Ultraviolet curable resin composition for sealing organic EL elements, organic EL light-emitting device, method for manufacturing the same, and touch panel

Abstract

An object of the present disclosure is to provide an ultraviolet curable resin composition for sealing an organic EL element, which can be formed by an inkjet method and is easily made to have a low relative dielectric constant of the cured product. The ultraviolet curable resin composition for sealing an organic EL element of the present disclosure contains an acrylic compound (A) and a photopolymerization initiator (B), and the relative dielectric constant of the cured product at a frequency of 100 kHz is 3.0 or less, and the ultraviolet curable resin composition for sealing an organic EL element is formed by an inkjet method.

Description

Technical Field

[0001] The present disclosure relates to an ultraviolet curable resin composition for sealing an organic EL element, a method for manufacturing an organic EL light-emitting device, an organic EL light-emitting device, and a touch panel. More specifically, the present disclosure relates to an ultraviolet curable resin composition for sealing an organic EL element, which is suitable as a sealing material for manufacturing an organic EL light-emitting device, a method for manufacturing an organic EL light-emitting device using the above composition, an organic EL light-emitting device including the above sealing material, and a touch panel including the above organic EL light-emitting device. Background Art

[0002] In a top-emission type organic EL light-emitting device, for example, an organic EL element is disposed on a support substrate, a transparent substrate is disposed opposite to the support substrate, and a transparent sealing material is filled between the support substrate and the transparent substrate. The sealing material is formed, for example, by an inkjet method.

[0003] Patent Document 1 shows an example of an ultraviolet curable resin composition formed by an inkjet method used in the production of a sealing material for an organic EL light-emitting device. Specifically, Patent Document 1 discloses an ink composition containing a polyethylene glycol di(meth)acrylate monomer, a mono(meth)acrylate monomer, a polyfunctional (meth)acrylate crosslinking agent, and a crosslinkable photopolymerization initiator.

[0004] In recent years, organic EL light-emitting devices have been applied to displays (touch panels) equipped with touch sensors. In a touch panel, for example, a touch sensor is disposed on a transparent substrate of an organic EL light-emitting device. When using the touch panel, malfunction of the touch sensor sometimes occurs. The inventors have found that a high dielectric constant of the sealing material causes the malfunction.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: WO 2017 / 39857 Summary of the Invention

[0008] An object of the present disclosure is to provide an ultraviolet curable resin composition for sealing an organic EL element that can be formed by an inkjet method and is easily made to have a low dielectric constant of a cured product, a method for manufacturing an organic EL light-emitting device, an organic EL light-emitting device, and a touch panel.

[0009] One embodiment of the ultraviolet curable resin composition for sealing an organic EL element of the present disclosure contains an acrylic compound (A) and a photopolymerization initiator (B). The relative dielectric constant of the cured product of the ultraviolet curable resin composition for sealing an organic EL element is 3.0 or less at a frequency of 100 kHz. The ultraviolet curable resin composition for sealing an organic EL element is formed by an inkjet method.

[0010] One embodiment of the method for manufacturing an organic EL light-emitting device of the present disclosure is a method for manufacturing an organic EL light-emitting device including an organic EL element and a sealing material covering the organic EL element. The method for manufacturing an organic EL light-emitting device includes: after forming the ultraviolet curable resin composition for sealing an organic EL element by an inkjet method, irradiating the ultraviolet curable resin composition for sealing an organic EL element with ultraviolet rays to cure it, thereby producing the sealing material.

[0011] One embodiment of the organic EL light-emitting device of the present disclosure includes an organic EL element and a sealing material covering the organic EL element, and the sealing material is a cured product of the ultraviolet curable resin composition for sealing an organic EL element.

[0012] One embodiment of the touch panel of the present disclosure includes the above organic EL light-emitting device and a touch sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A is a schematic cross-sectional view showing a first example of an organic EL light-emitting device according to an embodiment of the present disclosure. Figure 1 B is a schematic cross-sectional view showing a second example of the organic EL light-emitting device described above.

[0014] Figure 2 is a schematic cross-sectional view showing a touch panel according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0015] 1. Summary

[0016] One embodiment of the ultraviolet curable resin composition for sealing an organic EL element of the present disclosure (hereinafter, also referred to as resin composition (X)) contains an acrylic compound (A) and a photopolymerization initiator (B). The relative dielectric constant of the cured product of resin composition (X) is 3.0 or less at a frequency of 100 kHz. Resin composition (X) is formed by an inkjet method. By making the relative dielectric constant of the cured product of resin composition (X) 3.0 or less, the cured product of resin composition (X) can be made to have a low dielectric constant. Thereby, malfunction of the touch sensor including the sealing material formed of the cured product of resin composition (X) can be suppressed.

[0017] In this embodiment, the acrylic compound (A) preferably contains the compound (z), and the above compound (z) is at least one component selected from a compound having an isobornyl skeleton, a compound having a dicyclopentyl skeleton, and a compound having a 3,3,5-trimethylcyclohexyl skeleton. By including the compound (z) in the acrylic compound (A), it is easy to lower the dielectric constant of the cured product of the resin composition (X), that is, it is possible to lower the dielectric constant of the sealing material made of the resin composition (X). In addition, since the dielectric constant of the cured product can be lowered by the compound (z) in the acrylic compound (A), lowering the dielectric constant of the cured product can also prevent the viscosity of the resin composition (X) from increasing easily, and the resin composition (X) can be easily formed by the inkjet method.

[0018] 2. Details

[0019] Hereinafter, the organic EL light-emitting device 1, the manufacturing method of the organic EL light-emitting device 1, the touch panel 100, and the ultraviolet curable resin composition for sealing an organic EL element of this embodiment will be described in detail.

[0020] 2-1. Organic EL light-emitting device

[0021] Figure 1 The organic EL light-emitting device 1 of the first example shown in Figure 1 The organic EL light-emitting device 1 of the second example shown in B includes an organic EL element 4 and a sealing material 5 covering the organic EL element 4. The sealing material 5 is formed of the resin composition (X). The configurations of the organic EL light-emitting device 1 of the first example and the organic EL light-emitting device 1 of the second example will be described below.

[0022] (1) Organic EL light-emitting device of the first example

[0023] With reference to Figure 1 A, the configuration of the organic EL light-emitting device 1 of the first example will be described.

[0024] The organic EL light-emitting device 1 of the first example is a top-emission type. The organic EL light-emitting device 1 of the first example includes: a support substrate 2, a transparent substrate 3 disposed opposite to the support substrate 2 with a space therebetween, an organic EL element 4 located on the surface of the support substrate 2 opposite to the transparent substrate 3, and a sealing material 5 filled between the support substrate 2 and the transparent substrate 3. In addition, the organic EL light-emitting device 1 of the first example includes a passivation layer 6, and the above passivation layer 6 covers the surface of the support substrate 2 opposite to the transparent substrate 3 and the organic EL element 4.

[0025] The support substrate 2 is made of, for example, a resin material or glass, but the material of the support substrate 2 is not particularly limited. The support substrate 2 may be in a plate shape or a film shape.

[0026] The transparent substrate 3 is made of a light-transmissive material. The transparent substrate 3 is, for example, made of glass or transparent resin, but the material of the transparent substrate 3 is not particularly limited. The transparent substrate 3 can be in the form of a plate or a film.

[0027] The organic EL element 4 is also called an organic light-emitting diode. The organic EL element 4 includes, for example, a pair of electrodes and an organic light-emitting layer located between the electrodes.

[0028] The sealing material 5 is formed of a resin composition (X). The thickness of the sealing material 5 is, for example, 5 μm or more and 50 μm or less.

[0029] The passivation layer 6 is preferably made of silicon nitride or silicon oxide.

[0030] (2) Organic EL light-emitting device of the second example

[0031] Refer to Figure 1 Edge B will describe the configuration of the organic EL light-emitting device 1 of the second example. In Figure 1 B, for the elements that are the same as those in Figure 1 Example A shown in A, the same reference numerals as those in Figure 1 A are attached, and their detailed descriptions are appropriately omitted.

[0032] The organic EL light-emitting device 1 of the second example is also a top-emission type. The organic EL light-emitting device 1 of the second example includes: a support substrate 2, a transparent substrate 3 facing the support substrate 2 with a gap therebetween, an organic EL element 4 located on the surface of the support substrate 2 facing the transparent substrate 3, and a sealing material 5 covering the organic EL element 4. In addition, the organic EL light-emitting device 1 of the second example includes a passivation layer 6 covering the organic EL element 4.

[0033] The organic EL element 4 includes a pair of electrodes 41, 43 and an organic light-emitting layer 42 located between the electrodes 41, 43. The organic light-emitting layer 42 includes, for example, a hole injection layer 421, a hole transport layer 422, a light-emitting layer 423, and an electron transport layer 424, and these layers are stacked in the above order.

[0034] In the organic EL light-emitting device 1 of the second example, a plurality of organic EL elements 4 form an array 9 (hereinafter also referred to as an element array 9) on the support substrate 2. The element array 9 includes a partition wall 7. The partition wall 7 is located on the support substrate 2 and separates the space between two adjacent organic EL elements 4. The partition wall 7 is made, for example, by forming a photosensitive resin material by photolithography. The element array 9 further includes a connection wiring 8 that electrically connects the electrodes 43 and the electron transport layers 424 of adjacent organic EL elements 4 to each other. The connection wiring 8 is provided on the partition wall 7.

[0035] The passivation layer 6 includes a first passivation layer 61 and a second passivation layer 62. The first passivation layer 61 covers the element array 9 in a state of being in direct contact with the element array 9, thereby covering the organic EL element 4. The second passivation layer 62 is disposed on the side opposite to the element array 9 with respect to the first passivation layer 61, and there is a gap between the second passivation layer 62 and the first passivation layer 61.

[0036] A sealing material 5 is filled between the first passivation layer 61 and the second passivation layer 62. That is, the first passivation layer 61 is interposed between the organic EL element 4 and the sealing material 5 that covers the organic EL element 4. The sealing material 5 can be formed of a resin composition (X).

[0037] 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. There is no particular limitation on the material of the second sealing material 52. The material of the second sealing material 52 can be the same as or different from that of the sealing material 5.

[0038] 2-2. Manufacturing method of organic EL light-emitting device

[0039] As described above, the organic EL light-emitting device 1 includes an organic EL element 4 and a sealing material 5 formed of a resin composition (X). For example, the resin composition (X) can be formed by inkjet printing and then irradiated with ultraviolet rays to cure the resin composition (X), thereby manufacturing the sealing material 5.

[0040] In order to form the resin composition (X) by inkjet printing, the resin composition (X) preferably has a sufficiently low viscosity at normal temperature. Specifically, the viscosity of the resin composition (X) at 25°C is preferably 50 mPa·s or less. In this case, the resin composition (X) can be easily formed by inkjet printing.

[0041] (1) Manufacturing method of the organic EL light-emitting device of the first example

[0042] For Figure 1 the manufacturing method of the organic EL light-emitting device 1 of the first example shown in A is described.

[0043] First, a support substrate 2 is prepared.

[0044] Next, the organic EL element 4 is disposed on one surface of the support substrate 2. The organic EL element 4 can be manufactured by a coating method such as inkjet printing. The organic EL element 4 has Figure 1 the configuration of the first example shown in A.

[0045] Next, the passivation layer 6 is formed to cover one surface of the support substrate 2 and the organic EL element 4. The passivation layer 6 can be manufactured by, for example, evaporation.

[0046] Next, the resin composition (X) is formed by an inkjet method so as to cover one surface of the support substrate 2 and the organic EL element 4. In the present embodiment, the resin composition (X) is formed so as to cover the passivation layer 6. By performing both the formation of the organic EL element 4 and the coating of the resin composition (X) by the inkjet method, the manufacturing efficiency of the organic EL light-emitting device 1 can be improved.

[0047] Next, the transparent substrate 3 is overlapped on the formed resin composition (X).

[0048] Next, ultraviolet rays are irradiated on the transparent substrate 3 from the outside. The ultraviolet rays passing through the transparent substrate 3 reach the resin composition (X). By this ultraviolet ray, the radical polymerization reaction proceeds in the resin composition (X), and the resin composition (X) is cured, thereby producing the sealing material 5 formed of the cured product of the resin composition (X).

[0049] Through the above steps, the first example of the organic EL light-emitting device 1 can be manufactured.

[0050] (2) Manufacturing method of the second example of the organic EL light-emitting device

[0051] For Figure 1 the manufacturing method of the second example of the organic EL light-emitting device 1 shown in B will be described.

[0052] First, the support substrate 2 is prepared.

[0053] Next, the partition wall 7 is formed on one surface of the support substrate 2. The partition wall 7 can be formed, for example, by a photolithography method using a photosensitive resin material.

[0054] Next, a plurality of organic EL elements 4 are arranged on one surface of the support substrate 2. The plurality of organic EL elements 4 can be manufactured, for example, by an evaporation method or a coating method, and in the coating method, they can be manufactured by an inkjet method. An element array 9 is constituted by these plurality of organic EL elements 4.

[0055] Next, the first passivation layer 61 is arranged on the element array 9. The first passivation layer 61 can be formed, for example, by an evaporation method such as a plasma CVD method.

[0056] Next, a coating film of the resin composition (X) is formed on the first passivation layer 61. The coating film can be formed, for example, by an inkjet method. By performing both the formation of the organic EL element 4 and the coating of the resin composition (X) by the inkjet method, the manufacturing efficiency of the organic EL light-emitting device 1 can be improved. By irradiating ultraviolet rays on the coating film to cure it, the sealing material 5 formed of the cured product of the resin composition (X) can be produced.

[0057] Next, the second passivation layer 62 is arranged on the sealing material 5. The second passivation layer 62 can be formed, for example, by an evaporation method such as a plasma CVD method.

[0058] Next, after disposing a UV-curable resin material so as to cover the second passivation layer 62, the transparent substrate 3 is overlapped on the resin material.

[0059] Next, ultraviolet rays are irradiated onto the transparent substrate 3 from the outside. The ultraviolet rays passing through the transparent substrate 3 reach the UV-curable resin material. By this ultraviolet ray, the resin material is cured, and thus the second sealing material 52 formed of the cured product of the resin material is fabricated.

[0060] Through the above steps, the organic EL light-emitting device 1 of the second example shown in Figure 1 B can be manufactured.

[0061] 2-3. Touch Panel

[0062] With reference to Figure 2 the configuration of the touch panel 100 of the present embodiment will be described.

[0063] The touch panel 100 includes the organic EL light-emitting device 1 and the touch sensor 10. The organic EL light-emitting device 1 is, for example, a display device. The touch sensor 10 is disposed on the organic EL light-emitting device 1. The touch panel 100 further includes a polarizing plate 11 and a protective layer 12. In the touch panel 100, the organic EL light-emitting device 1, the touch sensor 10, the polarizing plate 11, and the protective layer 12 are laminated in this order.

[0064] The organic EL light-emitting device 1 is not particularly limited as long as it includes the sealing material 5 made of the resin composition (X). For example, the organic EL light-emitting device 1 may be the organic EL light-emitting device 1 of the first example described above, or may be the organic EL light-emitting device 1 of the second example described above. Figure 2 The touch panel 100 shown includes the organic EL light-emitting device 1 of the second example described above.

[0065] The touch sensor 10 is disposed on the organic EL light-emitting device 1. Therefore, the touch sensor 10 is disposed on the transparent substrate 3 included in the organic EL light-emitting device 1. The touch sensor 10 may be a capacitive type or a pressure-sensitive type. In the present embodiment, by making the resin composition (X) have a low dielectric constant, malfunction of the touch sensor 10 is easily suppressed. Especially when the touch sensor 10 is of the capacitive type, malfunction of the touch sensor 10 is easily suppressed.

[0066] The polarizing plate 11 is disposed on the touch sensor 10. By the polarizing plate 11, the visibility of the touch panel 100 can be improved. The polarizing plate 11 may be in a plate shape or a film shape. The polarizing plate 11 may be a known polarizing plate used in a display. The material of the polarizing plate 11 is not particularly limited, and is, for example, resin-made.

[0067] The protective layer 12 is disposed on the polarizing plate 11. The polarizing plate 11 can be protected through the protective layer 12. The protective layer 12 can be plate-shaped or film-shaped. The material of the protective layer 12 is not particularly limited, and for example, it is made of resin or glass.

[0068] The touch panel 100 can be manufactured, for example, by sequentially laminating a touch sensor 10, a polarizing plate 11, and a protective layer 12 on the organic EL light-emitting device 1.

[0069] 2-4. Ultraviolet curable resin composition for sealing organic EL elements

[0070] Details of the resin composition (X) of the present embodiment will be described.

[0071] The resin composition (X) contains an acrylic compound (A) and a photopolymerization initiator (B). In addition, the resin composition (X) may contain components other than the acrylic compound (A) and the photopolymerization initiator (B).

[0072] In the following description, “(meth)acrylic acid” is a general term for “acrylic acid” and “methacrylic acid”.

[0073] (1) Acrylic compound (A)

[0074] The acrylic compound (A) is a compound having a (meth)acryloyl group.

[0075] The acrylic compound (A) preferably contains a compound (z), and the above compound (z) is at least one component selected from a compound having an isobornyl skeleton, a compound having a dicyclopentyl skeleton, and a compound having a 3,3,5-trimethylcyclohexyl skeleton. Since the compounds having these skeletons have low polarity, by including the compound (z) in the resin composition (X), it is easy to make the cured product of the resin composition (X) have a low dielectric constant.

[0076] The compound having an isobornyl skeleton may contain, for example, one or more compounds selected from isobornyl acrylate and isobornyl methacrylate.

[0077] The compound having a dicyclopentyl skeleton may contain, for example, one or more compounds selected from dicyclopentyl acrylate, dicyclopentyl methacrylate, dicyclopentyl diacrylate, dicyclopentyl dimethacrylate, dicyclopentenyl acrylate, dicyclopentenyl oxyethyl acrylate, and dicyclopentenyl oxyethyl methacrylate. It should be noted that in this specification, the dicyclopentyl skeleton also includes the dicyclopentenyl skeleton.

[0078] Compounds having a 3,3,5-trimethylcyclohexyl skeleton may contain, for example, one or more compounds selected from 3,3,5-trimethylcyclohexyl acrylate and 3,3,5-trimethylcyclohexyl methacrylate.

[0079] Compound (z) may contain either or both of a monofunctional acrylic compound (z1) having only one (meth)acryloyl group in one molecule and a polyfunctional acrylic compound (z2) having a plurality of (meth)acryloyl groups in one molecule.

[0080] Among the monofunctional acrylic compounds (z1), compounds having a high glass transition temperature and a low viscosity are particularly preferred. By containing such a compound in the acrylic compound (A), it is easy to mold the resin composition (X) by an inkjet method. Examples of such compounds include isobornyl acrylate and dicyclopentanyl acrylate. That is, the acrylic compound (A) preferably contains either or both of isobornyl acrylate and dicyclopentanyl acrylate.

[0081] Among the polyfunctional acrylic compounds (z2), compounds having a low viscosity are particularly preferred. By containing such a compound in the acrylic compound (A), it is easy to mold the resin composition (X) by an inkjet method. Examples of such compounds include dicyclopentanyl diacrylate and dicyclopentanyl dimethacrylate. That is, the acrylic compound (A) preferably contains either or both of dicyclopentanyl diacrylate and dicyclopentanyl dimethacrylate.

[0082] The acrylic compound (A) may contain an acrylic compound (y) other than the compound (z). The acrylic compound (y) may contain either or both of a monofunctional acrylic compound (y1) having only one (meth)acryloyl group in one molecule and a polyfunctional acrylic compound (y2) having a plurality of (meth)acryloyl groups in one molecule.

[0083] The monofunctional acrylic compound (y1) contains, for example, at least one compound selected from dicyclopentenyl oxyethyl (meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, isooctyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, methoxytriethylene glycol (meth)acrylate, 2-ethoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, ethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, ethyl diethylene glycol (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, imide (meth)acrylate, isopentyl (meth)acrylate, ethoxylated succinic acid (meth)acrylate, trifluoroethyl (meth)acrylate, ω-carboxy polycaprolactone mono (meth)acrylate, cyclohexyl (meth)acrylate, 2-(2-ethoxyethoxy)ethyl (meth)acrylate, stearyl (meth)acrylate, diethylene glycol monobutyl ether (meth)acrylate, lauryl (meth)acrylate, isodecyl (meth)acrylate, isooctyl (meth)acrylate, octyl / decyl (meth)acrylate, tridecyl (meth)acrylate, caprolactone (meth)acrylate, ethoxylated (4) nonylphenol (meth)acrylate, methoxypolyethylene glycol (350) mono (meth)acrylate, methoxypolyethylene glycol (550) mono (meth)acrylate, phenoxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, benzyl (meth)acrylate, methylphenoxyethyl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, tribromophenyl (meth)acrylate, epoxidized tribromophenyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, ethylene oxide adduct of 2-phenoxyethyl (meth)acrylate, propylene oxide adduct of 2-phenoxyethyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 3-methacryloxymethyl cyclohexene oxide, and 3-(meth)acryloxymethyl cyclohexene oxide.

[0084] The monofunctional acrylic compound (y1) preferably contains a compound having an alicyclic structure. The compound having an alicyclic structure contains, for example, at least one compound selected from cyclohexyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, dicyclopentenyl oxyethyl (meth)acrylate, and 4-tert-butylcyclohexyl (meth)acrylate.

[0085] The monofunctional acrylic compound (y1) preferably also contains the compound (y11) represented by the following formula (10). In this case, it is easy to lower the viscosity of the resin composition (X), and it is easy to impart adhesiveness to the sealing material 5 made from the resin composition (X) with a member made of an inorganic material such as the passivation layer 6. In addition, although the compound (y11) has a low viscosity, it has the property of being less volatile. Therefore, even when the resin composition (X) is stored, the resin composition (X) is less likely to undergo a change in composition due to the volatilization of the monofunctional acrylic compound (y1).

[0086] [Chemical formula 1]

[0087]

[0088] In formula (10), R 0 is H or methyl. X is a single bond or a divalent hydrocarbon group. R 1 to R 11 are each H, an alkyl group, or -R 12 -OH, R 12 is an alkylene group, and at least one of R 1 to R 11 is an alkyl group or -R 12 -OH. R 1 to R 11 do not bond to each other chemically.

[0089] In formula (10), when X is a divalent hydrocarbon group, the carbon number of X is preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less. The divalent hydrocarbon group is, for example, a methylene group, an ethylene group, or a propylene group. X is particularly preferably a single bond or a methylene group. In this case, the compound (A31) has the advantages of a small molecular weight and a low viscosity.

[0090] In formula (10), when at least one of R 1 to R 11 is an alkyl group, the carbon number of the alkyl group is preferably 1 or more and 8 or less. The alkyl group is, for example, a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, or an octyl group. The alkyl group may be linear or may have a branched chain. That is, for example, when the alkyl group is a butyl group, the butyl group may be a tert-butyl group, a n-butyl group, or a sec-butyl group. When the alkyl group is a hexyl group, the hexyl group may be a tert-hexyl group, a n-hexyl group, or a sec-hexyl group. When the alkyl group is an octyl group, the octyl group may be, for example, a tert-octyl group. If the alkyl group is a methyl group or a tert-butyl group, it is particularly preferred. In this case, the compound (y11) has the advantages of a small molecular weight and a low viscosity.

[0091] In formula (10), it is preferred that only an alkyl group or -R 12 -OH is connected to the 4-position of the cyclohexane ring. That is, it is preferred that among R 1 to R 11 , R6 and R 7 one or both of which is an alkyl group or -R 12 -OH, and the rest are each H. Particularly preferably, among R 1 to R 11 only R 6 is an alkyl group or -R 12 -OH, and the rest are each H. In this case, the compound represented by the formula (10) can have good reactivity, and it is particularly easy to impart adhesiveness to the inorganic material-made member to the sealing material 5. It is considered that this is because the cyclohexane ring in the compound represented by the formula (10) has a boat-shaped conformation, and the large-sized alkyl group or -R 12 -OH located at the 4-position is likely to be in an approximately equatorial position. It is considered that by having such a structure in the compound represented by the formula (10), the reactivity of the (meth)acryloyl group in the compound represented by the formula (10) can be improved. In addition, when the compound represented by the formula (10) has such a structure, the free volume in the sealing material 5 can be increased by the compound represented by the formula (10). It is considered that, therefore, the interfacial free energy between the sealing material 5 and the inorganic material-made member is likely to become small, and thus the adhesiveness between the sealing material 5 and the inorganic material-made member is likely to be high. The larger the volume of the alkyl group or -R 12 -OH, the more likely the alkyl group or -R 12 -OH is to be in an approximately equatorial position. From this viewpoint, the larger the number of carbon atoms of the alkyl group or -R 12 -OH, the more preferable, and in addition, it is preferable that the alkyl group or -R 12 -OH has a branched chain. For example, it is preferable that the alkyl group or -R 12 -OH is a tert-butyl group.

[0092] In the formula (10), it is also preferable that only an alkyl group or -R 12 -OH is respectively connected to the 3-position and the 5-position of the cyclohexane ring. That is, it is preferable that among R 1 to R 11 , one or both of R 4 and R 5 are an alkyl group or -R 12 -OH, one or both of R 8 and R 9 are an alkyl group or -R 12 -OH, and the rest are each H. More preferably, among R 1 to R 11 , only one of R 4 and R 5 is an alkyl group or -R 12 -OH, one or both of R 8 and R 9 are an alkyl group or -R 12 -OH, and the rest are each H. Even more preferably, among R1 to R 11 Among them, R 4 and R 5 One or both of them are alkyl or -R 12 -OH, R 8 and R 9 Only one of them is alkyl or -R 12 -OH, and the rest are each H. In this case, the compound represented by the formula (10) can also have good reactivity, and it is particularly easy to impart adhesiveness to the inorganic material member to the sealing material 5. It is considered that this is because the cyclohexane ring in the compound represented by the formula (10) has a boat-shaped conformation, and the large-volume alkyl or -R 12 -OH at the 3-position and 5-position are each likely to be in an approximately equatorial position. It is considered that, therefore, similarly to the case where only an alkyl or -R 9 -OH is connected to the 4-position of the cyclohexane ring, the reactivity of the (meth)acryloyl group in the compound represented by the formula (10) is increased, and the adhesiveness between the sealing material 5 and the inorganic material member is easily increased. The larger the volume of the alkyl or -R 12 -OH, the more easily the alkyl or -R 12 -OH is in an approximately equatorial position. From this viewpoint, the larger the carbon number of the alkyl or -R 12 -OH, the more preferable, and in addition, it is preferable that the alkyl or -R 12 -OH has a branched chain. For example, it is preferable that the alkyl or -R 12 -OH is a tert-butyl group.

[0093] R 1 to R 11 When at least one of them is -R 12 -OH, the carbon number of R 12 is preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less. R 12 is, for example, methylene, ethylene or propylene. R 12 is particularly preferably methylene. In this case, the compound (y11) has the advantages of a small molecular weight and low viscosity.

[0094] In the formula (10), if R 1 to R 11 are each H or alkyl, and R 1 to R 11 At least one of them is alkyl, then it is particularly preferable. In this case, the compound represented by the formula (10) can have a particularly low viscosity, and thus the resin composition (X) can have a particularly low viscosity. Therefore, it is particularly easy to mold the resin composition (X) by an inkjet method.

[0095] The compound (y11) preferably contains at least one compound selected from the compounds represented by the following formula (11), the compounds represented by the following formula (12), and the compounds represented by the following formula (13).

[0096] [Chemical formula 2]

[0097]

[0098] The monofunctional acrylic compound (y1) is particularly preferably such that it contains one or both of the compounds represented by the formula (11) and the compounds represented by the formula (12). In this case, it is particularly easy to lower the viscosity of the resin composition (X), particularly easy to increase the glass transition temperature of the sealing material 5, and in addition, particularly easy to improve the adhesion between the sealing material 5 and the member made of an inorganic material. Further, the compounds represented by the formula (11) and the compounds represented by the formula (12) are not easily volatile, and thus it is easy to improve the storage stability of the resin composition (X).

[0099] The monofunctional acrylic compound (y1) also preferably contains a compound having a cyclic ether structure. The ring member number of the cyclic ether structure in the compound having a cyclic ether structure is preferably 3 or more, more preferably 3 or more and 4 or less. The number of carbon atoms contained in the cyclic ether structure is preferably 2 or more and 9 or less, more preferably 2 or more and 6 or less. The compound having a cyclic ether structure contains, for example, at least one compound selected from 3-methacryloxymethyl cyclohexene oxide and 3-acryloxymethyl cyclohexene oxide.

[0100] The monofunctional acrylic compound (y1) preferably contains at least one compound having a viscosity of 20 mPa·s or less at 25°C. In this case, the resin composition (X) can be made to have a low viscosity.

[0101] The monofunctional acrylic compound (y1) preferably contains at least one compound having a glass transition temperature of 80°C or higher. In this case, the cured product of the resin composition (X) can have a high glass transition temperature. The monofunctional acrylic compound (y1) more preferably contains at least one compound having a glass transition temperature of 90°C or higher, and further preferably contains at least one compound having a glass transition temperature of 100°C or higher.

[0102] The monofunctional acrylic compound (y1) preferably contains at least one compound having a boiling point of 200°C or higher. In this case, the monofunctional acrylic compound (y1) is not likely to reduce the storage stability of the resin composition (X). The monofunctional acrylic compound (y1) further preferably contains at least one compound having a boiling point of 250°C or higher.

[0103] The monofunctional acrylic compound (y1) particularly preferably contains at least one compound having a viscosity of 20 mPa·s or less at 25°C and a glass transition temperature of 80°C or higher. The monofunctional acrylic compound (y1) also preferably contains at least one compound having a viscosity of 20 mPa·s or less at 25°C and a boiling point of 200°C or higher. The monofunctional acrylic compound (y1) also preferably contains at least one compound having a glass transition temperature of 80°C or higher and a boiling point of 200°C or higher. The monofunctional acrylic compound (y1) particularly preferably contains at least one compound having a viscosity of 20 mPa·s or less at 25°C, a glass transition temperature of 80°C or higher, and a boiling point of 200°C or higher.

[0104] In particular, the monofunctional acrylic compound (y1) preferably contains at least one compound selected from dicyclopentenyl oxyethyl (meth)acrylate and 4-tert-butylcyclohexyl (meth)acrylate. Dicyclopentenyl oxyethyl (meth)acrylate and 4-tert-butylcyclohexyl (meth)acrylate have a high glass transition temperature, a low viscosity, and a high boiling point, and thus can particularly improve the properties of the resin composition (X), the curing agent, and the sealing material 5.

[0105] The polyfunctional acrylic compound (y2) may contain either or both of a compound (y20) having two (meth)acryloyl groups in one molecule and a compound (y21) having three or more (meth)acryloyl groups in one molecule.

[0106] The compound (y20) may contain, for example, at least one compound selected from 1,3-butanediol di(meth)acrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, triethylene glycol diacrylate, tripropylene glycol diacrylate, dipropylene glycol diacrylate, cyclohexanedimethanol diacrylate, tricyclodecane dimethanol diacrylate, bisphenol A polyethoxy diacrylate, bisphenol F polyethoxy diacrylate, propoxylated (2) neopentyl glycol diacrylate, 2-(2-ethoxyethoxy)ethyl acrylate, hexanediol diacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, 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, ethoxylated tripropylene glycol diacrylate, neopentyl glycol-modified trimethylolpropane diacrylate, stearic acid-modified pentaerythritol diacrylate, ethoxylated neopentyl glycol di(meth)acrylate, propoxylated neopentyl glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate.

[0107] The compound (y21) may contain, for example, at least one compound selected from 1,4-butanediol polyacrylate, 1,6-hexanediol polyacrylate, pentaerythritol tetraacrylate, trimethylolpropane triacrylate, tris(2-hydroxyethyl)isocyanurate triacrylate, pentaerythritol triacrylate, ethoxylated (3) trimethylolpropane triacrylate, propoxylated (3) glycerol triacrylate, pentaerythritol tetraacrylate, bis(trimethylolpropane) tetraacrylate, ethoxylated (4) pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, tripropylene glycol triacrylate, dipentaerythritol hexaacrylate, hydroxypivalic acid trimethylolpropane triacrylate, ethoxylated phosphoric acid triacrylate, tetramethylolpropane triacrylate, tetramethylolmethane triacrylate, caprolactone-modified trimethylolpropane triacrylate, propoxylated glycerol triacrylate, tetramethylolmethane tetraacrylate, ethoxylated pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, caprolactone-modified dipentaerythritol hexaacrylate, dipentaerythritol hydroxypentaacrylate, neopentyl glycol polyacrylate, trimethylolpropane polyacrylate, pentaerythritol polyacrylate, ethoxylated trimethylolpropane triacrylate, and propoxylated trimethylolpropane triacrylate.

[0108] Among the monofunctional acrylic compounds (y1), compounds with a high glass transition temperature and low viscosity are particularly preferred. By containing such a compound in the acrylic compound (A), the resin composition (X) can be easily formed by the inkjet method. As such a compound, 4-tert-butylcyclohexyl acrylate can be cited. That is, the acrylic compound (A) preferably contains 4-tert-butylcyclohexyl acrylate.

[0109] Among the polyfunctional acrylic compounds (y2), compounds with low viscosity are particularly preferred. By containing such a compound in the acrylic compound (A), the resin composition (X) can be easily formed by the inkjet method. As such a compound, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, pentaerythritol tetraacrylate, and trimethylolpropane triacrylate can be cited. That is, the acrylic compound (A) preferably contains one or more selected from polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, pentaerythritol tetraacrylate, and trimethylolpropane triacrylate.

[0110] The acrylic compound (A) may contain a crosslinking agent having a (meth)acrylate group. In this case, the cured product of the resin composition (X) can also have a low dielectric constant. In addition, the adhesion (adhesive force) of the resin composition (X) can be improved, and the glass transition temperature (Tg) of the resin composition (X) can be increased. The crosslinking agent having a (meth)acrylate group may contain, for example, one or more selected from alkyl (meth)acrylates, tricyclodecyl (meth)acrylates, fluorenyl (meth)acrylates, isocyanuric acid (meth)acrylates, and trimethylolpropane (meth)acrylates.

[0111] The acrylic compound (A) may contain an acrylic compound having a cationic polymerizable functional group. In this case, crosslinking is carried out by the acrylic compound having a cationic polymerizable functional group, and it is easy to ensure a high glass transition temperature of the cured product of the resin composition (X). Examples of the acrylic compound having a cationic polymerizable functional group include 3,4-epoxycyclohexylmethyl methacrylate, etc. As commercially available products of the acrylic compound having a cationic polymerizable functional group, for example, products named Cyclomer M100 manufactured by Daicel Corporation can be cited.

[0112] The acrylic compound (A) preferably contains a monofunctional acrylic compound (A1) having only one (meth)acryloyl group in one molecule, and the proportion of the monofunctional (meth)acrylic compound (A1) relative to the total amount of the acrylic compound (A) is 50% by mass or more. The monofunctional acrylic compound (A1) is a compound containing one or both of the monofunctional acrylic compound (z1) and the monofunctional acrylic compound (y1). That is, the acrylic compound (A) preferably contains one or both of the monofunctional acrylic compound (z1) and the monofunctional acrylic compound (y1), and the percentage of the total amount of the monofunctional acrylic compound (z1) and the monofunctional acrylic compound (y1) relative to the total amount of the acrylic compound (A) is 50% by mass or more. In this case, the amount of carbonyl groups in the resin composition (X) can be reduced, and the relative dielectric constant of the cured product of the resin composition (X) can be decreased. In addition, the proportion of the monofunctional (meth)acrylic compound (A1) relative to the total amount of the acrylic compound (A) is preferably 85% by mass or less, more preferably 80% by mass or less. In this case, the glass transition temperature of the cured product of the resin composition (X) can be increased.

[0113] In addition, the acrylic compound (A) may contain a polyfunctional acrylic compound (A2) having a plurality of (meth)acryloyl groups in one molecule. The polyfunctional acrylic compound (A2) is a compound containing one or both of the polyfunctional acrylic compound (z2) and the polyfunctional acrylic compound (y2).

[0114] The monofunctional acrylic compound (A1) preferably contains a compound (a1) having a methacryloyl group. The compound (a1) is a compound containing one or both of a compound having a methacryloyl group among the compounds classified as compound (z1) and a compound having a methacryloyl group among the compounds classified as compound (y1). That is, it is preferred that the compound (z) contains the compound (z1), and the compound (z1) contains a compound having a methacryloyl group. In addition, it is also preferred that the acrylic compound (A) contains the compound (y), the compound (y) contains the compound (y1), and the compound (y1) contains a compound having a methacryloyl group. The compound (a1) can contain, for example, one or more selected from isobornyl methacrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methacryloxymethylcyclohexene oxide, 3,3,5-trimethylcyclohexyl methacrylate, and 4-tert-butylcyclohexyl methacrylate. The percentage of the compound (a1) relative to the total amount of the acrylic compound (A) is preferably 25% by mass or more and 60% by mass or less. In this case, it is easy to lower the dielectric constant of the cured product of the resin composition (X). Thus, it is easy to lower the dielectric constant of the sealing material 5 made of the resin composition (X), and in a touch panel having an organic EL light-emitting device 1 including the sealing material 5, it is easy to suppress malfunction of the touch sensor.

[0115] (2) Photoinitiator (B)

[0116] The photoinitiator (B) preferably contains a radical polymerization initiator as a compound that generates radical species when irradiated with ultraviolet light. The photoinitiator (B) contains, for example, at least one compound selected from aromatic ketones, acylphosphine oxide compounds, α-hydroxyalkylbenzophenone compounds, aromatic onium salt compounds, organic peroxides, sulfur compounds (such as thioxanthone compounds and compounds containing a thiophenyl group), hexaarylbiimidazole compounds, ketoxime ester compounds, borate compounds, azinium compounds, metallocene compounds, active ester compounds, compounds having a carbon-halogen bond, and alkylamine compounds.

[0117] The photoinitiator (B) preferably contains an acylphosphine oxide compound. The photoinitiator (B) can contain, for example, one or both of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide and 2,4,6-trimethylbenzoyl-diphenylphosphinate. The photoinitiator (B) can contain a commercially available acylphosphine oxide compound. Examples of the commercially available acylphosphine oxide compound include Irgacure TPO, Irgacure TPO-L, and Irgacure 819 manufactured by BASF Corporation.

[0118] The photoinitiator (B) preferably contains an α-hydroxyalkyl phenyl ketone compound. The photoinitiator (B) may include one or more selected from 1-hydroxycyclohexyl phenyl ketone, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, and 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone. The photoinitiator (B) may contain a commercially available α-hydroxyalkyl phenyl ketone compound. Examples of the commercially available α-hydroxyalkyl phenyl ketone compound include Irgacure 184, Irgacure 907, Irgacure 369, and Irgacure 369E manufactured by BASF Corporation.

[0119] The photoinitiator (B) particularly preferably contains both an acylphosphine oxide compound and an α-hydroxyalkyl phenyl ketone. In this case, when the resin composition (X) is irradiated with ultraviolet rays, the resin composition (X) can be easily cured.

[0120] The photoinitiator (B) also preferably contains a component having photo-bleaching properties. The component having photo-bleaching properties preferably contains a compound having photo-bleaching properties among acylphosphine oxide compounds, and also preferably contains a compound having photo-bleaching properties among oxime ester compounds.

[0121] The photoinitiator (B) also preferably contains a component having a sensitizer skeleton in the molecule. The sensitizer skeleton includes, for example, one or both of a 9H-thioxanthen-9-one skeleton and an anthracene skeleton. That is, the photoinitiator (B) preferably contains a component having one or both of a 9H-thioxanthen-9-one skeleton and an anthracene skeleton.

[0122] From the viewpoints of improving the curability of the resin composition (X) and making it less likely for the cured product of the resin composition (X) to generate outgassing, the photoinitiator (B) preferably contains an oxime ester compound regardless of whether it has photo-bleaching properties or not.

[0123] In order to make it less likely for the resin composition (X) and the manufacturing apparatus to be contaminated by decomposition products generated from the resin composition (X), and in order to make it even less likely for the cured product to generate outgassing, the oxime ester compound preferably contains a compound having an aromatic ring, more preferably contains a condensed ring having an aromatic ring, and further preferably contains a condensed ring having a benzene ring and a heterocyclic ring.

[0124] Oxime ester compounds may contain, for example, at least one compound selected from 1,2-octanedione-1-[4-(phenylthio)-, 2-(o-benzoyl oxime)] and acetophenone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(o-acetyl oxime), and oxime ester compounds described in JP-A-2000-80068, JP-A-2001-233842, JP-T-2010-527339, JP-T-2010-527338, JP-A-2013-041153, and JP-A-2015-93842. Oxime ester compounds may contain at least one compound selected from commercially available Irgacure OXE-02 (manufactured by BASF), ADEKA ARKLS NCI-831, N-1919 (manufactured by ADEKA), and TR-PBG-304 (manufactured by Changzhou Qiangli Electronic New Materials Co., Ltd.) having a carbazole skeleton, Irgacure OXE-01, ADEKA ARKLS NCI-930 (manufactured by ADEKA), TR-PBG-345, and TR-PBG-3057 (the above are manufactured by Changzhou Qiangli Electronic New Materials Co., Ltd.) having a diphenyl sulfide skeleton, and TR-PBG-365 (manufactured by Changzhou Qiangli Electronic New Materials Co., Ltd.) and SPI-04 (manufactured by Sanyo) having a fluorene skeleton. In particular, when the oxime ester compound contains a compound having a diphenyl sulfide skeleton or a fluorene skeleton, it is preferable in terms of the cured product being less likely to be colored by photo-bleaching. The oxime ester compound containing a compound having a carbazole skeleton is also preferable in terms of easily improving the exposure sensitivity.

[0125] The oxime ester compound also preferably contains two or more compounds. In this case, for example, by the oxime ester compound containing two or more compounds having different exposure sensitivities, good exposure sensitivity can be maintained and the amount of the photopolymerization initiator (B) can be reduced, so that outgassing from the cured product of the resin composition (X) can be made less likely to occur.

[0126] With respect to 100 parts by mass of the resin composition (X), the proportion of the photopolymerization initiator (B) is, for example, 1 part by mass or more and 10 parts by mass or less. In this case, the resin composition (X) can be sufficiently cured.

[0127] The photoinitiator (B) may contain a sensitizer. The sensitizer can promote the radical generation reaction of the photoinitiator (B), improve the reactivity of radical polymerization, and increase the crosslinking density. The sensitizer may contain, for example, at least one compound selected from 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-dimethylaminobenzophenone, p-diethylaminobenzophenone, p-dimethylaminobenzaldehyde, and p-diethylaminobenzaldehyde.

[0128] When the photoinitiator (B) contains a sensitizer, for example, relative to 100 parts by mass of the solid content of the resin composition (X), the content of the sensitizer in the resin composition (X) is 0.1 part by mass or more and 5 parts by mass or less, preferably 0.1 part by mass or more and 3 parts by mass or less. In this case, the resin composition (X) can be cured in air, and the curing of the resin composition (X) does not need to be carried out in an inert atmosphere such as a nitrogen atmosphere.

[0129] (3) Components other than the acrylic compound (A) and the photoinitiator (B)

[0130] As described above, the resin composition (X) may contain components other than the acrylic compound (A) and the photoinitiator (B).

[0131] The resin composition (X) may contain, for example, a radically polymerizable compound (C) other than the acrylic compound (A). The radically polymerizable compound (C) may contain either or both of a polyfunctional radically polymerizable compound (C1) having two or more radically polymerizable functional groups in one molecule and a monofunctional radically polymerizable compound (C2) having only one radically polymerizable functional group in one molecule. The amount of the radically polymerizable compound (C) is, for example, 10% by mass or less relative to the total amount of the acrylic compound (A) and the radically polymerizable compound (C).

[0132] The polyfunctional radically polymerizable compound (C1) may contain, for example, at least one compound selected from aromatic carbamate oligomers, aliphatic carbamate oligomers, epoxy acrylate oligomers, polyester acrylate oligomers, and other special oligomers having two or more ethylenic double bonds in one molecule. More specifically, the polyfunctional radically polymerizable compound (C1) contains, for example, UV-2000B, UV-2750B, UV-3000B, UV-3010B, UV-3200B, UV-3300B, UV-3700B, UV-6640B, UV-8630B, UV-7000B, UV-7610B, UV-1700B, UV-7630B, UV-6300B, UV-6640B, UV-7550B, UV-7600B, UV-7605B, UV-7610B, UV-7630B, UV-7640B, UV-7650B, UT-5449, UT-5454 manufactured by Nippon Synthetic Chemical Industry Co., Ltd.;CN902, CN902J75, CN929, CN940, CN944, CN944B85, CN959, CN961E75, CN961H81, CN962, CN963, CN963A80, CN963B80, CN963E75, CN963E80, CN963J85, CN964, CN965, CN965A80, CN966, CN966A80, CN966B85, CN966H90, CN966J75, CN968, CN969, CN970, CN970A60, CN970E60, CN971, CN971A80, CN971J75, CN972, CN973, CN973A80, CN973H85, CN973J75, CN975, CN977, CN977C70, CN978, CN980, CN981, CN981A75, CN981B88, CN982, CN982A75, CN982B88, CN982E75, CN983, CN984, CN985, CN985B88, CN986, CN989, CN991, CN992, CN994, CN996, CN997, CN999, CN9001, CN9002, CN9004, CN9005, CN9006, CN9007, CN9008, CN9009, CN9010, CN9011, CN9013, CN9018, CN9019, CN9024, CN9025, CN9026, CN9028, CN9029, CN9030, CN9060, CN9165, CN9167, CN9178, CN9290, CN9782, CN9783, CN9788, CN9893; EBECRYL 210, EBECRYL 220, EBECRYL 230, EBECRYL 270, KRM 8200, EBECRYL 5129, EBECRYL 8210, EBECRYL 8301, EBECRYL 8804, EBECRYL 8807, EBECRYL 9260, KRM 7735, KRM 8296, KRM 8452, EBECRYL 4858, EBECRYL 8402, EBECRYL 9270, EBECRYL 8311, EBECRYL 8701 manufactured by Sartomer Company;At least one compound among B-1000, B-2000, and B-3000 manufactured by Nippon Soda Co., Ltd. When the resin composition (X) contains the polyfunctional radically polymerizable compound (C1), the polyfunctional radically polymerizable compound (C1) preferably contains B-1000 manufactured by Nippon Soda Co., Ltd. In this case, it is easy to make the resin composition (X) have a low dielectric constant.;

[0133] The monofunctional radically polymerizable compound (C2) may contain, for example, at least one compound selected from N-vinylformamide, vinylcaprolactam, vinylpyrrolidone, phenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, allyl glycidyl ether, 1,2-epoxybutane, 1,3-butadiene monooxide, 1,2-epoxydodecane, epichlorohydrin, 1,2-epoxydecane, styrene oxide, cyclohexene oxide, 3-vinylcyclohexene oxide, 4-vinylcyclohexene oxide, N-vinylpyrrolidone, and N-vinylcaprolactam.

[0134] The radically polymerizable compound (C) may contain one or more compounds (C3) selected from divinylbenzene, polybutadiene, and a compound having a (meth)acrylate group with divinylbenzene or polybutadiene as the basic skeleton. By including the compound (C3) in the resin composition (X), the cured product of the resin composition (X) can be made to have a low dielectric constant. However, when the molecular weight of the compound (C3) is large, the viscosity of the resin composition (X) tends to become high, and when the molecular weight of the compound (C) is small, the volatility tends to become high. Therefore, in order to make the cured product of the resin composition (X) have a low dielectric constant and make the resin composition (X) have a low viscosity, it is more preferable that the resin composition (X) contains the compound (z).

[0135] The resin composition (X) may contain a polymerization promoter (D). The polymerization promoter (D) can promote the radical polymerization reaction of the resin composition (X). The polymerization promoter (D) may contain, for example, one or more components selected from ethyl p-dimethylaminobenzoate, 2-ethylhexyl p-dimethylaminobenzoate, methyl p-dimethylaminobenzoate, 2-dimethylaminoethyl benzoate, and butoxyethyl p-dimethylaminobenzoate.

[0136] The resin composition (X) may contain a moisture absorbent (E). The moisture absorbent (E) can impart moisture absorbency to the cured product of the resin composition (X). The moisture absorbent (E) is preferably inorganic particles having moisture absorbency. The moisture absorbent (E) may contain, for example, one or more components selected from zeolite particles, silica gel particles, calcium chloride particles, and titanium oxide nanotube particles. The moisture absorbent (E) preferably contains zeolite particles, and particularly preferably contains zeolite particles having an average particle size of 200 nm or less. Such zeolite particles preferably contain sodium ions. For this purpose, the zeolite particles are preferably produced from zeolites containing sodium ions, and more preferably produced from at least one material selected from zeolite A, zeolite X, and zeolite Y in sodium zeolites. The zeolite particles are particularly preferably produced from zeolite 4A in zeolite A. In these cases, the zeolite particles have a crystal structure suitable for adsorbing moisture. The proportion of the moisture absorbent (E) relative to the total amount of the resin composition (X) is preferably 1% by mass or more and 20% by mass or less. When the proportion of the moisture absorbent (E) is 1% by mass or more, the cured product of the resin composition (X) can have high moisture absorbency. When the proportion of the moisture absorbent (E) is 20% by mass or less, the viscosity of the resin composition (X) can be reduced, and the resin composition (X) can be easily formed by an inkjet method.

[0137] The resin composition (X) may contain an inorganic filler (F). For example, the resin composition (X) may contain nano-sized high refractive index particles as the inorganic filler (F). In this case, good transparency of the cured product of the resin composition (X) can be maintained while making the cured product have a high refractive index. Therefore, when producing the sealing material 5 from the resin composition (X), the extraction efficiency of the light emitted to the outside through the sealing material 5 can be improved. The nano-sized high refractive index particles are, for example, zirconia particles.

[0138] When the resin composition (X) contains the moisture absorbent (E), the resin composition (X) may contain a dispersant (G). The dispersant (G) is a surfactant that can be adsorbed on the surface of the moisture absorbent (E). The dispersant (G) has, for example, an adsorption group capable of adsorbing on the particles of the moisture absorbent (E) and a tail, and the above-mentioned tail is a chain-like or comb-like molecular skeleton that is attached to the particles of the moisture absorbent (E) by adsorbing on the particles of the moisture absorbent (E) through the adsorption group. The dispersant (G) may contain, for example, one or more components selected from an acrylic dispersant having an acrylic molecular chain as the tail, a urethane dispersant having a urethane molecular chain as the tail, and a polyester dispersant having a polyester molecular chain as the tail. The dispersant (G) can disperse the moisture absorbent (E) well in the resin composition (X) and the cured product. Thereby, even if the cured product of the resin composition (X) contains the moisture absorbent (E), it is possible to suppress the decrease in the transparency of the cured product due to the moisture absorbent (E). In addition, the dispersant (G) can suppress the aggregation of the moisture absorbent (E) during the storage of the resin composition (X). Therefore, it is possible to prevent the storage stability of the resin composition (X) from being reduced due to the moisture absorbent (E). In addition, it is possible to suppress the decrease in the adhesion between the cured product of the resin composition (X) and silicon nitride and silicon oxide due to the dispersant (G). It is considered that this is because the dispersant (G) is easily adsorbed on the moisture absorbent (E) and is less likely to affect the interface between the cured product and silicon nitride and silicon oxide. Therefore, when the resin composition (X) contains the dispersant (G), the sealing material 5 can have high adhesion to the glass substrate. In addition, the adhesion between the passivation layer 6 made of silicon nitride or silicon oxide and the sealing material 5 can be improved. The ratio of the dispersant (G) to 100 parts by mass of the moisture absorbent (E) is preferably 5% by mass or more and 60% by mass or less. If the amount of the dispersant (G) is 5% by mass or more, the advantages of the dispersant (G) can be particularly exerted. If the amount of the dispersant (G) is 60% by mass or less, the adhesion between the cured product of the resin composition (X) and silicon nitride and silicon oxide can be improved.

[0139] The resin composition (X) may contain a cationically polymerizable compound (H). The cationically polymerizable compound (H) may include one or both of a monofunctional cationically polymerizable compound and a polyfunctional cationically polymerizable compound. The cationically polymerizable compound (H) preferably contains one or more compounds selected from alkyl-type epoxy compounds, dicyclopentadiene-type epoxy compounds, bisphenol F-type epoxy compounds, bisphenol A-type epoxy compounds, phenol novolac-type epoxy compounds, naphthalene-type epoxy compounds, oxetane compounds, and biphenyl-type epoxy compounds. These compounds can lower the dielectric constant of the cured product of the resin composition (X). It should be noted that in order to more easily lower the dielectric constant of the cured product of the resin composition (X), it is more preferable that the resin composition (X) contains the compound (z). As a particularly preferred cationically polymerizable compound (H), for example, 2-(4,4-dimethylpentan-2-yl)-5,7,7-trimethyloctanoic acid 2,3-epoxypropyl ester, (3,3',4,4'-diepoxy)bicyclohexane, 3-ethyl-3-{[(3-ethyloxetan-3-yl)methoxy]methyl}oxetane, etc. can be cited.

[0140] When the resin composition (X) contains a cationically polymerizable compound (H), the photoinitiator (B) preferably contains a cationic polymerization initiator (h). The cationic polymerization initiator (h) 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 polymerization initiator (h) may include one or both of an ionic photoacid-generating type cationic curing catalyst and a non-ionic photoacid-generating agent cationic curing catalyst. As a commercially available cationic polymerization initiator (h), for example, the type DTS-200 manufactured by Midori Chemical Co., Ltd. can be cited.

[0141] In the present embodiment, as described above, by including the compound (z) in the resin composition (X), the dielectric constant of the cured product of the resin composition (X) can be lowered. Therefore, in order to reduce the relative dielectric constant of the cured product of the resin composition (X), an inorganic filler (F) may not be blended in the resin composition (X). That is, the resin composition (X) may not contain an inorganic filler (F). In addition, when the resin composition (X) contains a moisture absorbent (E), an inorganic filler (F), and a dispersant (G), the viscosity of the resin composition (X) tends to increase, and sometimes it is difficult to mold the resin composition (X) by an inkjet method. Therefore, the resin composition (X) may not contain a moisture absorbent (E), an inorganic filler (F), and a dispersant (G).

[0142] Compound (z), which is at least one component selected from compounds having an isobornyl skeleton, compounds having a dicyclopentyl skeleton, and compounds having a 3,3,5-trimethylcyclohexyl skeleton, is less likely to increase the viscosity of the resin composition (X). Therefore, by containing compound (z) in the acrylic compound (A), even if the resin composition (X) does not contain a solvent, the resin composition (X) can be made to have a low viscosity, and the inkjet method can be applied in the molding of the resin composition (X). Therefore, it is also preferable that the resin composition (X) does not contain a solvent. In this case, when producing a cured product from the resin composition (X), it is not necessary to dry the resin composition (X) to volatilize the solvent. In addition, the storage stability of the resin composition (X) can be improved, and the generation of outgassing derived from the solvent can be suppressed. In addition, when the resin composition (X) contains a solvent, the proportion of the solvent relative to the resin composition (X) is preferably 1.0% by mass or less. The proportion of the solvent is more preferably 0.5% by mass or less, further preferably 0.3% by mass or less, and particularly preferably 0.1% by mass or less. The resin composition (X) is particularly preferably free of solvent or contains only an unavoidably incorporated solvent.

[0143] (4) Method for producing an ultraviolet-curable resin composition for sealing an organic EL element

[0144] The resin composition (X) can be prepared by mixing the above-mentioned acrylic compound (A), a photopolymerization initiator (B), and, if necessary, components other than the acrylic compound (A) and the photopolymerization initiator (B).

[0145] (5) Properties of the ultraviolet-curable resin composition for sealing an organic EL element

[0146] The viscosity of the resin composition (X) at 25°C is preferably 50 mPa·s or less. In this case, the resin composition (X) can be molded more favorably by the inkjet method. The viscosity of the resin composition (X) at 25°C is more preferably 30 mPa·s or less, further preferably 25 mPa·s or less, particularly preferably 20 mPa·s or less, and most preferably 15 mPa·s or less. The viscosity of the resin composition (X) at 25°C is preferably 1 mPa·s or more, and more preferably 5 mPa·s or more.

[0147] The viscosity of the resin composition (X) at 40°C is also preferably 50 mPa·s or less. In this case, regardless of the viscosity of the resin composition (X) at normal temperature, as long as the resin composition (X) is slightly heated, its viscosity can be lowered. Therefore, if heated, the resin composition (X) can be more favorably formed by the inkjet method. In addition, it is possible to lower the viscosity of the resin composition (X) without significantly heating it, so that changes in the composition of the resin composition (X) caused by the volatilization of the components in the resin composition (X) are less likely to occur. The viscosity of the resin composition (X) at 40°C is more preferably 30 mPa·s or less, further preferably 25 mPa·s or less, particularly preferably 20 mPa·s or less, and most preferably 15 mPa·s or less. The viscosity of the resin composition (X) at 25°C is preferably 1 mPa·s or more, and more preferably 5 mPa·s or more.

[0148] It should be noted that the viscosity of the resin composition (X) is measured using a rheometer under the condition of a shear rate of 100 s -1 . As the rheometer, for example, the model DHR-2 manufactured by Anton Paar Japan can be used.

[0149] The relative dielectric constant of the cured product of the resin composition (X) at a frequency of 100 kHz is 3.0 or less. Thereby, when the organic EL light-emitting device 1 including the sealing material 5 formed of the resin composition (X) is applied to the touch panel 100, it is easy to suppress malfunction of the touch sensor 10. The relative dielectric constant of the cured product of the resin composition (X) at a frequency of 100 kHz is more preferably 2.8 or less, and particularly preferably 2.7 or less.

[0150] In the present embodiment, the acrylic compound (A) contains a compound (z) which is at least one component selected from a compound having an isobornyl skeleton, a compound having a dicyclopentyl skeleton, and a compound having a 3,3,5-trimethylcyclohexyl skeleton. Thereby, the cured product of the resin composition (X) can be made to have a low dielectric constant. In addition, the compound (z) is less likely to increase the viscosity of the acrylic compound (A). Therefore, even if the resin composition (X) does not contain a solvent, the viscosity of the resin composition (X) can be lowered. However, as long as the relative dielectric constant of the cured product of the resin composition (X) can be 3.0 or less, the resin composition (X) is not limited to the acrylic compound (A) containing the compound (z).

[0151] The cured product of the resin composition (X) preferably has a glass transition temperature of 90 °C or higher. That is, the glass transition temperature of the cured product of the resin composition (X) and the glass transition temperature of the sealing material 5 formed from the resin composition (X) are preferably 90 °C or higher. In this case, the heat resistance of the sealing material 5 formed from the resin composition (X) can be improved. Therefore, when the organic EL light-emitting device 1 is subjected to a treatment at a high temperature, it is easy to suppress the deterioration of the sealing material 5. The glass transition temperature of the cured product of the resin composition (X) is more preferably 100 °C or higher. When the resin composition (X) contains a polyfunctional acrylic compound (A3), the molecular structure of the cured product of the resin composition (X) is easily three-dimensionalized, and it is easy to increase the glass transition temperature of the cured product.

[0152] Examples

[0153] Specific examples are given below. However, it is not limited to these examples.

[0154] 1. Preparation of the composition

[0155] Mix the components shown in the following table to prepare the resin compositions of the examples and comparative examples. It should be noted that the details of the components shown in the table are as follows.

[0156] · SR295NS: Pentaerythritol tetraacrylate manufactured by Sartomer, viscosity at 25 °C is 350 mPa·s. Glass transition temperature is 103 °C.

[0157] · SR351S: Trimethylolpropane triacrylate manufactured by Sartomer, viscosity at 25 °C is 106 mPa·S.

[0158] · SR506NS: Isobornyl acrylate manufactured by Sartomer, viscosity at 25 °C is 8 mPa·s, glass transition temperature is 97 °C.

[0159] · SR423NS: Isobornyl methacrylate manufactured by Sartomer, viscosity at 25 °C is 11 mPa·s, glass transition temperature is 110 °C.

[0160] · FA513AS: Dicyclopentyl acrylate manufactured by Hitachi Chemical, viscosity at 25 °C is 13 mPa·s, glass transition temperature is 120 °C.

[0161] · CD535: Dicyclopentyl methacrylate manufactured by Sartomer, viscosity at 25 °C is 17 mPa·s, glass transition temperature is 91 °C.

[0162] · CD420: 3,3,5-Trimethylcyclohexyl acrylate manufactured by Sartomer, viscosity at 25 °C is 6 mPa·s, glass transition temperature is 29 degrees.

[0163] · CD421: 3,3,5-Trimethylcyclohexyl methacrylate manufactured by Sartomer, viscosity at 25°C is 6 mPa·s, glass transition temperature is 145°C.

[0164] · TBCHA: 4-tert-Butylcyclohexyl acrylate manufactured by KJ Chemical, viscosity at 25°C is 7 mPa·s, glass transition temperature is 77°C.

[0165] · SR833S: Dicyclopentyl dimethacrylate manufactured by Sartomer, viscosity at 25°C is 110 mPa·S, glass transition temperature is 214°C.

[0166] · PEGDMA: Polyethylene glycol 200 dimethacrylate, manufactured by Shin-Nakamura Chemical Industry Co., Ltd., viscosity at 25°C is 14 mPa·s, glass transition temperature is 41°C.

[0167] · PEGDA: Polyethylene glycol 200 diacrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd., viscosity at 25°C is 17 mPa·s, glass transition temperature is 41°C.

[0168] · Cyclomer M100: 3,4-Epoxycyclohexylmethyl methacrylate, manufactured by Daicel Corporation, viscosity at 25°C is 9 mPa·s.

[0169] · B1000: 1,2-Polybutadiene homopolymer, manufactured by Nippon Soda Co., Ltd., viscosity at 25°C is 2000 mPa·s.

[0170] · FOLDI E101: 2-(4,4-Dimethylpentan-2-yl)-5,7,7-trimethyloctanoic acid 2,3-epoxypropyl ester, manufactured by Nissan Chemical Industries, Ltd., viscosity at 25°C is 40 mPa·s.

[0171] · Celloxide 8010: (3,3',4,4'-Diepoxy)bicyclohexane, manufactured by Daicel Corporation, viscosity at 25°C is 80 mPa·s.

[0172] · OXT221: 3-Ethyl-3-{[(3-ethyloxetan-3-yl)methoxy]methyl}oxetane, manufactured by Toagosei Co., Ltd., viscosity at 25°C is 10 mPa·s.

[0173] · 184: 1-Hydroxy-cyclohexyl-phenyl-ketone, manufactured by BASF, trade name Irgacure 184.

[0174] · TPO: 2,4,6-Trimethylbenzoyl-diphenyl-phosphine oxide, manufactured by BASF, trade name IrgacureTPO.

[0175] ·DTS-200: Manufactured by Midori Chemical, model DTS-200, C6H5-S-C6H4-S+(C6H5)2·B(C6F5)4.

[0176] 2. Evaluation Tests

[0177] The following evaluation tests were conducted on the examples and comparative examples. The results are shown in the table.

[0178] (1) Viscosity

[0179] The viscosity of the resin composition was measured using a rheometer (manufactured by Anton Paar Japan, model DHR-2) at a temperature of 25°C and a shear rate of 1000 s -1 under the condition of.

[0180] (2) Glass Transition Temperature of the Cured Product

[0181] A coating film was made by coating the resin composition, and using an LED-UV irradiator (peak wavelength 365 nm) manufactured by Panasonic Electric Works Co., Ltd., the coating film was irradiated with ultraviolet rays for 15 seconds under the condition of about 100 mW / cm 2 to cure it by light, and a film with a thickness of 100 μm was made.

[0182] Using a viscoelastic spectrometer "DMS 6100" manufactured by Seiko Instruments Inc., the glass transition temperature of the film obtained above was measured. At this time, the frequency was set to 10 Hz using a tensile module for dynamic viscoelasticity measurement (DMA), and the temperature at which tanδ showed a maximum when heating from room temperature to 200°C at a heating rate of 5°C / minute was taken as the glass transition temperature.

[0183] (3) Inkjetting Property

[0184] The resin composition was placed in the processing cartridge of an inkjet printer (manufactured by Ricoh, "MH2420"). After confirming that the resin composition in the processing cartridge could be discharged from the nozzles of the inkjet printer, the resin composition was discharged from the nozzles to continuously print a test pattern. As a result, when the resin composition could be discharged for 1 hour and the discharging operation was stable, it was evaluated as "A"; when the resin composition could be discharged for 1 hour but the discharging operation was intermittently unstable, it was evaluated as "B"; when the nozzles were clogged and the resin composition could not be discharged before 1 hour had passed since the start of discharging, it was evaluated as "C".

[0185] (4) Relative Dielectric Constant

[0186] A coating film of the resin composition with a thickness of 10 μm was made on an aluminum substrate having dimensions of 80 mm × 40 mm × 1 mm t. At 100 mW / cm 2Under the condition of , irradiate the coating film with ultraviolet rays for 15 seconds to cure the coating film. Use an LCR meter (manufactured by Agilent, "E4980A") and a fixture (16034 test fixture), and measure the relative dielectric constant of the cured coating film under the condition of a frequency of 100 kHz by the electrode contact method.

[0187] [Table 1]

[0188]

[0189] [Table 2]

[0190]

[0191] Explanation of reference numerals

[0192] 1: Organic EL light-emitting device;

[0193] 4: Organic EL element;

[0194] 5: Sealing material;

[0195] 10: Touch sensor;

[0196] 100: Touch panel.

Claims

1. An ultraviolet curable resin composition for sealing an organic EL element, which contains an acrylic compound A and a photoinitiator B, The acrylic compound A contains a monofunctional methacrylate a1 having only one methacryloyl group in one molecule, The proportion of the monofunctional methacrylate a1 relative to the total amount of the acrylic compound A is 25% by mass or more and 60% by mass or less, The relative dielectric constant of the cured product at a frequency of 100 kHz is 3.0 or less, The cured product has a glass transition temperature of 90 °C or higher, The ultraviolet curable resin composition for sealing an organic EL element is formed by an inkjet method.

2. The ultraviolet curable resin composition for sealing an organic EL element according to claim 1, wherein, The monofunctional methacrylate a1 contains a compound having a methacryloyl group, and the compound is at least one component selected from a compound having an isobornyl skeleton, a compound having a dicyclopentyl skeleton, and a compound having a 3,3,5-trimethylcyclohexyl skeleton.

3. The ultraviolet curable resin composition for sealing an organic EL element according to claim 1 or 2, wherein, The acrylic compound A contains a monofunctional (meth)acrylic compound A1 having only one (meth)acryloyl group in one molecule, and the monofunctional (meth)acrylic compound A1 contains the monofunctional methacrylate a1, The proportion of the monofunctional (meth)acrylic compound A1 relative to the total amount of the acrylic compound A is 50% by mass or more.

4. The ultraviolet curable resin composition for sealing an organic EL element according to claim 1 or 2, having a viscosity of 50 mPa·s or less at 25 °C.

5. A method for manufacturing an organic EL light-emitting device, which is a method for manufacturing an organic EL light-emitting device including an organic EL element and a sealing material covering the organic EL element, the method comprises: After forming the ultraviolet curable resin composition for sealing an organic EL element according to any one of claims 1 to 4 by an inkjet method, irradiating the ultraviolet curable resin composition for sealing an organic EL element with ultraviolet rays to cure it, thereby producing the sealing material.

6. An organic EL light-emitting device, which includes an organic EL element and a sealing material covering the organic EL element, The sealing material is a cured product of the ultraviolet curable resin composition for sealing an organic EL element according to any one of claims 1 to 4.

7. A touch panel, which includes the organic EL light-emitting device according to claim 6 and a touch sensor.

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