Fused thiophene compounds and compositions for forming wavelength-converting films containing the same

Abstract

A ring-fused thiophene compound represented by formula (1) is provided as a novel ring-fused thiophene compound suitable as a phosphor for a wavelength conversion film. (Ar1 and Ar2 each independently represent an aromatic ring which may have a substituent or a heteroarimatic ring which may have a substituent; R1 to R4 each independently represent a hydrogen atom, an alkyl group which may have a substituent, or the like; a case where all of R1 to R4 simultaneously represent hydrogen atoms is excluded; R1 and R2 may be bound to each other to form a ring in conjunction with a nitrogen atom adjacent thereto; R3 and R4 may be bound to each other to form a ring in conjunction with a nitrogen atom adjacent thereto; one or both of R1 and R2 may be bound to Ar1 to form a ring in conjunction with a nitrogen atom adjacent thereto; one or both of R3 and R4 may be bound to Ar2 to form a ring in conjunction with a nitrogen atom adjacent thereto; and one of Y1 and Y2 represents -SO2- and the other represents -S- or -SO2-.)

Description

[Technical Field]

[0001] The present invention relates to fused ring thiophene compounds and wavelength conversion film-forming compositions containing the same. [Background technology]

[0002] MicroLED displays are expected to be the next generation of displays, following LCDs and OLEDs, due to their high contrast and brightness capabilities, as well as their wide range of applications, including large screens and transparent displays. In microLED displays, typically a tiny LED chip is placed for each pixel. One method for arranging these LED chips is the RGB-LED method, which implements three colors of LEDs. However, this method has drawbacks such as the complexity of controlling the LED's light emission and the low performance of the red LED. Therefore, wavelength conversion methods that can solve these problems are attracting attention. The wavelength conversion method uses only blue LED chips, and uses wavelength conversion materials to extract red and green light. This method has the advantage of being able to produce the three primary colors using only blue LED chips.

[0003] Conventionally, technologies using organic light-emitting materials have been proposed as wavelength conversion materials. For example, those using pyridine-phthalimide condensates (Patent Document 1, etc.), those using coumarin derivatives (Patent Document 2, etc.), those using perylene derivatives (Patent Document 3, etc.), those using rhodamine derivatives (Patent Document 4), and those using pyromethene derivatives (Patent Documents 5, 6, etc.) have been disclosed.

[0004] These wavelength conversion materials generally require properties such as good wavelength conversion efficiency, color purity, and lightfastness. In this regard, for example, Patent Document 7 discloses that a composition comprising a binder resin made of a specific methacrylic polymer, a specific fluorescent dye, and a photopolymerizable acrylic acid ester can be used as a high-performance, lightfast red conversion material. Furthermore, techniques for adding light stabilizers to prevent degradation of organic light-emitting materials and improve their durability have also been disclosed (e.g., Patent Document 8). Furthermore, it is known that by adding fine particles to the wavelength conversion material, the optical path length increases due to the scattering of light within the color conversion layer, improving the blue light absorption rate, and the luminescence efficiency is improved by the rescattering of light reflected at the interface (Patent Documents 9, 10, etc.).

[0005] However, with the recent advancements in display technology, there is a growing demand for further improvements in the wavelength conversion efficiency and durability of wavelength conversion materials in compositions for forming wavelength conversion films, from the perspective of improving display performance.

[0006] Furthermore, Patent Document 11 discloses a fused ring thiophene compound having a specific structure, which is a fluorescent dye for staining intracellular lipid droplets. This fused ring thiophene compound has excellent light resistance and possesses absorption and fluorescence maximum wavelengths in the visible light region, making it promising for use as a wavelength conversion material; however, there is room for further improvement in conversion efficiency. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2002-348568 [Patent Document 2] Japanese Patent Publication No. 2007-273440 [Patent Document 3] Japanese Patent Publication No. 2002-317175 [Patent Document 4] Japanese Patent Publication No. 2001-164245 [Patent Document 5] Japanese Patent Publication No. 2011-241160 [Patent Document 6] Japanese Patent Publication No. 2014-136771 [Patent Document 7] Japanese Patent Publication No. 2006-89724 [Patent Document 8] Japanese Patent Publication No. 2011-149028 [Patent Document 9] International Publication No. 2020 / 189678 [Patent Document 10] International Publication No. 2019 / 181698 [Patent Document 11] Japanese Patent Publication No. 2018-145422 [Overview of the Initiative] [Problems that the invention aims to solve]

[0008] The present invention has been made in view of the above circumstances, and aims to provide a novel fused ring thiophene compound suitable as a phosphor for wavelength conversion films, and a wavelength conversion film forming composition containing the fused ring thiophene compound that provides a wavelength conversion film with excellent wavelength conversion efficiency and durability. [Means for solving the problem]

[0009] As a result of diligent research to solve the above problems, the present inventors have found that the above problems can be solved by including a novel fused thiophene compound as the phosphor in a wavelength conversion film-forming composition containing a phosphor and a binder, and have completed the present invention.

[0010] In other words, the present invention provides the following fused ring thiophene compounds and a wavelength conversion film-forming composition containing the same. 1. A fused thiophene compound represented by the following formula (1). [ka] (In the formula, Ar 1 and Ar 2 Each of these is independently an aromatic ring which may have substituents or a heteroaromatic ring which may have substituents, R 1 ~R 4is, independently of one another, a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an aryl group which may have a substituent or a heteroaryl group which may have a substituent, and R 1 ~R 4 will not all simultaneously be hydrogen atoms, R 1 and R 2 may combine with each other to form a ring together with the adjacent nitrogen atom, and R 3 and R 4 may combine with each other to form a ring together with the adjacent nitrogen atom, and R 1 and R 2 either one or both of them may combine with Ar 1 to form a ring together with the adjacent nitrogen atom, and R 3 and R 4 either one or both of them may combine with Ar 2 to form a ring together with the adjacent nitrogen atom, Y 1 and Y 2 are such that one is -SO2- and the other is -S- or -SO2-. ) 2. The above Y 1 and Y 2 is a condensed thiophene compound in which one is -SO2- and the other is -S-. 3. The above Ar 1 and Ar 2 is a condensed thiophene compound of the 1- or 2-ring type in which they are an aromatic ring which may have a substituent or a heteroaromatic ring which may have a substituent. 4. The above R 1 ~R 4 is a condensed thiophene compound of any one of the 1- to 3-ring types in which they are an aryl group which may have a substituent. 5. A composition for forming a wavelength conversion film containing (A) a phosphor composed of the condensed thiophene compound according to any one of the above 1 to 4 and (B) a binder. 6. Further, a composition for forming a wavelength conversion film of 5 containing (C) light-scattering particles. 7. The composition for forming a wavelength conversion film of 6 in which the above (C) light-scattering particles are titanium oxide particles. 8. The above (B) binder is a wavelength conversion film-forming composition containing a resin, one of 5 to 7. 9. The above (B) binder is a wavelength conversion film-forming composition of any of 5 to 7, comprising a polymerizable monomer and a photopolymerization initiator. 10. The above (B) binder is a wavelength conversion film-forming composition of any one of 5 to 7, comprising an alkali-soluble resin, a polymerizable monomer, and a photopolymerization initiator. 11. A wavelength conversion film-forming composition according to any of 5 to 10, wherein the phosphor content of (A) above is 0.1% by mass or more in solid content. 12. A wavelength conversion film-forming composition according to any of 6 to 11, wherein the content of the above (C) light scattering particles is 1% by mass or more in the solid content. 13. A wavelength conversion film-forming composition according to any of 5 to 12, wherein the haze value of the film formed from the above composition is 18% or more. [Effects of the Invention]

[0011] According to the present invention, a novel fused ring thiophene compound suitable as a phosphor for wavelength conversion films can be provided, and a wavelength conversion film forming composition can be provided that gives a wavelength conversion film with excellent wavelength conversion efficiency and durability by using the fused ring thiophene compound. [Modes for carrying out the invention]

[0012] The present invention will be described in more detail below. The fused ring thiophene compound of the present invention is a fused ring thiophene compound represented by the following formula (1).

[0013] [ka]

[0014] In the formula, Ar 1 and Ar 2 Each of these is independently an aromatic ring which may have substituents or a heteroaromatic ring which may have substituents, and R 1 ~R 4Each of these is independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted aryl group, or an optionally substituted heteroaryl group, and R 1 ~R 4 Not all of them become hydrogen atoms at the same time, R 1 and R 2 These may bond to each other and form a ring with adjacent nitrogen atoms, R 3 and R 4 These may bond to each other and form a ring with adjacent nitrogen atoms, R 1 and R 2 Either one or both of them are Ar 1 It may bond with R to form a ring with adjacent nitrogen atoms, 3 and R 4 Either one or both of them are Ar 2 It may bond with adjacent nitrogen atoms to form a ring, Y 1 and Y 2 One of them is -SO2- and the other is -S- or -SO2-.

[0015] Ar 1 and Ar 2 Examples of aromatic rings represented by this formula include the benzene ring as a monocyclic aromatic hydrocarbon ring, and the naphthalene ring, anthracene ring, phenanthrene ring, fluorene ring, pyrene ring, and triphenylene ring as polycyclic aromatic hydrocarbon rings.

[0016] Ar 1 and Ar 2 The aromatic ring represented by may have substituents. Examples of substituents include halogen atoms, alkyl groups, cycloalkyl groups, alkyl halides, aryl groups, heteroaryl groups, cyano groups, and nitro groups, as described below. If substituents are present, the number is preferably 1 to 6, and more preferably 1 to 3.

[0017] Ar 1 and Ar 2Examples of heteroaromatic rings represented by include monocyclic heteroaromatic rings such as pyrrole rings, thiophene rings, furan rings, imidazole rings, pyrazole rings, thiazole rings, oxazole rings, pyridine rings, and pyrazine rings, and polycyclic heteroaromatic rings such as indole rings, isoindole rings, benzimidazole rings, quinoline rings, isoquinoline rings, and quinoxaline rings.

[0018] Ar 1 and Ar 2 The heteroaromatic ring represented by may have substituents. Examples of substituents include halogen atoms, alkyl groups, cycloalkyl groups, alkyl halides, aryl groups, heteroaryl groups, cyano groups, and nitro groups, as described below. When substituents are present, the number of substituents is preferably 1 to 6, and more preferably 1 to 3.

[0019] Among them, Ar 1 and Ar 2 From the viewpoint of increasing the absorption maximum wavelength and fluorescence maximum wavelength and further improving lightfastness, substituted or unsubstituted aromatic rings are preferred, and substituted or unsubstituted monocyclic aromatic hydrocarbon rings are more preferred.

[0020] Examples of halogen atoms include fluorine, chlorine, bromine, and iodine.

[0021] The alkyl group may be linear or branched, and specific examples include alkyl groups having 1 to 10 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group, and tert-butyl group, with alkyl groups having 1 to 6 carbon atoms being preferred.

[0022] The alkyl group described above may have substituents. Examples of substituents include the halogen atom described above, the cycloalkyl group described below, the aryl group described below, the heteroaryl group described below, the cyano group, the nitro group, and so on. If substituents are present, the number is preferably 1 to 6, and more preferably 1 to 3.

[0023] Examples of cycloalkyl groups include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl groups, which have 3 to 10 carbon atoms, with cycloalkyl groups having 4 to 8 carbon atoms being preferred.

[0024] The above cycloalkyl group may have substituents. Examples of substituents include the halogen atom, the alkyl group, the aryl group described later, the heteroaryl group described later, the cyano group, the nitro group, and so on. If substituents are present, the number is preferably 1 to 6, and more preferably 1 to 3.

[0025] Examples of alkyl halogens include trifluoromethyl groups and pentafluoroethyl groups.

[0026] The aryl group may be a monocyclic aryl group, a fused aryl group, or a polycyclic aryl group. Specific examples include the phenyl group as a monocyclic aryl group, the naphthyl group, anthracenyl group, phenantrenyl group, fluorenyl group, pyrenyl group, and triphenylenyl group as fused aryl groups, and aryl groups with 6 to 18 carbon atoms, such as the biphenyl group and terphenyl group, with aryl groups with 6 to 14 carbon atoms being preferred.

[0027] The above aryl group may have substituents. Examples of substituents include the above halogen atom, the above alkyl group, the above aryl group, the heteroaryl group described later, the cyano group, the nitro group, etc. If substituents are present, the number is preferably 1 to 6, and more preferably 1 to 3.

[0028] The heteroaryl group may be either a monocyclic heteroaryl group or a fused heteroaryl group. Examples of monocyclic heteroaryl groups include pyrrolyl, thienyl, furanyl, imidazolyl, pyrazolyl, thiazolyl, oxazolyl, pyridyl, and pyrazyl groups. Examples of fused heteroaryl groups include indolyl, isoindolyl, benzimidazolyl, quinolyl, isoquinolyl, and quinoxalyl groups.

[0029] The heteroaryl group may have substituents. Examples of substituents include the halogen atom, alkyl group, aryl group, heteroaryl group, cyano group, nitro group, etc. If substituents are present, the number is preferably 1 to 6, and more preferably 1 to 3.

[0030] Among them, R 1 and R 2 Preferably, the group is a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, more preferably a substituted or unsubstituted aryl group, and even more preferably an unsubstituted aryl group.

[0031] The above R 1 and R 2 These atoms may bond to each other to form a ring with adjacent nitrogen atoms. 1 and R 2 However, examples of rings formed by bonding with each other and adjacent nitrogen atoms include the following groups:

[0032] [ka]

[0033] Also, the above R 1 and R 2 R 1 and R 2 Either one or both of Ar 1 It may bond with adjacent nitrogen atoms to form a ring. 1 and R 2 Either one or both of them are Ar 1 Examples of rings formed by bonding with adjacent nitrogen atoms include the following groups:

[0034] [ka]

[0035] Also, R 3 and R 4 are preferably a substituted or unsubstituted aryl group or a substituted or unsubstituted heteroaryl group, more preferably a substituted or unsubstituted aryl group, and even more preferably an unsubstituted aryl group.

[0036] The above R 3 and R 4 may combine with each other to form a ring together with the adjacent nitrogen atom. R 3 and R 4 Examples of the ring formed by combining with each other and together with the adjacent nitrogen atom include, for example, the groups shown as specific examples of the ring formed by R 1 and R 2 combining with each other and together with the adjacent nitrogen atom in the above.

[0037] Also, for the above R 3 and R 4 either one or both of R 3 and R 4 may combine with Ar 2 to form a ring together with the adjacent nitrogen atom. Examples of the ring formed by either one or both of R 3 and R 4 combining with Ar 2 and together with the adjacent nitrogen atom include, for example, the groups shown as specific examples of the ring formed by either one or both of R 1 and R 2 combining with Ar 1 and together with the adjacent nitrogen atom in the above. Formed The groups shown as specific examples of the ring can be mentioned.

[0038] In the compound represented by the above formula (1), the bonding position of the group represented by -NR 1 R 2 to Ar 1 , and the bonding position of the group represented by -NR 3 R 4 to Ar 2 are not particularly limited. For example, Ar 1 and Ar 2When it is a benzene ring, the compound represented by the following formula (1’) is likely to be formed.

[0039]

Chemical formula

[0040] In the formula, Y 1 and Y 2 are the same as above. R 1 ~R 4 are each independently a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group which may have a substituent, an aryl group which may have a substituent, or a heteroaryl group which may have a substituent, and not all of R 1 ~R 4 simultaneously become hydrogen atoms. R 1 and R 2 may combine with each other to form a ring together with the adjacent nitrogen atom, R 3 and R 4 may combine with each other to form a ring together with the adjacent nitrogen atom, R 1 and R 2 either one or both of them may combine with the adjacent benzene ring to form a ring together with the adjacent nitrogen atom, and R 3 and R 4 either one or both of them may combine with the adjacent benzene ring to form a ring together with the adjacent nitrogen atom.

[0041] In the above formula (1), Y 1 and Y 2 are such that one is -SO2- and the other is -S- or -SO2-. As for Y 1 and Y 2 , considering the wavelength conversion efficiency of the obtained wavelength conversion film, it is preferable that one is -SO2- and the other is -S-. Also, when the compound represented by the above formula (1) is used as a green light emitter, Y 1 and Y 2Preferably, one is -S- and the other is -SO2-, and when the compound represented by the above formula (1) is used as a red light emitter, Y 1 and Y 2 It is preferable that both are -SO2-.

[0042] As a fused thiophene compound that satisfies the above conditions, the compound represented by the following formula (1-1) is preferred.

[0043] [ka] (In the formula, Ar 1 Ar 2 , R 1 ~R 4 , Y 1 and Y 2 (This is the same as above.)

[0044] Furthermore, compounds represented by the following formulas (1-1A) and (1-2A) are more preferred.

[0045] [ka] (In the formula, Ar 1 and Ar 2 This is the same as above. R 1a ~R 4a Each of these is independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, or an optionally substituted aryl group.

[0046] Equation (1) above in Preferred specific examples of the compounds represented include, for example, the compounds represented by the following formulas (1-1B) and (1-2B).

[0047] [ka]

[0048] Furthermore, the fused ring thiophene compound may also exist as a solvate of the fused ring thiophene compound represented by formula (1), and both are included within the scope of the present invention. The solvate is not particularly limited as long as it is a solvate of the fused ring thiophene compound represented by formula (1) and a solvent. Examples of solvents used to form the solvate include dichloromethane, chloroform, acetonitrile, diethyl ether, ethyl acetate, methanol, ethanol, cyclohexane, toluene, acetone, N,N-dimethylformamide, dimethyl sulfoxide, and tetrahydrofuran.

[0049] The compound represented by formula (1) above not only has excellent light resistance but also excellent conversion efficiency, making it suitable as a phosphor for wavelength conversion materials in display applications.

[0050] The compound represented by formula (1) above can be synthesized by referring to known methods, for example, by a procedure similar to the method described in paragraph

[0084] and subsequent paragraphs of Japanese Patent Application Publication No. 2018-145422.

[0051] The wavelength conversion film-forming composition of the present invention is characterized by containing (A) a phosphor consisting of a fused thiophene compound represented by the above formula (1), and (B) a binder. In the following description, "solid content" refers to components other than the solvent that constitute the wavelength conversion film-forming composition.

[0052] The phosphor content of component (A) described above is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and even more preferably 0.5% by mass or more, considering the wavelength conversion efficiency of the resulting wavelength conversion film. On the other hand, there is no particular upper limit to the phosphor content of component (A), but considering that the fluorescence quantum yield decreases when the phosphor concentration is increased, it is preferably 30% by mass or less, more preferably 10% by mass or less, even more preferably 7% by mass or less, and even more preferably 5% by mass or less, considering the fluorescence quantum yield decreases when the phosphor concentration is increased.

[0053] Furthermore, the wavelength conversion film-forming composition of the present invention may also contain other phosphors as phosphors other than the fused thiophene compound represented by formula (1) above, as long as the effects of the present invention are not impaired. Other phosphors mentioned above include cyanine dyes such as 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran; pyridine dyes such as 1-ethyl-2-[4-(p-dimethylaminophenyl)-1,3-butadienyl]-pyridium-perchlorate; rhodamine dyes such as rhodamine B and rhodamine 6G; red-converting phosphors such as oxazine dyes; coumarin dyes such as 2,3,5,6-1H,4H-tetrahydro-8-trifluoromethylquinolidino(9,9a,1-gh)coumarin, 3-(2'-benzothiazolyl)-7-diethylaminocoumarin, and 3-(2'-benzimidazolyl)-7-N,N-diethylaminocoumarin; and green-converting phosphors such as naphthalimide dyes such as solvent yellow 11 and solvent yellow 116. Other examples include red-converting phosphors or green-converting phosphors such as fused thiophene compounds described in Japanese Patent Publication No. 2018-145422.

[0054] If other phosphors are included, their content is preferably 5% by mass or less, more preferably 2% by mass or less, and even more preferably none (0% by mass).

[0055] The above (B) binder can be selected from known resins and the like that used as binders in wavelength conversion film forming compositions.

[0056] The resin can be appropriately selected from resins used as base resins for wavelength conversion film-forming compositions. Examples include polyolefin resins such as polystyrene (PS), polyethylene (PE), polypropylene (PP), polyester, polyimide, polyamide, and polymethylpentene; acrylic resins such as polymethyl methacrylate (PMMA), methyl methacrylate-methacrylic acid copolymer, and benzyl methacrylate-methacrylic acid copolymer; ethylene-vinyl acetate copolymer (EVA); polyvinyl butyrate (PVB); and cellulose ester resins such as triacetylcellulose (TAC) and nitrocellulose. The above resin may be an alkali-soluble resin as described later, or it may contain both an alkali-soluble resin and other resins. Among these, acrylic resins are preferred, and methyl methacrylate-methacrylic acid copolymers are more preferred. The above resins may be commercially available products, or those obtained by the reaction of unsaturated double bond groups may be synthesized by conventional methods such as radical polymerization using polymerization initiators.

[0057] The average molecular weight of the above resin is not particularly limited, but its weight-average molecular weight (Mw) is usually 5,000 to 100,000, preferably 10,000 to 50,000. In this invention, the average molecular weight is the polystyrene equivalent value obtained by gel permeation chromatography.

[0058] The binder (B) described above may be a mixture of polymerizable monomers and a photopolymerization initiator, which is polymerized after film formation. These can also be used in combination with the resins described above. The polymerizable monomers mentioned above are not particularly limited as long as they are used together with a photopolymerization initiator and polymerize upon irradiation with light, but ethylenically unsaturated monomers are preferred. In the present invention, monofunctional monomers, difunctional monomers, and monomers with three or more functions can be used as the ethylenically unsaturated monomers.

[0059] Examples of monofunctional monomers include mono(meth)acrylates represented by the following formula (M1), mono(meth)acrylamide compounds represented by the following formula (M2), and amide compounds represented by the following formula (M3).

[0060] [ka]

[0061] In equation (M1), R m1 R represents a hydrogen atom or a methyl group. m2 R represents a monovalent hydrocarbon group (excluding those containing an ethylenically unsaturated group). The hydrocarbon group may be linear, branched, or cyclic. The above R is superior in terms of its excellent ejection stability in the inkjet method and its effect on improving external quantum efficiency. m2 The carbon number is preferably 10 or less. The hydrocarbon group may be substituted, for example, it may have an ether bond.

[0062] In equation (M2), R m1 This is the same as above. R m3 and R m4 Each of these independently represents a hydrogen atom and a monovalent hydrocarbon group (excluding those containing ethylenically unsaturated groups). The hydrocarbon group may be linear, branched, or cyclic. Also, R m3 and R m4 These may bond to each other to form a ring. The above R is superior in terms of its excellent ejection stability in the inkjet method and its effect on improving external quantum efficiency. m3 and R m4 The total number of carbon atoms is preferably 10 or less. The hydrocarbon group may be substituted, and may, for example, have an ether bond.

[0063] In equation (M3), R m5 R represents a hydrogen atom or a methyl group. m6R represents a monovalent hydrocarbon group having an ethylenically unsaturated group. The hydrocarbon group may be linear, branched, or cyclic. R is superior in terms of its excellent ejection stability in the inkjet method and its effect on improving external quantum efficiency. m6 The carbon number is preferably 10 or less. The hydrocarbon group may be substituted, for example, it may have an ether bond.

[0064] Specific examples of mono(meth)acrylates represented by the above formula (M1) include methyl(meth)acrylate, ethyl(meth)acrylate, propyl(meth)acrylate, butyl(meth)acrylate, amyl(meth)acrylate, 2-ethylhexyl(meth)acrylate, octyl(meth)acrylate, nonyl(meth)acrylate, dodecyl(meth)acrylate, hexadecyl(meth)acrylate, octadecyl(meth)acrylate, cyclohexyl(meth)acrylate, methoxyethyl(meth)acrylate, butoxyethyl(meth)acrylate, phenoxyethyl(meth)acrylate, nonylphenoxyethyl(meth)acrylate, glycidyl(meth)acrylate, and dimethylaminoethyl(meth)acrylate. Examples include acrylate, diethylaminoethyl (meth)acrylate, ethoxyethoxyethyl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, benzyl (meth)acrylate, phenylbenzyl (meth)acrylate, mono(2-acryloyloxyethyl) succinate, N-[2-(acryloyloxy)ethyl]phthalimide, N-[2-(acryloyloxy)ethyl]tetrahydrophthalimide, etc.

[0065] Specific examples of mono(meth)acrylamide compounds represented by the above formula (M2) include 4-(meth)acryloylmorpholine, (meth)acrylamide, N-methyl(meth)acrylamide, N,N-dimethyl(meth)acrylamide, N-ethyl(meth)acrylamide, N,N-diethyl(meth)acrylamide, N-isopropyl(meth)acrylamide, and N,N-diisopropyl(meth)acrylamide.

[0066] Specific examples of amide compounds represented by the above formula (M3) include N-vinylformamide, N-vinylacetamide, N-allylformamide, and N-allylacetamide.

[0067] In the present invention, among the monofunctional monomers mentioned above, ethoxyethoxyethyl (meth)acrylate, N-vinylformamide, 4-(meth)acryloylmorpholine, N,N-dimethylacrylamide, and N,N-diethyl (meth)acrylamide are preferably used.

[0068] As monofunctional monomers, those with a viscosity of 10,000 mPa·s or less, more preferably 8,000 mPa·s or less, even more preferably 5,000 mPa·s or less, and still more preferably 1,000 mPa·s or less are preferred, as they easily improve ejection stability in the inkjet method. In this specification, the viscosity of monomers having an ethylenically unsaturated group, such as monofunctional monomers, is the viscosity at 25°C measured, for example, by an EMS viscometer. However, when using a mixture of multiple monomers, high-viscosity monomers can also be suitably used by combining them with low-viscosity monomers. Furthermore, high-viscosity monomers can also be suitably used when used with a solvent.

[0069] Examples of difunctional monomers include di(meth)acrylates represented by the following formula (M4) and di(meth)acrylamide compounds represented by the following formula (M5).

[0070] [ka]

[0071] In equation (M4), multiple R m7 Each of these independently represents a hydrogen atom or a methyl group, R m8 This represents a divalent hydrocarbon group (excluding those containing an ethylenically unsaturated group). The divalent hydrocarbon group may be linear, branched, or cyclic. From the viewpoint of excellent discharge stability and superior effect on improving external quantum efficiency, the number of carbon atoms in the divalent hydrocarbon group is preferably 10 or less. The divalent hydrocarbon group may be substituted, for example, it may have an ether bond.

[0072] In equation (M5), multiple R m9 Each of these independently represents a hydrogen atom or a methyl group, and multiple R m10 Each independently represents a hydrogen atom and a monovalent hydrocarbon group (excluding those containing ethylenically unsaturated groups). The monovalent hydrocarbon group may be linear, branched, or cyclic. The above R is superior in terms of its excellent ejection stability in the inkjet method and its effect on improving external quantum efficiency. m10 The number of carbon atoms is preferably 7 or less. The above monovalent hydrocarbon group may be substituted, for example, it may have an ether bond. m11 This represents a divalent hydrocarbon group (excluding those containing an ethylenically unsaturated group). The divalent hydrocarbon group may be linear, branched, or cyclic. From the viewpoint of excellent discharge stability and superior effect on improving external quantum efficiency, the number of carbon atoms in the divalent hydrocarbon group is preferably 10 or less. The divalent hydrocarbon group may be substituted, for example, it may have an ether bond.

[0073] Specific examples of di(meth)acrylates represented by the above formula (M4) include 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,5-pentanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, tricyclodecanedimethanol di(meth)acrylate, ethylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate. (meth)acrylate, propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, neopentyl glycol hydroxypivalate diacrylate, di(meth)acrylate in which two hydroxyl groups of tris(2-hydroxyethyl) isocyanurate are replaced by (meth)acryloyloxy groups, di(meth)acrylate in which two hydroxyl groups of a diol obtained by adding 4 moles or more of ethylene oxide or propylene oxide to 1 mole of neopentyl glycol are replaced by (meth)acryloyloxy groups, bisphenol A Examples include di(meth)acrylates obtained by adding 2 moles of ethylene oxide or propylene oxide to 1 mole of diol, in which two hydroxyl groups of the diol are substituted with (meth)acryloyloxy groups; di(meth)acrylates obtained by adding 3 or more moles of ethylene oxide or propylene oxide to 1 mole of trimethylolpropane, in which two hydroxyl groups of the triol are substituted with (meth)acryloyloxy groups; and di(meth)acrylates obtained by adding 4 or more moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A, in which two hydroxyl groups of the diol are substituted with (meth)acryloyloxy groups.

[0074] Specific examples of the di(meth)acrylamide compound represented by the above formula (M5) include N,N-[oxybis(2,1-ethanediyloxy-3,1-propanediyl)]bisacrylamide. The above di(meth)acrylamide compound may be a commercially available product, and a specific example of such is FOM-03008 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0075] In the present invention, among the difunctional monomers mentioned above, dipropylene glycol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 1,8-octanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, and 1,10-decanediol di(meth)acrylate are preferably used.

[0076] As for the bifunctional monomer, it is preferable to use one with a viscosity of 10,000 mPa·s or less, more preferably 8,000 mPa·s or less, even more preferably 5,000 mPa·s or less, and still more preferably 1,000 mPa·s or less, as this improves the ejection stability in the inkjet method. The above viscosity is the viscosity at 25°C. However, when using a mixture of multiple monomers, monomers with high viscosity can also be suitably used by combining them with monomers with low viscosity. Furthermore, monomers with high viscosity can also be suitably used when used with a solvent.

[0077] Examples of monomers with three or more functionalities include tri(meth)acrylate, tetra(meth)acrylate, penta(meth)acrylate represented by the following formula (M6), tri(meth)acrylamide compounds represented by the following formula (M7), and tetra(meth)acrylamide compounds.

[0078] [ka]

[0079] In equation (M6), multiple R m12Each of these independently represents a hydrogen atom or a methyl group, R m13 This represents a trivalent hydrocarbon group (excluding those containing an ethylenically unsaturated group). The trivalent hydrocarbon group may be linear, branched, or cyclic. From the viewpoint of excellent discharge stability and superior effect on improving external quantum efficiency, the number of carbon atoms in the hydrocarbon group is preferably 10 or less, more preferably 5 or less. The trivalent hydrocarbon group may be substituted, for example, it may have an ether bond.

[0080] In equation (M7), multiple R m14 Each of these independently represents a hydrogen atom or a methyl group, and multiple R m15 Each independently represents a hydrogen atom and a monovalent hydrocarbon group (excluding those containing ethylenically unsaturated groups). The monovalent hydrocarbon group may be linear, branched, or cyclic. The above R is superior in terms of its excellent ejection stability in the inkjet method and its effect on improving external quantum efficiency. m15 The number of carbon atoms is preferably 7 or less. The above monovalent hydrocarbon group may be substituted, for example, it may have an ether bond. Multiple R m16 Each of these independently represents a divalent hydrocarbon group (excluding those containing an ethylenically unsaturated group). The divalent hydrocarbon group may be linear, branched, or cyclic. From the viewpoint of excellent discharge stability and superior effect on improving external quantum efficiency, the number of carbon atoms in the divalent hydrocarbon group is preferably 10 or less. The divalent hydrocarbon group may be substituted, for example, it may have an ether bond.

[0081] Specific examples of tri(meth)acrylates represented by the above formula (M6) include glycerin tri(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolpropane triacrylate, and pentaerythritol triacrylate.

[0082] Specific examples of the above-mentioned tetra(meth)acrylates include pentaerythritol tetraacrylate and ditrimethylolpropane tetraacrylate.

[0083] Specific examples of the penta(meth)acrylates mentioned above include dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate.

[0084] Specific examples of the tri(meth)acrylamide compound represented by the above formula (M7) include N,N-bis(2-acrylamideethyl)acrylamide. The above tri(meth)acrylamide compound may be a commercially available product, and a specific example of such is FOM-03007 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0085] Specific examples of the above tetra(meth)acrylamide compounds include N-[tris(3-acrylamidepropoxymethyl)methyl]acrylamide, N,N-1,2-ethanediylbis{N-[2-(acryloylamino)ethyl]acrylamide}, etc. Commercially available tetra(meth)acrylamide compounds may also be used, with specific examples including FOM-03006 and FOM-03009 (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.).

[0086] In the present invention, among the three- or more functional monomers mentioned above, glycerin tri(meth)acrylate, dipentaerythritol pentaacrylate, and dipentaerythritol hexaacrylate are preferably used.

[0087] As for the trifunctional monomer, it is preferable to have a viscosity of 10,000 mPa·s or less, more preferably 8,000 mPa·s or less, even more preferably 5,000 mPa·s or less, and still more preferably 1,000 mPa·s or less, as this improves the ejection stability in the inkjet method. The above viscosity is the viscosity at 25°C. However, when using a mixture of multiple monomers, high-viscosity monomers can also be suitably used by combining them with low-viscosity monomers. Furthermore, when using with a solvent, high-viscosity monomers can also be suitably used.

[0088] As photopolymerization initiators, photoradical polymerization initiators, photocationic polymerization initiators, etc., can be used. Considering compatibility with general manufacturing methods for wavelength conversion members, it is preferable to use photoradical polymerizable compounds. On the other hand, from the viewpoint of being able to form a cured film (cured product of the wavelength conversion film forming composition) without oxygen inhibition in the curing process, it is preferable to use photocationic polymerizable compounds.

[0089] As photoradical polymerization initiators, molecular cleavage type or hydrogen abstraction type photoradical polymerization initiators are preferably used.

[0090] Examples of molecular cleavage-type photoradical polymerization initiators include benzoin isobutyl ether, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, ethyl phenyl(2,4,6-trimethylbenzoyl)phosphinate, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, and (2,4,6-trimethylbenzoyl)ethoxyphenylphosphine oxide. Other molecular cleavage-type photoradical polymerization initiators that may be used in combination include, for example, 1-hydroxycyclohexylphenyl ketone, benzoin ethyl ether, benzyldimethyl ketal, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2,2-dimethoxy-2-phenylacetophenone, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, and 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one.

[0091] Examples of hydrogen abstraction-type photoradical polymerization initiators include benzophenone, 4-phenylbenzophenone, isophthalphenone, and 4-benzoyl-4'-methyl-diphenyl sulfide. A molecular cleavage-type photoradical polymerization initiator and a hydrogen abstraction-type photoradical polymerization initiator may be used in combination.

[0092] Photoradical polymerization initiators are also available commercially. Such commercially available products include acylphosphine oxide compounds such as Omnirad (registered trademark; hereinafter the same) TPO-H, Omnirad TPO-L, and Omnirad 819 from IGM Resin; alkylphenone compounds such as Omnirad 651, Omnirad 184, Omnirad 1173, Omnirad 2959, Omnirad 127, Omnirad 907, Omnirad 369, Omnirad 369E, and Omnirad 379EG; intramolecular hydrogen abstraction compounds such as Omnirad MBF and Omnirad 754 from BASF Japan; and Irgacure (registered trademark; hereinafter the same) OXE01, Irgacure OXE02, Irgacure OXE03, and Irgacure Examples of oxime ester compounds include OXE04, TR-PBG-304 and TR-PBG-305 from Changzhou Strong Electronic New Materials Co., Ltd., and NCI-831 and NCI-930 from ADEKA Corporation.

[0093] Other examples of oxime ester compounds include those described in Japanese Patent Publication No. 2004-534797, Japanese Patent Application Publication No. 2000-80068, International Publication No. 2012 / 45736, International Publication No. 2015 / 36910, Japanese Patent Application Publication No. 2006-36750, Japanese Patent Application Publication No. 2008-179611, International Publication No. 2009 / 131189, Japanese Patent Publication No. 2012-526185, Japanese Patent Publication No. 2012-519191, International Publication No. 2006 / 18973, International Publication No. 2008 / 78678, and Japanese Patent Application Publication No. 2011-132215.

[0094] When using a photoradical polymerization initiator as a photopolymerization initiator, a chain transfer agent may be used in combination. Using a chain transfer agent can increase the reaction rate of the photoradical reaction.

[0095] Chain transfer agents are defined on pages 683-684 of the Polymer Dictionary, Third Edition (edited by the Society of Polymer Science, Japan, 2005). Examples of chain transfer agents include compounds having SH, PH, SiH, and GeH groups in their molecules. These can generate radicals by donating hydrogen to low-activity radical species, or by being oxidized and then deprotonated. Thiol compounds (e.g., 2-mercaptobenzimidazoles, 2-mercaptobenzuthiazoles, 2-mercaptobenzuxazoles, 3-mercaptotriazoles, 5-mercaptotetrazoles, etc.) are particularly preferred, and polyfunctional thiol compounds are especially preferred. As polyfunctional thiols, any compound having two or more thiol (SH) groups is acceptable. Examples of polyfunctional thiol compounds include ethylene glycol bisthiopropionate (EGTP), butanediol bisthiopropionate (BDTP), trimethylolpropane tristhiopropionate (TMTP), pentaerythritol tetrakisthiopropionate (PETP), tetraethylene glycol bis(3-mercaptopropionate), dipentaerythritol hexakis(3-mercaptopropionate), pentaerythritol tetrakis(thioglycolate), Karenz (registered trademark, hereinafter the same) MT BD1, Karenz MT PE1, Karenz MT NR1 (all manufactured by Showa Denko K.K.), etc.

[0096] Examples of photocationic polymerization initiators include polyarylsulfonium salts such as triphenylsulfonium hexafluoroantimonate and triphenylsulfonium hexafluorophosphate; and polyaryliodonium salts such as diphenyliodonium hexafluoroantimonate and p-nonylphenyliodonium hexafluoroantimonate.

[0097] Photocationic polymerization initiators can also be obtained commercially. Examples of such commercially available products include sulfonium salt-based photocationic polymerization initiators such as CPI-100P from Sunapro Co., Ltd., Omnicat (registered trademark; hereinafter the same) 270 from IGM Resin, and Irgacure 290 from BASF Japan; and iodonium salt-based photocationic polymerization initiators such as Omnicat 250 from IGM Resin.

[0098] From the viewpoint of the curability of the composition, the content of the above-mentioned photopolymerization initiator is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, and even more preferably 1% by mass or more, based on 100% by mass of the polymerizable monomer. Furthermore, from the viewpoint of film-forming properties and the transparency, heat resistance, and light resistance of the cured film, the upper limit of its content is preferably 40% by mass or less, more preferably 30% by mass or less, and even more preferably 20% by mass or less.

[0099] When polymerizable monomers and photopolymerization initiators are combined, an alkali-soluble resin may also be added. By incorporating an alkali-soluble resin into the wavelength conversion film-forming composition of the present invention, it can be used as a composition for forming resist films.

[0100] In the present invention, an alkali-soluble resin is a resin having alkali-soluble groups. Specific examples of alkali-soluble groups include phenolic hydroxyl groups, carboxyl groups, acid anhydride groups, imide groups, sulfonyl groups, phosphoric acid, boronic acid groups, and activated methylene groups.

[0101] An active methylene group is a methylene group (-CH2-) that has a carbonyl group adjacent to it and exhibits reactivity with nucleophiles.

[0102] As the active methylene group, the group represented by the following formula (b1) is more preferred.

[0103] [ka] (In the formula, R b(The symbols represent alkyl groups, alkoxy groups, or phenyl groups, and the dashed lines represent bonding bonds.)

[0104] In the above equation (b1), R b Examples of alkyl groups represented by include alkyl groups having 1 to 20 carbon atoms, with alkyl groups having 1 to 5 carbon atoms being preferred. Specific examples of such alkyl groups include methyl, ethyl, n-propyl, and i-propyl groups. Among these, methyl, ethyl, and n-propyl groups are preferred.

[0105] In the above equation (b1), R b Examples of alkoxy groups represented by include alkoxy groups having 1 to 20 carbon atoms, with alkoxy groups having 1 to 5 carbon atoms being preferred. Specific examples of such alkoxy groups include methoxy, ethoxy, n-propoxy, i-propoxy, n-butoxy, i-butoxy, s-butoxy, and t-butoxy groups. Among these, methoxy, ethoxy, and n-propoxy groups are preferred.

[0106] Specific examples of the group represented by formula (b1) above include, but are not limited to, the groups represented by formulas (b1-1) to (b1-5) below. In the structural formulas, dashed lines represent bonds.

[0107] [ka]

[0108] Among the alkali-soluble groups mentioned above, it is preferable that the alkali-soluble resin has at least one organic group selected from the group consisting of phenolic hydroxyl groups and carboxyl groups, and has a number-average molecular weight of 2,000 to 50,000.

[0109] As described above, the alkali-soluble resin is preferably one with a number-average molecular weight in the range of 2,000 to 50,000. However, if the number-average molecular weight is 50,000 or less, development residue is less likely to occur, and the required sensitivity can be obtained. On the other hand, if the number-average molecular weight is 2,000 or more, film thinning in the exposed area is less likely to occur during development, and sufficient curability can be obtained.

[0110] The alkali-soluble resin described above only needs to have the above structure, and is not particularly limited in terms of the backbone of the main chain and the type of side chains of the polymer constituting the resin.

[0111] Examples of the alkali-soluble resins mentioned above include acrylic resins, polyhydroxystyrene resins, polyimide precursors, polyimides, or polyesters.

[0112] Furthermore, in the present invention, an alkali-soluble resin consisting of a copolymer obtained by polymerizing multiple types of monomers can also be used. Moreover, the alkali-soluble resin may be a blend of multiple types of alkali-soluble resins.

[0113] As the alkali-soluble resin mentioned above, an acrylic polymer, which is an acrylic resin, can be used. In the present invention, an acrylic polymer refers to a resin obtained by the polymerization reaction of monomers having unsaturated double bond groups, in which the unsaturated double bond group portion reacts. Examples of alkali-soluble acrylic polymers include copolymers formed using monomers that exhibit alkali solubility, i.e., monomers having at least one selected from the aforementioned alkali-soluble groups, and at least one monomer selected from the group of monomers copolymerizable with these monomers, as essential structural units. The number-average molecular weight of the above alkali-soluble resin is preferably 2,000 to 50,000. If the number-average molecular weight is 50,000 or less, residue is less likely to be generated.

[0114] The above-mentioned "monomers having at least one selected from alkali-soluble groups" include monomers having a carboxyl group, a phenolic hydroxyl group, and an imide group. These monomers are not limited to having one carboxyl group or phenolic hydroxyl group, but may also have multiple groups.

[0115] The following are specific examples of the above monomers, but they are not limited to these. Examples of monomers having a carboxyl group include acrylic acid, methacrylic acid, crotonic acid, mono-(2-(acryloyloxy)ethyl) phthalate, mono-(2-(methacryloyloxy)ethyl) phthalate, N-(carboxyphenyl)maleimide, N-(carboxyphenyl)methacrylamide, and N-(carboxyphenyl)acrylamide.

[0116] Examples of monomers having a phenolic hydroxyl group include hydroxystyrene, N-(hydroxyphenyl)acrylamide, N-(hydroxyphenyl)methacrylamide, N-(hydroxyphenyl)maleimide, and 4-hydroxyphenyl methacrylate.

[0117] Examples of monomers having an imide group include maleimide.

[0118] In the production of the alkali-soluble acrylic polymer described above, the ratio of alkali-soluble groups to monomers having unsaturated double bond groups is preferably 5 to 90 mol%, more preferably 10 to 60 mol%, and most preferably 10 to 40 mol% of all monomers used in the production of the alkali-soluble acrylic polymer. Sufficient alkali solubility can be obtained when the ratio of alkali-soluble groups to monomers having unsaturated double bond groups is 10% by mass or more.

[0119] The above alkali-soluble acrylic polymer may be further copolymerized with a monomer having a hydroxyalkyl group and an unsaturated double bond group in order to further stabilize the pattern shape after curing.

[0120] Specific examples of monomers having a hydroxyalkyl group and an unsaturated double bond group include 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 2,3-dihydroxypropyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 2,3-dihydroxypropyl methacrylate, glycerin monomethacrylate, and 5-acryloyloxy-6-hydroxynorbornene-2-carboxylic-6-lactone.

[0121] In the production of the above alkali-soluble acrylic polymer, the ratio of monomers having a hydroxyalkyl group and an unsaturated double bond group is preferably 10 to 60% by mass, more preferably 15 to 50% by mass, and even more preferably 20 to 40% by mass. When the ratio of monomers having a hydroxyalkyl group and an unsaturated double bond group is 10% by mass or more, a stabilizing effect on the pattern shape of the copolymer is obtained. When the ratio is 60% by mass or less, the content of alkali-soluble groups is within an appropriate range, and sufficient developability and other properties are obtained.

[0122] The above alkali-soluble acrylic polymer may be further copolymerized with an N-substituted maleimide compound to increase the Tg of the copolymer.

[0123] Specific examples of N-substituted maleimide compounds include N-methylmaleimide, N-ethylmaleimide, N-phenylmaleimide, and N-cyclohexylmaleimide. From the viewpoint of transparency, compounds without aromatic rings are preferred, and from the viewpoint of developability, transparency, and heat resistance, compounds having an alicyclic skeleton are more preferred, with cyclohexylmaleimide being even more preferred.

[0124] In the production of the above alkali-soluble acrylic polymer, the ratio of N-substituted maleimide is preferably 10 to 60% by mass, more preferably 15 to 50% by mass, and even more preferably 20 to 40% by mass. When the ratio of N-substituted maleimide is 10% by mass or more, the Tg of the copolymer increases, and therefore the Tg of the wavelength conversion film obtained in the end also increases, resulting in sufficient heat resistance and light resistance. When the ratio is 60% by mass or less, sufficient transparency is obtained.

[0125] Furthermore, in the present invention, the alkali-soluble acrylic polymer may be a copolymer containing monomers other than those described above (hereinafter referred to as "other monomers") as constituent units. Specifically, the other monomers are not particularly limited as long as they are copolymerizable with at least one selected from the group consisting of monomers having a carboxyl group and monomers having a phenolic hydroxyl group, as long as the properties of the alkali-soluble acrylic polymer are not impaired. Specific examples of such monomers include acrylic acid ester compounds, methacrylic acid ester compounds, acrylamide compounds, acrylonitrile, styrene compounds, and vinyl compounds. The following are some specific examples of such other monomers, but are not limited to these.

[0126] Specific examples of the above acrylic acid ester compounds include methyl acrylate, ethyl acrylate, isopropyl acrylate, benzyl acrylate, naphthyl acrylate, anthyl acrylate, anthyl methyl acrylate, phenyl acrylate, glycidyl acrylate, phenoxyethyl acrylate, 2,2,2-trifluoroethyl acrylate, tert-butyl acrylate, cyclohexyl acrylate, isobornyl acrylate, 2-methoxyethyl acrylate, and methoxytriethylene glycol acrylate. Examples include rilate, 2-ethoxyethyl acrylate, 2-aminoethyl acrylate, tetrahydrofurfuryl acrylate, 3-methoxybutyl acrylate, 2-methyl-2-adamantyl acrylate, 2-propyl-2-adamantyl acrylate, 8-methyl-8-tricyclodecyl acrylate, 8-ethyl-8-tricyclodecyl acrylate, diethylene glycol monoacrylate, caprolactone 2-(acryloyloxy)ethyl ester, and poly(ethylene glycol) ethyl ether acrylate.

[0127] Specific examples of the above methacrylate ester compounds include methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, benzyl methacrylate, naphthyl methacrylate, anthlyl methacrylate, anthlyl methyl methacrylate, phenyl methacrylate, glycidyl methacrylate, phenoxyethyl methacrylate, 2,2,2-trifluoroethyl methacrylate, tert-butyl methacrylate, cyclohexyl methacrylate, isobornyl methacrylate, 2-methoxyethyl methacrylate, methoxytriethylene glycol methacrylate, Examples include 2-ethoxyethyl methacrylate, 2-aminomethyl methacrylate, tetrahydrofurfuryl methacrylate, 3-methoxybutyl methacrylate, 2-methyl-2-adamantyl methacrylate, γ-butyrolactone methacrylate, 2-propyl-2-adamantyl methacrylate, 8-methyl-8-tricyclodecyl methacrylate, 8-ethyl-8-tricyclodecyl methacrylate, diethylene glycol monomethacrylate, caprolactone 2-(methacryloyloxy)ethyl ester, and poly(ethylene glycol) ethyl ether methacrylate.

[0128] Specific examples of the above acrylamide compounds include N-methylacrylamide, N-methylmethacrylamide, N,N-dimethylacrylamide, N,N-dimethylmethacrylamide, N-methoxymethylacrylamide, N-methoxymethylmethacrylamide, N-butoxymethylacrylamide, and N-butoxymethylmethacrylamide.

[0129] Specific examples of the vinyl compounds mentioned above include, for example, methyl vinyl ether, benzyl vinyl ether, cyclohexyl vinyl ether, vinyl naphthalene, vinyl anthracene, vinyl carbazole, allyl glycidyl ether, 3-ethenyl-7-oxabicyclo[4.1.0]heptane, 1,2-epoxy-5-hexene, and 1,7-octadiene monoepoxide.

[0130] Examples of the styrene compounds mentioned above include styrene without a hydroxyl group. Specific examples include styrene, α-methylstyrene, chlorostyrene, and bromostyrene.

[0131] In the production of the alkali-soluble acrylic polymer described above, the ratio of the other monomers is preferably 80% by mass or less, more preferably 50% by mass or less, and even more preferably 20% by mass or less. When the ratio of the other monomers is 80% by mass or less, the effects of the present invention can be fully obtained.

[0132] The method for obtaining the above-mentioned alkali-soluble acrylic polymer is not particularly limited, but for example, it can be obtained by polymerizing it at a temperature of 50 to 110°C in a solvent containing: a monomer having at least one selected from the group consisting of a carboxyl group, a phenolic hydroxyl group, a group that generates a carboxylic acid by the action of heat or acid, and a group that generates a phenolic hydroxyl group by the action of heat or acid; a monomer having a hydroxyalkyl group; optionally, a monomer having at least one group selected from crosslinkable groups such as N-alkoxymethyl group, N-hydroxymethyl group, alkoxysilyl group, epoxy group, oxetane group, vinyl group, and blocked isocyanate group, and self-crosslinkable groups such as N-alkoxymethyl group, N-hydroxymethyl group, alkoxysilyl group, epoxy group, vinyl group, and blocked isocyanate group; optionally, other copolymerizable monomers; and optionally, a polymerization initiator. The solvent used is not particularly limited as long as it dissolves the monomers constituting the alkali-soluble acrylic polymer and the alkali-soluble acrylic polymer. Specific examples include the following solvents.

[0133] Examples of solvents used in the above reaction include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, methyl cellosolve acetate, ethyl cellosolve acetate, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, propylene glycol propyl ether acetate, toluene, xylene, methyl ethyl ketone, cyclopentanone, cyclohexanone, 2-butanone, and 3-methyl-2-pentanone. Examples include 2-pentanone, 2-heptanone, γ-butyrolactone, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, ethyl ethoxyacetate, ethyl hydroxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, ethyl 3-ethoxypropionate, methyl 3-ethoxypropionate, methyl pyruvate, ethyl pyruvate, ethyl acetate, butyl acetate, ethyl lactate, butyl lactate, N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone. Among these, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, 2-heptanone, propylene glycol propyl ether, propylene glycol propyl ether acetate, ethyl lactate, and butyl lactate are preferred from the viewpoint of good film-forming properties and high safety. These may be used individually or in combination of two or more.

[0134] The alkali-soluble acrylic polymer obtained in this way is usually in the form of a solution dissolved in a solvent.

[0135] Furthermore, the solution of the specific copolymer obtained as described above can be added to a stirring solution such as diethyl ether or water to reprecipitate it. After filtering and washing the resulting precipitate, the specific copolymer can be dried at room temperature or under atmospheric pressure or reduced pressure to obtain a powder. This operation removes polymerization initiators and unreacted monomers coexisting with the specific copolymer, resulting in a purified powder of the specific copolymer. If sufficient purification is not achieved in a single operation, the obtained powder can be redissolved in a solvent and the above operation can be repeated. In the present invention, the powder of the specified copolymer may be used as is, or the powder may be redissolved in a suitable solvent, for example, the solvent used in the polymerization reaction described above, and used in solution form.

[0136] Furthermore, as the alkali-soluble resin mentioned above, polyimides such as polyamic acid, polyamic acid esters, polyimide precursors such as partially imidized polyamic acid, and carboxylic acid group-containing polyimides can also be used, and as long as they are alkali-soluble, their type is not particularly limited.

[0137] The polyamic acid described above, which is a polyimide precursor, can generally be obtained by polycondensation of (a) a tetracarboxylic dianhydride and (b) a diamine compound.

[0138] The above (a) tetracarboxylic dianhydride is not particularly limited, and specific examples include aromatic tetracarboxylic acids such as pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-diphenylethertetracarboxylic dianhydride, and 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride, as well as 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1,2-dimethyl-1,2,3,4-cyclo Examples include alicyclic tetracarboxylic dianhydrides such as butanetetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3,4-cyclohexanetetracarboxylic dianhydride, and 3,4-dicarboxy-1,2,3,4-tetrahydro-1-naphthalenesuccinic acid dianhydride, as well as aliphatic tetracarboxylic dianhydrides such as 1,2,3,4-butanetetracarboxylic dianhydride. These may be used individually or in combination of two or more.

[0139] Furthermore, the above (b) diamine compounds are not particularly limited, and specific examples include 2,4-diaminobenzoic acid, 2,5-diaminobenzoic acid, 3,5-diaminobenzoic acid, 4,6-diamino-1,3-benzenedicarboxylic acid, 2,5-diamino-1,4-benzenedicarboxylic acid, bis(4-amino-3-carboxyphenyl) ether, bis(4-amino-3,5-dicarboxyphenyl) ether, bis(4-amino-3-carboxyphenyl) sulfone, bis(4-amino-3,5-dicarboxyphenyl) sulfone, and 4,4'-diamino-3,3'-dicarboxybif phenyl, 4,4'-diamino-3,3'-dicarboxy-5,5'-dimethylbiphenyl, 4,4'-diamino-3,3'-dicarboxy-5,5'-dimethoxybiphenyl, 1,4-bis(4-amino-3-carboxyphenoxy)benzene, 1,3-bis(4-amino-3-carboxyphenoxy)benzene, bis[4-(4-amino-3-carboxyphenoxy)phenyl]sulfone, bis[4-(4-amino-3-carboxyphenoxy)phenyl]propane, 2,2-bis[4-(4-amino-3-carboxyphenoxy)phenyl]hexafluoropropane; 2,4-diaminophenol, 3,5-diaminophenol, 2,5-diaminophenol, 4,6-diaminoresorcinol, 2,5-diaminohydroquinone, bis(3-amino-4-hydroxyphenyl) ether, bis(4-amino-3-hydroxyphenyl) ether, bis(4-amino-3,5-dihydroxyphenyl) ether, bis(3-amino-4-hydroxyphenyl)methane, bis(4-amino-3-hydroxyphenyl)methane, bis(4-amino-3,5-dihydroxyphenyl)methane, bis(3-amino-4-hydroxyphenyl)sulfone, bis(4-amino-3-hydroxyphenyl)sulfone, bis(4-amino-3,5-dihydroxyphenyl)sulfone, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, 2,2-bis(4-amino-3-hydroxyphenyl)hexafluoropropane, 2,2-bis(4- Diamine compounds having phenolic hydroxyl groups, such as amino-3,5-dihydroxyphenyl)hexafluoropropane, 4,4'-diamino-3,3'-dihydroxybiphenyl, 4,4'-diamino-3,3'-dihydroxy-5,5'-dimethylbiphenyl, 4,4'-diamino-3,3'-dihydroxy-5,5'-dimethoxybiphenyl, 1,4-bis(3-amino-4-hydroxyphenoxy)benzene, 1,3-bis(3-amino-4-hydroxyphenoxy)benzene, 1,4-bis(4-amino-3-hydroxyphenoxy)benzene, 1,3-bis(4-amino-3-hydroxyphenoxy)benzene, bis[4-(3-amino-4-hydroxyphenoxy)phenyl]sulfone, bis[4-(3-amino-4-hydroxyphenoxy)phenyl]propane, and 2,2-bis[4-(3-amino-4-hydroxyphenoxy)phenyl]hexafluoropropane; Examples include diamine compounds having a thiophenol group, such as 1,3-diamino-4-mercaptobenzene, 1,3-diamino-5-mercaptobenzene, 1,4-diamino-2-mercaptobenzene, bis(4-amino-3-mercaptophenyl) ether, and 2,2-bis(3-amino-4-mercaptophenyl)hexafluoropropane; and diamine compounds having a sulfonic acid group, such as 1,3-diaminobenzene-4-sulfonic acid, 1,3-diaminobenzene-5-sulfonic acid, 1,4-diaminobenzene-2-sulfonic acid, bis(4-aminobenzene-3-sulfonic acid) ether, 4,4'-diaminobiphenyl-3,3'-disulfonic acid, and 4,4'-diamino-3,3'-dimethylbiphenyl-6,6'-disulfonic acid. Also, p-phenylenediamine, m-phenylenediamine, 4,4'-methylene-bis(2,6-ethylaniline), 4,4'-methylene-bis(2-isopropyl-6-methylaniline), 4,4'-methylene-bis(2,6-diisopropylaniline), 2,4,6-trimethyl-1,3-phenylenediamine, 2,3,5,6-tetramethyl-1,4-phenylenediamine, o-tolidine, m-tolidine, 3,3',5,5'-tetramethylbenzidine, bis[4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]hexafluoropropane, 4,4'-diamino-3,3'-dimethyldicyclohexyl Examples of diamine compounds include rumethane, 4,4'-diaminodiphenyl ether, 3,4-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 2,2-bis(4-anilino)hexafluoropropane, 2,2-bis(3-anilino)hexafluoropropane, 2,2-bis(3-amino-4-toluyl)hexafluoropropane, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, bis[4-(4-aminophenoxy)phenyl]sulfone, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, and 2,2'-bis(trifluoromethyl)benzidine.These may be used individually or in combination of two or more types.

[0140] When the above polyamic acid is produced from (a) a tetracarboxylic dianhydride and (b) a diamine compound, the ratio of the two compounds, i.e., the total number of moles of the diamine compound (b) / the total number of moles of the tetracarboxylic dianhydride (a), is preferably 0.7 to 1.2. As with typical polycondensation reactions, the closer this molar ratio is to 1, the higher the degree of polymerization of the resulting polyamic acid and the greater the molecular weight.

[0141] Furthermore, when polymerizing using an excess of a diamine compound, the terminal amino groups of the remaining polyamic acid can be protected by reacting them with a carboxylic acid anhydride. Examples of such carboxylic acid anhydrides include phthalic anhydride, trimellitic anhydride, maleic anhydride, naphthalic anhydride, hydrogenated phthalic anhydride, methyl-5-norbornene-2,3-dicarboxylic acid anhydride, itaconic anhydride, and tetrahydrophthalic anhydride.

[0142] In the production of polyamic acid, the reaction temperature for the reaction between the diamine compound and the tetracarboxylic dianhydride can be selected from any temperature, usually between -20 and 150°C, preferably between -5 and 100°C. To obtain high molecular weight polyamic acid, the reaction temperature can be appropriately selected from 5 to 40°C and the reaction time from 1 to 48 hours. To obtain a low molecular weight polyamic acid with high storage stability and partial imidization, it is more preferable to select a reaction temperature of 40 to 90°C and a reaction time of 10 hours or more. Furthermore, when protecting the terminal amino group with an acid anhydride, the reaction temperature can be selected from any temperature between -20 and 150°C, preferably between -5 and 100°C.

[0143] The reaction between diamine compounds and tetracarboxylic dianhydrides can be carried out in a solvent. Suitable solvents include N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, N-vinylpyrrolidone, N-methylcaprolactam, dimethyl sulfoxide, tetramethylurea, pyridine, dimethyl sulfone, hexamethyl sulfoxide, m-cresol, γ-butyrolactone, ethyl acetate, butyl acetate, ethyl lactate, methyl 3-methoxypropionate, methyl 2-methoxypropionate, ethyl 3-methoxypropionate, ethyl 2-methoxypropionate, ethyl 3-ethoxypropionate, ethyl 2-ethoxypropionate, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, and diethylene glycol diethyl ether. Examples include diethylene glycol methyl ethyl ether, propylene glycol dimethyl ether, dipropylene glycol dimethyl ether, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, propylene glycol monomethyl ether acetate, carbitol acetate, ethyl cellosolve acetate, cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, 2-heptanone, etc. These may be used individually or in combination of two or more. Furthermore, even solvents that do not dissolve polyamic acid may be mixed with the above solvents as long as the polyamic acid produced by the polymerization reaction does not precipitate.

[0144] The solution containing the polyamic acid obtained in this manner can be used directly in the preparation of a negative-type photosensitive resin composition. Alternatively, the polyamic acid can be precipitated and isolated in a poor solvent such as water, methanol, or ethanol, and then recovered for use.

[0145] Furthermore, any polyimide can be used as the alkali-soluble resin. The polyimide used in this invention is obtained by chemically or thermally imidizing a polyimide precursor such as the polyamic acid mentioned above by 50% or more.

[0146] The above polyimide preferably has a group selected from a carboxyl group and a phenolic hydroxyl group in order to provide alkali solubility. Methods for introducing carboxyl groups or phenolic hydroxyl groups into polyimides include using monomers having carboxyl groups or phenolic hydroxyl groups, sealing the amine ends with acid anhydrides having carboxyl groups or phenolic hydroxyl groups, and reducing the imidation rate to 99% or less when imidizing polyimide precursors such as polyamic acids.

[0147] Such polyimides can be obtained by synthesizing polyimide precursors such as the polyamic acid mentioned above, followed by chemical or thermal imidation. Generally, chemical imidation involves adding excess acetic anhydride and pyridine to a polyimide precursor solution and reacting it at room temperature to 100°C. Alternatively, thermal imidation generally involves heating the polyimide precursor solution at 180-250°C while simultaneously dehydrating it.

[0148] Furthermore, a phenol novolac resin can be used as the alkali-soluble resin.

[0149] Furthermore, polyester polycarboxylic acid can also be used as the alkali-soluble resin. Polyester polycarboxylic acid can be obtained from an acidic dianhydride and a diol by the method described in International Publication No. 2009 / 051186. Examples of acidic dianhydrides include the tetracarboxylic dianhydride (a) mentioned above. Examples of diols include aromatic diols such as bisphenol A, bisphenol F, 4,4'-dihydroxybiphenyl, benzene-1,3-dimethanol, and benzene-1,4-dimethanol; alicyclic diols such as hydrogenated bisphenol A, hydrogenated bisphenol F, 1,4-cyclohexanediol, 1,3-cyclohexanedimethanol, and 1,4-cyclohexanedimethanol; and aliphatic diols such as ethylene glycol, propylene glycol, 1,4-butanediol, and 1,6-hexanediol.

[0150] The alkali-soluble resin of the present invention is preferably a copolymer that further has a self-crosslinking group or a group that reacts with at least one group selected from the group consisting of a hydroxyl group, a carboxyl group, an amide group, and an amino group (hereinafter also referred to as a crosslinking group).

[0151] Specific examples of the self-crosslinking groups mentioned above include N-alkoxymethyl groups, N-hydroxymethyl groups, alkoxysilyl groups, epoxy groups, oxetane groups, vinyl groups, and blocked isocyanate groups.

[0152] Specific examples of the above-mentioned crosslinkable groups include N-alkoxymethyl groups, N-hydroxymethyl groups, alkoxysilyl groups, epoxy groups, vinyl groups, and blocked isocyanate groups.

[0153] When such self-crosslinking groups or crosslinking groups are included in an alkali-soluble resin, the content is preferably 0.1 to 0.9 groups per repeating unit in the alkali-soluble resin, and more preferably 0.1 to 0.8 groups from the viewpoint of developability and solvent resistance.

[0154] If the alkali-soluble resin further has repeating units having at least one selected from the above-mentioned crosslinkable group and self-crosslinkable group, for example, in the case of an alkali-soluble acrylic polymer, it is possible to copolymerize it with an unsaturated compound that has radical polymerizability and further has at least one selected from the above-mentioned crosslinkable group and self-crosslinkable group.

[0155] Specific examples of the unsaturated compound having radical polymerizability and further having an N-alkoxymethyl group include N-butoxymethylacrylamide, N-isobutoxymethylacrylamide, N-methoxymethylacrylamide, N-methoxymethylmethacrylamide, N-methylolacrylamide and the like.

[0156] Specific examples of the monomer having radical polymerizability and further having a hydroxymethylamide group include N-hydroxymethylacrylamide, N-hydroxymethylmethacrylamide and the like.

[0157] Specific examples of the monomer having radical polymerizability and further having an alkoxysilyl group include 3-acryloyloxytrimethoxysilane, 3-acryloyloxytriethoxysilane, 3-methacryloyloxytrimethoxysilane, 3-methacryloyloxytriethoxysilane and the like.

[0158] Specific examples of the unsaturated compound having radical polymerizability and further having an epoxy group include glycidyl acrylate, glycidyl methacrylate, glycidyl α-ethylacrylate, glycidyl α-n-propylacrylate, glycidyl α-n-butylacrylate, 3,4-epoxybutyl acrylate, 3,4-epoxybutyl methacrylate, 6,7-epoxyheptyl acrylate, 6,7-epoxyheptyl methacrylate, 6,7-epoxyheptyl α-ethylacrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether and the like. Among these, glycidyl methacrylate, 6,7-epoxyheptyl methacrylate, o-vinylbenzyl glycidyl ether, m-vinylbenzyl glycidyl ether, p-vinylbenzyl glycidyl ether, 3,4-epoxycyclohexyl methacrylate are preferred. These may be used alone or in combination of two or more.

[0159] Examples of unsaturated compounds that have radical polymerization properties and also contain an oxetane group include (meth)acrylic acid esters containing an oxetane group. Specific examples of such monomers include 3-(methacryloyloxymethyl)oxetane, 3-(acryloyloxymethyl)oxetane, 3-(methacryloyloxymethyl)-3-ethyl-oxetane, 3-(acryloyloxymethyl)-3-ethyl-oxetane, 3-(methacryloyloxymethyl)-2-trifluoromethyloxetane, 3-(acryloyloxymethyl)-2-trifluoromethyloxetane, 3-(methacryloyloxymethyl)-2-phenyl-oxetane, 3-(acryloyloxymethyl)-2-phenyl-oxetane, 2-(methacryloyloxymethyl)oxetane, 2-(acryloyloxymethyl)oxetane, 2-(methacryloyloxymethyl)-4-trifluoromethyloxetane, and 2-(acryloyloxymethyl)-4-trifluoromethyloxetane. Among these, 3-(methacryloyloxymethyl)-3-ethyl-oxetane and 3-(acryloyloxymethyl)-3-ethyl-oxetane are preferred.

[0160] Specific examples of monomers that have radical polymerization properties and also contain a vinyl group include 2-(2-vinyloxyethoxy)ethyl acrylate and 2-(2-vinyloxyethoxy)ethyl methacrylate.

[0161] Specific examples of monomers that have radical polymerizability and also have a blocked isocyanate group include 2-(0-(1'-methylpropyleneneamino)carboxyamino)ethyl methacrylate and 2-(3,5-dimethylpyrazolyl)carbonylamino)ethyl methacrylate.

[0162] In the alkali-soluble resin of the present invention, the content of a constituent unit derived from an unsaturated compound having radical polymerizability and at least one group selected from the above-mentioned crosslinkable group and self-crosslinkable group is preferably 10 to 70% by mass, more preferably 20 to 60% by mass, of all repeating units of the alkali-soluble resin. When the content of this constituent unit is 10% by mass or more, the heat resistance and surface hardness of the cured film are improved. On the other hand, when the content of this constituent unit is 70% by mass or less, the storage stability of the radiation-sensitive resin composition is improved.

[0163] When the alkali-soluble resin of the present invention is used in combination with the polymerizable monomer described above, it is preferable that the alkali-soluble resin has substituents that can react with the polymerizable monomer. The method for obtaining an alkali-soluble resin having substituents that can react with polymerizable monomers is not particularly limited as long as it yields a resin with stable properties. Examples include copolymerizing monomers having substituents that can react with polymerizable monomers, and synthesizing an alkali-soluble resin without substituents that can react with polymerizable monomers, and then adding a compound having substituents that can react with polymerizable monomers by thermal reaction. When the alkali-soluble resin is an alkali-soluble acrylic polymer, the former method may cause the substituents that can react with polymerizable monomers to react during the polymerization process, leading to gelation. Therefore, synthesis by the latter method is preferred.

[0164] Specifically, one method involves adding glycidyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate, etc., to an alkali-soluble acrylic polymer synthesized using a monomer that has radical polymerizability and further contains a carboxyl group or a phenolic hydroxyl group. In this case, by reducing the molar ratio of the monomer added to the carboxyl group or phenolic hydroxyl group in the resin, it is possible to introduce substituents that can react with polymerizable monomers while maintaining the alkali solubility of the resin derived from the carboxyl group or phenolic hydroxyl group. Another example is a method of adding monomers having substituents that can react with polymerizable monomers capable of thermally reacting with thermally reactive groups in the resin to an alkali-soluble acrylic polymer obtained by copolymerizing monomers that have radical polymerizability and also have thermally reactive groups. Specifically, this involves adding (meth)acrylic acid, (meth)acrylic acid 2-carboxyethyl to an alkali-soluble acrylic polymer obtained by copolymerizing glycidyl methacrylate, 3,4-epoxycyclohexylmethyl methacrylate, etc. In the alkali-soluble resin of the present invention, the proportion of repeating units having substituents that can react with polymerizable monomers is preferably 5 to 60% by mass, more preferably 10 to 50% by mass, and even more preferably 10 to 40% by mass, of all repeating units in the alkali-soluble resin. When the content of these constituent units is 5% by mass or more, the heat resistance and chemical resistance of the cured film are improved. On the other hand, when the content of these constituent units is 60% by mass or less, the pattern-forming properties of the radiation-sensitive resin composition are improved.

[0165] Furthermore, in the present invention, the alkali-soluble resin may be a mixture of multiple types of alkali-soluble resins.

[0166] When using the above-mentioned alkali-soluble resin, its content is preferably 10% by mass or more, more preferably 20% by mass or more, and even more preferably 30% by mass or more, based on 100% by mass of the total of the polymerizable monomer and the alkali-soluble resin, from the viewpoint of film-forming properties. Furthermore, the upper limit of its content is preferably 90% by mass or less, more preferably 80% by mass or less, and even more preferably 70% by mass or less, from the viewpoint of pattern-forming properties.

[0167] The content of the above (B) binder is preferably 70 to 99.9% by mass of the solid content, more preferably 85 to 99.9% by mass, and even more preferably 90 to 99% by mass.

[0168] The wavelength conversion film forming composition of the present invention may further contain (C) light scattering particles. The light scattering particles have the function of scattering light that enters the wavelength conversion film within the film, thereby substantially extending the optical path length in the wavelength conversion film and improving the light absorption rate, and further scattering the light that is reflected at the interface of the wavelength conversion film and returns into the wavelength conversion film, thereby improving the luminescence efficiency.

[0169] The above-mentioned light scattering particles can be appropriately selected depending on the purpose, and may be organic or inorganic fine particles. Of these, inorganic fine particles with a high refractive index are preferred in order to enhance the scattering performance of the particles.

[0170] Examples of the above-mentioned organic fine particles include polymethyl methacrylate beads, acrylic-styrene copolymer beads, melamine beads, polycarbonate beads, styrene beads, cross-linked polystyrene beads, polyvinyl chloride beads, and benzoguanamine-melamineformaldehyde beads.

[0171] Examples of the above inorganic fine particles include inorganic oxide particles consisting of at least one oxide selected from silicon, zirconium, titanium, indium, zinc, antimony, cerium, niobium, tungsten, etc. Specifically, examples of the above inorganic oxide particles include SiO2, ZrO2, TiO2 (hereinafter sometimes referred to as titanium oxide particles), BaTiO3, In2O3, ZnO, Sb2O3, ITO, CeO2, Nb2O5, and WO3. Of these, TiO2, BaTiO3, ZrO2, CeO2, and Nb2O5 are preferred, and TiO2 is more preferred. Furthermore, among TiO2, the rutile type is preferred over the anatase type because it has lower catalytic activity, resulting in higher film durability, and also has a higher refractive index.

[0172] These particles may also be surface-treated. When performing surface treatment, specific materials for surface treatment include different inorganic oxides such as silicon oxide and zirconium oxide, metal hydroxides such as aluminum hydroxide, organosiloxanes, organic acids such as stearic acid, and the like. These surface treatment materials may be used alone or in combination of multiple types.

[0173] The average particle diameter of the light-scattering particles is more than 50 nm and less than 200 nm. From the perspective of wavelength conversion efficiency, the lower limit of the average particle diameter is preferably 60 nm or more, more preferably 70 nm or more. In addition to the perspective of wavelength conversion efficiency, considering the patterning characteristics, from the perspective that the total light reflectance at i-line (365 nm) is low, an average particle diameter exceeding 100 nm is more preferable. If the upper limit of the average particle diameter is too large, it is likely to sediment. Therefore, from the perspective of the storage stability of the composition, it is preferably 190 nm or less, more preferably 180 nm or less. The average particle diameter of the light-scattering particles is the average particle diameter obtained from transmission electron microscope observation.

[0174] Commercially available products may be used as the light-scattering particles. For example, specific examples of titanium oxide particles include PT-401M (rutile type, average particle diameter 70 nm), PT-401L (rutile type, average particle diameter 130 nm), PT-501R (rutile type, average particle diameter 180 nm), etc., but are not limited thereto. The average particle diameter of the exemplified light-scattering particles may have a variation of ±10 nm.

[0175] Considering the wavelength conversion efficiency, the content of the above (C) light-scattering particles is preferably 0.1 to 20% by mass in the solid content, more preferably 0.2 to 15% by mass, and even more preferably 0.3 to 10% by mass.

[0176] In addition to the above components (A) and (B), the composition for forming a wavelength conversion film of the present invention may contain various known additives such as component (C), a light stabilizer, an antioxidant, a surfactant, a polymer dispersant, a flame retardant, a clarifying agent, an ultraviolet absorber, a crosslinking agent, a filler, etc., as required.

[0177] As the surfactant, fluorine-based surfactants are preferred, and nonionic fluorine-based surfactants are more preferred. Specific examples include, but are not limited to, the F-Tergent series manufactured by Neos Corporation, such as the 212M, 215M, 250, 222F, FTX-218, and DFX-18. When a surfactant is used, there are no particular restrictions on the amount it is added, but it is preferably 0.01 to 1% by mass, and more preferably 0.01 to 0.5% by mass, of the solid content of the wavelength conversion film-forming composition.

[0178] The polymeric dispersant is a polymer compound having a weight-average molecular weight of 750 or more and having a functional group that has affinity for light-scattering particles. The polymeric dispersant has the function of dispersing light-scattering particles. The polymeric dispersant is adsorbed onto the light-scattering particles via the functional group that has affinity for the light-scattering particles, and the light-scattering particles are dispersed in the composition by electrostatic repulsion and / or steric repulsion between the polymeric dispersants. It is preferable that the polymeric dispersant is adsorbed onto the light-scattering particles by binding to their surface, but it may also be free in the wavelength conversion film-forming composition.

[0179] Examples of functional groups that have affinity for light scattering particles include acidic functional groups, basic functional groups, and nonionic functional groups. Acidic functional groups have dissociable protons and may be neutralized by bases such as amines and hydroxide ions, while basic functional groups may be neutralized by acids such as organic acids and inorganic acids.

[0180] Examples of acidic functional groups include carboxyl groups (-COOH), sulfo groups (-SO3H), sulfate groups (-OSO3H), phosphonic acid groups (-PO(OH)2), phosphate groups (-OPO(OH)2), phosphinic acid groups (-PO(OH)-), and mercapto groups (-SH).

[0181] Basic functional groups include primary amino groups, secondary amino groups, tertiary amino groups, ammonium groups, and imino groups, as well as nitrogen-containing heterocyclic groups such as pyridine, pyrimidine, pyrazine, imidazole, and triazole.

[0182] Examples of nonionic functional groups include hydroxyl groups, ether groups, thioether groups, sulfinyl groups (-SO-), sulfonyl groups (-SO2-), carbonyl groups, formyl groups, ester groups, carbonate ester groups, amide groups, carbamoyl groups, ureido groups, thioamide groups, thioureido groups, sulfamoyl groups, cyano groups, alkenyl groups, alkynyl groups, phosphine oxide groups, and phosphine sulfide groups.

[0183] The polymeric dispersant may be a polymer (homopolymer) of a single monomer, or a copolymer of multiple monomers. Furthermore, the polymeric dispersant may be a random copolymer, a block copolymer, or a graft copolymer. If the polymeric dispersant is a graft copolymer, it may be a comb-shaped graft copolymer or a star-shaped graft copolymer. Specific examples of polymeric dispersants include acrylic resins, polyester resins, polyurethane resins, polyamide resins, polyethers, phenolic resins, silicone resins, polyurea resins, amino resins, epoxy resins, polyethyleneimines, polyallylamines, and polyimides.

[0184] Commercial polymer dispersants can also be used, such as the DISPERBYK series and BYK series from BYK, the Efka series from BASF, the Solspers series from Lubrizol, the Azisper PB series from Ajinomoto Fine Techno Co., Ltd., the TEGO series from Evonik, and the Disparon series from Kusumoto Chemical Co., Ltd.

[0185] Specific examples of the above commercially available products include BYK's DISPERBYK-130, DISPERBYK-161, DISPERBYK-162, DISPERBYK-163, DISPERBYK-164, DISPERBYK-166, DISPERBYK-167, DISPERBYK-168, DISPERBYK-170, DISPERBYK-171, DISPERBYK-174, DISPERBYK-180, DISPERBYK-182, DISPERBYK-183, and DISPERBYK-1 84, DISPERBYK-185, DISPERBYK-2000, DISPERBYK-2001, DISPERBYK-2008, DISPERBYK-2009, DISPERBYK-2020, DISPERBYK-2022, DISPER BYK-2025, DISPERBYK-2050, DISPERBYK-2070, DISPERBYK-2096, DISPERBYK-2150, DISPERBYK-2155, DISPERBYK-2163, DISPERBYK-2164; BASF models EFKA4010, EFKA4015, EFKA4046, EFKA4047, EFKA4061, EFKA4080, EFKA4300, EFKA4310, EFKA4320, EFKA4330, EFKA4340, EFKA4560, EFKA4585, EFKA5207, EFKA1501, EFKA1502, EFKA1503, and EFKA PX-4701; Lubrizol's Solspers 3000, Solspers 9000, Solspers 13240, Solspers 13650, Solspers 13940, Solspers 11200, Solspers 13940, Solspers 16000, Solspers 17000, Solspers 18000, Solspers 20000, Solspers 21000, Solspers 24000, Solspers 26000, Solspers 27000, Solspers 280 00, Solspers 32000, Solspers 32500, Solspers 32550, Solspers 32600, Solspers 33000, Solspers 34750, Solspers 35100, Solspers 35200, Solspers 36000, Solspers 37500, Solspers 38500, Solspers 39000, Solspers 41000, Solspers 54000, Solspers 71000 and Solspers 76500; Ajisper PB821, Ajisper PB822, Ajisper PB881, PN411 and PA111, manufactured by Ajinomoto Fine Techno Co., Ltd. Evonik's TEGO Dispers 650, TEGO Dispers 660C, TEGO Dispers 662C, TEGO Dispers 670, TEGO Dispers 685, TEGO Dispers 700, TEGO Dispers 710 and TEGO Dispers 760W; and Examples include Disparon AQ-320, Disparon AQ-330, Disparon AQ-340, Disparon AQ-360, and Disparon AQ-380, all manufactured by Kusumoto Kasei Co., Ltd.

[0186] When using a polymeric dispersant, there are no particular restrictions on the amount it can be added, but it is preferably 1 to 100% by mass relative to the light scattering particles, and more preferably 5 to 50% by mass.

[0187] Furthermore, the wavelength conversion film-forming composition of the present invention may optionally contain a solvent. Specific examples include aromatic or halogenated aromatic hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, and chlorobenzene; aliphatic hydrocarbons such as n-heptane, n-hexane, and cyclohexane; ether solvents such as diethyl ether, tetrahydrofuran, dioxane, and 1,2-dimethoxyethane; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and cyclopentanone; and ethyl acetate, n-hexyl acetate, ethyl lactate, γ-butyrolactone, and propylene carbonate. Ester solvents such as diisopropyl malonate; halogenated hydrocarbon solvents such as methylene chloride, dichloromethane, 1,2-dichloroethane, and chloroform; amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and 1,3-dimethyl-2-imidazolidinone; alcohol solvents such as methanol, ethanol, isopropanol, n-propanol, cyclohexanol, diacetone alcohol, and 2-benzooxyethanol; ethylene glycol monoethyl ether, etc. Examples of organic solvents include glycol ether solvents such as ethylene glycol monobutyl ether, ethylene glycol diglycidyl ether, propylene glycol monomethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monoethyl ether, diethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, triethylene glycol monobutyl ether, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, dipropylene glycol monomethyl ether, and propylene glycol monomethyl ether acetate; glycol solvents such as ethylene glycol, propylene glycol, hexylene glycol, 3-octylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol, 1,3-butanediol, 2,3-butanediol, and 1,4-butanediol; nitrile solvents such as acetonitrile; and sulfur-containing solvents such as dimethyl sulfoxide.These may be used individually or in combination of two or more types.

[0188] When a wavelength conversion film-forming composition contains a solvent, the solid content concentration of the wavelength conversion film-forming composition cannot be specified in general terms, as it varies depending on the desired thickness of the wavelength conversion film and the coating method, but it is usually 10 to 70% by mass, and preferably 10 to 60% by mass.

[0189] The upper limit of the viscosity of the above wavelength conversion film-forming composition at 25°C is 10,000 mPa·s or less, preferably 1,000 mPa·s or less. The lower limit is preferably 5 mPa·s or more, and more preferably 10 mPa·s or more, considering storage stability. In this invention, viscosity refers to the measurement value obtained using an EMS viscometer.

[0190] The wavelength conversion film-forming composition of the present invention can be prepared by mixing components (A) and (B) described above, component (C) used as needed, other additives such as surfactants, and a solvent in any order.

[0191] A wavelength conversion film can be obtained by applying the above-described wavelength conversion film-forming composition of the present invention to a substrate, for example, evaporating the solvent by heating or the like as needed, and further irradiating it with active energy rays (e.g., ultraviolet light) as needed. Coating methods include, for example, reverse roll coaters, blade coaters, slit die coaters, direct gravure coaters, offset gravure coaters, kiss coaters, natural roll coaters, air knife coaters, roll blade coaters, variable bar roll blade coaters, two-stream coaters, rod coaters, wire bar coaters, applicators, dip coaters, curtain coaters, spin coaters, knife coaters, and inkjet coatings.

[0192] Heating can be done using common heating devices such as ovens or hot plates. The heating conditions are not particularly limited as long as a film can be formed, but 60-200°C for 5 minutes to 2 hours is preferred, and 80-200°C for 15 minutes to 1 hour is more preferred. The film may also be cured in stages.

[0193] While there are no particular restrictions on the irradiation of ultraviolet light as long as a film can be formed, light sources such as mercury lamps, metal halide lamps, xenon lamps, and LEDs can be used, and if necessary, a bandpass filter can be used to remove light other than the desired exposure wavelength. The wavelength of the irradiated light is preferably 200 to 440 nm, and particularly preferably includes light with a wavelength of 300 to 400 nm. The exposure dose is 10 to 4,000 mJ / cm². 2 It is preferable.

[0194] The aforementioned heating step and ultraviolet light exposure step may be combined in any order. For example, heating may be performed first and then ultraviolet light irradiation may be performed, or ultraviolet light irradiation may be performed first and then heating may be performed, or heating may be performed first, then ultraviolet light irradiation may be performed, and then further heating may be performed.

[0195] The thickness of the wavelength conversion film is not particularly limited, but is usually 1 to 1,000 μm, preferably 3 to 500 μm, and more preferably 5 to 100 μm. The haze of the wavelength conversion film is not particularly limited, but from the viewpoint of increasing the amount of light that the phosphor can absorb by scattering incident light within the film, it is preferably 18% or more, more preferably 30% or more, and more preferably 40% or more. The upper limit of the haze value is not particularly limited, but is usually around 95%. In this invention, the haze value is measured according to ASTM D1003-61. In this invention, the measurement conditions for the above haze value include, for example, the conditions for measuring a 10 μm thick film formed from a composition containing 6.7% by mass of titanium dioxide particles.

[0196] The above-mentioned substrate can be appropriately selected from those used as base materials for forming this type of film, but glass substrates or polymer plates with a light transmittance of 50% or more in the visible region of 400 to 800 nm are preferred. Specific examples of glass include soda-lime glass, barium-strontium glass, lead glass, aluminosilicate glass, borosilicate glass, barium-borosilicate glass, and quartz. Specific examples of polymers include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone.

[0197] In the present invention, when a coating film is formed using a composition (negative-type photosensitive resin composition) containing an alkali-soluble resin, a polymerizable monomer, and a photopolymerization initiator, a mask having a predetermined pattern is placed on the obtained coating film and irradiated with light such as ultraviolet light. By developing with an alkaline developer, the unexposed areas are washed out, and the remaining patterned film is heated at 80 to 140°C for 0.5 to 10 minutes as needed to obtain a sharp relief pattern on the edge surface.

[0198] Examples of the above-mentioned alkaline developers include aqueous solutions of alkali metal hydroxides such as potassium carbonate, sodium carbonate, potassium hydroxide, and sodium hydroxide; aqueous solutions of quaternary ammonium hydroxides such as tetramethylammonium hydroxide, tetraethylammonium hydroxide, and choline; and alkaline aqueous solutions of amines such as ethanolamine, propylamine, and ethylenediamine. Furthermore, surfactants known for use in developers may be added to these developers.

[0199] Among the above, a 0.1-2.58% by mass aqueous solution of tetraethylammonium hydroxide is commonly used as a developer for photoresists, and in the composition of the present invention, this alkaline developer can be used to develop the material well without causing problems such as swelling.

[0200] Furthermore, any of the following development methods can be used: the liquid-filling method, the dipping method, or the agitation immersion method. The development time in these cases is usually 15 to 180 seconds.

[0201] After development, the photosensitive resin film is washed with running water, and then air-dried using compressed air or compressed nitrogen, or by spinning, to remove moisture from the substrate and obtain a patterned film. In the above procedure, the washing time is usually about 20 to 120 seconds.

[0202] Next, by performing a post-bake on the obtained pattern-forming film for thermal curing, a film with excellent heat resistance, transparency, planarity, low water absorption, chemical resistance, etc., and a good relief pattern can be obtained. A hot plate, oven, etc., can be used to heat the above pattern-forming film.

[0203] Post-baking methods generally involve heating at a temperature selected from the range of 140 to 270°C for 5 to 30 minutes on a hot plate, or for 30 to 90 minutes in an oven. By post-baking under these conditions, a cured film with a good pattern shape can be obtained.

[0204] The wavelength conversion film obtained using the composition of the present invention has excellent wavelength conversion efficiency and durability, and is therefore suitable for use as a wavelength conversion film (color conversion film) for displays such as micro-LED displays, organic EL displays, and liquid crystal displays, as well as for lighting. [Examples]

[0205] The present invention will be described in more detail below with reference to synthesis examples, preparation examples, examples, and comparative examples, but the present invention is not limited to the following examples.

[0206] The molecular weight of the polymer was measured using a GPC system manufactured by JASCO Corporation, with Shodex® KF-804L and 803L columns, under the following conditions. Column oven: 40℃ Flow rate: 1mL / min Eluent: Tetrahydrofuran

[0207] The abbreviations used in the following examples are as follows: MMA: Methyl methacrylate • MAA: Methacrylic acid AIBN: α,α'-azobisisobutyronitrile • CPN: Cyclopentanone A11: 3-(2-benzothiazolyl)-7-(diethylamino)coumarin (coumarin 6, manufactured by Tokyo Chemical Industry Co., Ltd.) A12: Compound represented by the following formula (X1) [ka] • B2: HDDA (1,6-Hexanediol diacrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.) • B3: NDDA (1,9-nonanediol diacrylate, manufactured by Osaka Organic Chemical Industry Co., Ltd.) • B4: Irgacure OXE02 (manufactured by BASF) B5: KAYARAD DPHA (Dipentaerythritol polyacrylate, manufactured by Nippon Kayaku Co., Ltd., polymerizable monomer) • C1: Titanium dioxide particles PT-401L (rutile type, average particle size 130nm, manufactured by Ishihara Sangyo Co., Ltd.) • D1: Megafuck (registered trademark) R-40 (manufactured by DIC Corporation) • D2: Futtergent DFX-18 (manufactured by Neos Co., Ltd.) • D3: DISPARLON AQ-330 (manufactured by Kusumoto Kasei Co., Ltd.) • D4: DISPARLON AQ-320 (manufactured by Kusumoto Kasei Co., Ltd.)

[0208] <Analysis method> 1¹H-NMR spectra were measured using a nuclear magnetic resonance spectrometer, AVANCE III HD (Bruker). Chemical shift values ​​are expressed in ppm, and deuterated tetrahydrofuran and deuterated chloroform were used as solvents. 1 In the 1H-NMR spectra, the signal derived from residual protons in the solvent was used, and tetrahydrofuran was set as an internal standard at δ 1.77, 3.62 ppm, or chloroform at δ 7.26 ppm. Benzo[b]benzo[4,5]thieno[2,3-d]thiophene was purchased from BLD Pharmatech. Bromine, iodine, tris(dibenzylideneacetone)dipalladium(0)(Pd2(dba)3), diphenylamine (Ph2NH), sodium tert-butoxide (t-BuONa), and metachloroperbenzoic acid (m-CPBA) were purchased from Tokyo Chemical Industry Co., Ltd. Dichloromethane, methanol, tetrahydrofuran, o-xylene, chloroform, hexane, ethyl acetate, sodium thiosulfate, anhydrous sodium sulfate, and sodium bicarbonate were purchased from Junsei Chemical Co., Ltd. Tri-tert-butylphosphonium tetrafluoroborate (tert-Bu3PHBF4) was purchased from Fujifilm Wako Pure Chemical Industries, Ltd. Thin-layer chromatography (TLC) was performed using glass plates coated with 0.25 mm of silica gel 60F-254 (Merck). Silica gel column chromatography was performed using silica gel 60N spherical neutral (Kanto Chemical Co., Ltd.) as the packing material.

[0209] [1] Preparation of polymer solution [Synthesis Example 1] Synthesis of Acrylic Polymer B1 A solution containing acrylic polymer B1 (solid content 30% by mass) was obtained by dissolving 80.0 g of MMA, 20.0 g of MAA, and 2.5 g of AIBN in 190.0 g of CPN and reacting at 90°C for 20 hours. The resulting acrylic polymer had a manganese content of 9,900 and a manganese content of 17,300.

[0210] [2] Synthesis of fluorescent dyes [Synthesis Example 2] 2,7-Dibromobenzo[b]benzo[4,5]thieno[2,3-d]thiophene (Compound 2) [ka]

[0211] A bromo group was introduced into compound 1 using bromine to obtain compound 2 in 28% yield. Specifically, the synthesis was carried out as follows.

[0212] Bromine (14.2 g, 89.0 mmol) was dissolved in dichloromethane (500 mL) and cooled to 0°C. Benzo[b]benzo[4,5]thieno[2,3-d]thiophene (compound 1; 10.0 g, 41.6 mmol) and iodine (211 mg, 0.832 mmol), dissolved in dichloromethane (1,000 mL), were added dropwise over 1 hour. The mixture was stirred at room temperature for 62 hours. 1,000 mL of methanol was added, and the precipitated white solid was collected by suction filtration. It was washed with saturated sodium thiosulfate aqueous solution (100 mL), water (500 mL), and methanol (500 mL), and dried under reduced pressure at 50°C for 5 hours to obtain 15.0 g of white solid. Tetrahydrofuran (1,500 mL) was added to the obtained white solid (15.0 g) and the mixture was stirred at room temperature for 15 hours. The white solid in tetrahydrofuran was recovered by suction filtration and dried under reduced pressure at 50°C for 5 hours to obtain compound 2 as a white solid in a yield of 28% (4.68 g, 11.8 mmol). 1 H-NMR(500MHz,Tetrahydrofuran-d8):δ 8.29(d,J HH =2.0Hz,2H),7.92(d,J HH =8.5Hz,2H),7.67(dd,J HH (=8.5Hz, 2.0Hz, 2H).

[0213] [Synthesis example 3]N 2 ,N 2 ,N 7 ,N 7 -Tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3) [ka]

[0214] Compound 3 was obtained in 26% yield by introducing a diphenylamino group to compound 2 using a Buchwald-Hartwig coupling reaction. Specifically, the synthesis was carried out as follows.

[0215] Under an N2 gas atmosphere, 2,7-dibromobenzo[b]benzo[4,5]thieno[2,3-d]thiophene (compound 2; 4.68 g, 11.8 mmol), tris(dibenzylideneacetone)dipalladium(0) (Pd2(dba)3; 238 mg, 0.260 mmol), tri-tert-butylphosphonium tetrafluoroborate (tert-Bu3PHBF4; 281 mg, 0.968 mmol), diphenylamine (Ph2NH; 11.9 g, 70.5 mmol), and sodium tert-butoxide (t-BuONa; 7.48 g, 77.9 mmol) were dissolved in degassed o-xylene (50 mL). This was heated to 140°C and stirred for 15 hours. After adding cold water, the mixture was extracted three times with ethyl acetate. Anhydrous sodium sulfate was added to the combined organic layers to dehydrate them, and the filtrate was concentrated under reduced pressure. Concentrate (eluent: hexane; R f Compound 3 (=0.1) was purified by silica gel column chromatography (hexane → hexane / chloroform = 5 / 1 → hexane / chloroform = 2 / 1 → hexane / chloroform = 1 / 1 → chloroform). Hexane (300 mL) was added to the purified product, and the precipitated pale green solid was collected by suction filtration to obtain compound 3 as a pale green solid in 26% yield (1.75 g, 3.04 mmol). 1 H-NMR(500MHz,CDCl3):δ 7.66(d,J HH =8.5Hz,2H),7.55(d,J HH =2.0Hz,2H),7.30-7.26(m,8H),7.19(dd,J HH =8.5Hz,2.0Hz,2H),7.15-7.13(m,8H),7.06-7.03(m,4H).

[0216] [Synthesis Example 4] 2,7-Bis(diphenylamino)benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide (compound 4) (A1) [ka]

[0217] Compound 4 was obtained in 33% yield by oxidation of compound 3 with m-CPBA. Specifically, the synthesis was carried out as follows.

[0218] N 2 ,N 2 ,N 7 ,N 7 -Tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3; 1.75 g, 3.04 mmol) was dissolved in chloroform (175 mL). Metachloroperbenzoic acid (m-CPBA (30% by mass, hydrated); 1.65 g, 6.70 mmol) was slowly added at 0°C. The mixture was allowed to return to room temperature and stirred for 5 hours. Saturated sodium bicarbonate was added, and the mixture was extracted three times with chloroform. Anhydrous sodium sulfate was added to the combined organic layers to dehydrate them, and the filtrate was concentrated under reduced pressure. Concentrate (developing solvent: hexane / ethyl acetate = 3 / 1; R f Compound 4(A1) was purified by silica gel column chromatography (hexane → hexane / chloroform = 1 / 1 → hexane / chloroform = 1 / 2 → chloroform) and obtained as an orange solid in a yield of 33% (607 mg, 1.00 mmol). 1 H-NMR(500MHz,CDCl8):δ 7.78(d,J HH =8.5Hz,1H),7.44(d,J HH =2.0Hz,1H),7.36-7.28(m,9H),7.24(dd,J HH =8.5Hz,2.0Hz,1H),7.20-7.07(m,14H).

[0219] [Synthesis Example 5] 4,4'-(benzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diyl)bis(N,N-diphenylaniline) (Compound 5) [ka]

[0220] Compound 5 was obtained in 43% yield by introducing a diphenylaminophenyl group to compound 2 using a coupling reaction. Specifically, the synthesis was carried out as follows.

[0221] Under an N2 gas atmosphere, 2,7-dibromobenzo[b]benzo[4,5]thieno[2,3-d]thiophene (compound 2; 100 mg, 0.251 mmol), tetrakis(triphenylphosphine)palladium(0) (Pd(PPh3)4; 14.5 mg, 0.126 mmol), 4-(diphenylamino)phenylboronic acid (218 mg, 0.754 mmol), and sodium carbonate (133 mg, 1.26 mmol) were dissolved in a mixed solvent of 1,4-dioxane (5 mL) and water (1 mL). This mixture was heated to 90°C and stirred for 18 hours. After adding cold water, the mixture was extracted three times with ethyl acetate. Anhydrous sodium sulfate was added to the combined organic layers to dehydrate them, and the filtrate was concentrated under reduced pressure. The concentrate (developing solvent: hexane / chloroform = 1 / 1; R f Compound 5 was purified by silica gel column chromatography (hexane / chloroform = 10 / 1 → hexane / chloroform = 3 / 1 → hexane / chloroform = 1 / 1) and obtained as a yellow solid in 43% yield (78.0 mg, 0.107 mmol). 1 H-NMR (500MHz, CDCl3): δ 8.10(s,2H),7.91(d,J HH =8.5Hz,2H),7.68(dd,J HH =8.5Hz,1.5Hz,2H),7.58-7.56(m,4H),7.30-7.27(m,8H),7.19-7.15(m,12H),7.07-7.04(m,4H).

[0222] [Synthesis Example 6] 2,7-bis[4-(diphenylamino)phenyl]benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide (compound 6) (A2) [ka]

[0223] N 2 ,N 2 ,N 7 ,N 7 Compound 6(A2) was obtained as an orange solid in 14% yield (11.0 mg, 0.0145 mmol) by a reaction substantially similar to that in Synthesis Example 4, except that 4,4'-(benzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diyl)bis(N,N-diphenylaniline) (compound 5) was used instead of -tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3). 1 H-NMR(500MHz,CDCl3):δ 8.07-8.05(m,2H),7.97(d,J HH =1.5Hz,1H),7.78-7.74(m,2H),7.54-7.49(m,5H),7.32-7.27(m,8H),7.17-7.14(m,12H),7.10-7.05(m,4H).

[0224] [Synthesis Example 7] 2,7-Bis(diphenylamino)benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5,10,10-tetraoxide (Compound 7) (A3) [ka]

[0225] Compound 7(A3) was obtained in 7.2% yield by oxidizing compound 3, obtained in synthesis example 2, with m-CPBA. Specifically, the synthesis was carried out as follows.

[0226] N 2 ,N 2 ,N 7 ,N 7-Tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3; 100 mg, 0.174 mmol) was dissolved in 1,2-dichloroethane (10 mL). Metachloroperbenzoic acid (m-CPBA (30% by mass, hydrated); 450 mg, 1.83 mmol) was added. The mixture was heated to 70°C and stirred for 29 hours. Saturated sodium bicarbonate aqueous solution was added, and the mixture was extracted three times with chloroform. Anhydrous sodium sulfate was added to the combined organic layers to dehydrate them, and the filtrate was concentrated under reduced pressure. Concentrate (developing solvent: hexane / ethyl acetate = 2 / 1; R f Compound 7(A3) was purified by silica gel column chromatography (hexane / chloroform = 1 / 1 → chloroform) and obtained as a red solid in a yield of 7.2% (8.00 mg, 0.00125 mmol). 1 H-NMR (500MHz, CDCl3): δ 7.38-7.33(m,12H),7.22-7.19(m,4H),7.16(d,J HH =7.5Hz,8H),7.10(dd,J HH (=8.5Hz, 2.0Hz, 2H).

[0227] [Synthesis example 8]N 2 ,N 7 -di(naphthalene-1-yl)-N 2 ,N 7 -Diphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 8) [ka]

[0228] Compound 8 was obtained in 87% yield by introducing an N-phenyl-1-naphthylamino group to compound 2, obtained in synthesis example 2, using a Buchwald-Hartwig coupling reaction. Specifically, the synthesis was carried out as follows.

[0229] Under an N2 gas atmosphere, 2,7-dibromobenzo[b]benzo[4,5]thieno[2,3-d]thiophene (compound 2; 500 mg, 1.26 mmol), tris(dibenzylideneacetone)dipalladium(0) (Pd2(dba)3; 25.4 mg, 0.0280 mmol), tri-tert-butylphosphonium tetrafluoroborate (tert-Bu3PHBF4; 30.0 mg, 0.103 mmol), N-phenyl-1-naphthylamine (605 mg, 2.76 mmol), and sodium tert-butoxide (t-BuONa; 400 mg, 4.16 mmol) were dissolved in degassed o-xylene (5 mL). This mixture was heated to 140°C and stirred for 6 hours. Add water (5 mL) and stir for 1 hour. The precipitated brown solid is collected by suction filtration, washed with water (5 mL) and hexane (5 mL), and compound 8 (developing solvent: hexane; R f The solution (=0.1) was obtained as a brown solid in 87% yield (736 mg, 1.09 mmol). 1 H-NMR(500MHz,CDCl3):δ 7.96(d,J HH =8.5Hz,2H),7.90(d,J HH =8.5Hz,2H),7.79(d,J HH =8.5Hz,2H),,7.58(d,J HH =8.5Hz,2H),7.50-7.44(m,6H),7.37-7.34(m,4H),7.24-7.20(m,4H),7.16(dd,J HH =8.5Hz,2.0Hz,2H),7.07(d,J HH =7.5Hz, 4H), 6.98-6.95(m, 2H).

[0230] [Synthesis Example 9] 2,7-Bis(naphthalene-1-yl(phenyl)amino)benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide (compound 9) (A4) [ka]

[0231] N 2 ,N 2 ,N7 ,N 7 -N is used instead of tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3). 2 ,N 7 -di(naphthalene-1-yl)-N 2 ,N 7 Compound 9 (A4) was obtained as an orange solid in a yield of 8.8% (18.4 mg, 0.0260 mmol) by a reaction substantially similar to that in Synthesis Example 4, except for the use of -diphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 8). 1 H-NMR (500MHz, CDCl3): δ 7.92-7.80(m,6H),7.73(d,J HH =9.0Hz,1H),7.53-7.46(m,4H),7.44-7.40(m,1H),7.38-7.33(m,3H),7.31-7. 28(m,4H),7.24-7.18(m,5H),7.12-7.09(m,4H),7.03-7.00(m,1H),6.87(dd,J HH (=8.5Hz, 2.0Hz, 1H).

[0232] [Synthesis Example 10] 2,7-di(9H-carbazole-9-yl)benzo[b]benzo[4,5]thieno[2,3-d]thiophene (compound 10) [ka]

[0233] Compound 10 was obtained as a brown solid in 81% yield (580 mg, 1.02 mmol) using a reaction substantially similar to that in Synthesis Example 8, except that carbazole was used instead of N-phenyl-1-naphthylamine. 1 H-NMR(500MHz,CDCl3):δ 8.20-8.14(m,8H),7.72(dd,J HH =8.0Hz,1.5Hz,2H),7.51-7.44(m,8H),7.35-7.32(m,4H).

[0234] [Synthesis Example 11] 2,7-di(9H-carbazole-9-yl)benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide (compound 11) (A5) [ka]

[0235] N 2 ,N 2 ,N 7 ,N 7 Compound 11(A5) was obtained as an orange solid in 56% yield (119 mg, 0.197 mmol) by a reaction substantially similar to that in Synthesis Example 4, except that 2,7-di(9H-carbazole-9-yl)benzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3) was replaced with 2,7-di(9H-carbazole-9-yl)benzo[b]benzo[4,5]thieno[2,3-d]thiophene (compound 10). 1 H-NMR(500MHz,CDCl3):δ 8.30(d,J HH =8.5Hz,1H),8.19-8.16(m,5H),8.09(d,J HH =2.0Hz,1H),7.89(dd,J HH =8.5Hz,2.0Hz,1H),7.83-7.80(m,2H),7.53-7.46(m,8H),7.38-7.33(m,4H).

[0236] [Synthesis example 12]N 2 ,N 2 ,N 7 ,N 7 -Tetrakis[4-(tert-butyl)phenyl]benzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 12) [ka]

[0237] Compound 12 was obtained as a yellowish-green solid in 81% yield (487 mg, 0.609 mmol) by a reaction substantially similar to that in Synthesis Example 8, except that bis(4-tert-butylphenyl)amine was used instead of N-phenyl-1-naphthylamine. 1 H-NMR(500MHz,Tetrahydrofuran-d8):δ 7.70-7.69(m,2H),7.60(s,2H),7.34(d,J HH =7.5Hz,8H),7.20-7.17(m,2H),7.07(d,J HH =7.5Hz, 8H), 1.35(S, 36H).

[0238] [Synthesis Example 13] 2,7-Bis{bis[4-(tert-butyl)phenyl]amino}benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide (Compound 13) (A6) [ka]

[0239] N 2 ,N 2 ,N 7 ,N 7 -N is used instead of tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3). 2 ,N 2 ,N 7 ,N 7 Compound 13 (A6) was obtained as an orange solid in a yield of 5.9% (6.10 mg, 0.00734 mmol) by a reaction substantially similar to that in Synthesis Example 4, except for the use of -tetrakis[4-(tert-butyl)phenyl]benzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 12). 1 H-NMR(500MHz,CDCl3):δ 7.74(d,J HH =8.5Hz,1H),7.40(s,1H),7.36-7.28(m,9H),7.22-7.20(m,1H),7.14(d,J HH=8.5Hz,1H),7.09-7.03(m,9H),1.33-1.32(m,36H).

[0240] [Synthesis example 14]N 2 ,N 2 ,N 7 ,N 7 -Tetra-metha-tolylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 14) [ka]

[0241] Compound 14 was obtained as a yellow solid in 50% yield (236 mg, 0.374 mmol) using a reaction substantially similar to that in Synthesis Example 8, except that di-methatolylamine was used instead of N-phenyl-1-naphthylamine. 1 H-NMR(500MHz,CDCl3):δ 7.64(d,J HH =8.5Hz,2H),7.50(s,2H),7.18-7.15(m,6H),6.95-6.92(m,8H),6.86(d,J HH =7.5Hz, 4H), 2.27(s, 12H).

[0242] [Synthesis Example 15] 2,7-Bis(di-meth-tolylamino)benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide (Compound 15) (A7) [ka]

[0243] N 2 ,N 2 ,N 7 ,N 7 -N is used instead of tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3). 2 ,N 2 ,N 7 ,N 7Compound 15 (A7) was obtained as an orange solid in 23% yield (56.2 mg, 0.0848 mmol) by a reaction substantially similar to that in Synthesis Example 4, except for the use of -tetra-metha-tolylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 14). 1 H-NMR(500MHz,CDCl3):δ 7.77(d,J HH =8.5Hz,1H),7.39(s,1H),7.30(s,1H),7.24-7.17(m,7H),7.07-7.05(m,1H),6.99-6.89(m,11H),2.30-2.28(m,12H).

[0244] [Synthesis example 16]N 2 ,N 2 ,N 7 ,N 7 -Tetra-para-tolylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 16) [ka]

[0245] Compound 16 was obtained as a yellow solid in 69% yield (326 mg, 0.517 mmol) using a reaction substantially similar to that in Synthesis Example 8, except that di-para-tolylamine was used instead of N-phenyl-1-naphthylamine. 1 H-NMR(500MHz,CDCl3):δ 7.60(d,J HH =6.5Hz,2H),7.47(s,2H),7.15-7.02(m,18H),2.33(s,12H).

[0246] [Synthesis Example 17] 2,7-Bis(di-para-tolylamino)benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide (compound 17) (A8) [ka]

[0247] N2 ,N 2 ,N 7 ,N 7 -N is used instead of tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3). 2 ,N 2 ,N 7 ,N 7 Compound 17 (A8) was obtained as an orange solid in 37% yield (127 mg, 0.192 mmol) by a reaction substantially similar to that in Synthesis Example 4, except for the use of -tetra-para-tolylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 16). 1 H-NMR(500MHz,CDCl3):δ 7.73(d,J HH =8.5Hz,1H),7.35(s,1H),7.27(s,1H),7.18-7.09(m,10H),7.05-7.00(m,9H),2.35-2.33(m,12H).

[0248] [Synthesis example 18]N 2 ,N 2 ,N 7 ,N 7 -Tetra-ortho-tolylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 18) [ka]

[0249] Compound 18 was obtained as a yellow solid in 25% yield (120 mg, 0.190 mmol) using a reaction substantially similar to that in Synthesis Example 8, except that di-ortho-tolylamine was used instead of N-phenyl-1-naphthylamine. 1 H-NMR(500MHz,CDCl3):δ 7.55(d,J HH =9.0Hz,2H),7.22(d,J HH =7.5Hz,4H),7.18-7.10(m,12H),7.00-6.98(m,2H),6.83(d,J HH =8.5Hz, 2H), 2.04(s, 12H).

[0250] [Synthesis Example 19] 2,7-Bis(di-ortho-tolylamino)benzo[b]benzo[4,5]thieno[2,3-d]thiophene 5,5-dioxide (compound 19) (A9) [ka]

[0251] N 2 ,N 2 ,N 7 ,N 7 -N is used instead of tetraphenylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 3). 2 ,N 2 ,N 7 ,N 7 Compound 19 (A9) was obtained as an orange solid in 37% yield (23.0 mg, 0.0347 mmol) by a reaction substantially similar to that in Synthesis Example 4, except for the use of -tetra-ortho-tolylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene-2,7-diamine (compound 18). 1 H-NMR(500MHz,CDCl3):δ 7.70(d,J HH =8.5Hz,1H),7.26-7.23(m,3H),7.20-7.11(m,10H),7.04-6.96(m,6H),6.86(d,J HH =8.5Hz,1H),6.65(d,J HH =9.0Hz, 1H), 2.10-2.03(m, 12H).

[0252] [Synthesis Example 20] Fluorescent dye compound A10 The fluorescent dye compound A10, represented by the following formula, was obtained according to the synthesis method described in ACS Materials Lett. 2021, 3, 42-49. [ka]

[0253] [3] Preparation of light scattering particle dispersion [Preparation Example 1] Preparation of Light Scattering Particle Dispersion 1 Acrylic polymer solution B1 was added to a 50 ml glass vial in an amount of 50% by mass relative to light-scattering particles C1 in terms of solid content ratio. CPN was then added to adjust the solid content concentration to 30% by mass. Subsequently, 1 mm diameter zirconia balls were added to the container and ball milling was performed by stirring for 48 hours using a VMR-5R mix rotor manufactured by AS ONE Corporation to obtain light-scattering particle dispersion 1. The particle size distribution of the obtained dispersion was measured using Nanotrac UPA (manufactured by Microtrac). The solvent of the dispersion was used as the diluent, and the 50% cumulative diameter (D50) of the particles in the dispersion was calculated on a volume basis using MicrotracDMS analysis software manufactured by Nikkiso Co., Ltd. from the scattering generated when the diluted sample was irradiated with laser light, and it was found to be 181 nm.

[0254] [Preparation Example 2] Preparation of Light Scattering Particle Dispersion 2 A slurry was obtained by adding 143.3g of B3 and 80.0g of C1 to a 500ml polystyrene bottle, then adding 26.7g of D3 diluted to 30% with B3 under dispersive stirring, and stirring at 1,000 rpm for 30 minutes. The amount of D3 added relative to C1 was 10% by mass. Next, after transferring the entire slurry to a slurry tank, a light-scattering particle dispersion 2 was obtained by performing a 5-pass process using a LabMinister DMS65 bead mill manufactured by Ashizawa Finetech Co., Ltd., with 0.2 mm diameter zirconia beads filling the tank at 60% by volume, under conditions of a liquid delivery speed of 40 ml / min and a disk peripheral speed of 8 m / s. The particle size distribution of the obtained dispersion was measured using Nanotrac UPA (manufactured by Microtrac). B3 was used as the diluent, and the 50% cumulative diameter (D50) of the particles in the dispersion was calculated on a volume basis using MicrotracDMS analysis software manufactured by Nikkiso Co., Ltd. from the scattering generated when the diluted sample was irradiated with laser light, and it was found to be 134 nm.

[0255] [Preparation Example 3] Preparation of Light Scattering Particle Dispersion 3 A slurry was obtained by adding particle dispersant D4 in an amount of 20% by mass relative to light scattering particles C1 in a 500 ml polystyrene bottle, and then adding CPN to adjust the solid content concentration to 30% by mass. The mixture was then dispersed and stirred at 1,000 rpm for 30 minutes. Next, the entire slurry was transferred to a slurry tank, and a light scattering particle dispersion 3 was obtained by performing 10 passes using a bead mill device LabMinister DMS65 manufactured by Ashizawa Finetech Co., Ltd., with 60% by volume of 0.2 mm diameter zirconia beads packed inside, at a liquid delivery rate of 60 ml / min and a disk peripheral speed of 8 m / s. The particle size distribution of the obtained dispersion was measured using Nanotrac UPA (manufactured by Microtrac). CPN was used as the diluent, and the 50% cumulative diameter (D50) of particles in the dispersion was calculated on a volume basis using MicrotracDMS analysis software manufactured by Nikkiso Co., Ltd. from the scattering generated when the diluted sample was irradiated with laser light. The result was 185 nm, and the volume-average particle diameter was 191 nm.

[0256] [4] Preparation and evaluation of compositions for wavelength conversion film formation. [Examples 1-9, Comparative Example 1] Preparation and evaluation of compositions for wavelength conversion film formation. (1) Preparation of compositions for forming wavelength conversion films A composition for forming a wavelength-converting film was prepared by mixing each component according to the composition shown in Table 1 and filtering the resulting mixture using a PTFE filter with a pore size of 0.2 μm. Note that the composition ratios in Table 1 represent the ratios based on solid content.

[0257] [Table 1]

[0258] (2) Evaluation 1: Evaluation of lightfastness The wavelength conversion film-forming compositions of Examples 1-9 and Comparative Example 1 were applied to quartz substrates using a spin coater. Pre-baking was then performed on a hot plate at 100°C for 120 seconds, followed by post-baking at 160°C for 30 minutes to obtain three substrates with a film thickness of 1 μm. These were referred to as substrates A, B, and C. Next, substrate A was subjected to a nitrogen atmosphere, and substrate B to air under a blue LED light (manufactured by CCS Corporation, emission peak wavelength 450 nm, illuminance 2.1 mW / cm²). 2 The substrates were placed on top of each other, and LED lights were turned on for 20 hours of light irradiation. During this time, substrate C was stored in the air in a light-shielded state. Subsequently, a fluorescence spectrometer (Hitachi, Ltd. F-7000) was used to measure the fluorescence spectra of all substrates excited at a predetermined excitation wavelength. The fluorescence intensity retention rate under nitrogen atmosphere was defined as the value obtained by dividing the peak intensity of the fluorescence spectrum of substrate A by the peak intensity of the fluorescence spectrum of substrate C, and the fluorescence intensity retention rate under air was defined as the value obtained by dividing the peak intensity of the fluorescence spectrum of substrate B by the peak intensity of the fluorescence spectrum of substrate C. The evaluation results are shown in Table 2.

[0259] [Table 2]

[0260] As shown in Table 2, Examples 1 to 9, which satisfy the requirements of the present invention, showed superior lightfastness, with a higher retention rate of fluorescence intensity after light irradiation in a nitrogen atmosphere, compared to Comparative Example 1, which used a dye that did not satisfy the requirements of the present invention. Furthermore, Examples 1 to 3 and 5 to 9 showed superior lightfastness, with a higher retention rate of fluorescence intensity after light irradiation even in air, compared to Comparative Example 1.

[0261] [Examples 10-15, Comparative Examples 2-10] (1) Preparation of compositions for forming wavelength conversion films The components were mixed according to the compositions shown in Tables 3 and 4. The resulting mixture was filtered using a polytetrafluoroethylene (PTFE) filter with a pore size of 5.0 μm to prepare a composition for wavelength conversion film formation. The composition ratios in Tables 3 and 4 represent the mass ratio of solid content.

[0262] [Table 3]

[0263] [Table 4]

[0264] (2) Evaluation of film properties The resin compositions of Examples 10-12 and Comparative Examples 2-6 were applied to a quartz substrate using a spin coater, followed by pre-baking on a hot plate at 100°C for 120 seconds, and then post-baking at 160°C for 30 minutes to obtain coated film samples with a thickness of 10 μm. Furthermore, after coating each composition of Example 13 and Comparative Example 7 using a spin coater, exposure was performed at 2000 mJ / cm using a UV-LED exposure system (emission peak wavelength 365 nm) manufactured by CCS Corporation. 2 A coating sample with a thickness of 10 μm was obtained by irradiating it with ultraviolet light and then performing a post-bake at 160°C for 30 minutes. Furthermore, the resin compositions of Examples 14, 15 and Comparative Examples 8-10 were applied to a quartz substrate using a spin coater, and then pre-baked on a hot plate at a temperature of 100°C for 120 seconds. This coating was then exposed to light at 365 nm with a Canon PLA-600FA ultraviolet irradiation device at a light intensity of 3 mW / cm². 2 UV radiation at 500 mJ / cm² 2 The sample was irradiated with the specified exposure dose. Subsequently, a post-bake was performed at 160°C for 30 minutes to obtain a coating sample with a thickness of 10 μm.

[0265] For the obtained coating samples, the haze value was measured using a turbidimeter NDH5000 manufactured by Nippon Denshoku Industries Ltd., in accordance with the measurement method of ASTM D 1003-61. Next, the coating samples were placed on a blue LED light (emission peak wavelength 450 nm) manufactured by CCS Corporation, and the LED light was turned on. The light emitted through the coating samples was measured using a spectroradiometer USR-45 manufactured by Ushio Inc., and this was recorded as Result (I). Similarly, the light emitted from only the LED light, excluding the coating samples, was measured in the same manner and this was recorded as Result (II). From the obtained spectral irradiance spectra, the number of photons of light with wavelengths of 480 nm or less in Result (II) was defined as the "excited photon count". Similarly, the number of photons of light with wavelengths of 480 nm or less in Result (I) was defined as the "transmitted photon count". Similarly, the number of photons of light with wavelengths of 480 nm or more in Result (I) was defined as the "emitted photon count". The "blue light absorption rate" and "conversion efficiency" were calculated using the following formulas. Blue light absorption rate = (Number of excited photons - Number of transmitted photons) ÷ Number of excited photons Conversion efficiency = Number of emitted photons ÷ Number of excited photons

[0266] (3) Evaluation of lightfastness Three coating samples prepared under the same conditions as those used in (2) above were irradiated for 100 hours with 450 nm wavelength light using a CCS Corporation blue LED exposure system in air or under a nitrogen atmosphere in a VAC glove box. After irradiation, the blue light absorptivity and conversion efficiency were measured for the coating samples in the same manner as in Evaluation 1. The "maintenance rate" of the blue light absorptivity was calculated by dividing the blue light absorptivity after irradiation by the blue light absorptivity before irradiation, and the "maintenance rate" of the conversion efficiency was calculated by dividing the conversion efficiency after irradiation by the conversion efficiency before irradiation.

[0267] The results of the evaluations in (2) and (3) above are shown in Tables 5 and 6.

[0268] [Table 5]

[0269] [Table 6]

[0270] As shown in Tables 5 and 6, in Examples 10 to 15 using the phosphor of the present invention, the retention rate of conversion efficiency after the lightfastness test was better than in Comparative Examples 2 to 10, not only in a nitrogen atmosphere but also in air.

Claims

1. A composition for forming a wavelength conversion film, comprising a phosphor consisting of a fused thiophene compound represented by the following formula (1), and a binder (B). 【Chemistry 1】 (In the formula, Ar 1 and Ar 2 Each of these is an aromatic ring that may have substituents, R 1 ~R 4 Each of these is independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted aryl group, or an optionally substituted heteroaryl group, and R 1 ~R 4 Not all of them become hydrogen atoms at the same time. R 1 and R 2 may combine with each other to form a ring together with adjacent nitrogen atoms, and R 3 and R 4 may combine with each other to form a ring together with adjacent nitrogen atoms, and R 1 and R 2 either one or both of them may combine with Ar 1 to form a ring together with adjacent nitrogen atoms, and R 3 and R 4 either one or both of them may combine with Ar 2 to form a ring together with adjacent nitrogen atoms, Y 1 and Y 2 One side is -SO 2 - and the other is -S- or -SO 2 - That is the case.

2. The above Y 1 and Y 2 One side is -SO 2 The wavelength conversion film forming composition according to claim 1, wherein the other is - and the other is -S-.

3. The above Ar 1 and Ar 2 The wavelength conversion film-forming composition according to claim 1, wherein the aromatic ring may have substituents.

4. The above R 1 ~R 4 The wavelength conversion film-forming composition according to claim 1, wherein the aryl group may have substituents.

5. Furthermore, the wavelength conversion film forming composition according to claim 1, further comprising (C) light scattering particles.

6. The wavelength conversion film forming composition according to claim 5, wherein the above (C) light scattering particles are titanium oxide particles.

7. The wavelength conversion film forming composition according to claim 1, wherein the above (B) binder contains a resin.

8. The wavelength conversion film forming composition according to claim 1, wherein the above (B) binder comprises a polymerizable monomer and a photopolymerization initiator.

9. The wavelength conversion film forming composition according to claim 1, wherein the above (B) binder comprises an alkali-soluble resin, a polymerizable monomer, and a photopolymerization initiator.

10. The wavelength conversion film forming composition according to claim 1, wherein the content of the above-mentioned (A) phosphor is 0.1% by mass or more in the solid content.

11. The wavelength conversion film forming composition according to claim 5, wherein the content of the above (C) light scattering particles is 1% by mass or more in the solid content.

12. The wavelength conversion film forming composition according to claim 1, wherein the haze value of the film formed from the above composition is 18% or more.

13. A fused ring thiophene compound represented by the following formula (1). 【Chemistry 2】 (In the formula, Ar 1 and Ar 2 Each of these is an aromatic ring that may have substituents, R 1 ~R 4 Each of these is independently a hydrogen atom, an optionally substituted alkyl group, an optionally substituted cycloalkyl group, an optionally substituted aryl group, or an optionally substituted heteroaryl group, and R 1 ~R 4 Not all of them become hydrogen atoms at the same time. R 1 and R 2 These may bond with each other to form a ring with adjacent nitrogen atoms, R 3 and R 4 These may bond with each other to form a ring with adjacent nitrogen atoms, R 1 and R 2 Either one or both of Ar 1 It may bond with R to form a ring with adjacent nitrogen atoms, 3 and R 4 Either one or both of Ar 2 It may bond with an adjacent nitrogen atom to form a ring, Y 1 and Y 2 One side is -SO 2 - and the other is -S-.

14. The above Ar 1 and Ar 2 The fused ring thiophene compound according to claim 13, wherein the aromatic ring may have substituents.

15. The above R 1 ~R 4 The fused ring thiophene compound according to claim 13, wherein the aryl group may have a substituent.

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