Curable composition for inkjet and air cavity formation, electronic component, and method for producing electronic component

Abstract

To provide a curable composition for inkjet and air cavity formation that enables formation of a cured product layer with a large aspect ratio and improves thermal cycle properties of the cured product.SOLUTION: The curable composition for inkjet and air cavity formation according to the present invention comprises a photopolymerizable compound, a photopolymerization initiator, and rubber particles, wherein the photopolymerizable compound includes a first photopolymerizable compound having three or more (meth)acryloyl groups, and the rubber particles are core-shell particles each comprising a core and a shell disposed on the surface of the core.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a curable composition for inkjet printing and for forming air cavities, which is applied using an inkjet device. The present invention also relates to an electronic component using the curable composition, and a method for producing an electronic component using the curable composition. [Background technology]

[0002] A communication filter has an air cavity (space) formed by an RDL layer and a metal, etc. Conventionally, the air cavity has been formed using a sheet material such as a photosensitive polyimide resin sheet or an epoxy resin sheet (for example, Patent Document 1 below).

[0003] Although it is not a composition for forming a resin portion that forms an air cavity, a photocurable and thermosetting composition for inkjet printing is disclosed in Patent Document 2 listed below. This photocurable and thermosetting composition for inkjet printing contains a monomer having a (meth)acryloyl group and a glycidyl group and having a viscosity of 10 mPa s or less at 25°C, a tri- or higher functional acrylate monomer, a thermosetting catalyst, and a photopolymerization initiator. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-278971 [Patent Document 2] Japanese Patent Application Laid-Open No. 2012-214533 Summary of the Invention [Problem to be solved by the invention]

[0005] Conventional air cavity formation methods using sheet materials have high manufacturing costs and complicated manufacturing processes. Furthermore, when the periphery of the filter structure is molded with resin, the resin can penetrate the sheet material and enter the air cavity. To improve the communication reliability of communication filters, it is necessary to prevent the molding material (resin) from entering the air cavity. Therefore, an air cavity with better sealing properties is needed.

[0006] One possible method for improving the air cavity sealing property is to apply a curable composition to a predetermined area using an inkjet device and then form an air cavity by curing the applied curable composition. For example, if the top surface of a first member (circuit board) and the side surface of a second member (electronic member) can be bonded with a cured layer of the curable composition, an air cavity can be formed by the first member, the second member, and the cured layer.

[0007] The above-mentioned Patent Document 2 discloses a photocurable and thermosetting composition for inkjet printing, which contains a monomer having a (meth)acryloyl group and a glycidyl group and having a viscosity of 10 mPa·s or less at 25°C, a tri- or higher functional acrylate monomer, a thermosetting catalyst, and a photopolymerization initiator.

[0008] However, it is difficult to form a cured product layer with a large aspect ratio using conventional inkjet curable compositions such as those described in Patent Document 2. As a result, the curable composition may come into contact with components arranged around the electronic component, resulting in reduced sealing properties. Furthermore, conventional inkjet curable compositions and cured products thereof may have poor thermal cycle characteristics (resistance to thermal shock). Therefore, when an electronic component including a cured product of a conventional inkjet curable composition is repeatedly heated and cooled during use, cracks or fractures (cracks) may occur in the cured product.

[0009] In order to prevent the occurrence of such cracks or fractures, an inorganic filler is sometimes added to the curable composition for inkjet. However, when a large amount of inorganic filler is added to a conventional curable composition for inkjet, there is a problem that the inkjet ejection properties are deteriorated.

[0010] For this reason, it is difficult to use conventional curable compositions for inkjet printing to form air cavities.

[0011] An object of the present invention is to provide a curable composition for inkjet printing and for forming air cavities, which can form a cured product layer having a large aspect ratio and can improve the thermal cycling properties of the cured product. Another object of the present invention is to provide an electronic component using the curable composition, and a method for producing an electronic component using the curable composition. [Means for solving the problem]

[0012] This specification discloses the following curable compositions for inkjet printing and for forming air cavities, electronic components, and methods for producing electronic components.

[0013] Item 1. A curable composition for inkjet printing and for forming air cavities, comprising: a photocurable compound; a photopolymerization initiator; and rubber particles, wherein the photocurable compound comprises a first photocurable compound having three or more (meth)acryloyl groups; and the rubber particles are core-shell particles having a core and a shell disposed on the surface of the core.

[0014] Item 2. The curable composition for inkjet printing and for forming an air cavity according to Item 1, wherein the content of the first photocurable compound is 1% by weight or more and 10% by weight or less, based on 100% by weight of the curable composition for inkjet printing and for forming an air cavity.

[0015] Item 3. The curable composition for inkjet printing and air cavity formation according to Item 1 or 2, wherein the first photocurable compound includes a photocurable compound having six or more (meth)acryloyl groups.

[0016] Item 4. The curable composition for inkjet printing and for forming an air cavity according to any one of Items 1 to 3, wherein the first photocurable compound includes dipentaerythritol hexa(meth)acrylate.

[0017] Item 5. The curable composition for inkjet printing and for forming an air cavity according to any one of Items 1 to 4, wherein the content of the rubber particles is 5% by weight or more and 10% by weight or less, based on 100% by weight of the curable composition for inkjet printing and for forming an air cavity.

[0018] Item 6. The curable composition for inkjet printing and air cavity formation according to any one of Items 1 to 5, wherein the rubber particles contain silicone rubber or polybutadiene rubber.

[0019] Item 7. The curable composition for inkjet printing and for forming an air cavity according to any one of Items 1 to 6, wherein the photocurable compound includes a second photocurable compound different from the first photocurable compound, and the second photocurable compound includes a photocurable compound having two or less (meth)acryloyl groups or a cyclopolymerizable compound.

[0020] Item 8. The curable composition for use in inkjet printing and for forming an air cavity according to Item 7, wherein the second photocurable compound includes a cyclopolymerizable compound, and the content of the cyclopolymerizable compound is 20% by weight or more and 50% by weight or less in 100% by weight of the curable composition for use in inkjet printing and for forming an air cavity.

[0021] Item 9. The curable composition for inkjet printing and for forming an air cavity according to any one of Items 1 to 8, further comprising a thermosetting compound and a thermosetting agent.

[0022] Item 10. An electronic component comprising a circuit board, an electronic member, and an adhesive part, wherein the electronic member is mounted on the circuit board, the adhesive part is a cured product of the curable composition for inkjet printing and for forming an air cavity according to any one of Items 1 to 9, the adhesive part is in contact with an upper surface of the circuit board and at least a part of a side surface of the electronic member, and an air cavity is formed by the circuit board, the electronic member, and the adhesive part.

[0023] Item 11. A method for producing an electronic component, comprising: a step of applying the inkjet and air-cavity-forming curable composition according to any one of Items 1 to 9 to the upper surface of a circuit board mounted on the upper surface of the circuit board by an inkjet method to form a curable composition layer; and a step of curing the curable composition layer to form an adhesive part, wherein in the step of forming the curable composition layer, the curable composition layer is formed so as to contact at least a part of a side surface of the electronic part, and an air cavity is formed by the circuit board, the electronic part, and the adhesive part. [Effects of the Invention]

[0024] The curable composition for inkjet printing and for forming air cavities according to the present invention comprises a photocurable compound, a photopolymerization initiator, and rubber particles. In the curable composition for inkjet printing and for forming air cavities according to the present invention, the photocurable compound comprises a first photocurable compound having three or more (meth)acryloyl groups. In the curable composition for inkjet printing and for forming air cavities according to the present invention, the rubber particles are core-shell particles comprising a core and a shell disposed on the surface of the core. Because the curable composition for inkjet printing and for forming air cavities according to the present invention has the above-mentioned configuration, it is possible to form a cured product layer with a large aspect ratio and to improve the thermal cycling properties of the cured product. [Brief explanation of the drawings]

[0025] [Figure 1]FIG. 1(a) is a plan view schematically showing an electronic component according to a first embodiment of the present invention, and FIG. 1(b) is a cross-sectional view schematically showing the electronic component. [Figure 2] 2(a) and 2(b) are cross-sectional views illustrating the steps of the method for manufacturing the electronic component shown in FIG. [Figure 3] 3(c) and 3(d) are cross-sectional views illustrating the steps of the method for manufacturing the electronic component shown in FIG. [Figure 4] 4(e) to 4(g) are cross-sectional views illustrating the steps of the method for manufacturing the electronic component shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0026] The present invention will be described in detail below.

[0027] (Curable composition for inkjet printing and for forming air cavities) The curable composition for inkjet printing and for forming air cavities (hereinafter sometimes referred to as "curable composition") according to the present invention is applied using an inkjet device. The curable composition is applied by an inkjet method. The curable composition is different from curable compositions applied by screen printing and different from curable compositions applied by a dispenser.

[0028] The curable composition includes (A) a photocurable compound, (B) a photopolymerization initiator, and (C) rubber particles. The curable composition may or may not further include (D) a thermosetting compound. The curable composition may or may not further include (E) a thermosetting agent.

[0029] In the curable composition, the (A) photocurable compound contains a first photocurable compound having three or more (meth)acryloyl groups (hereinafter, sometimes referred to as "(A1) first photocurable compound"). The (A) photocurable compound contains the (A1) first photocurable compound.

[0030] Conventional curable compositions have a problem in that it is difficult to improve the thermal cycle characteristics (thermal shock resistance) of the cured product, and therefore, when an electronic component including a cured product of a conventional curable composition is repeatedly heated and cooled during use, cracks may occur in the cured product.

[0031] Furthermore, conventional curable compositions have the problem that it is difficult to improve reflow resistance, and therefore, when conventional curable compositions are used for electronic components, cracks may occur in the cured product after the reflow process.

[0032] In order to improve the thermal cycle characteristics and reflow resistance of the cured product, a filler is sometimes added to the curable composition. However, when a large amount of filler is added to the curable composition, ejection defects may occur when the curable composition is ejected using an inkjet device.

[0033] Furthermore, for example, when air cavities are formed using a cured product of a conventional curable composition, the air cavities may not be formed satisfactorily because the conventional curable composition is not intended to be used to form air cavities. In particular, with a conventional curable composition for inkjet printing, it may not be possible to satisfactorily form a cured product layer having a large aspect ratio using an inkjet device.

[0034] The curable composition according to the present invention, having the above-described configuration, can improve thermal cycle properties (thermal shock resistance) and form a cured layer with a large aspect ratio. The curable composition according to the present invention can form a cured layer with a large height-to-width ratio. More specifically, the use of (C) rubber particles improves thermal cycle properties (particularly crack suppression), and the use of (A1) first photocurable compound can form a cured layer with a large aspect ratio. The curable composition according to the present invention can form a cured layer with a large aspect ratio, allowing the distance between the bonded components (the distance between the circuit board and the electronic component) to be controlled to a desired distance. Therefore, the curable composition according to the present invention can effectively form an air cavity between, for example, a circuit board, an electronic component, and an adhesive joint formed by the cured product of the curable composition.

[0035] Furthermore, the curable composition according to the present invention can improve reflow resistance, and in an electronic component using the curable composition according to the present invention, cracks can be prevented from occurring in the cured product of the curable composition after a reflow process.

[0036] Furthermore, since the curable composition according to the present invention has the above-described configuration, bleeding (smearing) in the curable composition layer can be suppressed, and as a result, a cured layer having a large aspect ratio can be formed. The curable composition according to the present invention can form a cured layer having an aspect ratio (height / width) required for electronic components.

[0037] Furthermore, the curable composition according to the present invention can be applied to the vicinity of a light-emitting device with high precision using an inkjet device, and therefore the resulting electronic component can be made smaller.

[0038] Furthermore, the curable composition according to the present invention can improve the thermal cycle characteristics and reflow resistance of the cured product of the curable composition even when no filler is added or when a small amount of filler is added. Because the curable composition according to the present invention does not require the addition of a filler, the curable composition can be ejected well using an inkjet device and can be applied with high precision near a light-emitting device, allowing the resulting electronic component to be miniaturized.

[0039] The curable composition is applied using an inkjet device and is therefore generally liquid at 23° C. The viscosity of the curable composition at 23° C. and 10 rpm is preferably 3 mPa·s or more, more preferably 5 mPa·s or more, even more preferably 10 mPa·s or more, and even more preferably 160 mPa·s or more, and is preferably 2000 mPa·s or less, more preferably 1600 mPa·s or less, and even more preferably 1500 mPa·s or less.

[0040] The viscosity is measured at 23° C. using an E-type viscometer (for example, "TVE22L" manufactured by Toki Sangyo Co., Ltd.) in accordance with JIS K2283.

[0041] Light with a wavelength of 365 nm and an illuminance of 2000 mW / cm 2 When the curable composition is irradiated under the conditions of 100 s for 10 seconds and 0.1 seconds to obtain a B-staged product, the storage modulus of the B-staged product at 50°C is preferably 0.5 MPa·s or more, and preferably 10 MPa·s or less.

[0042] The storage modulus of the B-staged product at 50°C is preferably 0.5 MPa·s or more, more preferably 0.8 MPa·s or more, even more preferably 1 MPa·s or more, particularly preferably 1.5 MPa·s or more, and most preferably 2 MPa·s or more. The storage modulus of the B-staged product at 50°C is preferably 10 MPa·s or less, more preferably 8 MPa·s or less, even more preferably 5 MPa·s or less, particularly preferably 4 MPa·s or less, and most preferably 3 MPa·s or less. When the storage modulus of the B-staged product at 50°C is at least the above lower limit, a cured product layer with a large aspect ratio can be more satisfactorily formed, and sealing properties can be further improved. When the storage modulus of the B-staged product at 50°C is at most the above upper limit, sealing properties can be further improved.

[0043] The storage modulus of the B-staged product at 50°C can be measured, for example, by the following method. The curable composition is applied to the surface of a PET film using a spin coater to form a curable composition layer (thickness: 5 µm) (application step). Next, the curable composition layer is irradiated with light to promote curing of the curable composition layer and form a B-staged product (B-staged product layer) (photocuring step). Note that the light irradiation in the photocuring step is performed using a UV-LED lamp with a main wavelength of 365 nm at 2000 mW / cm. 2 ×0.1 seconds (accumulated light intensity 200 mJ / cm 2 ) In the coating step and the photocuring step, coating and photocuring are repeated in the thickness direction of the curable composition layer to form a B-staged product (B-staged product layer, thickness 400 μm). The storage modulus of the B-staged product at 50°C is measured using a viscoelasticity measuring device (for example, the "ARES Viscoelasticity Measuring Device" manufactured by TA Instruments) under conditions of 50°C, measurement plate: parallel plates with a diameter of 25 mm, and a frequency of 1 Hz.

[0044] Methods for adjusting the storage modulus at 50°C of the B-staged product within a preferred range include the following methods: (A) A method using a preferred photocurable compound as the photocurable compound, as described below. (A) A method for adjusting the content of the photocurable compound, (C) A method for using preferred rubber particles as the rubber particles, as described below. (C) A method for adjusting the content of the rubber particles. From the viewpoint of being able to more effectively form a cured product layer with a large aspect ratio, the methods for adjusting the storage modulus at 50°C of the B-staged product within a preferred range are particularly preferably (C) A method for using preferred rubber particles as the rubber particles, as described below, or (C) A method for adjusting the content of the rubber particles.

[0045] Light with a wavelength of 365 nm and an illuminance of 2000 mW / cm 2 When the curable composition is irradiated under conditions of 0.1 second and 0.5 second to obtain a B-staged product, the curable composition is preferably capable of forming a B-staged product having a height-to-width ratio (height / width) (aspect ratio) of 1.0 or more. The curable composition is preferably capable of forming a B-staged product having a height / width ratio of 1.0 or more, more preferably a B-staged product having a height / width ratio of 1.5 or more, and even more preferably a B-staged product having a height / width ratio of 2.0 or more. When the curable composition is capable of forming a B-staged product having a height / width ratio of 1.0 or more, a cured product layer having a high height / width ratio (aspect ratio) can be formed, and adhesion and sealability can be further improved. The height / width ratio may be 100 or less, 50 or less, 10 or less, or 5.0 or less.

[0046] The B-staged product for measuring the ratio (height / width) can be formed by the following method: The curable composition is applied using an inkjet device to form a curable composition layer (application step). Then, the curable composition is applied to a substrate at an illuminance of 2000 mW / cm at a wavelength of 365 nm. 2 The cumulative light intensity is 200mJ / cm 2The curable composition layer is irradiated with light, and the curing of the curable composition layer is advanced to form a B-staged product (B-staged product layer) (photocuring step). In the coating step and the photocuring step, coating and photocuring are repeated in the thickness direction of the curable composition layer to form a B-staged product (B-staged product layer).

[0047] The curable composition according to the present invention can form a cured layer having a high height-to-width ratio. The curable composition according to the present invention can be suitably used to form a cured layer having a height-to-width ratio (height / width) (aspect ratio) of 1.0 or more (use of the curable composition for forming a cured layer having a height-to-width ratio (height / width) (aspect ratio) of 1.0 or more). The height / width ratio of the cured layer is preferably 1.5 or more, more preferably 2.0 or more, and even more preferably 2.5 or more, and may be 100 or less, 50 or less, 10 or less, or 5.0 or less.

[0048] The curable composition can be used to bond a circuit board to an electronic component and form an air cavity. The curable composition can be used to manufacture an electronic component having an air cavity. The curable composition is preferably a curable composition used to bond the upper surface of the circuit board to at least a portion of the side surface of the electronic component, and more preferably a curable composition used to bond the upper surface of the circuit board to the entire side surface of the electronic component. In this case, the curable composition may be a curable composition used to bond the upper surface of the circuit board to the side surface and upper surface of the electronic component.

[0049] Hereinafter, each component that can be used in the curable composition will be described in detail. In this specification, "(meth)acryloyl" refers to "acryloyl" or "methacryloyl", and "(meth)acrylate" refers to "acrylate" or "methacrylate".

[0050] <(A) Photocurable compound> The curable composition contains (A) a photocurable compound. The (A) photocurable compound is a compound that can be photocured. The (A) photocurable compound is a compound that has a photocurable functional group. Only one type of (A) photocurable compound may be used, or two or more types may be used in combination.

[0051] <(A1) First Photocurable Compound> The (A) photocurable compound includes (A1) a first photocurable compound. The (A1) first photocurable compound is a photocurable compound having three or more (meth)acryloyl groups. Only one type of (A1) first photocurable compound may be used, or two or more types may be used in combination.

[0052] The first photocurable compound (A1) may have 3 (meth)acryloyl groups, or may have 3 or more, or may have 4 or more, or may have 5 or more, or may have 6 or more, or may have 20 or less, or may have 10 or less, or may have 8 or less (meth)acryloyl groups.

[0053] The (A1) first photocurable compound is a polyfunctional (meth)acrylate compound. The (A1) first photocurable compound may be a trifunctional (meth)acrylate compound, a tetrafunctional (meth)acrylate compound, a pentafunctional (meth)acrylate compound, or a hexafunctional (meth)acrylate compound. The (A1) first photocurable compound may be a heptafunctional or higher (meth)acrylate compound. It may also be a decafunctional or lower (meth)acrylate compound. The functionality corresponds to the number of (meth)acryloyl groups.

[0054] Examples of the trifunctional (meth)acrylate include trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, alkylene oxide-modified tri(meth)acrylate of trimethylolpropane, pentaerythritol tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, trimethylolpropane tri((meth)acryloyloxypropyl)ether, alkylene oxide-modified tri(meth)acrylate of isocyanuric acid, dipentaerythritol propionate tri(meth)acrylate, tri((meth)acryloyloxyethyl)isocyanurate, and sorbitol tri(meth)acrylate.

[0055] Examples of the tetrafunctional (meth)acrylate include pentaerythritol tetra(meth)acrylate, sorbitol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, and dipentaerythritol propionate tetra(meth)acrylate.

[0056] Examples of the pentafunctional (meth)acrylate include sorbitol penta(meth)acrylate and dipentaerythritol penta(meth)acrylate.

[0057] Examples of the hexafunctional (meth)acrylate include dipentaerythritol hexa(meth)acrylate, ethoxylated dipentaerythritol hexa(meth)acrylate, sorbitol hexa(meth)acrylate, and alkylene oxide-modified hexa(meth)acrylate of phosphazene.

[0058] From the viewpoint of favorably forming a cured material layer having a larger aspect ratio, the first photocurable compound (A1) preferably contains a hexafunctional or higher (meth)acrylate compound. From the viewpoint of favorably forming a cured material layer having a larger aspect ratio, the first photocurable compound (A1) preferably contains a photocurable compound having six or more (meth)acryloyl groups, and more preferably contains dipentaerythritol hexa(meth)acrylate.

[0059] The (A1) first photocurable compound may or may not have a thermosetting functional group. Examples of the thermosetting functional group include a maleimide group, a cyclic ether group, a cyclic thioether group, a thiirane group, and a vinyl group. The cyclic ether group may be an epoxy group. From the viewpoint of favorably forming a cured material layer having a larger aspect ratio, the (A1) first photocurable compound preferably does not have a thermosetting functional group. From the viewpoint of favorably forming a cured material layer having a larger aspect ratio, the (A1) first photocurable compound preferably contains a photocurable compound having three or more (meth)acryloyl groups and no thermosetting functional group, and more preferably contains a photocurable compound having six or more (meth)acryloyl groups and no thermosetting functional group.

[0060] <(A2) Second photocurable compound> The (A) photocurable compound may or may not contain a photocurable compound different from the (A1) first photocurable compound (hereinafter, sometimes referred to as "(A2) second photocurable compound"). The (A) photocurable compound may or may not contain a photocurable compound other than the (A1) first photocurable compound. The (A) photocurable compound may contain a photocurable compound different from the (A1) first photocurable compound and the (A2) second photocurable compound. Only one type of (A2) second photocurable compound may be used, or two or more types may be used in combination.

[0061] From the viewpoint of further enhancing the photocurability of the curable composition and successfully forming partition walls with an even larger aspect ratio, it is preferable that the (A) photocurable compound contains a second photocurable compound (A2) different from the first photocurable compound (A1). From the viewpoint of further enhancing the photocurability of the curable composition and successfully forming partition walls with an even larger aspect ratio, it is preferable that the (A) photocurable compound contains a first photocurable compound (A1) and a second photocurable compound (A2).

[0062] The second photocurable compound (A2) has a photocurable functional group, such as a (meth)acryloyl group or a vinyl group.

[0063] From the viewpoint of favorably forming a cured product layer with an even larger aspect ratio, the second photocurable compound (A2) preferably has a (meth)acryloyl group.

[0064] From the viewpoint of further improving the thermal cycle properties (particularly crack suppression properties) of the cured product of the curable composition, it is preferable that the first photocurable compound (A1) contains a cyclopolymerizable compound.

[0065] From the viewpoint of favorably forming a cured material layer having a larger aspect ratio, the second photocurable compound (A2) preferably contains a photocurable compound having two or less (meth)acryloyl groups or a cyclopolymerizable compound. From the viewpoint of favorably forming a cured material layer having a larger aspect ratio, the second photocurable compound (A2) preferably contains a monofunctional (meth)acrylate compound, a bifunctional (meth)acrylate compound, or a cyclopolymerizable compound.

[0066] Examples of the monofunctional (meth)acrylate include methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, i-propyl (meth)acrylate, n-butyl (meth)acrylate, i-butyl (meth)acrylate, sec-butyl (meth)acrylate, t-butyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, allyl (meth)acrylate, benzo ... methyl (meth)acrylate, phenyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, methoxydiethylene glycol (meth)acrylate, methoxytriethylene glycol (meth)acrylate, methoxypropylene glycol (meth)acrylate, methoxydipropylene glycol (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, glycerol mono(meth)acrylate, 2-ethylhexyl (meth)acrylate, naphthyl (meth)acrylate, lauryl (meth)acrylate, and stearyl (meth)acrylate.

[0067] Examples of the bifunctional (meth)acrylate include 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanedi(meth)acrylate, 1,10-decanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2,4-dimethyl-1,5-pentanediol di(meth)acrylate, butylethylpropanediol di(meth)acrylate, polyethylene glycol di(meth)acrylate, oligoethylene glycol di(meth)acrylate, ethylene glycol di(meth)acrylate, 2-ethyl-2-butylbutanediol di(meth)acrylate, 2-ethyl-2-butylpropanediol di(meth)acrylate, and dipropylene glycol di(meth)acrylate.

[0068] From the viewpoints of further enhancing the photocurability of the curable composition, favorably forming partition walls with a larger aspect ratio, increasing the glass transition temperature (Tg) of the cured product of the curable composition, and further improving the thermal cycle properties (particularly crack suppression properties) of the cured product of the curable composition, it is preferable that the (A2) second photocurable compound contains the cyclopolymerizable compound. The cyclopolymerizable compound is a compound capable of cyclopolymerization. The cyclopolymerizable compound has a cyclopolymerizable group. The cyclopolymerizable compound is capable of forming a polymer having a cyclic skeleton. It is preferable that the cyclopolymerizable compound is capable of forming a polymer having a cyclic skeleton in the main chain.

[0069] The cyclopolymerizable compound is preferably cyclized by radical polymerization. The cyclopolymerizable compound is preferably capable of forming a polymer having a cyclic skeleton by radical polymerization, more preferably capable of forming a polymer having a cyclic skeleton in the main chain by radical polymerization. In the cyclopolymerizable compound, it is preferable that the radical polymerization reaction proceeds while cyclizing.

[0070] From the viewpoint of increasing the adhesive strength between a substrate and a cured product of the curable composition and further improving the thermal cycling properties (particularly, crack suppression) of the cured product of the curable composition, the cyclopolymerizable compound is preferably capable of forming a 5-membered ring structure or a 6-membered ring structure, and more preferably capable of forming a 5-membered ring ether structure or a 6-membered ring ether structure. From the viewpoint of increasing the adhesive strength between a substrate and a cured product of the curable composition and further improving the thermal cycling properties (particularly, crack suppression) of the cured product of the curable composition, the cyclopolymerizable compound is preferably capable of forming a 5-membered ring structure, and more preferably capable of forming a 5-membered ring ether structure.

[0071] The cyclopolymerizable compound has a photocurable functional group. The cyclopolymerizable compound is a compound having a photocurable functional group and a cyclopolymerizable group. The cyclopolymerizable compound is a cyclopolymerizable photocurable compound. In the cyclopolymerizable compound, the photocurable functional group may be a part of the cyclopolymerizable group or may be a side chain of the cyclopolymerizable group. In the cyclopolymerizable compound, the photocurable functional group and the cyclopolymerizable group may share some atoms or some skeletons.

[0072] The cyclopolymerizable compound may have 1, 2, 2 or more, 3 or more, 4 or more, 5 or more, or 6 or more cyclopolymerizable groups. The cyclopolymerizable compound may have 12 or less, 8 or less, or 6 or less cyclopolymerizable groups.

[0073] From the viewpoint of more effectively exerting the effects of the present invention, the cyclopolymerizable compound preferably includes a photocurable compound having one cyclopolymerizable group. From the viewpoints of further enhancing the photocurability of the curable composition, favorably forming partition walls having a larger aspect ratio, increasing the glass transition temperature (Tg) of the cured product of the curable composition, and further improving the thermal cycle properties (particularly, crack suppression properties) of the cured product of the curable composition, the cyclopolymerizable compound preferably includes a photocurable compound having two or more cyclopolymerizable groups.

[0074] The cyclopolymerizable compound may have one or more photocurable functional groups. The photocurable functional group in the cyclopolymerizable compound may be a group that does not undergo cyclopolymerization, or may be a group that is not included in a ring structure after cyclization (a group that does not form a ring structure after cyclization). When the cyclopolymerizable compound has a photocurable functional group, the cyclopolymerizable compound may have one photocurable functional group, two photocurable functional groups, two or more photocurable functional groups, three or more photocurable functional groups, four or more photocurable functional groups, or five or more photocurable functional groups. The cyclopolymerizable compound may have 10 or less photocurable functional groups. From the viewpoint of more effectively exhibiting the effects of the present invention, it is preferable that the cyclopolymerizable compound includes a photocurable compound having one photocurable functional group. From the viewpoints of further enhancing the photocurability of the curable composition, favorably forming partition walls having a larger aspect ratio, increasing the glass transition temperature (Tg) of the cured product of the curable composition, and further enhancing the thermal cycle properties (particularly, crack suppression properties) of the cured product of the curable composition, it is preferable that the cyclopolymerizable compound includes a photocurable compound having two or more photocurable functional groups.

[0075] Examples of the cyclopolymerizable group, the group containing the cyclopolymerizable group, or the photocurable functional group include a (meth)acryloyl group, an α-(allyloxymethyl)acryloyl group, and a vinyl group.

[0076] From the viewpoint of enhancing cyclopolymerizability, the cyclopolymerizable group or the group containing the cyclopolymerizable group of the cyclopolymerizable compound is preferably a (meth)acryloyl group or an α-(allyloxymethyl)acryloyl group. From the viewpoint of enhancing photocurability of the curable composition, the photocurable functional group of the cyclopolymerizable compound is preferably a (meth)acryloyl group or an α-(allyloxymethyl)acryloyl group. From the viewpoint of enhancing cyclopolymerizability and photocurability, the cyclopolymerizable compound preferably has a (meth)acryloyl group or an α-(allyloxymethyl)acryloyl group.

[0077] The cyclopolymerizable compound may have one (meth)acryloyl group or α-(allyloxymethyl)acryloyl group, two (meth)acryloyl groups or α-(allyloxymethyl)acryloyl groups, or two or more (meth)acryloyl groups or α-(allyloxymethyl)acryloyl groups. The cyclopolymerizable compound may have three or more (meth)acryloyl groups or α-(allyloxymethyl)acryloyl groups, four or more (meth)acryloyl groups or α-(allyloxymethyl)acryloyl groups, or five or more (meth)acryloyl groups or α-(allyloxymethyl)acryloyl groups. The cyclopolymerizable compound may have 10 or less (meth)acryloyl groups or α-(allyloxymethyl)acryloyl groups. In this specification, when a cyclopolymerizable compound has three or more (meth)acryloyl groups, the compound having a cyclopolymerizable group having three or more (meth)acryloyl groups is classified as (A1) a first photocurable compound.

[0078] The cyclopolymerizable compound may be a monofunctional (meth)acrylate or a monofunctional α-(allyloxymethyl)acrylic acid, or may be a polyfunctional (meth)acrylate or a polyfunctional α-(allyloxymethyl)acrylic acid. From the viewpoints of further improving the cyclopolymerizability, further improving the photocurability, and favorably forming partition walls with a larger aspect ratio, the cyclopolymerizable compound preferably contains a polyfunctional (meth)acrylate or a polyfunctional α-(allyloxymethyl)acrylic acid. The cyclopolymerizable compound may contain a bifunctional (meth)acrylate compound or a bifunctional α-(allyloxymethyl)acrylic acid, or may contain a trifunctional (meth)acrylate compound or a trifunctional α-(allyloxymethyl)acrylic acid. The cyclopolymerizable compound may contain a tetrafunctional (meth)acrylate compound or a tetrafunctional α-(allyloxymethyl)acrylic acid, or may contain a pentafunctional (meth)acrylate compound or a pentafunctional α-(allyloxymethyl)acrylic acid. The cyclopolymerizable compound may contain a hexafunctional (meth)acrylate compound or a hexafunctional α-(allyloxymethyl)acrylic acid, or may contain a heptafunctional or higher (meth)acrylate compound or a heptafunctional or higher α-(allyloxymethyl)acrylic acid. The cyclopolymerizable compound may contain a decafunctional or lower (meth)acrylate compound or a decafunctional or lower α-(allyloxymethyl)acrylic acid.

[0079] Examples of the monofunctional (meth)acrylate or monofunctional α-(allyloxymethyl)acrylic acid include methyl-2-(allyloxymethyl)acrylic acid, 2-methoxyethyl-2-(allyloxymethyl)acrylic acid, tetrahydrofuran-2-ylmethyl-2-(allyloxymethyl)acrylic acid, 2-phenoxyethyl-2-(allyloxymethyl)acrylic acid, cyclohexyl-2-(allyloxymethyl)acrylic acid, and isobornyl-2-(allyloxymethyl)acrylic acid.

[0080] Examples of the bifunctional (meth)acrylate or bifunctional α-(allyloxymethyl)acrylic acid include tripropylene glycol di-2-(allyloxymethyl)acrylic acid, 1,6-hexanediol di-2-(allyloxymethyl)acrylic acid, neopentyl glycol di-2-(allyloxymethyl)acrylic acid, and tricyclodecane dimethanol di-2-(allyloxymethyl)acrylic acid.

[0081] Examples of the trifunctional (meth)acrylate or trifunctional α-(allyloxymethyl)acrylic acid include trimethylolpropane tri-2-(allyloxymethyl)acrylic acid.

[0082] Examples of the hexafunctional (meth)acrylate or hexafunctional α-(allyloxymethyl)acrylic acid include dipentaerythritol hexa-2-(allyloxymethyl)acrylic acid.

[0083] From the viewpoint of more effectively exerting the effects of the present invention, the cyclopolymerizable compound preferably has two or more carbon-carbon double bonds, and may have 12 or less, 8 or less, or 6 or less carbon-carbon double bonds.

[0084] From the viewpoint of more effectively exhibiting the effects of the present invention, the cyclopolymerizable compound preferably has an allyl ether group. From the viewpoint of more effectively exhibiting the effects of the present invention, the cyclopolymerizable group in the cyclopolymerizable compound is preferably an allyl ether group.

[0085] The cyclopolymerizable group or the group containing the cyclopolymerizable group is preferably a vinyl group, a (meth)acryloyl group, or an α-(allyloxymethyl)acryloyl group, more preferably a (meth)acryloyl group or an α-(allyloxymethyl)acryloyl group. The photocurable functional group is preferably a vinyl group, a (meth)acryloyl group, or an α-(allyloxymethyl)acryloyl group, more preferably a (meth)acryloyl group or an α-(allyloxymethyl)acryloyl group. The cyclopolymerizable compound preferably has a vinyl group, a (meth)acryloyl group, or an α-(allyloxymethyl)acryloyl group, more preferably a (meth)acryloyl group or an α-(allyloxymethyl)acryloyl group. In these cases, partition walls with a larger aspect ratio can be successfully formed, and the thermal cycling properties of the cured product of the curable composition can be further improved, thereby further increasing reflow resistance.

[0086] In order to more effectively exert the effects of the present invention, the cyclopolymerizable compound preferably has a structure represented by the following formula (1).

[0087] [ka]

[0088] In formula (1), R represents an organic group having 1 to 200 carbon atoms.

[0089] When the cyclopolymerizable compound has a structure represented by the formula (1), the cyclopolymerizable compound can form a polymer having a five-membered ring ether structure in the main chain by radical polymerization.

[0090] In the above formula (1), the number of carbon atoms in R is 1 or more and 200 or less, preferably 150 or less, and more preferably 100 or less. In the above formula (1), R is preferably an alkyl group. In the above formula (1), R may be a linear alkyl group, a branched alkyl group, or a cyclic alkyl group. In the above formula (1), R may contain an ether bond.

[0091] In the above formula (1), examples of R 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, an isobutyl group, a phenyl group, a pentyl group, a vinyl group, an allyl group, a crotyl group, a cyclopropyl group, a cyclobutyl group, a cyclohexyl group, a tetrahydrofurfuryl group, a methoxymethyl group, a methoxyethyl group, an ethoxymethyl group, an ethoxyethyl group, a phenoxyethyl group, a vinyloxyethyl group, an epoxy group, an isobornyl group, an adamantyl group, a dicyclopentadienyl group, and an oxetanyl group.

[0092] From the viewpoint of good ejection of the curable composition using an inkjet device, in the above formula (1), R is preferably a methyl group or an ethyl group, and more preferably a methyl group.

[0093] The cyclopolymerizable compound may have an alicyclic skeleton. The cyclopolymerizable compound may be a cyclopolymerizable compound having an alicyclic skeleton. The cyclopolymerizable compound may have a cyclopolymerizable group and an alicyclic skeleton. When the curable composition for inkjet contains a compound having a cyclopolymerizable group and an alicyclic skeleton, the compound having a cyclopolymerizable group and an alicyclic skeleton is classified as the cyclopolymerizable compound.

[0094] Examples of the cyclopolymerizable compound having an alicyclic skeleton include cyclohexyl-2-(allyloxymethyl)acrylic acid, isobornyl-2-(allyloxymethyl)acrylic acid, and tricyclodecane dimethanol di-2-(allyloxymethyl)acrylic acid.

[0095] In order to more effectively exert the effects of the present invention, the cyclopolymerizable compound preferably contains methyl-2-(allyloxymethyl)acrylic acid (that is, methyl 2-(allyloxymethyl)acrylate).

[0096] The content of the (A) photocurable compound in 100% by weight of the curable composition is preferably 4% by weight or more, more preferably 5% by weight or more, even more preferably 10% by weight or more, particularly preferably 15% by weight or more, and is preferably 90% by weight or less, more preferably 80% by weight or less, even more preferably 75% by weight or less, particularly preferably 70% by weight or less. When the content of the (A) photocurable compound is above the above-mentioned lower limit, the curing rate (reaction probability) of the curable composition can be increased, thereby suppressing the wetting and spreading of the B-staged product when curing the curable composition layer to obtain a B-staged product, and allowing for the successful formation of a cured product layer with an even higher aspect ratio. When the content of the (A) photocurable compound is below the above-mentioned upper limit, the photocuring shrinkage and thermal stress of the curable composition can be suppressed, thereby further improving the thermal cycle properties (particularly crack suppression) of the cured product of the curable composition. In addition, when the (A) photocurable compound contains the (A2) second photocurable compound, the content of the (A) photocurable compound indicates the total content of the (A1) first photocurable compound and the (A2) second photocurable compound (the same applies hereinafter).

[0097] The content of the (A1) first photocurable compound, based on 100% by weight of the curable composition, is preferably 0.5% by weight or more, more preferably 1% by weight or more, even more preferably 3% by weight or more, and preferably 30% by weight or less, more preferably 20% by weight or less, even more preferably 15% by weight or less, and particularly preferably 10% by weight or less. When the content of the (A1) first photocurable compound is above the above-mentioned lower limit and below the above-mentioned upper limit, the effects of the present invention can be more effectively exhibited. Specifically, when the content of the (A1) first photocurable compound is above the above-mentioned lower limit, the curing rate (reaction probability) of the curable composition can be increased, thereby suppressing the wetting and spreading of the B-staged product when curing the curable composition layer to obtain a B-staged product, and thereby enabling the formation of a cured product layer with a higher aspect ratio. When the content of the (A1) first photocurable compound is below the above-mentioned upper limit, the photocuring shrinkage and thermal stress of the curable composition can be suppressed, thereby further improving the thermal cycle properties (particularly, crack suppression) of the cured product of the curable composition.

[0098] When the (A) photocurable compound includes the (A2) second photocurable compound, the content of the (A2) second photocurable compound in 100% by weight of the curable composition is preferably 10% by weight or more, more preferably 20% by weight or more, even more preferably 30% by weight or more, and particularly preferably 40% by weight or more. When the (A) photocurable compound includes the (A2) second photocurable compound, the content of the (A2) second photocurable compound in 100% by weight of the curable composition is preferably 90% by weight or less, more preferably 80% by weight or less, and even more preferably 70% by weight or less. When the content of the (A2) second photocurable compound is equal to or greater than the above lower limit and equal to or less than the above upper limit, partition walls with an even larger aspect ratio can be successfully formed.

[0099] In 100% by weight of the curable composition, the total content of the first photocurable compound (A1) and the second photocurable compound (A2) is preferably 10% by weight or more, more preferably 20% by weight or more, even more preferably 40% by weight or more, and is preferably 95% by weight or less, more preferably 90% by weight or less, even more preferably 80% by weight or less. When the total content of the first photocurable compound (A1) and the second photocurable compound (A2) is not less than the above lower limit and not more than the above upper limit, partition walls with an even larger aspect ratio can be successfully formed.

[0100] When the (A2) second photocurable compound contains the cyclopolymerizable compound, the content of the cyclopolymerizable compound in 100% by weight of the curable composition is preferably 10% by weight or more, more preferably 15% by weight or more, and even more preferably 20% by weight or more. When the (A2) second photocurable compound contains the cyclopolymerizable compound, the content of the cyclopolymerizable compound in 100% by weight of the curable composition is preferably 80% by weight or less, more preferably 70% by weight or less, even more preferably 65% ​​by weight or less, particularly preferably 60% by weight or less, and most preferably 50% by weight or less. When the content of the cyclopolymerizable compound is equal to or greater than the above lower limit and equal to or less than the above upper limit, partition walls with a higher aspect ratio can be successfully formed. Furthermore, when the content of the cyclopolymerizable compound is equal to or greater than the above lower limit, the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition can be further improved.

[0101] The content of the first photocurable compound (A1) in 100% by weight of the photocurable compound (A) is preferably 0.5% by weight or more, more preferably 1.0% by weight or more, even more preferably 1.5% by weight or more, and is preferably 50% by weight or less, more preferably 40% by weight or less, even more preferably 30% by weight or less, and particularly preferably 20% by weight or less. When the content of the first photocurable compound (A1) is equal to or greater than the above-mentioned lower limit and equal to or less than the above-mentioned upper limit, the effects of the present invention can be more effectively exhibited. Specifically, when the content of the first photocurable compound (A1) is equal to or greater than the above-mentioned lower limit, the curing rate (reaction probability) of the curable composition can be increased, and therefore, when curing of the curable composition layer to obtain a B-staged product can be promoted, wetting and spreading of the B-staged product can be suppressed, and a cured product layer with an even larger aspect ratio can be successfully formed. When the content of the (A1) first photocurable compound is equal to or less than the above upper limit, photocuring shrinkage and thermal stress of the curable composition can be suppressed, and therefore the thermal cycle properties (particularly crack suppression properties) of the cured product of the curable composition can be further improved.

[0102] The content of the (A2) second photocurable compound, based on 100% by weight of the (A) photocurable compound, is preferably 40% by weight or more, more preferably 50% by weight or more, even more preferably 60% by weight or more, and particularly preferably 70% by weight or more, and is preferably 99.9% by weight or less, more preferably 95% by weight or less, and even more preferably 90% by weight or less. When the content of the (A2) second photocurable compound is equal to or greater than the above-mentioned lower limit and equal to or less than the above-mentioned upper limit, a cured product layer with an even higher aspect ratio can be successfully formed. Furthermore, when the content of the (A2) second photocurable compound is equal to or greater than the above-mentioned lower limit and equal to or less than the above-mentioned upper limit, deformation due to cure shrinkage of the curable composition can be further suppressed, and the thermal cycle resistance (particularly crack suppression) of the cured product of the curable composition can be further improved.

[0103] <(B) Photopolymerization initiator> The curable composition contains a photopolymerization initiator (B). The photopolymerization initiator (B) may be used alone or in combination of two or more kinds.

[0104] Examples of the (B) photopolymerization initiator include a photoradical polymerization initiator and a photocationic polymerization initiator, etc. From the viewpoint of favorably forming partition walls having a larger aspect ratio, the (B) photopolymerization initiator is preferably a photoradical polymerization initiator.

[0105] The photoradical 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-hydroxycyclohexyl phenyl ketone and 2-hydroxy-2-methylpropiophenone; acetophenone compounds such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, and 1,1-dichloroacetophenone; 2-methyl-1-[4-(methylthiphenone)]- ... (o)phenyl]-2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, 2-(dimethylamino)-2-(4-methylbenzyl)-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-(4- Aminoacetophenone compounds such as morpholinophenyl)-2-benzyl-1-butanone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, and N,N-dimethylaminoacetophenone; anthraquinone compounds such as 2-methylanthraquinone, 2-ethylanthraquinone, and 2-t-butylanthraquinone; thioxanthone compounds such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, and 2,4-diisopropylthioxanthone; acetophenone dimethicone Ketal compounds such as ethyl ketal and benzyl dimethyl ketal; acylphosphine oxide compounds such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; oxime ester compounds such as 1,2-octanedione, 1-[4-(phenylthio)-2-(o-benzoyloxime)], ethanone, and 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-1-(o-acetyloxime);Examples of the photo-radical polymerization initiator include titanocene compounds such as bis(cyclopentadienyl)-diphenyl-titanium, bis(cyclopentadienyl)-dichloro-titanium, bis(cyclopentadienyl)-bis(2,3,4,5,6-pentafluorophenyl)titanium, and bis(cyclopentadienyl)-bis(2,6-difluoro-3-(pyrrol-1-yl)phenyl)titanium. The photo-radical polymerization initiator may be used alone or in combination of two or more.

[0106] From the viewpoint of more effectively exerting the effects of the present invention and forming a cured layer with higher precision, it is preferable that the (B) photopolymerization initiator contains 2-(dimethylamino)-2-(4-methylbenzyl)-1-(4-morpholinophenyl)butan-1-one.

[0107] A photopolymerization initiation aid may be used together with the photoradical polymerization 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.

[0108] Furthermore, titanocene compounds such as CGI-784 (manufactured by Ciba Specialty Chemicals) that absorb light in the visible light region may be used to promote the photoreaction.

[0109] Examples of the photocationic polymerization initiator include sulfonium salts, iodonium salts, metallocene compounds, benzoin tosylate, etc. The photocationic polymerization initiator may be used alone or in combination of two or more.

[0110] From the viewpoint of more efficiently exerting the effects of the present invention, the content of the (B) 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 is preferably 20% by weight or less, more preferably 15% by weight or less.

[0111] From the viewpoint of more efficiently exerting the effects of the present invention, the content of the (B) photopolymerization initiator is preferably 5 parts by weight or more, more preferably 10 parts by weight or more, and preferably 30 parts by weight or less, more preferably 25 parts by weight or less, relative to 100 parts by weight of the (A) photocurable compound.

[0112] From the viewpoint of more efficiently exerting the effects of the present invention, the content of the (B) photopolymerization initiator is preferably 3 parts by weight or more, more preferably 5 parts by weight or more, and preferably 25 parts by weight or less, more preferably 20 parts by weight or less, relative to 100 parts by weight of the (A1) first photocurable compound.

[0113] From the viewpoint of more efficiently exerting the effects of the present invention, the content of the (B) photopolymerization initiator is preferably 5 parts by weight or more, more preferably 10 parts by weight or more, and preferably 30 parts by weight or less, more preferably 25 parts by weight or less, relative to 100 parts by weight of the cyclopolymerizable compound.

[0114] <(C) Rubber particles> The curable composition contains (C) rubber particles. The (C) rubber particles are core-shell particles having a core and a shell disposed on the surface of the core. The (C) rubber particles are core-shell type rubber particles. The (C) rubber particles are rubber particles having a core-shell structure. Since the curable composition contains the (C) rubber particles, the curable composition can reduce the elastic modulus of the cured product of the curable composition and increase the toughness of the cured product of the curable composition, thereby improving the thermal cycle properties (particularly crack suppression) of the cured product of the curable composition. Only one type of (C) rubber particle may be used, or two or more types may be used in combination.

[0115] The (C) rubber particles contain rubber. In the (C) rubber particles, the core may contain rubber, and the shell may contain rubber. In the (C) rubber particles, the core and the shell may contain rubber. From the viewpoint of further improving the thermal cycling properties (particularly crack suppression properties) of the cured product of the curable composition, it is preferable that the core contains rubber.

[0116] Examples of the rubber include silicone rubber, polybutadiene rubber, acrylic rubber, and styrene butadiene rubber. The rubber may be used alone or in combination of two or more.

[0117] From the viewpoint of further improving the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition, the (C) rubber particles preferably contain silicone rubber, polybutadiene rubber, or acrylic rubber, and more preferably contain silicone rubber or polybutadiene rubber. From the viewpoint of further improving the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition, the (C) rubber particles are preferably silicone-based core-shell rubber particles, polybutadiene-based core-shell rubber particles, or acrylic-based core-shell rubber particles. From the viewpoint of further improving the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition, the (C) rubber particles are more preferably silicone-based core-shell rubber particles or polybutadiene-based core-shell rubber particles.

[0118] Examples of the silicone-based core-shell rubber particles include silicone-acrylate-methyl methacrylate copolymer resin particles and silicone-acrylate-acrylonitrile-styrene copolymer resin particles. Examples of the polybutadiene-based core-shell rubber particles include methyl methacrylate-butadiene-styrene copolymer resin (MBS resin) particles and acrylonitrile-butadiene-styrene copolymer resin (ABS resin) particles. Examples of the acrylic-based core-shell rubber particles include acrylate-styrene-acrylonitrile copolymer resin (ASA resin) particles and acrylate-methyl methacrylate copolymer resin particles. The (C) rubber particles may also be modified with maleic anhydride, glycidyl methacrylate, or the like.

[0119] From the viewpoint of further improving the thermal cycle properties (particularly, crack suppression properties) of the cured product of the curable composition, the core material preferably contains silicone rubber, butadiene rubber, or acrylic rubber, and more preferably contains silicone rubber or butadiene rubber.

[0120] Materials for the shell include acrylic resin and epoxy resin.

[0121] From the viewpoint of further improving the thermal cycle properties (particularly crack suppression properties) of the cured product of the curable composition, the shell material preferably contains an acrylic resin or an epoxy resin, more preferably contains an acrylic resin, and further preferably contains a polymethyl methacrylate resin (PMMA).

[0122] The method for producing the (C) rubber particles is not particularly limited, and examples of the method for producing the (C) rubber particles include emulsion polymerization.

[0123] As the (C) rubber particles, commercially available products may be used.

[0124] The (C) rubber particles may be spherical, or may have a shape other than spherical, such as a flat shape.

[0125] The particle diameter of the (C) rubber particles is preferably 50 nm or more, more preferably 100 nm or more, even more preferably 200 nm or more, and preferably 800 nm or less, more preferably 600 nm or less. When the particle diameter of the (C) rubber particles is equal to or greater than the above-mentioned lower limit, the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition can be further improved. When the particle diameter of the (C) rubber particles is equal to or less than the above-mentioned upper limit, the curable composition can be efficiently ejected using an inkjet device, and a cured product layer with an even larger aspect ratio can be efficiently formed.

[0126] The particle size of the (C) rubber particles refers to the diameter when the (C) rubber particles are spherical, and refers to the maximum diameter when the (C) rubber particles are other than spherical. The particle size of the (C) rubber particles is preferably the average particle size. The average particle size of the (C) rubber particles can be measured using a particle size measuring device. Examples of the particle size measuring device include a particle size distribution measuring device that uses the principles of laser light scattering, electrical resistance change, and image analysis after imaging.

[0127] The average particle size of the (C) rubber particles is preferably a volume average particle size. The volume average particle size is the average particle size measured on a volume basis, and is the median diameter (D50) at 50%. The volume average particle size (D50) can be measured by a laser diffraction / scattering method, an image analysis method, the Coulter method, a centrifugal sedimentation method, or the like. The volume average particle size (D50) is preferably measured by a laser diffraction / scattering method.

[0128] The particle diameter of the core is preferably 50 nm or more, more preferably 300 nm or more, and preferably 1000 nm or less, more preferably 500 nm or less. When the particle diameter of the core is equal to or greater than the lower limit, the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition can be further improved. When the particle diameter of the core is equal to or less than the upper limit, the curable composition can be efficiently ejected using an inkjet device, and a cured product layer with a larger aspect ratio can be efficiently formed.

[0129] The particle size of the core refers to the diameter when the core is spherical, and refers to the maximum diameter when the core is other than spherical. The particle size of the core is preferably the average particle size. The average particle size of the core can be measured using a particle size measuring device. Examples of the particle size measuring device include a particle size distribution measuring device that uses the principles of laser light scattering, electrical resistance change, and image analysis after imaging.

[0130] The thickness of the shell is preferably 50 nm or more, more preferably 300 nm or more, and preferably 1000 nm or less, more preferably 500 nm or less. When the thickness of the shell is equal to or greater than the lower limit, the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition can be further improved. When the thickness of the shell is equal to or less than the upper limit, the curable composition can be efficiently ejected using an inkjet device, and a cured product layer with a larger aspect ratio can be efficiently formed.

[0131] The glass transition temperature of the (C) rubber particles is preferably -30°C or lower, more preferably -80°C or lower, and even more preferably -100°C or lower. When the glass transition temperature of the (C) rubber particles is equal to or lower than the above upper limit, the thermal cycling properties (particularly, crack suppression properties) of the cured product of the curable composition can be further improved. The lower limit of the glass transition temperature of the (C) rubber particles is not particularly limited, and the lower the glass transition temperature, the more the thermal cycling properties (particularly, crack suppression properties) of the cured product of the curable composition can be further improved. The glass transition temperature of the (C) rubber particles may be -1000°C or higher. The glass transition temperature of the (C) rubber particles is preferably the glass transition temperature of the rubber component, and the glass transition temperature of the (C) rubber particles is preferably the glass transition temperature of the core.

[0132] The content of the (C) rubber particles in 100% by weight of the curable composition is preferably 1% by weight or more, more preferably 3% by weight or more, even more preferably 5% by weight or more, and preferably 30% by weight or less, more preferably 20% by weight or less, even more preferably 15% by weight or less, and particularly preferably 10% by weight or less. When the content of the (C) rubber particles is above the above lower limit, the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition can be further improved. When the content of the (C) rubber particles is below the above upper limit, the curable composition can be efficiently ejected using an inkjet device, and a cured product layer with an even larger aspect ratio can be successfully formed.

[0133] The content of the (C) rubber particles is preferably 5 parts by weight or more, more preferably 8 parts by weight or more, and preferably 20 parts by weight or less, more preferably 17 parts by weight or less, per 100 parts by weight of the (A) photocurable compound. When the content of the (C) rubber particles is equal to or greater than the above-mentioned lower limit, the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition can be further improved. When the content of the (C) rubber particles is equal to or less than the above-mentioned upper limit, the curable composition can be efficiently ejected using an inkjet device, and a cured product layer with an even larger aspect ratio can be efficiently formed.

[0134] The content of the (C) rubber particles is preferably 60 parts by weight or more, more preferably 100 parts by weight or more, and preferably 240 parts by weight or less, more preferably 200 parts by weight or less, per 100 parts by weight of the (A1) first photocurable compound. When the content of the (C) rubber particles is equal to or greater than the above-mentioned lower limit, the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition can be further improved. When the content of the (C) rubber particles is equal to or less than the above-mentioned upper limit, the curable composition can be efficiently ejected using an inkjet device, and a cured product layer with an even larger aspect ratio can be efficiently formed.

[0135] The content of the (C) rubber particles is preferably 7 parts by weight or more, more preferably 11 parts by weight or more, and preferably 27 parts by weight or less, more preferably 22 parts by weight or less, relative to 100 parts by weight of the cyclopolymerizable compound. When the content of the (C) rubber particles is equal to or greater than the lower limit, the thermal cycling properties (particularly crack suppression) of the cured product of the curable composition can be further improved. When the content of the (C) rubber particles is equal to or less than the upper limit, the curable composition can be efficiently ejected using an inkjet device, and a cured product layer with an even larger aspect ratio can be efficiently formed.

[0136] <(D) Thermosetting compound> The curable composition may or may not contain a (D) thermosetting compound. The (D) thermosetting compound is a compound that can be thermoset. The (D) thermosetting compound has a thermosetting functional group. Only one (D) thermosetting compound may be used, or two or more (D) thermosetting compounds may be used in combination.

[0137] (D) Examples of the thermosetting compound include a thermosetting compound having a maleimide group, a thermosetting compound having a cyclic ether group, a thermosetting compound having a cyclic thioether group, a thermosetting compound having a thiirane group, and a thermosetting compound having a vinyl group.

[0138] From the viewpoint of enhancing thermosetting properties, the (D) thermosetting compound preferably has a cyclic ether group or a cyclic thioether group, and more preferably has an epoxy group. From the viewpoint of enhancing thermosetting properties, the (D) thermosetting compound preferably contains a thermosetting compound having a cyclic ether group or a thermosetting compound having a cyclic thioether group. From the viewpoint of enhancing thermosetting properties, the (D) thermosetting compound more preferably contains an epoxy compound.

[0139] Examples of the epoxy compound include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, phenol novolac type epoxy compounds, cresol novolac type epoxy compounds, biphenyl type epoxy compounds, biphenyl novolac type epoxy compounds, biphenol type epoxy compounds, naphthalene type epoxy compounds, fluorene type epoxy compounds, phenol aralkyl type epoxy compounds, naphthol aralkyl type epoxy compounds, dicyclopentadiene type epoxy compounds, anthracene type epoxy compounds, epoxy compounds having an adamantane skeleton, epoxy compounds having a tricyclodecane skeleton, naphthylene ether type epoxy compounds, and epoxy compounds having a triazine nucleus in the skeleton.

[0140] The epoxy compound may be a glycidyl ether type epoxy compound. The glycidyl ether type epoxy compound is an epoxy compound having at least one glycidyl ether group. The epoxy compound may also be a glycidyl amine type epoxy compound. The glycidyl amine type epoxy compound is an epoxy compound having at least one glycidyl amine group.

[0141] From the viewpoint of increasing the adhesive strength between the substrate and the cured product of the curable composition and further improving the thermal cycle properties (particularly, the ability to inhibit peeling) of the cured product of the curable composition, the (D) thermosetting compound preferably has an aromatic skeleton, and is more preferably a bisphenol A type epoxy compound or a bisphenol F type epoxy compound.

[0142] The (D) thermosetting compound may or may not have a (meth)acryloyl group. The (D) thermosetting compound may contain a thermosetting compound having a (meth)acryloyl group, or may not contain a thermosetting compound having a (meth)acryloyl group. When the (D) thermosetting compound has a photocurable functional group such as a (meth)acryloyl group, the thermosetting compound having the photocurable functional group corresponds to a component having a photocurable functional group.

[0143] The (D) thermosetting compound having a (meth)acryloyl group is a photo- and thermosetting compound.

[0144] Examples of the photo- and thermosetting compounds include glycidyl (meth)acrylate and 4-hydroxybutyl (meth)acrylate glycidyl ether.

[0145] The content of the (D) thermosetting compound in 100% by weight of the curable composition is preferably 5% by weight or more, more preferably 10% by weight or more, even more preferably 15% by weight or more, and preferably 45% by weight or less, more preferably 40% by weight or less, even more preferably 35% by weight or less, and particularly preferably 30% by weight or less. When the content of the (D) thermosetting compound is at least the above-mentioned lower limit, the adhesive strength between the substrate and the cured product of the curable composition can be increased, and the thermal cycling characteristics (particularly the ability to suppress peeling) of the cured product of the curable composition can be further improved. When the content of the (D) thermosetting compound is at most the above-mentioned upper limit, the photocurability of the curable composition can be further improved, and partition walls with an even larger aspect ratio can be successfully formed.

[0146] The content of the (D) thermosetting compound is preferably 10 parts by weight or more, more preferably 15 parts by weight or more, and even more preferably 20 parts by weight or more, and is preferably 65 parts by weight or less, more preferably 55 parts by weight or less, and even more preferably 50 parts by weight or less, relative to 100 parts by weight of the (A) photocurable compound. When the content of the (D) thermosetting compound is at least the above-mentioned lower limit, the adhesive strength between the substrate and the cured product of the curable composition can be increased, and the thermal cycling characteristics (particularly, the ability to suppress peeling) of the cured product of the curable composition can be further improved. When the content of the (D) thermosetting compound is at most the above-mentioned upper limit, the photocurability of the curable composition can be further improved, and partition walls with an even larger aspect ratio can be successfully formed.

[0147] The content of the (D) thermosetting compound is preferably 10 parts by weight or more, more preferably 20 parts by weight or more, even more preferably 30 parts by weight or more, and preferably 150 parts by weight or less, more preferably 100 parts by weight or less, and even more preferably 50 parts by weight or less, per 100 parts by weight of the (A1) first photocurable compound. When the content of the (D) thermosetting compound is at least the above-mentioned lower limit, the adhesive strength between the substrate and the cured product of the curable composition can be increased, and the thermal cycling characteristics (particularly, the ability to suppress peeling) of the cured product of the curable composition can be further improved. When the content of the (D) thermosetting compound is at most the above-mentioned upper limit, the photocurability of the curable composition can be further improved, and partition walls with an even larger aspect ratio can be successfully formed.

[0148] The content of the (D) thermosetting compound is preferably 25 parts by weight or more, more preferably 45 parts by weight or more, even more preferably 50 parts by weight or more, particularly preferably 60 parts by weight or more, and even more preferably 70 parts by weight or more, per 100 parts by weight of the (A) cyclopolymerizable compound. The content of the (D) thermosetting compound is preferably 600 parts by weight or less, more preferably 400 parts by weight or less, and even more preferably 200 parts by weight or less, per 100 parts by weight of the (A) cyclopolymerizable compound. When the content of the (D) thermosetting compound is equal to or greater than the above-mentioned lower limit, the adhesive strength between the substrate and the cured product of the curable composition can be increased, and the thermal cycling characteristics (particularly, the ability to suppress peeling) of the cured product of the curable composition can be further improved. When the content of the (D) thermosetting compound is equal to or less than the above-mentioned upper limit, the photocurability of the curable composition can be further improved, and partition walls with a larger aspect ratio can be successfully formed.

[0149] <(E) Heat curing agent> The curable composition may or may not contain a (E) thermosetting agent. The (E) thermosetting agent thermally cures the (D) thermosetting compound. Preferably, the curable composition further contains the (D) thermosetting compound and the (E) thermosetting agent.

[0150] Examples of the (E) heat curing agent include organic acids, amine compounds, amide compounds, hydrazide compounds, imidazole compounds, imidazoline compounds, phenol compounds, urea compounds, polysulfide compounds, and acid anhydrides. The (E) heat curing agent may also be a modified polyamine compound such as an amine-epoxy adduct. Only one (E) heat curing agent may be used, or two or more may be used in combination.

[0151] The amine compound refers to a compound having one or more primary, secondary, or tertiary amino groups. Examples of the amine compound include (1) aliphatic amines, (2) alicyclic amines, (3) aromatic amines, (4) hydrazides, and (5) guanidine derivatives. The amine compound may also be an adduct such as an epoxy compound-added polyamine (a reaction product of an epoxy compound and a polyamine), a Michael addition polyamine (a reaction product of an α,β-unsaturated ketone and a polyamine), a Mannich addition polyamine (a condensate of a polyamine with formalin and a phenol), a thiourea-added polyamine (a reaction product of a thiourea and a polyamine), or a ketone-blocked polyamine (a reaction product of a ketone compound and a polyamine [ketimine]).

[0152] Examples of the (1) aliphatic amine include diethylenetriamine, triethylenetetramine, tetraethylenepentamine, and diethylaminopropylamine.

[0153] Examples of the (2) alicyclic amine include menthenediamine, isophoronediamine, N-aminoethylpiperazine, 3,9-bis(3-aminopropyl)-2,4,8,10-tetraoxaspiro(5,5)undecane adduct, bis(4-amino-3-methylcyclohexyl)methane, and bis(4-aminocyclohexyl)methane.

[0154] Examples of the aromatic amines (3) include m-phenylenediamine, p-phenylenediamine, o-xylylenediamine, m-xylylenediamine, p-xylylenediamine, 4,4-diaminodiphenylmethane, 4,4-diaminodiphenylpropane, 4,4-diaminodiphenyl ether, 4,4-diamino-3,3-diethyl-5,5-dimethyldiphenylmethane, diphenylmethane, 4,4-diaminodicyclohexane, bis(4-aminophenyl)phenylmethane, 1,5-diaminonaphthalene, 1, Examples of such bis(4-aminophenyl)cyclohexane include 1-bis(4-aminophenyl)cyclohexane, 2,2-bis[(4-aminophenoxy)phenyl]propane, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4-methylene-bis(2-chloroaniline), and 4,4-diaminodiphenyl sulfone.

[0155] Examples of the hydrazide (4) include carbodihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, dodecanedioic acid dihydrazide, and isophthalic acid dihydrazide.

[0156] Examples of the guanidine derivative (5) include dicyandiamide, 1-o-tolyldiguanide, α-2,5-dimethylguanide, α,ω-diphenyldiguanidide, α,α-bisguanylguanidinodiphenyl ether, p-chlorophenyldiguanide, α,α-hexamethylenebis[ω-(p-chlorophenol)]diguanide, phenyldiguanide oxalate, acetylguanidine, and diethylcyanoacetylguanidine.

[0157] Examples of the phenol compound include polyhydric phenol compounds, such as phenol, cresol, ethylphenol, butylphenol, octylphenol, bisphenol A, tetrabromobisphenol A, bisphenol F, bisphenol S, 4,4'-biphenylphenol, naphthalene skeleton-containing phenol novolac resins, xylylene skeleton-containing phenol novolac resins, dicyclopentadiene skeleton-containing phenol novolac resins, and fluorene skeleton-containing phenol novolac resins.

[0158] Examples of the acid anhydride include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylnadic anhydride, dodecylsuccinic anhydride, chlorendic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, methylcyclohexenetetracarboxylic anhydride, trimellitic anhydride, and polyazelaic anhydride.

[0159] From the viewpoint of excellent ejection of the curable composition using an inkjet device, it is preferable that the (E) thermosetting agent contains an aromatic amine. The aromatic amine may have one, two, two or more, or three or more benzene rings. The aromatic amine may have 10 or less benzene rings. The aromatic amine may have one, two, two or more, or three or more amino groups. The aromatic amine may have 10 or less amino groups. From the viewpoint of excellent ejection of the curable composition using an inkjet device, it is preferable that the aromatic amine has two or more benzene rings and two or more amino groups.

[0160] From the viewpoint of excellent ejection of the curable composition using an inkjet device, it is preferable that adjacent benzene rings in the aromatic amine are bonded to each other by an oxygen atom or a sulfur atom. From the viewpoint of excellent ejection of the curable composition using an inkjet device, it is preferable that adjacent benzene rings in the aromatic amine are bonded to each other by an ether bond or a thioether bond.

[0161] Examples of aromatic amines having two or more benzene rings and two or more amino groups, with adjacent benzene rings bonded by an oxygen atom or a sulfur atom, include bis[4-(3-aminophenoxy)phenyl]sulfone, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4-diaminodiphenyl sulfone, and 4,4-diaminodiphenyl ether. From the viewpoint of successfully discharging the curable composition using an inkjet device, the aromatic amine more preferably contains 1,3-bis(3-aminophenoxy)benzene or bis[4-(3-aminophenoxy)phenyl]sulfone, and even more preferably contains 1,3-bis(3-aminophenoxy)benzene. From the viewpoint of successfully ejecting the curable composition using an inkjet device, the (E) heat curing agent preferably contains 1,3-bis(3-aminophenoxy)benzene or bis[4-(3-aminophenoxy)phenyl]sulfone, and more preferably contains 1,3-bis(3-aminophenoxy)benzene.

[0162] The content of the (E) thermosetting agent in 100% by weight of the curable composition is preferably 1% by weight or more, more preferably 3% by weight or more, even more preferably 5% by weight or more, and preferably 30% by weight or less, more preferably 20% by weight or less, and even more preferably 10% by weight or less. When the content of the (E) thermosetting agent is equal to or greater than the above-mentioned lower limit, the adhesive strength between the substrate and the cured product of the curable composition can be increased, and the thermal cycling characteristics (particularly, the ability to suppress peeling) of the cured product of the curable composition can be further improved. When the content of the (E) thermosetting agent is equal to or less than the above-mentioned upper limit, the photocurability of the curable composition can be further improved, and partition walls with an even larger aspect ratio can be successfully formed.

[0163] The content of the (E) thermosetting agent is preferably 15 parts by weight or more, more preferably 20 parts by weight or more, even more preferably 30 parts by weight or more, and preferably 80 parts by weight or less, more preferably 70 parts by weight or less, and even more preferably 60 parts by weight or less, per 100 parts by weight of the (D) thermosetting compound. When the content of the (E) thermosetting agent is at least the above-mentioned lower limit, the adhesive strength between the substrate and the cured product of the curable composition can be increased, and the thermal cycling characteristics (particularly, the ability to suppress peeling) of the cured product of the curable composition can be further improved. When the content of the (E) thermosetting agent is at most the above-mentioned upper limit, the photocurability of the curable composition can be further improved, and partition walls with an even larger aspect ratio can be successfully formed.

[0164] <Curing accelerator> The curable composition may or may not contain a curing accelerator. The curing accelerator may be used alone or in combination of two or more.

[0165] Examples of the curing accelerator include tertiary amines, imidazoles, quaternary ammonium salts, quaternary phosphonium salts, organic metal salts, phosphorus compounds, and urea compounds.

[0166] The content of the curing accelerator in 100% by weight of the curable composition is preferably 0.01% by weight or more, more preferably 0.05% by weight or more, and preferably 10% by weight or less, more preferably 5% by weight or less.

[0167] <Solvent> The curable composition may or may not contain a solvent. The solvent may be used alone or in combination of two or more.

[0168] Examples of the solvent include water and organic solvents.

[0169] From the viewpoint of further enhancing the removability of residues, the solvent is preferably an organic solvent.

[0170] Examples of the organic solvent 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.

[0171] From the viewpoint of further increasing the thickness precision of the curable composition layer, the smaller the content of the solvent in the curable composition, the better.

[0172] When the curable composition contains the solvent, the content of the solvent in 100% by weight of the curable composition is preferably 5% by weight or less, more preferably 1% by weight or less, and even more preferably 0.5% by weight or less. Most preferably, the curable composition does not contain the solvent.

[0173] <Other ingredients> The curable composition may contain other components in addition to the above-mentioned components, such as a coupling agent, a filler, a leveling agent, a defoaming agent, and a polymerization inhibitor.

[0174] The curable composition can be used to form an air cavity. The curable composition can be used, in particular, to form an air cavity in an electronic component. The curable composition can be used to form a wall surrounding the air cavity (use of the curable composition to form a wall surrounding the air cavity). The curable composition can be used, in particular, to form a wall surrounding the air cavity in an electronic component (use of the curable composition to form a wall surrounding the air cavity in an electronic component).

[0175] (Electronic Components and Manufacturing Methods for Electronic Components) The electronic component according to the present invention includes a circuit board, an electronic member, and an adhesive. In the electronic component according to the present invention, the electronic member is mounted on the circuit board. In the electronic component according to the present invention, the adhesive is a cured product of the curable composition for inkjet printing and for forming an air cavity. In the electronic component according to the present invention, the adhesive contacts the upper surface of the circuit board and at least a portion of the side surface of the electronic member. In the electronic component according to the present invention, an air cavity is formed by the circuit board, the electronic member, and the adhesive.

[0176] The method for manufacturing an electronic component according to the present invention may include the following step (1). The method for manufacturing an electronic component according to the present invention also includes the following steps (2) and (3): (1) a step of mounting an electronic component on a circuit board; (2) a step of applying the above-mentioned inkjet and air cavity-forming curable composition to the upper surface of a circuit board having an electronic component mounted on its upper surface by an inkjet method to form a curable composition layer; and (3) a step of curing the curable composition layer to form an adhesive joint.

[0177] In the method for producing an electronic component, in the step (2) of forming a curable composition layer, the curable composition layer is formed so as to be in contact with at least a part of the side surface of the electronic member.

[0178] In the method for manufacturing an electronic component according to the present invention, an air cavity is formed by the circuit board, the electronic member, and the adhesive portion.

[0179] The electronic component and the method for manufacturing the electronic component have the above-mentioned configuration, and therefore can improve the thermal cycle characteristics of the electronic component and form adhesive joints with a large aspect ratio in the electronic component.

[0180] In the method for manufacturing an electronic component, in the step (2) of forming a curable composition layer (coating step), the curable composition is coated by an inkjet method (using an inkjet device), thereby improving the sealing of air cavities.

[0181] Specific embodiments of the present invention will be described below with reference to the drawings. Note that in the drawings, the size, thickness, shape, etc. may differ from the actual size, thickness, shape, etc. for the sake of convenience of illustration.

[0182] Fig. 1(a) is a plan view schematically showing an electronic component according to a first embodiment of the present invention, and Fig. 1(b) is a cross-sectional view schematically showing the electronic component, taken along line II in Fig. 1(a).

[0183] The electronic component 10 shown in FIG. 1 includes a circuit board 1, an electronic component 2, an adhesive portion 3, and a molded resin portion 44. The electronic component 2 has solder balls 41, a resin sheet 42, and connection terminals 43 (not shown in FIG. 1(a)). One electronic component 2 is mounted in the electronic component 10. The electronic component 10 includes one electronic component 2. The adhesive portion 3 is a cured product of a curable composition that is liquid at 23°C. The adhesive portion 3 is a photo- and thermally cured product of the curable composition. The adhesive portion 3 is in contact with the upper surface of the circuit board 1 and a portion of the side surface of the electronic component 2. The adhesive portion 3 is in contact with a portion of the upper surface of the circuit board 1, and is in contact with a portion of the side surface and the entire upper surface of the electronic component 2. The adhesive portion 3 is not in contact with the lower surface of the electronic component 2. The adhesive portion 3 bonds the upper surface of the circuit board 1 to the side and upper surface of the electronic component 2. The adhesive portion 3 is disposed on the upper surface of the circuit board 1. The adhesive portion 3 is arranged on the side surface of the electronic component 2 and also on the top surface of the electronic component 2. The adhesive portion 3 is arranged on part of the top surface of the circuit board 1, and on part of the side surface and the entire top surface of the electronic component 2. The adhesive portion 3 is not arranged on the bottom surface of the electronic component 2. An air cavity R is formed by the circuit board 1, the electronic component 2, and the adhesive portion 3. The molded resin portion 44 is arranged on the top surface and side surface of the adhesive portion 3.

[0184] 1 has a significantly high sealing performance for the air cavity R. Furthermore, in the present invention, the molding material (the material of the molded resin portion) is less likely to infiltrate into the air cavity R.

[0185] In the electronic component 10, the electronic member 2 is a semiconductor chip. The electronic component 10 is a communication filter.

[0186] In the electronic component, the adhesive portion may or may not be in contact with the upper surface of the electronic member. In the electronic component, the adhesive portion may or may not be disposed on the upper surface of the electronic member. In the electronic component, the adhesive portion may or may not be in contact with the lower surface of the electronic member. In the electronic component, the adhesive portion may or may not be disposed on the lower surface of the electronic member. In the electronic component, the adhesive portion may or may not be in contact with the lower surface of the electronic member. In the electronic component, the adhesive portion may or may not be in contact with the lower surface of the electronic member but not with the side surface. In the electronic component, the adhesive portion may or may not be disposed on the lower surface of the electronic member but not with the side surface.

[0187] Figures 2(a) and (b) are cross-sectional views for explaining each step of the method for manufacturing the electronic component shown in Figure 1. Figures 3(c) and (d) are cross-sectional views for explaining each step of the method for manufacturing the electronic component shown in Figure 1. Figures 4(e) to (g) are cross-sectional views for explaining each step of the method for manufacturing the electronic component shown in Figure 1.

[0188] First, electronic components are mounted on a circuit board 1 (mounting step). Next, as shown in FIG. 2(a), an inkjet and air cavity-forming curable composition is applied to the upper surface (surface) of the circuit board 1 using an inkjet device (by an inkjet method) to form a curable composition layer 3A (application step). The curable composition is applied to the upper surface (surface) of the circuit board 1 to form a curable composition layer 3A. The curable composition is ejected from an ejection unit 51 of the inkjet device.

[0189] Next, as shown in Figures 2(b), 3(c) and (d), and 4(e) and (f), the curable composition layer 3A is cured to form the adhesive portion 3. Specifically, as shown in Figure 2(b), the curable composition layer 3A is irradiated with light from a light irradiation unit 52 of the inkjet device to promote curing of the curable composition layer 3A, thereby forming a B-staged product layer 3B (photocuring step). The B-staged product layer 3B is a pre-cured product layer of the curable composition.

[0190] In the method for producing an electronic component, the curable composition may be applied to a specific region, and then the entire applied curable composition may be irradiated with light to form a B-staged product layer. In the method for producing an electronic component, the applied curable composition may be irradiated with light every time multiple drops of the curable composition are applied, to form a B-staged product layer. In the method for producing an electronic component, the applied curable composition may be irradiated with light every time a single drop of the curable composition is applied, to form a B-staged product layer. That is, the applied curable composition may be irradiated with light every time multiple drops or a single drop of the curable composition are applied, to form a B-staged product layer. Therefore, the curable composition layer may be photocured every time multiple drops or a single drop of the curable composition are applied, to obtain multiple B-staged product layers.

[0191] In the method for manufacturing the electronic component, in the step of forming the curable composition layer 3A (coating step), the curable composition layer 3A is formed so as to contact at least a portion of the side surface of the electronic component 2, and in the step of forming the B-stage product layer 3B (photo-curing step), the B-stage product layer 3B is formed so as to contact at least a portion of the side surface of the electronic component 2 (see Figure 4(e)).

[0192] After the photocuring step, it is determined whether or not to repeat the coating step and the photocuring step. If the coating step and the photocuring step are repeated, the curable composition is coated on the surface of the formed B-staged product layer opposite the circuit board side.

[0193] 3(c) and 3(d) are diagrams showing the second coating step and the second photocuring step, respectively. As shown in FIG. 3(c), an inkjet device (inkjet system) is used to apply a curable composition to the surface of the B-staged product layer 3B opposite the circuit board 1 side, thereby forming a curable composition layer 3A on the surface of the B-staged product layer 3B. Next, as shown in FIG. 3(d), light is irradiated onto the applied curable composition layer 3A from a light irradiation unit 52 of the inkjet device, thereby forming a B-staged product layer 3B.

[0194] 2(a) and 2(b) and 3(c) and 3(d), the coating step and the photocuring step are performed twice in the thickness direction of the curable composition layer, as shown in FIGS. 2(a) and 2(b) and 3(c) and 3(d). By performing the coating step and the photocuring step multiple times in the thickness direction of the curable composition layer, the thickness of the B-staged product layer can be increased, and the ratio (height (thickness) / width) (aspect ratio) of the B-staged product layer can be increased. The coating step and the photocuring step may each be performed two or more times, or three or more times.

[0195] In the coating step and the photo-curing step, the coating and photo-curing are repeated to form a B-stage compound layer 3B in contact with the side surface of the electronic component 2, as shown in Fig. 4(e). In Fig. 4(e), the B-stage compound layer 3B in contact with the side surface and top surface of the electronic component 2 is formed.

[0196] Next, the B-staged product layer 3B is thermally cured by heating (thermal curing step). The laminated structure including the circuit board 1, electronic component 2, and B-staged product layer 3B obtained in FIG. 4(e) is heated to thermally cure the B-staged product layer 3B. This forms the adhesive portion 3 as shown in FIG. 4(f). The adhesive portion 3 is a photo- and thermo-cured product layer of the curable composition.

[0197] 4(g), the upper surface and side surfaces of the adhesive portion 3 are sealed with resin. By disposing the resin on the upper surface and side surfaces of the adhesive portion 3, a molded resin portion 44 is formed.

[0198] In this manner, the electronic component 10 shown in FIG. 1 can be obtained.

[0199] In the electronic component, the adhesive portion may be in contact with the side surface of the electronic member over the entire periphery of the electronic member, or may be in contact with the side surface of only a portion of the periphery of the electronic member.

[0200] From the viewpoint of further enhancing the sealing property of the air cavity, it is preferable that the adhesive portion of the electronic component contacts the entire side surface of the electronic component from the upper end to the lower end. From the viewpoint of more effectively exhibiting the effects of the present invention, it is preferable that the adhesive portion of the electronic component contacts the entire side surface of the electronic component in the up-down direction. From the viewpoint of more effectively exhibiting the effects of the present invention, in the method for producing an electronic component, it is preferable that the curable composition layer is formed in the step (2) of forming a curable composition layer (coating step) so as to contact the entire side surface of the electronic component in the up-down direction. From the viewpoint of more effectively exhibiting the effects of the present invention, it is preferable that the curable composition layer is formed in the step (2) of forming a curable composition layer (coating step) so as to contact the entire side surface of the electronic component in the up-down direction. From the viewpoint of further enhancing the sealing property of the air cavity, it is preferable that the curable composition is applied in the step (2) of forming a curable composition layer (coating step) so as to contact the entire side surface of the electronic component from the upper end to the lower end. In this specification, "from the top to the bottom of the side surface of the electronic component" means from the top to the bottom of the side surface of the electronic component excluding the solder balls.

[0201] In the electronic component, the adhesive portion may be in contact with a portion of the side surface of the electronic member, or may be in contact with the entire side surface of the electronic member. From the viewpoint of more effectively exerting the effects of the present invention, it is preferable that the adhesive portion be in contact with the entire side surface of the electronic member in the electronic component. From the viewpoint of further improving the air cavity sealing, it is preferable that in the method for producing an electronic component, in the step (2) of forming a curable composition layer (coating step), the curable composition layer is formed so as to be in contact with the entire side surface of the electronic member. From the viewpoint of further improving the air cavity sealing, it is preferable that in the method for producing an electronic component, in the step (2) of forming a curable composition layer (coating step), the curable composition is coated on the entire side surface of the electronic member.

[0202] From the viewpoint of further effectively achieving the effects of the present invention, in the electronic component, it is preferable that the adhesive portion contacts the edge portion of the upper surface of the electronic component, and it is more preferable that the adhesive portion contacts the entire upper surface of the electronic component. From the viewpoint of further improving the sealing property of the air cavity, in the manufacturing method of the electronic component, it is preferable that the curable composition layer is formed so as to contact the edge portion of the upper surface of the electronic component in the step (2) of forming the curable composition layer (coating step). From the viewpoint of further improving the sealing property of the air cavity, in the manufacturing method of the electronic component, it is preferable that the curable composition is applied to the edge portion of the upper surface of the electronic component in the step (2) of forming the curable composition layer (coating step), and it is more preferable that the curable composition is applied to the entire upper surface of the electronic component. Note that the edge portion of the upper surface of the electronic component is the portion (edge ​​portion) located on the upper surface of the electronic component, and is different from the portion located on the side surface of the electronic component.

[0203] The adhesive portion may contact an area of ​​5 μm extending inward from the edge of the upper surface of the electronic component, or an area of ​​1000 μm extending inward from the edge of the upper surface of the electronic component. Preferably, the edge of the upper surface of the electronic component is an area of ​​5 μm to 1000 μm extending inward from the edge of the upper surface of the electronic component.

[0204] From the viewpoint of more effectively exerting the effects of the present invention, it is preferable that in the electronic component, the adhesive portion does not contact the lower surface of the electronic member. From the viewpoint of further improving the sealing property of the air cavity, it is preferable that in the manufacturing method of the electronic component, in the step (2) of forming a curable composition layer (coating step), the curable composition layer is formed so as not to contact the lower surface of the electronic member. From the viewpoint of further improving the sealing property of the air cavity, it is preferable that in the manufacturing method of the electronic component, in the step (2) of forming a curable composition layer (coating step), the curable composition is not coated on the lower surface of the electronic member.

[0205] From the viewpoint of further improving the air cavity sealing property, in the above-mentioned method for producing an electronic component, it is preferable to photo-cure the curable composition in the step (3) of forming an adhesive part (curing step), and it is more preferable to photo-cure and heat-cure the curable composition. From the viewpoint of further improving the air cavity sealing property, it is preferable that in the above-mentioned method for producing an electronic component, it is preferable to curing the curable composition by light irradiation and heat in the above-mentioned step (3) of forming an adhesive part (curing step). From the viewpoint of further improving the air cavity sealing property, it is preferable that in the above-mentioned method for producing an electronic component, it is preferable that in the above-mentioned step (3) of forming an adhesive part (curing step), it includes a step (photo-curing step) of photo-curing the curable composition layer to form the adhesive part. When the curable composition layer is photo-cured to form the adhesive part, heat-curing may be performed after photo-curing.

[0206] In the method for producing an electronic component, the step (3) of forming an adhesive joint (curing step) preferably includes a step of photocuring the curable composition layer to obtain a B-staged product layer (photocuring step), and a step of thermally curing the B-staged product layer to obtain a cured product (adhesive joint) of the curable composition layer (thermal curing step). In this case, the sealing of the air cavity can be further improved.

[0207] In the method for producing an electronic component, the step (3) of forming an adhesive joint (curing step) preferably includes a step (photocuring step) of photocuring the curable composition layer to obtain a multilayer B-staged product layer each time one or more drops of the curable composition are applied, and a step (thermal curing step) of thermally curing the multilayer B-staged product layer to form a multilayer adhesive joint. In this case, the adhesive joint can be formed with high precision, and the effects of the present invention can be effectively achieved.

[0208] The step of obtaining multiple B-staged product layers (photocuring step) is carried out by repeatedly applying one or more drops of the curable composition and photocuring the curable composition layer. The application and photocuring are repeated in the thickness direction of the curable composition layer (thickness direction of the resulting multiple B-staged product layers) to form multiple B-staged product layers. Specifically, the step of obtaining multiple B-staged product layers (photocuring step) is as follows: A step of applying one or more drops of the curable composition and photocuring the first curable composition layer to obtain a first B-staged product layer (lower B-staged product layer) is carried out. Next, a step of applying one or more drops of the curable composition on the first B-staged product layer (lower B-staged product layer) and photocuring the second curable composition layer (upper B-staged product layer) is carried out to obtain a second B-staged product layer. By repeating this operation n times (n is an integer of 2 or greater), n B-staged material layers (n in total) are obtained. The final nth operation is a step of applying multiple drops or one drop of the curable composition onto the (n-1)th B-staged material layer and photocuring the nth curable composition layer to obtain the nth B-staged material layer. After the photocuring step of obtaining multiple B-staged material layers, a step of forming a multilayer adhesive joint (thermal curing step) is performed. The step of forming a multilayer adhesive joint (thermal curing step) is a step of thermally curing n B-staged material layers to form n adhesive joints.

[0209] In the photo-curing step, ultraviolet light is preferably irradiated. The irradiance and irradiation time of the ultraviolet light in the photo-curing step can be appropriately changed depending on the composition of the curable composition and the coating thickness of the curable composition. The irradiance of the ultraviolet light in the photo-curing step is, for example, 1000 mW / cm 2 It may be 5000mW / cm or more. 2 It may be 10,000 mW / cm or more. 2 may be less than 8000 mW / cm 2 The irradiation time of ultraviolet light 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.

[0210] The heating temperature and heating time in the thermal curing step can be appropriately changed depending on the composition of the curable composition and the thickness of the B-staged product layer. The heating temperature in the thermal curing step may be, for example, 100°C or higher, 120°C or higher, and 250°C or lower, or 200°C or lower. The heating time in the thermal curing step may be, for example, 5 minutes or higher, 30 minutes or higher, or 600 minutes or lower, or 300 minutes or lower.

[0211] The electronic component may or may not have a molded resin portion. In the method for manufacturing an electronic component, the upper surface and side surface of the adhesive portion may or may not be sealed with resin. From the viewpoint of further improving the sealing performance of the air cavity, it is preferable that the method for manufacturing an electronic component further includes (4) a step of sealing the upper surface and side surface of the adhesive portion with resin (resin sealing step). From the viewpoint of further improving the sealing performance of the air cavity, it is preferable that the method for manufacturing an electronic component further includes (4) a step of sealing with resin (resin sealing step) of disposing resin on the upper surface and side surface of the adhesive portion to form a molded resin portion.

[0212] Examples of the resin include epoxy resin, acrylic resin, phenol resin, silicone resin, fluororesin, etc. From the viewpoint of further improving the sealing property of the air cavity, the resin is preferably epoxy resin, acrylic resin, or phenol resin, and more preferably epoxy resin or acrylic resin.

[0213] The ratio of the height of the adhesive portion to the width of the adhesive portion (height / width) is preferably 1.0 or more, more preferably 1.5 or more, even more preferably 2.0 or more, and particularly preferably 2.5 or more. When the ratio (height / width) is equal to or greater than the lower limit, the adhesiveness and sealing properties can be further improved. The upper limit of the ratio (height / width) is not particularly limited. The ratio (height / width) of the adhesive portion may be 100 or less, 50 or less, 10 or less, or 5.0 or less. From the viewpoint of miniaturizing the resulting electronic component, the ratio (height / width) is preferably 5.0 or less.

[0214] The width, height, shape, etc. of the adhesive portion can be changed as appropriate.

[0215] The width of the adhesive portion is preferably the width of the adhesive portion at the contact surface between the surface of the circuit board and the adhesive portion, and at the contact surface between the surface of the circuit board and the adhesive portion, the width of the adhesive portion may be 50 μm or more, 100 μm or more, 150 μm or more, or 250 μm or less, 230 μm or less, or 200 μm or less.

[0216] The height of the adhesive portion is preferably the distance from the contact surface between the surface of the circuit board and the adhesive portion to the maximum height position of the adhesive portion, and may be 100 μm or more, 200 μm or more, 300 μm or more, 500 μm or less, 450 μm or less, or 400 μm or less.

[0217] The circuit board is a substrate having a circuit pattern on its surface.

[0218] Examples of the electronic components include semiconductor chips, capacitors, and light-emitting elements.

[0219] Examples of the semiconductor chip include a surface acoustic wave filter, a bulk acoustic wave filter, and a film acoustic resonator filter.

[0220] Examples of the light-emitting element include a light-emitting diode and a semiconductor laser.

[0221] The electronic component is preferably a semiconductor chip, a capacitor, or a light-emitting element, more preferably a semiconductor chip, and further preferably a surface acoustic wave filter, a bulk acoustic wave filter, or a film acoustic resonator filter.

[0222] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0223] The following materials were prepared:

[0224] (A1) First photocurable compound: Dipentaerythritol hexaacrylate (hexafunctional (meth)acrylate compound, "DPHA" manufactured by Daicel-Allnex Corporation) Ethoxylated dipentaerythritol hexaacrylate (hexafunctional (meth)acrylate compound, "A-DPH-12E" manufactured by Shin-Nakamura Chemical Co., Ltd.) Trimethylolpropane triacrylate (trifunctional (meth)acrylate compound, "TMPTA" manufactured by Daicel-Allnex Corporation)

[0225] (A2) Second photocurable compound: Methyl-2-(allyloxymethyl)acrylic acid ("AOMA" manufactured by Nippon Shokubai Co., Ltd., a monofunctional cyclopolymerizable compound) Tricyclodecane dimethanol diacrylate (bifunctional (meth)acrylate compound, Daicel-Allnex "IRR-214K") Bisphenol AEO 3.8 mole adduct diacrylate (bifunctional (meth)acrylate compound, "#700HV" manufactured by Osaka Organic Chemical Industry Co., Ltd.) Isobornyl acrylate (monofunctional (meth)acrylate compound, "IBOA" manufactured by Nippon Shokubai Co., Ltd.)

[0226] (B) Photopolymerization initiator: 2-(Dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholinyl)phenyl]-1-butanone (IGM "Omnirad379")

[0227] (C) Rubber particles: Silicone rubber particles (core-shell particles with a silicone rubber core and a polymethyl methacrylate (PMMA) shell, Kaneka Corporation "MX-962," glass transition temperature -100°C) Polybutadiene rubber particles (core-shell particles with a polybutadiene rubber core and a polymethyl methacrylate (PMMA) shell, Kaneka Corporation "MX-267", glass transition temperature -80°C) Acrylic rubber particles (core-shell particles with an acrylic rubber core and a polymethyl methacrylate (PMMA) shell, Nippon Shokubai Co., Ltd. "BPF-307", glass transition temperature -30°C)

[0228] (D) Thermosetting compound: Bisphenol F liquid epoxy compound (DIC "EPICLON EXA-830CRP")

[0229] (E) Heat curing agent: 1,3-bis(3-aminophenoxy)benzene ("APB-N" manufactured by Mitsui Chemicals, Inc.)

[0230] (Examples 1 to 23 and Comparative Examples 1 and 2) The components shown in Tables 1 to 5 were blended in the amounts (% by weight) shown in Tables 1 to 5 and mixed uniformly to obtain curable compositions for inkjet use and for forming air cavities (curable compositions).

[0231] (evaluation) (1) Ability to form a hardened layer with a large aspect ratio A semiconductor wafer (thickness: 0.7 mm) was prepared. The obtained curable composition was applied onto the surface of this semiconductor wafer using an inkjet device to form a curable composition layer (application step). Next, the curable composition layer was irradiated with light to promote curing of the curable composition layer and form a B-staged product (B-staged product layer) (photocuring step). Note that the light irradiation in the photocuring step was performed using a UV-LED lamp with a main wavelength of 365 nm at 2000 mW / cm. 2 ×0.1 seconds (accumulated light intensity 200 mJ / cm 2 ) conditions. In the coating step and the photocuring step, coating and photocuring were repeated in the thickness direction of the curable composition layer to form a B-staged product layer. The obtained B-staged product layer was observed at 20x magnification using a laser microscope (Olympus Corporation, "OLS4000"), and the ratio (height / width) (aspect ratio) was determined. The formability of a cured product layer with a large aspect ratio was evaluated according to the following criteria. The width of the formed B-staged product layer was 100 μm. Therefore, for example, a B-staged product layer with an aspect ratio of 2.5 means a B-staged product layer with a height of 250 μm and a width of 100 μm.

[0232] [Criteria for determining the formability of hardened layers with large aspect ratios] XX: Able to form B-stage compound layers with an aspect ratio of 2.5 or more XX: A B-stage compound layer with an aspect ratio of 2.0 or more and less than 2.5 can be formed ○: A B-stage compound layer with an aspect ratio of 1.0 or more and less than 2.0 can be formed ×: A B-stage compound layer with an aspect ratio of less than 1.0 can be formed

[0233] (2) Thermal cycle characteristics (crack suppression) Laminate formation: A semiconductor wafer (thickness: 0.7 mm) was prepared. The resulting curable composition was applied to the entire surface of the semiconductor wafer while circulating at 55°C, and a first photo-curing step (UV-LED lamp with a main wavelength of 365 nm, 5000 mW / cm 2A curable composition layer was formed by applying a 0.1-second exposure 0.2 seconds after application. A semiconductor chip (3 × 3 mm, 0.7 mm thick) was then mounted on the curable composition layer. The application and curing steps were repeated four times to cover the semiconductor chip, forming a B-staged product layer. The resulting B-staged product layer was then thermally cured using an exhaust oven at 130°C for 1 hour and 170°C for 2 hours, yielding a laminate (a laminate for evaluating thermal cycle characteristics) in which partition walls were formed around the periphery of the semiconductor chip mounted on the semiconductor wafer.

[0234] Thermal shock resistance test: The resulting laminate was cooled to -55°C for 15 minutes, heated to 125°C at a heating rate of 100°C / min, heated at 125°C for 15 minutes, and cooled to -55°C at a cooling rate of 100°C / min. This cooling-heating cycle was repeated 1000 times. After 250 cycles, 500 cycles, and 1000 cycles, the laminate was observed using a microscope (Keyence Corporation, "VHX-5000") to determine whether cracks had occurred in the partition walls. The crack suppression was evaluated according to the following criteria.

[0235] [Crack suppression criteria] ○○○: No cracks after 1000 cycles ○〇: No cracks after 500 cycles, and cracks after 1000 cycles ○: No cracks after 250 cycles and cracks after 500 cycles ×: Cracks found after 250 cycles

[0236] The compositions and results are shown in Tables 1 to 5 below.

[0237] [Table 1]

[0238] [Table 2]

[0239] [Table 3]

[0240] [Table 4]

[0241] [Table 5] [Explanation of symbols]

[0242] 1...Circuit board 2...Electronic materials 3...Adhesive part 3A…Curable composition layer 3B...B-stage compound layer 10...Electronic components 41...Solder ball 42...Resin sheet 43...Connection terminal 44...Molded resin part 51...Discharge part 52...Light irradiation unit R...Air cavity

Claims

1. A photocurable composition comprising a photopolymerization initiator and rubber particles, the photocurable compound includes a first photocurable compound having three or more (meth)acryloyl groups, The curable composition for inkjet printing and air cavity formation, wherein the rubber particles are core-shell particles having a core and a shell disposed on the surface of the core.

2. 2. The curable composition for inkjet printing and for forming an air cavity according to claim 1, wherein a content of the first photocurable compound is 1% by weight or more and 10% by weight or less, based on 100% by weight of the curable composition for inkjet printing and for forming an air cavity.

3. The curable composition for inkjet printing and for forming an air cavity according to claim 1 or 2, wherein the first photocurable compound includes a photocurable compound having six or more (meth)acryloyl groups.

4. The curable composition for inkjet printing and air cavity formation according to claim 1 or 2, wherein the first photocurable compound comprises dipentaerythritol hexa(meth)acrylate.

5. 3. The curable composition for inkjet printing and for forming an air cavity according to claim 1, wherein the content of the rubber particles is 5% by weight or more and 10% by weight or less, based on 100% by weight of the curable composition for inkjet printing and for forming an air cavity.

6. The curable composition for inkjet printing and air cavity formation according to claim 1 or 2, wherein the rubber particles comprise silicone rubber or polybutadiene rubber.

7. the photocurable compound includes a second photocurable compound different from the first photocurable compound; 3. The curable composition for inkjet printing and for forming an air cavity according to claim 1, wherein the second photocurable compound comprises a photocurable compound having two or less (meth)acryloyl groups or a cyclopolymerizable compound.

8. the second photocurable compound includes a cyclopolymerizable compound, 8. The curable composition for inkjet printing and for forming an air cavity according to claim 7, wherein a content of the cyclopolymerizable compound is 20% by weight or more and 50% by weight or less, based on 100% by weight of the curable composition for inkjet printing and for forming an air cavity.

9. The curable composition for inkjet printing and for forming an air cavity according to claim 1 or 2, further comprising a thermosetting compound and a thermosetting agent.

10. The device includes a circuit board, an electronic component, and an adhesive portion. the electronic component is mounted on the circuit board, The adhesive portion is a cured product of the curable composition for inkjet printing and for forming an air cavity according to claim 1 or 2, the adhesive portion is in contact with the upper surface of the circuit board and at least a part of the side surface of the electronic component, an air cavity is formed by the circuit board, the electronic member, and the adhesive portion;

11. Using a circuit board with electronic components mounted on the top surface, a step of applying the curable composition for inkjet printing and for forming air cavities according to claim 1 or 2 onto an upper surface of the circuit board by an inkjet method to form a curable composition layer; and curing the curable composition layer to form an adhesive portion, In the step of forming the curable composition layer, the curable composition layer is formed so as to be in contact with at least a part of a side surface of the electronic member; and forming an air cavity by the circuit board, the electronic member, and the adhesive portion.

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