JP2013030590A - Optical filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical filter and a color conversion filter which absorb light in an ultraviolet light region (250 to 400 nm).SOLUTION: Provided is a dye represented by the general formula (1). In the formula: Rto Rindependently represent a hydrogen atom, a halogen atom, a nitro group, a cyano group, an aldehyde group, a carboxyl group, a hydroxyl group, -NRR', a hydrocarbon group having 1-20 carbon atoms which may contain substituents, or a heterocyclic group having 1-20 carbon atoms which may contain substituents; Xand Xindependently represent an oxygen atom, a sulfur atom, or an NR" group; R, R' and R" independently represent a hydrogen atom, a hydrocarbon group having 1-20 carbon atoms which may contain substituents, or a heterocyclic group having 1-20 carbon atoms which may contain substituents; Z and Z' represent direct binding or a divalent linking group; and n represents 0, 1 or 2.

Description

  The present invention relates to an optical filter including a benzoazole dye having at least two azole rings (hereinafter also simply referred to as a benzoazole dye). The optical filter is an optical filter that enables high-definition, high-brightness, and high-efficiency multicolor display, and has excellent productivity. The present invention also relates to an optical filter that is a color conversion filter including the benzoazole dye and having wavelength conversion ability. The color conversion filter of the present invention is suitably used for photoelectric conversion elements such as solar cells, as well as liquid crystal, PDP, image sensors, personal computers, word processors, audio, video, car navigation, telephones, portable terminals, and industrial use. It is also useful for displays such as measuring instruments, fluorescent lamps, LEDs, illumination such as EL illumination, dye lasers, copy protection and the like.

  Compounds having absorption in the ultraviolet region are used as light absorbers in optical filters used for photoelectric conversion elements such as solar cells, liquid crystals, PDPs, OLEDs, LED displays, illumination applications, and the like.

  On the other hand, conventional materials that radiate electromagnetic waves as extra energy when electrons excited by absorbing energy return to the ground state have wavelength conversion ability due to the difference between absorption and emission energy. As a color conversion dye (wavelength conversion dye), it is used in dyes, pigments, optical filters, agricultural films, etc., and in organic compounds, the absorption and emission wavelengths are easier to control compared to inorganic compounds. Have been studied. Compounds that emit absorbed energy as fluorescence are called fluorescent dyes, and those that emit visible light fluorescence are highly practical. For example, display devices such as displays, illumination devices such as fluorescent lamps, solar cells, etc. It can be used for photoelectric conversion elements, as a marker in biology and medicine.

  An optical filter (color conversion filter) containing a color conversion dye is required to have high light resistance for its use. Moreover, when using as a use for solar cells, it is desirable to absorb a wavelength region (specifically, 250 to 340 nm) in which the power generation efficiency of the solar cell is extremely low and to convert it into a wavelength region with high power generation efficiency. In addition, a color conversion filter having a large Stoke shift can be converted into a visible region with higher power generation efficiency, and has been studied in Patent Document 1, for example. Patent Document 1 describes an optical filter (color conversion filter) containing a naphtholactam derivative represented by a specific general formula. When the optical filter is used for a solar cell, the power generation efficiency is improved as a whole solar cell. However, since the wavelength region to be absorbed is around 400 nm, there is a problem that the power generation efficiency around 400 nm is lowered. .

  Patent Documents 2 to 4 show benzoazole compounds having two azole rings. Patent Document 5 discloses a photoelectric conversion device (solar cell module) using a color conversion material.

International Publication No. 2011/010537 JP 2003-342266 A JP 2008-130599 A JP 2010-505894 A JP 2006-303033 A

  Accordingly, an object of the present invention is to provide an optical filter that absorbs light in the ultraviolet light region (250 to 400 nm), in particular, has wavelength conversion ability, absorbs light in a particularly unnecessary wavelength region in the ultraviolet light region, and is useful. It is another object of the present invention to provide a color conversion filter that converts light into longer wavelength light. A further object of the present invention is to provide a color conversion light emitting device and a photoelectric conversion device using the color conversion filter.

  As a result of intensive studies, the present inventors have found that a color conversion filter containing a benzoazole compound having at least two azole rings and having a color conversion ability that emits fluorescence absorbs a short wavelength region and has a useful wavelength. It has been found that the above object can be achieved by using the optical filter.

  The present invention (invention according to claim 1) is based on the above findings and provides an optical filter including at least one benzoazole dye having at least two azole rings.

  The present invention (the invention according to claim 2) provides the optical filter according to claim 1, wherein the benzoazole dye having at least two azole rings is a compound represented by the following general formula (1): It is.

Further, in the present invention (the invention according to claim 3), Z in the general formula (1) is substituted with a C1-C4 alkanediyl group which may be substituted with a halogen atom or a halogen atom. divalent cyclic hydrocarbon group of good 3 to 20 carbon atoms and, -O -, - S -, - SO 2 -, - SS -, - SO -, - a CO- or -OCO-, The optical filter according to claim 2, wherein n is 0.

  Moreover, this invention (invention of Claim 4) is a color conversion filter which has wavelength conversion ability, The optical filter as described in any one of Claims 1-3 is provided.

  Moreover, this invention (invention of Claim 5) provides the color conversion light-emitting device containing the light emission part and the optical filter of Claim 4.

  Moreover, this invention (invention of Claim 6) provides the photoelectric conversion device containing a photoelectric conversion element and the optical filter of Claim 4.

  According to the present invention, an optical filter that absorbs light in the ultraviolet region (250 to 400 nm) can be provided. Among the optical filters of the present invention, those having wavelength conversion ability absorb light in an unnecessary wavelength region, emit fluorescence in a preferable wavelength region, and do not reduce luminance, so that it is suitable for a color conversion light emitting device, a photoelectric conversion device, etc. Is preferred.

FIG. 1A is a cross-sectional view showing a preferred embodiment of the optical filter of the present invention. FIG. 1B is a cross-sectional view showing another preferred embodiment of the optical filter of the present invention. FIG. 1C is a cross-sectional view showing still another preferred embodiment of the optical filter of the present invention. FIG. 2A is a schematic cross-sectional view showing a preferred embodiment of a ballistic LED device which is an example of a color conversion light-emitting device using the color conversion filter of the present invention. FIG. 2B is a schematic cross-sectional view showing another preferred embodiment of a ballistic LED device which is an example of a color conversion light-emitting device using the color conversion filter of the present invention. FIG. 2C is a schematic cross-sectional view showing still another preferred embodiment of a ballistic LED device which is an example of a color conversion light-emitting device using the color conversion filter of the present invention. FIG. 2D is a cross-sectional view showing a preferred embodiment of a color conversion light-emitting device in which LED chips that are examples of a color conversion light-emitting device using the color conversion filter of the present invention are enumerated. FIG. 2E is a cross-sectional view showing another preferred embodiment of a color conversion light emitting device in which LED chips, which are examples of a color conversion light emitting device using the color conversion filter of the present invention, are enumerated. FIG. 2F is a cross-sectional view showing still another preferred embodiment of a color conversion light-emitting device in which LED chips, which are examples of a color conversion light-emitting device using the color conversion filter of the present invention, are enumerated. FIG. 3 is a schematic cross-sectional view showing an embodiment of a color conversion light-emitting device for a color display which is a preferred example of a color conversion light-emitting device using the color conversion filter of the present invention. FIG. 4 is a schematic cross-sectional view showing a preferred embodiment of a photoelectric conversion device using the color conversion filter of the present invention.

  Hereinafter, the optical filter, color conversion light-emitting device, and photoelectric conversion device of the present invention will be described in detail based on preferred embodiments.

First, the benzoazole dye used for the optical filter of the present invention will be described.
The benzoazole dye may have at least two azole rings in the molecule. If there is one azole ring, it may sublime at the time of film formation or the absorption fluorescence characteristics may not be suitable. The number of azole rings in the molecule is preferably at most four. If the number of azole rings is 5 or more, the solubility may be lowered. The benzoazole dye preferably has a molecular weight of 300 to 3000, and more preferably 500 to 1500. The azole ring is preferably an oxazole ring, and more preferably the oxazole ring is a benzoxazole ring.

  As said benzoazole pigment | dye, the compound represented by the said General formula (1) is mentioned preferably, The compound etc. which are represented with the following general formula (2) or (3) are mentioned. The compound represented by the general formula (1) is preferable in that it has excellent solubility in resins and solvents.

In the general formulas (1) to (3), examples of the halogen atom represented by R ^{1 to} R ¹² include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

In the general formulas (1) to (3), the hydrocarbon group of the hydrocarbon group having 1 to 20 carbon atoms which may be substituted represented by R ^{1 to} R ¹² , R, R ′ and R ″ Includes an aromatic hydrocarbon group, an aliphatic hydrocarbon group, an aromatic hydrocarbon group substituted with an aliphatic hydrocarbon, and the like.
Examples of the aromatic hydrocarbon group include phenyl, naphthyl, cyclohexylphenyl, biphenyl, terphenyl, fluoryl, thiophenylphenyl, furanylphenyl, 2′-phenyl-propylphenyl, benzyl, naphthylmethyl, and the like.
Examples of the aliphatic hydrocarbon group include methyl, ethyl, propyl, isopropyl, butyl, s-butyl, t-butyl, isobutyl, amyl, isoamyl, t-amyl, hexyl, heptyl, isoheptyl, t-heptyl, and n-octyl. Linear, branched and cyclic alkyl groups such as cyclooctyl, isooctyl, t-octyl, nonyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, etc. Group hydrocarbon groups include —O—, —COO—, —OCO—, —CO—, —S—, —SO—, —SO ₂ —, —NR ¹³ —, —C═C—, —C≡C. -May be interrupted with-, and R ¹³ is the same group as the hydrocarbon group,
Examples of the aromatic hydrocarbon group substituted with the aliphatic hydrocarbon group include phenyl, naphthyl, benzyl and the like substituted with the aliphatic hydrocarbon group.
Examples of the group that may substitute these hydrocarbon groups include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a hydroxyl group, a thiol group, and a —NR ¹⁴ R ¹⁵ group. ^The group represented by ¹⁴ and R ¹⁵ is the same group as the above hydrocarbon group. In addition, when the group which interrupts and / or substitutes the said hydrocarbon group contains a carbon atom, the carbon atom number including the group which interrupts and / or substitutes is 1-20.

In the above general formulas (1) to (3), the optionally substituted heterocyclic group having 1 to 20 carbon atoms represented by R ^{1 to} R ¹² , R, R ′ and R ″ may be aromatic. Examples include a heterocyclic group, an aliphatic heterocyclic group, an aromatic heterocyclic group substituted with an aliphatic hydrocarbon group, and an aliphatic heterocyclic group substituted with an aliphatic hydrocarbon group.
Examples of the aromatic heterocyclic group include furanyl, thiophenyl, chromenyl, thiochromenyl, benzofuranyl, benzothiophenyl, pyrrolyl, imidazolyl, pyrazolyl, oxazolyl, thiazolyl, benzoxazolyl, benzothiazolyl, pyridyl, pyrazinyl, pyrimidinyl, pyridazinyl, indolyl, etc. Are mentioned,
Examples of the aliphatic heterocyclic group include tetrahydrofuranyl, pyrrolidinyl, imidazolidinyl, pyrazolidinyl, piperidyl, piperazinyl, morpholinyl and the like.
Examples of the aromatic heterocyclic group substituted with the aliphatic hydrocarbon group include the aromatic heterocyclic group substituted with the aliphatic hydrocarbon group,
Examples of the aliphatic heterocyclic group substituted with the aliphatic hydrocarbon group include the aliphatic heterocyclic group substituted with the aliphatic hydrocarbon group.
Examples of the group that may substitute these heterocyclic groups include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, a cyano group, a nitro group, a hydroxyl group, a thiol group, and a —NR ¹⁴ R ¹⁵ group. ^The group represented by ¹⁴ and R ¹⁵ is the same group as the above hydrocarbon group. In addition, when the group which interrupts and / or substitutes the said hydrocarbon group contains a carbon atom, the carbon atom number including the group which interrupts and / or substitutes is 1-20.

Although it does not specifically limit as a bivalent coupling group represented by Z in the said General formula (1), C1-C4 alkanediyl group, C3-C20 bivalent cyclic carbonization Preferred examples include a hydrogen group, —O—, —S—, —SO ₂ —, —SS—, —SO—, —CO—, —OCO—, and the alkanediyl group and the divalent cyclic hydrocarbon group. May be substituted with a halogen atom. It is preferable that Z is a divalent linking group because production is easy.
Examples of the alkanediyl group having 1 to 4 carbon atoms include methane-1,1-diyl, ethane-1,2-diyl, propane-1,3-diyl, butane-1,4-diyl, and ethane-1,1. -Diyl, propane-2,2-diyl and the like.
Examples of the divalent cyclic hydrocarbon group include the following groups (in the following groups, * means that these groups are bonded to an adjacent benzene ring at the * portion).

  Although it does not specifically limit as a bivalent coupling group represented by Z 'in the said General formula (1), What was mentioned as a preferable bivalent coupling group which Z demonstrated above represents, a bivalent aryl group, etc. Is mentioned. Preferred examples of the divalent aryl group include 1,4-phenylene, 1,3-phenylene, 1,2-phenylene, naphthalene-1,4-diyl, naphthalene-2,6-diyl and the like.

Among the compounds represented by the general formula (1),
R ¹ and R ² are an aromatic hydrocarbon group, an aromatic hydrocarbon group substituted with an aliphatic hydrocarbon group, an aromatic heterocyclic group or an aromatic heterocyclic group substituted with an aliphatic hydrocarbon group Is preferable because of its excellent fluorescence characteristics,
A compound in which X ¹ and X ² are oxygen atoms is preferable because of easy production,
The one in which Z is an alkanediyl group having 1 to 4 carbon atoms substituted with a halogen atom is preferable in terms of excellent fluorescence characteristics,
Those in which n is 0 are preferred in that they have excellent solubility in resins and solvents.

Among the compounds represented by the general formula (2) or (3),
R ⁹ and R ¹⁰ are an aromatic hydrocarbon group, an aromatic hydrocarbon group substituted with an aliphatic hydrocarbon group, an aromatic heterocyclic group or an aromatic heterocyclic group substituted with an aliphatic hydrocarbon group Is preferable in terms of excellent fluorescence characteristics,
A compound in which X ³ and X ⁴ are oxygen atoms is preferable because production is easy.

R ^{3 to} R ⁸ in the general formula (1) and R ¹¹ and R ¹² in the general formulas (2) and (3) are a hydrogen atom, an unsubstituted alkyl group, an unsubstituted aryl group, or a halogen atom. It is preferable that

  Specific examples of the benzoazole compounds represented by the general formulas (1) to (3) according to the present invention include the following compound No. Although 1-27 is mentioned, it is not restrict | limited to these compounds.

  The production method of the compound represented by the general formula (1) is not particularly limited and can be obtained by a method using a known general reaction. Examples of the production method include n in the general formula (1). Can be synthesized as shown in the following reaction formula, as in the route described in JP2008-130599A. That is, it can be synthesized by a condensation reaction of a carboxylic acid, an acid halogen compound or an aldehyde compound represented by the following general formula (4) with a compound represented by the following general formula (5).

  When n in the general formula (1) is 1 or 2, the compound represented by the general formula (1) can be synthesized as shown in the following reaction formula.

The optical filter of the present invention is suitable for use as an optical filter that absorbs light in the range of 250 to 400 nm, particularly 250 to 340 nm.
Among the optical filters of the present invention, those using a compound having wavelength conversion ability as the benzoazole dye can be used as a color conversion filter having wavelength conversion ability. The optical filter of the present invention which is a color conversion filter having wavelength conversion capability (hereinafter also referred to as the color conversion filter of the present invention) is used as a color conversion filter for converting the light having the above absorbed wavelength into light having a longer wavelength. Can do. The color conversion filter of the present invention is suitable for use as a color conversion filter that converts light in the range of 250 to 400 nm into long wavelength light in the range of 300 to 700 nm.
Among the optical filters of the present invention, those having no wavelength conversion ability can be used as a light absorption filter that absorbs light in the range of 250 to 340 nm.

  The color conversion filter of the present invention has high fluorescence quantum efficiency. Since the color conversion filter of the present invention absorbs specific ultraviolet light and converts it into light having a longer wavelength, for example, the power generation efficiency of a photoelectric conversion device can be increased.

The color conversion filter of the present invention includes, for example, an image display device such as a liquid crystal display device (LCD), a plasma display panel (PDP), a cathode ray tube display device (CRT), a fluorescent display tube, and a field emission display; It can be used as a color conversion filter used for light-emitting devices such as luminescence illumination; and photoelectric conversion devices such as solar cells.
Among the optical filters of the present invention, those that do not have wavelength conversion ability can be used as light absorption filters for the same applications as described above, but increase the power generation efficiency of the photoelectric conversion device and increase the brightness of display and illumination. It is preferable to have color conversion ability from the viewpoint of improving the effect.

  The optical filter of the present invention only needs to contain the benzoazole dye, and the configuration of the optical filter is not limited. For example, like the conventional one, it has at least a support, and if necessary, an optical function Various functional layers such as a layer, an undercoat layer, an antireflection layer, a hard coat layer, and a lubricating layer can be included. In the optical filter of the present invention, the benzoazole dye may be contained in either the support or various functional layers, and is usually preferably contained in the support or the optical functional layer. Further, the size and shape of the optical filter of the present invention are not particularly limited, and are appropriately determined according to the application.

A configuration example of a preferred embodiment of the optical filter of the present invention is shown in FIGS. For example, the optical filter includes a support 100 and an optical functional layer 120 containing the benzoazole dye, and optionally includes an undercoat layer 110, an antireflection layer 130, a hard coat layer 140, a lubricating layer 150, and the like. Can be provided. As shown in FIG. 1A, an undercoat layer 110, an optical functional layer 120, an antireflection layer 130, a hard coat layer 140, and a lubricating layer 150 may be laminated on one surface of the support 100. Alternatively, as shown in FIG. 1B, the undercoat layer 110, the optical functional layer 120, the hard coat layer 140, and the lubricating layer 150 are laminated on one surface of the support 100, and the undercoat layer is formed on the other surface. 110, the antireflection layer 130, and the lubricating layer 150 may be laminated. Alternatively, as shown in FIG. 1C, the optical filter of the present invention has an undercoat layer 110, an antireflection layer 130, a hard coat layer 140, and a hard coat layer 140 on the surface of the optical functional support 105 containing the benzoazole dye. The lubricating layer 150 may be laminated.
The optical functional layer 120 or the optical functional support 105 containing the benzoazole dye functions as a light absorption layer when the benzoazole dye does not have wavelength conversion ability, and color when the benzoazole dye has wavelength conversion ability. Functions as a conversion layer (also serves as a light absorption layer).

  Examples of the material for the support 100 include inorganic materials such as glass; polyethylene terephthalate, polymethyl methacrylate, polyvinyl butyral, polyvinyl pyrrolidone, polyvinyl alcohol, polyvinyl chloride, styrene-butadiene copolymer, polystyrene, polycarbonate, polyamide, and ethylene-acetic acid. Synthetic polymer materials such as vinyl copolymer resins, epoxy resins, polyfluorene resins, and silicon resins can be used. The support 100 is preferably a transparent support, preferably has a transmittance of 80% or more with respect to visible light, and more preferably has a transmittance of 86% or more. The haze of the support 100 is preferably 2% or less, and more preferably 1% or less. The refractive index of the support 100 is preferably 1.45 to 1.70. The thickness of the support 100 is appropriately selected depending on the application and the like, and is not particularly limited, but is usually preferably selected from the range of 10 to 10,000 μm.

  In each layer in FIG. 1, an infrared absorber, an ultraviolet absorber, inorganic fine particles, a light diffusing agent, or the like may be added. In addition, the support 100 may be subjected to various surface treatments. The surface treatment includes, for example, chemical treatment, mechanical treatment, corona discharge treatment, flame treatment, ultraviolet irradiation treatment, high frequency treatment, glow discharge treatment, active plasma treatment, laser treatment, mixed acid treatment, ozone oxidation treatment and the like.

  Further, a dye that absorbs light in other wavelength ranges can be further added to the optical function layer 120 or the optical function support 105. The dye that absorbs light in other wavelength ranges is not particularly limited. For example, cyanine dyes, pyridine dyes, oxazine dyes, coumarin dyes, coumarin dye dyes, naphthalimide dyes, pyromethene dyes, Perylene dye, pyrene dye, anthracene dye, styryl dye, rhodamine dye, azo dye, quinone dye, diketopyrrolopyrrole dye, iridium complex dye, europium dye, naphtholactam dye, etc. It is done.

  Among the dyes that absorb light in other wavelength ranges, a dye having a maximum absorption wavelength in the wavelength range of 350 to 400 nm and a maximum fluorescence wavelength in the wavelength range of 400 to 700 nm (hereinafter referred to as a combination dye) is described above. When included in the optical filter of the present invention together with a benzoazole dye, the optical filter of the present invention becomes an optical filter (color conversion filter) that converts light of 250 to 350 nm into 400 to 700 nm, and is preferable because it has a large Stoke shift. . Any of the various dyes and dyes listed above as dyes that absorb light in other wavelength ranges are useful as the combined dyes. The use ratio (the former: the latter, based on mass) of the benzoazole dye and the combination dye is preferably in the range of 1: 0.001 to 5, more preferably in the range of 1: 0.01 to 2.

  As a constituent of the optical functional layer 120 or the optical functional support 105, a binder resin such as a photocurable resin, a thermosetting resin, or a thermoplastic resin, a light diffusing agent, a light stabilizer, or a curing agent may be used as necessary. , Infrared absorber, ultraviolet absorber, antioxidant, surfactant, antistatic agent, flame retardant, lubricant, heavy metal deactivator, hydrotalcite, organic carboxylic acid, colorant, processing aid, inorganic additive, Various additives such as a filler, a clarifying agent, a nucleating agent, and a crystallization agent can be used.

  The optical functional layer 120 or the optical functional support 105 may have any form as long as it contains at least one of the benzoazole dyes. For example, the optical functional layer 120 or the optical function support 105 is made of a resin liquid in which the benzoazole dyes are dissolved or dispersed in a binder resin. The film may be obtained, or may be a single film or a laminate composed of only the azole dye. The thicknesses of the optical function layer 120 and the optical function support 105 are appropriately selected according to the use and the like, and are not particularly limited. The thickness of the body 105 is preferably selected from the range of 10 to 10,000 μm. The azole dye may be contained in an optical filter in the form of a filler, a sealant, an adhesive or the like.

  Examples of the method for producing the optical functional layer 120 or the optical functional support 105 include, for example, a vapor deposition method, a sputtering method, a dip coating method, an air knife coating after dissolving or dispersing the benzoazole dye and the binder resin in a solvent. Examples thereof include a method of forming a coating film on a permanent support or a temporary support by a method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, a spin coating method or an extrusion coating method.

  The solvent is not particularly limited, and examples thereof include water, alcohols, diols, ketones, esters, ethers, aliphatic or alicyclic hydrocarbons, aromatic hydrocarbons, and carbons having a cyano group. Examples thereof include hydrogen and halogenated aromatic hydrocarbons.

  Alternatively, as a method for producing the optical functional layer 120 or the optical functional support 105, a mixture containing the azole dye and the polymer material is extruded, cast or roll-molded to directly form a self-supporting layer. Also good. Polymer materials that can be used are cellulose esters such as diacetylcellulose, triacetylcellulose (TAC), propionylcellulose, butyrylcellulose, acetylpropionylcellulose, nitrocellulose; polyamides; polycarbonates; polyethylene terephthalate, polyethylene naphthalate, polybutylene Polyester such as terephthalate, poly-1,4-cyclohexanedimethylene terephthalate, polyethylene-1,2-diphenoxyethane-4,4′-dicarboxylate, polybutylene terephthalate; polystyrene; polyethylene, polypropylene, polymethylpentene, etc. Polyolefin; Acrylic resin such as polymethyl methacrylate; Polycarbonate; Polysulfone; Polyethersulfone Polyether ketone; polyetherimides; polyoxyethylene; norbornene resin; -; comprising polyvinyl butyral (PVB) or ethylene-vinyl acetate copolymer (EVA).

  Alternatively, after the benzoazole dye is mixed with a photocurable resin and / or a thermosetting resin and a photopolymerization initiator and / or a thermosetting agent, a cured film is formed by light irradiation and / or heat treatment. You can also.

  Alternatively, when the optical filter of the present invention is used for an application that requires patterning involving wet etching, it is produced from a composition comprising the azole dye and a photocurable or photothermal combination type curable resin (resist). I can do it. In this case, a cured product of a photocurable or photothermal combination type curable resin (resist) functions as a binder of the optical filter after patterning. In order to perform patterning smoothly, it is desirable that the photocurable or photothermal combination type curable resin is soluble in an organic solvent or an alkali solution in an unexposed state. Specifically, the photocurable or photothermal combination type curable resin (resist) that can be used includes (1) an acrylic polyfunctional monomer and oligomer having a plurality of acroyl groups and methacryloyl groups, and a photo or thermal polymerization initiator. (2) a composition comprising polyvinyl cinnamate and a sensitizer, (3) a composition comprising a chain or cyclic olefin and bisazide (nitrene is generated to crosslink the olefin) And (4) a composition comprising an epoxy group-containing monomer and an acid generator. In particular, it is preferable to use a composition comprising the acrylic polyfunctional monomer and oligomer (1) and a light or thermal polymerization initiator. This is because the composition is capable of high-definition patterning and has high reliability such as solvent resistance and heat resistance after being polymerized and cured.

In the optical filter of the present invention, particularly the color conversion filter, the amount of the benzoazole dye used is usually within the range of 1 to 10,000 mg / m ² , preferably within the range of 10 to 3000 mg / m ² per unit area of the filter. It is desirable to do. By setting the amount to be used in such a range, a sufficient color conversion effect is exhibited, and an appropriate color conversion efficiency and photoelectric conversion effect are exhibited in the color conversion light-emitting device and the photoelectric conversion device of the present invention. In order to satisfy the preferred amount of use per unit area, for example, the amount of the benzoazole dye is 0.001 to 10 parts by mass in 100 parts by mass of the binder resin, depending on the type of binder resin used. It is desirable to form the optical functional layer 120 or the optical functional support 105 having a thickness in the above-described preferable range using a resin liquid. The amount of the benzoazole dye used is preferably such that the absorbance at λmax of the optical filter is 0.01 to 1.0.

  The antireflection layer 130 is a layer for preventing reflection by the optical filter and improving light transmittance. The antireflection layer 130 may be a low refractive index layer formed of a material having a lower refractive index than the support 100. The refractive index of the low refractive index layer is preferably 1.20 to 1.55, and more preferably 1.30 to 1.50. The thickness of the low refractive index layer is preferably 50 to 400 nm, and more preferably 50 to 200 nm. The low refractive index layer can be formed as a layer made of a fluorine-containing polymer having a low refractive index, a layer obtained by a sol-gel method, or a layer containing fine particles. In the layer containing fine particles, voids can be formed in the low refractive index layer as microvoids between or within the fine particles. The layer containing fine particles preferably has a porosity of 3 to 50% by volume, and more preferably has a porosity of 5 to 35% by volume.

  By forming the antireflection layer 130 from a laminate of one or more low refractive index layers and one or more medium / high refractive index layers, light reflection in a wider wavelength region can be prevented. The refractive index of the high refractive index layer is preferably 1.65 to 2.40, and more preferably 1.70 to 2.20. The refractive index of the middle refractive index layer is adjusted to be an intermediate value between the refractive index of the low refractive index layer and the refractive index of the high refractive index layer. The refractive index of the medium refractive index layer is preferably 1.50 to 1.90, and more preferably 1.55 to 1.70. The thickness of the middle / high refractive index layer is preferably 5 nm to 100 μm, more preferably 10 nm to 10 μm, and most preferably 30 nm to 1 μm. The haze of the medium / high refractive index layer is preferably 5% or less, more preferably 3% or less, and most preferably 1% or less, except for the case where the antiglare function described later is imparted. .

  The middle / high refractive index layer can be formed using a polymer binder having a relatively high refractive index. Examples of polymers having a high refractive index include polystyrene, styrene copolymer, polycarbonate, melamine resin, phenolic resin, epoxy resin, and polyurethane obtained by reaction of cyclic (alicyclic or aromatic) isocyanate and polyol. It is. Polymers having other cyclic (aromatic, heterocyclic, alicyclic) groups and polymers having a halogen atom other than fluorine as a substituent also have a high refractive index. The polymer may be formed by a polymerization reaction of a monomer in which a double bond is introduced to enable radical curing.

  In order to obtain a higher refractive index, inorganic fine particles may be dispersed in the polymer binder. The refractive index of the inorganic fine particles to be dispersed is preferably 1.80 to 2.80. Inorganic fine particles are formed from oxides or sulfides of metals such as titanium dioxide (eg, rutile, rutile / anatase mixed crystal, anatase, amorphous structure), tin oxide, indium oxide, zinc oxide, zirconium oxide and zinc sulfide. It is preferable to do. Titanium oxide, tin oxide and indium oxide are particularly preferred. The inorganic fine particles are mainly composed of oxides or sulfides of these metals, and can further contain other elements. The main component means a component having the largest content (% by weight) among the components constituting the particles. Examples of other elements include Ti, Zr, Sn, Sb, Cu, Fe, Mn, Pb, Cd, As, Cr, Hg, Zn, Al, Mg, Si, P, and S. Alternatively, an inorganic material that is film-forming and can be dispersed in a solvent, or is itself a liquid, such as alkoxides of various elements, salts of organic acids, coordination compounds bonded to coordination compounds (eg, chelate compounds) ), An intermediate / high refractive index layer can be formed using an active inorganic polymer.

  The antireflection layer 130 can provide an antiglare function (a function of scattering incident light on the surface and preventing the scenery around the film from moving to the film surface) on the surface. For example, by forming fine irregularities on the surface (for example, the roughened undercoat layer 110) on which the antireflection layer 130 is formed, or by forming irregularities on the surface of the antireflection layer 130 by an embossing roll or the like. Anti-glare function can be added. The antireflection layer 130 having an antiglare function generally has a haze of 3 to 30%.

  The hard coat layer 140 is a layer for protecting the layer (the optical function layer 120 and / or the antireflection layer 130) formed thereunder, and is formed of a material having a hardness higher than that of the support 100. The hard coat layer 140 preferably contains a crosslinked polymer. The hard coat layer can be formed using an acrylic, urethane, or epoxy polymer, oligomer, or monomer (eg, an ultraviolet curable resin). The hard coat layer 140 can also be formed from a silica-based material.

  The lubricating layer 150 may be formed on the surface of the optical filter. The lubricating layer 150 has a function of imparting slipperiness to the optical filter surface and improving scratch resistance. The lubricating layer 150 can be formed using polyorganosiloxane (eg, silicone oil), natural wax, petroleum wax, higher fatty acid metal salt, fluorine-based lubricant, or a derivative thereof. The thickness of the lubricating layer 150 is preferably 2 to 20 nm.

  The undercoat layer 110, the antireflection layer 130, the hard coat layer 140, and the lubricating layer 150 are formed by a dip coating method, an air knife coating method, a curtain coating method, a roller coating method, a wire bar coating method, a gravure coating method, and an extrusion. It can be formed by any coating method known in the art, such as a coating method. When the hard coat layer 140 is formed from a silica-based material, the hard coat layer 140 may be formed using any film forming technique known in the technical field, such as vapor deposition, sputtering, CVD, or laser ablation. Good.

  Each constituent layer of the optical filter may be sequentially formed one by one in accordance with the stacking order, or two or more layers may be formed by a simultaneous coating method.

Next, a color conversion light emitting device using the color conversion filter of the present invention will be described.
The color conversion light-emitting device of the present invention is not particularly limited as long as it has the light-emitting part (light source) and the color conversion filter of the present invention as the color conversion part, and the configuration according to the conventional color conversion light-emitting device It can be. As the light emitting part, any light source that emits light from the near ultraviolet to the visible region, preferably from the near ultraviolet to blue-green, can be used. Examples of such a light source include an organic EL light emitting device, a plasma light emitting device, a cold cathode tube, a discharge lamp (such as a high pressure / ultra high pressure mercury lamp and a xenon lamp), a light emitting diode, and the like.

  FIGS. 2A to 2C are schematic cross-sectional views showing a preferred embodiment of a ballistic LED device which is an example of a color conversion light-emitting device using the color conversion filter of the present invention. An example of the color conversion light-emitting device shown in FIGS. 2A to 2C is used for an illumination device using an LED as a light source. The leads 2 and 3 are formed of copper or a copper alloy having excellent thermal conductivity and conductivity. The wire 4 connects the leads 2 and 3 and the LED element 6, and gold is used. As the LED element 6, a known element can be used. For example, GaN-based, InGaN-based, AlP-based, AlInGaN-based and the like can be cited as elements that emit blue light.

  For the sealing resin 1 and / or the sealing resin 5, an epoxy resin and / or a silicon resin or the like is used. The sealing resin 5 is mixed with a phosphor. As the phosphor, an inorganic compound that emits fluorescence such as yellow, yellow + red, green + red, or the like is used.

In the ballistic LED device of FIG. 2A, a benzoazole dye is mixed with the sealing resin 1 and / or the sealing resin 5. That is, in the ballistic LED device of FIG. 2A, the sealing resin 1 and / or the sealing resin 5 portion is the color conversion filter of the present invention.
In the ballistic LED device, a color conversion layer may be provided. 2 (b) and 2 (c) are examples of ballistic LED devices provided with a color conversion layer. In FIG. 2 (b), a color conversion layer 7 is provided, and in FIG. 2 (c) A color conversion layer 8 is provided. In the ballistic LED devices of FIGS. 2B and 2C, these color conversion layers are the color conversion filters of the present invention. For example, from the same manufacturing method and material as the color conversion filter described in FIG. Thus, various functional layers may be provided as necessary.
In the color conversion light-emitting device of the present invention, the benzoazole dye according to the present invention may be used for at least one of the sealing resin 1, the sealing resin 5, the color conversion layer 7, and the color conversion layer 8 described above.

Further, as another example of the color conversion light emitting device using the color conversion filter of the present invention, FIGS. 2D to 2F show examples of a color conversion light emitting device (illumination device) in which LED chips are arranged.
For example, in the color conversion light-emitting device of FIG. 2D, the LED chip 330 is installed on the substrate 300 (however, it may be arbitrarily installed on a plane as well as a straight line), and the space between the counter substrate 320 is sealed. Sealed with a stop resin 310. In the color conversion light-emitting device of FIG. 2D, the benzoazole dye according to the present invention is mixed with the sealing resin 310. That is, in the color conversion light emitting device of FIG. 2D, the sealing resin 310 portion is the color conversion filter of the present invention.
In the color conversion light-emitting devices of FIGS. 2 (e) and 2 (f), a color conversion layer 340 containing the benzoazole dye according to the present invention is provided or functioned on or under the counter substrate. That is, in the color conversion light emitting device of FIGS. 2E and 2F, the color conversion layer 340 portion is the color conversion filter of the present invention. In the color conversion light-emitting devices shown in FIGS. 2E and 2F, the benzoazole dye may be used for the sealing resin 310.

  FIG. 3 shows a color conversion light-emitting device for a color display as still another example of the color conversion light-emitting device using the color conversion filter of the present invention. In the color conversion light emitting device shown in FIG. 3, the light emitting layer 40 is provided on the support 50. The method for causing the light emitting layer 40 to emit light is not limited. For example, in the case of an EL (electroluminescence) element, light can be emitted by sandwiching the light emitting layer between electrodes and passing a current.

  Further, by providing the red, green, and blue color conversion layers 20R, 20G, and 20B on the light emitting layer 40, the light emitted from the light emitting layer 40 can be color-converted. At least one of these color conversion layers is the color conversion filter of the present invention. The color conversion filter can appropriately be red, green, and blue color conversion layers 20R, 20G, and 20B depending on the wavelength after conversion. As the color conversion layer, for example, a color conversion filter composed of a film obtained from a resin solution in which a benzoazole dye is dissolved or dispersed in a binder resin can be employed.

  Further, red, green, and blue color filter layers 10R, 10G, and 10B can be provided as appropriate. These color filter layers are provided as necessary in order to optimize the color coordinates or the color purity of the light converted by the red, green, and blue color conversion layers 20R, 20G, and 20B.

  As the material of the support 50, for example, inorganic materials such as glass and synthetic polymer materials mentioned as the material of the support 100 in the optical film of the present invention can be used. In order to appropriately produce an electrode for emitting light from the light emitting layer 40, glass is preferable as a support on which the electrode is easily formed.

  Each color filter layer 10R, 10G, and 10B has a function of transmitting only light in a desired wavelength range. The color filter layers 10R, 10G, and 10B for each color block light from the light source that has not been subjected to wavelength distribution conversion by the color conversion layers 20R, 20G, and 20B, and are subjected to wavelength distribution conversion by the color conversion layers 20R, 20G, and 20B. This is effective for improving the color purity of light. These color filter layers may be formed using, for example, a color filter material for a liquid crystal display.

  By using the RGB color conversion light-emitting device shown in FIG. 3 as a set of pixels and arranging a plurality of pixels in a matrix on a support, a color conversion light-emitting device for a color display can be formed. The desired pattern of the color conversion layer depends on the application used. A set of red, green, and blue rectangular or circular or intermediate areas may be formed on the entire surface of the transparent support in a matrix. Alternatively, a single color that cannot be achieved by a single color conversion layer may be displayed by using two types of color conversion layers arranged in an appropriate area ratio divided into minute areas.

  In the example of FIG. 3, the case where the RGB color conversion layers are provided is shown. However, when a light emitting element that emits blue light is used as a light source, only the color filter layer is used for blue without using the color conversion layer. May be used.

In the color conversion light-emitting device of the present invention, when a color filter layer is provided as shown in FIG. 3, the light-emitting portion is disposed on the color conversion layer side.
In the color conversion light emitting device of the present invention, when the color conversion filter shown in FIG. 1 (without the color filter layer) is used as the color conversion unit without providing the color filter layer, for example, the light emission unit is a color conversion filter. The color conversion filter may be directly laminated on the surface of the light source.

Next, a color conversion light emitting device using the color conversion filter of the present invention will be described.
The photoelectric conversion device of the present invention is not particularly limited as long as it has a photoelectric conversion element and the color conversion filter of the present invention, and can be configured according to a conventional photoelectric conversion device. FIG. 4 shows a solar cell as an example of the photoelectric conversion device of the present invention. In the solar cell of FIG. 4, the photoelectric conversion element 240 is selected from the surface sheet layer 200, the transparent substrate 210, the filler layer 220, the condensing film 230, and the back sheet layer 250 around the element so that the photoelectric conversion element 240 can generate power with high efficiency. One or more members can be converted into a color conversion filter. That is, by including a benzoazole dye in the peripheral member of the photoelectric conversion element, the peripheral member can be used as the color conversion filter of the present invention. In addition to the above-described layers shown in FIG. 4, a color conversion filter layer as the color conversion filter of the present invention may be separately formed. For example, an adhesive containing a benzoazole dye is used between the layers. The same effect can be obtained by forming an adhesive layer that functions as a color conversion filter layer.

The photoelectric conversion device of the present invention is not particularly limited, for example, single crystal form, a polycrystalline form, silicon solar cell amorphous silicon type such as; GaAs-based, CIS system, Cu ₂ ZnSnS ₄ system, CdTe-CdS system, etc. Compound-based solar cells: Solar cells such as dye-sensitized and organic thin-film organic solar cells.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited by the following examples.

[Synthesis Example 1] Compound No. 1 Synthesis of 1 1.2 g of benzoic acid, 1.5 g of 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, and 13 g of polyphosphoric acid were reacted at 180 ° C. for 5 hours. After cooling to 90 ° C., the reaction solution was poured into 300 ml of water and stirred at room temperature for 10 hours. The precipitated solid was filtered, washed with water, and further dispersed and washed with an aqueous sodium hydroxide solution. The solid was purified by silica gel column chromatography with a toluene solvent, crystallized with methanol, washed with acetone, and then vacuum dried to obtain 1.0 g of the white solid (yield 46%).
The obtained compound was identified by ¹ H-NMR and mass spectrometry (MARDI-TOF-MS). These results are shown in the following [Table 1] and [Table 2].

[Synthesis Example 2] Compound No. <Step 1> Synthesis of Intermediate 1 4-Bromobenzoic acid 22.1 g, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane 18.3 g, and polyphosphoric acid 208 g at 130 ° C. The reaction was carried out for 4 hours at 180 ° C. for 10 hours. After cooling to 80 ° C., the reaction solution was poured into 1 L of water and stirred at room temperature for 3 hours. The precipitated solid was filtered, washed with water, and further dispersed and washed with an aqueous sodium hydroxide solution. The solid was dispersed and washed with methanol and then vacuum-dried to obtain 34.3 g (yield 98.5%) of Intermediate 1 (see below) as a white solid.
<Step 2> Compound No. Synthesis of 2 0.7 g of Intermediate 1 obtained in Step 1, 0.3 g of phenylboronic acid, 11 mg of palladium (II) acetate, 40 mg of triphenylphosphine, 0.3 g of sodium carbonate, 5.0 g of toluene, water 3.5 g was charged and reacted at 100 ° C. for 7 hours under an argon atmosphere. After cooling to near room temperature and oil-water separation, the oil phase was purified by silica gel column chromatography with a toluene solvent, and after crystallization from methanol, 0.3 g (yield 37%) was obtained by vacuum drying. The obtained compound was identified in the same manner as in Synthesis Example 1. The results are shown in [Table 1] and [Table 2] below.

[Synthesis Example 3] Compound No. 3 except that phenylboronic acid in Step 2 of Synthesis Example 2 was changed to 0.4 g of 4-trifluoromethylphenylboronic acid, the amount of toluene was changed to 5.8 g, and the amount of water was changed to 4.2 g. In the same manner as in Synthesis Example 2, 0.8 g (yield 96%) of a white solid was obtained. The obtained compound was identified in the same manner as in Synthesis Example 1. The results are shown in [Table 1] and [Table 2] below.

[Synthesis Example 4] Compound No. 4 Synthesis Example 4 Synthesis Example 2 except that phenylboronic acid in Step 2 of Synthesis Example 2 was changed to 0.4 g of 4-methoxyphenylboronic acid, the amount of toluene was changed to 4.2 g, and the amount of water was changed to 3.0 g. In the same manner as in No. 2, 0.4 g (yield 67%) of a white solid was obtained. The obtained compound was identified in the same manner as in Synthesis Example 1. The results are shown in [Table 1] and [Table 2] below.

[Examples 1 to 5 and Comparative Example 1]
A test compound shown in Table 1 was dissolved in a toluene solution of 25 wt% polymethyl methacrylate prepared in advance so that the absorbance at λmax was 0.5, and a wire bar (RDS30 RDS Webster, N.D. Y.) was applied to a 100 μm polyethylene terephthalate (PET) film substrate, and then heated in an oven at 100 ° C. for 10 minutes to obtain the color conversion filter of the present invention. In Table 1, the compound no. 2 and comparative compound no. The ratio with 1 is based on mass.
For the obtained color conversion filter, the absorption spectrum was measured using a spectrophotometer U-3010 manufactured by Hitachi High-Technologies Co., Ltd., and the fluorescence spectrum was measured using a spectrofluorophotometer F4500 manufactured by Hitachi High-Technologies Co., Ltd. It was measured. The quantum efficiency was calculated from the area ratio by measuring the vicinity of λmax of each film as excitation light using an absolute PL quantum yield measuring device C9920-02G manufactured by Hamamatsu Photonics. The results are shown in [Table 3] below.

[Examples 6 and 7 and Comparative Examples 2 and 3]
A color conversion filter described in Table 2 was placed and fixed on the light receiving surface of the solar cell to obtain a photoelectric conversion device. Spectral sensitivity measurement (IPCE measurement) was performed on the obtained photoelectric conversion device, and values at 320 nm and 400 nm were read from the spectral sensitivity curve. The results are shown in [Table 4]. In Comparative Example 3, a filter made of only polymethylmethacrylate containing no pigment was used as a blank.

In Comparative Example 3, since the filter does not contain a dye for wavelength conversion, the photoelectric conversion efficiency at 320 nm is very low, whereas in Example 6, the color conversion filter converts light into a long wavelength (Table Therefore, the photoelectric conversion efficiency at 320 nm is high. In Example 6, the photoelectric conversion efficiency at 400 nm is maintained at the same level as in Comparative Example 3.
In Comparative Example 2, the photoelectric conversion efficiency at 320 nm was improved as compared with Comparative Example 3, but Comparative Compound No. 1 contained in the color conversion filter was used. 1, the photoelectric conversion efficiency at 400 nm is significantly lower than that of Comparative Example 3 due to absorption around 400 nm (see Table 3).
In Example 7, since the color conversion filter has a large Stoke shift (see Table 3), 320 nm light is converted to a wavelength with higher photoelectric conversion efficiency, and the photoelectric conversion efficiency at 320 nm is higher than that of Example 6. Although the photoelectric conversion efficiency at 400 nm is slightly reduced, the decrease width is small and a good level is maintained.

  From the above, it is clear that the color conversion filter of the present invention is suitable for a photoelectric conversion device and a color conversion light-emitting device because it has color conversion capability. It is apparent that the color conversion filter of the present invention is particularly preferable for a photoelectric conversion device because it can effectively use light in a short wavelength region where the electromotive force of the solar cell is extremely small.

DESCRIPTION OF SYMBOLS 1 Sealing resin 2 Lead 3 Lead 4 Wire 5 Sealing resin 6 LED element 7 Color conversion layer 8 Color conversion layer 10R Red filter layer 10G Green filter layer 10B Blue filter layer 20R Red conversion layer 20G Green conversion layer 20B Blue conversion layer 30 Black mask 40 Light emitting layer 50 Support body 100 Support body 105 Optical function support body 110 Undercoat layer 120 Optical function layer 130 Antireflection layer 140 Hard coat layer 150 Lubricating layer 200 Surface sheet layer 210 Transparent substrate 220 Filler layer 230 Condensing film 240 Photoelectric conversion element 250 Back sheet layer 300 Substrate 310 Sealing resin 320 Counter substrate 330 LED chip 340 Color conversion layer

Claims (6)

  An optical filter comprising at least one benzoazole dye having at least two azole rings. The optical filter according to claim 1, wherein the benzoazole dye having at least two azole rings is a compound represented by the following general formula (1).

Z in the general formula (1) is an alkanediyl group having 1 to 4 carbon atoms which may be substituted with a halogen atom, or a divalent ring having 3 to 20 carbon atoms which may be substituted with a halogen atom. The optical filter according to claim 2, wherein n is 0, which is a formula hydrocarbon group, —O—, —S—, —SO ₂ —, —SS—, —SO—, —CO— or —OCO—.   The optical filter according to any one of claims 1 to 3, which is a color conversion filter having wavelength conversion ability.   The color conversion light-emitting device containing a light emission part and the optical filter of Claim 4.   A photoelectric conversion device comprising a photoelectric conversion element and the optical filter according to claim 4.

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