Photoelectric conversion element

Abstract

To provide a photoelectric conversion element which has a high sensitivity against a light of a near infrared region, and has less time degradation.SOLUTION: A photoelectric conversion element is formed by having a photoelectric conversion layer in between a pair of electrodes. The photoelectric conversion layer contains a coloring agent expressed by a specific formula. In the specific formula, each of R11 to R30 is an alkyl group which independently may include: a hydrogen atom and a substituent group; and an amino group which may contain: a cycloalkyl group; an alkoxy group; an aryl group; an aryloxy group; a carboxy group; an alkoxycarbonyl group; a halogen atom; a nitro group; a cyano group; or a substituent group. Any two or more of R11 to R20 and / or any two or more of R21 to R30 may form a cycle by being connected to each other.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a photoelectric conversion element, a photoelectric conversion layer and a photoelectric conversion material for forming the same, and an image sensor and a solar cell using the same. [Background technology]

[0002] Photoelectric conversion elements are elements that convert light into electricity, and applications to solar cells and the like have been attempted. Silicon has been used as a photoelectric conversion material for photoelectric conversion elements for some time. However, silicon has poor absorption of light in the near-infrared region, so near-infrared light cannot be effectively used for photoelectric conversion, and there has been a problem of low photoelectric conversion efficiency. In addition, photoelectric conversion elements often deteriorate over time due to water, oxygen, and the like, because electrons are exchanged in the photoelectric conversion material in the element when converting light into electricity. In particular, when an organic compound is used as the photoelectric conversion material, there has been a problem of a high tendency for deterioration over time. On the other hand, squarylium-based compounds have been disclosed as compounds that absorb near-infrared light (Patent Document 1, Patent Document 2, etc.), but it was unclear whether these compounds have photoelectric conversion ability. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-198816 A [Patent Document 2] JP 2019-211764 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a photoelectric conversion element that has high sensitivity to light in the near-infrared region and is less susceptible to deterioration over time. [Means for solving the problem]

[0005] The present inventors have conducted extensive research to solve the above problems, and have arrived at the present invention. That is, the present invention relates to a photoelectric conversion element having a photoelectric conversion layer between a pair of electrodes, the photoelectric conversion layer containing a dye represented by the following general formula (1) or (2).

[0006] [ka]

[0007] In general formula (1), R 11 ~R 30 R each independently represents a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group, an alkoxy group, an aryl group, an aryloxy group, a carboxy group, an alkoxycarbonyl group, a halogen atom, a nitro group, a cyano group, or an amino group which may have a substituent. 11 ~R 20 Any two or more of the above and / or R 21 ~R 30 Any two or more of may be bonded to each other to form a ring.

[0008] [ka]

[0009] In general formula (2), R 41 ~R 56 R each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, a halogen atom, an acetamide group, a carboxy group, a hydroxyl group, an amino group which may have a substituent, or a phenyl group. 41 ~R 56 Among these, adjacent two may be bonded to each other to form a ring.

[0010] The present invention also relates to the above photoelectric conversion element, wherein the photoelectric conversion layer further contains a dispersing agent (D).

[0011] The present invention also relates to the above photoelectric conversion element, wherein the dispersant (D) has an amine value of 10 to 200 mgKOH / g or a quaternary ammonium salt value of 10 to 90 mgKOH / g.

[0012] The present invention also relates to a photoelectric conversion layer for forming the above-mentioned photoelectric conversion element, the photoelectric conversion layer containing a dye represented by the above-mentioned general formula (1) or general formula (2).

[0013] The present invention also relates to a photoelectric conversion material for forming the above-mentioned photoelectric conversion element, which contains a dye represented by the above-mentioned general formula (1) or (2).

[0014] The present invention also relates to an image sensor having the above-mentioned photoelectric conversion element.

[0015] The present invention also relates to a solar cell having the above photoelectric conversion element. Effect of the Invention

[0016] The present invention makes it possible to provide a photoelectric conversion element that has high sensitivity to light in the near-infrared region and is less susceptible to deterioration over time. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The present invention will be described in detail below, but first, the terms and abbreviations used in this specification will be described. A photoelectric conversion material containing a dye represented by general formula (1) will be referred to as "photoelectric conversion material (A)", and a photoelectric conversion material containing a dye represented by general formula (2) will be referred to as "photoelectric conversion material (B)". In addition, unless otherwise specified, "parts" means "parts by mass" and "%" means "% by mass".

[0018] <Dyes represented by general formula (1) and general formula (2)> First, the dyes represented by formulae (1) and (2) used in the present invention will be described. The groups in formulae (1) and (2) will be described.

[0019] Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a 2-methylethyl group, etc. Examples of the substituent on the alkyl group include a phenyl group, etc.

[0020] Examples of the cycloalkyl group include a cyclohexyl group, a cyclopentyl group, a cycloheptyl group, and a cyclooctyl group.

[0021] Examples of the alkenyl group include an ethenyl group, a propenyl group, a 1-butenyl group, an isobutenyl group, a 1-pentenyl group, a 2-pentenyl group, a 2-methyl-1-butenyl group, and a 1-vinylhexyl group.

[0022] Examples of the alkoxy group include a methoxy group, an ethoxy group, and a propoxy group.

[0023] Examples of the aryl group include a phenyl group, a 1-naphthyl group, a 2-naphthyl group, a 2-anthryl group, a 1-phenanthryl group, a 2-phenanthryl group, a 3-phenanthryl group, a 1-pyrenyl group, a 2-pyrenyl group, a 2-perylenyl group, a 3-perylenyl group, a 2-fluorenyl group, a 3-fluorenyl group, a 7-fluorenyl group, and an 8-fluorenyl group.

[0024] Examples of the aryloxy group include a phenoxy group, a 1-naphthyloxy group, and a 2-naphthyloxy group.

[0025] Examples of the alkoxycarbonyl group include a methoxycarbonyl group, an ethoxycarbonyl group, and an isopropoxycarbonyl group.

[0026] The halogen atom is fluorine, chlorine, bromine or iodine.

[0027] Substituents on the amino group include alkyl groups such as methyl, ethyl, propyl, and 2-methylethyl groups.

[0028] In the general formula (1), R 11 ~R 20Any two or more of the above and / or R 21 ~R 30 Any two or more of R may be bonded to each other to form a ring. 41 ~R 56 Among these, adjacent two may be bonded to each other to form a ring. For example, R 11 and R 13 and are both alkyl groups and are "bonded to each other" means that R 11 and R 13 and are bonded via an alkylene group. 41 ~R 56 When adjacent two of these are bonded to each other to form a ring, the ring formed is preferably an aromatic ring, more preferably a benzene ring.

[0029] From the viewpoint of durability, R in general formula (1) 11 ~R 14 , R 17 ~R 20 , R 21 ~R 24 and R 27 ~R 30 It is preferable that at least one of R is a methyl group. 11 and R 19 And R 21 and R 29 , or R 13 and R 17 And R 23 and R 27 It is more preferable that any combination of R in the general formula (2) is a methyl group. 41 ~R 56 is preferably a hydrogen atom, or two adjacent groups are bonded to each other to form a ring.

[0030] <Photoelectric conversion materials> The photoelectric conversion material of the present invention is characterized by containing a dye represented by general formula (1) or general formula (2). In this specification, a photoelectric conversion material containing a dye represented by general formula (1) is referred to as "photoelectric conversion material (A)", and a photoelectric conversion material containing a dye represented by general formula (2) is referred to as "photoelectric conversion material (B)". The photoelectric conversion material (A) and the photoelectric conversion material (B) may be used alone or in combination of two or more kinds.

[0031] <Photoelectric conversion element forming composition (P)> The photoelectric conversion material of the present invention can be mixed with an organic solvent or the like described below to form a photoelectric conversion element-forming composition (P) for forming a photoelectric conversion film. The content of the photoelectric conversion material in the photoelectric conversion element-forming composition (P) is preferably 0.01 to 90%, more preferably 10 to 80%.

[0032] <Organic solvent> As the organic solvent, a known organic solvent can be used, but it is preferable to use one that can dissolve or uniformly disperse the photoelectric conversion material in order to form a uniform photoelectric conversion film.Specific examples of the organic solvent include, but are not limited to, alcohol-based solvents such as 1,3-butanediol and 1,3-butylene glycol, ketone-based solvents such as methyl isobutyl ketone and cyclohexanone, and ester-based solvents such as isoamyl acetate and propylene glycol monomethyl ether acetate.The organic solvent can be used alone or in combination of two or more kinds.

[0033] <Dispersant (D)> The photoelectric conversion layer of the present invention may contain a dispersant (D). The dispersant (D) is incorporated into the photoelectric conversion layer by forming the photoelectric conversion layer after the dispersant (D) is incorporated into the composition for forming a photoelectric conversion element (P). The dispersant (D) preferably has an amine value or a quaternary ammonium salt value. When the dispersant (D) has an amine value, the amine value is preferably from 10 to 200 mgKOH / g, more preferably from 20 to 200 mgKOH / g, further preferably from 60 to 150 mgKOH / g, and particularly preferably from 60 to 120 mgKOH / g.

[0034] When the dispersant (D) has a quaternary ammonium salt value, the quaternary ammonium salt value is preferably 10 to 90 mgKOH / g, and more preferably 15 to 50 mgKOH / g. The quaternary ammonium salt value in this specification is a value obtained by titrating with a 0.1 N silver nitrate aqueous solution using a 5% potassium chromate aqueous solution as an indicator, and then converting the value into the equivalent amount of potassium hydroxide, and is a value (mgKOH / g) obtained by converting the measured total ammonium salt value into the solid content of the dispersant.

[0035] The weight average molecular weight (sometimes abbreviated as Mw) of the dispersant (D) is preferably 4,000 to 40,000, more preferably 5,000 to 20,000, in terms of standard polystyrene. As the dispersant (D), a known dispersant can be used. For example, the basic resin-type dispersant (B) described in JP-A-2019-211764 is one of the preferred embodiments.

[0036] <Other additives> The photoelectric conversion layer or photoelectric conversion element forming composition (P) of the present invention may contain other additives other than the above-mentioned photoelectric conversion material, organic solvent, and dispersant (D). Examples of other additives include a surfactant and a binder (binding agent).

[0037] <Photoelectric conversion element> The photoelectric conversion element of the present invention is characterized in that it has a photoelectric conversion layer between a pair of electrodes, and the photoelectric conversion layer contains a dye represented by the following general formula (1) or general formula (2). The photoelectric conversion element can be manufactured by a known element configuration and manufacturing method, for example, by the manufacturing method described in JP 2015-065267 A. Examples of materials for the electrodes constituting the photoelectric conversion element include known materials such as conductive metal oxides such as tin oxide, zinc oxide, indium oxide, and indium tin oxide (ITO), and metals such as gold, silver, platinum, chromium, nickel, lithium, indium, aluminum, calcium, and magnesium.

[0038] <Image sensor> The image sensor of the present invention arranges a large number of photoelectric conversion elements of the present invention in an array, and recognizes not only the amount of incident light but also information on the position of incidence by applying a voltage between a pair of electrodes from outside the photoelectric conversion element.

[0039] <Solar cells> The solar cell of the present invention can use the photoelectric conversion element of the present invention as it is, or can be waterproofed by using a frame or a back sheet depending on the installation environment. The photoelectric conversion element generates electricity by being irradiated with light without applying a voltage to the photoelectric conversion element from the outside. EXAMPLES

[0040] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples as long as it does not depart from the gist of the invention. In the examples and comparative examples, "parts" and "%" mean "parts by mass" and "% by mass", respectively.

[0041] <Synthesis of dispersant (D)> Dispersants (D1-1) to (D1-27) and (D2-1) to (D2-10) were synthesized according to the method described in paragraphs

[0199] to

[0232] of JP 2019-211764 A. The correspondence table between the dispersants synthesized here and the basic resin-type dispersants described in JP 2019-211764 A is shown in Table 1 below.

[0042] [Table 1]

[0043] <Production of photoelectric conversion materials> The photoelectric conversion material was identified using MALDITOF-MS spectrum (hereinafter abbreviated as "TOF-MS"). The MALDITOF-MS spectrum was obtained using a Bruker Daltonics MALDI mass spectrometer AutoflexIII, and the photoelectric conversion material was identified based on the agreement between the molecular ion peak of the obtained mass spectrum and the mass number obtained by calculation. In this example, the dye belonging to general formula (1) was designated as photoelectric conversion material (A), and the dye belonging to general formula (2) was designated as photoelectric conversion material (B).

[0044] (Photoelectric Conversion Material (A)) Example 1 (Photoelectric Conversion Material [A-1]) 400 parts of toluene were mixed with 40.0 parts of 1,8-diaminonaphthalene, 25.1 parts of cyclohexanone, and 0.087 parts of p-toluenesulfonic acid monohydrate, and the mixture was heated and stirred in a nitrogen gas atmosphere and refluxed for 3 hours. Water generated during the reaction was removed from the system by azeotropic distillation. After the reaction was completed, the dark brown solid obtained by distilling toluene was extracted with acetone and purified by recrystallization from a mixed solvent of acetone and ethanol. The obtained brown solid was dissolved in a mixed solvent of 240 parts of toluene and 160 parts of n-butanol, 13.8 parts of 3,4-dihydroxy-3-cyclobutene-1,2-dione were added, and the mixture was heated and stirred in a nitrogen gas atmosphere and refluxed for 8 hours. Water generated during the reaction was removed from the system by azeotropic distillation. After the reaction was completed, the solvent was distilled, and 200 parts of hexane were added while stirring the resulting reaction mixture. The resulting black-brown precipitate was filtered off, washed with hexane, ethanol, and acetone, and dried under reduced pressure to obtain 61.9 parts (yield: 92%) of photoelectric conversion material [A-1]. As a result of mass analysis using TOF-MS, it was identified as photoelectric conversion material [A-1].

[0045] Example 2 (Photoelectric Conversion Material [A-2]) The same procedure as in the production of photoelectric conversion material [A-1] was carried out except that 32.2 parts of 2,6-dimethylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1], and 71.9 parts of photoelectric conversion material [A-2] (yield: 97%) was obtained. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-2].

[0046] Example 3 (Photoelectric Conversion Material [A-3]) Photoelectric conversion material [A-3] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 32.2 parts of 3,5-dimethylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-3].

[0047] Example 4 (Photoelectric Conversion Material [A-4]) Photoelectric conversion material [A-4] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 28.6 parts of 4-methylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry using TOF-MS, it was identified as photoelectric conversion material [A-4].

[0048] Example 5 (Photoelectric Conversion Material [A-5]) Photoelectric conversion material [A-5] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 35.8 parts of 3,3,5-trimethylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry by TOF-MS, it was identified as photoelectric conversion material [A-5].

[0049] Example 6 (Photoelectric Conversion Material [A-6]) Photoelectric conversion material [A-6] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 32.2 parts of 4-ethylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry using TOF-MS, it was identified as photoelectric conversion material [A-6].

[0050] Example 7 (Photoelectric Conversion Material [A-7]) Photoelectric conversion material [A-7] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 35.8 parts of 4-propylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry using TOF-MS, it was identified as photoelectric conversion material [A-7].

[0051] Example 8 (Photoelectric Conversion Material [A-8]) Photoelectric conversion material [A-8] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 46.0 parts of 2-cyclohexylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-8].

[0052] Example 9 (Photoelectric Conversion Material [A-9]) Photoelectric conversion material [A-9] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 28.1 parts of 2-norbornanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-9].

[0053] Example 10 (Photoelectric Conversion Material [A-10]) Photoelectric conversion material [A-10] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 2-phenylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry by TOF-MS, it was identified as photoelectric conversion material [A-10].

[0054] Example 11 (Photoelectric Conversion Material [A-11]) Photoelectric conversion material [A-11] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 48.1 parts of 4-p-tolylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-11].

[0055] Example 12 (Photoelectric Conversion Material [A-12]) Photoelectric conversion material [A-12] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 48.1 parts of 4-benzylcyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-12].

[0056] Example 13 (Photoelectric Conversion Material [A-13]) Photoelectric conversion material [A-13] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 36.3 parts of 4-ethoxycyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-13].

[0057] Example 14 (Photoelectric Conversion Material [A-14]) Photoelectric conversion material [A-14] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 48.6 parts of 4-phenoxycyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-14].

[0058] Example 15 (Photoelectric Conversion Material [A-15]) Photoelectric conversion material [A-15] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 39.6 parts of 4-acetamidocyclohexane was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-15].

[0059] Example 16 (Photoelectric Conversion Material [A-16]) Photoelectric conversion material [A-16] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 36.3 parts of 4-oxocyclohexane carboxylic acid was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry using TOF-MS, it was identified as photoelectric conversion material [A-16].

[0060] Example 17 (Photoelectric Conversion Material [A-17]) Photoelectric conversion material [A-17] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 43.5 parts of ethyl 2-oxocyclohexanecarboxylate were used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry using TOF-MS, it was identified as photoelectric conversion material [A-17].

[0061] Example 18 (Photoelectric Conversion Material [A-18]) Photoelectric conversion material [A-18] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 28.9 parts of 4-aminocyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry using TOF-MS, it was identified as photoelectric conversion material [A-18].

[0062] Example 19 (Photoelectric Conversion Material [A-19]) Photoelectric conversion material [A-19] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 36.1 parts of 4-(dimethylamino)cyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry by TOF-MS, it was identified as photoelectric conversion material [A-19].

[0063] Example 20 (Photoelectric Conversion Material [A-20]) Photoelectric conversion material [A-20] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 50.6 parts of 4-oxo-20-phenylcyclohexanecarbonitrile was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass analysis by TOF-MS, it was identified as photoelectric conversion material [A-20].

[0064] Example 21 (Photoelectric Conversion Material [A-21]) Photoelectric conversion material [A-21] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 36.5 parts of 2-nitrocyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry using TOF-MS, it was identified as photoelectric conversion material [A-21].

[0065] Example 22 (Photoelectric Conversion Material [A-22]) Photoelectric conversion material [A-22] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 33.8 parts of 2-chlorocyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry using TOF-MS, it was identified as photoelectric conversion material [A-22].

[0066] Example 23 (Photoelectric Conversion Material [A-23]) Photoelectric conversion material [A-23] was obtained by the same procedure as in the production of photoelectric conversion material [A-1], except that 29.6 parts of 2-fluorocyclohexanone was used instead of 25.1 parts of cyclohexanone used in the production of photoelectric conversion material [A-1]. As a result of mass spectrometry by TOF-MS, it was identified as photoelectric conversion material [A-23]. The structure of the obtained photoelectric conversion material (A) is shown below.

[0067] [ka]

[0068] [ka]

[0069] [ka]

[0070] Example 24 (Production of photoelectric conversion material (B)) <Photoelectric Conversion Material (B)> [Photoelectric conversion materials [B-1]] 400 parts of toluene were mixed with 40.0 parts of 1,8-diaminonaphthalene, 46.0 parts of 9-fluorenone, and 0.087 parts of p-toluenesulfonic acid monohydrate, and the mixture was heated and stirred in a nitrogen gas atmosphere and refluxed for 3 hours. Water generated during the reaction was removed from the system by azeotropic distillation. After the reaction was completed, the dark brown solid obtained by distilling toluene was extracted with acetone and purified by recrystallization from a mixed solvent of acetone and ethanol. The obtained brown solid was dissolved in a mixed solvent of 240 parts of toluene and 160 parts of n-butanol, 13.8 parts of 3,4-dihydroxy-3-cyclobutene-1,2-dione were added, and the mixture was heated and stirred in a nitrogen gas atmosphere and refluxed for 8 hours. Water generated during the reaction was removed from the system by azeotropic distillation. After the reaction was completed, the solvent was distilled, and 200 parts of hexane were added while stirring the resulting reaction mixture. The resulting black-brown precipitate was filtered off, washed with hexane, ethanol, and acetone, and dried under reduced pressure to obtain 84.6 parts (yield: 97%) of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-1].

[0071] Example 25 [Photoelectric conversion material [B-2]] Photoelectric conversion material [B-2] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 46.0 parts of 2-methyl-9H-fluoren-9-one was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-2].

[0072] Example 26 [Photoelectric conversion material [B-3]] Photoelectric conversion material [B-3] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 53.1 parts of 2,7-dimethyl-9H-fluoren-9-one was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-3].

[0073] Example 27 [Photoelectric conversion material [B-4]] Photoelectric conversion material [B-4] was obtained by carrying out the same operation as in the production of photoelectric conversion material [B-1], except that 53.1 parts of 2,6-dimethyl-9H-fluoren-9-one was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-4].

[0074] Example 28 [Photoelectric conversion material [B-5]] Photoelectric conversion material [B-5] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 58.7 parts of 7H-benzo[c]fluoren-7-one was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-5].

[0075] Example 29 [Photoelectric conversion material [B-6]] Photoelectric conversion material [B-6] was obtained by carrying out the same operation as in the production of photoelectric conversion material [B-1], except that 91.8 parts of 4-methoxy-9-fluorenone was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-6].

[0076] Example 30 [Photoelectric conversion material [B-7]] Photoelectric conversion material [B-7] was obtained by carrying out the same operation as in the production of photoelectric conversion material [B-1], except that 57.2 parts of 9-fluorene-4-carboxylic acid was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-7].

[0077] Example 31 [Photoelectric conversion material [B-8]] Photoelectric conversion material [B-8] was obtained by carrying out the same operation as in the production of photoelectric conversion material [B-1], except that 50.0 parts of 2-hydroxy-9-fluorene were used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-8].

[0078] Example 32 [Photoelectric conversion material [B-9]] Photoelectric conversion material [B-9] was obtained by carrying out the same operation as in the production of photoelectric conversion material [B-1], except that 54.1 parts of 2,7-dihydroxy-9H-fluoren-9-one was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-9].

[0079] Example 33 [Photoelectric conversion material [B-10]] Photoelectric conversion material [B-10] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 49.8 parts of 2-amino-9-fluorenone was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-10].

[0080] Example 34 [Photoelectric conversion material [B-11]] Photoelectric conversion material [B-11] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 56.9 parts of 2-dimethylamino-9-fluorenone was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-11].

[0081] Example 35 [Photoelectric conversion material [B-12]] Photoelectric conversion material [B-12] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 66.1 parts of 2-bromo-9-fluorenone was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-12].

[0082] Example 36 [Photoelectric conversion material [B-13]] Photoelectric conversion material [B-13] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 50.5 parts of 2-fluoro-9-fluorenone was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-13].

[0083] Example 37 [Photoelectric conversion material [B-14]] Photoelectric conversion material [B-14] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 63.5 parts of 2,7-dichloro-9-fluorenone was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-14].

[0084] Example 38 [Photoelectric conversion material [B-15]] Photoelectric conversion material [B-15] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 63.5 parts of 2,4-dichloro-9-fluorenone was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-15].

[0085] Example 39 [Photoelectric conversion material [B-16]] Photoelectric conversion material [B-16] was obtained by the same procedure as in the production of photoelectric conversion material [B-1], except that 49.8 parts of 2-acetamido-9-fluorenone was used instead of 46.0 parts of 9-fluorenone used in the production of photoelectric conversion material [B-1]. As a result of mass spectrometry and elemental analysis by TOF-MS, it was identified as photoelectric conversion material [B-16]. The structure of the obtained photoelectric conversion material (B) is shown below.

[0086] [ka]

[0087] [ka]

[0088] <Production of photoelectric conversion element forming composition (P)> (Photoelectric conversion element forming composition (P-1)) The following materials were mixed and stirred to be uniform, then dispersed in an Eiger mill using zirconia beads having a diameter of 0.5 mm for 3 hours, and filtered through a 0.5 μm filter to produce a photoelectric conversion element forming composition (P-1). Photoelectric conversion material [A-1]: 0.94 parts Dispersant [D1-1] solution: 0.56 parts Propylene glycol monomethyl ether acetate (solvent): 8.50 parts

[0089] (Production of compositions for forming photoelectric conversion elements (P-2 to 41 and PR-1 to 2)) Photoelectric conversion material compositions (P-2 to 41 and PR-1 to 2) were produced in the same manner as the photoelectric conversion material composition (P-1), except that the photoelectric conversion material and the basic resin-type dispersant were changed to the compositions shown in Table 2. The abbreviation AR-1 in Table 2 represents a comparative photoelectric conversion material, which is a compound having the following structure.

[0090] [ka]

[0091] [Table 2]

[0092] <Creating a photoelectric conversion element> Example 40 (Photoelectric conversion element (E-1)) On a cleaned glass plate with an ITO electrode, PEDOT:PSS (poly(3,4-ethylenedioxy)-2,5-thiophene / polystyrenesulfonic acid, Baytron P manufactured by Bayer) was formed as a charge injection buffer layer by spin coating to a thickness of 80 nm. Next, a composition for forming a photoelectric conversion element (P-1) was formed as a film of 80 nm by spin coating to form a photoelectric conversion layer. Furthermore, Al was vapor-deposited on the film to a thickness of 100 nm to form an electrode, thereby obtaining a photoelectric conversion element. The obtained element was transferred into a glove box with a moisture concentration and oxygen concentration of 1 ppm or less without exposing it to the air, and subjected to a sealing treatment.

[0093] Production of Examples 41 to 80 (Photoelectric Conversion Elements (E-2 to E-41) and Comparative Examples 1 and 2 (Comparative Photoelectric Conversion Elements ER-1 and ER-2) Photoelectric conversion elements (E-2 to E-41) and a comparative photoelectric conversion element (ER-1) were produced in the same manner as in Example 40, except that the photoelectric conversion element forming composition (P-1) was changed to a photoelectric conversion element forming composition shown in Table 3. An attempt was made to produce a comparative photoelectric conversion element (ER-2) in the same manner using the photoelectric conversion element forming composition (PR-2), but a uniform photoelectric conversion layer could not be obtained, and the element could not be produced.

[0094] <Photodiode evaluation 1> The fabricated photoelectric conversion element was taken out of the glove box, and the voltage-current curves in the dark and when irradiated with near-infrared light were measured in the range of -2 V to 2 V. An LED (light-emitting diode) with an emission wavelength of 850 nm was used as the light source, and the output voltage was 5 mW / cm. 2 The light intensity was adjusted to 1000 and the measurement was performed. The current value at a voltage of -1V was read off to determine the initial light / dark current ratio. The element was also stored in a desiccator at 80°C for 60 hours, and the light / dark current ratio after aging was similarly determined. The light / dark current ratio was judged according to the following criteria. The results are shown in Table 3. The higher the light / dark current ratio, the better. A practical range is one in which the judging criteria is 3 or more initially and 2 or more after aging. (Judgment criteria) 5: Bright / dark current ratio 200 or more 4: 100 to less than 200 3: Between 50 and 100 2: 20 to 50 1: Less than 20

[0095] <Photodiode evaluation 2> The manufactured photoelectric conversion element was taken out of the glove box and heat-treated on a hot plate at 100°C for 20 minutes. The photoelectric conversion efficiency (initial photoelectric conversion efficiency) of the element after heat treatment was measured. In addition, the photoelectric conversion efficiency (photoelectric conversion efficiency after aging) after continuous operation for 100 hours in an environment of 80°C was measured. The results are shown in Table 3.

[0096] The photoelectric conversion efficiency was 5 mW / cm using an LED with an emission wavelength of 850 nm as the light source. 2 The light intensity was adjusted to 0.04 cm. 2The IV curve characteristics were measured using a KEITHLEY MODEL 2400 source meter while irradiating light through a mask so that the IV curve characteristics were 100%. The conversion efficiency η was calculated according to the following formula using the set light source illuminance (W) and the Voc (open circuit voltage), Isc (short circuit current), and ff (fill factor) obtained from the IV curve characteristics measurement. The higher the photoelectric conversion efficiency, the better it is. The practical range is one in which the evaluation criteria are 3 or more initially and 2 or more after aging.

[0097]

number

[0098] (Judgment criteria) 5: Photoelectric conversion efficiency of 0.1% or more 4: 0.05% or more but less than 0.1% 3: 0.03% or more but less than 0.05% 2: 0.01% or more but less than 0.03% 1: Less than 0.01%

[0099] [Table 3]

[0100] As is clear from Table 3, the photoelectric conversion element of the present invention, as a photodiode, exhibits a high current ratio with and without light irradiation and shows little deterioration over time. As a solar cell, it has been shown to have high conversion efficiency and a long life.

[0101] <Fabrication and evaluation of image sensors> Sixteen photoelectric conversion elements (E-2) shown in Table 3 were fabricated. Next, 4 x 4 photoelectric conversion elements (E-2) were arranged on a flat surface to fabricate an image sensor. The fabricated image sensor was placed facing an image projected onto a screen installed in a darkroom using an LED with an emission wavelength of 850 nm as a light source. A voltage of -1 V was sequentially applied between the electrodes to determine the current ratio in the dark and when an image was projected. The current ratios determined for each photoelectric conversion element reproduced the brightness and darkness of the projected image, and it was confirmed that the image sensor worked.

[0102] <Solar cell evaluation> The photoelectric conversion element (E-2) shown in Table 3 was prepared. A solar simulator was used as the light source (USS-180S, manufactured by Ushio Inc.), and the light intensity (100 mW / cm) equivalent to sunlight (AM1.5) was used. 2 The exposed area of ​​the photoelectric conversion cell test sample was adjusted to 0.04 cm 2 The IV curve characteristics were measured using a KEITHLEY MODEL 2400 source meter while irradiating light through a mask so that the photoelectric conversion efficiency was 1.0 V. The photoelectric conversion efficiency was calculated in the same manner as in Photodiode Evaluation 2, and a judgment was made based on the judgment criteria. The judgment result was 3, and it was confirmed that the device can function as a solar cell. Furthermore, by using a tandem structure for the photoelectric conversion element that absorbs visible light, even higher photoelectric conversion efficiency is expected.

Claims

1. A photoelectric conversion element comprising a pair of electrodes and a photoelectric conversion layer between the electrodes, the photoelectric conversion layer containing a dye represented by the following general formula (1) or (2): 【Chemistry 1】 In general formula (1), R 11 ~R 30 R each independently represents a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group, an alkoxy group, an aryl group, an aryloxy group, a carboxy group, an alkoxycarbonyl group, a halogen atom, a nitro group, a cyano group, or an amino group which may have a substituent. 11 ~R 20 Any two or more of and / or R 21 ~R 30 any two or more of may be bonded to each other to form a ring, provided that R 11 , R 19 , R 21 and R 29 are all methyl groups, or R 13 , R 17 , R 23 and R 27 are all methyl groups. 【Chemistry 2】 In general formula (2), R 41 ~R 56 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, a halogen atom, an acetamide group, a carboxy group, a hydroxyl group, an amino group which may have a substituent, or a phenyl group. 41 ~R 56 Any two adjacent groups among these are bonded to each other to form a ring.

2. 2. The photoelectric conversion element according to claim 1, wherein the photoelectric conversion layer further contains a dispersing agent (D).

3. 3. The photoelectric conversion element according to claim 2, wherein the dispersant (D) has an amine value of 10 to 200 mgKOH / g or a quaternary ammonium salt value of 10 to 90 mgKOH / g.

4. A photoelectric conversion layer for forming the photoelectric conversion element according to any one of claims 1 to 3, comprising a dye represented by the following general formula (1) or (2): 【Chemistry 1】 In general formula (1), R 11 ~R 30 R each independently represents a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group, an alkoxy group, an aryl group, an aryloxy group, a carboxy group, an alkoxycarbonyl group, a halogen atom, a nitro group, a cyano group, or an amino group which may have a substituent. 11 ~R 20 Any two or more of and / or R 21 ~R 30 any two or more of may be bonded to each other to form a ring, provided that R 11 , R 19 , R 21 and R 29 are all methyl groups, or R 13 , R 17 , R 23 and R 27 are all methyl groups. 【Chemistry 2】 In general formula (2), R 41 ~R 56 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, a halogen atom, an acetamide group, a carboxy group, a hydroxyl group, an amino group which may have a substituent, or a phenyl group. 41 ~R 56 Any two adjacent groups among these are bonded to each other to form a ring.

5. A photoelectric conversion material for forming the photoelectric conversion element according to any one of claims 1 to 3, comprising a dye represented by the following general formula (1) or (2): 【Chemistry 1】 In general formula (1), R 11 ~R 30 R each independently represents a hydrogen atom, an alkyl group which may have a substituent, a cycloalkyl group, an alkoxy group, an aryl group, an aryloxy group, a carboxy group, an alkoxycarbonyl group, a halogen atom, a nitro group, a cyano group, or an amino group which may have a substituent. 11 ~R 20 Any two or more of and / or R 21 ~R 30 any two or more of may be bonded to each other to form a ring, provided that R 11 , R 19 , R 21 and R 29 are all methyl groups, or R 13 , R 17 , R 23 and R 27 are all methyl groups. 【Chemistry 2】 In general formula (2), R 41 ~R 56 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkoxy group, a halogen atom, an acetamide group, a carboxy group, a hydroxyl group, an amino group which may have a substituent, or a phenyl group. 41 ~R 56 Any two adjacent groups among these are bonded to each other to form a ring.

6. An image sensor comprising the photoelectric conversion element according to any one of claims 1 to 3.

7. A solar cell comprising the photoelectric conversion element according to any one of claims 1 to 3.

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