JP6536940B2 - Polymer compound, organic photoelectric conversion device, and method of manufacturing the device - Google Patents

Description

  The present invention relates to a novel polymer compound, an organic photoelectric conversion device having a photoelectric conversion layer containing the polymer compound, and a method of manufacturing the device.

  In recent years, development related to power generation by energy other than thermal power and nuclear power has attracted attention for reasons such as global warming suppression and substitution of nuclear power generation, and in particular, development related to improvement of conversion efficiency of photovoltaic power generation that is representative of clean energy. Is being promoted on a global scale.

Under these circumstances, organic thin film solar cells are lighter in weight, flexible, easier to manufacture at relatively low temperatures and can be made larger in area compared to silicon solar cells, and can be manufactured at low cost even in total. Has attracted attention as a next-generation solar cell. However, the power generation efficiency of solar cells using organic thin films remains at a low value compared to silicon solar cells, and not only for power generation applications such as home use, but also for portable information terminal applications outdoors (under sunlight) Also in the practical application as a battery source or a battery source for low power consumption devices for vehicles, improvement of power generation conversion efficiency is an important issue. In addition to this, in recent years, for example, a see-through type organic thin film solar cell that can be generated by being installed in a window and capable of generating electricity as well as daylighting that functions as a window has attracted much attention. Also, as shown in Patent Document 1, a see-through type organic thin film solar cell usually has a first transparent electrode, a bulk heterojunction photoelectric conversion layer, and a second transparent electrode laminated on a substrate. It has a structure. For this reason, as the appearance color of the organic thin film solar cell, basically, the transmission color of the photoelectric conversion layer (thin film) is dominantly reflected.
Furthermore, in Japanese Patent Application No. 2013-084162, a see-through type obtained from a mixture using a donor (organic p-type semiconductor) which is a polymer compound and a C [70] fullerene derivative as an acceptor (organic n-type semiconductor) A bulk heterojunction photoelectric conversion layer used for an organic thin film solar cell is disclosed.

JP, 2012-69803, A

  The bulk heterojunction type photoelectric conversion layer of Japanese Patent Application No. 2013-084162 has a high transmittance of about 70% and a small amount of coloring (not achromatic color but achromatic color). However, when the present inventors further studied, the heat resistance is not sufficient and the solubility in a solvent is high. For example, the baking temperature of the silver paste used for forming the cathode of the organic thin film solar cell is 120 In the heat processing at about -150 degreeC, the new problem that a photoelectric conversion efficiency falls further was discovered.

  In view of the above problems, the present invention is a polymer compound constituting a bulk heterojunction type photoelectric conversion layer, and is excellent in heat resistance and solvent resistance including the polymer compound, has high photoelectric conversion efficiency, and is achromatic. An object of the present invention is to provide a transparent organic photoelectric conversion device having a photoelectric conversion layer and a method of manufacturing the organic photoelectric conversion device.

The present inventors have found that the above problems can be solved by using a bulk hetero type photoelectric conversion layer containing a polymer compound and a C [70] fullerene derivative as described below, and completed the present invention .
That is, the present invention provides the following [1] to [20].
[1] A polymer compound represented by the following general formula (1) or (2).

(In Formula (1) or Formula (2), Y represents a divalent constitutional unit represented by any of the following Formula (3) to Formula (7), and R ₁ is each independently a hydrogen atom, A halogen atom, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group, or an alkoxy group having 1 to 12 carbon atoms is shown, R ₂ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group R ₃ is each independently represented by a hydrogen atom or the following formula (8), and at least one is represented by the following formula (8) R ′ is each independently an alkyl group having 1 to 16 carbon atoms An alkoxy group having 1 to 12 carbon atoms, an amino group, a monosubstituted amino group having an alkyl group having 1 to 16 carbon atoms as a substituent, a disubstituted amino group having an alkyl group having 1 to 16 carbon atoms as a substituent, a hydroxyl group And p is an integer of 1 to 5.
m and n indicate the number of repeating units, m is 2 to 100, and n is 1 to 50.
In the formula (4), R b represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group, and in the formula (7), R c represents a hydrogen atom, a halogen atom, 1 to 16 carbon atoms In the formula (3), k represents the number of repeating units, and is 1 to 5; )

[2] R ₁ in the general formula (1) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, and R ′ in the formula (8) is each independently having 1 to 1 carbon atoms A divalent substituted unit represented by Formula (3) or Formula (4) above, which is a mono-substituted amino group having an alkoxy group of 6, an amino group or an alkyl group having 1 to 6 carbon atoms as a substituent The high molecular compound as described in said [1] represented by General formula (1) which is it.
[3] R ₁ in the general formula (2) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, and R ′ in the formula (8) is each independently having 1 to 1 carbon atoms A divalent substituted unit represented by Formula (3) or Formula (6) above, which is a mono-substituted amino group having an alkoxy group of 6, an amino group, or an alkyl group having 1 to 6 carbon atoms as a substituent The high molecular compound as described in said [1] represented by General formula (2) which is it.
[4] R ₁ in the general formula (1) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, p in the formula (8) is 1 and R ′ is a methoxy group The polymer compound as described in said [1] or [2] represented by General formula (1) which is Y, and is a bivalent structural unit represented by following formula (9).

[5] R ₁ in the general formula (2) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, p in the formula (8) is 1 and R ′ is a methoxy group The polymer compound as described in said [1] or [3] represented by General formula (2) which is Y, and is a bivalent structural unit represented by said Formula (6).
[6] The m described in the general formula (1), wherein m: n in the general formula (1) is 97: 3 to 50:50, described in the above [1], [2] or [4] Polymer compound.
[7] The compound of the above-mentioned [1], [3] or [5], wherein m: n in the general formula (2) is 97: 3 to 50:50 and is represented by the general formula (2) Polymer compound.
[8] An organic photoelectric conversion device having a bulk hetero type photoelectric conversion layer, wherein the bulk hetero type photoelectric conversion layer is a polymer compound represented by the following general formula (1) or general formula (2) and C [70] fullerene An organic photoelectric conversion element containing a derivative.

(In Formula (1) or Formula (2), Y represents a divalent constitutional unit represented by any of the following Formula (3) to Formula (7), and R ₁ is each independently a hydrogen atom, A halogen atom, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group, or an alkoxy group having 1 to 12 carbon atoms is shown, R ₂ is a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group R ₃ is each independently represented by a hydrogen atom or the following formula (8), and at least one is represented by the following formula (8) R ′ is each independently an alkyl group having 1 to 16 carbon atoms An alkoxy group having 1 to 12 carbon atoms, an amino group, a monosubstituted amino group having an alkyl group having 1 to 16 carbon atoms as a substituent, a disubstituted amino group having an alkyl group having 1 to 16 carbon atoms as a substituent, a hydroxyl group And p is an integer of 1 to 5.
m and n indicate the number of repeating units, m is 2 to 100, and n is 1 to 50.
In the formula (4), R b represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group, and in the formula (7), R c represents a hydrogen atom, a halogen atom, 1 to 16 carbon atoms In the formula (3), k represents the number of repeating units, and is 1 to 5; )

[9] R ₁ in the general formula (1) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, and R ′ in the formula (8) is each independently having 1 to 1 carbon atoms A divalent substituted unit represented by Formula (3) or Formula (4) above, which is a mono-substituted amino group having an alkoxy group of 6, an amino group or an alkyl group having 1 to 6 carbon atoms as a substituent The organic photoelectric conversion device according to the above [8], which is
[10] R ₁ in the general formula (2) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, and R ′ in the formula (8) is each independently having 1 to 1 carbon atoms A divalent substituted unit represented by Formula (3) or Formula (6) above, which is a mono-substituted amino group having an alkoxy group of 6, an amino group, or an alkyl group having 1 to 6 carbon atoms as a substituent The organic photoelectric conversion device according to the above [8], which is
[11] R ₁ in the general formula (1) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, p in the formula (8) is 1 and R ′ is a methoxy group The organic photoelectric conversion element as described in said [8] or [9] whose Y is a bivalent structural unit represented by following formula (9).

[12] R ₁ in the general formula (2) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, p in the formula (8) is 1 and R ′ is a methoxy group The organic photoelectric conversion element as described in said [8] or [10] whose Y is a bivalent structural unit represented by said Formula (6).
[13] The mass ratio of the polymer compound represented by the general formula (1) or the general formula (2) and the C [70] fullerene derivative constituting the bulk hetero type photoelectric conversion layer is 1: 2 to 1: 2: The organic photoelectric conversion element according to any one of the above [8] to [12], which is 5.
[14] The organic photoelectric conversion device according to any one of the above [8] to [13], wherein the C [70] fullerene derivative is PC [70] BM.
[15] The bulk hetero type photoelectric conversion layer contains at least one of an aliphatic thiol represented by the following general formula (I) and an iodine compound represented by the following general formula (II): ] The organic photoelectric conversion element of any one of Claims.

(Wherein, R _M represents an alkylene group having 3 to 15 carbon atoms, and R _N represents an alkylene group having 3 to 15 carbon atoms.)
[16] The organic photoelectric conversion device according to the above [15], wherein the aliphatic thiol is octanedithiol and the iodine compound is diiodooctane.
[17] The organic photoelectric conversion device according to any one of the above [8] to [16], wherein the transmittance of the visible region of the bulk hetero type photoelectric conversion layer is 50 nm or more at a thickness of 100 nm. .
[18] The bulk hetero type photoelectric conversion layer has a thickness of 100 nm, and a C light source and a 2 ° visual field in the CIE (International Commission on Illumination) L ^* a ^* b ^* color system specified in JIS Z 8729-1994. The organic photoelectric conversion element according to any one of the above [8] to [17], wherein the saturation C ^* value measured under the conditions is 10 or less.
[19] An organic thin film solar cell including the organic photoelectric conversion device according to any one of the above [8] to [18].
[20] A method for producing an organic photoelectric conversion device according to any one of the above [8] to [18], which comprises forming an electrode to be an anode on a transparent substrate,
Forming a bulk hetero type photoelectric conversion layer containing the polymer compound represented by the general formula (1) or the general formula (2) and the C [70] fullerene derivative,
Forming an electrode to be a cathode;
The manufacturing method of an organic photoelectric conversion element containing.

  According to the present invention, a polymer compound constituting the bulk heterojunction type photoelectric conversion layer, and the polymer compound, which is excellent in heat resistance and solvent resistance, has high photoelectric conversion efficiency, and is achromatic and transparent An organic photoelectric conversion element having a photoelectric conversion layer and a method of manufacturing the organic photoelectric conversion element can be provided.

It is sectional drawing which shows an example of the organic photoelectric conversion element of this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a top view or perspective view which shows an example of the cathode of the organic photoelectric conversion element of this invention, (a) is a top view of a stripe electrode and a mesh electrode, (b) is the permeation | transmission which laminated the transparent conductive layer on the metal layer. Is a perspective view of a solid electrode.

[Polymer compound]
The polymer compound of the present invention is represented by the following general formula (1) or (2).

In Formula (1) or Formula (2), m shows the number of repeating units and is 2-100. If m is less than 2, the π electron conjugated system is not sufficiently extended, so that sufficient solar light absorption efficiency can not be obtained, which is not preferable. Moreover, when m exceeds 100, the solubility in a solvent is lowered, and film formation by a wet method becomes difficult, which is not preferable. Therefore, m is preferably 5 to 90, more preferably 10 to 50.
Similarly, in Formula (1) or Formula (2), n shows the number of repeating units and is 1-50. If n is less than 1, crosslinking reaction does not occur. If n is more than 50, the solubility is significantly reduced. Therefore, n is preferably 1 to 40, more preferably 1 to 30.
In addition, said m and n are values calculated based on the weight average molecular weight of a polymer, and the said weight average molecular weight is the value measured by the method as described in an Example.
In the present invention, the copolymer represented by the general formula (1) or the general formula (2) may be a random copolymer or a block copolymer. From the viewpoint of simplicity of synthesis, random copolymers are preferred.

  In the formula (1) or the formula (2), the ratio of the number of repeating units for m and n, that is, m: n is preferably 97: 3 to 50:50, more preferably 95: 5 to 60:40, More preferably, it is 95: 5 to 70:30. When m: n is in this range, heat resistance and solvent resistance are improved after thermal crosslinking.

In Formula (1) or Formula (2), R ₁ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group, or an alkoxy group having 1 to 12 carbon atoms.
Examples of the alkyl group having 1 to 16 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, pentyl group (isomer Hexyl group (including isomer), heptyl group (including isomer), octyl group (including isomer), nonyl group (including isomer), decyl group (including isomer), undecyl Groups (including isomers), dodecyl groups (including isomers), and the like.
As the substituted alkyl group having 1 to 16 carbon atoms, a hydrogen atom of the above alkyl group is a halogen atom such as fluorine atom, chlorine atom, bromine atom or iodine atom, an oxygen atom, a silicon atom, a sulfur atom or a phosphorus atom And alkyl groups substituted by
As a C1-C12 alkoxy group, it is the same as that of said alkyl group.
Among these, from the viewpoint of improving the solubility in a solvent, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group is preferable, and an alkyl group is more preferable. Moreover, it is preferable that R ₁ is the same. Furthermore, among the alkyl groups, alkyl groups having 6 to 15 carbon atoms are preferable, and 2-ethylhexyl group is more preferable.

In Formula (1) or Formula (2), R ₃ is each independently represented by a hydrogen atom or the following Formula (8), and at least one is represented by the following Formula (8). R ′ independently represents an alkyl group having 1 to 16 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an amino group, a monosubstituted amino group having an alkyl group having 1 to 16 carbon atoms as a substituent, It is a disubstituted amino group having an alkyl group of 16 as a substituent, and a hydroxyl group. That is, one monomer, which is a constituent unit of the copolymer represented by the general formula (1) or (2) of the present invention, is selected from 4,4-bis (5-hexenyl) -4H-cyclopenta [2, 1- b: By forming a chemical structure in which at least one substituent having an electron donating group is introduced onto the benzene ring at the carbon atom constituting the double bond at the side chain terminal of 3,4-b '] dithiophene After thermal crosslinking, heat resistance and solvent resistance can be imparted.
In the formula (8) of the present invention, the bond derived from the carbon atom on the benzene ring is directly bonded to the carbon atom of the double bond.

As a C1-C16 alkyl group, it is the same as that of the alkyl group mentioned above. As a C1-C12 alkoxy group, it is the same as that of said alkyl group. As a mono-substituted or di-substituted amino group which has a C1-C16 alkyl group as a substituent, the monoalkyl substituted or dialkyl substituted amino group which has a substituent chosen from the alkyl group mentioned above is mentioned.
Among them, an alkoxy group having 1 to 6 carbon atoms, an amino group, and a disubstituted amino group having an alkyl group having 1 to 6 carbon atoms as a substituent are preferable, a methoxy group and an amino group are more preferable, and more preferable And methoxy.

P is an integer of 1 to 5 and is preferably 1 or 2 from the viewpoint of heat resistance improvement.

In the formula (8), a 4-methoxyphenylene group, a 3-methoxyphenylene group or a 2-methoxyphenylene group in which p is 1 and R ′ is a methoxy group is preferable, and a 4-methoxyphenylene group is more preferable.
As R ₃ , it is preferable that all be a formula (8), and it is more preferable that p is 1 and it is a 4-methoxy phenylene group.

In formula (2), _{R 2} represents a hydrogen atom, a halogen atom, an alkyl group or a substituted alkyl group having 1 to 16 carbon atoms. The alkyl group having 1 to 16 carbon atoms or the substituted alkyl group is the same as R ₁ described above. Among these, from the viewpoint of improving the solubility in a solvent, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group is preferable, and an alkyl group is more preferable. Moreover, a C6-C15 alkyl group is preferable among the alkyl groups, and n-hexyl group is more preferable.

  In Formula (1) or Formula (2), Y shows the bivalent structural unit represented by either of following formula (3)-(7).

K in Formula (3) shows the number of repeating units, and is 1-5. Preferably, it is 1 to 3, and more preferably 2. Rb in Formula (4) represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms, or a substituted alkyl group. The alkyl group having 1 to 16 carbon atoms or the substituted alkyl group is the same as R ₁ described above. Among these, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group is preferable, and from the viewpoint of improving the solubility in a solvent, an alkyl group having 6 to 15 carbon atoms is preferable, and an alkyl group having 6 to 10 carbon atoms Is more preferred.
Rc in Formula (7) represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms, or a substituted alkyl group. The alkyl group having 1 to 16 carbon atoms or the substituted alkyl group is the same as R ₁ described above. Among these, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group is preferable, and from the viewpoint of improving the solubility in a solvent, an alkyl group having 6 to 15 carbon atoms is more preferable, and an alkyl having 6 to 10 carbon atoms Groups are more preferred.

  In the formula (1), Y is preferably a divalent constitutional unit represented by the above formula (3) or (4), and more preferably, Y is represented by the following formula (9) Unit of value.

  In the formula (2), Y is preferably a divalent constitutional unit represented by the formula (3) or (6), more preferably, Y is represented by the formula (6) Unit of value.

[Method of synthesizing polymer compound]
The polymer compound of the present invention can be synthesized by a known method, and is not particularly limited, but the polymer compound represented by the general formula (1) can be synthesized, for example, according to the following synthesis scheme . That is, it can synthesize | combine by the method of polymerizing each monomer which comprises a high molecular compound by coupling reaction in presence of a metal catalyst.

  Steps 1 and 2 are steps of halogenating the starting material in the general formula (1) to synthesize an intermediate. As a reagent used in that case, N-bromo succinimide etc. are mentioned, for example.

  Step 3 is a monomer having the above intermediate and a divalent constitutional unit Y represented by any of the above formulas (3) to (7), or 4,4-bis (5-hexenyl) -4H-cyclopenta [2 , 1-b; 3,4-b '] dithiophene is polymerized by a coupling reaction in the presence of a metal complex catalyst, and a substituent having an electron donating group on the benzene ring (Formula (8)) And introduce the polymer compound of the present invention. It does not specifically limit as reaction used in that case, For example, Suzuki coupling reaction, Stille coupling reaction, Kumada coupling etc. can be used.

The metal complex is not particularly limited, and examples thereof include reduction catalysts such as copper complexes, nickel complexes and palladium complexes. Among these, nickel complexes and palladium complexes are preferable.
Examples of the nickel complex include bis (1,5-cyclooctadiene) nickel, tetrakis (triphenylphosphine) nickel, dichloro (2,2′-bipyridine) nickel and the like, and among these, the viewpoint of polymerization performance Therefore, bis (1,5-cyclooctadiene) nickel is preferable.
Examples of palladium complexes include tetrakis (triphenylphosphine) palladium, dichloro {1,3-bis (diphenylphosphine) propane} palladium, tris (dibenzylidene) dipalladium and the like. Among these, tris (dibenzylidene) dipalladium is preferable from the viewpoint of polymerization performance.
In addition, you may use these metal complexes individually or in combination of 2 or more types.

Step 3 is usually carried out in air or under an inert atmosphere, preferably under an inert atmosphere. The inert atmosphere includes a nitrogen gas or argon gas atmosphere.
The polymerization reaction is not particularly limited, but is preferably carried out under heating and reflux. The heating temperature is usually room temperature to 180 ° C, preferably 80 to 150 ° C, and more preferably 80 to 120 ° C. The pressure at the time of the polymerization reaction is not particularly limited, but it is usually carried out under normal pressure.
The polymerization time varies depending on the types of monomers and catalysts used, temperature and pressure at the time of polymerization, etc., but is usually 1 to 240 hours, preferably 20 to 120 hours.

  The polymer compound represented by the general formula (2) is, for example, a monomer constituting the polymer compound in the presence of a metal catalyst in the same manner as the method for synthesizing the polymer compound represented by the general formula (1). It can be synthesized by a method of polymerization by a coupling reaction.

That is, the starting material is halogenated to synthesize an intermediate, and a monomer having a bivalent structural unit Y represented by the intermediate and any of the above formulas (3) to (7) or 4,4-bis (5) -Hexenyl) -4H-cyclopenta [2,1-b; 3,4-b '] dithiophene is polymerized by a coupling reaction in the presence of a metal catalyst, and further has an electron donating group on the benzene ring By introducing a substituent (formula (8)) and synthesizing the polymer compound of the present invention, the polymer compound represented by the general formula (2) can be synthesized. It does not specifically limit as reaction used in that case, For example, Suzuki coupling reaction, stille coupling reaction, direct arylation reaction etc. can be used.
The ratio of the number of repeating units applied to m and n can be controlled by appropriately adjusting the mixing ratio of the monomers at the start of the reaction.

[Organic photoelectric conversion element]
The organic photoelectric conversion device of the present invention is an organic photoelectric conversion device having a bulk hetero type photoelectric conversion layer, wherein the bulk hetero type photoelectric conversion layer is a polymer compound represented by the following general formula (1) or (2) And a C [70] fullerene derivative.

In Formula (1) or Formula (2), m shows the number of repeating units and is 2-100. If m is less than 2, the π electron conjugated system is not sufficiently extended, so that sufficient solar light absorption efficiency can not be obtained, which is not preferable. Moreover, when m exceeds 100, the solubility in a solvent is lowered, and film formation by a wet method becomes difficult, which is not preferable. Therefore, m is preferably 5 to 90, more preferably 10 to 50.
Similarly, in Formula (1) or Formula (2), n shows the number of repeating units and is 1-50. If n is less than 1, crosslinking reaction does not occur. If n is more than 50, the solubility is significantly reduced. Therefore, n is preferably 1 to 40, more preferably 1 to 30.
In addition, said m and n are values calculated based on the weight average molecular weight of a polymer, and the said weight average molecular weight is the value measured by the method as described in an Example.

  In the formula (1) or the formula (2), the ratio of the number of repeating units for m and n, that is, m: n is preferably 97: 3 to 50:50, more preferably 95: 5 to 60:40, More preferably, it is 95: 5 to 70:30. When m: n is in this range, the heat resistance and the solvent resistance are improved after thermal crosslinking, so when producing a photoelectric conversion device using the compound of the present invention, higher temperatures can be obtained in a later step. The annealing process and the like become possible, and a coating process by a wet method which requires improvement of device characteristics or heat treatment can be introduced, leading to cost reduction and improvement of productivity.

In Formula (1) or Formula (2), each R ₁ independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms, or a substituted alkyl group having 1 to 16 carbon atoms, or 1 to 12 carbon atoms An alkoxy group is shown.
Examples of the alkyl group having 1 to 16 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, s-butyl group, t-butyl group, pentyl group (isomer Hexyl group (including isomer), heptyl group (including isomer), octyl group (including isomer), nonyl group (including isomer), decyl group (including isomer), undecyl Groups (including isomers), dodecyl groups (including isomers), and the like.
As the substituted alkyl group having 1 to 16 carbon atoms, a hydrogen atom of the above alkyl group is a halogen atom such as fluorine atom, chlorine atom, bromine atom or iodine atom, an oxygen atom, a silicon atom, a sulfur atom or a phosphorus atom And alkyl groups substituted by
As a C1-C12 alkoxy group, it is the same as that of said alkyl group.
Among these, from the viewpoint of improving the solubility in a solvent, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group is preferable, and an alkyl group is more preferable. Moreover, it is preferable that R ₁ is the same. Furthermore, among the alkyl groups, alkyl groups having 6 to 15 carbon atoms are preferable, and 2-ethylhexyl group is more preferable.

In Formula (1) or Formula (2), R ₃ is each independently represented by a hydrogen atom or the following Formula (8), and at least one is represented by the following Formula (8). R ′ independently represents an alkyl group having 1 to 16 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an amino group, a monosubstituted amino group having an alkyl group having 1 to 16 carbon atoms as a substituent, It is a disubstituted amino group having an alkyl group of 16 as a substituent, and a hydroxyl group. That is, one monomer, which is a constituent unit of the copolymer represented by the general formula (1) or (2) of the present invention, is selected from 4,4-bis (5-hexenyl) -4H-cyclopenta [2, 1- b: By forming a chemical structure in which at least one substituent having an electron donating group is introduced onto the benzene ring at the carbon atom constituting the double bond at the side chain terminal of 3,4-b '] dithiophene By heat crosslinking, heat resistance and solvent resistance after film formation can be imparted.

As a C1-C16 alkyl group, it is the same as that of the alkyl group mentioned above. As a C1-C12 alkoxy group, it is the same as that of said alkoxy group. As a mono-substituted or di-substituted amino group which has a C1-C16 alkyl group as a substituent, the monoalkyl substituted or dialkyl substituted amino group which has a substituent chosen from the alkyl group mentioned above is mentioned.
Among them, an alkoxy group having 1 to 6 carbon atoms, an amino group, and a disubstituted amino group having an alkyl group having 1 to 6 carbon atoms as a substituent are preferable, a methoxy group and an amino group are more preferable, and more preferable And methoxy.

P is an integer of 1 to 5, and preferably 1 or 2 from the viewpoint of heat resistance improvement.

In the formula (8), a 4-methoxyphenylene group, a 3-methoxyphenylene group or a 2-methoxyphenylene group in which p is 1 and R ′ is a methoxy group is preferable, and a 4-methoxyphenylene group is more preferable.
As R ₃ , it is preferable that all be a formula (8), and it is more preferable that p is 1 and it is a 4-methoxy phenylene group.

In formula (2), _{R 2} represents a hydrogen atom, a halogen atom, an alkyl group or a substituted alkyl group having 1 to 16 carbon atoms. The alkyl group having 1 to 16 carbon atoms or the substituted alkyl group is the same as R ₁ described above. Among these, from the viewpoint of improving the solubility in a solvent, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group is preferable, and an alkyl group is more preferable. Moreover, a C6-C15 alkyl group is preferable among the alkyl groups, and n-hexyl group is more preferable.

  In Formula (1) or Formula (2), Y shows the bivalent structural unit represented by either of following formula (3)-(7).

K in Formula (3) shows the number of repeating units, and is 1-5. Preferably, it is 1 to 3, and more preferably 2. Rb in Formula (4) represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms, or a substituted alkyl group. The alkyl group having 1 to 16 carbon atoms or the substituted alkyl group is the same as R ₁ described above. Among these, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group is preferable, and from the viewpoint of improving the solubility in a solvent, an alkyl group having 6 to 15 carbon atoms is preferable, and an alkyl group having 6 to 10 carbon atoms Is more preferred.
Rc in Formula (7) represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms, or a substituted alkyl group. The alkyl group having 1 to 16 carbon atoms or the substituted alkyl group is the same as R ₁ described above. Among these, an alkyl group having 1 to 16 carbon atoms or a substituted alkyl group is preferable, and from the viewpoint of improving the solubility in a solvent, an alkyl group having 6 to 15 carbon atoms is more preferable, and an alkyl having 6 to 10 carbon atoms Groups are more preferred.

  In the formula (1), Y is preferably a divalent constitutional unit represented by the above formula (3) or (4), and more preferably, Y is represented by the following formula (8) Unit of value.

  In the formula (2), Y is preferably a divalent constitutional unit represented by the formula (3) or (6), more preferably, Y is represented by the formula (6) Unit of value.

  An example of sectional drawing of the organic photoelectric conversion element of this invention is shown in FIG. In FIG. 1, an organic photoelectric conversion element 1 is an organic photoelectric conversion element having a bulk hetero type photoelectric conversion layer 3 between a pair of anodes 2 and a cathode 4 stacked on a transparent substrate (not shown).

  An organic photoelectric conversion element is an element that generates an electromotive force by light energy irradiation, and in general, an element that converts light energy into electrical energy is provided with an electrode for extracting charges in the photoelectric conversion layer. It is As an organic photoelectric conversion element, various organic semiconductor devices, such as an organic thin film solar cell and a photodiode, are mentioned. Among these, the present invention is suitable for organic thin film solar cells.

  In the organic photoelectric conversion device of the present invention, the bulk hetero type photoelectric conversion layer contains the polymer compound represented by the above general formula (1) or the general formula (2) and a C [70] fullerene derivative.

In the present invention, C [70] fullerene derivative refers to a concept including a compound in which at least part of which is modified for C ₇₀ fullerene and C ₇₀ fullerene carbon atoms is 70. Examples of C [70] fullerene derivatives include phenyl C71 butyric acid methyl ester (PC [70] BM) indene C70 monoadduct (IC [70] MA) and indene C70 bisadduct (IC [70] BA). Among these, phenyl C71 butyric acid methyl ester (PC [70] BM) is more preferable in that the obtained bulk hetero type light conversion layer tends to be achromatic.
The bulk hetero type photoelectric conversion layer may be, for example, C60, C76, C78, C78, C82, C84, C90, C94 as an n-type semiconductor material other than the C [70] fullerene derivative as long as the effects of the present invention are not impaired. And unsubstituted fullerene compounds, and derivatives thereof, 1,4,5,8-naphthalenetetracarboxylic dianhydride (NTCDA), 3,4,9,10-perylenetetracarboxylic dianhydride (PTCDA) 3,4,9,10-perylenetetracarboxylic bisbenzimidazole (PTCBI), N, N'-dioctyl-3,4,9,10-naphthyltetracarboxydiimide (PTCDI-C8H), 2- (4-) Biphenylyl) -5- (4-t-butylphenyl) -1,3,4-o Oxazole derivatives such as xadiazole (PBD), 2,5-di (1-naphthyl) -1,3,4-oxadiazole (BND), 3- (4-biphenylyl) -4-phenyl-5- (4-) Triazole derivatives such as t-butylphenyl) -1,2,4-triazole (TAZ), phenanthroline derivatives, phosphine oxide derivatives, carbon nanotubes (CNT), derivatives in which a cyano group is introduced into a poly-p-phenylene vinylene polymer (CN-PPV), etc. may be included.

  In the present invention, the bulk hetero type photoelectric conversion layer preferably contains at least one of an aliphatic thiol represented by the following general formula (I) and an iodine compound represented by the following general formula (II).

(Wherein, R _M represents an alkylene group having 3 to 15 carbon atoms, and R _N represents an alkylene group having 3 to 15 carbon atoms.)
By including the aliphatic thiol and the iodine compound, the solubility of the polymer compound (1) is improved, and layer separation of the polymer compound and the C [70] fullerene derivative is promoted, and the conversion efficiency is improved.
The mass ratio of the aliphatic thiol represented by the above general formula (I) and the iodine compound represented by the above general formula (II) to the polymer compound is 10: 1 to 1: 1, preferably 5: 1 to 1: 1.

  An octane dithiol, a butane dithiol etc. are mentioned as said aliphatic thiol. Of these, octane dithiol is preferred. Further, examples of the iodine compound include diiodooctane and diiodobutane. Among these, diiodooctane is preferable.

In the present invention, the mass ratio of the polymer compound represented by the general formula (1) or the general formula (2) to the C [70] fullerene derivative is 1: 1 to 1:10, preferably 1: 2 to 1: 5. If the mass ratio is in this range, it is preferable because an achromatic and transparent bulk hetero type photoelectric conversion layer can be obtained.
In the above, the polymer compound represented by the general formula (1) or the general formula (2) has an absorption spectrum peak in the near infrared region, while the C [70] fullerene derivative has an absorption spectrum around 500 nm. Although it has a peak, it is thought that the absorption spectrum of the visible light region of the mixture becomes flat and does not have a clear peak by mixing the two.

  The transmittance of the bulk hetero type photoelectric conversion layer in the visible light region (about 550 nm) is preferably 50% or more, more preferably 60% or more, and still more preferably 70% or more, at a thickness of 100 nm. When the transmittance is in the above range, the transparency of the photoelectric conversion layer is high, and when it is installed as a solar cell on a window glass of a car, a building or a general house, sunlight can be sufficiently collected and high visibility is obtained. Because it is

The bulk hetero-type photoelectric conversion layer has a thickness of 100 nm, and is measured with a C light source and 2 ° visual field conditions in the CIE (International Lighting Commission) L ^* a ^* b ^* color system specified in JIS Z 8729-1994. The saturation C ^* value to be calculated is preferably 10 or less, more preferably 4 or less. If the saturation C ^* value is 10 or less, it is preferable because the amount of coloring is small and it approaches an achromatic color.

  30-300 nm is preferable, and, as for the thickness of the bulk hetero type photoelectric conversion layer of this invention, 50-150 nm is more preferable. If the thickness is in this range, it is preferable because the photoelectric conversion layer has high transparency and is achromatic.

The anode 2 is preferably a transparent electrode, and for example, tin-doped indium oxide (ITO), IrO ₂ , In ₂ O ₃ , SnO ₂ , indium oxide-zinc oxide (IZO), ZnO (Ga, Al doped), MoO ₃ and transparent semiconductor electrodes formed of materials such as NiO. The thickness of the electrode is preferably 10 to 200 nm, more preferably 20 to 150 nm.

  Examples of the cathode 4 include Ag, Al, Pt, Ir, Cr, ZnO, CNT, Ca, LiF, and alloys, composites thereof, and the like.

  The transmittance of the transparent substrate in the visible light range (about 550 nm) is preferably 80% or more, more preferably 85% or more, and still more preferably 90% or more. Examples of the transparent substrate include glass and plastic substrates. The thickness of the transparent substrate is usually about 0.1 to 10 mm and is selected from the viewpoints of mechanical strength, thermal expansion coefficient, weight, and cost, but is not particularly limited.

  Moreover, the organic photoelectric conversion element of the present invention is a hole transport layer such as poly (3,4) -ethylenedioxythiophene / polystyrene sulfonate (PEDOT-PSS) between the anode 2 and the bulk hetero type photoelectric conversion layer. Preferably, a hole blocking layer such as vasocuproin is provided between the bulk hetero type photoelectric conversion layer and the cathode 4.

[Organic thin film solar cells]
The organic photoelectric conversion element of the present invention can be used as an organic thin film solar cell. The organic thin film solar cell including the organic photoelectric conversion device of the present invention is excellent in heat resistance and high in photoelectric conversion efficiency, and the bulk hetero type photoelectric conversion layer is highly transparent and has an achromatic appearance, and see-through Can be used as an organic thin film solar cell.

[Method of manufacturing organic photoelectric conversion device]
The method for producing an organic photoelectric conversion element of the present invention comprises the steps of: forming an electrode to be an anode on a transparent substrate;
Forming a bulk hetero type photoelectric conversion layer containing the polymer compound represented by the general formula (1) or the general formula (2) and the C [70] fullerene derivative, and forming an electrode to be a cathode It is a manufacturing method of an organic photoelectric conversion element containing.

(1-1) Anode Forming Step The anode forming step in the present invention is a step of forming an electrode to be an anode on a transparent substrate.
As a method of forming an electrode to be an anode, a general method of forming an electrode can be used. For example, a dry method such as a sputtering method, a vacuum evaporation method, or an ion plating method, or a wet method such as a dip coating method of a solution containing ITO fine particles or a spin coating method can be used in forming ITO.

(1-2) Photoelectric Conversion Layer Forming Step The photoelectric conversion layer forming step is a bulk hetero type photoelectric conversion layer containing the polymer compound represented by the general formula (1) or the general formula (2) and a C [70] fullerene derivative. Is a process of forming Specifically, a polymer compound and a C [70] fullerene derivative are dissolved in a solvent and mixed and dispersed on the anode formed in the anode forming step, and the solvent is dried, and bulk hetero type photoelectric conversion is performed. Form a layer. The solvent is not particularly limited, and as described above, chlorobenzene, ortho-dichlorobenzene, chloroform, dichloromethane, toluene, tetrahydrofuran and the like can be used. The method for forming the bulk hetero type photoelectric conversion layer is not particularly limited, but a general wet film forming method can be used. For example, formation methods such as dip coating method, spin coating method, gravure coating method, roll coating method and the like can be mentioned.

(1-3) Cathode formation process A cathode formation process is a process of forming an electrode which becomes a cathode on the bulk hetero-type photoelectric conversion layer formed in the above (1-2). The cathode material is as described above, but as described later, it can be used by patterning (stripe electrode, mesh electrode etc.), laminating a plurality of cathode materials, or mixing them. .
As a method of forming an electrode to be a cathode, the polymer compound represented by the general formula (1) or the general formula (2) of the present invention is excellent in heat resistance and low in solubility in a solvent. A wet method such as an inkjet method can be used. That is, for example, the cathode can be formed by pattern printing silver paste or the like by screen printing, and heat treatment at 120 to 150 ° C.
On the other hand, dry methods such as known sputtering methods, vacuum evaporation methods, ion plating methods and the like can also be used.

  For the purpose of improving the transmittance as the organic photoelectric conversion device of the present invention, the cathode formation pattern is appropriately adjusted in aperture ratio within the range not to impair the photoelectric conversion efficiency of the organic photoelectric conversion device, and a stripe electrode made of metal thin film It may be a mesh electrode. For example, as shown to Fig.2 (a), the stripe electrode 11 and the mesh electrode 12 which consist of thin films, such as silver, are mentioned. In addition, for the same purpose, the cathode may be a solid electrode in which a transparent conductive layer or the like is laminated on a metal thin film. For example, as shown in FIG. 2 (b), an extremely thin film of silver is formed as the metal layer 15 on the power generation layer 14 (a structure in which only the cathode portion is removed from the organic photoelectric conversion device of the present invention). The structure (transparent solid electrode 13) which laminated ITO as 16 is mentioned. However, in this case, when the thickness of the metal is increased, the transmittance as the organic photoelectric conversion element is decreased, and therefore, the thickness needs to be appropriately adjusted and used.

(1-4) Hole transport layer formation process In the manufacturing method of the photoelectric conversion element of this invention, you may provide the process of forming a hole transport layer between an anode and a bulk hetero type photoelectric conversion layer.
As a method of forming the hole transport layer, a general thin film forming method can be used. For example, a film is formed by a vacuum evaporation method, a sputtering method, an ion plating method, or the like. In addition, the film may be formed by a wet method such as dip coating method, spin coating method, roll coating method and the like.

(1-5) Hole blocking layer formation process In the manufacturing method of the photoelectric conversion element of this invention, you may provide the process of forming a hole blocking layer further between a photoelectric converting layer and a cathode.
As a method of forming the front hole blocking layer, a general thin film forming method can be used. For example, a film is formed by a vacuum evaporation method, a sputtering method, an ion plating method, or the like.
An organic photoelectric conversion element can be manufactured by implementing the process shown above.

  EXAMPLES The present invention will next be described in more detail by way of examples, which should not be construed as limiting the invention thereto.

The measuring method which concerns on the high molecular compound performed in the Example is shown below.
(A) Measurement of weight average molecular weight of polymer GPC apparatus [manufactured by Tosoh Corp., apparatus name "HLC-8228GPC", column: product name "SHODEX GPC KF-804L + GPC KF-805L", column temperature: 40 ° C, detector: UV detector (254 nm), eluent: THF, column flow rate: 1.0 ml / min, polystyrene conversion], the weight average molecular weight (Mw) in terms of standard polystyrene of the obtained polymer and the polydispersity of the polymer The degree (Mw / Mn) was measured. In addition, the number n of repeating units was calculated from this weight average molecular weight.
(B) ¹ H-NMR Measurement An FT-NMR apparatus (manufactured by JEOL, apparatus name “JNM-A500”) was used.

The transmittance of the visible light region of the photoelectric conversion layer produced in the example and the comparative example, the saturation C ^*, and the photoelectric conversion efficiency of the photoelectric conversion element were evaluated by the following methods.
The mixed solution for forming the bulk hetero type photoelectric conversion layer used in Examples 3 and 4 and Comparative Examples 1 and 2 was applied to a synthetic quartz substrate by a spin coating method so that the bulk hetero type photoelectric conversion layer had a thickness of 100 nm. The formed photoelectric conversion layer was heated at 150 ° C. for 30 minutes in a nitrogen atmosphere to prepare a sample for measurement of transmittance and chroma C ^* . The light transmittance evaluation and the evaluation of saturation were performed by the following method using the obtained sample.
(C) Light transmittance evaluation The UV-Vis-NIR light transmission spectrum of the bulk hetero type photoelectric conversion layer formed on the synthetic quartz substrate was measured with a spectrophotometer (manufactured by Shimadzu Corporation, model number: UV-3600).
(D) Evaluation of saturation L ^* value, a ^* value, b ^* value of L ^* a ^* b ^* color system of photoelectric conversion layer using a spectrophotometer (manufactured by Shimadzu Corporation, model number: UV-3600) Was measured. Further, using the obtained a ^* value and b ^* value, the saturation C ^* was calculated according to formula (1). The smaller the saturation C ^* , the smaller the coloration (closer to achromatic color).

The measurement was performed under a 2 ° visual field condition using a C light source in the CIE (International Lighting Commission) L ^* a ^* b ^* color system specified in JIS Z 8729-1994.
The above is generally classified according to the L ^* a ^* b ^* color space of CIE (International Commission on Illumination). The three components of this system are L ^* (describe brightness on scales 0-100), a ^* (red / magenta-green axis; positive values are red / magenta, negative values are green) And b ^* (yellow-blue axis; positive values are yellow and negative values are blue).

(E) Photoelectric conversion efficiency evaluation A solar simulator (manufactured by Wacom Denso Corp., model number: WXS-50S-1.5) and a voltage-current generator (manufactured by ADC, R6243) while being irradiated with light of a uniform 100 W tungsten lamp. Short-circuit current density (J _SC ) and open circuit voltage (Voc) were measured. Moreover, the photoelectric conversion efficiency (PCE) was computed by processing the obtained data with solar cell characteristic measurement software (made by System House Sunrise, name: W32-R6244SOL-C).

Synthesis Example 1: Synthesis of Oligomer (1a)
4,80-bis (2-ethylhexyl) -4H-cyclopenta [2,1-b; 3,4-b '] dithiophene 2.80 g (6.97 mmol), 4,7-dibromo-2,1,3- 0.340 g (1.16 mmol) of benzothiadiazole, 2.40 g (0.017 mol) of potassium carbonate, 0.081 g (0.363 mmol) of Pd (OAc) ₂ and 0.212 g (2.08 mmol) of pivalic acid in 500 mL of In a Schlenk tube, it was dissolved using 100 mL of DMF. The resulting solution was purged with nitrogen for 5 minutes, and the reaction mixture was stirred at 80 ° C. for 2 hours and then dried directly under vacuum to evaporate DMF from the organic layer. The reaction residue is purified by silica gel chromatography using hexane as a developing solvent, concentrated under vacuum, then dissolved in 10 mL of chloroform, and subjected to SEC (size exclusion chromatography) (flow rate 14 mL / min), The molecular weight distribution was measured. By the above operation, a compound (1a) represented by the following formula was obtained (yield 45%) as 0.485 g of a dark purple solid.
¹ H-NMR (500 MHz, CDCl ₃ ): δ 8.08, 8.06, 8.05 (s, 2 H, 3-CPDT, peak ratio (racemic 2-ethylhexyl group) 1: 2: 1), 83 (s, 2H, BT), 7.21, 7.20 (d, 2H, J = 5.0 Hz, 6-CPDT), 6.99 (m, 2H, 5-CPDT), 1.98 ( m, 8 H, CH ₂ ), 1. 27 (m, 4 H, CH), 1.03-0.84 (m, 32 H, CH ₂ ), 0.76 (t, J = 10.0 Hz, 12 H, 12 H, CH ₃ ).
¹³ C NMR (125 MHz, CDCl ₃ ): δ 158.6, 158.3, 152.6, 139.1, 138.7, 137.0, 126.1 (CH), 125.3 (CH), 124.2 (CH), 122.6 (CH), 53.7 (4-CPDT), 43.3 (CH ₂ ), 35.2 (CH), 34.2, 28.7, 27.4, 22.8 (CH ₂ ), 14.1, 10.7 (CH ₃ ).
FABMS: m / z = 937 [M] +.

Synthesis Example 2: Synthesis of Oligomer (1b)
Oligomer (1a), 0.410 g (0.438 mmol) is dissolved in 4.0 mL of THF, and further dissolved in 0.172 g (0.966 mmol) of N-bromosuccinimide, 5.0 mL of THF, THF of Oligomer 1 at 0 ° C. Dropped into solution. The resulting solution was stirred for 1 hour. The THF was distilled off under vacuum, the product was dissolved in hexane and purified by silica gel chromatography using hexane as developing solvent. Furthermore, the molecular weight distribution was measured by SEC using chloroform as a developing solvent. By the above operation, a compound (1b) represented by the following formula was obtained as a 0.347 g dark purple oil (yield: 72%).
¹ H-NMR (500 MHz, CDCl ₃ ): δ 8.03, 8.01, 7.99 (s, 2 H, 3-CPDT, peak ratio (racemic 2-ethylhexyl group) 1: 2: 1), 79 (s, 2H, BT), 6.98, 6.97, 6.96 (s, 2H, 5-CPDT, peak ratio (racemic 2-ethylhexyl group) 1: 2: 1), 1.99-1 _{.83 (m, 8H, CH 2} ), 1.24 (m, 4H, CH), 1.03-0.59 (m, 32H, CH 2, CH 3).
¹³ C NMR (125 MHz, CDCl ₃ ): δ 157.8, 157.0, 152.5, 139.5, 138.1, 137.3, 126.0, 125.4 (CH), 124.2 (CH), 122.5 (CH), 54.6 (4-CPDT), 43.1 (CH ₂ ), 35.2 (CH), 34.1, 28.5, 27.4, 22.8 (CH ₂ ), 14.0, 10.7 (CH ₃ ).
FABMS: m / z = 1095 [M] +.

Synthesis Example 3: Synthesis of Oligomer (2a)
4, 4-Bis (2-ethylhexyl) -4H-cyclopenta [2,1-b; 3,4-b '] dithiophene 1.63 g (4.06 mmol), 1,3-dibromo-5-hexyl-5H- 0.200 g (0.508 mmol) of thienopyrrole-4,6-dione, 0.352 g (1.27 mmol) of potassium carbonate, 56 mg (0.25 mmol) of Pd (OAc) ₂ and 76 mg (75 mmol) of bivalic acid, 250 mL of Schlenk In a tube, 45 mL of DMF was dissolved and the resulting solution was purged with nitrogen for 5 minutes. The reaction mixture was stirred at 80 ° C. for 2 hours and then dried directly under vacuum to evaporate DMF from the organic layer. The reaction residue is purified by silica gel chromatography using hexane and dichloromethane as a developing solvent, which is concentrated under vacuum and then dissolved in 10 mL of chloroform, followed by SEC (size exclusion chromatography) (flow rate 14 mL / min) , Molecular weight distribution was measured. By the above operation, a compound (2a) represented by the following formula was obtained as an orange-yellow oil (228 mg) (yield 43%).
¹ H-NMR (500 MHz, CDCl ₃ ): δ 7.95, 7.91, 7.88 (s, 2H, 3-CPDT (cyclopenta [2,1-b; 3,4-b '] dithiophene), peak Ratio (racemic 2-ethylhexyl group) 1: 2: 1), 7.25 (d, J = 5.0 Hz, 2H, 6-CPDT), 6.97 (m, 2H, 5-CPDT), 3. 69 (t, 2H, J = 10.0 Hz, α-proton of TPD (5H-thienopyrrole-4,6-dione)), 2.17-0.61 (m, 49H, CH, CH ₂ , CH ₃ ) .
FABMS: m / z = 1038 [M] +.

Synthesis Example 4: Synthesis of Oligomer (2b)
Oligomer (2a), 0.428 g (0.412 mmol) is dissolved in 10 mL of THF, and 0.161 g (0.906 mmol) of N-bromosuccinimide is dissolved in 10 mL of THF, and THF solution of oligomer (2a) is dissolved at 0 ° C. Dripped into the The resulting solution was stirred for 1 hour. Next, THF was distilled off under vacuum, the product was dissolved in dichloromethane, and purified by silica gel chromatography using hexane and dichloromethane as a developing solvent. Furthermore, the molecular weight distribution was measured by SEC using chloroform as a developing solvent. By the above-described operation, a compound (2b) represented by the following formula was obtained as a pale yellow oil (0.416 g) (yield: 84%).
¹ H-NMR (500 MHz, CDCl ₃ ): δ 7.89, 7.86, 7.82 (s, 2 H, 3-CPDT, peak ratio (racemic 2-ethylhexyl group) 1: 2: 1), 98, 6.97, 6.96 (s, 2H, 5-CPDT, peak ratio (racemic 2-ethylhexyl group) 1: 2: 1), 3.66 (t, 2H, J = 7.5 Hz, TPD Α protons), 1.94-0.58 (m, 49H, CH, CH ₂ , CH ₃ ).
¹³ C NMR (125 MHz, CDCl ₃ ): δ 162.7, 158.3, 157.8, 140.5, 136.4, 132.2, 127.3, 125.4 (5-CPDT), 124 .4 (3-CPDT), 113.1 , 54.7 (4- _{cyclopentadithiophene), 43.0, 38.6 (CH 2} ), 35.2 (CH), 34.1, 31.4 , 28.6, 28.4, 27.4, 26.6 , 22.8, 22.5 (CH 2), 14.1, 14.0, and 10.7 (CH 3).
FABMS: m / z = 1196 [M] +.

Example 1 Synthesis of Polymer Compound (1-1)
Oligomer (1b), 108 mg (0.099 mmol) and 2,2'-bithiophene-5,5'-diboronic acid bis (pinacol) ester, 45.3 mg (0.108 mmol), 2,6-dibromo-4,4 -Bis (5-hexenyl) -4H-cyclopenta [2,1-b; 3,4-b '] dithiophene, 2.5 mg (0.005 mmol) in a 10 mL Schlenk tube, 1.4 mL of anhydrous p-xylene Dissolved in The solution was purged with argon gas for 30 minutes, and 4.5 mg (5 mol%) of tris (dibenzylideneacetone) palladium (0) and tri (o-tolyl) phosphine (3.0 mg, 10 mol%) were added. The reaction mixture is stirred at 95 ° C. for 5.5 hours, benzeneboronic acid 2,2-dimethyltrimethylene ester (2 mg, 0.01 mmol), 4-bromoanisole (1.0 mL) is added, and stirring is continued for another 5 hours did. It was poured into 150 mL of methanol containing 8 mL of 37% hydrochloric acid. The precipitate was washed for 1 day with soxhlet extraction with ethanol and methyl ethyl ketone for 1 day each and extracted into chloroform. The chloroform solution of the polymer was filtered through a column of silica gel and precipitated in methanol. The precipitate was collected by filtration and vacuum dried to obtain a polymer compound (1-1) represented by the following formula as a 55 mg dark blue powder (yield 55%).
¹ H-NMR (500 MHz, CDCl ₃ ): δ 8.05 (br, 2H, 3-CPDT), 7.81 (br, 2H, phenyl), 7.07 (br, 6H, 5-CPDT & bithiophene) _{, 1.97 (br, 8H, CH} 2), 1.10-0.60 (m, 30H, CH, CH 2, CH 3). GPC (THF, polystyrene standard solution): Mn = 10,500, Mw / Mn = 1.49.

Example 2 Synthesis of Polymer Compound (2-1)
Oligomer (2b), 103 mg (0.086 mmol), and 2,1,3-benzothiadiazole-4,7-bis (boronic acid pinacol ester) 36.7 mg (0.095 mmol), 2,6-dibromo-4,2 4-bis (5-hexenyl) -4H-cyclopenta [2,1-b; 3,4-b '] dithiophene 2.5 mg (potassium carbonate aqueous solution 0.36 mL (2 M) and Aliquat 336) One drop was dissolved in 1.2 mL of xylene in a 25 mL Schlenk tube. The solution was purged with argon gas for 30 minutes, and tris (dibenzylideneacetone) palladium (0), 3.9 mg (5 mol%) and tri (o-tolyl) phosphine, 2.6 mg (10 mol%) were added. The reaction was stirred at 95 ° C. for 5.5 hours, benzeneboronic acid 2,2-dimethyltrimethylene ester (0.1 equivalent), 4-bromoanisole (1.0 mL) were added and stirred for another 5 hours. Thereafter, the resulting mixture was poured into 150 mL of methanol containing 8 mL of 37% hydrochloric acid.
The precipitate was washed by soxhlet extraction with ethanol and methyl ethyl ketone for 1 day each, and extracted into chloroform. The chloroform solution of the polymer was filtered through a column of silica gel and precipitated in methanol. The precipitate was collected by filtration and vacuum dried to obtain a polymer compound (2-1) represented by the following formula as a 86 mg dark blue powder (yield 86%).
¹ H NMR (500 MHz, CDCl ₃ ): δ 8.11 (br, 2H, thienyl), 7.97 (br, 2H, thienyl), 7.87 (br, 2H, phenyl), 3.70 (br , 2H, CH ₂ ), 2.02-0.50 (br, 79 H, CH, CH ₂ , CH ₃ ). GPC (THF, polystyrene standard solution): Mn = 17,000, Mw / Mn = 1.92.

[Example 3]
2.3 mg of a polymer compound (1-1) as a p-type semiconductor, 6.6 mg of PC [70] BM (trade name "Nanom Spectra E110" manufactured by Frontier Carbon Inc.) as an n-type semiconductor material, and 1,8 -6.6 mg of octanedithiol (made by Tokyo Chemical Industry Co., Ltd.) was weighed, 0.66 mL of dehydrated chlorobenzene (made by Sigma Aldrich, dehydrated product) was added under nitrogen atmosphere, and it stirred under nitrogen atmosphere for 24 hours. Then, the mixture was filtered with a syringe filter with a pore size of 0.45 μm to prepare a mixed solution for forming a photoelectric conversion layer (the mass ratio of the polymer compound (1-1): PC [70] BM is 1: 2.9). .
Next, a glass substrate with an ITO film cleaned by cleaning and UV-ozone treatment (a glass substrate with a transparent conductive film having a tin-doped indium oxide film formed on the glass substrate, surface resistivity: 14 (Ω / □)) 20 nm of PEDOT-PSS (manufactured by Clevios) as a hole transport layer by the method described in the literature (Brabec, C. J. et al., Advanced Materials, 2009, 21st, 1st page) Then, the photoelectric conversion layer was formed to have a thickness of 100 nm by spin coating using the above mixed solution on the obtained hole transport layer. The surface of the obtained photoelectric conversion layer was a homogeneous, non-cloudy film. The obtained photoelectric conversion layer was heated to 150 ° C. for 30 minutes under a nitrogen atmosphere.
Furthermore, on this photoelectric conversion layer, calcium (manufactured by Kanto Chemical Co., Ltd.) is 10 nm, aluminum (manufactured by High Purity Chemical Laboratory Co., Ltd.) is 100 nm (vacuum degree: 8.2 × 10 ⁻⁵ Pa, film forming speed: 0.15 nm) / S), it laminated | stacked in this order, and produced the organic photoelectric conversion element 1. FIG.
The aforementioned (e) photoelectric conversion efficiency was evaluated using the obtained organic photoelectric conversion element 1, and the photoelectric conversion efficiency (PCE) was calculated. The results are shown in Table 1.

  In addition, (c) the light transmittance is evaluated, the UV-Vis-NIR light transmission spectrum is measured, and the visible light (550 nm) transmittance of the photoelectric conversion layer is determined from the spectrum, and (d) saturation The evaluation of The results are shown in Table 1.

Example 4
An organic photoelectric conversion element 2 was produced in the same manner as in Example 3 except that a polymer compound (2-1) was used instead of the polymer compound (1-1) as a p-type semiconductor. The aforementioned (e) photoelectric conversion efficiency was evaluated using the obtained organic photoelectric conversion element 2, and the photoelectric conversion efficiency (PCE) was calculated. The results are shown in Table 1.

  In addition, (c) the light transmittance is evaluated, the UV-Vis-NIR light transmission spectrum is measured, and the visible light (550 nm) transmittance of the photoelectric conversion layer is determined from the spectrum, and (d) saturation The evaluation of The results are shown in Table 1.

Comparative Example 1
An organic photoelectric conversion element 3 was produced in the same manner as in Example 3 except that the polymer compound (11) was used as a p-type semiconductor. The aforementioned (e) photoelectric conversion efficiency was evaluated using the obtained organic photoelectric conversion element 3, and the photoelectric conversion efficiency (PCE) was calculated. The results are shown in Table 1.

  Further, (c) light transmittance was evaluated, the transmittance of visible light (550 nm) of the photoelectric conversion layer was measured, and (d) evaluation of saturation was performed. The results are shown in Table 1.

Comparative Example 2
An organic photoelectric conversion element 4 was produced in the same manner as in Example 4 except that the polymer compound (12) was used as a p-type semiconductor. The aforementioned (e) photoelectric conversion efficiency was evaluated using the obtained organic photoelectric conversion element 4, and the photoelectric conversion efficiency (PCE) was calculated. The results are shown in Table 1.

  Further, (c) light transmittance was evaluated, the transmittance of visible light (550 nm) of the photoelectric conversion layer was measured, and (d) evaluation of saturation was performed. The results are shown in Table 1.

[Example 5]
A photoelectric conversion layer was produced in the same manner as in Example 3. Subsequently, silver (manufactured by High Purity Chemical Laboratory Co., Ltd.) of 10 nm (vacuum degree: 1.0 × 10 ⁻⁴ Pa or less, film forming rate: 0.3 nm / s) is laminated, and then ITO is grown to 100 nm with an RF sputtering apparatus. It laminated | stacked and produced the organic photoelectric conversion element 5. The aforementioned (e) photoelectric conversion efficiency was evaluated using the obtained organic photoelectric conversion element 5, and the photoelectric conversion efficiency (PCE) was calculated. Furthermore, the transmittance | permeability of the visible light (550 nm) of the organic photoelectric conversion element 5 was measured with the spectrophotometer used by (c) light transmittance evaluation mentioned above. The results are shown in Table 2.

[Example 6]
A photoelectric conversion layer was produced in the same manner as in Example 3. Subsequently, a silver paste (manufactured by MHI STAR BELT, EC264) is printed on the photoelectric conversion layer in a mesh (grid shape, line width 50 μm, pitch 0.5 mm) pattern of 90% aperture ratio (thickness: 30 μm, 120 ° C.) It heated for 10 minutes, and produced the organic photoelectric conversion element 6. (e) Photoelectric conversion efficiency evaluation was performed using the obtained organic photoelectric conversion element 6, photoelectric conversion efficiency (PCE) was calculated, and it was mentioned above. (C) The transmittance of visible light (550 nm) of the organic photoelectric conversion element 6 was measured by the spectrophotometer used in the light transmittance evaluation, and the results are shown in Table 2.

[Example 7]
The photoelectric conversion layer was produced by the method similar to Example 5 except having used a compound (2-1) as p-type material. Subsequently, silver (manufactured by High Purity Chemical Laboratory Co., Ltd.) of 10 nm (vacuum degree: 1.0 × 10 ⁻⁴ Pa or less, film forming speed: 0.3 nm / s) is laminated, and then ITO is formed 100 nm by an RF sputtering apparatus It laminated | stacked and produced the organic photoelectric conversion element 7. FIG. (E) The photoelectric conversion efficiency is evaluated using the obtained organic photoelectric conversion element 7, the photoelectric conversion efficiency (PCE) is calculated, and the spectrophotometer used in the light transmittance evaluation described above (c) is further calculated. The transmittance of visible light (550 nm) of the organic photoelectric conversion element 7 was measured. The results are shown in Table 2.

[Example 8]
The photoelectric conversion layer was produced by the method similar to Example 6 except having used a compound (2-1) as p-type material. Subsequently, a silver paste (manufactured by Three Star Belt, EC 264) is printed on the photoelectric conversion layer in a mesh (grid shape, line width 50 μm, pitch 0.5 mm) pattern with an aperture ratio of 90% (thickness: 30 μm) The organic photoelectric conversion element 8 was produced by heating at 120 ° C. for 10 minutes. (E) The photoelectric conversion efficiency is evaluated using the obtained organic photoelectric conversion element 8 to calculate the photoelectric conversion efficiency (PCE), and further, using the spectrophotometer used in the light transmittance evaluation described above (c) The transmittance of visible light (550 nm) of the organic photoelectric conversion element 8 was measured. The results are shown in Table 2.

  The organic photoelectric conversion elements of the present invention used in Examples 3 and 4 were found to be excellent in heat resistance because the photoelectric conversion efficiency is higher than in Comparative Examples 1 and 2. Further, as is clear from Examples 5 to 8, since heat treatment at least at 150 ° C. is possible, the production of an electrode to be a cathode can be handled by a wet method such as simple screen printing using silver paste or the like. It was found that cost reduction and productivity improvement could be achieved. Furthermore, it turned out that the organic photoelectric conversion element of this invention has high transparency, even if it uses silver paste as a cathode material.

  Since the organic photoelectric conversion element of the present invention is superior in heat resistance to conventional products, it is installed in a window of a car, a building or a general house, and can generate electricity as well as daylighting which is a function as a window. It is possible to use as a see-through type organic thin film solar cell which can also reduce the cooling cost.

1: organic photoelectric conversion element 2: anode 3: bulk hetero type photoelectric conversion layer 4: cathode 11: stripe electrode 12: mesh electrode 13: transparent solid electrode 14: power generation layer 15: metal layer 16: transparent conductive layer

Claims (20)

The high molecular compound represented by following General formula (1) or General formula (2).


(In formula (1), Y represents a divalent structure units represented by the following formula (3) or formula (4), _{R 1} is each independently an alkyl group or a substituted alkyl having a carbon number of 1 to 16 represents a group, _{R 2} represents an alkyl group having a carbon number of 1 to 16, _{R 3} are each independently represented by a hydrogen atom or the following formula (8), at least one represented by the following formula (8) .R 'is an alkoxy group having a carbon number. 1 to 6, p is an integer of 1 to 5.
Moreover, in Formula (2), Y shows the bivalent structural unit represented by either of following formula (3), Formula (4), or Formula (6), R < ₁ > is carbon number independently, respectively. R ₁ represents an alkyl group of 1 to 16 or a substituted alkyl group, R ₂ represents an alkyl group having 1 to 16 carbon atoms, R ₃ is each independently a hydrogen atom or represented by the following formula (8), and at least one is It is represented by the following formula (8). R 'is a C1-C6 alkoxy group, p is an integer of 1-5.
m and n indicate the number of repeating units, m is 2 to 100, and n is 1 to 50.
In formula (4), R b represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms, or a substituted alkyl group, and in formula (3), k represents the number of repeating units and is 1 to 5. )

R ₁ in the general formula (1) are each independently an alkyl group or a substituted alkyl group having 1 to 16 carbon atoms, the formula (8) in the R 'is alkoxy group having a carbon number of 1 to 6 The polymer compound according to claim 1, represented by the general formula (1), wherein Y is a divalent constitutional unit represented by the formula (3) or the formula (4). R ₁ in the general formula (2) are each independently an alkyl group or a substituted alkyl group having 1 to 16 carbon atoms, the formula (8) in the R 'is alkoxy group having a carbon number of 1 to 6 The polymer compound according to claim 1, represented by the general formula (2), wherein Y is a divalent constitutional unit represented by the formula (3) or the formula (6). R ₁ in the general formula (1) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, p in the formula (8) is 1 and R ′ is a methoxy group, The polymer compound according to claim 1 or 2, which is represented by General Formula (1), wherein Y is a divalent constitutional unit represented by the following Formula (9).
R ₁ in the general formula (2) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, p in the formula (8) is 1 and R ′ is a methoxy group, The polymer compound according to claim 1 or 3, which is represented by General Formula (2), wherein Y is a divalent constitutional unit represented by Formula (6).   The polymer compound according to claim 1, 2 or 4, which is represented by the general formula (1), wherein m: n in the general formula (1) is 97: 3 to 50: 50.   The polymer compound according to claim 1, 3 or 5, which is represented by the general formula (2), wherein m: n in the general formula (2) is 97: 3 to 50: 50. An organic photoelectric conversion device having a bulk hetero type photoelectric conversion layer, wherein the bulk hetero type photoelectric conversion layer comprises a polymer compound represented by the following general formula (1) or general formula (2) and a C [70] fullerene derivative Including, organic photoelectric conversion elements.

(In formula (1), Y represents a divalent structure units represented by the following formula (3) or formula (4), _{R 1} is each independently an alkyl group or a substituted alkyl having a carbon number of 1 to 16 represents a group, _{R 2} represents an alkyl group having a carbon number of 1 to 16, _{R 3} are each independently represented by a hydrogen atom or the following formula (8), at least one represented by the following formula (8) .R 'is an alkoxy group having a carbon number. 1 to 6, p is an integer of 1 to 5.
Moreover, in Formula (2), Y shows the bivalent structural unit represented by either of following formula (3), Formula (4), or Formula (6), R < ₁ > is carbon number independently, respectively. R ₁ represents an alkyl group of 1 to 16 or a substituted alkyl group, R ₂ represents an alkyl group having 1 to 16 carbon atoms, R ₃ is each independently a hydrogen atom or represented by the following formula (8), and at least one is It is represented by the following formula (8). R 'is a C1-C6 alkoxy group, p is an integer of 1-5.
m and n indicate the number of repeating units, m is 2 to 100, and n is 1 to 50.
In formula (4), R b represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 16 carbon atoms, or a substituted alkyl group, and in formula (3), k represents the number of repeating units and is 1 to 5. )

R ₁ in the general formula (1) are each independently an alkyl group or a substituted alkyl group having 1 to 16 carbon atoms, the formula (8) in the R 'is alkoxy group having a carbon number of 1 to 6 The organic photoelectric conversion element according to claim 8, wherein Y is a divalent constitutional unit represented by the formula (3) or the formula (4). R ₁ in the general formula (2) are each independently an alkyl group or a substituted alkyl group having 1 to 16 carbon atoms, the formula (8) in the R 'is alkoxy group having a carbon number of 1 to 6 The organic photoelectric conversion element according to claim 8, wherein Y is a divalent constitutional unit represented by the formula (3) or the formula (6). R ₁ in the general formula (1) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, p in the formula (8) is 1 and R ′ is a methoxy group, The organic photoelectric conversion element according to claim 8 or 9, wherein Y is a divalent constitutional unit represented by the following formula (9).
R ₁ in the general formula (2) is each independently an alkyl group having ₁ to 16 carbon atoms or a substituted alkyl group, p in the formula (8) is 1 and R ′ is a methoxy group, The organic photoelectric conversion element of Claim 8 or 10 whose Y is a bivalent structural unit represented by said Formula (6).   The mass ratio of the polymer compound represented by the general formula (1) or the general formula (2) constituting the bulk hetero type photoelectric conversion layer and the C [70] fullerene derivative is 1: 2 to 1: 5. The organic photoelectric conversion element according to any one of claims 8 to 12.   The organic photoelectric conversion device according to any one of claims 8 to 13, wherein the C [70] fullerene derivative is PC [70] BM. The bulk hetero type photoelectric conversion layer according to any one of claims 8 to 14, wherein the bulk hetero type photoelectric conversion layer contains at least one of an aliphatic thiol represented by the following general formula (I) and an iodine compound represented by the following general formula (II). The organic photoelectric conversion element as described in.
(Wherein, R _M represents an alkylene group having 3 to 15 carbon atoms, and R _N represents an alkylene group having 3 to 15 carbon atoms.)   The organic photoelectric conversion device according to claim 15, wherein the aliphatic thiol is octane dithiol and the iodine compound is diiodo octane.   The organic photoelectric conversion element according to any one of claims 8 to 16, wherein a transmittance of a visible light region of the bulk hetero type photoelectric conversion layer is 50 nm or more at a thickness of 100 nm. The bulk hetero-type photoelectric conversion layer has a thickness of 100 nm, and is measured with a C light source and 2 ° visual field conditions in the CIE (International Lighting Commission) L ^* a ^* b ^* color system specified in JIS Z 8729-1994. The organic photoelectric conversion device according to any one of claims 8 to 17, wherein the saturation C ^* value obtained is 10 or less.   The organic thin-film solar cell containing the organic photoelectric conversion element of any one of Claims 8-18. A method of manufacturing an organic photoelectric conversion device according to any one of claims 8 to 18, wherein an electrode serving as an anode is formed on a transparent substrate,
Forming a bulk hetero type photoelectric conversion layer containing the polymer compound represented by the general formula (1) or the general formula (2) and the C [70] fullerene derivative,
Forming an electrode to be a cathode;
The manufacturing method of an organic photoelectric conversion element containing.