Sealing material for photoelectric conversion element, dam material, fill material, method for producing device using dam material, and method for producing device using fill material

Abstract

A sealing material for a photoelectric conversion element used in a dam-and-fill method according to the present invention comprises: (A) a cationically polymerizable compound; (B) a photocationic polymerization initiator; and (C) a sensitizer. In a contact angle measured over time using a prescribed procedure i, the contact angle θa 15 seconds after contact with liquid is 35° to 90°.

Description

Sealing material for photoelectric conversion element, dam material, fill material, method for manufacturing device using dam material, and method for manufacturing device using fill material

[0001] The present invention relates to a sealing material for photoelectric conversion elements, a dam material, a fill material, a method for manufacturing a device using the dam material, and a method for manufacturing a device using the fill material. More specifically, the present invention relates to a sealing material for photoelectric conversion elements, a dam material, a fill material, a device including a photoelectric conversion element, a method for manufacturing a device using the dam material, and a method for manufacturing a device using the fill material.

[0002] Conventionally, photoelectric conversion elements used in displays such as liquid crystal displays, organic electroluminescent displays, and electronic paper, as well as silicon-based solar cells, dye-sensitized solar cells, and organic thin-film solar cells, have been sealed with sealing materials having water vapor barrier properties. Among these, organic electroluminescent elements (OLED elements) have attracted attention as elements capable of emitting light with high brightness. OLED elements are known to be susceptible to moisture, and their light-emitting characteristics are easily deteriorated by moisture or impurities that penetrate into the OLED elements.

[0003] On the other hand, a dam-and-fill method is known as one sealing method. In the dam-and-fill method, a first curing adhesive is first applied to a substrate using a dispenser to form a ring-shaped dam (bank) for surrounding a photoelectric conversion element, and a second curing adhesive is then filled into the dam. Thereafter, the photoelectric conversion element is embedded in the second curing adhesive within the dam, and a transparent panel is placed on the dam so as to cover the dam. The second curing adhesive is then cured to bond the transparent panel to the substrate.

[0004] As an example of a sealant used in such a dam-and-fill method, Patent Document 1 (JP 2023-024361 A) discloses a thermosetting liquid composition for use as a sealant for organic light-emitting elements, which comprises a binder material containing an aliphatic tetrafunctional epoxy compound and a cationic initiator. Furthermore, Patent Document 2 (WO 2017 / 099055 A) discloses a sealant composition containing, as a dam material, at least one compound selected from N-glycidyl compounds, N-vinyl compounds, and N-allyl compounds (excluding N-glycidyl isocyanurate), in order to seal organic EL elements without directly exposing them to UV light.

[0005] Furthermore, for example, Patent Document 3 (WO 2017 / 094809) discloses a sealing composition containing, as a filler, a glycoluril compound that is weakly basic with respect to cations generated from a photocationic polymerization initiator, in order to seal an organic EL element without directly exposing it to UV light.

[0006] JP 2023-024361 A International Publication No. 2017 / 099055 International Publication No. 2017 / 094809 A

[0007] However, when a photoelectric conversion element is sealed using a conventional sealing material by the dam-and-fill method, there is room for improvement in the reliability of the sealing material to maintain the functionality of the photoelectric conversion element. More specifically, there are cases where the adhesion between the dam material and the substrate is insufficient, or the amount of the dam material dispensed using a dispenser is unstable, making it difficult to form a dam of the desired shape. Furthermore, there are cases where the wetting and spreading properties of the fill material are insufficient, resulting in insufficient adhesion between the fill material and the substrate and insufficient filling of the fill material into the dam frame.

[0008] The present inventors have conducted extensive research to improve the reliability of sealing materials and have found that a sealing product having a desired shape can be obtained by controlling the contact angle of the sealing material over time. As a result of further research, they have devised a new index for the contact angle and found that a sealing material that satisfies this index can improve reliability, thereby completing the present invention.

[0009] According to the present invention, the following sealing material and related techniques are provided.

[0010] 1. A photoelectric conversion element encapsulant used in a dam-and-fill method, comprising: (A) a cationically polymerizable compound; (B) a photocationic photopolymerization initiator; and (C) a sensitizer; wherein, in the contact angle over time measured by the following procedure i, the contact angle θa 15 seconds after application of the liquid is 35° or more and 90° or less. (Procedure i) Prepare alkali-free glass that has been degreased with acetone and then cleaned with ozone for 15 minutes. A syringe filled with the photoelectric conversion element encapsulant is set in a contact angle meter, and a droplet is made under the following condition ii. The droplet is then applied to the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Sessile drop method, θ / 2 method Field of view: Wide 2 Droplet volume: 5 μl 2.1. 2. The photoelectric conversion element encapsulant according to 1., wherein the contact angle over time measured by the procedure i is a contact angle θb of 120 seconds after contact with the liquid, of 12° or more and 32° or less. 3. The photoelectric conversion element encapsulant according to 2., wherein the contact angle θa relative to the contact angle θb (θa / θb) is 1.5 or more and 5.0 or less. 4. The photoelectric conversion element encapsulant according to any one of 1. to 3., wherein the viscosity of 0.5 ml of the photoelectric conversion element encapsulant, measured using a cone-type plate CPA-52Z at 25°C and a rotation speed of 25 rpm, is 2,000 mPa·s or more and 50,000 mPa·s or less. 5. 1. to 4. The encapsulant for photoelectric conversion elements according to any one of items 1 to 5, further comprising (D) a phosphoric acid compound. 6. The encapsulant for photoelectric conversion elements according to any one of items 1 to 5, wherein the (A) cationically polymerizable compound contains one or more compounds selected from (A-1) an alicyclic compound having an epoxy group, (A-2) an aromatic compound having an epoxy group, and (A-3) a glycidyl ether compound and derivatives thereof. 7. The encapsulant for photoelectric conversion elements according to any one of items 1 to 6, further comprising a stabilizer. 8. A dam material comprising the encapsulant for photoelectric conversion elements according to any one of items 1 to 7, and (E) an inorganic filler.9. The dam material according to 8., wherein the content of the inorganic filler (E) is 20 to 300 parts by mass relative to 100 parts by mass of the cationically polymerizable compound (A). 10. The dam material according to 8. or 9., wherein the viscosity of 0.5 ml of the dam material, measured using a cone-type plate CPA-52Z at 25°C and a rotation speed of 0.7 rpm, is 100,000 mPa·s or more and 1,200,000 mPa·s or less. 11. A cured product of the dam material according to any one of 8. to 10. 12. A device comprising a photoelectric conversion element encapsulated with the dam material according to any one of 8. to 10. 13. The device according to 12., wherein the photoelectric conversion element is an organic electroluminescence element. 14. A method for manufacturing a device, comprising the steps of: attaching a fill material and a dam material surrounding the fill material to a first member; embedding a photoelectric conversion element in the fill material; arranging a second member so as to cover the fill material and the dam material; and curing the fill material so as to bond the first member and the second member together, wherein the dam material is the dam material described in any one of 8 to 10. 15. A photoelectric conversion element encapsulant used in a dam-and-fill method, comprising: (A) a cationically polymerizable compound and (B) a photocationic polymerization initiator; and wherein, in a contact angle measurement over time as measured by the following procedure i, the contact angle θc 5 seconds after contact with the liquid is 30° or less. (Step i) Prepare alkali-free glass that has been degreased with acetone and then cleaned with ozone for 15 minutes. A syringe filled with the photoelectric conversion element encapsulant is set in a contact angle meter, a droplet is prepared under the following condition ii, and the droplet is allowed to land on the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Sessile drop method, θ / 2 method Field of view: Wide 2 Droplet amount: 5 μl 16. The photoelectric conversion element encapsulant according to 15., wherein the contact angle over time measured by the procedure i is a contact angle θd of 20° or less 30 seconds after landing.17. The encapsulant for photoelectric conversion elements according to 15., wherein the contact angle θc relative to the contact angle θd (θc / θd) is 1.0 or more and 2.3 or less. 18. The encapsulant for photoelectric conversion elements according to any one of 15. to 17., wherein the viscosity of 0.5 ml of the encapsulant for photoelectric conversion elements, measured using a cone-type plate CPA-40Z at 25°C and a rotation speed of 50 rpm, is 50 mPa·s or more and 1,000 mPa·s or less. 19. The encapsulant for photoelectric conversion elements according to any one of 15. to 18., further comprising at least one of (C2) a reactive diluent, (D) a phosphate compound, and (F) a stabilizer. 20. 15. to 19. The encapsulant for photoelectric conversion elements according to any one of the preceding paragraphs, wherein the (A) cationically polymerizable compound contains one or more compounds selected from (A-1) an alicyclic compound having an epoxy group, (A-2) an aromatic compound having an epoxy group, and (A-3) a glycidyl ether compound and derivatives thereof. 21. The encapsulant for photoelectric conversion elements according to any one of the preceding paragraphs 15. to 20., wherein the encapsulant for photoelectric conversion elements is used as a fill material. 22. A cured product of the encapsulant for photoelectric conversion elements according to any one of the preceding paragraphs 15. to 21. 23. A device comprising a photoelectric conversion element encapsulated with the encapsulant for photoelectric conversion elements according to any one of the preceding paragraphs 15. to 20. 24. The device according to the preceding paragraph 23, wherein the photoelectric conversion element is an organic electroluminescence element. 25. A method for manufacturing a device, comprising the steps of: attaching a fill material and a dam material surrounding the fill material onto a first member; embedding a photoelectric conversion element in the fill material; arranging a second member so as to cover the fill material and the dam material; and curing the fill material so as to bond the first member and the second member together, wherein the fill material is the photoelectric conversion element encapsulant described in any one of 15. to 20. 26. A polymerizable composition, wherein the contact angle θa 15 seconds after contact with the liquid is 35° or more and 90° or less, as measured by the following procedure i.(Procedure i) Prepare alkali-free glass that has been degreased with acetone and then ozone-cleaned for 15 minutes. Set a syringe filled with the polymerizable composition in a contact angle meter, create a droplet under the following condition ii, and allow the droplet to land on the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Sessile drop method, θ / 2 method Field of view: Wide 2 Droplet volume: 5 μl 27. A polymerizable composition, wherein the contact angle over time measured by the following procedure i is 30° or less 5 seconds after landing. (Procedure i) Prepare alkali-free glass that has been degreased with acetone and then ozone-cleaned for 15 minutes. Set a syringe filled with the polymerizable composition in a contact angle meter, create a droplet under the following condition ii, and allow the droplet to land on the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: change over time Control method: standard Analysis technique and method: droplet method, θ / 2 method Field of view: wide 2 Droplet amount: 5 μl.

[0011] According to the present invention, a technique can be provided that can improve the reliability of a device that uses a sealing material.

[0012] It is a schematic cross-sectional view showing an example of the device of this embodiment. It is a diagram showing the positional relationship between the fill material and the dam material in a plan view of the device of this embodiment. It is a schematic view showing an example of a manufacturing method of the device of this embodiment.

[0013] In this specification, the notation "a to b" in the description of a numerical range means a or more and b or less, unless otherwise specified. For example, "1 to 5 mass %" means "1 mass % or more and 5 mass % or less." Furthermore, the lower limit and upper limit of a numerical range can be arbitrarily combined with the lower limit and upper limit of another numerical range, respectively. Unless otherwise specified, each of the components and materials exemplified in this specification may be used alone or in combination of two or more types.

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings. When multiple identical components are present in the same drawing, only one of the components may be labeled with a reference symbol, and not all of the components may be labeled with a reference symbol. All drawings are for illustrative purposes only. The shapes and dimensional ratios of each component in the drawings do not necessarily correspond to the actual product.

[0015] The dam and fill method is a process used in sealing technology for electronic components, etc., in which a dam material and a fill material are combined. The dam material has a higher viscosity and better shape retention than the fill material and is used to form a wall (dam). The fill material has a higher fluidity than the dam material and is used to fill the area surrounded by the dam material. The sealing structure can be completed by partially or fully curing the dam material and fill material.

[0016] <Sealant for photoelectric conversion element> Hereinafter, an example of a preferred embodiment of the sealant for photoelectric conversion element will be described. This embodiment is a composition. The composition is preferably a polymerizable composition. The polymerizable composition preferably contains a polymerizable compound and a polymerization initiator. The polymerizable compound is preferably (A) a cationically polymerizable compound. The polymerization initiator is preferably a photopolymerization initiator or a cationic polymerization initiator, and more preferably (B) a photocationic polymerization initiator. The composition is preferably a sealant for photoelectric conversion element.

[0017] 1. First Embodiment The sealing material for photoelectric conversion elements of this embodiment is used in a dam-and-fill method, and contains (A) a cationically polymerizable compound, (B) a photocationic polymerization initiator, and (C) a sensitizer. In the contact angle over time measured by the following procedure i, the contact angle θa 15 seconds after contact with the liquid is 35° or more and 90° or less.

[0018] (Procedure i) Prepare alkali-free glass that has been degreased with acetone and then cleaned with ozone for 15 minutes. A syringe filled with the photoelectric conversion element encapsulant is set in a contact angle meter, and a droplet is prepared under the following condition ii. The droplet is then placed on the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Sessile drop method, θ / 2 method Field of view: Wide 2 Droplet volume: 5 μl

[0019] By setting the contact angle θa 15 seconds after application within the above numerical range, the shape accuracy and positional accuracy of the photoelectric conversion element encapsulant can be improved, and an encapsulated body of a desired shape can be obtained. As a result, the reliability of devices using the photoelectric conversion element encapsulant of this embodiment can be improved. While the details of this are unclear, it is presumed as follows. First, when the photoelectric conversion element encapsulant is applied with a dispenser, it is discharged from the tip of a nozzle and is arranged to form the desired shape while adhering to the substrate (first member). At this time, the photoelectric conversion element encapsulant that comes into contact with the substrate does not completely wet and spread, but gradually stabilizes its shape and becomes solid. Therefore, it is believed that by controlling the contact angle when the photoelectric conversion element encapsulant comes into contact with the substrate and stabilizes its shape, it is possible to control the arrangement and shape of the photoelectric conversion element encapsulant with higher precision. Furthermore, when a dam is formed using the photoelectric conversion element encapsulant, the dam can be created as designed, and uniformity is achieved by blocking the outflow of the internal fill material as a dam material, which is presumed to improve the reliability of devices using photoelectric conversion elements.

[0020] [Contact Angle] The contact angle θa 15 seconds after contact with the liquid is 35° or more, preferably 38° or more, and more preferably 40° or more. This reduces uneven discharge during discharge, suppresses the generation of waves and bubbles, and improves reliability. On the other hand, the contact angle θa 15 seconds after contact with the liquid is 90° or less, preferably 85° or less, and more preferably 70° or less. This reduces uneven discharge during discharge, suppresses the generation of waves and bubbles, and improves reliability. Furthermore, from the viewpoint of obtaining even higher reliability, it is even more preferably 55° or less.

[0021] Furthermore, in the contact angle over time measured by procedure i, the contact angle θb 120 seconds after contact with the liquid is preferably 12° or more and 32° or less. 120 seconds after contact with the liquid, it is considered that the discharged photoelectric conversion element sealing material has wetted and spread to a certain extent, and its shape is almost stable. Therefore, by controlling the contact angle θb 120 seconds after contact with the liquid, a dam with a more stable width can be obtained.

[0022] The ratio of the contact angle θa (°) (θa / θb) to the contact angle θb (°) is preferably 1.3 or more, more preferably 1.4 or more, while the ratio of the contact angle θa (°) (θa / θb) to the contact angle θb (°) is preferably 3.0 or less, more preferably 2.6 or less, and even more preferably 2.2 or less.

[0023] A photoelectric conversion element encapsulant that satisfies the above-mentioned contact angle can be realized by selecting the types of components constituting the photoelectric conversion element encapsulant and adjusting the amounts of the components. Specific examples include using (A-1) an alicyclic compound having an epoxy group, or using (D) a phosphoric acid compound and a stabilizer, in order to obtain wettability. Furthermore, in order to ensure the desired physical properties of the photoelectric conversion element encapsulant, a method of combining (A-2) an aromatic compound having an epoxy group, (A-3) a glycidyl ether compound, or the like with (A-1) an alicyclic compound having an epoxy group can also be mentioned.

[0024] [Viscosity] Furthermore, the viscosity of 0.5 ml of the photoelectric conversion element encapsulant, measured using a cone-type plate CPA-52Z at 25°C and a rotation speed of 25 rpm, is preferably 2,000 mPa·s or more, more preferably 3,000 mPa·s or more, and even more preferably 3,500 mPa·s or more. On the other hand, the viscosity of the photoelectric conversion element encapsulant is preferably 50,000 mPa·s or less, more preferably 40,000 mPa·s or less, and even more preferably 30,000 mPa·s or less. By setting the viscosity of the photoelectric conversion element encapsulant within the above numerical range, discharge unevenness during discharge can be reduced and the generation of waviness and bubbles can be suppressed. The term "wavy" refers to a phenomenon that occurs when the photoelectric conversion element encapsulant cannot be applied in a uniform line, when the photoelectric conversion element encapsulant does not spread evenly and the fluidity is reduced, or when the photoelectric conversion element encapsulant has too high a viscosity and cannot be uniformly discharged. The term "air bubbles" refers to a phenomenon that occurs when air bubbles contained in the photoelectric conversion element encapsulant do not escape even after application, or when bubbles are generated due to poor wetting of the substrate surface after application.

[0025] The components constituting the sealing material for photoelectric conversion elements will be described below.

[0026] (A) Cationically Polymerizable Compound The sealing material for a photoelectric conversion element of this embodiment contains (A) a cationically polymerizable compound as an essential component. (A) The cationically polymerizable compound is preferably photopolymerizable.

[0027] The cationically polymerizable compound (A) contains one or more selected from (A-1) an alicyclic compound having an epoxy group, (A-2) an aromatic compound having an epoxy group, and (A-3) a glycidyl ether compound and derivatives thereof. This allows for good coating properties, adhesion, and low moisture permeability. The cationically polymerizable compound (A) may also contain one or more halogen elements, such as one or more selected from the group consisting of fluorine and bromine.

[0028] (A-1) Alicyclic Compound Having Epoxy Group Examples of alicyclic compounds having an epoxy group (hereinafter sometimes referred to as alicyclic epoxy compounds) include compounds or derivatives thereof obtained by epoxidizing a compound having at least one cycloalkane ring (e.g., a cyclohexene ring, a cyclopentene ring, a pinene ring, etc.) with an appropriate oxidizing agent such as hydrogen peroxide or a peracid, and hydrogenated epoxy compounds obtained by hydrogenating an aromatic epoxy compound (e.g., bisphenol A epoxy resin, bisphenol F epoxy resin, etc.). One or more of these compounds may be selected and used.

[0029] Examples of alicyclic epoxy compounds include 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, 3,4-epoxycyclohexylalkyl(meth)acrylate (for example, 3,4-epoxycyclohexylmethyl(meth)acrylate), (3,3',4,4'-diepoxy)bicyclohexyl, hydrogenated bisphenol A epoxy resin, and hydrogenated bisphenol F epoxy resin.

[0030] Among the alicyclic epoxy compounds, those having a 1,2-epoxycyclohexane structure are preferred. Among the alicyclic epoxy compounds having a 1,2-epoxycyclohexane structure, the compound represented by the following formula (A1-1) is preferred.

[0031] (In formula (A1-1), X represents a single bond or a linking group (a divalent group having one or more atoms), and the linking group is a divalent hydrocarbon group, a carbonyl group, an ether bond, an ester bond, a carbonate group, an amide bond, or a group in which a plurality of these are linked together.)

[0032] X is preferably a linking group. Among linking groups, a functional group having an ester bond is preferred. Among these, 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate is preferred.

[0033] The molecular weight of the alicyclic epoxy compound is preferably 450 or less, more preferably 400 or less, even more preferably less than 300, and even more preferably 100 to 280, from the viewpoint of moisture permeability and storage stability.

[0034] When the alicyclic epoxy compound has a molecular weight distribution, the number average molecular weight of the alicyclic epoxy compound is preferably within the above range. In this specification, the number average molecular weight is a value measured by gel permeation chromatography (GPC) in terms of polystyrene.

[0035] (A-2) Aromatic Compound Having Epoxy Group As the aromatic compound having an epoxy group (hereinafter, also referred to as aromatic epoxy compound), any of a monomer, oligomer, and polymer can be used, and examples thereof include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, fluorene type epoxy resin, novolac phenol type epoxy resin, cresol novolac type epoxy resin, and modified products thereof.

[0036] The epoxy resin may also be a multifunctional epoxy resin having two or more epoxy groups. Examples of epoxy resins having two or more epoxy groups (particularly two) include bisphenol A-type multifunctional epoxy resins, bisphenol F-type multifunctional epoxy resins, bisphenol AF-type multifunctional epoxy resins, hydrogenated bisphenol A-type multifunctional epoxy resins, and biphenyl-type multifunctional epoxy resins. Examples of epoxy resins having three or more epoxy groups include naphthalene-type multifunctional epoxy resins, phenol novolac-type multifunctional epoxy resins, cresol novolac-type multifunctional epoxy resins, dicyclopentadiene-type multifunctional epoxy resins, glycidyl amine-type multifunctional epoxy resins, glycidyl ester-type multifunctional epoxy resins, rubber-modified multifunctional epoxy resins, chelate-modified multifunctional epoxy resins, multifunctional alicyclic epoxy resins, and multifunctional epoxidized polybutadienes.

[0037] One or more of these epoxy resins may be selected and used. Among them, aromatic epoxy compounds having a bisphenol structure are preferred. Among the aromatic epoxy compounds having a bisphenol structure, compounds represented by the following formula (A2-1) are preferred.

[0038] (In formula (A2-1), n ​​represents a real number from 0 to 30, and R ２１ , R ２２ , R ２３ and R ２４ each independently represents a hydrogen atom or a substituted or unsubstituted alkyl group having 1 to 5 carbon atoms.

[0039] R ２１ , R ２２ , R ２３ and R ２４ is preferably a hydrogen atom or a methyl group. ２１ , R ２２ , R ２３ and R ２４ and n are preferably the same. n is preferably a real number of 0.1 to 30.

[0040] Among the aromatic epoxy compounds having a bisphenol structure, one or more selected from the group consisting of bisphenol A type epoxy resins and bisphenol F type epoxy resins are preferred.

[0041] (A-2-1) Bisphenol A-type epoxy resin Bisphenol A-type epoxy resin is, for example, a bisphenol A-type epoxy resin represented by the formula (A2-1) ２１ , R ２２ , R ２３ and R ２４ may be an epoxy resin in which R is a methyl group. Bisphenol A epoxy resins refer to, for example, those obtained by condensing bisphenol A and epichlorohydrin in the presence of an alkali catalyst. Furthermore, modified epoxy resins in which the epoxy groups or hydroxyl groups of the above-mentioned bisphenol A epoxy resins are reacted with vegetable oil fatty acids or modifiers may also be used. Note that hydrogenated epoxy compounds obtained by hydrogenating bisphenol A epoxy resins (for example, hydrogenated bisphenol A epoxy resins corresponding to the above-mentioned alicyclic epoxy compounds) are not included in the bisphenol A epoxy resins.

[0042] (A-2-2) Bisphenol F Epoxy Resin Bisphenol F epoxy resin is, for example, a bisphenol F epoxy resin represented by the formula (A2-1) R ２１ , R ２２ , R ２３ and R ２４ is a hydrogen atom. Bisphenol F epoxy resins refer to, for example, those obtained by condensing bisphenol F and epichlorohydrin in the presence of an alkali catalyst. Furthermore, modified epoxy resins obtained by reacting the epoxy groups or hydroxyl groups of the above-mentioned bisphenol F epoxy resins with vegetable oil fatty acids or modifiers may also be used. Note that hydrogenated epoxy compounds obtained by hydrogenating bisphenol F epoxy resins (for example, hydrogenated bisphenol F epoxy resins corresponding to the above-mentioned alicyclic epoxy compounds) are not included in the bisphenol F epoxy resins.

[0043] The molecular weight of the aromatic epoxy compound, particularly the molecular weight of the bisphenol A epoxy resin (A-2-1) and the bisphenol F epoxy resin (A-2-2), is preferably 100 to 5,000, more preferably 150 to 1,000, and most preferably 200 to 450, from the viewpoint of moisture permeability and the like.

[0044] When the aromatic epoxy compound has a molecular weight distribution, the number average molecular weight of the aromatic epoxy compound is preferably within the above range. In this specification, the number average molecular weight refers to a value measured by gel permeation chromatography (GPC) under the above-mentioned measurement conditions, expressed in terms of polystyrene.

[0045] (A-3) Glycidyl Ether Compounds Examples of the glycidyl ether compounds include monoglycidyl ether compounds and polyglycidyl ether compounds.

[0046] The monoglycidyl ether compound is not particularly limited, and examples thereof include methyl glycidyl ether, 2-ethylhexyl glycidyl ether, butyl glycidyl ether, decyl glycidyl ether, mixed alkyl glycidyl ethers having 12 to 13 carbon atoms, phenyl-2-methyl glycidyl ether, cetyl glycidyl ether, stearyl glycidyl ether, p-sec-butylphenyl glycidyl ether, p-tert-butylphenyl glycidyl ether, glycidyl methacrylate, isopropyl glycidyl ether, allyl glycidyl ether, ethyl glycidyl glycidyl ether, 2-methyloctyl glycidyl ether, phenyl glycidyl ether, 4-n-butylphenyl glycidyl ether, 4-phenylphenol glycidyl ether, cresyl glycidyl ether, dibromocresyl glycidyl ether, decyl glycidyl ether, methoxypolyethylene glycol monoglycidyl ether, ethoxypolyethylene glycol monoglycidyl ether, butoxypolyethylene glycol monoglycidyl ether, phenoxypolyethylene glycol monoglycidyl ether, and dibromophenyl glycidyl ether.

[0047] The polyglycidyl ether compound is not particularly limited, but examples thereof include diglycidyl ethers of alkylene glycols (for example, diglycidyl ethers of ethylene glycol, diglycidyl ethers of propylene glycol, diglycidyl ethers of 1,6-hexanediol, etc.), polyglycidyl ethers of polyhydric alcohols (for example, di- or triglycidyl ethers of glycerin or its alkylene oxide adducts, etc.), and diglycidyl ethers of polyalkylene glycols (for example, diglycidyl ethers of polyethylene glycol or its alkylene oxide adducts, diglycidyl ethers of polypropylene glycol or its alkylene oxide adducts, etc.). Here, examples of alkylene oxides include aliphatic ones such as ethylene oxide and propylene oxide.

[0048] Among these, the glycidyl ether compound preferably contains one or more halogen elements, more preferably bromine element, and specific examples thereof include halophenyl glycidyl ethers such as bromophenyl glycidyl ether and dibromophenyl glycidyl ether, brominated cresyl glycidyl ether, and brominated bisphenol A epoxy resins (e.g., diglycidyl ether of tetrabromobisphenol A).

[0049] The cationically polymerizable compound (A) of the present embodiment may contain a cationically polymerizable compound other than the above-mentioned (A-1), (A-2), and (A-3), and may contain, for example, one or more of an oxetane compound and a vinyl ether compound.

[0050] The oxetane compound is not particularly limited, but examples thereof include 3-ethyl-3-hydroxymethyloxetane (product name: Aron Oxetane OXT-101, manufactured by Toagosei Co., Ltd.), 1,4-bis[(3-ethyl-3-oxetanyl)methoxymethyl]benzene (product name: OXT-121, manufactured by Toagosei Co., Ltd.), 3-ethyl-3-(phenoxymethyl)oxetane (product name: OXT-211, manufactured by Toagosei Co., Ltd.), di(1-ethyl-(3-oxetanyl))methyl ether (product name: OXT-221, manufactured by Toagosei Co., Ltd.), and 3-ethyl-3-(2-ethylhexyloxymethyl)oxetane (product name: OXT-212, manufactured by Toagosei Co., Ltd.). An oxetane compound refers to a compound having one or more oxetane rings in the molecule.

[0051] The vinyl ether compound is not particularly limited, but examples thereof include di- or trivinyl ether compounds such as ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol monovinyl ether, triethylene glycol divinyl ether, propylene glycol divinyl ether, dipropylene glycol divinyl ether, butanediol divinyl ether, hexanediol divinyl ether, cyclohexanedimethanol divinyl ether, and trimethylolpropane trivinyl ether; and monovinyl ether compounds such as ethylene glycol monovinyl ether, hydroxyethyl monovinyl ether, hydroxynonyl monovinyl ether, ethyl vinyl ether, n-butyl vinyl ether, isobutyl vinyl ether, octadecyl vinyl ether, cyclohexyl vinyl ether, hydroxybutyl vinyl ether, 2-ethylhexyl vinyl ether, cyclohexanedimethanol monovinyl ether, n-propyl vinyl ether, isopropyl vinyl ether, isopropenyl ether o-propylene carbonate, dodecyl vinyl ether, diethylene glycol monovinyl ether, and octadecyl vinyl ether.

[0052] The content of the alicyclic compound having an epoxy group (A-1) is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and even more preferably 15 parts by mass or more, per 100 parts by mass of the cationically polymerizable compound (A). This tends to further improve the durability of the cured product. On the other hand, the content of the alicyclic compound having an epoxy group (A-1) is preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 25 parts by mass or less, per 100 parts by mass of the cationically polymerizable compound (A).

[0053] When the (A-2) aromatic compound having an epoxy group is contained, the content of the (A-2) aromatic compound having an epoxy group is preferably 40 parts by mass or more, more preferably 45 parts by mass or more, and even more preferably 50 parts by mass or more, per 100 parts by mass of the (A) cationically polymerizable compound. This tends to further improve the durability of the cured product. On the other hand, the upper limit of the content of the (A-2) aromatic compound having an epoxy group is not particularly limited, and may be, for example, 70 parts by mass or less, per 100 parts by mass of the (A) cationically polymerizable compound, or the (A-2) aromatic compound having an epoxy group may not be contained.

[0054] When the (A-3) glycidyl ether compound is contained, the content of the (A-3) glycidyl ether compound is preferably 60 parts by mass or more, more preferably 65 parts by mass or more, and even more preferably 70 parts by mass or more, per 100 parts by mass of the (A) cationically polymerizable compound. This tends to further improve the durability of the cured product. On the other hand, there is no particular upper limit on the content of the (A-3) glycidyl ether compound, and it may be, for example, 85 parts by mass or less per 100 parts by mass of the (A) cationically polymerizable compound, or the (A-3) glycidyl ether compound may not be contained.

[0055] In 100 parts by mass of the cationically polymerizable compound (A), the total content of the alicyclic compound (A-1) having an epoxy group, the aromatic compound (A-2) having an epoxy group, and the glycidyl ether compound (A-3) is preferably 60 parts by mass or more, more preferably 80 parts by mass or more, most preferably 90 parts by mass or more, and even more preferably 100 parts by mass.

[0056] (B) Photocationic Polymerization Initiator The photoelectric conversion element sealing material of this embodiment contains (B) a photocationic polymerization initiator as an essential component. When a photocationic polymerization initiator is used, the photoelectric conversion element sealing material of this embodiment can be cured by irradiation with energy rays such as ultraviolet rays.

[0057] The photocationic polymerization initiator (B) is not particularly limited, but may be an arylsulfonium salt derivative (for example, Cyracure UVI-6990 and Cyracure UVI-6974 manufactured by The Dow Chemical Company, Adekaoptomer SP-150, Adekaoptomer SP-152, Adekaoptomer SP-170, and Adekaoptomer SP-172 manufactured by Asahi Denka Kogyo Co., Ltd., CPI-100P, CPI-101A, and CP I-200K, CPI-210S, CPI-310FG, LW-S1, Cibacur 1190 manufactured by Double Bond Corporation, etc.), aryliodonium salt derivatives (for example, Irgacure 250 manufactured by Ciba Specialty Chemicals, RP-2074 manufactured by Rhodia Japan), allene-ion complex derivatives, diazonium salt derivatives, triazine initiators, and acid generators such as other halides. The cationic species of the photocationic polymerization initiator is preferably an onium salt represented by formula (B-1).

[0058] The photocationic polymerization initiator (B) is not particularly limited, but examples thereof include onium salts represented by formula (B-1).

[0059] (A represents an element of Group VIA to Group VIIA with a valence of m. m represents 1 to 2. p represents 0 to 3. m and p are preferably integers. R represents an organic group bonded to A. D represents a group of the following formula (B-1-1): In formula (B-1-1), E represents a divalent group, and G represents —O—, —S—, —SO—, or —SO ２ -, -NH-, -NR'-, -CO-, -COO-, -CONH-, an alkylene or phenylene group having 1 to 3 carbon atoms (R' is an alkyl group having 1 to 5 carbon atoms or an aryl group having 6 to 10 carbon atoms). a represents 0 to 5. a+1 E's and a G's may be the same or different. a is preferably an integer. X －is the counter ion of the onium, and the number of counter ions per molecule is p+1.)

[0060] The onium ion of formula (B-1) is not particularly limited, and examples thereof include 4-(phenylthio)phenyldiphenylsulfonium, bis[4-(diphenylsulfonio)phenyl]sulfide, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2-chlorophenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolyls ... Examples of such sulfonium compounds include dihydroanthracen-2-yldiphenylsulfonium, 2-[(di-p-tolyl)sulfonio]thioxanthone, 2-[(diphenyl)sulfonio]thioxanthone, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium, 5-(4-methoxyphenyl)thiaanthrenenium, 5-phenylthiaanthrenenium, diphenylphenacylsulfonium, 4-hydroxyphenylmethylbenzylsulfonium, 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium, 4-hydroxyphenylmethylphenacylsulfonium, and octadecylmethylphenacylsulfonium.

[0061] R is an organic group bonded to A. R represents, for example, an aryl group having 6 to 30 carbon atoms, a heterocyclic group having 4 to 30 carbon atoms, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or an alkynyl group having 2 to 30 carbon atoms, which may be substituted with at least one selected from the group consisting of alkyl, hydroxy, alkoxy, alkylcarbonyl, arylcarbonyl, alkoxycarbonyl, aryloxycarbonyl, arylthiocarbonyl, acyloxy, arylthio, alkylthio, aryl, heterocyclic, aryloxy, alkylsulfinyl, arylsulfinyl, alkylsulfonyl, arylsulfonyl, alkyleneoxy, amino, cyano, nitro groups, and halogen. The number of R is m+p(m-1)+1, and they may be the same or different. Two or more R may be directly connected to each other or may be connected to each other by -O-, -S-, -SO-, -SO ２ They may be bonded via -, -NH-, -NR'-, -CO-, -COO-, -CONH-, an alkylene group having 1 to 3 carbon atoms, or a phenylene group to form a ring structure containing the element A, where R' is an alkyl group having 1 to 5 carbon atoms or an aryl group having 6 to 10 carbon atoms.

[0062] Examples of the aryl group having 6 to 30 carbon atoms include monocyclic aryl groups such as phenyl group, and condensed polycyclic aryl groups such as naphthyl, anthracenyl, phenanthrenyl, pyrenyl, chrysenyl, naphthacenyl, benzanthracenyl, anthraquinolyl, fluorenyl, naphthoquinone, and anthraquinone.

[0063] The above-mentioned aryl group having 6 to 30 carbon atoms, heterocyclic group having 4 to 30 carbon atoms, alkyl group having 1 to 30 carbon atoms, alkenyl group having 2 to 30 carbon atoms, or alkynyl group having 2 to 30 carbon atoms may have at least one substituent. Examples of the substituent include linear alkyl groups having 1 to 18 carbon atoms such as methyl, ethyl, propyl, butyl, pentyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, and octadecyl; alkyl groups having 1 to 18 carbon atoms such as isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, neopentyl, tert-pentyl, and isohexyl; cycloalkyl groups having 3 to 18 carbon atoms, such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl; hydroxy groups; linear or branched alkoxy groups having 1 to 18 carbon atoms, such as methoxy, ethoxy, propoxy, isopropoxy, butoxy, isobutoxy, sec-butoxy, tert-butoxy, hexyloxy, decyloxy, and dodecyloxy; acetyl, propionyl, butanoyl, 2-methylpropionyl, heptanoyl, 2-methylbutanoyl, 3-methylbutanoyl, octanoyl, decanoyl, dodecanoyl, and octanoyl. linear or branched alkylcarbonyl groups having 2 to 18 carbon atoms, such as octadecanoyl; arylcarbonyl groups having 7 to 11 carbon atoms, such as benzoyl and naphthoyl; linear or branched alkoxycarbonyl groups having 2 to 19 carbon atoms, such as methoxycarbonyl, ethoxycarbonyl, propoxycarbonyl, isopropoxycarbonyl, butoxycarbonyl, isobutoxycarbonyl, sec-butoxycarbonyl, tert-butoxycarbonyl, octyloxycarbonyl, tetradecyloxycarbonyl, and octadecyloxycarbonyl; phenoxycarbonyl, naphthoxy aryloxycarbonyl groups having 7 to 11 carbon atoms, such as carbonyl; arylthiocarbonyl groups having 7 to 11 carbon atoms, such as phenylthiocarbonyl and naphthoxythiocarbonyl; linear or branched acyloxy groups having 2 to 19 carbon atoms, such as acetoxy, ethylcarbonyloxy, propylcarbonyloxy, isopropylcarbonyloxy, butylcarbonyloxy, isobutylcarbonyloxy, sec-butylcarbonyloxy, tert-butylcarbonyloxy, octylcarbonyloxy, tetradecylcarbonyloxy, and octadecylcarbonyloxy;Phenylthio, 2-methylphenylthio, 3-methylphenylthio, 4-methylphenylthio, 2-chlorophenylthio, 3-chlorophenylthio, 4-chlorophenylthio, 2-bromophenylthio, 3-bromophenylthio, 4-bromophenylthio, 2-fluorophenylthio, 3-fluorophenylthio, 4-fluorophenylthio, 2-hydroxyphenylthio, 4-hydroxyphenylthio, 2-methoxyphenylthio, 4-methoxyphenylthio, 1-naphthylthio, 2-naphthylthio, 4-[4-(phenylthio)benzoyl ]phenylthio, 4-[4-(phenylthio)phenoxy]phenylthio, 4-[4-(phenylthio)phenyl]phenylthio, 4-(phenylthio)phenylthio, 4-benzoylphenylthio, 4-benzoyl-2-chlorophenylthio, 4-benzoyl-3-chlorophenylthio, 4-benzoyl-3-methylthiophenylthio, 4-benzoyl-2-methylthiophenylthio, 4-(4-methylthiobenzoyl)phenylthio, 4-(2-methylthiobenzoyl)phenylthio, 4-(p-methylbenzoyl)phenylthio, 4-(p arylthio groups having 6 to 20 carbon atoms such as 4-(p-tert-butylbenzoyl)phenylthio, 4-(p-ethylbenzoyl)phenylthio, 4-(p-isopropylbenzoyl)phenylthio, and 4-(p-tert-butylbenzoyl)phenylthio; straight-chain or branched alkylthio groups having 1 to 18 carbon atoms such as methylthio, ethylthio, propylthio, isopropylthio, butylthio, isobutylthio, sec-butylthio, tert-butylthio, pentylthio, isopentylthio, neopentylthio, tert-pentylthio, octylthio, decylthio, and dodecylthio; phenyl, tolyl, dimethylphenyl, aryl groups having 6 to 10 carbon atoms, such as naphthyl; heterocyclic groups having 4 to 20 carbon atoms, such as thienyl, furanyl, pyranyl, pyrrolyl, oxazolyl, thiazolyl, pyridyl, pyrimidyl, pyrazinyl, indolyl, benzofuranyl, benzothienyl, quinolyl, isoquinolyl, quinoxalinyl, quinazolinyl, carbazolyl, acridinyl, phenothiazinyl, phenazinyl, xanthenyl, thianthrenyl, phenoxazinyl, phenoxathiinyl, chromanyl, isochromanyl, dibenzothienyl, xanthonyl, thioxanthonyl, and dibenzofuranyl;Aryloxy groups having 6 to 10 carbon atoms, such as phenoxy and naphthyloxy; linear or branched alkylsulfinyl groups having 1 to 18 carbon atoms, such as methylsulfinyl, ethylsulfinyl, propylsulfinyl, isopropylsulfinyl, butylsulfinyl, isobutylsulfinyl, sec-butylsulfinyl, tert-butylsulfinyl, pentylsulfinyl, isopentylsulfinyl, neopentylsulfinyl, tert-pentylsulfinyl and octylsulfinyl; and alkylsulfinyl groups having 1 to 18 carbon atoms, such as phenylsulfinyl, tolylsulfinyl and naphthylsulfinyl. arylsulfinyl groups having 6 to 10 carbon atoms; linear or branched alkylsulfonyl groups having 1 to 18 carbon atoms, such as methylsulfonyl, ethylsulfonyl, propylsulfonyl, isopropylsulfonyl, butylsulfonyl, isobutylsulfonyl, sec-butylsulfonyl, tert-butylsulfonyl, pentylsulfonyl, isopentylsulfonyl, neopentylsulfonyl, tert-pentylsulfonyl, and octylsulfonyl; arylsulfonyl groups having 6 to 10 carbon atoms, such as phenylsulfonyl, tolylsulfonyl (tosyl), and naphthylsulfonyl; formula (B-1-2);

[0064] (Q represents a hydrogen atom or a methyl group, and k represents an integer of 1 to 5); an unsubstituted amino group; an amino group mono- or di-substituted with alkyl having 1 to 5 carbon atoms and / or aryl having 6 to 10 carbon atoms; a cyano group; a nitro group; and halogen atoms such as fluorine, chlorine, bromine, and iodine.

[0065] In formula (B-1), p is [D-A ＋ R ｍ－１ ] represents the number of repeating units of the bond, and is preferably an integer of 0 to 3.

[0066] The onium ion [A ＋ Preferred examples of the cation include sulfonium, iodonium, and selenium, and typical examples include the following:

[0067] Examples of sulfonium ions include triphenylsulfonium, tri-p-tolylsulfonium, tri-o-tolylsulfonium, tris(4-methoxyphenyl)sulfonium, 1-naphthyldiphenylsulfonium, 2-naphthyldiphenylsulfonium, tris(4-fluorophenyl)sulfonium, tri-1-naphthylsulfonium, tri-2-naphthylsulfonium, tris(4-hydroxyphenyl)sulfonium, 4-(phenylthio)phenyldiphenylsulfonium, 4-(p-tolylthio)phenyldi-p-tolylsulfonium, 4-(4-methoxyphenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(phenylthio)phenylbis(4-methoxyphenyl)sulfonium, 4-(phenylthio)phenyldi-p-tolylsulfonium, bis[4-(diphenylsulfonio)phenyl nyl]sulfide, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methylphenyl)sulfonio]phenyl}sulfide, bis{4-[bis(4-methoxyphenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2-chlorophenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoyl-2-chlorophenylthio)phenyldiphenylsulfonium, 4-(4-benzoylphenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-Dihydroanthracen-2-yldiphenylsulfonium, 2-[(di-p-tolyl)sulfonio]thioxanthone, 2-[(diphenyl)sulfonio]thioxanthone, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldiphenylsulfonium, 4-[4-(benzoylphenylthio)]phenyldi-p-tolylsulfonium, 4-[4-(benzoylphenylthio)]phenyldi-p-tolylsulfonium triarylsulfoniums such as 5-(4-methoxyphenyl)thiaanthrenenium, 5-phenylthiaanthrenenium, 5-tolylthiaanthrenenium, 5-(4-ethoxyphenyl)thiaanthrenenium, and 5-(2,4,6-trimethylphenyl)thiaanthrenenium; diarylsulfoniums such as diphenylphenacylsulfonium, diphenyl 4-nitrophenacylsulfonium, diphenylbenzylsulfonium, and diphenylmethylsulfonium; monoarylsulfoniums such as phenylmethylbenzylsulfonium, 4-hydroxyphenylmethylbenzylsulfonium, 4-methoxyphenylmethylbenzylsulfonium, 4-acetocarbonyloxyphenylmethylbenzylsulfonium, 2-naphthylmethylbenzylsulfonium, 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium, phenylmethylphenacylsulfonium, 4-hydroxyphenylmethylphenacylsulfonium, 4-methoxyphenylmethylphenacylsulfonium, 4-acetocarbonyloxyphenylmethylphenacylsulfonium, 2-naphthylmethylphenacylsulfonium, 2-naphthyloctadecylphenacylsulfonium, and 9-anthracenylmethylphenacylsulfonium; and trialkylsulfoniums such as dimethylphenacylsulfonium, phenacyltetrahydrothiophenium, dimethylbenzylsulfonium, benzyltetrahydrothiophenium, and octadecylmethylphenacylsulfonium.

[0068] Among these onium ions, one or more of sulfonium ions and iodonium ions are preferred, with sulfonium ions being more preferred. Examples of sulfonium ions include triphenylsulfonium, tri-p-tolylsulfonium, 4-(phenylthio)phenyldiphenylsulfonium, bis[4-(diphenylsulfonio)phenyl]sulfide, bis[4-{bis[4-(2-hydroxyethoxy)phenyl]sulfonio}phenyl]sulfide, bis{4-[bis(4-fluorophenyl)sulfonio]phenyl}sulfide, 4-(4-benzoyl-2-chlorophenylthio)phenylbis(4-fluorophenyl)sulfonium, 4-(4-benzoylphenylthio)phenyldiphenylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium, 7-isopropyl-9-oxo-10-thia-9,10-dihydroanthracen-2-yldi-p-tolylsulfonium, and 7-isopropyl-9-oxo-10-thia-9 , 10-dihydroanthracen-2-yldiphenylsulfonium, 2-[(di-p-tolyl)sulfonio]thioxanthone, 2-[(diphenyl)sulfonio]thioxanthone, 4-[4-(4-tert-butylbenzoyl)phenylthio]phenyldi-p-tolylsulfonium, 4-[4-(benzoylphenylthio)]phenyldiphenylsulfonium, 5-(4-methoxyphenyl)thiaanthrenenium, 5-phenylthiaanthrenenium, diphenylphenacylsulfonium, 4-hydroxyphenylmethylbenzylsulfonium, 2-naphthylmethyl(1-ethoxycarbonyl)ethylsulfonium, 4-hydroxyphenylmethylphenacylsulfonium and octadecylmethylphenacylsulfonium are preferred.

[0069] In formula (B-1), X － is a counter ion. The number of counter ions is p+1 per molecule. The counter ion is not particularly limited, but examples thereof include boron compounds, phosphorus compounds, antimony compounds, arsenic compounds, halides such as alkylsulfonic acid compounds, and methide compounds. X － For example, F － , Cl － ,Br － , I － Halogen ions such as OH－ ClO ４ － ; FSO ３ － , ClSO ３ － , C.H. ３ SO ３ － , C ６ H ５ SO ３ － , C.F. ３ SO ３ － sulfonate ions such as HSO ４ － , S.O. ４ ２－ sulfate ions such as HCO ３ － , CO ３ ２－ Carbonate ions such as H ２ P.O. ４ － , H.P.O. ４ ２－ , P.O. ４ ３－ phosphate ions such as PF ６ － , P.F. ５ OH － fluorophosphate ions such as fluorinated alkyl fluorophosphate ions; BF ４ － , B(C ６ F ５ ) ４ － , B(C ６ H ４ CF ３ ) ４ － borate ions such as AlCl ４ － ;BiF ６ － Other examples include SbF ６ － , SbF ５ OH － Fluoroantimonate ions such as AsF ６ － , AsF ５ OH － and the like fluoroarsenate ions.

[0070] Examples of the fluorinated alkylfluorophosphate ion include a fluorinated alkylfluorophosphate ion represented by formula (B-1-3) and the like.

[0071] [(Rf) ｂ PF ６－ｂ ]- (B-1-3)

[0072] In formula (B-1-3), Rf represents an alkyl group substituted with a fluorine atom. The number b of Rf is 1 to 5, and is preferably an integer. The b Rfs may be the same or different. The number b of Rfs is more preferably 2 to 4, and most preferably 2 to 3. In the fluorinated alkylfluorophosphate ion represented by formula (B-1-3), Rf represents an alkyl group substituted with a fluorine atom, and preferably has 1 to 8 carbon atoms, and more preferably has 1 to 4 carbon atoms. Examples of the alkyl group include linear alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, and octyl; branched alkyl groups such as isopropyl, isobutyl, sec-butyl, and tert-butyl; and cycloalkyl groups such as cyclopropyl, cyclobutyl, cyclopentyl, and cyclohexyl. Specific examples include CF ３ , C.F. ３ CF ２ , (CF ３ ) ２ CF, CF ３ CF ２ CF ２ , C.F. ３ CF ２ CF ２ CF ２ , (CF ３ ) ２ CFCF ２ , C.F. ３ CF ２ (CF ３ ) CF, (CF ３ ) ３ Examples include C.

[0073] A specific example of a preferred fluorinated alkyl fluorophosphate anion is [(CF ３ CF ２ ) ２ PF ４ ]－ [(FF ３ CF ２ ) ３ PF ３ ] － [((CF ３ ) ２ (C) ２ PF ４ ] － [((CF ３ ) ２ (C) ３ PF ３ ] － [(FF ３ CF ２ CF ２ ) ２ PF ４ ] － [(FF ３ CF ２ CF ２ ) ３ PF ３ ] － [((CF ３ ) ２ CFCF ２ ) ２ PF ４ ] － [((CF ３ ) ２ CFCF ２ ) ３ PF ３ ] － [(FF ３ CF ２ CF ２ CF ２ ) ２ PF ４ ] － [[(CF ３ CF ２ CF ２ CF ２ ) ３ PF ３ ] － etc. can be mentioned.

[0074] The photocationic polymerization initiator may be dissolved in advance in a solvent to facilitate dissolution in the epoxy compound or epoxy resin. Examples of the solvent include carbonates such as propylene carbonate, ethylene carbonate, 1,2-butylene carbonate, dimethyl carbonate, and diethyl carbonate.

[0075] One or more of these photocationic polymerization initiators may be selected and used.

[0076] Examples of anion species of the (B) photocationic polymerization initiator include halides such as boron compounds, phosphorus compounds, antimony compounds, arsenic compounds, and alkylsulfonic acid compounds. One or more of these anion species may be selected and used. Among these, fluorides are preferred because they have excellent photocurability and improved adhesiveness and adhesion durability. Among fluorides, hexafluoroantimonate is preferred.

[0077] Among the (B) photocationic polymerization initiators, one or more selected from the group consisting of triarylsulfonium salt hexafluoroantimonate represented by formula (B-2) and diphenyl 4-thiophenoxyphenylsulfonium tris(pentafluoroethyl)trifluorophosphate represented by formula (B-3) are preferred, and triarylsulfonium salt hexafluoroantimonate is more preferred.

[0078]

[0079]

[0080] The content of the (B) cationic photopolymerization initiator is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, and even more preferably 0.5 to 2 parts by mass, relative to 100 parts by mass of the (A) cationic polymerizable compound. When the content of the (B) cationic photopolymerization initiator is 0.05 part by mass or more, the photocurability is further improved, and when it is 5 parts by mass or less, the adhesion durability tends to be further improved.

[0081] (C1) Photosensitizer The encapsulating material for photoelectric conversion elements of this embodiment contains a (C) sensitizer. The (C) sensitizer is preferably a (C1) photosensitizer. The (C1) photosensitizer refers to a compound that absorbs energy rays and efficiently generates cations from the photocationic polymerization initiator.

[0082] The photosensitizer (C1) is not particularly limited, but examples thereof include benzophenone derivatives, phenothiazine derivatives, phenyl ketone derivatives, naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, naphthacene derivatives, chrysene derivatives, perylene derivatives, pentacene derivatives, acridine derivatives, benzothiazole derivatives, benzoin derivatives, fluorene derivatives, naphthoquinone derivatives, anthraquinone derivatives, xanthene derivatives, xanthone derivatives, thioxanthene derivatives, thioxanthone derivatives, coumarin derivatives, ketocoumarin derivatives, cyanine derivatives, azine derivatives, thiazine derivatives, oxazine derivatives, indoline derivatives, azulene derivatives, triallylmethane derivatives, phthalocyanine derivatives, spiropyran derivatives, spirooxazine derivatives, thiospiropyran derivatives, and organic ruthenium complexes. Among these, phenyl ketone derivatives such as 2-hydroxy-2-methyl-1-phenyl-propan-1-one and anthracene derivatives are preferred, and anthracene derivatives are more preferred.

[0083] Examples of anthracene derivatives include anthracene, 1,2-benzanthracene, 9-cyanoanthracene, 9,10-dicyanoanthracene, 2-ethyl-9,10-dimethoxyanthracene, 9,10-dibutoxyanthracene, 9,10-dimethoxyanthracene, 9,10-diethoxyanthracene, 9,10-dipropoxyanthracene, 9,10-diglycidyloxyanthracene, 9,10-bis(phenylethyl)anthracene, etc. Of these, 9,10-diethoxyanthracene is preferred.

[0084] The content of the photosensitizer (C1) is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, and even more preferably 0.1 to 3 parts by mass, relative to 100 parts by mass of the cationically polymerizable compound (A), in terms of not impairing photocurability or decreasing storage stability.

[0085] (D) Phosphate Compound The photoelectric conversion element sealing material of this embodiment may contain (D) a phosphate compound. This tends to reduce viscosity and improve storage stability. As a result, reliability is also likely to be improved. The (D) phosphate compound is at least one selected from the group consisting of (D1) phosphate esters and (D2) phosphites. As the phosphate compound, organic phosphate compounds are preferred, and (D1) phosphate esters are more preferred.

[0086] (D1) Examples of phosphate esters include diethylbenzyl phosphate, trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, tris(butoxyethyl)phosphate, tris(2-ethylhexyl)phosphate (trioctyl phosphate), (RO) ３ Examples of the phosphate phosphate include P═O (R=lauryl, cetyl, stearyl, or oleyl), tris(2-chloroethyl)phosphate, tris(2-dichloropropyl)phosphate, triphenyl phosphate, butyl pyrophosphate, tricresyl phosphate, trixylenyl phosphate, trioctyl phosphate, octyl diphenyl phosphate, cresyl diphenyl phosphate, xylenyl diphosphate, monobutyl phosphate, dibutyl phosphate, di-2-ethylhexyl phosphate, monoisodecyl phosphate, ammonium ethyl acid phosphate, and 2-ethylhexyl acid phosphate salt.

[0087] The (D1) phosphate ester preferably contains at least one selected from the group consisting of a compound represented by formula (D1-1), a compound represented by formula (D1-2), and a compound represented by formula (D1-3), and more preferably contains a compound represented by formula (D1-2).

[0088]

[0089]

[0090]

[0091] In formula (D1-1), formula (D1-2) and formula (D1-3), R １ , R ２ , R ３ , R ４ , R ５ and R ６ each independently represents a hydrocarbon group which may have a substituent.

[0092] R in formula (D1-2) ２ , R ３ and R ４ , and R in formula (D1-3) ５ and R ６ is preferably the same group in each formula.

[0093] R １ , R ２ , R ３ , R ４ , R ５ and R ６ Examples of the substituent that the hydrocarbon group in R may have include an oxyalkyl group. １ , R ２ , R ３ , R ４ , R ５ and R ６ The hydrocarbon group in is preferably an unsubstituted hydrocarbon group.

[0094] R １ , R ２ , R ３ , R ４ , R ５ and R ６ The hydrocarbon group in is preferably an alkyl group or an aryl group, more preferably an alkyl group or a phenyl group, and even more preferably an alkyl group. The number of carbon atoms in the alkyl group may be, for example, 1 to 18, and preferably 4 to 13.

[0095] The compound represented by formula (D1-1) includes, for example, monoalkyl phosphate (i.e., R１ is an alkyl group), and specific examples include monoethyl phosphate, mono-n-butyl phosphate, mono(butoxyethyl) phosphate, mono(2-ethylhexyl) phosphate, and the like.

[0096] The compound represented by formula (D1-2) includes trialkyl phosphate (i.e., R ２ , R ３ and R ４ is an alkyl group). ２ , R ３ and R ４ The alkyl group preferably has 1 to 18 carbon atoms, more preferably 4 to 12 carbon atoms, and even more preferably 8 carbon atoms.

[0097] Specific examples of trialkyl phosphates include triethyl phosphate, tri-n-butyl phosphate, tris(butoxyethyl) phosphate, tris(2-ethylhexyl) phosphate (trioctyl phosphate), (RO) ３ Examples thereof include P=O (wherein R is a lauryl group, a cetyl group, a stearyl group, or an oleyl group).

[0098] The compound represented by formula (D1-3) includes, for example, dialkyl phosphate (i.e., R ５ and R ６ is an alkyl group), etc. Specific examples of dialkyl phosphates include dibutyl phosphate and bis(2-ethylhexyl) phosphate.

[0099] In formula (D1-1), formula (D1-2) and formula (D1-3), R １ , R ２ , R ３ , R ４ , R ５ and R ６ may each independently be one or more of a hydrocarbon group containing an alkyl group, a hydrocarbon group containing an aromatic ring, and a hydrocarbon group containing an aliphatic ring. The hydrocarbon group may have a partially unsaturated group, and may have any atom or substituent. In this case, R １ , R ２ , R３ , R ４ , R ５ and R ６ is preferably a hydrocarbon group containing an alkyl group. The hydrocarbon group is preferably an unsubstituted saturated group. １ , R ２ , R ３ , R ４ , R ５ and R ６ are preferably the same.

[0100] (D2) Examples of phosphite esters include trimethyl phosphite, triethyl phosphite, tri-n-butyl phosphite, tris(2-ethylhexyl) phosphite, triisooctyl phosphite, tridecyl phosphite, triisodecyl phosphite, tris(tridecyl)phosphite, trioleyl phosphite, tristearyl phosphite, triphenyl phosphite, tris(nonylphenyl)phosphite, tris(2,4-di-t-butylphenyl)phosphite, phenyl diisooctyl phosphite, phenyl diisodecyl phosphite, diphenyl mono(2-ethylhexyl) phosphite, diphenyl isooctyl phosphite, diphenyl monodecyl phosphite, diphenyl monoisodecyl phosphite, diphenyl mono(tridecyl)phosphite, bis(nonylphenyl)dinonylphenyl phosphite, tetraphenyl dipropylene glycol diphosphite, poly (dipropylene glycol)phenyl phosphite, diisodecyl pentaerythritol diphosphite, bis(tridecyl)pentaerythritol diphosphite, distearyl pentaerythritol diphosphite, bis(nonylphenyl)pentaerythritol diphosphite, tetraphenyltetra(tridecyl)pentaerythritol tetraphosphite, tetra(tridecyl)-4,4'-isopropylidene diphenyl phosphite, trilauryl trithiophosphite, dimethyl hydrogen phosphite, dibutyl hydrogen phosphite, di(2-ethylhexyl) hydrogen phosphite, dilauryl hydrogen phosphite, dioleyl hydrogen phosphite, diphenyl hydrogen phosphite, diphenyl mono(2-ethylhexyl) phosphite, diphenyl monodecyl phosphite, and diphenyl mono(tridecyl) phosphite.

[0101] The content of the (D) phosphoric acid compound is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, and even more preferably 0.1 to 2 parts by mass, relative to 100 parts by mass of the (A) cationically polymerizable compound. If the content of the (D) phosphoric acid compound is 0.01 part by mass or more, an increase in viscosity after light irradiation can be suppressed and reliability can be improved, and if it is 5 parts by mass or less, good photocurability can be maintained.

[0102] [Others] In addition to the above components (A) to (D), the photoelectric conversion element sealing material may further contain known additives such as a silane coupling agent, an initiator, and a stabilizer such as crown ether.

[0103] ((F1) Stabilizer) By including a (F1) stabilizer, storage stability can be improved. The (F1) stabilizer is not particularly limited, but examples thereof include amino acid derivative compounds such as carbonyldiimidazole, antioxidants, ether compounds, and mixtures thereof. Among these, ether compounds are preferred, and examples thereof include polyalkylene oxides such as polyethylene glycol, polypropylene glycol, and polyoxytetramethylene glycol, and cyclic crown ethers. Of these, it is preferable to use carbonyldiimidazole and crown ethers. The crown ether is not particularly limited, and examples thereof include 12-crown-4, 15-crown-5, 18-crown-6, and dicyclohexano-18-crown-6.

[0104] When the stabilizer (F1) is contained, the content of the stabilizer (F1) is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1 part by mass or more, per 100 parts by mass of the cationically polymerizable compound (A). This can improve storage stability. On the other hand, the upper limit of the content of the stabilizer (F1) is not particularly limited, and may be, for example, 5 parts by mass or less, per 100 parts by mass of the cationically polymerizable compound (A).

[0105] (Silane Coupling Agent) The silane coupling agent is not particularly limited, but examples thereof include γ-chloropropyltrimethoxysilane, vinyltrimethoxysilane, vinyltrichlorosilane, vinyltriethoxysilane, vinyl-tris(β-methoxyethoxy)silane, γ-(meth)acryloxypropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane, and γ-ureidopropyltriethoxysilane. One or more of these silane coupling agents may be selected and used. Among these, one or more selected from the group consisting of β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropyltriethoxysilane, and γ-(meth)acryloxypropyltrimethoxysilane are preferred, and γ-glycidoxypropyltrimethoxysilane is more preferred.

[0106] When a silane coupling agent is contained, the content of the silane coupling agent is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1 part by mass or more, per 100 parts by mass of the (A) cationically polymerizable compound. This allows for good adhesion and adhesion durability. On the other hand, the upper limit of the content of the silane coupling agent is not particularly limited, and may be, for example, 5 parts by mass or less, per 100 parts by mass of the (A) cationically polymerizable compound, or may not contain a silane coupling agent.

[0107] <Dam Material> The dam material of this embodiment contains the above-mentioned photoelectric conversion element encapsulant and (E) inorganic filler. In the dam material, the photoelectric conversion element encapsulant and (E) inorganic filler may be mixed or may be separate. The mixing method is not particularly limited, and the same method as for the photoelectric conversion element encapsulant can be used.

[0108] The dam material of this embodiment is suitable for use as a dam material in the dam-and-fill method. That is, by including the inorganic filler (E), the viscosity and mechanical strength can be improved. A dam can be obtained by curing the dam material of this embodiment by the method described below.

[0109] (E) Inorganic Filler The dam material of this embodiment contains (E) inorganic filler as an essential component. (E) Inorganic filler is a solid component made of an inorganic substance.

[0110] (E) Examples of the inorganic filler include one or more selected from crystalline silica such as quartz, fused silica, and amorphous silica such as colloidal silica, zircon, zirconia, magnesia, olivine, spinel, chamotte, mullite, andalusite, sillimanite, kyanite, talc, kaolin, mica, chromite, mica, pottery stone, obsidian, perlite, glass, frit, diatomaceous earth, rosestone, vermiculite, expanded shale, aluminium shale, graphite, carbon, gilsonite, zinc oxide, calcium oxide, titanium oxide, zinc carbonate, magnesium carbonate, calcium carbonate, silicon carbide, silicon nitride, and boron nitride.

[0111] The inorganic filler may have a hydrophobic surface, for example, by a known method using epoxysilane, aminosilane, (meth)acrylicsilane, vinylsilane, methylchlorosilane, dimethylpolysiloxane, or the like.

[0112] The content of the (E) inorganic filler is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, relative to 100 parts by mass of the (A) cationically polymerizable compound. From the viewpoint of further improving durability and reliability, it is even more preferably 80 parts by mass or more, and particularly preferably 100 parts by mass or more. On the other hand, the content of the (E) inorganic filler is preferably 300 parts by mass or less, more preferably 200 parts by mass or more, relative to 100 parts by mass of the (A) cationically polymerizable compound. This can improve the dischargeability.

[0113] [Viscosity] The viscosity of 0.5 ml of the dam material of this embodiment, measured using a cone-type plate CPA-52Z at 25°C and a rotation speed of 0.7 rpm, is preferably 100,000 mPa·s or more, more preferably 200,000 mPa·s or more, and even more preferably 250,000 mPa·s or more. On the other hand, the viscosity of the dam material is preferably 1,200,000 mPa·s or less, more preferably 800,000 mPa·s or less, and even more preferably 500,000 mPa·s or less. By keeping the viscosity of the dam material within the above numerical range, uneven discharge during discharge can be reduced and the generation of waviness and bubbles can be suppressed.

[0114] 2. Second Embodiment The sealing material for photoelectric conversion elements of this embodiment is used in a dam-and-fill method, contains (A) a cationically polymerizable compound and (B) a photocationic polymerization initiator, and has a contact angle θc of 30° or less 5 seconds after contact with the surface as measured over time by the following procedure i.

[0115] (Procedure i) Prepare alkali-free glass that has been degreased with acetone and then cleaned with ozone for 15 minutes. A syringe filled with the photoelectric conversion element encapsulant is set in a contact angle meter, and a droplet is prepared under the following condition ii. The droplet is then placed on the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Sessile drop method, θ / 2 method Field of view: Wide 2 Droplet volume: 5 μl

[0116] By setting the contact angle θc 5 seconds after contact to the upper limit or less, the wettability of the photoelectric conversion element encapsulant can be improved. As a result, the adhesion between the photoelectric conversion element encapsulant and the substrate can be increased, and the filling ability of the photoelectric conversion element encapsulant within the dam frame can be improved, thereby improving the reliability of devices using the photoelectric conversion element encapsulant of this embodiment. The details of the reasons for this are not clear, but are presumed to be as follows. First, the low contact angle θc 5 seconds after contact is intended to allow the photoelectric conversion element encapsulant to quickly wet and spread immediately after application, resulting in immediate adhesion to the substrate. Therefore, it is presumed that air bubbles are less likely to be trapped, thereby improving the reliability of devices using the photoelectric conversion element encapsulant.

[0117] [Contact Angle] The contact angle θc 5 seconds after contact with the liquid is 30° or less, preferably 25° or less, and more preferably 22° or less. This improves the wettability of the photoelectric conversion element sealing material. On the other hand, the lower limit of the contact angle θc 5 seconds after contact with the liquid is not particularly limited from the viewpoint of obtaining wettability, but from the viewpoint of improving handleability, it may be, for example, 1° or more, or 5° or more.

[0118] Furthermore, in the contact angle over time measured by procedure i, the contact angle θd 30 seconds after contact with the liquid is preferably 20° or less, more preferably 18° or less, and even more preferably 17° or less. This improves the wettability of the sealing material for photoelectric conversion elements. On the other hand, the lower limit of the contact angle θd 30 seconds after contact with the liquid is not particularly limited from the viewpoint of obtaining wettability, but may be, for example, 1° or more, or 3° or more from the viewpoint of improving handleability.

[0119] Furthermore, the ratio of the contact angle θc (°) (θc / θd) to the contact angle θd (°) is preferably 1.0 or more, while the ratio of the contact angle θa (°) (θc / θd) to the contact angle θb (°) is preferably 2.3 or less, more preferably 2.0 or less, and even more preferably 1.7 or less.

[0120] A photoelectric conversion element encapsulant satisfying the above-mentioned contact angle can be realized by selecting the types of components constituting the photoelectric conversion element encapsulant and adjusting the amounts of the components. Specific examples include using (A-1) an alicyclic compound having an epoxy group, or using (C2) a reactive diluent, (D) a phosphoric acid compound, and (F2) a stabilizer, which will be described later, in order to obtain wettability. Furthermore, in order to ensure the desired physical properties of the photoelectric conversion element encapsulant, a method of combining (A-2) an aromatic compound having an epoxy group, (A-3) a glycidyl ether compound, or the like with (A-1) an alicyclic compound having an epoxy group can also be mentioned.

[0121] [Viscosity] The viscosity of 0.5 ml of the photoelectric conversion element encapsulant, measured using a cone-type plate CPA-40Z at 25°C and a rotation speed of 50 rpm, is preferably 50 mPa s or more, more preferably 80 mPa s or more, and even more preferably 100 mPa s or more. On the other hand, the viscosity of the photoelectric conversion element encapsulant is preferably 1,000 mPa s or less, more preferably 800 mPa s or less, and even more preferably 700 mPa s or less.

[0122] The components constituting the sealing material for photoelectric conversion elements will be described below.

[0123] (A) Cationically Polymerizable Compound The sealing material for a photoelectric conversion element of this embodiment contains (A) a cationically polymerizable compound as an essential component. (A) The cationically polymerizable compound is preferably photopolymerizable.

[0124] As the (A) cationically polymerizable compound, the same compounds as those described in the first embodiment can be used.

[0125] In the present embodiment, the content of the alicyclic compound having an epoxy group (A-1) is preferably 20 parts by mass or more, more preferably 30 parts by mass or more, and even more preferably 40 parts by mass or more, per 100 parts by mass of the cationically polymerizable compound (A). This tends to further improve the durability of the cured product. On the other hand, the content of the alicyclic compound having an epoxy group (A-1) is preferably 85 parts by mass or less, more preferably 80 parts by mass or less, and even more preferably 75 parts by mass or less, per 100 parts by mass of the cationically polymerizable compound (A).

[0126] In the present embodiment, when the (A-2) aromatic compound having an epoxy group is contained, the content of the (A-2) aromatic compound having an epoxy group is preferably 10 parts by mass or more, more preferably 15 parts by mass or more, and even more preferably 20 parts by mass or more, per 100 parts by mass of the (A) cationically polymerizable compound. This tends to further improve the durability of the cured product. On the other hand, the upper limit of the content of the (A-2) aromatic compound having an epoxy group is not particularly limited, and may be, for example, 50 parts by mass or less, per 100 parts by mass of the (A) cationically polymerizable compound, or the (A-2) aromatic compound having an epoxy group may not be contained.

[0127] In the present embodiment, when the (A-3) glycidyl ether compound is contained, the content of the (A-3) glycidyl ether compound is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and even more preferably 15 parts by mass or more, per 100 parts by mass of the (A) cationically polymerizable compound. This tends to further improve the durability of the cured product. On the other hand, there is no particular upper limit on the content of the (A-3) glycidyl ether compound, and it may be, for example, 65 parts by mass or less per 100 parts by mass of the (A) cationically polymerizable compound, or the (A-3) glycidyl ether compound may not be contained.

[0128] In the present embodiment, the total content of the alicyclic compound (A-1) having an epoxy group, the aromatic compound (A-2) having an epoxy group, and the glycidyl ether compound (A-3) in 100 parts by mass of the cationically polymerizable compound (A) is preferably 60 parts by mass or more, more preferably 80 parts by mass or more, most preferably 90 parts by mass or more, and even more preferably 100 parts by mass.

[0129] (B) Photocationic Polymerization Initiator The photoelectric conversion element sealing material of this embodiment contains (B) a photocationic polymerization initiator as an essential component. When a photocationic polymerization initiator is used, the photoelectric conversion element sealing material of this embodiment can be cured by irradiation with energy rays such as ultraviolet rays.

[0130] As the (B) photocationic polymerization initiator, the same ones as those explained in the first embodiment can be used.

[0131] In this embodiment, the content of the (B) cationic photopolymerization initiator is preferably 0.05 to 5 parts by mass, more preferably 0.1 to 3 parts by mass, and even more preferably 0.2 to 2 parts by mass, relative to 100 parts by mass of the (A) cationic polymerizable compound. When the content of the (B) cationic photopolymerization initiator is 0.05 parts by mass or more, the photocurability tends to be further improved, and when it is 5 parts by mass or less, the adhesion durability tends to be further improved.

[0132] [(C2) Reactive Diluent] The sealing material for a photoelectric conversion element of this embodiment may contain (C2) a reactive diluent. This tends to reduce the viscosity, which in turn tends to improve reliability.

[0133] Examples of the reactive diluent (C2) include compounds having two or more glycidyl ether functional groups in the aliphatic hydrocarbon chain and a molecular weight of 150 to 600. Furthermore, the reactive diluent may further contain other polymerizable functional groups, for example, alkenyl groups such as vinyl and allyl, or unsaturated groups such as acryloyl and methacryloyl. By setting the molecular weight to be equal to or greater than the above-mentioned lower limit, volatilization of the reactive diluent is suppressed, and good adhesiveness is obtained. On the other hand, by setting the molecular weight to be equal to or less than the above-mentioned lower limit, good reactivity is obtained.

[0134] Examples of the reactive diluent (C2) include diepoxide compounds such as ethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, and cyclohexanedimethanol diglycidyl ether; monoepoxide compounds such as phenyl glycidyl ether and butylphenyl glycidyl ether; and triepoxide compounds such as trimethylolpropane triglycidyl ether and glycerin triglycidyl ether.

[0135] The content of the (C2) reactive diluent is preferably 0.1 to 10 mass %, more preferably 0.5 to 8 mass %, based on the total amount of the photoelectric conversion element encapsulant. By setting the content of the (C2) reactive diluent to be equal to or greater than the above-mentioned lower limit, wettability is improved and good adhesion is obtained. On the other hand, by setting the content of the (C2) reactive diluent to be equal to or less than the above-mentioned upper limit, good strength after curing is obtained and reliability can be improved.

[0136] [(D) Phosphate Compound] The photoelectric conversion element sealing material of this embodiment may contain (D) a phosphate compound. This tends to reduce viscosity and improve storage stability. As a result, reliability is also likely to be improved.

[0137] As the (D) phosphoric acid compound, the same compounds as those described in the first embodiment can be used.

[0138] In this embodiment, the content of the (D) phosphate compound is preferably 0.01 to 5 parts by mass, more preferably 0.05 to 3 parts by mass, and even more preferably 0.1 to 2 parts by mass, relative to 100 parts by mass of the (A) cationically polymerizable compound. If the content of the (D) phosphate compound is 0.01 part by mass or more, an increase in viscosity after light irradiation can be suppressed and reliability can be improved, and if it is 5 parts by mass or less, good photocurability can be maintained.

[0139] [Others] In the present embodiment, the encapsulant for a photoelectric conversion element may further contain, in addition to the above components (A) to (D), known additives such as (F2) a stabilizer, a silane coupling agent, an initiator, a sensitizer, etc. Furthermore, it is preferable that the encapsulant for a photoelectric conversion element of the present embodiment does not contain (E) an inorganic filler.

[0140] [(F2) Stabilizer] The inclusion of a (F2) stabilizer can improve storage stability. Examples of the (F2) stabilizer include, but are not limited to, carboxylic acid amide compounds, antioxidants, ether compounds, amino acid derivative compounds, and mixtures thereof. For example, phosphorus-based antioxidants such as tris(2,4-di-tert-butylphenyl)phosphite, diphenyl mono(2-ethylhexyl)phosphite, diphenyl monodecyl phosphite, pentaerythritol bis(2,6-di-tert-butyl-4-phenyl phosphite), and 2,2'-methylenebis(4,6-di-tert-butylphenyl)-2-ethylhexyl phosphite may be used as the (F2) stabilizer. Examples of ether compounds include polyalkylene oxides such as polyethylene glycol, polypropylene glycol, and polyoxytetramethylene glycol, as well as cyclic crown ethers. Among these, carbonyldiimidazole and crown ethers are preferred. The crown ether is not particularly limited, and examples thereof include 12-crown-4, 15-crown-5, 18-crown-6, and dicyclohexano-18-crown-6.

[0141] When the stabilizer (F2) is contained, the content of the stabilizer (F2) is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1 part by mass or more, per 100 parts by mass of the cationically polymerizable compound (A). This allows for improved storage stability. On the other hand, the upper limit of the content of the stabilizer (F2) is not particularly limited, and may be, for example, 5 parts by mass or less, per 100 parts by mass of the cationically polymerizable compound (A).

[0142] (Silane Coupling Agent) As the silane coupling agent, the same ones as those explained in the first embodiment can be used.

[0143] Hereinafter, the common configuration, characteristics, uses, etc. of the sealing materials for photoelectric conversion elements described in the first and second embodiments will be further described.

[0144] <Applications> The encapsulant for a photoelectric conversion element of this embodiment is preferably used for displays such as liquid crystal displays, organic EL displays, and electronic paper, and for encapsulating photoelectric conversion elements such as silicon solar cells, dye-sensitized solar cells, and organic thin-film solar cells.

[0145] <Manufacturing Method> The manufacturing method of the sealing material for photoelectric conversion elements of this embodiment is not particularly limited as long as the above components can be sufficiently mixed. The method for mixing the components is not particularly limited, but examples include a stirring method that uses the stirring force associated with the rotation of a propeller, and a method that uses a conventional disperser such as a planetary stirrer that rotates and revolves. These mixing methods are preferred because they are low-cost and allow stable mixing.

[0146] <Apparatus> The apparatus of this embodiment includes a photoelectric conversion element sealed with the above-described sealing material for a photoelectric conversion element. An example of the apparatus of this embodiment will be described below with reference to the drawings.

[0147] As shown in Fig. 1, the device 100 of this embodiment includes a photoelectric conversion element 31, a filler material 21 covering the photoelectric conversion element 31, a dam material 22 arranged to surround the filler material 21, and a pair of members (members 11 and 12) that sandwich these. The photoelectric conversion element 31 is also arranged on the member 12. In this embodiment, the dam material 22 is formed using the above-mentioned photoelectric conversion element sealing material and (E) an inorganic filler. The photoelectric conversion element 31 is sealed by the filler material 21 and the dam material 22.

[0148] 2 is a diagram showing the positional relationship between the fill material 21 and the dam material 22 in a plan view of the device 100. As shown in Fig. 2, the fill material 21 is surrounded by the dam material 22. In other words, the side wall of the fill material 21 is in contact with the dam material 22.

[0149] Specific examples of the device 100 include displays such as liquid crystal displays, organic EL displays, and electronic paper, as well as silicon solar cells, dye-sensitized solar cells, and organic thin-film solar cells.

[0150] Next, an example of a manufacturing method of the device 100 of this embodiment will be described. As shown in Fig. 3, the manufacturing method of the device 100 of this embodiment includes the steps of: attaching a filler material 21 and a dam material 22 surrounding the filler material 21 onto a member 11 (first member); embedding a photoelectric conversion element 31 in the filler material 21; arranging a member 12 (second member) so as to cover the filler material 21 and the dam material 22; and curing the filler material 21 so as to bond the members 11 and 12 together, wherein the dam material 22 contains the above-mentioned photoelectric conversion element encapsulant and (E) an inorganic filler.

[0151] Details are explained below.

[0152] (Attachment Process) First, as shown in FIG. 3( a), the fill material 21 and the dam material 22 surrounding the fill material 21 are attached to the member 11. The order in which the fill material 21 and the dam material 22 surrounding the fill material 21 are attached is not particularly limited. The dam material 22 is preferably applied by discharging the dam material 22 using a dispenser while placing it at the desired position. This makes it easier to form a dam with the desired shape. The method for applying the fill material 21 is not particularly limited, but for example, it can be applied in a planar manner within the frame of the dam material 22 using an inkjet method (see FIG. 2).

[0153] The thickness of the dam material 22 and the filler material 21 is not particularly limited as long as they can adequately seal the photoelectric conversion element 31 and can achieve flatness and thinness, but can be, for example, 5 to 10 μm. The member 11 can be a transparent panel that serves as the display surface of the display. Examples of transparent panels include glass and transparent resin.

[0154] The filler material 21 applied to the member 11 may be further photocured (see FIG. 3B). That is, after the filler material 21 is activated by irradiation with light, the photoelectric conversion element 31 is embedded in the filler material 21, and the members 11 and 12 are bonded together. This eliminates the need for the photoelectric conversion element 31 to be exposed to light for activating the filler material 21.

[0155] The light is preferably ultraviolet light. For example, ultraviolet light (UV) is emitted from a high-pressure mercury lamp at 100 mW / cm ２ It is more preferable that the viscosity 10 minutes after irradiation with UV for 30 seconds is less than 5 times the viscosity before UV irradiation.

[0156] (Embedding Process) Next, the photoelectric conversion element 31 is embedded in the fill material 21. The embedding method is not particularly limited, but for example, as shown in FIG. 3( c), the photoelectric conversion element 31 may be embedded in the fill material 21 by preparing the photoelectric conversion element 31 installed on the member 12 in advance and arranging the surface of the member 12 on which the photoelectric conversion element 31 is installed facing the fill material 21 and dam material 22. It is also preferable to embed the photoelectric conversion element 31 before the fill material 21 irradiated with light is completely cured. Furthermore, if the fill material 21 and the dam material 22 are thermosetting, they may be thermally cured by heating rather than by light irradiation.

[0157] (Step of placing member 12 (second member)) As shown in FIG. 3(d), member 12 is placed so as to cover fill material 21 and dam material 22. As a result, member 11 and member 12 are stacked via photoelectric conversion element 31 embedded in fill material 21, fill material 21, and dam material 22. The member 12 may be the same as member 11. Furthermore, member 12 and member 11 may be made of the same material, or may be made of different materials. As described above, member 12 may be placed at the same time as the embedding step.

[0158] (Step of curing the filler material) Next, the members 11 and 12 are bonded together, and the filler material 21 is cured. For example, the filler material 21 may be cured by heating to 60 to 200°C. This can accelerate the curing rate after light irradiation. When used to seal an organic electroluminescence element, the heating temperature is preferably 150°C or less, and more preferably 80°C or less, so as not to damage the organic electroluminescence element. The post-heating temperature is preferably 60°C or more.

[0159] The device 100 can be obtained through the above procedure.

[0160] The light source used in the manufacturing method of the device 100 is not particularly limited, but examples thereof include a halogen lamp, a metal halide lamp, a high-power metal halide lamp (containing indium or the like), a low-pressure mercury lamp, a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a xenon excimer lamp, a xenon flash lamp, a light-emitting diode (hereinafter referred to as an LED), etc. These light sources are preferred in that they can efficiently irradiate energy rays corresponding to the reaction wavelength of each (B) photocationic polymerization initiator.

[0161] The above light sources each have different radiation wavelengths and energy distributions. Therefore, the light source is appropriately selected depending on the reaction wavelength of the photocationic polymerization initiator. Natural light (sunlight) can also be used as a reaction initiation light source.

[0162] The irradiation from the light source may be direct irradiation or focused irradiation using a reflecting mirror, fiber, etc. A low wavelength cut filter, a heat ray cut filter, a cold mirror, etc. may also be used.

[0163] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments.

[0164] In the above embodiment, a sealing material for a photoelectric conversion element used in a dam-and-fill method has been described. However, the composition may contain (A) a cationically polymerizable compound, (B) a photocationic polymerization initiator, and (C) a sensitizer, and the contact angle measured over time by a predetermined procedure i is 35° or more and 90° or less 15 seconds after contact with the liquid. Furthermore, in the above embodiment, a sealing material for a photoelectric conversion element used in a dam-and-fill method has been described. However, the composition may contain (A) a cationically polymerizable compound and (B) a photocationic polymerization initiator, and the contact angle measured over time by a predetermined procedure i is 30° or less 5 seconds after contact with the liquid. In either case, the composition has good wettability and can be used as a dam material and a fill material in a display device, a sealing material for a light-emitting diode element (including an organic electroluminescence display element or a micro LED), or a solar cell (including a perovskite solar cell), etc.

[0165] Although the embodiments of the present invention have been described above with reference to the drawings, these are merely examples of the present invention, and various other configurations can also be adopted.

[0166] Next, the present invention will be described in detail with reference to examples, but the content of the present invention is not limited to the examples.

[0167] <First embodiment of the invention> 1. Raw materials for sealing materials and dam materials for photoelectric conversion elements (A-1) Alicyclic compounds having an epoxy group Alicyclic compound 1 having an epoxy group: (3,3',4,4'-diepoxy)bicyclohexyl "Celloxide 8010" manufactured by Daicel Chemical Industries, Ltd. Alicyclic compound 2 having an epoxy group: 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate "Celloxide 2021P" manufactured by Daicel Chemical Industries, Ltd. (A-2) Aromatic compounds having an epoxy group Aromatic compound 1 having an epoxy group: bisphenol A type epoxy resin, epoxy equivalent 160 to 170 g / eq, "JER-806" manufactured by Mitsubishi Chemical Corporation Aromatic compound 2 having an epoxy group: bisphenol A type epoxy resin, epoxy equivalent 184 to 194 g / eq, "JER-828" manufactured by Mitsubishi Chemical Corporation Aromatic compound 3 having an epoxy group: phenol novolac type multifunctional epoxy, epoxy equivalent 184 to 194 g / eq, "N-775" manufactured by DIC Corporation (A-3) Glycidyl ether compound Glycidyl ether compound 1: dibromophenyl glycidyl ether "BR-250H" manufactured by Nippon Kayaku Co., Ltd. Glycidyl ether compound 2: tetrabromobisphenol A glycidyl ether "Epiclon 153" manufactured by DIC Corporation Glycidyl ether compound 3: phenyl glycidyl ether "PEG" manufactured by Sakamoto Pharmaceutical Co., Ltd. "JP-200" Glycidyl ether compound 4: epoxidized polybutadiene "JP-200" manufactured by Nippon Soda Co., Ltd.

[0168] (B) Photocationic polymerization initiator Photocationic polymerization initiator 1: Triarylsulfonium-tetrakis(pentafluorophenyl)gallate "CPI-310FG" manufactured by San-Apro Co., Ltd. Photocationic polymerization initiator 2: Triarylsulfonium cation-antimony hexafluoride "SP-170" manufactured by ADEKA Corporation

[0169] (C1) Sensitizers Sensitizer 1: 9,10-diethoxyanthracene "DEA" manufactured by Kawasaki Chemical Industries, Ltd. Sensitizer 2: 2-hydroxy-2-methylpropiophenone "DAROCUR1173" manufactured by BASF Japan (formerly Ciba)

[0170] (D) Phosphate Compounds Phosphate Compound 1: Trioctyl Phosphate "TOP" manufactured by Daihachi Chemical Co., Ltd.

[0171] (Others) Stabilizer: Crown ether (18-crown-6) "O-18" manufactured by Nippon Kayaku Co., Ltd. Silane coupling agent: Epoxy group-containing silane coupling agent, γ-glycidoxypropyltrimethoxysilane "KBM-403" manufactured by Shin-Etsu Chemical Co., Ltd.

[0172] (E) Inorganic filler Inorganic filler 1: Fused spherical silica, commercially available product Inorganic filler 2: Flake talc 1 "#5000PA" manufactured by Matsumura Sangyo Co., Ltd. Inorganic filler 3: Flake talc 2 "#5000PJ" manufactured by Matsumura Sangyo Co., Ltd.

[0173] 2. Photoelectric Conversion Element Sealant (A-1) to (A-3), (B), (C1), (D), and other components were mixed in the proportions (parts by mass) shown in Table 1 in a glass container using a metal blade (Teflon-coated) as a stirring blade to prepare photoelectric conversion element sealants for Examples and Comparative Examples. The following measurements were performed using the photoelectric conversion element sealant. [Contact Angle] Using the photoelectric conversion element sealant, the contact angle over time was measured according to the following procedure i, and the contact angle θa 15 seconds after contact with the liquid and the contact angle θb 120 seconds after contact with the liquid were determined. A controller was used for droplet preparation and bubble removal. The results are shown in Table 1. (Procedure i) Alkali-free glass was prepared, degreased with acetone and then ozone-cleaned for 15 minutes. A syringe containing the photoelectric conversion element sealant was set in a contact angle meter, and a droplet was prepared under the following condition ii. The droplet was then placed on the prepared alkali-free glass, and the contact angle over time was measured. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Droplet method, θ / 2 method Field of view: Wide 2 Droplet amount: 5 μl

[0174] The following instruments and devices were used to measure the contact angle: Alkali-free glass: Corning Eagle XG thread surface (manufactured by Test Piece) 0.7 x 100 x 100 mm Ozone cleaning device: "ASM2001N" manufactured by Asumi Giken Co., Ltd. Contact angle measuring device: Dynamic contact angle meter DMo-602, controller DMC-3 (manufactured by Kyowa Interface Science Co., Ltd.)

[0175] [Viscosity-1] Using 0.5 ml of the photoelectric conversion element sealing material, the viscosity was measured using a cone-type plate CPA-52Z at 25°C and a rotation speed of 25 rpm. The measurement was also carried out in an air atmosphere. The results are shown in Table 1.

[0176] 3. Dam material Dam materials were prepared by mixing (A-1) to (A-3), (B), (C1), (D), (E) and other components in the proportions (parts by mass) shown in Table 1 in a glass container using a metal blade (Teflon coated) as a stirring blade. The obtained dam material was subjected to the following measurements and evaluations.

[0177] [Viscosity-2] Using 0.5 ml of dam material, a cone-type plate CPA-52Z was used to measure viscosity at 25°C and a rotation speed of 0.7 rpm. The measurement was performed in an air atmosphere. The results are shown in Table 1.

[0178] The viscosity was measured using the following equipment: Measurement equipment: manufactured by BROOKFIELD

[0179] [Evaluation] A dam material was applied to one surface of a 25 mm square alkali-free glass substrate along a 5 mm inward direction from the outer edge of the substrate using a dispenser, and the dam material was arranged in a rectangular frame. Next, a 25 mm square alkali-free glass substrate was separately prepared and bonded to the dam material under an air pressure of 0.9 MPa, and 6000 mJ / cm was irradiated with a high-pressure mercury lamp. ２ Subsequently, a 1 kg weight was placed on the center of the outermost layer of the substrate, and the dam material was heated and cured at 85°C for 60 minutes to form a dam and bond the substrates together, thereby obtaining a substrate with a dam.

[0180] (1) Variation in dam width The width of the dam material was measured when it was placed in a rectangular frame, and the variation U was calculated from the maximum and minimum dam widths (mm) using the following formula: Variation U = (maximum value - minimum value) / (maximum value + minimum value)

[0181] (2) Appearance of dam width Furthermore, the appearance of the dam material when placed in a rectangular frame was evaluated according to the following criteria: (Criteria) OK: No waviness or foaming was observed NG: Waviness or foaming was observed

[0182] (3) Storage stability of dam width: reliability The obtained substrate with dam was stored under conditions of 85°C and 85% RH, and the dam was observed before and after storage and evaluated according to the following criteria: (Criteria) A: Even after 6 weeks of storage, no peeling was observed at the interface between the dam and the substrate, and reliability was high. B: Even after 1 week of storage, no peeling was observed at the interface between the dam and the substrate, and reliability was high. C: After 1 week of storage, peeling was observed at the interface between the dam and the substrate, and reliability was low.

[0183] In Table 1, "*1" indicates that the viscosity was too high and droplets could not be formed properly.

[0184] <Second embodiment of the invention> 1. Raw materials for sealing materials and dam materials for photoelectric conversion elements (A-1) Alicyclic compounds having an epoxy group Alicyclic compound 1 having an epoxy group: (3,3',4,4'-diepoxy)bicyclohexyl "Celloxide 8010" manufactured by Daicel Chemical Industries, Ltd. Alicyclic compound 2 having an epoxy group: 3',4'-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate "Celloxide 2021P" manufactured by Daicel Chemical Industries, Ltd. (A-2) Aromatic compounds having an epoxy group Aromatic compound 1 having an epoxy group: bisphenol A type epoxy resin, epoxy equivalent 160 to 170 g / eq, "JER-806" manufactured by Mitsubishi Chemical Corporation Aromatic compound 2 having an epoxy group: bisphenol A type epoxy resin, epoxy equivalent 184 to 194 g / eq, "JER-828" manufactured by Mitsubishi Chemical Corporation (A-3) Glycidyl ether compounds Glycidyl ether compound 1: Dibromophenyl glycidyl ether "BR-250H" manufactured by Nippon Kayaku Co., Ltd. Glycidyl ether compound 2: Tetrabromobisphenol A glycidyl ether "Epiclon 153" manufactured by DIC Corporation

[0185] (B) Photocationic polymerization initiators Photocationic polymerization initiator 1: triarylsulfonium-tetrakis(pentafluorophenyl)gallate "CPI-310FG" manufactured by San-Apro Co., Ltd. Photocationic polymerization initiator 2: triarylsulfonium cation-hexafluoride antimony "SP-170" manufactured by ADEKA Corporation Photocationic polymerization initiator 3: benzyl(4-hydroxyphenyl)methylsulfonium hexafluoroantimonate "SI-100" manufactured by Sanshin Chemical Industry Co., Ltd.

[0186] (C2) Reactive diluent Reactive diluent 1: 1,6 hexanediol diglycidyl ether "ED-503G" manufactured by ADEKA Corporation

[0187] (D) Phosphate Compounds Phosphate Compound 1: Trioctyl Phosphate "TOP" manufactured by Daihachi Chemical Co., Ltd.

[0188] (F2) Stabilizers Stabilizer 1: Crown ether (18-crown-6) "O-18" manufactured by Nippon Kayaku Co., Ltd. Stabilizer 2: Carboxylic acid amide "CDI-4309" manufactured by King Industries Co., Ltd. Stabilizer 3: Diphenyl monodecyl phosphite "JPM-331" manufactured by Johoku Chemical Industry Co., Ltd.

[0189] (Others) Silane coupling agent: Epoxy group-containing silane coupling agent, γ-glycidoxypropyltrimethoxysilane "KBM-403" manufactured by Shin-Etsu Chemical Co., Ltd.

[0190] 2. Photoelectric Conversion Element Sealant (A) to (E) and other components were mixed in the proportions (parts by mass) shown in Table 2 in a glass container using a metal blade (Teflon-coated) as a stirring blade to prepare photoelectric conversion element sealants for Examples and Comparative Examples. The following measurements were performed using the photoelectric conversion element sealant. [Contact Angle] Using the photoelectric conversion element sealant, the contact angle over time was measured according to the following procedure i, and the contact angle θc 5 seconds after contact with the liquid and the contact angle θd 30 seconds after contact with the liquid were determined. A controller was used for droplet preparation and bubble removal. The results are shown in Table 1. (Procedure i) Alkali-free glass was prepared by degreasing with acetone and then cleaning with ozone for 15 minutes. A syringe filled with the photoelectric conversion element sealant was set in a contact angle meter, and a droplet was prepared under the following condition ii. The droplet was then placed on the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Droplet method, θ / 2 method Field of view: Wide 2 Droplet amount: 5 μl

[0191] The following instruments and devices were used to measure the contact angle: Alkali-free glass: Corning Eagle XG thread surface (manufactured by Test Piece) 0.7 x 100 x 100 mm Ozone cleaning device: "ASM2001N" manufactured by Asumi Giken Co., Ltd. Contact angle measuring device: Dynamic contact angle meter DMo-602, controller DMC-3 (manufactured by Kyowa Interface Science Co., Ltd.)

[0192] [Viscosity] Using 0.5 ml of the photoelectric conversion element sealing material, the viscosity was measured using a cone-type plate CPA-40Z at 25°C and a rotation speed of 50 rpm. The measurement was carried out in an air atmosphere. The results are shown in Table 2. The viscosity was measured using the following device: Measuring device: manufactured by BROOKFIELD

[0193] 3. Evaluation [Wettability] First, samples were prepared using the following procedure. (1) A glass plate (alkali-free glass; sintered Corning Eagle XG, manufactured by Test Piece) was cut into 5 cm squares, and surface dust was wiped off using acetone degreasing and air blowing. (2) A dam material was applied to the surface of the glass plate to form a 4 cm square frame, and each photoelectric conversion element encapsulant (fill material) prepared in a 16-spot dot pattern was applied within the frame. (3) Inorganic glass was placed to cover the dam material and fill material on the glass plate, and the glass plate and inorganic glass were bonded together in a glove box (dew point approximately -20°C DP) with the dam material and fill material interposed between them. (4) The sample was removed from the glove box and further compressed (-0.02 MPa, 0.1 kN, 30 s) using a press to obtain a sample. Next, the state of the fill material of the obtained sample was observed through the inorganic glass, and evaluated according to the following evaluation criteria. (Evaluation criteria) A: The filler spread evenly (the entire glass surface was wet). B: The filler spread somewhat, but unevenly (there were areas on the glass surface that were not wet, or multiple areas that were not wet). C: The filler did not spread very well (the glass surface was not wet).

[0194] [Reliability] First, organic EL elements were fabricated by the following procedure: Each photoelectric conversion element sealing material (fill material) was applied to glass using a coating device under a nitrogen atmosphere, and the glass was attached to an organic EL element substrate. The adhesive thickness was 10 μm, and the adhesive was applied under 6000 mJ / cm of a high-pressure mercury lamp. ２The resulting composition was cured under photocuring conditions such as light irradiation to prepare an organic EL element. The cathode side of the organic EL element substrate was attached to glass via a photoelectric conversion element encapsulant (fill material). The organic EL element immediately after preparation was then exposed to temperatures of 85°C and relative humidity of 85% by mass for 1000 hours, after which a voltage of 6 V was applied for 10 seconds. The light-emitting state of the organic EL element was observed visually and under a microscope, and the average diameter (μm) of the dark spots was measured and evaluated according to the following criteria. (Criteria) OK: The average diameter (μm) of the dark spots was 300 μm or less. NG: The average diameter (μm) of the dark spots was more than 300 μm.

[0195]

[0196] This application claims priority based on Japanese Patent Application No. 2024-068213 filed on April 19, 2024, and Japanese Patent Application No. 2024-068237 filed on April 19, 2024, the disclosures of which are incorporated herein in their entireties.

[0197] 11 Member 12 Member 21 Filling material 22 Dam material 31 Photoelectric conversion element 100 Device

Claims

1. A photoelectric conversion element encapsulant used in a dam-and-fill method, comprising (A) a cationic polymerizable compound, (B) a photocationic polymerization initiator, and (C) a sensitizer, wherein the contact angle θa 15 seconds after application of the encapsulant is 35° or more and 90° or less, as measured by the following procedure i: (Procedure i) Prepare alkali-free glass that has been degreased with acetone and then cleaned with ozone for 15 minutes. A syringe filled with the photoelectric conversion element encapsulant is set in a contact angle meter, and a droplet is made under the following condition ii. The droplet is then applied to the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Sessile drop method, θ / 2 method Field of view: Wide 2 Droplet volume: 5 μl 2. The photoelectric conversion element encapsulant according to claim 1, wherein the contact angle over time measured by step i is a contact angle θb of 12° or more and 32° or less 120 seconds after application of the liquid.

3. The sealing material for photoelectric conversion elements according to claim 2, wherein the contact angle θa relative to the contact angle θb (θa / θb) is 1.5 or more and 5.0 or less.

4. The encapsulant for photoelectric conversion elements according to any one of claims 1 to 3, wherein the viscosity of 0.5 ml of the encapsulant for photoelectric conversion elements measured using a cone-type plate CPA-52Z at 25°C and a rotation speed of 25 rpm is 2,000 mPa·s or more and 50,000 mPa·s or less.

5. The encapsulant for photoelectric conversion elements according to any one of claims 1 to 4, further comprising (D) a phosphoric acid compound.

6. The photoelectric conversion element encapsulant according to any one of claims 1 to 5, wherein the (A) cationically polymerizable compound contains one or more compounds selected from (A-1) an alicyclic compound having an epoxy group, (A-2) an aromatic compound having an epoxy group, and (A-3) a glycidyl ether compound and derivatives thereof.

7. The encapsulant for photoelectric conversion elements according to any one of claims 1 to 6, further comprising a stabilizer.

8. A dam material comprising the sealing material for photoelectric conversion elements according to any one of claims 1 to 7 and (E) an inorganic filler.

9. The dam material according to claim 8, wherein the content of the inorganic filler (E) is 20 to 300 parts by mass per 100 parts by mass of the cationically polymerizable compound (A).

10. The dam material according to claim 8 or 9, wherein the viscosity of 0.5 ml of the dam material, measured using a cone-type plate CPA-52Z at 25°C and a rotation speed of 0.7 rpm, is 100,000 mPa·s or more and 1,200,000 mPa·s or less.

11. A hardened product of the dam material according to any one of claims 8 to 10.

12. A device comprising a photoelectric conversion element sealed with the dam material according to any one of claims 8 to 10.

13. The device according to claim 12, wherein the photoelectric conversion element is an organic electroluminescence element.

14. A method for manufacturing a device, comprising the steps of: attaching a fill material and a dam material surrounding the fill material onto a first member; embedding a photoelectric conversion element in the fill material; arranging a second member so as to cover the fill material and the dam material; and hardening the fill material so as to bond the first member and the second member together, wherein the dam material is a dam material described in any one of claims 8 to 10.

15. A photoelectric conversion element encapsulant used in the dam-and-fill method, comprising (A) a cationically polymerizable compound and (B) a photocationic polymerization initiator, wherein the contact angle θc 5 seconds after application of the encapsulant is 30° or less when measured by the following procedure i. (Procedure i) Prepare alkali-free glass that has been degreased with acetone and then cleaned with ozone for 15 minutes. A syringe filled with the photoelectric conversion element encapsulant is set in a contact angle meter, and a droplet is made under the following condition ii. The droplet is then applied to the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Droplet method, θ / 2 method Field of view: Wide 2 Droplet volume: 5 μl 16. The photoelectric conversion element encapsulant according to claim 15, wherein the contact angle over time measured by step i is a contact angle θd of 20° or less 30 seconds after application of the liquid.

17. The sealing material for photoelectric conversion elements according to claim 16, wherein the contact angle θc relative to the contact angle θd (θc / θd) is 1.0 or more and 2.3 or less.

18. The encapsulant for photoelectric conversion elements according to any one of claims 15 to 17, wherein the viscosity of 0.5 ml of the encapsulant for photoelectric conversion elements measured using a cone-type plate CPA-40Z at 25°C and a rotation speed of 50 rpm is 50 mPa·s or more and 1,000 mPa·s or less.

19. The encapsulant for photoelectric conversion elements according to any one of claims 15 to 18, further comprising at least one of (C2) a reactive diluent, (D) a phosphoric acid compound, and (F) a stabilizer.

20. A sealing material for photoelectric conversion elements according to any one of claims 15 to 19, wherein the (A) cationically polymerizable compound contains one or more compounds selected from (A-1) an alicyclic compound having an epoxy group, (A-2) an aromatic compound having an epoxy group, and (A-3) a glycidyl ether compound and derivatives thereof.

21. The photoelectric conversion element encapsulant according to any one of claims 15 to 20, which is used as a fill material.

22. A cured product of the sealing material for photoelectric conversion elements according to any one of claims 15 to 21.

23. A device comprising a photoelectric conversion element encapsulated with the photoelectric conversion element encapsulant according to any one of claims 15 to 21.

24. The device according to claim 23, wherein the photoelectric conversion element is an organic electroluminescence element.

25. A method for manufacturing a device, comprising the steps of: attaching a fill material and a dam material surrounding the fill material onto a first member; embedding a photoelectric conversion element in the fill material; arranging a second member so as to cover the fill material and the dam material; and hardening the fill material so as to bond the first member and the second member together, wherein the fill material is a sealing material for a photoelectric conversion element described in any one of claims 15 to 21.

26. A polymerizable composition, the contact angle θa 15 seconds after application of the liquid measured by the following procedure i, being 35° or more and 90° or less. (Procedure i) Prepare alkali-free glass that has been degreased with acetone and then cleaned with ozone for 15 minutes. Set a syringe filled with the polymerizable composition in a contact angle meter, create a droplet under the following condition ii, and apply the droplet to the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Sessile droplet method, θ / 2 method Field of view: Wide 2 Droplet volume: 5 μl 27. A polymerizable composition, wherein the contact angle θc 5 seconds after application of the liquid is 30° or less when measured by the following procedure i. (Procedure i) Prepare alkali-free glass that has been degreased with acetone and then cleaned with ozone for 15 minutes. Set a syringe filled with the polymerizable composition in a contact angle meter, create a droplet under the following condition ii, and apply the droplet to the prepared alkali-free glass to measure the contact angle over time. (Condition ii) Measurement method: Change over time Control method: Standard Analysis technique and method: Sessile droplet method, θ / 2 method Field of view: Wide 2 Droplet volume: 5 μl

Images