Photoelectric conversion element comprising material for photoelectric conversion element

Abstract

Provided is a photoelectric conversion element using a photoelectric conversion element material that can achieve high sensitivity and high resolution. The photoelectric conversion element has one or more organic layers between two electrodes, and in the photoelectric conversion element, at least one organic layer uses a material for photoelectric conversion elements represented by general formula (1). In the formula (1), X1 represents O, S or N-R1, R1 represents an alkyl group having 1-20 carbon atoms, an aromatic hydrocarbon group having 6-30 carbon atoms, or a heteroaromatic group having 3-17 carbon atoms, and Ar1-Ar3 are deuterium, an alkyl group having 1-20 carbon atoms, an aromatic hydrocarbon group having 6-30 carbon atoms, a heteroaromatic group having 3-17 carbon atoms, a group having a tricyclic condensed ring structure of any one of formulae (2a)-(2e), or the like. # imgabs0 #

Description

Technical Field

[0001] The present invention relates to a photoelectric conversion element including a material for a specified photoelectric conversion element, and particularly to a photoelectric conversion element effectively used for a camera device.

[0002] In recent years, the development of organic electronic devices using thin films formed of organic semiconductors has been promoted. For example, an electroluminescent element, a solar cell, a transistor element, a photoelectric conversion element, etc. can be exemplified. In particular, among these, the development of an organic electroluminescence (EL) element as an organic electroluminescent element based on an organic substance is the most advanced. While promoting applications in smartphones or televisions (TVs), etc., development aiming at higher functionality continues.

[0003] In photoelectric conversion elements, heretofore, the development / practical application of elements using P-N junctions of inorganic semiconductors such as silicon has been promoted, and research on higher functionality for digital cameras and smartphone cameras, and research on applications in surveillance cameras, automotive sensors, etc. have been conducted. As problems to be solved for these various uses, high sensitivity and pixel miniaturization (high resolution) are listed. In photoelectric conversion elements using inorganic semiconductors, in order to obtain a color image, a method of disposing color filters corresponding to red, green, and blue (RGB) which are the three primary colors of light on the light-receiving portion of the photoelectric conversion element is mainly adopted. In this method, since the RGB color filters are disposed on a plane, there are problems in terms of the utilization efficiency of incident light or resolution (Non-Patent Document 1, Non-Patent Document 2).

[0004] As one of the solutions to the problems of such photoelectric conversion elements, the development of photoelectric conversion elements using organic semiconductors instead of inorganic semiconductors has been conducted (Non-Patent Document 1, Non-Patent Document 2). This utilizes the property of an organic semiconductor to selectively absorb light in a specific wavelength region with high sensitivity, and it has been proposed to stack photoelectric conversion elements obtained using organic semiconductors corresponding to the three primary colors of light to solve the problems of high sensitivity and high resolution. In addition, an element obtained by stacking a photoelectric conversion element containing an organic semiconductor and a photoelectric conversion element containing an inorganic semiconductor has also been proposed (Non-Patent Document 3).

[0005] Here, a photoelectric conversion element using an organic semiconductor is an element configured as follows. That is, a photoelectric conversion layer containing a thin film of an organic semiconductor is provided between two electrodes, and a hole blocking layer and / or an electron blocking layer is disposed 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 by the photoelectric conversion layer, and then holes and electrons are generated by charge separation of the excitons. Thereafter, the holes and electrons migrate to the respective electrodes, and the light is converted into an electric signal. For the purpose of promoting the above 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 has become one of the problems. In such a 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 the respective layers of the photoelectric conversion element can be roughly classified into P-type organic semiconductors and N-type organic semiconductors. The P-type organic semiconductor is used as a hole transporting material, and the N-type organic semiconductor is used as an electron transporting material. In order to control the migration of holes and electrons in the photoelectric conversion element, various organic semiconductors having appropriate physical properties, such as hole mobility, electron mobility, the energy value of the highest occupied molecular orbital (HOMO), and the energy value of the lowest unoccupied molecular orbital (LUMO), have been developed. However, the situation where sufficient characteristics are not yet achieved and they cannot be effectively utilized commercially.

[0007] In Patent Document 1, the following element is proposed: a derivative in which phenoxazine is substituted at both ends of a dicarbazole is used in an electron blocking layer disposed between a photoelectric conversion layer and an electrode.

[0008] In Patent Document 2 and Patent Document 3, the following element is proposed: a naphthalene derivative having a carbazole skeleton as a tricyclic condensed ring structure is used in an electron blocking layer disposed between a photoelectric conversion layer and an electrode.

[0009] In Patent Document 4, the following element is proposed: a carbazole derivative having a carbazole skeleton as a tricyclic condensed ring structure is used in an electron blocking layer disposed between a photoelectric conversion layer and an electrode.

[0010] In Patent Document 5, the following element is proposed: a spirofluorene derivative having an acridine skeleton as a tricyclic condensed ring structure is used in an electron blocking layer disposed between a photoelectric conversion layer and an electrode.

[0011] Prior Art Documents

[0012] Patent Documents

[0013] Patent Document 1: Japanese Patent Laid-Open No. 2011-228614

[0014] Patent Document 2: Japanese Patent Laid-Open No. 2019-055919

[0015] Patent Document 3: WO2018 / 235780

[0016] Patent Document 4: Japanese Patent Laid-Open No. 2015-153910

[0017] Patent Document 5: Japanese Patent Laid-Open No. 2011-82507

[0018] Non-Patent Document

[0019] Non-Patent Document 1: NHK Technical Research R&D No. 132, pp. 4-11 (March 2012)

[0020] Non-Patent Document 2: NHK Technical Research R&D No. 174, pp. 4-17 (March 2019)

[0021] 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

[0022] Problems to be Solved by the Invention

[0023] For example, for a photoelectric conversion element for imaging, in order to promote the high functionality of digital cameras and cameras for smartphones, or for applications in surveillance cameras, automotive sensors, etc., higher sensitivity and higher resolution have become issues. In view of this situation, an object of the present invention is to provide a material that realizes high sensitivity and high resolution of a photoelectric conversion element, and a photoelectric conversion element using the material.

[0024] Technical Means for Solving the Problems

[0025] The inventors of the present invention made intensive studies, and as a result, found that by using a compound having a specific tricyclic ring-condensed structure, the processes of generating holes and electrons by charge separation of excitons in the photoelectric conversion layer and the processes of migration of holes and electrons in the photoelectric conversion element are efficiently carried out, thus completing the present invention.

[0026] That is, the present invention relates to a photoelectric conversion element having one or more organic layers between two electrodes, and the photoelectric conversion element is characterized in that at least one organic layer contains a material for a photoelectric conversion element represented by the following general formula (1).

[0027] [Chemical Formula 1]

[0028]

[0029] In the general formula (1), X 1 is independently represented by O, S or N-R 1 respectively, and X 1 is preferably independently represented by O or S respectively, and more preferably represented by O.

[0030] R 1 is independently represented by an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms.

[0031] Ar 1 ~Ar 3 are independently deuterium, an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms, or a group having a tricyclic condensed ring structure represented by any one of the following formulas (2a) to (2e), or represent a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms, and a substituted or unsubstituted linked aromatic group formed by linking two to five of any one of the following formulas (2a) to (2e). Among them, when the tricyclic condensed ring structure is included at the end, it is independently represented by the formula (2c) or formula (2d), and when it is not at the end and there are two bonding sites, it is represented by the formula (2a), formula (2b) or formula (2e). It is preferably deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 12 carbon atoms, or a group having a tricyclic condensed ring structure represented by any one of the following formulas (2a) to (2e), or represented by a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms, and a substituted or unsubstituted linked aromatic group formed by linking two to three of any one of the following formulas (2a) to (2e).

[0032] [Chemical Formula 2]

[0033]

[0034] Here, * represents a bonding point.

[0035] Ar 4 independently represents hydrogen, deuterium, an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to five of these aromatic groups.

[0036] X 2 Each independently represents a single bond, O, S or N-R 2 wherein X 2 is preferably represented by a single bond, O or S.

[0037] R 2 Each independently represents an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms.

[0038] s and t independently represent the number of substituents, s and t independently represent an integer of 0 to 2, and s and t are preferably independently represented by 0 to 1.

[0039] In addition, a represents the number of substituents and represents an integer of 1 or 2.

[0040] Wherein, when a = 1, at least one of Ar 1 to Ar 3 contains a group having a tricyclic condensed ring structure of any one of the formulas (2a) to (2e), and preferably at least two contain a group having a tricyclic condensed ring structure of any one of the formulas (2a) to (2e). At this time, when any one of Ar 1 to Ar 3 is a linked aromatic group, two groups having a tricyclic condensed ring structure of any one of the formulas (2a) to (2e) may also be contained in the linked aromatic group.

[0041] In addition, it is also preferably a = 1, and at least one of Ar 1 to Ar 3 contains a group having a tricyclic condensed ring structure represented by the formula (2c), and more preferably at least two of Ar 1 to Ar 3 contain a group having a tricyclic condensed ring structure represented by the formula (2c). In addition, in the above case, when Ar 2 or Ar 3 contains a group having a tricyclic condensed ring structure of any one of the formulas (2a) to (2e), s or t representing the number of substituents is not 0 but 1 or 2.

[0042] Preferably, in the general formula (1), Ar 1 contains any one of the ring structures represented by the following general formulas (3a) to (3m), and more preferably Ar1 Any of the ring structures represented by the following general formulas (3a) to (3m).

[0043] [Chemical formula 3]

[0044]

[0045] When Ar 1 When represented by the general formula (3b), it is preferably bonded at a bonding position such as the following general formula (3b-1) or general formula (3b-2). As examples, the following (P38) or (P39) can be cited.

[0046] [Chemical formula 4]

[0047]

[0048] Here, * represents the bonding point with N in formula (1).

[0049] Ar 1 It is also preferably a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms containing at least one oxygen or sulfur atom.

[0050] The material for a photoelectric conversion element represented by the general formula (1) preferably satisfies any of the following: the energy level of the highest occupied molecular orbital (HOMO) obtained by structural optimization calculation based on density functional calculation B3LYP / 6-31G(d) is -4.0 eV or less, the energy level of the lowest unoccupied molecular orbital (LUMO) obtained by the structural optimization calculation is -2.5 eV or more, has a hole mobility of 1×10 -6 cm 2 / Vs or more, or is amorphous. As the energy level of HOMO, it is preferably -4.5 eV or less and -5.2 eV or more.

[0051] The material for a photoelectric conversion element represented by the general formula (1) can be used as a hole-transporting material in a photoelectric conversion element for imaging.

[0052] In addition, the present invention relates to a photoelectric conversion element for imaging, which has a photoelectric conversion layer and an electron blocking layer between two electrodes. The photoelectric conversion element for imaging is characterized in that it contains the material for a photoelectric conversion element represented by the general formula (1) in at least one of the photoelectric conversion layer and the electron blocking layer.

[0053] Here, in the present invention, the material for a photoelectric conversion element represented by the general formula (1) is preferably included in the electron blocking layer or the photoelectric conversion layer of the photoelectric conversion element, and in this case, it is preferably included as a hole transporting material. The material for a photoelectric conversion element is preferably used for the electron blocking layer. In addition, when the material for a photoelectric conversion element is included in the electron blocking layer, it is preferable to include an electron transporting material in the photoelectric conversion layer, and among them, it is preferable to include a fullerene derivative as the electron transporting material. In addition, at this time, it is preferable to further include, as a hole transporting material, a material having a skeleton as follows, that is, a skeleton containing at least two thiophene rings, in the photoelectric conversion layer.

[0054] In addition, in the present invention, when the material for a photoelectric conversion element represented by the general formula (1) is used for the electron blocking layer of a photoelectric conversion element, the absolute value (|h1 - e1|) of the energy level difference between the energy level (h1) of the HOMO of the hole transporting material used in the photoelectric conversion layer adjacent to the electron blocking layer and the energy level (e1) of the HOMO of the material for a photoelectric conversion element represented by the general formula (1) contained in the electron blocking layer is preferably 1.0 eV or less, and more preferably 0.8 eV or less.

[0055] In addition, when the material for a photoelectric conversion element represented by the general formula (1) is used for the photoelectric conversion layer of a photoelectric conversion element, the absolute value (|h2 - e2|) of the energy level difference between the energy level (h2) of the HOMO of the hole transporting material used in the electron blocking layer adjacent to the photoelectric conversion layer and the energy level (e2) of the HOMO of the material for a photoelectric conversion element represented by the general formula (1) contained in the photoelectric conversion layer is preferably 1.0 eV or less, and more preferably 0.8 eV or less.

[0056] In addition, when the photoelectric conversion layer contains a plurality of materials, the hole transporting material contained in the photoelectric conversion layer means a material having a volume fraction of at least 5% or more and having the largest energy level of HOMO among the materials contained in the photoelectric conversion layer. Similarly, when the electron blocking layer contains a plurality of materials, the hole transporting material contained in the electron blocking layer means a material having a volume fraction of at least 5% or more and having the largest energy level of HOMO among the materials contained in the electron blocking layer.

[0057] Effects of the Invention

[0058] The material for a photoelectric conversion element in the present invention enables appropriate migration of holes or electrons in the photoelectric conversion element. Therefore, in the photoelectric conversion element, it is possible to reduce the leakage current generated due to the application of a bias voltage when converting light into electric energy. As a result, a photoelectric conversion element with a low dark current value and a high contrast ratio can be obtained, and preferably, it is effectively used as a material for a photoelectric conversion element of a photoelectric conversion film stacked type imaging device. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 is a schematic cross-sectional view showing a structural example of a photoelectric conversion element for imaging. Detailed implementation mode

[0060] The photoelectric conversion element for imaging of the present invention has at least one organic layer (i.e., one or more than two organic layers) between two electrodes. Moreover, in the present invention, the material for a photoelectric conversion element represented by the general formula (1) is contained in at least one of its organic layers. Preferably, in a photoelectric conversion element for imaging having a photoelectric conversion layer and an electron blocking layer between two electrodes, the material for a photoelectric conversion element represented by the general formula (1) is contained in at least one of the photoelectric conversion layer and the electron blocking layer.

[0061] Hereinafter, the material for a photoelectric conversion element represented by the general formula (1) may sometimes be referred to as the material for a photoelectric conversion element of the present invention, or sometimes simply as the material for a photoelectric conversion element, the material of the present invention, or the compound represented by the general formula (1).

[0062] Hereinafter, the compound represented by the general formula (1) will be described.

[0063] X 1 Each independently represents O, S or N-R 1 X 1 is preferably each independently represented by O or S, and more preferably represented by O.

[0064] R 1 Each independently represents an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms.

[0065] When R 1 is an unsubstituted alkyl group having 1 to 20 carbon atoms, as the alkyl group, it can be any one of a straight-chain, branched-chain, or cyclic alkyl group, and preferably a straight-chain, branched-chain, or cyclic alkyl group having 1 to 10 carbon atoms. As specific examples thereof, 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, tert-butyl, neopentyl, 2-ethylhexyl, and 2-hexyloctyl, and saturated alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cyclooctyl, 4-butylcyclohexyl, and 4-dodecylcyclohexyl can be exemplified. In addition, the alkyl group having 1 to 20 carbon atoms can be any one of a straight-chain, branched-chain, or cyclic alkyl group.

[0066] Regarding R 1 ​is an unsubstituted aromatic hydrocarbon compound having 6 to 30 carbon atoms. Preferred carbon numbers are 6 to 18. Examples of the aromatic hydrocarbon compound having 6 to 30 carbon atoms include groups derived from monocyclic aromatic hydrocarbons such as benzene, bicyclic aromatic hydrocarbons such as naphthalene, tricyclic aromatic hydrocarbons such as benzoindene, biphenylene, fluorene, anthracene, phenanthrene, and fluorene, tetracyclic aromatic hydrocarbons such as fluoranthene, acephenanthrylene, aceanthrylene, triphenylene, pyrene, tetraphene, benzopentaphene, pleiadene, etc. Preferred are benzene, naphthalene, anthracene, phenanthrene, triphenylene, or pyrene, and more preferred are groups derived from benzene, naphthalene, anthracene, phenanthrene, pyrene, and triphenylene.

[0067] Regarding R 1 is an unsubstituted heteroaromatic group having 3 to 17 carbon atoms. Preferred carbon numbers are 3 to 12, and more preferred carbon numbers are 6 to 12. Examples of the heteroaromatic group having 3 to 17 carbon atoms include groups derived from nitrogen-containing aromatic compounds having a pyrrole ring such as pyrrole, pyrrolopyrrole, indole, isoindole, pyrroloisoindole, and carboline, and sulfur- or oxygen-containing aromatic compounds such as thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, carbazole, indolocarbazole, pyridine, pyrimidine, quinoline, isoquinoline, quinazoline, or quinoxaline. Preferred are groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, or carbazole, and more preferred are dibenzothiophene group, dibenzofuran group, or carbazole group.

[0068] Ar 1 ~Ar 3Each independently is deuterium, an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms, or a group having a tricyclic fused-ring structure represented by any one of the formulas (2a) to (2e), or represents a substituted or unsubstituted linked aromatic group formed by linking two to five of a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms, and any one of the formulas (2a) to (2e). Among them, when the tricyclic fused-ring structure is included at the terminal, it is independently represented by the formula (2c) or formula (2d), and when it is not at the terminal and there are two bonding sites, it is represented by the formula (2a), formula (2b) or formula (2e). Preferably, it is deuterium, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 12 carbon atoms, or a group having a tricyclic fused-ring structure represented by any one of the following formulas (2a) to (2e), or is represented by a substituted or unsubstituted linked aromatic group formed by linking two to three of an aromatic hydrocarbon group having 6 to 18 carbon atoms, a heteroaromatic group having 3 to 17 carbon atoms, and any one of the following formulas (2a) to (2e).

[0069] When Ar 1 ~Ar 3 is an alkyl group having 1 to 20 carbon atoms, the preferred number of carbon atoms is 1 to 10. Examples of the alkyl group having 1 to 20 carbon atoms are the same as those described for R 1 above.

[0070] When Ar 1 ~Ar 3 is an unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, the preferred number of carbon atoms is 6 to 18. Examples of the aromatic hydrocarbon group having 6 to 30 carbon atoms are the same as those described for R 1 above.

[0071] When Ar 1 ~Ar 3 is an unsubstituted heteroaromatic group having 3 to 17 carbon atoms, the preferred number of carbon atoms is 6 to 12. Examples of the heteroaromatic group having 3 to 17 carbon atoms include, in addition to those described for R 1 above, groups having a tricyclic fused-ring structure represented by the formulas (2a) to (2e).

[0072] When Ar 1 ~Ar 3In the case of an unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, an unsubstituted heteroaromatic group having 3 to 17 carbon atoms, and an unsubstituted linked aromatic group formed by linking two to five of the formulas (2a) to (2e), the preferred number of links is 2 to 3, and the more preferred number of links is 2. Further, in Ar 1 ~Ar 3 is a linked aromatic group, Ar 1 ~Ar 3 , and the group described in the formula (1) can be bonded using an aromatic hydrocarbon group, a heteroaromatic group, or any one of the formulas (2a) to (2e) contained in the linked aromatic group, and can be bonded at both ends or branched.

[0073] Ar 4 independently represents deuterium, an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to five of these aromatic groups. When Ar 4 is an alkyl group having 1 to 20 carbon atoms, the preferred number of carbon atoms is 1 to 10. Examples of the alkyl group having 1 to 20 carbon atoms are the same as those described for R 1 . When Ar 4 is an unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, the preferred number of carbon atoms is 6 to 18. Examples of the aromatic hydrocarbon group having 6 to 30 carbon atoms are the same as those described for R 1 .

[0074] X 2 are each independently represented by a single bond, O, S, or N-R 2 , and X 2 is preferably represented by a single bond, O, or S.

[0075] R 2 are each independently represented by an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms. When R 2 is an unsubstituted alkyl group having 1 to 20 carbon atoms, the preferred number of carbon atoms is 1 to 10. Examples of the alkyl group having 1 to 20 carbon atoms are the same as those described for R 1 . When Ar 4 is an unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, the preferred number of carbon atoms is 6 to 18. Examples of the aromatic hydrocarbon group having 6 to 30 carbon atoms are the same as those described for R 1 . When Ar 4When it is an unsubstituted heteroaromatic group having 3 to 17 carbon atoms, the preferred number of carbon atoms is 3 to 12. Examples of the heteroaromatic group having 3 to 17 carbon atoms are the same as those described for R 1 above.

[0076] s and t independently represent the number of substitutions, s and t independently represent an integer of 0 to 2, and s and t are preferably independently represented by 0 to 1.

[0077] a represents the number of substitutions and represents an integer of 1 or 2. Among them, when a = 1, at least one of Ar 1 ~Ar 3 contains a group having a tricyclic condensed ring structure represented by any one of the formulas (2a) to (2e), and preferably at least two contain a group having a tricyclic condensed ring structure represented by any one of the formulas (2a) to (2e). When any one of Ar 1 ~Ar 3 is a linking aromatic group, two groups having a tricyclic condensed ring structure represented by any one of the formulas (2a) to (2e) may also be contained in the linking aromatic group.

[0078] In addition, it is also preferred that a = 1 and at least one of Ar 1 ~Ar 3 contains a group having a tricyclic condensed ring structure represented by the formula (2c), and more preferably at least two of Ar 1 ~Ar 3 contain a group having a tricyclic condensed ring structure represented by the formula (2c).

[0079] Preferably, Ar 1 contains any one of the ring structures represented by the general formulas (3a) to (3m), and more preferably Ar 1 is any one of the ring structures represented by the general formulas (3a) to (3m).

[0080] Among the ring structures represented by the general formulas (3a) to (3m), (3b), (3e), (3f), (3g), (3h), (3i) and (3m) are preferred, and (3b), (3e), (3f), (3h) and (3m) are more preferred.

[0081] Ar 1 is also preferably a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms containing at least one oxygen or sulfur atom. Examples include heteroaromatic groups containing a furan ring or a thiophene ring and having a ring formed by condensing these with an aromatic hydrocarbon ring. The aromatic hydrocarbon ring to be condensed may be single or multiple, but is not limited to these.

[0082] In the present specification, an unsubstituted linked aromatic group means an aromatic group in which two or more aromatic groups selected from the aromatic hydrocarbon group, the heteroaromatic group, and the group having a tricyclic condensed ring structure represented by the formula (2a) to the formula (2e) are bonded by a single bond. These linked aromatic groups may be linear or branched. When benzene rings are linked to each other, the linking position may be any of ortho, meta, and para, and para-linking or meta-linking is preferred. The aromatic group may be an aromatic hydrocarbon group, a heteroaromatic group, or a group having a tricyclic condensed ring structure represented by the formula (2a) to the formula (2e), and a plurality of aromatic groups may be the same or different.

[0083] In the present specification, examples of the substitutable substituent such as an aromatic hydrocarbon group which may be substituted or unsubstituted, such as an aromatic hydrocarbon group having 6 to 30 carbon atoms, include deuterium, a cyano group, or an alkyl group having 1 to 20 carbon atoms.

[0084] Among them, when the substituent is an alkyl group having 1 to 20 carbon atoms, the alkyl group may be any of linear, branched, and cyclic alkyl groups, and 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, tert-butyl, neopentyl, 2-ethylhexyl, and 2-hexyloctyl; and saturated alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cyclooctyl, 4-butylcyclohexyl, and 4-dodecylcyclohexyl.

[0085] In addition, in the present invention, the substituent is bonded to a carbon atom or a heteroatom constituting the aromatic ring.

[0086] Preferred specific examples of the material for a photoelectric conversion element represented by the general formula (1) of the present invention are shown below, but are not limited thereto. In addition, the numbers in parentheses represent the compound numbers.

[0087] [Chemical formula 5]

[0088]

[0089] [Chemical formula 6]

[0090]

[0091] [Chemical formula 7]

[0092]

[0093] [Chemical formula 8]

[0094]

[0095] [Chemical formula 9]

[0096]

[0097] [Chemical Formula 10]

[0098]

[0099] [Chemical Formula 11]

[0100]

[0101] The material for a photoelectric conversion element of the present invention can be obtained by the following method: after synthesis by a method based on various organic synthesis reactions established in the field of organic synthetic chemistry, including Suzuki coupling, Stille coupling, Grignard coupling, Ullmann coupling, Buchwald-Hartwig reaction, Heck reaction, etc., using commercially available reagents as raw materials, and then purified by known methods such as recrystallization, column chromatography, sublimation purification, etc., but not limited to the above methods.

[0102] Regarding the material for a photoelectric conversion element of the present invention, 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 -4.0 eV or lower, more preferably in the range of -5.0 eV to -4.5 eV.

[0103] In addition, the energy level of the lowest unoccupied molecular orbital (LUMO) obtained by the above structure optimization calculation is preferably -2.5 eV or higher, more preferably in the range of -2.5 eV to -0.9 eV.

[0104] Regarding the material for a photoelectric conversion element of the present invention, the difference (absolute value) between the HOMO energy level and the LUMO energy level is preferably in the range of 2.0 eV to 5.0 eV, more preferably in the range of 2.5 eV to 4.0 eV.

[0105] The material for a photoelectric conversion element of the present invention preferably has a hole mobility of 1×10 -6 cm 2 / Vs to 1 cm 2 / Vs, more preferably has a hole mobility of 2×10 -5 cm 2 / Vs to 1×10 -1 cm 2The hole mobility of / Vs. The hole mobility can be evaluated by known methods such as a method based on a field effect transistor (FET) type transistor element, a method based on the time-of-flight method, and a space charge limited current (SCLC) method.

[0106] The material for the photoelectric conversion element of the present invention is preferably amorphous. In the case of being amorphous, it can be confirmed by various methods. For example, it can be confirmed by the case where no peak is detected by using the X-Ray diffraction (XRD) method or the case where no endothermic peak is detected by using the differential scanning calorimetry (DSC) method.

[0107] Next, a photoelectric conversion element for imaging using the material for the photoelectric conversion element of the present invention will be described, but the structure of the photoelectric conversion element for imaging of the present invention is not limited thereto. The description will be made with reference to the drawings.

[0108] Figure 1 is a cross-sectional view schematically showing the structure of a photoelectric conversion element for imaging using the material for the photoelectric conversion element for imaging of the present invention. 1 represents a substrate, 2 represents an electrode, 3 represents an electron blocking layer, 4 represents a photoelectric conversion layer, 5 represents a hole blocking layer, and 6 represents an electrode. It is not limited to Figure 1 such a structure, and layers can be added or omitted as needed. It can also be a structure opposite to Figure 1 that is, layers are stacked on the substrate 1 in the order of electrode 6, hole blocking layer 5, photoelectric conversion layer 4, electron blocking layer 3, and electrode 2. In this case, layers can also be added or omitted as needed. In addition, in the photoelectric conversion element for imaging as described above, sometimes in addition to electrodes such as an anode or a cathode, the layers constituting the stacked structure on the substrate are collectively referred to as organic layers.

[0109] Hereinafter, each component and each layer of the photoelectric conversion element of the present invention will be described.

[0110] - Substrate -

[0111] The photoelectric conversion element is preferably supported on a substrate. Regarding the substrate, there is no particular limitation. For example, a substrate containing glass, transparent plastic, quartz, etc. can be used.

[0112] - Electrode -

[0113] The electrode has the function of collecting 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. For example, 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, fluorine doped tin oxide (FTO) and other conductive transparent materials, metals such as gold, silver, platinum, chromium, aluminum, iron, cobalt, nickel and tungsten, inorganic conductive substances such as copper iodide and copper sulfide, and conductive polymers such as polythiophene, polypyrrole and polyaniline can be exemplified. Regarding these materials, a variety of them can be used in combination as needed. In addition, two or more layers can be stacked.

[0114] - Photoelectric conversion layer -

[0115] The photoelectric conversion layer is a layer that generates holes and electrons through the charge separation of excitons generated by using incident light. It can be formed by a single photoelectric conversion material, or can be formed in combination with a P-type organic semiconductor material as a hole transporting material or an N-type organic semiconductor material as an electron transporting 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 having the function of absorbing light of a desired wavelength in the visible region. Regarding the P-type organic semiconductor material as a hole transporting material, the material for the photoelectric conversion element of the present invention can be used.

[0116] As the P-type organic semiconductor material, as long as it is a material having hole transporting properties, it is preferably the material for the photoelectric conversion element of the present invention, but other P-type organic semiconductor materials can also be used. In addition, two or more of the compounds represented by the general formula (1) (the material for the photoelectric conversion element of the present invention) can be used in combination. Furthermore, the compound and other P-type organic semiconductor materials can also be used in combination.

[0117] As other P-type organic semiconductor materials, as long as they are materials having hole transporting properties, for example, naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, pyrene derivatives, Derivatives, condensed tetraphene derivatives, triphenylene derivatives, perylene derivatives, fluoranthene derivatives, fluorene derivatives, cyclopentadiene derivatives, furan derivatives, thiophene derivatives, pyrrole derivatives, benzofuran derivatives, benzothiophene derivatives, dinaphthothiophenothiophene derivatives, indole derivatives, pyrazoline derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, carbazole derivatives, indolocarbazole and other aromatic compounds, aromatic amine derivatives, styrylamine derivatives, benzidine derivatives, porphyrin derivatives, phthalocyanine derivatives, or quinacridone derivatives.

[0118] In addition, as the P-type organic semiconductor material, a polymer type can be used. Examples of the polymer type P-type organic semiconductor material include: poly(phenylacetylene) derivatives, poly(p-phenylene) derivatives, poly(fluorene) derivatives, poly(vinylcarbazole) derivatives, poly(thiophene) derivatives. In addition, two or more selected from the compounds represented by the general formula (1) of the present invention, the P-type organic semiconductor material, or the polymer type P-type organic semiconductor material can be used in combination.

[0119] As the N-type organic semiconductor material, any material having electron transporting properties can be used. Examples include naphthalene tetracarboxylic diimide or perylene tetracarboxylic diimide, fullerenes (fullerene derivatives), imidazole, thiazole, thiadiazole, oxazole, oxadiazole, triazole and other azole derivatives. In addition, two or more materials selected from the N-type organic semiconductor materials can be used in combination.

[0120] - Electron blocking layer -

[0121] 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 the function of transporting the holes 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. As the hole transporting material in the electron blocking layer, a P-type organic semiconductor material can be used. As the P-type organic semiconductor material, any material having hole transporting properties can be used. Preferably, the compound represented by the general formula (1) is used, and other P-type organic semiconductor materials can also be used. In addition, the compound represented by the general formula (1) can be used in combination with the above-mentioned other P-type organic semiconductor materials or polymer type P-type organic semiconductor materials.

[0122] - Hole blocking layer -

[0123] 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 for transferring 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 having electron transport properties can be used in the hole blocking layer. As the N-type organic semiconductor material, any material having electron transport properties may be used, for example: polycyclic aromatic polycarboxylic acid anhydride or imide thereof such as naphthalenetetracarboxylic acid diimide or perylenetetracarboxylic acid diimide, fullerenes (fullerene derivatives) such as C60 or C70, azole derivatives such as imidazole, thiazole, thiadiazole, oxazole, oxadiazole, triazole, tris(8-hydroxyquinolinol)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 materials selected from the N-type organic semiconductor materials may be used in combination.

[0124] 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), (2a), (2b), (2c), (2d), (2e), (3a), (3b), (3c), (3d), (3e), (3f), (3g), (3h), (3i), (3j), (3k), and (3m), Ar 1 ,Ar 2 ,Ar 3 ,Ar 4 , R 1 , and R 2 As a substituent, part or all of the hydrogen atoms on the alkyl group or the aromatic ring may be deuterated.

[0125] 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.

[0126] 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.

[0127] The organic layer containing the photoelectric conversion element material of the present invention may be formed into a plurality of layers as necessary.

[0128] Example

[0129] Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to these examples.

[0130] Calculation Example

[0131] Calculation of HOMO and LUMO Values

[0132] For the compounds P1, P4, P20, P38, P39, P41, P50, P51, P52, P55, P63, P64, and P65, the HOMO and LUMO were calculated. In addition, for the calculation, a calculation based on the density functional method (density functional theory (DFT: Density Functional Theory)) was used, Gaussian was used as the calculation program, and the calculation was carried out through a structural optimization calculation based on density functional calculation B3LYP / 6-31G(d). The results are shown in Table 1. It can be said that any material of the present invention has preferable HOMO and LUMO values.

[0133] For comparison, for the compounds H1, H2, H3, H4, and H5, the HOMO and LUMO were calculated using the same method as described above. The results are shown in Table 1.

[0134] [Chemical Formula 12]

[0135]

[0136] [Table 1]

[0137]

[0138] Hereinafter, as representative examples, the synthesis examples of compounds P1, P39, and P51 are shown. For other compounds, synthesis was also carried out using a similar method.

[0139] Synthesis Example 1 (Synthesis of Compound P1)

[0140] [Chemical Formula 13]

[0141]

[0142] Into a 300 ml three-necked flask that had been degassed and replaced with nitrogen, T1 (16.0 mmol), T2 (6.9 mmol), bis(tri-tert-butylphosphine)palladium(0) (0.6 mmol), and sodium tert-butoxide (21.1 mmol) were charged. After adding 40 ml of xylene thereto, the mixture was stirred at 150 °C for 6 hours. After temporarily cooling to room temperature, the reaction solution was concentrated to dryness and purified by column chromatography. Thereafter, reprecipitation was performed using xylene and isopropanol to obtain Compound 1 (white solid). The yield was 67%. The obtained solid was evaluated by the XRD method, but no peaks were detected. Thus, it was confirmed that Compound P1 was amorphous. APCI-TOFMS m / z 590 [M+1] +

[0143] Synthesis Example 2 (Synthesis of Compound P39)

[0144] [Chemical Formula 14]

[0145]

[0146] Compound P39 (white solid) was obtained in the same manner as in Synthesis Example 1, except that T1 was changed to T3 and T2 was changed to T4. The yield was 21%. The obtained solid was evaluated by the XRD method, but no peaks were detected. APCI-TOFMS m / z 679 [M+1] +

[0147] Synthesis Example 3 (Synthesis of Compound P51)

[0148] [Chemical Formula 15]

[0149]

[0150] Compound P51 (white solid) was obtained in the same manner as in Synthesis Example 1, except that T3 was changed to T5. The yield was 43%. The obtained solid was evaluated by the XRD method, but no peaks were detected. APCI-TOFMS m / z 591 [M+1] +

[0151] Measurement of Charge Mobility

[0152] On an electrode including ITO with a film thickness of 110 nm formed on a glass substrate, Compound 1 was formed into a film under the condition of a film thickness of about 3 μm by vacuum evaporation to serve as an organic layer. Subsequently, an element in which aluminum (Al) was formed to a thickness of 70 nm was used as an electrode, and charge mobility was measured by the time-of-flight method. The hole mobility was 1.3×10 -4 cm 2 / Vs.

[0153] Except for replacing Compound 1 with the compounds shown in Table 2, the hole mobilities of the respective compounds were measured in the same manner as described above.

[0154] The results are shown in Table 2.

[0155] [Table 2]

[0156] Example 1

[0157] On an electrode including ITO with a film thickness of 70 nm formed on a glass substrate, Compound P1 was formed into a film with a thickness of 10 nm at a vacuum degree of 4.0×10 -5 Pa as an electron blocking layer. Subsequently, as a photoelectric conversion layer, 2Ph-BTBT (hole transporting material), F6-SubPc-OC6F5 (dye material), and fullerene (C60, electron transporting material) were co-evaporated with an evaporation rate ratio of 4:4:2 to form a film with a thickness of 200 nm. Then, dpy-NDI was evaporated to a thickness of 10 nm to form a hole blocking layer. Finally, aluminum was formed into a film with a thickness of 70 nm as an electrode to fabricate a photoelectric conversion element. When a voltage of 2.6 V was applied with ITO and aluminum as electrodes, the current in the dark (dark current) was 3.7×10 -10 A / cm 2 . In addition, when a voltage of 2.6 V was applied and light irradiation was performed from a height of 10 cm to the ITO electrode side with an LED adjusted to a light irradiation wavelength of 500 nm and 1.6 μW, the current (bright current) was 3.0×10 -7 A / cm 2 . The light-to-dark ratio when a voltage of 2.6 V was applied was 8.1×10 2 . These results are shown in Table 3.

[0158] Examples 2 to 13

[0159] Except for using the compounds shown in Table 3 as the electron blocking layer, a photoelectric conversion element was fabricated in the same manner as in Example 1.

[0160] Comparative Examples 1 to 5

[0161] Except for using the compounds shown in Table 3 as the electron blocking layer, a photoelectric conversion element was fabricated in the same manner as in Example 1.

[0162] The results of Examples 1 to 13 and Comparative Examples 1 to 5 are shown in Table 3.

[0163] In addition to the compounds shown in Table 1, the calculated results of the HOMO and LUMO of the compounds used in the examples and comparative examples are shown in Table 4. In addition, for the calculation, as in the previous case, a calculation based on the density functional method (DFT: Density Functional Theory) was used, Gaussian was used as the calculation program, and the calculation was performed through a structure optimization calculation based on the density functional calculation B3LYP / 6-31G(d).

[0164] [Chemical Formula 16]

[0165]

[0166] [Table 3]

[0167]

[0168] [Table 4]

[0169]

[0170] From the results of Table 3, it can be seen that the photoelectric conversion element using the compound of the present invention exhibits a low dark current value and a high light-to-dark ratio.

[0171] Industrial Applicability

[0172] The material for a photoelectric conversion element for imaging of the present invention enables appropriate migration of holes or electrons in the photoelectric conversion element. Therefore, it is possible to reduce the leakage current generated when light is converted into electric energy due to the application of a bias voltage. As a result, a photoelectric conversion element with a low dark current value and a high light-to-dark ratio can be obtained. The material of the present invention is effectively used as a material for a photoelectric conversion element of a photoelectric conversion film stack type imaging device.

[0173] Explanation of Reference Numerals

[0174] 1: Substrate

[0175] 2: Electrode

[0176] 3: Electron blocking layer

[0177] 4: Photoelectric conversion layer

[0178] 5: Hole blocking layer

[0179] 6: Electrode

Claims

1. A photoelectric conversion element having one or more organic layers between two electrodes, wherein at least one organic layer in the photoelectric conversion element contains a material for a photoelectric conversion element represented by the following general formula (1). [Chemical formula 1] wherein, X 1 each independently represents O, S or N-R 1 . R 1 Each independently represents an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms. Ar 1 ~Ar 3 Each independently represents deuterium, an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms, or a group having a tricyclic condensed ring structure represented by any one of the following formulas (2a) to (2e), or represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms, and a substituted or unsubstituted linked aromatic group formed by linking two to five of any one of the following formulas (2a) to (2e); wherein, In the case of containing the tricyclic condensed ring structure at the terminal, it is independently represented by the following formula (2c) or formula (2d), and in the case of not being at the terminal and having two bonding sites, it is represented by the formula (2a), formula (2b) or formula (2e). [Chemical formula 2] * represents a bonding point. Ar 4 independently represents hydrogen, deuterium, an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted linked aromatic group formed by linking two to five of these aromatic groups. X 2 each independently represents a single bond, O, S or N-R 2 。R 2 each independently represents an alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms. s and t independently represent the number of substitutions, and s and t independently represent an integer of 0 to 2. a represents the number of substitutions and represents an integer of 1 or 2. Among them, when a = 1, Ar 1 ~Ar 3 at least one of them contains a group having a tricyclic ring-condensed structure of any one of the formulas (2a) to (2e).

2. The optoelectronic conversion element according to claim 1, wherein, In the general formula (1), Ar 1 contains any one of the ring structures represented by the following general formulas (3a) to (3m). [Chemical formula 3] 3. The photoelectric conversion element according to claim 1, wherein In the general formula (1), X 2 is represented by a single bond, O or S.

4. The photoelectric conversion element according to claim 1, wherein, In the general formula (1), Ar 1 contains at least one substituted or unsubstituted heteroaromatic group having 3 to 17 carbon atoms containing an oxygen or sulfur atom.

5. The optoelectronic conversion element according to claim 1, wherein, In the general formula (1), Ar 1 is any one of the ring structures represented by the general formula (3a) to the general formula (3m).

6. The optoelectronic conversion element according to claim 1, wherein, In the general formula (1), a = 1, and at least two of Ar 1 ~Ar 3 contain a group having a tricyclic fused-ring structure of any one of the formulas (2a) to (2e).

7. The photoelectric conversion element according to claim 1, wherein, In the general formula (1), a = 1, and at least one of Ar 1 ~Ar 3 contains a group having a tricyclic condensed ring structure represented by the formula (2c).

8. The photoelectric conversion element according to claim 7, wherein, In the general formula (1), Ar 1 ~Ar 3 at least two of which contain a group having a tricyclic condensed ring structure represented by the formula (2c).

9. The optoelectronic conversion element according to claim 1, wherein In the material for a photoelectric conversion element represented by the general formula (1), the energy level of the highest occupied molecular orbital (HOMO) obtained by structural optimization calculation based on density functional calculation B3LYP / 6-31G(d) is -4.0 eV or less.

10. The optoelectronic conversion element according to claim 1, characterized in that, In the material for a photoelectric conversion element represented by the general formula (1), the energy level of the lowest unoccupied molecular orbital (LUMO) obtained by structural optimization calculation based on density functional calculation B3LYP / 6-31G(d) is -2.5 eV or more.

11. The optoelectronic conversion element according to claim 1, wherein, The material for a photoelectric conversion element represented by the general formula (1) has a hole mobility of 1×10 -6 cm 2 / Vs or more.

12. The optoelectronic conversion element according to claim 1, wherein, The material for a photoelectric conversion element represented by the general formula (1) is amorphous.

13. The optoelectronic conversion element according to claim 1, wherein The material for a photoelectric conversion element represented by the general formula (1) is used as a hole transporting material.

14. The photoelectric conversion element according to claim 1, which is a photoelectric conversion element for imaging having a photoelectric conversion layer and an electron blocking layer as organic layers between two electrodes, and is characterized in that, The electron blocking layer contains the material for a photoelectric conversion element represented by the general formula (1).

15. The optoelectronic conversion element according to claim 14, characterized in that, The absolute value of the energy level difference between the highest occupied molecular orbital of the material for a photoelectric conversion element represented by the general formula (1) and the hole transporting material contained in the photoelectric conversion layer is 1.0 eV or less.

16. The optoelectronic conversion element according to claim 14, wherein An electron transporting material is contained in the photoelectric conversion layer.

17. The optoelectronic conversion element according to claim 16, characterized in that, A fullerene derivative is contained in the photoelectric conversion layer as an electron transporting material.

18. The optoelectronic conversion element according to claim 16, characterized in that, A material having a skeleton containing at least two thiophene rings is contained in the photoelectric conversion layer as a hole transporting material.

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