阅读说明：本技术 有机半导体器件制造用油墨组合物 (Ink composition for manufacturing organic semiconductor device ) 是由 赤井泰之 横尾健 菱田真广 于 2020-04-06 设计创作，主要内容包括：本发明提供能够将具有刚性的主链骨架的有机半导体材料以最适于单晶形成工艺的溶质浓度进行油墨化的有机半导体器件制造用油墨组合物。该有机半导体器件制造用油墨组合物含有选自下述2,3-二氢苯并呋喃化合物(A)中的至少一种溶剂、和至少一种溶质。2,3-二氢苯并呋喃化合物(A)为下述式(a)表示的化合物。式(a)中,R～(1)、R～(2)、R～(3)、R～(4)、R～(5)及R～(6)参见说明书中的定义。(The invention provides an organic semiconductor material having a rigid main chain skeleton, which can be formed into a solute concentration optimum for a single crystal formation processAn ink composition for manufacturing an organic semiconductor device which is ink-jet processed. The ink composition for manufacturing an organic semiconductor device contains at least one solvent selected from the following 2, 3-dihydrobenzofuran compounds (A) and at least one solute. The 2, 3-dihydrobenzofuran compound (a) is a compound represented by the following formula (a). In the formula (a), R 1 、R 2 、R 3 、R 4 、R 5 And R 6 See definitions in the specification.)

1. An ink composition for manufacturing an organic semiconductor device, comprising:

at least one solvent selected from the following 2, 3-dihydrobenzofuran compounds (A), and

at least one kind of solute to be dissolved in the solution,

wherein the 2, 3-dihydrobenzofuran compound (A) is a compound represented by the following formula (a),

in the formula (a), R¹、R²、R³、R⁴、R⁵And R⁶Each represents a hydrogen atom, a halogen atom, or C optionally having a substituent selected from the following group 1_1-20Alkyl group, C optionally having a substituent selected from the following group 1_2-22Alkenyl group, C optionally having a substituent selected from the following group 1_2-22Alkynyl group, C optionally having a substituent selected from the following group 1_1-20Alkoxy group, C optionally having a substituent selected from the following group 1_1-20Alkylthio group of (1), C optionally having a substituent selected from the following group_2-20Alkylcarbonyl group, C optionally having substituent selected from the following group 1_2-20Alkoxycarbonyl group, di-or mono-C optionally having a substituent selected from the following group 1_1-20Alkylamino group, C optionally having a substituent selected from the following group 2_6-20Aryl group, 1-valent heterocyclic group optionally having substituent(s) selected from the following group 2, or C optionally having substituent(s) selected from the following group 2_3-20A cycloalkyl group,

group 1 is selected from: halogen atom, sulfonyl group, hydroxyl group, aldehyde group (-CHO), carbonyl group, carboxyl group, nitro group, amino group, sulfo group (-SO)₃H) Ether group, C_1-20Alkylthio, di-or mono-C_1-20Alkylamino radical, C_6-20Aryl, a 1-valent heterocyclic group, and C_3-20A substituted silyl group;

group 2 is selected from: a substituent selected from the group 1, C optionally having a substituent selected from the group 1_1-20Alkyl group, C optionally having a substituent selected from the group 1_2-20Alkenyl group, and C optionally having a substituent selected from the group 1_2-20Alkynyl.

2. The ink composition for organic semiconductor device production according to claim 1, wherein,

R¹、R²、R³、R⁴、R⁵and R⁶Each is a hydrogen atom, a halogen atom, or C optionally having a substituent selected from group 1_1-20An alkyl group.

3. The ink composition for organic semiconductor device production according to claim 1 or 2, wherein,

the 2, 3-dihydrobenzofuran compound (A) is 2, 3-dihydrobenzofuran.

4. The ink composition for organic semiconductor device production according to any one of claims 1 to 3, wherein,

the solute is an n-type organic semiconductor material.

5. The ink composition for organic semiconductor device production according to any one of claims 1 to 4, wherein,

the solute also contains a polymer compound as the component 2.

6. The ink composition for organic semiconductor device production according to any one of claims 1 to 5, which is used for producing an organic single-crystal semiconductor film by a drop casting method, an ink-jet printing method, an edge casting method, or a continuous edge casting method.

Technical Field

The invention of the present application relates to an ink composition for manufacturing an organic semiconductor device. More specifically, the present invention relates to an ink composition used for the production of an organic semiconductor device by a coating film formation method including a printing method. The present application claims priority to Japanese patent application No. 2019-077362, which was filed on 15.4.2019, the contents of which are incorporated herein by reference.

Background

In recent years, research and development have been conducted on organic semiconductors, oxide semiconductors, microcrystalline silicon semiconductors, low-temperature polycrystalline silicon semiconductors that can be solution-coated, and the like as candidates for a next-generation thin-film active device. In recent years, in order to establish an early market for Flexible substrate devices, development of Flexible Hybrid Electronics (FHE) in which printed Electronics using organic electronic materials or the like and conventional semiconductors, MEMS technologies, or the like are combined has been widely performed.

Organic semiconductors expected as a core technology of printed electronics have excellent characteristics that they have high mechanical strength against bending and can be formed by a low-temperature process and a coating method, and therefore, organic semiconductors are advantageous over other semiconductor materials in the production of devices using flexible substrates, and research and development for materials and devices for practical use have been widely conducted. In particular, an organic single crystal semiconductor film which realizes a high-performance organic semiconductor device has been attracting attention. As a technique for producing such an organic single crystal semiconductor film, a coating method such as an edge casting method and a continuous edge casting method has been proposed (patent document 1).

It is generally known that n-type organic semiconductor materials are more difficult to form crystalline thin films and to obtain high transistor characteristics (for example, carrier mobility) than p-type organic semiconductor materials. Conventionally, vapor deposition processes (such as vapor deposition) using large and high-volume equipment such as an ultra-high vacuum apparatus have been used for single crystallization and thin film formation of n-type organic semiconductor materials. However, in the film forming method using the ultrahigh vacuum apparatus, there is a limit to increase in area, and the manufacturing process itself becomes very expensive.

For this reason, a composition containing an n-type organic semiconductor material which can be produced by a coating method is required. For example, patent document 2 describes the use ofAnd (PDIs) represented by diimides (phenylene diimides)A composition for an organic thin film transistor, which is prepared by dissolving an organic compound having a bisimide skeleton in an organic solvent (anisole). It is reported that the carrier mobility of the organic thin film transistor manufactured by coating the composition is 1 × 10^-4cm²Over Vs.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2015-185620

Patent document 2: japanese patent laid-open publication No. 2018-006745

Disclosure of Invention

Problems to be solved by the invention

However, it is hard to say that the transistor characteristics of the organic thin film transistor using the composition for an organic thin film transistor of patent document 2 are sufficiently satisfactory. The reason for this is presumably becauseA low-molecular-weight n-type organic semiconductor material such as a bisimide skeleton has a condensed ring skeleton in which pi electrons are highly conjugated, and its solubility in a solvent is very low due to its rigid main chain skeleton structure, and it is difficult to produce a high-quality organic single-crystal thin film. That is, it is difficult to consider that the n-type organic semiconductor material to be blended is formed into an ink at a concentration optimum for the single crystal formation process in the conventional composition for an organic thin film transistor.

In view of the above circumstances, an object of the present invention is to provide an ink composition for manufacturing an organic semiconductor device, which can ink an n-type organic semiconductor material having a rigid main chain skeleton at a solute concentration optimal for a single crystal formation process.

Means for solving the problems

The present inventors have conducted intensive studies to solve the above problems, and as a result, have found that a specific benzofuran compound has high solubility in an n-type organic semiconductor material having a rigid main chain skeleton, and is suitable as a solvent capable of being inked with a solute concentration optimum for a single crystal formation process of the organic semiconductor material. The invention of the present application has been completed based on this finding.

That is, the present invention provides an ink composition for manufacturing an organic semiconductor device, which contains at least one solvent selected from the following 2, 3-dihydrobenzofuran compound (a), and at least one solute, wherein the 2, 3-dihydrobenzofuran compound (a) is a compound represented by the following formula (a).

[ chemical formula 1]

[ in the formula (a), R¹、R²、R³、R⁴、R⁵And R⁶Each represents a hydrogen atom, a halogen atom, or C optionally having a substituent selected from the following group 1_1-20Alkyl, optionally having a substituent selected from the group1 is C of substituent_2-22Alkenyl group, C optionally having a substituent selected from the following group 1_2-22Alkynyl group, C optionally having a substituent selected from the following group 1_1-20Alkoxy group, C optionally having a substituent selected from the following group 1_1-20Alkylthio group of (1), C optionally having a substituent selected from the following group_2-20Alkylcarbonyl group, C optionally having substituent selected from the following group 1_2-20Alkoxycarbonyl group, di-or mono-C optionally having a substituent selected from the following group 1_1-20Alkylamino group, C optionally having a substituent selected from the following group 2_6-20Aryl group, 1-valent heterocyclic group optionally having substituent(s) selected from the following group 2, or C optionally having substituent(s) selected from the following group 2_3-20A cycloalkyl group,

the above group 1 is selected from: halogen atom, sulfonyl group, hydroxyl group, aldehyde group (-CHO), carbonyl group, carboxyl group, nitro group, amino group, sulfo group (-SO)₃H) Ether group, C_1-20Alkylthio, di-or mono-C_1-20Alkylamino radical, C_6-20Aryl, a 1-valent heterocyclic group, and C_3-20A substituted silyl group, which is substituted with a silyl group,

the above group 2 is selected from: a substituent selected from the above group 1, C optionally having a substituent selected from the above group 1_1-20Alkyl group, C optionally having a substituent selected from the above group 1_2-20Alkenyl group, and C optionally having a substituent selected from the above group 1_2-20Alkynyl.]

In the above ink composition for producing an organic semiconductor device, R¹、R²、R³、R⁴、R⁵And R⁶Each is preferably a hydrogen atom, a halogen atom, or C optionally having a substituent selected from group 1_1-20An alkyl group.

In the ink composition for producing an organic semiconductor device, the 2, 3-dihydrobenzofuran compound (a) is preferably 2, 3-dihydrobenzofuran.

In the ink composition for manufacturing an organic semiconductor device, the solute may be an n-type organic semiconductor material.

The ink composition for producing an organic semiconductor device may further contain a polymer compound as the component 2 in addition to the solute.

The ink composition for manufacturing an organic semiconductor device can be used for manufacturing an organic single crystal semiconductor film by a drop casting (drop cast) method, an ink jet printing method, an edge casting method, or a continuous edge casting method.

ADVANTAGEOUS EFFECTS OF INVENTION

The ink composition for manufacturing an organic semiconductor device according to the present invention has the above-described configuration, and therefore, even when an n-type organic semiconductor material having a rigid main chain skeleton is used, it is possible to realize an ink concentration that exhibits excellent n-type semiconductor characteristics. Further, according to the ink composition for manufacturing an organic semiconductor device of the present application, it is possible to efficiently form a high-performance organic single crystal semiconductor element in a temperature range in which film formation by coating can be performed, and to efficiently form a highly reliable organic single crystal semiconductor film at low cost. Further, since the ink composition for manufacturing an organic semiconductor device of the present application can be applied by a coating method, an organic single crystal semiconductor film having high uniformity can be formed over a large area. Therefore, a high-performance flexible device that has not been available so far can be provided with high efficiency and at low cost using an organic thin film transistor.

Specifically, by using the ink composition for producing an organic semiconductor device of the present application and forming an organic single crystal semiconductor by a coating film-forming method such as a drop casting method, an ink jet printing method, an edge casting method, or a continuous edge casting method, a semiconductor device having a field-effect mobility μ p of 10[ cm ], [ mu ] p²/Vs]The above p-type transistor and μ n are 0.1[ cm [ ]²/Vs]And the flexible device of the high-performance organic CMOS circuit is formed by combining the n-type transistors.

Drawings

Fig. 1 is a diagram schematically showing a cross-sectional structure of an example of an organic thin film transistor.

Fig. 2 is a drawing showing the concept of an example of the continuous edge casting method.

Description of the symbols

100 temporary fixing substrate for processing

101 resin substrate

102 conductive film (gate electrode)

103 gate insulating film

104 organic semiconductor thin film

105 conductive film (Source electrode, Drain electrode)

106 charge injection layer for realizing ohmic junction

107 protective film

200 substrate table on which a substrate is to be placed on a continuous edge casting device

201 continuous edge cast coating/ink feed slot

202 ink tank

203 formed between the slit and the substrate, and a meniscus of the ink composition for manufacturing an organic device

Detailed Description

< ink composition for organic semiconductor device fabrication >

The ink composition for producing an organic semiconductor device (hereinafter, may be simply referred to as "the ink composition of the present application") is characterized by containing at least one solvent selected from the following 2, 3-dihydrobenzofuran compounds (a) and at least one solute.

2, 3-dihydrobenzofuran compound (a): a compound represented by the following formula (a).

[ chemical formula 2]

[ in the formula (a), R¹、R²、R³、R⁴、R⁵And R⁶Each represents a hydrogen atom, a halogen atom, or C optionally having a substituent selected from the following group 1_1-20Alkyl group, C optionally having a substituent selected from the following group 1_2-22Alkenyl group, C optionally having a substituent selected from the following group 1_2-22Alkynyl group, C optionally having a substituent selected from the following group 1_1-20Alkoxy group, optionally having a substituent selected from the following group 1C of (A)_1-20Alkylthio group of (1), C optionally having a substituent selected from the following group_2-20Alkylcarbonyl group, C optionally having substituent selected from the following group 1_2-20Alkoxycarbonyl group, di-or mono-C optionally having a substituent selected from the following group 1_1-20Alkylamino group, C optionally having a substituent selected from the following group 2_6-20Aryl group, 1-valent heterocyclic group optionally having substituent(s) selected from the following group 2, or C optionally having substituent(s) selected from the following group 2_3-20A cycloalkyl group.

The above group 1 is selected from: halogen atom, sulfonyl group, hydroxyl group, aldehyde group (-CHO), carbonyl group, carboxyl group, nitro group, amino group, sulfo group (-SO)₃H) Ether group, C_1-20Alkylthio, di-or mono-C_1-20Alkylamino radical, C_6-20Aryl, a 1-valent heterocyclic group, and C_3-20A substituted silyl group.

The above group 2 is selected from: a substituent selected from the above group 1, C optionally having a substituent selected from the above group 1_1-20Alkyl group, C optionally having a substituent selected from the above group 1_2-20Alkenyl group, and C optionally having a substituent selected from the above group 1_2-20Alkynyl.]

[2, 3-dihydrobenzofuran Compound (A) ]

The ink composition of the present application contains at least one selected from 2, 3-dihydrobenzofuran compounds (a) as the compounds represented by formula (a) above as a solvent. The 2, 3-dihydrobenzofuran compound (a) also exhibits high solubility in an n-type organic semiconductor material having a rigid main chain skeleton, and is suitable as a solvent capable of being inked with a solute concentration optimum for a single crystal formation process of the organic semiconductor material. The ink composition of the present application may contain only one kind of 2, 3-dihydrobenzofuran compound (a), or may contain two or more kinds of 2, 3-benzofuran compounds (a).

In the formula (a), R¹、R²、R³、R⁴、R⁵And R⁶Each represents a hydrogen atom, a halogen atom, C optionally having a substituent selected from the above group 1_1-20Alkyl, optionally substituted, selected from the above group 1C of radical_2-22Alkenyl, C optionally having a substituent selected from the above group 1_2-22Alkynyl, C optionally having a substituent selected from the above group 1_1-20Alkoxy group, C optionally having a substituent selected from the above group 1_1-20Alkylthio group of (5), C optionally having a substituent selected from the above group 1_2-20Alkylcarbonyl group, C optionally having substituent selected from the above group 1_2-20Alkoxycarbonyl, di-or mono-C optionally having a substituent selected from the above group 1_1-20Alkylamino group, C optionally having a substituent selected from the above group 2_6-20Aryl, a 1-valent heterocyclic group optionally having a substituent selected from the above group 2, or C optionally having a substituent selected from the above group 2_3-20A cycloalkyl group.

Examples of the "halogen atom" include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

As the above-mentioned "C_1-20Alkyl ", for example: a linear or branched alkyl group having 1 to 20 carbon atoms such as a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a tert-pentyl group, an n-hexyl group, an isohexyl group, a heptyl group, an octyl group, a nonyl group, and a decyl group.

As the above-mentioned "C_2-22Alkenyl ", for example: a linear or branched alkenyl group having 2 to 22 carbon atoms such as a vinyl group, 1-propenyl group, 2-methyl-1-propenyl group, 1-butenyl group, 2-butenyl group, 3-methyl-2-butenyl group, 1-pentenyl group, 2-pentenyl group, 3-pentenyl group, 4-methyl-3-pentenyl group, 1-hexenyl group, 3-hexenyl group, 5-hexenyl group, 1-heptenyl group, 1-octenyl group, 1-nonenyl group, 1-decenyl group, etc.

As the above-mentioned "C_2-22Alkynyl ", for example: a straight-chain or branched alkynyl group having 2 to 22 carbon atoms such as an ethynyl group, 1-propynyl group, 2-propynyl group, 1-butynyl group, 2-butynyl group, 3-butynyl group, 1-pentynyl group, 2-pentynyl group, 3-pentynyl group, 4-pentynyl group, 1-hexynyl group, 2-hexynyl group, 3-hexynyl group, 4-hexynyl group, 5-hexynyl group, 1-heptynyl group, 1-octynyl group, 1-nonynyl group, 1-decynyl group and the like.

As the above-mentioned "C_1-20Alkoxy ", for example, there may be mentioned: a straight-chain or branched alkoxy group having 1 to 20 carbon atoms such as a methoxy group, an ethoxy group, a n-propoxy group, an isopropoxy group, a n-butoxy group, an isobutoxy group, a sec-butoxy group, a tert-butoxy group, a n-pentoxy group, an isopentoxy group, a neopentoxy group, a tert-pentoxy group, a n-hexoxy group, an isohexoxy group, a heptoxy group, an octyloxy group, a nonyloxy group, and a decyloxy group.

As the above-mentioned "C_1-20Alkylthio ", for example: straight-chain or branched alkylthio groups having 1 to 20 carbon atoms such as a methylthio group, an ethylthio group, a n-propylthio group, an isopropylthio group, a n-butylthio group, an isobutylthio group, a sec-butylthio group, a tert-butylthio group, a n-pentylthio group, an isopentylthio group, a neopentylthio group, a tert-pentylthio group, a n-hexylthio group, an isohexylthio group, a heptylthio group, an octylthio group, a nonylthio group, and a decylthio group.

As the above-mentioned "C_2-20Alkylcarbonyl ", for example: a linear or branched alkylcarbonyl group having 2 to 20 carbon atoms such as an acetyl group, a propionyl group, an n-butyryl group, an isobutyryl group, an n-butylcarbonyl group, an isobutylcarbonyl group, a sec-butylcarbonyl group, a tert-butylcarbonyl group, an n-pentylcarbonyl group, an isopentylcarbonyl group, a neopentylcarbonyl group, a tert-pentylcarbonyl group, an n-hexylcarbonyl group, an isohexylcarbonyl group, a heptylcarbonyl group, an octylcarbonyl group, a nonylcarbonyl group, a decylcarbonyl group and the like.

As the above-mentioned "C_2-20Alkoxycarbonyl ", for example: a linear or branched alkoxycarbonyl group having 2 to 20 carbon atoms such as a methoxycarbonyl group, an ethoxycarbonyl group, a n-propoxycarbonyl group, an isopropoxycarbonyl group, a n-butoxycarbonyl group, an isobutoxycarbonyl group, a sec-butoxycarbonyl group, a tert-butoxycarbonyl group, a n-pentyloxycarbonyl group, an isopentyloxycarbonyl group, a neopentyloxycarbonyl group, a tert-pentyloxycarbonyl group, a n-hexyloxycarbonyl group, an isohexyloxycarbonyl group, a heptyloxycarbonyl group, an octyloxycarbonyl group, a nonyloxycarbonyl group, and a decyloxycarbonyl group.

As above-mentioned "di-or mono-C_1-20Alkylamino ", for example, there may be mentioned: methylamino, ethylamino, propylamino, isopropylamino, butylamino, isobutylamino, tert-butylamino, N-dimethylamino, N-di-aminoAn "C" for ethylamino, N-dipropylamino, N-diisopropylamino, N-dibutylamino, N-diisobutylamino, N-di-t-butylamino, N-methyl-N-ethylamino, etc_1-20Alkyl "mono-or di-substituted amino.

As the above-mentioned "C_6-20Aryl ", for example: and aryl groups with 6-20 carbon atoms such as phenyl, naphthyl, anthryl, phenanthryl, acenaphthenyl, biphenyl and the like.

Examples of the "1-valent heterocyclic group" include: a 5-to 22-membered (preferably 5-or 6-membered) aromatic heterocyclic group or non-aromatic heterocyclic group having a carbon atom and 1-to 4 hetero atoms selected from an oxygen atom, a sulfur atom and a nitrogen atom in the ring.

Examples of the aromatic heterocyclic group include: monocyclic aromatic heterocyclic groups such as furyl, thienyl, pyridyl, pyrrolyl, imidazolyl, pyrazolyl and thiazolyl; and condensed aromatic heterocyclic groups such as quinolyl and isoquinolyl.

Examples of the non-aromatic heterocyclic group include: monocyclic non-aromatic heterocyclic groups such as piperidyl, morpholinyl, piperazinyl and tetrahydrofuryl; and condensed non-aromatic heterocyclic groups such as chromenyl (chromenyl group), tetrahydroquinolyl, and tetrahydroisoquinolyl.

As the above-mentioned "C_3-20Cycloalkyl groups ", for example: and (c) a cyclic alkyl group having 3 to 20 carbon atoms such as a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclooctyl group, a cyclononyl group, or a cyclodecyl group.

Examples of the "sulfonyl group" include: "C_1-20Alkylsulfonyl group "," C_6-20Arylsulfonyl ", and the like.

As the above-mentioned "C_1-20Alkylsulfonyl ", there may be mentioned: methylsulfonyl, ethylsulfonyl, n-propylsulfonyl, isopropylsulfonyl, n-butylsulfonyl, isobutylsulfonyl, sec-butylsulfonyl, tert-butylsulfonyl, n-pentylsulfonyl, isopentylsulfonyl, neopentylsulfonyl, tert-pentylsulfonyl, n-hexylsulfonyl, isohexylsulfonyl, heptylsulfonyl, octylsulfonyl, nonylsulfonyl, decylsulfonylA linear or branched alkylsulfonyl group having 1 to 20 carbon atoms such as a alkylsulfonyl group.

As the above-mentioned "C_6-20Arylsulfonyl ", there may be mentioned, for example: arylsulfonyl groups having 6 to 20 carbon atoms such as phenylsulfonyl group, naphthylsulfonyl group, anthracenylsulfonyl group, phenanthrylsulfonyl group, acenaphthylsulfonyl group, biphenylsulfonyl group and the like.

Examples of the "carbonyl group" include: the above-mentioned "C_2-20Alkylcarbonyl group ", the above-mentioned" C_2-20Alkoxycarbonyl group and C_7-20Arylcarbonyl "and the like.

As the above-mentioned "C_7-20Arylcarbonyl ", for example: and arylcarbonyl groups having 7 to 20 carbon atoms such as benzoyl group, naphthylcarbonyl group, anthrylcarbonyl group, phenanthrylcarbonyl group, acenaphthylcarbonyl group, biphenylcarbonyl group and the like.

Examples of the "ether group" include: the above-mentioned "C_1-20Alkoxy group "," C_6-20Aryloxy groups "and the like.

As the above-mentioned "C_6-20Aryloxy ", for example: and aryloxy groups having 6 to 20 carbon atoms such as phenoxy, naphthoxy, anthracenoxy, phenanthrenoxy, acenaphthyloxy and biphenyloxy.

As the above-mentioned "C_3-20Substituted silyl groups, there may be mentioned: trimethylsilyl, triethylsilyl, t-butyldimethylsilyl, t-butyldiphenylsilyl, triisopropylsilyl and the like having a structure selected from the group consisting of the above-mentioned "C_1-20Alkyl radical "and the above-mentioned" C_6-20Aryl "1 to 3 (preferably 3) substituents of silyl.

The above-mentioned "C_1-20Alkyl group "," C_2-22Alkenyl group "," C_2-22Alkynyl group "," C_1-20Alkoxy group "," C_1-20Alkylthio group "," C_2-20Alkylcarbonyl group and C_2-20Alkoxycarbonyl ", and" di-or mono-C_1-20Alkylamino "optionally has a substituent selected from the above-mentioned group 1, the above-mentioned" C_6-20Aryl group "," 1-valent heterocyclic group ", and" C_3-20Cycloalkyl "optionally has a substituent selected from the above-mentioned group 2. The number of the substituents is not particularly limited, but is preferably 1 to 3. When 2 or more substituents are present, the 2 or more substituents may be the same or different.

R is as defined above¹、R²、R³、R⁴、R⁵And R⁶The respective substituents may be bonded to each other to further form a ring.

As R¹、R²、R³、R⁴、R⁵And R⁶From the viewpoint of solubility in a solute and easiness of acquisition of the 2, 3-dihydrobenzofuran compound (a), a hydrogen atom, a halogen atom, and C optionally having a substituent selected from the above group 1 are preferable_1-20Alkyl group, C optionally having a substituent selected from the above group 1_1-20Alkoxy, particularly preferably a hydrogen atom, C_1-20An alkyl group.

Preferred specific examples of the 2, 3-dihydrobenzofuran compound (a) include 2, 3-dihydrobenzofuran and 2, 3-dihydro-2-methylbenzofuran, and these may be used alone or in combination of two or more. Among these, 2, 3-dihydrobenzofuran is preferable from the viewpoints of solubility of an organic semiconductor material, film-forming properties of an organic single crystal semiconductor, and the like.

The proportion of the 2, 3-dihydrobenzofuran compound (a) in the entire solvent is, for example, 90% by weight or more, preferably 93% by weight or more, more preferably 95% by weight or more, and particularly preferably 100% by weight. When the ratio of the 2, 3-dihydrobenzofuran compound (a) in the entire solvent is not less than the lower limit value, the solubility of the organic semiconductor material and the film-forming property of the organic single-crystal semiconductor are more excellent. Therefore, particularly, it becomes easier to form an n-type organic semiconductor material into an ink having a solute concentration optimum for a single crystal formation process.

The purity of the 2, 3-dihydrobenzofuran compound (a) is, for example, 98.0% or more, preferably 98.5% or more, more preferably 99.0% or more, more preferably 99.5% or more, and particularly preferably 99.9% or more. Since the proportion of the organic semiconductor compound in the ink composition for an organic semiconductor device is very small, it is considered that impurities in the solvent largely affect the formation of the organic semiconductor single crystal film. When the purity of the 2, 3-dihydrobenzofuran compound (a) is 98.0% or more, a high-quality and beautiful film can be more easily formed. The purity of the 2, 3-dihydrobenzofuran compound (a) can be determined by Gas Chromatography (GC).

The reason why the solubility of the organic semiconductor material and the film-forming property of the organic single crystal semiconductor are more excellent than those of other general solvents (for example, hydrocarbon solvents such as hexane and octane, and ether solvents such as anisole) when the 2, 3-dihydrobenzofuran compound (a) is used as a solvent is not clearly understood, but is presumed as follows. Solvents used in ink compositions for organic semiconductor devices are required to have high solubility, high film-forming properties, and high printability. For example, in order to obtain high carrier mobility in an organic semiconductor device, it is necessary to control the film thickness of the organic semiconductor single crystal film. Therefore, high solubility is required for the solvent. In addition, since the ink composition for an organic semiconductor device is applied (formed) by printing, the volatility of a solvent during printing affects film-forming properties. For example, in the case of a solvent having a high boiling point (for example, 200 ℃ or higher), the volatility of the solvent is poor, a high-temperature printing process is required, deformation, breakage, and the like of the plastic substrate are taken into consideration, and in the case of a solvent having a low boiling point (for example, 100 ℃ or lower), the volatility is high, and therefore, it is difficult to maintain the concentration of the ink composition for an organic semiconductor device. Therefore, a solvent is required to have high film formability and high printability. The present inventors have studied a solvent suitable for an ink composition for an organic semiconductor device from a large number of solvents, and have found that the 2, 3-dihydrobenzofuran compound (a) has a good balance of high solubility, high film-forming property, and high printability, and can exhibit the above-described properties in a very good manner. Therefore, it is presumed that the solubility of the organic semiconductor material and the film forming property of the organic single crystal semiconductor are more excellent than those of other general solvents. However, the above description is merely an assumption, and certainly does not limit the invention of the present application.

The ink composition of the present application may contain a solvent (other solvent) other than the 2, 3-dihydrobenzofuran compound (a). Examples of the other solvent include solvents which are generally used for electronic materials and are compatible with the 2, 3-dihydrobenzofuran compound (a). The other solvent may contain one or two or more kinds. The proportion of the other solvent in the total solvent is, for example, 0 or more and less than 10% by weight, preferably 0 or more and less than 7% by weight, and more preferably 0 or more and less than 5% by weight. Among them, from the viewpoint of more effectively exerting the function of the 2, 3-dihydrobenzofuran compound (a) as a solvent, it is particularly preferable not to include other solvents (0 wt%).

The water content of the solvent used in the composition of the present application is preferably 0.25% by weight or less. It is presumed that when the water content in the composition of the present application is high, crystallization of the organic semiconductor material is inhibited, or moisture is trapped by carriers, and the carrier mobility tends to be lowered. The water content is preferably 0.19 wt% or less, and more preferably 0.05 wt% or less. The water content can be measured by the Karl-Fischer method.

[ solute ]

As the solute contained in the ink composition of the present application, a known n-type organic semiconductor material can be used without particular limitation.

The n-type organic semiconductor material contained as a solute in the ink composition of the present application is preferably a compound having a rigid main chain skeleton from the viewpoint of field-effect mobility and the like, and examples thereof include compounds represented by the following formula (1).

[ chemical formula 3]

[ in the formula (1), A¹¹And A¹²Each independently represents-O-, -N (R)^N) -or-P (R)^N)-。B¹¹～B¹⁸Each independently represents-N ═ or-C (R)^M)＝。R^NAnd R^MRepresents a hydrogen atom or a substituent. X¹¹～X¹⁴Each independently represents an oxygen atom or a sulfur atom.]

In the formula (1), A¹¹And A¹²Respectively represent-O-, -N (R)^N) -or-P (R)^N)-。A¹¹And A¹²Are each preferably-N (R)^N)-。A¹¹And A¹²Are optionally identical or different from each other, but are preferably identical and are more preferably both-N (R)^N)-。

R^NRepresents a hydrogen atom or a substituent. As useful as R^NThe substituent(s) is not particularly limited. Examples thereof include groups selected from the following substituent group Z.

Substituent group Z:

examples of the alkyl group include methyl, ethyl, propyl, 2-methylpropyl, butyl, pentyl (amyl), 2-dimethylpropyl, hexyl, 1-methylpentyl ((1S) -1-methylpentyl, (1R) -1-methylpentyl), heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, 2, 6-dimethyloctyl, Eicosyl, 2-decyltetradecyl, 2-hexyldodecyl, 2-ethyloctyl, 2-decyltetradecyl, 2-butyldecyl, 1-octylnonyl, 2-ethyloctyl, 2-octyldecyl, 2-octyldodecyl, 7-hexylpentadecyl, 2-octyltetradecyl, 2-ethylhexyl, cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, adamantyl, benzyl, p-chlorobenzyl, 2-phenylethyl, 3-phenylpropyl, trifluoromethyl, perfluoroethyl, 2,3,3,4,4, 4-heptafluorobutyl, C.sub.₅F₁₁C₂H₄-, 3-aminopropyl group, 4-aminobutyl group, 5-ethoxypentyl group, (meth) acryloyloxypropyl group, (meth) acryloyloxypentyl group, 4-hydroxybutyl group, 4-sulfobutyl group, 10-phosphonodecyl group, 2-hydroxyethoxymethyl group, 2-imidazolylethoxymethyl group, 4- (N, N-dimethylamino) butyl group), alkenyl group (the number of carbon atoms is preferably 2 to 20, more preferably 2 to 20)12. Particularly preferably 2 to 8, for example, vinyl, allyl, 2-butenyl, 1-pentenyl, 4-pentenyl, etc.), alkynyl (preferably 2 to 20, more preferably 2 to 12, particularly preferably 2 to 8, for example, propargyl, 1-pentynyl, trimethylsilylethynyl, triethylsilylethynyl, triisopropylsilylethynyl, 2-p-propylphenylethynyl, etc.), aryl (preferably 6 to 20, more preferably 6 to 12, for example, phenyl, naphthyl, 2,4, 6-trimethylphenyl, p- (tert-butyl) phenyl, 4-methyl-2, 6-dipropylphenyl, 4-fluorophenyl, 4-trifluoromethylphenyl, p-pentylphenyl, 3, 4-dipentylphenyl, p-heptyloxyphenyl, etc.), etc, 3, 4-diheptyloxyphenyl), heterocyclic group (also referred to as heterocyclic group). The ring-forming atoms include at least 1 or more hetero atoms and 1 to 30 carbon atoms. Examples of the hetero atom include: the number of nitrogen atoms, oxygen atoms and sulfur atoms is not particularly limited, and is, for example, 1 to 2. The number of the ring-forming carbon atoms is preferably 3 to 20, more preferably 3 to 12. The heterocyclic group is preferably a 5-or 6-membered ring or a fused ring thereof. The heterocyclic group includes an aromatic heterocyclic group (heteroaryl group) and an aliphatic heterocyclic group. Examples thereof include: thienyl, thiazolyl, imidazolyl, pyridyl, pyrimidyl, quinolyl, furyl, selenophenyl (C)₄H₃Se), piperidyl, morpholinyl, benzoAn azole group, a benzimidazole group, a benzothiazolyl group, a 2-hexylfuryl group, a pyranyl group, etc.), a silyl group (preferably having 3 to 40 carbon atoms, more preferably 3 to 30 carbon atoms, particularly preferably 3 to 24 carbon atoms), and examples thereof include: trimethylsilyl, triphenylsilyl, dimethylphenylsilyl, etc.), alkoxy (preferably 1 to 20, more preferably 1 to 12, particularly preferably 1 to 8 carbon atoms, for example, including methoxy, ethoxy, butoxy, etc.), amino (preferably 0 to 20, more preferably 0 to 10, particularly preferably 0 to 6 carbon atoms, for example: amino group, methylamino group, dimethylamino group, diethylamino group, dibenzylamino group, anilino group, etc.), aryloxy group (preferably having 6 to 20 carbon atoms, more preferablyPreferably 6 to 16, particularly preferably 6 to 12, and examples thereof include phenoxy group, 2-naphthoxy group and the like), acyl group (the number of carbon atoms is preferably 1 to 20, more preferably 1 to 16, particularly preferably 1 to 12, and examples thereof include: acetyl, hexanoyl, benzoyl, formyl, pivaloyl, etc.), alkoxycarbonyl (preferably 2 to 20, more preferably 2 to 16, and particularly preferably 2 to 12 carbon atoms), and examples thereof include: methoxycarbonyl group, ethoxycarbonyl group, etc.), an aryloxycarbonyl group (carbon number is preferably 7 to 20, more preferably 7 to 16, particularly preferably 7 to 10, and examples thereof include: phenoxycarbonyl group, etc.), an acyloxy group (the number of carbon atoms is preferably 2 to 20, more preferably 2 to 16, particularly preferably 2 to 10, and examples thereof include: acetoxy, benzoyloxy or (meth) acryloyloxy, etc.), acylamino group (preferably 2 to 20, more preferably 2 to 16, particularly preferably 2 to 10 in carbon number, for example, acetylamino group, benzoylamino group, etc.), aminocarbonylamino group (preferably 2 to 20, more preferably 2 to 16, particularly preferably 2 to 12 in carbon number, including ureyl group, etc.), alkoxy or aryloxycarbonylamino group (preferably 2(7) to 20, more preferably 2(7) to 16, particularly preferably 2(7) to 12 in carbon number). The number in parentheses indicates the number of carbon atoms in the case of an aryloxycarbonylamino group. Examples thereof include: methoxycarbonylamino group, phenoxycarbonylamino group, etc.), alkyl group, arylsulfonylamino group, alkylthio group (carbon number is preferably 1 to 20, more preferably 1 to 16, particularly preferably 1 to 12, and examples thereof include methylthio group, ethylthio group, octylthio group, etc.), arylthio group (carbon number is preferably 6 to 20, more preferably 6 to 16, particularly preferably 6 to 12, and examples thereof include: phenylthio, etc.), alkyl or arylsulfinyl, alkyl or arylsulfonyl, siloxy, heterocyclyloxy, carbamoyl, carbamoyloxy, heterocyclylthio, sulfamoyl, aryl or heterocycloazo, imido, phosphino, phosphinyl, phosphinyloxy, phosphinylamino, hydrazino, imino, cyano, hydroxy, nitro, mercapto, sulfo, carboxy, hydroxamato, sulfino, boronic acid (-B (OH)₂) Phosphate group (-OPO (OH)₂) Phosphono (-PO (OH)₂) Sulfuric acid radical (-OSO)₃H)。

Wherein the content of the first and second substances,as useful as R^NThe group selected from the substituent group Z is preferably an alkyl group, an aryl group, an alkenyl group, an alkynyl group, a heterocyclic group or a silyl group, more preferably an alkyl group (preferably having 1 to 20 carbon atoms), an aryl group (preferably having 6 to 20 carbon atoms) or a heteroaryl group (a group containing at least 1 or more of the above-mentioned heteroatoms as ring-constituting atoms, preferably a 5-or 6-membered ring or a condensed ring thereof, preferably a ring-constituting carbon number of 3 to 20), and still more preferably an alkyl group (particularly preferably a carbon number of 4 to 20).

The above-mentioned group selected from the substituent group Z also optionally has a further substituent. Examples of such a substituent include a group selected from substituent group Z. The number of optional substituents in the group further having a substituent (also referred to as a combined group) is not particularly limited, and is, for example, preferably 1 to 6, more preferably 1 to 3.

The group formed by the combination is not particularly limited, and examples thereof include groups in which the above-mentioned groups selected from the substituent group Z are preferably substituted with other groups selected from the substituent group Z. Specifically, examples thereof include an alkyl group, a halogenated aryl group, a (fluoro) alkylaryl group, and an alkynyl group having a silyl group as a substituent, each of which has a halogen atom, an alkyl group, an aryl group, a heterocyclic group (heteroaryl group), an alkoxy group (including a hydroxyalkoxy group, a halogenated alkoxy group, and a heteroarylalkoxy group), an amino group, an acyloxy group, a hydroxyl group, a sulfate group, and a phosphono group as a substituent. Further, there may be mentioned a group obtained by removing 1 hydrogen atom from the compound represented by the formula (1).

More specifically, the groups exemplified in the above substituent group Z, or the groups in the compounds used in the following exemplified compounds or examples may be cited.

Among the above groups, preferred is an alkyl group having a halogen atom as a substituent (haloalkyl group) or an alkyl group having an aryl group as a substituent, more preferred is an alkyl group having a fluorine atom as a substituent (fluoroalkyl group) or an alkyl group having an aryl group as a substituent, and particularly preferred is an alkyl group having an aryl group as a substituent.

As useful as R^NMore preferably an (unsubstituted) alkyl group, a haloalkyl group or an alkyl group having an aryl group as a substituent.

In A¹¹And A¹²Each has R^NIn the case of (2), R^NOptionally identical or different from each other.

In the formula (1), B¹¹～B¹⁸Each represents-N or-C (R)^M) Is as follows. Here, R^MRepresents a hydrogen atom or a substituent.

As useful as R^MThe substituent(s) is not particularly limited, and examples thereof include those selected from the above substituent group Z. A group selected from the substituent group Z optionally further has a substituent. Examples of such a substituent include a group selected from substituent group Z. As the group further having a substituent, there may be mentioned those which can be used as R^NSpecific examples of the group formed by combining the above groups include the above-mentioned groups and a group having a methine group bonded to a carbon atom of the compound represented by the formula (1).

As R^MPreferably, the halogen atom is a hydrogen atom, an alkyl group, an alkenyl group, an alkoxycarbonyl group, an aryl group, an alkoxy group, a heterocyclic group (particularly, a heteroaryl group), an amino group, a halogen atom, a cyano group, a carboxyl group, a nitro group or a mercapto group, more preferably a hydrogen atom, an alkyl group, an alkenyl group, an aryl group, an alkoxy group, a heterocyclic group (particularly, a heteroaryl group), a halogen atom or a cyano group, and particularly preferably a hydrogen atom, an alkyl group, an aryl group, a heterocyclic group (particularly, a heteroaryl group), a halogen atom or a cyano group.

Can be used as R^MThe substituent(s) may also form a ring. The form in which the substituent forms a ring includes a form in which the substituents are bonded to each other to form a ring and a form in which a plurality of the substituents share 1 atom to form a ring. Examples of the form in which the substituents are bonded to each other to form a ring include: 2 vinyl groups being bonded to each other and to R^MThe bonded carbon atoms together form the form of a benzene ring. Examples of the form in which a ring is formed by sharing 1 atom with a plurality of substituents include: the 2 substituents are integrated into the form of a sulfur atom (-S-group).

B¹¹～B¹⁸At least 1 of these is preferably-N-, preferably 1 to 4 are-N-, more preferably 1 or 2 are-N-, and particularly preferably 2 are-N-. In addition, B is also preferable¹¹～B¹⁸All are-C (R)^M) In the form of.

B which may be used is not particularly limited, and B¹¹～B¹⁸Any B in (a) may be-N ═ N. For example, B is preferred¹²、B¹³、B¹⁶And B¹⁷At least 1 of which is-N ═ more preferably B¹²And B¹⁶One or both of which is-N ═ N.

Can be used as B¹¹～B¹⁸The nitrogen atom of (a) may have a substituent. Examples thereof include: n-oxide groups (N → O groups), salts with counter anions, and the like.

In the formula (1), X¹¹～X¹⁴Each represents an oxygen atom or a sulfur atom, and preferably an oxygen atom. More preferably X¹¹～X¹⁴Are all oxygen atoms.

Here, A¹¹And A¹²And X¹¹～X¹⁴The combination of (A) is not particularly limited, but A is preferred¹¹And A¹²is-N (R)^N)-、X¹¹～X¹⁴Is a combination of oxygen atoms.

The compound represented by the formula (1) is particularly preferably at least one compound selected from the compounds represented by the following formulae (1-1) to (1-5) in view of having high carrier mobility.

A compound represented by the formula (1-1): n, N' -bis (3-phenylpropyl) pyrene-3, 4,9, 10-dicarbodiimide

A compound represented by the formula (1-2): n, N' -bis (2-phenylethyl) pyrene-3, 4,9, 10-dicarbodiimide

A compound represented by the formula (1-3): n, N' -bis (octyl) pyrene-3, 4,9, 10-dicarboximide (C8PDI)

A compound represented by the formula (1-4): 2, 9-bis (2,2,3,3,4,4, 4-heptafluorobutyl) -1,2,3,8,9, 10-hexahydro-1, 3,8, 10-tetraoxaanthraco [2,1,9-def:6,5,10-d ' e ' f ' ] bisisoquinoline-5, 12-dinitrile (PDI-FCN2(1,7))

A compound represented by the formula (1-5): 2, 9-bis [ (1S) -1-methylpentyl ] -1,2,3,8,9, 10-hexahydro-1, 3,8, 10-tetraoxaanthraco [2,1,9-def:6,5,10-d ' e ' f ' ] bisisoquinoline-5, 12-dinitrile (PDI1MPCN2(1,7))

[ chemical formula 4]

The compound represented by the above formula (1) can be produced by the production method described in International publication No. 2011/082234 and Japanese patent application laid-open No. 2018-006745, and a commercially available product can be used.

The compound represented by the above formula (1) has a main chain skeleton which is rigidSince the imide nitrogen at both ends of the imide skeleton is substituted with a substituent, the imide skeleton has high solubility in the 2, 3-dihydrobenzofuran compound (a) and is less likely to precipitate even in a low-temperature environment.

As another example of the n-type organic semiconductor material contained as the solute in the ink composition of the present application, a compound having a naphthalene diimide skeleton as a rigid main chain skeleton is also preferable, and examples thereof include a compound represented by the following formula (2) and a compound represented by the following formula (3).

[ chemical formula 5]

[ in the above formula (2), A²¹And A²²Each independently represents-N (R)^N1)-、-P(R^N1) -, or-O-. R^N1Represents a hydrogen atom or a substituent. Plural R^N1Each of which may be the same or different.

In the above formula (2), B²¹And B²²Each independently represents-N ═ or-C (R)^M1)＝。R^M1Represents a hydrogen atom or a substituent. B is²¹And B²²All are-C(R^M1) When not satisfied, B²¹R contained in (1)^M1And B²²R contained in (1)^M1A ring may be formed.

In the above formula (2), Ch²¹Represents a sulfur atom, a sulfinyl group, a sulfonyl group, a selenium atom, a selenoylgroup, or-B²³-B²⁴-a group represented by (a). B is²³And B²⁴Each independently represents-N ═ or-C (R)^M2)＝。R^M2Represents a hydrogen atom or a substituent. B is²³And B²⁴Are all-C (R)^M2) When not satisfied, B²³R contained in (1)^M2And B²⁴R contained in (1)^M2A ring may be formed.

In the above formula (2), X²¹、X²²、X²⁴And X²⁵Each independently represents an oxygen atom or a sulfur atom.

In the above formula (3), A³¹And A³²Each independently represents-N (R)^N1)-、-P(R^N1) -, or-O-. R^N1Represents a hydrogen atom or a substituent. Plural R^N1Each of which may be the same or different.

In the above formula (3), B³¹And B³²Each independently represents-N ═ or-C (R)^M1)＝。R^M1Represents a hydrogen atom or a substituent. B is³¹And B³²Are all-C (R)^M1) When not satisfied, B³¹R contained in (1)^M1And B³²R contained in (1)^M1A ring may be formed.

In the above formula (3), Ch³¹Represents a sulfur atom, a sulfinyl group, a sulfonyl group, a selenium atom, a selenoylgroup or a selenoylgroup.

In the above formula (3), X³¹、X³²、X³⁴And X³⁵Each independently represents an oxygen atom or a sulfur atom.

In the above formula (3), R³¹And R³²Each independently represents a hydrogen atom or a substituent.]

A in the above formula (2)²¹And A²²Each independently represents-N (R)^N1)-、-P(R^N1) -or-O-. Of these, from further improvement in carrier mobilityFrom the viewpoint of A²¹And A²²Are each independently preferably-N (R)^N1) -or-P (R)^N1) -, more preferably-N (R)^N1)-。R^N1Represents a hydrogen atom or a substituent. Plural R^N1Each of which may be the same or different. As R^N1The substituent represented by (a) is not particularly limited, and examples thereof include those selected from the above substituent group Z. From the viewpoint of further improving the carrier mobility, a²¹And A²²Preferably the same groups.

Wherein R is^N1Preferably a hydrogen atom, a silyl group, a heterocyclic group, an aryl group, an alkynyl group, or a linear, branched or cyclic alkyl group. Each group other than a hydrogen atom may be further substituted with a substituent selected from the above substituent group Z. Of these, R is from the viewpoint of further improving the carrier mobility^N1Preferably a C1-20 linear, branched or cyclic alkyl group, a C6-20 aryl group or a C3-20 heteroaryl group, more preferably a C1-20 linear, branched or cyclic alkyl group. Each group may be further substituted with a substituent selected from the above substituent group Z. Further, from the viewpoint of further improving the carrier mobility, R is^N1More preferably a cyclic alkyl group (cycloalkyl group) having 3 to 8 carbon atoms (preferably 4 to 7 carbon atoms, and more preferably 5 to 6 carbon atoms), and particularly preferably a cyclohexyl group.

In the formula (2), B²¹And B²²Each independently represents-N ═ or-C (R)^M1) Is as follows. From the viewpoint of further improving atmospheric stability, B is preferable²¹And B²²Two of (A) are-C (R)^M1) Or one is-N and the other is-C (R)^M1) More preferably, both are-C (R)^M1)＝。B²¹And B²²Are all-C (R)^M1) When not satisfied, B²¹R contained in (1)^M1And B²²R contained in (1)^M1A ring may be formed. When a ring is formed, an aromatic heterocyclic ring or an aromatic hydrocarbon ring is preferable, and a benzene ring is more preferable. In addition, B is²¹Contained inR^M1And B²²R contained in (1)^M1When a ring is formed, the ring may have a substituent selected from the above substituent group Z, and the substituents may be bonded to each other to form a further ring. R^M1Represents a hydrogen atom or a substituent. In the formula (2), a plurality of R's are present^M1When a plurality of R^M1Each of which may be the same or different. As R^M1The substituent represented by (a) is not particularly limited, and examples thereof include those selected from the above substituent group Z. In these, R^M1The alkyl group is preferably a hydrogen atom, a halogen atom, a haloalkyl group, a cyano group, a nitro group, an alkoxy group, an alkoxycarbonyl group, a carboxyl group, a heterocyclic group, or an amino group, more preferably a hydrogen atom, a halogen atom, or a cyano group, and still more preferably a hydrogen atom or a cyano group. In particular, in the formula (2), B²¹And B²²At least one of which is-C (R)^M1) When is, at least 1R^M1Preferably a halogen atom or a cyano group, more preferably a cyano group. This is because: this further improves atmospheric stability.

In the formula (2), Ch²¹Represents a sulfur atom, a sulfinyl group (-SO-), a sulfonyl group (-SO)₂-), selenium atom, selenoylgroup (-SeO-)₂-, or-B²³-B²⁴-a group represented by (a). B is²³And B²⁴Each independently represents-N ═ or-C (R)^M2)＝。R^M2Represents a hydrogen atom or a substituent. B is²³And B²⁴Are all-C (R)^M2) When not satisfied, B²³R contained in (1)^M2And B²⁴R contained in (1)^M2A ring may be formed. From the viewpoint of further improving atmospheric stability, B is preferable²³And B²⁴Two of (A) are-C (R)^M2) Or one is-N and the other is-C (R)^M2) More preferably, both are-C (R)^M2)＝。B²³And B²⁴Are all-C (R)^M2) When not satisfied, B²³R contained in (1)^M2And B²⁴R contained in (1)^M2A ring may be formed. When a ring is formed, an aromatic heterocyclic ring or an aromatic hydrocarbon ring is preferable, and a benzene ring is more preferable. In addition, B is²³R contained in (1)^M2And B²⁴R contained in (1)^M2When a ring is formed, the ring may have a substituent selected from the above substituent group Z, and the substituents may be bonded to each other to form a further ring. R^M2Represents a hydrogen atom or a substituent. In the formula (2), a plurality of R's are present^M2When a plurality of R^M2Each of which may be the same or different. As useful as R^M2The substituent(s) is not particularly limited, and examples thereof include those selected from the above substituent group Z. From the viewpoint of further improving the carrier mobility, Ch²¹Preferably a sulfur atom, a selenium atom, or-B²³-B²⁴-a group represented by (a).

In the formula (2), X²¹、X²²、X²⁴And X²⁵Each independently represents an oxygen atom or a sulfur atom, but X is preferably X from the viewpoint of further improving atmospheric stability²¹、X²²、X²⁴And X²⁵Are all oxygen atoms.

In the formula (3), A³¹And A³²Are respectively related to A in the formula (2)²¹And A²²Have the same meaning and each independently represents-N (R)^N1)-、-P(R^N1) -or-O-. R^N1Represents a hydrogen atom or a substituent. Plural R^N1Each of which may be the same or different. As R^N1The substituents are not particularly limited, and examples thereof include: a group selected from the above substituent group Z. In addition, regarding A in the formula (3)³¹And A³²The preferred embodiment of (3) is also the same as A in the above formula (2)²¹And A²²The preferred embodiments of the same.

In the formula (3), B³¹And B³²Are respectively matched with B in the formula (2)²¹And B²²Are the same and each independently represents-N ═ or-C (R)^M1)＝。R^M1Represents a hydrogen atom or a substituent. In the formula (3), a plurality of R's are present^M1When a plurality of R^M1Each of which may be the same or different. As R^M1The substituent represented by (a) is not particularly limited, and examples thereof include those selected from the above substituent group Z. In addition, regarding B in the formula (3)³¹And B³²Preferred embodiment of (1)Embodiment, B in the above formula (2) is also the same as B²¹And B²²The preferred embodiments of the same. B is³¹And B³²Are all-C (R)^M1) When not satisfied, B³¹R contained in (1)^M1And B³²R contained in (1)^M1A ring may be formed. The embodiment in this case is also the same as the above formula (2).

In the formula (3), X³¹、X³²、X³⁴And X³⁵Respectively with X in the above formula (2)²¹、X²²、X²⁴And X²⁵Are the same and each independently represents an oxygen atom or a sulfur atom. In addition, X in the formula (3)³¹、X³²、X³⁴And X³⁵The preferred embodiment of (3) is also the same as X in the above formula (2)²¹、X²²、X²⁴And X²⁵The preferred embodiments of the same.

In the formula (3), Ch³¹Represents a sulfur atom, a sulfinyl group (-SO-), a sulfonyl group (-SO)₂-), a selenium atom, a selenoylgroup (-SeO-) or a selenoylgroup (-SeO-)₂-) but is preferably a sulfur atom or a selenium atom from the viewpoint of further improving the carrier mobility.

In the formula (3), R³¹And R³²Each independently represents a hydrogen atom or a substituent. As R³¹And R³²The substituents are not particularly limited, and examples thereof include: a group selected from the above substituent group Z. Of these, R is from the viewpoint of further improving the carrier mobility³¹And R³²Each independently is preferably a hydrogen atom, a cyano group, a halogen atom, a silyl group, or a linear, branched or cyclic alkyl group having 1 to 20 carbon atoms, and more preferably a hydrogen atom, a methyl group, a halogen atom or a cyano group.

The compound represented by the above formula (2) and the compound represented by the above formula (3) can be produced by the production methods described in international publication No. 2011/082234 and international publication No. 2017/022735, and commercially available products can be used.

The compound represented by the above formula (2) or the compound represented by the above formula (3) has a structure in which substituents are introduced to imide nitrogens at both ends of a naphthalene diimide skeleton which is a rigid main chain skeleton, and therefore, has high solubility with respect to the 2, 3-dihydrobenzofuran compound (a), and is less likely to precipitate even in a low-temperature environment.

[ Polymer Compound ]

The ink composition of the present application may contain a polymer compound in addition to the 2, 3-dihydrobenzofuran compound (a) and the solute. The polymer compound is preferably selected from inactive polymers that do not affect the electrical characteristics of the organic semiconductor material, and examples thereof include: specifically, the epoxy resin, the acrylic resin, the polystyrene resin, the cellulose resin, the butyral resin, and the like can be appropriately selected from PMMA (polymethyl methacrylate), PS (polystyrene), PVA (polyvinyl alcohol), PVB (polyvinyl butyral), poly (2,3,4,5, 6-pentafluorostyrene), PVP (polyvinyl phenol), BCB (benzocyclobutene), POSS (caged oligomeric silsesquioxane), PTFEMA (poly (2,2, 2-trifluoroethyl methacrylate)), P2VP (poly (2-vinylpyridine)), and the like.

When an organic semiconductor material having low solubility is used in the edge casting method or the continuous edge casting method described later, the film forming property is improved by, for example, improving the in-plane uniformity of the organic single crystal when the polymer compound is contained. In addition, the influence of the interface of the insulating film may be minimized, and high performance may be exhibited on any surface of the insulating film. The film forming property described in the present specification means a set value of an ink composition temperature, a substrate temperature, a coating speed (single crystal growth speed), a slit temperature, a piping temperature, an ink tank temperature, a distance between a slit and a substrate, and the like in organic single crystal film formation, and means a degree that the film forming property is good to enable film formation at low temperatures and high speeds, respectively.

When the ink composition of the present invention contains the polymer compound, the content thereof is not particularly limited, and is preferably 0.01 to 20% by weight, more preferably 0.1 to 10% by weight, based on 100% by weight of the ink composition. When the content of the polymer compound is within this range, the film forming property of the ink composition of the present invention tends to be improved.

The ink composition of the present application contains the above-mentioned 2, 3-dihydrobenzofuran compound (a) as a solvent, a solute (particularly an organic semiconductor material), and the above-mentioned polymer compound as necessary. The 2, 3-dihydrobenzofuran compound (a), the solute, and the polymer compound to be compounded as required may be used singly or in combination of two or more.

The ink composition of the present application can be prepared, for example, as follows: mixing the 2, 3-dihydrobenzofuran compound (A), a solute, and a polymer compound which is compounded as required, and heating the mixture at a temperature of about 30 to 100 ℃ for about 0.1 to 5 hours in an air atmosphere, a nitrogen atmosphere, or an argon atmosphere.

The content of the 2, 3-dihydrobenzofuran compound (a) in the total amount of the ink composition of the present application (in the case of containing two or more species, the total amount thereof) is, for example, 99.999% by weight or less. The lower limit is, for example, 90.000 wt%, preferably 93.000 wt%, particularly 95.000 wt%, and the upper limit is preferably 99.990 wt%.

For example, the content (total amount in the case of containing two or more species) of the solute (particularly, the organic semiconductor material) in the ink composition of the present application is, for example, 0.02 parts by weight or more, preferably 0.03 parts by weight or more, and particularly preferably 0.04 parts by weight or more, relative to 100 parts by weight of the 2, 3-dihydrobenzofuran compound (a). The upper limit of the content of the solute is, for example, 1 part by weight, preferably 0.5 part by weight, and particularly preferably 0.1 part by weight.

The weight ratio of the solute (particularly, the organic semiconductor material) to the polymer compound (solute/polymer compound) in the ink composition of the present application is, for example, 0.01 or more, preferably 0.02 or more, and particularly preferably 0.1 or more. The upper limit of the weight ratio is, for example, 1000, preferably 500, more preferably 100, still more preferably 50, and particularly preferably 10.

< organic thin film transistor >

Next, the structure of an organic thin film transistor provided with an organic single crystal semiconductor using the ink composition for manufacturing an organic semiconductor device of the present invention and a method for manufacturing an organic thin film transistor including a step of forming an organic single crystal semiconductor film by applying the ink composition for manufacturing an organic semiconductor device of the present invention onto a substrate will be described with reference to fig. 1 and 2.

Fig. 1 is a schematic diagram showing a cross-sectional structure of an example of an organic thin film transistor. The organic thin film transistor is formed on a temporary fixing substrate 100 (also referred to as a carrier) for processing in the process, including: a flexible resin substrate 101, a conductive thin film (gate electrode) 102, a gate insulating film 103, an organic single crystal semiconductor thin film 104, a conductive thin film (source electrode, drain electrode) 105, a charge injection layer 106 for ohmic contact, and a protective layer 107. Hereinafter, the fabrication of the organic thin film transistor will be briefly described.

First, the conductive thin film 102 is formed on the resin substrate 101 temporarily fixed to the temporary fixing substrate 100 for processing, and a gate electrode of the organic thin film transistor is formed.

Examples of the method for forming the conductive thin film 102 include: sputtering; a PVD method typified by a vacuum evaporation method; or a method in which the conductive thin film 102 is formed on the resin substrate 101 by an application method using an ink containing a conductive material, and then patterned into a predetermined shape by photolithography.

Other methods for forming the conductive thin film 102 include, for example: a method of directly forming the conductive thin film 102 patterned into a predetermined shape on the resin substrate 101 by a plate printing method or a plateless printing method. By directly forming the conductive thin film 102 patterned into a predetermined shape, the process can be simplified.

The conductive thin film 102 may be formed by a plating method. Examples of the method for forming the conductive thin film 102 by the plating method include: a method of forming a plating primer layer patterned into a predetermined shape on the resin substrate 101 in advance by a photolithography method, a plate printing method, or a plateless printing method, and forming the conductive thin film 102 at a predetermined position by an electroless plating method, or a combination of the electroless plating method and the electroplating method.

The thickness of the conductive thin film 102 is not particularly limited, but is preferably 20nm to 1 μm, and more preferably 20nm to 300 nm.

Next, the gate insulating film 103 is formed on the resin substrate 101 and the conductive thin film 102. The gate insulating film 103 is preferably an organic insulating film containing a ferroelectric or polymer compound such as ceramic typified by a metal compound having a high relative dielectric constant. The thickness of the gate insulating film 103 is not particularly limited, but is preferably 1nm to 1 μm, more preferably 10nm to 600nm, and still more preferably 10nm to 200 nm.

Next, an organic single crystal semiconductor film 104' unpatterned to a shape of a transistor is formed over the gate insulating film 103 by a drop casting method, an ink jet printing method, an edge casting method, or a continuous edge casting method using the ink composition of the present application. The edge casting method and the continuous edge casting method can be carried out by a known method (for example, the method described in japanese patent laid-open publication No. 2015-185620).

Fig. 2 is a conceptual diagram illustrating an example of a method for forming an organic single crystal semiconductor film by a continuous edge casting method. To briefly explain fig. 2, the present invention includes, at minimum: after a substrate stage 200 on which a substrate is placed on a continuous edge casting apparatus, a slit 201 for continuous edge casting coating/ink supply, and an ink tank 202 are set, the ink tank 202 is pressurized to supply ink to the substrate surface, thereby forming a meniscus 203 of the ink, and then all parameters such as a coating rate (single crystal growth rate), heating of each part of the apparatus, heating of the substrate, and an evaporation rate are finely adjusted, thereby obtaining an organic single crystal semiconductor film 104'. The drop casting method and the inkjet printing method may be performed by a known method.

Then, with respect to the organic single crystal semiconductor film 104' which is formed by a drop casting method, an ink jet printing method, an edge casting method, or a continuous edge casting method and is not patterned into a transistor shape, a given shape is patterned by a photolithography method, thereby forming the organic single crystal semiconductor thin film 104.

After the organic single crystal semiconductor thin film 104 is formed, a firing process for controlling the form and volatilizing the solvent contained in the organic single crystal semiconductor thin film 104 is performed. The thickness of the organic single-crystal semiconductor thin film 104 is not particularly limited, but is preferably 1nm to 1000nm, more preferably 1nm to 100nm, and still more preferably 1nm to 50 nm.

The most preferable film is not a thick film but a crystalline film having 3 to 6 molecular layers or less, and the most preferable total number of molecules varies depending on the molecular structure.

Next, a patterned conductive thin film 105 is formed over the gate insulating film 103 and the organic single crystal semiconductor thin film 104. The conductive thin film 105 forms a source electrode and a drain electrode of the organic thin film transistor.

The conductive thin film 105 can be formed by the same method as that for the conductive thin film 102 described above. The conductive thin film 105 may be formed by the same method as that for forming the conductive thin film 102, or may be formed by a different method. Further, if necessary, a charge injection layer 106 for ohmic-bonding the organic single crystal semiconductor thin film 104 and the conductive thin film 105 may be provided between the organic single crystal semiconductor thin film 104 and the conductive thin film 105.

The thickness of the conductive thin film 105 (i.e., the thickness of the source electrode and the drain electrode of the organic thin film transistor) is not particularly limited, but is preferably 20nm to 1 μm, more preferably 20nm to 600nm, and still more preferably 20nm to 500 nm.

Next, a protective layer 107 is formed on the gate insulating film 103, the organic single-crystal semiconductor thin film 104, and the conductive thin film 105. Examples of the method for forming the protective layer 107 include: a PVD method typified by a vacuum evaporation method; a CVD method typified by an ALD (atomic layer deposition) method; a method in which the protective layer 107 is formed by a coating method using an ink containing a protective layer material, and then patterned into a predetermined shape by photolithography.

In addition, as another method for forming the protective layer 107, for example: a method of directly forming the protective layer 107 patterned into a predetermined shape by a plate printing method or a plateless printing method. By directly forming the protective layer 107 patterned into a predetermined shape, the process of forming the protective layer 107 can be simplified.

Of these, a method of directly forming the protective layer 107 patterned into a predetermined shape by a plate printing method or a plateless printing method is preferable. Further, as another method, patterning can be performed by laser ablation for a given hole.

When the protective layer 107 patterned into a predetermined shape is directly formed by a plate printing method or a plateless printing method, inks containing various protective layer materials can be used. Examples of the ink containing a protective layer material include a dispersion ink containing an inorganic material, an ink containing an SOG (spin on glass) material and a low-molecular protective layer material, and an ink containing a high-molecular protective layer material, and preferably an ink containing a high-molecular protective layer material.

As a material for forming the protective film 107, materials similar to those exemplified for the gate insulating film 103 can be used, except for the materials contained in the ink and the SOG material.

The thickness of the protective layer 107 is not particularly limited, but is preferably 50nm to 5.0. mu.m, more preferably 500nm to 3.0. mu.m.

Finally, the flexible resin substrate 101 is peeled off from the temporary fixing substrate 100, thereby completing the organic thin film transistor on the flexible substrate. As a method of peeling the flexible resin substrate 101, a laser lift-off method (LLO) can be used. Alternatively, a release layer or a micro adhesive layer may be formed in advance between the temporary fixing substrate 100 and the flexible resin substrate 101 using a fluorine-based polymer, a self-assembled monolayer (SAMs), a micro adhesive agent, or the like, and after completion, they may be physically separated. Of course, when the release layer or the micro adhesive layer is formed, the layer may be finally peeled off by LLO. Thus, an organic thin film transistor can be manufactured.

The ink composition of the present invention uses the 2, 3-dihydrobenzofuran compound (a) as a solvent, and thus can dissolve a solute (particularly, an organic semiconductor material) at a high concentration even at a relatively low temperature (for example, 20 to 50 ℃, preferably 20 to 40 ℃). In addition, since the ink composition has appropriate volatility suitable for a printing process in the temperature environment and the concentration of the ink composition can be kept constant, high film forming properties and high printability can be exhibited. Therefore, even in a low-temperature environment, the organic semiconductor device can be easily formed by a simple method based on the wet process such as the edge casting method and the continuous edge casting method, and the cost can be greatly reduced.

Further, although the organic semiconductor device has low heat resistance as compared with a glass substrate, it has high impact resistance, and can be directly formed on a lightweight and flexible plastic substrate, thereby forming a lightweight and flexible display or computer device having high impact resistance. Further, if the ink composition of the present application is applied on a substrate, the solute (n-type organic semiconductor material) contained in the composition is crystallized by self-assembly action, and an organic semiconductor device (e.g., organic thin film transistor) having high carrier mobility is obtained.

The transistor characteristics of the organic thin film transistor manufactured by the method of the present application can be measured based on, for example, the following carrier mobility.

(evaluation of Carrier mobility)

For the evaluation of the carrier mobility, for example, the following test conditions 1 or 2 can be used.

Test conditions 1: a voltage of +50V was applied between the source electrode and the drain electrode of the organic thin film transistor at 1 atm (temperature: room temperature) using a semiconductor parameter analyzer (4200-SCS, manufactured by KEITHLEY Co., Ltd.) so that the gate voltage was varied within a range of-20V to +50V, and the drain current I was expressed_dThe carrier mobility μ (cm) was calculated by the following equation²/Vs)。

Test conditions 2: a voltage of +40V was applied between the source electrode and the drain electrode of the organic thin film transistor at 1 atm (temperature: room temperature) using a semiconductor parameter analyzer (4200-SCS, manufactured by KEITHLEY Co., Ltd.) so that the gate voltage was varied within a range of-20V to +40V, and the drain current I was expressed_dThe carrier mobility μ (cm) was calculated by the following equation²/Vs)。

I_d＝(w/2L)μC_i(V_g－V_th)²

In the formula, LDenotes the gate length, w denotes the gate width, μ denotes the carrier mobility, C_iDenotes the capacity per unit area, V, of the gate insulating film_gDenotes the gate voltage, V_thWhich is indicative of the threshold voltage of the transistor,

the higher the carrier mobility μ of the organic thin film transistor manufactured by the method of the present application is, the more preferable, for example, 0.1cm²A value of more than Vs, preferably 0.3cm²More preferably 0.5 cm/Vs or more²More preferably 0.7 cm/Vs or more²A value of more than Vs, particularly preferably 1.0cm²Over Vs.

The organic thin film transistor can be used for, for example, electronic paper, a display device, a sensor, an electronic tag, and the like without any particular limitation.

The embodiments and combinations thereof described above are merely examples, and additions, omissions, substitutions, and other modifications of the embodiments can be made as appropriate without departing from the scope of the invention of the present application. The invention of the present application is not limited to the embodiments, but is limited only by the scope of the claims.

The various embodiments disclosed in this specification may also be combined with any other features disclosed in this specification.

Examples

The invention of the present application will be described in more detail with reference to examples below, but the invention of the present application is not limited to these examples.

Example 1: 2, 9-bis [ (1S) -1-methylpentyl ] -1,2,3,8,9, 10-hexahydro-1, 3,8, 10-tetraoxaanthraco [2,1,9-def:6,5,10-d ' e ' f ' ] diisoquinoline-5, 12-dinitrile (the compound represented by the above (1-5), hereinafter referred to as compound (1-5)) as a solute was mixed in a solvent 2, 3-dihydrobenzofuran (made of Dacellosolve, Ltd.) so as to be 0.05% by weight, and the mixture was dissolved by heating at 80 ℃ for 3 hours to obtain a solution of the ink composition for producing an organic semiconductor device.

The obtained solution was applied to a fluorine-based resin substrate by a continuous edge casting method shown in fig. 2 to produce a single crystal film. On 25 sites of the prepared single crystal film are preparedAn organic thin film transistor as shown in fig. 1. The transistor characteristics of the obtained organic thin film transistor were measured under test condition 1 for the evaluation of the carrier mobility. The average value of 25 parts is used to obtain the carrier mobility of 0.66cm²Performance of/Vs.

Example 2: a compound (1-5) as a solute was mixed in an amount of 0.1 wt% in a solvent 2, 3-dihydrobenzofuran (made of cellosolve, Ltd.), and poly-alpha-methylstyrene as an additive was mixed in an amount of 0.04 wt%, and the mixture was dissolved by heating at 80 ℃ for 3 hours to obtain a solution of an ink composition for manufacturing an organic semiconductor device. The weight ratio (solute/polymer compound) of the solute (compound (1-5)) to the polymer compound (poly α methylstyrene) was 2.5. The obtained solution was applied to a parylene-coated resin substrate by a continuous edge casting method shown in fig. 2 to produce a single crystal film. The organic thin film transistor shown in fig. 1 was fabricated at 25 sites on the fabricated single crystal film. The transistor characteristics of the obtained organic thin film transistor were measured under test condition 1 for the evaluation of the carrier mobility. The carrier mobility was found to be 0.32cm in an average of 19 sites²Performance of/Vs.

Example 3: a compound (1-5) as a solute was mixed in an amount of 0.1 wt% in a solvent 2, 3-dihydrobenzofuran (made of cellosolve, Ltd.), and poly-alpha-methylstyrene as an additive was mixed in an amount of 0.04 wt%, and the mixture was dissolved by heating at 80 ℃ for 3 hours to obtain a solution of an ink composition for manufacturing an organic semiconductor device. The weight ratio (solute/polymer compound) of the solute (compound (1-5)) to the polymer compound (poly α methylstyrene) was 2.5. The resulting solution was used to form a self-assembled monolayer on a resin substrate. Further, the self-assembled monolayer was coated by a continuous edge casting method shown in fig. 2, thereby producing a single crystal film. The organic thin film transistor shown in fig. 1 was fabricated at 5 sites on the fabricated single crystal film. The transistor characteristics of the obtained organic thin film transistor were measured under test condition 2 for the evaluation of the carrier mobility. The average value of 5 sites was used to obtain carriersMobility 0.76cm²Performance of/Vs.

As a summary of the above, the structure and its modifications of the present invention will be described below.

[1] An ink composition comprising: a solvent selected from at least one of the 2, 3-dihydrobenzofuran compounds (A) represented by the formula (a), and at least one solute.

[2] The ink composition according to [1], wherein,

r in the formula (a)¹、R²、R³、R⁴、R⁵And R⁶Each is a hydrogen atom, a halogen atom, or C optionally having a substituent selected from the above group 1_1-20An alkyl group.

[3] The ink composition according to [2], wherein,

the halogen atom is a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom.

[4] The ink composition according to [2] or [3], wherein,

c above_1-20The alkyl group is a linear or branched alkyl group having 1 to 20 carbon atoms.

[5] The ink composition according to [1], wherein,

the 2, 3-dihydrobenzofuran compound (A) is 2, 3-dihydrobenzofuran and/or 2, 3-dihydro-2-methylbenzofuran.

[6] The ink composition according to [1], wherein,

the above-mentioned 2, 3-dihydrobenzofuran compound (A) is 2, 3-dihydrobenzofuran.

[7] The ink composition according to any one of [1] to [6], wherein,

the proportion of the 2, 3-dihydrobenzofuran compound (a) in the total solvent is 90% by weight or more (preferably 93% by weight or more, more preferably 95% by weight or more, and still more preferably 100% by weight).

[8] The ink composition according to any one of [1] to [7], wherein,

the purity of the 2, 3-dihydrobenzofuran compound (a) is 98.0% or more (preferably 98.5% or more, more preferably 99.0% or more, still more preferably 99.5% or more, and particularly preferably 99.9% or more).

[9] The ink composition according to any one of [1] to [8], wherein,

the water content of the solvent is 0.25 wt% or less (preferably 0.19 wt% or less, more preferably 0.05 wt% or less).

[10] The ink composition according to any one of [1] to [9], wherein,

the solute is an n-type organic semiconductor material.

[11] The ink composition according to [10], wherein,

the n-type organic semiconductor material is a compound represented by formula (1).

[12] The ink composition according to [11], wherein,

a in the formula (1)¹¹And A¹²Are all-N (R)^N)-。

[13] The ink composition according to [12], wherein,

r is as defined above^NIs an alkyl group having 4 to 20 carbon atoms which may have a substituent.

[14] The ink composition according to [13], wherein,

the above-mentioned substituent is an unsubstituted alkyl group, a halogenated alkyl group or an aryl group.

[15] The ink composition according to any one of [11] to [14], wherein,

b in the formula (1)¹¹～B¹⁸is-N or-C (R)^M)-。

[16] The ink composition according to any one of [11] to [15], wherein,

x in the formula (1)¹¹～X¹⁴Is an oxygen atom.

[17] The ink composition according to any one of [11] to [14], wherein,

x in the formula (1)¹¹～X¹⁴Is an oxygen atom, B¹¹～B¹⁸is-C (R)^M)-。

[18] The ink composition according to any one of [15] to [17], wherein,

r is as defined above^MIs hydrogen atom, alkyl group, allyl group, heteroaryl group, halogen group or cyano group.

[19] The ink composition according to [11], wherein,

the compound represented by the formula (1) is at least one compound selected from the compounds represented by the formulae (1-1) to (1-5).

[20] The ink composition according to [11], wherein,

the compound represented by the formula (1) is a compound represented by the formula (1-5).

[21] The ink composition according to [10], wherein,

the n-type organic semiconductor material is a compound represented by formula (2).

[22] The ink composition according to [21], wherein,

a in the formula (2)²¹And A²²Are all-N (R)^N1)-。

[23] The ink composition according to [22], wherein,

r is as defined above^N1Is cyclohexyl.

[24] The ink composition according to any one of [21] to [23], wherein,

b in the formula (2)²¹And B²²is-C (R)^M1)＝。

[25] The ink composition according to [24], wherein,

r is as defined above^M1Is a halogen atom or a cyano group, and one or both of them are cyano groups.

[26] The ink composition according to any one of [21] to [25], wherein,

ch in the formula (2)²¹is-B²³-B²⁴-。

[27] The ink composition according to [26], wherein,

b above²³And B²⁴is-C (R)^M2)＝。

[28] The ink composition according to [27], wherein,

r is as defined above^M2Is a halogen atom or a cyano group.

[29] The ink composition according to any one of [21] to [28], wherein,

x in the formula (2)²¹、X²²、X²⁴And X²⁵Is an oxygen atom.

[30] The ink composition according to [10], wherein,

the n-type organic semiconductor material is a compound represented by formula (3).

[31] The ink composition according to [30], wherein,

a in the formula (3)³¹And A³²Are all-N (R)^N1)-。

[32] The ink composition according to [31], wherein,

r is as defined above^N1Is cyclohexyl.

[33] The ink composition according to any one of [30] to [32], wherein,

b in the formula (3)³¹And B³²is-C (R)^M1)＝。

[34] The ink composition according to [33], wherein,

r is as defined above^M1Is a halogen atom or a cyano group, and one or both of them are cyano groups.

[35] The ink composition according to any one of [30] to [34], wherein,

x in the formula (3)³¹、X³²、X³⁴And X³⁵Is an oxygen atom.

[36] The ink composition according to any one of [30] to [35], wherein,

ch in the formula (3)³¹Is a sulfur atom or a selenium atom.

[37] The ink composition according to any one of [30] to [36], wherein,

r in the formula (3)³¹And X³²Is a hydrogen atom, a methyl group, a halogen atom or a cyano group.

[38] The ink composition according to any one of [1] to [37], wherein,

the solute further contains a polymer compound as the component 2.

[39] The ink composition according to [38], wherein,

the polymer compound is polystyrene resin.

[40] The ink composition according to [39], wherein,

the polystyrene resin is poly-alpha-methylstyrene.

[41] The ink composition according to any one of [1] to [40], which is used for producing an organic single-crystal semiconductor film by a drop casting method, an ink-jet printing method, an edge casting method, or a continuous edge casting method.

[42] The ink composition according to any one of [1] to [40], which is used for producing an organic single-crystal semiconductor film by a continuous edge casting method.

[43] A method for producing an organic single crystal semiconductor film, which method uses the ink composition according to any one of [1] to [42 ].

[44] The production method according to [43], wherein,

the film thickness of the organic single crystal semiconductor film is 1nm to 100 nm.

[45] The production method according to [43], wherein,

the organic single crystal semiconductor film is a crystalline film having a layer of 6 molecules or less.

[46] Use of the ink composition according to any one of the above [1] to [42] as an ink for manufacturing an organic semiconductor device.

[47] A method of making an ink composition, the method comprising:

the ink composition according to any one of [1] to [42] is produced by mixing at least a 2, 3-dihydrobenzofuran compound (A) with a solute and heating at 30 to 100 ℃ for about 0.1 to 5 hours.

[48] A method for producing an ink for producing an organic semiconductor device, wherein the ink for producing an organic semiconductor device is the ink composition according to [42 ].

Industrial applicability

By using the ink composition for manufacturing an organic semiconductor device of the present application to manufacture an n-type organic single crystal transistor, a high-performance organic thin film transistor can be efficiently obtained at low cost. In particular, by combining the drop casting method, the ink-jet printing method, the edge casting method, and the continuous edge casting method, the properties of the n-type organic semiconductor material can be exhibited to the maximum extent.