JP2015065267A - Material for organic thin film solar battery elements, and use thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a material for photoelectric conversion elements which enables a film formation by deposition or spin coating and allows a high photoelectric conversion efficiency to be achieved when used for a photoelectric conversion element.SOLUTION: A material for organic thin film solar battery elements comprises a compound expressed by the general formula below. [General formula] (In the formula, X represents -O- or -S-; and Rto Rrepresent a substituent group.)

Description

  The present invention relates to a novel material for an organic thin film solar cell element (hereinafter abbreviated as a photoelectric conversion element) and its use. More specifically, when used in a photoelectric conversion element, it can be formed by vapor deposition or spin coating, and exhibits excellent performance (high photoelectric conversion efficiency), and can be suitably used particularly for a photoelectric conversion material. The present invention relates to a material for a photoelectric conversion element.

  In recent years, photoelectric conversion elements are attracting attention because they are a clean energy-saving source that can directly convert sunlight into electric power and that does not generate harmful gases at all in the process of power generation. Until now, silicon and compound semiconductors have been developed and put to practical use. Among them, silicon-based materials require high-purity silicon in the manufacturing process, the manufacturing process consists of a high-temperature process, and considering the energy required for manufacturing, the photoelectric conversion element does not necessarily contribute sufficiently to energy-saving technology. I could not say. In addition, these devices are characterized by their characteristics of being hard and fragile. Furthermore, a high temperature process is required, and it is a necessary condition to use glass for the substrate.

With recent technological developments, to solve these problems, solar cells using organic materials that can be expected to save energy during manufacturing and that can be applied to processes that require a large area without using high-temperature processes (application) are attracting attention. Has been. (Patent Document 1) Furthermore, since a device can be manufactured at a low temperature, it is possible to use a plastic or the like as a base material, and it is possible to realize a lightweight and flexible device, and a new application is expected.

  In organic thin-film solar cell elements, high photoelectric conversion efficiency and long life are required. The practical application of organic thin-film solar cells with an element structure in which an organic p-type semiconductor such as benzoporphyrin, phthalocyanine, or a conjugated polymer and a thin film composed of an organic n-type semiconductor such as perylene diimide or fullerene derivative are sandwiched between photoelectric conversion layers However, at present, the photoelectric conversion efficiency is still as low as 2 to 3%, and further improvement in efficiency is an issue. On the other hand, as a means for solving the photoelectric conversion efficiency improvement of the organic thin film solar cell, for example, (Non-Patent Document 1) reports diceropyrrolopyrrole as a latent pigment in addition to porphyrin and phthalocyanine derivatives as organic semiconductor materials. Yes. (Non-Patent Document 2)

  Among them, as for the diceropyrrolopyrrole derivative containing a furan ring, many polymer materials have been reported when attention is paid to a compound containing a furan ring, which is considered to have a long absorption wavelength. (Non-Patent Documents 3 to 7) However, in the case of a polymer material, the lifetime of the device is short, and there is a drawback that it is difficult to say that it is a practical material.

  Moreover, a low molecular weight material is disclosed as a diceropyrrolopyrrole derivative containing a furan ring. (Patent Document 2) However, since there is no substituent on the N atom (see compound (A) in the examples of the present application), the absorption wavelength is short and the crystallinity is high, so that the lifetime of the device is short and practical. There was a drawback that it was difficult to use the material.

  Also disclosed is a polymer derivative of diceropyrrolopyrrole containing a thiophene ring. (Patent Document 3) However, all have shortcomings that the lifetime of the element is short and it is difficult to say that it is a practical material.

  In addition, a diceropyrrolopyrrole derivative containing a thiophene ring is disclosed (Patent Document 4). However, there is no patent document describing a diceropyrrolopyrrole derivative containing a furan ring.

  In general, an organic device has a characteristic that the organic material itself deteriorates due to external factors such as heat, light, moisture, oxygen, and the life is shorter than that of an inorganic device. Furthermore, the photoelectric conversion element needs to improve the photoelectric conversion efficiency for practical use.

  In addition, since the photoelectric conversion material is generally used as a thin film, the temporal stability of the thin film greatly affects the lifetime of the device. Furthermore, in order to apply the coating process, high solubility is required for general-purpose solvents.

JP 2004-335737 A JP 2010-192782 JP JP 2009-541548 JP 2011-501743 A

Yutaka Matsuo Science of organic thin-film solar cells J.S.Zambounis, Z.Hao, A.Iqbal, Nature, 388,131 (1997) Phys. Chem. Chem. Phys., 2012, 14, 7162-7169 J. Mater. Chem., 2012, 22, 4425-4435 J. Mater. Chem., 2011, 21, 1600-1606 J.Am.Chem.Soc.2010,132,15547-15549 J.Am.Chem.Soc. 2012,134,2180-2185

  An object of the present invention is to provide a compound having diketopyrrolopyrrole as a basic skeleton that is useful as a material for a photoelectric conversion element, can be deposited and formed into a film, and exhibits high photoelectric conversion efficiency. is there.

  As a result of intensive studies to solve the above problems, the present inventors have arrived at the present invention.

（式中、Ｘは、−Ｏ−、または、−Ｓ−を表し、
Ｒ¹およびＲ²は、それぞれ独立に、置換もしくは未置換の脂肪族炭化水素基、置換もしくは未置換のアルコキシカルボニル基、または、置換もしくは未置換のアリ−ルオキシカルボニル基を表し、
Ｒ³〜Ｒ⁵は、それぞれ独立に、水素原子、ハロゲン原子、置換もしくは未置換の脂肪族炭化水素基、置換もしくは未置換の芳香族炭化水素基、置換もしくは未置換の脂肪族複素環基、置換もしくは未置換の芳香族複素環基、置換シリル基、シアノ基、置換もしくは未置換のアルコキシル基、置換もしくは未置換のアリ−ルオキシ基、置換アミノ基、または、下記一般式［３］で表される基を表す。ただし、Ｒ³〜Ｒ⁵の少なくとも１つは下記一般式［３］で表される基である。
Ｒ⁶〜Ｒ⁸は、それぞれ独立に、水素原子、ハロゲン原子、置換もしくは未置換の脂肪族炭化水素基、置換もしくは未置換の芳香族炭化水素基、置換もしくは未置換の脂肪族複素環基、置換もしくは未置換の芳香族複素環基、置換シリル基、シアノ基、置換もしくは未置換のアルコキシル基、置換もしくは未置換のアリ−ルオキシ基、置換アミノ基、または、下記一般式［４］で表される基を表す。ただし、Ｒ⁶〜Ｒ⁸の少なくとも１つは下記一般式［４］で表される基である。）
一般式［２］

（式中、Ｘは、−Ｏ−、または、−Ｓ−を表し、
Ｒ⁹およびＲ¹⁰は、それぞれ独立に、置換もしくは未置換の脂肪族炭化水素基、置換もしくは未置換のアルコキシカルボニル基、または、置換もしくは未置換のアリ−ルオキシカルボニル基を表し、
Ｒ¹¹〜Ｒ¹³は、それぞれ独立に、水素原子、ハロゲン原子、置換もしくは未置換の脂肪族炭化水素基、置換もしくは未置換の芳香族炭化水素基、置換もしくは未置換の脂肪族複素環基、置換もしくは未置換の芳香族複素環基、置換シリル基、シアノ基、置換もしくは未置換のアルコキシル基、置換もしくは未置換のアリ−ルオキシ基、置換アミノ基、または、下記一般式［３］で表される基を表す。ただし、Ｒ¹¹〜Ｒ¹³の少なくとも１つは下記一般式［３］で表される基である。
Ｒ¹⁴〜Ｒ¹⁶は、それぞれ独立に、水素原子、ハロゲン原子、置換もしくは未置換の脂肪族炭化水素基、置換もしくは未置換の芳香族炭化水素基、置換もしくは未置換の脂肪族複素環基、置換もしくは未置換の芳香族複素環基、置換シリル基、シアノ基、置換もしくは未置換のアルコキシル基、置換もしくは未置換のアリ−ルオキシ基、置換アミノ基、または、下記一般式［４］で表される基を表す。ただし、Ｒ¹⁴〜Ｒ¹⁶の少なくとも１つは下記一般式［４］で表される基である。）
一般式［３］

（式中、Ｙは、直接結合、置換もしくは未置換の２価の芳香族炭化水素基、または、置換もしくは未置換の２価の芳香族複素環基を表す。）
一般式［４］

（式中、Ｚは、直接結合、置換もしくは未置換の２価の芳香族炭化水素基、または、置換もしくは未置換の２価の芳香族複素環基を表し、
Ｒ¹⁷〜Ｒ²⁶は、それぞれ独立に、水素原子、ハロゲン原子、置換もしくは未置換の脂肪族炭化水素基、置換もしくは未置換の芳香族炭化水素基、置換もしくは未置換の脂肪族複素環基、置換もしくは未置換の芳香族複素環基、置換シリル基、シアノ基、置換もしくは未置換のアルコキシル基、置換もしくは未置換のアリ−ルオキシ基、または、置換アミノ基を表し、Ｒ¹⁷〜Ｒ²¹、Ｒ²²〜Ｒ²⁶、および、Ｒ²¹とＲ²²は、隣り合う置換基どうしで環を形成しても良い。） That is, the present invention relates to a material for an organic thin film solar cell element comprising a compound represented by the following general formula [1] and / or a compound represented by the following general formula [2].
General formula [1]

(In the formula, X represents -O- or -S-,
R ¹ and R ² each independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or a substituted or unsubstituted aryloxycarbonyl group;
R ^{3 to} R ⁵ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or the following general formula [3] Represents a group. However, at least one of R ^{3 to} R ⁵ is a group represented by the following general formula [3].
R ^{6 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or the following general formula [4] Represents a group. However, at least one of R ^{6 to} R ⁸ is a group represented by the following general formula [4]. )
General formula [2]

(In the formula, X represents -O- or -S-,
R ⁹ and R ¹⁰ each independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or a substituted or unsubstituted aryloxycarbonyl group;
R ^{11 to} R ¹³ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or the following general formula [3] Represents a group. However, at least one of R ^{11 to} R ¹³ is a group represented by the following general formula [3].
R ^{14 to} R ¹⁶ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or the following general formula [4] Represents a group. However, at least one of R ^{14 to} R ¹⁶ is a group represented by the following general formula [4]. )
General formula [3]

(In the formula, Y represents a direct bond, a substituted or unsubstituted divalent aromatic hydrocarbon group, or a substituted or unsubstituted divalent aromatic heterocyclic group.)
General formula [4]

(In the formula, Z represents a direct bond, a substituted or unsubstituted divalent aromatic hydrocarbon group, or a substituted or unsubstituted divalent aromatic heterocyclic group,
R ^{17 to} R ²⁶ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, or a substituted amino group, R ^{17 to} R ²¹ , R ^{22 to} R ²⁶ , and R ²¹ and R ²² may form a ring with adjacent substituents. )

  Further, the present invention provides an organic thin film solar cell element in which an organic layer including a photoelectric conversion layer is formed between a pair of electrodes, wherein the photoelectric conversion layer includes the organic thin film solar cell element material. The present invention relates to a battery element.

  Moreover, this invention relates to the said organic thin film solar cell element characterized by including a fullerene derivative as a n-type semiconductor material in a photoelectric converting layer.

  Moreover, this invention relates to the said organic thin film solar cell element characterized by including an inorganic semiconductor as a n-type semiconductor material in a photoelectric converting layer.

  Moreover, this invention relates to the organic thin-film solar cell element in any one of Claims 4-6 in which a photoelectric converting layer is formed into a film by application | coating.

  Moreover, this invention relates to the ink composition for organic thin film solar cell elements which consists of the said organic thin film solar cell element material and an organic solvent.

  A photoelectric conversion element using the photoelectric conversion element material of the present invention exhibits high photoelectric conversion efficiency and has a long lifetime, and therefore can be used as a power source for a display board and a marker lamp.

  Hereinafter, the present invention will be described in detail.

First, R ¹ and R ² in the general formula [1] and R ⁹ and R ¹⁰ in the general formula [2] are each independently a substituted or unsubstituted aliphatic hydrocarbon group, substituted or unsubstituted alkoxy. A carbonyl group or a substituted or unsubstituted aryloxycarbonyl group is represented.

The aliphatic hydrocarbon group for R ¹ and R ² , and R ⁹ and R ¹⁰ refers to an aliphatic hydrocarbon group having 1 to 18 carbon atoms, such as an alkyl group, an alkenyl group, an alkynyl group. Group and a cycloalkyl group.

  Here, as the alkyl group, methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, pentyl group, isopentyl group, hexyl group, heptyl group, octyl group , An alkyl group having 1 to 18 carbon atoms such as a decyl group, a dodecyl group, a pentadecyl group, and an octadecyl group.

  Examples of the alkenyl group include vinyl group, 1-propenyl group, 2-propenyl group, isopropenyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1-octenyl group, 1-decenyl group, 1 -C2-C18 alkenyl groups, such as an octadecenyl group, are mentioned.

  Examples of the alkynyl group include ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 3-butynyl group, 1-octynyl group, 1-decynyl group and 1-octadecynyl group. Examples include alkynyl groups having 2 to 18 carbon atoms.

  Examples of the cycloalkyl group include cycloalkyl groups having 3 to 18 carbon atoms such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, and a cyclooctadecyl group.

The alkoxycarbonyl group in R ¹ and R ² and R ⁹ and R ¹⁰ is preferably an alkoxycarbonyl group having 2 to 14 carbon atoms. Examples of such include, but are not limited to, the following examples: methoxycarbonyl group, ethoxycarbonyl group, and benzyloxycarbonyl group.

As the aryloxycarbonyl group for R ¹ and R ² , and R ⁹ and R ^10, an aryloxycarbonyl group having 2 to 14 carbon atoms is preferable. As such, although not limited to the following examples, a phenoxycarbonyl group and a naphthyloxycarbonyl group are exemplified.

Next, R ^{3 to} R ⁵ in the general formula [1] are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, substituted or An unsubstituted aliphatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or Represents a group represented by the general formula [3]. However, at least one of R ^{3 to} R ⁵ is a group represented by the general formula [3].
R ^{6 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or a general formula [4] Represents a group. However, at least one of R ^{6 to} R ⁸ is a group represented by the general formula [4].

In the general formula [2], R ^{11 to} R ¹³ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted group. A substituted aliphatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or The group represented by General Formula [3] is represented. However, at least one of R ^{11 to} R ¹³ is a group represented by the general formula [3].
R ^{14 to} R ¹⁶ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or a general formula [4] Represents a group. However, at least one of R ^{14 to} R ¹⁶ is a group represented by the general formula [4].

Examples of the halogen atom in R ^{3 to} R ⁸ and R ^{11 to} R ¹⁶ include a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom.

The aliphatic hydrocarbon group for R ^{3 to} R ⁸ and R ^{11 to} R ¹⁶ has the same meaning as the aliphatic hydrocarbon group for R ¹ and R ² .

Examples of the aromatic hydrocarbon group in R ^{3 to} R ⁸ and R ^{11 to} R ¹⁶ include a single ring, a condensed ring, and a ring assembly hydrocarbon group.

  Here, the monocyclic aromatic hydrocarbon group has 6 carbon atoms such as phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, 2,4-xylyl group, p-cumenyl group and mesityl group. -18 monocyclic aromatic hydrocarbon groups.

  Examples of the condensed ring hydrocarbon group include 1-naphthyl group, 2-naphthyl group, 1-anthryl group, 2-anthryl group, 5-anthryl group, 1-phenanthryl group, 9-phenanthryl group, 1-acenaphthyl group, Examples thereof include condensed ring hydrocarbon groups having 10 to 18 carbon atoms such as 2-azurenyl group, 1-pyrenyl group and 2-triphenylyl group.

  Examples of the ring assembly hydrocarbon group include ring assembly hydrocarbon groups having 12 to 18 carbon atoms such as an o-biphenylyl group, an m-biphenylyl group, and a p-biphenylyl group.

Examples of the aliphatic heterocyclic group represented by R ^{3 to} R ⁸ and R ^{11 to} R ¹⁶ include an aliphatic heterocyclic group having 3 to 18 carbon atoms such as a 2-pyrazolino group, a piperidino group, a morpholino group, and a 2-morpholinyl group. Can be mentioned.

Examples of the aromatic heterocyclic group in R ^{3 to} R ⁸ and R ^{11 to} R ¹⁶ include a triazolyl group, a 3-oxadiazolyl group, a 2-furanyl group, a 3-furanyl group, a 2-furyl group, a 3-furyl group, 2-thienyl group, 3-thienyl group, 1-pyrrolyl group, 2-pyrrolyl group, 3-pyrrolyl group, 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, 2-pyrazyl group 2-oxazolyl group, 3-isoxazolyl group, 2-thiazolyl group, 3-isothiazolyl group, 2-imidazolyl group, 3-pyrazolyl group, 2-quinolyl group, 3-quinolyl group, 4-quinolyl group, 5-quinolyl group 6-quinolyl group, 7-quinolyl group, 8-quinolyl group, 1-isoquinolyl group, 2-quinoxalinyl group, 2-benzofuryl group, 2-benzothienyl group, N-indolyl group, N-carbazolyl And an aromatic heterocyclic group having 2 to 18 carbon atoms such as a group, N-acridinyl group, 2-thiophenyl group, 3-thiophenyl group, bipyridyl group, and phenanthroyl group.

The substituted silyl group in R ^{3 to} R ⁸ and R ^{11 to} R ¹⁶ is a substituted or unsubstituted alkyl group, or a silyl group substituted by a substituted or unsubstituted aryl group, and a monoalkylsilyl group And substituted silyl groups such as monoarylsilyl group, dialkylsilyl group, diarylsilyl group, trialkylsilyl group, triarylsilyl group and the like.

  Here, as the monoalkylsilyl group, a monoalkylsilyl group such as a monomethylsilyl group, a monoethylsilyl group, a monobutylsilyl group, a monoisopropylsilyl group, a monodecanesilyl, a monoicosanesilyl group, or a monotriacontanesilyl group Is mentioned.

  Examples of the monoarylsilyl group include monoarylsilyl such as monophenylsilyl group, monotolylsilyl group, mononaphthylsilyl group, and monoanthrylsilyl group.

  Examples of the dialkylsilyl group include dialkylsilyl groups such as dimethylsilyl group, diethylsilyl group, dimethylethylsilyl group, diisopropylsilyl group, dibutylsilyl group, dioctylsilyl group, and didecanesilyl group.

  Examples of the diarylsilyl group include diarylsilyl such as diphenylsilyl group and ditolylsilyl group.

  Examples of the trialkylsilyl group include trialkylsilyl groups such as trimethylsilyl group, triethylsilyl group, dimethylethylsilyl group, triisopropylsilyl group, tributylsilyl group, and trioctylsilyl group.

  Examples of the triarylsilyl group include triarylsilyl groups such as a triphenylsilyl group and a tolylsilylsilyl group.

Examples of the alkoxyl group in R ^{3 to} R ⁸ and R ^{11 to} R ¹⁶ include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a tert-butoxy group, an octyloxy group, and a tert-octyloxy group. 8 alkoxyl groups.

As an aryloxy group in R ^{3 to} R ⁸ and R ^{11 to} R ¹⁶ , a phenoxy group, a 4-tert-butylphenoxy group, a 1-naphthyloxy group, a 2-naphthyloxy group, a 9-anthryloxy group And an aryloxy group having 6 to 14 carbon atoms.

Examples of the substituted amino group in R ^{3 to} R ⁵ and R ^{11 to} R ¹⁶ include N-methylamino group, N-ethylamino group, N, N-diethylamino group, N, N-diisopropylamino group, N, N -Dibutylamino group, N-benzylamino group, N, N-dibenzylamino group, N-phenylamino group, N-phenyl-N-methylamino group, N, N-diphenylamino group, N, N-bis ( m-tolyl) amino group, N, N-bis (p-tolyl) amino group, N, N-bis (p-biphenylyl) amino group, bis [4- (4-methyl) biphenylyl] amino group, N-α Examples thereof include substituted amino groups having 2 to 26 carbon atoms such as naphthyl-N-phenylamino group and N-β-naphthyl-N-phenylamino group.

  Y in the general formula [3] represents a substituted or unsubstituted divalent aromatic hydrocarbon group, a substituted or unsubstituted divalent aromatic heterocyclic group, a combination thereof, or a direct bond.

Examples of the divalent aromatic hydrocarbon group for Y include a divalent group formed by removing one hydrogen atom from the aromatic hydrocarbon group described in R ^{3 to} R ⁸ in the general formula [1]. it can.

Examples of the divalent aromatic heterocyclic group for Y include a divalent group formed by removing one hydrogen atom from the aromatic heterocyclic group described in R ^{3 to} R ⁸ in the general formula [1]. it can.

Next, Z in the general formula [4] represents a substituted or unsubstituted divalent aromatic hydrocarbon group, a substituted or unsubstituted divalent aromatic heterocyclic group, a combination thereof, or a direct bond. Represent,
R ^{17 to} R ²⁶ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, or a substituted amino group, R ^{17 to} R ²¹ , R ^{22 to} R ²⁶ , and R ²¹ and R ²² may form a ring with adjacent substituents.

Examples of the divalent aromatic hydrocarbon group in Z include a divalent group formed by removing one hydrogen atom from the aromatic hydrocarbon group described in R ^{3 to} R ⁸ in the general formula [1]. it can.

Examples of the divalent aromatic heterocyclic group in Z include a divalent group formed by removing one hydrogen atom from the aromatic heterocyclic group described in R ^{3 to} R ⁸ in the general formula [1]. it can.

The halogen atom in R ^{17 to} R ²⁶ has the same meaning as the halogen atom in R ^{3 to} R ⁸ .

The aliphatic hydrocarbon group for R ^{17 to} R ²⁶ has the same meaning as the aliphatic hydrocarbon group for R ¹ and R ² .

The aromatic hydrocarbon group for R ^{17 to} R ²⁶ has the same meaning as the aromatic hydrocarbon group for R ^{3 to} R ⁸ .

The aliphatic heterocyclic group for R ^{17 to} R ²⁶ has the same meaning as the aliphatic heterocyclic group for R ^{3 to} R ⁸ .

The aromatic heterocyclic group for R ^{17 to} R ²⁶ has the same meaning as the aromatic heterocyclic group for R ^{3 to} R ⁸ .

The substituted silyl group for R ^{17 to} R ²⁶ has the same meaning as the substituted silyl group for R ^{3 to} R ⁸ .

The alkoxyl group for R ¹⁷ to R ^26, the same meaning as alkoxy group in R ³ to R ^8.

The aryloxy group for R ^{17 to} R ²⁶ has the same meaning as the aryloxy group for R ^{3 to} R ⁸ .

The substituted amino group for R ^{17 to} R ²⁶ has the same meaning as the substituted amino group for R ^{3 to} R ⁸ .

  These, aliphatic hydrocarbon group, alkoxycarbonyl group, aryloxycarbonyl group, aromatic hydrocarbon group, aliphatic heterocyclic group, aromatic heterocyclic group, alkoxyl group, aryloxy group, divalent aromatic The hydrocarbon group and the divalent aromatic heterocyclic group may be further substituted with other substituents. Examples of such a substituent include the above-described aliphatic hydrocarbon group, aromatic hydrocarbon group, aliphatic heterocyclic group, and aromatic heterocyclic group.

  The compound represented by the general formula [1] and the compound represented by the general formula [2] have been described above. When producing a photoelectric conversion element by vapor deposition using these compounds as a photoelectric conversion element material, the molecular weight of the photoelectric conversion element material is preferably 1500 or less, more preferably 1200 or less, still more preferably 1000 or less, and further preferably 800 or less. Is particularly preferred. This is because, when the molecular weight is large, there is a concern that it is difficult to produce an element by vapor deposition.

  However, this is not the case when a photoelectric conversion element is formed by a coating method. In this case, the solubility in the solvent used and the amorphous nature of the coating film are more important than the molecular weight.

More specifically, in the photoelectric conversion element material of the present invention, the substituent (specific examples: R ¹ and R ² , R ⁶ and R ⁷ ) is a hydrogen atom on the N atom of the diketopyrrolopyrrole ring. In addition, the solubility in a coating solvent is reduced by intermolecular hydrogen bonding, and it becomes difficult to produce a photoelectric conversion element by coating.

  Although the typical example of the material for photoelectric conversion elements of this invention is shown in the following Table 1, this invention is not limited to this representative example.

  Examples of n-type semiconductors in the present invention include fullerene (C60, C70, C76, etc.) compounds; octaazaporphyrins, perfluoro compounds of the above p-type semiconductors, naphthalenetetracarboxylic anhydride, naphthalenetetracarboxylic acid diimide, perylene Examples thereof include aromatic carboxylic acid anhydrides such as tetracarboxylic acid anhydride and perylene tetracarboxylic acid diimide and imidized products thereof; and derivatives containing these compounds as a skeleton. Among them, a fullerene compound is preferable, and a fullerene compound to which indenes are added is more preferable. The fullerene compound to which indene is added is not particularly limited, and examples thereof include those described in International Publication No. 2008/018931.

  Next, representative examples of fullerene derivatives used as n-type semiconductors are shown in Table 2 below, but the present invention is not limited to these representative examples.

  Next, representative examples of inorganic semiconductors used as n-type semiconductors are shown in Table 3 below, but the present invention is not limited to these representative examples.

  The inorganic semiconductor used as the n-type semiconductor can be used in a single crystal, polycrystal, amorphous, or a mixed state thereof. From the viewpoint of photoelectric conversion efficiency, single crystals and polycrystals with high electron mobility are preferable, and single crystals are particularly preferable.

  Next, as examples of p-type semiconductors, porphyrin compounds such as tetrabenzoporphyrin, tetrabenzocopper porphyrin, tetrabenzozinc porphyrin, phthalocyanine compounds such as phthalocyanine, copper phthalocyanine, zinc phthalocyanine, naphthalocyanine compounds, tetracene and pentacene polyacene, sexi Examples include oligothiophenes such as thiophene and derivatives containing these compounds as a skeleton. Furthermore, polymers such as polythiophene, polyfluorene, polyphenylene vinylene, polytriallylamine, polyacetylene, polyaniline, polypyrrole and the like including poly (3-alkylthiophene) can also be used.

The photoelectric conversion layer contains an n-type semiconductor and a p-type semiconductor. As long as at least a p-type semiconductor and an n-type semiconductor are contained, the specific configuration of the photoelectric conversion layer is arbitrary. That is, the photoelectric conversion layer may be constituted by only a single layer film or may be constituted by two or more laminated films. For example, the n-type semiconductor and the p-type semiconductor may be contained in separate films, or the n-type semiconductor and the p-type semiconductor may be contained in the same film. Each of the n-type semiconductor and the p-type semiconductor may be composed of one kind of semiconductor material, and any two or more kinds of semiconductor materials may be used in an arbitrary ratio.

  As a specific example, the photoelectric conversion layer may be a bulk heterojunction type having a layer (i layer) in which a p-type semiconductor and an n-type semiconductor are phase-separated within the layer. The photoelectric conversion layer may be a stacked type (hetero pn junction type) having an interface between a layer containing a p-type semiconductor (p layer) and a layer containing an n-type semiconductor (n layer). Further, the photoelectric conversion layer may be a Schottky type or a combination of the above types. Among these, a bulk heterojunction type, and a combination of a bulk heterojunction type and a stacked type (p-i-n junction type) are preferable because they exhibit high performance.

  Although there is no restriction | limiting in the thickness of each layer of p layer of a photoelectric converting layer, i layer, and n layer, Preferably it is 3 nm or more, More preferably, it is 10 nm or more, Preferably it is 200 nm or less, More preferably, it is 100 nm or less. By increasing the layer thickness, the uniformity of the film tends to increase. Further, by reducing the layer thickness, the transmittance is improved and the series resistance tends to decrease.

The electrode can be formed of any material having conductivity. Examples of electrode materials include metals such as platinum, gold, silver, aluminum, chromium, nickel, copper, titanium, magnesium, calcium, barium, sodium, and alloys thereof; metal oxides such as indium oxide and tin oxide Or conductive alloys such as these alloys (ITO), polyaniline, polypyrrole, polythiophene, polyacetylene, etc., and acids such as hydrochloric acid, sulfuric acid, sulfonic acid, Lewis acids such as FeCI ₃ , iodine, etc. Examples include metal particles containing dopants such as metal atoms such as halogen atoms, sodium and potassium, and conductive composite materials in which conductive particles such as carbon black, fullerene and carbon nanotubes are dispersed in a matrix such as a polymer binder. It is done. Among them, a material having a high work function such as Au and ITO is preferable for the electrode for collecting holes. On the other hand, for the electrode for collecting electrons, a material having a low work function such as Al is preferable. By optimizing the work function, holes and electrons generated by light absorption can be collected well.

  In the present invention, the wet film forming method is a coating method, an inkjet method, a dip coating method, a die coating method, a spray coating method, a spin coating method, a roll coater method, a dipping coating method, a screen printing method, flexographic printing, The composition is applied to form a film by a screen printing method, an LB method, or the like.

  High-purity materials are required for materials for photoelectric conversion elements, but the compounds of the present invention can be obtained by sublimation purification method, recrystallization method, reprecipitation method, zone melting method, column purification method, adsorption method, etc. A combination of methods can be performed. Of these purification methods, the recrystallization method is preferred. For compounds having sublimation properties, it is preferable to employ a sublimation purification method. In the sublimation purification, it is preferable to employ a method in which the sublimation boat is maintained at a temperature lower than the temperature at which the target compound sublimates, and the sublimation impurities are removed in advance. In addition, it is desirable to apply a temperature gradient to the portion where the sublimate is collected so that the sublimate is dispersed in the impurities and the target product. Sublimation purification as described above is purification that separates impurities, and can be applied to the present invention. In addition, sublimation purification is useful for predicting the difficulty of the material vapor deposition.

  Next, the ink composition for photoelectric conversion elements will be described.

  The ink composition for photoelectric conversion elements in the present invention contains at least the material for photoelectric conversion elements of the present invention and a solvent.

  Various solvents are applicable as the solvent contained in the above-described ink composition for photoelectric conversion elements, and are not particularly limited. For example, aromatic hydrocarbons such as toluene, xylene, methicylene, cyclohexylbenzene, and tetralin. Halogenated aromatic hydrocarbons such as chlorobenzene, dichlorobenzene, and trichlorobenzene. Aromatics such as 1,2-dimethoxybenzene, 1,3-dimethoxybenzene, anisole, phenetole, 2-methoxytoluene, 3-methoxytoluene, 4-methoxytoluene, 2,3-dimethylanisole, 2,4-dimethylanisole ether. Aromatic esters such as phenyl acetate, phenyl propionate, methyl benzoate, ethyl benzoate, propyl benzoate, and n-butyl benzoate. Ketone having an alicyclic ring such as cyclohexanone or cyclooctanone. Aliphatic ketones such as methyl ethyl ketone and dibutyl ketone. Alcohol having an alicyclic ring such as methyl ethyl ketone, cyclohexanol or cyclooctanol. Aliphatic alcohols such as butanol and hexanol. Aliphatic ethers such as ethylene glycol dimethyl ether, ethylene glycol diethyl ether, propylene glycol-1-monomethyl ether acetate (PGMEA). Examples thereof include aliphatic esters such as ethyl acetate, n-butyl acetate, ethyl lactate, and n-butyl lactate.

  Of these, aromatic hydrocarbons such as dichlorobenzene, chlorobenzene, toluene, xylene, methicylene, cyclohexylbenzene, tetralin and the like are preferable because they have low water solubility and are not easily altered.

  These solvents may be used alone or in combination. In addition, the solvent which can be used is not limited to these.

  Since many materials that deteriorate significantly due to moisture such as cathodes are used for photoelectric conversion elements, the presence of moisture in the composition may cause moisture to remain in the film after drying, thereby reducing the characteristics of the element. It is not preferable because of the nature.

  In addition, in order to reduce a decrease in film formation stability due to solvent evaporation from the composition during wet film formation, the boiling point is 100 ° C. or more, preferably 150 ° C. as a solvent for the composition for photoelectric conversion elements. It is effective to use the above solvents.

  The ink composition for a photoelectric conversion element of the present invention is preferably used for a photoelectric conversion light-emitting element in which a photoelectric conversion material is a low-molecular material and a layer containing the photoelectric conversion material is formed by a wet film formation method. .

  The ink composition for photoelectric conversion elements of the present invention is mainly used to contain a photoelectric conversion material and form a photoelectric conversion layer, but may be used for other layers.

  The material of the present invention is particularly suitable for forming a thin film by a wet film forming method. In order to produce a thin film by wet film formation, it is necessary for the material to be dissolved in the above-described solvent or the like, but it is not sufficient to simply dissolve the material. Usually, even a material for forming a thin film by a dry film forming method can be dissolved to some extent in a solvent. However, in the wet film formation method, there is a process in which the material is dissolved in a solvent to form a thin film, and then the solvent evaporates to form a thin film. Many materials that are not suitable for the wet film formation method have high crystallinity. Therefore, it is difficult to form a good thin film due to crystallization in this process. The material of the present invention is also excellent in that crystallization hardly occurs.

  When producing the photoelectric conversion layer, the material of the present invention may be used alone or together with other materials. Furthermore, a charge transport layer may be formed between the organic semiconductor layer and the electrode in order to efficiently transport the generated carriers (holes or electrons) to the electrode or to reduce the barrier for carrier injection into the electrode. .

  As the electron-donating organic material that can be used in this case, polymers such as phenylene vinylene, fluorene, carbazole, indole, pyrene, pyrrole, picoline, thiophene, acetylene, diacetylene, and derivatives thereof are used. Moreover, it is not limited to a polymer, for example, porphyrin compounds such as porphine, tetraphenylporphine copper, phthalocyanine, copper phthalocyanine, titanium phthalocyanine oxide, and 1,1-bis {4- (di-P-tolylamino) phenyl } Cyclohexane, 4,4 ′, 4 ″ -trimethyltriphenylamine, N, N, N ′, N′-tetrakis (P-tolyl) -P-phenylenediamine, 1- (N, N-di-P— Tolylamino) naphthalene, 4,4′-bis (dimethylamino) -2-2′-dimethyltriphenylmethane, N, N, N ′, N′-tetraphenyl-4,4′-diaminobiphenyl, N, N ′ Aromatic compounds such as -diphenyl-N, N'-di-m-tolyl-4,4'-diaminobiphenyl, N-phenylcarbazole Stilbene compounds such as secondary amines, 4-di-P-tolylaminostilbene, 4- (di-P-tolylamino) -4 ′-[4- (di-P-tolylamino) styryl] stilbene, triazole derivatives, Oxazizazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives, pyrazolone derivatives, phenylenediamine derivatives, annealed amine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, Further, hydrazone derivatives, silazane derivatives, polysilane aniline copolymers, polymer oligomers, styrylamine compounds, aromatic dimethylidin compounds, poly (3-methylthiophene), and the like are also used.

  In the present invention, as long as the object of the present invention is not impaired, other known materials may be incorporated into the ink composition of the present invention in the photoelectric conversion layer as desired. A photoelectric conversion layer containing another known photoelectric conversion material may be stacked on the photoelectric conversion layer formed by a wet film formation method. In this case, the photoelectric conversion layer containing other known photoelectric conversion materials may be formed by a dry method such as a vacuum deposition method.

  In general, a photoelectric conversion element is manufactured over a light-transmitting substrate. Here, the light-transmitting substrate is a substrate that supports the photoelectric conversion element, and is preferably a smooth substrate having a light transmittance in the visible region of 400 to 700 nm of 50% or more.

  Specifically, a glass plate, a polymer plate, etc. are mentioned. Examples of the glass plate include soda lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone.

  In the ink composition for photoelectric conversion elements of the present invention, the content of the material for photoelectric conversion elements of the present invention is preferably 0.5 wt% or more. Usually, the thickness of the photoelectric conversion layer of the photoelectric conversion element is 10 to 100 nm, but in general, it is often 50 nm or more. When the film thickness is thinner than 50 nm, problems such as a decrease in photoelectric conversion performance occur. In order to easily form a film thickness of 50 nm or more, the solution concentration is preferably 0.5 wt% or more. When the concentration is lower than 0.5 wt%, it is difficult to form a thick film.

  A known additive may be added to the ink composition for a photoelectric conversion element of the present invention, if necessary, in addition to the above-described photoelectric conversion element material and solvent.

  As an additive, it is also possible to use a resin binder in the organic thin film layer. Examples of the resin binder for the organic thin film layer include insulating polymers such as polystyrene, polycarbonate, polyarylate, polyester, polyamide, polyimide, polyurethane, polysiloxane, polysulfone, polymethyl methacrylate, polymethyl acrylate, cellulose, polyethylene, polypropylene, and the like. And a conductive polymer such as polythiophene, polypyrrole, polyaniline, and polyparaphenylenevinylene. The resin binder may be used alone or in combination. Considering the mechanical strength of the thin film, a resin binder having a high glass transition temperature is preferable, and considering the charge mobility, a resin binder, a photoconductive polymer, or a conductive polymer having a structure not containing a polar group is preferable. Although it is preferable not to use this resin binder in terms of the characteristics of the organic semiconductor, it may be used depending on the purpose. The amount of the resin binder used in this case is not particularly limited, but is preferably 0.05 to 20% by mass in the organic semiconductor thin film layer.

  The ink composition for photoelectric conversion elements of the present invention is a known wet film forming method, for example, coating method, inkjet method, dip coating method, die coating method, spray coating method, spin coating method, roll coater method, dipping coating method. The film can be formed by screen printing, flexographic printing, screen printing, LB method, or the like.

  Here, the photoelectric conversion element that can be prepared using the photoelectric conversion element material of the present invention will be described in detail.

Generally, an organic photoelectric conversion element is composed of a pair of electrodes and an organic semiconductor layer. For the purpose of improving the photoelectric conversion efficiency, various types of element structures have been proposed depending on the energy matching between the electrode and the organic semiconductor and the method for producing the organic semiconductor layer.

1. A Schottky photoelectric conversion element is a photoelectric conversion element that uses a Schottky barrier formed at the interface between an electron-donating (p-type) or electron-accepting (n-type) organic semiconductor and an electrode to obtain photovoltaic power. . For example, when a p-type photoelectric conversion layer is used, a Schottky barrier is formed at the interface with the electrode having the smaller work function of the pair of electrodes, and charge separation occurs at the interface to perform photoelectric conversion. .

2. Bi-layer heterojunction photoelectric conversion element An electron-donating (p-type) and electron-accepting (n-type) organic semiconductor layer is individually formed between a pair of electrodes, and photocharge separation occurs at the pn junction interface. It is a photoelectric conversion element that obtains a photocurrent.

3. An organic semiconductor layer is formed by mixing an electron-donating (p-type) and electron-accepting (n-type) organic semiconductor material at an arbitrary ratio between a pair of electrodes of a bulk heterojunction photoelectric conversion element. At this time, the p-type and n-type materials may be uniformly dispersed or non-uniform. Since photocharge separation occurs at the interface formed by each p-type material and n-type material, a pn junction can be formed wider than the bilayer heterojunction type.

  The compound in the present invention can be applied to any device structure.

  At least one of the pair of electrodes constituting the photoelectric conversion element needs to transmit light. At this time, the light transmittance greatly affects the photoelectric conversion efficiency.

Specific examples include conductive metal oxides such as tin oxide, zinc oxide, indium oxide, and indium tin oxide (ITO), or gold, silver, platinum, chromium, nickel, lithium, indium, aluminum, calcium, and magnesium. In addition, a mixture or laminate of these metals and conductive metal oxides, inorganic conductive materials such as copper iodide and copper sulfide, organic conductive materials such as polyaniline, polythiophene and polypyrrole, silicon compounds and these And a laminate of ITO and the like.

  The shape of the electrode is generally a flat shape. In order to improve energy conversion efficiency, irregularities such as corrugations, pyramids, and combs may be intentionally formed. As a method for forming these electrodes, a general electrode forming method can be used. For example, a vacuum deposition method, a sputtering method, a PVD method such as an ion plating method, a CVD method, a chemical reaction method (such as a sol-gel method), Examples thereof include a casting method, a spray coating method, an ink jet method, and a spin coating method.

  The photoelectric conversion element may include other constituent members in addition to the above layers. For example, an optical film (filter) that does not transmit ultraviolet light may be provided. Ultraviolet rays contribute to the deterioration of organic materials due to their high energy. By blocking this ultraviolet light, the life of the device can be extended.

  A protective film may be provided for the purpose of protecting the photoelectric conversion layer against external impact. The protective film is, for example, a polymer film such as styrene resin, epoxy resin, acrylic resin, polyurethane, polyimide, polyvinyl alcohol, polyvinylidene fluoride, polyethylene polyvinyl alcohol copolymer, or inorganic oxide film such as silicon oxide, silicon nitride, or aluminum oxide. Or a metal plate such as a nitride film, aluminum, or a metal foil, or a laminated film thereof. In addition, only 1 type may be used for the material of these protective films, and 2 or more types may be sufficient as it.

  In general, it is said that organic devices are deteriorated by moisture and oxygen in the air. In order to prevent this, a barrier film may be provided. For example, a metal or an inorganic oxide is preferable, Ti, Al, Mg, Zr, silicon oxide, aluminum oxide, silicon oxynitride, aluminum oxynitride, magnesium oxide, zinc oxide, indium oxide, tin oxide, yttrium oxide, boron oxide, Calcium oxide etc. can be mentioned. The order of laminating these various functional films is not particularly limited, and functional films having these functions may be used.

  First, synthesis examples of the present invention will be described, but the present invention is not limited to these synthesis examples.

Synthesis example 1
Synthesis Method of Compound (1) Compound (1) was synthesized according to Reaction Formula 1 to Reaction Formula 2.

Reaction formula 1

Hereinafter, the synthesis method will be described with reference to Reaction Scheme 1. Under a nitrogen atmosphere, 21.5 g (0.54 mol) of sodium hydride (60%) and 50 g (0.54 mol) of 2-cyanofuran are added at room temperature in 300 ml of tert-pentyl alcohol with stirring. Thereafter, the temperature was raised to 100 ° C., and 36.2 g (0.18 mol) of diisopropyl succinate was added dropwise at this temperature. During the addition, the temperature of the reaction product was maintained at 100 ° C. After completion of the dropwise addition, stirring was performed for 3 hours at the same temperature while removing by-produced isopropyl alcohol out of the system. Thereafter, the mixture was cooled to 60 ° C., and at this temperature, a mixed solution of 43 g of acetic acid and 300 g of methanol was added dropwise. It was then filtered, washed with methanol and dried at 60 ° C. Further, the mixture was heated in methanol at 60 ° C. for 30 minutes, filtered while hot, and washed with methanol. 48g of dark red powder (III) was obtained by drying at 60 degreeC.

Reaction formula 2

Hereinafter, the synthesis method will be described with reference to Reaction Scheme 2.
Under a nitrogen atmosphere, 23 g of the compound represented by (III) obtained by the above method is suspended in 600 g of dimethylacetamide and heated to 50 ° C. with stirring. At this temperature, 25 g of sodium tert-butoxy are added and stirred at 50 ° C. for 30 minutes. Next, 83 g of 1-bromo-2-ethylhexane is added dropwise, and after completion of the addition, stirring is performed at 50 ° C. for 2 hours. When the reaction solution is cooled to room temperature and gradually poured into a mixed solution of 1000 g of water and 800 g of methanol, a dark red solid precipitates and becomes suspended. The mixture was stirred at room temperature for 1 hour, filtered, washed with water, washed with methanol and dried to obtain 24 g of a dark red powder.

Reaction formula 3

Hereinafter, the synthesis method will be described with reference to Reaction Scheme 3.
Under a nitrogen atmosphere, 13 g of the compound represented by (V) obtained by the above method is suspended in 500 g of chloroform, and cooled to 0 ° C. with stirring. At this temperature, 15 g of N-bromosuccinimide (NBS) is added, and the mixture is returned to room temperature and stirred for 12 hours. When the reaction solution is cooled to room temperature and gradually poured into a mixed solution of 1000 g of water and 800 g of methanol, a dark red-purple solid is precipitated and becomes a suspended state. The mixture was stirred at room temperature for 1 hour, filtered, washed with water, washed with methanol and dried to obtain 7 g of a dark red-purple powder.

Reaction formula 4

Hereinafter, the synthesis method will be described with reference to Reaction Scheme 4.
0.64 g (1 mmol) of the compound represented by (VI) 2 obtained by the above method under a nitrogen atmosphere, [4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2 -Il) phenyl] diphenylamine 0.20 g (0.5 mmol), tetrakis (triphenylphosphine) palladium 0.05 g, potassium carbonate (2M aqueous solution) 5 g, and xylene 30 g were added to a four-necked flask and heated to reflux for 5 hours. Thereafter, the reaction solution was poured into 400 ml of methanol, and the precipitated solid was collected by filtration and dried in a hot vacuum to obtain 0.32 g of (VII) as a crude product. The resulting crude product was purified by silica gel column chromatography.

Reaction formula 5

Hereinafter, the synthesis method will be described with reference to Reaction Scheme 5.
0.32 g (0.4 mmol) of the compound represented by (VII) 2 obtained by the above method under a nitrogen atmosphere, 2-acetyl-5- (4,4,5,5-tetramethyl-1,3, 2-Dioxaborolan-2-yl) thiophene 0.20 g (0.5 mmol), tetrakis (triphenylphosphine) palladium 0.05 g, potassium carbonate (2M aqueous solution) 5 g, and xylene 30 g are added to a four-necked flask and heated for 5 hours. Refluxed. Thereafter, the reaction solution was poured into 400 ml of methanol, and the precipitated solid was collected by filtration and dried in a hot vacuum to obtain 0.40 g of (VIII) as a crude product. The resulting crude product was purified by silica gel column chromatography.

Reaction formula 6

Hereinafter, the synthesis method will be described with reference to Reaction Scheme 6.
Under a nitrogen atmosphere, 0.40 g (0.45 mmol) of the compound (VIII) obtained by the above method, 0.8 g (10 mmol) of malononitrile, 2 g of pyridine, and 20 g of chloroform were added to a four-necked flask. Reacted for hours. Thereafter, the reaction solution was poured into 400 ml of methanol, and the precipitated solid was collected by filtration and dried in a hot vacuum to obtain 0.38 g of Compound (1) as a crude product. The resulting crude product was purified by silica gel column chromatography. Compound (1) was identified by mass spectrum (manufactured by Bruker Daltonics, Autoflex II), ¹ H-NMR, and ¹³ C-NMR (manufactured by JEOL, ECX-400P).

In addition, [4- (4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) phenyl] diphenylamine, 2-acetyl-5- (4) used for the synthesis of compound (1) , 4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl) thiophene used a commercially available reagent.
Synthesis Examples 2 to 44
The compounds in Table 1 were synthesized by combining the following reaction formulas (5) to (13).

Reaction formula 7

In Reaction Scheme 5, X represents —O— or —S—, and R ^{3 to} R ⁵ and R ^{6 to} R ⁸ each independently represent a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic carbonization. Hydrogen group, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aliphatic heterocyclic group, substituted or unsubstituted aromatic heterocyclic group, substituted silyl group, cyano group, substituted or unsubstituted alkoxyl group A substituted or unsubstituted aryloxy group or a substituted amino group.

Reaction formula 6

In Reaction Scheme 6, X represents —O— or —S—, and each R ¹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or aryloxy. Represents a carbonyl group,
R ^{3 to} R ⁵ and R ^{6 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted An aliphatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, and a substituted amino group.

Reaction formula 7

In Reaction Scheme 7, X represents —O— or —S—, and each R ¹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or aryloxy. Represents a carbonyl group,
R ^{3 to} R ⁵ and R ^{6 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted An aliphatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, and a substituted amino group.

Reaction formula 8

In Reaction Scheme 8, X represents —O— or —S—, and each R ¹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or aryloxy. Represents a carbonyl group,
R ^{3 to} R ⁵ and R ^{6 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted An aliphatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, and a substituted amino group; ³ is a substituent represented by the general formula [3].

Reaction formula 9

In Reaction Scheme 9, X represents —O— or —S—, and each R ¹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or aryloxy. Represents a carbonyl group,
R ^{3 to} R ⁵ and R ^{6 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted An aliphatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, and a substituted amino group; ³ is a substituent represented by the general formula [3]. R ⁶ is an aldehyde form of the substituent represented by the general formula [4].

Reaction formula 10

In Reaction Scheme 9, X represents —O— or —S—, and each R ¹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or aryloxy. Represents a carbonyl group,
R ^{3 to} R ⁵ and R ^{6 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted An aliphatic heterocyclic group, a substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, and a substituted amino group; ³ is a substituent represented by the general formula [3]. R ⁶ is a substituent represented by the general formula [4].

Reaction formula 11

In Reaction Formula 11, X represents —O— or —S—, and R ^{11 to} R ¹³ and R ^{14 to} R ¹⁶ each independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic carbonization. Hydrogen group, substituted or unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aliphatic heterocyclic group, substituted or unsubstituted aromatic heterocyclic group, substituted silyl group, cyano group, substituted or unsubstituted alkoxyl group A substituted or unsubstituted aryloxy group or a substituted amino group.

Reaction formula 12

In Reaction Scheme 12, each R ⁹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or an aryloxycarbonyl group,
X represents —O— or —S—, and each of R ^{11 to} R ¹³ and R ^{14 to} R ¹⁶ independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or Unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aliphatic heterocyclic group, substituted or unsubstituted aromatic heterocyclic group, substituted silyl group, cyano group, substituted or unsubstituted alkoxyl group, substituted or unsubstituted An aryloxy group and a substituted amino group.

Reaction formula 13

In Reaction Scheme 13, each R ⁹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or an aryloxycarbonyl group,
X represents —O— or —S—, and each of R ^{11 to} R ¹³ and R ^{14 to} R ¹⁶ independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or Unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aliphatic heterocyclic group, substituted or unsubstituted aromatic heterocyclic group, substituted silyl group, cyano group, substituted or unsubstituted alkoxyl group, substituted or unsubstituted An aryloxy group and a substituted amino group.

Reaction formula 14

In Reaction Scheme 14, each R ⁹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or an aryloxycarbonyl group,
X represents —O— or —S—, and each of R ^{11 to} R ¹³ and R ^{14 to} R ¹⁶ independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or Unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aliphatic heterocyclic group, substituted or unsubstituted aromatic heterocyclic group, substituted silyl group, cyano group, substituted or unsubstituted alkoxyl group, substituted or unsubstituted R ¹² is a substituent represented by the general formula [3].

Reaction formula 15

In Reaction Scheme 15, each R ⁹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or an aryloxycarbonyl group,
X represents —O— or —S—, and each of R ^{11 to} R ¹³ and R ^{14 to} R ¹⁶ independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or Unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aliphatic heterocyclic group, substituted or unsubstituted aromatic heterocyclic group, substituted silyl group, cyano group, substituted or unsubstituted alkoxyl group, substituted or unsubstituted R ¹² is a substituent represented by the general formula [3]. R ¹⁵ is an aldehyde form of the substituent represented by the general formula [4].

Reaction formula 16

In Reaction Scheme 16, each R ⁹ independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or an aryloxycarbonyl group,
X represents —O— or —S—, and each of R ^{11 to} R ¹³ and R ^{14 to} R ¹⁶ independently represents a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or Unsubstituted aromatic hydrocarbon group, substituted or unsubstituted aliphatic heterocyclic group, substituted or unsubstituted aromatic heterocyclic group, substituted silyl group, cyano group, substituted or unsubstituted alkoxyl group, substituted or unsubstituted R ¹² is a substituent represented by the general formula [3]. R ¹⁵ is a substituent represented by the general formula [4].

The structure of the compound of the present invention obtained by combining the above reaction formulas (5) to (16) was identified by mass spectrum, ¹ H-NMR and ¹³ C-NMR as in Synthesis Example 1. Table 4 shows the mass spectrum measurement results of the synthesized compounds. The compound numbers are the same as those described in Table 1 in this specification.

Hereinafter, although the following example demonstrates the photoelectric conversion element using the photoelectric conversion element material of this invention, this invention is not limited to the following example. In the examples, all mixing ratios are weight ratios unless otherwise specified. Vapor deposition (vacuum deposition) was performed in a vacuum of 10 ⁻⁶ Torr under conditions where temperature control such as heating and cooling of the substrate was not performed. The photoelectric conversion efficiency of the element was measured using a photoelectric conversion element having an area of 2 mm × 2 mm.

  Here, the photoelectric conversion efficiency is obtained by combining the solar simulator (# 8116) manufactured by ORIEL with an air mass filter and adjusting the light amount to 100 mW / cm 2 with a light meter to obtain a light source for measurement. The IV curve characteristics were measured and calculated using a KEITHLEYMODEL 2400 source meter while irradiating with light.

Example 1
A spin coating method of PEDOT: PSS (poly (3,4-ethylenedioxy) -2,5-thiophene / polystyrene sulfonic acid, BAYTRON P manufactured by Bayer) as a charge injection buffer layer on the cleaned glass plate with ITO electrode The film thickness was 60 nm. Subsequently, the compound (1) of Table (1) and the compound (n-3) of Table (2) were mixed at a ratio of 5: 4 and dissolved in chloroform at a concentration of 1.8 wt%. This was formed into a film with a thickness of 100 nm by a spin coat method to obtain a photoelectric conversion layer. Furthermore, 100 nm of Al was vapor-deposited thereon to form an electrode to obtain a photoelectric conversion element. The obtained device was transferred to a glove box having a moisture concentration and an oxygen concentration of 1 ppm or less without being exposed to the atmosphere, and sealed. The sealed element was taken out from the glove box and heat-treated on a plate at 100 ° C. for 20 minutes. The photoelectric conversion efficiency was measured about the element after heat processing. In addition, the photoelectric conversion efficiency after 100 hours of continuous driving in an 80 ° C. environment was measured. The results are shown in Table 5.

Examples 2-42
A device was prepared in the same manner as in Example 1 except that a photoelectric conversion layer was prepared using the compound (1) and the compound shown in Table (5) instead of the compound (n-3). The photoelectric conversion efficiency of this element was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 5.

Comparative Example 1
A device was prepared in the same manner as in Example 1 except that a photoelectric conversion layer was prepared using the compound (A) shown below. The photoelectric conversion efficiency of this element and the photoelectric conversion efficiency after 100 hours of continuous driving in an 80 ° C. environment were measured. The results are shown in Table 5.

  As is clear from Table 5, all the elements using the photoelectric conversion element material of the present invention had a longer lifetime and higher photoelectric conversion efficiency than the element prepared in Comparative Example 1.

Example 43
The cleaned glass plate with an ITO electrode was cleaned with oxygen plasma in a vacuum for 1 minute.
After the oxygen plasma cleaning, the compound (1) in Table 1 is deposited to form a film having a thickness of 20 nm, and then the compound (1) in Table 1 and the compound n-1 in Table 2 are mixed at a weight ratio of 1: 1. Co-evaporated to form a film with a thickness of 30 nm, and then a compound n-1 in Table 2 was vapor-deposited to form a film with a thickness of 30 nm, thereby forming a photoelectric conversion layer having a pin structure. Further, BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) was deposited to form a film having a thickness of 10 nm. On top of that, Al was deposited to a thickness of 100 nm to form an electrode to obtain a photoelectric conversion element. The obtained device was transferred to a glove box having a moisture concentration and an oxygen concentration of 1 ppm or less without being exposed to the atmosphere, and sealed. The sealed element was taken out from the glove box and the photoelectric conversion efficiency was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 6.

Examples 44-60
A device was produced in the same manner as in Example 43 except that a photoelectric conversion layer was produced using the compound (1) and the compound shown in Table 6 instead of the compound n-1. The photoelectric conversion efficiency of this element was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 6.

Comparative Example 2
A device was prepared in the same manner as in Example 43 except that a photoelectric conversion layer was prepared using the compound (A). The photoelectric conversion efficiency of this element and the photoelectric conversion efficiency after 100 hours of continuous driving in an 80 ° C. environment were measured. The results are shown in Table 6.

  As is clear from Table 6, all the elements using the photoelectric conversion element material of the present invention had a longer lifetime and higher photoelectric conversion efficiency than the element prepared in Comparative Example 2.

Example 61
Compound (3) in Table 1 was dissolved in chloroform at a concentration of 1.0 wt%. Further, a toluene dispersion solution of CdSe nanoparticles (Sigma-Aldrich, core type Lumidot ^™ CdSe520, solid content concentration: 5 mg / ml) was added to the chloroform solution of compound (3) to obtain a coating solution for a photoelectric conversion layer. It was. At this time, the weight ratio of the solid content of the chloroform solution of compound (3) and the solid content of the toluene dispersion solution of CdSe nanoparticles was added at a ratio of 1: 1.
A spin coating method of PEDOT: PSS (poly (3,4-ethylenedioxy) -2,5-thiophene / polystyrene sulfonic acid, BAYTRON P manufactured by Bayer) as a charge injection buffer layer on the cleaned glass plate with ITO electrode The film thickness was 60 nm. Subsequently, the coating solution for photoelectric conversion layers was formed into a film with a film thickness of 100 nm by the spin coat method, and the photoelectric conversion layer was obtained. Furthermore, 100 nm of Al was vapor-deposited thereon to form an electrode to obtain a photoelectric conversion element. The obtained device was transferred to a glove box having a moisture concentration and an oxygen concentration of 1 ppm or less without being exposed to the atmosphere, and sealed. The sealed element was taken out from the glove box and heat-treated on a plate at 100 ° C. for 20 minutes. The photoelectric conversion efficiency was measured about the element after heat processing. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 7.

Examples 62-68
A device was prepared in the same manner as in Example 61 except that a photoelectric conversion layer was prepared using the compounds shown in Table 7 instead of the compound (3). The photoelectric conversion efficiency of this element was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 7.

Comparative Example 3
A device was prepared in the same manner as in Example 61 except that a photoelectric conversion layer was prepared using the compound (A). The photoelectric conversion efficiency of this element and the photoelectric conversion efficiency after 100 hours of continuous driving in an 80 ° C. environment were measured. The results are shown in Table 7.

  As is clear from Table 7, all the elements using the photoelectric conversion element material of the present invention had a longer lifetime and higher photoelectric conversion efficiency than the element prepared in Comparative Example 3.

Example 69
Instead of the compound (3), the compound (7) was replaced with a toluene dispersion solution of CdSe nanoparticles instead of a toluene dispersion solution of CdSe nanoparticles (Sigma-Aldrich core type Lumidot ^™ CdSe520, solid content concentration: 5 mg / ml). A device was produced in the same manner as in Example 61 except that a photoelectric conversion layer was produced using Sigma-Aldrich core type Lumidot ^™ CdS480 (solid content concentration: 5 mg / ml). The photoelectric conversion efficiency of this element was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 8.

Examples 70-76
A device was prepared in the same manner as in Example 69 except that a photoelectric conversion layer was prepared using the compounds shown in Table 8 instead of the compound (7). The photoelectric conversion efficiency of this element was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 8.

Comparative Example 4
A device was produced in the same manner as in Example 69 except that a photoelectric conversion layer was produced using the compound (A). The photoelectric conversion efficiency of this element and the photoelectric conversion efficiency after 100 hours of continuous driving in an 80 ° C. environment were measured. The results are shown in Table 8.

  As is apparent from Table 8, all the elements using the photoelectric conversion element material of the present invention had a longer lifetime and higher photoelectric conversion efficiency than the element prepared in Comparative Example 4.

Example 77
Compound (8) in Table 1 was dissolved in chloroform at a concentration of 1.0 wt%. Further, a toluene solution of diethyl zinc (Sigma-Aldrich concentration: about 1M) is diluted with THF to obtain a solution of about 0.4M, and added to the chloroform solution of compound (8) to obtain a coating solution for the photoelectric conversion layer. Obtained. At this time, the weight ratio of the solid content of the chloroform solution of compound (8) and the solid content of the diethyl zinc solution was added at a ratio of 5: 7.
A spin coating method of PEDOT: PSS (poly (3,4-ethylenedioxy) -2,5-thiophene / polystyrene sulfonic acid, BAYTRON P manufactured by Bayer) as a charge injection buffer layer on the cleaned glass plate with ITO electrode The film thickness was 60 nm. Subsequently, the coating solution for photoelectric conversion layers was formed into a film with a film thickness of 100 nm by the spin coat method, and the photoelectric conversion layer was obtained. Furthermore, 100 nm of Al was vapor-deposited thereon to form an electrode to obtain a photoelectric conversion element. The obtained device was transferred to a glove box having a moisture concentration and an oxygen concentration of 1 ppm or less without being exposed to the atmosphere, and sealed. The sealed element was taken out from the glove box and heat-treated on a plate at 100 ° C. for 20 minutes. The photoelectric conversion efficiency was measured about the element after heat processing. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 9.

Examples 78-84
A device was prepared in the same manner as in Example 77 except that a photoelectric conversion layer was prepared using the compounds shown in Table 9 instead of the compound (8). The photoelectric conversion efficiency of this element was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 9.

Comparative Example 5
A device was prepared in the same manner as in Example 77 except that a photoelectric conversion layer was prepared using the compound (A). The photoelectric conversion efficiency of this element and the photoelectric conversion efficiency after 100 hours of continuous driving in an 80 ° C. environment were measured. The results are shown in Table 9.

  As is apparent from Table 9, all the elements using the photoelectric conversion element material of the present invention had a longer life and higher photoelectric conversion efficiency than the element prepared in Comparative Example 5.

Example 85
Titanium acetylacetonate (Ti (acac) ₃ ) is mixed with 27 g of 1-hexanol and 9 g of 2-acetylcyclohexanone, and titanium oxide P-25 manufactured by Nippon Aerosil Co., Ltd. (average particle size: 24 nm, average particle size is calculated by dynamic light scattering method) 36.6 g of Nanotrac particle size analyzer UPA-EX (manufactured by Nikkiso Co., Ltd.) used for the measurement principle is added, mixed with zirconia beads, and dispersed using a paint shaker to obtain a TiO ₂ dispersion solution. It was.
Compound (10) in Table 1 was dissolved in chloroform at a concentration of 1.0 wt%. Further, the TiO ₂ dispersion solution was added to the chloroform solution of the compound (10) to obtain a coating solution for a photoelectric conversion layer. At this time, the weight ratio of the solid content of the chloroform solution of compound (10) and the solid content of the TiO ₂ dispersion solution was added at a ratio of 1: 1.
A spin coating method of PEDOT: PSS (poly (3,4-ethylenedioxy) -2,5-thiophene / polystyrene sulfonic acid, BAYTRON P manufactured by Bayer) as a charge injection buffer layer on the cleaned glass plate with ITO electrode The film thickness was 60 nm. Subsequently, the coating solution for photoelectric conversion layers was formed into a film with a film thickness of 100 nm by the spin coat method, and the photoelectric conversion layer was obtained. Furthermore, 100 nm of Al was vapor-deposited thereon to form an electrode to obtain a photoelectric conversion element. The obtained device was transferred to a glove box having a moisture concentration and an oxygen concentration of 1 ppm or less without being exposed to the atmosphere, and sealed. The sealed element was taken out from the glove box and subjected to heat treatment on a hot plate at 100 ° C. for 20 minutes. The photoelectric conversion efficiency was measured about the element after heat processing. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 10.

Examples 86-92
A device was prepared in the same manner as in Example 85 except that a photoelectric conversion layer was prepared using the compound shown in Table 10 instead of the compound (10). The photoelectric conversion efficiency of this element was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 10.

Comparative Example 6
A device was prepared in the same manner as in Example 85 except that a photoelectric conversion layer was prepared using the compound (A). The photoelectric conversion efficiency of this element and the photoelectric conversion efficiency after 100 hours of continuous driving in an 80 ° C. environment were measured. The results are shown in Table 10.

  As is clear from Table 10, all the elements using the photoelectric conversion element material of the present invention had a longer life and higher photoelectric conversion efficiency than the element prepared in Comparative Example 6.

Example 93
Titanium acetylacetonate (Ti (acac) ₃ ) is mixed with 27 g of 1-hexanol and 9 g of 2-acetylcyclohexanone, and titanium oxide P-25 manufactured by Nippon Aerosil Co., Ltd. (average particle size: 24 nm, average particle size is calculated by dynamic light scattering method) 36.6 g of Nanotrac particle size analyzer UPA-EX (manufactured by Nikkiso Co., Ltd.) used for the measurement principle is added, mixed with zirconia beads, and dispersed using a paint shaker to obtain a TiO ₂ dispersion solution. It was.
On the cleaned glass plate with an ITO electrode, the above TiO ₂ dispersion solution was formed into a film having a thickness of 30 nm by a spin coating method. Next, the compound (6) in Table 1 and the compound n-3 in Table 2 were mixed at a ratio of 5: 4 and dissolved in chloroform at a concentration of 1.8 wt%. This was formed into a film with a thickness of 100 nm by a spin coat method to obtain a photoelectric conversion layer. Further, PEDOT: PSS (poly (3,4-ethylenedioxy) -2,5-thiophene / polystyrene sulfonic acid, BAYTRON P manufactured by Bayer) was formed into a film with a thickness of 60 nm by a spin coating method. Furthermore, 100 nm of Al was vapor-deposited thereon to form an electrode to obtain a photoelectric conversion element. The obtained device was transferred to a glove box having a moisture concentration and an oxygen concentration of 1 ppm or less without being exposed to the atmosphere, and sealed. The sealed element was taken out from the glove box and subjected to heat treatment on a hot plate at 100 ° C. for 20 minutes. The photoelectric conversion efficiency was measured about the element after heat processing. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 11.

Examples 94-100
A device was produced in the same manner as in Example 93 except that a photoelectric conversion layer was produced using the compounds shown in Table 11 instead of the compound (6). The photoelectric conversion efficiency of this element was measured. Further, photoelectric conversion after being continuously driven for 100 hours in an environment of 80 ° C. was measured. The results are shown in Table 11.

Comparative Example 7
A device was produced in the same manner as in Example 93 except that a photoelectric conversion layer was produced using the compound (A). The photoelectric conversion efficiency of this element and the photoelectric conversion efficiency after 100 hours of continuous driving in an 80 ° C. environment were measured. The results are shown in Table 11.

  As is clear from Table 11, all the elements using the photoelectric conversion element material of the present invention had a longer lifetime and higher photoelectric conversion efficiency than the element prepared in Comparative Example 7.

As mentioned above, the organic thin-film solar cell element which has high photoelectric conversion performance can be created by using the material for photoelectric conversion elements of this invention. It is clear that remarkably high performance is exhibited with respect to the comparative compound, and high conversion efficiency and long life of the photoelectric conversion element were achieved.

Claims (6)

An organic thin film solar cell element material comprising a compound represented by the following general formula [1] and / or a compound represented by the following general formula [2].
General formula [1]

(In the formula, X represents -O- or -S-,
R ¹ and R ² each independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or a substituted or unsubstituted aryloxycarbonyl group;
R ^{3 to} R ⁵ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or the following general formula [3] Represents a group. However, at least one of R ^{3 to} R ⁵ is a group represented by the following general formula [3].
R ^{6 to} R ⁸ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or the following general formula [4] Represents a group. However, at least one of R ^{6 to} R ⁸ is a group represented by the following general formula [4]. )
General formula [2]

(In the formula, X represents -O- or -S-,
R ⁹ and R ¹⁰ each independently represents a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted alkoxycarbonyl group, or a substituted or unsubstituted aryloxycarbonyl group;
R ^{11 to} R ¹³ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or the following general formula [3] Represents a group. However, at least one of R ^{11 to} R ¹³ is a group represented by the following general formula [3].
R ^{14 to} R ¹⁶ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, a substituted amino group, or the following general formula [4] Represents a group. However, at least one of R ^{14 to} R ¹⁶ is a group represented by the following general formula [4]. )
General formula [3]

(In the formula, Y represents a substituted or unsubstituted divalent aromatic hydrocarbon group, a substituted or unsubstituted divalent aromatic heterocyclic group, a combination thereof, or a direct bond.)
General formula [4]

(In the formula, Z represents a substituted or unsubstituted divalent aromatic hydrocarbon group, a substituted or unsubstituted divalent aromatic heterocyclic group, or a combination thereof, or a direct bond;
R ^{17 to} R ²⁶ are each independently a hydrogen atom, a halogen atom, a substituted or unsubstituted aliphatic hydrocarbon group, a substituted or unsubstituted aromatic hydrocarbon group, a substituted or unsubstituted aliphatic heterocyclic group, A substituted or unsubstituted aromatic heterocyclic group, a substituted silyl group, a cyano group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted aryloxy group, or a substituted amino group, R ^{17 to} R ²¹ , R ^{22 to} R ²⁶ , and R ²¹ and R ²² may form a ring with adjacent substituents. )  An organic thin film solar cell element in which an organic layer including a photoelectric conversion layer is formed between a pair of electrodes, wherein the photoelectric conversion layer comprises the organic thin film solar cell element material according to claim 1. .   The organic thin-film solar cell element according to claim 2, wherein the photoelectric conversion layer contains a fullerene derivative as an n-type semiconductor material.   The organic thin film solar cell element according to claim 2 or 3, wherein the photoelectric conversion layer contains an inorganic semiconductor as an n-type semiconductor material.   The organic thin-film solar cell element according to any one of claims 2 to 4, wherein the photoelectric conversion layer is formed by coating.   An ink composition for an organic thin-film solar cell element comprising the organic thin-film solar cell element material according to claim 1 and an organic solvent.