JP2016089002A - Monomer and polymer having benzofuranothiophene skeleton, and organic thin-film solar cell material using the polymer - Google Patents

Abstract

（Ｒ^１〜Ｒ^５は各々独立にＨ、Ｃ１〜３０のアルキル基、分岐した炭素数１〜３０のアルキル基等；Ｘ^１〜Ｘ^３は各々独立に、Ｏ、Ｓ又はＳｅ、Ｎ−Ｒ^５；ｎは繰り返し数）
【選択図】なしDisclosed is a coating-type organic thin-film solar cell material excellent in photoelectric conversion efficiency.
A polymer containing a repeating unit represented by formula (1) or the like.

(R ^{1 to} R ⁵ are each independently H, C1-30 alkyl group, branched alkyl group having 1 to 30 carbon atoms, etc .; X ^{1 to} X ³ are each independently O, S or Se, N—R; ⁵ ; n is the number of repetitions)
[Selection figure] None

Description

  The present invention relates to a monomer and polymer having a benzofuranothiophene skeleton, an organic thin film solar cell material containing the polymer, and an organic thin film solar cell and apparatus using the material.

  Organic thin-film solar cells are devices that exhibit an electrical output with respect to light input, as represented by photodiodes and imaging devices that convert optical signals into electrical signals, and solar cells that convert optical energy into electrical energy. In particular, solar cells have attracted a great deal of attention as a clean energy source in recent years against the background of fossil fuel depletion and global warming, and research and development have been actively conducted. Conventionally, silicon solar cells represented by single crystal Si, polycrystal Si, amorphous Si, etc. have been put into practical use. However, as the cost and raw material Si shortage problems surface, The demand for next generation solar cells is increasing.

Crystal silicon is not only expensive, but must be deposited by sputtering. If the active layer of the solar cell can be formed by a high-speed process such as a coating method or a printing method, it is possible to produce an organic thin film solar cell at an overwhelmingly low cost compared to the conventional method.
From the above viewpoint, organic solar cell materials have been developed (Patent Document 1 and Non-Patent Document 1), but materials having further excellent performance have been demanded.

Three parameters indicating the performance of an organic thin film solar cell are important. That is, they are the short circuit current density (Jsc) (mA / cm ² ), the open circuit voltage (Voc) (V), and the fill factor (FF), and the product of these is the conversion efficiency (%).
For example, the p-type polymer material using the benzodithiophene skeleton of Non-Patent Document 2 has a Jsc of 9.79 (mA / cm ² ), Voc of 1.00 (V), FF of 0.63, conversion efficiency Was 6.17%. Since these performances are not always sufficient, improvement in conversion efficiency is required. In addition, in a device (module or the like) using an organic thin film solar cell, Voc and FF are particularly important parameters because the higher Voc and FF, the more advantageous the module design.

The polymers described in Patent Literature 1 and Non-Patent Literature 3 have Jsc of 13.51 (mA / cm ² ), Voc of 0.78 (V), FF of 0.61, and conversion efficiency of 6.42%. . In addition, even in the most studied PTB7 (Non-Patent Document 4), Jsc is 14.5 (mA / cm ² ), Voc is 0.74 (V), FF is 0.69, and conversion efficiency is 7.40. %.
Since these materials do not necessarily have sufficient Voc and conversion efficiency, further improvement in performance is required.

Chinese Patent Application No. 10936760

ORGANIC LETTERS 2013 Vol. 15, no. 21 5586-5589 Adv. Funct. Mater. 2013, 23, 885-892 J. et al. Mater. Chem. C, 2014, 2, 5651-5659 J. et al. AM. CHEM. SOC. 2009, 131, 7792-7799

  The objective of this invention is providing the coating type organic thin film solar cell material which can manufacture the organic thin film solar cell excellent in the photoelectric conversion efficiency.

（式（１）〜（５）中、Ｒ^１、Ｒ^２は、それぞれ独立に、水素原子、炭素数１〜３０のアルキル基、炭素数２〜３０のアルケニル基、炭素数２〜３０のアルキニル基である
Ｒ^３、Ｒ^４は、それぞれ独立に、分岐した炭素数１〜３０のアルキル基、分岐した炭素数２〜３０のアルケニル基、又は分岐した炭素数２〜３０のアルキニル基である。
Ｘ^１、Ｘ^２、Ｘ^４及びＸ^７は、それぞれ独立に、酸素原子、硫黄原子又はセレン原子である。
Ｘ^３は、それぞれ独立に、酸素原子、硫黄原子、セレン原子又はＮ−Ｒ^５である。
Ｘ^５及びＸ^６は、それぞれ独立に、酸素原子又は硫黄原子である。
Ｒ^５及びＲ^６、Ｒ^７は、水素原子、炭素数１〜３０のアルキル基、置換若しくは無置換の炭素数１〜３０のアルコキシ基、置換若しくは無置換の環形成炭素数６〜２０のアリール基、又は置換若しくは無置換の環形成原子数５〜２０のヘテロアリール基である。
ｎは繰り返し数を表す。）
２．前記式（１）又は（２）で表される繰り返し単位を含む１に記載のポリマー。
３．前記式（３）又は（４）で表される繰り返し単位を含む１に記載のポリマー。
４．下記式（１０）で表される繰り返し単位を含むポリマー。

（式（１０）中、Ｌ^１、Ｌ^２及びＡｒ^３は、それぞれ独立に、置換若しくは無置換の環形成炭素数６〜３０の芳香族炭化水素基又は置換若しくは無置換の環形成原子数３〜３０の複素芳香族環基である。
ｘ及びｙは、それぞれ独立に、０以上の整数である。
ｎは繰り返し数を表す。
Ａｒ^１及びＡｒ^２は、それぞれ独立に、下記式のいずれかで表される基である。

（式中、Ｘ及びＹは、それぞれ独立に、酸素原子、硫黄原子又はセレン原子である。
Ｒ^１０は、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、炭素数２〜５０のアルキニル基、炭素数１〜５０のアルコキシ基、炭素数１〜５０のチオアルキル基又は炭素数１〜５０のチオアルコキシ基である。
Ｒ^１１は、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、炭素数２〜５０のアルキニル基、又は炭素数１〜５０のアルコキシ基である。
ｐ１は０〜３の整数である。
ｐ２は０〜５の整数である。
ｐ３は０〜７の整数である。））
５．Ａｒ^３が下記式のいずれかで表される４に記載のポリマー。

（式中、Ｒは、それぞれ独立に、水素原子、フッ素原子、置換若しくは無置換の炭素数１〜３０のアルキル基、置換若しくは無置換の炭素数１〜３０のアルコキシ基、置換若しくは無置換の環形成炭素数６〜２０のアリール基、又は置換若しくは無置換の環形成原子数５〜２０のヘテロアリール基である。破線は結合手を示す。）
６．Ａｒ^３が下記式のいずれかで表される４に記載のポリマー。

（式中、Ｒは、それぞれ独立に、水素原子、フッ素原子、置換若しくは無置換の炭素数１〜３０のアルキル基、置換若しくは無置換の炭素数１〜３０のアルコキシ基、置換若しくは無置換の環形成炭素数６〜２０のアリール基、又は置換若しくは無置換の環形成原子数５〜２０のヘテロアリール基である。破線は結合手を示す。）
７．Ａｒ^３が下記式のいずれかで表される４に記載のポリマー。

（式中、Ｒは、それぞれ独立に、水素原子、フッ素原子、置換若しくは無置換の炭素数１〜３０のアルキル基、置換若しくは無置換の炭素数１〜３０のアルコキシ基、置換若しくは無置換の環形成炭素数６〜２０のアリール基又は置換若しくは無置換の環形成原子数５〜２０のヘテロアリール基である。破線は結合手を示す。）
８．ｘ及びｙが０である４〜７のいずれかに記載のポリマー。
９．ｘ及びｙが、それぞれ独立に、１以上の整数である４〜７のいずれかに記載のポリマー。
１０．ｘ及びｙが１であり、Ｌ^１及びＬ^２が下記式で表される４〜７のいずれかに記載のポリマー。

（式中、Ｘ及びＹは、それぞれ独立に、酸素原子、硫黄原子又はセレン原子である。
Ｒ^２０及びＲ^２１は、それぞれ独立に、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、又は炭素数２〜５０のアルキニル基である。）
１１．下記式（２０）で表されるモノマー。

（式（２０）中、Ａｒ^１及びＡｒ^２は、それぞれ独立に、置換若しくは無置換の環形成炭素数６〜３０の芳香族炭化水素基、置換若しくは無置換の環形成原子数５〜３０の複素芳香族環基、炭素数１〜３０のアルキル基、炭素数２〜３０のアルケニル基、又は炭素数２〜３０のアルキニル基である。
Ｒ^ａ及びＲ^ｂは、それぞれ独立に、Ｃｌ、Ｂｒ、Ｉ、−Ｓｎ（Ｒ^ｃ）_３、又は−Ｂ（ＯＲ’）（ＯＲ''）であり、Ｒ^ｃは、それぞれ独立に、炭素数４〜１２のアルキル基であり、Ｒ’及びＲ''は、それぞれ独立に、水素原子又は炭素数１〜１２のアルキル基であるか、又は、ＯＲ’及びＯＲ''は、ホウ素原子と共に炭素数２〜２４の環状基を形成する。）
１２．Ａｒ^１及びＡｒ^２が、置換若しくは無置換の炭素数１〜３０のアルキル基が置換したチオフェニル基ではない１２に記載のモノマー。
１３．Ａｒ^１及びＡｒ^２が、それぞれ独立に、下記式のいずれかで表される基である１１又は１２に記載のモノマー。

（式中、Ｘ及びＹは、それぞれ独立に、酸素原子、硫黄原子又はセレン原子である。
Ｒ^１０は、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、炭素数２〜５０のアルキニル基、炭素数１〜５０のアルコキシ基、炭素数１〜５０のチオアルキル基又は炭素数１〜５０のチオアルコキシ基である。
Ｒ^１１は、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、又は炭素数２〜５０のアルキニル基である。
ｐ１は０〜３の整数である。
ｐ２は０〜５の整数である。
ｐ３は０〜７の整数である。））
１４．Ｒ^ａ及びＲ^ｂが、それぞれ独立に、−Ｓｎ（Ｒ^ｃ）_３であり、Ｒ^ｃがノルマルブチル基である１１〜１３のいずれかに記載のモノマー。
１５．１〜１０のいずれかに記載のポリマーを含む有機薄膜太陽電池材料。
１６．１５に記載の有機薄膜太陽電池材料を含む活性層を有する有機薄膜太陽電池。
１７．１６に記載の有機薄膜太陽電池を具備する装置。 In order to achieve the above-mentioned problems, the present inventors have conducted intensive research. When a benzofuranothiophene skeleton in which the sulfur atom of the benzodithiophene skeleton is substituted with an oxygen atom is used, an aryl group or heteroaryl substituted at the 4,8-position It has been found that excellent performance is obtained by improving the planarity of the group. Furthermore, the present inventors have found that the conversion efficiency can be improved by using a benzofuranothiophene skeleton and a specific electron-withdrawing skeleton, and completed the present invention.
According to the present invention, the following polymers and the like are provided.
1. The polymer containing the repeating unit represented by either of following formula (1)-(5).

(In the formula ^{(1) ~ (5),} R 1, R 2 are each independently a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, alkynyl of 2 to 30 carbon atoms The groups R ³ and R ⁴ are each independently a branched alkyl group having 1 to 30 carbon atoms, a branched alkenyl group having 2 to 30 carbon atoms, or a branched alkynyl group having 2 to 30 carbon atoms.
X ¹ , X ² , X ⁴ and X ⁷ are each independently an oxygen atom, a sulfur atom or a selenium atom.
X ³ is each independently an oxygen atom, a sulfur atom, a selenium atom, or N—R ⁵ .
X ⁵ and X ⁶ are each independently an oxygen atom or a sulfur atom.
R ^5, R ⁶ and R ⁷ are each a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 ring carbon atoms. Or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms.
n represents the number of repetitions. )
2. 2. The polymer according to 1, comprising a repeating unit represented by the formula (1) or (2).
3. 2. The polymer according to 1, comprising a repeating unit represented by the formula (3) or (4).
4). The polymer containing the repeating unit represented by following formula (10).

(In Formula (10), L ¹ , L ² and Ar ³ are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms or a substituted or unsubstituted ring forming atom number 3. ˜30 heteroaromatic ring group.
x and y are each independently an integer of 0 or more.
n represents the number of repetitions.
Ar ¹ and Ar ² are each independently a group represented by any of the following formulae.

(In formula, X and Y are respectively independently an oxygen atom, a sulfur atom, or a selenium atom.
R ¹⁰ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, an alkoxy group having 1 to 50 carbon atoms, a thioalkyl group having 1 to 50 carbon atoms, or carbon. A thioalkoxy group having a number of 1 to 50.
R ¹¹ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, or an alkoxy group having 1 to 50 carbon atoms.
p1 is an integer of 0-3.
p2 is an integer of 0-5.
p3 is an integer of 0-7. ))
5. 5. The polymer according to 4, wherein Ar ³ is represented by any of the following formulae.

(In the formula, each R is independently a hydrogen atom, a fluorine atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted group. It is an aryl group having 6 to 20 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms. The broken line indicates a bond.)
6). 5. The polymer according to 4, wherein Ar ³ is represented by any of the following formulae.

(In the formula, each R is independently a hydrogen atom, a fluorine atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted group. It is an aryl group having 6 to 20 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms. The broken line indicates a bond.)
7). 5. The polymer according to 4, wherein Ar ³ is represented by any of the following formulae.

(In the formula, each R is independently a hydrogen atom, a fluorine atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted group. It is an aryl group having 6 to 20 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms. The broken line indicates a bond.)
8). The polymer according to any one of 4 to 7, wherein x and y are 0.
9. The polymer according to any one of 4 to 7, wherein x and y are each independently an integer of 1 or more.
10. The polymer according to any one of 4 to 7, wherein x and y are 1, and L ¹ and L ² are represented by the following formula.

(In formula, X and Y are respectively independently an oxygen atom, a sulfur atom, or a selenium atom.
R ²⁰ and R ²¹ are each independently an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, or an alkynyl group having 2 to 50 carbon atoms. )
11 A monomer represented by the following formula (20).

(In Formula (20), Ar ¹ and Ar ² are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom number of 5 to 30 atoms. It is a heteroaromatic ring group, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or an alkynyl group having 2 to 30 carbon atoms.
R ^a and R ^b are each independently Cl, Br, I, —Sn (R ^c ) ₃ , or —B (OR ′) (OR ″), and each R ^c is independently a carbon number 4 to 12 alkyl groups, and R ′ and R ″ are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, or OR ′ and OR ″ are carbon atoms together with a boron atom. A cyclic group of 2 to 24 is formed. )
12 13. The monomer according to 12, wherein Ar ¹ and Ar ² are not a thiophenyl group substituted by a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms.
13. The monomer according to 11 or 12, wherein Ar ¹ and Ar ² are each independently a group represented by any of the following formulae.

(In formula, X and Y are respectively independently an oxygen atom, a sulfur atom, or a selenium atom.
R ¹⁰ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, an alkoxy group having 1 to 50 carbon atoms, a thioalkyl group having 1 to 50 carbon atoms, or carbon. A thioalkoxy group having a number of 1 to 50.
R ¹¹ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, or an alkynyl group having 2 to 50 carbon atoms.
p1 is an integer of 0-3.
p2 is an integer of 0-5.
p3 is an integer of 0-7. ))
14 The monomer according to any one of 11 to 13, wherein R ^a and R ^b are each independently -Sn (R ^c ) ₃ and R ^c is a normal butyl group.
15. Organic thin-film solar cell material containing the polymer in any one of 1-10.
16. An organic thin film solar cell having an active layer containing the organic thin film solar cell material according to 16.15.
A device comprising the organic thin-film solar cell according to 17.16.

  ADVANTAGE OF THE INVENTION According to this invention, the coating type organic thin film solar cell material which can manufacture the organic thin film solar cell excellent in the photoelectric conversion efficiency can be provided.

式（１）〜（５）中、Ｒ^１、Ｒ^２は、それぞれ独立に、水素原子、炭素数１〜３０のアルキル基、炭素数２〜３０のアルケニル基、炭素数２〜３０のアルキニル基である。
Ｒ^３、Ｒ^４は、それぞれ独立に、分岐した炭素数１〜３０のアルキル基、分岐した炭素数２〜３０のアルケニル基、又は分岐した炭素数２〜３０のアルキニル基である。
Ｘ^１、Ｘ^２、Ｘ^４及びＸ^７は、それぞれ独立に、酸素原子、硫黄原子又はセレン原子である。
Ｘ^３は、それぞれ独立に、酸素原子、硫黄原子、セレン原子又はＮ−Ｒ^５である。
Ｘ^５及びＸ^６は、それぞれ独立に、酸素原子又は硫黄原子である。
Ｒ^５及びＲ^６、Ｒ^７は、水素原子、炭素数１〜３０のアルキル基、置換若しくは無置換の炭素数１〜３０のアルコキシ基、置換若しくは無置換の環形成炭素数６〜２０のアリール基、又は置換若しくは無置換の環形成原子数５〜２０のヘテロアリール基である。
ｎは繰り返し数を表す。 [polymer]
The 1st polymer of this invention contains the repeating unit represented by either of following formula (1)-(5).

In formulas (1) to (5), R ¹ and R ² are each independently a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or an alkynyl group having 2 to 30 carbon atoms. It is.
R ³ and R ⁴ each independently represent a branched alkyl group having 1 to 30 carbon atoms, a branched alkenyl group having 2 to 30 carbon atoms, or a branched alkynyl group having 2 to 30 carbon atoms.
X ¹ , X ² , X ⁴ and X ⁷ are each independently an oxygen atom, a sulfur atom or a selenium atom.
X ³ is each independently an oxygen atom, a sulfur atom, a selenium atom, or N—R ⁵ .
X ⁵ and X ⁶ are each independently an oxygen atom or a sulfur atom.
R ^5, R ⁶ and R ⁷ are each a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 ring carbon atoms. Or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms.
n represents the number of repetitions.

The first polymer of the present invention can obtain high conversion efficiency when used in an organic thin film solar cell by combining a specific electron-withdrawing skeleton with a benzofuranothiophene skeleton.
Here, since the azole compound has low solubility and poor applicability, R ³ and R ⁴ have a high conversion efficiency and are good by using a branched alkyl group, a branched alkenyl group or a branched alkynyl group. An organic thin film solar cell material having excellent coating properties was obtained.

  Although the repeating unit represented by Formula (1)-(5) may be any, the repeating unit represented by Formula (1) or (2) is preferable, and also represented by Formula (3) or (4). The repeating unit is also preferred.

R ¹ and R ² are preferably each independently a branched alkyl group having 1 to 30 carbon atoms.
R ³ and R ⁴ are preferably each independently a branched alkyl group having 1 to 30 carbon atoms.
X ^{1 to} X ⁴ are preferably sulfur atoms.
X ⁵ and X ⁶ are preferably each independently an oxygen atom.
R ⁵ and R ⁶ are preferably an alkyl group having 1 to 30 carbon atoms.

式（１０）中、Ｌ^１、Ｌ^２及びＡｒ^３は、それぞれ独立に、置換若しくは無置換の環形成炭素数６〜３０（好ましくは６〜２０）の芳香族炭化水素基又は置換若しくは無置換の環形成原子数３〜３０（好ましくは３〜２０）の複素芳香族環基である。
ｘ及びｙは、それぞれ独立に、０以上の整数である。
ｎは繰り返し数を表す。
Ａｒ^１及びＡｒ^２は、それぞれ独立に、下記式のいずれかで表される基である。

式中、Ｘ及びＹは、それぞれ独立に、酸素原子、硫黄原子又はセレン原子である。
Ｒ^１０は、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、炭素数２〜５０のアルキニル基、炭素数１〜５０のアルコキシ基、炭素数１〜５０のチオアルキル基又は炭素数１〜５０のチオアルコキシ基である。
Ｒ^１１は、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、炭素数２〜５０のアルキニル基、又は炭素数１〜５０のアルコキシ基である。
ｐ１は０〜３の整数である。
ｐ２は０〜５の整数である。
ｐ３は０〜７の整数である。 Moreover, the 2nd polymer of this invention contains the repeating unit represented by following formula (10).

In formula (10), L ¹ , L ² and Ar ³ are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 (preferably 6 to 20) ring-forming carbon atoms, or substituted or unsubstituted. A heteroaromatic cyclic group having 3 to 30 (preferably 3 to 20) ring-forming atoms.
x and y are each independently an integer of 0 or more.
n represents the number of repetitions.
Ar ¹ and Ar ² are each independently a group represented by any of the following formulae.

In the formula, X and Y are each independently an oxygen atom, a sulfur atom or a selenium atom.
R ¹⁰ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, an alkoxy group having 1 to 50 carbon atoms, a thioalkyl group having 1 to 50 carbon atoms, or carbon. A thioalkoxy group having a number of 1 to 50.
R ¹¹ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, or an alkoxy group having 1 to 50 carbon atoms.
p1 is an integer of 0-3.
p2 is an integer of 0-5.
p3 is an integer of 0-7.

The second polymer of the present invention has excellent solubility and coating properties by having predetermined substituents in Ar ¹ and Ar ² , and more suitable absorption wavelength and energy level. Therefore, the conversion efficiency is excellent.

Ｘ、Ｙ、Ｒ^１０、Ｒ^１１、ｐ１及びｐ２は、上記と同じである。 Ar ¹ and Ar ² are preferably each independently represented by any of the following formulae.

X, Y, R ¹⁰ , R ¹¹ , p1 and p2 are the same as described above.

X and Y are preferably each independently a sulfur atom.
R ¹⁰ is preferably an alkyl group having 8 to 24 carbon atoms or an alkoxy group having 8 to 24 carbon atoms.
R ¹¹ is preferably an 8-24 alkyl group.
p1 and p2 are preferably 0 or 1.

式中、Ｒは、それぞれ独立に、水素原子、フッ素原子、置換若しくは無置換の炭素数１〜３０のアルキル基、置換若しくは無置換の炭素数１〜３０のアルコキシ基、置換若しくは無置換の環形成炭素数６〜２０のアリール基、又は置換若しくは無置換の環形成原子数５〜２０のヘテロアリール基である。破線は結合手を示す。 Ar ³ is preferably represented by any of the following formulae.

In the formula, each R independently represents a hydrogen atom, a fluorine atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted ring. It is an aryl group having 6 to 20 carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms. A broken line shows a bond.

式中、Ｒ、破線は上記と同じである。 Ar ³ is more preferably represented by any one of the following formulas (i) to (iv). Among these, formula (i) or (ii) may be sufficient and formula (iii) or (iv) may be sufficient.

In the formula, R and a broken line are the same as above.

式（１１）中、Ａｒ^１〜Ａｒ^３、ｎは、前記式（１０）と同じである。 In the formula (10), x and y may be 0, or each may be an integer of 1 or more, for example, 1. That is, the second polymer of the present invention is preferably represented by the following formula (11) or (12).

In formula (11), Ar ^{1 to} Ar ³ and n are the same as those in formula (10).

In the formula (11), Ar ³ is preferably represented by the above formula (iii) or (iv).
In formulas (iii) and (iv), R is preferably a hydrogen atom, a fluorine atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, or a substituted group. Alternatively, it is an unsubstituted heteroaryl group having 5 to 20 ring atoms.

式（１２）中、Ａｒ^１〜Ａｒ^３、Ｌ^１及びＬ^２、ｎは、前記式（１０）と同じである。ｘ及びｙは、それぞれ独立に、１以上の整数であり、好ましくは１である。

In Formula (12), Ar ^{1 to} Ar ³ , L ¹ and L ² , and n are the same as those in Formula (10). x and y are each independently an integer of 1 or more, preferably 1.

In the formula (12), Ar ³ is preferably represented by the above formula (i) or (ii).

式中、Ｘ及びＹは、それぞれ独立に、酸素原子、硫黄原子又はセレン原子であり、好ましくは、硫黄原子である。即ち、Ｌ^１及びＬ^２は、好ましくは、それぞれ独立に、置換若しくは無置換の２価のチエニル基である。 In Formula (12), L ¹ and L ² are preferably represented by the following formula.

In the formula, X and Y are each independently an oxygen atom, a sulfur atom or a selenium atom, preferably a sulfur atom. That is, L ¹ and L ² are preferably each independently a substituted or unsubstituted divalent thienyl group.

R ²⁰ and R ²¹ are each independently an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, or an alkynyl group having 2 to 50 carbon atoms, preferably each independently having a carbon number It is a 1-30 alkyl group, More preferably, it is a C1-C15 alkyl group which has a linear or branched.

式中、Ｒ及び破線は、前記定義の通りである。 -(L ¹ ) _x -Ar ^3- (L ² ) _y- is preferably a group formed by combining the above examples of Ar ³ , L ¹ and L ^2. It is preferred that

In the formula, R and a broken line are as defined above.

  The weight average molecular weight of the first and second polymers of the present invention (hereinafter sometimes referred to as “the polymer of the present invention”) is preferably in the range of 20,000 to 500,000, More preferably, it is in the range of 000 to 200,000. The number average molecular weight is preferably in the range of 10,000 to 300,000, and more preferably in the range of 10,000 to 200,000.

The 1st polymer of this invention should just have the structure represented by either of Formula (1)-(5), and may have a structure other than that. The 2nd polymer of this invention should just have a structure represented by Formula (10), and may have another structure.
The polymer of this invention can be manufactured by the method as described in the Example mentioned later, or the method according to this.

式（２０）中、Ａｒ^１及びＡｒ^２は、それぞれ独立に、置換若しくは無置換の環形成炭素数６〜３０の芳香族炭化水素基、置換若しくは無置換の環形成原子数５〜３０の複素芳香族環基、炭素数１〜３０のアルキル基、炭素数２〜３０のアルケニル基、又は炭素数２〜３０のアルキニル基である。
Ｒ^ａ及びＲ^ｂは、それぞれ独立に、Ｃｌ、Ｂｒ、Ｉ、−Ｓｎ（Ｒ^ｃ）_３、又は−Ｂ（ＯＲ’）（ＯＲ''）であり、Ｒ^ｃは、それぞれ独立に、炭素数４〜１２のアルキル基であり、Ｒ’及びＲ''は、それぞれ独立に、水素原子又は炭素数１〜１２のアルキル基であるか、又は、ＯＲ’及びＯＲ''は、ホウ素原子と共に炭素数２〜２４の環状基を形成する。
尚、「ホウ素原子と共に環状基を形成する」とは、ＢとＯＲ’とＯＲ''とが連なって１つの環を形成することを言う。 [monomer]
The monomer of the present invention is represented by the following formula (20).

In formula (20), Ar ¹ and Ar ² are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, a substituted or unsubstituted hetero ring having 5 to 30 ring atoms. An aromatic ring group, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or an alkynyl group having 2 to 30 carbon atoms.
R ^a and R ^b are each independently Cl, Br, I, —Sn (R ^c ) ₃ , or —B (OR ′) (OR ″), and each R ^c is independently a carbon number 4 to 12 alkyl groups, and R ′ and R ″ are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, or OR ′ and OR ″ are carbon atoms together with a boron atom. A cyclic group of 2 to 24 is formed.
“Forming a cyclic group together with a boron atom” means that B, OR ′, and OR ″ are linked to form one ring.

  The polymer of the present invention can be produced by using the monomer of the present invention for polymerization.

式中、Ｘ及びＹは、それぞれ独立に、酸素原子、硫黄原子又はセレン原子である。
Ｒ^１０は、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、炭素数２〜５０のアルキニル基、炭素数１〜５０のアルコキシ基、炭素数１〜５０のチオアルキル基又は炭素数１〜５０のチオアルコキシ基である。
Ｒ^１１は、炭素数１〜５０のアルキル基、炭素数２〜５０のアルケニル基、又は炭素数２〜５０のアルキニル基である。
ｐ１は０〜３の整数である。
ｐ２は０〜５の整数である。
ｐ３は０〜７の整数である。 Ar ¹ and Ar ² may be groups other than the thiophenyl group substituted with an alkyl group having 1 to 30 carbon atoms among the above groups.
Ar ¹ and Ar ² are preferably each independently a group represented by any one of the following formulae.

In the formula, X and Y are each independently an oxygen atom, a sulfur atom or a selenium atom.
R ¹⁰ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, an alkoxy group having 1 to 50 carbon atoms, a thioalkyl group having 1 to 50 carbon atoms, or carbon. A thioalkoxy group having a number of 1 to 50.
R ¹¹ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, or an alkynyl group having 2 to 50 carbon atoms.
p1 is an integer of 0-3.
p2 is an integer of 0-5.
p3 is an integer of 0-7.

Ar ¹ and Ar ² are preferably each independently represented by any of the following formulae.

X and Y are preferably each independently a sulfur atom.
R ¹⁰ is preferably an alkyl group having 8 to 24 carbon atoms or an alkoxy group having 8 to 24 carbon atoms.
R ¹¹ is preferably an 8-24 alkyl group.
p1 and p2 are preferably 0 or 1.

R ^a and R ^b are preferably each independently —Sn (R ^c ) ₃ , and R ^c is preferably a normal butyl group.
The monomer purity is very important when polymerizing the polymer. When R ^a and R ^b are methyl groups, they are eliminated immediately with a weak acid or a weak base, so that high purity cannot be obtained. Therefore R ^a and R ^b are handled relatively stable by the -SnBu _3, the degree of polymerization for high purity can be obtained a high quality polymer is obtained.

  The monomer of this invention can be manufactured by the method as described in the Example mentioned later.

Hereinafter, each group in the above formula will be described.
In this specification, the aromatic hydrocarbon ring includes a monocyclic aromatic hydrocarbon ring and a condensed aromatic hydrocarbon ring in which a plurality of hydrocarbon rings are condensed. The same applies to an aryl group (monovalent aromatic hydrocarbon ring group) and an arylene group (divalent aromatic hydrocarbon ring group).
The heteroaromatic ring includes a monocyclic heteroaromatic ring, a condensed heteroaromatic ring in which a plurality of heteroaromatic rings are condensed, and a condensed heteroaromatic ring in which an aromatic hydrocarbon ring and a heteroaromatic ring are condensed. Including. The same applies to a heteroaryl group (a monovalent heteroaromatic ring group) and a heteroarylene group (a divalent heteroaromatic ring group).

  In the present invention, hydrogen includes isotopes having different numbers of neutrons, that is, light hydrogen (protium), deuterium (deuterium), and tritium (tritium).

Alkyl groups include linear or branched ones, and examples of such alkyl groups include those having 1 to 30 carbon atoms (preferably 6 to 25 carbon atoms, more preferably 8 to 15 carbon atoms). For example, methyl group, ethyl group, propyl group, isopropyl group, n-butyl group, s-butyl group, isobutyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n Examples include -octyl group, 2-ethylhexyl group, 2-butyloctyl group, 2-hexyldecyl group, 2-octyldodecyl, 2-decyltetradecyl group, 3-butylnonyl group and the like.
Of these, n-hexyl group, n-octyl group, 2-ethylhexyl group, 2-butyloctyl group, 2-hexyldecyl group, 2-decyltetradecyl group and 3-butylnonyl group are preferable.
Examples of the branched alkyl group include those branched above.

Examples of the alkenyl group include those having 2 to 20 carbon atoms (preferably 2 to 10 carbon atoms), such as vinyl group, allyl group, 1-butenyl group, 2-butenyl group, 3-butenyl group, 1,3- Examples include butanedienyl group, 1-methylvinyl group, 1-methylallyl group, 1,1-dimethylallyl group, 2-methylallyl group, 1,2-dimethylallyl group and the like.
Examples of branched alkenyl groups include those branched above.

  Examples of the alkynyl group include those having 2 to 20 carbon atoms (preferably 2 to 10 carbon atoms), such as propargyl group and 3-pentynyl group.

The alkoxy group is represented as RO-, and examples of R include the above alkyl groups.
A thioalkyl group is represented as RS-, and examples of R include the alkyl groups described above.
The thioalkoxy group is represented as ROS-, and examples of R include the above alkyl groups.

Examples of the aryl group include those having 6 to 30 (preferably 6 to 18) ring-forming carbon atoms. Specifically, a phenyl group, a naphthyl group, an anthracenyl group, a phenanthryl group, a pyrenyl group, a chrysenyl group, a biphenyl group, Terphenyl group, quarterphenyl group, fluoranthenyl group, triphenylenyl group, fluorenyl group, spirofluorenyl group, 9,9-diphenylfluorenyl group, 9,9'-spirobi [9H-fluoren] -2-yl Group (spirobifluorenyl group), 9,9-dimethylfluorenyl group, benzo [c] phenanthrenyl group, benzo [a] triphenylenyl group, naphtho [1,2-c] phenanthrenyl group, naphtho [1,2 -A] triphenylenyl group, dibenzo [a, c] triphenylenyl group, benzo [b] fluoranthenyl group, etc. A phenyl group, a naphthyl group, a phenanthryl group, a biphenyl group, a terphenyl group, a fluoranthenyl group, a triphenylenyl group, a fluorenyl group, and a spirobifluorenyl group are preferable.
Examples of the arylene group and the aromatic hydrocarbon ring include those corresponding to the above.

Examples of the heteroaryl group (heteroaromatic ring group) include those having 5 to 30 ring atoms (preferably 5 to 18), and specifically include a thiophene ring, a thienothiophene ring, a furan ring, a pyrrole ring, Isoindole ring, benzofuran ring, isobenzofuran ring, benzothiophene ring, dibenzothiophene ring, benzosilol ring, dibenzosilol ring, isoquinoline ring, quinoxaline ring, phenanthridine ring, phenanthroline ring, phenoxazine ring, phenothiazine ring, phenoxathiin Ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, triazine ring, indole ring, quinoline ring, acridine ring, pyrrolidine ring, dioxane ring, piperidine ring, morpholine ring, piperazine ring, furan ring, thiophene ring, quinazoline ring , Carbazole ring, o Formed from sazole ring, oxadiazole ring, benzoxazole ring, thiazole ring, thiadiazole ring, benzothiazole ring, triazole ring, imidazole ring, benzimidazole ring, pyran ring, dibenzofuran ring, benzo [c] dibenzofuran ring and their derivatives Groups formed from thiophene ring, furan ring, pyrrole ring, dibenzofuran ring, dibenzothiophene ring and derivatives thereof are preferable.
Examples of the heteroarylene group and the heteroaromatic ring include those corresponding to the above.

  As the substituent of “substituted or unsubstituted”, in addition to each of the above groups, a halogen atom, a linear or branched alkylcarbonyl group having 1 to 30 carbon atoms, a linear or branched carbon number having 1 to 30 carbon atoms. Examples include an alkoxycarbonyl group, an amino group, a substituted or unsubstituted silyl group, a cyano group, and a nitro group. These substituents may be further substituted.

Examples of the halogen atom include fluorine, chlorine, bromine and iodine.
The alkylcarbonyl group is represented as RCO-, and examples of R include the above alkyl groups.
The alkoxycarbonyl group is represented as ROCO-, and examples of R include the above alkyl groups.
The amino group is represented as R ₂ N—, and examples of R include the above alkyl groups.
The substituted silyl group is represented as R ₃ Si—, and examples of R include the above alkyl groups.

The polymer of the present invention is specifically represented by the following exemplary compounds 1-1 to 12-7. The polymer of the present invention is not limited to these.
In the following exemplary compounds, R ′, R ″, and R ′ ″ each represent a hydrogen atom or an alkyl group having 1 to 30 carbon atoms. R ″ ″ represents a hydrogen atom or a fluorine atom.

Further, in the repeating units of these polymers, when the acceptor (L ¹ , Ar ³ and L ² sites in formula (10)) unit is asymmetrical, the bond with the unit consisting of the benzofuranothiophene skeleton is the acceptor unit. There are two modes including the case where the left and right are reversed. In the following exemplification, only one of these embodiments is shown. However, the present invention is not limited to this structure, and the other embodiment, that is, an embodiment in which the acceptor unit is horizontally reversed is also included as an exemplary compound.

[Organic thin film solar cell materials]
The polymer of the present invention can be used for an organic thin film solar cell material.
The organic thin-film solar cell material of the present invention may contain only the polymer of the present invention, or may contain other organic solar cell materials and other components in addition to the polymer of the present invention. Moreover, 1 type may be included among the polymers of this invention, and 2 or more types may be included.
The organic thin film solar cell material of the present invention can form a layer of an organic solar cell by a coating method such as a wet film forming method described later.

The organic thin-film solar cell material preferably contains a compound having a function as an electron acceptor (electron-accepting compound).
Examples of the electron-accepting compound include oxadiazole derivatives, anthraquinodimethane and its derivatives, benzoquinone and its derivatives, naphthoquinone and its derivatives, anthraquinone and its derivatives, tetracyanoanthraquinodimethane and its derivatives, fluorenone derivatives, Diphenyldicyanoethylene and derivatives thereof, diphenoquinone derivatives, metal complexes of 8-hydroxyquinoline and derivatives thereof, polyquinoline and derivatives thereof, polyquinoxaline and derivatives thereof, polyfluorene and derivatives thereof, perylene and derivatives thereof, fullerene and derivatives thereof, carbon nanotubes Phenanthroline derivatives such as 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline, and fullerene and its derivatives are particularly preferable.
A material having a high electron mobility is preferable, and a material having a low electron affinity is preferable. A sufficient open-circuit voltage (Joc) can be realized by combining materials having a low electron affinity.

（式（Ｉ）〜（IV）中、Ｒ^ａは、それぞれ独立に、アルキル基、アリール基、ヘテロアリール基、又はエステル構造を有する基である。Ｒ^ｂは、それぞれ独立に、アルキル基又はアリール基を表す。） Examples of fullerene and derivatives thereof include C60, C70, C84 and derivatives thereof. A fullerene derivative represents a compound in which at least a part of fullerene is modified.
Examples of fullerene derivatives include compounds represented by the following formulas (I) to (IV).

(In the formulas (I) to (IV), each R ^a is independently an alkyl group, an aryl group, a heteroaryl group, or a group having an ester structure. Each R ^b is independently an alkyl group or an aryl group. Represents a group.)

（式（Ｖ）中、ｕ１は１〜６の整数を表す。ｕ２は０〜６の整数を表す。Ｒ^ｃは、アルキル基、アリール基、又はヘテロアリール基を表す。）
アルキル基、アリール基、ヘテロアリール基は上記で説明したものと同様である。 Examples of the group having an ester structure include a group represented by the following formula (V).

(In formula (V), u1 represents an integer of 1 to 6. u2 represents an integer of 0 to 6. R ^c represents an alkyl group, an aryl group, or a heteroaryl group.)
The alkyl group, aryl group, and heteroaryl group are the same as those described above.

Specific examples of the C60 derivative include the following.

Specific examples of the C70 derivative include the following.

As an inorganic compound having a function as an electron acceptor, an inorganic semiconductor compound having an n-type characteristic can be given. Specifically, n-Si, GaAs, CdS, PbS, CdSe, InP, Nb ₂ O ₅ , Doping semiconductors and compound semiconductors such as WO ₃ and Fe ₂ O ₃ , titanium oxides such as titanium dioxide (TiO ₂ ), titanium monoxide (TiO), and dititanium trioxide (Ti ₂ O ₃ ), zinc oxide (ZnO) ), Tin oxide (SnO ₂ ), molybdenum oxide (MoO ₃ ) and the like, and one or more of these may be used in combination.

[Organic thin film solar cells]
The organic thin film solar cell of this invention uses said organic thin film solar cell material for an active layer. The cell structure of the organic thin-film solar battery of the present invention is not particularly limited as long as it has a structure containing the active layer between a pair of electrodes.
Moreover, the organic thin film solar cell of this invention is good also as one of the following structures.
The “p layer” and “p material” are layers or materials containing the polymer of the present invention, and the “n layer” and “n material” are layers or materials containing the above-described electron accepting compounds.
(1) Lower electrode / p layer / n layer / upper electrode (2) Lower electrode / p layer / mixed layer of p material and n material / n layer / upper electrode (3) Lower electrode / mixture of p material and n material Layer / Upper Electrode In the above configurations (1) and (2), the p layer and the n layer may be replaced.
Moreover, in each structure of said (1), (2), (3), you may provide a buffer layer between an electrode and an organic layer as needed. For example, as a specific example, when a buffer layer is provided in the configuration (1), a structure having the following configuration can be given.
(4) Lower electrode / buffer layer / p layer / n layer / upper electrode (5) Lower electrode / p layer / n layer / buffer layer / upper electrode (6) Lower electrode / buffer layer / p layer / n layer / buffer Layer / Top electrode

In the case where the buffer layer is provided in the configuration (3),
(7) Lower electrode / buffer layer / mixed layer of p material and n material / upper electrode (8) Lower electrode / mixed layer of p material and n material / buffer layer / upper electrode (9) Lower electrode / buffer layer / p A configuration in which a mixed layer of material and n material / buffer layer / upper electrode is used.
Hereinafter, each component will be briefly described.

[Active layer]
The organic thin film solar cell of the present invention preferably includes the organic thin film solar cell material of the present invention in the active layer.
The thickness of the active layer is usually 1 nm to 100 μm, preferably 2 nm to 1000 nm, more preferably 5 nm to 500 nm, and further preferably 20 nm to 200 nm.

The active layer may contain any additive other than the polymer of the present invention and the electron accepting compound. Examples of additives include 1,8-diode octane (DIO), 1-chloronaphthalene, 1,10-diiododecane, 1,4-diiodobutane, 1,6-diiodohexane, 1,8-octanedithiol, etc. Examples include halogen-containing aliphatic hydrocarbons and halogen-containing aromatic hydrocarbons.
The compounding amount of the additive is preferably 0 to 20% by weight, more preferably 0 to 10% by weight in the active layer forming solution.

  For the formation of the active layer, wet film forming methods such as spin coating, dip coating, casting, roll coating, flow coating, and ink jet can be applied. At this time, any solvent described later can be used.

[substrate]
The organic thin film solar cell of the present invention is usually formed on a substrate. The substrate is preferably one having mechanical and thermal strength and transparency. For example, there are a glass substrate and a transparent resin film. Transparent resin films include polyethylene, ethylene-vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, polypropylene, polystyrene, polymethyl methacrylate, polyvinyl chloride, polyvinyl alcohol, polyvinyl butyral, nylon, polyether ether ketone. , Polysulfone, polyethersulfone, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, polyvinyl fluoride, tetrafluoroethylene-ethylene copolymer, tetrafluoroethylene-hexafluoropropylene copolymer, polychlorotrifluoroethylene, Polyvinylidene fluoride, polyester, polycarbonate, polyurethane, polyimide, polyetherimide, polyimide, polypropylene, etc. It is.
In the case of an opaque substrate, the opposite electrode (that is, the electrode far from the substrate) is preferably a transparent electrode or a translucent electrode.

[Lower and upper electrodes]
The material for the lower electrode and the upper electrode is not particularly limited, and metals, conductive polymers, and the like can be used. The material of one of the pair of electrodes is preferably a material having a low work function. For example, metals such as lithium, sodium, potassium, rubidium, cesium, magnesium, calcium, strontium, barium, aluminum, scandium, vanadium, zinc, yttrium, indium, cerium, samarium, europium, terbium, ytterbium, and those metals An alloy of two or more of these metals, or one or more of those metals and one or more of gold, silver, platinum, copper, manganese, titanium, cobalt, nickel, tungsten, tin An alloy with metal, graphite, a graphite intercalation compound, or the like is used. Examples of the alloy include magnesium-silver alloy, magnesium-indium alloy, magnesium-aluminum alloy, indium-silver alloy, lithium-aluminum alloy, lithium-magnesium alloy, lithium-indium alloy, and calcium-aluminum alloy.

  Examples of the material for the transparent electrode or the semitransparent electrode include a conductive metal oxide film and a semitransparent metal thin film. Specifically, a film formed using a conductive material made of indium oxide, zinc oxide, tin oxide, and indium tin oxide (ITO), indium zinc oxide, etc., which is a composite thereof, NESA (Tin oxide), gold, platinum, silver, and copper are used, and ITO, indium / zinc / oxide, and tin oxide are preferable. Examples of the method for producing the electrode include a vacuum deposition method, a sputtering method, an ion plating method, a plating method, and the like. Moreover, you may use organic transparent conductive films, such as polyaniline and its derivative (s), polythiophene, and its derivative (s) as an electrode material.

（ＰＥＤＯＴ：ＰＳＳにおいて、ｎ及びｍは、それぞれ繰り返し数である。） [Buffer layer]
In general, organic thin film solar cells often have a thin total film thickness, and therefore, the upper electrode and the lower electrode are likely to be short-circuited, and the yield of cell fabrication often decreases. In such a case, it is preferable to prevent this by laminating a buffer layer.
As a preferable compound for the buffer layer, a compound having sufficiently high carrier mobility is preferable so that the short-circuit current does not decrease even when the film thickness is increased. For example, if it is a low molecular compound, the aromatic cyclic acid anhydride represented by NTCDA shown below etc. will be mentioned, and if it is a high molecular compound, poly (3,4-ethylenedioxy) thiophene: polystyrene sulfonate (PEDOT: PSS), polyaniline: camphorsulfonic acid (PANI: CSA), and other known conductive polymers.

(In PEDOT: PSS, n and m are the number of repetitions.)

The buffer layer can also have a role of preventing excitons from diffusing to the electrode and being deactivated. Inserting a buffer layer as an exciton blocking layer in this way is effective for increasing efficiency. The exciton blocking layer can be inserted on either the anode side or the cathode side, or both can be inserted simultaneously. In this case, as a preferable material for the exciton blocking layer, for example, a well-known material for a hole barrier layer or a material for an electron barrier layer for use in an organic electroluminescence element (organic EL element) can be used.
A preferable material for the hole blocking layer is a compound having a sufficiently large ionization potential, and a preferable material for the electron blocking layer is a compound having a sufficiently small electron affinity. Specifically, bathocuproin (BCP), bathophenanthroline (BPhen), and the like, which are well-known materials for organic EL device applications, can be used as the cathode-side hole barrier layer material.

An inorganic semiconductor compound may be used for the buffer layer, and doping of p-Si, n-Si, GaAs, CdS, PbS, CdTe, SiC, CdSe, InP, Nb ₂ O ₅ , WO ₃ , Fe ₂ O _3, etc. Semiconductors and compound semiconductors, and titanium oxides such as titanium dioxide (TiO ₂ ), titanium monoxide (TiO), dititanium trioxide (Ti ₂ O ₃ ), zinc oxide (ZnO), tin oxide (SnO ₂ ), oxidation Examples thereof include conductive oxides such as molybdenum (MoO ₃ ).

[Method of manufacturing organic thin film solar cell]
The formation of each layer of the organic thin film solar cell of the present invention is performed by a dry film formation method such as vacuum deposition, sputtering, plasma, ion plating, or wet film formation such as spin coating, dip coating, casting, roll coating, flow coating, and ink jet. The law can be applied.

  The thickness of each layer is not particularly limited, but is set to an appropriate thickness. Since it is generally known that the exciton diffusion length of an organic thin film is short, if the film thickness is too thick, the exciton is deactivated before reaching the heterointerface, resulting in low photoelectric conversion efficiency. If the film thickness is too thin, pinholes and the like are generated, so that sufficient diode characteristics cannot be obtained, resulting in a decrease in conversion efficiency. The normal film thickness is suitably in the range of 1 nm to 10 μm, but more preferably in the range of 5 nm to 0.2 μm.

  In the case of the dry film forming method, a known resistance heating method is preferable, and for forming the mixed layer, for example, a film forming method by simultaneous vapor deposition from a plurality of evaporation sources is preferable. More preferably, the substrate temperature is controlled during film formation.

  In the case of a wet film forming method, a material for forming each layer is dissolved or dispersed in an appropriate solvent to prepare a light-emitting organic solution to form a thin film, and any solvent can be used. For example, halogenated hydrocarbon solvents such as dichloromethane, dichloroethane, chloroform, carbon tetrachloride, tetrachloroethane, trichloroethane, chlorobenzene, dichlorobenzene, chlorotoluene, ether solvents such as dibutyl ether, tetrahydrofuran, dioxane, anisole, methanol, Alcohol solvents such as ethanol, propanol, butanol, pentanol, hexanol, cyclohexanol, methyl cellosolve, ethyl cellosolve, ethylene glycol, hydrocarbon solvents such as benzene, toluene, xylene, ethylbenzene, hexane, octane, decane, tetralin, Examples include ester solvents such as ethyl acetate, butyl acetate, and amyl acetate. Of these, hydrocarbon solvents or ether solvents are preferable. These solvents may be used alone or in combination. In addition, the solvent which can be used is not limited to these.

In any organic compound layer of the organic thin film solar cell, an appropriate resin or additive may be used for improving the film formability and preventing pinholes in the film.
Usable resins include polystyrene, polycarbonate, polyarylate, polyester, polyamide, polyurethane, polysulfone, polymethyl methacrylate, polymethyl acrylate, cellulose and other insulating resins and copolymers thereof, poly-N-vinyl. Examples thereof include photoconductive resins such as carbazole and polysilane, and conductive resins such as polythiophene and polypyrrole.
Examples of the additive include an antioxidant, an ultraviolet absorber, and a plasticizer.

[Equipment etc.]
The organic thin film solar cell of the present invention can be used as a power source or an auxiliary power source for various devices such as watches, mobile phones, and mobile personal computers, and electrical appliances. Combined with a secondary battery with a charging function, it can be used in the dark, and the application range can be expanded.

  EXAMPLES Hereinafter, although this invention is demonstrated using an Example, this invention is not limited to the following Example.

[Monomer synthesis]
Example 1 (Synthesis of Monomer A-4-1)
Monomer A-4-1 was prepared according to the following synthesis scheme.

(1) Synthesis of Compound A-1 A 500 mL flask was equipped with a dropping funnel, 3-furancarboxylic acid (670 mmol, 75 g) and 300 mL of dichloromethane were added and stirred at room temperature, and thionyl chloride (737 mmol, 88 g, 1.1 eq) was added. It was dripped. After the reaction for 12 hours, the reaction solution was cooled to 5 ° C. with an ice bath, and diethylamine (1.0 mol, 73 g, 1.5 eq) was added dropwise. After 1 hour, the reaction solution was filtered, and the solvent was removed from the filtrate using an evaporator. The resulting brown solution was purified by distillation under reduced pressure to obtain yellow oil A-1 (94 g, yield 84%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 7.71 (1H, d), 7.42 (1H, d), 6.59 (1H, s), 3.48 (4H, q), 1. 22 (6H, t)

(2) Synthesis of Compound A-2 Compound A-1 (119 mmol, 20 g) was placed in a 500 mL flask, and the inside of the system was depressurized with a vacuum pump to perform nitrogen substitution. 150 mL of THF was added and stirred, and 1.6M n-BuLi hexane solution (119 mmol, 74 mL, 1.0 eq) was added dropwise at −68 ° C. 15 minutes after dropping, 3-thiophenaldehyde (119 mmol, 13.3 g, 1.0 eq) was added dropwise at −68 ° C., and the mixture was stirred at −68 ° C. for 2 hours. Further, 1.6M n-BuLi hexane solution (119 mmol, 72 mL, 1.0 eq) was added dropwise at −68 ° C., and the mixture was slowly returned to room temperature and stirred for 2 hours. Next, 50 ml of acetic acid and 20 ml of ethanol were added to the reaction solution and stirred for 10 minutes. The solution was concentrated, and the precipitated solid was filtered to obtain a yellow solid A-2 (6.3 g, yield 26%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 7.71 (1H, d), 7.67 (1H, d), 7.62 (1H, d), 6.95 (1H, d)

(3) Synthesis of Compound A-0-1 Thiophene (119 mmol, 10 g) was placed in a 500 mL flask, and the atmosphere was replaced with nitrogen under reduced pressure. Then, 240 mL of tetrahydrofuran (THF) was added and stirred at room temperature. After cooling to −78 ° C., 1.6 M n-butyl (n-Bu) Li hexane solution (119 mmol, 74 mL) was added dropwise over 20 minutes, and the mixture was reacted at −78 ° C. for 2 hours. Then, a 20 mL THF solution of 2-ethylhexyl bromide (119 mmol, 23 g) was added dropwise at −78 ° C. After dropping, the mixture was reacted for 4 hours while returning to room temperature and for 7 hours under reflux.
After removing the solvent from the obtained reaction solution using an evaporator, the residue was purified by silica column chromatography (hexane only), and further a colorless transparent oil of compound A-0-1 was obtained by distillation under reduced pressure (9.6 g, Yield 41%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , tetramethylsilane (TMS)) δ 7.10 (1H, dd), 6.90 (1H, t), 6.75 (1H, dd), 2.80 (2H, d), 1.60-1.62 (1H, m), 1.20-1.40 (8H, m), 0.84-0.91 (6H, m)

(4) Synthesis of Compound A-3-1 Compound A-0-1 (51.0 mmol, 10 g) was placed in a 500 mL flask, and the inside of the system was decompressed with a vacuum pump to perform nitrogen substitution. THF (100 mL) was added and stirred, and 1.6 M n-BuLi hexane solution (51.0 mmol, 32 mL) was added dropwise at 0 ° C. After dripping, it heated at 60 degreeC for 2 hours. Once the reaction solution was allowed to cool, A-2 (18.9 mmol, 3.9 g) was added and reacted under reflux for 4 hours. Then, a solution of tin (II) chloride dihydrate (147 mmol, 34 g) in 10% hydrochloric acid at 70 mL was added at room temperature and reacted for 2 hours.

The resulting reaction solution was washed twice with 100 mL of ion exchange water. The solvent of the organic layer was removed, and the resulting dark brown oil was purified by passing through silica gel column chromatography (hexane). Compound A-3-1 was obtained as a yellow oil (8.4 g, yield 79%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 7.88 (1H, d), 7.74 (1H, d), 7.48 (1H, d), 7.44 (1H, d), 7. 42 (1H, d), 7.18 (1H, d), 6.89 (1H, t), 2.85 (4H, d), 1.68 (2H, m), 1.34-1.45 (16H, m), 0.89-0.96 (12H, m)

(5) Synthesis of Monomer A-4-1 Compound A-3-1 (7.10 mmol, 4.0 g) was placed in a 100 mL flask and the atmosphere was replaced with nitrogen under reduced pressure, and then 70 ml of THF was added. A 1.6M n-BuLi hexane solution (14.9 mmol, 9.3 mL) was added dropwise at −68 ° C., and the temperature was slowly raised from −68 ° C. to room temperature. Next, tributyltin chloride (14.9 mmol, 4.8 g) was added at −68 ° C., and the temperature was slowly raised to room temperature. 50 mL of saturated aqueous ammonium chloride solution was added to the reaction solution and stirred, followed by extraction with 50 mL of hexane, and the organic layer was washed twice with 50 mL of saturated brine. The organic layer was dried over magnesium sulfate, and the residue obtained after removing the solvent was purified by silica gel column chromatography (hexane only) to obtain a yellow oil of monomer A-4-1 (7.9 g, yield 98%). . The silica gel used for the column was immersed in a mixed solution of hexane: triethylamine = 8: 2 for 20 minutes and sufficiently washed with hexane.
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 8.00 (1H, d), 7.51 (1H, d), 7.47 (1H, d), 7.28 (1H, s), 6. 89 (2H, t), 2.86 (4H, d), 1.55-1.75 (14H, m), 1.25-1.50 (40H, m), 1.12-1.20 ( 12H, m), 0.82-0.98 (36H, m)

In the above steps (3) to (5), different Ar monomers can be obtained by using various Ar—R as shown below. Specifically, it is as shown in Examples 2 and 3.

Example 2 (Synthesis of Monomer A-4-2)
Monomer A-4-2 was prepared according to the following synthesis scheme.

In Example 1 (4), A-0-2 (23.5 mmol, 5.9 g) was used instead of A-0-1, and in (5), A-3-1 was used instead of A-3-1. Monomer A-4-2 was synthesized in the same manner as in Example 1 except that 2 (6.07 mmol, 4.1 g) was used (7.45 g, yield 98%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 7.98 (1H, s), 7.65 (2H, d), 7.28 (1H, s), 7.02 (1H, s), 6. 98 (1H, s), 2.86 (4H, d), 1.55-1.70 (14H, m), 1.25-1.50 (40H, m), 1.12-1.20 ( 12H, m), 0.85-0.98 (36H, m)

Example 3 (Synthesis of Monomer A-4-3)
Monomer A-4-3 was prepared according to the following synthesis scheme.

In (4) of Example 1, A-0-3 (41.1 mmol, 7.4 g) was used in place of A-0-1, and A-3- in place of A-3-1 in (5). Monomer A-4-3 was synthesized in the same manner as in Example 1 except that 3 (5.65 mmol, 3.0 g) was used (5.95 g, yield 95%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 8.41 (1H, s), 7.53 (1H, s), 7.28 (1H, d), 7.06 (1H, d), 6. 26 (1H, d), 2.75 (4H, d), 1.55-1.90 (14H, m), 1.30-1.50 (40H, m), 1.20-1.30 ( 12H, m), 0.85-1.00 (36H, m)

Production Example 1 (Synthesis of Monomer B)
Monomer B was prepared according to the following synthesis scheme.

(1) Synthesis of Compound B-1 3,4-thiophenedicarboxylic acid (291 mmol, 50 g) and 200 mL of acetic anhydride were placed in a 500 mL flask and reacted with heating under reflux. After reacting for 4 hours, the reaction solution was concentrated under reduced pressure, allowed to cool, and then 200 mL of hexane was added. The precipitated light brown crystals were separated by filtration, further washed with hexane, and dried under reduced pressure to obtain Compound B-1 (43 g, yield 96%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 8.08 (2H, s)

(2) Synthesis of Compound B-2 Compound B-1 (77.0 mmol, 11.9 g) was placed in a 500-mL flask and purged with nitrogen under reduced pressure. 120 mL of dimethylformamide (DMF) was added, n-octylamine (83.9 mmol, 10.9 g) was added dropwise, and the mixture was further reacted for 3 hours under reflux.
To the obtained reaction solution, 360 mL of water was added, and the precipitated light brown crystals were separated by filtration. This was washed with hexane and dried to obtain Compound B-2 (15.8 g, yield 72%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 8.44 (1H, d), 7.92 (1H, d), 7.01 (1H, br), 3.44 to 3.49 (2H, m ), 1.63-1.67 (3H, m), 1.27-1.30 (10H, m), 0.86-0.89 (3H, m)

(3) Synthesis of Compound B-3 Compound B-2 (55.7 mmol, 15.8 g) and 70 mL of thionyl chloride were placed in a 300 mL flask and reacted under reflux for 3 hours.
When the reaction solution was poured little by little into 500 mL of 1N aqueous sodium hydroxide containing ice, brown crystals were precipitated. The obtained crystals were dissolved in 450 mL of methylene chloride, washed with 200 mL of saturated brine, and the organic layer was dried over magnesium sulfate. After magnesium sulfate was filtered off, the solvent was removed to obtain Compound B-3 (14.4 g, yield 97%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 7.80 (2H, s), 3.58-3.62 (2H, m), 1.60-1.65 (2H, m), 1.26 -1.32 (10H, m), 0.85-0.89 (3H, m)

(4) Synthesis of Monomer B Compound B-3 (54.1 mmol, 14.4 g), 83 mL of sulfuric acid and 270 mL of trifluoroacetic acid were placed in a 500 mL flask and stirred. N-bromosuccinimide (162.3 mmol, 28.9 g) was added in portions at room temperature. After completion of the addition, the reaction was allowed to proceed at room temperature for 6.5 hours under light shielding.
While cooling the flask with ice, 200 mL of water was added little by little to the resulting reaction solution and stirred. Extraction was performed with 400 mL of methylene chloride, and the organic layer was washed with 250 mL of saturated brine, 100 mL of 1N aqueous sodium hydroxide solution and then with 200 mL of water, and dried over magnesium sulfate. The obtained organic layer was purified by silica column chromatography (hexane: methylene chloride = 7: 3) to obtain white crystals of monomer B (15.2 g, yield 66%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 3.57-3.61 (2H, m), 1.57-1.64 (2H, m), 1.26-1.30 (10H, m) , 0.86-0.89 (3H, m)

Production Example 2 (Monomer C synthesis)
Monomer C was prepared according to the following synthesis scheme.

(1) Synthesis of Compound C-1 Into a 1000 mL flask was added triphenylphosphine (268.3 mmol, 70.3 g) and 400 mL of methylene chloride, and bromine (268.3 mmol, 13.8 mL) was added little by little while stirring at room temperature. Added. Next, 2-butyl-1-octanol (268.3 mmol) was added dropwise from the dropping funnel over 40 minutes at room temperature. The obtained reddish brown uniform solution was further reacted at room temperature for 10 hours.
The solvent was removed from the reaction solution, 400 mL of hexane was added, insoluble crystals were filtered off, and the insoluble material was washed with 100 mL of hexane. After removing hexane, the obtained yellow oil was purified by silica gel column chromatography (hexane only) to obtain a colorless transparent oil (63.8 g, yield 95%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 3.45 (2H, d), 1.58-1.60 (1H, m), 1.20-1.40 (16H, m), 0.87 -0.92 (6H, m)

(2) Synthesis of Compound C-2 Shaved Mg (131.5 mmol, 3.2 g) was placed in a 300 mL flask, and the reaction system was depressurized and purged with nitrogen. THF (10 mL) was added, and a THF (60 mL) solution of C-1 (120 mmol, 29.8 g) was added dropwise from the dropping funnel at room temperature over 1 hour. Subsequently, the reaction was carried out under reflux for 1 hour.
On the other hand, after putting NiCl ₂ (DPPP) ([1,3-bis (diphenylphosphino) propane] nickel (II) dichloride) (0.92 mmol, 0.49 g) into another 200 mL flask, 40 mL of THF and 3-bromothiophene (92 mmol, 15 g) were added and stirred at room temperature. To this solution, a THF solution of Grignard reagent prepared from A1-1 was placed under nitrogen and reacted under reflux for 6 hours.

Insoluble matter of the obtained reaction solution was filtered off, and the solvent was removed using an evaporator, followed by extraction with 200 mL of hexane and 100 mL of water, and the organic layer was dried over sodium sulfate. The residue obtained after removal of the solvent was purified by silica gel column chromatography (hexane only) to obtain a pale yellow oil of compound C-2 (19.7 g, yield 85%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 7.22 (1H, m), 6.88 (2H, m), 2.56 (2H, m), 1.61 (1H, m), 1. 18-1.35 (16H, m), 0.83-0.91 (6H, m)

(3) Synthesis of Compound C-3 The inside of a 500 mL flask equipped with a dropping funnel was decompressed and replaced with nitrogen. Under nitrogen, 200 mL of THF and compound C-2 (59.2 mmol, 14.9 g) were added, and 1.6M n-BuLi hexane solution (62.2 mmol, 38.9 mL) was added dropwise under cooling at −78 ° C. The mixture was reacted at −78 ° C. for 1 hour, and 2-isopropoxy-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (177.6 mmol, 36.2 mL) was added dropwise. After dropping, the mixture was stirred for 5 hours while returning to room temperature.
50 mL of saturated aqueous ammonium chloride solution was added to the reaction solution and stirred, followed by extraction with 100 mL of ethyl acetate, and the organic layer was washed with 100 mL of saturated brine. The organic layer was dried over sodium sulfate and the residue obtained after removing the solvent was purified by silica gel column chromatography (hexane: methylene chloride = 1: 1) to obtain a colorless translucent oil of compound C-3 (17.9 g). 80% yield).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 7.42 (1H, s), 7.17 (1H, s), 2.52-2.56 (2H, m), 1.59-1.61 (1H, m), 1.21-1.34 (28H, m), 0.79-0.89 (6H, m)

(4) Synthesis of Compound C-4 In a 500 mL flask, 4,7-diiodo-5,6-difluoro-2,1,3-benzothiadiazole (12.8 mmol, 5.5 g), Pd ₂ dba ₃ (Tris (di Benzylideneacetone) dipalladium (0)) (0.404 mmol, 0.37 g), tri-t-butylphosphine tetrafluoroborate (2.0 mmol, 0.58 g), potassium phosphate (81 mmol, 17.2 g) The inside of the system was depressurized and replaced with nitrogen. 200 mL of THF, compound C-3 (27.0 mmol, 10.3 g) and 1.3 mL of water were added and reacted under reflux for 7 hours.
After removing the solvent from the obtained reaction solution using an evaporator, extraction was performed with 400 mL of methylene chloride and 200 mL of saturated brine, and the organic layer was dried over sodium sulfate. Purification by silica column chromatography (hexane only) gave orange crystals of compound C-4 (7.8 g, yield 90.1%).
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 8.10 (2H, s), 7.19 (2H, s), 2.62 (4H, d), 1.69 (2H, br), 1. 27-1.31 (32H), 0.86-0.91 (12H, m)

(5) Synthesis of Monomer C N-bromosuccinimide (25.5 mmol, 4.5 g) was added little by little at room temperature to a 120 mL THF solution of compound C-4 (11.5 mmol, 7.8 g) placed in a 300 mL flask. . After completion of the addition, the reaction was allowed to proceed for 9 hours at room temperature.
The solvent was removed from the obtained reaction solution using an evaporator, and then purified twice by silica column chromatography (hexane only) to obtain orange crystals of monomer C (9.4 g, yield 97.7%). .
The measurement result of ¹ H-NMR is shown below.
¹ H-NMR (400 MHz, CDCl ₃ , TMS) δ 7.94 (2H, s), 2.60 (4H, d), 1.76 (2H, s), 1.27-1.31 (32H, m ), 0.85-0.91 (12H, m)

[Polymer synthesis]
Example 4 (Synthesis of Polymer 1)
Polymer 1 was prepared according to the following synthesis scheme.

Under a nitrogen atmosphere, 2.07 g (1.81 mmol, 1.0 eq.) Of the monomer A-4-1 obtained in Example 1, and 0.766 g (1.81 mmol, 1.0 eq.) Of the monomer B obtained in Production Example 1. ), Tris (dibenzylideneacetone) dipalladium (0) 16 mg (1.8 × 10 ⁻² mmol, Pd 2%), and tri (o-tolyl) phosphine 55 mg (1.8 × 10 ⁻¹ mmol, 0.1 eq) .) Was dissolved in 120 mL of anhydrous toluene and stirred at 140 ° C. for 24 hours. To the reaction mixture, 0.1 mL (0.55 mmol) of trimethylphenyltin was added and refluxed for 4 hours, and then 0.1 mL (0.94 mmol) of bromobenzene was added and refluxed for 4 hours. The reaction mixture was poured into 200 mL of methanol and the resulting precipitate was filtered off to obtain a dark purple solid. This solid was Soxhlet extracted with 150 mL of methanol for 4 hours, 150 mL of hexane for 4 hours, 150 mL of toluene for 3 hours, and 150 mL of chlorobenzene for 3 hours. The chlorobenzene extract was concentrated to obtain 0.47 g of polymer compound 1 (dark purple solid, 31%).

When the molecular weight measurement by high temperature GPC of the polymer 1 was performed under the following conditions, the MW (weight average molecular weight) was 168,800, the Mn (number average molecular weight) was 44,250, and the PDI (dispersion degree) was 3.82. It was.
Column: TOSOH GMHHR-H (S) HT
Column temperature: 145 ° C
Eluent: TCB (trichlorobenzene), 1.0 mL / min
Sample concentration: 0.15 weight / volume%
・ Punching amount: 160μL

Example 5 (Synthesis of Polymer 2)
Polymer 2 was synthesized in the same manner as in Example 4 except that monomer C (0.911 mmol, 0.654 g) was used instead of monomer B (0.911 mmol, 1.04 g). 73 g, yield 64%, MW: 105,600, Mn: 53,900, PDI: 1.95).

Example 6 (Synthesis of Polymer 3)
A polymer 3 was synthesized in the same manner as in Example 4 except that the monomer A-4-2 (0.866 mmol, 1.085 g) was used instead of the monomer A-4-1 in Example 4 (0.75 g). Yield 92%, MW (weight average molecular weight): 99,200, Mn (number average molecular weight): 26,500, PDI: 3.74).

Example 7 (Synthesis of Polymer 4)
In Example 4, monomer A-4-2 (0.855 mmol, 1.07 g) was used instead of monomer A-4-1 and monomer C (0.855 mmol, 0.831 g) was used instead of monomer B. The polymer 4 was synthesized in the same manner as in Example 4 (1.0 g, yield 87%, MW: 97,900, Mn: 55,800, PDI: 1.75).

Example 8 (Synthesis of Polymer 5)
In Example 4, Polymer 5 was synthesized in the same manner as Example 4 except that Monomer A-4-3 (1.22 mmol, 1.35 g) was used instead of Monomer A-4-1 (0.85 g). 88%, MW: 77,700, Mn: 45,200, PDI: 1.72).

Example 9 (Synthesis of Polymer 6)
In Example 4, the monomer A-4-3 (0.746 mmol 0.827 g) was used instead of the monomer A-4-1 and the monomer C (0.746 mmol, 0.619 g) was used instead of the monomer B. Was synthesized in the same manner as in Example 4 (0.88 g, yield 99%, MW: 95,600, Mn: 33,500, PDI: 2.85).

[Production and evaluation of organic solar cells]
Examples 10-15
The compounds used in Examples 10 to 15 are shown below.

(Preparation of ink)
Polymers 1 to 6 as a p-type semiconductor compound, and PC71BM (phenyl C71 butyric acid methyl ester, manufactured by American Dice Source (ADS), ADS71BFA) as an n-type semiconductor compound are mixed so that the weight ratio is 1: 1. The mixture was dissolved in a chlorobenzene solvent in a nitrogen atmosphere so as to have a concentration of 2.0% by weight. In addition, 1,8-diiodooctane (5 wt%) was added to this solution.
This solution was stirred and mixed on a hot stirrer at a temperature of 80 ° C. for 1 hour. The solution after stirring and mixing was filtered through a 0.45 μm polytetrafluoroethylene (PTFE) filter to obtain an ink.

(Production of organic solar cells: in the case of forward configuration)
A glass substrate with an ITO transparent electrode having a thickness of 25 mm × 25 mm × 0.7 mm was subjected to ultrasonic cleaning in isopropyl alcohol for 5 minutes, and then UV ozone cleaning was performed for 30 minutes. Next, a PEDOT: PSS solution (CleviosP VP AI4083 manufactured by Heraeus Co., Ltd.) was applied onto the ITO film by spin coating, and heated at 100 ° C. for 10 minutes in the atmosphere to form a buffer layer having a thickness of 40 nm. Next, the above ink was applied on the buffer layer by spin coating in a nitrogen atmosphere to obtain a functional layer of an organic thin film solar cell. The film thickness of the functional layer was 100 nm. Thereafter, lithium fluoride (LiF) was vapor-deposited with a film thickness of 1 nm by a vacuum vapor deposition machine, and then aluminum (Al) was vapor-deposited with a film thickness of 100 nm to produce an organic thin film solar cell. The area was 0.25 cm ² .

(Production of organic solar cells: reverse configuration)
A glass substrate with an ITO transparent electrode having a thickness of 25 mm × 25 mm × 0.7 mm was subjected to ultrasonic cleaning in isopropyl alcohol for 5 minutes, and then UV ozone cleaning was performed for 30 minutes. Next, a zinc oxide / isopropyl alcohol solution was applied onto the ITO film by spin coating, and heated at 200 ° C. in the atmosphere for 10 minutes to form a buffer layer. Next, the above ink was applied on the buffer layer by spin coating in a nitrogen atmosphere to obtain a functional layer of an organic thin film solar cell. The film thickness of the functional layer was 100 nm. Thereafter, molybdenum oxide was vapor-deposited with a vacuum vapor deposition machine, and then aluminum (Al) was vapor-deposited with a film thickness of 100 nm to produce an organic thin film solar cell. The area was 0.25 cm ² .

(Method for evaluating organic solar cells)
A 2 mm square metal mask is attached to the organic solar cell, a solar simulator with an air mass (AM) of 1.5 G and an irradiance of 100 mW / cm ² is used as an irradiation light source, and an ITO electrode is connected with a source meter (Keisley, Model 2400). The current-voltage characteristic between the aluminum electrode was measured. From this measurement result, open circuit voltage Voc (V), short circuit current density Jsc (mA / cm ² ), form factor FF, and photoelectric conversion efficiency PCE (%) were calculated. The results are shown in Table 1.
Here, the open circuit voltage Voc is a voltage value when the current value = 0 (mA / cm ² ), and the short circuit current density Jsc is a current density when the voltage value = 0 (V). The form factor FF is a factor representing the internal resistance, and is represented by the following expression when the maximum output is Pmax.
FF = Pmax / (Voc × Jsc)
Further, the photoelectric conversion efficiency PCE is given by the following equation when the incident energy is Pin.
PCE = (Pmax / Pin) × 100
= (Voc × Jsc × FF / Pin) × 100

Comparative Example 1
As a p-type semiconductor compound, an organic solar cell was prepared and evaluated in the same manner as in Example 1 except that the following polymer 7 described in Non-Patent Document 2 was synthesized and used. The results are shown in Table 1. This polymer had a weight average molecular weight of 130,400 and a number average molecular weight of 325,00.

Comparative Examples 2 and 3
The performance of the following compounds is cited from Patent Document 1. The device fabrication method is similar to that of the present example. PEDOT / PSS is applied on an ITO substrate, a mixed solution of polymer and PC71BM is applied thereon, and Al is deposited by vacuum deposition.
Table 1 shows the performance and the like.

  Table 1 shows that the polymer of this invention is excellent in conversion efficiency.

  The organic thin film solar cell of the present invention can be used as a power source or an auxiliary power source for various devices such as watches, mobile phones, and mobile personal computers, and electrical appliances. Combined with a secondary battery with a charging function, it can be used in the dark, and the application range can be expanded.

Claims (17)

The polymer containing the repeating unit represented by either of following formula (1)-(5).

(In the formula ^{(1) ~ (5),} R 1, R 2 are each independently a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, alkynyl of 2 to 30 carbon atoms The groups R ³ and R ⁴ are each independently a branched alkyl group having 1 to 30 carbon atoms, a branched alkenyl group having 2 to 30 carbon atoms, or a branched alkynyl group having 2 to 30 carbon atoms.
X ¹ , X ² , X ⁴ and X ⁷ are each independently an oxygen atom, a sulfur atom or a selenium atom.
X ³ is each independently an oxygen atom, a sulfur atom, a selenium atom, or N—R ⁵ .
X ⁵ and X ⁶ are each independently an oxygen atom or a sulfur atom.
R ^5, R ⁶ and R ⁷ are each a hydrogen atom, an alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 20 ring carbon atoms. Or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms.
n represents the number of repetitions. )   The polymer according to claim 1, comprising a repeating unit represented by the formula (1) or (2).   The polymer according to claim 1, comprising a repeating unit represented by the formula (3) or (4). The polymer containing the repeating unit represented by following formula (10).

(In Formula (10), L ¹ , L ² and Ar ³ are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms or a substituted or unsubstituted ring forming atom number 3. ˜30 heteroaromatic ring group.
x and y are each independently an integer of 0 or more.
n represents the number of repetitions.
Ar ¹ and Ar ² are each independently a group represented by any of the following formulae.

(In formula, X and Y are respectively independently an oxygen atom, a sulfur atom, or a selenium atom.
R ¹⁰ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, an alkoxy group having 1 to 50 carbon atoms, a thioalkyl group having 1 to 50 carbon atoms, or carbon. A thioalkoxy group having a number of 1 to 50.
R ¹¹ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, or an alkoxy group having 1 to 50 carbon atoms.
p1 is an integer of 0-3.
p2 is an integer of 0-5.
p3 is an integer of 0-7. )) The polymer according to claim 4, wherein Ar ³ is represented by any one of the following formulae.

(In the formula, each R is independently a hydrogen atom, a fluorine atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted group. It is an aryl group having 6 to 20 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms. The broken line indicates a bond.) The polymer according to claim 4, wherein Ar ³ is represented by any one of the following formulae.

(In the formula, each R is independently a hydrogen atom, a fluorine atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted group. It is an aryl group having 6 to 20 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms. The broken line indicates a bond.) The polymer according to claim 4, wherein Ar ³ is represented by any one of the following formulae.

(In the formula, each R is independently a hydrogen atom, a fluorine atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted group. It is an aryl group having 6 to 20 ring carbon atoms or a substituted or unsubstituted heteroaryl group having 5 to 20 ring atoms. The broken line indicates a bond.)   x and y are 0, The polymer in any one of Claims 4-7.   The polymer according to any one of claims 4 to 7, wherein x and y are each independently an integer of 1 or more. x and y is 1, the polymer according to any one of claims 4-7 which L ¹ and L ² is represented by the following formula.

(In formula, X and Y are respectively independently an oxygen atom, a sulfur atom, or a selenium atom.
R ²⁰ and R ²¹ are each independently an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, or an alkynyl group having 2 to 50 carbon atoms. ) A monomer represented by the following formula (20).

(In Formula (20), Ar ¹ and Ar ² are each independently a substituted or unsubstituted aromatic hydrocarbon group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted ring forming atom number of 5 to 30 atoms. It is a heteroaromatic ring group, an alkyl group having 1 to 30 carbon atoms, an alkenyl group having 2 to 30 carbon atoms, or an alkynyl group having 2 to 30 carbon atoms.
R ^a and R ^b are each independently Cl, Br, I, —Sn (R ^c ) ₃ , or —B (OR ′) (OR ″), and each R ^c is independently a carbon number 4 to 12 alkyl groups, and R ′ and R ″ are each independently a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, or OR ′ and OR ″ are carbon atoms together with a boron atom. A cyclic group of 2 to 24 is formed. ) The monomer according to claim 12, wherein Ar ¹ and Ar ² are not a thiophenyl group substituted by a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms. The monomer according to claim 11 or 12, wherein Ar ¹ and Ar ² are each independently a group represented by any of the following formulae.

(In formula, X and Y are respectively independently an oxygen atom, a sulfur atom, or a selenium atom.
R ¹⁰ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, an alkynyl group having 2 to 50 carbon atoms, an alkoxy group having 1 to 50 carbon atoms, a thioalkyl group having 1 to 50 carbon atoms, or carbon. A thioalkoxy group having a number of 1 to 50.
R ¹¹ is an alkyl group having 1 to 50 carbon atoms, an alkenyl group having 2 to 50 carbon atoms, or an alkynyl group having 2 to 50 carbon atoms.
p1 is an integer of 0-3.
p2 is an integer of 0-5.
p3 is an integer of 0-7. )) The monomer according to claim 11, wherein R ^a and R ^b are each independently —Sn (R ^c ) ₃ , and R ^c is a normal butyl group.   The organic thin-film solar cell material containing the polymer in any one of Claims 1-10.   The organic thin-film solar cell which has an active layer containing the organic thin-film solar cell material of Claim 15. The apparatus which comprises the organic thin-film solar cell of Claim 16.