Photocurable resin composition, optical member, method for producing optical member, light-emitting device, and method for producing light-emitting device

Abstract

Provided is a photocurable resin composition which has a high refractive index of a cured product and is capable of suppressing breakage of the cured product during deformation. The photocurable resin composition contains a radical polymerizable compound (A), a photoradical polymerization initiator (B), and an inorganic filler (C). The radically polymerizable compound (A) contains: a first polyfunctional radically polymerizable compound (A1) having a structure in which an allyloxyalkyl group is bonded to a 2-position carbon of an acrylate; a monofunctional radical polymerizable compound (A2) having a nitrogen atom; and a second polyfunctional radical polymerizable compound (A3) different from the first polyfunctional radical polymerizable compound (A1). The ratio of the first polyfunctional radically polymerizable compound (A1) to the radically polymerizable compound (A) is from 20% by mass to 98% by mass (inclusive).

Description

Technical Field

[0001] The present disclosure relates to a photocurable resin composition, an optical component, a method for manufacturing an optical component, a light-emitting device, and a method for manufacturing a light-emitting device. More specifically, the present disclosure relates to a photocurable resin composition containing a radically polymerizable compound and a photo radical polymerization initiator, an optical component made of the above photocurable resin composition, a method for manufacturing an optical component using the above photocurable resin composition, a light-emitting device including the above optical component, and a method for manufacturing the above light-emitting device. Background Art

[0002] In a light-emitting device having a light-emitting element such as an organic EL element as a light source, for example, an organic EL element is disposed on a support substrate, a transparent substrate is disposed so as to face the support substrate, and a transparent sealing material is filled between the support substrate and the transparent substrate.

[0003] For example, Patent Document 1 discloses a curable composition containing a naphthalene compound having a structure in which two or more vinyl groups are present in one molecule and the vinyl groups are directly bonded to the benzene ring of naphthalene, such as 1,3-divinylnaphthalene, and a polymerization initiator, and containing the naphthalene compound in a range of 20 parts by mass to 99 parts by mass with respect to 100 parts by mass of the curable composition. According to the disclosure of Patent Document 1, this curable composition is useful as a sealing material for organic electroluminescent elements that can be applied to uses such as display devices and lighting devices, has a high refractive index while maintaining the curing performance as a sealing material, and is excellent in coatability and transparency.

[0004] Prior Art Documents

[0005] Patent Documents

[0006] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2020-26515 Summary of the Invention

[0007] An object of the present disclosure is to provide a photocurable resin composition in which a cured product has a high refractive index and the breakage of the cured product during deformation can be suppressed, an optical component made of the above photocurable resin composition, a method for manufacturing an optical component using the above photocurable resin composition, a light-emitting device including the above optical component, and a method for manufacturing a light-emitting device.

[0008] One embodiment of the photocurable resin composition of the present disclosure contains a radically polymerizable compound (A), a photo radical polymerization initiator (B), and an inorganic filler (C). The radically polymerizable compound (A) contains: a first polyfunctional radically polymerizable compound (A1) having a structure in which an allyloxyalkyl group is bonded to the 2-position carbon of an acrylate; a monofunctional radically polymerizable compound (A2) having a nitrogen atom; and a second polyfunctional radically polymerizable compound (A3) different from the above-mentioned first polyfunctional radically polymerizable compound (A1). The proportion of the above-mentioned first polyfunctional radically polymerizable compound (A1) is 20% by mass or more and 98% by mass or less with respect to the above-mentioned radically polymerizable compound (A).

[0009] One embodiment of the optical component of the present disclosure includes a cured product of the above-mentioned photocurable resin composition.

[0010] One embodiment of the method for manufacturing an optical component of the present disclosure includes a step of forming the above-mentioned photocurable resin composition by an inkjet method and then irradiating the above-mentioned photocurable resin composition with light to cure it.

[0011] One embodiment of the light-emitting device of the present disclosure includes a light source and an optical component that transmits the light emitted by the above-mentioned light source, and the above-mentioned optical component includes a cured product of the above-mentioned photocurable resin composition.

[0012] One embodiment of the method for manufacturing a light-emitting device of the present disclosure is a method for manufacturing a light-emitting device including a light source and an optical component that transmits the light emitted by the above-mentioned light source. This method includes a step of manufacturing the above-mentioned optical component by the above-mentioned method. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic cross-sectional view showing a light-emitting device in one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] According to the investigation by the inventors, if the refractive index of an optical component such as a sealing material of an organic EL element is increased, the luminous efficiency of a light-emitting device including the optical component can be improved.

[0015] However, when using the curable composition disclosed in Patent Document 1 (Japanese Unexamined Patent Application Publication No. 2020-26515) to produce a sealing material, although the refractive index of the sealing material is increased, the flexibility of the cured product of the curable composition becomes low.

[0016] In recent years, deformable light-emitting devices represented by foldable displays have been continuously provided. The inventors have studied the provision of an optical component having a high refractive index in a deformable light-emitting device. However, in this case, if the light-emitting device is deformed, the optical component is likely to be damaged.

[0017] Therefore, in order to develop a photocurable resin composition in which the cured product has a high refractive index and the breakage of the cured product during deformation can be suppressed, the inventor has completed this application. However, the content of the present disclosure is not construed restrictively based on the above development process.

[0018] Refer to Figure 1 An embodiment of the present disclosure will be described. It should be noted that the following embodiments are only a part of various embodiments of the present disclosure. In addition, the following embodiments can be variously modified according to design and the like as long as the object of the present disclosure can be achieved. The figures referred to below are schematic figures, and the dimensional ratios of the constituent elements in the figures do not necessarily reflect the actual dimensional ratios.

[0019] The photocurable resin composition of the present embodiment (hereinafter, also referred to as composition (X)) contains a radically polymerizable compound (A), a photo radical polymerization initiator (B), and an inorganic filler (C). The radically polymerizable compound (A) contains: a first polyfunctional radically polymerizable compound (A1) having a structure in which an allyloxyalkyl group is bonded to the 2-position carbon of acrylate; a monofunctional radically polymerizable compound (A2) having a nitrogen atom; and a second polyfunctional radically polymerizable compound (A3) different from the first polyfunctional radically polymerizable compound (A1). The proportion of the first polyfunctional radically polymerizable compound (A1) is 20% by mass or more and 98% by mass or less with respect to the radically polymerizable compound (A).

[0020] According to the present embodiment, the cured product obtained by curing the composition (X) has a high refractive index. In addition, although the composition (X) contains the inorganic filler (C), breakage of the cured product during deformation can be suppressed. Therefore, if an optical component is made of the composition (X), the luminous efficiency of a light-emitting device including the optical component can be improved. The improvement in luminous efficiency is because, particularly when the optical component is overlapped with a layer made of an inorganic material such as silicon nitride (hereinafter, also referred to as an inorganic film) in the light-emitting device, the refractive index difference between the optical component and the inorganic film becomes smaller.

[0021] The first polyfunctional radically polymerizable compound (A1) will be described in more detail. As described above, the compound (A1) has a structure in which an allyloxyalkyl group is bonded to the 2-position carbon of acrylate.

[0022] The first polyfunctional radically polymerizable compound (A1) is represented by the following structural formula, for example. In the following structural formula, R1 is an alkyl group, and X is an allyloxyalkyl group. The number of carbon atoms of R1 is, for example, 1 or more and 20 or less.

[0023] [Chemical formula 1]

[0024]

[0025] The allyloxyalkyl group can be represented by the following structural formula. R is an alkylene group. The number of carbon atoms in R is, for example, 1 or more and 3 or less. When R contains a main chain and side chains, the number of carbon atoms in the main chain of R is, for example, 1 or more and 3 or less. The acrylate is, for example, an ester of acrylic acid and an alkyl alcohol, and the number of carbon atoms in the alkyl alcohol at this time is, for example, 1 or more and 20 or less.

[0026] [Chemical formula 2]

[0027]

[0028] It should be noted that the structure in which an allyloxyalkyl group is bonded to the 2-position carbon of the acrylate only defines the structure of the compound (A1), and does not define the method for synthesizing the compound (A1).

[0029] The first polyfunctional radically polymerizable compound (A1) inhibits the breakage of the cured product. It is presumed that the reason is that in the polymer formed by the polymerization of the radically polymerizable compound (A), a heterocyclic ring containing an oxygen atom is formed by the intramolecular reaction of the radically polymerizable unsaturated bond in the acrylate moiety of the first polyfunctional radically polymerizable compound (A1) and the radically polymerizable unsaturated bond in the allyloxyalkyl group, and this heterocyclic ring imparts strength and flexibility to the cured product. In addition, since the first polyfunctional radically polymerizable compound (A1) before polymerization does not have the above heterocyclic ring, the first polyfunctional radically polymerizable compound (A1) is not likely to increase the viscosity of the composition (X). Therefore, the first polyfunctional radically polymerizable compound (A1) is not likely to deteriorate the moldability of the composition (X).

[0030] The first polyfunctional radically polymerizable compound (A1) preferably contains methyl 2-(allyloxymethyl)acrylate represented by the following formula (1).

[0031] [Chemical formula 3]

[0032]

[0033] If the first polyfunctional radically polymerizable compound (A1) contains methyl 2-(allyloxymethyl)acrylate, the polymer of the radically polymerizable compound (A) can contain the following structure represented by formula (11) derived from methyl 2-(allyloxymethyl)acrylate. It is presumed that by the structure represented by formula (11), appropriate strength and flexibility can be imparted to the cured product.

[0034] [Chemical formula 4]

[0035]

[0036] The proportion of the first polyfunctional radically polymerizable compound (A1) in the composition (X) is 20% by mass or more and 98% by mass or less with respect to the radically polymerizable compound (A). By making this proportion 20% by mass or more, the flexibility of the cured product can be improved. In addition, by making this proportion 98% by mass or less, the refractive index of the cured product can be sufficiently increased. This proportion is preferably 30% by mass or more, more preferably 40% by mass or more. In addition, this proportion is preferably 95% by mass or less, more preferably 90% by mass or less.

[0037] A monofunctional radically polymerizable compound (A2) having a nitrogen atom will be described. The monofunctional radically polymerizable compound (A2) has only one radically polymerizable functional group in the molecule and has a nitrogen atom. The monofunctional radically polymerizable compound (A2) can improve the adhesion of the cured product to the inorganic film. Therefore, when the cured product deforms together with the inorganic film in a state where the cured product and the inorganic film overlap, the cured product is not easily peeled off from the inorganic film. As a result, breakage of the cured product is further suppressed. The monofunctional radically polymerizable compound (A2) can improve the wettability of the composition (X) with the inorganic film. Therefore, it is easy to coat the composition (X) on the inorganic film for forming. In addition, the monofunctional radically polymerizable compound (A2) can have a low viscosity. Therefore, the monofunctional radically polymerizable compound (A2) is not likely to deteriorate the formability of the composition (X) or can improve the formability of the composition (X). In addition, the monofunctional radically polymerizable compound (A2) can have high reactivity. Therefore, when the composition (X) is cured, unreacted components are not likely to remain, and thus generation of outgassing from the cured product can be suppressed.

[0038] The monofunctional radically polymerizable compound (A2) preferably contains at least one selected from a compound having an oxazoline ring, a compound having a morpholine ring, a compound having a dimethylamino group, a compound having a diethylamino group, and a compound having a pyrrolidone ring. In this case, the adhesion between the cured product and the inorganic film can be further improved.

[0039] Examples of the compound having an oxazoline ring include vinylmethyl oxazolidinone. Examples of the compound having a morpholine ring include at least one selected from acryloylmorpholine and 4-morpholinyl acrylate. Examples of the compound having a dimethylamino group include at least one selected from dimethylacrylamide, dimethylmethacrylamide, dimethylaminopropylacrylamide, and dimethylaminopropylmethacrylamide. Examples of the compound having a diethylamino group include at least one selected from diethylacrylamide and diethylmethacrylamide. Examples of the compound having a pyrrolidone ring include N-vinyl-2-pyrrolidone.

[0040] It should be noted that the compounds that the monofunctional radically polymerizable compound (A2) can contain are not limited to the above. For example, the monofunctional radically polymerizable compound (A2) can contain compounds having a piperidine ring such as pentamethylpiperidyl methacrylate.

[0041] Particularly preferably, the monofunctional radically polymerizable compound (A2) contains vinyl methyl oxazolidinone. In this case, breakage of the cured product can be further suppressed. It is presumed that this is because by introducing an ester skeleton into the polymer of the radically polymerizable compound (A) using vinyl methyl oxazolidinone, the strength and flexibility of the cured product can be improved.

[0042] With respect to 100 parts by mass of the radically polymerizable compound (A), the proportion of the monofunctional radically polymerizable compound (A2) in the composition (X) is preferably 1% by mass or more and 80% by mass or less. If this proportion is 1% by mass or more, breakage during deformation of the cured product can be further suppressed. If this proportion is 85% by mass or less, evolution of gas from the cured product can be suppressed, and problems such as swelling and peeling are less likely to occur in optical components and the like containing the cured product. This proportion is more preferably 4% by mass or more. In addition, this proportion is more preferably 20% by mass or less, and further preferably 10% by mass or less.

[0043] The second polyfunctional radically polymerizable compound (A3) will be described. The second polyfunctional radically polymerizable compound (A3) is a compound having two or more radically polymerizable functional groups in one molecule. However, the first polyfunctional radically polymerizable compound (A1) does not include the second polyfunctional radically polymerizable compound (A3). The second polyfunctional radically polymerizable compound (A3) can improve the reactivity of the composition (X). Therefore, evolution of gas from the cured product can be suppressed. The second polyfunctional radically polymerizable compound (A3) can also increase the crosslink density of the polymer of the radically polymerizable compound (A). Therefore, the glass transition temperature of the cured product can be increased, thereby improving the heat resistance of the cured product.

[0044] The second polyfunctional radically polymerizable compound (A3) contains, for example, at least one selected from the group consisting of glycerol triacrylate, 1,3-butanediol di(meth)acrylate, 1,4-butanediol oligoacrylate, diethylene glycol diacrylate, 1,6-hexanediol oligoacrylate, neopentyl glycol diacrylate, triethylene glycol diacrylate, tripropylene glycol diacrylate, dipropylene glycol diacrylate, cyclohexanedimethanol diacrylate, tricyclodecane dimethanol diacrylate, bisphenol A polyethoxy diacrylate, bisphenol F polyethoxy diacrylate, pentaerythritol tetraacrylate, propoxylated(2) neopentyl glycol diacrylate, trimethylolpropane triacrylate, tris(2-hydroxyethyl) isocyanurate triacrylate, pentaerythritol triacrylate, ethoxylated(3) trimethylolpropane triacrylate, propoxylated(3) glycerol triacrylate, pentaerythritol tetraacrylate, bis(trimethylolpropane) tetraacrylate, ethoxylated(4) pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, 2-(2-ethoxyethoxy)ethyl acrylate, hexanediol diacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, tripropylene glycol triacrylate, dipentaerythritol hexaacrylate, ethylene glycol diacrylate, 1,6-hexanediol diacrylate, ethoxylated 1,6-hexanediol diacrylate, polypropylene glycol diacrylate, 1,4-butanediol diacrylate, 1,9-nonanediol diacrylate, tetraethylene glycol diacrylate, 2-n-butyl-2-ethyl-1,3-propanediol diacrylate, hydroxypivalic acid neopentyl glycol diacrylate, hydroxypivalic acid trimethylolpropane triacrylate, ethoxylated trisacrylate phosphate, ethoxylated tripropylene glycol diacrylate, neopentyl glycol-modified trimethylolpropane diacrylate, stearic acid-modified pentaerythritol diacrylate, tetramethylolpropane triacrylate, tetramethylolmethane triacrylate, caprolactone-modified trimethylolpropane triacrylate, propoxylated glycerol triacrylate, tetramethylolmethane tetraacrylate, ethoxylated pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, caprolactone-modified dipentaerythritol hexaacrylate, dipentaerythritol hydroxypentaacrylate, neopentyl glycol oligoacrylate, trimethylolpropane oligoacrylate, pentaerythritol oligoacrylate, ethoxylated neopentyl glycol di(meth)acrylate, propoxylated neopentyl glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, ethoxylated trimethylolpropane triacrylate, propoxylated trimethylolpropane triacrylate, and 2-(2-vinyloxyethoxy)ethyl acrylate, etc.

[0045] The second polyfunctional radically polymerizable compound (A3) particularly preferably contains glycerol triacrylate. Glycerol triacrylate is polyfunctional and has a low viscosity, so that the composition (X) can be made to have a low viscosity. Particularly when the composition (X) is ejected by an inkjet method, the second polyfunctional radically polymerizable compound (A3) preferably contains glycerol triacrylate.

[0046] The proportion of the second polyfunctional radically polymerizable compound (A3) in the composition (X) is preferably 0.5% by mass or more and 25% by mass or less with respect to the radically polymerizable compound (A). This proportion is more preferably 1% by mass or more. Further, this proportion is more preferably 20% by mass or less.

[0047] The radically polymerizable compound (A) may contain components other than the above within a range that does not significantly hinder the effects of the present embodiment. For example, the radically polymerizable compound (A) may contain a monofunctional radically polymerizable compound (A4) that is different from the above-mentioned monofunctional radically polymerizable compound (A2) and has only one radically polymerizable functional group in the molecule.

[0048] The monofunctional radically polymerizable compound (A4) contains, for example, at least one compound selected from tetrahydrofurfuryl acrylate, isobornyl acrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, isobutyl acrylate, tert-butyl acrylate, isooctyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, 3-methoxybutyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate, ethoxydiethylene glycol acrylate, methoxydioxylethyl acrylate, ethyldiethylene glycol acrylate, cyclic trimethylolpropane formal monoacrylate, imide acrylate, isoamyl acrylate, ethoxylated succinic acid acrylate, trifluoroethyl acrylate, ω-carboxypolycaprolactone monoacrylate, cyclohexyl acrylate, 2-(2-ethoxyethoxy)ethyl acrylate, stearyl acrylate, diethylene glycol monobutyl ether acrylate, lauryl acrylate, isodecyl acrylate, 3,3,5-trimethylcyclohexanol acrylate, isooctyl acrylate, octyl / decyl acrylate, tridecyl acrylate, caprolactone acrylate, ethoxylated (4) nonylphenol acrylate, methoxypolyethylene glycol (350) monoacrylate, methoxypolyethylene glycol (550) monoacrylate, phenoxyethyl acrylate, (meth)cyclohexyl acrylate, (meth)dicyclopentyl acrylate, (meth)tetrahydrofurfuryl acrylate, benzyl acrylate, methylphenoxyethyl acrylate, 4-tert-butylcyclohexyl acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, tribromophenyl acrylate, ethoxylated tribromophenyl acrylate, 2-phenoxyethyl acrylate, ethylene oxide adduct of 2-phenoxyethyl acrylate, propylene oxide adduct of 2-phenoxyethyl acrylate, dicyclopentyl acrylate, phenoxydiethylene glycol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 1,4-cyclohexanedimethanol monoacrylate, 3-methacryloxymethyl epoxyhexane, and 3-acryloxymethyl epoxyhexane.

[0049] The monofunctional radically polymerizable compound (A4) may contain a monofunctional radically polymerizable compound (A41) having two or more aromatic rings. The monofunctional radically polymerizable compound (A41) can increase the refractive index of the cured product.

[0050] The monofunctional radically polymerizable compound (A41) having two aromatic rings contains, for example, at least one of the compound represented by the following formula (2) and the compound represented by the following formula (3).

[0051] [Chemical formula 5]

[0052]

[0053] [Chemical formula 6]

[0054]

[0055] In formula (2), X1 is hydrogen or methyl, Y1 is a single bond or an alkylene group having 1 to 6 carbon atoms, Z1 is a single bond, S or O, R1 is H or methyl, L1 is a single bond, an ester bond or a thioester bond, n is 1 or 2. Among them, when L1 is a single bond, n is 1 and m is 6 or 7. In formula (3), X2 is a single bond or O, Z2 is a single bond or O, R2 is H or methyl, Y2 is a single bond or an alkylene group having 1 to 6 carbon atoms, and L2 is a single bond or an ester bond.

[0056] The monofunctional radically polymerizable compound (A41) particularly preferably contains a compound (A411) represented by the following formula (31). In formula (31), R1 is H or CH3, X is O or S, and Z is a single bond or a divalent saturated hydrocarbon group. When Z is a divalent saturated hydrocarbon group, the divalent saturated hydrocarbon group may be linear or branched.

[0057] [Chemical formula 7]

[0058]

[0059] The compound (A411) can increase the refractive index of the cured product, and can also increase the strength and flexibility of the cured product. Therefore, breakage of the cured product can be further suppressed. More preferably, Z in formula (31) is a single bond, or Z is a divalent hydrocarbon group and the divalent saturated hydrocarbon group has 1 or more and 5 or less carbon atoms. In this case, the compound (A411) is not likely to particularly increase the viscosity of the composition (X), so the compound (A411) is not likely to particularly deteriorate the formability of the composition (X).

[0060] When the radically polymerizable compound (A) contains the monofunctional radically polymerizable compound (A41), the proportion of the monofunctional radically polymerizable compound (A41) is preferably 10% by mass or more and 40% by mass or less relative to the radically polymerizable compound (A). In particular, when the radically polymerizable compound (A) contains the compound (A411), the proportion of the compound (A411) is preferably 10% by mass or more and 60% by mass or less relative to the radically polymerizable compound (A). Since the compound (A411) has a biphenyl structure, its effect of increasing the hardness of the cured product is lower than that of a compound having a naphthalene structure. Therefore, even if the proportion of the compound (A411) is 60% by mass, the compound (A411) is not likely to excessively increase the hardness of the cured product.

[0061] The photo-radical polymerization initiator (B) will be described. The photo-radical polymerization initiator (B) contains, for example, at least one compound selected from aromatic ketones, acylphosphine oxide compounds, aromatic onium salt compounds, organic peroxides, sulfur compounds (such as thioxanthone compounds and compounds containing thiophenyl groups), hexaarylbiimidazole compounds, oxime ester compounds, borate ester compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon-halogen bond, and alkylamine compounds.

[0062] The proportion of the photo-radical polymerization initiator (B) relative to the radically polymerizable compound (A) is preferably 6% by mass or more. In this case, the composition (X) can have good photocurability and can also have good photocurability in an air atmosphere. This proportion is more preferably 7% by mass or more, and further preferably 8% by mass or more. Additionally, this proportion is, for example, 30% by mass or less, preferably 20% by mass or less, and further preferably 18% by mass or less.

[0063] The photo-radical polymerization initiator (B) may contain a photo-radical polymerization initiator having photo-bleaching properties. In this case, the cured product of the composition (X) can have good light transmittance. The proportion of the photo-radical polymerization initiator having photo-bleaching properties relative to the radically polymerizable compound (A) is preferably 3% by mass or more. This proportion is more preferably 7% by mass or more, and further preferably 8% by mass or more. Additionally, this proportion is, for example, 30% by mass or less, preferably 25% by mass or less, and further preferably 20% by mass or less.

[0064] The photo-radical polymerization initiator having photo-bleaching properties contains, for example, at least one of the compounds having photo-bleaching properties among acylphosphine oxide-based photoinitiators and oxime ester-based photoinitiators.

[0065] The photo-radical polymerization initiator (B) may contain a component having a sensitizer skeleton in the molecule. The sensitizer skeleton contains, for example, at least one of a 9H-thioxanthen-9-one skeleton and an anthracene skeleton. That is, the photo-radical polymerization initiator (B) preferably contains a component having at least one of a 9H-thioxanthen-9-one skeleton and an anthracene skeleton.

[0066] The photo-radical polymerization initiator (B) preferably contains a compound (B1) that is excited by absorbing light with a wavelength of 395 nm. In this case, the reactivity of the composition (X) when irradiated with ultraviolet light can be improved. The absorption coefficient of the light with a wavelength of 395 nm of the sample obtained by dissolving the compound (B1) in acetonitrile at a concentration of 0.01 g / L is preferably 0.1 mL / g·cm or more.

[0067] The proportion of the compound (B1) relative to the photo-radical polymerization initiator (B) is preferably 40% by mass or more. In this case, the reactivity of the composition (X) when irradiated with ultraviolet rays can be further improved. This proportion is more preferably 60% by mass or more, and even more preferably 80% by mass or more. The upper limit of this proportion is not particularly defined and can be 100% by mass. That is, this proportion is, for example, 100% by mass or less.

[0068] When the photo-radical polymerization initiator (B) contains the compound (B1), the compound (B1) contains, for example, at least one selected from 2-benzyl-2-(dimethylamino)-1-(4-morpholinophenyl)-1-butanone (e.g., Irgacure 369 manufactured by BASF), phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide (e.g., Irgacure 819 manufactured by BASF), 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (e.g., Omnirad TPO H manufactured by IGM RESINS B.V.), and bis(2,4-cyclopentadienyl)bis[2,6-difluoro-3-(1-pyridyl)phenyl]titanium(IV) (e.g., Irgacure 784 manufactured by BASF).

[0069] In addition to the photo-radical polymerization initiator (B), the composition (X) may contain a polymerization accelerator. The polymerization accelerator contains, for example, amine compounds such as ethyl p-dimethylaminobenzoate, 2-ethylhexyl p-dimethylaminobenzoate, methyl p-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, and butoxyethyl p-dimethylaminobenzoate. It should be noted that the components that the polymerization accelerator can contain are not limited to the above components.

[0070] The inorganic filler (C) will be described. The inorganic filler (C) can increase the refractive index of the cured product. In addition, in the present embodiment, even when the composition (X) contains the inorganic filler (C), breakage during deformation of the cured product can be suppressed.

[0071] The inorganic filler (C) is preferably of nano size. In this case, good transparency (visible light transmittance) of the cured product can be maintained, and the cured product can have a high refractive index. Nano size means that the average particle diameter is 1 nm or more and 1000 nm or less. The average particle diameter of the inorganic filler (C) is preferably 30 nm or less, more preferably 20 nm or less. In addition, this average particle diameter is preferably 5 nm or more, more preferably 10 nm or more. It should be noted that this average particle diameter is the median diameter calculated from the measurement results based on the dynamic light scattering method, that is, the cumulative 50% particle diameter (D50). It should be noted that as the measuring device, the Nanotrac Wave series of Microtrac BEL Co., Ltd. can be used.

[0072] The inorganic filler (C) preferably contains at least one of zirconia and titanium oxide. In this case, the refractive index of the cured product can be further increased.

[0073] Titanium oxide is preferably coated. In this case, the deterioration of the organic components caused by the photocatalytic action of titanium oxide is suppressed. Titanium oxide is coated with, for example, aluminum, aluminum and zirconium, or aluminum and silicon.

[0074] With respect to the total of the radically polymerizable compound (A), the photo-radical polymerization initiator (B), and the inorganic filler (C), the proportion of the inorganic filler (C) is preferably 1% by volume or more and 25% by volume or less. If this proportion is 1% by volume or more, the refractive index of the cured product can be further increased. If this proportion is 25% by volume or less, breakage during deformation of the cured product can be further suppressed. This proportion is more preferably 5% by volume or more, and further preferably 10% by volume or more. In addition, this proportion is more preferably 22% by volume or less, and further preferably 17% by volume or less.

[0075] The composition (X) preferably does not contain a solvent or the solvent content is 1% by mass or less. In this case, outgassing from the solvent is less likely to occur from the composition (X) and the cured product of the composition (X). In addition, when manufacturing an optical component and a light-emitting device, a drying process for removing the solvent from the composition (X) and the cured product may not be required. A drying process for removing the solvent from at least one of the composition (X) and the cured product can be performed, and in this case, at least one of a reduction in the heating temperature and a shortening of the heating time in the drying process can be achieved. Therefore, outgassing is less likely to occur from the optical component without reducing the manufacturing efficiency of the optical component and the light-emitting device. In addition, particularly when the composition (X) is ejected by an inkjet method for forming, a reduction in thickness due to volatilization of the solvent from the formed composition (X) is less likely to occur, and thus a reduction in the thickness of the optical component is less likely to occur. Therefore, while ejecting the composition (X) by an inkjet method for forming, the thickness of the optical component can be ensured to be as large as possible. The solvent content is more preferably 0.5% by mass or less, further preferably 0.3% by mass or less, and particularly preferably 0.1% by mass or less. Particularly preferably, the composition (X) does not contain a solvent or contains only an unavoidably mixed solvent.

[0076] The composition (X) may further contain optional additives such as a moisture-absorbing material, a dispersant, and a silane coupling agent other than those described above within a range that does not significantly impede the object of the present disclosure.

[0077] In the present embodiment, the composition (X) can be used to manufacture optical components. An optical component is a component disposed on the optical path of light in an optical system. In the present embodiment, the composition (X) can preferably be used to manufacture optical components that transmit light. However, the use of the composition (X) is not limited to the manufacture of optical components, and the composition (X) can also be applied to various uses that utilize its characteristics.

[0078] The refractive index of the cured product of the composition (X) is preferably 1.58 or more. That is, it is preferable to increase the refractive index of the cured product by using the present embodiment so that the cured product has a refractive index of 1.58 or more. In this case, particularly when an optical component made of the composition (X) is overlapped with an inorganic film in a light-emitting device, the luminous efficiency of the light-emitting device can be particularly improved. The refractive index is more preferably 1.60 or more, and further preferably 1.62 or more. In addition, the refractive index is preferably 1.70 or less, more preferably 1.67 or less, further preferably 1.65 or less, and particularly preferably 1.62 or less. It should be noted that the refractive index in the present disclosure refers to the refractive index of light with a wavelength of 589 nm in an atmosphere at 25°C.

[0079] In the present embodiment, the composition (X) can have a low viscosity. Therefore, the formability of the composition (X) is good. For example, the composition (X) can be ejected by an inkjet method for forming. When manufacturing a cured product or an optical component from the composition (X), it is preferable to eject the composition (X) by an inkjet method for forming. That is, the composition (X) is preferably used for inkjet forming. In this case, the cured product and optical component of the composition (X) can be manufactured with good positional accuracy. In addition, when the composition (X) is formed by an inkjet method, foreign substances are less likely to be mixed into the composition (X) and its cured product compared to the case of forming by a printing method accompanied by contact such as a screen printing method. Therefore, the qualified rate when manufacturing an optical component is less likely to deteriorate.

[0080] The viscosity of the composition (X) at 40°C is preferably 16 mPa·s or less. In this case, regardless of the viscosity of the composition (X) at normal temperature, as long as the composition (X) is slightly heated, its viscosity can be reduced. Therefore, if heating is performed, the composition (X) can be easily formed, and particularly, it can be easily formed by ejection by an inkjet method. In addition, the viscosity of the composition (X) can be reduced without significantly heating the composition (X), so the composition of the composition (X) is less likely to change due to the volatilization of the components in the composition (X). The viscosity is also preferably 1 mPa·s or more, and still more preferably 5 mPa·s or more.

[0081] The viscosity of the composition (X) at 25°C is preferably 50 mPa·s or less. The viscosity of the composition (X) at 25°C is more preferably 40 mPa·s or less, further preferably 30 mPa·s or less, and particularly preferably 28 mPa·s or less. The viscosity is also preferably 1 mPa·s or more, more preferably 5 mPa·s or more, still more preferably 10 mPa·s or more, and further preferably 20 mPa·s or more. In these cases, the composition (X) can be easily formed at normal temperature, and in particular, the composition (X) can be easily formed by an inkjet method.

[0082] Such a low viscosity of the composition (X) can be achieved by appropriately adjusting the composition of the radically polymerizable compound (A) within the range described above. It should be noted that the method and conditions for measuring the viscosity of the composition (X) are described in detail in the Examples section below.

[0083] The proportion of the evolved gas generated when the cured product of the composition (X) is heated at 110°C for 30 minutes is preferably 25 ppm or less. That is, according to this embodiment, since the curability of the composition (X) is improved, the proportion of the evolved gas generated from the cured product is preferably 25 ppm or less. In this case, it is not easy for the evolved gas to be generated from the cured product. Therefore, for example, it is not easy for voids caused by the evolved gas to be generated in a light-emitting device including an optical component formed of the cured product. Therefore, it is not easy for water and oxygen to reach the light-emitting element through the voids, and thus the light-emitting element is not easily deteriorated by water and oxygen. The proportion of the evolved gas is particularly preferably 15 ppm.

[0084] Such a reduction in the proportion of the evolved gas generated from the cured product of the composition (X) can be achieved by appropriately adjusting the composition of the radically polymerizable compound (A) within the range described above. It should be noted that the method for measuring the proportion of the evolved gas is described in detail in the Examples below.

[0085] The glass transition temperature of the cured product of the composition (X) is preferably 75°C or higher. That is, the composition (X) preferably has the property of becoming a cured product with a glass transition temperature of 75°C or higher upon curing. In this case, the cured product can have good heat resistance. Therefore, for example, when a treatment accompanied by a temperature rise is applied to the cured product, the cured product is not easily deteriorated. Therefore, for example, when an inorganic film (such as the passivation layer 6) overlapping with the optical component is formed by a vapor deposition method such as plasma CVD, even if the optical component is heated, the optical component is not easily deteriorated. In addition, by improving the heat resistance, the optical component can also be made suitable for applications such as in-vehicle use where strict requirements for heat resistance are imposed. The glass transition temperature of the cured product is more preferably 80°C or higher, further preferably 90°C or higher, and particularly preferably 100°C or higher. The glass transition temperature of this cured product can be achieved by appropriately adjusting the composition of the radically polymerizable compound (A) within the range described above.

[0086] An example of the structure of the light-emitting device 1 including an optical component made of the composition (X) will be described. The light-emitting device 1 includes a light source and an optical component that transmits the light emitted by the light source. For example, the light-emitting device 1 includes a light-emitting element 4, a sealing material 5 that covers the light-emitting element 4, and a passivation layer 6. In this case, the light-emitting element 4 is the light source, the sealing material 5 is the optical component, and the passivation layer 6 is the inorganic film. The sealing material 5 overlaps with the passivation layer 6.

[0087] The light-emitting element 4 includes, for example, a light-emitting diode. The light-emitting diode includes, for example, at least one of an organic EL element (organic light-emitting diode) and a micro light-emitting diode. When the light-emitting element 4 includes an organic light-emitting diode, the light-emitting device 1 including the light-emitting element 4 is, for example, an organic EL display. When the light-emitting element 4 includes a micro light-emitting diode, the light-emitting device 1 including the light-emitting element 4 is, for example, a micro LED display. It should be noted that EL is an abbreviation for electroluminescence.

[0088] Refer to Figure 1 An example of the structure of the light-emitting device 1 will be described. This light-emitting device 1 is a top-emitting type. The light-emitting device 1 includes a support substrate 2, a transparent substrate 3 that faces the support substrate 2 at an interval, a light-emitting element 4 located on the surface of the support substrate 2 facing the transparent substrate 3, and a passivation layer 6 and a sealing material 5 that cover the light-emitting element 4.

[0089] The support substrate 2 is made of, for example, a resin material, but is not limited thereto. The transparent substrate 3 is made of a material having translucency. The transparent substrate 3 is, for example, a glass substrate or a transparent resin substrate. The light-emitting element 4 includes, for example, a pair of electrodes 41 and 43 and an organic light-emitting layer 42 disposed between the electrodes 41 and 43. The organic light-emitting layer 42 includes, for example, a hole injection layer 421, a hole transport layer 422, an organic light-emitting layer 423, and an electron transport layer 424, and these layers are laminated in the above order.

[0090] The light-emitting device 1 includes a plurality of light-emitting elements 4, and the plurality of light-emitting elements 4 form an array 9 (hereinafter referred to as an element array 9) on the support substrate 2. The element array 9 further includes a partition wall 7. The partition wall 7 is disposed on the support substrate 2 and separates between two adjacent light-emitting elements 4. The partition wall 7 is made, for example, by forming a photosensitive resin material by photolithography. The element array 9 further includes a connection wiring 8 that electrically connects the electrodes 43 and the electron transport layers 424 of adjacent light-emitting elements 4 to each other. The connection wiring 8 is provided on the partition wall 7.

[0091] The passivation layer 6 corresponds to an inorganic film. The passivation layer 6 is preferably made of silicon nitride or silicon oxide, and particularly preferably made of silicon nitride. In Figure 1 the example shown, the passivation layer 6 includes a first passivation layer 61 and a second passivation layer 62. The first passivation layer 61 covers the element array 9 in a state of being in direct contact with the element array 9, and thus covers the light-emitting element 4. The second passivation layer 62 is disposed at a position on the opposite side of the element array 9 with respect to the first passivation layer 61, and there is a gap between the second passivation layer 62 and the first passivation layer 61. A sealing material 5 is filled between the first passivation layer 61 and the second passivation layer 62. That is, the first passivation layer 61 is interposed between the light-emitting element 4 and the sealing material 5 that covers the light-emitting element 4.

[0092] In addition, a second sealing material 52 is filled between the second passivation layer 62 and the transparent substrate 3. The second sealing material 52 is made of, for example, a transparent resin material. The material of the second sealing material 52 is not particularly limited. The material of the second sealing material 52 may be the same as or different from that of the sealing material 5.

[0093] A method for manufacturing the sealing material 5 using the composition (X) and a method for manufacturing the light-emitting device 1 will be described.

[0094] In the present embodiment, it is preferable to cure the composition (X) by irradiating ultraviolet rays after ejecting the composition (X) by an inkjet method and forming it into a film shape, thereby manufacturing the sealing material 5. In the present embodiment, the composition (X) can be ejected by an inkjet method and formed.

[0095] When ejecting the composition (X) by an inkjet method, when the composition (X) has a sufficiently low viscosity at normal temperature, for example, when the viscosity at 25 °C is 30 mPa·s or less, particularly 16 mPa·s or less, it can be formed by ejecting through the inkjet method without heating the composition (X). When the composition (X) is heated to reduce its viscosity, the composition (X) can be ejected by the inkjet method after heating the composition (X) to form. As described above, particularly when the viscosity of the composition (X) at 40 °C is 16 mPa·s or less, the composition (X) can be made to have a low viscosity by slightly heating, and the low-viscosity composition (X) can be ejected by the inkjet method. The heating temperature of the composition (X) is, for example, 20 °C or higher and 50 °C or lower.

[0096] More specifically, for example, first, a support substrate 2 is prepared. On one surface of the support substrate 2, for example, using a photosensitive resin material, the partition walls 7 are formed by photolithography. Next, a plurality of light-emitting elements 4 are provided on one surface of the support substrate 2. The light-emitting elements 4 can be formed by an appropriate method such as evaporation or coating. It is particularly preferable to form the light-emitting elements 4 by a coating method such as an inkjet method. Thus, the element array 9 is formed on the support substrate 2.

[0097] Next, a first passivation layer 61 is provided over the element array 9. The first passivation layer 61 can be formed, for example, by an evaporation method such as plasma CVD.

[0098] Next, over the first passivation layer 61, for example, the composition (X) is ejected by an inkjet method to form a coating film. If the inkjet method is applied both in the formation of the light-emitting elements 4 and the formation of the composition (X), the manufacturing efficiency of the light-emitting device 1 can be particularly improved. Next, the coating film of the composition (X) is irradiated with light to cure it, and the sealing material 5 is formed.

[0099] When irradiating the composition (X) with light, the composition (X) can be irradiated with light in an oxygen-containing atmosphere such as an air atmosphere, or the composition (X) can be irradiated with light in an inert atmosphere such as a nitrogen atmosphere.

[0100] Next, a second passivation layer 62 is provided over the sealing material 5. The second passivation layer 62 can be formed, for example, by an evaporation method such as plasma CVD.

[0101] Next, a photocurable resin material is provided on one surface of the support substrate 2 so as to cover the second passivation layer 62, and then a transparent substrate 3 is overlapped on the resin material. The transparent substrate 3 is, for example, a glass substrate or a transparent resin substrate.

[0102] Next, ultraviolet rays are irradiated onto the transparent substrate 3 from the outside. The ultraviolet rays pass through the transparent substrate 3 and reach the photocurable resin material. As a result, the photocurable resin material cures to produce the second sealing material 52.

[0103] In the present embodiment, as described above, the cured product of the composition (X) can have a high refractive index. Therefore, even when the sealing material 5 overlaps with the passivation layer 6 which is an inorganic film, a reduction in luminous efficiency is less likely to occur.

[0104] The thickness of the sealing material 5 is, for example, 1 μm or more and 50 μm or less. The thickness of the sealing material 5 is more preferably 20 μm or less, and further preferably 15 μm or less. In this case, by thinning the sealing material 5, the light-emitting device 1 can be thinned, and a light-emitting device 1 having flexibility, that is, capable of being bent, can also be obtained. In addition, in order to effectively suppress moisture from reaching the light-emitting element 4 by the sealing material 5, the thickness of the sealing material 5 is preferably 3 μm or more, more preferably 5 μm or more, and further preferably 8 μm or more.

[0105] The thickness of the passivation layer 6 overlapping with the sealing material 5 is, for example, 0.1 μm or more and 2 μm or less. As described above, in the case where the passivation layer 6 includes the first passivation layer 61 and the second passivation layer 62, the thicknesses of the first passivation layer 61 and the second passivation layer 62 are each preferably 0.1 μm or more and 2 μm or less.

[0106] It should be noted that the use of the composition (X) in the present embodiment is not limited to manufacturing the sealing material 5 for the light-emitting element 4. The composition (X) can be used to manufacture various optical components that transmit light emitted from a light source. For example, the optical component can be a color resist. That is, for example, a phosphor can be contained in the composition (X), and a color resist in a color filter can be produced from the composition (X). The color filter can be provided in, for example, a display device such as an organic EL display or a micro LED display which is a light-emitting device.

[0107] (Summary)

[0108] The photocurable resin composition of the first aspect contains a radically polymerizable compound (A), a photo radical polymerization initiator (B), and an inorganic filler (C). The radically polymerizable compound (A) contains: a first polyfunctional radically polymerizable compound (A1) having a structure in which an allyloxyalkyl group is bonded to the 2-position carbon of an acrylate; a monofunctional radically polymerizable compound (A2) having a nitrogen atom; and a second polyfunctional radically polymerizable compound (A3) different from the first polyfunctional radical polymerization. The proportion of the first polyfunctional radically polymerizable compound (A1) is 20% by mass or more and 98% by mass or less with respect to the radically polymerizable compound (A).

[0109] According to this method, the cured product of the photocurable resin composition has a high refractive index and can suppress breakage of the cured product during deformation.

[0110] In the second method, based on the first method, the first polyfunctional radically polymerizable compound (A1) contains methyl 2-(allyloxymethyl)acrylate represented by the following formula (1).

[0111] [Chemical formula 8]

[0112]

[0113] According to this method, breakage of the cured product during deformation can be further suppressed.

[0114] In the third method, based on the first or second method, the monofunctional radically polymerizable compound (A2) having a nitrogen atom contains at least one selected from a compound having an oxazoline ring, a compound having a morpholine ring, a compound having a dimethylamino group, a compound having a diethylamino group, and a compound having a pyrrolidone ring.

[0115] According to this method, breakage of the cured product during deformation can be further suppressed, particularly in a state where the cured product overlaps an inorganic film.

[0116] In the fourth method, based on any one of the first to third methods, the photo radical polymerization initiator (B) contains a compound (B1) that is excited by absorbing light with a wavelength of 395 nm.

[0117] According to this method, the photocurable resin composition can have particularly high ultraviolet curability, and thus generation of outgassing from the cured product can be suppressed.

[0118] In the fifth method, based on any one of the first to fourth methods, the proportion of the monofunctional radically polymerizable compound (A2) having a nitrogen atom is 1% by mass or more and 80% by mass or less relative to the radically polymerizable compound (A).

[0119] According to this method, breakage of the cured product during deformation can be further suppressed.

[0120] In the sixth method, based on any one of the first to fifth methods, the viscosity of the photocurable resin composition at 40 °C is 16 mPa·s or less.

[0121] According to this method, the photocurable resin composition has good formability, and it becomes easy to form by ejecting the photocurable resin composition by an inkjet method.

[0122] In the seventh mode, based on any one of the first to sixth modes, the refractive index of the cured product of the photocurable resin composition is 1.58 or more and 1.65 or less.

[0123] According to this mode, the photocurable resin composition can have a refractive index close to that of an inorganic film.

[0124] In the eighth mode, based on any one of the first to seventh modes, the inorganic filler (C) contains at least one of zirconia and titanium oxide.

[0125] According to this mode, the refractive index of the cured product can be further increased.

[0126] The optical component of the ninth mode includes the cured product of the photocurable resin composition of any one of the first to eighth modes.

[0127] According to this mode, the optical component has a high refractive index and can suppress breakage of the optical component during deformation.

[0128] The method for manufacturing the optical component of the tenth mode includes a step of forming the photocurable resin composition of any one of the first to eighth modes by an inkjet method and then irradiating the photocurable resin composition with light to cure it.

[0129] According to this mode, an optical component can be manufactured with good positional accuracy and the qualified rate is not likely to deteriorate.

[0130] The light-emitting device (1) of the eleventh mode includes a light source and an optical component that transmits the light emitted by the light source, and the optical component includes the cured product of the photocurable resin composition of any one of the first to eighth modes.

[0131] According to this mode, the optical component of the light-emitting device (1) has a high refractive index and can suppress breakage of the optical component during deformation.

[0132] The method for manufacturing the light-emitting device (1) of the twelfth mode is a method for manufacturing the light-emitting device (1) including a light source and an optical component that transmits the light emitted by the light source, and the method for manufacturing the light-emitting device includes a step of manufacturing the optical component by the method of the tenth mode.

[0133] According to this mode, the optical component in the light-emitting device (1) can be manufactured with good positional accuracy and the qualified rate is not likely to deteriorate.

[0134] Examples

[0135] 1. Preparation of the composition

[0136] The compositions of the examples and comparative examples were prepared by mixing the components shown in the following table. The details of the components shown in the table are as described below. In addition, in the column of "volume ratio of inorganic filler" in the table, the volume ratio of the inorganic filler to the total of the radically polymerizable compound, the photo-radical polymerization initiator, and the inorganic filler is shown, and in the column of "content of inorganic filler", the amount (parts by mass) of the inorganic filler relative to 100 parts by mass in total of the radically polymerizable compound and the photo-radical polymerization initiator is shown.

[0137] - First polyfunctional compound: Methyl 2-(allyloxymethyl)acrylate. Manufactured by Nippon Shokubai Co., Ltd. Product name AOMA.

[0138] - Nitrogen-containing monofunctional compound #1: Vinylmethyloxazolidinone. Manufactured by BASF.

[0139] - Nitrogen-containing monofunctional compound #2: Acryloylmorpholine. Manufactured by KJ Chemicals Co., Ltd.

[0140] - Nitrogen-containing monofunctional compound #3: Dimethylacrylamide. Manufactured by KJ Chemicals Co., Ltd.

[0141] - Second polyfunctional compound: Glycerol triacrylate. Manufactured by Toagosei Co., Ltd. Product name M-930.

[0142] - Aromatic ring-containing monofunctional compound #1: The compound shown by the following chemical formula (32). Manufactured by Kyoeisha Chemical Co., Ltd. Product name Light Acrylate OPP

[0143] [Chemical formula 9]

[0144]

[0145] - Aromatic ring-containing monofunctional compound #2: The compound shown by the following chemical formula (33). Manufactured by Shin-Nakamura Chemical Co., Ltd. Product name A-BPML.

[0146] [Chemical formula 10]

[0147]

[0148] - Aromatic ring-containing monofunctional compound #3: The compound shown by the following chemical formula (21). Manufactured by Kyoeisha Chemical Co., Ltd. Product name NMT-A.

[0149] [Chemical formula 11]

[0150]

[0151] - Initiator: 2,4,6-trimethylbenzoyl-diphenylphosphine oxide. Manufactured by IGM RESINS B.V., product name Omnirad TPO H.

[0152] - Inorganic filler #1: Zirconia. Manufactured by Sakai Chemical Industry Co., Ltd., product name SZR-CW. Average particle size 6 nm, specific gravity 5.6.

[0153] - Inorganic filler #2: Titanium oxide. Manufactured by TAYCA Corporation, product name MT-05. Average particle size 10 nm, specific gravity 4.

[0154] - Silane coupling agent #1: Manufactured by Shin-Etsu Chemical Co., Ltd., product name KBM-5103.

[0155] - Silane coupling agent #2: Manufactured by Shin-Etsu Chemical Co., Ltd., product name X-12-1333A.

[0156] 2. Evaluation tests

[0157] (1) Refractive index

[0158] A coating film with a thickness of 300 μm was made from the coating composition. In a nitrogen atmosphere, a UV irradiator (manufactured by USHIO Inc., model Unijet E075IIHD) was used to irradiate the coating film with light having a peak wavelength of 395 nm under the conditions of an irradiation intensity of 0.5 W / cm 2 and an accumulated light quantity of 1.5 J / cm 2 . Thus, a test sample was made. The refractive index of the light with a wavelength of 589 nm of this sample was measured at 25 °C in an atmosphere using a multi-wavelength Abbe refractometer (manufactured by ATAGO, model DR-M2).

[0159] (2) Viscosity at 25 °C

[0160] Using a rheometer (manufactured by Anton Paar Japan, model DHR-2), the viscosity of the composition was measured under the conditions of a temperature of 25 °C and a shear rate of 1000 s -1 .

[0161] (3) Viscosity at 40 °C

[0162] Using a rheometer (manufactured by Anton Paar Japan, model DHR-2), the viscosity of the composition was measured under the conditions of a temperature of 40 °C and a shear rate of 1000 s -1 .

[0163] (4) Inkjet performance

[0164] The composition was added to the ink cartridge of an inkjet printer (manufactured by Fujifilm, model DMP2831), and droplets of the composition were ejected from the nozzles of the inkjet printer under the conditions of a temperature of 40 °C and a frequency of 1 kHz. The droplets were observed with a high-speed camera. As a result, the case where the droplets did not separate was evaluated as "A", the case where the satellite droplets (Japanese: サテライト) separated from the original droplets and then the satellite droplets and the original droplets merged again to become one droplet was evaluated as "B", and the case where the satellite droplets remained separated from the original droplets without merging was evaluated as "C".

[0165] (5)Curability

[0166] The composition was measured with an infrared spectroscopic analyzer (manufactured by Agilent Technology, model Agilent Cary 610FTIR microscope system), and an IR spectrum was thus obtained.

[0167] The composition was coated to form a coating film with a thickness of 10 μm. Under a nitrogen atmosphere, the coating film was irradiated with a UV irradiator (manufactured by USHIO, model Unijet E075IIHD) at an irradiation intensity of 0.5 W / cm 2 and a cumulative light amount of 1.5 J / cm 2 with light having a peak wavelength of 395 nm. Then, the composition (cured product) after ultraviolet irradiation was measured with the above-mentioned infrared spectroscopic analyzer, and an IR spectrum was thus obtained.

[0168] In each of the two IR spectra, the absorption peak intensity of the acryloyl group appearing at 810 cm -1 was measured. Based on the peak intensity I0 of the coating film and the peak intensity I1 of the cured product, the reduction rate of the reactive functional groups in the composition before and after ultraviolet irradiation was calculated using the formula {1 - (I0 - I1) / I0} × 100 (%). The result was used as the reaction rate. The case where the reaction rate was 90% or more was evaluated as "A", the case where it was 80% or more and less than 90% was evaluated as "B", and the case where it was less than 80% was evaluated as "C".

[0169] (6)Evaluation of evolved gas

[0170] The evolved gas during heating of the cured product of the composition was sampled by the headspace method and measured with a gas chromatograph. Specifically, first, 100 mg of the composition was placed in a vial with a headspace volume of 22 mL. Then, under a nitrogen atmosphere, the composition was irradiated with a UV irradiator (manufactured by USHIO, model Unijet E075IIHD) at an irradiation intensity of 0.5 W / cm 2 and a cumulative light amount of 1.5 J / cm 2Irradiate light with a peak wavelength of 395 nm under the given conditions, and after curing the composition, seal the vial. Then, after heating the composition at 110 °C for 30 minutes, introduce the gas phase part in the vial into a gas chromatograph for analysis. As a result, based on the peak area of the obtained gas chromatogram, determine the concentration of the evolved gas generated by the composition. The concentration of the evolved gas refers to the volume fraction of the evolved gas in the gas phase of the vial relative to the volume of the vial (22 mL).

[0171] It should be noted that the concentration of the evolved gas is determined using toluene as a reference substance. Specifically, volatilize toluene in the vial to prepare two reference samples with toluene concentrations of 1000 ppm and 100 ppm. Introduce each reference sample into the gas chromatograph for analysis. Based on the peak areas of the two chromatograms obtained therefrom, stipulate the relationship between the peak area and the concentration, and based on this result, determine the concentration of the above-mentioned evolved gas.

[0172] (7)Sealability

[0173] Form a silicon oxynitride film (SiON film) as an inorganic film with a thickness of 1 μm on a glass slide by CVD method. Coat the composition with a thickness of 10 μm on the inorganic film to form a coating film. Under a nitrogen atmosphere, use a UV irradiator (manufactured by USHIO, model Unijet E075IIHD) to irradiate the coating film with light having a peak wavelength of 395 nm under the conditions of an irradiation intensity of 0.5 W / cm 2 and an accumulated light amount of 1.5 J / cm 2 Stretch the coating film in the 90-degree direction using an Autograph (manufactured by Shimadzu Corporation, model AGS-X) and measure the peel strength. Evaluate the case where the peel strength is 100 mN / cm or more as "A", the case where the peel strength is 50 mN / cm or more as "B", the case where the peel strength is 20 mN / cm or more as "C", and the case where the peel strength is less than 20 mN / cm as "D".

[0174] (8)Flexibility

[0175] By CVD method, form a silicon oxynitride film (SiON film) as an inorganic film with a thickness of 1 μm on a polyimide film as a substrate. Coat the composition with a thickness of 10 μm on the inorganic film to form a coating film. Under a nitrogen atmosphere, use a UV irradiator (manufactured by USHIO, model Unijet E075IIHD) to irradiate the coating film with light having a peak wavelength of 395 nm under the conditions of an irradiation intensity of 0.5 W / cm 2 and an accumulated light amount of 1.5 J / cm 2 to produce a film with a thickness of 10 μm. Thus, an evaluation sample having a substrate, an inorganic film, and a film was produced.

[0176] The test sample for evaluation was subjected to a test of repeated bending 100,000 times under the conditions where the radius of curvature of the bent portion was 1.5 mm, 2.0 mm, and 3.0 mm, respectively.

[0177] The minimum bending radius at which no peeling or cracking occurred in the film of the test sample for evaluation after the test is shown in the table. It should be noted that in Comparative Examples 1 and 2, peeling or cracking occurred even when the bending radius was 3.0 mm.

[0178] (9) Glass transition temperature

[0179] A coating composition was applied to form a coating film. In an atmospheric atmosphere, a UV irradiator (manufactured by USHIO Inc., model E075IIHD) was used to irradiate the coating film with light having a peak wavelength of 395 nm at an irradiation intensity of 3 W / cm 2 and an accumulated light amount of 15 J / cm 2 to photocure the coating film and produce a film with a thickness of 500 μm. A viscoelasticity measuring device (manufactured by Hitachi High-Tech Science Corporation, model DMA7100) was used to measure the glass transition temperature of a sample cut from the film.

[0180]

[0181]

[0182]

[0183] Explanation of reference numerals

[0184] 1 Light-emitting device

[0185] 4 Light-emitting element (light source)

[0186] 5 Sealing material (optical component)

Claims

1. A photocurable resin composition containing a radically polymerizable compound (A), a photo-radical polymerization initiator (B), and an inorganic filler (C). The radically polymerizable compound (A) contains: A first polyfunctional radically polymerizable compound (A1) having a structure in which an allyloxyalkyl group is bonded to the 2-position carbon of acrylate; A monofunctional radically polymerizable compound (A2) having a nitrogen atom; and A second polyfunctional radically polymerizable compound (A3) different from the first polyfunctional radically polymerizable compound (A1). The proportion of the first polyfunctional radically polymerizable compound (A1) is 20% by mass or more and 98% by mass or less with respect to the radically polymerizable compound (A).

2. The photocurable resin composition according to claim 1, wherein, The first polyfunctional radically polymerizable compound (A1) contains methyl 2-(allyloxymethyl)acrylate represented by the following formula (1). 。 3. The photocurable resin composition according to claim 1, wherein, The monofunctional radically polymerizable compound (A2) having a nitrogen atom contains at least one selected from a compound having an oxazoline ring, a compound having a morpholine ring, a compound having a dimethylamino group, a compound having a diethylamino group, and a compound having a pyrrolidone ring.

4. The photocurable resin composition according to claim 1, wherein, The photo-radical polymerization initiator (B) contains a compound (B1) that absorbs light with a wavelength of 395 nm.

5. The photocurable resin composition according to claim 1, wherein, The amount of the monofunctional radically polymerizable compound (A2) having a nitrogen atom is 1% by mass or more and 80% by mass or less with respect to the radically polymerizable compound (A).

6. The photocurable resin composition according to claim 1, wherein, The viscosity of the photocurable resin composition at 40 °C is 16 mPa·s or less.

7. The photocurable resin composition according to claim 1, wherein, The refractive index of the cured product of the photocurable resin composition is 1.58 or more and 1.65 or less.

8. The photocurable resin composition according to claim 1, wherein, The inorganic filler (C) contains at least one of zirconia and titania.

9. An optical component comprising a cured product of the photocurable resin composition according to any one of claims 1 to 8.

10. A method for manufacturing an optical component, comprising the steps of forming the photocurable resin composition according to any one of claims 1 to 8 by an inkjet method and then irradiating the photocurable resin composition with light to cure it.

11. A light-emitting device comprising a light source and an optical component that transmits the light emitted by the light source, the optical component comprising a cured product of the photocurable resin composition according to any one of claims 1 to 8.

12. A method for manufacturing a light-emitting device, which is a method for manufacturing a light-emitting device comprising a light source and an optical component that transmits the light emitted by the light source. The method for manufacturing the light-emitting device includes the step of manufacturing the optical component by the method according to claim 10.

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