo type inkjet printer equipped with an ultraviolet irradiation device was discharged onto the surface of an aluminum substrate (5 cm x 5 cm in size) to form a marking layer. Formed. After that, for Examples 1 to 14, 28 to 29 and Comparative Examples 1 to 4, ultraviolet light (UV-LED) was irradiated with an integrated light intensity of 1000 mJ/cm ² so that the illuminance at a wavelength of 365 nm was 1000 mW/cm ^{2 .} Then, the marking layer was cured to form a marking part (thickness: 10 μm). In addition, for Examples 15 to 27, the marking layer was cured by irradiating ultraviolet light (UV-LED) with an integrated light intensity of 3000 mJ/cm ² so that the illuminance at a wavelength of 365 nm was 6000 mW/cm ² . (thickness: 10 μm). The substrate provided with the marking portion was placed in an alkaline solution (pH 9.5, "Cleanthrough 750HS" manufactured by Kao Corporation) heated to 60° C., and 40 kHz ultrasonic waves were applied to clean it for 10 minutes. The resistance of the marking part (cured product) to high-temperature alkaline liquid was determined based on the following criteria.

[Judgment criteria for resistance to high temperature alkaline liquid]
○○: No peeling of the marking part ○: Area of the peeled part is less than 20% of the total area of the marking part 100% ×: Area of the peeled part exceeds 20% of the total area of the marking part 100%

(3) Viscosity at 25°C The viscosity of the obtained curable composition was measured using an E-type viscometer (“TVE22L” manufactured by Toki Sangyo Co., Ltd.) at 25°C and 10 rpm.

(4) Glass transition temperature of cured product For Examples 1 to 14, 28 to 29 and Comparative Examples 1 to 4, the curable composition obtained using spin coating ("MS-A100" manufactured by Mikasa) was A cured product (thickness: 300 μm ⁾ of the curable composition was obtained by repeating the step of applying 10 μm and the step of irradiating ultraviolet rays with a cumulative light intensity of 1000 mJ/cm ² so that the illuminance at a wavelength of 365 nm was 1000 mW/cm 2 . In addition, for Examples 15 to 27, the step of applying 10 μm of the curable composition obtained using spin coating (“MS-A100” manufactured by Mikasa) and the illuminance at a wavelength of 365 nm were set to 6000 mW/cm ² The process of irradiating ultraviolet rays with an integrated light amount of 3000 mJ/cm ² was repeated to obtain a cured product (thickness: 300 μm) of the curable composition. The glass transition temperature of the cured product of the obtained curable composition was measured using a dynamic viscoelasticity measuring device under conditions of a heating rate of 10° C./min and a frequency of 10 Hz.

(5) Weight change rate of cured product When the cured product (thickness: 300 μm) of the curable composition obtained in (1) was immersed in water at 60°C for 1 hour, and then heated at 170°C for 1 hour. , the following weight change rate was calculated.
Weight change rate (%) = |W3-W2|×100/W1
W1: Weight of the cured product of the curable composition before immersion W2: Weight of the cured product of the curable composition after immersion and before heating W3: Weight of the cured product of the curable composition after heating

(6) Discharge properties of curable composition The obtained curable composition was discharged onto the surface of an aluminum substrate (5 cm x 5 cm) from an ink jet head of a piezo type ink jet printer equipped with an ultraviolet irradiation device. The dischargeability of the curable composition was evaluated based on the following criteria. The temperature of the inkjet head was controlled at 25° C. to 75° C. so that the viscosity of the curable composition at the time of ejection was 10 mPa·s, and the curable composition was ejected.

[Criteria for determining dischargeability of curable composition]
○○: The curable composition can be discharged evenly. ○: The curable composition can be discharged, but unevenly. ×: The curable composition cannot be discharged.

(5) Printability of curable composition A curable composition obtained from an inkjet head of a piezo type inkjet printer equipped with an ultraviolet irradiation device was discharged onto the surface of an aluminum substrate (5 cm x 5 cm in size), and characters and Display information (marking layer) consisting of symbols etc. was printed. After that, for Examples 1 to 14, 28 to 29 and Comparative Examples 1 to 4, ultraviolet light (UV-LED) was used with an integrated light intensity of 1000 mJ/cm ² so that the illuminance at a wavelength of 365 nm became 1000 mW/cm ² after 2 seconds. was irradiated to harden the marking layer to form a marking portion (thickness: 10 μm). In addition, for Examples 15 to 27, the marking layer was cured by irradiating ultraviolet light (UV-LED) with an integrated light amount of 3000 mJ/cm ² so that the illuminance at a wavelength of 365 nm was 6000 mW/cm ² after 2 seconds. A marking portion (thickness: 10 μm) was formed. The printability of the curable composition was evaluated based on the following criteria.

[Criteria for determining printability of curable composition]
○○: The information displayed on the marking part is legible. ○: The information displayed on the marking part is partially blurred, but it is legible. ×: The information displayed on the marking part is not legible.

The compositions and results of the curable compositions are shown in Tables 1 to 14 below.

1... Electronic component body 3A... Marking layer 3B... Marking part 10... Electronic component 51... Discharge part 52... Light irradiation part

Claims

A first (meth)acrylate compound having a plurality of (meth)acryloyl groups and an alicyclic skeleton;
A second (meth)acrylate compound represented by the following formula (1),
a photopolymerization initiator;
A curable composition for inkjet, comprising a colorant.

In the formula (1), R1 and R2 each represent a hydrogen atom or a methyl group, and R3 represents an alkylene group.
The curable composition for inkjet according to claim 1, wherein the colorant contains carbon black.
The curable composition for inkjet according to claim 1 or 2, wherein the colorant contains a copper phthalocyanine compound.
The curable composition for inkjet according to any one of claims 1 to 3, wherein in formula (1), R3 is an alkylene group having 6 to 12 carbon atoms.
The first (meth)acrylate compound is a (meth)acrylate compound having two (meth)acryloyl groups and a dicyclopentadiene skeleton, according to any one of claims 1 to 4. Curable composition for inkjet.
The curable composition for inkjet according to any one of claims 1 to 5, comprising a urethane (meth)acrylate compound having a (meth)acryloyl group.
The curable composition for inkjet according to claim 6, wherein the urethane (meth)acrylate compound is a urethane (meth)acrylate compound having a plurality of (meth)acryloyl groups.
The curable composition for inkjet according to any one of claims 1 to 7, comprising a (meth)acrylamide compound.
The curable composition for inkjet according to any one of claims 1 to 8, which does not contain a solvent or contains a solvent at 1% by weight or less based on 100% by weight of the curable composition for inkjet.
further contains a dispersant,
The curable composition for inkjet according to any one of claims 1 to 9, wherein the content of the dispersant is 25 parts by weight or more and 150 parts by weight or less with respect to 100 parts by weight of the colorant. thing.
The content of the first (meth)acrylate compound in 100% by weight of the curable composition for inkjet is 5% by weight or more and 70% by weight or less, according to any one of claims 1 to 10. Curable composition for inkjet.
The composition for inkjet according to any one of claims 1 to 11, which does not contain a thermosetting compound or contains 5% by weight or less of a thermosetting compound based on 100% by weight of the curable composition for inkjet. Curable composition.
A claim in which the following weight change rate when a cured product of the curable composition for inkjet is immersed in water at 60°C for 1 hour and then heated at 170°C for 1 hour is less than 5.0%. The curable composition for inkjet according to any one of items 1 to 12.
Weight change rate (%) = |W3-W2|×100/W1
W1: Weight of the cured product of the curable composition for inkjet before immersion W2: Weight of the cured product of the curable composition for inkjet after immersion and before heating W3: Weight of the cured product of the curable composition for inkjet after heating weight
The curable composition for inkjet according to claim 13, wherein the weight change rate is 2.0% or less.
The curable composition for inkjet according to any one of claims 1 to 14, wherein the cured product of the curable composition for inkjet has a glass transition temperature of 80°C or higher.
The curable composition for inkjet according to any one of claims 1 to 15, which is used to form a marking part in an electronic component.
comprising an electronic component main body and a marking section disposed on the surface of the electronic component main body,
An electronic component, wherein the marking portion is formed from the inkjet curable composition according to any one of claims 1 to 16.
Forming a marking layer by applying the inkjet curable composition according to any one of claims 1 to 16 on the surface of the electronic component body using an inkjet device;
A method for manufacturing an electronic component, comprising the step of curing the marking layer by irradiating light to form a marking part.