JP2022130386A - ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink composition that is excellent in charge transportability and can be applied to various wet processes in formation of a charge-transporting film in an organic electroluminescent element.

SOLUTION: An ink composition comprises (A) polythiophene, (B) an onium borate salt comprising two kinds of aryl groups represented by a general formula, and (C) an organic solvent.

SELECTED DRAWING: None

COPYRIGHT: (C)2022,JPO&INPIT

Description

The present invention relates to ink compositions comprising a polythiophene compound, an onium borate salt and a liquid carrier. The present disclosure also relates to a charge-transporting thin film formed from the ink composition, and an organic electroluminescence device having the charge-transporting thin film.

A charge-transporting thin film made of an organic compound is used as a light emitting layer or a charge injection layer in an organic electroluminescence (hereinafter referred to as organic EL) device. In particular, the hole-injecting layer is responsible for transferring charges between the anode and the hole-transporting layer or the light-emitting layer, and plays an important role in achieving low-voltage driving and high luminance of the organic EL device.
The method of forming the hole injection layer is broadly divided into a dry process represented by vapor deposition and a wet process represented by spin coating. It is possible to efficiently manufacture a thin film with high toughness. Therefore, as organic EL displays are becoming larger in area, there is a demand for a hole injection layer that can be formed by a wet process.
In view of such circumstances, the present inventors have found that a thin film having charge transport properties that can be applied to various wet processes and that can realize excellent EL device characteristics when applied to the hole injection layer of an organic EL device. Materials and compounds with good solubility in organic solvents used for them have been developed (Patent Documents 1 and 2).

On the other hand, as an ink composition for organic electronic devices, a composition containing a sulfonated conjugated polymer, an amine compound, etc. is known (Patent Document 3). The presence of an amine compound in the ink composition not only provides the ink composition with good shelf life and stability, but the thin films formed from the ink composition exhibit excellent homogeneity. However, the charge transport properties of organic light emitting diode (OLED) devices containing hole injection layers formed from the ink compositions still need improvement.

WO2008/032616 WO2008/129947 WO2016/171935

The problem to be solved by the present invention is to provide an ink composition that is applicable to various wet processes and has excellent charge transport properties.

As a result of intensive research, the present inventors have found that an ink composition containing a polythiophene compound having a specific structure, an onium borate salt having a specific structure, and a liquid carrier can be applied to various wet processes and has good charge transport properties. The inventors have found that an excellent charge-transporting thin film can be formed, and completed the present invention.

That is, the present invention provides the following inventions.

［式中、Ｒ_１及びＲ_２は、それぞれ独立に、Ｈ、アルキル、フルオロアルキル、アルコキシ、フルオロアルコキシ、アリールオキシ、－ＳＯ_３Ｍ、又は－Ｏ－［Ｚ－Ｏ］_ｐ－Ｒ_ｅであるか、あるいは、Ｒ_１及びＲ_２は、一緒になって－Ｏ－Ｚ－Ｏ－を形成する
（式中、Ｍは、Ｈ、アルカリ金属、アンモニウム、モノアルキルアンモニウム、ジアルキルアンモニウム、又はトリアルキルアンモニウムであり、Ｚは、場合によりハロゲン又はＹで置換されているヒドロカルビレン基（ここで、Ｙは、炭素数１～１０の直鎖又は分岐鎖のアルキル基又はアルコキシアルキル基であり、該アルキル基又はアルコキシアルキル基は、任意の位置がスルホン酸基で置換されていてもよい）であり、ｐは、１以上の整数であり、そして、Ｒ_ｅは、Ｈ、アルキル、フルオロアルキル、又はアリールである）］で表される繰り返し単位を含むポリチオフェン；
（Ｂ）オニウムボレート塩であって、式（ａ１）：

で表されるアニオン、及び式（ａ２）：

で表される１価又は２価のアニオン
［式中、Ａｒは、それぞれ独立して、置換基を有してもよいアリール基又は置換基を有してもよいヘテロアリール基であり、Ｒは、炭素数１～１０のアルキル基、炭素数３～２０のシクロアルキル基、炭素数１～１０のフルオロアルキル基、炭素数７～１０のアラルキル基又は炭素数７～１０のフルオロアラルキル基であり、Ｌは、アルキレン基、－ＮＨ－、酸素原子、硫黄原子又は－ＣＮ⁺－である］からなる群より選択される少なくとも１種のアニオンと対カチオンとからなるオニウムボレート塩（ただし、電気的中性な塩である）；及び
（Ｃ）有機溶媒を含む液体担体
を含む組成物。 (1) An ink composition comprising
(A) Formula (I):

[wherein R ₁ and R ₂ are each independently H, alkyl, fluoroalkyl, alkoxy, fluoroalkoxy, aryloxy, -SO ₃ M, or -O-[ZO] _p -R _e Alternatively, R ₁ and R ₂ together form —O—ZO—, where M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium and Z is a hydrocarbylene group optionally substituted with halogen or Y (wherein Y is a linear or branched alkyl or alkoxyalkyl group having 1 to 10 carbon atoms, the alkyl or an alkoxyalkyl group may be substituted with a sulfonic acid group at any position), p is an integer greater than or equal to 1, and R _e is H, alkyl, fluoroalkyl, or aryl is)] polythiophene containing a repeating unit represented by;
(B) an onium borate salt of formula (a1):

and an anion of formula (a2):

A monovalent or divalent anion represented by [wherein Ar is each independently an optionally substituted aryl group or optionally substituted heteroaryl group, and R is , an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or a fluoroaralkyl group having 7 to 10 carbon atoms. , L is an alkylene group, —NH—, an oxygen atom, a sulfur atom, or —CN ⁺ —. and (C) a liquid carrier comprising an organic solvent.

(2) The ink composition according to (1), wherein Ar is an aryl group having one or more electron-withdrawing substituents.

(3) The ink composition according to (2), wherein the electron-withdrawing substituent is a halogen atom.

(4) The ink composition according to any one of (1) to (3), wherein the anion is represented by formula (a3).

からなる群より選択される、（１）～（４）のいずれか一つに記載のインク組成物。 (5) the counter cation is represented by formulas (c1) to (c5):

The ink composition according to any one of (1) to (4), which is selected from the group consisting of:

(6) The ink composition according to any one of (1) to (5), wherein component (B) is represented by the following formula.

(7) R ₁ and R ₂ are each independently H, fluoroalkyl, -SO ₃ M, -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e , or -OR _f , or R ₁ and R ₂ together are -O-(CH ₂ ) _q -O-, where (CH ₂ ) _q is optionally substituted with Y wherein M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium, and each R _a , R _b , R _c , and R _d is independently H, halogen, alkyl, fluoroalkyl, or aryl; R _e is H, alkyl, _fluoroalkyl , or aryl; p is 1, 2, or 3; , fluoroalkyl, or aryl; q is 1, 2, or 3; and Y is a linear or branched alkoxyalkyl group having 1 to 10 carbon atoms, the alkoxyalkyl group being any The ink composition according to any one of (1) to (6), which is optionally substituted with a sulfonic acid group.

(8) The ink composition according to any one of (1) to (7), wherein R ₁ is H and R ₂ is other than H.

(9) The ink composition according to any one of (1) to (7), wherein both R ₁ and R ₂ are other than H.

(10) R ₁ and R ₂ are each independently -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e or -OR _f , or The ink composition according to (9), wherein R ₁ and R ₂ together form —O—(CH ₂ ) _q —O—.

(11) The ink composition according to (9), wherein both R ₁ and R ₂ are -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e .

(12) each R _a , R _b , R _c , and R _d is each independently H, (C ₁ -C ₈ )alkyl, (C ₁ -C ₈ )fluoroalkyl, or phenyl; and The ink composition according to any one of (7) to (11), wherein R _e is (C ₁ -C ₈ )alkyl, (C ₁ -C ₈ )fluoroalkyl, or phenyl.

で表される基（式中、Ｍは、Ｈ、アルカリ金属、アンモニウム、モノアルキルアンモニウム、ジアルキルアンモニウム、又はトリアルキルアンモニウムである）、及びこれらの組合せからなる群より選択される繰り返し単位を含む、（１）～（１２）のいずれか一つに記載のインク組成物。 (13) Component (A) has the following formula:

wherein M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium), and a repeating unit selected from the group consisting of combinations thereof; The ink composition according to any one of (1) to (12).

(14) The ink composition according to any one of (1) to (13), wherein component (A) is sulfonated poly(3-MEET).

(15) Any one of (1) to (14), wherein component (A) contains repeating units represented by formula (I) in an amount greater than 50% by weight based on the total weight of repeating units. The ink composition according to .

(16) The ink according to any one of (1) to (15), wherein component (C) contains at least one selected from the group consisting of glycol monoethers, glycol diethers and glycols. Composition.

(17) The ink composition according to any one of (1) to (16), further comprising (D) an amine compound.

(18) The ink composition according to (17), wherein the component (D) comprises (D1) a tertiary alkylamine compound and (D2) an amine compound other than the tertiary alkylamine compound.

(19) The ink composition according to (18), wherein the component (D2) is a primary alkylamine compound.

(20) The primary alkylamine compound is at least one selected from the group consisting of ethylamine, n-butylamine, t-butylamine, 2-ethylhexylamine, n-hexylamine, n-decylamine and ethylenediamine, ( 19) The ink composition described above.

(21) The ink composition according to (19) or (20), wherein the primary alkylamine compound is n-butylamine.

(22) The ink composition according to any one of (1) to (21), further comprising (E) metal oxide nanoparticles.

(23) The ink composition according to any one of (1) to (22), further comprising (F) a matrix compound.

(24) A charge-transporting thin film formed from the ink composition according to any one of (1) to (23).

(25) An organic electroluminescence device having the charge-transporting thin film according to (24).

(26) A method for producing a charge-transporting thin film, which comprises applying the ink composition according to any one of (1) to (23) onto a substrate and evaporating the solvent.

［式中、Ｒ_１及びＲ_２は、それぞれ独立に、Ｈ、アルキル、フルオロアルキル、アルコキシ、フルオロアルコキシ、アリールオキシ、－ＳＯ_３Ｍ、又は－Ｏ－［Ｚ－Ｏ］_ｐ－Ｒ_ｅであるか、あるいは、Ｒ_１及びＲ_２は、一緒になって－Ｏ－Ｚ－Ｏ－を形成する
（式中、Ｍは、Ｈ、アルカリ金属、アンモニウム、モノアルキルアンモニウム、ジアルキルアンモニウム、又はトリアルキルアンモニウムであり、Ｚは、場合によりハロゲン又はＹで置換されているヒドロカルビレン基（ここで、Ｙは、炭素数１～１０の直鎖又は分岐鎖のアルキル基又はアルコキシアルキル基であり、該アルキル基又はアルコキシアルキル基は、任意の位置がスルホン酸基で置換されていてもよい）であり、ｐは、１以上の整数であり、そして、Ｒ_ｅは、Ｈ、アルキル、フルオロアルキル、又はアリールである）］で表される繰り返し単位を含むポリチオフェン；
（Ｂ）オニウムボレート塩であって、式（ａ１）：

で表されるアニオン、式（ａ２）：

で表される１価又は２価のアニオン、及び（ａ５）

で表されるアニオン
［式中、Ａｒは、それぞれ独立して、置換基を有してもよいアリール基又は置換基を有してもよいヘテロアリール基であり、Ｒは、炭素数１～１０のアルキル基、炭素数３～２０のシクロアルキル基、炭素数１～１０のフルオロアルキル基、炭素数７～１０のアラルキル基又は炭素数７～１０のフルオロアラルキル基であり、Ｌは、アルキレン基、－ＮＨ－、酸素原子、硫黄原子又は－ＣＮ⁺－であり、Ｅは長周期型周期表の第１３族又は第１５族に属する元素を表す］からなる群より選択される少なくとも１種のアニオンと対カチオンとからなるオニウムボレート塩（ただし、電気的中性な塩である）；
（Ｃ）有機溶媒を含む液体担体；及び
（Ｆ）マトリックス化合物
を含む組成物。 (27) An ink composition comprising:
(A) Formula (I):

[wherein R ₁ and R ₂ are each independently H, alkyl, fluoroalkyl, alkoxy, fluoroalkoxy, aryloxy, -SO ₃ M, or -O-[ZO] _p -R _e Alternatively, R ₁ and R ₂ together form —O—ZO—, where M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium and Z is a hydrocarbylene group optionally substituted with halogen or Y (where Y is a linear or branched alkyl or alkoxyalkyl group having 1 to 10 carbon atoms, and the alkyl or an alkoxyalkyl group may be substituted with a sulfonic acid group at any position), p is an integer greater than or equal to 1, and R _e is H, alkyl, fluoroalkyl, or aryl is)] polythiophene containing a repeating unit represented by;
(B) an onium borate salt of formula (a1):

An anion of the formula (a2):

A monovalent or divalent anion represented by and (a5)

[Wherein Ar is each independently an optionally substituted aryl group or optionally substituted heteroaryl group, R has 1 to 10 carbon atoms an alkyl group, a cycloalkyl group having 3 to 20 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms or a fluoroaralkyl group having 7 to 10 carbon atoms, and L is an alkylene group , -NH-, an oxygen atom, a sulfur atom or -CN ⁺ -, and E represents an element belonging to Group 13 or Group 15 of the long period periodic table]. An onium borate salt consisting of an anion and a countercation (provided that it is an electrically neutral salt);
(C) a liquid carrier comprising an organic solvent; and (F) a composition comprising a matrix compound.

INDUSTRIAL APPLICABILITY According to the present invention, it is possible to provide an ink composition that is applicable to various wet processes and has excellent charge transport properties.

FIG. 1 shows cross-sectional shapes of the charge-transporting thin films of Example 3 and Comparative Example 2. FIG.

As used herein, nouns written in the singular or indiscriminately in the singular or plural are defined as “one (one) or more” or “at least one (one)” unless otherwise specified. individual)”.

As used herein, the term "comprises" includes "consisting essentially of" and "consisting of." The term "comprising" encompasses "consisting essentially of" and "consisting of".

The phrase "free of" means the absence of external additions of materials modified by this phrase and analytical techniques known to those skilled in the art (e.g., gas or liquid chromatography, spectrophotometry, optical It means that there is no detectable amount of this material observable by microscopy, etc.).

Throughout this disclosure, various publications are incorporated by reference. If the meaning of any language in that publication incorporated herein by reference conflicts with the meaning of language in the disclosure, the meaning of language in the disclosure controls unless otherwise stated.

As used herein, the term "(C _x -C _y )" (where x and y are each integers) in reference to an organic group means that the group contains carbon atoms in one group It means that it may contain from x to y carbon atoms.

As used herein, the term “alkyl” refers to a monovalent straight or branched chain saturated hydrocarbon group, more typically a monovalent straight or branched saturated (C ₁ -C ₄₀ ) hydrocarbon groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, tert-butyl, hexyl, 2-ethylhexyl, octyl, hexadecyl, octadecyl, eicosyl, behenyl, triacontyl, and tetracontyl, etc. do.

As used herein, the term "fluoroalkyl" refers to an alkyl group as defined herein, substituted with one or more fluorine atoms, more typically (C ₁ -C ₄₀ ) means an alkyl group. Examples of fluoroalkyl groups include, eg, difluoromethyl, trifluoromethyl _, perfluoroalkyl, 1H,1H,2H,2H _- perfluorooctyl, perfluoroethyl, and --CH.sub.2CF.sub.3.

As used herein, the term “hydrocarbylene” refers to a divalent hydrogen atom formed by removing two hydrogen atoms from a hydrocarbon, typically a (C ₁ -C ₄₀ ) hydrocarbon. means the base. Hydrocarbylene groups may be linear, branched or cyclic, and saturated or unsaturated. Examples of hydrocarbylene groups are methylene, ethylene, 1-methylethylene, 1-phenylethylene, propylene, butylene, 1,2-phenylene, 1,3-phenylene, 1,4-phenylene, and 2,6-naphthylene. including but not limited to.

As used herein, the term "alkoxy" means a monovalent group designated as -O-alkyl, wherein alkyl group is as defined herein. Examples of alkoxy groups include, but are not limited to, methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, and tert-butoxy.

As used herein, the term "aryl" refers to a monovalent unsaturated ring containing one or more six-membered carbocyclic rings, the unsaturation of which is represented by three conjugated double bonds. means a hydrocarbon group. Aryl groups include monocyclic aryl and polycyclic aryl. A polycyclic aryl is a monovalent unsaturated hydrocarbon group containing two or more six-membered carbocyclic rings, the unsaturation of which is represented by three conjugated double bonds, and adjacent A group in which rings are joined together or fused together by one or more bonds or divalent bridging groups. Examples of aryl groups include, but are not limited to, phenyl, anthracenyl, naphthyl, phenanthrenyl, fluorenyl, and pyrenyl.

As used herein, the term "aryloxy" means a monovalent radical designated as -O-aryl, wherein aryl group is as defined herein. Examples of aryloxy groups include, but are not limited to, phenoxy, anthracenoxy, naphthoxy, phenanthreoxy, and fluorenoxy.

Any substituent or group described herein may be optionally substituted at one or more carbon atoms by one or more of the same or different substituents described herein. For example, hydrocarbylene groups may be further substituted with aryl or alkyl groups. Any substituents or groups described herein may also be substituted at one or more carbon atoms, for example, halogen such as F, Cl, Br, and I; nitro (NO ₂ ), cyano (CN), and optionally substituted with one or more substituents selected from the group consisting of hydroxy (OH).

As used herein, charge-transporting is synonymous with conductivity and is also synonymous with hole-transporting. Further, the ink composition of the present invention may itself have charge-transporting properties, or may have charge-transporting properties in a solid film obtained by using the ink composition.

As used herein, a "hole carrier compound" is a compound that is capable of facilitating the movement of holes (i.e., positive charge carriers) and/or facilitates the movement of electrons, for example, in an electronic device. It refers to any compound that can be blocked. Hole carrier compounds are used in hole transport layers (HTL), hole injection layers (HIL) and electron blocking layers (EBL) of electronic devices, typically organic electronic devices (e.g., organic light emitting devices, etc.). Contains useful compounds.

As used herein, the term "doped" with respect to a hole carrier compound, such as polythiophene, means that the hole carrier compound has undergone a chemical transformation, typically oxidation or reduction, promoted by a dopant. It means that it has undergone a reaction, more typically an oxidation reaction. As used herein, the term "dopant" refers to a substance that oxidizes or reduces, typically oxidizes, a hole carrier compound such as polythiophene. As used herein, a process in which a hole carrier compound undergoes a chemical transformation, typically an oxidation or reduction reaction, more typically an oxidation reaction, promoted by a dopant is referred to as a "doping reaction" or simply "doping is called. Doping changes the properties of polythiophenes, which may include, but are not limited to, electrical properties (such as resistivity and work function), mechanical properties, and optical properties. During the doping reaction, the hole carrier compound becomes charged and the dopant becomes an oppositely charged counterion with respect to the doped hole carrier compound as a result of the doping reaction. As used herein, a substance must chemically react with, oxidize, or reduce, typically oxidize, a hole carrier compound to be called a dopant. Substances that do not react with the hole carrier compound but can act as counterions are not considered dopants for purposes of this disclosure. Thus, the term "undoped" with respect to a hole carrier compound, such as polythiophene, means that the hole carrier compound has not undergone the doping reaction described herein.

As used herein, "pile-up" means the phenomenon of the ink composition creeping up the sides of the bank.
Various methods for applying an ink composition are known. One example of such a method is an inkjet method in which the ink composition is ejected from a nozzle in the form of fine droplets and adhered to an object to be coated (droplets discharge method) can be mentioned. When a charge-transporting thin film is formed on a substrate using an inkjet method for the purpose of manufacturing an organic EL device, a bank (partition wall) is formed on a thin film electrode (in many cases, a patterned thin film electrode) formed on the substrate. ) is formed so that the necessary region on the thin film electrode becomes a film forming region surrounded by banks, and an ink composition is applied only to the film forming region by an inkjet method to form a charge transporting thin film. The method of forming is often adopted.

The charge-transporting thin film thus formed preferably has a uniform thickness over the entire thin film. In reality, however, the thickness of the charge-transporting thin film may become non-uniform, especially when it is formed by the method using banks as described above. An example of such a state is a state in which the peripheral thickness of the formed charge-transporting thin film increases along the direction from the center to the edge of the thin film. This is because the ink composition applied in the film-forming region creeps up the side surface of the bank, and the peripheral thickness of the formed coating film increases from the center to the edge of the coating film (in other words, the coating film (portion in contact with the side surface of the bank), the charge-transporting thin film formed from the coating film in this state has a non-uniform thickness as described above. become a state. In this specification, the phenomenon in which the ink composition crawls up the sides of the bank is referred to as "pile-up phenomenon" or simply "pile-up."

The ink composition of the present disclosure may be non-aqueous and may contain water, but is preferably non-aqueous from the viewpoint of process compatibility in inkjet coating and storage stability of the ink. As used herein, "non-aqueous" means that the total amount of water in the ink composition of the present disclosure is 0-2% by weight based on the total weight of the ink composition. Typically, the total amount of water in the ink composition is 0-1 wt%, more typically 0-0.5 wt%, based on the total weight of the ink composition. In some embodiments, water is substantially absent from the ink compositions of the present disclosure.

［式中、Ｒ_１及びＲ_２は、それぞれ独立に、Ｈ、アルキル、フルオロアルキル、アルコキシ、フルオロアルコキシ、アリールオキシ、－ＳＯ_３Ｍ、又は－Ｏ－［Ｚ－Ｏ］_ｐ－Ｒ_ｅであるか、あるいは、Ｒ_１及びＲ_２は、一緒になって－Ｏ－Ｚ－Ｏ－を形成し、ここで、Ｍは、Ｈ、アルカリ金属、アンモニウム、モノアルキルアンモニウム、ジアルキルアンモニウム、又はトリアルキルアンモニウムであり、Ｚは、場合によりハロゲン又はＹで置換されているヒドロカルビレン基（ここで、Ｙは、炭素数１～１０の直鎖又は分岐鎖のアルキル基又はアルコキシアルキル基であり、該アルキル基又はアルコキシアルキル基は、任意の位置がスルホン酸基で置換されていてもよい）であり、ｐは、１以上の整数であり、そしてＲ_ｅは、Ｈ、アルキル、フルオロアルキル、又はアリールである］で表される繰り返し単位を含む、ポリチオフェンである。（Ａ）成分は、単独でも、二種以上を併用してもよい。 [(A) component]
Component (A) has the formula (I):

[wherein R ₁ and R ₂ are each independently H, alkyl, fluoroalkyl, alkoxy, fluoroalkoxy, aryloxy, -SO ₃ M, or -O-[ZO] _p -R _e Alternatively, R ₁ and R ₂ together form -OZO-, where M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium and Z is a hydrocarbylene group optionally substituted with halogen or Y (where Y is a linear or branched alkyl or alkoxyalkyl group having 1 to 10 carbon atoms, and the alkyl or an alkoxyalkyl group may be substituted with a sulfonic acid group at any position), p is an integer greater than or equal to 1, and R _e is H, alkyl, fluoroalkyl, or aryl. is a polythiophene containing a repeating unit represented by Component (A) may be used alone or in combination of two or more.

In certain embodiments, R ₁ and R ₂ are each independently H, fluoroalkyl, -SO ₃ M, -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e , or —OR _f , or R ₁ and R ₂ together are —O—(CH ₂ ) _q —O—, where (CH ₂ ) _q is optionally substituted with Y wherein M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium, and each R _a , R _b , R _c , and R _d is , each independently H, halogen, alkyl, fluoroalkyl, or aryl; R _e is H, alkyl, _fluoroalkyl , or aryl; p is 1, 2, or 3; , alkyl, fluoroalkyl, or aryl; q is 1, 2, or 3, and Y is a linear or branched alkoxyalkyl group having 1 to 10 carbon atoms, the alkoxyalkyl group being Any position may be substituted with a sulfonic acid group.

In some embodiments, R ₁ is H and R ₂ is other than H. In such embodiments, repeat units are derived from 3-substituted thiophenes.

Polythiophenes may be regiorandom or regioregular compounds. Due to its asymmetric structure, polymerization of 3-substituted thiophenes produces a mixture of polythiophene structures containing three possible regiochemical bonds between repeat units. The three orientations available when two thiophene rings are attached are 2,2', 2,5' and 5,5' couplings. 2,2' (ie, head-to-head) and 5,5' (ie, tail-to-tail) couplings are referred to as regiorandom couplings. In contrast, 2,5' (ie, head-to-tail) couplings are called regioregular couplings. The degree of regioregularity can be, for example, about 0-100%, or about 25-99.9%, or about 50-98%. Regioregularity can be determined by standard methods known to those skilled in the art, eg, using NMR spectroscopy.

In some embodiments, the polythiophene is regioregular. In some embodiments, the regioregularity of the polythiophene can be at least about 85%, typically at least about 95%, more typically at least about 98%. In some embodiments, the degree of regioregularity may be at least about 70%, typically at least about 80%. In yet another embodiment, the regioregular polythiophene has a degree of regioregularity of at least about 90%, typically at least about 98%.

3-Substituted thiophene monomers (including polymers derived therefrom) are commercially available or can be prepared by methods known to those skilled in the art. Synthetic methods, doping methods, and polymer characterization, including pendant regioregular polythiophenes, are described, for example, in McCullough et al., US Pat. No. 6,602,974 and McCullough et al., US Pat. No. 6,166,172. provided to

In another embodiment R ₁ and R ₂ are both other than H. In such embodiments, repeat units are derived from 3,4-disubstituted thiophenes.

In some embodiments, R ₁ and R ₂ are each independently -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e , or -OR _f ; Alternatively, R ₁ and R ₂ together form -O-(CH ₂ ) _q -O-. In some embodiments, R ₁ and R ₂ are both -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e . R ₁ and R ₂ may be the same or different.

In certain embodiments, each R _a , R _b , R _c , and R _d is each independently H, (C ₁ -C ₈ )alkyl, (C ₁ -C ₈ )fluoroalkyl, or phenyl. and R _e is (C ₁ -C ₈ )alkyl, (C ₁ -C ₈ )fluoroalkyl, or phenyl.

In some embodiments, R ₁ and R ₂ are each -O[CH ₂ -CH ₂ -O] _p -R _e . In some embodiments, R ₁ and R ₂ are each -O[CH(CH ₃ )-CH ₂ -O] _p -R _e .

In some embodiments, R _e is methyl, propyl, or butyl.

In some embodiments, q is two.

In some embodiments, —O—(CH ₂ ) _q —O— is substituted with Y at one or more positions. In one embodiment, —O—(CH ₂ ) _q —O— is substituted with Y at one position.

In some embodiments, q is 2 and Y is a 3-sulfobutoxymethyl group. In this case the -O-(CH ₂ ) ₂ -O- group is preferably substituted in one position by a 3-sulfobutoxymethyl group.

で表される基（式中、Ｍは、Ｈ、アルカリ金属、アンモニウム、モノアルキルアンモニウム、ジアルキルアンモニウム、又はトリアルキルアンモニウムである）、及びこれらの組合せからなる群より選択される繰り返し単位を含む。 In some embodiments, the polythiophene has the formula:

(wherein M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium), and repeating units selected from the group consisting of combinations thereof.

で示される繰り返し単位は、下記式：

３－（２－（２－メトキシエトキシ）エトキシ）チオフェン［本明細書では３－ＭＥＥＴと呼ばれる］
で示される構造により表されるモノマーから誘導され；下記式：

で示される繰り返し単位は、下記式：

（式中、Ｍは、Ｈ、アルカリ金属、アンモニウム、モノアルキルアンモニウム、ジアルキルアンモニウム、又はトリアルキルアンモニウムである）
スルホン化３－（２－（２－メトキシエトキシ）エトキシ）チオフェン［本明細書ではスルホン化３－ＭＥＥＴと呼ばれる］
で示される構造により表されるモノマーから誘導され；下記式：

で示される繰り返し単位は、下記式：

３，４－ビス（２－（２－ブトキシエトキシ）エトキシ）チオフェン［本明細書では３，４－ジＢＥＥＴと呼ばれる］
で示される構造により表されるモノマーから誘導され；下記式：

で示される繰り返し単位は、下記式：

３，４－ビス（（１－プロポキシプロパン－２－イル）オキシ）チオフェン［本明細書では３，４－ジＰＰＴと呼ばれる］
で示される構造により表されるモノマーから誘導され、そして下記式：

で示される繰り返し単位は、下記式：

３，４－エチレンジオキシチオフェン
で示される構造により表されるモノマーから誘導される。 As will be apparent to those skilled in the art, the formula:

The repeating unit represented by is represented by the following formula:

3-(2-(2-methoxyethoxy)ethoxy)thiophene [referred to herein as 3-MEET]
derived from a monomer represented by the structure represented by the formula:

The repeating unit represented by is represented by the following formula:

(Where M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium)
Sulfonated 3-(2-(2-methoxyethoxy)ethoxy)thiophene [referred to herein as sulfonated 3-MEET]
derived from a monomer represented by the structure represented by the formula:

The repeating unit represented by is represented by the following formula:

3,4-bis(2-(2-butoxyethoxy)ethoxy)thiophene [referred to herein as 3,4-diBEET]
derived from a monomer represented by the structure represented by the formula:

The repeating unit represented by is represented by the following formula:

3,4-bis((1-propoxypropan-2-yl)oxy)thiophene [referred to herein as 3,4-diPPT]
is derived from a monomer represented by the structure shown in and having the formula:

The repeating unit represented by is represented by the following formula:

It is derived from a monomer represented by the structure shown in 3,4-ethylenedioxythiophene.

3,4-disubstituted thiophene monomers (including polymers derived therefrom) are commercially available or can be prepared by methods known to those skilled in the art. For example, a 3,4-disubstituted thiophene monomer can be 3,4-dibromothiophene with the formula: HO-[ZO] _p -R _e or HOR _f where Z, R _e , R _f and p are , as defined herein] with a metal salt, typically the sodium salt.

Polymerization of 3,4-disubstituted thiophene monomers involves first brominating the 2 and 5 positions of the 3,4-disubstituted thiophene monomer to give the corresponding 2,5-dibromo derivative of the 3,4-disubstituted thiophene monomer. It is carried out by forming Polymers can then be obtained by GRIM (Grignard metathesis) polymerization of 2,5-dibromo derivatives of 3,4-disubstituted thiophenes in the presence of nickel catalysts. Such methods are described, for example, in US Pat. No. 8,865,025, which is incorporated herein by reference in its entirety. Another known method of polymerizing thiophene monomers uses a metal-free organic oxidant such as 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as the oxidant, or , for example by oxidative polymerization using transition metal halides such as iron(III) chloride, molybdenum(V) chloride, and ruthenium(III) chloride.

Compounds having the formula: HO-[ZO] _p -R _e or HOR _f that can be converted to metal salts, typically sodium salts, and used to generate 3,4-disubstituted thiophene monomers Examples of are trifluoroethanol, ethylene glycol monohexyl ether (hexylcellosolve), propylene glycol monobutyl ether (Dowanol™ PnB), diethylene glycol monoethyl ether (ethyl carbitol), dipropylene glycol n-butyl ether (Dowanol™ ) DPnB), diethylene glycol monophenyl ether (phenyl carbitol), ethylene glycol monobutyl ether (butyl cellosolve), diethylene glycol monobutyl ether (butyl carbitol), dipropylene glycol monomethyl ether (Dowanol™ DPM), diisobutyl carbinol, 2- Ethylhexyl Alcohol, Methyl Isobutyl Carbinol, Ethylene Glycol Monophenyl Ether (Dowanol™ Eph), Propylene Glycol Monopropyl Ether (Dowanol™ PnP), Propylene Glycol Monophenyl Ether (Dowanol™ PPh), Diethylene Glycol Monopropyl ether (propyl carbitol), diethylene glycol monohexyl ether (hexyl carbitol), 2-ethylhexyl carbitol, dipropylene glycol monopropyl ether (Dowanol™ DPnP), tripropylene glycol monomethyl ether (Dowanol™ TPM), Including, but not limited to, diethylene glycol monomethyl ether (methyl carbitol), and tripropylene glycol monobutyl ether (Dowanol™ TPnB).

Polythiophenes having repeat units of formula (I) of the present disclosure can be further modified following their formation by polymerization. For example, a polythiophene having one or more repeating units derived from a 3-substituted thiophene monomer can have one or more hydrogens replaced by a substituent such as a sulfonic acid group (—SO ₃ H) by sulfonation. You may have a part of

As used herein, the term “sulfonated” in relation to polythiophene means that the polythiophene contains one or more sulfonic acid groups (—SO ₃ H). (The polythiophene is also called "sulfonated polythiophene".)
Typically, the sulfur atoms of the —SO ₃ H group are directly attached to the polythiophene backbone and are not attached to side groups. For the purposes of this disclosure, a pendant group is a monovalent group that, when theoretically or actually eliminated from a polymer, does not reduce the length of the polymer chain. Sulfonated polythiophene polymers and/or copolymers can be made using any method known to those skilled in the art. For example, polythiophenes can be sulfonated by reacting with a sulfonating reagent such as, for example, oleum, acetyl sulfate, pyridine SO3 _, and the like. In another example, a monomer can be sulfonated using a sulfonating reagent and then polymerized by known methods and/or methods described herein. As will be apparent to those skilled in the art, sulfonic acid groups can be added to basic compounds such as alkali metal hydroxides, ammonia and alkylamines (such as mono-, di- and trialkylamines such as triethylamine, etc.). In its presence, it may lead to the formation of the corresponding salt or adduct. Thus, the term “sulfonated” in relation to polythiophene means that the polythiophene has one or more —SO ₃ M groups, where M is an alkali metal ion (eg, Na ⁺ , Li ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ etc.), ammonium (NH ₄ ⁺ ), mono-, di-, and trialkylammonium (such as triethylammonium)).

Sulfonation of conjugated polymers and sulfonated conjugated polymers (including sulfonated polythiophenes) are described in Seshadri et al., US Pat. No. 8,017,241, which is incorporated herein by reference in its entirety. be
Sulfonated polythiophenes are also described in WO2008/073149 and WO2016/171935, which are hereby incorporated by reference in their entireties.

In some embodiments, the polythiophene is sulfonated.

［式中、Ｒ_１及びＲ_２は、それぞれ独立に、Ｈ、アルキル、フルオロアルキル、アルコキシ、フルオロアルコキシ、アリールオキシ、又は－Ｏ－［Ｚ－Ｏ］_ｐ－Ｒ_ｅ（式中、Ｚは、場合によりハロゲン化されているヒドロカルビレン基であり、ｐは、１以上の整数であり、そして、Ｒ_ｅは、Ｈ、アルキル、フルオロアルキル、又はアリールである）である。
但し、Ｒ_１及びＲ_２のいずれかは、－ＳＯ_３Ｍ（Ｍは、Ｈ、アルカリ金属、アンモニウム、モノアルキルアンモニウム、ジアルキルアンモニウム、又はトリアルキルアンモニウムである。）である。］
で表される繰り返し単位を含む。 In certain embodiments, the sulfonated polythiophene has formula (I):

[wherein R ₁ and R ₂ are each independently H, alkyl, fluoroalkyl, alkoxy, fluoroalkoxy, aryloxy, or -O-[Z-O] _p -R _e (wherein Z is optionally halogenated hydrocarbylene group, p is an integer greater than or equal to 1, and R _e is H, alkyl, fluoroalkyl, or aryl.
However, either of R ₁ and R ₂ is —SO ₃ M (M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium or trialkylammonium). ]
Including repeating units represented by

In certain embodiments, the sulfonated polythiophene has the formula (I) [wherein each R ₁ and R ₂ is independently H, fluoroalkyl, -O[C(R _a R _b )-C(R _c R _d )—O] _p —R _e , or —OR _f ; wherein each R _a , R _b , R _c , and R _d is independently H, halogen, alkyl, fluoroalkyl , or aryl; R _e is H, alkyl, fluoroalkyl, or aryl; p is 1, 2, or 3; and R _f is alkyl, fluoroalkyl, or aryl.
However, either of R ₁ and R ₂ is —SO ₃ M (M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium or trialkylammonium). ]
Including repeating units represented by

In some embodiments, R ₁ is —SO ₃ M (M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium), and R ₂ is —SO ₃ Other than M. M is preferably monoalkylammonium, dialkylammonium or trialkylammonium, more preferably trialkylammonium.

In some embodiments, R ₁ is -SO ₃ M and R ₂ is -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e , or -OR is _f .

In some embodiments, R ₁ is -SO ₃ M and R ₂ is -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e .

In some embodiments, R ₁ is -SO ₃ M and R ₂ is -O-CH ₂ CH ₂ -O-CH ₂ CH ₂ -O-CH ₃ .

［式中、Ｒ_１及びＲ_２は、それぞれ独立に、Ｈ、アルキル、フルオロアルキル、アルコキシ、フルオロアルコキシ、アリールオキシ、又は－Ｏ－［Ｚ－Ｏ］_ｐ－Ｒ_ｅ（式中、Ｚは、場合によりハロゲン化されているヒドロカルビレン基であり、ｐは、１以上の整数であり、そして、Ｒ_ｅは、Ｈ、アルキル、フルオロアルキル、又はアリールである）である］
で表される繰り返し単位を含むポリチオフェンのスルホン化により得られる。 In some embodiments, the sulfonated polythiophene has formula (I):

[wherein R ₁ and R ₂ are each independently H, alkyl, fluoroalkyl, alkoxy, fluoroalkoxy, aryloxy, or -O-[Z-O] _p -R _e (wherein Z is optionally halogenated hydrocarbylene group, p is an integer greater than or equal to 1, and R _e is H, alkyl, fluoroalkyl, or aryl]
obtained by sulfonation of a polythiophene containing repeating units represented by

In certain embodiments, the sulfonated polythiophene has the formula (I) [wherein R ₁ and R ₂ are each independently H, fluoroalkyl, -O[C(R _a R _b )-C(R _c R _d ) —O] _p —R _e , or —OR _f ; wherein each R _a , R _b , R _c , and R _d is each independently H, halogen, alkyl, fluoroalkyl, or is aryl; R _e is H, alkyl, fluoroalkyl, or aryl; p is 1, 2, or 3; and R _f is alkyl, fluoroalkyl, or aryl] obtained by sulfonation of polythiophene containing repeating units.

In some embodiments, R ₁ is H and R ₂ is other than H. In such embodiments, repeat units are derived from 3-substituted thiophenes.

Sulfonated polythiophenes are derived from polythiophenes which can be regiorandom or regioregular compounds. Due to its asymmetric structure, polymerization of 3-substituted thiophenes produces a mixture of polythiophene structures containing three possible regiochemical bonds between repeat units. The three orientations available when two thiophene rings are attached are 2,2', 2,5' and 5,5' couplings. 2,2' (ie, head-to-head) and 5,5' (ie, tail-to-tail) couplings are referred to as regiorandom couplings. In contrast, 2,5' (ie, head-to-tail) couplings are called regioregular couplings. The degree of regioregularity can be, for example, about 0-100%, or about 25-99.9%, or about 50-98%. Regioregularity can be determined by standard methods known to those skilled in the art, eg, using NMR spectroscopy.

3-Substituted thiophene monomers (including polymers derived therefrom) are commercially available or can be prepared by methods known to those skilled in the art. Synthetic methods, doping methods, and polymer characterization, including pendant regioregular polythiophenes, are described, for example, in McCullough et al., US Pat. No. 6,602,974 and McCullough et al., US Pat. No. 6,166,172. provided to Sulfonation of conjugated polymers and sulfonated conjugated polymers (including sulfonated polythiophenes) are described in US Pat. No. 8,017,241 to Seshadri et al.

In some embodiments, R ₁ is H and R ₂ is -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e , or -OR _f . In some embodiments, R ₁ is H and R ₂ is -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e .

In some embodiments, each R _a , R _b , R _c , and R _d is each independently H, (C ₁ -C ₈ )alkyl, (C ₁ -C ₈ )fluoroalkyl, or phenyl. R _e and R _f are each independently H, (C ₁ -C ₈ )alkyl, (C ₁ -C ₈ )fluoroalkyl, or phenyl;

In some embodiments, R ₂ is -O[CH ₂ -CH ₂ -O] _p -R _e . In some embodiments, R ₂ is -OR _f .

It can be converted to a metal salt, typically the sodium salt, and coupled to the thiophene monomer to form a 3-substituted thiophene, which is then used to form the polythiophene to be sulfonated. , HO[C(R _a R _b )-C(R _c R _d )-O] _p -R _e or HOR _f are trifluoroethanol, ethylene glycol monohexyl ether (hexylcellosolve) , propylene glycol monobutyl ether (Dowanol™ PnB), diethylene glycol monoethyl ether (ethyl carbitol), dipropylene glycol n-butyl ether (Dowanol™ DPnB), diethylene glycol monophenyl ether (phenyl carbitol), ethylene glycol mono Butyl Ether (Butyl Cellosolve), Diethylene Glycol Monobutyl Ether (Butyl Carbitol), Dipropylene Glycol Monomethyl Ether (Dowanol™ DPM), Diisobutyl Carbinol, 2-Ethylhexyl Alcohol, Methylisobutyl Carbinol, Ethylene Glycol Monophenyl Ether (Dowanol™ ) Eph), propylene glycol monopropyl ether (Dowanol™ PnP), propylene glycol monophenyl ether (Dowanol™ PPh), diethylene glycol monopropyl ether (propyl carbitol), diethylene glycol monohexyl ether (hexyl carbitol), 2-ethylhexyl carbitol, dipropylene glycol monopropyl ether (Dowanol™ DPnP), tripropylene glycol monomethyl ether (Dowanol™ TPM), diethylene glycol monomethyl ether (methyl carbitol), and tripropylene glycol monobutyl ether (Dowanol (trademark) TPnB).

In some embodiments, R _e is H, methyl, propyl, or butyl. In some embodiments, R _f is CH ₂ CF ₃ .

で示される繰り返し単位を含むポリチオフェンをスルホン化することにより得られる。 In some embodiments, the sulfonated polythiophene has the formula:

obtained by sulfonating a polythiophene containing repeating units represented by

で示される繰り返し単位は、下記式：

３－（２－（２－メトキシエトキシ）エトキシ）チオフェン［本明細書では３－ＭＥＥＴと呼ばれる］
で示される構造により表されるモノマーから誘導される。 As will be apparent to those skilled in the art, the formula:

The repeating unit represented by is represented by the following formula:

3-(2-(2-methoxyethoxy)ethoxy)thiophene [referred to herein as 3-MEET]
is derived from a monomer represented by the structure shown in

で示される繰り返し単位を含むポリチオフェンのスルホン化により、スルホン化ポリ（３－ＭＥＥＴ）が生じる。 Therefore, the formula:

Sulfonation of polythiophenes containing repeating units represented by yields sulfonated poly(3-MEET).

In some embodiments, the polythiophene is sulfonated poly(3-MEET).

Polythiophenes used in this disclosure may be homopolymers or copolymers (including statistical, random, gradient, and block copolymers). For polymers comprising monomer A and monomer B, block copolymers include, for example, AB diblock copolymers, ABA triblock copolymers, and -(AB) _k -multiblock copolymers. Polythiophenes contain repeat units derived from other types of monomers such as thienothiophenes, selenophenes, pyrroles, furans, tellurophenes, anilines, arylamines, and arylenes such as phenylenes, phenylene vinylenes, and fluorenes. may contain.

In certain embodiments, the polythiophene comprises greater than 50% by weight, typically greater than 80% by weight, more typically greater than 90% by weight of repeating units of formula (I), based on the total weight of the repeating units. greater than 95% by weight, and even more typically greater than 95% by weight.

As will be apparent to those skilled in the art, depending on the purity of the starting monomeric compounds used in the polymerization, the polymer formed may contain repeat units derived from impurities. As used herein, the term "homopolymer" shall mean a polymer containing repeat units derived from one type of monomer, but containing repeat units derived from impurities. good too. In one embodiment, the polythiophene is a homopolymer in which essentially all repeating units are repeating units of formula (I).

Polythiophenes typically have number average molecular weights between about 1,000 and 1,000,000 g/mol. More typically, the conjugated polymer has a number average molecular weight of about 5,000 to 100,000 g/mol, even more typically between about 10,000 and about 50,000 g/mol. Number average molecular weight can be determined by methods known to those skilled in the art, such as, for example, gel permeation chromatography.

［式中、Ｒ_１及びＲ_２は、式（Ｉ）において定義された通りである。］ In the present invention, the above polythiophene may be used after being treated with a reducing agent.
In polythiophenes, some of the repeating units constituting them may have an oxidized chemical structure called a "quinoid structure". The term "quinoid structure" is used for the term "benzenoid structure", the latter being a structure containing an aromatic ring, whereas the former is a structure in which the double bond within the aromatic ring moves out of the ring (the As a result, the aromatic ring disappears), meaning a structure in which two exocyclic double bonds conjugated with other double bonds remaining in the ring are formed. For those skilled in the art, the relationship between these two structures can be readily understood from the structural relationship between benzoquinone and hydroquinone. Quinoid structures for repeating units of various conjugated polymers are well known to those skilled in the art. As an example, a quinoid structure corresponding to the repeating unit of the polythiophene represented by formula (I) is shown in formula (I') below.

[wherein R ₁ and R ₂ are as defined in formula (I). ]

This quinoid structure forms a part of the structures called "polaron structure" and "bipolaron structure" which are generated by the doping reaction and which impart charge transport properties to polythiophene. These structures are known. The introduction of a "polaron structure" and/or a "bipolaron structure" is essential in the production of organic EL elements, and in practice, the charge-transporting thin film formed from the charge-transporting varnish is baked when the organic EL element is produced. Sometimes this is achieved by deliberately causing the doping reactions described above. The quinoid structure is contained in the polythiophene before the doping reaction is caused because the polythiophene has the same This is considered to be due to an unintended oxidation reaction.

There is a correlation between the amount of quinoid structure contained in polythiophene and the dispersibility of polythiophene in an organic solvent. As the amount of quinoid structure increases, the dispersibility decreases. Therefore, the introduction of the quinoid structure after the formation of the charge-transporting thin film from the ink composition does not cause any problem, but if the quinoid structure is excessively introduced into the polythiophene due to the unintended oxidation reaction, It interferes with the production of the ink composition. It is known that polythiophene varies in its dispersibility in organic solvents. One of the reasons for this is that the amount of quinoid structure introduced into polythiophene by the unintended oxidation reaction described above is different from that of each polythiophene. It is considered that it fluctuates according to the difference in manufacturing conditions.
Therefore, when polythiophene is subjected to a reduction treatment using a reducing agent, even if the quinoid structure is excessively introduced into the polythiophene, the reduction reduces the quinoid structure and improves the dispersibility of the polythiophene in an organic solvent. It is possible to stably produce a good ink composition that gives a charge-transporting thin film excellent in .

The reducing agent used in this reduction treatment reduces the quinoid structure to convert it into a non-oxidized structure, that is, the benzenoid structure (for example, in the polythiophene represented by the formula (I), the formula (I ') is not particularly limited as long as it can convert the quinoid structure represented by formula (I) to the structure represented by the formula (I). For example, it is preferable to use aqueous ammonia, hydrazine, or the like. The amount of the reducing agent is generally 0.1-10 parts by weight, preferably 0.5-2 parts by weight, per 100 parts by weight of the polythiophene to be treated.

There are no particular restrictions on the method and conditions of the reduction treatment. For example, this treatment can be carried out simply by contacting the polythiophene with a reducing agent, in the presence or absence of a suitable solvent. Generally, reduction treatment under relatively mild conditions such as stirring polythiophene in 28% aqueous ammonia (for example, overnight at room temperature) sufficiently improves the dispersibility of polythiophene in organic solvents.
In the case of sulfonated polythiophenes, if necessary, the sulfonated polythiophenes may be converted to the corresponding ammonium salts, such as trialkylammonium salts (sulfonated polythiophene amine adducts), prior to reduction treatment.

As a result of this reduction treatment changing the dispersibility of the polythiophene in the solvent, the polythiophene that was not dissolved in the reaction system at the start of the treatment may be dissolved at the completion of the treatment. In such a case, an organic solvent incompatible with polythiophene (in the case of sulfonated polythiophene, acetone, isopropyl alcohol, etc.) is added to the reaction system to precipitate polythiophene, followed by filtering. Polythiophene can be recovered.

The ink composition may optionally further contain a hole carrier compound other than component (A) as long as the effects of the present invention are not impaired.

Optional hole carrier compounds include, for example, low molecular weight compounds or high molecular weight compounds. The optional hole carrier compound can be non-polymeric or polymeric. Non-polymeric hole carrier compounds include, but are not limited to, crosslinkable small molecules and non-crosslinked small molecules. Examples of non-polymeric hole carrier compounds are N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)benzidine (CAS # 65181-78-4); 4-methylphenyl)-N,N'-bis(phenyl)benzidine; N,N'-bis(2-naphthalenyl)-N,N'-bis(phenylbenzidine) (CAS # 139255-17-1); 1 ,3,5-tris(N,N-bis(3-methylphenyl)amino)benzene (also called m-MTDAB); N,N′-bis(1-naphthalenyl)-N,N′-bis(phenyl) Benzidine (CAS # 123847-85-8, NPB); 4,4′,4″-tris(N,N-phenyl-3-methylphenylamino)triphenylamine (also called m-MTDATA, CAS # 124729-98 -2); 4,4′-bis(carbazol-9-yl)biphenyl (also called CBP, CAS # 58328-31-7); 1,3,5-tris(diphenylamino)benzene; 1,3,5 -tris(2-(9-ethylcarbazyl-3)ethylene)benzene; 1,3,5-tris[(3-methylphenyl)phenylamino]benzene; 1,3-bis(N-carbazolyl)benzene; 1 ,4-bis(diphenylamino)benzene;4,4'-bis(N-carbazolyl)-1,1'-biphenyl;4-(dibenzylamino)benzaldehyde-N,N-diphenylhydrazone;4-(diethylamino) 4-(Diphenylamino)benzaldehyde diphenylhydrazone; 4-(diphenylamino)benzaldehyde diphenylhydrazone; 9-ethyl-3-carbazolecarboxaldehyde diphenylhydrazone; copper (II) phthalocyanine; -methylphenyl)-N,N'-diphenylbenzidine; N,N'-di(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine; N,N' -diphenyl-N,N'-di-p-tolylbenzene-1,4-diamine; tetra-N-phenylbenzidine; titanyl phthalocyanine; tri-p-tolylamine; tris(4-carbazol-9-ylphenyl)amine; and tris[4-(diethylamino)phenyl]amine.

An optional polymeric hole carrier compound is poly[(9,9-dihexylfluorenyl-2,7-diyl)-alt-co-(N,N'-bis{p-butylphenyl}-1,4- diaminophenylene)]; poly[(9,9-dioctylfluorenyl-2,7-diyl)-alt-co-(N,N′-bis{p-butylphenyl}-1,1′-biphenylene-4 ,4′-diamine)]; poly(9,9-dioctylfluorene-co-N-(4-butylphenyl)diphenylamine) (also called TFB) and poly[N,N′-bis(4-butylphenyl)- N,N'-bis(phenyl)-benzidine] (commonly referred to as poly-TPD).

Other optional hole carrier compounds are, for example, U.S. Patent Application Publication No. 2010/0292399, published November 18, 2010; U.S. Patent Application Publication No. 2010/0109000, published May 6, 2010; and in US Patent Application Publication No. 2010/0108954, published May 6, 2010. Optional hole carrier compounds described herein are known in the art and commercially available.

で表されるアニオン、及び式（ａ２）：

で表される１価又は２価のアニオン
［式中、Ａｒは、それぞれ独立して、置換基を有してもよいアリール基又は置換基を有してもよいヘテロアリール基であり、Ｒは、炭素数１～１０のアルキル基、炭素数３～２０のシクロアルキル基、炭素数１～１０のフルオロアルキル基、炭素数７～１０のアラルキル基又は炭素数７～１０のフルオロアラルキル基であり、Ｌは、アルキレン基、－ＮＨ－、酸素原子、硫黄原子又は－ＣＮ⁺－である］からなる群より選択される少なくとも１種のアニオンと対カチオンとからなるオニウムボレート塩（ただし、電気的中性な塩である）である。 [(B) component]
Component (B) is an onium borate salt represented by formula (a1):

and an anion of formula (a2):

A monovalent or divalent anion represented by [Wherein Ar is each independently an optionally substituted aryl group or optionally substituted heteroaryl group, R is , an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or a fluoroaralkyl group having 7 to 10 carbon atoms. , L is an alkylene group, —NH—, an oxygen atom, a sulfur atom, or —CN ⁺ —. is a neutral salt).

The component (B) functions as a dopant that oxidizes the polythiophene of the component (A) and improves electrical properties (resistivity, work function, etc.). When an onium borate salt composed of an anion represented by formula (a1) or (a2) and a counter cation represented by the formula (a1) or (a2) is used as a dopant, as in the component (B), the electrical properties of the polythiophene can be greatly improved. An ink composition having excellent transportability can be obtained.

In formulas (a1) and (a2), each Ar is independently an optionally substituted aryl group or an optionally substituted heteroaryl group.

Examples of the aryl group include aryl groups having 6 to 20 carbon atoms. Specific examples include a phenyl group, a tolyl group, a 1-naphthyl group, a 2-naphthyl group, a 1-anthryl group, a 2-anthryl group, a 9-anthryl group, a 1-phenanthryl group, a 2-phenanthryl group, and a 3-phenanthryl group. group, 4-phenanthryl group, 9-phenanthryl group and the like, with phenyl group, tolyl group and naphthyl group being preferred.

Heteroaryl groups preferably include heteroaryl groups having 2 to 20 carbon atoms. Specific examples thereof include a 2-thienyl group, a 3-thienyl group, a 2-furanyl group, a 3-furanyl group, a 2-oxazolyl group, a 4-oxazolyl group, a 5-oxazolyl group, a 3-isoxazolyl group, and a 4-isoxazolyl group. , an oxygen-containing heteroaryl group such as a 5-isoxazolyl group, a 2-thiazolyl group, a 4-thiazolyl group, a 5-thiazolyl group, a 3-isothiazolyl group, a 4-isothiazolyl group, a sulfur-containing heteroaryl group such as a 5-isothiazolyl group, 2-imidazolyl group, 4-imidazolyl group, 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, 2-pyrazyl group, 3-pyrazyl group, 5-pyrazyl group, 6-pyrazyl group, 2-pyrimidyl group, 4-pyrimidyl group, 5-pyrimidyl group, 6-pyrimidyl group, 3-pyridazyl group, 4-pyridazyl group, 5-pyridazyl group, 6-pyridazyl group, 1,2,3-triazin-4-yl group, 1, 2,3-triazin-5-yl group, 1,2,4-triazin-3-yl group, 1,2,4-triazin-5-yl group, 1,2,4-triazin-6-yl group, 1,3,5-triazin-2-yl group, 1,2,4,5-tetrazin-3-yl group, 1,2,3,4-tetrazin-5-yl group, 2-quinolinyl group, 3- quinolinyl group, 4-quinolinyl group, 5-quinolinyl group, 6-quinolinyl group, 7-quinolinyl group, 8-quinolinyl group, 1-isoquinolinyl group, 3-isoquinolinyl group, 4-isoquinolinyl group, 5-isoquinolinyl group, 6- isoquinolinyl group, 7-isoquinolinyl group, 8-isoquinolinyl group, 2-quinoxanyl group, 5-quinoxanyl group, 6-quinoxanyl group, 2-quinazolinyl group, 4-quinazolinyl group, 5-quinazolinyl group, 6-quinazolinyl group, 7- nitrogen-containing heteroaryl groups such as a quinazolinyl group, 8-quinazolinyl group, 3-cinnolinyl group, 4-cinnolinyl group, 5-cinnolinyl group, 6-cinnolinyl group, 7-cinnolinyl group, 8-cinnolinyl group;

Examples of the substituent include a halogen atom, a nitro group, a cyano group, an alkyl group having 1 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms and an alkynyl group having 2 to 20 carbon atoms.

A halogen atom includes a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like, and a fluorine atom is preferable.

The alkyl group having 1 to 20 carbon atoms may be linear, branched or cyclic, and specific examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl group, s-butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group, n-decyl group, n-undecyl group, n- dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, n-eicosanyl group and the like. An alkyl group having 1 to 18 carbon atoms is preferred, and an alkyl group having 1 to 8 carbon atoms is more preferred.

Specific examples of alkenyl groups having 2 to 20 carbon atoms include ethenyl group, n-1-propenyl group, n-2-propenyl group, 1-methylethenyl group, n-1-butenyl group, n-2-butenyl group, n-3-butenyl group, 2-methyl-1-propenyl group, 2-methyl-2-propenyl group, 1-ethylethenyl group, 1-methyl-1-propenyl group, 1-methyl-2-propenyl group, n- 1-pentenyl group, n-1-decenyl group, n-1-eicosenyl group and the like.

Specific examples of alkynyl groups having 2 to 20 carbon atoms include ethynyl, n-1-propynyl, n-2-propynyl, n-1-butynyl, n-2-butynyl and n-3-butynyl. group, 1-methyl-2-propynyl group, n-1-pentynyl group, n-2-pentynyl group, n-3-pentynyl group, n-4-pentynyl group, 1-methyl-n-butynyl group, 2- methyl-n-butynyl group, 3-methyl-n-butynyl group, 1,1-dimethyl-n-propynyl group, n-1-hexynyl group, n-1-decynyl group, n-1-pentadecynyl group, n- 1-eicosinyl group and the like.

Ar is preferably an aryl group having one or more electron-withdrawing substituents. It is preferable that Ar is an aryl group having an electron-withdrawing substituent, since the Lewis acidity is improved. Examples of the electron-withdrawing group include a halogen atom, a nitro group, a cyano group, etc. A halogen atom is preferred, and a fluorine atom is particularly preferred. Ar is particularly preferably a pentafluorophenyl group.

で表されるアニオンと対カチオンとからなるオニウムボレート塩が、特に好ましい。 When component (B) is an onium borate salt consisting of an anion represented by formula (a1) and a counter cation, formula (a4):

An onium borate salt consisting of an anion represented by and a counter cation is particularly preferred.

In formula (a1), R is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms, or 7 carbon atoms. ∼10 fluoroaralkyl groups.

The alkyl group having 1 to 10 carbon atoms may be linear, branched or cyclic, and examples thereof include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, s -Linear or branched chain having 1 to 10 carbon atoms such as butyl group, t-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, n-nonyl group and n-decyl group A chain alkyl group and the like can be mentioned, and an alkyl group having 1 to 8 carbon atoms is preferable, and an alkyl group having 1 to 6 carbon atoms is more preferable.

Cycloalkyl groups having 3 to 20 carbon atoms include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, bicyclobutyl, bicyclopentyl and bicyclohexyl groups. , a bicycloheptyl group, a bicyclooctyl group, a bicyclononyl group, a bicyclodecyl group, and other cyclic alkyl groups having 3 to 20 carbon atoms.

Specific examples of fluoroalkyl groups having 1 to 10 carbon atoms include groups in which at least one hydrogen atom of an alkyl group having 1 to 10 carbon atoms is substituted with a fluorine atom.
Specific examples thereof include a fluoromethyl group, a difluoromethyl group, a trifluoromethyl group, a pentafluoroethyl group, a 2,2,2-trifluoroethyl group, a heptafluoropropyl group, a 2,2,3,3,3- pentafluoropropyl group, 2,2,3,3-tetrafluoropropyl group, 2,2,2-trifluoro-1-(trifluoromethyl)ethyl group, nonafluorobutyl group, 4,4,4-trifluoro butyl group, undecafluoropentyl group, 2,2,3,3,4,4,5,5,5-nonafluoropentyl group, 2,2,3,3,4,4,5,5-octafluoro pentyl group, tridecafluorohexyl group, 2,2,3,3,4,4,5,5,6,6,6-undecafluorohexyl group, 2,2,3,3,4,4, 5,5,6,6-decafluorohexyl group, 3,3,4,4,5,5,6,6,6-nonafluorohexyl group and the like.

Aralkyl groups having 7 to 10 carbon atoms include groups in which at least one hydrogen atom of an alkyl group is substituted with an aryl group, such as benzyl, 1-naphthylmethyl, 2-naphthylmethyl, phenylethyl, group, 1-naphthylethyl group, 2-naphthylmethyl group and the like, and an aralkyl group having 7 to 9 carbon atoms is preferred.

Specific examples of fluoroaralkyl groups having 7 to 10 carbon atoms include groups in which at least one hydrogen atom of an aralkyl group having 7 to 10 carbon atoms is substituted with a fluorine atom.
Specific examples include perfluorobenzyl group, pentafluorophenylmethyl group, heptafluoro-1-naphthylmethyl group, heptafluoro-2-naphthylmethyl group, heptafluoro-1-naphthylethyl group, heptafluoro-2-naphthyl An ethyl group etc. are mentioned.

Among these, R in formula (a1) is preferably an alkyl group having 1 to 6 carbon atoms. Examples of anions represented by formula (a1) that can be suitably used in the present invention include those represented by the following formulas, but are not limited thereto.

In formula (a2), L is an alkylene group, -NH-, an oxygen atom, a sulfur atom or -CN ⁺ -. The alkylene group may be linear, branched or cyclic, and includes alkylene groups having 1 to 20 carbon atoms, preferably 1 to 10 carbon atoms. Specific examples include a methylene group, a methylmethylene group, a dimethylmethylene group, an ethylene group, a trimethylene group, a propylene group, a tetramethylene group, a pentamethylene group, and a hexamethylene group.

It is particularly preferred that L is -CN ⁺ -.

で表されるアニオンと対カチオンとからなるオニウムボレート塩が、特に好ましい。 When component (B) is an onium borate salt consisting of an anion represented by formula (a2) and a counter cation, formula (a3):

An onium borate salt consisting of an anion represented by and a counter cation is particularly preferred.

The counter cation of component (B) is not particularly limited, but a cation containing an element belonging to Groups 15 to 17 is preferred, and a cation containing sulfur is more preferred.

からなる群より選択されることが好ましい。中でも、対カチオンが（ｃ１）で表されるカチオンは、特に好ましい。 The counter cation of component (B) is represented by formulas (c1) to (c5):

It is preferably selected from the group consisting of Among them, a cation whose counter cation is represented by (c1) is particularly preferred.

で表されるオニウムボレート塩であることが特に好ましい。 Component (B) has the following formula:

An onium borate salt represented by is particularly preferred.

(B) component may be used individually by 1 type, or may be used in combination of 2 or more types. In addition, other known onium borate salts may be used in combination, if necessary. The component (B) can be synthesized with reference to known methods described in, for example, JP-A-2005-314682.

The ratio of component (A) and component (B) can be (A):component (B) = 1:0.01 to 15, preferably 1: 0.1-10, more preferably 1:0.5-5. It is preferable from the viewpoint of device characteristics that the ratio of the component (A) and the component (B) is within this range.

In order to facilitate dissolution in the ink composition, the component (B) may be dissolved in advance in an organic solvent constituting the liquid carrier (C) described later.
Examples of such organic solvents include carbonates such as propylene carbonate, ethylene carbonate, 1,2-butylene carbonate, dimethyl carbonate and diethyl carbonate; ketones such as acetone, methyl ethyl ketone, cyclohexanone, methyl isoamyl ketone and 2-heptanone; ethylene Glycol, ethylene glycol monoacetate, diethylene glycol, diethylene glycol monoacetate, propylene glycol, propylene glycol monoacetate, dipropylene glycol, monomethyl ether, monoethyl ether, monopropyl ether, monobutyl ether, monophenyl ether or triphenyl ether of dipropylene glycol monoacetate. Polyhydric alcohols such as ethylene glycol dimethyl ether and derivatives thereof; Cyclic ethers such as dioxane; Ethyl formate, methyl lactate, ethyl lactate, methyl acetate, ethyl acetate, butyl acetate, methyl pyruvate, methyl acetoacetate, ethyl acetoacetate , ethyl pyruvate, ethyl ethoxyacetate, methyl methoxypropionate, ethyl ethoxypropionate, methyl 2-hydroxypropionate, ethyl 2-hydroxypropionate, ethyl 2-hydroxy-2-methylpropionate, 2-hydroxy-3- Esters such as methyl methylbutanoate, 3-methoxybutyl acetate, and 3-methyl-3-methoxybutyl acetate; Aromatic hydrocarbons and the like may be mentioned, and these may be used alone or in combination of two or more.
When an organic solvent is used, its usage ratio is preferably 15 to 1,000 parts by weight, more preferably 30 to 500 parts by weight, per 100 parts by weight of component (B).

The ink composition may contain a dopant other than the component (B) as long as it does not interfere with the purpose of the present application. Dopants are known in the art. See, for example, US Patent No. 7,070,867; US Patent Application Publication No. 2005/0123793; and US Patent Application Publication No. 2004/0113127. The dopant may be an ionic compound. Dopants can include cations and anions.

The cations of the ionic compounds are, for example, V, Cr, Mn, Fe, Co, Ni, Cu, Nb, Mo, Tc, Ru, Rh, Pd, Ag, Ta, W, Re, Os, Ir, Pt, or Au may be used.

The cations of the ionic compounds can be, for example, gold, molybdenum, rhenium, iron, and silver cations.

In some embodiments, dopants may include sulfonates or carboxylates, including alkyl, aryl, and heteroaryl sulfonates or carboxylates. As used herein, a “sulfonate” refers to the group —SO ₃ M ¹ , where M ¹ is H ⁺ or an alkali metal ion (e.g., Na ⁺ , Li ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ etc.); or ammonium (NH ₄ ⁺ )). As used herein, "carboxylate" refers to the group --CO ₂ M ¹ , where M ¹ is H ⁺ or an alkali metal ion (eg, Na ⁺ , Li ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ etc.); or ammonium (NH ₄ ⁺ )). Examples of sulfonate and carboxylate dopants are benzoate compounds, heptafluorobutyrate, methanesulfonate, trifluoromethanesulfonate, p-toluenesulfonate, pentafluoropropionate, and polymeric sulfonates, perfluorosulfonate-containing ionomers This includes, but is not limited to, the like.

In some embodiments, dopants do not include sulfonates or carboxylates.

In some embodiments, the dopant is a sulfonylimide (such as bis(trifluoromethanesulfonyl)imide); an antimonate (such as hexafluoroantimonate); an arsenate (such as hexafluoroarsenate); (eg, hexafluorophosphate, etc.); and borate (eg, tetrafluoroborate, tetraarylborate, trifluoroborate, etc.) excluding the component (B). Examples of tetraarylborates include, but are not limited to, halogenated tetraarylborates such as tetrakispentafluorophenylborate (TPFB). Examples of trifluoroborates are (2-nitrophenyl)trifluoroborate, benzofurazan-5-trifluoroborate, pyrimidine-5-trifluoroborate, pyridine-3-trifluoroborate, and 2,5-dimethylthiophene- Including but not limited to 3-trifluoroborate.

The dopant can be, for example, a material from which a doped polythiophene is produced, eg, by undergoing one or more electron transfer reactions, eg, with a conjugated polymer. The dopant can be selected to provide a suitable charge-balancing counteranion. Reactions can occur by mixing polythiophenes and dopants, as is known in the art. For example, the dopant can undergo spontaneous electron transfer from the polymer to a cation-anion dopant (such as a metal salt), leaving the conjugated polymer in its anion-associated oxidized form with the free metal. See, for example, Lebedev et al., Chem. Mater., 1998, 10, 156-163. As disclosed herein, polythiophene and dopant may refer to components that react to form a doped polymer. The doping reaction may be a charge transfer reaction in which charge carriers are generated, and this reaction may be reversible or irreversible. In some embodiments, silver ions can undergo electron transfer to or from silver metal and doped polymers.

In the final formulation, the composition may be distinct from the original combination of ingredients (i.e., the polythiophene and/or dopants may or may not be present in the final composition in the same form as before mixing). can be used).
Inorganic acids, organic acids, organic or inorganic oxidizing agents, and the like are used as dopants. As organic acids, polymeric organic acids and/or low-molecular-weight organic acids (non-polymeric organic acids) are used.
In one embodiment, the organic acid is a sulfonic acid and its salt (-SO ₃ M ² , where M ² is an alkali metal ion (eg, Na ⁺ , Li ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ etc. ), ammonium (NH ₄ ⁺ ), mono-, di-, and trialkylammonium (such as triethylammonium).Among the sulfonic acids, arylsulfonic acids are preferred.

_In some embodiments, specific examples of dopants include strong inorganic acids such as hydrogen chloride, sulfuric acid _, nitric acid, phosphoric acid; Boron bromide (BBr ₃ ), boron trifluoride etherate (BF ₃ OEt ₂ ), iron (III) chloride (FeCl ₃ ), copper (II) chloride (CuCl ₂ ), antimony (V) pentachloride (SbCl ₅ ), Lewis acids such as arsenic (V) pentafluoride (AsF ₅ ), phosphorus pentafluoride (PF ₅ ), tris(4-bromophenyl)aluminum hexachloroantimonate (TBPAH); polymeric organic compounds such as polystyrene sulfonic acid; acids; benzenesulfonic acid, tosylic acid, camphorsulfonic acid, hydroxybenzenesulfonic acid, 5-sulfosalicylic acid, dodecylbenzenesulfonic acid, 1,4-benzodioxanedisulfonic acid derivatives described in WO 2005/000832, Low-molecular-weight organic acids (non-polymeric organic acids) such as arylsulfonic acid derivatives described in WO 2006/025342 and dinonylnaphthalenesulfonic acid derivatives described in JP-A-2005-108828;7, Organic or inorganic oxidizing agents such as 7,8,8-tetracyanoquinodimethane (TCNQ), 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), iodine, heteropolyacid compounds, etc. can be, but are not limited to.

In some embodiments, the dopant includes at least one selected from the group consisting of an arylsulfonic acid compound, a heteropolyacid compound, and an ionic compound containing an element belonging to Group 13 or Group 15 of the long period periodic table. .
Particularly preferred dopants include polymeric organic acids such as polystyrenesulfonic acid, 5-sulfosalicylic acid, dodecylbenzenesulfonic acid, 1,4-benzodioxanedisulfonic acid derivatives described in WO 2005/000832, JP 2005 Low-molecular-weight organic acids (non-polymeric organic acids) such as dinonylnaphthalenesulfonic acid derivatives described in JP-108828 can be mentioned. Moreover, a sulfonic acid derivative represented by the following formula (2) can also be preferably used.

〔式中、Ｘ^１は、Ｏ、Ｓ又はＮＨを表し、Ａは、Ｘ^１及びｃ個の（ＳＯ_３Ｈ）基以外の置換基を有していてもよいナフタレン環又はアントラセン環を表し、Ｔは、非置換若しくは置換の炭化水素基、１，３，５－トリアジン基、又は非置換若しくは置換の下記式（３）若しくは（４）：

で示される基（式中、Ｗ^１及びＷ^２は、それぞれ独立して、Ｏ、Ｓ、Ｓ（Ｏ）基、Ｓ（Ｏ_２）基、又は非置換若しくは置換基が結合したＮ、Ｓｉ、Ｐ、Ｐ（Ｏ）基を示す。Ｗ^１は単結合でもよい。Ｒ^４６～Ｒ^５９はそれぞれ独立して水素原子又はハロゲン原子を表す。）を表し、ｃは、Ａに結合するスルホン酸基数を表し、１≦ｃ≦４を満たす整数であり、ｄは、ＴとＸ^１との結合数を示し、１≦ｄを満たす整数である。〕

[In the formula, X ¹ represents O, S or NH, A represents a naphthalene ring or anthracene ring optionally having substituents other than X ¹ and c (SO ₃ H) groups, T is an unsubstituted or substituted hydrocarbon group, a 1,3,5-triazine group, or an unsubstituted or substituted formula (3) or (4) below:

(wherein W ¹ and W ² are each independently an O, S, S(O) group, S(O ₂ ) group, or an unsubstituted or substituted N, Si, P, P(O) groups, W ¹ may be a single bond, R ⁴⁶ to R ⁵⁹ each independently represent a hydrogen atom or a halogen atom, and c is the number of sulfonic acid groups bonded to A is an integer that satisfies 1≤c≤4, d indicates the ^number of connections between T and X1, and is an integer that satisfies 1≤d. ]

R ⁴⁶ to R ⁵⁹ in formula (3) or (4) are preferably fluorine atoms, more preferably all fluorine atoms. W ¹ in formula (3) is preferably a single bond. Most preferably, W ¹ in formula (3) is a single bond and R ⁴⁶ to R ⁵³ are all fluorine atoms.

（式中、Ｘ^１は、Ｏ、Ｓ又はＮＨを表し、Ａｒ^５は、アリール基を表し、ｃは、スルホン酸基数を表し、１～４を満たす整数である。） As the arylsulfonic acid compound according to the present invention, one represented by the following formula (5) can also be used.

(In the formula, X ¹ represents O, S or NH, Ar ⁵ represents an aryl group, c represents the number of sulfonic acid groups, and is an integer satisfying 1 to 4.)

（式中、Ａｒ^５は、アリール基を表す。） In the formula (5), X ¹ represents O, S or NH, and O is particularly preferable because of its easy synthesis.
c represents the number of sulfonic acid groups bonded to the naphthalene ring and is an integer satisfying 1 to 4, but c = 1 or 2 is preferable in consideration of imparting high electron-accepting properties and high solubility to the compound. . Among them, a compound represented by the following formula (6) is suitable.

(wherein Ar ⁵ represents an aryl group.)

（式中、Ｒ^６０～Ｒ^６４は、互いに独立して、水素原子、ハロゲン原子、ニトロ基、炭素数１～１０のアルキル基、炭素数１～１０のハロゲン化アルキル基、炭素数２～１０のハロゲン化アルケニル基を示す。） Examples of the aryl group in formulas (5) and (6) include aryl groups such as phenyl, xylyl, tolyl, biphenyl, and naphthyl groups, and these aryl groups may have substituents. good.
Examples of the substituent include hydroxyl group, amino group, silanol group, thiol group, carboxyl group, phosphoric acid group, phosphoric acid ester group, ester group, thioester group, amide group, nitro group, cyano group, monovalent hydrocarbon group, Examples include, but are not limited to, organooxy groups, organoamino groups, organosilyl groups, organothio groups, acyl groups, sulfone groups, and halogen atoms.
Among these aryl groups, an aryl group represented by the following formula (7) is particularly preferably used.

(wherein R ⁶⁰ to R ⁶⁴ are each independently a hydrogen atom, a halogen atom, a nitro group, an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 10 carbon atoms, a represents a halogenated alkenyl group.)

（式中、Ｒ^６２は、水素原子、ハロゲン原子、ニトロ基、炭素数１～１０のアルキル基、炭素数１～１０のハロゲン化アルキル基、炭素数２～１０のハロゲン化アルケニル基を示す。） In the formula (7), the halogen atom may be any of chlorine, bromine, fluorine and iodine atoms, but in the present invention, the fluorine atom is particularly preferred.
Examples of alkyl groups having 1 to 10 carbon atoms include methyl group, ethyl group, n-propyl group, i-propyl group, n-butyl group, i-butyl group, t-butyl group, n-pentyl group and n-hexyl. group, n-heptyl group, n-octyl group, n-nonyl group, 2-ethylhexyl group, n-decyl group, cyclopentyl group, cyclohexyl group and the like.
Examples of halogenated alkyl groups having 1 to 10 carbon atoms include trifluoromethyl group, 2,2,2-trifluoroethyl group, 1,1,2,2,2-pentafluoroethyl group, 3,3,3- trifluoropropyl group, 2,2,3,3,3-pentafluoropropyl group, 1,1,2,2,3,3,3-heptafluoropropyl group, 4,4,4-trifluorobutyl group, 3,3,4,4,4-pentafluorobutyl group, 2,2,3,3,4,4,4-heptafluorobutyl group, 1,1,2,2,3,3,4,4, A 4-nonafluorobutyl group and the like can be mentioned.
Examples of the halogenated alkenyl group having 2 to 10 carbon atoms include perfluorovinyl group, perfluoropropenyl group (allyl group), perfluorobutenyl group and the like.
Among these, it is particularly preferable to use an aryl group represented by the following formula (8) in consideration of further increasing the solubility in organic solvents.

(In the formula, R ⁶² represents a hydrogen atom, a halogen atom, a nitro group, an alkyl group having 1 to 10 carbon atoms, a halogenated alkyl group having 1 to 10 carbon atoms, or a halogenated alkenyl group having 2 to 10 carbon atoms. )

In formula (8), R ⁶² is particularly preferably a halogenated alkyl group, a halogenated alkenyl group or a nitro group, more preferably a trifluoromethyl group, a perfluoropropenyl group or a nitro group.

（式中、Ｅは長周期型周期表の第１３族又は第１５族に属する元素を表し、Ａｒは、各々独立して、置換基を有してもよいアリール基又は置換基を有してもよいヘテロアリール基を表わす。） Furthermore, when (F) a matrix compound described later is added, an ionic compound composed of an anion represented by the following formula (a5) and its counter cation can also be suitably used as a dopant.

(Wherein, E represents an element belonging to Group 13 or Group 15 of the long period periodic table, and each Ar independently has an aryl group which may have a substituent or a substituent represents a good heteroaryl group.)

In formula (a5), E is preferably boron, gallium, phosphorus, or antimony among the elements belonging to group 13 or group 15 of the long period periodic table, and more preferably boron.

In formula (a5), examples of the aryl group and heteroaryl group include a monovalent group derived from a 5- or 6-membered monocyclic ring or 2 to 4 condensed rings. Among them, a monovalent group derived from a benzene ring, a naphthalene ring, a pyridine ring, a pyrazine ring, a pyridazine ring, a pyrimidine ring, a triazine ring, a quinoline ring, or an isoquinoline ring is preferred from the viewpoint of compound stability and heat resistance.
Furthermore, at least one group of Ar more preferably has one or more fluorine atoms or chlorine atoms as substituents. In particular, a perfluoroaryl group in which all hydrogen atoms of Ar are substituted with fluorine atoms is most preferred. Specific examples of perfluoroaryl groups include pentafluorophenyl, heptafluoro-2-naphthyl and tetrafluoro-4-pyridyl groups.

で示されるアニオンとカチオンの組合せであるイオン化合物（特許第５３８１９３１号を参照）を好適に用いることができる。 Among those mentioned above, the following formulas (10) and (11):

An ionic compound (see Japanese Patent No. 5381931) which is a combination of an anion and a cation represented by can be preferably used.

Heteropolyacid compounds are also particularly preferred as dopants. Heteropolyacid compounds typically have a structure in which a heteroatom is located at the center of the molecule, represented by a Keggin-type chemical structure represented by formula (A) or a Dawson-type chemical structure represented by formula (B), and vanadium ( V), molybdenum (Mo), tungsten (W), and other oxyacid isopolyacids are condensed with oxyacids of different elements. Oxygen acids of such dissimilar elements mainly include oxyacids of silicon (Si), phosphorus (P), and arsenic (As).

Specific examples of heteropolyacid compounds include phosphomolybdic acid, silicomolybdic acid, phosphotungstic acid, phosphotungstomolybdic acid, and silicotungstic acid. Phosphomolybdic acid, phosphotungstic acid, silicotungstic acid are preferred, and phosphotungstic acid is more preferred.
These heteropolyacid compounds may be synthesized by a known synthesis method and used, but they are also available as commercial products. For example, phosphotungstic acid hydrate (or 12-Tungstophosphoric acid n-hydrate, chemical formula: H ₃ (PW ₁₂ O ₄₀ )·nH ₂ O), phosphomolybdic acid hydrate (or 12-Molybdo (VI ) phosphoric acid n-hydrate, chemical formula: H ₃ (PMo ₁₂ O ₄₀ ) nH ₂ O (n≈30)) was manufactured by Kanto Chemical Co., Ltd., Wako Pure Chemical Industries, Ltd., Sigma-Aldrich Japan Co., Ltd., Japan It is available from manufacturers such as Inorganic Chemical Industry Co., Ltd. and Japan New Metals Co., Ltd.

In some embodiments, reaction by-products may be removed from the doping process. For example, metals such as silver can be removed by filtration.

For example, the material can be purified to remove halogens and metals. Halogen includes, for example, chloride, bromide and iodide. Metals include, for example, dopant cations (including reduced forms of dopant cations), or metals left over from catalyst or initiator residues. Metals include, for example, silver, nickel, and magnesium. The amount may be, for example, less than 100 ppm, or less than 10 ppm, or less than 1 ppm.

Metal content, including silver content, can be determined by ICP-MS, especially at concentrations above 50 ppm.

In some embodiments, when the polythiophene is doped with a dopant comprising component (B), the doped polymer composition is formed by mixing the polythiophene and the dopant. Mixing can be accomplished using any method known to those skilled in the art. For example, a solution containing polythiophene can be mixed with another solution containing a dopant. The solvent used for dissolving the polythiophene and the dopant is one or more organic solvents that constitute (C) the liquid carrier described below. Reactions can occur by mixing polythiophenes and dopants, as is known in the art. The resulting doped polythiophene composition contains about 40% to 75% polymer and about 25% to 55% dopant, by weight based on the composition. In another embodiment, the doped polythiophene composition comprises from about 50% to 65% polythiophene and from about 35% to 50% dopant, by weight based on the composition. Typically, the polythiophene weight is greater than the dopant weight. Typically, the dopant may be a silver salt such as silver tetrakis(pentafluorophenyl)borate in an amount of about 0.25-0.5 m/ru (where m is the mole of silver salt). and ru is the molar amount of polymer repeat units).

The doped polythiophene is isolated by methods known to those skilled in the art (eg, by rotary evaporation of the solvent, etc.) to give a dry or substantially dry material (such as a powder). The amount of residual solvent may be, for example, 10% or less, or 5% or less, or 1% or less, by weight based on dry or substantially dry material. A dry or substantially dry powder can be redispersed or redissolved in one or more fresh solvents.

[(C) Component]
Component (C) is a liquid carrier containing an organic solvent. Component (C) is a component necessary to dissolve components (A) and (B) well and to uniformly mix components (A) and (B) to form an ink composition. . As component (C), component (A) and/or component (B) are partially solubilized or It may contain an organic solvent for swelling. In addition, component (C) may further contain one or more organic solvents that act as non-solvents for component (A).

Component (C) may be used alone or in combination of two or more. Component (C) may be a solvent mixture comprising two or more organic solvents adapted for use and processing with other layers in the device, such as the anode or emissive layer. Organic solvents may also be used in component (C) in varying proportions to improve ink properties such as substrate wettability, ease of solvent removal, viscosity, surface tension and jettability. can.

(C) Component, for example, can be exemplified by "glycol-based solvent (s1)". “Glycol-based solvent” means a solvent of the formula R ^h —O—(R ^g —O) _n —R ⁱ , where each R ^g is independently a linear or branched C ₂ -C ₄ a substituted alkylene group, wherein R ^h and R ⁱ are each independently a hydrogen atom, a linear, branched or cyclic C ₁ -C ₈ unsubstituted alkyl group or a linear or branched C ₁ -C ₈ non is a substituted aliphatic acyl group, n is an integer of 1 to 6), one or more organic solvents having no aromatic structure, glycol monoethers; glycol diethers glycol ester ethers; glycol monoesters; glycol diesters; and glycols. It is particularly preferred that said ^Rg is a _C2 or _C3 unsubstituted alkylene group. Further, n is particularly preferably an integer of 1-4. The alkyl group is preferably a linear, branched or cyclic C ₁ -C ₆ unsubstituted alkyl group, more preferably a linear C ₁ -C ₄ unsubstituted alkyl group, a methyl group and an n-butyl group. Especially preferred. The acyl group is preferably a linear or branched C ₂ -C ₆ unsubstituted aliphatic acyl group, more preferably a linear C ₂ -C ₄ unsubstituted acyl group, and particularly preferably an acetyl group and a propionyl group. .

Component (s1) in component (C) includes, for example, the following solvents.
・Glycols that are ethylene glycol, propylene glycol or oligomers thereof (dimer to tetramer, such as diethylene glycol) ・Glycol monoethers that are monoalkyl ethers of the above glycols ・Dialkyl ethers of the above glycols Glycol diethers that are aliphatic carboxylic acid monoesters of the above glycols Glycol diesters that are aliphatic carboxylic acid diesters of the above glycols Aliphatic carboxylic acid monoesters of the above glycol monoethers Glycol ester ethers that are esters

Among these, the component (C) contains at least one selected from the group consisting of glycol monoethers, glycol diethers and glycols, and the total of the glycol monoethers, glycol diethers and glycols When the content is more than 50% by weight based on the total weight of the component (C), the solubility of the solid content of the ink can be maintained during film formation by inkjet coating, and the ink composition can maintain the solubility (E ) When metal oxide nanoparticles are contained, aggregation of the component (E) can be appropriately controlled to form a flatter film, which is preferable. The total content of glycol monoethers, glycol diethers and glycols is more preferably 60% by weight or more, still more preferably 75% by weight or more, particularly preferably 75% by weight or more, based on the total weight of component (C). is 90% by weight or more. The upper limit of the content ratio of glycol monoethers, glycol diethers and glycols is 100% by weight.

The component (s1) in the component (C) may be mixed. Examples include, but are not limited to, mixing glycol diethers and glycols. Specific examples thereof include specific examples of glycol diethers and glycols, which will be described later. Preferably, the glycol diethers are triethylene glycol dimethyl ether and triethylene glycol butyl methyl ether, and the glycols are ethylene glycol, Diethylene glycol is mentioned.

Examples of glycol monoethers include alkylene glycol monoethers (glycol monoethers). Examples of suitable glycol monoethers include, but are not limited to, ethylene glycol monopropyl ether, ethylene glycol monohexyl ether (hexylcellosolve), propylene glycol monobutyl ether (Dowanol™ PnB), diethylene glycol monoethyl ether (ethylcarbitol ), dipropylene glycol n-butyl ether (Dowanol™ DPnB), ethylene glycol monobutyl ether (butyl cellosolve), diethylene glycol monobutyl ether (butyl carbitol), dipropylene glycol monomethyl ether (Dowanol™ DPM), propylene glycol monopropyl ether (Dowanol™ PnP), diethylene glycol monopropyl ether (propyl carbitol), diethylene glycol monohexyl ether (hexyl carbitol), 2-ethylhexyl carbitol, dipropylene glycol monopropyl ether (Dowanol™ DPnP), tri Propylene glycol monomethyl ether (Dowanol™ TPM), diethylene glycol monomethyl ether (methyl carbitol) and tripropylene glycol monobutyl ether (Dowanol™ TPnB).

Examples of glycol diethers include, for example, ethylene glycol diethers (1,2-dimethoxyethane, 1,2-diethoxyethane and 1,2-dibutoxyethane, etc.); diethylene glycol diethers (diethylene glycol dimethyl ether and diethylene glycol diethyl ether etc.); propylene glycol diethers (such as propylene glycol dimethyl ether, propylene glycol diethyl ether and propylene glycol dibutyl ether); dipropylene glycol diethers (such as dipropylene glycol dimethyl ether, dipropylene glycol diethyl ether and dipropylene glycol dibutyl ether); Higher analogues of ethylene glycol and propylene glycol ethers referred to herein (i.e., tri- and tetra-analogs such as triethylene glycol dimethyl ether, triethylene glycol butyl methyl ether, tetraethylene glycol dimethyl ether, etc.) )including.

Examples of glycols include ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, triethylene glycol, tripropylene glycol and the like.

Component (s1) in component (C) may further include ethylene glycol monoether acetate and propylene glycol monoether acetate (glycol ester ethers), where ethers are, for example, methyl, ethyl , n-propyl, iso-propyl, n-butyl, sec-butyl, tert-butyl and cyclohexyl. It also includes the higher glycol ether analogues (di-, tri- and tetra-, etc.) listed above.
Examples include, but are not limited to, propylene glycol methyl ether acetate, 2-ethoxyethyl acetate, 2-butoxyethyl acetate, ethylene glycol monomethyl ether acetate, diethylene glycol monomethyl ether acetate.

Component (s1) in component (C) can further include ethylene glycol diacetate and the like (glycol diesters), and higher order glycol ether analogues (di-, tri- and tetra- etc.).
Examples include, but are not limited to, ethylene glycol diacetate, triethylene glycol diacetate, propylene glycol diacetate.

The (C) component can further consider an organic solvent (s2) excluding glycol-based solvents. The (s2) component may be used alone or in combination of two or more. Component (s2) is, for example, aliphatic and aromatic ketones, organic sulfur solvents such as dimethylsulfoxide (DMSO) and 2,3,4,5-tetrahydrothiophene-1,1-dioxide (tetramethylene sulfone; sulfolane) ; tetrahydrofuran (THF), tetrahydropyran (THP), tetramethylurea (TMU), N,N'-dimethylpropylene urea; aromatic hydrocarbons such as alkylated benzenes (xylene and its isomers, etc.), halogenated Benzenes, N-methylpyrrolidinone (NMP), dimethylformamide (DMF), dimethylacetamide (DMAc), dichloromethane, dioxanes, ethyl acetate, ethyl benzoate, methyl benzoate, dimethyl carbonate, ethylene carbonate, propylene carbonate; acetonitrile, Nitriles such as 3-methoxypropionitrile and 3-ethoxypropionitrile; aromatic ethers such as anisole, ethoxybenzene and dimethoxybenzene; methanol, ethanol, trifluoroethanol, n-propanol, isopropanol, n-butanol , t-butanol, 2-ethylhexyl alcohol, 2-(benzyloxy)ethanol, diisobutylcarbinol, methylisobutylcarbinol, or combinations thereof.

Component (s2) is preferably nitriles, alcohols, aromatic ethers or aromatic hydrocarbons.
Examples include, but are not limited to, nitriles such as methoxypropionitrile, ethoxypropionitrile, alcohols such as benzyl alcohol, 2-(benzyloxy)ethanol, aromatic ethers such as methylanisole, dimethylanisole, ethylanisole. , butylphenyl ether, butylanisole, pentylanisole, hexylanisole, heptylanisole, octylanisole, phenoxytoluene, aromatic hydrocarbons such as pentylbenzene, hexylbenzene, heptylbenzene, octylbenzene, nonylbenzene, cyclohexylbenzene or tetralin. mentioned.
Among these, alcohols are more preferable, and 2-(benzyloxy)ethanol is more preferable among alcohols.

Other examples of the (s2) component include aliphatic and aromatic ketones. Aliphatic and aromatic ketones are acetone, acetonylacetone, methylethylketone (MEK), methylisobutylketone, methylisobutenylketone, 2-hexanone, 2-pentanone, acetophenone, ethylphenylketone, cyclohexanone, and cyclopentanone. including but not limited to. In some embodiments, ketones with protons on carbons alpha to the ketone are avoided, such as cyclohexanone, methyl ethyl ketone, and acetone.

In some embodiments, the use of aprotic non-polar solvents can provide the added benefit of extending the lifetime of devices with emitter technology that is sensitive to protons (eg, PHOLEDs, etc.).

In some embodiments, component (C) comprises dimethylsulfoxide, ethylene glycol (glycols), tetramethylurea, or mixtures thereof.
Examples of suitable glycols include, but are not limited to, ethylene glycol, diethylene glycol, dipropylene glycol, polypropylene glycol, propylene glycol, triethylene glycol, and the like.

When the component (C) contains the component (s1) and the component (s2), the content of the component (s1): wts1 (weight) and the content of the component (s2): wts2 (weight) are expressed by the formula ( 1-1) is preferably satisfied, formula (1-2) is more preferably satisfied, and formula (1-3) is most preferably satisfied.
0.05≦wts2/(wts1+wts2)≦0.50 (1-1)
0.10≦wts2/(wts1+wts2)≦0.40 (1-2)
0.15≦wts2/(wts1+wts2)≦0.30 (1-3)
When two or more components (s1) are contained, wts1 indicates the total content (weight) of the components (s1), and when two or more components (s2) are contained, wts2 is (s2 ) indicates the total content (weight) of the components.
In one aspect, when the content of the component (s1) and the component (s2) satisfies the above relationship, aggregation of the component (E) can be more appropriately controlled during film formation by inkjet coating, forming a flatter film. preferred because it can

The amount of component (C) is about 50% to about 99% by weight, typically about 75% to about 98% by weight, more typically about 90% by weight, based on the total amount of the ink composition. to about 95% by weight.

[(D) component]
The ink composition may further contain (D) an amine compound. By adding the component (D), the dispersibility of the component (A) in the component (C) can be improved. Component (D) includes, but is not limited to, ethanolamine compounds and alkylamine compounds. Component (D) may be used alone or in combination of two or more.

Examples of suitable ethanolamine compounds are dimethylethanolamine [(CH ₃ ) ₂ NCH ₂ CH ₂ OH], triethanolamine [N(CH ₂ CH ₂ OH) ₃ ], and N-tert-butyldiethanolamine [t- _{C4H9N ( CH2CH2OH} ) _{2 ]} .

Alkylamine compounds include primary, secondary, and tertiary alkylamine compounds. Examples of primary alkylamine compounds include, for example, ethylamine [C ₂ H ₅ NH ₂ ], n-butylamine [C ₄ H ₉ NH ₂ ], t-butylamine [C ₄ H ₉ NH ₂ ], 2-ethylhexylamine , n-hexylamine [C ₆ H ₁₃ NH ₂ ], n-decylamine [C ₁₀ H ₂₁ NH ₂ ], and ethylenediamine [H ₂ NCH ₂ CH ₂ NH ₂ ]. Secondary alkylamine compounds include, for example, diethylamine [(C ₂ H ₅ ) ₂ NH], di(n-propylamine) [(nC ₃ H ₉ ) ₂ NH], di(isopropylamine) [(i —C ₃ H ₉ ) ₂ NH], and dimethylethylenediamine [CH ₃ NHCH ₂ CH ₂ NHCH ₃ ]. Tertiary alkylamine compounds include, for example, trimethylamine [(CH ₃ ) ₃ N], triethylamine [(C ₂ H ₅ ) ₃ N], tri(n-butyl)amine [(C ₄ H ₉ ) ₃ N], and tetramethylethylenediamine [ _{( CH3} ) _{2NCH2CH2N ( CH3} ) ₂ ].

It is preferable from the viewpoint of solubility or dispersibility that component (D) contains (D1) a tertiary alkylamine compound and (D2) an amine compound other than the tertiary alkylamine compound.

Component (D1) is used to enhance the solubility or dispersibility of component (A). It is preferable to pretreat component (A) with component (D1) before manufacturing the ink composition, because the solubility or dispersibility of component (A) in component (C) is enhanced. When the ink composition of the present application is a non-aqueous ink composition, the component (A) is usually obtained as an aqueous dispersion. It is dissolved or dispersed to form an ink composition. In this case, if the component (D1) is added to the aqueous dispersion of the component (A), mixed and then dried, the solubility and dispersibility of the component (A) in the component (C) are improved. ,preferable. The component (D1) is preferably triethylamine.

Component (D2) is preferably a primary alkylamine compound. When the primary alkylamine compound is at least one selected from the group consisting of ethylamine, n-butylamine, t-butylamine, 2-ethylhexylamine, n-hexylamine, n-decylamine and ethylenediamine, (A ) is preferred from the viewpoint of the solubility or dispersibility of the components. Component (D2) is more preferably n-butylamine or 2-ethylhexylamine, and particularly preferably n-butylamine.

The amount of component (D) can be adjusted and measured as a weight percentage relative to the total amount of the ink composition. In some embodiments, the amount of component (D) is at least 0.01 wt%, at least 0.10 wt%, at least 1.00 wt%, at least 1.50 wt%, based on the total weight of the ink composition, or at least 2.00% by weight. In some embodiments, the amount of component (D) is from about 0.01 wt% to about 2.00 wt%, typically from about 0.05 wt% to about 1.50 wt%, based on the total weight of the ink composition. % by weight, more typically from about 0.1% to about 1.00% by weight. When sulfonated polythiophene is used as component (A), at least part of component (D) exists in the form of an ammonium salt, such as a trialkylammonium salt (sulfonated polythiopheneamine adduct) with the sulfonated conjugated polymer. may

The ratio of the component (D1) and the component (D2) is not particularly limited, but the amount (mole) ratio of the substances (D2): component (D1) can be set to 3:1 to 15:1, Preferably it is from 5:1 to 10:1.

[(E) component]
The ink composition may further comprise (E) metal oxide nanoparticles. By including the component (E) in the ink composition, the transparency of the charge-transporting thin film obtained using the ink composition can be increased and the absorbance in the visible spectrum can be decreased. As a result, it is possible to improve the current efficiency, the external quantum efficiency and the luminance half-life of the organic EL device produced using the charge-transporting thin film. The component (E) may be used alone or in combination of two or more.

As used herein, the term "metalloid" refers to an element having chemical and/or physical properties intermediate or a mixture of those of metals and non-metals. As used herein, the term "metalloid" refers to boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), and tellurium (Te).
As used herein, "metal oxide" includes tin (Sn), titanium (Ti), aluminum (Al), zirconium (Zr), zinc (Zn), niobium (Nb), tantalum (Ta) and W ( Tungsten) and other metals, and oxides of one or a combination of two or more of the above semimetals.

As used herein, the term "nanoparticle" refers to a nanoscale particle whose primary particle number average diameter is typically less than or equal to 500 nm. For the average diameter of primary particles, for example, transmission electron microscopy (TEM) or a method of converting from specific surface area by BET method, or the like can be used.

In the TEM particle size measurement method, an image processing software is used to process the projected image of the nanoparticles and then determine the area equivalent diameter (which is defined as the diameter of a circle with the same area as the nanoparticles). method can measure the particle size. Typically, the projection image is obtained using image processing software provided with a TEM (e.g., a transmission electron microscope HT7700 (available from Hitachi High-Technologies Co., Ltd.)) created by the manufacturer of the TEM. process. The average particle size can be determined as the number average of equivalent circle diameters.

The number average particle size of the primary particles of component (E) is 500 nm or less; 250 nm or less; 100 nm or less; or 50 nm or less; or 25 nm or less. Typically, component (E) has a number average particle size of about 1 nm to about 100 nm, more typically about 2 nm to about 30 nm.

Metal oxides include boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), tin (Sn), titanium (Ti), and aluminum (Al). , zirconium (Zr), zinc (Zn), niobium (Nb), tantalum (Ta) and W (tungsten), or mixed oxides containing these. Specific non _- limiting examples of suitable metal oxide nanoparticles _{are B2O3} , _B2O , _SiO2 , SiO, _GeO2 , _GeO , _As2O4 , _{As2O3 , As2O5} , Sb ₂ O ₃ , Sb ₂ O ₅ , TeO ₂ , SnO ₂ , ZrO ₂ , Al ₂ O ₃ , ZnO and mixtures thereof.

_In some embodiments, the ink composition _comprises B2O3 _{, B2O} , _SiO2 , SiO, _GeO2 , GeO, _As2O4 , _{As2O3 , As2O5} , _SnO2 , _SnO , Sb ₂ O ₃ , TeO ₂ , or mixtures thereof, comprising one or more metal oxide nanoparticles.

In some embodiments, the ink composition comprises one or more metal oxide nanoparticles comprising _SiO2 . When the component (E) is metal oxide nanoparticles containing SiO ₂ , the charge-transporting thin film obtained using the ink composition can have higher transparency and lower absorbance in the visible spectrum, It is preferable because the current efficiency, the external quantum efficiency and the luminance half-life of the organic EL element manufactured using the charge-transporting thin film can be further improved.

The metal oxide nanoparticles may contain one or more organic capping groups. Such organic capping groups may be reactive or non-reactive. A reactive organic capping group is an organic capping group that can be crosslinked, for example, in the presence of UV radiation or a radical initiator.

In some embodiments, the metal oxide nanoparticles comprise one or more organic capping groups.

Examples of suitable metal oxide nanoparticles are those sold as ORGANOSILICASOL™ by Nissan Chemical Industries, Ltd. in various solvents such as methyl ethyl ketone, methyl isobutyl ketone, dimethylacetamide, ethylene glycol, isopropanol, methanol, _SiO2 nanoparticles available as dispersions in ethylene glycol monopropyl ether, and propylene glycol monomethyl ether acetate, etc.).

The amount of component (E) in the ink composition can be adjusted and measured as a weight percentage relative to the combined weight of components (A) and (B) and any of components (D)-(F). In some embodiments, the amount of component (E) is from 1% to 98% by weight, based on the combined weight of components (A) and (B) and any of components (D)-(F), typically about 2% to about 95%, more typically about 5% to about 90%, even more typically about 10% to about 90% by weight. In some embodiments, the amount of component (E) is from about 20% to about 98% by weight, based on the combined weight of components (A) and (B) and any of components (D)-(F), Typically from about 25% to about 95% by weight.

[(F) component]
The ink composition may further comprise one or more (F) matrix compounds known to be useful in hole injection layers (HIL) or hole transport layers (HTL). Component (F) is a compound capable of improving the build-up during thin film production and making the thickness uniform and flat. In an organic EL device having a charge-transporting thin film produced using an ink composition that further contains the component (F), the thickness uniformity of the light-emitting layer, etc. formed on the upper layer side of the charge-transporting thin film is also improved. Therefore, it is possible to improve the device characteristics without unevenness in light emission. Component (F) may be used alone or in combination of two or more.

Component (F) may be a low molecular weight or high molecular weight compound and is different from the polythiophenes described herein. A matrix compound may be, for example, a synthetic polymer. See, for example, US Patent Publication No. 2006/0175582, published Aug. 10, 2006. Synthetic polymers can include, for example, carbon backbones. In some embodiments, the synthetic polymer has at least one pendant polymer group containing an oxygen atom or a nitrogen atom. The synthetic polymer may be a Lewis base. Typically, synthetic polymers contain a carbon backbone and have a glass transition temperature above 25°C. The synthetic polymer may also be a semi-crystalline or crystalline polymer having a glass transition temperature below 25°C and/or a melting point above 25°C. The synthetic polymer may contain one or more acid groups, such as sulfonic acid groups.

In one embodiment, the synthetic polymer, component (F), has at least one alkyl or alkoxy group substituted by at least one fluorine atom and at least one sulfonic acid (—SO ₃ H) residue. is a polymeric acid comprising one or more repeat units comprising an alkyl or alkoxy group optionally interrupted by at least one ether-linked (--O--) group.

［式中、各々のＲ_５、Ｒ_６、Ｒ_７、Ｒ_８、Ｒ_９、Ｒ_１０、及びＲ_１１は、独立に、Ｈ、ハロゲン、フルオロアルキル、又はペルフルオロアルキルであり；そしてＸは、－［ＯＣ（Ｒ_ｊＲ_ｋ）－Ｃ（Ｒ_ｌＲ_ｍ）］_ｒ－Ｏ－［ＣＲ_ｎＲ_ｏ］_ｚ－ＳＯ_３Ｈであって、各々のＲ_ｊ、Ｒ_ｋ、Ｒ_ｌ、Ｒ_ｍ、Ｒ_ｎ及びＲ_ｏは、独立に、Ｈ、ハロゲン、フルオロアルキル、又はペルフルオロアルキルであり；ｒは、０～１０であり；そしてｚは、１～５である］を含む。 In certain embodiments, the polymeric acid comprises repeat units according to formula (II) and repeat units according to formula (III):

[wherein each R ₅ , R ₆ , R ₇ , R ₈ , R ₉ , R ₁₀ , and R ₁₁ is independently H, halogen, fluoroalkyl, or perfluoroalkyl; and X is - [OC(R _j R _k )-C(R _l R _m )] _r —O-[CR _n R _o ] _z —SO ₃ H wherein each of R _j , R _k , R _l , R _m , R _n and R _o are independently H, halogen, fluoroalkyl, or perfluoroalkyl; r is 0-10; and z is 1-5.

_In some embodiments, each R5, _R6 , _R7 , and _R8 is independently Cl or F. In some embodiments, each R ₅ , R ₇ and R ₈ is F and R ₆ is Cl. In some embodiments, each R ₅ , R ₆ , R ₇ , and R ₈ is F.

In some embodiments, each R ₉ , R ₁₀ , and R ₁₁ is F.

In some embodiments, each R _j , R _k , R _l , R _m , R _n and R _o is independently F, (C ₁ -C ₈ )fluoroalkyl, or (C ₁ -C ₈ )perfluoro is alkyl.

In certain embodiments, each R _n and R _o is F; r is 0;

_In certain embodiments, each R5, _R7 , and _R8 is F and _R6 is Cl; and each _Rn and _R0 is F; Yes; and z is two.

and each R _n and R _{o is F ; r} is 0; and z is 2.

The ratio of the number of repeating units according to formula (II) (“n1”) to the number of repeating units according to formula (III) (“n2”) is not particularly limited. The n1:n2 ratio is typically 9:1 to 1:9, more typically 8:2 to 2:8. In some embodiments, the n1:n2 ratio is 9:1. In one embodiment, the n1:n2 ratio is 8:2.

Polymeric acids suitable for use in the present disclosure are synthesized using methods known to those skilled in the art or obtained from commercial sources. For example, a polymer comprising repeat units according to formula (II) and repeat units according to formula (III) can be obtained by combining a monomer represented by formula (IIa) with a monomer represented by formula (IIIa):

［式中、Ｒ_５～Ｒ_１１は、上記と同義であり、Ｚ_１は、－［ＯＣ（Ｒ_ｊＲ_ｋ）－Ｃ（Ｒ_ｌＲ_ｍ）］_ｒ－Ｏ－［ＣＲ_ｎＲ_ｏ］_ｚ－ＳＯ_２Ｆであって、Ｒ_ｊ、Ｒ_ｋ、Ｒ_ｌ、Ｒ_ｍ、Ｒ_ｎ及びＲ_ｏ、ｒ、及びｚは、本明細書中と同義である］と、公知の重合方法により共重合し、続いてスルホニルフルオリド基の加水分解によりスルホン酸基に変換することによって製造されうる。

[Wherein, R ₅ to R ₁₁ are as defined above, and Z ₁ is -[OC(R _j R _k )-C(R _l R _m )] _r -O-[CR _n R _o ] _z —SO ₂ F, wherein R _j , R _k , R _l , R _m , R _n and R _o , r, and z have the same meanings as defined herein] and copolymerization by a known polymerization method. and subsequent hydrolysis of the sulfonyl fluoride group to convert it to a sulfonic acid group.

For example, tetrafluoroethylene (TFE) or chlorotrifluoroethylene (CTFE) can be added to one or more fluorinated monomers (eg, F ₂ C═CF—O—CF ₂ —CF ₂ — containing precursor groups of sulfonic acid). SO ₂ F; F ₂ C═CF—[O—CF ₂ —CR _p F—O] _q1 —CF ₂ —CF ₂ —SO ₂ F, where R _p is F or CF ₃ and q1 is 1 to 10); F ₂ C=CF-O-CF ₂ -CF ₂ -CF ₂ -SO ₂ F; and F ₂ C=CF-OCF ₂ -CF ₂ -CF ₂ -CF ₂ -SO ₂ F, etc.).

The equivalent weight of a polymeric acid is defined as the mass (grams) of polymeric acid per mole of acid groups present in the polymeric acid. The equivalent weight of the polymeric acid is from about 400 to about 15,000 g polymer/mol acid, typically from about 500 to about 10,000 g polymer/mol acid, more typically from about 500 to 8,000 g polymer/mol acid, Even more typically about 500 to 2,000 g polymer/mol acid, even more typically about 600 to about 1,700 g polymer/mol acid.

Such polymeric acids are, for example, those sold under the trade name NAFION® by E.I. DuPont, those sold under the trade name AQUIVION® by Solvay Specialty Polymers, or AGC It is sold under the trade name FLEMION® by the Corporation.

In one embodiment, the synthetic polymer, component (F), is a polyethersulfone comprising one or more repeating units comprising at least one sulfonic acid (--SO ₃ H) residue.

に従う繰り返し単位、並びに式（Ｖ）に従う繰り返し単位及び式（VI）に従う繰り返し単位：

［式中、Ｒ_１２～Ｒ_２０は、それぞれ独立に、Ｈ、ハロゲン、アルキル、又はＳＯ_３Ｈであるが、ただし、Ｒ_１２～Ｒ_２０の少なくとも１個は、ＳＯ_３Ｈであり；そしてＲ_２１～Ｒ_２８は、それぞれ独立に、Ｈ、ハロゲン、アルキル、又はＳＯ_３Ｈであるが、ただし、Ｒ_２１～Ｒ_２８の少なくとも１個は、ＳＯ_３Ｈであり、そしてＲ_２９及びＲ_３０は、それぞれＨ又はアルキルである］からなる群より選択される繰り返し単位を含む。 In some embodiments, the polyethersulfone has the formula (IV):

and repeat units according to formula (V) and repeat units according to formula (VI):

[wherein R ₁₂ to R ₂₀ are each independently H, halogen, alkyl, or SO ₃ H, with the proviso that at least one of R ₁₂ to R ₂₀ is SO ₃ H; ₂₁ to R ₂₈ are each independently H, halogen, alkyl, or SO ₃ H, provided that at least one of R ₂₁ to R ₂₈ is SO ₃ H, and R ₂₉ and R ₃₀ are , each being H or alkyl].

In some embodiments, R ₂₉ and R ₃₀ are each alkyl. In some embodiments, R ₂₉ and R ₃₀ are each methyl.

In some embodiments, R ₁₂ -R ₁₇ , R ₁₉ , and R ₂₀ are each H and R ₁₈ is SO ₃ H.

In some embodiments, R ₂₁ -R ₂₅ , R ₂₇ and R ₂₈ are each H and R ₂₆ is SO ₃ H.

［式中、ａは、０．７～０．９であり、そしてｂは、０．１～０．３である］により表される。 In some embodiments, the polyethersulfone has the formula (VII):

where a is from 0.7 to 0.9 and b is from 0.1 to 0.3.

The polyethersulfone may further contain other repeat units, which may or may not be sulfonated.

［式中、Ｒ_３１及びＲ_３２は、それぞれ独立に、Ｈ又はアルキルである］で示される繰り返し単位を含んでもよい。 For example, polyethersulfone has the formula (VIII):

[wherein R ₃₁ and R ₃₂ are each independently H or alkyl].

に従う繰り返し単位を与えうる。 Any two or more repeat units described herein can be taken together to form a repeat unit, and the polyethersulfone may include such repeat units. For example, repeating units according to formula (IV) are combined with repeating units according to formula (VI) to give formula (IX):

can provide repeat units according to

に従う繰り返し単位を与えうる。 Similarly, for example, repeating units according to formula (IV) are combined with repeating units according to formula (VIII) to give formula (X):

can provide repeat units according to

［式中、ａは、０．７～０．９であり、そしてｂは、０．１～０．３である］により表される。 In some embodiments, the polyethersulfone has the formula (XI):

where a is from 0.7 to 0.9 and b is from 0.1 to 0.3.

Polyethersulfones containing one or more repeating units containing at least one sulfonic acid (—SO ₃ H) residue are commercially available; - Marketed as PES.

で示される繰り返し単位を含む、ビニル芳香族重合体である。式中、Ａｒ’は、置換されていてもよい芳香環であり、２種類以上でもよい。Ａｒ’としては置換されていてもよいフェニル基、置換されていてもよいナフチル基等が挙げられる。 In one aspect, the synthetic polymer, component (F), has the following formula (XII):

It is a vinyl aromatic polymer containing a repeating unit represented by. In the formula, Ar' is an optionally substituted aromatic ring, and may be of two or more kinds. Ar' includes an optionally substituted phenyl group, an optionally substituted naphthyl group, and the like.

In one aspect, the synthetic polymer that is component (F) is a vinyl aromatic polymer (e.g., poly(styrene) or a derivative thereof (excluding polystyrene sulfonic acid)); poly(vinyl acetate) or a derivative thereof; (ethylene-co-vinyl acetate) or derivatives thereof; poly(pyrrolidone) or derivatives thereof (e.g. poly(1-vinylpyrrolidone-co-vinyl acetate)); poly(vinylpyridine) or derivatives thereof; poly(methyl methacrylate) ) or derivatives thereof; poly(butyl acrylate) or derivatives thereof; poly(aryletherketone) or derivatives thereof; poly(arylsulfone) or derivatives thereof; poly(esters) or derivatives thereof; Including polymers or oligomers. These polymers or oligomers are preferable in terms of improving build-up during thin film production.

Among them, it is preferable that the component (F) is a vinyl aromatic polymer or a derivative thereof, since the build-up during the production of a thin film is further improved. More preferred are homopolymers or copolymers synthesized from one or more substituted or unsubstituted styrenes or derivatives thereof, and particularly preferred are copolymers synthesized from at least styrene and 4-hydroxystyrene or derivatives thereof. Furthermore, the use of a vinyl aromatic polymer or derivative thereof as the component (F) is preferable because the transparency of the charge-transporting thin film obtained from the ink composition can be increased and the absorbance in the visible spectrum can be easily decreased. As a result, it is possible to improve the current efficiency, the external quantum efficiency and the luminance half-life of the organic EL device produced using the charge-transporting thin film.

The vinyl aromatic polymer or derivative thereof is a copolymer or homopolymer which may contain a monomer component forming a repeating unit other than the repeating unit represented by formula (XII), and the ratio of formula (XII) to the total monomer components is A copolymer or homopolymer in which the ratio of monomers forming the indicated repeating unit is 50% by weight or more. The ratio of the monomer forming the repeating unit represented by formula (XII) to the entire monomer component is preferably 70% by weight or more, more preferably 80% by weight or more, and in one embodiment, 100%.

The matrix compound as component (F) may be composed of, for example, at least one semiconductor matrix compound component. This semiconductor matrix compound component is different from the (A) component described herein. The semiconducting matrix compound component may be a semiconducting small molecule or semiconducting polymer, typically composed of repeating units containing hole-carrying units in the backbone and/or side chains. The semiconductor matrix compound component may be in neutral form or doped and is typically an organic solvent (e.g. toluene, chloroform, acetonitrile, cyclohexanone, anisole, chlorobenzene, o-dichlorobenzene, benzoic acid ethyl and mixtures thereof).

In certain embodiments, it may be preferable not to mix the fluorinated polymeric acid and other matrix compounds from the standpoint of film-forming properties.

The amount of component (F) in the ink composition should be 5% to 95% by weight based on the combined weight of components (A) and (B) and optional components (D) to (F). is preferred, more preferably 50% to 90% by weight, particularly preferably 60% to 80% by weight. When the amount of component (F) is within the above range, the build-up can be further improved.

［式中、Ｒ_１及びＲ_２は、それぞれ独立に、Ｈ、アルキル、フルオロアルキル、アルコキシ、フルオロアルコキシ、アリールオキシ、－ＳＯ_３Ｍ、又は－Ｏ－［Ｚ－Ｏ］_ｐ－Ｒ_ｅであるか、あるいは、Ｒ_１及びＲ_２は、一緒になって－Ｏ－Ｚ－Ｏ－を形成する
（式中、Ｍは、Ｈ、アルカリ金属、アンモニウム、モノアルキルアンモニウム、ジアルキルアンモニウム、又はトリアルキルアンモニウムであり、Ｚは、場合によりハロゲン又はＹで置換されているヒドロカルビレン基（ここで、Ｙは、炭素数１～１０の直鎖又は分岐鎖のアルキル基又はアルコキシアルキル基であり、該アルキル基又はアルコキシアルキル基は、任意の位置がスルホン酸基で置換されていてもよい）であり、ｐは、１以上の整数であり、そして、Ｒ_ｅは、Ｈ、アルキル、フルオロアルキル、又はアリールである）］で表される繰り返し単位を含むポリチオフェン；
（Ｂ）オニウムボレート塩であって、式（ａ１）：

で表されるアニオン、式（ａ２）：

で表される１価又は２価のアニオン、及び（ａ５）

で表されるアニオン
［式中、Ａｒは、それぞれ独立して、置換基を有してもよいアリール基又は置換基を有してもよいヘテロアリール基であり、Ｒは、炭素数１～１０のアルキル基、炭素数３～２０のシクロアルキル基、炭素数１～１０のフルオロアルキル基、炭素数７～１０のアラルキル基又は炭素数７～１０のフルオロアラルキル基であり、Ｌは、アルキレン基、－ＮＨ－、酸素原子、硫黄原子又は－ＣＮ⁺－であり、Ｅは長周期型周期表の第１３族又は第１５族に属する元素を表す］からなる群より選択される少なくとも１種のアニオンと対カチオンとからなるオニウムボレート塩（ただし、電気的中性な塩である）；
（Ｃ）有機溶媒を含む液体担体；及び
（Ｆ）マトリックス化合物
を含む組成物を提供する。本構成のインク組成物を使用すると、薄膜作製時のバイルアップがいっそう改善され、厚さが均一で電荷輸送性に優れた電荷輸送性薄膜とすることができる。 The present application further provides an ink composition comprising:
(A) Formula (I):

[wherein R ₁ and R ₂ are each independently H, alkyl, fluoroalkyl, alkoxy, fluoroalkoxy, aryloxy, -SO ₃ M, or -O-[ZO] _p -R _e Alternatively, R ₁ and R ₂ together form —O—ZO—, where M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium and Z is a hydrocarbylene group optionally substituted with halogen or Y (where Y is a linear or branched alkyl or alkoxyalkyl group having 1 to 10 carbon atoms, and the alkyl or an alkoxyalkyl group may be substituted with a sulfonic acid group at any position), p is an integer greater than or equal to 1, and R _e is H, alkyl, fluoroalkyl, or aryl is)] polythiophene containing a repeating unit represented by;
(B) an onium borate salt of formula (a1):

An anion of the formula (a2):

A monovalent or divalent anion represented by and (a5)

[Wherein Ar is each independently an optionally substituted aryl group or optionally substituted heteroaryl group, R has 1 to 10 carbon atoms an alkyl group, a cycloalkyl group having 3 to 20 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms or a fluoroaralkyl group having 7 to 10 carbon atoms, and L is an alkylene group , -NH-, an oxygen atom, a sulfur atom or -CN ⁺ -, and E represents an element belonging to Group 13 or Group 15 of the long period periodic table]. An onium borate salt consisting of an anion and a countercation (provided that it is an electrically neutral salt);
(C) a liquid carrier comprising an organic solvent; and (F) a matrix compound. By using the ink composition of this configuration, build-up during thin film formation is further improved, and a charge-transporting thin film having a uniform thickness and excellent charge-transporting properties can be obtained.

[Ink composition]

The ink composition can be prepared by any suitable method known to those skilled in the art. For example, in one method, the initial aqueous mixture is a dispersion of polythiophenes described herein, optionally mixed with an aqueous dispersion of a matrix compound such as a polymeric acid, and optionally an additional solvent. It is prepared by Solvents, including water, in the mixture are then removed, typically by evaporation. The resulting dry product is dissolved or dispersed in one or more organic solvents such as dimethylsulfoxide, glycol-based solvents and filtered under pressure to produce a non-aqueous mixture. By mixing such a non-aqueous mixture with an onium borate salt or a solution or dispersion thereof, optionally an amine compound, a dispersion of metal oxide nanoparticles and a matrix compound or a dispersion or solution thereof, the final ink composition can manufacture things. The order of addition of these components is not particularly limited, and the ink composition can be produced in any order of addition.

In another method, the ink compositions described herein can be prepared from stock solutions. For example, the polythiophene stock solutions described herein can be prepared by isolating the polythiophene in the dry state, typically by evaporation, from an aqueous dispersion. The dried polythiophene is then combined with one or more organic solvents and optionally an amine compound. A stock solution of the onium borate salt can be prepared by dissolving in an organic solvent. A stock solution of the matrix compound, when the matrix compound is a polymeric acid, can be prepared by isolating the polymeric acid in a dry state, typically by evaporation, from an aqueous dispersion. The dried polymeric acid is then combined with one or more organic solvents. Stock solutions of other matrix compounds can be similarly prepared. A stock solution of metal oxide nanoparticles, for example, is a commercially available dispersion in one or more organic solvents, which may be the same or different from the solvent(s) contained in the commercially available dispersion. It can be prepared by diluting with a good organic solvent. Desired amounts of each stock solution are then combined to form the ink compositions of the present disclosure.

In yet another method, the ink compositions described herein isolate the individual components in the dry state as described herein, but instead of preparing a stock solution, the dry components are combined. and then dissolving in one or more organic solvents to provide an NQ ink composition.

The amine compound is usually added when the ink composition is finally prepared, but it may be added in advance at an earlier time. For example, when sulfonated polythiophene is used as the component (A), as described above, an amine compound is added to the sulfonated polythiophene to obtain a corresponding ammonium salt such as a trialkylammonium salt (sulfonated polythiophene amine adduct). can be converted to If desired, the ammonium salt can be subjected to a reduction treatment, or an amine compound (e.g., triethylamine) is added to a solution of the reduced sulfonated polythiophene to convert the sulfonated polythiophene to an ammonium salt (e.g., triethylammonium). As a salt), it may be precipitated in the form of a powder and recovered.
The method of such treatment is not particularly limited, but for example, water and triethylamine are added to the reduction-treated sulfonated polythiophene to dissolve it, and after stirring while heating (for example, 60° C.), the resulting solution is isopropyl alcohol and acetone to precipitate the triethylammonium salt of the sulfonated conjugated polymer, which is recovered by filtration.

The total solids content (% TS) in the ink composition is from about 0.1 wt% to about 50 wt%, typically from about 0.3 wt% to about 40 wt%, based on the total weight of the ink composition. , more typically from about 0.5% to about 15% by weight, and even more typically from about 1% to about 5% by weight.

[Method for Forming Charge-Transporting Thin Film]
A charge-transporting thin film can be produced by coating the ink composition on a substrate and evaporating the solvent. The charge-transporting thin film is preferably a hole-transporting thin film.
The ink composition of the present disclosure can be cast and annealed as a thin film on a substrate.

Accordingly, the present disclosure also provides a method of forming a hole transporting thin film comprising:
1) coating a substrate with an ink composition disclosed herein; and 2) forming a hole transporting thin film by annealing the coating on the substrate.

Coating of the ink composition on a substrate can be performed, for example, by spin casting, spin coating, dip casting, dip coating, slot die coating, inkjet printing, gravure coating, doctor blading, and for the fabrication of organic electronic devices, for example. can be performed by any method known in the art, including any other method known in the art.

The substrate can be flexible or rigid, organic or inorganic. Suitable substrate compounds include, for example, glass (including, for example, display glass), ceramic, metal, and plastic films.

As used herein, the term "annealing" refers to any general process for forming a cured layer, typically a thin film, on a substrate coated with the ink composition of the present disclosure. Say. General annealing processes are known to those skilled in the art. Typically, the solvent is removed from the substrate coated with the ink composition. Removal of the solvent can be accomplished, for example, by subjecting the coated substrate to sub-atmospheric pressure and/or heating the coating laminated to the substrate to a temperature (annealing temperature) and maintaining this temperature for a period of time (annealing time ) and then allow the resulting layer, typically a thin film, to cool slowly to room temperature.

The step of annealing can be performed by heating the substrate coated with the ink composition using any method known to those skilled in the art, such as in an oven or on a hot plate. . Annealing can be performed in an inert environment, such as a nitrogen atmosphere or a noble gas (eg, argon gas, etc.) atmosphere. Annealing may be performed in an air atmosphere.

In some embodiments, the annealing temperature is from about 25°C to about 350°C, typically from 150°C to about 325°C, more typically from about 200°C to about 300°C, even more typically from about 230°C to about 325°C. It is about 300°C.

Annealing time is the time for which the annealing temperature is maintained. Annealing time is from about 3 to about 40 minutes, typically from about 15 to about 30 minutes.

In some embodiments, the annealing temperature is from about 25° C. to about 350° C., typically from 150° C. to about 325° C., more typically from about 200° C. to about 300° C., even more typically from about 250° C. to about 350° C. about 300° C., and the annealing time is about 3 to about 40 minutes, typically about 15 to about 30 minutes.

The present disclosure relates to hole-transporting thin films formed by the methods described herein.

Visible light transmission is important, and good transmission (low extinction) at high film thickness is especially important. For example, thin films produced by the methods of the present disclosure have a transmittance (typically with the substrate) of at least about 85%, typically at least 90%, for light having a wavelength of about 380-800 nm. can be shown. In some embodiments, the transmittance is at least about 90%.

In one embodiment, thin films produced by the methods of the present disclosure have a thickness of about 5 nm to about 500 nm, typically about 5 nm to about 150 nm, more typically about 50 nm to 120 nm.

In some embodiments, thin films produced by the methods of the present disclosure exhibit a transmittance of at least about 90% and exhibit a transmittance of about 5 nm to about 500 nm, typically about 5 nm to about 150 nm, more typically about 50 nm. It has a thickness of ~120 nm. In some embodiments, thin films produced by the methods of the present disclosure exhibit a transmittance (%T) of at least about 90% and have a thickness of about 50 nm to 120 nm.

Thin films produced by the methods of the present disclosure can be produced on substrates that optionally contain electrodes or additional layers used to enhance the electronic properties of the final device. The resulting thin films may be resistant to one or more organic solvents, which are used as liquid carriers in inks for layers that are subsequently coated or deposited during device fabrication. can be a solvent for Thin films are, for example, resistant to toluene, which can be a solvent in inks for layers that are subsequently coated or deposited during device fabrication.

[Organic EL device]
The present disclosure also relates to organic electroluminescent elements (devices) comprising thin films prepared by the methods described herein. Devices described herein can be manufactured by methods known in the art, including, for example, dissolution methods. The ink can be applied and the solvent removed by standard methods. Thin films prepared by the methods described herein may be HIL and/or HTL layers in devices.

Methods are known in the art and can be utilized to make organic electronic devices, including, for example, OLED and OPV devices. Methods known in the art are available for measuring luminance, efficiency, and lifetime. Organic light emitting diodes (OLEDs) are described, for example, in US Pat. Nos. 4,356,429 and 4,539,507 (Kodak). Conductive polymers that emit light are described, for example, in US Pat. Nos. 5,247,190 and 5,401,827 (Cambridge Display Technologies). Device architecture, physical principles, dissolution methods, multilayering, mixing, and compound synthesis and formulation are described in Kraft et al., "Electroluminescent Conjugated Polymers-Seeing Polymers in a New Light," Angew. Chem. Int. Ed., 1998, 37, 402-428, which is incorporated herein by reference in its entirety.

Various conductive compounds such as compounds available from Sumation, Merck Yellow, Merck Blue, from American Dye Sources (ADS), from Kodak (eg A1Q3, etc.), and indeed compounds available from Aldrich (BEHP-PPV, etc.) Emitters known in the art and commercially available can be used, including polymers as well as organic molecules. Examples of such organic electroluminescent compounds include:
(i) poly(p-phenylene vinylene) and its derivatives substituted at various positions on the phenylene residue;
(ii) poly(p-phenylenevinylene) and its derivatives substituted at various positions on the vinylene residue;
(iii) poly(p-phenylene vinylene) and derivatives thereof substituted at various positions on the phenylene residue and also substituted at various positions on the vinylene residue;
(iv) poly(arylene vinylene)s, wherein the arylene may be a residue such as naphthalene, anthracene, furylene, thienylene, oxadiazole, etc.;
(v) derivatives of poly(arylenevinylene), wherein the arylene may be as in (iv) above, and further have substituents at various positions on the arylene;
(vi) derivatives of poly(arylenevinylene), wherein the arylene may be as in (iv) above, and further have substituents at various positions on the vinylene;
(vii) Derivatives of poly(arylene vinylene), wherein the arylene may be the same as in (iv) above, and further have substituents at various positions on the arylene and a derivative having a substituent;
(viii) copolymers of arylene vinylene oligomers and non-conjugated oligomers, such as compounds in (iv), (v), (vi), and (vii); and (ix) poly(p-phenylene) and phenylene residues. derivatives thereof substituted at various positions on the group, including ladder polymer derivatives such as poly(9,9-dialkylfluorene);
(x) poly(arylene), where the arylene may be a residue such as naphthalene, anthracene, furylene, thienylene, oxadiazole, etc.; and various positions on the arylene residue. derivatives thereof substituted with;
(xi) copolymers of oligoarylenes and non-conjugated oligomers such as compounds in (x);
(xii) polyquinolines and derivatives thereof;
(xiii) copolymers of polyquinolines and p-phenylenes substituted on the phenylenes by, for example, alkyl or alkoxy groups to provide solubility;
(xiv) poly(p-phenylene-2,6-benzobisthiazole), poly(p-phenylene-2,6-benzobisoxazole), poly(p-phenylene-2,6-benzimidazole), and derivatives thereof Rigid rod polymers, as well as derivatives thereof, such as;
(xv) Polyfluorene polymers and copolymers having polyfluorene units.

Preferred organic light-emitting polymers include SUMATION's Light Emitting Polymers (“LEPs”) or families, copolymers, derivatives, or mixtures thereof that emit green, red, blue, or white light; SUMATION's LEPs are available from Sumation KK. Other polymers include polyspirofluorene-like polymers available from Covion Organic Semiconductors GmbH, Frankfurt, Germany (now owned by Merck®).

Alternatively, organic small molecules that emit fluorescence or phosphorescence, rather than polymers, can be used as the organic electroluminescent layer. Examples of small molecule organic electroluminescent compounds are (i) tris(8-hydroxyquinolinato)aluminum (Alq); (ii) 1,3-bis(N,N-dimethylaminophenyl)-1,3,4 (iii) oxo-bis(2-methyl-8-quinolinato)aluminum; (iv) bis(2-methyl-8-hydroxyquinolinato)aluminum; (v) bis(hydroxy benzoquinolinato)beryllium (BeQ ₂ ); (vi) bis(diphenylvinyl)biphenylene (DPVBI); and arylamine-substituted distyrylarylenes (DSA amines).

Such polymers and small molecules are well known in the art and are described, for example, in US Pat. No. 5,047,687.

Devices can often be fabricated using multilayer structures that can be prepared by, for example, solution or vacuum methods, as well as printing and patterning methods. In particular, utilization of the embodiments described herein for a hole injection layer (HIL), wherein the composition is formulated for use as a hole injection layer, is effectively can run to

Examples of HIL in devices include:
1) Hole injection in OLEDs, including PLEDs and SMOLEDs; for example, HILs in PLEDs can use all classes of conjugated polymer emitters where the conjugation involves carbon or silicon atoms. For HIL in SMOLEDs, the following are examples: SMOLEDs containing fluorescent emitters; SMOLEDs containing phosphorescent emitters; SMOLEDs containing one or more organic layers in addition to the HIL layer; or SMOLEDs that have been treated from aerosol sprays or by any other treatment method. Still other examples include: HIL in OLEDs based on dendrimer or oligomeric organic semiconductors; HIL in ambipolar light-emitting FETs, where the HIL is used to regulate charge injection or as an electrode. ;
2) a hole extraction layer in the OPV;
3) channel materials in transistors;
4) channel materials in circuits containing combinations of transistors, such as logic gates;
5) electrode materials in transistors;
6) gate layers in capacitors;
7) chemical sensors in which doping level control is achieved by the relationship between the species to be sensed and the conducting polymer;
8) Electrode or electrolyte materials in batteries.

Various photoactive layers can be used in OPV devices. Photovoltaic devices include, for example, fullerene derivatives mixed with conducting polymers, such as those described in U.S. Pat. Nos. 5,454,880; 6,812,399; can be prepared with a photoactive layer comprising Photoactive layers can include mixtures of conducting polymers, mixtures of conducting polymers and semiconducting nanoparticles, and bilayers of small molecules such as phthalocyanines, fullerenes, and porphyrins.

Common electrode compounds and substrates as well as encapsulating compounds can be used.

In one embodiment, the cathode comprises Au, Ca, Al, Ag, or combinations thereof. In one embodiment, the anode comprises indium tin oxide. In one embodiment, the emissive layer comprises at least one organic compound.

For example, interfacial modification layers, such as intermediate layers, and optical spacer layers can be used.

An electron transport layer can be used.

The present disclosure also relates to methods of manufacturing the devices described herein.

In some embodiments, the method of making the device includes: providing a substrate; laminating a transparent conductor, such as indium tin oxide, on the substrate; providing; forming a hole injection layer or hole transport layer by laminating an ink composition on a transparent conductor; laminating an active layer on the hole injection layer or hole transport layer (HTL) and laminating the cathode onto the active layer.

As described herein, the substrate can be flexible or rigid, organic or inorganic. Suitable substrate compounds include, for example, glass, ceramic, metal, and plastic thin films.

In another embodiment, the method of making a device comprises applying the ink composition described herein to an OLED, photovoltaic device, ESD, SMOLED, PLED, sensor, supercapacitor, cation converter, drug release device, electro Including application as part of a HIL or HTL layer in chromic devices, transistors, field effect transistors, electrode modifiers, electrode modifiers for organic field effect transistors, actuators or transparent electrodes.

Lamination of the ink composition to form the HIL or HTL layer can be performed by methods known in the art (e.g. spin casting, spin coating, dip casting, dip coating, slot die coating, inkjet printing, gravure coating, doctor blading, and any other method known in the art for making organic electronic devices, for example).

In one embodiment, the HIL layer is thermally annealed. In one embodiment, the HIL layer is thermally annealed at a temperature of about 25°C to about 350°C, typically 150°C to about 325°C. In one embodiment, the HIL layer is heat treated at a temperature of about 25° C. to about 350° C., typically 150° C. to about 325° C., for about 3 to about 40 minutes, typically about 15 to about 30 minutes. effectively annealed.

According to the present disclosure, a HIL or HTL that can exhibit a transmittance (typically with a substrate) of at least about 85%, typically at least about 90%, for light having a wavelength of about 380-800 nm. can be prepared. In some embodiments, the transmittance is at least about 90%.

In one embodiment, the HIL layer has a thickness of about 5 nm to about 500 nm, typically about 5 nm to about 150 nm, more typically about 50 nm to 120 nm.

In some embodiments, the HIL layer exhibits a transmittance of at least about 90% and has a thickness of about 5 nm to about 500 nm, typically about 5 nm to about 150 nm, more typically about 50 nm to 120 nm. . In some embodiments, the HIL layer exhibits a transmittance (%T) of at least about 90% and has a thickness of about 50 nm to 120 nm.

The disclosed inks, methods and processes, thin films, and devices are further illustrated by the following non-limiting examples.

[1] Synthesis of onium borate salt [Synthesis Example 1] Synthesis of onium borate salt (P-1) P-1 represented by the following formula was synthesized by the following method.

A 10 L four-necked flask was charged with 6,068 mL of diethyl ether, 151.7 g of the compound represented by the following formula (Q-1), and 9.4 g of KCN, and reacted at 34 to 36° C. for 3 hours. After the reaction, concentration under normal pressure was performed to obtain 267.2 g of brown liquid. The obtained brown liquid was concentrated by an evaporator at 55° C. and dried under reduced pressure at 35° C. for 16 hours to obtain 157.7 g of an intermediate represented by the formula (Q-2) as a pale brown solid. . The obtained intermediate (Q-2) was identified by LDI-MS.
LDI-MS m/Z found: 1050.12 ([M ^] -calcd:
1049.97).

A 300 mL conical flask was charged with 11.043 g of diphenyl[4-(phenylthio)phenyl]sulfonium trifluoromethanesulfonate, 22.000 g of intermediate (Q-2), 110 mL of ion-exchanged water, and 110 mL of diethyl ether, and the mixture was heated at 25° C. for 16 hours. reacted. After the reaction, the contents of the flask were transferred to a 300 mL separating funnel to separate the aqueous layer. The ether layer was washed 5 times with 100 mL of ion-exchanged water. The ether layer was concentrated by an evaporator at 40 to 45° C. and dried under reduced pressure for 20 hours to obtain 24.000 g of the desired product as a pale yellow solid. The target product obtained was identified by ¹ H-NMR and LDI-MS.
¹ H-NMR (300MHz, DMSO-d6): δ7.40-7.80 (19H, m)
LDI-MS m/Z found: 371.04 ([M] ⁺ calcd:
371.09).
LDI-MS m/Z found: 1050.11 ([M ^] -calcd:
1049.97).

[Synthesis Example 2] Synthesis of onium borate salt (P-2) P-2 represented by the following formula was synthesized by the following method.

38.1 g of tris(pentafluorophenyl)borane (manufactured by Tokyo Chemical Industry Co., Ltd.) and 1200 g of pentane were charged into a reaction vessel, and 38.8 g of a hexane solution of n-butyllithium (1.6 M) was added at room temperature while stirring. It was added dropwise and reacted at room temperature for 3 hours to obtain a slurry-like reaction liquid.
The crystals obtained by filtering the reaction solution were spray-washed with pentane and dried under reduced pressure at 60° C. to obtain 38.1 g of the intermediate lithium n-butyltris(pentafluorophenyl)borate (yield 89). %).

Subsequently, 22.5 g of (4-phenylthiophenyl) diphenylsulfonium hexafluorophosphate (manufactured by San-Apro Co., Ltd.) was dissolved in 530 g of dichloromethane, and 30 g of the borate obtained above was dissolved in 400 g of deionized water. The resulting aqueous solution was added and mixed under stirring for 1 hour. After mixing, the mixture was allowed to stand, the aqueous layer was removed, and the dichloromethane solution was washed with 400 g of ion-exchanged water five times. The dichloromethane solution after washing with water was desolvated under reduced pressure to obtain 40 g of the desired product as a pale yellow solid of (4-phenylthiophenyl)diphenylsulfonium n-butyltris(pentafluorophenyl)borate salt (yield 97%). . The target product obtained was identified by ¹ H-NMR and ¹⁹ F-NMR.
¹ H-NMR (DMSO-d6): δ 7.6-7.8 (12H, m), 7.4-7.5 (5H, m), 7.3 (2H, d), 1.0- 1.2 (4H, m), 0.6-0.8 (5H, m) ppm.
¹⁹ F-NMR (DMSO-d6): δ −132 (6F, d), −159.5 (3F, t), −163 (6F, t) ppm.

[2] Preparation of charge-transporting substance [Synthesis Example 3] Preparation of sulfonated poly(3-MEET) (hereinafter also referred to as S-poly(3-MEET)) amine adduct S-poly(3-MEET) An aqueous dispersion (0.598% solids in water) was prepared by mixing 500 g with 0.858 g of triethylamine (manufactured by Tokyo Kasei Kogyo Co., Ltd.). The resulting mixture was rotary evaporated to dryness and then further dried in a vacuum oven at 50° C. overnight. The product was isolated as 3.8 g of black powder.
2.00 g of S-poly(3-MEET), which is a charge-transporting substance, was dissolved in 100 mL of 28% aqueous ammonia (manufactured by Junsei Chemical Co., Ltd.) and stirred overnight at room temperature. The reaction solution was reprecipitated with 1500 mL of acetone, and the precipitate was collected by filtration. The resulting precipitate was again dissolved in 20 mL of water and 7.59 g of triethylamine (manufactured by Tokyo Kasei Kogyo Co., Ltd.) and stirred at 60° C. for 1 hour. After cooling the reaction solution, it was reprecipitated with a mixed solvent of 1000 mL of isopropyl alcohol and 500 mL of acetone, and the precipitate was collected by filtration. The resulting precipitate was vacuum-dried at 0 mmHg and 50° C. for 1 hour to obtain 1.30 g of S-poly(3-MEET)-A treated with aqueous ammonia.

[3] Preparation of ink composition [Example 1-1]
2.28 g of ethylene glycol (manufactured by Kanto Chemical Co., Ltd.), diethylene glycol (manufactured by Kanto Chemical Co., Ltd.), ) and 0.20 g of n-butylamine (manufactured by Tokyo Kasei Kogyo Co., Ltd.). A hot stirrer was used to prepare the solution, and the mixture was stirred at 80° C. for 1 hour. Then, 1.25 g of triethylene glycol dimethyl ether (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added and stirred at 400 rpm and 80° C. for 1 hour using a hot stirrer. Finally, 0.125 g of P-1 was added and stirred with a hot stirrer at 400 rpm and 40° C. for 10 minutes. got stuff

[Example 1-2]
0.025 g of S-poly(3-MEET)-A, which is the charge-transporting substance obtained in Synthesis Example 3, was mixed with 2.35 g of ethylene glycol (manufactured by Kanto Chemical Co., Ltd.) ) and 0.04 g of n-butylamine (manufactured by Tokyo Kasei Kogyo Co., Ltd.). A hot stirrer was used to prepare the solution, and the mixture was stirred at 80° C. for 1 hour. Then, 1.25 g of triethylene glycol dimethyl ether (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added and stirred at 400 rpm and 80° C. for 1 hour using a hot stirrer. After standing to cool, 0.013 g of P-1, powdery 4-hydroxystyrene / styrene = 70/30 copolymer (Marukalinker CST7030 (manufactured by Maruzen Petrochemical Co., Ltd.)) as component (F) was added to 0. .213 g was added and stirred for 30 minutes at 400 rpm and 40° C. using a hot stirrer. The obtained solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a 4 wt % ink composition.

[Example 1-3]
0.025 g of S-poly(3-MEET)-A, which is the charge-transporting substance obtained in Synthesis Example 3, was mixed with 1.53 g of ethylene glycol (manufactured by Kanto Chemical Co., Ltd.), diethylene glycol (manufactured by Kanto Chemical Co., Ltd. ) and 0.04 g of n-butylamine (manufactured by Tokyo Kasei Kogyo Co., Ltd.). A hot stirrer was used to prepare the solution, and the mixture was stirred at 80° C. for 1 hour. Then, 1.25 g of triethylene glycol dimethyl ether (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added and stirred at 400 rpm and 80° C. for 1 hour using a hot stirrer. After cooling, 0.013 g of P-1, organosilica sol (EG-ST (manufactured by Nissan Chemical Industries, Ltd.), average particle size: 12 nm, solid content concentration: 20 to 21 wt%, dispersion medium: ethylene glycol). 1.04 g was added and stirred for 30 minutes at 400 rpm and 40° C. using a hot stirrer. The obtained solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a 4 wt % ink composition.

[Example 1-4]
0.025 g of S-poly(3-MEET)-A, which is the charge-transporting substance obtained in Synthesis Example 3, was mixed with 2.35 g of ethylene glycol (manufactured by Kanto Chemical Co., Ltd.) ) and 0.04 g of n-butylamine (manufactured by Tokyo Kasei Kogyo Co., Ltd.). A hot stirrer was used to prepare the solution, and the mixture was stirred at 80° C. for 1 hour. Then, 1.25 g of triethylene glycol dimethyl ether (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added and stirred at 400 rpm and 80° C. for 1 hour using a hot stirrer. After cooling, 0.013 g of P-2, powdery 4-hydroxystyrene / styrene = 70/30 copolymer (Marukalinker CST7030 (manufactured by Maruzen Petrochemical Co., Ltd.)) as component (F) was added to 0. .213 g was added and stirred for 30 minutes at 400 rpm and 40° C. using a hot stirrer. The obtained solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a 4 wt % ink composition.

[Example 1-5]
0.025 g of S-poly(3-MEET)-A, which is the charge-transporting substance obtained in Synthesis Example 3, was mixed with 4.70 g of ethylene glycol (manufactured by Kanto Chemical Co., Ltd.) ) and 0.04 g of n-butylamine (manufactured by Tokyo Kasei Kogyo Co., Ltd.). A hot stirrer was used to prepare the solution, and the mixture was stirred at 80° C. for 1 hour. Then, 2.50 g of triethylene glycol dimethyl ether (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added and stirred at 400 rpm and 80° C. for 1 hour using a hot stirrer. After standing to cool, 0.013 g of P-1, powdery 4-hydroxystyrene / styrene = 70/30 copolymer (Marukalinker CST7030 (manufactured by Maruzen Petrochemical Co., Ltd.)) as component (F) was added to 0. .213 g was added and stirred for 30 minutes at 400 rpm and 40° C. using a hot stirrer. The resulting solution was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a 2 wt % ink composition.

[Comparative Example 1]
First, the solvent of AQUIVION D66-20BS aqueous solution (manufactured by Solvay, tetrafluoroethylene/perfluoro-2-(vinyloxy)ethane-1-sulfonic acid copolymer, 676 g polymer/equivalent to 1 mol of acid) was distilled off by an evaporator. The obtained residue was dried under reduced pressure at 80° C. for 1 hour in a vacuum dryer to obtain a powder of D66-20BS. Using the obtained powder, a 10 wt % ethylene glycol solution of D66-20BS was prepared. The solution was prepared by stirring at 400 rpm and 90° C. for 1 hour using a hot stirrer.
Next, another container was prepared, and 0.020 g of S-poly(3-MEET)-A obtained in Synthesis Example 3 was added to 1.20 g of ethylene glycol (manufactured by Kanto Chemical Co., Ltd.), diethylene glycol (Kanto Chemical Co., Ltd.) 1.95 g, triethylene glycol dimethyl ether (manufactured by Tokyo Chemical Industry Co., Ltd.) 4.88 g, 2-(benzyloxy) ethanol (manufactured by Kanto Chemical Co., Ltd.) 0.98 g and n-butylamine (Tokyo 0.032 g (manufactured by Kasei Kogyo Co., Ltd.). The solution was prepared by stirring at 80° C. for 1 hour using a hot stirrer. Then, 0.10 g of a 10 wt % ethylene glycol solution of D66-20BS was added to the resulting solution, and the resulting mixture was stirred at 400 rpm and 80° C. for 1 hour using a hot stirrer. Finally, 0.83 g of organosilica sol (EG-ST (manufactured by Nissan Chemical Industries, Ltd.), average particle size: 12 nm, solid content concentration: 20 to 21 wt%, dispersion medium: ethylene glycol) was added, and the resulting mixture was stirred with a hot stirrer at 400 rpm and 80° C. for 10 minutes, and the resulting dispersion was filtered through a PP syringe filter with a pore size of 0.2 μm to obtain a 2 wt % ink composition.

[4] Fabrication and property evaluation of organic EL device [Examples 2-1 to 2-4]
Using the ink compositions obtained in Examples 1-1 to 1-4, organic EL devices of Examples 2-1 to 2-4 were produced according to the following procedure.
Each of the compositions obtained in Examples 1-1 to 1-4 was applied to an ITO substrate using a spin coater and then dried for 15 minutes using a vacuum dryer. Next, each dried ITO substrate was inserted into a glove box and baked at 230° C. for 30 minutes under nitrogen to form a hole injection layer with a thickness of 50 nm on the ITO substrate. As the ITO substrate, a 25 mm × 25 mm × 0.7 _t glass substrate on which indium tin oxide (ITO) was patterned with a film thickness of 150 nm was used. Surface impurities were removed.

Next, α- ^NPD (N,N'-di(1- Naphthyl)-N,N'-diphenylbenzidine) was deposited to a thickness of 30 nm at 0.2 nm/sec. Next, an electron blocking material HTEB-01 manufactured by Kanto Kagaku Co., Ltd. was deposited to a thickness of 10 nm as a hole transport layer. Next, a light-emitting layer host material NS60 manufactured by Nippon Steel & Sumikin Chemical Co., Ltd. and a light-emitting layer dopant material Ir(PPy) ₃ were co-deposited as a light-emitting layer. In the co-evaporation, the deposition rate was controlled so that the concentration of Ir(PPy) ₃ was 6%, and the thickness was 40 nm. Subsequently, thin films of Alq ₃ as an electron transport layer, lithium fluoride as an electron injection layer, and aluminum as a cathode layer were successively laminated to obtain an organic EL device. At this time, the deposition rate was 0.2 nm/sec for Alq ₃ and aluminum, and 0.02 nm/sec for lithium fluoride, respectively, and the film thicknesses were 20 nm, 0.5 nm and 80 nm, respectively.
In order to prevent deterioration of characteristics due to the influence of oxygen, water, etc. in the air, the characteristics of the organic EL element were evaluated after being sealed with a sealing substrate. Sealing was performed by the following procedure. In a nitrogen atmosphere with an oxygen concentration of 2 ppm or less and a dew point of −76° C. or less, the organic EL element was placed between the sealing substrates, and the sealing substrates were glued (manufactured by MORESCO Co., Ltd., MORESCO Moisture Cut WB90US (P)). pasted together by At this time, a water trapping agent (HD-071010W-40 manufactured by Dainic Co., Ltd.) was contained in the sealing substrate together with the organic EL element. The bonded sealing substrates were irradiated with UV light (wavelength: 365 nm, irradiation amount: 6,000 mJ/cm ² ) and then annealed at 80° C. for 1 hour to cure the adhesive.

For the devices of Examples 2-1 to 2-4, the drive voltage, current density and luminous efficiency (current efficiency and external quantum efficiency) when driven at a luminance of 10000 cd/m ² , and luminance half-life (initial luminance 10000 cd/m The time required for m ² to reach half) was measured. Table 1 shows the results.

The luminance, driving voltage, current density, current efficiency and external quantum efficiency were measured using a multi-channel IVL measuring device manufactured by EHC Co., Ltd. The luminance half-life was measured by an organic EL luminance life evaluation system PEL-105S manufactured by EHC Co., Ltd.

As shown in Examples 2-1 to 2-4, (A) a polythiophene containing a repeating unit represented by formula (I), and (B) an anion and a counter cation represented by formula (a1) or (a2) An ink composition containing an onium borate salt consisting of and a liquid carrier containing an organic solvent was applicable to a wet process, and a hole injection layer formed from the composition was well driven as an organic EL device.

A comparison of Examples 2-1 and 2-2 reveals that the current efficiency, external quantum efficiency and luminance half-life of the produced organic EL device are improved when the ink composition further contains (F) the matrix compound, which is preferable. From a comparison of Examples 2-1 and 2-3, when the ink composition further contained (E) metal oxide nanoparticles, the current efficiency, external quantum efficiency and luminance half-life of the produced organic EL device were improved. ,preferable.

[5] Preparation of positive photosensitive resin composition The abbreviations used in the following synthesis examples have the following meanings.
MMA: methyl methacrylate HEMA: 2-hydroxyethyl methacrylate HPMA: 4-hydroxyphenyl methacrylate HPMA-QD: condensation reaction of 1 mol of 4-hydroxyphenyl methacrylate and 1.1 mol of 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride CHMI: N-cyclohexylmaleimide PFHMA: 2-(perfluorohexyl)ethyl methacrylate MAA: methacrylic acid AIBN: α,α'-azobisisobutyronitrile QD1: α,α,α'-tris( 4-Hydroxyphenyl)-1-ethyl-4-isopropylbenzene (1 mol) and 1,2-naphthoquinone-2-diazide-5-sulfonyl chloride (1.5 mol) are synthesized by condensation reaction GT-401: Butanetetracarboxylic acid. Tetra(3,4-epoxycyclohexylmethyl)-modified ε-caprolactone (trade name: Epolead GT-401 (manufactured by Daicel Corporation))
PGME: propylene glycol monomethyl ether PGMEA: propylene glycol monomethyl ether acetate CHN: cyclohexanone

[Measurement of number average molecular weight and weight average molecular weight]
The number average molecular weight and weight average molecular weight of the copolymer obtained according to the following synthesis examples were measured using a GPC apparatus manufactured by Tosoh Corporation (Shodex column KD800 and TOSOH column TSK-GEL), and the elution solvent N,N'-dimethyl Formamide (10 mmol/L (liter) mixture of lithium bromide-hydrate (LiBr.H ₂ O) as an additive) is passed through the column (column temperature 40° C.) at a flow rate of 1 ml/min for elution. measured in The number average molecular weight (hereinafter referred to as Mn) and weight average molecular weight (hereinafter referred to as Mw) below are expressed in terms of polystyrene.

<Synthesis Example 4>
10.0 g of MMA, 12.5 g of HEMA, 20.0 g of CHMI, 2.50 g of HPMA, 5.00 g of MAA and 3.20 g of AIBN are dissolved in 79.8 g of PGME and reacted at 60° C. to 100° C. for 20 hours. to obtain an acrylic polymer solution (solid concentration: 40 wt %) (P3). The obtained acrylic polymer P3 had an Mn of 3,700 and an Mw of 6,100.

<Synthesis Example 5>
2.50 g of HPMA-QD, 7.84 g of PFHMA, 0.70 g of MAA, 1.46 g of CHMI and 0.33 g of AIBN were dissolved in 51.3 g of CHN and stirred at 110° C. for 20 hours to react to give an acrylic A polymer solution (solid concentration: 20 wt %) was obtained (P4). The obtained acrylic polymer P4 had an Mn of 4,300 and an Mw of 6,300.

5.04 g of P3 obtained in Synthesis Example 4, 0.05 g of P4 obtained in Synthesis Example 5, 0.40 g of QD1, 0.09 g of GT-401 and 6.42 g of PGMEA were mixed and stirred at room temperature for 3 hours. A positive photosensitive resin composition was prepared by making a uniform solution.

[6] Preparation of banked substrate using UV-312 manufactured by Technovision Co., Ltd. On an ITO-glass substrate that has been ozone-cleaned for 10 minutes, a spin coater is used to apply the positive type obtained in the above step [5]. After applying the photosensitive resin composition, the substrate was pre-baked on a hot plate (heated at 100° C. for 120 seconds) to form a thin film having a thickness of 1.2 μm. This thin film is irradiated with ultraviolet rays (light intensity at 365 nm: 5.5 mW/cm ² ) was irradiated for a certain period of time. Thereafter, the thin film was developed by immersing it in a 2.38% TMAH (tetramethylammonium hydroxide) aqueous solution for 20 seconds, and then washed with running ultrapure water for 20 seconds. Next, the thin film having the rectangular pattern formed thereon was post-baked (heated at 230° C. for 30 minutes) to cure it, thereby producing a substrate with banks.

[7] Evaluation of cross-sectional shape of charge-transporting thin film [Example 3] and [Comparative example 2]
Inkjet Designer manufactured by Cluster Technology Co., Ltd. was used in the rectangular openings (film formation regions) on the banked substrate obtained in the above step [6], and the ink obtained in Examples 1-5 and Comparative Example 1 was used. Each of the ink compositions was discharged, and the resulting coating film was dried under reduced pressure (degree of vacuum) of 10 Pa or less for 15 minutes, and then dried on a hot plate at 230 ° C. for 30 minutes. A charge-transporting thin film of Comparative Example 2 was formed.
The cross-sectional shapes of the charge-transporting thin films of Example 3 and Comparative Example 2 were measured with a fine shape measuring machine ET4000A (manufactured by Kosaka Laboratory Ltd.). The results obtained are shown in FIG.

Comparing Example 3 and Comparative Example 2, the cross-sectional shape of the charge-transporting thin film of Example 3 is different from that of the thin film of Comparative Example 2 in that the film creeps up in the vicinity of the bank (thickness of the film increases). increase) is clearly small.
From the above results, (A) a polythiophene containing a repeating unit represented by the formula (I), and (B) an onium borate composed of an anion and a counter cation represented by the formula (a1), (a2) or (a5) It was confirmed that by using an ink composition containing a salt, (C) a liquid carrier containing an organic solvent, and (F) a matrix compound, it is possible to suppress pile-up during formation of a charge-transporting thin film. As a result, in the organic EL device obtained using the ink composition of the present invention, there is no decrease in openings due to pile-up, and there is no unevenness in light emission due to uneven thickness of the light-emitting layer, and the device characteristics are greatly improved. It is hoped that this will improve.

The ink composition of the present invention can be used as a charge-transporting thin film material for organic electroluminescence devices.

Claims (27)

An ink composition comprising:
(A) Formula (I):

[wherein R ₁ and R ₂ are each independently H, alkyl, fluoroalkyl, alkoxy, fluoroalkoxy, aryloxy, -SO ₃ M, or -O-[ZO] _p -R _e Alternatively, R ₁ and R ₂ together form —O—ZO—, where
M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium;
Z is a hydrocarbylene group optionally substituted with halogen or Y (where Y is a linear or branched alkyl group or alkoxyalkyl group having 1 to 10 carbon atoms, and the alkyl group or alkoxy the alkyl group may be substituted with a sulfonic acid group at any position),
p is an integer greater than or equal to 1, and R _e is H, alkyl, fluoroalkyl, or aryl)]
Polythiophene containing a repeating unit represented by;
(B) an onium borate salt of formula (a1):

and an anion of formula (a2):

A monovalent or divalent anion represented by [wherein,
Ar is each independently an optionally substituted aryl group or an optionally substituted heteroaryl group,
R is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms or a fluoroaralkyl group having 7 to 10 carbon atoms. and
L is an alkylene group, -NH-, an oxygen atom, a sulfur atom or -CN ⁺ -]
An onium borate salt (provided that the salt is electrically neutral) consisting of at least one anion and a counter cation selected from the group consisting of; and (C) a composition comprising a liquid carrier containing an organic solvent. 2. The ink composition according to claim 1, wherein Ar is an aryl group having one or more electron-withdrawing substituents. 3. The ink composition according to claim 2, wherein the electron-withdrawing substituent is a halogen atom. The ink composition according to any one of claims 1 to 3, wherein the anion is represented by formula (a3).

The counter cation is represented by formulas (c1) to (c5):

5. The ink composition according to any one of claims 1 to 4, which is selected from the group consisting of 6. The ink composition according to any one of claims 1 to 5, wherein component (B) is represented by the following formula.

R ₁ and R ₂ are each independently H, fluoroalkyl, -SO ₃ M, -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e , or -OR _f , or R ₁ and R ₂ taken together form —O—(CH ₂ ) _q —O—, where (CH ₂ ) _q is optionally substituted with Y; wherein M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium, and each R _a , R _b , R _c , and R _d is each independently H, halogen, alkyl, fluoroalkyl, or aryl; R _e is H, alkyl, fluoroalkyl, or aryl; p is 1, 2, or 3; R _f is alkyl, fluoroalkyl or aryl; q is 1, 2, or 3; and Y is a linear or branched alkoxyalkyl group having 1 to 10 carbon atoms, the alkoxyalkyl group being sulfone at any position; 7. The ink composition according to any one of claims 1 to 6, which is optionally substituted with an acid group. The ink composition of any one of claims 1-7, wherein R ₁ is H and R ₂ is other than H. The ink composition according to any one of claims 1 to 7, wherein both R ₁ and R ₂ are other than H. R ₁ and R ₂ are each independently -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e or -OR _f , or R ₁ and 10. The ink composition of claim 9, wherein R ₂ together form -O-(CH ₂ ) _q -O-. 10. The ink composition of claim 9, wherein R ₁ and R ₂ are both -O[C(R _a R _b )-C(R _c R _d )-O] _p -R _e . each R _a , R _b , R _c , and R _d is each independently H, (C ₁ -C ₈ )alkyl, (C ₁ -C ₈ )fluoroalkyl, or phenyl _; , (C ₁ -C ₈ )alkyl, (C ₁ -C ₈ )fluoroalkyl, or phenyl. (A) component is represented by the following formula:

wherein M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium), and a repeating unit selected from the group consisting of combinations thereof; The ink composition according to any one of claims 1 to 12. The ink composition according to any one of claims 1 to 13, wherein component (A) is sulfonated poly(3-MEET). 15. The ink composition according to any one of claims 1 to 14, wherein component (A) contains the repeating unit represented by formula (I) in an amount of more than 50% by weight based on the total weight of the repeating units. . 16. The ink composition according to any one of claims 1 to 15, wherein component (C) comprises at least one selected from the group consisting of glycol monoethers, glycol diethers and glycols. 17. The ink composition according to any one of claims 1 to 16, further comprising (D) an amine compound. 18. The ink composition according to claim 17, wherein the component (D) comprises (D1) a tertiary alkylamine compound and (D2) an amine compound other than the tertiary alkylamine compound. 19. The ink composition according to claim 18, wherein the component (D2) is a primary alkylamine compound. Claim 19, wherein the primary alkylamine compound is at least one selected from the group consisting of ethylamine, n-butylamine, t-butylamine, 2-ethylhexylamine, n-hexylamine, n-decylamine and ethylenediamine. ink composition. 21. The ink composition according to claim 19 or 20, wherein the primary alkylamine compound is n-butylamine. The ink composition according to any one of claims 1 to 21, further comprising (E) metal oxide nanoparticles. 23. The ink composition according to any one of claims 1 to 22, further comprising (F) a matrix compound. A charge-transporting thin film formed from the ink composition according to any one of claims 1 to 23. 25. An organic electroluminescence device comprising the charge-transporting thin film according to claim 24. 24. A method for producing a charge-transporting thin film, which comprises applying the ink composition according to any one of claims 1 to 23 onto a substrate and evaporating the solvent. An ink composition comprising:
(A) Formula (I):

[wherein R ₁ and R ₂ are each independently H, alkyl, fluoroalkyl, alkoxy, fluoroalkoxy, aryloxy, -SO ₃ M, or -O-[ZO] _p -R _e Alternatively, R ₁ and R ₂ together form —O—ZO—, where
M is H, alkali metal, ammonium, monoalkylammonium, dialkylammonium, or trialkylammonium;
Z is a hydrocarbylene group optionally substituted with halogen or Y (where Y is a linear or branched alkyl group or alkoxyalkyl group having 1 to 10 carbon atoms, and the alkyl group or alkoxy the alkyl group may be substituted with a sulfonic acid group at any position),
p is an integer greater than or equal to 1, and R _e is H, alkyl, fluoroalkyl, or aryl)]
Polythiophene containing a repeating unit represented by;
(B) an onium borate salt of formula (a1):

An anion represented by the formula (a2):

A monovalent or divalent anion represented by and (a5)

An anion represented by [wherein
Ar is each independently an optionally substituted aryl group or an optionally substituted heteroaryl group,
R is an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, a fluoroalkyl group having 1 to 10 carbon atoms, an aralkyl group having 7 to 10 carbon atoms or a fluoroaralkyl group having 7 to 10 carbon atoms. and
L is an alkylene group, -NH-, an oxygen atom, a sulfur atom or -CN ⁺ -,
E represents an element belonging to Group 13 or Group 15 of the long period periodic table]
An onium borate salt (provided that it is an electrically neutral salt) consisting of at least one anion and a counter cation selected from the group consisting of;
(C) a liquid carrier comprising an organic solvent; and (F) a composition comprising a matrix compound.

Images