Material for photoelectric conversion element for imaging, and photoelectric conversion element for imaging using same

Abstract

Provided are: a material which achieves high sensitivity and high resolution of an imaging photoelectric conversion element; and an imaging photoelectric conversion element which uses the material. A material for a photoelectric conversion element for imaging, which is characterized by containing an indolocarbazole compound represented by general formula (1), and a photoelectric conversion element for imaging, which uses the material for a photoelectric conversion element for imaging. In general formula (1), ring B and an adjacent ring are condensed at an arbitrary position, and a six-membered ring represented by formula (1B) is represented. Ring C is condensed with an adjacent ring at an arbitrary position and represents a five-membered ring represented by formula (1C). At least one of Ar1-Ar5 is represented by general formula (2) or the like. In general formula (2), * represents a bond point to general formula (1). # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a photoelectric conversion element material and a photoelectric conversion element using the same, and more particularly to a photoelectric conversion element material that can be effectively used in an imaging device. Background Art

[0002] In recent years, the development of organic electronic devices using thin films formed of organic semiconductors is being promoted. For example, electric field light-emitting elements, solar cells, transistor elements, photoelectric conversion elements, etc. can be exemplified. In particular, among these, the development of organic electroluminescence (EL) elements, which are electric field light-emitting elements based on organic matter, is the most advanced, and while promoting their application in smart phones or televisions (TV), they continue to be developed with the goal of higher functionality.

[0003] In the photoelectric conversion element, the development and practical application of the element using the PN junction of inorganic semiconductors such as silicon have been promoted. The research on the high functionality of digital cameras and smartphone cameras, the research on the application in surveillance cameras, automotive sensors, etc., is being carried out. As the issues for coping with these various uses, high sensitivity and pixel miniaturization (high resolution) are listed. In the photoelectric conversion element using inorganic semiconductors, in order to obtain a color image, the method of configuring a color filter corresponding to red, green, and blue (RGB), which are the three primary colors of light, on the light receiving part of the photoelectric conversion element is mainly adopted. In the above method, since the RGB color filter is configured on a plane, there are problems in the utilization efficiency or resolution of the incident light (non-patent document 1, non-patent document 2).

[0004] As one of the solutions to the problem of such photoelectric conversion elements, the development of photoelectric conversion elements using organic semiconductors instead of inorganic semiconductors is being carried out (Non-Patent Document 1, Non-Patent Document 2). It utilizes the property of organic semiconductors that they can selectively absorb only light in a specific wavelength region with high sensitivity, and proposes to solve the problem of high sensitivity and high resolution by laminating photoelectric conversion elements obtained by using organic semiconductors corresponding to the three primary colors of light. In addition, an element obtained by laminating a photoelectric conversion element including an organic semiconductor and a photoelectric conversion element including an inorganic semiconductor has also been proposed (Non-Patent Document 3).

[0005] Here, the photoelectric conversion element using an organic semiconductor is an element constructed in the following manner, that is, a photoelectric conversion layer having a thin film containing an organic semiconductor is provided between two electrodes, and a hole blocking layer and / or an electron blocking layer is configured between the photoelectric conversion layer and the two electrodes as needed. In the photoelectric conversion element, excitons are generated by absorbing light having a desired wavelength using the photoelectric conversion layer, and then holes and electrons are generated by charge separation of the excitons. Thereafter, the light is converted into an electrical signal by migration of holes and electrons to each electrode. In order to promote the process, a method of applying a bias voltage between the two electrodes is generally used, but reducing the leakage current from the two electrodes generated by applying the bias voltage becomes one of the issues. In this case, it can be said that controlling the migration of holes or electrons in the photoelectric conversion element is the key to the manifestation of the characteristics of the photoelectric conversion element.

[0006] The organic semiconductors used in each layer of the photoelectric conversion element can be roughly divided into P-type organic semiconductors and N-type organic semiconductors. The P-type organic semiconductors are used as hole transport materials, and the N-type organic semiconductors are used as electron transport materials. In order to control the migration of holes and electrons in the photoelectric conversion element, various organic semiconductors with appropriate physical properties, such as hole mobility, electron mobility, energy value of the highest occupied molecular orbital (HOMO), and energy value of the lowest unoccupied molecular orbital (LUMO) have been developed. However, it cannot be said that they have sufficient characteristics and cannot be effectively used commercially.

[0007] Patent Document 1 proposes a device that uses quinacridone as a P-type organic semiconductor in a photoelectric conversion layer, uses subphthalocyanine chloride as an N-type organic semiconductor, and uses an indolocarbazole derivative in a first buffer layer disposed between the photoelectric conversion layer and an electrode.

[0008] Patent Document 2 proposes a method for using a photoelectric conversion layer An element using a chrysenodithiophene derivative as a P-type organic semiconductor and a fullerene or subphthalocyanine derivative as an N-type organic semiconductor.

[0009] Patent Documents 3 and 4 propose a device using a carbazole derivative in an electron blocking layer disposed between a photoelectric conversion layer and an electrode.

[0010] Patent Document 5 proposes a device using a pyrene derivative or a triphenylene derivative in an electron blocking layer disposed between a photoelectric conversion layer and an electrode.

[0011] Patent Document 6 proposes a device using a condensed aromatic compound such as benzothiophene dibenzothiophene or benzofuranyl dibenzofuran in a photoelectric conversion layer.

[0012] On the other hand, Patent Document 7 discloses an organic EL device using an indolocarbazole compound substituted with a nitrogen-containing six-membered ring structure.

[0013] Patent Document 8 discloses an organic EL device using an indolocarbazole compound substituted with a carbazole structure.

[0014] However, all of these are related to organic EL elements, and do not specifically show that they exhibit excellent characteristics as materials for photoelectric conversion elements.

[0015] Prior art literature

[0016] Patent Literature

[0017] Patent Document 1 Japanese Patent Application Publication No. 2018-85427

[0018] Patent Document 2: Japanese Patent Application Publication No. 2019-54228

[0019] Patent Document 3: Japanese Patent Application Publication No. 2011-228614

[0020] Patent Document 4: Japanese Patent Application Publication No. 2021-77888

[0021] Patent Document 5: Japanese Patent Application Publication No. 2015-153910

[0022] Patent document 6WO2021 / 090619

[0023] Patent Document 7WO2008 / 056746

[0024] Patent document 8WO2009 / 136595

[0025] Non-patent literature

[0026] Non-patent literature 1 NHK R&D No.132, pp.4-11 (2012.3)

[0027] Non-patent literature 2 NHK R&D No. 174, pp. 4-17 (2019.3)

[0028] Non-patent document 3 2019 Institute of Electrical and Electronics Engineers (IEEE) International Electron Devices Meeting (IEDM), pp. 16.6.1-16.6.4 (2019) Summary of the invention

[0029] Problems to be solved by the invention

[0030] Photoelectric conversion elements for imaging have become a subject of higher sensitivity and higher resolution in order to promote the high functionality of digital cameras and smartphone cameras, or their application in surveillance cameras, automotive sensors, etc. In view of this situation, the present invention aims to provide a material for achieving high sensitivity and high resolution of photoelectric conversion elements for imaging, and a photoelectric conversion element for imaging using the material.

[0031] Technical means to solve the problem

[0032] The inventors have made intensive research on the above-mentioned subject, and as a result, found that the process of generating holes and electrons by charge separation of excitons in the photoelectric conversion layer in the photoelectric conversion element and the process of migration of holes and electrons in the photoelectric conversion element can be efficiently promoted by using an indolecarbazole compound having a specific carbazole compound as a substituent, thereby completing the present invention. In particular, it has been newly found that by using an indolecarbazole compound having a specific carbazole structure as a substituent, the process of charge generation and charge migration in the photoelectric conversion element can be controlled, and the light-dark ratio related to the high sensitivity of the photoelectric conversion element can be improved.

[0033] The present invention is a material for a photoelectric conversion element for imaging, characterized by containing an indolocarbazole compound represented by the following general formula (1).

[0034] [Chemistry 1]

[0035]

[0036] In the general formula (1),

[0037] Ring B is condensed with an adjacent ring at an arbitrary position to form a six-membered ring represented by formula (1B).

[0038] Ring C is condensed with an adjacent ring at an arbitrary position to form a five-membered ring represented by formula (1C).

[0039] Ar 1 ~Ar 5each independently represents deuterium, cyano, halogen, nitro, an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 38 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an acyl group having 2 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 20 carbon atoms, an alkoxycarbonyloxy group having 2 to 20 carbon atoms, an alkylsulfonyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to 20 of these aromatic groups are linked, Ar 1 ~Ar 5 At least one of the following general formulas (2) to (8) is represented by any one of the following general formulas. 1 ~Ar 5 In the case of a group having a hydrogen atom, the hydrogen atom may be substituted with deuterium or a halogen.

[0040] a, b, and c represent the number of substitutions. a and b each independently represent an integer of 0 to 4, and c represents an integer of 0 to 2.

[0041] [Chemistry 2]

[0042]

[0043] In general formulae (2) to (8), * represents the bonding point with general formula (1),

[0044] L 1 ~L 4 It represents a direct bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two or three of these aromatic rings are linked.

[0045] Ar 6 ~Ar 16 each independently represents deuterium, cyano, a substituted or unsubstituted diarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two or three of these aromatic rings are linked,

[0046] d to k represent the number of substitutions, d, g, h, j, and k each independently represent an integer of 0 to 4, and e, f, and i each independently represent an integer of 0 to 3.

[0047] The general formula (1) is preferably represented by any one of the following general formulas (9) to (13). That is, the indolecarbazole compound represented by the general formula (1) is preferably represented by the following general formula (9), is also preferably represented by the following general formula (10), is also preferably represented by the following general formula (11), is also preferably represented by the following general formula (12), and is also preferably represented by the following general formula (13). Regarding the general formula (1), as its form, it can be appropriately selected from the indolecarbazole compounds represented by the general formulas (9) to (13). For example, the general formula (1) can be represented by any one of the following general formulas (9) to (11) and (13), and can also be represented by any one of the following general formulas (10), (11) and (13), and can also be represented by any one of the following general formulas (9), (11) to (13). Furthermore, in the general formulas (9) to (13), Ar 1 ~Ar 5 , and a to c are the same as those described in the above general formula (1).

[0048] [Chemistry 3]

[0049]

[0050]

[0051] In addition, the general formulae (5) to (8) are more preferably represented by the following general formulae (5A) to (8C). 1 ~L 4 ,Ar 12 ~Ar 16 , h to k are the same as those described in the general formulae (5) to (8).

[0052] [Chemistry 4]

[0053]

[0054] [Chemistry 5]

[0055]

[0056] For Ar in the general formula (1) 1 or Ar 5 At least one of the above is preferably represented by any one of the general formulae (2) to (8). More preferably, Ar 1 or Ar 5 At least one of the above general formulae (5A) to (8C) is represented by any one of the above general formulae (2) to (8). 1 , and L 3A single bond is more preferred.

[0057] In the photoelectric conversion element material, the energy level of the highest occupied molecular orbital (HOMO) obtained by structure optimization calculation based on density functional calculation B3LYP / 6-31G(d) is preferably less than -4.5 eV. In addition, the energy level of the lowest unoccupied molecular orbital (LUMO) is preferably greater than -2.5 eV.

[0058] The photoelectric conversion element material preferably has a 1×10 -6 cm 2 The hole mobility is 1.1777 W / Vs or more. In addition, the photoelectric conversion element material is preferably amorphous.

[0059] The photoelectric conversion element material can be used as a hole transport material.

[0060] In addition, the present invention is a photoelectric conversion element for imaging, which has a photoelectric conversion layer and an electron blocking layer between two electrodes, and the photoelectric conversion element for imaging is characterized in that at least one of the photoelectric conversion layer and the electron blocking layer contains the photoelectric conversion element material.

[0061] The photoelectric conversion element of the present invention may contain the above-mentioned photoelectric conversion element material in the electron blocking layer, and may contain an electron transporting material such as a fullerene derivative in the photoelectric conversion layer.

[0062] Effects of the Invention

[0063] It is believed that by using the photoelectric conversion element material for imaging of the present invention, it is possible to achieve appropriate migration of holes or electrons in the photoelectric conversion element for imaging, thereby reducing leakage current generated by applying a bias voltage when converting light into electrical energy, and as a result, a photoelectric conversion element with a low dark current value and a high light-dark ratio can be obtained. Therefore, the material of the present invention is effectively used as a photoelectric conversion element material for a photoelectric conversion film laminated imaging device. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] [ Figure 1 ] is a cross-sectional schematic diagram showing a structural example of the photoelectric conversion element used in the present invention. DETAILED DESCRIPTION

[0065] The imaging photoelectric conversion element of the present invention is a photoelectric conversion element having at least one organic layer between two electrodes and converting light into electrical energy. The organic layer contains a photoelectric conversion element material for imaging containing a compound represented by the general formula (1). Specifically, in an imaging photoelectric conversion element having a photoelectric conversion layer and an electron blocking layer between two electrodes, at least one of the photoelectric conversion layer and the electron blocking layer contains a photoelectric conversion element material represented by the general formula (1). Hereinafter, the imaging photoelectric conversion element material containing a compound represented by the general formula (1) is referred to as a photoelectric conversion element material. In addition, it is sometimes referred to as the material of the present invention or the compound represented by the general formula (1).

[0066] The compound represented by the general formula (1) is described below.

[0067] In the general formula (1), ring B is condensed with an adjacent ring at any position to represent a six-membered ring represented by the formula (1B). Ring C is condensed with an adjacent ring at any position to represent a five-membered ring represented by the formula (1C).

[0068] As a more preferred form of the general formula (1), it is represented by the general formula (9) to the general formula (13). That is, the indolecarbazole compound represented by the general formula (1) is preferably represented by the general formula (9), and is also preferably represented by the following general formula (10), is also preferably represented by the following general formula (11), is also preferably represented by the following general formula (12), and is also preferably represented by the following general formula (13). Regarding the general formula (1), as its form, it can be appropriately selected from the indolecarbazole compounds represented by the general formulas (9) to (13). For example, the general formula (1) can be represented by any one of the following general formulas (9) to (11) and (13), and can also be represented by any one of the following general formulas (10), (11) and (13), and can also be represented by any one of the following general formulas (9), (11) to (13).

[0069] In the general formulas (9) to (13), Ar 1 ~Ar 5 , and a to c are the same as those described in the above general formula (1).

[0070] In the general formula (1), Ar 1 ~Ar 5 At least one of the above general formulae (2) to (8) is represented by any one of the general formulae, but preferably Ar 1 or Ar 5 At least one of the above is represented by any one of the general formulae (2) to (8), and more preferably is represented by any one of the general formulae (2), (3), (5) and (8).

[0071] In the general formula (1), Ar 1 ~Ar 5 At least one of the above is represented by any one of the general formulae (2) to (8), wherein the general formulae (5) to (8) are preferably represented by any one selected from the group consisting of the general formulae (5A), (5B), (5C), (6A), (6B), (6C), (7A), (7B), (7C), (8A), (8B), and (8C). Among them, it is more preferably represented by any one of the general formulae (5A), (5B), (5C), (8A), (8B), or (8C).

[0072] In the general formulae (5A) to (8C), L 1 ~L 4 ,Ar 12 ~Ar 16 , h to k are the same as those described in the general formulae (5) to (8).

[0073] Ar 1 ~Ar 5 each independently represents deuterium, cyano, halogen, nitro, an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 38 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an acyl group having 2 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 20 carbon atoms, an alkoxycarbonyloxy group having 2 to 20 carbon atoms, an alkylsulfonyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to 20 of these aromatic groups are linked, Ar 1 ~Ar 5 At least one of the above-mentioned general formulae (2) to (8) is represented by any one of the general formulae (2) to (8). More preferably, it is a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 6 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which 2 to 20 of these aromatic groups are linked. Furthermore, when these groups have hydrogen atoms, the hydrogen atoms may be substituted by deuterium or halogen.

[0074] The alkyl group having 1 to 20 carbon atoms may be any of a linear, branched, or cyclic alkyl group, and is preferably a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms. Specific examples thereof include linear saturated hydrocarbon groups such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-octyl, n-dodecyl, n-tetradecyl, and n-octadecyl, branched saturated hydrocarbon groups such as isopropyl, isobutyl, neopentyl, 2-ethylhexyl, and 2-hexyloctyl, and saturated alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cyclooctyl, and 4-butylcyclohexyl.

[0075] Specific examples of aralkyl groups having 7 to 38 carbon atoms include benzyl, phenethyl, phenylpropyl, phenylbutyl, naphthylmethyl, triphenylmethyl, etc. Specific examples of alkenyl groups having 2 to 20 carbon atoms include ethylene, propylene, butylene, pentenyl, cyclopentenyl, hexenyl, cyclohexenyl, octenyl, etc. Specific examples of alkynyl groups having 2 to 20 carbon atoms include ethynyl, propynyl, butynyl, pentynyl, etc. Specific examples of acyl groups having 2 to 20 carbon atoms include formyl, acetyl, propionyl, benzoyl, etc. Specific examples of alkoxy groups having 1 to 20 carbon atoms include methoxy, ethoxy, propoxy, butoxy, etc.

[0076] In Ar 1 ~Ar 5 When it represents a linked aromatic group, the number of linked groups is preferably 2 to 12, and more preferably 2 to 6. 1 ~Ar 5 The number of linkages when indicating the linked aromatic groups includes two carbazole (CBZ) groups described in formulae (2) to (8).

[0077] a, b, and c represent the number of substitutions, and a and b each independently represent an integer of 0 to 4, more preferably 0 to 2, and more preferably 0 to 1. c represents an integer of 0 to 2, more preferably 0 to 1, and more preferably 0.

[0078] L 1 ~L 4 It represents a direct bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two or three of these aromatic rings are linked, and more preferably represents a direct bond.

[0079] Ar 6 ~Ar 16Each independently represents deuterium, cyano, a substituted or unsubstituted diarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two or three of these aromatic rings are linked, d to k represent the number of substitutions, and d, g, h, j, and k each independently represent an integer of 0 to 4, preferably 0 to 2, and more preferably 0 to 1. e, f, and i each independently represent an integer of 0 to 3, preferably 0 to 2, and more preferably 0.

[0080] Specific examples of the aryl group of the aromatic amino group include phenyl, biphenyl, terphenyl, quaterphenyl, naphthyl, phenanthryl, anthracenyl, triphenylene, pyrenyl, fluorenyl, and spirobifluorenyl, among which phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, fluorenyl, and triphenylene are preferred.

[0081] Specific examples of the heteroaryl group of the aromatic amino group include pyrrole, pyrrolopyrrole, indole, pyrroloindole, benzindole, naphthopyrrole, isoindole, pyrroloisoindole, benzisoindole, naphthoisopyrrole, carbazole, phenylcarbazole, biphenylcarbazole, benzocarbazole, indoloindole, carbazolecarbazole, benzofuranocarbazole, benzothienylcarbazole, carboline, thiophene, benzothiophene, naphthothiophene, dibenzothiophene, benzothienylnaphthalene, benzothienylbenzothiophene, benzothienyldibenzothiophene, A group obtained by removing one hydrogen atom from dinaphthothiophene, dinaphthothienothiophene, naphthylbenzothiophene, furan, benzofuran, naphthioran, dibenzofuran, benzofuranonaphthalene, benzofuranbenzofuran, benzofurandibenzofuran, dinaphthofuran, dinaphthofuranandofuran, naphthylbenzofuran, pyridine, pyrimidine, triazine, quinoline, isoquinoline, quinazoline, quinoxaline, etc., and among these, a group derived from dibenzofuran, dibenzothiophene, carbazole, benzofurancarbazole or benzothienylcarbazole is more preferred.

[0082] Examples of the aromatic hydrocarbon group having 6 to 18 carbon atoms include groups obtained by removing one hydrogen atom from known aromatic hydrocarbons. Examples of the aromatic hydrocarbon include monocyclic aromatic hydrocarbons such as benzene, bicyclic aromatic hydrocarbons such as naphthalene, tricyclic aromatic hydrocarbons such as indacene, biphenylene, phenanthracene, anthracene, phenanthrene, and fluorene, fluoranthene, acephenanthrylene, aceanthrylene, triphenylene, pyrene, A group derived from tetracyclic aromatic hydrocarbons such as tetraphene, tetraphenylene, and pleiadene. More preferably, a group derived from benzene, naphthalene, anthracene, triphenylene, or pyrene.

[0083] Examples of the aromatic heterocyclic group having 3 to 18 carbon atoms include groups obtained by removing one hydrogen atom from an aromatic heterocyclic group. Examples of the aromatic heterocyclic group include pyrrole, pyrrolopyrrole, indole, pyrroloindole, benzindole, naphthopyrrole, isoindole, pyrroloisoindole, benzisoindole, naphthoisopyrrole, carbazole, benzocarbazole, indoloindole, carbazolecarbazole, indolicorbazole, and a nitrogen-containing aromatic compound having a pyrrole ring such as carboline; thiophene, benzothiophene, naphthothiophene, dibenzothiophene, benzothiophene naphthalene, benzothiophene, benzothiophene dibenzothiophene, dinaphthothiophene As examples, the radicals derived from sulfur-containing aromatic compounds having a thiophene ring such as dinaphthothienothiophene, naphthobenzothiophene, and benzothiophenecarbazole, furan, benzofuran, naphthofuran, dibenzofuran, benzofuranonaphthalene, benzofuranobenzofuran, benzofuranodibenzofuran, dinaphthofuran, dinaphthofuranofuran, naphthobenzofuran, benzofuranocarbazole, oxygen-containing aromatic compounds having a furan ring such as pyridine, pyrimidine, triazine, quinoline, isoquinoline, quinazoline, and quinoxaline are shown. More preferably, the radicals derived from dibenzofuran, dibenzothiophene, carbazole, benzothienyldibenzothiophene, benzofuranodibenzofuran, indolecarbazole, benzofuranocarbazole, or benzothienylcarbazole are used.

[0084] In this specification, a linked aromatic group refers to an aromatic group formed by linking two or more aromatic groups through a single bond. These linked aromatic groups may be straight-chain or branched. The linking position when the benzene rings are linked to each other may be any one of ortho, meta, or para, preferably para or meta. The aromatic group may be an aromatic hydrocarbon group or an aromatic heterocyclic group, and a plurality of aromatic groups may be the same or different.

[0085] Yu Ar 1 ~Ar 16 In the case of an aromatic hydrocarbon group, an aromatic heterocyclic group or a linked aromatic group, it may have a substituent, and examples of the substituent include deuterium, an alkyl group having 1 to 20 carbon atoms, a cyano group, and a silyl group. The alkyl group having 1 to 20 carbon atoms may be any of a linear, branched, or cyclic alkyl group, and preferably deuterium, a linear, branched, or cyclic alkyl group having 1 to 10 carbon atoms, or a cyano group. As specific examples thereof, examples include: a linear saturated hydrocarbon group such as a methyl group, an ethyl group, a n-propyl group, a n-butyl group, a n-pentyl group, a n-hexyl group, a n-octyl group, a n-dodecyl group, a n-tetradecyl group, and a n-octadecyl group; a branched saturated hydrocarbon group such as an isopropyl group, an isobutyl group, a neopentyl group, a 2-ethylhexyl group, and a 2-hexyloctyl group; and a saturated alicyclic hydrocarbon group such as a cyclopentyl group, a cyclohexyl group, a cyclooctyl group, a 4-butylcyclohexyl group, and a 4-dodecylcyclohexyl group.

[0086] More preferable specific examples of the compound represented by the general formula (1) as the photoelectric conversion element material of the present invention are shown below, but the present invention is not limited to these.

[0087] [Chemistry 6]

[0088]

[0089] [Chemistry 7]

[0090]

[0091] [Chemistry 8]

[0092]

[0093] [Chemistry 9]

[0094]

[0095] [Chemistry 10]

[0096]

[0097] [Chemistry 11]

[0098]

[0099] [Chemistry 12]

[0100]

[0101] [Chemistry 13]

[0102]

[0103] [Chemistry 14]

[0104]

[0105] [Chemistry 15]

[0106]

[0107] [Chemistry 16]

[0108]

[0109] [Chemistry 17]

[0110]

[0111] [Chemistry 18]

[0112]

[0113] [Chemistry 19]

[0114]

[0115] [Chemistry 20]

[0116]

[0117] [Chemistry 21]

[0118]

[0119] [Chemistry 22]

[0120]

[0121] [Chemistry 23]

[0122]

[0123] [Chemistry 24]

[0124]

[0125] [Chemistry 25]

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[0127] [Chemistry 26]

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[0129] [Chemistry 27]

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[0131] [Chemistry 28]

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[0133] [Chemistry 29]

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[0135] [Chemistry 30]

[0136]

[0137] [Chemistry 31]

[0138]

[0139] The compound represented by the general formula (1) of the present invention can be obtained by synthesizing it by a method based on various organic synthesis reactions established in the field of organic synthetic chemistry including coupling reactions such as Suzuki coupling, Stille coupling, Grignard coupling, Ullmann coupling, Buchwald-Hartwig reaction, and Heck reaction using commercially available reagents as raw materials, and then purifying it by a known method such as recrystallization, column chromatography, and sublimation purification, but the method is not limited to the above methods.

[0140] Regarding the material for the photoelectric conversion element of the present invention, the energy level of the highest occupied molecular orbital (HOMO) obtained by the structure optimization calculation based on the density functional calculation B3LYP / 6-31G(d) is preferably below -4.5 eV, more preferably in the range of -6.0 eV to -4.5 eV, and further preferably in the range of greater than -5.0 eV and less than -4.5 eV.

[0141] Regarding the material for the photoelectric conversion element of the present invention, the energy level of the lowest unoccupied molecular orbital (LUMO) obtained by the structure optimization calculation based on the density functional calculation B3LYP / 6-31G(d) is preferably above -2.5 eV, more preferably in the range of -2.5 eV to -0.5 eV, and further preferably in the range of greater than -1.5 eV and less than -0.5 eV.

[0142] Regarding the photoelectric conversion element material of the present invention, the difference (absolute value) between the HOMO level and the LUMO level is preferably in the range of 2.0 eV to 5.0 eV, more preferably in the range of 2.5 eV to 4.5 eV, and most preferably in the range of 3.5 eV to 4.5 eV.

[0143] The photoelectric conversion element material of the present invention may have a 1×10 -6 cm 2 / Vs or more, and preferably has a hole mobility of 1×10 -6 cm 2 / Vs~1cm 2 / Vs, more preferably 1×10 -5 cm 2 / Vs~1×10 -1 cm 2The hole mobility can be evaluated by a known method such as a method based on a field effect transistor (FET) type transistor element, a method based on a time-of-flight method, or a space charge limited current (SCLC) method.

[0144] The photoelectric conversion element material of the present invention is preferably amorphous. The amorphous state can be confirmed by various methods, for example, by not detecting a peak by X-ray diffraction (XRD) or by not detecting an endothermic peak by differential scanning calorimetry (DSC).

[0145] Next, an imaging photoelectric conversion element using the photoelectric conversion element material of the present invention will be described, but the structure of the imaging photoelectric conversion element of the present invention is not limited thereto.

[0146] Figure 1 1 is a cross-sectional view schematically showing a structural example of the imaging photoelectric conversion element of the present invention, wherein 1 represents an electrode, 2 represents a hole blocking layer, 3 represents a photoelectric conversion layer, 4 represents an electron blocking layer, 5 represents an electrode, and 6 represents a substrate. Figure 1 Inverted structure, that is, 1 is an electrode, 2 is an electron blocking layer, 3 is a photoelectric conversion layer, 4 is a hole blocking layer, 5 is an electrode, and 6 is a substrate. Figure 1 The structure can add or omit layers as needed.

[0147] -electrode-

[0148] The electrode used in the imaging photoelectric conversion element using the imaging photoelectric conversion element material of the present invention has the function of trapping holes and electrons generated in the photoelectric conversion layer. In addition, it is also necessary to have the function of allowing light to enter the photoelectric conversion layer. Therefore, it is ideal that at least one of the two electrodes is transparent or translucent. In addition, the material used as the electrode is not particularly limited as long as it is a conductive material, and examples thereof include: indium tin oxide (ITO), indium zinc oxide (IZO), SnO2, antimony doped tin oxide (ATO), ZnO, aluminum doped zinc oxide (AZO), gallium doped zinc oxide (GZO), TiO2, and conductive transparent materials such as fluorine doped tin oxide (FTO), metals such as gold, silver, platinum, chromium, aluminum, iron, cobalt, nickel, and tungsten, inorganic conductive materials such as copper iodide and copper sulfide, conductive polymers such as polythiophene, polypyrrole, and polyaniline, etc. Regarding these materials, multiple types can also be mixed and used as needed. In addition, two or more layers can also be stacked.

[0149] -Photoelectric conversion layer-

[0150] The photoelectric conversion layer is a layer that generates holes and electrons by charge separation of excitons generated by incident light. It can be formed by a single photoelectric conversion material, or it can be formed by combining with a P-type organic semiconductor material as a hole transport material, or an N-type organic semiconductor material as an electron transport material. In addition, two or more P-type organic semiconductors can be used, and two or more N-type organic semiconductors can also be used. It is ideal that one or more of these P-type organic semiconductors and / or N-type semiconductors use a pigment material that has the function of absorbing light of a desired wavelength in the visible region. As a P-type organic semiconductor material for a hole transport material, a compound represented by the general formula (1) of the present invention can be used.

[0151] As a P-type organic semiconductor material, any material having hole transport properties may be used, and preferably a material represented by general formula (1) is used, but other P-type organic semiconductor materials may also be used. In addition, two or more materials represented by general formula (1) may be used in combination. Furthermore, a compound represented by general formula (1) and other P-type organic semiconductor materials may also be used in combination.

[0152] As other P-type organic semiconductor materials, any material having hole transport properties may be used, for example, naphthalene, anthracene, phenanthrene, pyrene, Compounds having condensed polycyclic aromatic groups such as tetraphenyl, triphenylene, perylene, fluoranthene, fluorene, and indene; compounds having π-excess aromatic groups such as cyclopentadiene derivatives, furan derivatives, thiophene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, dinaphthothiophene derivatives, indole derivatives, pyrazoline derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, carbazole derivatives, indolecarbazole, etc.; aromatic amine derivatives, styrylamine derivatives, benzidine derivatives, porphyrin derivatives, phthalocyanine derivatives, and quinacridone derivatives.

[0153] In addition, as polymeric P-type organic semiconductor materials, there can be exemplified: polyphenylene vinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinylcarbazole derivatives, polythiophene derivatives. In addition, two or more selected from the compounds represented by general formula (1), P-type organic semiconductor materials or polymeric P-type organic semiconductor materials can also be used in combination.

[0154] As the N-type organic semiconductor material, any material having electron transport properties may be used, for example, naphthalenetetracarboxylic acid diimide or perylenetetracarboxylic acid diimide, fullerenes, imidazole, thiazole, thiadiazole, oxazole, oxadiazole, triazole and the like azole derivatives, etc. In addition, two or more selected from the N-type organic semiconductor materials may be used in combination.

[0155] -Electron blocking layer-

[0156] The electron blocking layer is provided to suppress the dark current generated by injecting electrons from one of the electrodes into the photoelectric conversion layer when a bias voltage is applied between the two electrodes. In addition, it also has a hole transport function of transporting holes generated by charge separation in the photoelectric conversion layer to the electrode, and a single layer or multiple layers can be configured as needed. A P-type organic semiconductor material as a hole transport material can be used in the electron blocking layer. As a P-type organic semiconductor material, any material having hole transport properties can be used, and it is more preferred to use a compound represented by the general formula (1), and other P-type organic semiconductor materials can also be used. In addition, the compound represented by the general formula (1) and other P-type organic semiconductor materials can also be used in combination. As other P-type organic semiconductor materials, any material having hole transport properties can be used, for example, naphthalene, anthracene, phenanthrene, pyrene, Compounds having condensed polycyclic aromatic groups such as condensed tetraphenyl, triphenylene, perylene, fluoranthene, fluorene, and indene; compounds having π-excess aromatic groups such as cyclopentadiene derivatives, furan derivatives, thiophene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, dinaphthothiophene derivatives, indole derivatives, pyrazoline derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, and carbazole derivatives; aromatic amine derivatives, styrylamine derivatives, benzidine derivatives, porphyrin derivatives, phthalocyanine derivatives, and quinacridone derivatives.

[0157] In addition, as polymeric P-type organic semiconductor materials, polyphenylene vinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinyl carbazole derivatives, and polythiophene derivatives can be exemplified. In addition, two or more selected from the compounds represented by the general formula (1) of the present invention, P-type organic semiconductor materials, or polymeric P-type organic semiconductor materials can also be used in combination.

[0158] -Hole blocking layer-

[0159] The hole blocking layer is provided to suppress the dark current generated by the injection of holes from one of the electrodes into the photoelectric conversion layer when a bias voltage is applied between the two electrodes. In addition, it also has the function of electron transport, which is to transport electrons generated by charge separation in the photoelectric conversion layer to the electrode, and can be configured as a single layer or multiple layers as needed. An N-type organic semiconductor with electron transport properties can be used in the hole blocking layer.

[0160] As the N-type organic semiconductor material, any material having electron transport properties may be used, for example, polycyclic aromatic polycarboxylic acid anhydrides such as naphthalenetetracarboxylic acid diimide or perylenetetracarboxylic acid diimide or imides thereof, fullerenes such as C60 or C70, azole derivatives such as imidazole, thiazole, thiadiazole, oxazole, oxadiazole, triazole, tris(8-hydroxyquinoline)aluminum(III) derivatives, phosphine oxide derivatives, nitrosubstituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimide, fluorenyl methane derivatives, anthraquinone dimethane and anthrone derivatives, bipyridine derivatives, quinoline derivatives, indolocarbazole derivatives, etc. In addition, two or more of these N-type organic semiconductor materials may be used in combination.

[0161] The hydrogen in the material of the present invention may be deuterium. That is, in addition to the hydrogen on the aromatic ring in the general formula (1) or the general formulas (2) to (8), part or all of the hydrogen in the substituent may be deuterium.

[0162] Furthermore, part or all of the hydrogen contained in the compound used as the N-type organic semiconductor material and the P-type organic semiconductor material may be deuterium.

[0163] The film-forming method of each layer when producing the imaging photoelectric conversion element of the present invention is not particularly limited, and the element can be produced by any of a dry process and a wet process.

[0164] The organic layer containing the photoelectric conversion element material of the present invention may be formed into a plurality of layers as necessary.

[0165] Example

[0166] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0167] Calculation Example

[0168] Calculation of HOMO and LUMO

[0169] The HOMO, LUMO, and energy difference between HOMO and LUMO of the compound A02, compound A32, compound B05, compound B53, compound C01, compound C19, compound C23, compound C59, compound D10, compound D25, compound E09, and compound F02 were calculated. Furthermore, the calculation was performed using a calculation based on density functional theory (DFT: Density Functional Theory), using Gaussian as a calculation program, and by a structure optimization calculation based on density functional theory calculation B3LYP / 6-31G (d). The results are shown in Table 1. It can be said that the photoelectric conversion element materials for imaging of the present invention all have more preferred HOMO and LUMO values.

[0170] The HOMO, LUMO, and energy difference between HOMO and LUMO of H1, H2, H3, and H4 as comparative compounds were calculated by the same method.

[0171] [Chemistry 32]

[0172]

[0173] [Table 1]

[0174] Compound HOMO[eV] LUMO[eV] Energy difference [eV] A02 -4.9 -1.1 3.9 A32 -4.9 -0.9 4.1 B05 -4.8 -1.1 3.7 B53 -4.8 -0.8 4.0 C01 -4.7 -1.0 3.7 C19 -4.7 -1.2 3.5 C23 -5.0 -1.2 3.8 C59 -4.9 -1.1 3.8 D10 -4.7 -1.0 3.7 D25 -4.8 -1.0 3.8 E09 -4.8 -1.0 3.9 F02 -4.8 -1.1 3.8 H1 -5.3 -1.9 3.4 H2 -5.0 -0.9 4.1 H3 -5.1 -0.8 4.2 H4 -4.9 -0.7 4.2

[0175] The following is a synthesis example of compound A02 as a representative example. Other compounds were synthesized by similar methods.

[0176] Synthesis Example 1 (Synthesis of Intermediate R3)

[0177] [Chemistry 33]

[0178]

[0179] R1 (27.1 mmol), R2 (28.4 mmol), copper iodide (0.5 mmol), tripotassium phosphate (81.3 mmol) were added to a 500 ml three-necked flask that had been denitrogenated, and 100 ml of dehydrated dioxane was added thereto, followed by stirring at 120°C for 3 hours. After cooling to room temperature, the inorganic matter was removed by filtration, 200 ml of water and 200 ml of dichloromethane were added to the filtrate, and the filtrate was transferred to a separatory funnel and separated into an organic layer and an aqueous layer. The organic layer was washed three times with 200 ml of water, and the obtained organic layer was dehydrated with magnesium sulfate and then concentrated under reduced pressure. The obtained residue was refined by column chromatography to obtain R3 (light yellow solid).

[0180] Synthesis Example 2 (Synthesis of Intermediate R5)

[0181] [Chemistry 34]

[0182]

[0183] R4 (19.5 mmol), R3 (21.5 mmol) synthesized in Synthesis Example 1, copper iodide (2.0 mmol), potassium carbonate (39.0 mmol) were added to a 500 ml three-necked flask that was denitrogenated, and 50 ml of dimethyl imidazolidinone was added thereto, and stirred at 180 ° C for 8 hours. After cooling to room temperature, the inorganic matter was removed by filtration, 200 ml of water and 200 ml of dichloromethane were added to the filtrate, and the filtrate was transferred to a separatory funnel and separated into an organic layer and an aqueous layer. The organic layer was washed three times with 200 ml of water, and the obtained organic layer was dehydrated with magnesium sulfate and concentrated under reduced pressure. The obtained residue was refined by column chromatography to obtain R5 (light yellow solid).

[0184] Synthesis Example 3 (Synthesis of A02)

[0185] [Chemistry 35]

[0186]

[0187] R5 (6.8 mmol), R6 (101.5 mmol), copper powder (20.3 mmol), and potassium carbonate (33.8 mmol) synthesized in Synthesis Example 2 were placed in a 500 ml three-necked flask that had been denitrogenated and replaced, and stirred at 180°C for 8 hours. After cooling to room temperature, the inorganic matter was removed by filtration, and 200 ml of water and 200 ml of dichloromethane were added to the filtrate, and the filtrate was transferred to a separatory funnel to separate the organic layer and the aqueous layer. The organic layer was washed three times with 200 ml of water, and the obtained organic layer was dehydrated with magnesium sulfate and then concentrated under reduced pressure. The obtained residue was purified by column chromatography to obtain A02 (colorless solid). The obtained solid was evaluated by XRD method, but no peak was detected, so it was known that the compound was amorphous. (APCI-TOFMS, m / z739[M+H] + )

[0188] Physical property evaluation example

[0189] Compound A02 was formed as an organic layer by vacuum deposition at a film thickness of about 3 μm on a glass substrate on which a transparent electrode including ITO with a film thickness of 110 nm was formed. Subsequently, an element formed with aluminum (Al) with a thickness of 70 nm was used as an electrode, and the charge mobility was measured by the time-of-flight method. The hole mobility was 2.0×10 -4 cm 2 / Vs.

[0190] The hole mobility was evaluated in the same manner except that compound A02 was replaced with A32, B01, B05, B53, C01, C19, C59, D05, D10, D25, E09, F02, H1, H2, H3 or H4. The results are shown in Table 2.

[0191] [Table 2]

[0192] Compound <![CDATA[Hole mobility [cm 2 / Vs]]]> Compound <![CDATA[Hole mobility [cm 2 / Vs]]]> A02 <![CDATA[2.0×10 -4 ]]> D05 <![CDATA[4.2×10 -5 ]]> A32 <![CDATA[2.5×10 -4 ]]> D10 <![CDATA[7.3×10 -5 ]]> B01 <![CDATA[1.3×10 -4 ]]> D25 <![CDATA[5.2×10 -5 ]]> B05 <![CDATA[5.1×10 -5 ]]> E09 <![CDATA[8.5×10 -5 ]]> B53 <![CDATA[6.7×10 -5 ]]> F02 <![CDATA[2.0×10 -5 ]]> C01 <![CDATA[9.2×10 -5 ]]> H1 <![CDATA[4.0×10 -5 ]]> C19 <![CDATA[3.1×10 -4 ]]> H2 <![CDATA[3.0×10 -5 ]]> C23 <![CDATA[7.5×10 -4 ]]> H3 <![CDATA[1.0×10 -4 ]]> C59 <![CDATA[1.2×10 -4 ]]> H4 <![CDATA[1.2×10 -5 ]]>

[0193] Example 1

[0194] On the ITO film with a thickness of 70 nm formed on the glass substrate, the vacuum degree was 4.0×10 -5 Pa formed a film of compound A02 with a thickness of 100 nm as an electron blocking layer. Next, a quinacridone film was formed with a thickness of 100 nm as a photoelectric conversion layer. Finally, aluminum was formed with a thickness of 70 nm as an electrode to form a photoelectric conversion element for imaging.

[0195] When a voltage of 2V is applied to ITO and aluminum electrodes, the current in the dark is 4.1×10 -12 A / cm 2In addition, a voltage of 2 V was applied to the ITO electrode (transparent conductive glass) side, and the current when irradiated with light of wavelength 500 nm was 4.0×10 -6 A / cm 2 When a 2V voltage is applied to the transparent conductive glass side, the light-dark ratio is 9.8×10 5 .

[0196] Comparative Example 1

[0197] On an electrode including 70 nm thick ITO formed on a glass substrate, a vacuum degree of 4.0×10 -5 Pa formed a 100nm thick film of compound H1 as an electron blocking layer. Next, quinacridone was formed into a 100nm thick film as a photoelectric conversion layer. Finally, aluminum was formed into a 70nm thick film as an electrode to make a photoelectric conversion element for imaging. When a voltage of 2V was applied to ITO and aluminum as electrodes, the current in the dark was 6.7×10 -12 A / cm 2 In addition, a voltage of 2 V was applied to the ITO electrode side, and the current when irradiated with light of wavelength 500 nm was 2.2×10 -6 A / cm 2 When a 2V voltage is applied to the transparent conductive glass side, the light-dark ratio is 3.3×10 5 .

[0198] Table 3 shows the results when Compound A02 (Example 1) was used as the electron blocking layer and when Compound H1 (Comparative Example 1) was used.

[0199] [Table 3]

[0200]

[0201] Example 2

[0202] On an electrode including 70 nm thick ITO formed on a glass substrate, a vacuum degree of 4.0×10 -5 Pa deposited compound A02 with a thickness of 10nm as an electron blocking layer. Then, as a photoelectric conversion layer, 2Ph-BTBT, F6-SubPc-OC6F5, and fullerene (C60) were co-deposited at a deposition rate ratio of 4:4:2 to form a 200nm film. Next, dpy-NDI was deposited at a thickness of 10nm to form a hole blocking layer. Finally, aluminum was deposited with a thickness of 70nm as an electrode to make a photoelectric conversion element. When a voltage of 2.6V was applied using ITO and aluminum as electrodes, the current in the dark (dark current) was 4.9×10 -10 A / cm 2In addition, when a voltage of 2.6 V was applied and the ITO electrode side was irradiated with light from a height of 10 cm by an LED with a wavelength of 500 nm and 1.6 μW, the current (bright current) was 3.1×10 -7 A / cm 2 The light-dark ratio when 2.6V voltage is applied is 6.3×10 2 These results are shown in Table 4.

[0203] Embodiments 3 to 8

[0204] A photoelectric conversion element was prepared in the same manner as in Example 2 except that the compound shown in Table 4 was used as the electron blocking layer.

[0205] Comparative Examples 2 to 4

[0206] A photoelectric conversion element was prepared in the same manner as in Example 2 except that the compound shown in Table 4 was used as the electron blocking layer.

[0207] Table 4 shows the results of Examples 3 to 8 and Comparative Examples 2 to 4.

[0208] The compounds used in Examples and Comparative Examples are shown below.

[0209] [Chemistry 36]

[0210]

[0211] [Table 4]

[0212]

[0213] From these results, it is clear that the compound of the present invention is excellent in the light-dark ratio and is effectively used as a material for a photoelectric conversion element for imaging.

[0214] Explanation of symbols

[0215] 1: Electrode

[0216] 2: Hole blocking layer

[0217] 3: Photoelectric conversion layer

[0218] 4: Electron blocking layer

[0219] 5: Electrode

[0220] 6:Substrate

Claims

1. A photoelectric conversion element material for imaging, characterized in that: An indolocarbazole compound represented by the following general formula (1) is included, [Chemistry 1] In the general formula (1), Ring B is condensed with an adjacent ring at any position and represents a six-membered ring represented by formula (1B); Ring C is condensed with an adjacent ring at any position and represents a five-membered ring represented by formula (1C); Ar 1 ~Ar 5 each independently represents deuterium, cyano, halogen, nitro, an alkyl group having 1 to 20 carbon atoms, an aralkyl group having 7 to 38 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, an alkynyl group having 2 to 20 carbon atoms, an acyl group having 2 to 20 carbon atoms, an acyloxy group having 2 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an alkoxycarbonyl group having 2 to 20 carbon atoms, an alkoxycarbonyloxy group having 2 to 20 carbon atoms, an alkylsulfonyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two to 20 of these aromatic groups are linked, Ar 1 ~Ar 5 At least one of the following general formulas (2) to (8) is represented by any one of the following general formulas; and in Ar 1 ~Ar 5 In the case of a group having a hydrogen atom, the hydrogen atom may be substituted by deuterium or halogen; a, b, and c represent the number of substitutions, a and b each independently represent an integer of 0 to 4, and c represents an integer of 0 to 2; [Chemistry 2] In general formulae (2) to (8), * represents the bonding point with general formula (1), L 1 ~L 4 represents a direct bond, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two or three of these aromatic rings are linked; Ar 6 ~Ar 16 each independently represents deuterium, cyano, a substituted or unsubstituted diarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 36 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 18 carbon atoms, or a substituted or unsubstituted linked aromatic group in which two or three of these aromatic rings are linked, d to k represent the number of substitutions, d, g, h, j, and k each independently represent an integer of 0 to 4, and e, f, and i each independently represent an integer of 0 to 3.

2. The material for a photoelectric conversion element for imaging according to claim 1, wherein The general formula (1) is represented by any one of the following general formulas (9) to (13): [Chemistry 3] In the general formulas (9) to (13), Ar 1 ~Ar 5 , and a to c are the same as those described in the above general formula (1).

3. The material for a photoelectric conversion element for imaging according to claim 2, wherein: The general formula (1) is represented by any one of the general formulas (9) to (11) and (13).

4. The material for a photoelectric conversion element for imaging according to claim 3, wherein The general formula (1) is represented by any one of the general formulas (10), (11) and (13).

5. The material for a photoelectric conversion element for imaging according to claim 1, wherein The general formulae (5) to (8) are represented by the following general formulae (5A) to (8C): [Chemistry 4] [Chemistry 5] In general formula (5A) to general formula (8C), L 1 ~L 4 ,Ar 12 ~Ar 16 , h to k and * are the same as those described in the general formulae (5) to (8).

6. The material for a photoelectric conversion element for imaging according to claim 1, wherein Ar 1 or Ar 5 At least one of the above-mentioned general formulae (2) to (8) is represented by any one of the general formulae (2) to (8).

7. The material for a photoelectric conversion element for imaging according to claim 5, wherein Ar 1 or Ar 5 At least one of the above-mentioned general formulae (5A) to (8C) is represented by any one of the general formulae (5A) to (8C).

8. The material for a photoelectric conversion element for imaging according to claim 1, wherein L 1 and L 3 For a single key.

9. The material for a photoelectric conversion element for imaging according to claim 1, wherein The energy level of the highest occupied molecular orbital (HOMO) obtained by structure optimization calculation based on density functional calculation B3LYP / 6-31G(d) is -4.5 eV or less.

10. The material for a photoelectric conversion element for imaging according to claim 9, wherein The energy level of the lowest unoccupied molecular orbital (LUMO) obtained by the structure optimization calculation is -2.5 eV or more.

11. The photoelectric conversion element material for imaging according to claim 1, having a 1×10 -6 cm 2 / Vs and above hole mobility. 12 . The imaging photoelectric conversion element material according to claim 1 , which is amorphous. 13 . The material for an imaging photoelectric conversion element according to claim 1 , which is used as a hole transport material of an imaging photoelectric conversion element.

14. A photoelectric conversion element for imaging, comprising a photoelectric conversion layer and an electron blocking layer between two electrodes, wherein the photoelectric conversion element for imaging is characterized in that at least one of the photoelectric conversion layer and the electron blocking layer contains the material for the photoelectric conversion element for imaging as described in claim 1.

15. The imaging photoelectric conversion element according to claim 14, wherein: The electron blocking layer contains the imaging photoelectric conversion element material according to claim 1.

16. The imaging photoelectric conversion element according to claim 14, wherein: The photoelectric conversion layer contains an electron transport material.

17. The imaging photoelectric conversion element according to claim 14, wherein: The electron blocking layer contains the imaging photoelectric conversion element material according to claim 1, and the photoelectric conversion layer contains a fullerene derivative.

Images