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

Abstract

Provided are: a material for photoelectric conversion elements, which achieves high sensitivity and high resolution in an imaging photoelectric conversion element; and an imaging photoelectric conversion element. A material for photoelectric conversion elements, which is represented by general formula (1) or general formula (2); in addition, the photoelectric conversion element for imaging has a photoelectric conversion layer and an electron blocking layer between two electrodes, and at least one of the layers contains the material. Ring E independently represents a heterocyclic ring represented by formula (1a) that is condensed at an arbitrary position with an adjacent ring. Ar1, Ar2, Ar5 and Ar6 are each independently a diarylamino group having 12-30 carbon atoms, an aryl heteroarylamino group having 12-30 carbon atoms, a diarheteroarylamino group having 12-30 carbon atoms, an aromatic hydrocarbon group having 6-30 carbon atoms, or a heteroaromatic group having 4-18 carbon atoms, and at least one of Ar1, Ar2, Ar5 and Ar6 is the amino group or the amino group formed by further ring shrinkage. # 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 by 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 as electric field light-emitting elements based on organic matter is the most advanced, and while promoting applications in smart phones or televisions (TV), etc., development with the goal of higher functionality continues.

[0003] In the photoelectric conversion element, previously, the development / practical application of the element using the PN junction of inorganic semiconductors such as silicon has been promoted, and the research on the high-functionality of digital cameras and smartphone cameras, and the research on the application in surveillance cameras, automotive sensors, etc. are being carried out. As the subject 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, blue (RGB), which is the three primary colors of light, on the light receiving part of the photoelectric conversion element is mainly adopted. In the described 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 utilizing the photoelectric conversion layer to absorb light having a desired wavelength, and then holes and electrons are generated by charge separation of the excitons. Thereafter, the light is converted into an electrical signal by the 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 as described above, 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] Here, Patent Document 1 proposes a device using an indolocarbazole derivative in an electron blocking layer disposed between a photoelectric conversion layer and an electrode.

[0008] On the other hand, Patent Document 2 proposes an organic EL device using an indolocarbazole compound substituted with a nitrogen-containing six-membered ring structure.

[0009] Patent Document 3 discloses an organic EL device using an indolocarbazole compound substituted with a carbazole structure, but does not specifically show excellent properties as a material for a photoelectric conversion device.

[0010] Prior art literature

[0011] Patent Literature

[0012] Patent Document 1 Japanese Patent Application Publication No. 2018-85427

[0013] Patent Document 2WO2008 / 056746

[0014] Patent document 3WO2009 / 136595

[0015] Non-patent literature

[0016] Non-patent literature 1 NHK R&D No.132, pp.4-11 (2012.3)

[0017] Non-patent literature 2 NHK R&D No. 174, pp. 4-17 (2019.3)

[0018] 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

[0019] Problems to be solved by the invention

[0020] 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.

[0021] Technical means of solving problems

[0022] 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 substituent including an amine skeleton, thereby completing the present invention. In particular, it has been newly found that by using the compound of the present invention, the process of charge generation and 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.

[0023] The present invention is a material for a photoelectric conversion element for imaging, which is represented by the following general formula (1) or general formula (2).

[0024] [Chemistry 1]

[0025]

[0026] In the general formulae (1) and (2), ring E independently represents a heterocyclic ring represented by the formula (1a) which is condensed with an adjacent ring at any position.

[0027] Here, X is O, S, C(Ra)2 or N-(Ar 5 ) p -(Ar 6 ) q Represented by O, S or N-(Ar 5 ) p -(Ar 6 ) q express.

[0028] In the general formula (1), Ar 1 ,Ar 2 ,Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 4 to 18 carbon atoms. 1 ,Ar 2 ,Ar 5 and Ar 6 In the case of a substituted or unsubstituted heteroaromatic group, the number of carbon atoms is preferably 6 to 18. 1 ,Ar 2 ,Ar 5 and Ar 6 The amine groups in the above-mentioned may be condensed as shown in the formula (3a) to the formula (3d) described later.

[0029] When the number of repetitions n in the general formula (1) is plural, n Ar 1 They may be the same or different from each other. 5 In addition, when the number of substitutions m is plural, m Ar 2 When there are multiple substitution numbers q, Ar 6 The same is true.

[0030] For Ar in the general formula (2) 1 ,Ar 5 and Ar 6, as in the case of general formula (1), each independently represents a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 4 to 18 carbon atoms. 1 ,Ar 5 and Ar 6 In the case of a substituted or unsubstituted heteroaromatic group, the number of carbon atoms is preferably 6 to 18. 1 ,Ar 2 ,Ar 5 and Ar 6 The amine groups in the above-mentioned may be condensed as shown in the formula (3a) to the formula (3d) described later.

[0031] Furthermore, when the number of repetitions n in the general formula (2) is plural, n Ar 1 They may be the same or different from each other. 5 In addition, when the number of substitutions p is plural, p Ar 6 They may be the same as or different from each other.

[0032] n, p and s represent the number of repetitions, n and p independently represent integers of 0 to 4, and s represents an integer of 1 to 4. n and p are preferably 0 to 2, and s is preferably 1 to 3. In addition, m and q represent the number of substitutions, and m and q independently represent integers of 1 to 3. m and q are preferably 1 to 2. When n is 0, m is 1, and when p is 0, q is 1.

[0033] Ra 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 4 to 18 carbon atoms.

[0034] In the general formula (1) and the general formula (2), at least one Ar 1 ,Ar 2 ,Ar 5 or Ar 6 The amine groups are represented by any one of the following formulae (3a) to (3d), which are substituted or unsubstituted diarylamine groups having 12 to 30 carbon atoms, substituted or unsubstituted arylheteroarylamine groups having 12 to 30 carbon atoms, or substituted or unsubstituted diheteroarylamine groups having 12 to 30 carbon atoms, or further condensed amine groups. 1 or Ar 5 When the amino group in the formula is further condensed to form a group, it is represented by formula (3a) or formula (3b), in which Ar 2or Ar 6 When the amino group in is further condensed into a group, it is represented by the following formula (3c) or (3d).

[0035] [Chemistry 2]

[0036]

[0037] Y is each independently represented by a single bond, Si(Rb)2, C(Rb)2, O, S, Se or N-Rb, preferably represented by Si(Rb)2, C(Rb)2, O or S.

[0038] Rb 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 4 to 18 carbon atoms.

[0039] Ar 3 and Ar 4 Each independently represents a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 4 to 18 carbon atoms. 3 and Ar 4 In the case of a substituted or unsubstituted heteroaromatic group, the number of carbon atoms is preferably 6 to 18.

[0040] In the general formula (1) and the general formula (2), Ar is preferably 1 ,Ar 2 ,Ar 5 and Ar 6 At least one of them is represented by a substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamine group having 12 to 30 carbon atoms, or a substituted or unsubstituted diheteroarylamine group having 12 to 30 carbon atoms.

[0041] Among them, Ar is preferred 1 ,Ar 2 ,Ar 5 and Ar 6 At least one or two of them are substituted or unsubstituted diarylamine groups having 12 to 30 carbon atoms, or are represented by substituted or unsubstituted arylheteroarylamine groups having 12 to 27 carbon atoms.

[0042] Here, in the general formula (1), it is preferred that at least one of the following conditions (i), (ii), (iii), (iv), (v), (vi), (vii) or (viii) is satisfied, and it is more preferred that at least two of the conditions are satisfied.

[0043] Right now,

[0044] (i) When n=2 to 4, adjacent Ar 1 At least one group of them is phenyl, and they form a biphenyl group.

[0045] (ii) Adjacent Ar 1 with Ar 2 They are phenyl respectively and form biphenyl.

[0046] (iii) When p=2 to 4, adjacent Ar 5 At least one group of them is phenyl, and they form a biphenyl group.

[0047] (iv) Adjacent Ar 5 with Ar 6 They are phenyl respectively and form biphenyl.

[0048] (v) at least one Ar 1 It is a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group.

[0049] (vi) at least one Ar 2 It is a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group.

[0050] (vii) at least one Ar 5 It is a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group.

[0051] (viii) at least one Ar 6 It is a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms, and the aryl group of the amine group has at least one biphenyl group.

[0052] Ar 1 ,Ar 2 ,Ar 5 and Ar 6At least one or two of them are preferably represented by any one of the formulas (3a) to (3d). 1 or Ar 5 is selected from the formula (3a) or formula (3b), Ar 2 or Ar 6 Selected from formula (3c) or formula (3d).

[0053] Ar 1 ,Ar 2 ,Ar 5 or Ar 6 Furthermore, at least one of them is preferably represented by a carbazolyl group, a dibenzofuranyl group, or a dibenzothiophenyl group.

[0054] a and b represent the number of substitutions, and are independently 0 to 3. a and b are preferably 0 to 2. In formulae (3a) to (3d), * represents the bonding point to N in the pyrrole ring in the general formula (1), or to the adjacent Ar 1 ,Ar 2 ,Ar 5 or Ar 6 The key point of .

[0055] The photoelectric conversion element material preferably satisfies the following conditions: 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, the energy level of the lowest unoccupied molecular orbital (LUMO) obtained by the structure optimization calculation is -2.5 eV or more, and has a 1×10 -6 cm 2 / Vs or higher hole mobility, or being amorphous.

[0056] The photoelectric conversion element material can be used as a hole transport material of a photoelectric conversion element for imaging.

[0057] 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.

[0058] The photoelectric conversion element material may be contained in the electron blocking layer or the photoelectric conversion layer of the photoelectric conversion element, and in this case, it is preferably contained as a hole transport material. In addition, when the photoelectric conversion element material is contained in the electron blocking layer, the photoelectric conversion layer may be an electron transport material or contain a fullerene derivative.

[0059] Effects of the Invention

[0060] The photoelectric conversion element material for imaging of the present invention can achieve appropriate migration of holes or electrons in the photoelectric conversion element, 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. 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

[0061] [ Figure 1 ] is a cross-sectional schematic diagram showing a structural example of a photoelectric conversion element for imaging. DETAILED DESCRIPTION

[0062] 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 electric energy. The organic layer contains a material for the imaging photoelectric conversion element represented by any one of the general formula (1) or the general formula (2). Specifically, in the 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 material for the imaging photoelectric conversion element represented by any one of the general formula (1) or the general formula (2).

[0063] Hereinafter, the imaging photoelectric conversion element material represented by either of the general formula (1) or the general formula (2) is also referred to as a photoelectric conversion element material, a material of the present invention, or a compound represented by the general formula (1) or the general formula (2).

[0064] The compound represented by the general formula (1) or (2) is described below.

[0065] In the general formulae (1) and (2), each ring E independently represents a heterocyclic ring represented by the formula (1a) condensed with an adjacent ring at any position. The material of the present invention is preferably represented by the general formula (1).

[0066] X is composed of O, S, C(Ra)2 or N-(Ar 5 ) p -(Ar 6 ) q Represented by O, S or N-(Ar 5 ) p -(Ar 6 ) q express.

[0067] n, p and s represent the number of repetitions, n and p independently represent integers of 0 to 4, and s represents an integer of 1 to 4. n is preferably 0 to 2, and s is preferably 1 to 3. m and q independently represent the number of substitutions, and m and q independently represent integers of 1 to 3. m and q are preferably 1 to 2. When n is 0, m is 1, and when p is 0, q is 1.

[0068] Ar 1 ,Ar 2 ,Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 4 to 18 carbon atoms. 1 ,Ar 2 ,Ar 5 or Ar 6 At least one of, preferably Ar 1 ,Ar 2 ,Ar 5 and Ar 6 At least two of the above are represented by any one of formulas (3a) to (3d) in which the amine groups are further condensed and the diarylamine groups having 12 to 30 carbon atoms are substituted or unsubstituted, the arylheteroarylamine groups having 12 to 30 carbon atoms are substituted or unsubstituted, or the diheteroarylamine groups having 12 to 30 carbon atoms are substituted or unsubstituted. 1 or Ar 5 When the amino group in the group is further condensed, it is represented by formula (3a) or formula (3b), in which Ar 2 or Ar 6 When the amino group in the formula is further condensed to form a group, it is represented by formula (3c) or formula (3d). 1 In the case of multiple Ar 2 In the case of multiple Ar 5 The case where there are multiple Ar 6 The idea of ​​the case is as described above. 1 ,Ar 5 and Ar 6 The same is true.

[0069] Regarding the general formula (1), it is preferred to have a biphenyl group. The biphenyl group may be linked in the ortho position, the meta position or the para position, and is preferably p-biphenyl. Specifically, in the general formula (1), it is preferred to satisfy at least one of the following conditions (i), (ii), (iii), (iv), (v), (vi), (vii) or (viii), and more preferably to satisfy at least two of them.

[0070] Right now,

[0071] (i) When n=2 to 4, adjacent Ar 1 At least one group of them is phenyl, and they form a biphenyl group.

[0072] (ii) Adjacent Ar 1 with Ar 2 They are phenyl respectively and form biphenyl.

[0073] (iii) When p=2 to 4, adjacent Ar 5 At least one group of them is phenyl, and they form a biphenyl group.

[0074] (iv) Adjacent Ar 5 with Ar 6 They are phenyl respectively and form biphenyl.

[0075] (v) at least one Ar 1 It is a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group.

[0076] (vi) at least one Ar 2 It is a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group.

[0077] (vii) at least one Ar 5 It is a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group.

[0078] (viii) at least one Ar 6 It is a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms, and the aryl group of the amine group has at least one biphenyl group.

[0079] Examples of compounds satisfying the conditions of (i) or (iii) include (B1) and (B2), examples of compounds satisfying the conditions of (ii) or (iv) include (B40) and (B102), examples of compounds satisfying the conditions of (v) or (vii) include (B41) and (B103), and examples of compounds satisfying the conditions of (vi) or (viii) include (B29) and (B104), but are not limited to these. Compounds satisfying at least one of the conditions (i), (ii), (iii), (iv), (v), (vi), (vii) or (viii) are, for example, (B1) to (B5), (B25) to (B30), (B31), (B32), (B37), (B38), (B40), (B41), (B45) to (B49), (B50) to (B52), (B59), (B60), (B62), (B63), (B66), (B69) to (B74), (B75), (B76), (B77), (B78), (B79), (B80), (B81), (B82), (B83), (B84), (B85), (B86), (B87), (B88), (B89), (B90), (B91), (B92), (B93), (B94), (B95), (B96), (B97), (B98), (B99), (B100), (B101), (B102), (B103), (B104), (B105), (B106), (B107), (B108), (B110), (B111), (B112), (B113), (B114), (B115), (B116), (B117), (B118), (B119), (B12 B81), (B82), (B84), (B85), (B89), (B90), (B96), (B97), or (B102) to (B104), compounds satisfying at least two of the conditions (i), (ii), (iii), (iv), (v), (vi), (vii) or (viii) are, for example, (B1) to (B5), (B21), (B22), (B29) to (B30), (B49), (B73), (B74), or (B102) to (B104), but are not limited to them.

[0080] Specific examples of the group representing an unsubstituted diarylamine group having 12 to 30 carbon atoms, an unsubstituted arylheteroarylamine group having 12 to 30 carbon atoms, or an unsubstituted diheteroarylamine group having 12 to 30 carbon atoms include diphenylamine, dibenzylamine, phenylbenzylamine, phenylterbenzylamine, biphenylterbenzylamine, naphthylphenylamine, dinaphthylamine, dianthrylamine, diphenanthrylamine, phenylterphenylamine, biphenylterphenylamine, phenylcarbazolylphenylamine, phenylcarbazolylbenzylamine, biphenylcarbazolylphenylamine, bisphenylcarbazolylamine, dibenzofuranylphenylamine, dibenzofuranylbenzylamine, and bisdibenzofuranylamine. Preferred examples include: diphenylamine, dibenzidine, phenylbenzidine, naphthylphenylamine, dinaphthylamine, phenylcarbazolylphenylamine, phenylcarbazolylbenzidine, dibenzofuranylphenylamine, dibenzofuranylbenzidine. More preferred examples include: diphenylamine, phenylbenzidine, carbazolylphenylamine, carbazolylbenzidine, dibenzofuranylphenylamine, or dibenzofuranylbenzidine. As the aryl group constituting the amine group, an aryl group having 6 to 18 carbon atoms is preferred, and as the heteroaryl group, a heteroaryl group having 6 to 15 carbon atoms is preferred. The carbon number of these amine groups is preferably 12 to 27. In addition, as the heteroatom in the heteroaryl group, N, S or O is preferred.

[0081] In this specification, in the case of diarylamine, arylheteroarylamine and diheteroarylamine such as Ar 1 In the case of having two bonds, the nitrogen of the amine group and the carbon of the aryl or heteroaryl group serve as the bonding points.

[0082] Examples of the unsubstituted aromatic hydrocarbon compound having 6 to 30 carbon atoms 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, condensed tetraphenyl, and pleiadene, and pentacyclic aromatic hydrocarbons such as phenanthracene, perylene, pentaphene, condensed pentaphene, tetraphenylene, and naphthoanthracene. Preferably, it is benzene, naphthalene, anthracene, phenanthrene, triphenylene, or pyrene, and more preferably, it is a group derived from benzene, naphthalene, anthracene, and phenanthrene.

[0083] As unsubstituted heteroaromatic groups having 4 to 18 carbon atoms, for example, groups derived from nitrogen-containing aromatic compounds having a pyrrole ring, such as pyrrole, pyrrolopyrrole, indole, isoindole, pyrroloisoindole, and carboline, groups derived from thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, carbazole, phenylcarbazole, indolocarbazole, pyridine, pyrimidine, quinoline, isoquinoline, quinazoline, or quinoxaline can be exemplified. Preferably, thiophene, benzothiophene, dibenzothiophene, furan, benzofuran, dibenzofuran, carbazole, phenylcarbazole, or indolocarbazole is preferred, and groups derived from dibenzothiophene, dibenzofuran, carbazole, or phenylcarbazole are more preferred. 1 ,Ar 2 ,Ar 5 and Ar 6 In the case of a substituted or unsubstituted heteroaromatic group, the number of carbon atoms is preferably 6 to 18. 1 ,Ar 2 ,Ar 5 or Ar 6 Furthermore, at least one of them is preferably represented by a dibenzothiophenyl group, a dibenzofuranyl group, or a carbazolyl group.

[0084] In the present specification, examples of the substituent include deuterium, cyano, and an alkyl group having 1 to 20 carbon atoms.

[0085] When the substituent is an alkyl group having 1 to 20 carbon atoms, the alkyl group 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, tert-butyl, neopentyl, 2-ethylhexyl, and 2-hexyloctyl; and saturated alicyclic hydrocarbon groups such as cyclopentyl, cyclohexyl, cyclooctyl, 4-butylcyclohexyl, and 4-dodecylcyclohexyl.

[0086] In the present invention, a substituent is bonded to a carbon atom or a different atom constituting an aromatic ring.

[0087] Ar 3 and Ar 4and Ar respectively independently represent a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 4 to 18 carbon atoms. Examples of the unsubstituted diarylamino group having 12 to 30 carbon atoms, the arylheteroarylamino group having 12 to 30 carbon atoms, the diheteroarylamino group having 12 to 30 carbon atoms, the aromatic hydrocarbon group having 6 to 30 carbon atoms, and the heteroaromatic group having 4 to 18 carbon atoms include Ar 1 ,Ar 2 ,Ar 5 and Ar 6 The same as described in. Preferably, benzene, naphthalene, anthracene, phenanthrene, dibenzothiophene, dibenzofuran, carbazole or phenylcarbazole. 3 and Ar 4 In the case of a substituted or unsubstituted heteroaromatic group, the number of carbon atoms is preferably 6 to 18.

[0088] a and b represent the number of substitutions, and are each independently 0 to 3, preferably 0 to 2.

[0089] Y is each independently represented by a single bond, Si(Rb)2, C(Rb)2, O, S, Se or N-Rb, preferably represented by Si(Rb)2, C(Rb)2, O or S.

[0090] Ra and Rb each independently represent 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 4 to 18 carbon atoms. Examples of the unsubstituted alkyl group having 1 to 20 carbon atoms are the same as those described in the substituent group, and examples of the unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms and the unsubstituted heteroaromatic group having 4 to 18 carbon atoms are the same as those described in Ar. 1 ,Ar 2 ,Ar 5 and Ar 6 The same applies as described in . Preferably, it is an alkyl group having 1 to 10 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 18 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 6 to 18 carbon atoms.

[0091] Preferred specific examples of the photoelectric conversion element material represented by the general formula (1) or (2) of the present invention are shown below, but the present invention is not limited to these.

[0092] [Chemistry 3]

[0093]

[0094] [Chemistry 4]

[0095]

[0096] [Chemistry 5]

[0097]

[0098] [Chemistry 6]

[0099]

[0100] [Chemistry 7]

[0101]

[0102] [Chemistry 8]

[0103]

[0104] [Chemistry 9]

[0105]

[0106] [Chemistry 10]

[0107]

[0108] [Chemistry 11]

[0109]

[0110] [Chemistry 12]

[0111]

[0112] The photoelectric conversion element material of the present invention can be obtained by synthesizing 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 using a known method such as recrystallization, column chromatography, and sublimation purification, but is not limited to the above methods.

[0113] Regarding the photoelectric conversion element material 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 -4.5 eV or less, more preferably in the range of -4.8 eV to -6.0 eV.

[0114] The energy level of the lowest unoccupied molecular orbital (LUMO) obtained by the structural optimization calculation is preferably not less than -2.5 eV, more preferably in the range of -2.5 eV to -0.5 eV, and even more preferably in the range of -1.8 eV to -0.8 eV.

[0115] Regarding the photoelectric conversion element material of the present invention, the difference (absolute value) between the HOMO energy level and the LUMO energy level is preferably within a range of 2.0 eV to 5.0 eV, and more preferably within a range of 2.5 eV to 4.0 eV.

[0116] The photoelectric conversion element material of the present invention preferably has a 1×10 -6 cm 2 / Vs~1cm 2 / Vs, more preferably 2×10 -5 cm 2 / Vs~1×10 -1 cm 2 The 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.

[0117] 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).

[0118] 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.

[0119] Figure 1 1 is a cross-sectional view schematically showing the structure of an imaging photoelectric conversion element using the imaging photoelectric conversion element material of the present invention, 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 The structure can add or omit layers as needed. Figure 1In the opposite structure, the layers are stacked on the substrate 6 in the order of the electrode 5, the hole blocking layer 4, the photoelectric conversion layer 3, the electron blocking layer 2, and the electrode 1. In this case, layers may be added or omitted as needed. In the above-mentioned imaging photoelectric conversion element, the layers constituting the stacked structure on the substrate other than the electrodes such as the anode and the cathode are sometimes collectively referred to as organic layers.

[0120] Hereinafter, each member and each layer of the photoelectric conversion element of the present invention will be described.

[0121] -Substrate-

[0122] The photoelectric conversion element is preferably supported by a substrate. There are no particular limitations on the substrate, and for example, a substrate made of glass, transparent plastic, quartz, or the like can be used.

[0123] -electrode-

[0124] 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.

[0125] -Photoelectric conversion layer-

[0126] 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 having the function of absorbing light of a desired wavelength in the visible region. The P-type organic semiconductor material as a hole transport material can use the photoelectric conversion element material of the present invention.

[0127] As a P-type organic semiconductor material, any material having hole transport properties may be used, and the photoelectric conversion element material of the present invention is preferably used, but other P-type organic semiconductor materials may also be used. In addition, two or more compounds represented by the general formula (1) or the general formula (2) (photoelectric conversion element material of the present invention) may be mixed and used. Furthermore, the compound may also be mixed and used with other P-type organic semiconductor materials.

[0128] As other P-type organic semiconductor materials, any material having hole transport properties may be used, and examples thereof include naphthalene derivatives, anthracene derivatives, phenanthrene derivatives, pyrene derivatives, Derivatives, tetraphenyl derivatives, triphenylene derivatives, perylene derivatives, fluoranthene derivatives, fluorene derivatives, 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 and other aromatic compounds, aromatic amine derivatives, styrylamine derivatives, benzidine derivatives, porphyrin derivatives, phthalocyanine derivatives, or quinacridone derivatives.

[0129] 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 polyphenylene vinylene derivatives, polyparaphenylene derivatives, polyfluorene derivatives, polyvinyl carbazole derivatives, and polythiophene derivatives. In addition, two or more selected from the compounds represented by the general formula (1) or (2) of the present invention, the P-type organic semiconductor material, or the polymer type P-type organic semiconductor material can be used in combination.

[0130] 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 (fullerene derivatives), imidazole, thiazole, thiadiazole, oxazole, oxadiazole, triazole and other azole derivatives, etc. In addition, two or more materials selected from the N-type organic semiconductor materials may be mixed and used.

[0131] -Electron blocking layer-

[0132] 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 hole transporting the holes generated by the 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, preferably a compound represented by the general formula (1) or the general formula (2), and other P-type organic semiconductor materials can also be used. In addition, the compound represented by the general formula (1) or the general formula (2) can also be mixed with other P-type organic semiconductor materials or polymer-type P-type organic semiconductor materials as described above.

[0133] -Hole blocking layer-

[0134] 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. As the N-type organic semiconductor material, any material having electron transport properties may be used, and examples thereof include: polycyclic aromatic polycarboxylic acid anhydrides such as naphthalenetetracarboxylic acid diimide or perylenetetracarboxylic acid diimide or imides thereof, fullerenes such as C60 or C70 (fullerene derivatives), azole derivatives such as imidazole, thiazole, thiadiazole, oxazole, oxadiazole, and triazole, tris(8-hydroxyquinolinol)aluminum(III) derivatives, phosphine oxide derivatives, nitrosubstituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylmethane 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.

[0135] 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), general formula (2), general formula (3a) to general formula (3d), it also includes Ar 1 ,Ar 2 , Ra, Ar 3 ,Ar 4 , Rb, Ar 5 ,Ar 6 As a substituent such as , part or all of the hydrogen atoms on the aromatic ring may be deuterium.

[0136] 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.

[0137] 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.

[0138] The organic layer containing the photoelectric conversion element material of the present invention may be formed into a plurality of layers as necessary.

[0139] Example

[0140] Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

[0141] Calculation Example

[0142] Calculation of HOMO and LUMO

[0143] For the compound B1, compound B2, compound B3, compound B9, compound B61, compound B65 and compound B94, HOMO and LUMO were calculated. Furthermore, the calculation was performed using a calculation based on density functional theory (density functional theory (DFT: Density Functional Theory)), using Gaussian as a calculation program, and by a structure 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 a better HOMO and LUMO value.

[0144] For comparison, HOMO and LUMO were calculated for Compound H1, Compound H2, Compound H3, and Compound H4 by the same method as described above. The results are shown in Table 1.

[0145] [Chemistry 13]

[0146]

[0147] [Table 1]

[0148] Compound HOMO[eV] LUMO[eV] B1 -4.7 -1.0 B2 -4.7 -1.2 B3 -4.9 -1.2 B9 -4.7 -1.3 B61 -4.8 -0.8 B65 -4.9 -0.9 B94 -4.9 -1.0 H1 -4.9 -0.7 H2 -5.0 -1.3 H3 -5.3 -1.9 H4 -4.9 -0.8

[0149] The following are representative examples of the synthesis of compound B1, compound B2, compound B3, and compound B61. Other compounds were synthesized by similar methods.

[0150] Synthesis Example 1 (Synthesis of Compound B1)

[0151] [Chemistry 14]

[0152]

[0153] In a 200 ml three-necked flask that had been degassed and replaced with nitrogen, T1 (17.2 mmol), T2 (7.8 mmol), copper iodide (2.3 mmol), potassium carbonate (23.4 mmol), and 8-quinolinephenol (2.3 mmol) were placed, 40 ml of 1,3-dimethyl-2-imidazolidinone (DMI) was added, and the mixture was stirred at 190°C for 16 hours. After temporarily cooling to room temperature, 100 ml of water was added, and the resulting white precipitate was filtered out. The obtained residue was reprecipitated with xylene to obtain compound B1 (white solid). The yield was 31%. The obtained solid was evaluated by the XRD method, but no peak was detected. (APCI-TOFMS, m / z 895 [M+H] + )

[0154] Synthesis Example 2 (Synthesis of Compound B2)

[0155] [Chemistry 15]

[0156]

[0157] Compound B2 (white solid) was obtained in the same manner as in Synthesis Example 1 except that T1 was replaced by T3. The yield was 45%. The obtained solid was evaluated by XRD method, but no peak was detected. (APCI-TOFMS, m / z 995 [M+H] + )

[0158] Synthesis Example 3 (Synthesis of Compound B3)

[0159] [Chemistry 16]

[0160]

[0161] Compound B3 (white solid) was obtained in the same manner as in Synthesis Example 1 except that T1 was replaced by T4. The yield was 53%. The obtained solid was evaluated by XRD method, but no peak was detected. (APCI-TOFMS, m / z 975 [M+H] + )

[0162] Synthesis Example 4 (Synthesis of Compound B61)

[0163] [Chemistry 17]

[0164]

[0165] In a 200 ml three-necked flask that had been degassed and replaced with nitrogen, T5 (12.0 mmol), T6 (6.0 mmol), copper iodide (1.8 mmol), potassium carbonate (18.1 mmol), and 8-quinolinephenol (1.8 mmol) were placed, 1,3-dimethyl-2-imidazolidinone (DMI) 30 ml was added thereto, and the mixture was stirred at 190°C for 48 hours. After temporarily cooling to room temperature, 100 ml of water was added, and the resulting white precipitate was filtered out. The obtained residue was purified by column chromatography to obtain compound B61 (white solid). The yield was 66%. The obtained solid was evaluated by XRD method, but no peak was detected. (APCI-TOFMS, m / z 741 [M+H] + )

[0166] Determination of charge mobility

[0167] Compound B1 was deposited as an organic layer by vacuum deposition at a film thickness of about 3 μm on an electrode containing ITO with a film thickness of 110 nm formed on a glass substrate. Then, a device formed of 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 6.4×10 -4 cm 2 / Vs.

[0168] Physical property evaluation example

[0169] The hole mobility was measured in the same manner as above except that the compound B1 was replaced with the compounds shown in Table 2.

[0170] [Table 2]

[0171] Compound <![CDATA[Hole mobility [cm 2 / Vs]]]> B1 <![CDATA[6.4×10 -4 ]]> B2 <![CDATA[6.0×10 -4 ]]> B3 <![CDATA[3.6×10 -4 <!-- 23 -->]]> B9 <![CDATA[8.0×10 -4 ]]> B61 <![CDATA[2.4×10 -4 ]]> B65 <![CDATA[1.3×10 -4 ]]> B94 <![CDATA[7.1×10 -5 ]]> H3 <![CDATA[4.0×10 -5 ]]> H4 <![CDATA[9.3×10 -6 ]]>

[0172] Example 1

[0173] On an electrode including 70 nm thick ITO formed on a glass substrate, a vacuum of 4.0×10 -5 Pa formed a film of compound B1 with a thickness of 100 nm as an electron blocking layer. Then, a thin film of quinacridone 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 prepare a photoelectric conversion element.

[0174] A voltage of 2 V was applied between the ITO electrode and the aluminum electrode. The current in the dark at this time was 1.5×10 -10 A / cm 2 In addition, a voltage of 2 V was applied to irradiate light with a wavelength of 500 nm and a power of 1.6 μW / cm 2 The current when the ITO electrode side was irradiated with light was 1.4×10-7 A / cm 2 The light-dark ratio was calculated to be 9.3×10 2 .

[0175] Comparative Example 1

[0176] On an electrode including 70 nm thick ITO formed on a glass substrate, a vacuum of 4.0×10 -5 Pa formed a film of compound H1 with a thickness of 100 nm as an electron blocking layer. Then, quinacridone 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 prepare a photoelectric conversion element.

[0177] Table 3 shows the evaluation results of Example 1 and Comparative Example 1.

[0178] [Table 3]

[0179]

[0180] Example 2

[0181] On an electrode including 70 nm thick ITO formed on a glass substrate, a vacuum of 2.5×10 -5 Pa deposited compound B1 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 at 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 6.6×10 -10 A / cm 2 In 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 3.4×10 -7 A / cm 2 The light-dark ratio when 2.6V voltage is applied is 5.2×10 2 These results are shown in Table 4.

[0182] Embodiments 3 to 5

[0183] On an electrode including 70 nm thick ITO formed on a glass substrate, a vacuum of 2.5×10 -5Pa deposited compound B1 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 at 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 6.6×10 -10 A / cm 2 In 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 3.4×10 -7 A / cm 2 The light-dark ratio when 2.6V voltage is applied is 5.2×10 2 These results are shown in Table 4.

[0184] Comparative Examples 2 to 3

[0185] 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.

[0186] Table 4 shows the results of Examples 3 to 5 and Comparative Examples 2 to 3.

[0187] The compounds used in Examples and Comparative Examples are shown below.

[0188] [Chemistry 18]

[0189]

[0190] [Table 4]

[0191]

[0192] From the above results, it is clear that the compound of the present invention has a better light-dark ratio than the compound of the comparative example and is effectively used as a material for a photoelectric conversion element for imaging.

[0193] Explanation of symbols

[0194] 1: Electrode

[0195] 2: Hole blocking layer

[0196] 3: Photoelectric conversion layer

[0197] 4:Electron blocking layer

[0198] 5: Electrode

[0199] 6: Substrate

Claims

1. A material for a photoelectric conversion element for imaging, wherein: The photoelectric conversion element material for imaging is represented by the following general formula (1) or general formula (2): [Chemistry 1] In the general formula (1) and the general formula (2), ring E independently represents a heterocyclic ring represented by the formula (1a) which is condensed with an adjacent ring at any position; X represents O, S, C(Ra)2 or N-(Ar 5 ) p -(Ar 6 ) q ; Ar 1 ,Ar 2 ,Ar 5 and Ar 6 each independently represents a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted diheteroarylamino group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 4 to 18 carbon atoms; n, p and s represent the number of repetitions, n and p independently represent integers of 0 to 4, s represents an integer of 1 to 4; m and q independently represent the number of substitutions and represent integers of 1 to 3; wherein when n is 0, m is 1, and when p is 0, q is 1; Ra 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 4 to 18 carbon atoms; At least one Ar 1 ,Ar 2 ,Ar 5 or Ar 6 A substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamine group having 12 to 30 carbon atoms, a substituted or unsubstituted diheteroarylamine group having 12 to 30 carbon atoms, or any one of the following formulae (3a) to (3d) in which the amine group is further condensed; wherein in the group represented by Ar 1 or Ar 5 When the amino group in the above-mentioned is further condensed into a group, it is represented by the following formula (3a) or formula (3b), in which Ar 2 or Ar 6 When the amino group in is further condensed to form a group, it is represented by the following formula (3c) or formula (3d); [Chemistry 2] Y is independently represented by a single bond, Si(Rb)2, C(Rb)2, O, S, Se or N-Rb; Rb 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 4 to 18 carbon atoms; Ar 3 and Ar 4 Each independently represents a substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamine group having 12 to 30 carbon atoms, a substituted or unsubstituted diheteroarylamine group having 12 to 30 carbon atoms, a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaromatic group having 4 to 18 carbon atoms; a and b represent the number of substitutions and are independently 0 to 3; * represents a bonding point.

2. The material for a photoelectric conversion element for imaging according to claim 1, wherein X is composed of O, S or N-(Ar 5 ) p -(Ar 6 ) q express.

3. The material for a photoelectric conversion element for imaging according to claim 2, wherein: Ar 1 ,Ar 2 ,Ar 5 and Ar 6 At least one of the groups is represented by a substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms, a substituted or unsubstituted arylheteroarylamine group having 12 to 30 carbon atoms, or a substituted or unsubstituted diheteroarylamine group having 12 to 30 carbon atoms.

4. The material for a photoelectric conversion element for imaging according to claim 3, wherein Ar 1 ,Ar 2 ,Ar 5 and Ar 6 At least one of them is represented by a substituted or unsubstituted diarylamino group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamino group having 12 to 27 carbon atoms.

5. The material for a photoelectric conversion element for imaging according to claim 4, wherein Ar 1 ,Ar 2 ,Ar 5 and Ar 6 At least two of them are represented by a substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamine group having 12 to 27 carbon atoms.

6. The material for a photoelectric conversion element for imaging according to claim 1, wherein Ar 1 ,Ar 2 ,Ar 5 and Ar 6 At least one of the above formulas (3a) to (3d) is represented by any one of the above formulas, wherein Ar 1 and Ar 5 is selected from the formula (3a) or formula (3b), Ar 2 and Ar 6 Selected from formula (3c) or formula (3d).

7. The material for a photoelectric conversion element for imaging according to claim 1, wherein Y is represented by any one of Si(Rb)2, C(Rb)2, O or S.

8. The material for a photoelectric conversion element for imaging according to claim 1, wherein Ar 1 ,Ar 2 ,Ar 5 and Ar 6 At least two of them are represented by any one of the formulas (3a) to (3d), wherein Ar 1 are independently selected from the formula (3a) or formula (3b), Ar 2 Selected from formula (3c) or formula (3d).

9. The material for a photoelectric conversion element for imaging according to claim 1, wherein In the general formula (1), at least one of the following conditions (i), (ii), (iii), (iv), (v), (vi), (vii) or (viii) is satisfied: (i) When n=2 to 4, adjacent Ar 1 At least one group of them is phenyl, and they form a biphenyl group; (ii) Adjacent Ar 1 with Ar 2 are phenyl respectively, and form biphenyl; (iii) When p=2 to 4, adjacent Ar 5 At least one group of them is phenyl, and they form a biphenyl group; (iv) Adjacent Ar 5 with Ar 6 are phenyl respectively, and form biphenyl; (v) at least one Ar 1 is a substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamine group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group; (vi) at least one Ar 2 is a substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamine group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group; (vii) at least one Ar 5 is a substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamine group having 12 to 27 carbon atoms, and has at least one biphenyl group as the aryl group of the amine group; (viii) at least one Ar 6 It is a substituted or unsubstituted diarylamine group having 12 to 30 carbon atoms or a substituted or unsubstituted arylheteroarylamine group having 12 to 27 carbon atoms, and the aryl group of the amine group has at least one biphenyl group.

10. The material for a photoelectric conversion element for imaging according to claim 9, wherein In the general formula (1), at least two of the conditions (i) to (viii) are satisfied.

11. The material for a photoelectric conversion element for imaging according to claim 1, wherein Ar 1 ,Ar 2 ,Ar 5 or Ar 6 At least one of them is a carbazolyl group, a dibenzofuranyl group or a dibenzothiophenyl group.

12. 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.

13. The material for a photoelectric conversion element for imaging according to claim 1, wherein: The energy level of the lowest unoccupied molecular orbital (LUMO) obtained by structure optimization calculation based on density functional calculation B3LYP / 6-31G(d) is above -2.5 eV.

14. The material for a photoelectric conversion element for imaging according to claim 1, wherein: The photoelectric conversion element material for imaging has a 1×10 -6 cm 2 / Vs and above hole mobility.

15. The material for a photoelectric conversion element for imaging according to claim 1, wherein The material for the imaging photoelectric conversion element is amorphous.

16. The material for a photoelectric conversion element for imaging according to claim 1, wherein: The material for an imaging photoelectric conversion element is used as a hole transport material of an imaging photoelectric conversion device.

17. A photoelectric conversion element for imaging, comprising a photoelectric conversion layer and an electron blocking layer between two electrodes, wherein 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.

Images