JP2017082063A - Light wavelength conversion element comprising deep eutectic solvent and article comprising the light wavelength conversion element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a light wavelength conversion element at a low cost.SOLUTION: In a light wavelength conversion element, an organic photosensitizing molecule (A) and an organic luminescent molecule (B), which is a combination showing a triplet-triplet annihilation process, are dissolved and/or dispersed in a deep eutectic solvent (C).SELECTED DRAWING: None

Description

  The present invention relates to a light wavelength conversion element containing a deep eutectic solvent and an article (solar cell, photocatalyst, photocatalytic hydrogen / oxygen generator, and light upconversion filter) including the light wavelength conversion element.

  While there is a strong need for alternative energy such as global warming countermeasures and clean energy, technology development to convert sunlight into secondary energy (electric power, hydrogen, etc.) with high efficiency is an urgent task. Expectations for light-secondary energy conversion elements (elements that convert light into secondary energy) such as solar cells with high light-secondary energy conversion efficiency (light-to-secondary energy conversion efficiency) and hydrogen-generating photocatalysts Is growing. Light-secondary energy conversion elements, such as general solar cells and hydrogen-generating photocatalysts, have a certain threshold wavelength that is unique to the light-secondary energy conversion element among light in a wide wavelength range included in sunlight. Only short wavelength components are used for conversion, and components longer than the threshold wavelength are unused. Therefore, as one of the technologies for effectively using light in a wide wavelength range included in sunlight, light up-conversion (that is, light by absorbing light of a long wavelength and emitting light of a shorter wavelength) Are being studied.

  As a means of optical up-conversion, research on optical up-conversion using multiphoton absorption of rare earth elements has a history of more than 50 years. However, multi-photon absorption of rare earth elements generally requires a very high incident light intensity, and it has been difficult to convert weak light such as sunlight as a target for conversion.

  In recent years, organic molecules that can perform optical up-conversion by light absorption and emission have been published.

The present inventors have provided a light wavelength conversion element obtained by dissolving and / or dispersing an organic photosensitizer molecule and an organic light emitting molecule in an ionic liquid in light upconversion using a triplet-triplet annihilation (TTA) process. (Patent Document 1).

  On the other hand, a deep eutectic solvent is known as an organic fluid of a relatively new category completely different from the ionic liquid in terms of material definition. The deep eutectic solvent is described in, for example, Non-Patent Documents 1 to 3 which are review papers regarding deep eutectic solvents and Non-Patent Documents 4 and 5 which are papers related to deep eutectic solvents.

International Publication No. 2012/050137

Q. Zhang et al., Chem. Soc. Rev., 2012, 41, p.7108-7146 A. Paiva et al., ACS Sustain. Chem. Eng., 2014, 2, p.1063-1071 D. V. Wagle et al., Account Chem. Res., 2014, 47, p.2299-2308 F. S. Mjalli et al., J. Chem. Eng. Data, 2014, 59, p.2242-2251 L. F. Zubeir et al., J. Phys. Chem. B, 2014, 118, p.14429-14441

  However, the optical wavelength conversion element of Patent Document 1 generally uses an ionic liquid that is high in cost, and this point has become a major obstacle to realizing the application when envisioning mass use in application. .

  The present invention has been made with the aim of solving the main obstacles to realizing the application in such an existing invention, and the object thereof is an optical wavelength conversion element having the possibility of drastic cost reduction, and The object is to provide an article (a solar cell, a photocatalyst, a photocatalytic hydrogen / oxygen generator, and an optical up-conversion filter) including the light wavelength conversion element.

  In order to solve the above-mentioned problem, the light wavelength conversion element of the present invention has a combination of an organic photosensitizer molecule (A) and an organic light emitting molecule (B), which are a combination showing a triplet-triplet annihilation (TTA) process. It is characterized by being dissolved and / or dispersed in the crystal solvent (C).

  Here, in the present application document, the “deep eutectic solvent” is a mixture of a salt and a hydrogen bond donor, and means a mixture whose melting point is greatly lowered by the eutectic. It should be noted that “deep eutectic solvent” is completely different from “ionic liquid”. (Since they are rarely confused in academic journals and academic society publications, it is stated here that they are different in substance classification.) That is, “Ionic liquid "" Supervised by Hiroyuki Ohno, "Ionic Liquid II-Amazing Progress and Various Near Futures", CMC Publishing Co., Ltd., March 30, 2006, p.4-7 "and" RD Rogers and KR As described in Seddon, “Ionic Liquids-solvents of the Future?” Science, vol. 302, no. 5646, p. 792-793, 2003 ”,“ Liquids consisting only of ions ”,“ 100% ions ” It is a substance defined as "a liquid electrolyte consisting of" or "completely consisting of ions." That is, the “deep eutectic solvent” is “not composed of only ions” in that it contains a hydrogen bond donor, and thus is not an “ionic liquid” in the definition on the substance. For supporting this point, for example, p. In the eleventh row on the right column of 7109, “(1) DES (abbreviation of deep eutectic solvent) does not consist entirely of ionic species, and (2) DES can also be obtained from non-ionic species. DES cannot be regarded as IL (abbreviation for ionic liquid).

  A deep eutectic solvent is a medium that retains low volatility and flame ignitability, and is significantly lower in cost than an ionic liquid (2 to 3 digits are considered to be low in cost as judged from the composition raw material). . Therefore, the optical wavelength conversion element of the present invention effectively solves the cost problems and problems caused by mass use in application in the optical wavelength conversion element using the ionic liquid in the prior invention (Patent Document 1). It is what. In addition, ionic liquids are generally not biodegradable, whereas deep eutectic solvents are generally composed of biodegradable, low-environmental raw materials. There are advancements and advantages that can realize the wavelength conversion element.

  In the application documents, “dissolving and / or dispersing” means either dissolving or dispersing, or dissolving and dispersing at the same time.

  The solar cell of the present invention is characterized by using the light wavelength conversion element. Since the solar cell of the present invention uses a low-cost optical wavelength conversion element, it solves the problems and problems that have been the main obstacles to application in the conventional invention technology.

  The photocatalyst of the present invention is characterized by using the light wavelength conversion element. Since the photocatalyst of the present invention uses a low-cost optical wavelength conversion element, it solves the problems and problems that have been the main obstacles to application in the conventional invention technology.

  The photocatalytic hydrogen / oxygen generator of the present invention is characterized by using the light wavelength conversion element. Since the photocatalytic hydrogen / oxygen generator of the present invention uses a low-cost light wavelength conversion element, it solves the problems and problems that have been the main obstacles to application in the conventional invention technology.

  The optical up-conversion filter of the present invention is an optical up-conversion filter that converts light into light having a shorter wavelength, and includes the optical wavelength conversion element and a cell serving as a sealing / holding shell thereof, The wavelength conversion element is encapsulated in the cell. Since the optical up-conversion filter of the present invention uses a low-cost optical wavelength conversion element, it solves the problems and problems that have been the main obstacles to application in the conventional invention technology.

  According to the present invention, it is possible to provide a low-cost light wavelength conversion element and an article (solar cell, photocatalyst, photocatalytic hydrogen / oxygen generator, and light up-conversion filter) including the light wavelength conversion element.

It is sectional drawing which shows the solar cell which concerns on an example of implementation of this invention. It is sectional drawing which shows the photocatalyst based on an example of implementation of this invention. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 1. FIG. FIG. 3 is a diagram showing an up-conversion emission spectrum of the light wavelength conversion element obtained in Example 1. It is a figure which shows the light absorption spectrum of the optical wavelength conversion element obtained in Example 2. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 2. FIG. It is a figure which shows the mode of light emission of the light wavelength conversion element obtained in Example 2. FIG. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 3. FIG. 6 is a diagram showing an up-conversion emission spectrum of the light wavelength conversion element obtained in Example 3. FIG. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 4. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 4. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 5. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 5. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 6. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 6. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 7. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 7. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 8. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 8. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 9. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 9. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 10. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 10. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 11. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 11. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 12. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 12. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 13. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 13. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 14. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 14. It is a figure which shows the light absorption spectrum of the light wavelength conversion element obtained in Example 15. FIG. It is a figure which shows the up-conversion emission spectrum of the light wavelength conversion element obtained in Example 15.

  Hereinafter, the present invention will be described in more detail.

  In the light wavelength conversion element of the present invention, the organic photosensitizing molecule (A) and the organic light emitting molecule (B), which are a combination showing a triplet-triplet annihilation process, are dissolved and / or dissolved in the deep eutectic solvent (C). Is distributed.

  The organic photosensitizer molecule (A) and the organic light emitting molecule (B) can be used without limitation as long as the combination exhibits a TTA process (light emission based on the TTA process). The absorption wavelength of the organic photosensitizer molecule (A) and the emission wavelength of the organic light emitting molecule (B) can be selected without limitation from within the wavelength range of sunlight. For example, in the light wavelength conversion element that up-converts light in the visible to near infrared region, a π-conjugated molecule having a light absorption band in the visible to near infrared region is used as the organic photosensitizer molecule (A). A π-conjugated molecule having an emission band in the visible to near-infrared region can be used as the organic light-emitting molecule (B). Examples of the organic photosensitizing molecule (A) and the organic light emitting molecule (B) include aromatic π electron conjugated compounds, particularly polycyclic aromatic π electron conjugated compounds, and the like. Baluschev, et al. , New Journal of Physics, vol. 10, p. Low molecules and polymers can be widely used, including the compounds described in 013007-1 to 0130007-12, 2008.

  The organic photosensitizer molecule (A) can be used without limitation as long as it has an absorption maximum wavelength in the wavelength range of sunlight, but usually has an absorption maximum wavelength in the range of 200 to 1000 nm. Is used. As said organic photosensitizer molecule (A), you may use what has an absorption maximum wavelength in the range of 500-700 nm. As a result, light having a relatively long wavelength that is not used in a light-secondary energy conversion element such as a general solar cell or a hydrogen generation photocatalyst can be converted into a light having a relatively short wavelength that is used in a general light-secondary energy conversion element. Therefore, light in a wide wavelength range included in sunlight can be effectively used by the light-secondary energy conversion element. Moreover, you may use what has an absorption maximum wavelength in the range of 250-499 nm as said organic photosensitizer molecule | numerator (A). This makes it possible to effectively use light having wavelengths in the blue region, the purple region, and the ultraviolet region.

  As the organic photosensitizing molecule (A), any molecular species that has not been called a dye can be used as long as it has light absorption in the range from the ultraviolet region to the infrared region. Examples of the organic photosensitizer molecule (A) include acenaphthene derivatives, acetophenone derivatives, anthracene derivatives, diphenylacetylene derivatives, acridan derivatives, acridine derivatives, acridone derivatives, thioacridone derivatives, angelicin derivatives, anthracene derivatives, anthraquinone derivatives, azafluorenes. Derivatives, azulene derivatives, benzyl derivatives, carbazole derivatives, coronene derivatives, sumanene derivatives, biphenylene derivatives, fluorene derivatives, perylene derivatives, phenanthrene derivatives, phenanthroline derivatives, phenazine derivatives, benzophenone derivatives, pyrene derivatives, benzoquinone derivatives, biacetyl derivatives, bianthranyl derivatives , Fullerene derivatives, graphene derivatives, carotene derivatives, chlorophyll derivatives, Derivatives, cinnoline derivatives, coumarin derivatives, curcumin derivatives, dansylamide derivatives, flavone derivatives, fluorenone derivatives, fluorescein derivatives, helicene derivatives, indene derivatives, lumichrome derivatives, lumiflavin derivatives, oxadiazole derivatives, oxazole derivatives, perifuranthene derivatives, perylene derivatives Phenanthrene derivatives, phenanthroline derivatives, phenazine derivatives, phenol derivatives, phenothiazine derivatives, phenoxazine derivatives, phthalazine derivatives, phthalocyanine derivatives, picene derivatives, porphyrin derivatives, porphycene derivatives, hemiporphycene derivatives, subphthalocyanine derivatives, psoralen derivatives, angelicin derivatives, purines Derivatives, pyrene derivatives, pyromethene derivatives, pyridyl ketone derivatives , Phenyl ketone derivatives, pyridyl ketone derivatives, thienyl ketone derivatives, furanyl ketone derivatives, quinazoline derivatives, quinoline derivatives, quinoxaline derivatives, retinal derivatives, retinol derivatives, rhodamine derivatives, riboflavin derivatives, rubrene derivatives, squalene derivatives, stilbene derivatives, tetracene derivatives, Pentacene derivative, anthraquinone derivative, tetracenequinone derivative, pentacenequinone derivative, thiophosgene derivative, indigo derivative, thioinzogo derivative, thioxanthene derivative, thymine derivative, triphenylene derivative, triphenylmethane derivative, triaryl derivative, tryptophan derivative, uracil derivative, xanthene derivative , Ferrocene derivatives, azulene derivatives, biacetyl derivatives, terphenyl derivatives, Examples include, but are not limited to, terfuran derivatives, terthiophene derivatives, oligoaryl derivatives, fullerene derivatives, conjugated polyene derivatives, 14-group element condensed polycyclic aromatic compound derivatives, and condensed polycyclic heteroaromatic compound derivatives. is not.

Specific examples of the organic photosensitizing molecule (A) include metal porphyrins (metal complexes of porphyrins); metal tetraazaporphyrins; metal phthalocyanines; and iodine derivatives of 3,5-dimethyl-boron dipyrromethene. Boron dipyrromethenes such as iodine derivatives of 3,5-dimethyl-8-phenylboron dipyrromethene; Schiff base metal complexes such as salen metal complexes; metals such as rubidium-bipyridine complexes and iridium-phenanthroline complexes; Bipyridine complexes; metal phenanthroline complexes; naphthalenediimides such as N-alkylnaphthalenediimide; acridones such as N-methylacridone and N-butyl-2-chloroacridone; 2,4-diethylthioxanthone and the like Thioxanthones, xanthones, xanthenes Acridines such as acridine yellow; coumarins such as coumarin 6 and coumarin 314; biacetyls such as 2,3-butanedione; 9,10-dibromoanthracene, 9,9′-bianthryl and the like Anthracenes; oligoaryls such as bifuran, bithiophene, bis (benzoxazolyl) thiophene; condensed polycyclic heteroaromatic compounds such as chrysene, phenanthrene or derivatives thereof, etc. It is not done. As a metal atom contained in the metal porphyrins and metal phthalocyanines, Pt, Pd, Ru, Rh, Ir, Zn, Cu and the like can be used. Examples of the metal tetraazaporphyrins include metal tetraazaporphyrins having a structure in which carbon atoms at positions 5, 10, 15, and 20 in the general formula (5) described later and R ⁸ bonded thereto are replaced with nitrogen atoms. .

  Among the examples of the organic photosensitizing molecule (A), examples of the organic photosensitizing molecule (A) having an absorption maximum wavelength in the range of 500 to 700 nm and containing a metal in the structure thereof include the following general Formula (5)

(In the formula, each R ⁷ represents an arbitrary substituent containing a hydrogen atom, R ⁷ may be the same or different, and two adjacent R ^{7 s} connected to each other are connected to each other to contain an optional hydrogen atom. may form a 5- or 6-membered ring containing the group, each R ⁸ represents an aryl group having a substituent containing a hydrogen atom, R ⁸ may be the same or different, M is Represents a metal atom)
The compound represented by these is mentioned. Here, the “arbitrary substituent containing a hydrogen atom” means a hydrogen atom or an arbitrary substituent other than a hydrogen atom.

Examples of R ^{7 in} the general formula (5) include hydrogen atom, alkyl group (for example, alkyl group having 1 to 12 carbon atoms), alkenyl group, alkynyl group, halogen atom, hydroxy group (hydroxyl group), alkylcarbonyloxy. Group, arylcarbonyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, carboxylate, alkylcarbonyl group, arylcarbonyl group, alkoxycarbonyl group, aminocarbonyl group, alkylaminocarbonyl group, dialkylaminocarbonyl group, alkylthiocarbonyl Group, alkoxyl group, phosphate group, phosphonate group, phosphinate group, cyano group, amino group (including alkylamino group, dialkylamino group, arylamino group, diarylamino group, and alkylarylamino group), Silamino group (including alkylcarbonylamino group, arylcarbonylamino group, carbamoyl group, and ureido group), amidino group, imino group, sulfhydryl group, alkylthio group, arylthio group, thiocarboxylate group, sulfate group, alkylsulfinyl group, Examples include, but are not limited to, sulfonate groups, sulfamoyl groups, sulfonamido groups, nitro groups, trifluoromethyl groups, cyano groups, azide groups, heterocyclic rings, alkylaryl groups, or aryl groups, or heteroaryl groups. Examples of the substituent that the 5-membered or 6-membered ring formed by linking two R ⁷ adjacent to each other, which can be included in the general formula (5), are listed as examples of R ⁷ Although a substituent is mentioned, it is not limited to these. The 5-membered ring or 6-membered ring may be linked to another porphyrin ring which may have a substituent. Examples of R ^{8 in} the general formula (5) include, but are not limited to, the substituents mentioned as examples of R ⁷ . Examples of the metal atom contained in the metal porphyrins and metal phthalocyanines include Pt, Pd, Ru, Rh, Ir, Zn, Cu and the like as the metal atom M in the general formula (5).

  Examples of the metalloporphyrins represented by the general formula (5) include meso-tetraphenyl-tetrabenzoporphyrin metal complexes such as meso-tetraphenyl-tetrabenzoporphyrin palladium (CAS number: 119654-64-7), Octaethylporphyrin metal complexes such as octaethylporphyrin palladium (CAS number: 24804-00-0); Baluschev, et al. , New Journal of Physics, vol. 10, p. Examples include octaethylporphyrin metal complexes such as meso-tetraphenyl-octamethoxy-tetranaphtho [2,3] porphyrin palladium described in 0130007-1 to 013007-12, 2008.

  As an example of the organic photosensitizer molecule (A) having an absorption maximum wavelength in the range of 500 to 700 nm and not containing a metal in its structure, specifically, the following general formula (1)

(In the above formula, R ^{1 to} R ⁵ each independently represents an arbitrary substituent containing a hydrogen atom, and each adjacent substituent (a pair of R ¹ and R ² , a pair of R ² and R ⁴ , R pair ¹ and R ^3, a pair of R ³ and R ⁴⁾ may form a 5- or 6-membered ring having an optional substituent containing a hydrogen atom each linked to each other, R ⁶ is A halogen atom, an optionally substituted alkyl group having 1 to 5 carbon atoms, or an optionally substituted alkoxyl group having 1 to 5 carbon atoms)
Compound represented by (boron dipyrromethene compound), C _70, and the like.

Examples of R ^{1 to} R ^{5 in} the general formula (1) include hydrogen atom, alkyl group, alkenyl group, alkynyl group, halogen atom, hydroxy group (hydroxyl group), alkylcarbonyloxy group, arylcarbonyloxy group, alkoxy Carbonyloxy group, aryloxycarbonyloxy group, carboxylate, alkylcarbonyl group, arylcarbonyl group, alkoxycarbonyl group, aminocarbonyl group, alkylaminocarbonyl group, dialkylaminocarbonyl group, alkylthiocarbonyl group, alkoxyl group, phosphate group Phosphonate group, phosphinate group, cyano group, amino group (including alkylamino group, dialkylamino group, arylamino group, diarylamino group, and alkylarylamino group), acylamino group (alkyl carbohydrate group) Amidino group, imino group, sulfhydryl group, alkylthio group, arylthio group, thiocarboxylic acid group, sulfate group, alkylsulfinyl group, sulfonate group, sulfamoyl group. Groups, sulfonamido groups, nitro groups, trifluoromethyl groups, cyano groups, azide groups, heterocycles, alkylaryl groups, or aryl groups, or heteroaryl groups, but are not limited thereto. Substituents (R ¹ and R ² pairs, R ² and R ⁴ pairs, R ¹ and R ³ pairs, R ³ and R ⁴ , which are adjacent to each other and may be included in the general formula (1). Examples of the substituent that the 5-membered ring or 6-membered ring formed by linking each other with each other include, but are not limited to, the substituents exemplified as examples of R ^{1 to} R ⁵ .

R ¹ and R ⁴ in the general formula (1) are a hydrogen atom, a halogen atom, an optionally substituted aliphatic hydrocarbon group having 1 to 4 carbon atoms, or an optionally substituted phenyl. Group, a phenoxy group which may have a substituent, a thienyl group which may have a substituent, a thienoxy group which may have a substituent, the following formula (2)

2-carboxyl ethenyl group represented by the following formula (3)

It is preferable that it is a 2-carboxyl-2-cyanoethenyl group represented by these, It is more preferable that it is a C1-C3 alkyl group which may have a substituent, An unsubstituted C1-C3 More preferred is an alkyl group, and most preferred is an unsubstituted methyl group.

R ² and R ³ in the general formula (1) are a hydrogen atom, a halogen atom, an optionally substituted aliphatic hydrocarbon group having 1 to 4 carbon atoms, or an optionally substituted phenyl. Group, a phenoxy group which may have a substituent, a thienyl group which may have a substituent, a thienoxy group which may have a substituent, a 2-carboxyl ethenyl group represented by the formula (2) Or a 2-carboxyl-2-cyanoethenyl group represented by the formula (3), which is a hydrogen atom, a bromine atom or an iodine atom (provided that at least one of R ² and R ³ is a bromine atom or It is more preferably an iodine atom, and further preferably a hydrogen atom or an iodine atom (provided that at least one of R ² and R ³ is an iodine atom).

R ⁵ in the general formula (1) is a hydrogen atom, a halogen atom, an optionally substituted aliphatic hydrocarbon group having 1 to 4 carbon atoms, an optionally substituted phenyl group, or a substituted group. A phenoxy group which may have a group, a thienyl group which may have a substituent, a thienoxy group which may have a substituent, a 2-carboxylethenyl group represented by the formula (2), or the above It is preferably a 2-carboxyl-2-cyanoethenyl group represented by the formula (3), more preferably a phenyl group which may have a substituent, and an unsubstituted or alkyl-substituted phenyl group. Is more preferable.

R ⁶ in the general formula (1) is a halogen atom, an optionally substituted alkyl group having 1 to 5 carbon atoms, or an optionally substituted alkoxyl group having 1 to 5 carbon atoms. However, it is preferably a fluorine atom.

The organic photosensitizing molecule (A) is preferably a metalloporphyrin represented by the general formula (5) or a compound represented by the general formula (1). The compound represented by the general formula (1) is more preferable, and in the compound represented by the general formula (1), R ^{1 to} R ⁵ in the general formula (1) each independently represents a hydrogen atom, a halogen atom, or a substituent. An optionally substituted aliphatic hydrocarbon group having 1 to 4 carbon atoms, a phenyl group which may have a substituent, a phenoxy group which may have a substituent, a thienyl group which may have a substituent, It is a compound which is a thienoxy group which may have a substituent, a 2-carboxyl ethenyl group represented by the formula (2), or a 2-carboxyl-2-cyanoethenyl group represented by the formula (3). More preferably, the following general formula (4)

(In the above formula, R ¹ and R ⁴ each independently represents an alkyl group having 1 to 3 carbon atoms which may have a substituent, and R ² and R ³ each independently represent a hydrogen atom, a bromine atom, or iodine. An atom, at least one of R ² and R ³ is a bromine atom or an iodine atom, and R ⁵ represents a phenyl group which may have a substituent)
Most preferably, it is a compound represented by these. Thereby, the optical wavelength conversion element which has still higher optical wavelength conversion efficiency is realizable.

  As the compound represented by the general formula (1), specifically, the following formula

(2-iodo-1,3,5,7-tetramethyl-8-phenyl-4,4-difluoroboradiazaindacene) (absorption maximum wavelength 510 nm) represented by the following formula:

(2,6-diiodo-1,3,5,7-tetramethyl-8-phenyl-4,4-difluoroborazadiadacene) (absorption maximum wavelength 529 nm), represented by the following formula

(Absorption maximum wavelength 629 nm) represented by the following formula

(Absorption maximum wavelength 539 nm) represented by the following formula

(Absorption maximum wavelength 557 nm) represented by the following formula

(Absorption maximum wavelength 576 nm) represented by the following formula

(Absorption maximum wavelengths 575 nm and 618 nm) represented by the following formula:

(Absorption maximum wavelength 532 nm) represented by the following formula

(Absorption maximum wavelength 526 nm) etc. are mentioned. These organic photosensitizer molecules (A) may be used alone or in combination of two or more.

  As an example of the organic photosensitizer molecule (A) having the longest absorption maximum wavelength in the range of 250 to 499 nm and not containing metal in the structure, the following general formula (6)

(In the formula, R ^{11 to} R ¹⁸ each independently represent an arbitrary substituent containing a hydrogen atom, and may be the same or different, and two adjacent R ^{11 to} R ¹⁸ are connected to each other to form hydrogen. A 5-membered or 6-membered ring having an arbitrary substituent containing an atom may be formed, and X is a thio group (—S—), a sulfinyl group (—S (═O) —), a sulfonyl group (—S (═O) ₂ —), a divalent group represented by —N (R ¹⁹ ) —, or a divalent group represented by —C (R ²⁰ ) (R ²¹ ) —, and R ^{19 to} R ²¹ Each independently represents an optional substituent containing a hydrogen atom)
The compound represented by these is mentioned. Here, the “arbitrary substituent containing a hydrogen atom” means a hydrogen atom or an arbitrary substituent other than a hydrogen atom.

Examples of R ^{11 to} R ^{18 in} the general formula (6) include a hydrogen atom, an alkyl group (for example, an alkyl group having 1 to 12 carbon atoms), an alkenyl group, an alkynyl group, a halogen atom, a hydroxy group (hydroxyl group), Alkylcarbonyloxy group, arylcarbonyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, carboxylate, alkylcarbonyl group, arylcarbonyl group, alkoxycarbonyl group, aminocarbonyl group, alkylaminocarbonyl group, dialkylaminocarbonyl group Alkylthiocarbonyl group, alkoxyl group, phosphate group, phosphonate group, phosphinate group, cyano group, amino group (including alkylamino group, dialkylamino group, arylamino group, diarylamino group, and alkylarylamino group) ), Acylamino groups (including alkylcarbonylamino groups, arylcarbonylamino groups, carbamoyl groups, and ureido groups), amidino groups, imino groups, sulfhydryl groups, alkylthio groups, arylthio groups, thiocarboxylic acid groups, sulfate groups, alkyl groups Examples include sulfinyl group, sulfonate group, sulfamoyl group, sulfonamido group, nitro group, trifluoromethyl group, cyano group, azido group, heterocyclic ring, alkylaryl group, aryl group, or heteroaryl group. It is not limited. Examples of R ^{19 to} R ²¹ include a hydrogen atom, an alkyl group (for example, an alkyl group having 1 to 12 carbon atoms), an alkenyl group, an alkynyl group, a heterocyclic group, an alkylaryl group, an aryl group, or a heteroaryl group. For example, but not limited to. Examples of the substituents which a 5-membered ring or a 6-membered ring formed by connecting two adjacent to each other among R ^{11 to} R ²¹ that may be included in the general formula (6) include R ¹¹ to substituents exemplified as examples of R ¹⁸ include, but are not limited to.

In the compound represented by the general formula (6), X is a thio group, and R ^{11 to} R ¹⁸ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group, or an aryl group. Or a heteroaryl group.

  In the compound represented by the general formula (6), when X is a thio group, that is, a thioxanthone, for example, in addition to unsubstituted thioxanthone (CAS number: 492-22-8), 2, Substituted thioxanthones such as 4-diethylthioxanthone (CAS number: 82799-44-8), 2-isopropylthioxanthone (CAS number: 5495-84-1) and 2-chlorothioxanthone (CAS number: 86-39-5) are listed. It is done.

  In the compound represented by the general formula (6), when X is a sulfinyl group, that is, a thioxanthone oxide, for example, in addition to unsubstituted thioxanthone oxide (CAS number: 7605-15-4), Examples thereof include substituted thioxanthones such as 3-methylthioxanthone oxide (CAS number: 654670-82-3) and thioxanthone oxide derivatives described in JP-A No. 58-120605.

  In the compound represented by the general formula (6), when X is a sulfonyl group, that is, a thioxanthone dioxide, for example, an unsubstituted thioxanthone dioxide (CAS number: 3166-15-2) In addition, substituted thioxanthones such as 2-methylthioxanthone dioxide (CAS number: 87548-99-0) and thioxanthone dioxide derivatives described in JP-A No. 58-120605 can be mentioned.

In the compound represented by the general formula (6), when X is a divalent group represented by —N (R ¹⁹ ) —, that is, an acridone, for example, an unsubstituted acridone (CAS number) : 578-95-0), N-methylacridone (CAS number: 719-54-0), N-methyl-2-iodoacridone (CAS number: 1493782-35-6), N-butyl- Examples thereof include substituted acridones such as 2-chloroacridone (CAS number: 128420-54-2) and acridone derivatives described in JP-A-8-67873.

In the compound represented by the general formula (6), when X is a divalent group represented by —C (R ²⁰ ) (R ²¹ ) —, that is, an anthrone, for example, unsubstituted In addition to anthrone (CAS number: 90-44-8), substituted anthrone such as 3-methylanthrone (CAS number: 69653-12-9) and benzanthrone (CAS number: 82-05-3) can be mentioned. These organic photosensitizer molecules (A) may be used alone or in combination of two or more.

  In this application, when a particular part is referred to as a “group”, the part may be substituted with one or more (up to the maximum possible) substituents, even if it is not itself substituted. Also means good. For example, “alkyl group” means a substituted or unsubstituted alkyl group. In addition, the substituent that can be used in the compound in the present invention may be any substituent.

Although the example of such a substituent is given to the following, there is no restriction | limiting in particular, It is not limited to these. Examples of such substituents include halogen atoms, alkyl groups (including cycloalkyl groups, bicycloalkyl groups, and tricycloalkyl groups), alkenyl groups (including cycloalkenyl groups and bicycloalkenyl groups), alkynyl groups, and aryl groups. Group, heterocyclic group (also referred to as heterocyclic group), cyano group, hydroxyl group, nitro group, carboxyl group, alkoxy group, aryloxy group, silyloxy group, heterocyclic oxy group, acyloxy group, carbamoyloxy group, Alkylsulfonylamino group or arylsulfonylamino group, mercapto group, alkylthio group, arylthio group, heterocyclic thio group, sulfamoyl group, sulfo group, alkylsulfinyl group or arylsulfinyl group, alkylsulfonyl group or arylsulfonyl group, acid Group, aryloxycarbonyl group, alkoxycarbonyl group, carbamoyl group, arylazo group or heterocyclic azo group, imide group, phosphino group, phosphinyl group, phosphinyloxy group, phosphinylamino group, phosphono group, phospho group, silyl group Group, hydrazino group, ureido group, boronic acid group (—B (OH) ₂ ), phosphato group (—OPO (OH) ₂ ), sulfato group (—OSO ₃ H), and other known substituents.

  More specifically, examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

  The alkyl group includes a linear, branched, or cyclic substituted or unsubstituted alkyl group. The alkyl group is an aliphatic alkyl group (preferably a substituted or unsubstituted aliphatic alkyl group having 1 to 30 carbon atoms such as methyl group, ethyl group, n-propyl group, isopropyl group, t-butyl group, n- Octyl group, eicosyl group, 2-chloroethyl group, 2-cyanoethyl group, 2-ethylhexyl group), cycloalkyl group (preferably a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, such as cyclohexyl group, cyclopentyl Group, 4-n-dodecylcyclohexyl group), bicycloalkyl group (preferably a substituted or unsubstituted bicycloalkyl group having 5 to 30 carbon atoms, that is, one hydrogen atom was removed from a bicycloalkane having 5 to 30 carbon atoms. A monovalent group, for example, a bicyclo [1,2,2] heptan-2-yl group, bicyclo [2 2,2] octane-3-yl group), is intended to encompass three or more ring structures often tricycloalkyl group. An alkyl group (for example, an alkyl group of an alkylthio group) in the substituents described below includes an alkenyl group and an alkynyl group in addition to the above-described alkyl group.

  The alkenyl group includes a linear, branched, or cyclic substituted or unsubstituted alkenyl group. The alkenyl group is an aliphatic alkenyl group (preferably a substituted or unsubstituted aliphatic alkenyl group having 2 to 30 carbon atoms, such as vinyl group, allyl group, prenyl group, geranyl group, oleyl group), cycloalkenyl group ( Preferably, it is a substituted or unsubstituted cycloalkenyl group having 3 to 30 carbon atoms, that is, a monovalent group obtained by removing one hydrogen atom of a cycloalkene having 3 to 30 carbon atoms, such as 2-cyclopentene-1- Yl group, 2-cyclohexen-1-yl group, etc.), bicycloalkenyl group (substituted or unsubstituted bicycloalkenyl group, that is, a monovalent group obtained by removing one hydrogen atom of a bicycloalkene having one double bond) Yes, preferably a substituted or unsubstituted bicycloalkenyl group having 5 to 30 carbon atoms, such as bicyclo [2,2, ] Hept-2-en-1-yl group, a bicyclo [2,2,2], etc. oct-2-en-4-yl group) is intended to encompass such. The alkynyl group is preferably a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, such as an ethynyl group, a propargyl group, or a trimethylsilylethynyl group.

  The aryl group is preferably a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, such as a phenyl group, a biphenyl group, a p-tolyl group, a naphthyl group, an m-chlorophenyl group, an o-hexadecanoylaminophenyl group, and the like. It is. The heterocyclic group is preferably a monovalent group obtained by removing one hydrogen atom from a 5- or 6-membered substituted or unsubstituted aromatic or non-aromatic heterocyclic compound, and more preferably, It is a 5- or 6-membered aromatic heterocyclic group having 3 to 30 carbon atoms. Examples of the heterocyclic group include a 2-furyl group, a 2-thienyl group, a 2-pyrimidinyl group, and a 2-benzothiazolyl group. The heterocyclic group may be a cationic heterocyclic group such as 1-methyl-2-pyridinio group or 1-methyl-2-quinolinio group.

  The alkoxy group is preferably a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, such as a methoxy group, an ethoxy group, an isopropoxy group, a t-butoxy group, an n-octyloxy group, or a 2-methoxyethoxy group. Etc. The aryloxy group is preferably a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, such as a phenoxy group, 2-methylphenoxy group, 4-t-butylphenoxy group, 3-nitrophenoxy group, 2 -Tetradecanoylaminophenoxy group and the like.

  The silyloxy group is preferably a silyloxy group having 3 to 20 carbon atoms, such as a trimethylsilyloxy group or a t-butyldimethylsilyloxy group. The heterocyclic oxy group is preferably a substituted or unsubstituted heterocyclic oxy group having 2 to 30 carbon atoms, such as a 1-phenyltetrazol-5-oxy group and a 2-tetrahydropyranyloxy group.

  The acyloxy group is preferably a formyloxy group, a substituted or unsubstituted alkylcarbonyloxy group having 2 to 30 carbon atoms, or a substituted or unsubstituted arylcarbonyloxy group having 6 to 30 carbon atoms, such as a formyloxy group. Acetyloxy group, pivaloyloxy group, stearoyloxy group, benzoyloxy group, p-methoxyphenylcarbonyloxy group and the like.

  The carbamoyloxy group is preferably a substituted or unsubstituted carbamoyloxy group having 1 to 30 carbon atoms, such as N, N-dimethylcarbamoyloxy group, N, N-diethylcarbamoyloxy group, morpholinocarbonyloxy group, N , N-di-n-octylaminocarbonyloxy group, Nn-octylcarbamoyloxy group, and the like.

  The alkylsulfonylamino group or arylsulfonylamino group is preferably a substituted or unsubstituted alkylsulfonylamino group having 1 to 30 carbon atoms, or a substituted or unsubstituted arylsulfonylamino group having 6 to 30 carbon atoms, such as methyl. A sulfonylamino group, a butylsulfonylamino group, a phenylsulfonylamino group, a 2,3,5-trichlorophenylsulfonylamino group, a p-methylphenylsulfonylamino group, and the like.

  The alkylthio group is preferably a substituted or unsubstituted alkylthio group having 1 to 30 carbon atoms, such as a methylthio group, an ethylthio group, or an n-hexadecylthio group. The arylthio group is preferably a substituted or unsubstituted arylthio group having 6 to 30 carbon atoms, such as a phenylthio group, a p-chlorophenylthio group, and an m-methoxyphenylthio group. The heterocyclic thio group is preferably a substituted or unsubstituted heterocyclic thio group having 2 to 30 carbon atoms, such as a 2-benzothiazolylthio group, a 1-phenyltetrazol-5-ylthio group, and the like.

  The sulfamoyl group is preferably a substituted or unsubstituted sulfamoyl group having 0 to 30 carbon atoms, such as N-ethylsulfamoyl group, N- (3-dodecyloxypropyl) sulfamoyl group, N, N-dimethylsulfa. A moyl group, an N-acetylsulfamoyl group, an N-benzoylsulfamoyl group, an N- (N′-phenylcarbamoyl) sulfamoyl group, and the like.

  The alkylsulfinyl group or arylsulfinyl group is preferably a substituted or unsubstituted alkylsulfinyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsulfinyl group having 6 to 30 carbon atoms, such as a methylsulfinyl group, ethyl A sulfinyl group, a phenylsulfinyl group, a p-methylphenylsulfinyl group, and the like. The alkylsulfonyl group or arylsulfonyl group is preferably a substituted or unsubstituted alkylsulfonyl group having 1 to 30 carbon atoms or a substituted or unsubstituted arylsulfonyl group having 6 to 30 carbon atoms, such as a methylsulfonyl group, ethyl A sulfonyl group, a phenylsulfonyl group, a p-methylphenylsulfonyl group, and the like.

  The acyl group is preferably a formyl group, a substituted or unsubstituted alkylcarbonyl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted group having 4 to 30 carbon atoms. Heterocyclic carbonyl groups bonded to carbonyl groups at substituted carbon atoms, for example, acetyl, pivaloyl, 2-chloroacetyl, stearoyl, benzoyl, pn-octyloxyphenylcarbonyl, 2-pyridyl A carbonyl group, a 2-furylcarbonyl group, and the like.

  The aryloxycarbonyl group is preferably a substituted or unsubstituted aryloxycarbonyl group having 7 to 30 carbon atoms such as phenoxycarbonyl group, o-chlorophenoxycarbonyl group, m-nitrophenoxycarbonyl group, pt- And a butylphenoxycarbonyl group. The alkoxycarbonyl group is preferably a substituted or unsubstituted alkoxycarbonyl group having 2 to 30 carbon atoms, such as a methoxycarbonyl group, an ethoxycarbonyl group, a t-butoxycarbonyl group, and an n-octadecyloxycarbonyl group.

  The carbamoyl group is preferably a substituted or unsubstituted carbamoyl group having 1 to 30 carbon atoms, such as carbamoyl group, N-methylcarbamoyl group, N, N-dimethylcarbamoyl group, N, N-di-n-octyl. A carbamoyl group, an N- (methylsulfonyl) carbamoyl group, and the like.

  The arylazo group or heterocyclic azo group is preferably a substituted or unsubstituted arylazo group having 6 to 30 carbon atoms or a substituted or unsubstituted heterocyclic azo group having 3 to 30 carbon atoms such as a phenylazo group and p-chlorophenyl. And an azo group and a 5-ethylthio-1,3,4-thiadiazol-2-ylazo group. The imide group is preferably an N-succinimide group, an N-phthalimide group, or the like.

  The phosphino group is preferably a substituted or unsubstituted phosphino group having 2 to 30 carbon atoms, such as a dimethylphosphino group, a diphenylphosphino group, a methylphenoxyphosphino group, and the like. The phosphinyl group is preferably a substituted or unsubstituted phosphinyl group having 2 to 30 carbon atoms, such as a phosphinyl group, a dioctyloxyphosphinyl group, a diethoxyphosphinyl group, and the like.

  The phosphinyloxy group is preferably a substituted or unsubstituted phosphinyloxy group having 2 to 30 carbon atoms, such as a diphenoxyphosphinyloxy group or a dioctyloxyphosphinyloxy group. The phosphinylamino group is preferably a substituted or unsubstituted phosphinylamino group having 2 to 30 carbon atoms, such as a dimethoxyphosphinylamino group or a dimethylaminophosphinylamino group.

  The silyl group is preferably a substituted or unsubstituted silyl group having 3 to 30 carbon atoms, such as a trimethylsilyl group, a t-butyldimethylsilyl group, or a phenyldimethylsilyl group.

  The hydrazino group is preferably a substituted or unsubstituted hydrazino group having 0 to 30 carbon atoms, such as a trimethylhydrazino group. The ureido group is preferably a substituted or unsubstituted ureido group having 0 to 30 carbon atoms, such as an N, N-dimethylureido group.

  These substituents include those in which two substituents jointly form a ring. The ring is an aromatic or non-aromatic hydrocarbon ring or heterocyclic ring. These rings can be further combined to form a polycyclic fused ring. Examples of the ring include a benzene ring, naphthalene ring, anthracene ring, phenanthrene ring, fluorene ring, triphenylene ring, naphthacene ring, biphenyl ring, pyrrole ring, furan ring, thiophene ring, imidazole ring, oxazole ring, thiazole ring, pyridine. Ring, pyrazine ring, pyrimidine ring, pyridazine ring, indolizine ring, indole ring, benzofuran ring, benzothiophene ring, isobenzofuran ring, quinolidine ring, quinoline ring, phthalazine ring, naphthyridine ring, quinoxaline ring, quinoxazoline ring, isoquinoline ring, Examples thereof include a carbazole ring, a phenanthridine ring, an acridine ring, a phenanthroline ring, a thianthrene ring, a chromene ring, a xanthene ring, a phenoxathiin ring, a phenothiazine ring, and a phenazine ring.

  Among the above substituents, those having a hydrogen atom may be removed and further substituted with the above substituents. Examples of such substituents include halogen atoms, alkyl groups (including cycloalkyl groups, bicycloalkyl groups, and tricycloalkyl groups), alkenyl groups (including cycloalkenyl groups and bicycloalkenyl groups), and alkynyl groups described above. Group, aryl group, heterocyclic group, cyano group, hydroxyl group, nitro group and the like.

  The organic light-emitting molecule (B) is not particularly limited as long as it is an organic compound that can be used together with the organic photosensitizer molecule (A) to emit light up-converted by the TTA process. Can be used. Examples of the organic light emitting molecule (B) include acenaphthene derivatives, acetophenone derivatives, anthracene derivatives, diphenylacetylene derivatives, acridan derivatives, acridine derivatives, acridone derivatives, thioacridone derivatives, angelicin derivatives, anthracene derivatives, anthraquinone derivatives, azafluorene derivatives, Azulene derivatives, benzyl derivatives, carbazole derivatives, coronene derivatives, sumanene derivatives, biphenylene derivatives, fluorene derivatives, perylene derivatives, phenanthrene derivatives, phenanthroline derivatives, phenazine derivatives, benzophenone derivatives, pyrene derivatives, benzoquinone derivatives, biacetyl derivatives, bianthranyl derivatives, fullerenes Derivatives, graphene derivatives, carotene derivatives, chlorophyll derivatives, chrysanthemum Derivatives, cinnoline derivatives, coumarin derivatives, curcumin derivatives, dansylamide derivatives, flavone derivatives, fluorenone derivatives, fluorescein derivatives, helicene derivatives, indene derivatives, lumichrome derivatives, lumiflavin derivatives, oxadiazole derivatives, oxazole derivatives, perifuranthene derivatives, perylene derivatives, Phenanthrene derivatives, phenanthroline derivatives, phenazine derivatives, phenol derivatives, phenothiazine derivatives, phenoxazine derivatives, phthalazine derivatives, phthalocyanine derivatives, picene derivatives, porphyrin derivatives, porphycene derivatives, hemiporphycene derivatives, subphthalocyanine derivatives, psoralen derivatives, angelicin derivatives, purine derivatives , Pyrene derivatives, pyromethene derivatives, pyridyl ketone derivatives , Phenyl ketone derivative, pyridyl ketone derivative, thienyl ketone derivative, furanyl ketone derivative, quinazoline derivative, quinoline derivative, quinoxaline derivative, retinal derivative, retinol derivative, rhodamine derivative, riboflavin derivative, rubrene derivative, squalene derivative, stilbene derivative, tetracene derivative, pentacene Derivatives, anthraquinone derivatives, tetracenequinone derivatives, pentacenequinone derivatives, thiophosgene derivatives, indigo derivatives, thioinzogo derivatives, thioxanthene derivatives, thymine derivatives, triphenylene derivatives, triphenylmethane derivatives, triaryl derivatives, tryptophan derivatives, uracil derivatives, xanthene derivatives, Ferrocene derivatives, azulene derivatives, biacetyl derivatives, terphenyl derivatives, -Furan derivatives, terthiophene derivatives, oligoaryl derivatives, fullerene derivatives, conjugated polyene derivatives, group 14 element condensed polycyclic aromatic compound derivatives, condensed polycyclic heteroaromatic compound derivatives, etc. is not.

  Specific examples of the organic light emitting molecule (B) include 9,10-diphenylanthracene (CAS number: 1499-10-1) and derivatives thereof, and 9,10-bis (phenylethynyl) anthracene (CAS number). : 10075-85-1) and derivatives thereof (eg 1-chloro-9,10-bis (phenylethynyl) anthracene), perylene (CAS number: 198-55-0) and derivatives thereof (eg perylene diimide), pyrene and Derivatives thereof, rubrene and derivatives thereof, naphthalene and derivatives thereof (eg 1-dodecylnaphthalene, naphthalene diimide, perfluoronaphthalene, 1-cyanonaphthalene, 1-methoxynaphthalene, 2-cyanonaphthalene, 2-methoxynaphthalene, 1-methyl Naphthalene, acenaphthe ), 9,10-bis (phenylethynyl) naphthacene, 4,4′-bis (5-tetraaceenyl) -1,1′-biphenylene, indole, benzofuran, benzothiophene, biphenyl and its derivatives, bifuran, bithiophene, 4, Examples include 4-difluoro-4-bora-3a, 4a-diaza-s-indacene (boron dipyrromethene), but are not limited thereto. As the organic light emitting molecule (B), condensed polycyclic aromatic compounds such as perylene, pyrene, naphthalene and derivatives thereof, particularly aromatic π electron conjugated compounds are preferable.

  As an example of a preferable compound of the organic light emitting molecule (B), the following general formula (7)

(Wherein, divalent Z is the -C (R ²⁸⁾ = represented by ^{Y-, -N (R 30) -} 2 divalent group represented by an oxy group (-O-), or a thio group Y represents a trivalent group represented by ═C (R ²⁹ ) — or an aza group (═N—), and R ^{22 to} R ³⁰ each independently represents an arbitrary substituent containing a hydrogen atom. May be the same or different, and two of R ^{22 to} R ³⁰ that are adjacent to each other may be linked to each other to form a 5-membered or 6-membered ring having an arbitrary substituent containing a hydrogen atom)
The compound represented by these is mentioned. In the compound represented by the general formula (7), R ^{22 to} R ²⁹ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group, an aryl group, or a heteroaryl group. In the general formula (2), R ³⁰ is preferably a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, a heterocyclic group, an alkylaryl group, an aryl group, or a heteroaryl group.

Among the compounds represented by the general formula (7), when Z is a divalent group represented by —C (R ²⁸ ) ═Y—, that is, the following general formula (8)

(In the formula, Y represents a trivalent group represented by ═C (R ²⁹ ) — or an aza group, and R ^{22 to} R ²⁹ each independently represents an arbitrary substituent containing a hydrogen atom. And two adjacent ones of R ^{22 to} R ²⁹ may be linked to each other to form a 5-membered or 6-membered ring having an arbitrary substituent containing a hydrogen atom)
The compound represented by these is preferable.

Of the compounds represented by the general formula (8), when Y is a trivalent group represented by ═C (R ²⁹ ) —, that is, the following general formula (9)

(In the formula, R ^{22 to} R ²⁹ each independently represent an arbitrary substituent containing a hydrogen atom, and may be the same or different, and two adjacent R ^{22 to} R ²⁹ are connected to each other to form hydrogen. A 5-membered ring or a 6-membered ring having an arbitrary substituent containing an atom may be formed)
The compound represented by these is preferable. Furthermore, in the compound represented by the general formula (9), R ^{22 to} R ²⁹ are each independently a hydrogen atom, a halogen atom, an alkyl group, an alkoxy group, a cyano group, a nitro group, an aryl group, or a heteroaryl group. It is preferable that

  As another example of a preferable compound of the organic light emitting molecule (B), the following general formula (10)

(In the formula, R ^{31 to} R ³⁶ each independently represents an arbitrary substituent containing a hydrogen atom, and may be the same or different, and two of R ^{31 to} R ³⁶ adjacent to each other are connected to each other to form hydrogen. A 5-membered ring or a 6-membered ring having an arbitrary substituent containing an atom may be formed, Q represents a divalent group represented by —N (R ³⁷ ) —, an oxy group, or a thio group, and R Represents a divalent group represented by —N (R ³⁸ ) —, an oxy group, or a thio group)
The compound represented by these is mentioned.

  As another example of a preferable compound of the organic light emitting molecule (B), the following general formula (11)

(In the formula, R ^{43 to} R ⁵² each independently represents an arbitrary substituent containing a hydrogen atom and may be the same or different, and two of R ^{43 to} R ⁵² adjacent to each other are connected to each other to form a hydrogen atom. A 5-membered or 6-membered ring having an arbitrary substituent containing an atom may be formed, and R ⁴³ and R ⁵² are connected to each other to form an optional substituent containing a hydrogen atom. A ring may be formed, and R ⁴⁷ and R ⁴⁸ may be linked to each other to form a 5-membered or 6-membered ring having an arbitrary substituent containing a hydrogen atom)
The compound represented by these is mentioned.

  Here, the “arbitrary substituent containing a hydrogen atom” means a hydrogen atom or an arbitrary substituent other than a hydrogen atom.

Examples of R ^{22 to} R ²⁷ , R ^{31 to} R ³⁶ , and R ^{43 to} R ^{52 in} the general formulas (8) to (11) include a hydrogen atom and an alkyl group (for example, an alkyl group having 1 to 12 carbon atoms). ), Alkenyl group, alkynyl group, halogen atom, hydroxy group (hydroxyl group), alkylcarbonyloxy group, arylcarbonyloxy group, alkoxycarbonyloxy group, aryloxycarbonyloxy group, carboxylate, alkylcarbonyl group, arylcarbonyl group, Alkoxycarbonyl group, aminocarbonyl group, alkylaminocarbonyl group, dialkylaminocarbonyl group, alkylthiocarbonyl group, alkoxyl group, phosphate group, phosphonate group, phosphinate group, cyano group, amino group (alkylamino group, dialkylamino group , Arylamino group, diaryl Mino group and alkylarylamino group), acylamino group (including alkylcarbonylamino group, arylcarbonylamino group, carbamoyl group, and ureido group), amidino group, imino group, sulfhydryl group, alkylthio group, arylthio group Thiocarboxylate group, sulfate group, alkylsulfinyl group, sulfonate group, sulfamoyl group, sulfonamide group, nitro group, trifluoromethyl group, cyano group, azide group, heterocycle, alkylaryl group, aryl group, or hetero Examples include, but are not limited to, aryl groups. Examples of R ³⁰ , R ³⁷ and R ³⁸ include a hydrogen atom, an alkyl group (eg, an alkyl group having 1 to 12 carbon atoms), an alkenyl group, an alkynyl group, a heterocyclic group, an alkylaryl group, an aryl group, or a hetero group Examples include, but are not limited to, aryl groups. Among R ^{22 to} R ³⁸ and R ^{43 to} R ⁵² that may be included in the general formulas (8) to (11), a two-membered ring formed by connecting two adjacent to each other has a 5-membered ring or a 6-membered ring. A substituent, an arbitrary substituent containing a hydrogen atom in a 5-membered or 6-membered ring formed by connecting R ⁴³ and R ⁵² to each other, and R ⁴⁷ and R ⁴⁸ connected to each other; Examples of the optional substituent containing a hydrogen atom contained in a 5-membered ring or 6-membered ring include the substituents exemplified as examples of R ^{22 to} R ²⁷ , R ^{31 to} R ³⁶ , and R ^{43 to} R ^52. However, it is not limited to these.

In the compound represented by the general formula (8), when Y is a trivalent group represented by ═C (R ²⁹ ) —, that is, naphthalene, for example, unsubstituted naphthalene (CAS number) : 91-20-3), octafluoronaphthalene (CAS number: 313-72-4), 2-methoxynaphthalene (CAS number: 93-04-9) and 2-cyanonaphthalene (CAS number: 613-46). -7), 1-dodecylnaphthalene (CAS number: 38641-16-6), 1-methylnaphthalene (CAS number: 90-12-0), acenaphthene (CAS number: 83-32-9), 2,6- Examples thereof include substituted naphthalene such as di-tert-butylnaphthalene 2,6-di-tert-butylnaphthalene (CAS number: 3905-64-4).

  In the compound represented by the general formula (8), when Y is an aza group, that is, a quinoline, for example, in addition to unsubstituted quinoline (CAS number: 91-22-5), 6- Examples thereof include substituted naphthalenes such as tertiary butyl quinoline (CAS number: 68141-13-9) and benzo [h] quinoline (CAS number: 230-27-3).

In the compound represented by the general formula (7), when Z is a divalent group represented by —N (R ²⁰ ) —, that is, an indole, for example, an unsubstituted indole (CAS number) : 120-72-9), and substituted indoles such as 1,2-dimethylindole (CAS number: 875-79-6) and naphthostyryl (CAS number: 130-00-7).

  In the compound represented by the general formula (7), when Z is an oxy group, that is, a benzofuran, for example, in addition to unsubstituted benzofuran (CAS number: 271-89-6), 2- Examples thereof include substituted benzofurans such as butylbenzofuran (CAS number: 4265-27-4) and diphenylene oxide (CAS number: 132-64-9).

  In the compound represented by the general formula (7), when Z is a thio group, that is, a benzothiophene, for example, in addition to unsubstituted benzothiophene (CAS number: 95-15-8), Examples thereof include substituted benzofurans such as 2-methylbenzothiophene (CAS number: 1195-14-8) and dibenzothiophene (CAS number: 132-65-0).

In the compound represented by the general formula (10), Q is a divalent group represented by —N (R ³⁷ ) —, and R is a divalent group represented by —N (R ³⁸ ) —. That is, in the case of bipyrroles, for example, in addition to unsubstituted bipyrrole (CAS number: 10090-64-6), 5,5′-dimethyl-bipyrrole (CAS number: 90888-56-5) and 1, Examples thereof include substituted bipyrroles such as 1′-dimethyl-bipyrrole (CAS number: 34671-26-6).

In the general formula (10), when Q is a divalent group represented by —N (R ³⁷ ) — and R is an oxy group, that is, furanylpyrroles, for example, an unsubstituted group In addition to furanylpyrrole (CAS number: 63122-43-0), such as 1-methyl-furanylpyrrole (CAS number: 124494-77-5) and benzofuranylindole (CAS number: 78842-63-4) Substituted furanyl pyrrole. In the compound represented by the general formula (10), when Q is an oxy group and R is a divalent group represented by —N (R ³⁸ ) —, the same example can be given.

In the compound represented by the general formula (10), when Q is a divalent group represented by —N (R ³⁷ ) — and R is a thio group, that is, a thienylpyrrole, In addition to unsubstituted thienylpyrrole (CAS number: 52707-46-7), 1-methyl-thienylpyrrole (CAS number: 34671-27-7), thienyl dol (CAS number: 55968-16-6), etc. Substituted thienylpyrrole is mentioned. In the compound represented by the general formula (10), when Q is a thio group and R is a divalent group represented by —N (R ³⁸ ) —, the same example can be given.

  In the compound represented by the general formula (10), when Q is an oxy group and R is an oxy group, that is, bifurans, for example, unsubstituted bifuran (CAS number: 5905-00- In addition to 0), substituted bifurans such as 5,5′-dimethyl-bifuran (CAS number: 17490-66-3) and 5,5′-dicyano-bifuran (CAS number: 261719-71-5) can be mentioned.

  In the compound represented by the general formula (10), when Q is an oxy group and R is a thio group, that is, a thienylfuran, for example, an unsubstituted thienylfuran (CAS number: 27521- 80-8) and substituted thienylfurans such as 2-methyl-thienylfuran (CAS number: 125261-84-9) and thienylfurancarbaldehyde (CAS number: 32364-30-0). In the compound represented by the general formula (10), when Q is a thio group and R is an oxy group, the same example can be given.

  In the compound represented by the general formula (10), when Q is a thio group and R is a thio group, that is, bithiophenes, for example, unsubstituted bithiophene (CAS number: 492-97- In addition to 7), substituted bithiophenes such as 5,5′-dimethyl-bithiophene (CAS number: 16303-58-5) and bithiophene-dimethanol (CAS number: 170110-96-0) can be mentioned.

  Examples of the compound represented by the general formula (11) include substitution of p-terphenyl (CAS number: 92-94-4) and the like in addition to unsubstituted biphenyl (CAS number: 92-52-4). Biphenyl is mentioned. These organic light emitting molecules (B) may be used alone or in combination of two or more.

  The organic photosensitizer molecule (A) and the organic light emitting molecule (B) can be freely selected from the above examples and can be used in any combination. However, in order to emit light up-converted light by the TTA process. It is preferable from the viewpoint of the efficiency of triplet-triplet energy transfer that the energy levels of the lowest triplet excited state of the organic photosensitizer molecule (A) and the organic light emitting molecule (B) are close. Therefore, the following formula

( _Where E _{T, Dye} is the energy level of the lowest triplet excited state of the organic photosensitizer molecule (A), and E _{T, Emi} is the energy level of the lowest triplet excited state of the organic light emitting molecule (B)). )
ΔE _T is preferably −0.5 eV or more and 2.0 eV or less, and more preferably −0 to 0.0 eV for any combination of the organic photosensitizer molecule (A) and the organic light emitting molecule (B). It is 3 eV or more and 1.0 eV or less, More preferably, it is -0.2 eV or more and 0.5 eV or less, Especially preferably, it is -0.1 eV or more and 0.3 eV or less. 1 eV is energy that an electron obtains when one electron is accelerated by a potential difference of 1 V.

  The contents of the organic photosensitizer molecule (A) and the organic light emitting molecule (B) in the light wavelength conversion element of the present invention are not particularly limited, but the organic photosensitizer molecule (A) in the light wavelength conversion element, When the total of the organic light emitting molecule (B) and the deep eutectic solvent (C) is 100 parts by mass, it is usually 0.000001 to 10 parts by mass, preferably 0.00001 to 5 parts by mass. More preferably, it is 0.0001-1 mass part.

  The deep eutectic solvent (C) may be a mixture of a salt and a hydrogen bond donor and having a melting point greatly lowered by the eutectic, and is liquid at room temperature (25 ° C.). May be solid at room temperature (25 ° C.), but is a mixture of a solid salt at room temperature (25 ° C.) and a hydrogen bond donor that is solid or liquid at room temperature (25 ° C.) at room temperature (25 ° C. A liquid mixture is preferred. As the salt constituting the deep eutectic solvent (C), a halogen salt can be used, and the halogen salt is preferably a nonmetallic halogen salt. When the salt constituting the deep eutectic solvent (C) is a non-metallic halogen salt, the deep eutectic solvent (C) does not contain a metal, so it is environmentally friendly and used for ordinary applications. Easy to do. As the deep eutectic solvent (C), the deep eutectic solvent (C) is a non-metallic halogen salt that is solid at room temperature (25 ° C.) and a hydrogen bond donor that is solid or liquid at room temperature (25 ° C.). It is particularly preferable that the mixture is a liquid mixture at room temperature (25 ° C.). Furthermore, the deep eutectic solvent (C) used in the light wavelength conversion element of the present invention is preferably a liquid mixture having high optical transparency and at room temperature (25 ° C.).

  Examples of the metal halogen salt include zinc chloride. Although it does not specifically limit as said nonmetallic halogen salt, For example, a quaternary ammonium halide, a quaternary phosphonium halide, a tertiary ammonium halide, a primary ammonium halide etc. are mentioned.

  The quaternary ammonium halide is not particularly limited, and examples thereof include choline chloride, tetrabutylammonium chloride, tetramethylammonium chloride, acetylcholine chloride, chlorocholine chloride, tetraethylammonium bromide, N- (2-hydroxyethyl)- Examples thereof include N, N-dimethylbenzenemethanaminium chloride, fluorocholine bromide, and tetrabutylammonium bromide.

  Examples of the quaternary phosphonium halide include methyltriphenylphosphonium bromide and benzyltriphenylphosphonium chloride. Examples of the tertiary ammonium halide include 2- (diethylamino) ethanol hydrochloride. Examples of the primary ammonium halide include ethylamine hydrochloride.

  The hydrogen bond donor is not particularly limited. For example, ethylene glycol, glycerin, lactic acid, tartaric acid, glucose, sucrose, xylose, ascorbic acid, citric acid, urea, thiourea, 1-methylurea, 1,3- Dimethylurea, 1,1-dimethylurea, acetamide, benzamide, 2,2,2-trifluoroacetamide, imidazole, adipic acid, benzoic acid, malonic acid, oxalic acid, phenylacetic acid, 3-phenylpropionic acid, succinic acid, 1,2,3-propanetricarboxylic acid, levulinic acid, itaconic acid, xylitol, D-sorbitol, D-isosorbide, 4-hydroxybenzoic acid, caffeic acid, p-coumaric acid, trans-cinnamic acid, suberic acid, gallic acid Acid, resorcinol, hexanediol, 1,4-butanediol And triethylene glycol.

  Content of the said deep eutectic solvent (C) is 10 mass parts or more normally with respect to 100 mass parts of light wavelength conversion elements, Preferably it is 30 mass parts or more.

  The light wavelength conversion element of the present invention is obtained by dissolving and / or dispersing the organic photosensitizer molecule (A) and the organic light emitting molecule (B) in the deep eutectic solvent (C) using a generally known technique. It can be produced by a method for obtaining a dispersion. In the above method, if necessary, other additives are mixed with the organic photosensitizer molecule (A) and the organic light emitting molecule (B) in a deep eutectic solvent (C) using a generally known technique, A solution or dispersion may be obtained. Further, in the above method, a known disperser such as an ultrasonic disperser, a bead mill, a homogenizer, a wet jet mill, a ball mill, an attritor, a sand mill, a roll mill, and a microwave disperser may be used alone or in combination. The organic photosensitizing molecule (A) and the organic light emitting molecule (B) may be finely pulverized and finely dispersed to obtain a solution or dispersion.

  As another method for producing the light wavelength conversion element of the present invention, for example, first, the organic photosensitizer molecule (A) and the organic light emitting molecule (B) are dissolved and / or dispersed in a volatile organic solvent, Next, the obtained solution and / or dispersion is stirred and mixed with the deep eutectic solvent (C) to produce a visually homogeneous and transparent solution and / or dispersion, and further from the solution and / or dispersion. A method of removing the volatile organic solvent to a trace amount or less under reduced pressure can also be used. This method makes it easy to obtain a light wavelength conversion element that is homogeneously and transparently mixed, and a light wavelength conversion element having high stability and high light wavelength conversion efficiency can be obtained. Therefore, the light wavelength conversion element of the present invention is obtained. More preferable as a method.

  The volatile organic solvent used in the above method can dissolve and / or disperse the organic photosensitizer molecule (A) and the organic light emitting molecule (B), and is homogeneously and transparently mixed with the deep eutectic solvent (C). The organic solvent is not particularly limited as long as it is volatile and can be removed to a trace amount under reduced pressure. Here, the “trace amount” is an amount that can detect the volatile organic solvent mixed in the deep eutectic solvent (C) only at a noise level or less based on the measurement of the light absorption spectrum. The volatile organic solvent is preferably a volatile organic solvent that can dissolve the organic photosensitizing molecule (A) and the organic light emitting molecule (B). As the volatile organic solvent, aromatic solvents such as toluene, benzene and xylene can be used. When a volatile organic solvent capable of dissolving the organic photosensitizing molecule (A) and the organic light emitting molecule (B) is used, the volatile organic solvent matches the solubility of the organic photosensitizing molecule and the organic light emitting molecule. Can be selected as appropriate.

  As the stirring and mixing means, known techniques or apparatuses such as ultrasonic waves, bubbling, agitators, liquid feed pumps, pulverizers, bead mills, homogenizers, wet jet mills, and microwaves can be used. These means may be used alone or in combination of two or more.

  Furthermore, in the light wavelength conversion element of the present invention, if necessary, as a component other than the organic photosensitizer molecule (A), the organic light emitting molecule (B), and the deep eutectic solvent (C), convenience during handling, etc. In order to improve the above, various additives such as an antifoaming agent, a leveling agent, a light stabilizer, an antioxidant, a polymerization inhibitor, an antistatic agent, and an ultraviolet absorber can be added.

  The light wavelength conversion element of the present invention preferably has a moisture content of 1% by mass or less, more preferably 0.1% by mass or less, and further preferably 0.01% by mass or less. Most preferably, it is 0.001 mass% or less. Thereby, the optical wavelength conversion element which has higher optical wavelength conversion efficiency is realizable.

  The light wavelength conversion element of the present invention preferably has an oxygen concentration of 100 ppm by mass or less, more preferably 10 ppm by mass or less, still more preferably 1 ppm by mass or less. Most preferably, it is 1 mass ppm or less. Thereby, the optical wavelength conversion element which has higher optical wavelength conversion efficiency is realizable.

  The light wavelength conversion element of the present invention can be used for solar cells, photocatalysts, photocatalytic hydrogen / oxygen generators, optical up-conversion filters, and the like.

  The solar cell of the present invention uses the light wavelength conversion element of the present invention.

  An example of the solar cell of the present invention will be described with reference to FIG. As shown in FIG. 1, a solar cell according to an example of the present invention includes a photoelectric conversion layer (solar cell layer) 1 and a strip-shaped light receiving surface electrode disposed on a light incident side surface of the photoelectric conversion layer 1. 7, a transparent back electrode 2 laminated on the back surface of the light incident side of the photoelectric conversion layer 1, a transparent insulating film 3 laminated on the back surface of the light incident side of the transparent back electrode 2, and transparent The up-conversion layer 4 using the light wavelength conversion element of the present invention laminated on the back surface of the light incident side surface of the insulating film 3 and the back conversion surface of the up-conversion layer 4 on the light incident side surface. And a light reflecting film 5.

  The photoelectric conversion layer 1 is not particularly limited, and an organic photoelectric conversion layer such as a dye-sensitized solar cell or an organic thin film solar cell, a compound semiconductor photoelectric conversion layer, a silicon photoelectric conversion layer, or the like is used. it can.

The light-receiving surface electrode 7 and the light reflection film 5 can be formed of a metal such as Ag, Al, Ti, Cr, Mo, W, Ni, or Cu. The transparent back electrode 2 can be formed of a transparent conductor such as ITO (indium tin oxide), SnO ₂ , or ZnO. The transparent insulating film 3 can be formed of a resin such as polyethylene terephthalate, polycarbonate, polyimide resin, acrylic resin, and polyether nitrile.

  The up-conversion layer 4 may be formed of a cell and an optical wavelength conversion element enclosed in the cell, as in the optical up-conversion filter of the present invention described later, and is formed only of the optical wavelength conversion element. May be. When the up-conversion layer 4 is formed only by the light wavelength conversion element, the transparent insulating film 3, the up-conversion layer 4, and the light reflection film 5 are sealed with a sealing member such as a sealing resin at the periphery thereof. Good.

  In the configuration of FIG. 1, the up-conversion layer 4 up-converts incident light 6 from the sun, particularly when the organic photosensitizer molecule (A) has an absorption maximum wavelength in the range of 500 to 700 nm. By converting into light having a short wavelength, the intensity of light in a wavelength range that can be used for power generation by the photoelectric conversion layer 1 can be increased, and the power generation efficiency of the solar cell can be further increased.

  In the configuration of FIG. 1, the up-conversion layer 4 is disposed between the transparent insulating film 3 and the light reflecting film 5, but the arrangement position of the up-conversion layer 4 is arranged on the light incident side of the light receiving surface electrode 7 or the like. You may change into other arrangement positions like. In that case, a transparent insulating film may be provided between the up-conversion layer 4 and the light-receiving surface electrode 7.

  In the solar cell of FIG. 1, the light receiving surface electrode 7 may be replaced with a transparent electrode formed on the entire light incident side surface of the photoelectric conversion layer 1. Further, in the solar cell of FIG. 1, the transparent insulating film 3 may be omitted. However, in the case where the up-conversion layer 4 is formed only of the light wavelength conversion element, the transparent insulating film 3 is replaced with the light wavelength conversion element and the transparent back electrode in order to avoid contact between the light wavelength conversion element and the transparent back electrode 2. 2 is preferable. Further, in the solar cell of FIG. 1, when the arrangement position of the upconversion layer 4 is changed to the light incident side in the light receiving surface electrode 7 and the transparent insulating film 3 is omitted, the transparent back electrode 2 is used as a light reflecting electrode. Alternatively, the light reflecting film 5 may be omitted.

  The photocatalyst of the present invention uses the light wavelength conversion element of the present invention. For example, a photocatalyst can be realized by arranging a photocatalyst layer instead of the light receiving surface electrode 7, the photoelectric conversion layer 1, the transparent back electrode 2, and the transparent insulating film 3 in the solar cell of FIG.

  As shown in FIG. 2, the photocatalyst according to an example of the present invention contains a glass channel in which water 10 (photocatalyst layer) to which a photocatalyst is added is accommodated and gas 9 is filled in a space other than the water 10 to which the photocatalyst is added. 8, the upconversion layer 4 formed on the side surface and the bottom surface of the glass channel 8, the light reflecting film 5 formed on the outer surface of the upconversion layer 4, and the light reflecting film 5 And a mechanical support 11 formed on the outer surface of the light reflecting film 5.

  In the configuration of FIG. 2, the up-conversion layer 4 up-converts the incident light 6 from the sun, particularly when the organic photosensitizer molecule (A) has an absorption maximum wavelength in the range of 500 to 700 nm. By converting to light having a shorter wavelength, the photocatalyst added to the water 10 can increase the intensity of light in a wavelength range that can be used for the catalytic reaction, and can further increase the conversion efficiency of the photocatalyst.

  The photocatalytic hydrogen / oxygen generator of the present invention uses the light wavelength conversion element of the present invention. For example, a photocatalytic hydrogen / oxygen generator is realized by disposing a photocatalyst layer in place of the light-receiving surface electrode 7, the photoelectric conversion layer 1, the transparent back electrode 2, and the transparent insulating film 3 in the solar cell of FIG. be able to.

  The optical up-conversion filter of the present invention is an optical up-conversion filter that converts light into light having a shorter wavelength, and includes the optical wavelength conversion element and a cell, and the optical wavelength conversion element is in the cell. Is enclosed.

  The cell is not particularly limited as long as it is a cell that can transmit light. For example, two glass plates made of quartz glass, borosilicate glass, etc. are overlapped and their peripheral portions are fused. A cell having a bonded structure can be used.

  The light wavelength conversion element is preferably enclosed in the cell with an oxygen concentration of 100 mass ppm or less, more preferably encapsulated in the cell in a state of 10 mass ppm or less. More preferably, it is enclosed in the cell in a state of 1 mass ppm or less, and most preferably, it is enclosed in the cell in a state of 0.1 mass ppm or less.

  The optical up-conversion filter is obtained by, for example, injecting a light wavelength conversion element into a cell, performing deoxygenation treatment until the oxygen concentration becomes 100 mass ppm or less as necessary, and then sealing the cell. Can be obtained. The deoxygenation method includes, for example, a method in which a light wavelength conversion element is decompressed using a vacuum pump such as a rotary pump or a turbo molecular pump, and an inert gas such as nitrogen gas or argon gas is used in the light wavelength conversion element. And a method in which the light wavelength conversion element is frozen and then decompressed (vacuum degassing) using a vacuum pump (freezing vacuum degassing method).

  The optical upconversion filter can be used as the upconversion layer 4 of the solar cell, photocatalyst, or photocatalytic hydrogen / oxygen generator.

  In addition, in articles such as solar cells, photocatalysts, photocatalytic hydrogen / oxygen generators, and optical up-conversion filters using the light wavelength conversion element of the present invention, an oxygen getter is used to reduce the oxygen concentration of the light wavelength conversion element. You may coexist. In addition, in articles such as solar cells, photocatalysts, photocatalytic hydrogen / oxygen generators, and optical up-conversion filters using the light wavelength conversion element of the present invention, a water absorbing material is used to reduce the oxygen concentration of the light wavelength conversion element. May coexist.

  Next, the present invention will be described in more detail with reference to examples. In addition, this invention is not limited at all by the following examples.

[Deep eutectic solvent used in Examples]
In the following Examples, as a deep eutectic solvent, a mixture of choline chloride (hereinafter abbreviated as “ChCl”) and glycerin (hereinafter abbreviated as “G”) in a molar ratio ChCl: G = 1: 2 ( Reference; hereinafter referred to as “deep eutectic solvent ChCl-G2”), mixture of ChCl and ethylene glycol (hereinafter abbreviated as “EG”) in a molar ratio ChCl: EG = 1: 2 (Non-patent Document 1) Reference; hereinafter referred to as “deep eutectic solvent ChCl-EG2”), tetrabutylammonium chloride (hereinafter abbreviated as “TBAC”) and G molar ratio TBAC: G = 1: 3 mixture (non-patent Reference 4; hereinafter referred to as “deep eutectic solvent TBAC-G3”, a mixture of TBAC and G molar ratio TBAC: G = 1: 4 (see Non-Patent Document 4; hereinafter referred to as “deep eutectic solvent”) "TBAC-G4"), T Mixture of AC and G molar ratio TBAC: G = 1: 5 (see Non-Patent Document 4; hereinafter referred to as “deep eutectic solvent TBAC-G5”), molar ratio TBAC to EG TBAC: EG = 1: 3 mixture (see non-patent document 4; hereinafter referred to as “deep eutectic solvent TBAC-EG3”), TBAC: EG molar ratio TBAC: EG = 1: 4 mixture (see non-patent document 4) Hereinafter referred to as “deep eutectic solvent TBAC-EG4”) and a mixture of TBAC and lactic acid (hereinafter abbreviated as “LA”) in a molar ratio TBAC: LA = 1: 2 (see Non-Patent Document 5) Hereinafter referred to as “deep eutectic solvent TBAC-LA2”).

[Method for producing deep eutectic solvent]
The deep eutectic solvent used in the following examples was prepared by the following method with reference to Non-Patent Documents 1 to 3. That is, first, a powdered halogen salt (ChCl or TBAC) and a powder or liquid hydrogen bond donor (G, EG, or LA) are placed in a desired molar amount in a glass vial (20 mL in volume) that has been washed. It fractionated so that it might become ratio. Next, the contents of the vial were stirred with a stir bar for about 10 minutes while the vial was heated at 80 ° C. with a hot stirrer (magnetic stirrer with a hot plate) to obtain a deep eutectic solvent as a colorless transparent liquid. .

[Example 1]
First, a toluene solution of meso-tetraphenyl-tetrabenzoporphyrin palladium as an organic photosensitizing molecule (A) (concentration in this solution: 2.0 ×) in a glass vial (with a capacity of 15 mL) that has been washed. 10 ⁻⁴ M, final concentration in sample: 1 × 10 ⁻⁵ M) 20 μL, and toluene solution of perylene as organic light emitting molecule (B) (concentration in this solution: 4.0 × 10 ⁻³ M, in sample) Final concentration: 3 × 10 ⁻³ M) and 300 μL.

  The vial was then placed in a vacuum vessel and evacuated for 10 minutes with a scroll pump. Thereby, toluene volatilized and the fine powder of the organic photosensitization molecule | numerator (A) and the organic light emitting molecule | numerator (B) deposited on the inner wall face of a vial bottle. Thereafter, the vial was taken out into the atmosphere.

  Next, 400 μL of deep eutectic solvent TBAC-G3 was taken into the vial. The vial was placed on a hot stirrer and heated at 80 ° C. with stirring with a stir bar for about 10 minutes. It was visually confirmed that the fine powders of the organic photosensitizing molecule (A) and the organic light emitting molecule (B) were dissolved in a deep eutectic solvent to become a transparent liquid. The vial was placed in a vacuum container and evacuated (deoxygenated) for 2 hours with a scroll pump (same as previously used) to obtain a light wavelength conversion element.

  Move the vial containing the optical wavelength conversion element into the inside of the argon atmosphere groove box. In the argon atmosphere, the optical wavelength conversion element is a quartz tube (inner size 1 mm x 1 mm, outer dimension 2 mm x 2 mm, 25 mm long square The sample for measurement of the light wavelength conversion element was obtained by injecting into a cross-sectional one-end closed tube) and sealing the opening with solder. A sample for measurement was taken out from the groove box, and a light absorption spectrum and an up-conversion emission spectrum were measured.

  The light absorption spectrum of the measurement sample was measured with an ultraviolet-visible near-infrared spectrophotometer under an optical path length of 1 mm. The measured light absorption spectrum of the sample for measurement is shown in FIG.

  The up-conversion emission spectrum of the measurement sample was measured as follows. That is, for the measurement sample, continuous wave laser light (wavelength: 633 nm, output power: 6 mW, spot diameter: 0.8 mm) emitted from the continuous wave He-Ne laser emitter is used as the excitation light. Irradiated. Then, the light emitted from the measurement sample is converted into parallel light by a condensing lens arranged in a direction perpendicular to the incident excitation light, and then the parallel light is re-condensed to the entrance slit of the spectrometer by another lens. The spectrum of light emission (up-conversion light emission) was measured by an electronically cooled silicon CCD (Charge Coupled Device) detector installed behind the spectroscope. For the up-conversion emission spectrum measured in this way, the distortion of the spectrum shape due to the diffraction efficiency wavelength dependence of the diffraction grating mounted in the spectrometer and the detection sensitivity wavelength dependence of the electronically cooled silicon CCD detector is corrected. did. FIG. 4 shows an up-conversion (abbreviated as “UC” in the figure) emission spectrum of the measured measurement sample after correction.

[Example 2]
A sample for measuring an optical wavelength conversion element was obtained in the same manner as in Example 1 except that the deep eutectic solvent TBAC-G4 was used instead of the deep eutectic solvent TBAC-G3.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The upconversion emission spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. When the measurement sample was irradiated with continuous wave laser light under the same conditions as the measurement of the upconversion emission spectrum, blue light emission from the measurement sample was visually confirmed as shown in FIG.

Example 3
A sample for measuring an optical wavelength conversion element was obtained in the same manner as in Example 1 except that the deep eutectic solvent TBAC-G5 was used instead of the deep eutectic solvent TBAC-G3. A light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG.

Example 4
A sample for measuring an optical wavelength conversion element was obtained in the same manner as in Example 1 except that the deep eutectic solvent TBAC-LA2 was used instead of the deep eutectic solvent TBAC-G3.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG.

Example 5
Instead of the deep eutectic solvent TBAC-G3, the deep eutectic solvent TBAC-EG3 was used. Instead of the washed glass vial (content 15 mL), a cleaned glass vial (content 8 mL) was used. A sample for measurement of the light wavelength conversion element was obtained in the same manner as in Example 1 except that the vacuuming time after separating the deep eutectic solvent was changed from 2 hours to 1 hour.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG.

Example 6
A sample for measuring an optical wavelength conversion element was obtained in the same manner as in Example 5 except that the deep eutectic solvent TBAC-EG4 was used instead of the deep eutectic solvent TBAC-EG3.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG.

  As described above, the light wavelength conversion element in which the organic photosensitizing molecule (A) and the organic light emitting molecule (B) obtained in Examples 1 to 6 are dissolved in the deep eutectic solvent (C) is: It was confirmed that red light (light having a wavelength of 620 to 750 nm; light having a wavelength of 633 nm in Examples 1 to 6) can be up-converted to blue light having a shorter wavelength (light having a wavelength of 450 to 495 nm).

Example 7
First, 400 μL of a deep eutectic solvent TBAC-G4 was collected in a glass vial (internal volume: 15 mL) that had been washed. The vial was then placed in a vacuum vessel and evacuated (deoxygenated) for 2 hours with a scroll pump.

Next, the vial containing the deep eutectic solvent was transferred to the inside of a groove box in an argon atmosphere, and in the groove box, a methanol solution of 10-methyl-9-acridone as the organic photosensitizing molecule (A) (this solution) Concentration in the sample 1.0 × 10 ⁻³ M, final concentration in the sample: 1.15 × 10 ⁻⁴ M) and 46 μL of the organic light emitting molecule (B) in methanol solution (in this solution) A concentration of 2.0 × 10 ⁻² M and a final concentration in the sample: 5 × 10 ⁻³ M) of 100 μL were dispensed into vials. Next, the contents of the vial were agitated and homogenized by repeatedly “sucking / discharging” using a glass Pasteur pipette. Further, the contents of the vial were subjected to ultrasonic dispersion (stirring) with a bath sonicator (manufactured by Branson Ultrasonics Corporation, model number “3510”) for 5 minutes.

  Next, the vial was moved into a vacuum container and evacuated with a scroll pump for 1 hour to remove methanol. Thereby, an optical wavelength conversion element was obtained.

  Move the vial containing the optical wavelength conversion element into the inside of the argon atmosphere groove box. In the argon atmosphere, the optical wavelength conversion element is a quartz tube (inner size 1 mm x 1 mm, outer dimension 2 mm x 2 mm, 25 mm long square The sample for measurement of the light wavelength conversion element was obtained by injecting into a cross-sectional one-end closed tube) and sealing the opening with solder. A sample for measurement was taken out from the groove box, and a light absorption spectrum and an up-conversion emission spectrum were measured. The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG.

  The up-conversion emission spectrum of the measurement sample is a continuous wave laser beam (wavelength) emitted from a continuous wave diode laser emitter instead of a continuous wave laser beam emitted from a continuous wave He-Ne laser emitter as excitation light. : 405 nm, output power: 3 mW, spot diameter: 0.8 mm) was measured in the same manner as in Example 1 except that the measurement sample was irradiated. FIG. 17 shows the measured upconversion emission spectrum of the measurement sample.

Example 8
Instead of methanol solution of 1-methylnaphthalene (concentration 2.0 × 10 ⁻² M in this solution, final concentration in sample: 5 × 10 ⁻³ M) as organic luminescent molecule (B), methanol solution of acenaphthene ( Sample for measuring optical wavelength conversion element in the same manner as in Example 7 except that the concentration in the solution was 2.0 × 10 ⁻² M and the final concentration in the sample was 5 × 10 ⁻³ M). Got.

  A light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 7 is shown in FIG.

Example 9
Instead of 1,1-methylnaphthalene in methanol (concentration 2.0 × 10 ⁻² M in this solution, final concentration in the sample: 5 × 10 ⁻³ M) as the organic luminescent molecule (B) Except that a methanol solution of tert-butylnaphthalene (concentration 2.0 × 10 ⁻² M in this solution, final concentration in the sample: 5 × 10 ⁻³ M) was used, the same as in Example 7 A sample for measurement of the light wavelength conversion element was obtained. A light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 7 is shown in FIG.

Example 10
Methanol solution of 10-methyl-9-acridone as organic photosensitizer molecule (A) (concentration in this solution: 1.0 × 10 ⁻³ M, final concentration in sample: 1.15 × 10 ⁻⁴ M) Instead of 46 μL, organic solution was obtained using 53 μL of 10-methyl-9-acridone in methanol (concentration 1.0 × 10 ⁻³ M in this solution, final concentration in sample: 1.33 × 10 ⁻⁴ M). 2,6-di-tert instead of 1-methylnaphthalene in methanol (concentration 2.0 × 10 ⁻² M in this solution, final concentration in sample: 5 × 10 ⁻³ M) as molecule (B) A light solution in the same manner as in Example 7 except that a methanol solution of butylnaphthalene (concentration 2.0 × 10 ⁻² M in this solution, final concentration in the sample: 5 × 10 ⁻³ M) was used. A sample for measuring the wavelength conversion element was obtained. The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG.

  The up-conversion emission spectrum of the measurement sample is a continuous wave laser beam (wavelength) emitted from a continuous wave diode laser emitter instead of a continuous wave laser beam emitted from a continuous wave He-Ne laser emitter as excitation light. : 405 nm, output power: 3 mW, spot diameter: 0.8 mm), and a 400 nm short pass filter is placed in the incident optical path to the entrance slit of the spectrometer, and the diffraction grating mounted in the spectrometer Except that the distortion of the spectral shape due to the diffraction efficiency wavelength dependency of the above, the detection sensitivity wavelength dependency of the electronic cooling silicon CCD detector, and the transmittance wavelength dependency of the 400 nm short pass filter were corrected, the same as in Example 1. It was measured. FIG. 23 shows the measured upconversion emission spectrum of the measurement sample.

Example 11
Using the deep eutectic solvent TBAC-EG4 instead of the deep eutectic solvent TBAC-G4, the step of evacuating (deoxygenating) the vial bottle containing only the deep eutectic solvent with a scroll pump for 2 hours is omitted (evacuation) ), Fractionation of organic photosensitized molecules (A) and organic luminescent molecules (B), stirring and homogenization using a glass Pasteur pipette, and ultrasonic A sample for measuring an optical wavelength conversion element was obtained in the same manner as in Example 10 except that the dispersion was performed in the air.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 10 is shown in FIG.

Example 12
Methanol solution of 10-methyl-9-acridone as organic photosensitizer molecule (A) (concentration in this solution: 1.0 × 10 ⁻³ M, final concentration in sample: 1.15 × 10 ⁻⁴ M) Instead of 46 μL, organic solution was obtained using 53 μL of 10-methyl-9-acridone in methanol (concentration 1.0 × 10 ⁻³ M in this solution, final concentration in sample: 1.33 × 10 ⁻⁴ M). Instead of methanol solution of 1-methylnaphthalene (concentration 2.0 × 10 ⁻² M in this solution, final concentration in sample: 5 × 10 ⁻³ M) as molecule (B), methanol solution of acenaphthene (this solution) The sample for measurement of the light wavelength conversion element was obtained in the same manner as in Example 7 except that the concentration in the sample was 2.0 × 10 ⁻² M and the final concentration in the sample was 5 × 10 ⁻³ M). It was.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. FIG. 27 shows the up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 10.

Example 13
A sample for measuring an optical wavelength conversion element was obtained in the same manner as in Example 12 except that the deep eutectic solvent ChCl-G2 was used instead of the deep eutectic solvent TBAC-G4.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 10 is shown in FIG.

Example 14
Using the deep eutectic solvent TBAC-EG4 instead of the deep eutectic solvent TBAC-G4, the step of evacuating (deoxygenating) the vial bottle containing only the deep eutectic solvent with a scroll pump for 2 hours is omitted (evacuation) ), Fractionation of organic photosensitized molecules (A) and organic luminescent molecules (B), stirring and homogenization using a glass Pasteur pipette, and ultrasonic A sample for measuring an optical wavelength conversion element was obtained in the same manner as in Example 12 except that the dispersion was performed in the air.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 10 is shown in FIG.

Example 15
Using the deep eutectic solvent ChCl-EG2 instead of the deep eutectic solvent TBAC-G4, the process of evacuating (deoxygenating) the vial bottle containing only the deep eutectic solvent with a scroll pump for 2 hours is omitted (evacuation) ), Fractionation of organic photosensitized molecules (A) and organic luminescent molecules (B), stirring and homogenization using a glass Pasteur pipette, and ultrasonic A sample for measuring an optical wavelength conversion element was obtained in the same manner as in Example 12 except that the dispersion was performed in the air.

  The light absorption spectrum of the measurement sample measured in the same manner as in Example 1 is shown in FIG. The up-conversion emission spectrum of the measurement sample measured in the same manner as in Example 10 is shown in FIG.

  As described above, the light wavelength conversion element in which the organic photosensitizing molecule (A) and the organic light emitting molecule (B) obtained in Examples 7 to 15 are dissolved in the deep eutectic solvent (C) is: It was confirmed that visible light (light having a wavelength of 400 nm or more; purple light having a wavelength of 405 nm in Examples 7 to 15) can be up-converted to ultraviolet light having a shorter wavelength (light having a wavelength of 350 nm or less).

DESCRIPTION OF SYMBOLS 1 Solar cell layer 2 Transparent back electrode 3 Transparent insulating film 4 Up-conversion layer 5 Light reflection film 7 Light-receiving surface electrode 8 Glass channel 9 Gas 10 Water added with photocatalyst 11 Mechanical support

Claims (6)

  The organic photosensitizing molecule (A) and the organic light emitting molecule (B), which are a combination showing a triplet-triplet annihilation process, are dissolved and / or dispersed in a deep eutectic solvent (C). Light wavelength conversion element.   The deep eutectic solvent (C) is a mixture of a non-metallic halogen salt that is solid at room temperature (25 ° C.) and a hydrogen bond donor that is solid or liquid at room temperature (25 ° C.), and at room temperature (25 ° C.). The light wavelength conversion element according to claim 1, wherein the light wavelength conversion element is a mixture of liquids.   A solar cell using the light wavelength conversion element according to claim 1.   A photocatalyst using the light wavelength conversion element according to claim 1.   A photocatalytic hydrogen / oxygen generator using the light wavelength conversion element according to claim 1. An optical up-conversion filter that converts light into shorter wavelength light,
The optical wavelength conversion element according to claim 1 or 2,
With a cell,
An optical up-conversion filter, wherein the optical wavelength conversion element is enclosed in the cell.