Photocurable resin composition and method for curing the same, and mounting substrate and method for manufacturing three-dimensional molding

Abstract

To provide a photocurable resin composition which is curable by light irradiation and gives a cured product having sufficient mechanical characteristics, and a method for curing the same.SOLUTION: A method for curing a photocurable resin composition includes (i) a heating step of heating a photocurable resin composition, (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device, and coating the discharged photocurable resin composition to an adherend, and (iii) a light irradiation step of irradiating the photocurable resin composition which has been heated and discharged from the nozzle with light, wherein the photocurable resin composition contains a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound is radical polymerizable or cationic polymerizable, and the photopolymerization initiator is activated by light irradiation.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a photocurable resin composition and a method for curing the same, as well as a method for producing a mounting substrate and a three-dimensional object. [Background technology]

[0002] Patent Document 1 proposes a method for coating a semiconductor element with resin, which comprises dripping a photocurable resin onto a semiconductor element, and then irradiating the photocurable resin with light to harden it and coat the semiconductor element with the resin.

[0003] Patent Document 2 proposes "a method for producing a three-dimensional object, comprising the steps of irradiating a cationic ultraviolet-curable composition with ultraviolet light and injecting the cationic ultraviolet-curable composition irradiated with ultraviolet light into a mold."

[0004] Patent Document 3 proposes "a method of forming a pin holding portion on a lead frame, in which a resin material 4 is applied from an upper dispenser to the surface of predetermined locations of each pin 5 and to the spaces between each pin 6 on a lead frame 2 placed on a table 1, and then cured to form a resin pin holding portion 7, characterized in that an ultraviolet-curable resin material 4 which is elastic and non-conductive, has low impurities and small thermal expansion, is precisely discharged per unit time from a needle portion 8 at the lower end of the dispenser and applied to the lead frame 1, and ultraviolet light 3 is irradiated onto the applied resin material 4 from an ultraviolet irradiation light 9 which is provided integrally with the needle portion 8 and facing downward, so that the resin material 4 is applied to the lead frame 2 while simultaneously undergoing a curing process." [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Publication No. 5-175261 [Patent Document 2] JP 2001-96630 A [Patent Document 3] Japanese Patent Application Publication No. 6-196620 Summary of the Invention [Problem to be solved by the invention]

[0006] Conventionally, for example, as a resin composition that is applied to electronic components mounted on a substrate in order to protect the electronic components on the substrate and then cured, a thermosetting resin composition containing a considerable amount of inorganic filler has generally been used.

[0007] However, a problem with thermosetting resin compositions is that they consume a large amount of energy for heating, and therefore, in recent years, from the viewpoint of carbon neutrality, attempts have been made to apply environmentally friendly photocurable resin compositions, instead of thermosetting resin compositions, to various applications.

[0008] The photocurable resin composition itself must have sufficient light transmittance in order to irradiate a sufficient amount of light to the photopolymerization initiator contained therein.

[0009] On the other hand, in order to impart sufficient mechanical properties to the cured product of the photocurable resin composition and to control the linear expansion coefficient of the cured product to suppress peeling from the adherend, it is desirable to include a significant amount of inorganic filler in the photocurable resin composition. However, a photocurable resin composition containing a significant amount of inorganic filler has low light transmittance. Therefore, when it is desired to form a reinforcement structure with a high aspect ratio, which is thick or long in the height direction and short in the width direction, the photocurable resin composition cannot be cured sufficiently to the bottom. [Means for solving the problem]

[0010] One aspect of the present invention relates to a photocurable resin composition that is discharged in a heated state from a nozzle of an application device and applied to an adherend while being irradiated with light, the photocurable resin composition comprising a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerizability or cationic polymerizability, the photopolymerization initiator being activated by light irradiation, and the content of the inorganic filler being 75 mass% or more.

[0011] Another aspect of the present invention relates to a method for curing a photocurable resin composition, the method including: (i) a heating step of heating a photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device and coating the composition on an adherend; and (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light, the photocurable resin composition including a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerizability or cation polymerizability, and the photopolymerization initiator being activated by light irradiation.

[0012] Yet another aspect of the present invention relates to a method for manufacturing a mounting substrate, the method comprising: (i) a heating step of heating a photocurable resin composition to reduce viscosity; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device and coating the composition on an adherend; and (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light, the adherend including a substrate and an electronic component mounted on the substrate, the photocurable resin composition including a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerization or cation polymerization properties, the photopolymerization initiator being activated by light irradiation, and the substrate and the electronic component being bonded together by a cured product of the photocurable resin composition.

[0013] Yet another aspect of the present invention relates to a method for producing a three-dimensional object, comprising: (i) a heating step of heating a photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device and coating the composition on an adherend; and (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light, wherein the photocurable resin composition contains a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound has radical polymerization or cationic polymerization properties, the photopolymerization initiator is activated by light irradiation, and the photocurable resin composition is applied to the adherend and cured, and the heating step, the coating step, and the light irradiation step are repeated with the photocurable resin composition being used as a new adherend. Effect of the Invention

[0014] According to the present invention, it is possible to provide a photocurable resin composition that can be cured by irradiation with light to give a cured product having sufficient mechanical properties, and a method for curing the same. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] In the following, the embodiment of the present disclosure will be described with examples, but the present disclosure is not limited to the examples described below. In the following description, specific numerical values ​​and materials may be exemplified, but other numerical values ​​and materials may be applied as long as the effects of the present disclosure are obtained. In this specification, the description "numerical value A to numerical value B" includes numerical value A and numerical value B, and can be read as "numerical value A or more and numerical value B or less." In the following description, when a lower limit and an upper limit of a numerical value related to a specific physical property or condition are exemplified, any of the exemplified lower limits and any of the exemplified upper limits can be arbitrarily combined as long as the lower limit is not equal to or greater than the upper limit.

[0016] The present disclosure relates to the following: [Technology 1] A reactive compound, a photopolymerization initiator, and an inorganic filler are included, The reactive compound has radical polymerizability or cationic polymerizability, The photopolymerization initiator is activated by light irradiation, The photocurable resin composition has an inorganic filler content of 75 mass % or more. [Technology 2] The photocurable resin composition according to claim 1, which is discharged from a nozzle of a coating device in a heated state and applied to an adherend while being irradiated with light. [Technology 3] The photocurable resin composition according to claim 1 or 2, wherein the reactive compound is at least one selected from the group consisting of an epoxy resin, an oxetane compound, or an acrylic monomer. [Technology 4] The photocurable resin composition according to any one of Techniques 1 to 3, wherein the inorganic filler is silica particles. [Technology 5] 5. The photocurable resin composition according to any one of Techniques 1 to 4, wherein the content of the inorganic filler or silica particles is 80 mass % or more. [Technology 6] 6. The photocurable resin composition according to any one of claims 1 to 5, which produces a cured product having a linear expansion coefficient of 25 ppm / K or less by the light irradiation.

[0017] [Technology 7] (i) a heating step of heating the photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device to coat an adherend; (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light; Equipped with The photocurable resin composition includes a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerizability or cationic polymerizability, and the photopolymerization initiator is activated by light irradiation. [Technology 8] 8. The method for curing a photocurable resin composition according to claim 7, wherein the content of the inorganic filler in the photocurable resin composition is 40 mass % or more. [Technology 9] 9. The method for curing a photocurable resin composition according to claim 7 or 8, wherein the heating step is a step of heating the photocurable resin composition to 50° C. or higher and 100° C. or lower. [Technology 10] 10. The method for curing a photocurable resin composition according to any one of Techniques 7 to 9, wherein in the heating step, the photocurable resin composition is heated in a liquid reservoir included in the coating device. [Technology 11] The application device is a jet dispenser, The method for curing a photocurable resin composition according to any one of Techniques 7 to 10, wherein the photocurable resin composition is discharged onto the adherend in the form of spots or lines. [Technology 12] 12. The method for curing a photocurable resin composition according to any one of claims 7 to 11, wherein in the light irradiation step, the coating film of the photocurable resin composition is irradiated with light within 30 seconds after the photocurable resin composition is discharged from the nozzle. [Technology 13] 13. The method for curing a photocurable resin composition according to any one of Techniques 7 to 12, wherein the thickness of one coating film of the photocurable resin composition applied to the adherend is 2 mm or less. [Technology 14] The photocurable resin composition applied to the adherend and cured is used as a new adherend, and the heating step, the application step, and the light irradiation step are repeated. [Technology 15] (i) a heating step of heating the photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device to coat an adherend; (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light; Equipped with The adherend includes a substrate and an electronic component mounted on the substrate, The photocurable resin composition includes a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerizability or cationic polymerizability, the photopolymerization initiator being activated by light irradiation, the substrate and the electronic component are bonded to each other by a cured product of the photocurable resin composition. [Technology 16] (i) a heating step of heating the photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device to coat an adherend; (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light; Equipped with The photocurable resin composition includes a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerizability or cationic polymerizability, the photopolymerization initiator being activated by light irradiation, the photocurable resin composition applied to the adherend and cured is used as a new adherend, and the heating step, the application step, and the light irradiation step are repeated in this method for manufacturing a three-dimensional object.

[0018] (Photocurable resin composition) The photocurable resin composition according to the present disclosure (hereinafter also referred to as "resin composition (A)") contains a reactive compound, a photopolymerization initiator, and an inorganic filler.

[0019] The reactive compound may have polymerizability, for example, radical polymerizability or cationic polymerizability. The reactive compound may be at least one selected from the group consisting of epoxy resins and acrylic monomers. The type of epoxy resin is not particularly limited as long as it has radical polymerizability or cationic polymerizability. The type of acrylic monomer is also not particularly limited as long as it has radical polymerizability or cationic polymerizability. The acrylic monomer may be an acrylic oligomer as long as it has polymerizability.

[0020] Epoxy resins that can be used as reactive compounds are not particularly limited, but for example, bisphenol type epoxy, phenol novolac type epoxy, alicyclic epoxy resin, glycidyl ester type epoxy of organic carboxylic acid, etc. can be used. Bisphenol type epoxy includes bisphenol A type epoxy, bisphenol F type epoxy, bisphenol AD ​​type epoxy, hydrogenated bisphenol A type epoxy, etc. Bisphenol type epoxy includes C type epoxy of bisphenols such as bisphenol A, bisphenol F, bisphenol AD, etc. 2-3 Also included are diglycidyl ethers of alkylene oxide adducts. The epoxy resins may be used alone or in combination of two or more.

[0021] The acrylic monomer that can be used as the reactive compound is not particularly limited, but may be, for example, (meth)acrylic acid ester, di(meth)acrylic acid ester of alkylene glycol, etc. The acrylic acid ester and the methacrylic acid ester are collectively called (meth)acrylic acid ester. The acrylic monomer may be used alone or in combination of two or more kinds.

[0022] An oxetane compound may be used as the reactive compound. The oxetane compound that can be used as the reactive compound is not particularly limited, but includes 3-hydroxymethyl-3-methyloxetane, 3-hydroxymethyl-3-ethyloxetane, 3-hydroxymethyl-3-propyloxetane, 3-hydroxymethyl-3-n-butyloxetane, 3-hydroxymethyl-3-phenyloxetane, 3-hydroxymethyl-3-benzyloxetane, 3-hydroxyethyl-3-methyloxetane, 3-hydroxyethyl-3-ethyloxetane, 3-hydroxyethyl-3-propyloxetane, 3 1,4 bis{[(3-ethyl-3-oxetanyl)methoxy]methyl}benzene, 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane, and di[1-ethyl(3-oxetanyl)]methyl ether can be used.

[0023] The photopolymerization initiator may be a compound that is activated by light irradiation to promote polymerization of the reactive compound, for example, a compound that is activated by UV light irradiation. When the reactive compound has radical polymerizability, the photopolymerization initiator may be a radical polymerization initiator that generates radicals by light irradiation. When the reactive compound has cationic polymerizability, the photopolymerization initiator may be a cationic polymerization initiator that generates cations by light irradiation. The photopolymerization initiator may be used alone or in combination of two or more kinds.

[0024] Examples of the radical polymerization initiator include an alkylphenone initiator and an acylphosphine oxide initiator. Examples of the cationic polymerization initiator include a sulfonium salt initiator and an iodonium salt initiator. However, the type of the photopolymerization initiator is not particularly limited.

[0025] The resin composition (A) can be used, for example, in applications in which it is discharged from the nozzle of an application device in a heated state, and then irradiated with light such as UV light after being applied to an adherend. By discharging from the nozzle in a heated state, thermal energy can be imparted to the reactive compound and the photopolymerization initiator in advance, and the polymerization reaction proceeds rapidly due to the thermal energy, starting from the photopolymerization initiator activated by UV light.

[0026] For the above reasons, the resin composition (A) in a heated state can be sufficiently cured by irradiation with a smaller amount of light than the resin composition (A) in a non-heated state. Therefore, the resin composition (A) may contain a large amount of inorganic filler. In general, the content of inorganic filler in a photocurable resin composition is considered to be limited to about 30 mass% at most in order to provide the photocurable resin composition itself with sufficient light transmittance. On the other hand, the content of inorganic filler in the resin composition (A) may be, for example, 40 mass% or more. The content of inorganic filler may be less than 40 mass%, but in terms of controlling the strength and linear expansion coefficient of the cured product, it is often desirable to use 40 mass% or more, and even 50 mass% or more or 60 mass% or more.

[0027] When the inorganic filler contains silica particles, the content of the silica particles in the resin composition (A) may be 75% by mass or more, or 80% by mass or more. The type of silica particles is not particularly limited, but spherical silica particles are preferred.

[0028] The linear expansion coefficient of a cured product of the resin composition (A) containing the inorganic filler in the above content is, for example, 25 ppm / K or less, and can be as low as 20 ppm / K or less.

[0029] The inorganic filler is not limited to silica particles. For example, various inorganic fillers such as alumina, boron nitride, talc, etc. can be used. The content of the inorganic filler is determined according to the type of inorganic filler.

[0030] (Method of curing photocurable resin composition) The method for curing a photocurable resin composition (resin composition (A)) according to the present disclosure (hereinafter also referred to as “curing method (A)”) includes a heating step (i), an application step (ii), and a light irradiation step (iii).

[0031] The heating step (i) is a step of heating the resin composition (A). The heating step (i) is a step of previously imparting a part of the energy required for the polymerization reaction to the resin composition (A), and is also a step of reducing the viscosity of the resin composition (A).

[0032] The temperature at which the resin composition (A) is heated may be any temperature that does not deteriorate the resin composition (A) and can sufficiently reduce the viscosity of the resin composition (A). The heating step (i) is preferably a step of heating the resin composition (A) to, for example, 50°C or more and 100°C or less.

[0033] The timing of heating is not limited, but is preferably immediately before discharge. A method of heating the nozzle or dispensing nozzle of the coating device by a heating device is common, but the entire resin composition (A) contained in the syringe may be heated as necessary. The resin composition (A) may be heated simultaneously with or after discharge, and the entire substrate may be heated by a stage heater or a hot air spot heater with local temperature control may be used.

[0034] The coating step (ii) is a step of discharging the heated resin composition (A) from a nozzle of a coating device and coating the adherend. The coating device and the adherend are not particularly limited.

[0035] The coating device may be, for example, a needle dispenser or a jet dispenser. Among them, a jet dispenser is preferable in that the resin composition (A) can be coated on the adherend without contacting the adherend, and therefore the coating tact time is short and efficient coating can be performed. According to the jet dispenser, the resin composition (A) is discharged onto the adherend in the form of spots or lines. A line-shaped coating film is formed by successively coating spots.

[0036] The light irradiation step (iii) is a step of irradiating the resin composition (A) that has been heated and discharged from the nozzle with light such as UV light. The light irradiation step (iii) is a step of activating the photopolymerization initiator to generate radicals or cations.

[0037] The timing of light irradiation of the resin composition (A) is not particularly limited. However, from the viewpoint of utilizing the state in which the heated resin retains thermal energy, it is preferable to irradiate the resin composition (A) with light within 30 seconds (preferably within 5 seconds) after it is discharged from the nozzle. The light irradiation may be performed by a light irradiation device integrated with the nozzle. The light irradiation device may be attached to a moving head that operates the nozzle, and may be configured to move together with the movement of the nozzle. The moving head may be configured to be movable in the horizontal XY direction (two-dimensional direction) or the XYZ direction (three-dimensional direction).

[0038] The thickness of one layer of the photocurable resin composition applied to the adherend is preferably, for example, 2 mm or less. In this case, the curing is likely to proceed sufficiently by the energy of the heat and light irradiation applied in advance. The thickness of one layer of the photocurable resin composition may be 1 mm or less, or 0.8 mm or less.

[0039] The resin composition (A) applied to the adherend and cured may be used as a new adherend, and the heating step (i), the coating step (ii), and the light irradiation step (iii) may be repeated. Even if the thickness of a single coating film is 2 mm or less, a coating film of any thickness or a three-dimensional resin molded body can be formed by stacking multiple coating films. The heating step (i) does not need to be repeated as an intermittent process, and may be a continuous process. That is, during the period in which the coating step (ii) and the light irradiation step (iii) are repeated, the heating step (i) may be continuously performed on a predetermined amount of the resin composition (A) that is provided to the coating step (ii) within a predetermined period.

[0040] An example of the adherend may include a substrate and an electronic component mounted on the substrate. For example, the resin composition (A) may be used as an adhesive to more firmly fix the electronic component mounted on the substrate. In this case, the "curing method of the photocurable resin composition" can be rephrased as "a manufacturing method of a mounting substrate".

[0041] That is, in another aspect, the method for curing a photocurable resin composition may be a method for manufacturing a mounting substrate, comprising: (i) a heating step of heating the photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device and coating the composition on an adherend; and (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light, wherein the adherend includes a substrate and an electronic component mounted on the substrate; the photocurable resin composition includes a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound has radical polymerization or cation polymerization properties, the photopolymerization initiator is activated by light irradiation, and the substrate and the electronic component are bonded to each other by the cured product of the photocurable resin composition.

[0042] In addition, when the resin composition (A) applied to the adherend and cured is used as a new adherend and the heating step (i), the coating step (ii) and the light irradiation step (iii) are repeated, the "curing method of the photocurable resin composition" can be rephrased as "a method for producing a three-dimensional object". When the resin composition (A) having a high content of inorganic filler can be cured by light irradiation, it is possible to obtain a three-dimensional object having sufficient mechanical properties and excellent shape stability. In other words, it is possible to produce three-dimensional objects of various shapes using the photopolymerizable resin composition.

[0043] If necessary, the adherend may be heated, which can promote the curing reaction of the photocurable resin composition.

[0044] [Example] The present invention will be described below with reference to examples, but the present invention is not limited to the following examples.

[0045] <Photocurable resin compositions A1 to A3 and B1 to B2> The resin components were mixed in the mass ratios shown in Table 1, and an inorganic filler was further added to the resin components and kneaded to prepare resin compositions A1 to A3, B1, and B2. The exposure dose was 3000 mJ / cm. 2 , illuminance 100mW / cm 2 The resin was exposed to UV light under the following conditions and cured.

[0046] (Composition) Bisphenol F type epoxy: Bisphenol F type liquid epoxy resin Bisphenol A epoxy: Bisphenol A liquid epoxy resin Cycloaliphatic Epoxy: 3,4-Epoxycyclohexylmethyl(3,4-epoxy)cyclohexanecarboxylate Photoreactive polymerization initiator: Triarylsulfonium anion salt Silica: Fused spherical silica particles

[0047] The heat shrinkage stress performance of the cured resin composition was evaluated. Here, the linear expansion coefficient was measured by TMA (Thermomechanical Analysis). If the linear expansion coefficient is less than 25 ppm / K, it can be said that the heat shrinkage stress performance is very good.

[0048] [Table 1]

[0049] As shown in the results in Table 1, the resin compositions A1 to A3, which contain 75% by mass or more of inorganic filler, were photocurable resin compositions with good heat shrinkage stress performance. On the other hand, the resin compositions B1 to B2, which contain 70% by mass of inorganic filler, had poor heat shrinkage stress performance. From the above, it can be said that in order to achieve excellent heat shrinkage stress performance, it is desirable for the photocurable resin composition to contain 75% by mass or more of inorganic filler.

[0050] <Examples 1 to 5 and Comparative Examples 1 to 3> Resin composition A1 shown in Table 1 was applied onto a printed circuit board and cured by the following coating and exposure methods A to C, and the aspect ratio performance was evaluated to see whether a useful shape could be formed.

[0051] (Coating and Exposure Method A) Resin composition A1 was discharged from a nozzle with a diameter of 0.5 mm using a jet dispenser with a nozzle and a liquid reservoir heated to 80° C. The nozzle was scanned while moving horizontally in the X direction at a speed of 30 mm / sec. The discharged resin composition A1 was exposed to an exposure dose of 3000 mJ / cm within 5 seconds. 2 , illuminance 100mW / cm 2 In order to form a shape with a high aspect ratio, the resin composition A1 was cured by one set of coating and exposure, or in some cases three sets of coating and exposure.

[0052] (Coating and Exposure Method B) Resin composition A1 was discharged from a nozzle with a diameter of 0.5 mm using a jet dispenser with a nozzle and a liquid reservoir heated to 80° C. The nozzle was scanned while moving horizontally in the X direction at a speed of 50 mm / sec. The discharged resin composition A1 was exposed to an exposure dose of 3000 mJ / cm within 5 seconds. 2 , illuminance 100mW / cm 2 In order to form a shape with a high aspect ratio, one coating and one exposure were counted as one set, and in some cases, three or four sets of coating and exposure were performed to cure the resin composition A1.

[0053] (Coating and Exposure Method C) Resin composition A1 was discharged from a nozzle having a diameter of 0.5 mm at 25° C. The discharged resin composition A1 was applied five times in some cases, and 60 seconds after application, the exposure dose was 3000 mJ / cm 2 . 2 , illuminance 100mW / cm 2 The resin was exposed to UV light under the following conditions and cured.

[0054] The height and width of the cured product of the resin composition A1 applied and cured on the substrate were measured and calculated as (height / width = aspect ratio). The aspect ratio performance was judged as good (◯) or insufficient (×) according to the following criteria. 〇: Aspect ratio less than 0.30, ×: Aspect ratio 0.30 or more

[0055] [Table 2]

[0056] As shown in the results in Table 2, when coating exposure methods A and B were used, the aspect ratio was 0.44 or more. When the number of coatings was three or more, the aspect ratio reached a maximum of 2.73, and it was possible to form free shapes by increasing the number of coatings or controlling the coating speed. On the other hand, when coating exposure method C was used, the maximum aspect ratio was 0.25, making it difficult to form free shapes with high aspect ratios.

[0057] From the above, it can be seen that even when using a photocurable resin composition containing 75% by mass or more of inorganic filler, a cured product with excellent mechanical properties and shape stability can be formed by employing a process in which the photocurable resin composition is heated and discharged from the nozzle of an application device to apply it to an adherend, and then irradiated with light. [Industrial Applicability]

[0058] The photocurable resin composition according to the present disclosure can be used for various purposes.

Claims

1. A photocurable resin composition which is discharged in a heated state from a nozzle of an application device, applied to an adherend, and irradiated with light, A reactive compound, a photopolymerization initiator, and an inorganic filler are included, The reactive compound has radical polymerizability or cationic polymerizability, The photopolymerization initiator is activated by light irradiation, The photocurable resin composition has a content of the inorganic filler of 75 mass% or more.

2. The photocurable resin composition according to claim 1 , wherein the inorganic filler is silica particles.

3. The photocurable resin composition according to claim 2 , wherein the content of the silica particles is 80% by mass or more.

4. The photocurable resin composition according to any one of claims 1 to 3, wherein the reactive compound is at least one selected from the group consisting of an epoxy resin, an oxetane compound, or an acrylic monomer.

5. The photocurable resin composition according to any one of claims 1 to 3, which produces a cured product having a linear expansion coefficient of 25 ppm / K or less upon irradiation with light.

6. (i) a heating step of heating the photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device onto an adherend; (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light; Equipped with The photocurable resin composition includes a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerizability or cationic polymerizability, and the photopolymerization initiator is activated by light irradiation.

7. The method for curing a photocurable resin composition according to claim 6 , wherein the content of the inorganic filler in the photocurable resin composition is 40 mass % or more.

8. 7. The method for curing a photocurable resin composition according to claim 6, wherein the heating step is a step of heating the photocurable resin composition to a temperature of 50°C or higher and 100°C or lower.

9. 9. The method for curing a photocurable resin composition according to claim 6, wherein in the heating step, the photocurable resin composition is heated in a liquid reservoir provided in the coating device.

10. The application device is a jet dispenser, The method for curing a photocurable resin composition according to any one of claims 6 to 8, wherein the photocurable resin composition is discharged onto the adherend in the form of spots or lines.

11. The method for curing a photocurable resin composition according to any one of claims 6 to 8, wherein in the light irradiation step, the coating film of the photocurable resin composition is irradiated with light within 30 seconds after the photocurable resin composition is discharged from the nozzle.

12. The method for curing a photocurable resin composition according to any one of claims 6 to 8, wherein a thickness of one layer of the coating film of the photocurable resin composition applied to the adherend is 2 mm or less.

13. The method for curing a photocurable resin composition according to any one of claims 6 to 8, wherein the photocurable resin composition applied to the adherend and cured is used as a new adherend, and the heating step, the application step, and the light irradiation step are repeated.

14. (i) a heating step of heating the photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device onto an adherend; (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light; Equipped with The adherend includes a substrate and an electronic component mounted on the substrate, The photocurable resin composition includes a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerizability or cationic polymerizability, the photopolymerization initiator being activated by light irradiation, the substrate and the electronic component are bonded to each other by a cured product of the photocurable resin composition.

15. (i) a heating step of heating the photocurable resin composition; (ii) a coating step of discharging the heated photocurable resin composition from a nozzle of a coating device onto an adherend; (iii) a light irradiation step of irradiating the heated photocurable resin composition discharged from the nozzle with light; Equipped with The photocurable resin composition includes a reactive compound, a photopolymerization initiator, and an inorganic filler, the reactive compound having radical polymerizability or cationic polymerizability, the photopolymerization initiator being activated by light irradiation, the photocurable resin composition applied to the adherend and cured is used as a new adherend, and the heating step, the application step, and the light irradiation step are repeated in this method for manufacturing a three-dimensional object.

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