JP6115727B2 - Resin composition for display substrate - Google Patents

Description

  The present invention relates to a resin composition for a display substrate, and more particularly to a resin composition for a display substrate capable of forming a useful polyimide film having an appropriate linear expansion coefficient and an appropriate flexibility.

Polyimide resins are widely used in the field of electrical and electronic materials because of their high heat resistance, flame retardancy, and excellent electrical insulation. Specifically, it is used as a film for flexible printed wiring boards and heat-resistant adhesive tapes as a film, and as a resin varnish for semiconductor insulating films, protective films, and the like.
On the other hand, display devices such as an organic EL (Electroluminescence) display and a liquid crystal display have been demanded only for high definition, but their applications are rapidly expanding to information devices and the like. For example, a flexible display using a plastic film as a substrate is attracting attention in order to satisfy the demand for ultra-thin and light weight.
Conventionally, an active matrix driving panel is used for a high-definition display. In order to form an active matrix layer including a thin film active element in addition to a matrix-like pixel electrode, a high temperature treatment of 200 ° C. or higher is required in the manufacturing process, and extremely accurate alignment is required. However, since the heat resistance and the dimensional stability are inferior by changing from a glass substrate to a plastic material for flexibility, it is very difficult to form an active element directly on it.

Therefore, in order to avoid such a problem, a polyimide film is formed on a glass substrate, the manufacturing conditions are not limited, and an amorphous silicon TFT element, a color filter, etc. are formed with high-definition alignment to form a transfer layer. Thereafter, a method of manufacturing a display element by transferring and forming the transfer layer on a plastic film has been proposed (Patent Documents 1 and 2).
By the way, a linear expansion coefficient is mentioned as a characteristic of the polyimide required at the said process. However, in many polyimide systems, the linear expansion coefficient of the film is in the range of 60 to 80 ppm / K and does not have low linear expansion characteristics. Under such circumstances, a polyimide film having a low linear expansion coefficient has been developed. However, since an acid dianhydride having poor versatility is used as a raw material, the resulting product becomes expensive (Patent Document 3).

JP 2001-356370 A Special table 2010-539293 International Publication No. 2008/047591 Pamphlet

  The present invention has been made in view of such circumstances, and a useful cured film having an appropriate linear expansion coefficient and an appropriate flexibility without using an acid dianhydride having poor versatility as a raw material. It aims at providing the resin composition for display substrates which can be formed. In addition, moderate softness | flexibility here means self-supporting property and the high softness | flexibility of the grade which is not cracked even if it bends 90 degree | times.

  As a result of intensive studies to achieve the above object, the present inventors combined an acid anhydride having a biphenyl skeleton as an acid dianhydride component and a biphenyldiamine having a hydroxy group or a carboxyl group as a diamine component. By using it, a useful cured film having an appropriate linear expansion coefficient and an appropriate flexibility can be obtained from a resin composition for a display substrate containing a polyamic acid or polyimide derived from the acid dianhydride component and the diamine component. The present invention has been completed.

［式（１）乃至式（４）中、
Ｘ¹は芳香族基と２つ以上のカルボニル基を有する４価の有機基を表し、
Ｙ¹は２価の有機基を表し、
Ｙ²はアルカリ可溶性基を有する２価の有機基を表し、
ｎ及びｍは自然数を表す。］
第２観点として、前記Ｙ²が下記式（５）で表される構造である、第１観点に記載のディスプレイ基板用樹脂組成物に関する。

（式中、
Ｒ¹乃至Ｒ³は、それぞれ独立して、水素原子、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基、Ｗ¹で置換されていてもよいフェニル基、Ｗ¹で置換されていてもよいナフチル基、Ｗ¹で置換されていてもよいチエニル基又はＷ¹で置換されていてもよいフリル基を表し、
Ｗ¹は、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基又はカルボキシル基を表し、
Ｖ¹は、アルカリ可溶性基を表し、
ｋは、１乃至３の整数を表す。なお、○は結合手を表す。）
第３観点として、前記Ｖ¹がヒドロキシ基又はカルボキシル基を表す、第２観点に記載のディスプレイ基板用樹脂組成物に関する。
第４観点として、前記Ｖ¹がヒドロキシ基を表し、かつ、前記Ｒ¹乃至Ｒ³が、それぞれ独立して、水素原子、ハロゲン原子、炭素原子数１乃至３のアルキル基、又は炭素原子数１乃至３のアルコキシ基を表す、第３観点に記載のディスプレイ基板用樹脂組成物に関する。
第５観点として、前記Ｒ¹乃至Ｒ³が水素原子を表し、かつ前記ｋが２を表す、第４観点に記載のディスプレイ基板用樹脂組成物に関する。
第６観点として、前記Ｙ²が下記式（６）で表される構造である、第１観点に記載のディスプレイ基板用樹脂組成物に関する。

（式中、
Ｒ⁴乃至Ｒ⁹は、それぞれ独立して、水素原子、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基、Ｗ¹で置換されていてもよいフェニル基、Ｗ¹で置換されていてもよいナフチル基、Ｗ¹で置換されていてもよいチエニル基又はＷ¹で置換されていてもよいフリル基を表し、
Ｗ¹は、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基又はカルボキシル基を表し、
Ｚ¹は、炭素原子数１乃至１０のアルキレン基、炭素原子数１乃至１０のハロアルキレン基、スルホニル基、カルボニル基、アミド基又は酸素原子を表し、
Ｖ²及びＶ³は、アルカリ可溶性基を表す。なお、○は結合手を表す。）
第７観点として、前記Ｖ²及びＶ³が、それぞれ独立して、ヒドロキシ基又はカルボキシル基を表す、第６観点に記載のディスプレイ基板用樹脂組成物に関する。
第８観点として、前記Ｒ⁴乃至Ｒ⁹が水素原子を表す、第７観点に記載のディスプレイ基板用樹脂組成物に関する。
第９観点として、前記Ｙ¹が下記式（７）で表される構造である、第１観点乃至第８観点のうちいずれか１つに記載のディスプレイ基板用樹脂組成物に関する。

（式中、
Ｒ¹⁰乃至Ｒ¹³は、それぞれ独立して、水素原子、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基、Ｗ¹で置換されていてもよいフェニル基、Ｗ¹で置換されていてもよいナフチル基、Ｗ¹で置換されていてもよいチエニル基又はＷ¹で置換されていてもよいフリル基を表し、
Ｗ¹は、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基又はカルボキシル基を表し、
ｌは、１乃至３の整数を表す。なお、○は結合手を表す。）
第１０観点として、前記Ｒ¹⁰乃至Ｒ¹³が、それぞれ独立して、水素原子、ハロゲン原子、炭素原子数１乃至１０のアルキル基、又は炭素原子数１乃至１０のアルコキシ基を表す、第９観点に記載のディスプレイ基板用樹脂組成物に関する。
第１１観点として、前記Ｒ¹⁰乃至Ｒ¹³が、それぞれ独立して、水素原子、ハロゲン原子、炭素原子数１乃至３のアルキル基、又は炭素原子数１乃至３のアルコキシ基を表し、かつｌが１又は２を表す、第１０観点に記載のディスプレイ基板用樹脂組成物に関する。
第１２観点として、前記Ｒ¹⁰乃至Ｒ¹³が水素原子を表す、第１１観点に記載のディスプレイ基板用樹脂組成物に関する。
第１３観点として、前記Ｘ¹が下記式（８）で表される構造である、第１観点乃至第１２観点のうちいずれか１つに記載のディスプレイ基板用樹脂組成物に関する。

（式中、
Ｒ¹⁴乃至Ｒ²³は、それぞれ独立して、水素原子、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基、カルボキシル基、Ｗ¹で置換されていてもよいフェニル基、Ｗ¹で置換されていてもよいナフチル基、Ｗ¹で置換されていてもよいチエニル基又はＷ¹で置換されていてもよいフリル基を表し、
Ｗ¹は、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基又はカルボキシル基を表し、
Ｚ²及びＺ³は、それぞれ独立して、−ＮＨ−、−ＮＺ⁴−又は酸素原子を表し、
Ｚ⁴は、炭素原子数１乃至１０のアルキル基を表し、
ｐは、１又は２の整数を表す。なお、○は結合手を表す。）
第１４観点として、前記Ｒ¹⁴乃至Ｒ²³が水素原子を表す、第１３観点に記載のディスプレイ基板用樹脂組成物に関する。
第１５観点として、前記式（１）中のｎと前記式（３）中のｍがｎ／ｍ＝７０／３０乃至９９／１である、第１観点乃至第１４観点のうちいずれか１つに記載のディスプレイ基板用樹脂組成物に関する。
第１６観点として、前記式（２）中のｎと前記式（４）中のｍがｎ／ｍ＝７０／３０乃至９９／１である、第１観点乃至第１４観点のうちいずれか１つに記載のディスプレイ基板用樹脂組成物に関する。
第１７観点として、さらに架橋剤を含む、第１観点乃至第１６観点のうちいずれか１つに記載のディスプレイ基板用樹脂組成物に関する。
第１８観点として、前記架橋剤が２つ以上のエポキシ基を有し、かつ、１つ以上の芳香族基を有する化合物である、第１７観点に記載のディスプレイ基板用樹脂組成物に関する。
第１９観点として、前記架橋剤が６つ以下のエポキシ基を有する化合物であって、かつ該化合物はエポキシ基と芳香族基とを結合する炭素原子数１乃至１０のアルキレン基を有する、第１８観点に記載のディスプレイ基板用樹脂組成物に関する。
第２０観点として、前記ポリアミック酸又はポリイミド１００質量部に対して、前記架橋剤が２０質量部以下である、第１７観点乃至第１９観点のうちいずれか１つに記載のディスプレイ基板用樹脂組成物に関する。
第２１観点として、第１観点乃至第２０観点のうちいずれか１つに記載のディスプレイ基板用樹脂組成物が少なくとも１種の溶剤に溶解していることを特徴とする、ワニスに関する。
第２２観点として、第２１観点に記載のワニスを用いて２３０度以上で焼成することにより得られる、硬化膜に関する。
第２３観点として、基板上に第２２観点に記載の硬化膜からなる層を少なくとも一層備える、構造体に関する。
第２４観点として、下記式（１）で表される構造単位及び式（３）で表される構造単位を含むポリアミック酸に関する。

［式（１）及び式（３）中、
Ｘ¹は芳香族基と２つ以上のカルボニル基を有する４価の有機基を表し、
Ｙ¹は２価の有機基を表し、
Ｙ²はアルカリ可溶性基を有する２価の有機基を表し、
ｎ及びｍは自然数を表す。］
第２５観点として、下記式（２）で表される構造単位及び式（４）で表される構造単位を含むポリイミドに関する。

［式（２）及び式（４）中、
Ｘ¹は芳香族基と２つ以上のカルボニル基を有する４価の有機基を表し、
Ｙ¹は２価の有機基を表し、
Ｙ²はアルカリ可溶性基を有する２価の有機基を表し、
ｎ及びｍは自然数を表す。］
第２６観点として、第２５観点に記載のポリイミドからなるディスプレイ用基板に関する。That is, as a first aspect, the present invention provides a polyamic acid containing a structural unit represented by the following formula (1) and a structural unit represented by the formula (3), or a structural unit represented by the following formula (2) and It is related with the resin composition for display substrates containing the polyimide containing the structural unit represented by Formula (4).

[In Formula (1) thru | or Formula (4),
X ¹ represents a tetravalent organic group having an aromatic group and two or more carbonyl groups,
Y ¹ represents a divalent organic group,
Y ² represents a divalent organic group having an alkali-soluble group,
n and m represent natural numbers. ]
As a second aspect, the Y ² is a structure represented by the following formula (5) relates to a display substrate resin composition according to the first aspect.

(Where
R ^{1 to} R ³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a nitro group. , formyl group, cyano group, phenyl group which may be substituted with W ^1, be substituted with W ¹ optionally substituted by a naphthyl group, W ¹ which may be a thienyl group, or W ¹ substituted with Represents a good furyl group,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
V ¹ represents an alkali-soluble group,
k represents an integer of 1 to 3. In addition, (circle) represents a bond. )
As a third aspect, the present invention relates to the display substrate resin composition according to the second aspect, in which the V ¹ represents a hydroxy group or a carboxyl group.
As a fourth aspect, V ¹ represents a hydroxy group, and R ^{1 to} R ³ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 3 carbon atoms, or 1 carbon atom. It relates to the resin composition for display substrates as described in the 3rd viewpoint showing the thru | or 3 alkoxy group.
As a fifth aspect, the present invention relates to the resin composition for display substrates according to the fourth aspect, in which R ^{1 to} R ³ represent a hydrogen atom and k represents 2.
As a sixth aspect, the present invention relates to the display substrate resin composition according to the first aspect, wherein Y ² is a structure represented by the following formula (6).

(Where
R ^{4 to} R ⁹ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a nitro group. , formyl group, cyano group, phenyl group which may be substituted with W ^1, be substituted with W ¹ optionally substituted by a naphthyl group, W ¹ which may be a thienyl group, or W ¹ substituted with Represents a good furyl group,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
Z ¹ represents an alkylene group having 1 to 10 carbon atoms, a haloalkylene group having 1 to 10 carbon atoms, a sulfonyl group, a carbonyl group, an amide group or an oxygen atom,
V ² and V ³ represent an alkali-soluble group. In addition, (circle) represents a bond. )
As a seventh aspect, the present invention relates to the resin composition for a display substrate according to the sixth aspect, wherein V ² and V ³ each independently represent a hydroxy group or a carboxyl group.
As an eighth aspect, the present invention relates to the resin composition for a display substrate according to the seventh aspect, wherein R ^{4 to} R ⁹ represent hydrogen atoms.
As a ninth aspect, the present invention relates to the display substrate resin composition according to any one of the first aspect to the eighth aspect, wherein Y ¹ is a structure represented by the following formula (7).

(Where
R ^{10 to} R ¹³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a nitro group. , formyl group, cyano group, phenyl group which may be substituted with W ^1, be substituted with W ¹ optionally substituted by a naphthyl group, W ¹ which may be a thienyl group, or W ¹ substituted with Represents a good furyl group,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
l represents an integer of 1 to 3. In addition, (circle) represents a bond. )
As a tenth aspect, the ninth aspect, wherein R ^{10 to} R ¹³ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. It relates to the resin composition for display substrates as described in above.
As an eleventh aspect, R ^{10 to} R ¹³ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and l is The present invention relates to a resin composition for a display substrate according to the tenth aspect, which represents 1 or 2.
As a twelfth aspect, the present invention relates to the resin composition for a display substrate according to the eleventh aspect, wherein R ^{10 to} R ¹³ represent a hydrogen atom.
As a thirteenth aspect, the present invention relates to the display substrate resin composition according to any one of the first aspect to the twelfth aspect, wherein X ¹ is a structure represented by the following formula (8).

(Where
R ^{14 to} R ²³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, or a halogen atom. , nitro group, formyl group, cyano group, carboxyl group, W ¹ with an optionally substituted phenyl group, W ¹ with an optionally substituted naphthyl group, W ¹ with an optionally substituted thienyl group or W Represents a furyl group optionally substituted by ¹ ,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
Z ² and Z ³ each independently represent —NH—, —NZ ⁴ — or an oxygen atom,
Z ⁴ represents an alkyl group having 1 to 10 carbon atoms,
p represents an integer of 1 or 2. In addition, (circle) represents a bond. )
As a fourteenth aspect, the present invention relates to the resin composition for display substrates according to the thirteenth aspect, in which R ^{14 to} R ²³ represent a hydrogen atom.
As a fifteenth aspect, any one of the first aspect to the fourteenth aspect, wherein n in the formula (1) and m in the formula (3) are n / m = 70/30 to 99/1. It relates to the resin composition for display substrates as described in above.
As a sixteenth aspect, any one of the first aspect to the fourteenth aspect, wherein n in the formula (2) and m in the formula (4) are n / m = 70/30 to 99/1. It relates to the resin composition for display substrates as described in above.
As a seventeenth aspect, the present invention relates to the display substrate resin composition according to any one of the first to sixteenth aspects, further including a crosslinking agent.
As an eighteenth aspect, the present invention relates to the resin composition for a display substrate according to the seventeenth aspect, in which the cross-linking agent is a compound having two or more epoxy groups and one or more aromatic groups.
As a nineteenth aspect, the cross-linking agent is a compound having 6 or less epoxy groups, and the compound has an alkylene group having 1 to 10 carbon atoms that bonds the epoxy group and the aromatic group. It is related with the resin composition for display substrates as described in a viewpoint.
As a twentieth aspect, the resin composition for a display substrate according to any one of the seventeenth aspect to the nineteenth aspect, wherein the crosslinking agent is 20 parts by mass or less with respect to 100 parts by mass of the polyamic acid or polyimide. About.
As a twenty-first aspect, the present invention relates to a varnish, wherein the display substrate resin composition according to any one of the first to twentieth aspects is dissolved in at least one solvent.
As a 22nd viewpoint, it is related with the cured film obtained by baking at 230 degree | times or more using the varnish as described in a 21st viewpoint.
As a 23rd viewpoint, it is related with a structure provided with at least one layer which consists of a cured film as described in a 22nd viewpoint on a board | substrate.
As a 24th viewpoint, it is related with the polyamic acid containing the structural unit represented by the following formula (1), and the structural unit represented by Formula (3).

[In Formula (1) and Formula (3),
X ¹ represents a tetravalent organic group having an aromatic group and two or more carbonyl groups,
Y ¹ represents a divalent organic group,
Y ² represents a divalent organic group having an alkali-soluble group,
n and m represent natural numbers. ]
As a 25th viewpoint, it is related with the polyimide containing the structural unit represented by the following structural unit represented by Formula (2), and Formula (4).

[In Formula (2) and Formula (4),
X ¹ represents a tetravalent organic group having an aromatic group and two or more carbonyl groups,
Y ¹ represents a divalent organic group,
Y ² represents a divalent organic group having an alkali-soluble group,
n and m represent natural numbers. ]
As a 26th viewpoint, it is related with the display substrate which consists of a polyimide as described in a 25th viewpoint.

  The resin composition for a display substrate of the present invention can form a useful cured film having an appropriate linear expansion coefficient and an appropriate flexibility. Therefore, the cured film can be used as a base film for flexible displays.

［式（１）乃至式（４）中、
Ｘ¹は芳香族基と２つ以上のカルボニル基を有する４価の有機基を表し、
Ｙ¹は２価の有機基を表し、
Ｙ²はアルカリ可溶性基を有する２価の有機基を表し、
ｎ及びｍは自然数を表す。］[Resin composition for display substrate]
The present invention is represented by a polyamic acid containing a structural unit represented by the following formula (1) and a structural unit represented by the formula (3), or a structural unit represented by the following formula (2) and the formula (4). The present invention relates to a resin composition for a display substrate containing polyimide containing a structural unit.

[In Formula (1) thru | or Formula (4),
X ¹ represents a tetravalent organic group having an aromatic group and two or more carbonyl groups,
Y ¹ represents a divalent organic group,
Y ² represents a divalent organic group having an alkali-soluble group,
n and m represent natural numbers. ]

［式（ａ）乃至式（ｄ）中、Ｘ¹、Ｙ¹及びＹ²は、それぞれ前記式（１）乃至式（４）における定義と同じ意味を表す。］Here, the polyamic acid containing the structural unit represented by the above formula (1) and the structural unit represented by the formula (3) means n structural units represented by the following formula (a) and m number of structural units. This means a compound comprising a structural unit represented by the following formula (b), wherein these (n + m) structural units are bonded in any order, and the structural unit represented by the above formula (2) and the formula (4) The polyimide containing a structural unit represented by n includes n structural units represented by the following formula (c) and m structural units represented by the following formula (d), and these (n + m) pieces of structural units are represented by A compound in which structural units are bonded in any order.
In addition, the polyamic acid containing the structural unit represented by the above formula (1) and the structural unit represented by the formula (3) is represented by the structural unit represented by the following formula (c) and the formula (d). Either or both of the structural units may be present in the molecule, and the polyimide containing the structural unit represented by the above formula (2) and the structural unit represented by the formula (4) is represented by the following formula (a): Either or both of the structural unit represented by formula (b) and the structural unit represented by formula (b) may be present in the molecule.

[In the formulas (a) to (d), X ¹ , Y ¹ and Y ² represent the same meanings as defined in the formulas (1) to (4), respectively. ]

The content of the polyamic acid or polyimide (when both are included) in the resin composition for a display substrate of the present invention is 8 to 99 based on the solid content of the resin composition. 9.9% by mass, preferably 40 to 99.9% by mass, and more preferably 80 to 99.9% by mass.
Here, solid content is the remaining component which removed the solvent from all the components of the resin composition for display substrates.

（式中、Ｘ¹は芳香族基と２つ以上のカルボニル基を有する４価の有機基を表す。）で表される少なくとも１種の酸二無水物と、下記式（１０）：
Ｈ₂Ｎ−Ｙ¹−ＮＨ₂ （１０）
（式中、Ｙ¹は２価の有機基を表す。）で表される少なくとも１種のジアミンと、下記式（１１）：
Ｈ₂Ｎ−Ｙ²−ＮＨ₂ （１１）
（式中、Ｙ²はアルカリ可溶性基を有する２価の有機基を表す。）で表される少なくとも１種のジアミンとを溶剤に溶解し、反応させることで得られる。The resin composition for a display substrate of the present invention contains polyamic acid or polyimide.
<Polyamic acid>
The polyamic acid contained in the display substrate resin composition of the present invention is obtained by polymerizing an acid anhydride component and a diamine component in a solvent.
The polyamic acid is represented by the following formula (9) in a known method, for example, in an inert gas atmosphere such as nitrogen:

(Wherein, X ¹ represents a tetravalent organic group having an aromatic group and two or more carbonyl groups), and the following formula (10):
_{^{H 2 N-Y 1 -NH 2}} (10)
(Wherein Y ¹ represents a divalent organic group) and at least one diamine represented by the following formula (11):
H ₂ N—Y ² —NH ₂ (11)
(In the formula, Y ² represents a divalent organic group having an alkali-soluble group.) At least one diamine represented by the formula ( ² ) is dissolved in a solvent and reacted.

  The reaction temperature at this time is −20 to 100 ° C., preferably 20 to 60 ° C. The reaction time is 1 to 72 hours.

  In the present invention, the polyamic acid reaction solution as it is, or diluted or concentrated, or the polyamic acid recovered from the reaction solution by reprecipitation or the like is re-dissolved or dispersed in an appropriate solvent to obtain a resin composition for a display substrate. Can be used. The solvent used for dilution, re-dissolution or dispersion is not particularly limited as long as it can dissolve or disperse the obtained polyamic acid. For example, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2- Pyrrolidone, N-vinyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, 3-methoxy-N, N-dimethylpropylamide, 3-ethoxy-N, N-dimethylpropylamide, 3- Propoxy-N, N-dimethylpropylamide, 3-isopropoxy-N, N-dimethylpropylamide, 3-butoxy-N, N-dimethylpropylamide, 3-sec-butoxy-N, N-dimethylpropylamide, 3 -Tert-butoxy-N, N-dimethylpropylamide, γ-butyrolactone, etc.These solvents may be used alone or in combination of two or more.

（式中、
Ｒ¹⁴乃至Ｒ²³は、それぞれ独立して、水素原子、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基、カルボキシル基、Ｗ¹で置換されていてもよいフェニル基、Ｗ¹で置換されていてもよいナフチル基、Ｗ¹で置換されていてもよいチエニル基又はＷ¹で置換されていてもよいフリル基を表し、
Ｗ¹は、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基又はカルボキシル基を表し、
Ｚ²及びＺ³は、それぞれ独立して、−ＮＨ−、−ＮＺ⁴−又は酸素原子を表し、
Ｚ⁴は、炭素原子数１乃至１０のアルキル基を表し、
ｐは、１又は２の整数を表す。なお、○は結合手を表す。）Table Examples of the acid dianhydride represented by the structural dianhydride preferably represented by X ¹ is represented by the following formula (8), X ¹ is the following formula (8-1) by the formula (9) Particularly preferred are acid dianhydrides having the structure

(Where
R ^{14 to} R ²³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, or a halogen atom. , nitro group, formyl group, cyano group, carboxyl group, W ¹ with an optionally substituted phenyl group, W ¹ with an optionally substituted naphthyl group, W ¹ with an optionally substituted thienyl group or W Represents a furyl group optionally substituted by ¹ ,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
Z ² and Z ³ each independently represent —NH—, —NZ ⁴ — or an oxygen atom,
Z ⁴ represents an alkyl group having 1 to 10 carbon atoms,
p represents an integer of 1 or 2. In addition, (circle) represents a bond. )

Examples of the acid dianhydride represented by the formula (9) include p-phenylenebis (trimellitic acid monoester anhydride) and 2-methyl-1,4-phenylenebis (trimellitic acid monoester). Anhydride), 2,5-dimethyl-1,4-phenylenebis (trimellitic acid monoester anhydride), 2,3,5,6-tetramethyl-1,4-phenylenebis (trimellitic acid monoester anhydride) Product), 2-trifluoromethyl-1,4-phenylenebis (trimellitic acid monoester anhydride), 2,5-ditrifluoromethyl-1,4-phenylenebis (trimellitic acid monoester anhydride), 2 -Chloro-1,4-phenylenebis (trimellitic acid monoester anhydride), 2,5-dichloro-1,4-phenylenebis (trimellitic acid monoester) Water), 2-fluoro-1,4-phenylenebis (trimellitic acid monoester anhydride) and 2,5-difluoro-1,4-phenylenebis (trimellitic acid monoester anhydride), and N, N '-(1,4-phenylene) bis (1,3-dioxo-1,3-dihydrobenzofuran-5-carboxamide) and N, N'-(1,4-phenylene) bis (N-methyl-1, 3-dioxo-1,3-dihydrobenzofuran-5-carboxamide) and the like.
Among the acid dianhydrides, R ^{14 to} R ²³ in the formula (8) represent hydrogen atoms from the viewpoint that the cured film obtained from the resin composition of the present invention has a sufficiently low linear expansion coefficient. A compound in which Z ² and Z ³ represent an oxygen atom and p represents 1 or 2 is preferred, and from the viewpoint that the cured film obtained from the resin composition of the present invention has sufficiently high strength, 4,4′-biphenylbis (trimellitic acid) in which R ^{14 to} R ²³ in the formula (8) represent a hydrogen atom, Z ² and Z ³ represent an oxygen atom, and p represents 2. Monoester acid anhydride (following formula (12)) is preferred.

（式中、
Ｒ¹⁰乃至Ｒ¹³は、それぞれ独立して、水素原子、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基、Ｗ¹で置換されていてもよいフェニル基、Ｗ¹で置換されていてもよいナフチル基、Ｗ¹で置換されていてもよいチエニル基又はＷ¹で置換されていてもよいフリル基を表し、
Ｗ¹は、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基又はカルボキシル基を表し、
ｌは、１乃至３の整数を表す。なお、○は結合手を表す。）The diamine represented by the formula (10) is a diamine having a rigid and linear molecular structure from the viewpoint that the cured film obtained from the resin composition of the present invention has a sufficiently low linear expansion coefficient. It is preferable to do. Of these examples of the diamine represented by the formula (10), the structure diamine preferably represented by Y ¹ is the following formula (7), a structure in which Y ¹ is represented by the following formula (7-1) Certain diamines are particularly preferred.

(Where
R ^{10 to} R ¹³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a nitro group. , formyl group, cyano group, phenyl group which may be substituted with W ^1, be substituted with W ¹ optionally substituted by a naphthyl group, W ¹ which may be a thienyl group, or W ¹ substituted with Represents a good furyl group,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
l represents an integer of 1 to 3. In addition, (circle) represents a bond. )

In Formula (7), R ^{10 to} R ¹³ are preferably each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. From the viewpoint that the cured film obtained from the resin composition of the present invention has sufficiently high strength, R ^{10 to} R ¹³ are each independently a hydrogen atom, a halogen atom, or a carbon atom having 1 to 3 carbon atoms. An alkyl group or an alkoxy group having 1 to 3 carbon atoms and 1 is preferably 1 or 2, and the cured film obtained from the resin composition of the present invention has a sufficiently low linear expansion coefficient In view of the above, it is preferable that all of R ^{10 to} R ¹³ are hydrogen atoms.

Examples of the diamine represented by the formula (10) include p-phenylenediamine, m-phenylenediamine, 2-methyl-1,4-phenylenediamine, 2-trifluoromethyl-1,4-phenylenediamine, 2 -Methoxy-1,4-phenylenediamine, 2,5-dimethyl-1,4-phenylenediamine, 2,5-bis (trifluoromethyl) -1,4-phenylenediamine, 4,4'-diaminobenzanilide, 4-aminophenyl-4′-aminobenzoate, benzidine, 3,3′-dimethoxybenzidine, 3,3′-dichlorobenzidine, o-tolidine, m-tolidine, 2,2′-bis (trifluoromethyl) benzidine, 3,3′-bis (trifluoromethyl) benzidine, octafluorobenzidine, 3,3 ′, 5,5′-tetramethy Examples include benzidine, 2,2 ′, 5,5′-tetrachlorobenzidine, and among these, a cured film obtained from the resin composition of the present invention has a sufficiently high strength and a sufficiently low linear expansion coefficient. From the viewpoint of, p-phenylenediamine and m-phenylenediamine are particularly preferable.
These diamines can be used in combination of two or more.

（式中、
Ｒ¹乃至Ｒ³は、それぞれ独立して、水素原子、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基、Ｗ¹で置換されていてもよいフェニル基、Ｗ¹で置換されていてもよいナフチル基、Ｗ¹で置換されていてもよいチエニル基又はＷ¹で置換されていてもよいフリル基を表し、
Ｗ¹は、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基又はカルボキシル基を表し、
Ｖ¹は、アルカリ可溶性基を表し、
ｋは、１乃至３の整数を表す。なお、○は結合手を表す。）The diamine represented by the formula (11) uses a diamine having a rigid and linear molecular structure from the viewpoint that the cured film obtained from the resin composition of the present invention has a sufficiently low linear expansion coefficient. It is preferable to do. Of these examples of the diamine represented by the formula (11), the structure diamine preferably represented by Y ² is the following formula (5), a structure in which Y ² is represented by the following formula (5-1) Certain diamines are particularly preferred.

(Where
R ^{1 to} R ³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a nitro group. , formyl group, cyano group, phenyl group which may be substituted with W ^1, be substituted with W ¹ optionally substituted by a naphthyl group, W ¹ which may be a thienyl group, or W ¹ substituted with Represents a good furyl group,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
V ¹ represents an alkali-soluble group,
k represents an integer of 1 to 3. In addition, (circle) represents a bond. )

In the formula (5), V ¹ is preferably a hydroxy group or a carboxyl group.
In the formula (5), V ¹ represents a hydroxy group, and R ^{1 to} R ³ are each independently a hydrogen atom, a halogen atom, an alkyl group having 1 to 3 carbon atoms, or carbon. An alkoxy group having 1 to 3 atoms is preferable.
Furthermore, from the viewpoint that the cured film obtained from the resin composition of the present invention has a sufficiently high strength, in the above formula (5), k is preferably 2, and further from the resin composition of the present invention. From the viewpoint that the obtained cured film has a sufficiently low linear expansion coefficient, it is preferable that all of R ^{1 to} R ³ are hydrogen atoms.

  As the diamine represented by the formula (11), for example, 4,4'-diamino-3,3'-dihydroxybiphenyl, 3,3'-diamino-4,4'-dihydroxybiphenyl and the like are preferable.

（式中、
Ｒ⁴乃至Ｒ⁹は、それぞれ独立して、水素原子、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基、Ｗ¹で置換されていてもよいフェニル基、Ｗ¹で置換されていてもよいナフチル基、Ｗ¹で置換されていてもよいチエニル基又はＷ¹で置換されていてもよいフリル基を表し、
Ｗ¹は、炭素原子数１乃至１０のアルキル基、炭素原子数１乃至１０のハロアルキル基、炭素原子数１乃至１０のアルコキシ基、ヒドロキシ基、ハロゲン原子、ニトロ基、ホルミル基、シアノ基又はカルボキシル基を表し、
Ｚ¹は、炭素原子数１乃至１０のアルキレン基、炭素原子数１乃至１０のハロアルキレン基、スルホニル基、カルボニル基、アミド基又は酸素原子を表し、
Ｖ²及びＶ³は、アルカリ可溶性基を表す。なお、○は結合手を表す。）Moreover, as the diamine represented by the formula (11), Y ² can also be used diamine is a structure represented by the following formula (6).

(Where
R ^{4 to} R ⁹ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a nitro group. , formyl group, cyano group, phenyl group which may be substituted with W ^1, be substituted with W ¹ optionally substituted by a naphthyl group, W ¹ which may be a thienyl group, or W ¹ substituted with Represents a good furyl group,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
Z ¹ represents an alkylene group having 1 to 10 carbon atoms, a haloalkylene group having 1 to 10 carbon atoms, a sulfonyl group, a carbonyl group, an amide group or an oxygen atom,
V ² and V ³ represent an alkali-soluble group. In addition, (circle) represents a bond. )

In the formula (6), V ² and V ³ are preferably each independently a hydroxy group or a carboxyl group.

Examples of the diamine represented by the formula (11) in which Y ² is a structure represented by the formula (6) include bis (3-amino-4-hydroxyphenyl) sulfide (BSDA), bis (3- Amino-4-hydroxyphenyl) methane (BAPF), 2,2′-bis (3-amino-4-hydroxyphenyl) propane (BAPA), 3,3′-diamino-4,4′-dihydroxybenzophenone (AHPK) (3-amino-4-hydroxy) phenyl (3-amino-4-hydroxy) anilide (AHPA), 2,2'-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (AHF), 3, 3'-diamino-2,2'-dihydroxybiphenyl (2BP), bis (3-amino-4-hydroxyphenyl) ether (AHPE), etc. That.

  Although it does not specifically limit as a solvent used for the production | generation reaction of a polyamic acid, For example, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylformamide, N-methyl-2-pyrrolidone, hexamethyl Phosphoramide, dimethylsulfoxide, 3-methoxy-N, N-dimethylpropylamide, 3-ethoxy-N, N-dimethylpropylamide, 3-propoxy-N, N-dimethylpropylamide, 3-isopropoxy-N , N-dimethylpropylamide, 3-butoxy-N, N-dimethylpropylamide, 3-sec-butoxy-N, N-dimethylpropylamide, 3-tert-butoxy-N, N-dimethylpropylamide, γ-butyrolactone 1,3-dimethyl-2-imidazolidinone, 1,2-dimethyl Aprotic solvents such as xylene-bis (2-methoxyethyl) ether, tetrahydrofuran, 1,4-dioxane, picoline, pyridine, acetone, chloroform, toluene, xylene, and phenol, o-cresol, m-cresol, p- Examples include protic solvents such as cresol, o-chlorophenol, m-chlorophenol, and p-chlorophenol. These solvents may be used alone or in combination of two or more.

  In the above reaction, the ratio of the diamine component is such that the molar ratio of the diamine represented by the formula (10) and the diamine represented by the formula (11) is 70/30 to 99/1. From the viewpoint that the cured film obtained from the resin composition of the present invention has a sufficiently low linear expansion coefficient and a sufficiently high strength, it is more preferably 75/25 to 95/5.

  Moreover, in the said reaction, it is preferable that the ratio of an acid dianhydride component and a diamine component is acid dianhydride component / diamine component = 0.8 thru | or 1.2 by molar ratio. Similar to the normal polycondensation reaction, the closer the molar ratio is to 1, the higher the degree of polymerization of the polymer produced. When the degree of polymerization is too small, the strength of the polyimide cured film becomes insufficient, and when the degree of polymerization is too large, workability at the time of forming the polyimide cured film may be deteriorated.

  The weight average molecular weight of the produced polyamic acid is preferably 3,000 to 200,000 in terms of polystyrene in order to maintain the strength of the cured film obtained from the resin composition for display substrate containing polyamic acid. If the weight average molecular weight is less than 3,000, the resulting film may be brittle. On the other hand, if the weight average molecular weight exceeds 200,000, the viscosity of the polyamic acid varnish may be too high. This is because handling becomes difficult.

［式中、ｋ、ｌ及びｐは、それぞれ前記式（５）、（７）及び式（８）における定義と同じ意味を表す。］The relationship between the number n of structural units represented by formula (1) and the number m of structural units represented by formula (3) in the produced polyamic acid is preferably n / m = 70/30 to 99 / 1, more preferably 75/25 to 95/5.
In particular, from the viewpoint that the obtained cured film has a sufficiently low linear expansion coefficient and a sufficiently high strength, X ¹ is R ^{14 to} R ²³ are hydrogen atoms, and Z ² and Z ³ are oxygen. Structural unit represented by formula (1), which is a structure represented by formula (8) which is an atom, and Y ¹ is a structure represented by formula (7) wherein R ^{10 to} R ¹³ are hydrogen atoms (Structural unit represented by the following formula (1-1)) and X ¹ are structures represented by the formula (8) in which R ^{14 to} R ²³ are hydrogen atoms, and Z ² and Z ³ are oxygen atoms. Y ² is a structural unit represented by the formula (3), which is a structure represented by the formula (5) wherein R ^{1 to} R ³ are hydrogen atoms and V ¹ is a hydroxy group (the following formula ( The ratio of the structural unit represented by 3-1) is preferably the sum of both of the repeating units of the polyamic acid produced, preferably 70 mol% or more, more preferably Is 80 mol% or more, more preferably 85 mol% or more.

[Wherein, k, l and p represent the same meaning as defined in the formulas (5), (7) and (8), respectively. ]

［式中、ｋ、ｌ及びｐは、それぞれ前記式（５）、（７）及び式（８）における定義と同じ意味を表す。なお、○は結合手を表す。］When a resin composition for a display substrate is produced using the polyamic acid obtained by the above-described method, particularly when the resin composition is produced in the form of a varnish by dissolving or dispersing in a solvent, X ¹ is represented by the following formula (8 -2), wherein Y ¹ is a structure represented by the following formula (7-2) and the structural unit represented by formula (1) and X ¹ are represented by the following formula (8-2) ) And a polyamic acid containing a structural unit represented by formula (3) wherein Y ² is a structure represented by the following formula (5-2) is preferred (hereinafter referred to as configuration A), X ¹ is a structure represented by the following formula (8-3), and Y ¹ is a structural unit represented by the formula (1) which is a structure represented by the following formula (7-3) and X ¹ Is a structure represented by the following formula (8-3), and Y ² is a structure represented by the formula (3) which is a structure represented by the following formula (5-3). A polyamic acid containing a building unit is more preferable (hereinafter referred to as configuration B), X ¹ is a structure represented by the following formula (8-3) in which p is 2, and Y ¹ is 1 in the following. The structural unit represented by the formula (1) which is the structure represented by the formula (7-3) and X ¹ are structures represented by the following formula (8-3) in which p is 2, Y ² However, the polyamic acid containing the structural unit represented by the formula (3) which is a structure represented by the following formula (5-3) in which k is 2 is more preferable (hereinafter, configuration C).

[Wherein, k, l and p represent the same meaning as defined in the formulas (5), (7) and (8), respectively. In addition, (circle) represents a bond. ]

Further, under each of these preferable configurations (configurations A, B, or C), the number n of structural units represented by formula (1) and the number m of structural units represented by formula (3) are n / M = 70/30 to 99/1, preferably n / m = 75/25 to 95/5, and the structural unit represented by the above formula (1-1) and the above formula (3 The ratio of the structural unit represented by -1) is 70 mol% or more, preferably 80 mol% or more, more preferably 85 mol% or more in the repeating unit of the polyamic acid in the total of both, and The weight average molecular weight of the polyamic acid is preferably 3,000 to 200,000 (polystyrene conversion).
In addition, the polyamic acid containing the structural unit represented by Formula (1) and the structural unit represented by Formula (3) demonstrated above is also the object of this invention.

<Polyimide>
The polyimide contained in the resin composition for display substrates of the present invention can be obtained by subjecting the polyamic acid synthesized as described above to dehydration ring closure (thermal imidization) by heating. At this time, polyamic acid can be converted to imide in a solvent and used as a solvent-soluble polyimide. Moreover, the method of chemically ring-closing using a well-known dehydration ring-closing catalyst is also employable. The method by heating can be performed at an arbitrary temperature of 100 to 300 ° C., preferably 120 to 250 ° C. The chemical ring closure method can be performed, for example, in the presence of pyridine, triethylamine, and the like, and acetic anhydride, and the temperature at this time can be selected from -20 to 200 ° C. .

  In the present invention, the polyimide reaction solution is used as it is, or diluted or concentrated, or the polyimide recovered from the reaction solution by reprecipitation or the like is dissolved or dispersed in an appropriate solvent and used as a resin composition for a display substrate. be able to. The solvent used for dilution, re-dissolution or dispersion is not particularly limited as long as it can dissolve or disperse the obtained polyimide. For example, m-cresol, 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl -2-pyrrolidone, N-vinyl-2-pyrrolidone, N, N-dimethylacetamide, N, N-dimethylformamide, 3-methoxy-N, N-dimethylpropylamide, 3-ethoxy-N, N-dimethylpropylamide , 3-propoxy-N, N-dimethylpropylamide, 3-isopropoxy-N, N-dimethylpropylamide, 3-butoxy-N, N-dimethylpropylamide, 3-sec-butoxy-N, N-dimethylpropyl Amides, 3-tert-butoxy-N, N-dimethylpropylamide, γ-butyrolactone, etc. It is. These solvents may be used alone or in combination of two or more.

  The weight average molecular weight of the produced polyimide is preferably 3,000 to 200,000 in terms of polystyrene in order to maintain the strength of the cured film obtained from the resin composition for display substrate containing polyimide. If the weight average molecular weight is less than 3,000, the resulting film may become brittle, while if the weight average molecular weight exceeds 200,000, the viscosity of the polyimide varnish may be too high, and as a result, This is because handling becomes difficult.

［式中、ｋ、ｌ及びｐは、それぞれ前記式（５）、（７）及び式（８）における定義と同じ意味を表す。］The relationship between the number n of structural units represented by formula (2) and the number m of structural units represented by formula (4) in the polyimide produced is preferably n / m = 70/30 to 99/1. More preferably, it is 75/25 to 95/5.
In particular, from the viewpoint that the obtained cured film has a sufficiently low linear expansion coefficient and a sufficiently high strength, X ¹ is R ^{14 to} R ²³ are hydrogen atoms, and Z ² and Z ³ are oxygen. A structural unit represented by Formula (2), which is a structure represented by Formula (8) which is an atom, and Y ¹ is a structure represented by Formula (7) in which R ^{10 to} R ¹³ are hydrogen atoms. (Structural unit represented by the following formula (2-1)) and X ¹ are structures represented by the formula (8) in which R ^{14 to} R ²³ are hydrogen atoms, and Z ² and Z ³ are oxygen atoms. Y ² is a structural unit represented by the formula (4) which is a structure represented by the formula (5) in which R ^{1 to} R ³ are hydrogen atoms and V ¹ is a hydroxy group (the following formula ( The ratio of the structural unit represented by 4-1) is preferably 70 mol% or more, more preferably 8 in the total repeating unit of the polyimide formed. It is 0 mol% or more, more preferably 85 mol% or more.

[Wherein, k, l and p represent the same meaning as defined in the formulas (5), (7) and (8), respectively. ]

When a resin composition for a display substrate is produced using the polyimide obtained by the above-described method, particularly when the resin composition is produced in the form of a varnish by dissolving or dispersing in a solvent, X ¹ represents the above formula (8- 2), wherein Y ¹ is a structure represented by the above formula (7-2) and the structural unit represented by the formula (2) and X ¹ are represented by the above formula (8-2). And a polyimide containing a structural unit represented by the formula (4) wherein Y ² is a structure represented by the above formula (5-2) (hereinafter referred to as configuration D), X ¹ Is a structure represented by the above formula (8-3), and Y ¹ is a structure represented by the above formula (7-3) and the structural unit represented by the formula (2) and X ¹ are The structural unit represented by the formula (4) is a structure represented by the above formula (8-3), and Y ² is a structure represented by the above formula (5-3). The polyimide containing is more preferable (hereinafter referred to as configuration E), X ¹ is a structure represented by the above formula (8-3) in which p is 2, and Y ¹ is the above formula (7− in which l is 1). 3) is a structure represented by the formula (2) which is a structure represented by 3), and X ¹ is a structure represented by the above formula (8-3) in which p is 2, Y ² is k The polyimide containing the structural unit represented by the formula (4) which is the structure represented by the above formula (5-3) which is 2 is more preferable (hereinafter referred to as configuration F).

Further, under these preferable configurations (configurations D, E, or F), the number n of structural units represented by formula (2) and the number m of structural units represented by formula (4) are n / M = 70/30 to 99/1, preferably n / m = 75/25 to 95/5, and the structural unit represented by the above formula (2-1) and the above formula (4) The proportion of the structural unit represented by -1) is 70 mol% or more, preferably 80 mol% or more, more preferably 85 mol% or more in the repeating unit of polyimide in the total of both, and polyimide Is preferably 3,000 to 200,000 (in terms of polystyrene).
In addition, the polyimide containing the structural unit represented by Formula (2) and the structural unit represented by Formula (4) demonstrated above is also the object of this invention.

  The resin composition for display substrates of the present invention comprises a structural unit represented by the above formula (1) and a polyamic acid containing a structural unit represented by the formula (3), a structural unit represented by the above formula (2), and Both of the polyimide containing the structural unit represented by the formula (4) may be included.

  The resin composition for a display substrate of the present invention contains a solvent, and preferably the polyamic acid or polyimide is dissolved or uniformly dispersed, and more preferably the polyamic acid or polyimide is dissolved in the solvent. Examples of such solvents include the solvents described in paragraph [0014].

Moreover, the resin composition for display substrates of this invention can contain a crosslinking agent (henceforth a crosslinkable compound).
<Crosslinking agent>
The crosslinkable compound has a group capable of reacting with an organic group contained in at least one of polyamic acid or polyimide in the step of converting the coating film obtained using the resin composition for display substrate into a cured film. If it is a compound, it will not specifically limit. Examples of such a compound include a compound containing two or more epoxy groups, a melamine derivative, a benzoguanamine derivative, or a group in which a hydrogen atom of an amino group is substituted with a methylol group, an alkoxymethyl group, or both. Examples include glycoluril. The melamine derivative and benzoguanamine derivative may be a dimer or a trimer, or may be a mixture arbitrarily selected from a monomer, a dimer and a trimer. These melamine derivatives and benzoguanamine derivatives preferably have an average of 3 or more and less than 6 methylol groups or alkoxymethyl groups per one triazine ring.
Moreover, you may use the crosslinking agent used for this invention individually or in combination of 2 or more types.

Although the specific example of a crosslinkable compound is given to the following, it is not limited to this.
Examples of the compound containing two or more epoxy groups include Epolide GT-401, Epolide GT-403, Epolide GT-301, Epolide GT-302, Celoxide 2021, and Celoxide 3000 (manufactured by Daicel Chemical Industries, Ltd.). Epoxy compounds having a cyclohexene structure; bisphenol A type epoxy compounds such as Epicoat 1001, Epicoat 1002, Epicoat 1003, Epicoat 1004, Epicoat 1007, Epicoat 1009, Epicoat 1010, Epicoat 828 (above, manufactured by Japan Epoxy Resins Co., Ltd.); Bisphenol F type epoxy compound such as 807 (manufactured by Japan Epoxy Resin Co., Ltd.); Epicoat 152, Epicoat 154 (above, manufactured by Japan Epoxy Resin Co., Ltd.), EPP 201, EPPN202 (above, Nippon Kayaku Co., Ltd.) and other phenol novolac type epoxy compounds; ECON-102, ECON-103S, ECON-104S, ECON-1020, ECON-1025, ECON-1027 (above, Nippon Kayaku) Cresol novolak type epoxy compounds such as Yakuhin Co., Ltd., Epicoat 180S75 (made by Japan Epoxy Resin Co., Ltd.); naphthalene type epoxy compounds such as V8000-C7 (made by DIC Corporation); Denacol EX-252 (Nagase Chem) Manufactured by Tex Co., Ltd.), CY175, CY177, CY179, Araldite CY-182, Araldite CY-192, Araldite CY-184 (above, manufactured by BASF), Epicron 200, Epicron 400 (above, manufactured by DIC Corporation), Epicote 871 Alicyclic epoxy compounds such as Epicoat 872 (above, Japan Epoxy Resin Co., Ltd.), ED-5661, ED-5661 (above, Celanese Coating Co., Ltd.); Denacol EX-611, Denacol EX-612, Denacol EX-614, Denacol EX-622, Denacol EX-411, Denacol EX-512, Denacol EX-522, Denacol EX-421, Denacol EX-313, Denacol EX-314, Denacol EX-312 (above, Nagase ChemteX Aliphatic polyglycidyl ether compounds such as those manufactured by KK

As the melamine derivative, benzoguanamine derivative, or glycoluril having a group in which the hydrogen atom of the amino group is substituted with a methylol group, an alkoxymethyl group, or both, an average of 3.7 methoxymethyl groups are substituted per triazine ring. MX-750, MW-30 substituted with an average of 5.8 methoxymethyl groups per triazine ring (above, manufactured by Sanwa Chemical Co., Ltd.); Cymel 300, Cymel 301, Cymel 303, Cymel 350 Methoxymethylated melamine such as Cymel 370, Cymel 771, Cymel 325, Cymel 327, Cymel 703, Cymel 712, etc .; Mela Butylmethylated melamines such as Cymel 506 and Cymel 508; carboxyl group-containing methoxymethylated isobutoxymethylated melamines such as Cymel 1141; methoxymethylated ethoxymethylated benzoguanamines such as Cymel 1123; Methoxymethylated butoxymethylated benzoguanamine; butoxymethylated benzoguanamine such as Cymel 1128; carboxyl-containing methoxymethylated ethoxymethylated benzoguanamine such as Cymel 1125-80; butoxymethylated glycoluril such as Cymel 1170; Cymel 1172 Such as methylolated glycoluril (manufactured by Mitsui Cyanamid Co., Ltd.).
Moreover, content of the crosslinking agent in the resin composition for display substrates of this invention is 100 masses of polyamic acid or polyimide (when both are included, polyamic acid and polyimide) from a viewpoint of improving the storage stability of the resin composition. From the viewpoint that the cured film obtained from the resin composition of the present invention has a sufficiently low linear expansion coefficient, 15 parts by mass or less is more preferable.

[Varnish and cured film]
The specific method of forming a cured film using the resin composition for display substrates of this invention is as follows.
First, the polyamic acid containing the structural unit represented by the above formula (1) and the structural unit represented by the formula (3), or the structural unit represented by the above formula (2) and the structure represented by the formula (4) A resin composition is prepared in the form of a varnish (film forming material) by dissolving or dispersing polyimide containing units in a solvent. Or the resin composition of the form of a varnish is prepared by using the reaction solution of the polyamic acid or polyimide demonstrated above as it is, or diluting or concentrating.
Then, the varnish is cast on a substrate by a cast coating method, a spin coating method, a blade coating method, a dip coating method, a roll coating method, a bar coating method, a die coating method, an ink jet method, a printing method (letter plate, intaglio plate, planographic plate, screen printing, etc. ) To obtain a coating film. And the cured film is formed by baking the obtained coating film with a hotplate, oven, etc. FIG.
The baking temperature for forming the cured film is usually 100 to 400 ° C., preferably 100 to 350 ° C. By this baking treatment, the solvent evaporates and the polyamic acid is dehydrated and closed (imidized) to become polyimide. . At this time, the temperature may be changed in two or more steps for the purpose of developing a higher uniform film forming property or causing the reaction to proceed on the substrate.
Examples of the substrate to be used include plastic (polycarbonate, polymethacrylate, polystyrene, polyester, polyolefin, epoxy, melamine, triacetyl cellulose, ABS, AS, norbornene resin, etc.), metal, wood, paper, glass, slate, etc. Can be mentioned.

The solvent used in the form of the varnish is not particularly limited as long as it dissolves or disperses the polyamic acid or the polyimide, and examples thereof include a solvent used in the reaction for producing the polyamic acid. These solvents may be used alone or in combination of two or more.
In addition, the concentration of dissolving or dispersing polyamic acid or polyimide (when both are included, polyamic acid and polyimide; the same shall apply hereinafter) in the solvent is usually the total mass (total mass) of the polyamic acid or polyimide and the solvent. It is 5 to 40% by mass, preferably 5 to 20% by mass from the viewpoint of improving the storage stability of the resin composition, and more preferably 5 to 15% by mass from the viewpoint of improving the coatability of the varnish. is there.
Although the thickness of the cured film formed from the resin composition for display substrates is not specifically limited, Usually, 1-50 micrometers, Preferably it is 5-40 micrometers.

ＴＡＨＱ：ｐ−フェニレンビス（トリメリット酸モノエステル酸無水物）（マナック（株）製）（下記式（１３））

＜ジアミン＞
ＰＤＡ：ｐ−フェニレンジアミン（東京化成（株）製）
ＨＡＢ：４，４’−ジアミノ−３，３’−ジヒドロキシビフェニル（和歌山精化工業（株）製）
４ＢＰ：３，３’−ジアミノ−４，４’−ジヒドロキシビフェニル（和歌山精化工業（株）製）
＜架橋剤＞
Ｖ８０００−Ｃ７：ナフタレン型エポキシ化合物（ＤＩＣ（株）製）
＜溶剤＞
ＮＭＰ：Ｎ−メチル−２−ピロリドンEXAMPLES Hereinafter, although an Example is given and this invention is demonstrated more concretely, this invention is not limited to the following Example.
[Abbreviations used in Examples]
The meanings of the abbreviations used in the following examples are as follows.
<Acid dianhydride>
BP-TME: 4,4′-biphenylbis (trimellitic acid monoester anhydride) (manufactured by Honshu Chemical Industry Co., Ltd.) (formula (12) below)

TAHQ: p-phenylenebis (trimellitic acid monoester anhydride) (manac Co., Ltd.) (formula (13) below)

<Diamine>
PDA: p-phenylenediamine (manufactured by Tokyo Chemical Industry Co., Ltd.)
HAB: 4,4′-diamino-3,3′-dihydroxybiphenyl (Wakayama Seika Kogyo Co., Ltd.)
4BP: 3,3′-diamino-4,4′-dihydroxybiphenyl (Wakayama Seika Kogyo Co., Ltd.)
<Crosslinking agent>
V8000-C7: naphthalene type epoxy compound (manufactured by DIC Corporation)
<Solvent>
NMP: N-methyl-2-pyrrolidone

[Measurement of number average molecular weight and weight average molecular weight]
The weight average molecular weight (hereinafter abbreviated as Mw) and the molecular weight distribution of the polymer were measured using a GPC apparatus (Shodex [registered trademark] columns KF803L and KF805L) manufactured by JASCO Corporation, with dimethylformamide as the elution solvent at a flow rate of 1 mL / min The column temperature was measured at 50 ° C. In addition, Mw was made into the polystyrene conversion value.

<Synthesis Example P1: Synthesis of polyamic acid (P1)>
16.7 g (0.154 mol) of PDA and 8.34 g (0.039 mol) of HAB were dissolved in 700 g of NMP. After adding 101 g (0.189 mol) of BP-TME, 74 g of NMP was added again. The reaction was performed at 23 ° C. for 24 hours under a nitrogen atmosphere. The obtained polymer had Mw of 129,000 and a molecular weight distribution of 2.5.

<Synthesis Example P2: Synthesis of polyamic acid (P2)>
PDA 19.1 g (0.156 mol) and 4BP 4.24 g (0.039 mol) were dissolved in NMP 700 g, BP-TME 102 g (0.192 mol) was added, NMP 74 g was added again, The reaction was performed at 23 ° C. for 24 hours under a nitrogen atmosphere. Mw of the obtained polymer was 136,300, and molecular weight distribution was 2.4.

<Synthesis Example P3: Synthesis of polyamic acid (P3)>
30.4 g (0.281 mol) of PDA and 6.75 g (0.031 mol) of 4BP were dissolved in 700 g of NMP, 142 g (0.306 mol) of TAHQ was added, 20 g of NMP was added again, and nitrogen atmosphere was added. The reaction was allowed to proceed at 23 ° C. for 24 hours. Mw of the obtained polymer was 119,600 and molecular weight distribution was 3.5.

<Comparative Example HP1: Synthesis of polyamic acid (HP1)>
Dissolve 22.7 g (0.210 mol) of PDA in 700 g of NMP, add 94.3 g (0.205 mol) of TAHQ, add 83 g of NMP again, and react at 23 ° C. for 24 hours in a nitrogen atmosphere. It was. Mw of the obtained polymer was 103,300 and molecular weight distribution was 3.8.

<Comparative Example HP2: Synthesis of polyamic acid (HP2)>
35.1 g (0.162 mol) of HAB was dissolved in 800 g of NMP, 84.9 g (0.158 mol) of BP-TME was added, and then 80 g of NMP was added again, and the reaction was continued at 23 ° C. for 24 hours under a nitrogen atmosphere. Reacted. The obtained polymer had Mw of 148,400 and a molecular weight distribution of 2.5.

<Comparative Example HP3: Synthesis of polyamic acid (HP3)>
38.8 g (0.180 mol) of HAB was dissolved in 800 g of NMP, 81.0 g (0.176 mol) of TAHQ was added, and then 80 g of NMP was added again and reacted at 23 ° C. for 24 hours in a nitrogen atmosphere. It was. Mw of the obtained polymer was 127,600 and molecular weight distribution was 2.8.

<Comparative Example HP4: Synthesis of polyamic acid (HP4)>
48.8 g (0.180 mol) of 4BP was dissolved in 800 g of NMP, 81.0 g (0.176 mol) of TAHQ was added, and then 80 g of NMP was added again and reacted at 23 ° C. for 24 hours in a nitrogen atmosphere. It was. Mw of the obtained polymer was 127,600 and molecular weight distribution was 2.8.

<Sample preparation: Varnish>
According to the composition shown in Table 1, NMP is mixed as a polymer solution, a crosslinking agent, and a solvent, and stirred at room temperature (approximately 23 ° C.) for 6 hours or more to obtain a uniform solution, whereby a resin composition for a display substrate (varnish) Was prepared.

<Evaluation of coating film and linear expansion coefficient>
The resin composition for display substrates (varnish) prepared above was evaluated by the following method. The evaluation results are shown in Table 2.
[Pre-cure film thickness and peeling method]
Each of the resin compositions for display substrates (varnish) shown in Table 1 was applied on a 100 mm × 100 mm glass substrate using a bar coater (step difference 250 μm), and the temperature was 110 degrees for 10 minutes, the temperature was 250 degrees for 30 minutes, Baked in an oven at 300 degrees for 30 minutes. The film thickness of the obtained coating film was measured using a contact-type film thickness measuring device (Dektak 3ST manufactured by ULVAC). Then, it left still in the 70 degree pure water in a 1L beaker for every glass substrate, and peeled the film.

[Linear expansion coefficient]
A 20 mm × 5 mm strip is prepared from the film obtained above, and the temperature is raised from 50 to 400 degrees at a rate of 5 degrees / minute using TMA-4000SA (manufactured by Bruker AXS Co., Ltd.). After cooling, the linear expansion coefficient from 50 degrees to 400 degrees was measured again.

  As shown in Table 2, it was found that the thin film obtained from the resin composition for a display substrate of the present invention has an appropriate linear expansion coefficient and an appropriate flexibility.

Claims (19)

A structural unit represented by the following formula (1) and a polyamic acid containing a structural unit represented by the formula (3) or a structural unit represented by the following formula (2) and a structural unit represented by the formula (4) The resin composition for display substrates containing the containing polyimide.

[In Formula (1) thru | or Formula (4),
X ¹ is the following formula (8)

(Where
R ^{14 to} R ²³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, or a halogen atom. , nitro group, formyl group, cyano group, carboxyl group, W ¹ with an optionally substituted phenyl group, W ¹ with an optionally substituted naphthyl group, W ¹ with an optionally substituted thienyl group or W Represents a furyl group optionally substituted by ¹ ,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
Z ² and Z ³ each independently represent —NH—, —NZ ⁴ — or an oxygen atom,
Z ⁴ represents an alkyl group having 1 to 10 carbon atoms,
p represents an integer of 1 or 2. In addition, (circle) represents a bond. )
Y ¹ is the following formula (7)

(Where
R ^{10 to} R ¹³ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms,
l represents an integer of 1 to 3. In addition, (circle) represents a bond. )
Y ² is the following formula (5)

(Where
R ^{1 to} R ³ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a nitro group. , formyl group, cyano group, phenyl group which may be substituted with W ^1, be substituted with W ¹ optionally substituted by a naphthyl group, W ¹ which may be a thienyl group, or W ¹ substituted with Represents a good furyl group,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
V ¹ represents an alkali-soluble group,
k represents an integer of 1 to 3. In addition, (circle) represents a bond. ) Or a structure represented by the following formula (6)

(Where
R ^{4 to} R ⁹ are each independently a hydrogen atom, an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a halogen atom, or a nitro group. , formyl group, cyano group, phenyl group which may be substituted with W ^1, be substituted with W ¹ optionally substituted by a naphthyl group, W ¹ which may be a thienyl group, or W ¹ substituted with Represents a good furyl group,
W ¹ is an alkyl group having 1 to 10 carbon atoms, a haloalkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, a hydroxy group, a halogen atom, a nitro group, a formyl group, a cyano group, or a carboxyl group. Represents a group,
Z ¹ represents an alkylene group having 1 to 10 carbon atoms, a haloalkylene group having 1 to 10 carbon atoms, a sulfonyl group, a carbonyl group, an amide group or an oxygen atom,
V ² and V ³ represent an alkali-soluble group. In addition, (circle) represents a bond. )
n and m represent natural numbers. ] The resin composition for display substrates according to claim 1 , wherein V ¹ represents a hydroxy group or a carboxyl group. V ¹ represents a hydroxy group, and R ^{1 to} R ³ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms. The resin composition for display substrates according to claim 2 , which represents The resin composition for a display substrate according to claim 3 , wherein R ^{1 to} R ³ represent a hydrogen atom, and k represents 2. The resin composition for display substrates according to claim 1 , wherein V ² and V ³ each independently represent a hydroxy group or a carboxyl group. The resin composition for a display substrate according to claim 5 , wherein R ^{4 to} R ⁹ represent a hydrogen atom. R ^{10 to} R ¹³ each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and l represents 1 or 2. The resin composition for display substrates of any one of Claims 1 thru | or 6 . The resin composition for display substrates according to claim 7 , wherein R ^{10 to} R ¹³ represent a hydrogen atom. The resin composition for display substrates according to claim 8 , wherein R ^{14 to} R ²³ represent a hydrogen atom. Wherein a formula (1) the formula (3) m is n / m = 70/30 to in the n in 99/1, display board as claimed in any one of claims 1 to 9 Resin composition. Wherein a formula (2) n in the formula (4) m is n / m = 70/30 to in in 99/1, display board as claimed in any one of claims 1 to 9 Resin composition. Furthermore, the resin composition for display substrates of any one of Claims 1 thru | or 11 containing a crosslinking agent. The resin composition for display substrates according to claim 12 , wherein the crosslinking agent is a compound having two or more epoxy groups and one or more aromatic groups. The display according to claim 13 , wherein the cross-linking agent is a compound having 6 or less epoxy groups, and the compound has an alkylene group having 1 to 10 carbon atoms for bonding an epoxy group and an aromatic group. Resin composition for substrates. The resin composition for display substrates of any one of Claims 12 thru | or 14 whose said crosslinking agent is 20 mass parts or less with respect to 100 mass parts of said polyamic acids or a polyimide.

A varnish, wherein the display substrate resin composition according to any one of claims 1 to 15 is dissolved in at least one solvent. A cured film obtained using the varnish according to claim 16 . A structure comprising at least one layer comprising the cured film according to claim 17 on a substrate.   A method for producing a cured film, wherein the varnish according to claim 16 is baked at 230 degrees or more.