Ultraviolet-curable resin composition, optical component, method for manufacturing optical component, light-emitting device, and method for manufacturing light-emitting device

Abstract

To provide a UV-curable resin composition that is easy to be cured efficiently in the atmosphere, and hardly causes a deterioration of a light source even when applied to make an optical component in a light emitting device.SOLUTION: A UV-curable resin composition has a photopolymerizable compound (A) and a photopolymerization initiator (B). The proportion of dissolved oxygen in the UV-curable resin composition is 100 mg / L or less relative to the UV-curable resin composition. The UV-curable resin composition has ultraviolet curability in the atmosphere.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to an ultraviolet-curable 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, and more particularly to an ultraviolet-curable resin composition that can be molded by an inkjet method, an optical component made from the ultraviolet-curable resin composition, a method for manufacturing an optical component using the ultraviolet-curable resin composition, a light-emitting device including the optical component, and a method for manufacturing a light-emitting device using the ultraviolet-curable resin composition. [Background technology]

[0002] Light-emitting devices such as organic electroluminescence (EL) light-emitting devices are used in lighting, displays, and other applications, and are expected to become more widespread in the future.

[0003] A light emitting device is configured by, for example, disposing a light emitting element on a support substrate and disposing a transparent substrate opposite the support substrate, in which case light emitted by the light emitting element passes through the transparent substrate and is emitted to the outside.

[0004] When light-emitting elements such as organic EL elements are deteriorated by moisture, dark spots, which are areas that do not emit light, may appear. For this reason, the light-emitting elements are covered with a transparent sealing material and a passivation layer made of a nitrogen compound to prevent moisture from entering the light-emitting elements from the outside (see Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-186850 Summary of the Invention [Problem to be solved by the invention]

[0006] According to the inventor's research, even if the intrusion of moisture into a light source such as a light-emitting element is sufficiently suppressed, the light source may deteriorate. Also, it may be difficult to cure a composition for producing an encapsulant in the air.

[0007] An object of the present invention is to provide an ultraviolet-curable resin composition that can be easily cured efficiently in an atmospheric environment and that is unlikely to cause deterioration of the light source when used to produce optical components in a light-emitting device; optical components produced from the ultraviolet-curable resin composition; a method for producing optical components using the ultraviolet-curable resin composition; a light-emitting device including the optical components; and a method for producing a light-emitting device using the ultraviolet-curable resin composition. [Means for solving the problem]

[0008] An ultraviolet-curable resin composition according to one embodiment of the present invention contains a photopolymerizable compound (A) and a photopolymerization initiator (B). The proportion of dissolved oxygen in the ultraviolet-curable resin composition is 100 mg / L or less relative to the ultraviolet-curable resin composition. The ultraviolet-curable resin composition has ultraviolet curability in an atmospheric environment. An optical component according to one aspect of the present invention includes a cured product of the ultraviolet-curable resin composition.

[0009] A method for manufacturing an optical component according to one aspect of the present invention includes molding the ultraviolet-curable resin composition by an inkjet method, and then curing the ultraviolet-curable resin composition by irradiating it with ultraviolet light.

[0010] A light emitting device according to one aspect of the present invention includes a light source and an optical component that transmits light emitted from the light source, the optical component including a cured product of the ultraviolet-curable resin composition.

[0011] A method for manufacturing a light-emitting device according to one aspect of the present invention is a method for manufacturing a light-emitting device including a light source and an optical component that transmits light emitted by the light source, the method including manufacturing the optical component by the method for manufacturing an optical component. [Effects of the Invention]

[0012] According to one aspect of the present invention, there are provided an ultraviolet-curable resin composition that can be efficiently cured in an atmospheric environment and that is unlikely to cause deterioration of a light source when used to produce optical components in a light-emitting device; a method for producing the ultraviolet-curable resin composition; optical components produced from the ultraviolet-curable resin composition; a method for producing optical components using the ultraviolet-curable resin composition; a light-emitting device including the optical components; and a method for producing a light-emitting device using the ultraviolet-curable resin composition. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a schematic cross-sectional view showing a first example of a light emitting device according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0014] An embodiment of the present invention will be described below.

[0015] The ultraviolet-curable resin composition according to this embodiment (hereinafter also referred to as composition (X)) contains a photopolymerizable compound (A) and a photopolymerization initiator (B). The proportion of dissolved oxygen in composition (X) is 100 mg / L or less relative to composition (X). Composition (X) is ultraviolet-curable in the air.

[0016] According to this embodiment, composition (X) can be efficiently cured in an air atmosphere. Furthermore, in this embodiment, the proportion of dissolved oxygen in composition (X) is 100 mg / L or less relative to composition (X). Therefore, when an optical component is produced from composition (X), oxygen from the optical component is unlikely to reach the light source in a light-emitting device equipped with the optical component. Therefore, even when composition (X) is used to produce an optical component in a light-emitting device, deterioration of the light source due to oxygen is unlikely to occur. Furthermore, since the proportion of dissolved oxygen is 100 mg / L or less, oxygen inhibition is unlikely to occur when photocuring composition (X). Therefore, composition (X) can be easily cured, and it is easy to realize that composition (X) has UV curability in an air atmosphere.

[0017] Here, being UV-curable in the atmosphere means that the pencil hardness of the cured product obtained by curing composition (X) in the atmosphere is 4B or more, preferably 2B or more. The test conditions for confirming UV-curability in the atmosphere will be explained in detail in the Examples section below.

[0018] As described above, optical components can be produced from composition (X), and light-emitting devices equipped with optical components can also be produced. Note that the use of composition (X) is not limited to the production of optical components, and composition (X) can be used in a variety of applications that utilize the properties of composition (X).

[0019] The dissolved oxygen ratio is preferably 70 mg / L or less, and more preferably 50 mg / L. The lower the dissolved oxygen ratio, the better, and ideally 0 mg / L. The dissolved oxygen ratio is substantially 5 mg / L or more, and it is very difficult to reduce the dissolved oxygen ratio below this. The dissolved oxygen ratio is measured in accordance with JIS K0102. Specific measurement methods will be explained in detail in the Examples section below.

[0020] The composition (X) is preferably molded by an inkjet method. In this case, a cured product of the composition (X) can be easily produced with high positional accuracy. Furthermore, compared with molding by a printing method involving contact, such as a screen printing method, when the composition (X) is molded by the inkjet method, foreign matter is less likely to be mixed into the composition (X) and its cured product, and therefore the yield when manufacturing optical components is less likely to decrease.

[0021] The viscosity of composition (X) at 25°C is preferably 30 mPa·s or less. In this case, composition (X) can be easily molded at room temperature, particularly by an inkjet method. This viscosity is more preferably 25 mPa·s or less, even more preferably 20 mPa·s or less, and particularly preferably 15 mPa·s or less. This viscosity is also preferably 1 mPa·s or more, and even more preferably 5 mPa·s or more.

[0022] It is also preferable that the viscosity of composition (X) at 40°C is 30 mPa·s or less. In this case, regardless of the viscosity of composition (X) at room temperature, it is possible to lower the viscosity by slightly heating composition (X). Therefore, heating composition (X) makes it easier to mold, particularly by inkjet molding. Furthermore, because the viscosity of composition (X) can be lowered without significantly heating it, changes in the composition of composition (X) due to volatilization of the components in composition (X) can be made less likely. This viscosity is more preferably 25 mPa·s or less, even more preferably 20 mPa·s or less, and particularly preferably 15 mPa·s or less. It is also preferable that this viscosity is 1 mPa·s or more, and even more preferably 5 mPa·s or more.

[0023] Such a low viscosity of composition (X) at 25° C. or 40° C. can be achieved by the composition of composition (X) described in detail below. The method and conditions for measuring the viscosity of composition (X) at 25° C. and 40° C. will be described in detail in the Examples section below.

[0024] In this embodiment, molding defects are unlikely to occur when composition (X) is produced by the inkjet method. This is presumably because the dissolved oxygen content of composition (X) is 100 mg / L or less, which makes it difficult for bubbles to form within droplets of composition (X) ejected by the inkjet method, and therefore makes it difficult for defective droplets such as satellites and mist to form. Note that satellites are droplets that separate from the original droplets when droplets are ejected by the inkjet method. Mist is multiple small droplets that separate from the original droplets. Satellites and mist tend to adhere to positions on the target object that are different from the original droplets, which can easily deteriorate the dimensional accuracy of the cured product produced from composition (X).

[0025] It is preferable that the outgassing rate when a cured product of composition (X) is heated at 80°C for 30 minutes is 500 ppm or less. In this case, outgassing from the cured product is less likely to occur. This makes it less likely that voids due to outgassing will occur in, for example, a light-emitting device equipped with an optical component made of the cured product. This makes it less likely that water and oxygen will reach the light-emitting element through voids, making it less likely that the light-emitting element will deteriorate due to water and oxygen. The method and conditions for measuring the outgassing rate will be explained in detail in the Examples section below.

[0026] Furthermore, when a test is conducted in which composition (X) is left to stand in a nitrogen atmosphere at a temperature of 60°C for two months, the viscosity change rate Rμ calculated by the following formula (M1) from the viscosity μ0 of composition (X) before the test and the viscosity μ1 of composition (X) after the test is preferably less than 20%. Rμ={(μ1-μ0) / μ0}×100(%) …(M1) In this case, composition (X) can have particularly good storage stability. It is more preferable that this viscosity change rate Rμ is 10% or less. The lower the viscosity change rate Rμ, the better, and ideally it is 0%.

[0027] Preferably, composition (X) contains no solvent or contains 1% by mass or less of solvent. In this case, outgassing from composition (X) and the cured product of composition (X) is unlikely to occur. Furthermore, a drying step for removing the solvent from composition (X) and the cured product can be eliminated during the production of optical components and light-emitting devices. A drying step for removing the solvent from at least one of composition (X) and the cured product may be performed. This allows for at least one of a lower heating temperature and a shorter heating time in the drying step. Therefore, outgassing from the optical components can be reduced without reducing the production efficiency of optical components and light-emitting devices. Furthermore, when composition (X) is molded, particularly by an inkjet method, the thickness of the molded composition (X) is unlikely to decrease due to solvent evaporation, and therefore the thickness of the optical components is unlikely to decrease. Therefore, the thickness of the optical components can be maximized even when molded by the inkjet method. The solvent content is more preferably 0.5% by mass or less, even more preferably 0.3% by mass or less, and particularly preferably 0.1% by mass or less. It is particularly preferred that the composition (X) does not contain a solvent or contains only an unavoidably mixed solvent.

[0028] The glass transition temperature of the cured product of composition (X) is preferably 80°C or higher. In other words, composition (X) preferably has the property of curing to form a cured product with a glass transition temperature of 80°C or higher. In this case, the cured product can have good heat resistance. Therefore, for example, when the cured product is subjected to a process that increases the temperature, the cured product is less likely to deteriorate. Therefore, for example, when an inorganic material layer (e.g., passivation layer 6) that overlies an optical component is produced by a vapor deposition method such as plasma CVD, the optical component is less likely to deteriorate even when heated. Furthermore, by improving heat resistance, the optical component can be adapted for automotive applications that require strict heat resistance. The glass transition temperature of the cured product is more preferably 90°C or higher, and even more preferably 100°C or higher. This glass transition temperature of the cured product can be achieved by the composition of composition (X), which will be described in detail below.

[0029] When 20 mg of composition (X) is heated at 100°C for 30 minutes using a thermogravimetric analyzer, the volatility is preferably 40% or less. The volatility of composition (X) is defined as the percentage of the weight loss of composition (X) after treatment (the difference between the weight of composition (X) before and after treatment) relative to the weight of composition (X) before treatment. In this case, the low volatility of composition (X) enhances the storage stability of composition (X). Furthermore, outgassing is less likely to occur from cured compositions of composition (X) and optical components. Therefore, voids due to outgassing are even less likely to occur within light-emitting devices. The volatility of composition (X) can be determined by heating 20 mg of composition (X) at 100°C for 30 minutes using a thermogravimetric analyzer and calculating the weight loss after treatment relative to the weight before treatment. When 20 mg of composition (X) is heated at 100°C for 30 minutes using a thermogravimetric analyzer, the volatility is preferably 30% or less, and even more preferably 20% or less. The lower limit of the volatility of composition (X) is not particularly limited, but may be, for example, 0.1% or more.

[0030] The components contained in composition (X) will be explained in more detail below.

[0031] The photopolymerizable compound (A) is a component that can undergo a polymerization reaction upon irradiation with ultraviolet light in the presence or absence of a photopolymerization initiator (B). The photopolymerization initiator (B) may contain a curing catalyst. The photopolymerizable compound (A) contains, for example, at least one component selected from the group consisting of a monomer, an oligomer, and a prepolymer.

[0032] The photopolymerizable compound (A) contains, for example, at least one of a radically polymerizable compound (A1) and a cationically polymerizable compound (W). When the photopolymerizable compound (A) contains the radically polymerizable compound (A1), the composition (X) preferably further contains a photoradical polymerization initiator (B1) as the photopolymerization initiator (B). When the photopolymerizable compound (A) contains a cationically polymerizable compound (W), the composition (X) preferably further contains a photocationic polymerization initiator (B2) (cationic curing catalyst) as the photopolymerization initiator (B).

[0033] The case where the photopolymerizable compound (A) contains a radically polymerizable compound (A1) will be described. In an oxygen-containing atmosphere such as the air atmosphere, the curing reaction of the radically polymerizable compound (A1) is inhibited by oxygen inhibition, and the reaction efficiency is likely to decrease. However, in this embodiment, the proportion of dissolved oxygen in the composition (X) is 100 mg / L or less, so oxygen inhibition is suppressed. Therefore, even if the photopolymerizable compound (A) contains the radically polymerizable compound (A1), the curing of the composition (X) is unlikely to be inhibited by oxygen in an oxygen-containing atmosphere such as the air atmosphere.

[0034] The radically polymerizable compound (A1) preferably contains an acrylic compound (Y), which has one or more (meth)acryloyl groups in one molecule.

[0035] The viscosity of the entire acrylic compound (Y) at 25°C is preferably 50 mPa·s or less. In this case, the acrylic compound (Y) can particularly reduce the viscosity of the composition (X). The viscosity of the entire acrylic compound (Y) is more preferably 30 mPa·s or less, and particularly preferably 20 mPa·s or less. The viscosity of the entire acrylic compound (Y) is, for example, 3 mPa·s or more.

[0036] It is also preferable that the viscosity of the entire acrylic compound (Y) at 40°C is 50 mPa·s or less. In this case, the acrylic compound (Y) can particularly reduce the viscosity of the composition (X) when heated. The viscosity of the entire acrylic compound (Y) is more preferably 30 mPa·s or less, and particularly preferably 20 mPa·s or less. Furthermore, the viscosity of the entire acrylic compound (Y) is, for example, 3 mPa·s or more.

[0037] The percentage of components in the acrylic compound (Y) having a boiling point of 270°C or higher is preferably 80% by mass or higher. In this case, the storage stability of the composition (X) is particularly unlikely to be impaired, and outgassing from the cured product is particularly unlikely to occur. It is even more preferable that the percentage of components in the acrylic compound (Y) having a boiling point of 280°C or higher is 80% by mass or higher.

[0038] The acrylic compound (Y) preferably contains a component having a viscosity of 20 mPa·s or less at 25° C. In this case, the viscosity of the composition (X) can be reduced.

[0039] The proportion of the component having a viscosity of 20 mPa·s or less at 25°C relative to the total amount of acrylic compound (Y) is preferably 50% by mass or more and 100% by mass or less. In this case, the viscosity of composition (X) can be particularly reduced, making composition (X) particularly easy to apply by inkjet method. This proportion is more preferably 60% by mass or more, and even more preferably 70% by mass or more. Furthermore, this proportion is more preferably 95% by mass or less, and even more preferably 90% by mass or less.

[0040] The component having a viscosity of 20 mPa·s or less at 25°C preferably contains a compound having a glass transition temperature of 80°C or higher. In this case, the viscosity of composition (X) can be reduced while the glass transition temperature of the cured product can be increased. This component preferably contains a compound having a glass transition temperature of 90°C or higher, and even more preferably contains a compound having a glass transition temperature of 100°C or higher. There is no upper limit to the glass transition temperature of the compound contained in this component, but it is, for example, 150°C or lower.

[0041] The compounds that the acrylic compound (Y) may contain will be described below.

[0042] The acrylic compound (Y) preferably contains a polyfunctional acrylic compound (Y1) having two or more radically polymerizable functional groups, including a (meth)acryloyl group, in one molecule. In this case, the polyfunctional acrylic compound (Y1) can increase the glass transition temperature of the cured product, thereby improving the heat resistance of the cured product. The proportion of the polyfunctional acrylic compound (Y1) is preferably 50% by mass or more and 100% by mass or less based on the total amount of the acrylic compound (Y). The acrylic compound (Y) may contain only the polyfunctional acrylic compound (Y1).

[0043] Examples of the polyfunctional acrylic compound (Y1) include 1,3-butylene glycol 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 polyethoxydiacrylate, bisphenol F polyethoxydiacrylate, pentatriestol tetraacrylate, propoxylated (2) neopentyl glycol diacrylate, trimethylolpropane triacrylate, tris(2-hydroxyethyl) isocyanurate triacrylate, pentaerythritol triacrylate, and ethoxylated (3) trimethylol Propane triacrylate, propoxylated (3) glyceryl triacrylate, pentaerythritol tetraacrylate, ditrimethylolpropane tetraacrylate, ethoxylated (4) pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, 2-(2-ethoxyethoxy)ethyl acrylate, hexadiol diacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, tripropylene glycol triacrylate, bispentaerythritol 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 phosphoric acid triacrylate, ethoxylated tripropylene glycol diacrylate, neopentyl glycol modified trimethylolpropane diacrylate, stearic acid modified pentaerythritol diacrylate, tetramethylolpropane triacrylate, tetramethylolmethane triacrylate, caprolactone modified trimethylolpropane triacrylate, propoxylated glyceryl triacrylate, tetramethylolmethane tetraacrylate, ethoxylated pentaerythritol tetraacrylate, dipentaerythritol It contains at least one compound selected from the group consisting of erythritol 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.

[0044] The polyfunctional acrylic compound (Y1) preferably has an acrylic equivalent of 150 g / eq or less, more preferably 90 g / eq or more and 150 g / eq or less. The polyfunctional acrylic compound (Y1) has a weight average molecular weight of, for example, 100 or more and 1,000 or less, more preferably 200 or more and 800 or less.

[0045] The polyfunctional acrylic compound (Y1) preferably contains a compound (Y11) having a structure represented by the following formula (200).

[0046] CH2=CR 1 -COO-(R 3 -O)n-CO-CR2 =CH2 …(200) In formula (200), R 1 and R 2 Each of the groups is hydrogen or a methyl group, n is an integer of 1 or more, R 3 is an alkylene group having one or more carbon atoms, and when n is 2 or more, there are multiple R 3 may be the same or different from each other.

[0047] The compound (Y11) has a structure shown in formula (200), and in particular, R 3 Since the carbon number of R is 3 or more, the affinity of the cured product with water is not easily increased. Therefore, the phosphor (C) is not easily deteriorated by water. 3 The number of carbon atoms in the formula (Y11) is, for example, 1 or more and 15 or less, preferably 3 or more and 15 or less. Furthermore, compound (Y11) has the structure shown in formula (200), and in particular, has two (meth)acryloyl groups in one molecule, thereby increasing the glass transition temperature of the cured product and thereby improving the heat resistance of the cured product. Furthermore, n in formula (200) is, for example, an integer of 1 or more and 12 or less.

[0048] The percentage of the compound (Y11) relative to the acrylic compound (Y) is preferably 50% by mass or more. In this case, the affinity of the cured product for water is particularly difficult to increase. The percentage of the compound (Y11) relative to the acrylic compound (Y) is, for example, 100% by mass or less, or 95% by mass or less, and preferably 80% by mass or less.

[0049] The compound (Y11) preferably contains a component having a boiling point of 270°C or higher. That is, the acrylic compound (Y) preferably contains a component having a structure represented by formula (200) and a boiling point of 270°C or higher. In this case, the acrylic compound (Y) is less likely to volatilize from the composition (X) during storage or when the composition (X) is heated. Therefore, the storage stability of the composition (X) is less likely to be impaired. Furthermore, even if the compound (Y11) remains unreacted in the cured product of the composition (X), outgassing due to the compound (Y11) is less likely to occur from the cured product. Therefore, voids due to outgassing are less likely to occur in the light-emitting device 1. If voids exist in the light-emitting device 1, moisture may penetrate into the light-emitting element 4 through the voids. However, if voids are less likely to occur, moisture is less likely to penetrate into the light-emitting element 4. The boiling point is the boiling point under normal pressure obtained by converting the boiling point under reduced pressure, and is determined by the method described in, for example, Science of Petroleum, Vol. II, p. 1281 (1938). It is more preferable that compound (Y11) contains a component having a boiling point of 280°C or higher.

[0050] The percentage of the compound (Y11) relative to the acrylic compound (Y) is preferably 50% by mass or more. In this case, the storage stability of the composition (X) is effectively improved, outgassing from the cured product is effectively reduced, and the affinity of the cured product for water is particularly improved. The percentage of the compound (Y11) relative to the acrylic compound (Y) is, for example, 100% by mass or less, or 95% by mass or less, and preferably 80% by mass or less.

[0051] The viscosity of compound (Y11) at 25°C is preferably 25 mPa·s or less. In this case, compound (Y11) can reduce the viscosity of composition (X). The viscosity of compound (Y11) at 25°C is more preferably 25 mPa·s or less, even more preferably 20 mPa·s or less, and particularly preferably 15 mPa·s or less. The viscosity of compound (Y11) at 25°C is, for example, 1 mPa·s or more, preferably 3 mPa·s or more, and more preferably 5 mPa·s or more.

[0052] The compound (Y11) contains, for example, at least one compound selected from the group consisting of alkylene glycol di(meth)acrylate, polyalkylene glycol di(meth)acrylate, and alkylene oxide-modified alkylene glycol di(meth)acrylate.

[0053] Alkylene glycol di(meth)acrylate is a compound of formula (200) where n is 1. In this case, R 3 The number of carbon atoms in R is preferably 4 to 12. 3It may be linear or branched. In particular, it is preferable that the alkylene glycol di(meth)acrylate contains at least one compound selected from the group consisting of 1,4-butanediol diacrylate, 1,3-butylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, 1,9-nonanediol diacrylate, 1,10-decanediol diacrylate, 1,4-butanediol dimethacrylate, 1,3-butylene glycol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, 1,10-decanediol dimethacrylate, and 1,12-dodecanediol dimethacrylate. In addition, alkylene glycol di(meth)acrylates include Sartomer product number SR213, Osaka Organic Chemical Industry Co., Ltd. product number V195, Sartomer product number SR212, Sartomer product number SR247, Kyoei Chemical Industry Co., Ltd. product name Light Acrylate NP-A, Sartomer product number SR238NS, Osaka Organic Chemical Industry Co., Ltd. product number V230, Daicel Corporation product number HDDA, Kyoei Chemical Industry Co., Ltd. product number 1,6HX-A, Osaka Organic Chemical Industry Co., Ltd. product number V260, Kyoei Chemical Industry Co., Ltd. product number 1,9-ND-A, Shin-Nakamura Chemical Co., Ltd. product number A-NOD-A, Sartomer product number CD595, Sartomer product number S It is preferable that the composition contains at least one compound selected from the group consisting of R214NS, Shin-Nakamura Chemical Co., Ltd. product number BD, Sartomer Co., Ltd. product number SR297, Sartomer Co., Ltd. product number SR248, Kyoei Chemical Co., Ltd. product name Light Ester NP, Sartomer Co., Ltd. product number SR239NS, Kyoei Chemical Co., Ltd. product name Light Ester 1,6HX, Shin-Nakamura Chemical Co., Ltd. product number HD-N, Kyoei Chemical Co., Ltd. product name Light Ester 1,9ND, Shin-Nakamura Chemical Co., Ltd. product number NOD-N, Kyoei Chemical Co., Ltd. product name Light Ester 1,10DC, Shin-Nakamura Chemical Co., Ltd. product number DOD-N, and Sartomer Co., Ltd. product number SR262.

[0054] Polyalkylene glycol di(meth)acrylate is, for example, a compound represented by formula (200) in which n is 2 or greater. n is, for example, 2 to 10, preferably 2 to 7, also preferably 2 to 6, and also preferably 2 to 3. R 3 The number of carbon atoms is, for example, 2 to 7, and preferably 2 to 5. The greater the number of carbon atoms, the more hydrophobic the cured product becomes, and the less moisture permeates the cured product. The polyalkylene glycol di(meth)acrylate preferably contains at least one compound selected from the group consisting of diethylene glycol diacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, tetraethylene glycol dimethacrylate, hexaethylene glycol dimethacrylate, dipropylene glycol diacrylate, tripropylene glycol diacrylate, tripropylene glycol dimethacrylate, tritetramethylene glycol diacrylate, polyethylene glycol 200 dimethacrylate, and polyethylene glycol 200 diacrylate. Furthermore, it is preferable that the polyalkylene glycol di(meth)acrylate contains at least one compound selected from the group consisting of Sartomer product number SR230, Sartomer product number SR508NS, Daicel product number DPGDA, Sartomer product number SR306NS, Daicel product number TPGDA, Osaka Organic Chemical Industry Ltd. product number V310HP, Shin-Nakamura Chemical Co., Ltd. product number APG200, Kyoei Chemical Industry Co., Ltd. product name Light Acrylate PTMGA-250, Sartomer product number SR231NS, Kyoei Chemical Industry Co., Ltd. product name Light Ester 2EG, Sartomer product number SR205NS, Kyoei Chemical Industry Co., Ltd. product name Light Ester 3EG, Sartomer product number SR210NS, Kyoei Chemical Industry Co., Ltd. product name Light Ester 4EG, Mitsubishi Chemical Corporation product name Acryester HX, and Shin-Nakamura Chemical Co., Ltd. product number 3PG.

[0055] The alkylene oxide-modified alkylene glycol di(meth)acrylate includes, for example, propylene oxide-modified neopentyl glycol. The alkylene oxide-modified alkylene glycol di(meth)acrylate includes, for example, EBECRYL145 manufactured by Daicel Corporation.

[0056] When the acrylic compound (Y) contains a compound (Y11) having a structure represented by formula (200), it is preferable that the compound (Y11) does not contain a compound in which the value of n in formula (200) is 5 or more. (R 3 When —O)n is a polyethylene glycol skeleton, it is particularly preferred that the compound (Y11) does not contain a compound in which the value of n in formula (200) is greater than 5. Even when compound (Y11) contains a compound in which the value of n in formula (200) is greater than 5, the percentage of the compound in formula (200) in which the value of n is greater than 5 relative to the acrylic compound (Y) is preferably 20 mass% or less. Furthermore, even when compound (Y11) contains a compound in formula (200) in which the value of n is greater than 5, compound (Y11) preferably does not contain a compound in which the value of n is greater than 9, and more preferably does not contain a compound in which the value of n is greater than 7. In these cases, an increase in viscosity of composition (X) is particularly unlikely to occur.

[0057] It is particularly preferred that the polyfunctional acrylic compound (Y1) contains a polyalkylene glycol di(meth)acrylate, which has low viscosity and is not easily volatile, and therefore can contribute to lowering the viscosity of the composition (X), improving the storage stability of the composition (X), and reducing outgassing from the cured product.

[0058] When the polyfunctional acrylic compound (Y1) contains a polyalkylene glycol di(meth)acrylate, the proportion of the polyalkylene glycol di(meth)acrylate relative to the acrylic compound (Y) is preferably 40% by mass or more and 80% by mass or less. When the proportion of the polyalkylene glycol di(meth)acrylate is 40% by mass or more, the viscosity of the composition (X) can be effectively reduced. When the proportion of the polyalkylene glycol di(meth)acrylate is 80% by mass or less, the proportion of compounds having three or more (meth)acryloyl groups in the molecule increases, thereby increasing the reactivity of the composition (X) and the glass transition temperature of the cured product. This proportion is more preferably 42% by mass or more and 75% by mass or less, and even more preferably 45% by mass or more and 70% by mass or less.

[0059] The polyfunctional acrylic compound (Y1) may contain a compound having three or more radically polymerizable functional groups, including (meth)acryloyl groups, in one molecule. In this case, the polyfunctional acrylic compound (Y1) may contain, for example, at least one selected from the group consisting of trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, and pentaerythritol tetra(meth)acrylate. In this case, the glass transition temperature of the cured product can be particularly increased, and therefore the heat resistance of the cured product can be particularly improved.

[0060] The polyfunctional acrylic compound (Y1) preferably contains pentaerythritol tetra(meth)acrylate. In this case, the glass transition temperature of the cured product can be particularly increased, and the reactivity of the composition (X) can be improved. The improved reactivity of the composition (X) allows the composition (X) to be easily cured even in an oxygen-containing environment such as the air atmosphere.

[0061] When the polyfunctional acrylic compound (Y1) contains pentaerythritol tetra(meth)acrylate, the ratio of pentaerythritol tetra(meth)acrylate to the acrylic compound (Y) is preferably 0.5% by mass or more and 10% by mass or less. In this case, high reactivity and low viscosity of the composition (X) can be achieved at the same time. This ratio is more preferably 1% by mass or more and 9% by mass or less, and even more preferably 2% by mass or more and 8% by mass or less.

[0062] The polyfunctional acrylic compound (Y1) may have at least one of a benzene ring, an alicyclic ring, and a polar group. The polar group is, for example, at least one of an OH group and an NHCO group. In this case, shrinkage during curing of the composition (X) can be particularly reduced. Furthermore, adhesion between the cured product and inorganic compounds such as silicon nitride and silicon oxide can be improved. The polyfunctional acrylic compound (Y1) preferably contains at least one compound selected from the group consisting of tricyclodecane dimethanol diacrylate, bisphenol A polyethoxydiacrylate, bisphenol F polyethoxydiacrylate, trimethylolpropane triacrylate, and pentaerythritol triacrylate. These compounds can particularly reduce shrinkage during curing of the composition (X). Furthermore, these compounds can also improve adhesion between the cured product and inorganic compounds such as silicon nitride and silicon oxide.

[0063] If the adhesion between the cured product and the inorganic material is improved, when the optical component is overlaid with a film made of an inorganic material (inorganic film) such as a SiN film, high adhesion between the optical component and the inorganic film is likely to be obtained.

[0064] It is particularly preferable that the polyfunctional acrylic compound (Y1) contains polyalkylene glycol di(meth)acrylate and pentaerythritol tetra(meth)acrylate. In this case, the composition (X) has low viscosity and excellent reactivity. Therefore, the composition (X) can be easily cured even in an oxygen-containing environment such as the air atmosphere.

[0065] The acrylic compound (Y) preferably contains a monofunctional acrylic compound (Y2) having only one (meth)acryloyl group as a radical polymerizable functional group in one molecule, which can suppress shrinkage of the composition (X) during curing.

[0066] When the acrylic compound (Y) contains a monofunctional acrylic compound (Y2), the amount of the monofunctional acrylic compound (Y2) relative to the total amount of the acrylic compounds (Y) is preferably greater than 0% by mass and less than 50% by mass. When the amount of the monofunctional acrylic compound (Y2) is greater than 0% by mass, shrinkage during curing of the composition (X) can be suppressed. Furthermore, when the amount of the monofunctional acrylic compound (Y2) is 50% by mass or less, the amount of the polyfunctional acrylic compound (Y1) can be 50% by mass or more, thereby particularly improving the heat resistance of the cured product. The amount of the monofunctional acrylic compound (Y2) is more preferably 5% by mass or more, even more preferably 30% by mass or less, and particularly preferably 20% by mass or less.

[0067] Examples of the monofunctional acrylic compound (Y2) include tetrahydrofurfuryl acrylate, isobornyl acrylate, 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, isobutyl acrylate, t-butyl acrylate, isooctyl acrylate, 2-methoxyethyl acrylate, methoxytriethylene glycol acrylate, 2-ethoxyethyl acrylate, 3-methoxybutyl acrylate, ethoxyethyl acrylate, butoxyethyl acrylate, ethoxydiethylene glycol acrylate, methyl ... Toxidixylethyl acrylate, ethyl diglycol 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)-nylphenol acrylate, methoxypolyethylene glycol (350) monoacrylate, methoxypolyethylene glycol (550) monoacrylate, phenoxyethyl acrylate, cyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl acrylate, methylphenoxyethyl acrylate, 4-t-butylcyclohexyl acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, tributary The composition contains at least one compound selected from the group consisting of bromophenyl acrylate, ethoxylated tribromophenyl acrylate, 2-phenoxyethyl acrylate, an ethylene oxide adduct of 2-phenoxyethyl acrylate, a propylene oxide adduct of 2-phenoxyethyl acrylate, acryloylmorpholine, morpholin-4-yl acrylate, dicyclopentanyl acrylate, phenoxydiethylene glycol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 1,4-cyclohexanedimethanol monoacrylate, 3-methacryloyloxymethyl cyclohexene oxide, and 3-acryloyloxymethyl cyclohexene oxide.

[0068] The monofunctional acrylic compound (Y2) may contain at least one compound selected from the group consisting of compounds having an alicyclic structure and compounds having a cyclic ether structure.

[0069] The compound having an alicyclic structure includes at least one compound selected from the group consisting of, for example, phenoxyethyl acrylate, cyclohexyl (meth)acrylate, dicyclopentanyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl acrylate, methylphenoxyethyl acrylate, 4-t-butylcyclohexyl acrylate, caprolactone-modified tetrahydrofurfuryl acrylate, tribromophenyl acrylate, ethoxylated tribromophenyl acrylate, 2-phenoxyethyl acrylate, an ethylene oxide adduct of 2-phenoxyethyl acrylate, a propylene oxide adduct of 2-phenoxyethyl acrylate, acryloylmorpholine, morpholin-4-yl acrylate, isobornyl acrylate, dicyclopentanyl acrylate, phenoxydiethylene glycol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, and 1,4-cyclohexanedimethanol monoacrylate.

[0070] The number of ring members in the cyclic ether structure in the compound having a cyclic ether structure is preferably 3 or more, more preferably 3 to 4. The number of carbon atoms contained in the cyclic ether structure is preferably 2 to 9, more preferably 2 to 6. The compound having a cyclic ether structure contains, for example, at least one compound selected from the group consisting of 3-methacryloyloxymethyl cyclohexene oxide and 3-acryloyloxymethyl cyclohexene oxide.

[0071] The acrylic compound (Y) may contain a compound having silicon in its molecular skeleton. In this case, the adhesion between the cured product and the inorganic material is improved. The compound having silicon in its molecular skeleton may contain at least one compound selected from the group consisting of 3-(trimethoxysilyl)propyl acrylate (e.g., product number KBM5103 manufactured by Shin-Etsu Chemical Co., Ltd.) and (meth)acrylic group-containing alkoxysilane oligomer (e.g., product number KR-513 manufactured by Shin-Etsu Chemical Co., Ltd.).

[0072] The acrylic compound (Y) may contain a compound having phosphorus in its molecular structure. In this case, the adhesion between the cured product and the inorganic material is improved. Examples of compounds having phosphorus in their molecular structure include acid phosphoxy (meth)acrylates, such as acid phosphoxy polyoxypropylene glycol monomethacrylate.

[0073] The acrylic compound (Y) may contain a compound having nitrogen in its molecular skeleton. In this case, the adhesion between the cured product and inorganic materials is improved. Furthermore, the reactivity of the acrylic compound (Y) is likely to be improved, thereby reducing the occurrence of outgassing from the cured product. Examples of compounds having nitrogen in their molecular skeleton include at least one compound selected from the group consisting of compounds having a morpholine skeleton, such as acryloylmorpholine and morpholin-4-yl acrylate, diethylacrylamide, dimethylaminopropylacrylamide, and pentamethylpiperidyl methacrylate.

[0074] It is particularly preferred that the acrylic compound (Y) contains a compound having a morpholine skeleton. In this case, the reactivity of the composition (X) can be further improved, and the curability of the composition (X) can be further enhanced even under atmospheric conditions. It is particularly preferred that the acrylic compound (Y) contains at least one of acryloylmorpholine and morpholin-4-yl acrylate. In this case, shrinkage during curing of the composition (X) can be suppressed. In addition, the viscosity of acryloylmorpholine and morpholin-4-yl acrylate is low, and therefore these compounds are unlikely to increase the viscosity of the composition (X). Furthermore, since these compounds are unlikely to volatilize, the storage stability of the composition (X) can be easily improved.

[0075] The ratio of the compound having a morpholine skeleton to the acrylic compound (Y) is preferably 5% by mass or more and 50% by mass or less. In this case, there is an advantage that outgassing from the cured product of the composition (X) is less likely to occur. This ratio is more preferably 7% by mass or more and 45% by mass or less, and even more preferably 10% by mass or more and 40% by mass or less.

[0076] The acrylic compound (Y) may contain a compound having an isobornyl skeleton, such as one or more compounds selected from the group consisting of isobornyl acrylate and isobornyl methacrylate.

[0077] The acrylic compound (Y) may contain a component consisting of a compound having at least one skeleton selected from the group consisting of a dicyclopentadiene skeleton, a dicyclopentanyl skeleton, a dicyclopentenyl skeleton, and a bisphenol skeleton. Specifically, the acrylic compound (Y) may contain at least one compound selected from the group consisting of tricyclodecane dimethanol diacrylate, bisphenol A polyethoxydiacrylate, and bisphenol F polyethoxydiacrylate. In this case, the adhesion between the cured product and inorganic materials can be improved.

[0078] The acrylic compound (Y) may contain a compound represented by the following formula (100): In this case, the reactivity of the composition (X) can be increased, and the adhesion between the cured product and the inorganic material can be improved.

[0079] [ka]

[0080] In formula (100), R 0 is H or a methyl group. X is a single bond or a divalent hydrocarbon group. R 1 From R 11 each of which is H, an alkyl group, or -R 12 -OH, R 12 is an alkylene group and R 1 From R 11 At least one of the groups is an alkyl group or -R 12 -OH. R 1 From R 11 are not chemically bonded to each other.

[0081] Specifically, for example, the acrylic compound (Y) may contain at least one compound selected from the group consisting of a compound represented by the following formula (110), a compound represented by the following formula (120), and a compound represented by the following formula (130).

[0082] [ka]

[0083] The radically polymerizable compound (A1) may contain a radically polymerizable compound (Z) other than the acrylic compound (Y). The amount of the radically polymerizable compound (Z) relative to the total amount of the acrylic compound (Y) and the radically polymerizable compound (Z) is, for example, 10% by mass or less. The radically polymerizable compound (Z) may contain either or both of a polyfunctional radically polymerizable compound (Z1) having two or more radically polymerizable functional groups per molecule and a monofunctional radically polymerizable compound (Z2) having only one radically polymerizable functional group per molecule. The polyfunctional radically polymerizable compound (Z1) may contain, for example, at least one compound selected from the group consisting of aromatic urethane oligomers, aliphatic urethane oligomers, epoxy acrylate oligomers, polyester acrylate oligomers, and other special oligomers, each having two or more ethylenic double bonds per molecule. However, the components that the polyfunctional radically polymerizable compound (Z1) may contain are not limited to those described above. The monofunctional radical polymerizable compound (Z2) contains at least one compound selected from the group consisting of, for example, N-vinylformamide, vinylcaprolactam, vinylpyrrolidone, phenylglycidyl ether, p-tert-butylphenylglycidyl ether, butylglycidyl ether, 2-ethylhexylglycidyl ether, allylglycidyl ether, 1,2-butylene oxide, 1,3-butadiene monoxide, 1,2-epoxydodecane, epichlorohydrin, 1,2-epoxydecane, styrene oxide, cyclohexene oxide, 3-vinylcyclohexene oxide, 4-vinylcyclohexene oxide, N-vinylpyrrolidone, and N-vinylcaprolactam. However, the components that the monofunctional radical polymerizable compound (Z2) can contain are not limited to those listed above.

[0084] When the radical polymerizable compound (A1) contains a radical polymerizable compound (Z), the radical polymerizable compound (Z) may contain a compound having nitrogen in its molecular skeleton. The compound having nitrogen in its molecular skeleton includes, for example, at least one compound selected from the group consisting of N-vinylformamide, N-vinylpyrrolidone, and N-vinylcaprolactam. In this case, the adhesion between the cured product and inorganic materials is improved, as in the case where the acrylic compound (Y) contains a compound having nitrogen in its molecular skeleton.

[0085] In other words, the radically polymerizable compound (A1) preferably contains a compound having nitrogen in its molecular skeleton. This compound having nitrogen in its molecular skeleton may contain a compound contained in the acrylic compound (Y) or a compound contained in the radically polymerizable compound (Z). In this case, the adhesion between the cured product and the inorganic material is improved. The proportion of the compound having nitrogen in its molecular skeleton relative to the total amount of the radically polymerizable compound (A1) is preferably 5% by mass or more and 80% by mass or less. A proportion of 5% by mass or more particularly improves the adhesion between the cured product and the inorganic material. A proportion of 80% by mass or less prevents the compound having nitrogen in its molecular skeleton from impairing the storage stability of the composition (X) and from generating satellites when the composition (X) is sprayed by an inkjet method. This prevents the inkjetability of the composition (X) from being impaired. Furthermore, outgassing due to the compound having nitrogen in its molecular skeleton can be reduced. This proportion is more preferably 10% by mass or more and 70% by mass or less, even more preferably 20% by mass or more and 60% by mass or less, and particularly preferably 25% by mass or more and 50% by mass or less.

[0086] The ratio of the total amount of monofunctional compounds in the radical polymerizable compound (A1) (i.e., the total amount of the monofunctional acrylic compound (Y2) and the monofunctional radical polymerizable compound (Z2)) to the total amount of the radical polymerizable compound (A1) is preferably 70% by mass or less. In this case, outgassing caused by the monofunctional compounds is less likely to occur. This ratio is more preferably 60% by mass or less, and even more preferably 50% by mass or less.

[0087] The photoradical polymerization initiator (B1) is not particularly limited as long as it is a compound that generates radical species when irradiated with ultraviolet light. The photoradical polymerization initiator (B1) contains at least one compound selected from the group consisting of, for example, aromatic ketones, acylphosphine oxide compounds, aromatic onium salt compounds, organic peroxides, thio compounds (thioxanthone compounds, thiophenyl group-containing compounds, etc.), hexaarylbiimidazole compounds, oxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon-halogen bond, and alkylamine compounds.

[0088] The ratio of the photoradical polymerization initiator (B1) to the radical polymerizable compound (A1) is preferably 6% by mass or more. In this case, the composition (X) can have good UV curability, and can also have good UV curability in the air. This ratio is more preferably 7% by mass or more, and even more preferably 8% by mass or more. This ratio is, for example, 30% by mass or less, preferably 20% by mass or less, and even more preferably 18% by mass or less.

[0089] The photoradical polymerization initiator (B) preferably contains a component having photobleachability. In this case, the cured product of the composition (X) is likely to have good light transmittance. The ratio of the component having photobleachability to the radical polymerizable compound (A1) is preferably 3% by mass or more. This ratio is more preferably 7% by mass or more, and even more preferably 8% by mass or more. This ratio is, for example, 30% by mass or less, preferably 25% by mass or less, and even more preferably 20% by mass or less.

[0090] The component having photobleachability contains, for example, at least one of an acylphosphine oxide-based photoinitiator and a compound having photobleachability among oxime ester-based photoinitiators.

[0091] The photoradical polymerization initiator (B) preferably contains a component having a sensitizer skeleton in its molecule. The sensitizer skeleton includes, for example, at least one of a 9H-thioxanthen-9-one skeleton and an anthracene skeleton. That is, the photoradical polymerization initiator (B) preferably contains a component having at least one of a 9H-thioxanthen-9-one skeleton and an anthracene skeleton.

[0092] The photoradical polymerization initiator (B) preferably contains an oxime ester photoinitiator, regardless of whether it is photobleachable. The oxime ester photoinitiator can improve the curability of the composition (X). Therefore, the composition (X) can be easily cured even in an oxygen-containing environment such as the air atmosphere, and the cured product can be less likely to outgas.

[0093] The oxime ester photoinitiator preferably contains a compound having an aromatic ring, more preferably contains a compound having a fused ring containing an aromatic ring, and further preferably contains a compound having a fused ring containing a benzene ring and a heterocycle, in order to reduce the likelihood of contamination of composition (X) and a production equipment due to the generation of decomposition products from composition (X), and to further reduce the likelihood of outgassing from the cured product.

[0094] The oxime ester photoinitiator may contain at least one compound selected from the group consisting of 1,2-octadione-1-[4-(phenylthio)-, 2-(o-benzoyloxime)], and ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(o-acetyloxime), as well as oxime ester photoinitiators described in JP 2000-80068 A, JP 2001-233842 A, JP 2010-527339 A, JP 2010-527338 A, JP 2013-041153 A, JP 2015-93842 A, and the like. The oxime ester photoinitiator may contain at least one compound selected from the group consisting of commercially available products having a carbazole skeleton, such as Irgacure OXE-02 (manufactured by BASF), Adeka Arcles NCI-831, N-1919 (manufactured by ADEKA Corporation), and TR-PBG-304 (manufactured by Changzhou New Power Electronic Materials Co., Ltd.), diphenyl sulfide skeletons, such as Irgacure OXE-01, Adeka Arcles NCI-930 (manufactured by ADEKA Corporation), TR-PBG-345, and TR-PBG-3057 (all manufactured by Changzhou New Power Electronic Materials Co., Ltd.), and fluorene skeletons, such as TR-PBG-365 (manufactured by Changzhou New Power Electronic Materials Co., Ltd.) and SPI-04 (manufactured by Sanyang Co., Ltd.). In particular, it is preferable for the oxime ester photoinitiator to contain a compound having a diphenyl sulfide skeleton or a fluorene skeleton, as this makes the cured product less likely to discolor due to photobleaching. It is also preferable that the oxime ester photoinitiator contains a compound having a carbazole skeleton, since the exposure sensitivity is likely to be increased.

[0095] It is also preferable that the oxime ester photoinitiator contains two or more compounds. In this case, for example, by containing two or more compounds with different exposure sensitivity in the oxime ester photoinitiator, it is possible to reduce the amount of the photoradical polymerization initiator (B) while maintaining good exposure sensitivity, and therefore it is possible to further reduce the generation of outgassing from the cured product.

[0096] The photobleachable oxime ester compound contains, for example, at least one of the compound represented by the following formula (401) and the compound represented by the following formula (402). Of these, the compound represented by formula (402) has particularly high sensitivity, and therefore is particularly likely to enhance the photocurability of composition (X), making it easy to achieve UV curability of composition (X) in the air.

[0097] [ka]

[0098] [ka]

[0099] The acylphosphine oxide compound contains, for example, at least one selected from the group consisting of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and bis(2,4,6-trimethylbenzoyl)diphenylphosphine oxide.

[0100] The photoradical polymerization initiator (B1) may contain a sensitizer as a part of the photoradical polymerization initiator (B1). The sensitizer can accelerate the radical generation reaction of the photoradical polymerization initiator (B1), thereby improving the reactivity of the radical polymerization and increasing the crosslink density. The sensitizer may contain at least one compound selected from the group consisting of, for example, 9,10-dibutoxyanthracene, 9-hydroxymethylanthracene, thioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, anthraquinone, 1,2-dihydroxyanthraquinone, 2-ethylanthraquinone, 1,4-diethoxynaphthalene, p-dimethylaminoacetophenone, p-diethylaminoacetophenone, p-dimethylaminobenzophenone, p-diethylaminobenzophenone, 4,4'-bis(dimethylamino)benzophenone, 4,4'-bis(diethylamino)benzophenone, p-dimethylaminobenzaldehyde, and p-diethylaminobenzaldehyde. However, the components that the sensitizer may contain are not limited to those listed above.

[0101] The content of the sensitizer in composition (X) is, for example, 0.1 to 5 parts by mass, and preferably 0.1 to 3 parts by mass, per 100 parts by mass of the solid content of composition (X). When the content of the sensitizer is within this range, composition (X) can be cured in air, eliminating the need to cure composition (X) in an inert atmosphere such as a nitrogen atmosphere.

[0102] The composition (X) may contain a polymerization accelerator in addition to the photoradical polymerization initiator (B1). The polymerization accelerator contains, for example, an amine compound such as ethyl p-dimethylaminobenzoate, 2-ethylhexyl p-dimethylaminobenzoate, methyl p-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, or butoxyethyl p-dimethylaminobenzoate. However, the components that the polymerization accelerator may contain are not limited to those listed above.

[0103] When the photopolymerizable compound (A) contains a cationically polymerizable compound (W), the cationically polymerizable compound (W) contains, for example, at least one of a polyfunctional cationically polymerizable compound (W1) and a monofunctional cationically polymerizable compound (W2).

[0104] The polyfunctional cationically polymerizable compound (W1) can contain either or both of a polyfunctional cationically polymerizable compound (W11) that does not have a siloxane skeleton and a polyfunctional cationically polymerizable compound (W12) that has a siloxane skeleton.

[0105] The polyfunctional cationically polymerizable compound (W11) does not have a siloxane skeleton and has two or more cationically polymerizable functional groups per molecule. The number of cationically polymerizable functional groups per molecule of the polyfunctional cationically polymerizable compound (W11) is preferably 2 to 4, and more preferably 2 to 3.

[0106] The cationically polymerizable functional group is, for example, at least one group selected from the group consisting of an epoxy group, an oxetane group, and a vinyl ether group.

[0107] The polyfunctional cationically polymerizable compound (W11) contains at least one compound selected from the group consisting of, for example, polyfunctional alicyclic epoxy compounds, polyfunctional heterocyclic epoxy compounds, polyfunctional oxetane compounds, alkylene glycol diglycidyl ethers, and alkylene glycol monovinyl monoglycidyl ethers.

[0108] The polyfunctional alicyclic epoxy compound contains, for example, either one or both of a compound represented by the following formula (1) and a compound represented by the following formula (20).

[0109] [ka]

[0110] In formula (1), R 1 ~R 18are each independently a hydrogen atom, a halogen atom, or a hydrocarbon group. The hydrocarbon group preferably has 1 to 20 carbon atoms. Examples of the hydrocarbon group include alkyl groups having 1 to 20 carbon atoms, such as methyl, ethyl, and propyl; alkenyl groups having 2 to 20 carbon atoms, such as vinyl and allyl; and alkylidene groups having 2 to 20 carbon atoms, such as ethylidene and propylidene. The hydrocarbon group may contain an oxygen atom or a halogen atom. 1 ~R 18 are each independently preferably a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, more preferably a hydrogen atom or a methyl group, and most preferably a hydrogen atom.

[0111] In formula (1), X is a single bond or a divalent organic group, and the organic group is, for example, —CO—O—CH 2 —.

[0112] Examples of the compound represented by formula (1) include a compound represented by the following formula (1a) and a compound represented by the following formula (1b).

[0113] [ka]

[0114] [ka]

[0115] [ka]

[0116] In formula (20), R 1 ~R 12are each independently a hydrogen atom, a halogen atom, or a hydrocarbon group having 1 to 20 carbon atoms. Examples of halogen atoms include fluorine, chlorine, bromine, and iodine atoms. Examples of hydrocarbon groups having 1 to 20 carbon atoms include alkyl groups having 1 to 20 carbon atoms such as methyl, ethyl, and propyl; alkenyl groups having 2 to 20 carbon atoms such as vinyl and allyl; or alkylidene groups having 2 to 20 carbon atoms such as ethylidene and propylidene. The hydrocarbon group having 1 to 20 carbon atoms may contain an oxygen atom or a halogen atom.

[0117] R 1 ~R 12 are each independently preferably a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, more preferably a hydrogen atom or a methyl group, and most preferably a hydrogen atom.

[0118] Examples of the compound represented by formula (20) include tetrahydroindene diepoxide represented by formula (20a) below.

[0119] [ka]

[0120] The polyfunctional heterocyclic epoxy compound contains, for example, a trifunctional epoxy compound as shown in the following formula (2).

[0121] [ka]

[0122] The polyfunctional oxetane compound includes, for example, a bifunctional oxetane compound represented by the following formula (3).

[0123] [ka]

[0124] The alkylene glycol diglycidyl ether contains at least one compound selected from the group consisting of compounds represented by the following formulas (4) to (7).

[0125] [ka]

[0126] [ka]

[0127] [ka]

[0128] [ka]

[0129] The alkylene glycol monovinyl monoglycidyl ether contains, for example, a compound represented by the following formula (8).

[0130] [ka]

[0131] More specifically, the polyfunctional cationically polymerizable compound (W11) may contain at least one component selected from the group consisting of, for example, CELLOXIDE 2021P and CELLOXIDE 8010 manufactured by Daicel, TEPIC-VL manufactured by Nissan Chemical, OXT-221 manufactured by Toagosei, and 1,3-PD-DEP, 1,4-BG-DEP, 1,6-HD-DEP, NPG-DEP, and butylene glycol monovinyl monoglycidyl ether manufactured by Yokkaichi Chemical Industry.

[0132] The polyfunctional cationically polymerizable compound (W11) preferably contains a polyfunctional alicyclic epoxy compound, in which case the composition (X) can have particularly high cationic polymerization reactivity.

[0133] The polyfunctional alicyclic epoxy compound preferably contains either or both of the compound represented by formula (1) and the compound represented by formula (20). In this case, composition (X) can have higher cationic polymerization reactivity.

[0134] When the polyfunctional alicyclic epoxy compound contains a compound represented by formula (1), the compound represented by formula (1) preferably contains a compound represented by formula (1a). In this case, composition (X) can have higher cationic polymerization reactivity and particularly low viscosity.

[0135] Furthermore, since the compound represented by formula (20) in particular has a low viscosity, when the compound represented by formula (20) is contained, the composition (X) can have good UV curability and a particularly low viscosity. Furthermore, the compound represented by formula (20) has a low viscosity but is not easily volatile. Therefore, even if the composition (X) contains the compound represented by formula (20), the composition (X) is not likely to undergo a change in composition due to the volatilization of the compound represented by formula (20). Therefore, by containing the compound represented by formula (20), the viscosity of the composition (X) can be reduced without impairing storage stability.

[0136] The compound represented by formula (20) can be synthesized, for example, by oxidizing a cyclic olefin compound having a tetrahydroindene skeleton using an oxidizing agent.

[0137] The compound represented by formula (20) may contain four stereoisomers based on the configuration of the two epoxy rings. The compound represented by formula (20) may contain any of the four stereoisomers. That is, the compound represented by formula (20) may contain at least one component selected from the group consisting of the four stereoisomers. In the compound represented by formula (20), the total proportion of the exo-endo isomer and the endo-endo isomer among the four stereoisomers is preferably 10% by mass or less, more preferably 5% by mass or less, based on the total epoxy compound (A1). In this case, the heat resistance of the cured product can be improved. The proportion of a specific stereoisomer in the compound represented by formula (20) can be determined based on the peak area ratio appearing in a chromatogram obtained by gas chromatography.

[0138] In order to reduce the amount of exo-endo isomer and endo-endo isomer in the compound represented by formula (20), an appropriate method can be applied, such as a method of subjecting the compound represented by formula (20) to precision distillation or a method of applying column chromatography using silica gel or the like as a packing material.

[0139] When the composition (X) contains a polyfunctional cationically polymerizable compound (W11), the proportion of the polyfunctional cationically polymerizable compound (W11) relative to the total amount of resin components is preferably within the range of 5 to 95% by mass. The term "resin components" refers to the cationically polymerizable compounds in the composition (X), including the polyfunctional cationically polymerizable compound (W1) and the monofunctional cationically polymerizable compound (W2). When the proportion of the polyfunctional cationically polymerizable compound (W11) is 5% by mass or more, the composition (X) can exhibit particularly excellent reactivity during the photocationic polymerization reaction, thereby enabling the cured product to have high strength (hardness). When the composition (X) contains a moisture absorbent (C), when the proportion of the polyfunctional cationically polymerizable compound (W11) is 95% by mass or less, the moisture absorbent (C) can be dispersed particularly uniformly in the composition (X). The proportion of this polyfunctional cationically polymerizable compound (W11) is more preferably 12% by mass or more, even more preferably 15% by mass or more, even more preferably 20% by mass or more, and particularly preferably 25% by mass or more. The proportion of this polyfunctional cationically polymerizable compound (W11) is more preferably 85% by mass or less, even more preferably 60% by mass or less. For example, the proportion of the polyfunctional cationically polymerizable compound (W11) is preferably within the range of 20 to 60% by mass.

[0140] When the polyfunctional cationically polymerizable compound (W11) contains a polyfunctional alicyclic epoxy compound, the polyfunctional alicyclic epoxy compound may be a part or the whole of the polyfunctional cationically polymerizable compound (W11). The ratio of the polyfunctional alicyclic epoxy compound to the polyfunctional cationically polymerizable compound (W11) is preferably within the range of 15 to 100% by mass. When this ratio is 15% by mass or more, the polyfunctional alicyclic epoxy compound can particularly contribute to improving the UV curability of the composition (X).

[0141] The polyfunctional cationically polymerizable compound (W12) has a siloxane skeleton and two or more cationically polymerizable functional groups per molecule. The number of cationically polymerizable functional groups per molecule of the polyfunctional cationically polymerizable compound (W12) is preferably 2 to 6, more preferably 2 to 4. The polyfunctional cationically polymerizable compound (W12) can contribute to improving the cationic polymerization reactivity of the composition (X) and also contribute to improving the heat discoloration resistance of the cured product and optical components. The polyfunctional cationically polymerizable compound (W12) can also contribute to lowering the elastic modulus of the cured product and optical components. When the composition (X) contains a moisture absorbent, the polyfunctional cationically polymerizable compound (W12) can also contribute to improving the dispersibility of the moisture absorbent in the composition (X) and the cured product.

[0142] The polyfunctional cationically polymerizable compound (W12) is preferably a liquid at 25° C. In particular, the viscosity of the polyfunctional cationically polymerizable compound (W12) at 25° C. is preferably within the range of 10 to 300 mPa s. In this case, an increase in the viscosity of the composition (X) can be suppressed.

[0143] The cationically polymerizable functional group contained in the polyfunctional cationically polymerizable compound (W12) is, for example, at least one group selected from the group consisting of an epoxy group, an oxetane group, and a vinyl ether group.

[0144] The siloxane skeleton of the polyfunctional cationically polymerizable compound (W12) may be linear, branched, or cyclic. The number of Si atoms in the siloxane skeleton is preferably within the range of 2 to 14. In this case, the composition (X) can have a particularly low viscosity. The number of Si atoms is more preferably within the range of 2 to 10, even more preferably within the range of 2 to 7, and particularly preferably within the range of 3 to 6.

[0145] The polyfunctional cationically polymerizable compound (W12) contains, for example, at least one of a compound represented by formula (10) and a compound represented by formula (11).

[0146] [ka]

[0147] [ka]

[0148] In each of formulas (10) and (11), R is a single bond or a divalent organic group, and is preferably an alkylene group. Y is a siloxane skeleton, which may be linear, branched, or cyclic, and the number of Si atoms therein is preferably within a range of 2 to 14, more preferably within a range of 2 to 10, even more preferably within a range of 2 to 7, and particularly preferably within a range of 3 to 6. n is an integer of 2 or greater, and is preferably within a range of 2 to 4.

[0149] More specifically, for example, the polyfunctional cationically polymerizable compound (W12) contains a compound represented by the following formula (10a).

[0150] [ka]

[0151] R in formula (10a) is a single bond or a divalent organic group, and is preferably an alkylene group having 1 to 4 carbon atoms. n in formula (10a) is an integer of 0 or greater. n is preferably within the range of 0 to 12, more preferably within the range of 0 to 8, even more preferably within the range of 0 to 5, and particularly preferably within the range of 1 to 4.

[0152] The compound represented by formula (10a) preferably contains a compound represented by the following formula (30): That is, the polyfunctional cationically polymerizable compound (W12) preferably contains a compound represented by the following formula (30):

[0153] More specifically, the polyfunctional cationically polymerizable compound (W12) preferably contains at least one component selected from the group consisting of product numbers X-40-2669, X-40-2670, X-40-2715, X-40-2732, X-22-169AS, X-22-169B, X-22-2046, X-22-343, X-22-163, and X-22-163B manufactured by Shin-Etsu Chemical Co., Ltd.

[0154] The polyfunctional cationically polymerizable compound (W12) preferably has an alicyclic epoxy structure, and it is particularly preferred if the polyfunctional cationically polymerizable compound (W12) contains a compound represented by formula (10a). The compound represented by formula (10a) can particularly contribute to improving the cationic polymerization reactivity and reducing the viscosity of the composition (X), as well as to improving the heat discoloration resistance and reducing the elastic modulus of the cured product and optical components. When the composition (X) contains a moisture absorbent (C), it can also particularly contribute to improving the dispersibility of the moisture absorbent (C) in the composition (X).

[0155] When the composition (X) contains a polyfunctional cationically polymerizable compound (W12), the proportion of the polyfunctional cationically polymerizable compound (W12) relative to the total amount of the resin components is preferably within the range of 5 to 95 mass %. In this case, when the composition (X) contains a moisture absorbent (C), the dispersibility of the moisture absorbent (C) in the composition (X) and in the cured product is particularly improved, and the composition (X) can have particularly high photocationic polymerization reactivity.

[0156] The monofunctional cationically polymerizable compound (W2) has only one cationically polymerizable functional group per molecule, which is, for example, at least one group selected from the group consisting of an epoxy group, an oxetane group, and a vinyl ether group.

[0157] The viscosity of the monofunctional cationically polymerizable compound (W2) at 25°C is preferably 8 mPa·s or less. In this case, even if the composition (X) does not contain a solvent, the monofunctional cationically polymerizable compound (W2) can reduce the viscosity of the composition (X). In particular, the viscosity of the monofunctional cationically polymerizable compound (W2) at 25°C is preferably within the range of 0.1 to 8 mPa·s.

[0158] The monofunctional cationically polymerizable compound (W2) may contain, for example, at least one compound selected from the group consisting of compounds represented by the following formulas (12) to (17) and limonene oxide.

[0159] [ka]

[0160] [ka]

[0161] [ka]

[0162] [ka]

[0163] [ka]

[0164] [ka]

[0165] The proportion of the monofunctional cationically polymerizable compound (W2) relative to the total amount of resin components is preferably within the range of 5 to 50% by mass. When the proportion of the monofunctional cationically polymerizable compound (W2) is 5% by mass or more, the viscosity of the composition (X) can be particularly reduced. When the proportion of the monofunctional cationically polymerizable compound (W2) is 50% by mass or less, the composition (X) can exhibit particularly excellent reactivity during the photocationic polymerization reaction, thereby enabling the cured product to have high strength (hardness). The proportion of this monofunctional cationically polymerizable compound (W2) is more preferably 10% by mass or more, and even more preferably 15% by mass or more. The proportion of this monofunctional cationically polymerizable compound (W2) is more preferably 40% by mass or less, even more preferably 35% by mass or less, and particularly preferably 30% by mass or less. When the proportion of the monofunctional cationically polymerizable compound (W2) is particularly 35% by mass or less, the amount of volatilization of the components in the composition (X) during storage can be effectively reduced, and therefore the properties of the composition (X) are less likely to be impaired even when the composition (X) is stored for a long period of time. Furthermore, the occurrence of tackiness in the cured product can be particularly suppressed. For example, the proportion of the monofunctional cationically polymerizable compound (W2) is preferably within the range of 10 to 35% by mass.

[0166] In particular, when the composition (X) contains a polyfunctional cationically polymerizable compound (W11) and a polyfunctional cationically polymerizable compound (W12), the proportion of the polyfunctional cationically polymerizable compound (W11) is preferably within a range of 30 to 60% by mass, the proportion of the polyfunctional cationically polymerizable compound (W12) is preferably within a range of 15 to 30% by mass, and the proportion of the monofunctional cationically polymerizable compound (W2) is preferably within a range of 15 to 40% by mass, based on the total amount of the resin components. In this case, the composition (X) can achieve a good balance of good storage stability, low viscosity, and good cationic polymerization reactivity, and further achieve a good balance of excellent transparency, excellent hygroscopicity, and a high refractive index of the cured product.

[0167] When the cationically polymerizable compound (W) contains a compound represented by formula (3) and a compound represented by formula (16), by adjusting the ratio of the two, it is possible to appropriately adjust the ease of progress of the curing reaction when preparing a photocured product from the composition (X), while achieving a low viscosity and improved storage stability of the composition (X).

[0168] The amount of the compound represented by formula (16) is appropriately adjusted so that composition (X) has the above-mentioned properties. For example, the amount of the compound represented by formula (16) is preferably 10% by mass or more and 40% by mass or less based on the total amount of the resin components.

[0169] The cationically polymerizable compound (W) preferably contains a compound (f1) represented by the following formula (30) (hereinafter also referred to as aromatic epoxy compound (f1)).

[0170] [ka]

[0171] In formula (30), X is at least one selected from the group consisting of halogen, H, a hydrocarbon group, and an alkylene glycol group, and when there are multiple Xs in one molecule, they may be the same or different. The hydrocarbon group is, for example, an alkyl group or an aryl group. When X is a hydrocarbon group, the number of carbon atoms in X is, for example, in the range of 1 to 10. R is a single bond or a divalent organic group. When R is a divalent organic group, the divalent organic group is, for example, an alkylene group, an oxyalkylene group, a carbonyloxyalkylene group (e.g., -CO-O-CH2-), or a -C(Ph)2-O-CH2- group. Y is H or a monovalent organic group. When Y is a monovalent organic group, the monovalent organic group is, for example, an alkyl group or an aryl group.

[0172] When the cationically polymerizable compound (W) contains an aromatic epoxy compound (f1), the aromatic epoxy compound (f1) has a low viscosity, which facilitates the reduction of the viscosity of the composition (X). Furthermore, the aromatic epoxy compound (f1) is not easily volatilized, and therefore, even during storage, the composition (X) is unlikely to undergo changes in composition due to the volatilization of the aromatic epoxy compound (f1). Therefore, the aromatic epoxy compound (f1) facilitates the improvement of the storage stability of the composition (X). Furthermore, the aromatic epoxy compound (f1) is highly reactive, which prevents unreacted components from remaining in the cured product, thereby reducing the risk of outgassing from the cured product. Furthermore, the aromatic epoxy compound (f1) facilitates the increase of the glass transition temperature of the cured product, thereby enhancing the heat resistance of the cured product.

[0173] Furthermore, when the composition (X) is ejected by an ink jet method, the aromatic epoxy compound (f1) is less likely to produce defective droplets called satellites.

[0174] R in formula (30) is preferably a single bond or an alkylene group. When n in formula (30) is 2 or 3, at least one of the multiple R in formula (30) is preferably a single bond or an alkylene group. In these cases, the reactivity of the aromatic epoxy compound (f1) tends to be high, and therefore the curability of composition (X) tends to be high when composition (X) is irradiated with ultraviolet light.

[0175] The aromatic epoxy compound (f1) preferably contains at least one compound selected from the group consisting of compounds represented by the following formulas (301) to (318).

[0176] [ka]

[0177] In particular, it is preferred that the aromatic epoxy compound (f1) contains at least one component selected from the group consisting of the compounds represented by the formulae (301) to (305), (312), (314), and (318). These compounds tend to have high reactivity because at least one epoxy group (oxirane) in the compound is bonded to a benzene ring via a single bond or an alkylene group, and therefore tend to enhance the curability of the composition (X).

[0178] The proportion of the aromatic epoxy compound (f1) relative to the total amount of the cationically polymerizable compound (W) is preferably 5% by mass or more. In this case, the above-mentioned effects of the aromatic epoxy compound (f1) are particularly easily achieved. This proportion is also preferably 95% by mass or less. In this case, the storage stability of the composition (X) is likely to be improved. This proportion is more preferably 10% by mass or more and 90% by mass or less, and even more preferably 20% by mass or more and 85% by mass or less.

[0179] It is also preferable that the cationically polymerizable compound (W) contains a compound (f2) having an oxyalkylene skeleton. The oxyalkylene skeleton is a linear skeleton consisting of one or more linear oxyalkylene units.

[0180] When the cationically polymerizable compound (W) contains the compound (f2), the compound (f2) has a low viscosity, and therefore the compound (f2) tends to lower the viscosity of the composition (X). Furthermore, the compound (f2) is not easily volatilized, and therefore, even when the composition (X) is stored, the composition (X) is not likely to change in composition due to the volatilization of the aromatic epoxy compound (f1). Therefore, the compound (f2) tends to improve the storage stability of the composition (X).

[0181] Furthermore, compound (f2) reduces the formation of defective droplets known as satellites when composition (X) is ejected by an inkjet method. Furthermore, compound (f2) can reduce the formation of satellites even when the droplet speed is increased by the inkjet method. Therefore, depending on the inkjet conditions, it is possible to increase the droplet ejection speed by the inkjet method to 4 m / s or more without generating satellites. Increasing the droplet speed reduces the influence of external disturbances on the droplet trajectory, thereby improving the dimensional accuracy of the cured product produced from composition (X). Furthermore, as described above, compound (f2) can improve the storage stability of composition (X), so that composition (X)'s characteristic of being less susceptible to satellite formation is likely to be maintained even when composition (X) is stored for a long period of time.

[0182] The oxyalkylene skeleton preferably contains a "-CCO-" structure, i.e., an oxymethylene unit. In this case, satellites are particularly unlikely to form, even when the driving frequency is changed when ejecting composition (X) by an inkjet method. In addition, compound (f2) is less likely to volatilize and tends to have a lower viscosity, and the affinity (wettability) of composition (X) for inorganic materials is likely to be increased.

[0183] The number of oxyalkylene units in the oxyalkylene skeleton of compound (f2) is preferably 1 to 8. In this case, compound (f2) tends to have a lower viscosity, which makes it particularly unlikely that satellites will be formed, and the crosslink density of the cured product tends to be high, which tends to make the glass transition temperature of the cured product particularly high. The number of oxyalkylene units is more preferably 1 to 6, and even more preferably 1 to 4.

[0184] The oxyalkylene units in the oxyalkylene skeleton of compound (f2) may have a substituent other than hydrogen. For example, the oxymethylene units contained in the oxyalkylene skeleton may have the structure "-CH(CH)-CH-O-".

[0185] The proportion of the compound (f2) is preferably 10% by mass or more relative to the cationically polymerizable compound (W), which improves inkjet properties and wettability to the substrate. It is also preferable that this proportion is 70% by weight or less, in which case the glass transition temperature can be sufficiently increased. This proportion is more preferably 15% by weight or more and 60% by weight or less, and even more preferably 20% by weight or more and 50% by weight or less.

[0186] The compound (f2) contains, for example, at least one compound selected from the group consisting of a compound (f21) having an oxyalkylene skeleton and an epoxy group, and a compound (f22) having an oxyalkylene group and an oxetane group.

[0187] Compound (f21) contains at least one compound selected from the group consisting of, for example, the compound represented by formula (1b), the compound represented by formula (4), the compound represented by formula (5), the compound represented by formula (6), the compound represented by formula (7), the compound represented by formula (8), the compound represented by formula (13), the compound represented by formula (14), etc. However, the components that compound (f21) can contain are not limited to those mentioned above.

[0188] Compound (f22) contains at least one compound selected from the group consisting of compounds represented by the above formula (3), compounds represented by formula (12), compounds represented by formula (16), and compounds represented by formula (17). Note that the components that compound (f22) can contain are not limited to those listed above.

[0189] The cationically polymerizable compound (W) preferably contains an epoxy compound and the above-mentioned compound (f22). The epoxy compound contains, for example, at least one compound containing an epoxy group, among the compounds that can be included in the cationically polymerizable compound (W). When the cationically polymerizable compound (W) contains an epoxy compound and compound (f22), the curability of the composition (X) when irradiated with ultraviolet light is enhanced, and the composition (X) is less likely to cure too rapidly. This reduces the likelihood of the cured product becoming cloudy or otherwise losing transparency. The mechanism behind this effect is presumed to be as follows: Because the reactivity of compound (f22) is lower than that of the epoxy compound, the epoxy compound reacts first when the composition (X) is irradiated with ultraviolet light. This reaction of the epoxy compound increases the curability of the composition (X). The subsequent reaction of compound (f22) reduces the likelihood of simultaneous reaction of the epoxy compound and compound (f22). This is thought to reduce the likelihood of an excessively rapid reaction. In this case, the ratio of compound (f22) to the cationically polymerizable compound (W) is preferably 20% by mass or more. In this case, compound (f22) particularly easily reduces the viscosity of composition (X) and particularly easily enhances the storage stability of composition (X). Furthermore, compound (f22) particularly easily enhances the curability of composition (X). The ratio of compound (f22) is also preferably 90% by mass or less. In this case, the curability of the cured product can be sufficiently enhanced. The ratio of compound (f22) is more preferably 10% by mass or more and 90% by mass or less, and even more preferably 20% by mass or more and 80% by mass or less. Furthermore, in this case, the ratio of the epoxy compound is preferably 10% by mass or more and 90% by mass or less, more preferably 20% by mass or more and 80% by mass or less, and even more preferably 25% by mass or more and 75% by mass or less, relative to the total amount of cationically polymerizable compound (W). In these cases, the unreacted groups in the cured product can be sufficiently reduced, thereby sufficiently enhancing the curability of the cured product.

[0190] The epoxy compound preferably contains a compound having at least one oxirane ring that does not constitute a glycidyl ether group. In this case, the epoxy compound is particularly likely to enhance the curability of the composition (X). It is more preferable that the epoxy compound contains a compound having two or more oxirane rings that do not constitute a glycidyl ether group. It is also preferable that the epoxy compound contains a compound that does not contain a glycidyl ether group. It is particularly preferable that the epoxy compound contains a compound that has two or more oxirane rings that do not constitute a glycidyl ether group and does not contain a glycidyl ether group.

[0191] It is particularly preferred that the cationically polymerizable compound (W) contains compound (f2) and an epoxy compound, and that the epoxy compound further contains the above-mentioned aromatic epoxy compound (f1). In this case, composition (X) is likely to have particularly excellent storage stability, and when composition (X) is ejected by an inkjet method, defective droplets called satellites are particularly unlikely to form. Furthermore, even when the droplet speed ejected by the inkjet method is increased, satellites are particularly unlikely to form. Furthermore, even when composition (X) is stored for a long period of time, the characteristic of composition (X) that satellites are particularly unlikely to form is particularly likely to be maintained. In this case, it is particularly preferred that compound (f2) contains compound (f22).

[0192] The total ratio of the aromatic epoxy compound (f1) and the compound (f22) to the cationically polymerizable compound (W) is preferably 55% by mass or more. In this case, the effect of the combination of the aromatic epoxy compound (f1) and the compound (f22) is particularly pronounced. This ratio is more preferably 60% by mass or more, and even more preferably 70% by mass or more. It is particularly preferred that the cationically polymerizable compound (W) contains only the aromatic epoxy compound (f1) and the compound (f22).

[0193] When the composition (X) contains the cationically polymerizable compound (W), it is preferable that the composition (X) further contains a sensitizer. In this case, the composition (X) can have particularly high cationic polymerization reactivity. The sensitizer contains, for example, one or both of 9,10-dibutoxyanthracene and 9,10-diethoxyanthracene. The ratio of the sensitizer to the cationically polymerizable compound (W) is preferably in the range of more than 0% by mass and not more than 1% by mass. In this case, the sensitizer is less likely to impair the transparency of the cured product, and therefore the cured product can have good transparency.

[0194] When the composition (X) contains a cationically polymerizable compound (W), the composition (X) preferably further contains a cationic photopolymerization initiator (B2). The cationic photopolymerization initiator (B2) is not particularly limited as long as it is a catalyst that generates a protonic acid or a Lewis acid upon exposure to light. The cationic photopolymerization initiator (B2) can contain at least one of an ionic photoacid-generating cationic curing catalyst and a nonionic photoacid-generating cationic curing catalyst.

[0195] The ionic photoacid-generating cationic curing catalyst can contain at least one of onium salts and organometallic complexes. Examples of onium salts include aromatic diazonium salts, aromatic halonium salts, and aromatic sulfonium salts. Examples of organometallic complexes include iron-arene complexes, titanocene complexes, and arylsilanol-aluminum complexes. The ionic photoacid-generating cationic curing catalyst can contain at least one of these components.

[0196] The nonionic photoacid-generating cationic curing catalyst may contain at least one component selected from the group consisting of, for example, nitrobenzyl esters, sulfonic acid derivatives, phosphate esters, phenolsulfonic acid esters, diazonaphthoquinones, and N-hydroxyimide phosphonates. However, the components that the nonionic photoacid-generating cationic curing catalyst may contain are not limited to those listed above.

[0197] More specific examples of compounds that can contain the photocationic polymerization initiator (B2) include Midori Chemical's DPI series (105, 106, 109, 201, etc.), BI-105, MPI series (103, 105, 106, 109, etc.), BBI series (101, 102, 103, 105, 106, 109, 110, 200, 210, 300, 301, etc.), and TSP series. Series (102, 103, 105, 106, 109, 200, 300, 1000, etc.), HDS-109, MDS series (103, 105, 109, 203, 205, 209, etc.), BDS-109, MNPS-109, DTS series (102, 103, 105, 200, etc.), NDS series (103, 105, 155, 165, etc.), DAM series (1 01, 102, 103, 105, 201, etc.), SI series (105, 106, etc.), PI-106, NDI series (105, 106, 109, 1001, 1004, etc.), PAI series (01, 101, 106, 1001, 1002, 1003, 1004, etc.), MBZ-101, PYR-100, NB series (101, 201, etc.), NAI series Series (100, 1002, 1003, 1004, 101, 105, 106, 109, etc.), TAZ series (100, 101, 102, 103, 104, 107, 108, 109, 110, 113, 114, 118, 122, 123, 203, 204, etc.), NBC-101, ANC-101, TPS-Acetate, DTS-Acetate, Di-Boc Bisphinol A, tert-Butyl lithocholate, tert-Butyl deoxycholate, tert-Butyl cholate, BX, BC-2, MPI-103, BDS-105, TPS-103, NAT-103, BMS-105, and TMS-105; Cyracure UVI-6970, Cyracure UVI-6974, Cyracure UVI-6990, and Cyracure UVI-950 manufactured by Union Carbide Corporation, USA; Irgacure 250, Irgacure 261 and Irgacure 264 manufactured by BASF; Ciba-Geigy CG-24-61; ADEKA Optomer SP-150, ADEKA Optomer SP-151, ADEKA Optomer SP-170 and ADEKA Optomer SP-171 manufactured by ADEKA Corporation; DAICAT II manufactured by Daicel Corporation; UVAC1590 and UVAC1591 manufactured by Daicel-Cytec Co., Ltd.; CI-2064, CI-2639, CI-2624, CI-2481, CI-2734, CI-2855, CI-2823, CI-2758, and CIT-1682 manufactured by Nippon Soda Co., Ltd.; PI-2074, tetrakis(pentafluorophenyl)borate toluylcumyl iodonium salt, from Rhodia; 3M FFC509; CD-1010, CD-1011 and CD-1012 manufactured by Sartomer, USA; San-Apro Co., Ltd. CPI-100P, CPI-101A, CPI-110P, CPI-110A, and CPI-210S; and UVI-6992 and UVI-6976 manufactured by The Dow Chemical Company are included. The cationic photopolymerization initiator (B2) may contain at least one compound selected from the group consisting of these compounds.

[0198] The ratio of the cationic photopolymerization initiator (B2) to the cationic polymerizable compound (W) is preferably within the range of 1 to 4% by mass. When this ratio is 1% by mass or more, the composition (X) can have particularly good cationic polymerization reactivity. When this ratio is 4% by mass or less, the composition (X) can have good storage stability, and the absence of excessive cationic photopolymerization initiator (B2) can reduce production costs.

[0199] The composition (X) may further contain a moisture absorbent (C). When the composition (X) contains the moisture absorbent (C), the cured product of the composition (X) and the encapsulant 5 can have moisture absorption properties. Therefore, the encapsulant 5 can further prevent moisture from penetrating into the light emitting element 4 in the light emitting device 1. The average particle size of the moisture absorbent (C) is preferably 200 nm or less. In this case, the cured product can have high transparency.

[0200] The moisture absorbent (C) is preferably inorganic particles having moisture absorption properties, and preferably contains at least one component selected from the group consisting of zeolite particles, silica gel particles, calcium chloride particles, and titanium oxide nanotube particles. It is particularly preferred that the moisture absorbent (C) contains zeolite particles.

[0201] Zeolite particles with an average particle size of 200 nm or less can be produced, for example, by pulverizing common industrial zeolite. To produce the zeolite particles, the zeolite may be pulverized and then crystallized by hydrothermal synthesis or the like. In this case, the zeolite particles can have particularly high hygroscopicity. Examples of methods for producing such zeolite particles are disclosed in JP 2016-69266 A, JP 2013-049602 A, and the like.

[0202] The zeolite particles preferably contain sodium ions. Therefore, the zeolite particles are preferably made from at least one type selected from the group consisting of A-type zeolite, X-type zeolite, and Y-type zeolite. It is particularly preferable that the zeolite particles be made from 4A-type zeolite, among A-type zeolites. In these cases, the zeolite particles have a crystalline structure suitable for adsorbing moisture.

[0203] The pH of the zeolite particles is preferably 7 or more and 10 or less. When the pH of the zeolite particles is 7 or more, the crystals of the zeolite particles are less likely to be destroyed, and therefore, a sealing material made from the composition (X) containing the zeolite particles can have particularly high moisture absorption. Furthermore, when the pH of the zeolite particles is 10 or less, the zeolite particles are less likely to inhibit the curing of the composition (X) when it is cured. The pH of the zeolite particles is a value obtained by heating a dispersion obtained by adding 0.05 g of zeolite particles to 99.95 g of ion-exchanged water at 90°C for 24 hours, and then measuring the pH of the supernatant of the dispersion with a pH meter. Examples of pH meter include a compact pH meter manufactured by Horiba, Ltd. <laquatwin>B-711 can be used.

[0204] The average particle size of the moisture absorbent (C) is preferably 10 nm or more and 200 nm or less. If this average particle size is 200 nm or less, the cured product can have particularly high transparency. Furthermore, if this average particle size is 10 nm or more, the moisture absorbent (C) can maintain good moisture absorption. Note that this average particle size is the median diameter calculated from the measurement results using dynamic light scattering, i.e., the cumulative 50% diameter (D50). Note that the Nanotrac Wave series from Microtrac Bell Co., Ltd. can be used as a measuring device.

[0205] The average particle size of the moisture absorbent (C) is preferably 150 nm or less, more preferably 100 nm or less, and particularly preferably 70 nm or less. The average particle size of the moisture absorbent (C) is preferably 20 nm or more, and more preferably 50 nm or more. In this case, the cured product can have particularly good transparency and moisture absorption.

[0206] It is also preferable that the cumulative 90% diameter (D90) of the moisture absorbent (C) is 100 nm or less, in which case the cured product can have particularly high transparency.

[0207] When composition (X) contains a moisture absorbent (C), the proportion of the moisture absorbent (C) relative to the total amount of composition (X) is preferably 1% by mass or more and 20% by mass or less. If the proportion of moisture absorbent (C) is 1% by mass or more, the cured product can have particularly high moisture absorption. Furthermore, if the proportion of moisture absorbent (C) is 20% by mass or less, the viscosity of composition (X) can be particularly reduced, and composition (X) can have a sufficiently low viscosity that it can be applied by an inkjet method. The proportion of moisture absorbent (C) is more preferably 3% by mass or more, and particularly preferably 5% by mass or more. Furthermore, the proportion of moisture absorbent (C) is more preferably 15% by mass or less, and particularly preferably 13% by mass or less.

[0208] The composition (X) may further contain an inorganic filler other than the moisture absorbent (C). In particular, the composition (X) preferably contains nano-sized high refractive index particles. Examples of high refractive index particles include zirconia particles. When the composition (X) contains high refractive index particles, the refractive index of the cured product can be increased while maintaining good transparency of the cured product. Therefore, when the cured product is used as the encapsulant 5 in the light-emitting device 1, the extraction efficiency of light that passes through the encapsulant 5 and is emitted to the outside can be improved. The average particle size of the high refractive index particles is preferably within a range of 5 to 30 nm, and more preferably within a range of 10 to 20 nm.

[0209] The proportion of high refractive index particles in the composition (X) is appropriately set so that the cured product has a desired refractive index. In particular, it is preferable that the high refractive index particles are contained in the composition (X) so that the refractive index of the cured product is in the range of 1.45 or more and less than 1.55. In this case, the light extraction efficiency of the light emitting device 1 is particularly improved.

[0210] When the composition (X) contains a moisture absorbent (C), the composition (X) preferably further contains a dispersant (D). In this case, the dispersant (D) can improve the dispersibility of the moisture absorbent (C) in the composition (X). Therefore, the composition (X) is less likely to experience an increase in viscosity and a decrease in storage stability due to the moisture absorbent (C).

[0211] The dispersant (D) is a surfactant capable of adsorbing to particles. The dispersant (D) has an adsorption group (commonly referred to as an anchor) capable of adsorbing to particles and a molecular skeleton (commonly referred to as a tail) that attaches to the particles when the adsorption group adsorbs to the particles. The dispersant (D) contains at least one component selected from the group consisting of, for example, an acrylic dispersant in which the tail is an acrylic molecular chain, a urethane dispersant in which the tail is a urethane molecular chain, and a polyester dispersant in which the tail is a polyester molecular chain. The adsorption group includes, for example, at least one of a basic polar functional group and an acidic polar functional group. The basic polar functional group includes, for example, at least one group selected from the group consisting of an amino group, an imino group, an amide group, an imide group, and a nitrogen-containing heterocyclic group. The acidic polar functional group includes, for example, at least one group selected from the group consisting of a carboxyl group and a phosphate group. The dispersant (D) may contain at least one compound selected from the group consisting of, for example, the Solsperse series manufactured by Nippon Louvre Resol Co., Ltd., the DISPERBYK series manufactured by BYK Japan Co., Ltd., and the Ajisper series manufactured by Ajinomoto Fine-Techno Co., Ltd.

[0212] When composition (X) contains moisture absorbent (C), the amount of dispersant (D) relative to the moisture absorbent (C) is preferably 5 parts by mass or more and 60 parts by mass or less. When the amount of dispersant (D) is 5 parts by mass or more, the function of dispersant (D) can be effectively exhibited, and when the amount is 60 parts by mass or less, free molecules of dispersant (D) in sealant 5 can be prevented from impairing the adhesion between sealant 5 and an inorganic material component. Furthermore, the amount of dispersant (D) is more preferably 15 parts by mass or more, more preferably 50 parts by mass or less, even more preferably 40 parts by mass or less, and particularly preferably 30 parts by mass or less.

[0213] The method for producing the composition (X) will be described.

[0214] First, a mixture (Y) is prepared. The mixture (Y) contains at least the photopolymerizable compound (A) and the photopolymerization initiator (B) among the components of the composition (X). The mixture (Y) may contain only the photopolymerizable compound (A) and the photopolymerization initiator (B). The mixture (Y) may also contain some or all of the remaining components of the composition (X) in addition to the photopolymerizable compound (A) and the photopolymerization initiator (B). That is, the mixture (X) may have the same composition as the composition (X) except that it has not been subjected to the deoxidation treatment described below.

[0215] It is preferable to subject the mixture (Y) to a deoxidizing treatment. This makes it easier to achieve a ratio of the composition (X) of 50 mg / L or less. The deoxidizing treatment is a treatment for removing oxygen from the mixture (Y) to reduce the oxygen content in the mixture (Y).

[0216] The specific content of the deoxidation treatment is not particularly limited. For example, the mixture (Y) can be deoxidized by exposing it to an atmosphere with an oxygen concentration lower than that of the atmosphere (hereinafter referred to as a low-oxygen atmosphere). In this case, the volume concentration of oxygen in the low-oxygen atmosphere is preferably 100 ppm or less. That is, it is preferable to expose the mixture (Y) to an atmosphere with a volume concentration of oxygen of 100 ppm or less. In this case, the proportion of dissolved oxygen in the composition (X) can be efficiently reduced. The volume concentration of oxygen in the low-oxygen atmosphere is more preferably 1% or less, and even more preferably 0.1% or less. The lower the volume concentration of oxygen in the low-oxygen atmosphere, the more preferable it is, and ideally 0 ppm. In the deoxidation treatment, the time for exposing the mixture (Y) to the low-oxygen atmosphere is preferably 1 hour or more. In this case, the proportion of dissolved oxygen in the composition (X) is particularly likely to be reduced. This time is, for example, 1 hour or more and 72 hours or less.

[0217] The proportion of dissolved oxygen in composition (X) can also be reduced by reducing the dissolved gas in mixture (Y) using a vacuum degassing apparatus. Oxygen can also be removed from mixture (Y) by exposing mixture (Y) to a stream of inert gas such as nitrogen gas. Oxygen can also be removed from mixture (Y) by blowing the inert gas into mixture (Y) to replace the oxygen in the mixture with the inert gas.

[0218] After deoxidizing the mixture (Y), the remaining components of the composition (X) can be added to the mixture (Y) as needed to prepare the composition (X). When the mixture (Y) contains all of the components of the composition (X), the mixture (Y) is deoxidized to prepare the composition (X). The composition (X) is preferably placed in a sealed container to prevent the composition (X) from absorbing oxygen during the period from the time of preparation to use.

[0219] The structure of the light emitting device 1 will be described. The light emitting device 1 includes a light source and an optical component that transmits light emitted by the light source. For example, the light emitting device 1 includes a light emitting element 4, and a sealant 5 and a passivation layer 6 that cover the light emitting element 4. In this case, the light emitting element 4 is the light source, the sealant 5 is the optical component, and the passivation layer 6 is an inorganic layer. The sealant 5 and the passivation layer 6 overlap each other.

[0220] 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. Note that EL is an abbreviation for electroluminescence.

[0221] An example of the structure of light-emitting device 1 will be described with reference to Fig. 1. This light-emitting device 1 is a top-emission type. Light-emitting device 1 includes a support substrate 2, a transparent substrate 3 facing the support substrate 2 with a gap therebetween, a light-emitting element 4 on the surface of 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.

[0222] The support substrate 2 is made of, for example, but not limited to, a resin material. The transparent substrate 3 is made of a light-transmitting material. 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, 43 and an organic light-emitting layer 42 between the electrodes 41, 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, which are stacked in the above order.

[0223] 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 element array 9) on a support substrate 2. The element array 9 also includes a partition wall 7. The partition wall 7 is located on the support substrate 2 and separates two adjacent light emitting elements 4. The partition wall 7 is fabricated, for example, by molding a photosensitive resin material using a photolithography method. The element array 9 also includes connection wiring 8 that electrically connects the electrodes 43 and the electron transport layers 424 of adjacent light emitting elements 4. The connection wiring 8 is provided on the partition wall 7.

[0224] The passivation layer 6 is preferably made of silicon nitride or silicon oxide, and particularly preferably made of silicon nitride. In the example shown in FIG. 1 , the passivation layer 6 includes a first passivation layer 61 and a second passivation layer 62. The first passivation layer 61 is in direct contact with the element array 9 and covers the element array 9, thereby covering the light-emitting elements 4. The second passivation layer 62 is disposed on the opposite side of the first passivation layer 61 from the element array 9, and a gap is provided between the second passivation layer 62 and the first passivation layer 61. An encapsulant 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 elements 4 and the encapsulant 5 covering the light-emitting elements 4.

[0225] Furthermore, 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 the sealing material 5.

[0226] A method for producing the encapsulant 5 using the composition (X) and a method for producing the light emitting device 1 will be described.

[0227] In this embodiment, it is preferable to produce the encapsulant 5 by molding the composition (X) by an inkjet method and then curing the composition (X) by irradiating it with ultraviolet light. In this embodiment, the composition (X) can be applied and molded by an inkjet method. In this embodiment, as described above, the oxygen content of the composition (X) is 75 mass % or less, and therefore defects are unlikely to occur when molding the composition (X) by an inkjet method.

[0228] When applying composition (X) by the inkjet method, if composition (X) has a sufficiently low viscosity at room temperature, for example, if the viscosity at 25°C is 20 mPa s or less, particularly 15 mPa s or less, composition (X) can be molded by applying it by the inkjet method without heating.

[0229] If composition (X) has the property of decreasing viscosity when heated, composition (X) may be heated and then applied by inkjet printing to form a mold. If composition (X) has a viscosity of 20 mPa·s or less, particularly 15 mPa·s or less at 40°C, composition (X) can be made to have a low viscosity by simply heating it slightly, and this low-viscosity composition (X) can be ejected by inkjet printing. The heating temperature for composition (X) is, for example, 20°C or higher and 50°C or lower.

[0230] More specifically, for example, first, a support substrate 2 is prepared. On one surface of this support substrate 2, partition walls 7 are fabricated by photolithography using, for example, a photosensitive resin material. 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 fabricated by an appropriate method such as a vapor deposition method or a coating method. In particular, it is preferable to fabricate the light-emitting elements 4 by a coating method such as an inkjet method. In this way, an element array 9 is fabricated on the support substrate 2.

[0231] Next, a first passivation layer 61 is provided on the element array 9. The first passivation layer 61 can be formed by a vapor deposition method such as a plasma CVD method.

[0232] Next, composition (X) is applied to the first passivation layer 61 by, for example, an inkjet method to form a coating film. If the inkjet method is used for both forming the light-emitting element 4 and applying composition (X), the manufacturing efficiency of the light-emitting device 1 can be particularly improved. Next, the coating film of composition (X) is cured by irradiating it with ultraviolet light to form the encapsulant 5. The thickness of the encapsulant 5 is, for example, 5 μm or more and 50 μm or less.

[0233] When irradiating composition (X) with ultraviolet light, the composition (X) may be irradiated with ultraviolet light in an oxygen-containing atmosphere, such as air, or in an inert atmosphere, such as a nitrogen atmosphere. In this embodiment, as described above, the oxygen content of composition (X) is 75 mass% or less, so oxygen inhibition is unlikely to occur, especially even when photopolymerizable compound (A) contains radically polymerizable compound (A1). Therefore, composition (X) can be easily cured even when irradiated with ultraviolet light in an oxygen-containing atmosphere.

[0234] Next, a second passivation layer 62 is provided on the sealing material 5. The second passivation layer 62 can be formed by a vapor deposition method such as a plasma CVD method.

[0235] Next, an ultraviolet-curable resin material is provided on one surface of the support substrate 2 so as to cover the second passivation layer 62, and then the transparent substrate 3 is placed on top of this resin material. The transparent substrate 3 is, for example, a glass substrate or a transparent resin substrate.

[0236] Next, ultraviolet light is irradiated from the outside toward the transparent substrate 3. The ultraviolet light passes through the transparent substrate 3 and reaches the ultraviolet-curable resin material, which then hardens, forming the second sealing member 52.

[0237] In this embodiment, as described above, it is possible to make it difficult for the light emitting efficiency to decrease due to the passivation layer 6 and the sealing material 5 in the light emitting device 1 to decrease.

[0238] The thickness of the sealing material 5 is, for example, 1 μm or more and 20 μm or less. The thickness of the sealing material 5 may be 15 μm or less. In this case, by thinning the sealing material 5, the light emitting device 1 can be thinned, and a flexible light emitting device 1 can be obtained. Furthermore, even if the thickness of the sealing material 5 is 10 μm or less, in this embodiment, a decrease in luminous efficiency caused by the passivation layer 6 and the sealing material 5 in the light emitting device 1 is unlikely to occur. It is more preferable that the thickness of the sealing material 5 is 8 μm or less. In order to effectively prevent moisture from entering the light emitting element 4 by the sealing material 5, the thickness of the sealing material 5 is preferably 3 μm or more, and more preferably 5 μm or more.

[0239] The thickness of the passivation layer 6 overlapping the sealing material 5 is, for example, not less than 0.1 μm and not more than 2 μm. When the passivation layer 6 includes the first passivation layer 61 and the second passivation layer 62 as described above, it is preferable that the thickness of each of the first passivation layer 61 and the second passivation layer 62 is not less than 0.1 μm and not more than 2 μm.

[0240] The use of the composition (X) according to this embodiment is not limited to the production of the encapsulant 5 for the light-emitting element 4. The composition (X) can be used to produce various optical components that transmit light emitted by a light source. For example, the optical component may be a color resist. That is, for example, a phosphor may be contained in the composition (X), and a color resist for a color filter may be produced from this composition (X). This color filter can be provided in a display device such as an organic EL display or a micro LED display, which is a light-emitting device. [Example]

[0241] 1. Preparation of the Composition Compositions of the examples and comparative examples were prepared by mixing the components shown in the table below.

[0242] The details of the components shown in the table are as follows. The viscosity of each component was measured using a rheometer (Anton Paar Japan, model number DHR-2) at a temperature of 25°C and a shear rate of 1000 s -1 The values ​​were measured under the following conditions. -ACMO: Acryloylmorpholine, boiling point 265°C, viscosity 12 mPa·s, glass transition temperature 145°C. -Morpholin-4-yl acrylate: boiling point 290°C, viscosity 16 mPa·s, glass transition temperature 115°C. -N-vinyl-ε-caprolactam: Manufactured by BASF, boiling point 245°C, viscosity 6 mPa·s, glass transition temperature 90°C. -Phenoxyethyl acrylate: Boiling point 290°C, viscosity 13 mPa·s, glass transition temperature 2°C. -3PG: Tris(propylene glycol) dimethacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., boiling point 400°C, viscosity 13 mPa·s. -APG200: Tris(propylene glycol) diacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., boiling point 295°C, viscosity 12 mPa·s. -3G: Triethylene glycol dimethacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., boiling point 290, viscosity 8 mPa·s. -BD: 1,4-butanediol dimethacrylate, manufactured by Shin-Nakamura Chemical Co., Ltd., boiling point 280, viscosity 7 mPa·s. -SR351S: Trimethylolpropane triacrylate, boiling point above 300°C, viscosity 106 mPa·s. -VEEA: 2-(2-vinyloxyethoxy)ethyl acrylate, boiling point 260°C, viscosity 4 mPa·s. - Irgacure 907: 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one manufactured by BASF. - Irgacure 819: BASF, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide. -Irgacure TPO: 2,4,6-trimethylbenzoyl-diphenylphosphine oxide manufactured by BASF.

[0243] 2.Evaluation Test The following evaluation tests were carried out on the examples and comparative examples, and the results are shown in the table below.

[0244] (1) Viscosity at 25℃ The viscosity of the composition was measured using a rheometer (Anton Paar Japan, model number DHR-2) at a temperature of 25°C and a shear rate of 1000 s -1 The measurement was carried out under the following conditions.

[0245] (2) 40℃ viscosity The viscosity of the composition was measured using a rheometer (Anton Paar Japan, model number DHR-2) at a temperature of 40°C and a shear rate of 1000 s -1 The measurement was carried out under the following conditions.

[0246] (3) Dissolved oxygen percentage The proportion of dissolved oxygen in the composition was measured in accordance with JIS K 0102. Specifically, an optical, solvent-resistant Visiferm dissolved oxygen concentration meter manufactured by Hamilton was used to measure the dissolved oxygen concentration of the ink composition.

[0247] (4) UV curing in atmospheric conditions (touch test) The composition was applied to form a coating film. The coating film was irradiated with ultraviolet light at an intensity of 5 W / cm using a Unijet E075IIHD (peak wavelength 395 nm) manufactured by Ushio Inc. in an air atmosphere. 2 , and the cumulative light intensity is 1500mJ / cm 2 The coating was photocured by irradiating it under the conditions of 0.5 W / cm 2 and a thickness of 10 μm. 2 , and the cumulative light intensity is 1500mJ / cm 2 When the temperature was changed to , a film was prepared in the same manner.

[0248] The film was subjected to a finger touch test, and the irradiation intensity was 5W / cm 2 and 0.5W / cm 2 When no tack was observed in any of the cases, it was designated as "A" and the irradiation intensity was 5W / cm 2 In the case of 0.5W / cm 2 In the case of , if no sticking was observed, it was marked "B", and the irradiation intensity was 5W / cm 2 and 0.5W / cm 2 When tack was observed in any of the above cases, the sample was evaluated as "C."

[0249] (5) UV curing in atmospheric conditions (pencil strength) The composition was applied to form a coating film. The coating film was irradiated with ultraviolet light at an intensity of 5 W / cm using a Unijet E075IIHD (peak wavelength 395 nm) manufactured by Ushio Inc. in an air atmosphere. 2 And the cumulative light intensity is 1500mJ / cm 2 The coating was photocured by irradiating under the conditions of

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[0250] (6) Glass transition temperature The composition was applied to form a coating film, and the coating film was irradiated with ultraviolet light at an intensity of 5 W / cm using a Unijet E075IIHD (peak wavelength 395 nm) manufactured by Ushio Inc. in an air atmosphere. 2 , and cumulative light intensity 5000mJ / cm 2 The coating was photocured by irradiating under the conditions of

[0043] , and a film with a thickness of 200 μm was produced. The glass transition temperature of a sample cut from this film was measured using a viscoelasticity measuring device (Hitachi High-Tech Science Corporation, Model No. DMA7100).

[0251] (7) Adhesion The composition was applied to a piece of quartz glass (dimensions: 50 mm x 25 mm x 1 mm) to prepare a coating film with a thickness of 50 μm. Another piece of quartz glass was placed on top of this coating film so that the dimensions of the contact area between the two were 12.5 mm x 25 mm. The composition was applied to a quartz glass piece in an air atmosphere using a Unijet E075IIHD (peak wavelength: 395 nm) manufactured by Ushio Inc., at an irradiation intensity of 5 W / cm. 2 , and an integrated light intensity of 3000mJ / cm 2 The composition was photocured by irradiating it with ultraviolet light under the conditions of

[0252] Next, the adhesive strength between the two quartz glass pieces was measured by a tensile shear test (tensile speed 5 mm / min) in accordance with JIS K 6850. The results were evaluated according to the following criteria. A: 15MPa or more. B: Less than 15 MPa.

[0253] (8) Outgassing evaluation The outgassing when the cured composition was heated was sampled by the headspace method and measured by gas chromatography. Specifically, 100 mg of the composition was placed in a 22 mL headspace vial. Next, the composition was irradiated with ultraviolet light at an intensity of 5 W / cm using a Unijet E075IIHD (peak wavelength 395 nm) manufactured by Ushio Inc. under atmospheric conditions. 2 , and the cumulative light intensity is 1500mJ / cm 2 The composition was cured by irradiating under the conditions of

[0043] , and then the vial was sealed. The composition was then heated at 80°C for 30 minutes, and the gas phase in the vial was then introduced into a gas chromatograph for analysis. The concentration of outgassing from the composition was determined based on the peak area of ​​the resulting gas chromatogram. The outgassing concentration is the volume fraction of outgassing in the gas phase of the vial relative to the vial's volume (22 mL).

[0254] The outgassing concentrations were determined using toluene as the reference substance. Specifically, two reference samples with toluene concentrations of 1000 ppm and 100 ppm were prepared by volatilizing toluene in a vial. Each reference sample was introduced into a gas chromatograph and analyzed. The relationship between peak area and concentration was determined from the peak areas of the two chromatograms obtained, and the outgassing concentrations were determined based on these results.

[0255] As a result, the outgassing concentration (volume fraction) was evaluated as "A" if it was 60 ppm or less, "B" if it was more than 60 ppm and 100 ppm or less, "C" if it was more than 100 ppm and 200 ppm or less, and "D" if it was more than 200 ppm.

[0256] (9) Inkjet compatibility The composition was placed in a cartridge of an inkjet printer (Fujifilm, Model DMP2831), and droplets of the composition were ejected from the nozzle of the inkjet printer at a temperature of 30°C and a frequency of 1 kHz. The droplets were observed with a high-speed camera, and were rated as "A" when neither mist nor satellites were observed, and "B" when at least one of mist or satellites was observed.

[0257] (10) Storage stability A test was conducted in which the composition was left to stand for two months at 60°C in a nitrogen atmosphere. The viscosity change rate Rμ was calculated using the viscosity μ0 of the composition before the test and the viscosity μ1 of the composition after the test using the following formula (M1). A rate of change of less than 10% was evaluated as "A," a rate of change of 10% or more but less than 20% was evaluated as "B," and a rate of change of 20% or more was evaluated as "C." Rμ={(μ1-μ0) / μ0}×100(%) …(M1)

[0258] [Table 1]

[0259] [Table 2]

[0260] [Table 3] < / laquatwin>

Claims

1. An ultraviolet-curable resin composition containing a photopolymerizable compound (A) and a photopolymerization initiator (B), The photopolymerizable compound (A) contains a radical polymerizable compound (A1), The radical polymerizable compound (A1) contains an acrylic compound (Y), the acrylic compound (Y) contains a compound having nitrogen in its molecular skeleton, and the compound having nitrogen in its molecular skeleton contains a compound having a morpholine skeleton; The acrylic compound (Y) further contains a polyfunctional acrylic compound (Y1) containing a compound (Y11) having a structure represented by the following formula (200): CH ２ =CR １ -COO-(R ３ -O)n-CO-CR ２ =CH ２ …(200) In formula (200), R １ and R ２ each is a hydrogen atom or a methyl group, n is an integer of 1 or more, R ３ is an alkylene group having 3 or more carbon atoms, and when n is 2 or more, there are multiple R ３ may be the same or different from each other, a ratio of the compound having a morpholine skeleton to the acrylic compound (Y) is 5% by mass or more and 50% by mass or less, the percentage of the compound (Y11) relative to the acrylic compound (Y) is 50% by mass or more and 95% by mass or less; a proportion of dissolved oxygen in the ultraviolet curable resin composition is 100 mg / L or less with respect to the ultraviolet curable resin composition; UV curable in the atmosphere. UV curable resin composition.

2. For producing an optical component that transmits light emitted by a light source, The ultraviolet-curable resin composition according to claim 1 .

3. Formed using the inkjet method, The ultraviolet-curable resin composition according to claim 1 or 2.

4. Contains no solvent or the solvent content is 1% by mass or less; The ultraviolet-curable resin composition according to claim 1 .

5. At least one of the viscosity at 25°C and the viscosity at 40°C is 30 mPa·s or less That is, The ultraviolet-curable resin composition according to claim 1 .

6. The glass transition temperature of the cured product is 80°C or higher. The ultraviolet-curable resin composition according to claim 1 .

7. The rate of outgassing generated when the cured product is heated at 80°C for 30 minutes is 500 ppm or less. The ultraviolet-curable resin composition according to claim 1 .

8. The acrylic compound (Y) contains a monofunctional acrylic compound (Y2), the ratio of the monofunctional acrylic compound (Y2) to the acrylic compound (Y) is more than 0 mass% and 20 mass% or less; The ultraviolet-curable resin composition according to claim 1 .

9. The photopolymerization initiator (B) contains a photopolymerization initiator having photobleaching properties. The ultraviolet-curable resin composition according to claim 1 .

10. The viscosity μ of the ultraviolet curable resin composition before the test was measured by leaving the composition at 60° C. for 2 months under a nitrogen atmosphere. 0 and the viscosity μ of the ultraviolet curable resin composition after the test 1 The viscosity change rate Rμ calculated from the following formula (M1) is less than 20%. Rμ={(μ 1 -μ 0 ) / μ 0 }×100(%) …(M1) The ultraviolet-curable resin composition according to claim 1 .

11. A cured product of the ultraviolet-curable resin composition according to any one of claims 1 to 10. Optical components.

12. A method for producing an optical component, comprising molding the ultraviolet-curable resin composition according to claim 1 by an inkjet method, and then curing the ultraviolet-curable resin composition by irradiating it with ultraviolet light.

13. Irradiating the ultraviolet-curable resin composition with ultraviolet light in an atmospheric environment. The method for manufacturing an optical component according to claim 12.

14. A light source and an optical component that transmits light emitted from the light source, wherein the optical component includes a cured product of the ultraviolet-curable resin composition according to any one of claims 1 to 10. Light-emitting device.

15. A method for manufacturing a light emitting device including a light source and an optical component that transmits light emitted by the light source, The optical component is manufactured by the method of claim 12 or 13. A method for manufacturing a light-emitting device.

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