JP2020063443A - Resin precursor and resin composition containing the same, resin film and method for producing the same, and laminate and method for producing the same - Google Patents

Abstract

To provide a resin precursor which provides a transparent resin cured product without needing a combination with a special solvent, and provides a resin cured product that is low in residual stress generated between the resin precursor and an inorganic film, is excellent in chemical resistance, and is less in YI value by oxygen concentration in a curing step and influence on the total light transmittance.SOLUTION: A resin precursor is obtained by polymerizing a polymerization component containing an amino group and an amino group reactive group, in which the polymerization component contains a polyvalent compound having two or more groups selected from the amino group and the amino group reactive group, the polyvalent compound contains a silicon group-containing group, the polyvalent compound contains diamine represented by formula (1) and has a polysiloxane structural unit, and an amount of the silicon group-containing compound is 6-25 mass% based on the total mass of the polyvalent compound.SELECTED DRAWING: None

Description

  The present invention relates to a resin precursor and a resin composition containing the same, a resin film and a method for producing the same, and a laminate and a method for producing the same, which are used for a substrate for a flexible device, for example.

  Generally, a polyimide (PI) resin film is used as a resin film for applications requiring high heat resistance. A general polyimide resin is obtained by solution-polymerizing an aromatic dianhydride and an aromatic diamine to produce a polyimide precursor, followed by ring closure dehydration at a high temperature, thermal imidization, or chemical imidization using a catalyst. It is a high heat resistant resin produced.

  The polyimide resin is an insoluble and non-melting super heat resistant resin, and has excellent properties such as heat and oxidation resistance, heat resistance, radiation resistance, low temperature resistance, and chemical resistance. Therefore, the polyimide resin is used in a wide range of fields including electronic materials such as an insulating coating agent, an insulating film, a semiconductor, and an electrode protective film of TFT-LCD, and recently, in the field of display materials such as a liquid crystal alignment film. Instead of the glass substrate that has been used in the past, it is also being considered to be applied to a colorless transparent flexible substrate that utilizes its lightness and flexibility.

  However, a general polyimide resin is colored brown or yellow due to a high aromatic ring density, has a low transmittance in the visible light region, and is difficult to be used in a field requiring transparency.

  For the problem of improving the transparency of such a polyimide, for example, in Non-Patent Document 1, by using an acid dianhydride containing a specific structure and a diamine containing a specific structure, the transmittance and the transparency of the hue are improved. Polyimides having improved properties are described. Furthermore, in Patent Documents 1 to 4, 4,4-bis (diaminodiphenyl) sulfone (hereinafter also referred to as 4,4-DAS) and 3,3-bis (diaminodiphenyl) sulfone (hereinafter 3,3-DAS). (Also referred to as) and an acid dianhydride containing a specific structure, a polyimide having improved transmittance and hue transparency is described.

Further, in Examples 9 and 10 of Patent Document 6 below, high Tg, transparency, and high adhesion are obtained by copolymerizing a specific aromatic tetracarboxylic dianhydride with an alicyclic diamine and a silicon-containing diamine. , A polyimide precursor capable of forming a polyimide exhibiting high warpage and low warpage.
Furthermore, in Example 3 of Patent Document 7 and Example 3 of Patent Document 8 below, a polyimide precursor obtained by copolymerizing an aromatic tetracarboxylic dianhydride, bis (diaminodiphenyl) sulfone and a silicon-containing diamine is described. , The use as a semiconductor protective resin and a photosensitive resin composition.

JP 61-141732 Japanese Patent Laid-Open No. 06-171670 JP, 09-040774, A JP 2000-313804 A International Publication No. 2012/118020 Pamphlet International Publication No. 2011/122198 Pamphlet International Publication No. 1991/010699 Pamphlet JP-A-4-224823

Latest Polyimide (Basic and Application), edited by Japan Polyimide Research Association, P152

  However, the known physical properties of transparent polyimide are not sufficient for use as, for example, a semiconductor insulating film, a TFT-LCD insulating film, an electrode protective film, an ITO electrode substrate for a touch panel, and a heat-resistant colorless transparent substrate for a flexible display.

  For example, when a polyimide resin is used for a colorless transparent substrate for a flexible display, a polyimide film is formed on a support glass (hereinafter also referred to as a support), and a TFT device is usually formed on the polyimide film. , An inorganic film may be formed. When the coefficient of linear expansion of polyimide (hereinafter also referred to as CTE) is high, a residual stress is generated between the polyimide film and the inorganic film due to the CTE mismatch between the inorganic film or the support glass and the polyimide film, and as a result, the support is obtained. There are problems that the glass is warped and the performance of the TFT element is deteriorated. Therefore, there is a problem of reducing the residual stress of the polyimide in order to improve the warp of the support glass. The polyimides described in Patent Documents 1 to 4 have high residual stress, and when applied to a colorless transparent substrate for a flexible display, there is a problem that the support glass warps.

  Further, in order to form a polyimide film, for example, a glass substrate is coated with a polyimide precursor, and the glass substrate coated with the polyimide precursor is placed in an oven containing nitrogen gas at 250 ° C. It is generally necessary to heat to ˜400 ° C. (hereinafter, also referred to as a curing step). In the polyimide having improved transparency in the transmittance and the hue described in Patent Documents 1 to 4 and Non-Patent Document 1, when the oxygen concentration in the oven furnace at the time of curing is high, specifically, the oxygen concentration is 100 ppm. In the case of the above, there was a problem of oxygen concentration dependency such that the YI value increased and the total light transmittance decreased.

  Further, when a polyimide resin is used for a colorless transparent substrate for a flexible display, a TFT element is usually formed on the polyimide film by a photolithography process using a photoresist. The polyimide film used for the colorless transparent substrate for a flexible display (hereinafter, also referred to as a polyimide substrate) is used in the step of stripping the photoresist included in this step, and is exposed to a chemical such as a photoresist stripping solution, It is necessary to have chemical resistance to these agents. In the polyimide composed of 4,4-DAS or 3,3-DAS and an acid dianhydride containing a specific structure as described in Patent Document 1, a minute crack is generated in the polyimide substrate during the photoresist stripping step. There is a problem in terms of chemical resistance, such as the occurrence of a phenomenon that the polyimide substrate becomes cloudy due to the entry and the total light transmittance decreases.

  Patent Document 5 describes that a flexible silicon-containing diamine is introduced by block copolymerization for the purpose of reducing residual stress while maintaining the glass transition temperature and Young's modulus of polyimide. However, as described in Comparative Example 4 of Patent Document 5, when a silicon-containing diamine is copolymerized in a block, phase separation of a silicone moiety proceeds unless a polyimide precursor is dissolved using a special solvent combination, In the sea-island structure having different refractive indexes, the structure of the island portion becomes large, so that the film becomes cloudy and the total light transmittance decreases. Also, when using a combination of low boiling point special solvent, after coating the polyimide precursor solution to the substrate, if left for several hours at room temperature, haze may occur, the coating film may become cloudy, leaving time Had to manage. In this way, in order to prepare a transparent thermosetting film by polyimide block-copolymerized with a silicon-containing diamine, after dissolving the precursor using a combination of special solvents, after applying the precursor solution There was a problem that it was necessary to manage the neglected time.

  Further, Examples 9 and 10 of Patent Document 6 describe a polyimide precursor obtained by copolymerizing an aromatic tetracarboxylic dianhydride, an alicyclic diamine and a silicone diamine, and a polyimide obtained from the polyimide precursor. There is. However, as confirmed by the present inventors, this polyamide has a problem that the yellowness is high, the total light transmittance is low, and the yellowness and the transmittance are easily affected by the oxygen concentration during curing of the polyimide ( See Comparative Example 25 of the present specification).

  Then, Patent Documents 7 and 8 describe a polyimide precursor obtained by copolymerizing (diaminodiphenyl) sulfone, an aromatic tetracarboxylic dianhydride, and a silicone diamine, and a polyimide obtained from the polyimide precursor. However, as confirmed by the present inventors, the mass ratio of the silicon group-containing monomer to the total mass of the silicon group-containing monomer, the polyvalent carboxylic derivative, and the diamine compound used when synthesizing the polyimide precursor is as follows: , The resulting polyimide has a large residual stress and is unsuitable for the display process. On the other hand, since Patent Document 8 has many, the resulting polyimide becomes cloudy and unsuitable for use in a transparent display. There was a problem (see comparative examples 23 and 24 in the present specification).

  The present invention has been made in view of the above-described problems, can provide a transparent resin cured product without the need for a special solvent combination, and occurs between the inorganic film and An object of the present invention is to provide a resin precursor capable of giving a resin cured product having low residual stress, excellent chemical resistance, and a small effect on the YI value and the total light transmittance due to the oxygen concentration during the curing step. . Another object of the present invention is to provide a resin composition containing the resin precursor, a resin film obtained by curing the resin composition, a method for producing the resin film, and a laminate and a method for producing the laminate.

  The present inventors have conducted extensive studies to solve the above problems, the heat-resistant resin precursor having a specific structure can form a transparent resin cured product without the need for a combination of special solvents, In addition, such a resin cured product has a low residual stress generated between the resin and the inorganic film, is excellent in chemical resistance, and has a small influence on the YI value and the total light transmittance due to the oxygen concentration during the curing step. Therefore, the present invention has been completed based on this finding. That is, the present invention is as follows.

で表されるジアミンを含み、
該樹脂前駆体が、下記一般式（２）：

｛式中、複数存在するＲ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、そしてｈは、３〜２００の整数である。｝で表される構造を有し、
該ケイ素基含有化合物の量が該多価化合物の総質量基準で６質量％〜２５質量％である、
該樹脂前駆体。
［２］ 該アミノ基反応性基が、カルボキシル基、置換カルボキシル基及び酸無水物基からなる群から選択される１つ以上を含む、［１］に記載の樹脂前駆体。
［３］ 該ケイ素基含有化合物が、下記一般式（３）：

｛式中、複数存在するＲ₂は、それぞれ独立に、単結合又は炭素数１〜２０の二価の有機基であり、Ｒ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、複数存在してもよいＲ₅は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、Ｌ₁、Ｌ₂、及びＬ₃は、それぞれ独立に、アミノ基、イソシアネート基、カルボキシル基、酸無水物基、酸エステル基、酸ハライド基、ヒドロキシ基、エポキシ基、又はメルカプト基であり、ｊは、３〜２００の整数であり、ｋは、０〜１９７の整数である。｝で表されるシリコーン化合物を含む、［１］又は［２］に記載の樹脂前駆体。
［４］ 該一般式（３）において、Ｌ₁及びＬ₂が、それぞれ独立に、アミノ基又は酸無水物基であり、そしてｋが０である、［３］に記載の樹脂前駆体。
［５］ 該一般式（３）において、Ｌ₁及びＬ₂が共にアミノ基である、［４］に記載の樹脂前駆体。
［６］ 該樹脂前駆体が、ユニット１及びユニット２を含有し、
該ユニット１が、少なくとも下記一般式（４）；

｛式中、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、複数存在してもよいＸ₁は、それぞれ独立に、炭素数４〜３２の四価の有機基であり、そしてｎは、１〜１００の整数である。｝
で表される構造を有し、
該ユニット２が、下記一般式（５）：

｛式中、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、複数存在するＲ₂は、それぞれ独立に、炭素数３〜２０の二価の脂肪族炭化水素、又は二価の芳香族基であり、Ｒ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、複数存在してもよいＸ₂は、それぞれ独立に、炭素数４〜３２の四価の有機基であり、ｌは、３〜５０の整数であり、そしてｍは、１〜１００の整数である。｝で表される構造、又は、下記一般式（６）：

｛式中、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、複数存在するＲ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、複数存在するＲ₈は、それぞれ独立に、炭素数３〜２０の三価の脂肪族炭化水素、又は三価の芳香族基であり、ｐは、１〜１００の整数であり、そしてｑは３〜５０の整数である。｝で表される構造、又は上記一般式（５）で表される構造と上記一般式（６）で表される構造の両者、を有する、［１］〜［５］のいずれか１項に記載の樹脂前駆体。
［７］ 該ユニット１及び該ユニット２の合計量が、該樹脂前駆体の総質量基準で３０質量％以上である、［６］に記載の樹脂前駆体。
［８］ 該樹脂前駆体が、下記一般式（７）：

｛式中、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、複数存在してもよいＸ₃は、それぞれ独立に、炭素数４〜３２の二価の有機基であり、複数存在してもよいＸ₄は、それぞれ独立に、炭素数４〜３２の四価の有機基であり、そしてｔは１〜１００の整数である。｝で表される構造を有するユニット３を更に含有する、［６］又は［７］に記載の樹脂前駆体。
［９］ 該一般式（７）において、Ｘ₃が、２，２’−ビス（トリフルオロメチル）ベンジジンからアミノ基を除いた構造である残基である、［８］に記載の樹脂前駆体。
［１０］ 該ユニット１及び該ユニット２が、
ピロメリット酸二無水物（ＰＭＤＡ）及びビフェニルテトラカルボン酸二無水物（ＢＰＤＡ）からなる群より選ばれる１つ以上に由来する部位と、
４，４’−オキシジフタル酸二無水物（ＯＤＰＡ）、４，４’−（ヘキサフルオロイソプロピリデン）ジフタル酸無水物（６ＦＤＡ）、シクロヘキサン−１，２，４，５−テトラカルボン酸二無水物（ＣＨＤＡ）、３，３’，４，４’−ジフェニルスルホンテトラカルボン酸二無水物（ＤＳＤＡ）、４，４’−ビフェニルビス（トリメリット酸モノエステル酸無水物）（ＴＡＨＱ）、及び９，９’−ビス（３，４−ジカルボキシフェニル）フルオレン二無水物（ＢＰＡＦ）からなる群より選ばれる１つ以上に由来する部位と
の組み合わせである部位を、該ユニット１及び該ユニット２の酸二無水物由来部位の総量基準で６０モル％以上の量で含む、［６］〜［９］のいずれか１項に記載の樹脂前駆体。
［１１］ 該Ｒ₃及び該Ｒ₄が、それぞれ独立に、炭素数１〜３の一価の脂肪族炭化水素基、又は炭素数６〜１０の一価の芳香族炭化水素基である、［１］〜［１０］のいずれか１項に記載の樹脂前駆体。
［１２］ 該Ｒ₃及び該Ｒ₄の少なくとも一部がフェニル基である、［１］〜［１１］のいずれか１項に記載の樹脂前駆体。
［１３］ 該樹脂前駆体を不活性雰囲気下３００〜５００℃の条件で加熱硬化させて得られる樹脂が、−１５０℃〜０℃の領域の少なくとも１つのガラス転移温度及び１５０℃〜３８０℃の領域の少なくとも１つのガラス転移温度を有し、かつ０℃より大きく１５０℃より小さい領域においてガラス転移温度を有さない、［１］〜［１２］のいずれか１項に記載の樹脂前駆体。
［１４］ ビフェニルテトラカルボン酸二無水物（ＢＰＤＡ）由来の部位を、該樹脂前駆体の酸二無水物由来部位の総量基準で２０モル％以上含む、［１］〜［１３］のいずれか１項に記載の樹脂前駆体。
［１５］ 一部がイミド化されている、［１］〜［１４］のいずれか１項に記載の樹脂前駆体。
［１６］ ［１］〜［１５］のいずれか１項に記載の樹脂前駆体と、下記一般式（８）：

｛式中、複数存在してもよいＸ₃は、それぞれ独立に、炭素数４〜３２の四価の有機基であり、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、そしてｒは、１〜１００の整数である。｝で表される構造を有する樹脂前駆体とを含む、前駆体混合物。
［１７］ ［１］〜［１５］のいずれか１項に記載の樹脂前駆体、又は［１６］に記載の前駆体混合物を含む、フレキシブルデバイス材料。
［１８］ ［１］〜［１５］のいずれか１項に記載の樹脂前駆体の硬化物又は［１６］に記載の前駆体混合物の硬化物である、樹脂フィルム。
［１９］ ［１］〜［１５］のいずれか１項に記載の樹脂前駆体又は［１６］に記載の前駆体混合物と、溶媒と、を含有する、樹脂組成物。
［２０］ 該樹脂組成物を支持体の表面に展開した後、該樹脂組成物を窒素雰囲気下３００℃〜５００℃で加熱することによって該樹脂組成物に含まれる該樹脂前駆体をイミド化して得られる樹脂が示す２０μｍ膜厚での黄色度が７以下である、［１９］に記載の樹脂組成物。
［２１］ 該樹脂組成物を支持体の表面に展開した後、該樹脂組成物を窒素雰囲気下３００℃〜５００℃で加熱することによって該樹脂組成物に含まれる該樹脂前駆体をイミド化して得られる樹脂が示す１０μｍ膜厚での残留応力が２５ＭＰａ以下である、［１９］又は［２０］に記載の樹脂組成物。
［２２］ ［１９］〜［２１］のいずれか１項に記載の樹脂組成物の硬化物である、樹脂フィルム。
［２３］ ［１９］〜［２１］のいずれか１項に記載の樹脂組成物を支持体の表面上に展開する工程と、
該支持体及び該樹脂組成物を加熱して該樹脂組成物に含まれる該樹脂前駆体をイミド化して樹脂フィルムを形成する工程と、
該樹脂フィルムを該支持体から剥離する工程と、
を含む、樹脂フィルムの製造方法。
［２４］ 支持体と、該支持体の表面上に形成された、［１９］〜［２１］のいずれか１項に記載の樹脂組成物の硬化物である樹脂膜とを含む、積層体。
［２５］ 支持体の表面上に、［１９］〜［２１］のいずれか１項に記載の樹脂組成物を展開する工程と、
該支持体及び該樹脂組成物を加熱して該樹脂組成物に含まれる該樹脂前駆体をイミド化して樹脂膜を形成し、これにより該支持体及び該樹脂膜を含む積層体を得る工程と、
を含む、積層体の製造方法。
［２６］ ディスプレイ基板の製造に用いられるポリイミド樹脂膜であって、厚み２０μｍにおけるＲｔｈが２０〜９０ｎｍである、ポリイミド樹脂膜。
［２７］ 支持体の表面上にポリイミド前駆体を含む樹脂組成物を展開する工程と、
該支持体及び該樹脂組成物を加熱してポリイミド前駆体をイミド化して、［２６］に記載のポリイミド樹脂膜を形成する工程と、
該ポリイミド樹脂膜上に素子を形成する工程と、
該素子が形成された該ポリイミド樹脂膜を該支持体から剥離する工程と
を含む、ディスプレイ基板の製造方法。 [1] A resin precursor obtained by polymerizing a polymerization component containing an amino group and an amino group-reactive group,
The polymerization component contains a polyvalent compound having two or more groups selected from an amino group and an amino group-reactive group,
The polyvalent compound includes a silicon group-containing compound,
The polyvalent compound has the following formula (1):

Including a diamine represented by
The resin precursor has the following general formula (2):

{In the formula, a plurality of R ₃ and R _{4 present} are each independently a monovalent organic group having 1 to 20 carbon atoms, and h is an integer of 3 to 200. } Has a structure represented by
The amount of the silicon group-containing compound is 6% by mass to 25% by mass based on the total mass of the polyvalent compound,
The resin precursor.
[2] The resin precursor according to [1], wherein the amino group-reactive group contains one or more selected from the group consisting of a carboxyl group, a substituted carboxyl group and an acid anhydride group.
[3] The silicon group-containing compound has the following general formula (3):

{In the formula, a plurality of R _2's each independently represent a single bond or a divalent organic group having 1 to 20 carbon atoms, and R ₃ and R ₄ each independently represent one of 1 to 20 carbon atoms. R ₅ which is a valent organic group and may be present in plural numbers are each independently a monovalent organic group having 1 to 20 carbon atoms, and L ₁ , L ₂ and L ₃ are each independently It is an amino group, an isocyanate group, a carboxyl group, an acid anhydride group, an acid ester group, an acid halide group, a hydroxy group, an epoxy group, or a mercapto group, j is an integer of 3 to 200, and k is 0 to 0. It is an integer of 197. } The resin precursor as described in [1] or [2] containing the silicone compound represented by these.
[4] The resin precursor according to [3], wherein in the general formula (3), L ₁ and L ₂ are each independently an amino group or an acid anhydride group, and k is 0.
[5] The resin precursor according to [4], wherein in the general formula (3), L ₁ and L ₂ are both amino groups.
[6] The resin precursor contains Unit 1 and Unit 2,
The unit 1 has at least the following general formula (4);

{In the formula, R ₁ existing in plural, each independently, a hydrogen atom, an aliphatic hydrocarbon, or a monovalent aromatic group having a monovalent C1-20, optionally X ₁ be a plurality of present Are each independently a tetravalent organic group having 4 to 32 carbon atoms, and n is an integer of 1 to 100. }
Has a structure represented by
The unit 2 has the following general formula (5):

{In the formula, a plurality of R _1's are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or a monovalent aromatic group, and a plurality of R _2's are respectively Independently, it is a divalent aliphatic hydrocarbon having 3 to 20 carbon atoms or a divalent aromatic group, and R ₃ and R ₄ are each independently a monovalent organic group having 1 to 20 carbon atoms. X ₂ , which may be present, are each independently a tetravalent organic group having 4 to 32 carbon atoms, l is an integer of 3 to 50, and m is an integer of 1 to 100. Is. } Or the following general formula (6):

{In the formula, a plurality of R ₁ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or a monovalent aromatic group, and a plurality of R ₃ and R _{4 are present.} Are each independently a monovalent organic group having 1 to 20 carbon atoms, and a plurality of R ₈ are each independently an trivalent aliphatic hydrocarbon having 3 to 20 carbon atoms or a trivalent aromatic group. Is a group group, p is an integer from 1 to 100, and q is an integer from 3 to 50. } Or a structure represented by the above general formula (5) and a structure represented by the above general formula (6), any one of [1] to [5] The resin precursor described.
[7] The resin precursor according to [6], wherein the total amount of the unit 1 and the unit 2 is 30% by mass or more based on the total mass of the resin precursor.
[8] The resin precursor has the following general formula (7):

{In the formula, R ₁ existing in plural, each independently, a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or an aromatic group of monovalent, optionally X ₃ be plurality of Are each independently a divalent organic group having 4 to 32 carbon atoms, and a plurality of X ₄ which may be present are each independently a tetravalent organic group having 4 to 32 carbon atoms, and t Is an integer of 1 to 100. } The resin precursor as described in [6] or [7] which further contains the unit 3 which has a structure represented by these.
[9] The resin precursor according to [8], wherein in the general formula (7), X ₃ is a residue having a structure in which an amino group is removed from 2,2′-bis (trifluoromethyl) benzidine. .
[10] The unit 1 and the unit 2 are
A moiety derived from one or more selected from the group consisting of pyromellitic dianhydride (PMDA) and biphenyltetracarboxylic dianhydride (BPDA);
4,4'-oxydiphthalic dianhydride (ODPA), 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), cyclohexane-1,2,4,5-tetracarboxylic dianhydride ( CHDA), 3,3 ', 4,4'-diphenylsulfone tetracarboxylic acid dianhydride (DSDA), 4,4'-biphenylbis (trimellitic acid monoester acid anhydride) (TAHQ), and 9,9. A portion that is a combination with a portion derived from one or more selected from the group consisting of'-bis (3,4-dicarboxyphenyl) fluorene dianhydride (BPAF) is used as the acid diamine of the unit 1 and the unit 2. The resin precursor according to any one of [6] to [9], which is contained in an amount of 60 mol% or more based on the total amount of anhydride-derived moieties.
[11] R ₃ and R ₄ are each independently a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms, [ The resin precursor according to any one of 1] to [10].
[12] The resin precursor according to any one of [1] to [11], wherein at least part of R ₃ and R ₄ is a phenyl group.
[13] A resin obtained by heat-curing the resin precursor under an inert atmosphere at 300 to 500 ° C. has a glass transition temperature of −150 ° C. to 0 ° C. and a temperature of 150 ° C. to 380 ° C. The resin precursor according to any one of [1] to [12], which has at least one glass transition temperature in a range and does not have a glass transition temperature in a range higher than 0 ° C and lower than 150 ° C.
[14] Any one of [1] to [13], containing 20 mol% or more of sites derived from biphenyltetracarboxylic dianhydride (BPDA) based on the total amount of sites derived from the acid dianhydride of the resin precursor. The resin precursor according to item.
[15] The resin precursor according to any one of [1] to [14], which is partially imidized.
[16] The resin precursor according to any one of [1] to [15] and the following general formula (8):

{In the formula, a plurality of X ₃ which may be present are each independently a tetravalent organic group having a carbon number of 4 to 32, and a plurality of R ₁ are independently a hydrogen atom and a carbon number of 1 to 1 20 monovalent aliphatic hydrocarbons, or monovalent aromatic groups, and r is an integer from 1 to 100. } The precursor mixture containing the resin precursor which has a structure represented by these.
[17] A flexible device material containing the resin precursor according to any one of [1] to [15] or the precursor mixture according to [16].
[18] A resin film, which is a cured product of the resin precursor according to any one of [1] to [15] or a cured product of the precursor mixture according to [16].
[19] A resin composition containing the resin precursor according to any one of [1] to [15] or the precursor mixture according to [16], and a solvent.
[20] After spreading the resin composition on the surface of a support, the resin composition is heated at 300 ° C. to 500 ° C. in a nitrogen atmosphere to imidize the resin precursor contained in the resin composition. The resin composition according to [19], wherein the resin obtained has a yellowness index of 7 or less at a film thickness of 20 μm.
[21] After spreading the resin composition on the surface of a support, the resin composition contained in the resin composition is imidized by heating the resin composition at 300 ° C. to 500 ° C. in a nitrogen atmosphere. The resin composition according to [19] or [20], wherein the resin obtained has a residual stress of 25 MPa or less at a film thickness of 10 μm.
[22] A resin film, which is a cured product of the resin composition according to any one of [19] to [21].
[23] A step of developing the resin composition according to any one of [19] to [21] on the surface of a support,
Heating the support and the resin composition to imidize the resin precursor contained in the resin composition to form a resin film;
A step of peeling the resin film from the support,
A method for producing a resin film, comprising:
[24] A laminate comprising a support and a resin film formed on the surface of the support, which is a cured product of the resin composition according to any one of [19] to [21].
[25] A step of developing the resin composition according to any one of [19] to [21] on the surface of a support,
Heating the support and the resin composition to imidize the resin precursor contained in the resin composition to form a resin film, thereby obtaining a laminate including the support and the resin film. ,
A method for producing a laminate, including:
[26] A polyimide resin film used for manufacturing a display substrate, wherein Rth in a thickness of 20 μm is 20 to 90 nm.
[27] A step of developing a resin composition containing a polyimide precursor on the surface of a support,
Heating the support and the resin composition to imidize a polyimide precursor to form a polyimide resin film according to [26];
A step of forming an element on the polyimide resin film,
And a step of peeling off the polyimide resin film having the element formed thereon from the support.

  According to the present invention, a transparent resin cured product can be provided without the need for a combination of special solvents, and the residual stress generated between the transparent resin cured product and the inorganic film is low, which is excellent in chemical resistance and cured. Provided is a resin precursor capable of giving a resin cured product having a small effect on the YI value and the total light transmittance by the oxygen concentration during the process.

  Hereinafter, exemplary embodiments of the present invention (hereinafter, abbreviated as “embodiments”) will be described in detail. The present invention is not limited to the following embodiments, and can be variously modified and implemented within the scope of the gist. It should be noted that the repeating number of the structural unit in the formula of the present disclosure is only intended to be the number that the structural unit can be contained in the entire resin precursor unless otherwise specified, and accordingly, a specific bonding mode such as a block structure is used. It should be noted that is not intended. In addition, unless otherwise specified, the characteristic values described in the present disclosure are values measured by the method described in the [Example] section or a method that is understood by those skilled in the art to be equivalent thereto. Intent.

で表されるジアミンを含み、
該樹脂前駆体が、下記一般式（２）：

｛式中、複数存在するＲ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、そしてｈは、３〜２００の整数である。｝で表される構造を有し、
該ケイ素基含有化合物の量が該多価化合物の総質量基準で６質量％〜２５質量％である、
該樹脂前駆体を提供する。 <Resin precursor>
The resin precursor according to the embodiment of the present invention,
A resin precursor obtained by polymerizing a polymerization component containing an amino group and an amino group reactive group,
The polymerization component contains a polyvalent compound having two or more groups selected from an amino group and an amino group-reactive group,
The polyvalent compound includes a silicon group-containing compound,
The polyvalent compound has the following formula (1):

Including a diamine represented by
The resin precursor has the following general formula (2):

{In the formula, a plurality of R ₃ and R _{4 present} are each independently a monovalent organic group having 1 to 20 carbon atoms, and h is an integer of 3 to 200. } Has a structure represented by
The amount of the silicon group-containing compound is 6% by mass to 25% by mass based on the total mass of the polyvalent compound,
The resin precursor is provided.

The polymerization component contains an amino group and an amino group reactive group. The polymerization component contains a polyvalent compound having two or more groups selected from an amino group and an amino group-reactive group. For example, the polymerization component may be a mixture of a polyvalent compound having an amino group and a polyvalent compound having an amino group-reactive group, or a polyvalent compound containing both an amino group and an amino group-reactive group. It may be included or a combination thereof.
In the present disclosure, an amino group-reactive group means a group having reactivity with an amino group. Examples of the amino group-reactive group include an acid group (for example, a carboxyl group, an acid anhydride group, and a substituted carboxyl group (for example, an acid ester group, an acid halide group, etc.)), a hydroxy group, an epoxy group, and a mercapto group. Can be mentioned. Examples of the compound containing an acid group include dicarboxylic acids, tricarboxylic acids, tetracarboxylic acids, and acid dianhydrides, acid esterified products and acid chlorides of these carboxylic acids. Therefore, the resin precursor of the present embodiment can be a polyimide precursor. In an exemplary embodiment, the amino group-reactive group comprises one or more selected from the group consisting of a carboxyl group, a substituted carboxyl group and an acid anhydride group. In a preferred embodiment, the amino group-reactive group is one or more selected from the group consisting of a carboxyl group, a substituted carboxyl group and an acid anhydride group.

  The polyvalent compound contains at least the diamine represented by the general formula (1). Examples of the compound represented by the general formula (1) include 4,4- (diaminodiphenyl) sulfone (hereinafter, also referred to as 4,4-DAS), 3,4- (diaminodiphenyl) sulfone (hereinafter, 3,4). -DAS) and 3,3- (diaminodiphenyl) sulfone (hereinafter, also referred to as 3,3-DAS).

  At least one of the polyvalent compounds is a silicon group-containing compound. The structure represented by the general formula (2) is derived from the silicon group-containing compound. The amount of the silicon group-containing compound is 6% by mass to 25% by mass (hereinafter, this mass fraction is also referred to as the silicon group-containing monomer concentration) based on the mass of the polyvalent compound. A silicon group-containing monomer concentration of 6% by mass or more is advantageous from the viewpoint of sufficiently obtaining the effect of reducing the stress generated between the resin film and the inorganic film and the effect of decreasing the yellowness, and 7% by mass. It is preferably not less than 8% by mass, more preferably not less than 8% by mass, further preferably not less than 10% by mass. On the other hand, the concentration of the silicon group-containing monomer is 25% by mass or less, which is advantageous from the viewpoint of improving transparency, reducing yellowness, and obtaining good heat resistance without the resulting polyimide becoming cloudy. % Or less, and more preferably 20% by mass or less. From the viewpoint of improving chemical resistance, YI value, total light transmittance, birefringence index, residual stress and oxygen dependence of optical properties, the silicon group-containing monomer concentration is 10% by mass or more and 20% by mass or less. Is particularly preferable.

In the general formula (2), a plurality of R ₃ and R _{4 which} are present are each independently a monovalent organic group having 1 to 20 carbon atoms. Examples of the monovalent organic group having 1 to 20 carbon atoms include a monovalent hydrocarbon group having 1 to 20 carbon atoms, an amino group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, and an epoxy group. be able to.

  Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an aryl group having 6 to 20 carbon atoms. The alkyl group having 1 to 20 carbon atoms is preferably an alkyl group having 1 to 10 carbon atoms from the viewpoint of heat resistance and residual stress, and specifically, methyl group, ethyl group, propyl group, isopropyl group, butyl group. , Isobutyl group, t-butyl group, pentyl group, hexyl group and the like. From the above viewpoints, the cycloalkyl group having 3 to 20 carbon atoms is preferably a cycloalkyl group having 3 to 10 carbon atoms, and specific examples thereof include a cyclopentyl group and a cyclohexyl group. The aryl group having 6 to 20 carbon atoms is preferably an aryl group having 6 to 12 carbon atoms from the above viewpoint, and specific examples thereof include a phenyl group, a tolyl group and a naphthyl group.

  Examples of the amino group having 1 to 20 carbon atoms include an amino group and a substituted amino group (for example, a bis (trialkylsilyl) amino group).

  Examples of the monovalent alkoxy group having 1 to 20 carbon atoms include methoxy group, ethoxy group, propoxy group, isopropyloxy group, butoxy group, phenoxy group, propenyloxy group and cyclohexyloxy group.

In the general formula (2), a plurality of R ₃ and R ₄ each independently represent a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms. It is preferable that it is a group from the viewpoint that the resulting polyimide film has both high heat resistance and low residual stress. From this viewpoint, the monovalent aliphatic hydrocarbon having 1 to 3 carbon atoms is preferably a methyl group, and the aromatic group having 6 to 10 carbon atoms is preferably a phenyl group.

  H in the general formula (2) is an integer of 3 to 200, preferably an integer of 10 to 200, more preferably an integer of 20 to 150, further preferably an integer of 30 to 100, particularly preferably 35 to 80. Is an integer. When h is 2 or less, the residual stress of the polyimide obtained from the resin precursor of the present disclosure may be deteriorated (that is, increased), and when h exceeds 200, a varnish containing the resin precursor and the solvent may be added. When prepared, problems may occur such that the varnish becomes cloudy and the mechanical strength of the polyimide decreases.

  In the resin precursor of the present embodiment, the silicon group-containing compound has the following general formula (3):

｛式中、複数存在するＲ₂は、それぞれ独立に、単結合又は炭素数１〜２０の二価の有機基であり、Ｒ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、複数存在してもよいＲ₅は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、Ｌ₁、Ｌ₂、及びＬ₃は、それぞれ独立に、アミノ基、イソシアネート基、カルボキシル基、酸無水物基、酸エステル基、酸ハライド基、ヒドロキシ基、エポキシ基、又はメルカプト基であり、ｊは、３〜２００の整数であり、ｋは、０〜１９７の整数である。｝で表されるシリコーン化合物を含むことが好ましい。好ましい態様において、ケイ素基含有化合物は、一般式（３）で表されるシリコーン化合物である。

{In the formula, a plurality of R _2's each independently represent a single bond or a divalent organic group having 1 to 20 carbon atoms, and R ₃ and R ₄ each independently represent one of 1 to 20 carbon atoms. R ₅ which is a valent organic group and may be present in plural numbers are each independently a monovalent organic group having 1 to 20 carbon atoms, and L ₁ , L ₂ and L ₃ are each independently It is an amino group, an isocyanate group, a carboxyl group, an acid anhydride group, an acid ester group, an acid halide group, a hydroxy group, an epoxy group, or a mercapto group, j is an integer of 3 to 200, and k is 0 to 0. It is an integer of 197. } It is preferable to contain the silicone compound represented by these. In a preferred embodiment, the silicon group-containing compound is a silicone compound represented by the general formula (3).

Examples of the divalent organic group having 1 to 20 carbon atoms in R ₂ include a methylene group, an alkylene group having 2 to 20 carbon atoms, a cycloalkylene group having 3 to 20 carbon atoms, and an arylene group having 6 to 20 carbon atoms. To be The alkylene group having 2 to 20 carbon atoms is preferably an alkylene group having 2 to 10 carbon atoms from the viewpoint of heat resistance, residual stress and cost, and a dimethylene group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group. Etc. From the above viewpoints, the cycloalkylene group having 3 to 20 carbon atoms is preferably a cycloalkylene group having 3 to 10 carbon atoms, and examples thereof include a cyclobutylene group, a cyclopentylene group, a cyclohexylene group, and a cycloheptylene group. Among them, a divalent aliphatic hydrocarbon having 3 to 20 carbon atoms is preferable from the above viewpoint. The arylene group having 6 to 20 carbon atoms is preferably an aromatic group having 3 to 20 carbon atoms from the above viewpoint, and examples thereof include a phenylene group and a naphthylene group.

In general formula (3), R ₃ and R ₄ are the general formula (2) have the same meanings as R ₃ and R _4, preferred embodiments are as described above for the general formula (2). R ₅ has the same meaning as a monovalent organic group having 1 to 20 carbon atoms, that is, R ₃ and R ₄ , and a preferred embodiment is the same as R ₃ and R ₄ .

In the general formula (3), L ₁ , L ₂ , and L ₃ are each independently an amino group, an isocyanate group, a carboxyl group, an acid anhydride group, an acid ester group, an acid halide group, a hydroxy group, an epoxy group, Alternatively, it is a mercapto group.

The amino group may be substituted, and examples thereof include a bis (trialkylsilyl) amino group. Specific examples of the compound represented by the general formula (3) in which L ₁ , L ₂ and L ₃ are amino groups include amino-modified methylphenyl silicones having both ends (for example, X22-1660B- manufactured by Shin-Etsu Chemical Co., Ltd.). 3 (number average molecular weight 4,400) and X22-9409 (number average molecular weight 1,300)), both terminal amino-modified dimethyl silicone (for example, X22-161A (number average molecular weight 1,600) manufactured by Shin-Etsu Chemical Co., Ltd., X22). -161B (number average molecular weight 3,000) and KF8012 (number average molecular weight 4,400); BY16-835U (number average molecular weight 900) manufactured by Toray Dow Corning; and Cilaplane FM3311 (number average molecular weight 1000) manufactured by Chisso Corporation. ) And the like.
Specific examples of the compound in which L ₁ , L ₂ and L ₃ are isocyanate groups include the above-mentioned isocyanate-modified silicone obtained by reacting both terminal amino-modified silicone with a phosgene compound.

Specific examples of compounds in which L ₁ , L ₂ and L ₃ are carboxyl groups include, for example, Shin-Etsu Chemical Co., Ltd. X22-162C (number average molecular weight 4,600), Toray Dow Corning BY16-880 (number average). Its molecular weight is 6,600).

Specific examples of the compound in which L ₁ , L ₂ and L ₃ are acid anhydride groups include the following formula group:

で表される基の少なくとも１つを有するアシル化合物等が挙げられる。

An acyl compound having at least one of the groups represented by

Specific examples of compounds in which L ₁ , L ₂ and L ₃ are acid anhydride groups include X22-168AS (manufactured by Shin-Etsu Chemical, number average molecular weight 1,000), X22-168A (manufactured by Shin-Etsu Chemical, number average molecular weight). 2,000), X22-168B (manufactured by Shin-Etsu Chemical, number average molecular weight 3,200), X22-168-P5-8 (manufactured by Shin-Etsu Chemical, number average molecular weight 4,200), DMS-Z21 (manufactured by Gerest Co., number) The average molecular weight is 600 to 800).

Specific examples of the compound in which L ₁ , L ₂ and L ₃ are acid ester groups include reacting the above compound in which L ₁ , L ₂ and L ₃ are carboxyl groups or acid anhydride groups with alcohol. The compound etc. which are obtained are mentioned.

Specific examples of the compound in which L ₁ , L ₂ and L ₃ are acid halide groups include carboxylic acid chlorides, carboxylic acid fluorides, carboxylic acid bromides and carboxylic acid iodides.

Specific examples of compounds in which L ₁ , L ₂ and L ₃ are hydroxy groups include KF-6000 (manufactured by Shin-Etsu Chemical, number average molecular weight 900), KF-6001 (manufactured by Shin-Etsu Chemical, number average molecular weight 1,800). , KF-6002 (manufactured by Shin-Etsu Chemical, number average molecular weight 3,200), KF-6003 (manufactured by Shin-Etsu Chemical, number average molecular weight 5,000) and the like. A compound having a hydroxy group is considered to react with a compound having a carboxyl group or an acid anhydride group.

Specific examples of the compound in which L ₁ , L ₂ and L ₃ are epoxy groups are epoxy type at both ends, X22-163 (manufactured by Shin-Etsu Chemical, number average molecular weight 400), KF-105 (manufactured by Shin-Etsu Chemical, Number average molecular weight 980), X22-163A (manufactured by Shin-Etsu Chemical, number average molecular weight 2,000), X22-163B (manufactured by Shin-Etsu Chemical, number average molecular weight 3,500), X22-163C (manufactured by Shin-Etsu Chemical, number average molecular weight 5) , 400); both ends alicyclic epoxy type, X22-169AS (manufactured by Shin-Etsu Chemical, number average molecular weight 1,000), X22-169B (manufactured by Shin-Etsu Chemical, number average molecular weight 3,400); both side chain ends Epoxy type, X22-9002 (manufactured by Shin-Etsu Chemical, functional group equivalent 5,000 g / mol); and the like can be mentioned. A compound having an epoxy group is considered to react with a diamine.

Specific examples of compounds in which L ₁ , L ₂ and L ₃ are mercapto groups include X22-167B (manufactured by Shin-Etsu Chemical, number average molecular weight 3,400), X22-167C (manufactured by Shin-Etsu Chemical, number average molecular weight 4,). 600) and the like. A compound having a mercapto group is considered to react with a compound having a carboxyl group or an acid anhydride group.

From the viewpoint of improving the molecular weight of the resin precursor or from the viewpoint of the heat resistance of the resulting polyimide, L ₁ , L ₂ and L ₃ are preferably each independently an amino group or an acid anhydride group, and further resin From the viewpoint of avoiding cloudiness of the varnish containing the precursor and the solvent, or from the viewpoint of cost, it is more preferable that each independently be an amino group.
Alternatively, from the viewpoint of avoiding cloudiness of a varnish containing a resin precursor and a solvent, or from the viewpoint of cost, L ₁ and L ₂ are each independently an amino group or an acid anhydride group, and k is 0. It is preferable. In this case, it is more preferable that both L ₁ and L ₂ are amino groups.

  In the general formula (3), preferable aspects of j are the same as those described above for h in the general formula (2). In the general formula (3), k is an integer of 0 to 197, preferably 0 to 100, more preferably 0 to 50, and particularly preferably 0 to 25. When k exceeds 197, problems such as cloudiness of the varnish may occur when a varnish containing a resin precursor and a solvent is prepared. When k is 0, it is preferable from the viewpoint of improving the molecular weight of the resin precursor or the heat resistance of the resulting polyimide. When k is 0, it is advantageous that j is 3 to 200 from the viewpoint of improving the molecular weight of the resin precursor or the heat resistance of the resulting polyimide.

In a preferred embodiment, in each formula of the present disclosure, R ₃ and R ₄ are each independently a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or 6 to 6 carbon atoms from the viewpoint of residual stress and cost. 10 monovalent aromatic hydrocarbon groups. Alternatively, in each formula of the present disclosure, it is preferable that a part of R ₃ and R ₄ is a phenyl group from the viewpoint of heat resistance and residual stress.

  In a preferred embodiment, the polyvalent compound contains tetracarboxylic dianhydride and diamine. In a preferred embodiment, the polyvalent compound comprises tetracarboxylic dianhydride, dicarboxylic acid, and diamine.

<Tetracarboxylic acid dianhydride>
As the tetracarboxylic acid dianhydride as an example of the polyvalent compound contained in the polymerization raw material, specifically, an aromatic tetracarboxylic acid dianhydride having 8 to 36 carbon atoms and 6 to 36 carbon atoms. Compounds selected from the above alicyclic tetracarboxylic dianhydride are preferable from the viewpoint of reduction of YI value and total light transmittance.

  More specifically, 4,4 ′-(hexafluoroisopropylidene) diphthalic anhydride (hereinafter, also referred to as 6FDA), 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-cyclohexene -1,2 dicarboxylic acid anhydride, pyromellitic dianhydride (hereinafter, also referred to as PMDA), 1,2,3,4-benzenetetracarboxylic acid dianhydride, 3,3 ', 4,4'-benzophenone Tetracarboxylic acid dianhydride (hereinafter also referred to as BTDA), 2,2 ′, 3,3′-benzophenone tetracarboxylic acid dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic acid dianhydride ( Hereinafter, also referred to as BPDA), 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic dianhydride (hereinafter, also referred to as DSDA), 2,2 ′, 3,3′-biphenyl teto Carboxylic dianhydride, methylene-4,4'-diphthalic dianhydride, 1,1-ethylidene-4,4'-diphthalic dianhydride, 2,2-propylidene-4,4'-diphthalic dianhydride Anhydride, 1,2-ethylene-4,4'-diphthalic acid dianhydride, 1,3-trimethylene-4,4'-diphthalic acid dianhydride, 1,4-tetramethylene-4,4'-diphthalic acid Acid dianhydride, 1,5-pentamethylene-4,4'-diphthalic acid dianhydride, 4,4'-oxydiphthalic acid dianhydride (hereinafter also referred to as ODPA), thio-4,4'-diphthalic acid Dianhydride, sulfonyl-4,4'-diphthalic acid dianhydride, 1,3-bis (3,4-dicarboxyphenyl) benzene dianhydride, 1,3-bis (3,4-dicarboxyphenoxy) Benzene dianhydride, 1,4-bis (3,4-dical Xyphenoxy) benzene dianhydride, 1,3-bis [2- (3,4-dicarboxyphenyl) -2-propyl] benzene dianhydride, 1,4-bis [2- (3,4-dicarboxy) Phenyl) -2-propyl] benzene dianhydride, bis [3- (3,4-dicarboxyphenoxy) phenyl] methane dianhydride, bis [4- (3,4-dicarboxyphenoxy) phenyl] methane dianhydride 2,2-bis [3- (3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propane dianhydride ( Hereinafter, also referred to as BPADA), bis (3,4-dicarboxyphenoxy) dimethylsilane dianhydride, 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyl Disiloxane dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic acid Dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride, 1,2,7,8-phenanthrenetetracarboxylic dianhydride Substance, ethylenetetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (hereinafter also referred to as CBDA), cyclo Pentanetetracarboxylic dianhydride, cyclohexane-1,2,3,4-tetracarboxylic dianhydride, cyclohexane-1,2,4,5-tetracarboxylic dianhydride (hereinafter, C DA)), 3,3 ′, 4,4′-bicyclohexyltetracarboxylic dianhydride, carbonyl-4,4′-bis (cyclohexane-1,2-dicarboxylic acid) dianhydride, methylene-4, 4'-bis (cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,2-ethylene-4,4'-bis (cyclohexane-1,2-dicarboxylic acid) dianhydride, 1,1-ethylidene- 4,4'-bis (cyclohexane-1,2-dicarboxylic acid) dianhydride, 2,2-propylidene-4,4'-bis (cyclohexane-1,2-dicarboxylic acid) dianhydride, oxy-4, 4'-bis (cyclohexane-1,2-dicarboxylic acid) dianhydride, thio-4,4'-bis (cyclohexane-1,2-dicarboxylic acid) dianhydride, sulfonyl-4,4'-bis (cyclohexane) − , 2-Dicarboxylic acid) dianhydride, bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, rel- [1S, 5R, 6R] -3 -Oxabicyclo [3,2,1] octane-2,4-dione-6-spiro-3 '-(tetrahydrofuran-2', 5'-dione), 4- (2,5-dioxotetrahydrofuran-3- Yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride, ethylene glycol-bis- (3,4-dicarboxylic acid anhydride phenyl) ether, 4,4′-biphenylbis (tri) Mellitic acid monoester acid anhydride (hereinafter also referred to as TAHQ), 9,9′-bis (3,4-dicarboxyphenyl) fluorene dianhydride (hereinafter also referred to as BPAF). ) And the like.

  Among them, BTDA and PMDA are preferable from the viewpoint of reducing CTE, improving chemical resistance, improving glass transition temperature (Tg), and improving mechanical elongation. Further, 6FDA, ODPA, and BPADA are preferable from the viewpoint of reducing yellowness, decreasing birefringence, and improving mechanical elongation. In addition, BPDA is preferable from the viewpoint of reducing residual stress, lowering yellowness, lowering birefringence, improving chemical resistance, improving Tg, and improving mechanical elongation. Further, CHDA is preferable from the viewpoint of reducing residual stress and reducing yellowness. Among them, BPDA having a tonic structure exhibiting high chemical resistance, high Tg and low CTE, and tetracarboxylic dianhydride selected from the group consisting of 6FDA, ODPA and CHDA, which has low yellowness and birefringence. It is preferable to use and in combination from the viewpoint of high chemical resistance, reduction of residual stress, reduction of yellowness, reduction of birefringence, and improvement of total light transmittance.

  Among them, in addition to the above-mentioned effects, from the viewpoint of high elongation, improvement of chemical resistance, and high Young's modulus, the portion derived from BPDA may be 20 mol% or more of the portion derived from total acid dianhydride. It is preferably 50 mol% or more, more preferably 80 mol% or more, and even 100%.

<Dicarboxylic acid>
Further, the resin precursor in the present embodiment, in addition to the above-mentioned tetracarboxylic acid dianhydride, in a range that does not impair performance, mechanical elongation improvement, glass transition temperature improvement, yellowness reduction performance For the purpose of adjusting, the polyamide component is introduced by copolymerizing dicarboxylic acid, so that the thermosetting film can be made into polyamideimide. Examples of such a dicarboxylic acid include a dicarboxylic acid having an aromatic ring and an alicyclic dicarboxylic acid, and in particular, from the viewpoint of reducing the YI value and the total light transmittance, an aromatic dicarboxylic acid having 8 to 36 carbon atoms, And at least one compound selected from the group consisting of alicyclic dicarboxylic acids having 6 to 34 carbon atoms is preferable. Specifically, isophthalic acid, terephthalic acid, 4,4'-biphenyldicarboxylic acid, 3,4'-biphenyldicarboxylic acid, 3,3'-biphenyldicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 2,3- Naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-sulfonylbisbenzoic acid, 3,4′-sulfonylbisbenzoic acid, 3,3′-sulfonylbisbenzoic acid, 4,4'-oxybisbenzoic acid, 3,4'-oxybisbenzoic acid, 3,3'-oxybisbenzoic acid, 2,2-bis (4-carboxyphenyl) propane, 2,2-bis (3-carboxyphenyl) ) Propane, 2,2'-dimethyl-4,4'-biphenyldicarboxylic acid, 3,3'-dimethyl-4,4'-biphenyldicarboxylic acid, 2,2'-dimethyl 3,3'-biphenyldicarboxylic acid, 9,9-bis (4- (4-carboxyphenoxy) phenyl) fluorene, 9,9-bis (4- (3-carboxyphenoxy) phenyl) fluorene, 4,4'- Bis (4-carboxyphenoxy) biphenyl, 4,4'-bis (3-carboxyphenoxy) biphenyl, 3,4'-bis (4-carboxyphenoxy) biphenyl, 3,4'-bis (3-carboxyphenoxy) biphenyl , 3,3'-bis (4-carboxyphenoxy) biphenyl, 3,3'-bis (3-carboxyphenoxy) biphenyl, 4,4'-bis (4-carboxyphenoxy) -p-terphenyl, 4,4 '-Bis (4-carboxyphenoxy) -m-terphenyl, 3,4'-bis (4-carboxyphenoxy) -p-terphenyl 3,3′-bis (4-carboxyphenoxy) -p-terphenyl, 3,4′-bis (4-carboxyphenoxy) -m-terphenyl, 3,3′-bis (4-carboxyphenoxy) -m -Terphenyl, 4,4'-bis (3-carboxyphenoxy) -p-terphenyl, 4,4'-bis (3-carboxyphenoxy) -m-terphenyl, 3,4'-bis (3-carboxy Phenoxy) -p-terphenyl, 3,3'-bis (3-carboxyphenoxy) -p-terphenyl, 3,4'-bis (3-carboxyphenoxy) -m-terphenyl, 3,3'-bis (3-Carboxyphenoxy) -m-terphenyl, 1,1-cyclobutanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, 4,4′-ben Phenol Nji carboxylic acid, 1,3-phenylene diacetic acid, 1,4-phenylene diacetic acid, and include 5-aminoisophthalic acid derivatives such as described in WO 2005/068535 pamphlet. When these dicarboxylic acids are actually copolymerized with the polymer, they may be used in the form of an acid chloride derivative derived from thionyl chloride or the like or an active ester derivative.

  Among these, terephthalic acid is particularly preferable from the viewpoint of reducing the YI value and improving Tg. When the dicarboxylic acid is used instead of the tetracarboxylic acid, it is preferable that the dicarboxylic acid is 50 mol% or less based on the total number of moles of the dicarboxylic acid and the tetracarboxylic acid, from the viewpoint of chemical resistance. preferable.

<Diamine>
The diamine contained in the polymerization component contains the diamine represented by the general formula (1). The diamine represented by the general formula (1) can constitute, for example, a diamine-derived site of the unit 1 described later. In the resin precursor, the site derived from the diamine represented by the general formula (1) has suitable yellowness of the polyimide film, low birefringence, improvement of total light transmittance, and residual stress generated between the polyimide film and the inorganic film. From the viewpoint of obtaining reduction, high Tg and high breaking strength, it is preferably 20 mol% or more, more preferably 50 mol% or more, and further preferably 80 mol% or more of the total diamine-derived sites.

  Further, the diamine may include a diamine having a divalent silicon-containing group having 2 to 100 silicon atoms (hereinafter, also simply referred to as silicon-containing diamine). Examples of the silicon-containing diamine include the following general formula (9):

｛式中、複数存在するＲ₂は、それぞれ独立に、炭素数３〜２０の二価の脂肪族炭化水素、又は二価の芳香族基であり、Ｒ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、ｌは、３〜５０の整数である。｝で表されるジアミノ（ポリ）シロキサンが好適である。このようなジアミンは例えば後述のユニット２を構成できる。

{In the formula, a plurality of R _{2 s} are each independently a divalent aliphatic hydrocarbon having 3 to 20 carbon atoms or a divalent aromatic group, and R ₃ and R ₄ are each independently It is a monovalent organic group having 1 to 20 carbon atoms, and l is an integer of 3 to 50. } The diamino (poly) siloxane represented by these is preferable. Such a diamine can form, for example, the unit 2 described later.

Examples of a preferable structure of R _{2 in} the general formula (9) include a methylene group, an ethylene group, a propylene group, a butylene group and a phenylene group. Preferable examples of R ₃ and R ₄ in the general formula (9) include a methyl group, an ethyl group, a propyl group, a butyl group, a phenyl group and the like. Particularly preferred is a group.

  Specific examples of the compound represented by the above general formula (9) include amine-modified methylphenyl silicone oil modified with amine at both ends (manufactured by Shin-Etsu Chemical: X22-1660B-3 (number average molecular weight 4400), X22-9409 (number). Average molecular weight 1300)), amino-modified dimethyl silicone at both ends (manufactured by Shin-Etsu Chemical: X22-161A (number average molecular weight 1600), X22-161B (number average molecular weight 3000), KF8021 (number average molecular weight 4400), manufactured by Toray Dow Corning. : BY16-835U (number average molecular weight 900) manufactured by Chisso Corporation: Silaplane FM3311 (number average molecular weight 1000)) and the like. Of these, a methylphenyl silicone oil modified with amines at both ends is particularly preferable from the viewpoint of improving chemical resistance and Tg.

  In addition, diamine is 2,2'-bis (trifluoromethyl) benzidine (hereinafter, also referred to as TFMB), 4,4'- (or 3,4'-, 3,3'-, 2,4'-. ) Diaminodiphenyl ether, 4,4 '-(or 3,3'-) diaminodiphenyl sulfone, 4,4 '-(or 3,3'-) diaminodiphenyl sulfide, 4,4'-benzophenonediamine, 3,3 ' -Benzophenone diamine, 4,4'-di (4-aminophenoxy) phenyl sulfone, 4,4'-di (3-aminophenoxy) phenyl sulfone, 4,4'-bis (4-aminophenoxy) biphenyl, 1, 4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 2,2-bis {4- (4-aminophenoxy) phenyl} p Bread, 3,3 ', 5,5'-tetramethyl-4,4'-diaminodiphenylmethane, 2,2'-bis (4-aminophenyl) propane, 2,2', 6,6'-tetramethyl- 4,4'-diaminobiphenyl, 2,2 ', 6,6'-tetratrifluoromethyl-4,4'-diaminobiphenyl, bis {(4-aminophenyl) -2-propyl} 1,4-benzene, 9,9-bis (4-aminophenyl) fluorene, 9,9-bis (4-aminophenoxyphenyl) fluorene, 3,3'-dimethylbenzidine, 3,3'-dimethoxybenzidine and 3,5-diamino Benzoic acid, etc., 2,6-diaminopyridine, 2,4-diaminopyridine, bis (4-aminophenyl-2-propyl) -1,4-benzene, 3,3′-bis (trifluoromethyl) -4,4'-diaminobiphenyl (3,3'-TFDB), 2,2'-bis [3 (3-aminophenoxy) phenyl] hexafluoropropane (3-BDAF), 2,2'-bis [4 (4-Aminophenoxy) phenyl] hexafluoropropane (4-BDAF), 2,2'-bis (3-aminophenyl) hexafluoropropane (3,3'-6F), and 2,2'-bis ( One or more kinds selected from the group consisting of 4-aminophenyl) hexafluoropropane (4,4′-6F) may be contained. These diamines can form the diamine-derived site of the unit 3 described later. Among these, 1,4-cyclohexanediamine and TFMB are most preferable from the viewpoint of reducing yellowness, CTE, and YI value.

｛式中、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、複数存在してもよいＸ₁は、それぞれ独立に、炭素数４〜３２の四価の有機基であり、そしてｎは、１〜１００の整数である。｝
で表される構造を有し、
該ユニット２は、下記一般式（５）：

｛式中、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、複数存在するＲ₂は、それぞれ独立に、炭素数３〜２０の二価の脂肪族炭化水素、又は二価の芳香族基であり、Ｒ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、複数存在してもよいＸ₂は、それぞれ独立に、炭素数４〜３２の四価の有機基であり、ｌは、３〜５０の整数であり、そしてｍは、１〜１００の整数である。｝で表される構造、又は、下記一般式（６）：

｛式中、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、複数存在するＲ₃及びＲ₄は、それぞれ独立に、炭素数１〜２０の一価の有機基であり、複数存在するＲ₈は、それぞれ独立に、炭素数３〜２０の三価の脂肪族炭化水素、又は三価の芳香族基であり、ｐは、１〜１００の整数であり、そしてｑは３〜５０の整数である。｝で表される構造、又は上記一般式（５）で表される構造と上記一般式（６）で表される構造の両者、を有する。 The resin precursor more preferably includes the following unit 1 and unit 2.
Unit 1 has at least the following general formula (4);

{In the formula, R ₁ existing in plural, each independently, a hydrogen atom, an aliphatic hydrocarbon, or a monovalent aromatic group having a monovalent C1-20, optionally X ₁ be a plurality of present Are each independently a tetravalent organic group having 4 to 32 carbon atoms, and n is an integer of 1 to 100. }
Has a structure represented by
The unit 2 has the following general formula (5):

{In the formula, a plurality of R _1's are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or a monovalent aromatic group, and a plurality of R _2's are respectively Independently, it is a divalent aliphatic hydrocarbon having 3 to 20 carbon atoms or a divalent aromatic group, and R ₃ and R ₄ are each independently a monovalent organic group having 1 to 20 carbon atoms. X ₂ , which may be present, are each independently a tetravalent organic group having 4 to 32 carbon atoms, l is an integer of 3 to 50, and m is an integer of 1 to 100. Is. } Or the following general formula (6):

{In the formula, a plurality of R ₁ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or a monovalent aromatic group, and a plurality of R ₃ and R _{4 are present.} Are each independently a monovalent organic group having 1 to 20 carbon atoms, and a plurality of R ₈ are each independently an trivalent aliphatic hydrocarbon having 3 to 20 carbon atoms or a trivalent aromatic group. Is a group group, p is an integer from 1 to 100, and q is an integer from 3 to 50. } Or a structure represented by the above general formula (5) and a structure represented by the above general formula (6).

In the general formulas (4) and (6), the diamine-derived moiety is, for example, a group consisting of 4,4- (diaminodiphenyl) sulfone, 3,4- (diaminodiphenyl) sulfone, and 3,3- (diaminodiphenyl) sulfone. Can be derived from one or more diamines selected from In the general formulas (4) and (5), the acid anhydride-derived moiety has an acid dianhydride having a tetravalent organic group X ₁ (X ₁ is as defined above) and a tetravalent organic group X, respectively. An acid dianhydride having ₂ (X ₂ is as defined above). The diamine-derived site in the structure represented by the general formula (5) is derived from the diamino (poly) siloxane represented by the general formula (9).

The unit 1 and the unit 2 are, in terms of heat resistance, reduction of YI value and total light transmittance,
A moiety derived from one or more selected from the group consisting of pyromellitic dianhydride (PMDA) and biphenyltetracarboxylic dianhydride (BPDA);
4,4'-oxydiphthalic dianhydride (ODPA), 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), cyclohexane-1,2,4,5-tetracarboxylic dianhydride ( CHDA), 3,3 ', 4,4'-diphenylsulfone tetracarboxylic acid dianhydride (DSDA), 4,4'-biphenylbis (trimellitic acid monoester acid anhydride) (TAHQ), and 9,9. '-Bis (3,4-dicarboxyphenyl) fluorene dianhydride (BPAF) is a combination of moieties with one or more moieties selected from the group consisting of the unit 1 and unit 2 acid dianhydride. It is preferably contained in an amount of 60 mol% or more, more preferably 65 mol% or more, still more preferably 70 mol% or more, based on the total amount of the site of origin.

  In the resin precursor according to the present embodiment, the total mass of the unit 1 and the unit 2 is 30% by mass or more based on the total mass of the resin precursor, which means that the YI value and the birefringence are reduced. , From the viewpoint of improving Tg, and more preferably 70% by mass or more from the viewpoint of reducing the birefringence. Most preferably, it is 100% by mass.

｛式中、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素、又は一価の芳香族基であり、複数存在してもよいＸ₃は、それぞれ独立に、炭素数４〜３２の二価の有機基であり、複数存在してもよいＸ₄は、それぞれ独立に、炭素数４〜３２の四価の有機基であり、そしてｔは１〜１００の整数である。｝で表される構造を有するユニット３を更に含有してもよい。 Further, the resin precursor according to the present embodiment, if necessary, within the following general formula (7):

{In the formula, R ₁ existing in plural, each independently, a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or an aromatic group of monovalent, optionally X ₃ be plurality of Are each independently a divalent organic group having 4 to 32 carbon atoms, and a plurality of X ₄ which may be present are each independently a tetravalent organic group having 4 to 32 carbon atoms, and t Is an integer of 1 to 100. } You may further contain the unit 3 which has a structure represented by these.

  Unit 3 has a structure in which the diamine-derived moiety is a moiety derived from a diamine other than a compound selected from the group consisting of 4,4-DAS, 3,4-DAS, 3,3-DAS, and a silicon-containing diamine. Is.

In unit 3, R ₁ is preferably a hydrogen atom. Further, X ₃ is preferably a divalent aromatic group or an alicyclic group from the viewpoint of heat resistance, reduction of YI value and total light transmittance. Further, X ₄ is preferably a divalent aromatic group or an alicyclic group from the viewpoint of heat resistance, reduction of YI value and total light transmittance. Among them, X ₃ is preferably a residue having a structure in which an amino group is removed from 2,2′-bis (trifluoromethyl) benzidine. The organic groups X ₁ , X ₂ and X ₄ may be the same or different from each other.

  The mass ratio of the unit 3 in the resin precursor according to the present embodiment is 80% by mass or less, preferably 70% by mass or less in the total resin structure, which means that the oxygen dependence of the YI value and the total light transmittance is It is preferable from the viewpoint of reduction.

  The resin precursor according to the present embodiment is a resin obtained by heating and curing the resin precursor at 300 to 500 ° C. under an inert atmosphere (for example, an atmosphere of nitrogen or argon), or an inert resin precursor. The resin obtained by heat curing at 350 ° C. in an atmosphere has at least one glass transition temperature in the range of −150 ° C. to 0 ° C. and at least one glass transition temperature in the range of 150 ° C. to 380 ° C., and It is preferable not to have a glass transition temperature in the range of higher than 0 ° C and lower than 150 ° C. The presence of the glass transition temperature in the region of −150 ° C. to 0 ° C. and the region of 150 ° C. to 380 ° C. is preferable from the viewpoint of achieving a good balance between residual stress and total light transmittance. From the viewpoint of heat resistance, the glass transition temperature in the range of 150 ° C to 380 ° C is more preferably in the range of 200 to 380 ° C, and even more preferably in the range of 250 to 380 ° C. It is advantageous in forming such a resin precursor that the resin precursor has a block 1 and a block 2 described later.

  From the viewpoint of improving heat resistance, it is preferable that the resin precursor according to the present embodiment is composed of the block 1 mainly including the unit 1 and the block 2 mainly including the unit 2. Furthermore, the resin precursor may include the above-mentioned unit 3 in the block 1. These blocks may be connected alternately or in a permutation in the polymer chain.

  The block 1 described above contributes to the expression of Tg in the range of 150 to 380 ° C. in the polyimide obtained by heating and curing the resin precursor of the present embodiment. Therefore, the block 1 is preferably a block consisting only of repeating the above-mentioned unit 1, but it does not exclude the inclusion of the unit 3 other than the unit 1 in the range where the target Tg can be expressed.

  Similarly, the block 2 described above contributes to the expression of Tg in the range of -150 to 0 ° C in the polyimide obtained by heating and curing the resin precursor of the present embodiment. Therefore, the block 2 is preferably a block consisting only of repeating the above-mentioned unit 2, but it does not exclude the inclusion of units other than the unit 2 as long as the desired Tg can be expressed.

  In the resin precursor having the block 1 and the block 2, the sum of the repeating numbers of the unit 1 and the unit 3 in the block 1 is preferably 2 to 500, more preferably 5 to 300, and most preferably 10 to 200 on average. The number of repeating units 2 in block 2 is preferably 1.1 to 300, more preferably 1.1 to 200, and most preferably 1.2 to 100 on average per molecule. When the sum of the repeating numbers of the units 1 and 3 in the block 1 is 500 or less and the repeating number of the units 2 in the block 2 is 300 or less, the solubility of the resin precursor in a solvent is favorable, which is preferable.

  The ratio (hereinafter also referred to as unit ratio) defined by the sum of the number of repetitions of the unit 1 and the unit 3 in the block 1 divided by the number of repetitions of the unit 2 in the block 2 depends on the kind and molecular weight of the raw material used. However, it is preferably 0.5 to 100, more preferably 10 to 50. As described above, the polyimide, which is a cured product of the resin precursor having the block 1 and the block 2, has the glass transition temperature derived from the block 1 in the region A of 150 ° C. to 380 ° C. and the glass derived from the block 2. It can have the advantage that it has a transition temperature in the region B of −150 ° C. to 0 ° C. and that the region C between the region A and the region B has no glass transition temperature. When the value of the above unit ratio is 0.5 or more, the heat resistance of the cured polyimide resin is sufficient, which is preferable. When it is 100 or less, the residual stress can be lowered, which is preferable.

  On the other hand, when a high molecular weight silicone compound (specifically, a silicone compound having an average molecular weight of 3000 or more) is used as the silicon group-containing compound in the polymerization component, it can be obtained without forming a block copolymer as described above. The polyimide may exhibit a low residual stress with the inorganic film while maintaining a high glass transition temperature. This is because, according to the high molecular weight silicone compound, the silicone unit itself has a long-chain siloxane structure, and it is considered that the silicone unit has the same function as the block structure. Here, when the silicone compound has a high molecular weight, the functional group concentration decreases, so that the above-mentioned high glass transition temperature and low residual stress can be exhibited even if the number of moles charged is small.

  For example, when the high molecular weight silicone compound is a diamine, the resin precursor is a mixture of the unit 1 of general formula (4) derived from (diaminodiphenyl) sulfone and the unit 2 of general formula (5) derived from silicone diamine. In addition to the polymer, a polyimide precursor mixture, or blend, is formed in which there is a single (ie, unit 2 not copolymerized) Unit 1 polyimide precursor.

  Therefore, the present disclosure also includes a precursor mixture containing the resin precursor of the present embodiment described above and an additional resin precursor (for example, the polyimide precursor of the unit 1 alone). Here, as a specific example of the polyimide precursor of the unit 1 alone, the following general formula (8):

｛式中、複数存在してもよいＸ₃は、それぞれ独立に、炭素数４〜３２の四価の有機基であり、複数存在するＲ₁は、それぞれ独立に、水素原子、炭素数１〜２０の一価の脂肪族炭化水素基、又は一価の芳香族基であり、そしてｒは、１〜１００の整数である。｝で表される構造を有する樹脂前駆体が挙げられる。

{In the formula, a plurality of X ₃ which may be present are each independently a tetravalent organic group having a carbon number of 4 to 32, and a plurality of R ₁ are independently a hydrogen atom and a carbon number of 1 to 1 20 monovalent aliphatic hydrocarbon groups, or monovalent aromatic groups, and r is an integer of 1-100. } The resin precursor which has a structure represented by these is mentioned.

On the other hand, in the case where the high molecular weight silicone compound is other than diamine, for example, in the general formula (3), L ₁ , L ₂ and L ₃ are each independently an acid anhydride group, a carboxyl group or an acid ester group. , An acid halide group, a hydroxy group, an epoxy group, or a mercapto group.

  When the polymer component in the resin precursor according to the present embodiment contains a high molecular weight silicone compound, the polyimide, which is a cured product of the resin precursor, maintains a high glass transition temperature in the range of 150 ° C to 380 ° C. It is possible to achieve the unique property that the residual stress with the inorganic film can be significantly reduced.

  The number average molecular weight of the resin precursor according to this embodiment is preferably 3,000 to 1,000,000, more preferably 5,000 to 50,000, further preferably 7,000 to 300,000, and particularly preferably 10,000 to 250,000. The molecular weight of 3,000 or more is preferable from the viewpoint of obtaining good heat resistance and strength (for example, strength and elongation), and the molecular weight of 1,000,000 or less is preferable from the viewpoint of obtaining good solubility in a solvent, coating, etc. It is preferable from the viewpoint that coating can be performed at a desired film thickness during processing without blurring. From the viewpoint of obtaining a high mechanical elongation, the molecular weight is preferably 50,000 or more. In the present disclosure, the number average molecular weight is a value calculated in terms of standard polystyrene using gel permeation chromatography.

  In a preferred embodiment, the resin precursor may be partially imidized.

  The resin precursor of the present embodiment has a glass transition temperature of 150 ° C. to 380 ° C. on the high temperature side as heat resistance that can withstand a display manufacturing process including a TFT element device on a colorless transparent polyimide substrate, and is inorganic. It is possible to form a polyimide resin in which the residual stress between the film and the film is 25 MPa or less at a film thickness of 10 μm. Further, in a more preferred embodiment, the resin precursor can form a polyimide resin having a glass transition temperature of 240 ° C. to 380 ° C. and a residual stress with the inorganic film of 20 MPa or less at a film thickness of 10 μm. In the polyimide resin, when the glass transition temperature exists at −150 to 0 ° C., this temperature is not higher than room temperature and therefore does not affect the heat resistance required in the actual display manufacturing process.

In a preferred embodiment, the resin precursor has the following characteristics.
A solution obtained by dissolving the resin precursor in a solvent (for example, N-methyl-2-pyrrolidone) is spread on the surface of the support, and then the solution is heated at 300 to 500 ° C (for example, 350 ° C) under a nitrogen atmosphere. The resin obtained by imidizing the resin precursor by (for example, 1 hour) has a yellowness of 7 or less at a film thickness of 20 μm.
A solution obtained by dissolving the resin precursor in a solvent (for example, N-methyl-2-pyrrolidone) is spread on the surface of the support, and then the solution is heated at 300 to 500 ° C (for example, 350 ° C) under a nitrogen atmosphere. The resin obtained by imidizing the resin precursor by (for example, 1 hour) has a residual stress of 25 MPa or less at a film thickness of 10 μm.

<Production of resin precursor>
Next, a method for synthesizing the resin precursor according to this embodiment will be described. For example, when the resin precursor according to the present embodiment is composed of two blocks such as the block 1 and the block 2 described above, the polyimide precursor corresponding to each block is separately prepared, and then, The resin precursor according to the present embodiment can be obtained by mixing both and subjecting them to a condensation reaction. Here, in order to allow both blocks to be subjected to a condensation reaction, when the terminal group of the polyimide precursor of one block is carboxylic acid, the terminal group of the polyimide precursor of the other block becomes an amino group. For example, the molar ratio of the raw materials, for example, the molar ratio of tetracarboxylic dianhydride and diamine is adjusted. With this method, a polyimide precursor having a more preferable complete block property can be synthesized.

  On the other hand, the polymerization raw material tetracarboxylic dianhydride is common between block 1 and block 2, aromatic diamine is used as the raw material of block 1, and silicon-containing diamine having high reactivity is used as the raw material of block 2. When used, it may be possible to use a synthetic method utilizing the difference in reactivity between the two diamines. For example, a polyimide precursor having a certain degree of blocking property can be produced by simultaneously adding an aromatic diamine and a silicon-containing diamine to a previously prepared tetracarboxylic dianhydride and subjecting it to a condensation reaction. This method cannot synthesize a blocky polyimide precursor having a perfect blocking property, but can synthesize a blocky polyimide precursor. Here, having a block property means that a glass transition temperature corresponding to each block is observed in the polyimide resin after heat curing, for example, the polyimide resin is 4, 4 in each of the above-mentioned regions A and B. Block 1 derived from a polycondensate of one or more selected from the group consisting of-(diaminodiphenyl) sulfone, 3,4- (diaminodiphenyl) sulfone and 3,3- (diaminodiphenyl) sulfone and a tetracarboxylic acid anhydride. And the glass transition temperature of the block 2 derived from the polycondensation product of the silicon-containing diamine and the tetracarboxylic acid anhydride.

  As described above, in the resin precursor according to the present embodiment, the polyimide resin obtained by heating and curing the resin precursor has glass transition temperatures in the high temperature side region A and the low temperature side region B, respectively. It is advantageous to have a certain degree of blocking property, but this advantage can be obtained even if the polyimide resin does not have complete blocking property. Further, the above-mentioned advantage of the resin precursor having the blocks 1 and 2 is that the units other than the blocks 1 and 2 are contained unless the glass transition temperature is observed in the region C between the region A and the region B. You can get it even if you do.

  In addition, by adding N, N-dimethylformamide dimethyl acetal or N, N-dimethylformamide diethyl acetal to the polyamic acid as described above and heating, a part of or all of the carboxylic acid is esterified, It is also possible to improve the viscosity stability of a solution containing a resin precursor and a solvent during storage at room temperature. In addition to these ester-modified polyamic acids, the above-mentioned tetracarboxylic acid anhydride is reacted with a dehydration condensing agent such as thionyl chloride or dicyclohexylcarbodiimide after previously reacting with 1 equivalent of a monohydric alcohol with respect to the acid anhydride group. It can also be obtained by conducting a condensation reaction with a diamine after the reaction.

<Resin composition>
Another aspect of the present invention provides a resin composition containing the above-mentioned resin precursor or precursor mixture and a solvent. The resin composition is typically a varnish.

  In a more preferred embodiment, the resin composition is a carboxylic acid component and a diamine component, which are dissolved in a solvent, for example, an organic solvent and reacted to give a polyamic acid solution containing a polyamic acid and a solvent, which is one embodiment of the resin precursor. It can be manufactured. Here, the conditions during the reaction are not particularly limited, but for example, the reaction temperature is −20 to 150 ° C., and the reaction time is 2 to 48 hours. In order to sufficiently proceed the reaction of the silicon group-containing compound, heating at 120 ° C. for about 30 minutes is preferable. Further, during the reaction, an inert atmosphere such as argon or nitrogen is preferable.

  The solvent is not particularly limited as long as it is a solvent that dissolves polyamic acid. Known reaction solvents include dimethylene glycol dimethyl ether (DMDG), m-cresol, N-methyl-2-pyrrolidone (NMP), dimethylformamide (DMF), dimethylacetamide (DMAc), dimethylsulfoxide (DMSO), acetone, diethyl. One or more polar solvents selected from acetate, Examide M100 (trade name: manufactured by Idemitsu Kosan) and Examide B100 (trade name: manufactured by Idemitsu Kosan) are useful. Of these, NMP, DMAc, examide M100 and examide B100 are preferable. In addition, a low boiling point solution such as tetrahydrofuran (THF) or chloroform, or a low absorption solvent such as γ-butyrolactone may be used.

  In addition, in the resin composition of the present invention, an alkoxysilane compound is added to 100% by mass of the resin precursor in order that the resulting polyimide may provide sufficient adhesion to a support when forming an element such as a TFT. Is preferably 0.01 to 2% by mass.

  When the content of the alkoxysilane compound is 0.01% by mass or more with respect to 100% by mass of the resin precursor, good adhesion to the support can be obtained, and the content of the alkoxysilane compound is It is preferably 2% by mass or less from the viewpoint of storage stability of the resin composition. The content of the alkoxysilane compound is more preferably 0.02 to 2% by mass, further preferably 0.05 to 1% by mass, and 0.05 to 0.5% based on the resin precursor. The content is more preferably mass%, and particularly preferably 0.1 to 0.5 mass%.

  Examples of the alkoxysilane compound include 3-ureidopropyltriethoxysilane, bis (2-hydroxyethyl) -3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, phenyltrimethoxysilane and γ-aminopropyltriethoxysilane. Ethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltripropoxysilane, γ-aminopropyltributoxysilane, γ-aminoethyltriethoxysilane, γ-aminoethyltrimethoxysilane, γ-aminoethyltripropoxysilane , Γ-aminoethyltributoxysilane, γ-aminobutyltriethoxysilane, γ-aminobutyltrimethoxysilane, γ-aminobutyltripropoxysilane, γ-aminobutyltributoxysilane, and the like. These may be used in combination of two or more.

  After producing the above-mentioned varnish, the solution may be heated at 130 to 200 ° C. for 5 minutes to 2 hours to partially dehydrate imidize the polymer to such an extent that precipitation of the polymer does not occur. The imidation ratio can be controlled by controlling the temperature and the time. By performing partial imidization, the viscosity stability of the resin precursor solution during storage at room temperature can be improved. The imidization ratio is preferably 5% to 70% from the viewpoint of the solubility of the resin precursor in the solution and the storage stability of the solution.

In a preferred embodiment, the resin composition has the following characteristics.
Included in the resin composition by spreading the resin composition on the surface of the support and then heating the resin composition at 300 ° C. to 500 ° C. under a nitrogen atmosphere (or by heating at 350 ° C. under a nitrogen atmosphere). The resin obtained by imidizing a resin precursor has a yellowness of 7 or less at a film thickness of 20 μm.
Included in the resin composition by spreading the resin composition on the surface of the support and then heating the resin composition at 300 ° C. to 500 ° C. under a nitrogen atmosphere (or by heating at 350 ° C. under a nitrogen atmosphere). The residual stress at a film thickness of 10 μm exhibited by the resin obtained by imidizing a resin precursor is 25 MPa or less.

<Resin film>
Another aspect of the present invention provides a resin film which is a cured product of the above resin precursor, a cured product of the above precursor mixture, or a cured product of the above resin composition.
Another aspect of the present invention is a step of developing the above-mentioned resin composition on the surface of a support,
Heating the support and the resin composition to imidize a resin precursor contained in the resin composition to form a resin film;
A step of peeling the resin film from the support,
There is provided a method for producing a resin film, comprising:

  In a preferred embodiment of the method for producing a resin film, a polyamic acid solution obtained by dissolving an acid dianhydride component and a diamine component in an organic solvent and reacting them can be used as the resin composition.

  Here, the support is, for example, an inorganic substrate such as a glass substrate such as a non-alkali glass substrate, but is not particularly limited.

  More specifically, the resin composition described above is spread and dried on the adhesive layer formed on the main surface of the inorganic substrate, and cured at a temperature of 300 to 500 ° C. under an inert atmosphere to obtain a resin. A film can be formed. Finally, the resin film is peeled off from the support.

  Here, examples of the spreading method include known coating methods such as spin coating, slit coating, and blade coating. In addition, the heat treatment is performed by developing the polyamic acid solution on the adhesive layer, then heat-treating at a temperature of 300 ° C. or lower for 1 to 300 minutes mainly for the purpose of desolvation, and further from 300 ° C. to 550 in an inert atmosphere such as nitrogen. The resin precursor is heat-treated at a temperature of [deg.] C. for 1 minute to 300 minutes to form a polyimide. When producing a conventional colorless and transparent polyimide film, it is necessary to control the oxygen concentration in the oven to 100 ppm or less from the viewpoint of reducing the YI value and the total light transmittance. According to the body, a control of 500 ppm or less is sufficient. From the viewpoint of reducing the YI value and improving the total light transmittance, the oxygen concentration is preferably 1000 ppm or less.

  The thickness of the resin film according to the present embodiment is not particularly limited, but is preferably in the range of 10 to 200 μm, more preferably 10 to 50 μm.

  The resin film according to the present embodiment preferably has a yellowness of 7 or less at a film thickness of 20 μm. Further, it is preferable that the residual stress is 25 MPa or less at a film thickness of 10 μm. In particular, it is more preferable that the yellowness at a film thickness of 20 μm is 7 or less, and the residual stress at a film thickness of 10 μm is 25 MPa or less. Such characteristics are favorably realized, for example, by imidizing the resin precursor of the present disclosure in a nitrogen atmosphere at 300 ° C to 500 ° C, more specifically 350 ° C.

<Laminate>
Another aspect of the present invention provides a laminate including a support and a resin film formed on the surface of the support, which is a cured product of the resin composition described above.
Another aspect of the present invention is a step of developing the above resin composition on the surface of a support,
Heating the support and the resin composition to imidize the resin precursor contained in the resin composition to form a resin film, thereby obtaining a laminate including the support and the resin film. ,
There is provided a method for producing a laminate, including:
Such a laminated body can be manufactured by, for example, not peeling the resin film formed in the same manner as the above-described resin film manufacturing method from the support.

This laminated body is used, for example, in manufacturing a flexible device. More specifically, a semiconductor device is formed on a polyimide film, and then the support is peeled off to obtain a flexible device including a flexible transparent substrate made of a polyimide film.
Therefore, another aspect of the present invention provides a flexible device material comprising the resin precursor or the precursor mixture described above.

  As described above, the resin precursor according to the present embodiment has a specific structure, so that a resin film that does not become cloudy can be formed without requiring a special combination of solvents. Further, the yellowness (YI value) and the total light transmittance of the obtained resin film hardly depend on the oxygen concentration during curing. In addition, the residual stress generated between the resin film and the inorganic film is low, it has a practical glass transition temperature that can withstand the TFT manufacturing process, it has excellent mechanical properties, and it has chemical resistance that can withstand the photolithography process. . Therefore, the resin precursor is suitable for use in a transparent substrate of a flexible display.

  More specifically, when forming a flexible display, a glass substrate is used as a support, a flexible substrate is formed thereon, and TFTs and the like are formed thereon. The process of forming the TFT on the substrate is typically performed in a wide temperature range of 150 to 650 ° C. However, in order to realize a desired performance, the process is mainly performed at 250 ° C. to 350 ° C. A TFT-IGZO (InGaZnO) oxide semiconductor or a TFT (a-Si-TFT, poly-Si-TFT) is formed using an inorganic material.

  At this time, if the residual stress generated in the flexible substrate and the polyimide film is high, when the glass substrate expands in the high temperature TFT process and then shrinks when cooled at room temperature, the glass substrate may be warped or damaged, and the flexible substrate may be peeled from the glass substrate. The problem arises. Generally, the coefficient of thermal expansion of a glass substrate is smaller than that of resin, so that residual stress occurs between the glass substrate and the flexible substrate. In consideration of this point, the resin film according to the present embodiment preferably has a residual stress of 25 MPa or less between the resin film and the glass, based on the film thickness of 10 μm.

  Further, the resin film according to the present embodiment has a yellowness of 7 or less on the basis of the film thickness of 20 μm, and the transmittance was measured by an ultraviolet spectrophotometer on the basis of the film thickness of 20 μm. In this case, the transmittance at 550 nm is preferably 85% or more. Further, it is advantageous to obtain a resin film having a low YI value in a stable manner when the oxygen concentration dependency in the oven used for producing the thermosetting film is low. It is preferable that the YI value of the film is stable.

  Further, the resin film according to the present embodiment has a mechanical elongation of 30% or more on the basis of the film thickness of 20 μm, from the viewpoint of improving the yield by being excellent in breaking strength when handling a flexible substrate. Is more preferable.

  Further, the resin film according to the present embodiment preferably has a glass transition temperature of 250 ° C. or higher in order to prevent softening of the resin substrate at the temperature for manufacturing the TFT element.

  In addition, the resin film according to the present embodiment preferably has chemical resistance that can withstand a photoresist stripping solution in a photolithography process used when manufacturing a TFT element.

  There are two types of light extraction methods for a flexible display: a top emission method that extracts light from the front surface side of the TFT element and a bottom emission method that extracts light from the back surface side. The top emission method has a feature that the aperture ratio can be easily increased because the TFT element does not get in the way, and the bottom emission method has a feature that alignment is easy and manufacturing is easy. If the TFT element is transparent, the aperture ratio can be improved even in the bottom emission method, so it is expected that the bottom emission method, which is easy to manufacture, will be adopted in the large organic EL flexible display. There is. When a resin substrate is used as the colorless transparent resin substrate used for the bottom emission method, the resin substrate comes on the side to be visually recognized, so that optical isotropicity, that is, retardation in the thickness direction (Rth ) Is required to be low from the viewpoint of improving image quality. Further, when used in the top emission system, it is not required that Rth is low, but from the viewpoint of being commonly applicable to both systems, a material having low Rth is preferable. Specifically, based on the film thickness of 20 μm, 200 nm or less is preferable, 90 nm or less is more preferable, 80 nm or less is further preferable, and 50 nm or less is particularly preferable. If Rth is 100 nm or less, and further 90 nm or less, it satisfies the performance not only for the top emission type transparent display transparent substrate but also for the bottom emission type flexible display transparent substrate and touch panel electrode substrate. ing.

Another aspect of the present invention provides a polyimide resin film used for manufacturing a display substrate, wherein the Rth in a thickness of 20 μm is 20 to 90 nm.
Another aspect of the present invention is a step of developing a resin composition containing a polyimide precursor on the surface of a support,
A step of heating the support and the resin composition to imidize the polyimide precursor to form the polyimide resin film described above;
A step of forming an element on the polyimide resin film,
And a step of peeling the polyimide resin film having the element formed thereon from the support, to provide a method for manufacturing a display substrate.

  The resin film according to the present embodiment satisfying the above-mentioned physical properties is suitably used as an application whose use is limited by the yellow color of the existing polyimide film, especially as a colorless transparent substrate for a flexible display. Furthermore, for example, a protective film or a light-scattering sheet and a coating film in a TFT-LCD (for example, an interlayer of a TFT-LCD, a gate insulating film, and a liquid crystal alignment film), an ITO substrate for a touch panel, a cover glass substitute resin for a smartphone. It can also be used in fields such as substrates that require colorless transparency and low birefringence. When the polyimide according to the present embodiment is applied as the liquid crystal alignment film, it contributes to the increase of the aperture ratio, and it is possible to manufacture a TFT-LCD having a high contrast ratio.

  The resin film and the laminate manufactured using the resin precursor according to the present embodiment are particularly suitable for manufacturing a semiconductor insulating film, a TFT-LCD insulating film, an electrode protective film, and a flexible device, particularly as a substrate. Can be used for. Here, the flexible device may include, for example, a flexible display, a flexible solar cell, a flexible touch panel electrode substrate, flexible lighting, and a flexible battery.

Hereinafter, the present invention will be described in more detail based on examples, but these are described for the purpose of description, and the scope of the present invention is not limited to the following examples.
Various evaluations in Examples and Comparative Examples were performed as follows.

(Measurement of weight average molecular weight)
The weight average molecular weight (Mw) was measured by gel permeation chromatography (GPC) under the following conditions. As the solvent, N, N-dimethylformamide (manufactured by Wako Pure Chemical Industries, for high performance liquid chromatography) was used, and before measurement, 24.8 mmol / L lithium bromide monohydrate (manufactured by Wako Pure Chemical Industries, Ltd. , Purity 99.5%) and 63.2 mmol / L phosphoric acid (manufactured by Wako Pure Chemical Industries, for high performance liquid chromatography) were used. A calibration curve for calculating the weight average molecular weight was prepared using standard polystyrene (manufactured by Tosoh Corporation).

Column: Shodex KD-806M (manufactured by Showa Denko KK)
Flow rate: 1.0 mL / min Column temperature: 40 ° C
Pump: PU-2080Plus (made by JASCO)
Detector: RI-2031Plus (RI: differential refractometer, manufactured by JASCO)
UV-2075Plus (UV-VIS: UV-Visible Absorber, JASCO)

(Silicon group-containing monomer concentration)
The silicon group-containing monomer concentration was calculated from the following formula using the masses of the silicon group-containing monomer, the polyvalent carboxylic acid or its derivative, and the diamine compound used in synthesizing the resin precursor.
Silicon group-containing monomer concentration (%) = silicon group-containing monomer mass /
(Mass of silicon group-containing monomer + mass of polycarboxylic acid or its derivative + mass of diamine compound) × 100

(Production of laminate and isolated film)
The resin composition is applied to a non-alkali glass substrate (thickness 0.7 mm) with a bar coater, leveling is performed at room temperature for 5 minutes to 10 minutes, and a vertical cure oven (manufactured by Koyo Lindbergh, model name VF-2000B). Was heated at 140 ° C. for 60 minutes and further heated at 350 ° C. for 60 minutes in a nitrogen atmosphere to produce a laminate. At this time, the oxygen concentration in the hot air oven was adjusted to 50 ppm, 100 ppm, and 500 ppm, respectively, and the oxygen concentration dependence of the YI value and the total light transmittance was examined. The film thickness of the resin composition of the laminate was 20 μm. After curing (curing treatment) at 350 ° C., the laminate was left at room temperature for 24 hours, the resin film was peeled from the glass, and the film was isolated. For the evaluations other than the yellowness degree and the total light transmittance below, a resin film obtained by adjusting the oxygen concentration in the hot air oven to 100 ppm and curing at 350 ° C. for 60 minutes was used as a sample.

(Evaluation of tensile elongation)
A resin film having a sample length of 5 × 50 mm and a thickness of 20 μm, which was cured at 350 ° C., was pulled at a speed of 100 mm / min using a tensile tester (manufactured by A & D Co., Ltd .: RTG-1210), and the tensile elongation was measured. .

(Yellowness, total light transmittance and its oxygen concentration dependency during curing)
The oxygen concentration in the oven was adjusted to 50 ppm, 100 ppm, and 500 ppm, respectively, and a resin film having a thickness of 20 μm, which was cured at 350 ° C., was manufactured by Nippon Denshoku Industries Co., Ltd. (Spectrophotometer: SE600) using a D65 light source. Yellowness (YI value) and total light transmittance were measured.

(Evaluation of thickness direction retardation (Rth))
The resin film having a thickness of 20 μm, which was cured at 350 ° C., was measured using a retardation birefringence measuring device (KOBRA-WR manufactured by Oji Scientific Instruments Co., Ltd.). The wavelength of the measurement light was 589 nm.

(Evaluation of glass transition temperature and coefficient of linear expansion)
Regarding the measurement of the glass transition temperature (called Tg (1)) and the linear expansion coefficient (CTE) in the room temperature range or higher, a resin film having a sample length of 5 × 50 mm and a thickness of 20 μm, which was cured at 350 ° C., was manufactured by Shimadzu Corporation. By thermomechanical analysis using a mechanical analyzer (TMA-50), the load of 5 g, the heating rate of 10 ° C./min, the nitrogen atmosphere (flow rate of 20 ml / min), and the elongation of the test piece in the temperature range of 50 to 450 ° C. The measurement was performed, the inflection point was determined as the glass transition temperature, and the CTE of the heat resistant resin film at 100 to 250 ° C. was determined.

  Since it is impossible to measure the glass transition temperature (called Tg (2)) in the room temperature range or lower by the above method, the above resin film is used in the dynamic viscoelasticity measuring device (−150 ° C. to 400 ° C.). The inflection point of E-prime in the temperature range below room temperature was measured by RHEOVIBRON MODEL RHEO-1021 manufactured by Orientec Co., Ltd., and the inflection point was determined as the glass transition temperature at low temperature.

(Evaluation of residual stress)
Using a residual stress measuring device (manufactured by Tencor Co., model name FLX-2320), the resin composition was applied by a bar coater onto a 6-inch silicon wafer having a thickness of 625 μm ± 25 μm whose “warpage amount” was measured in advance. After coating and pre-baking at 140 ° C. for 60 minutes, a vertical curing furnace (manufactured by Koyo Lindbergh, model name VF-2000B) is used to perform heat curing treatment at 350 ° C. for 1 hour in a nitrogen atmosphere, and after curing. A silicon wafer with a resin film having a film thickness of 10 μm was produced. The amount of warp of this wafer was measured using the above-mentioned residual stress measuring device, and the residual stress generated between the silicon wafer and the resin film was evaluated.

(Evaluation of chemical resistance test)
A resin film piece having a thickness of 20 μm, which was cured at 350 ° C., was immersed in an NMP layer at room temperature, pulled up every 10 minutes, washed with ion-exchanged water, and then the film surface was observed with a microscope to find cracks on the surface of the thermosetting film. The entry time was evaluated in 10 minute increments up to 300 minutes.

[Example 1]
To a 3 L separable flask equipped with a stir bar equipped with an oil bath, NMP of 1000 g was added while introducing nitrogen gas, and 3,3- (diaminodiphenyl) sulfone (defined as diamine 1) was added of 232.4 g with stirring. Subsequently, 218.12 g of pyromellitic dianhydride (defined as tetracarboxylic acid anhydride 1) was added, and the mixture was stirred at room temperature for 30 minutes. After heating this to 50 ° C. and stirring for 12 hours, both ends amine-modified methylphenyl silicone oil (Shin-Etsu Chemical Co., Ltd .: X22-1660B-3 (number average molecular weight 4400)) (defined as silicon group-containing diamine). 105.6 g was dissolved in 298 g NMP and added dropwise using a dropping funnel. After heating to 80 ° C. and stirring for 1 hour, the oil bath was removed and the temperature was returned to room temperature to obtain a transparent NMP solution of polyamic acid (hereinafter also referred to as varnish). The composition here and the weight average molecular weight (Mw) of the obtained polyamic acid are shown in Table 1. Table 4 shows the test results of the film cured at 350 ° C.

[Examples 2-33, 49-58]
In the same manner as in Example 1, except that the types of diamine 1, tetracarboxylic acid anhydride 1, silicon group-containing diamine, and the addition masses thereof were changed to those shown in Table 1, respectively, the same operation as in Example 1 was performed. I went and got a varnish. Moreover, the NMP addition amount shown in Table 1 and Table 2 shows the total amount of NMP finally contained in the varnish, and is a mass containing 298 g of NMP for diluting the silicon group-containing diamine. The composition here and the weight average molecular weight (Mw) of the obtained polyamic acid are shown in Table 1, Table 2, and Table 7, respectively. The test results of the film cured at 350 ° C. are shown in Table 4, Table 5 and Table 8, respectively. The official compound names of the abbreviated compound names shown in Tables 1 to 6 are shown below.
3,3-DAS: 3,3- (diaminodiphenyl) sulfone 4,4-DAS: 4,4- (diaminodiphenyl) sulfone 3,4-DAS: 3,4- (diaminodiphenyl) sulfone PMDA: pyromellitic acid Dianhydride ODPA: 4,4'-oxydiphthalic acid dianhydride 6FDA: 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride BPDA: 3,3', 4,4'-biphenyltetracarboxylic dianhydride Compound CHDA: cyclohexane-1,2,4,5-tetracarboxylic dianhydride DSDA: 3,3 ', 4,4'-diphenylsulfone tetracarboxylic dianhydride BPADA: 2,2-bis [4- ( 3,4-Dicarboxyphenoxy) phenyl] propane dianhydride BPAF: 9,9′-bis (3,4-dicarboxyphenyl) fluorene dinone Things TAHQ: 4,4'- biphenyl-bis (trimellitic acid monoester acid anhydride)
BTDA: 3,3 ', 4,4'-benzophenone tetracarboxylic acid dianhydride TPE-R: 1,3-bis (4-aminophenoxy) benzene CBDA: 1,2,3,4-cyclobutane tetracarboxylic acid dianhydride Anhydrous FM3311: Amine-modified dimethyl silicone oil at both ends (Cilaso FM3311 manufactured by Chisso Corporation (number average molecular weight 1000))
TFMB: 2,2'-bis (trifluoromethyl) benzidine TACl: trimellitic anhydride chloride

Example 34
Nitrogen gas was introduced into a 3 L separable flask with a stirring rod equipped with an oil bath, 1274 g of NMP was added, and 4,4′-oxydiphthalic acid dianhydride (hereinafter referred to as ODPA) (defined as tetracarboxylic acid anhydride 1). Is added, and 105.6 g of amine-modified methylphenyl silicone oil (X22-1660B-3 (number average molecular weight 4400) manufactured by Shin-Etsu Chemical Co., Ltd.) (defined as a silicon group-containing diamine) is dissolved in 298 g of NMP with stirring. What was done was dripped using the dropping funnel. After stirring at room temperature for 1 hour, 149.9 g of 2,2′-bis (trifluoromethyl) benzidine (hereinafter referred to as TFMB) (defined as diamine 2) was added with stirring, and subsequently 3,3-DAS was added. 116.2 g was added with stirring, and the mixture was stirred at room temperature for 1 hour. Subsequently, the temperature was raised to 50 ° C., 147.1 g of BPDA (defined as tetracarboxylic acid anhydride 2) was added, and the mixture was stirred for 12 hours. This was heated to 80 ° C. and stirred for 4 hours, then the oil bath was removed and the temperature was returned to room temperature to obtain a transparent NMP solution of polyamic acid (hereinafter, also referred to as varnish). Table 2 shows the composition here and the weight average molecular weight (Mw) of the obtained polyamic acid. Table 5 shows the test results of the film cured at 350 ° C.

[Examples 35, 39, 40, 44, 45]
In the same manner as in Example 34, the types of diamine 1, diamine 2, tetracarboxylic acid anhydride 1, tetracarboxylic acid anhydride 2 and their addition masses were changed to those shown in Table 2, respectively, and Example 34 was used. A varnish was obtained by performing the same operation as above. Moreover, the NMP addition amount shown in Table 2 shows the total amount of NMP finally contained in the varnish, and is a mass containing 298 g of NMP for diluting the silicon group-containing diamine. The composition here and the weight average molecular weight (Mw) of the obtained polyamic acid are shown in Table 2. Table 5 shows the test results of the films cured at 350 ° C.

Example 36
While introducing nitrogen gas, 1196 g of N-methylpyrrolidone (hereinafter referred to as NMP) was added to a 3 L separable flask with a stirring rod equipped with an oil bath, and 3,3- (diaminodiphenyl) sulfone (defined as diamine 1). 232.4 g with stirring, and after heating to 50 ° C., 147.1 g of BPDA (defined as tetracarboxylic acid anhydride 1) was added and stirred for 30 minutes. Subsequently, 155.1 g of ODPA (defined as tetracarboxylic acid anhydride 2) was added, and the mixture was stirred for 8 hours, and then amine-modified methylphenyl silicone oil (both manufactured by Shin-Etsu Chemical Co., Ltd .: X22-1660B-3 (number average molecular weight 4400). )) (Defined as silicon group-containing diamine) 105.6 g was dissolved in NMP 298 g and added dropwise using a dropping funnel. After heating to 80 ° C. and stirring for 1 hour, the oil bath was removed and the temperature was returned to room temperature to obtain a transparent NMP solution of polyamic acid (hereinafter also referred to as varnish). Table 2 shows the composition here and the weight average molecular weight (Mw) of the obtained polyamic acid. Table 5 shows the test results of the film cured at 350 ° C.

[Examples 37, 42, 43, 46, 47]
In the same manner as in Example 36, the types of diamine 1, tetracarboxylic acid anhydride 1, and tetracarboxylic acid anhydride 2 and the addition masses thereof were changed to those shown in Table 2, respectively, and the same as in Example 36. The operation was performed to obtain a varnish. Moreover, the NMP addition amount shown in Table 2 shows the total amount of NMP finally contained in the varnish, and is a mass containing 298 g of NMP for diluting the silicon group-containing diamine. The composition here and the weight average molecular weight (Mw) of the obtained polyamic acid are shown in Table 2. Table 5 shows the test results of the films cured at 350 ° C.

[Example 38]
To a 3 L separable flask equipped with a stir bar equipped with an oil bath, 1200 g of NMP was added while introducing nitrogen gas, and 3,3- (diaminodiphenyl) sulfone (defined as diamine 1) was added with stirring of 232.4 g, After heating to 50 ° C., 40.6 g of terephthaloyl chloride (defined as other monomer component) was dissolved in 200 g of γ-butyrolactone, added dropwise and stirred for 30 minutes. Subsequently, 235.4 g of BPDA (defined as tetracarboxylic acid anhydride 1) was added and stirred for 8 hours, and then amine phenyl silicone oil modified with amine at both ends (X22-1660B-3 manufactured by Shin-Etsu Chemical Co., Ltd. (number average molecular weight 4400). )) (Defined as silicon group-containing diamine) 105.6 g was dissolved in NMP 298 g and added dropwise using a dropping funnel. After heating to 80 ° C. and stirring for 1 hour, the oil bath was removed and the temperature was returned to room temperature to obtain a transparent polyamic acid solution. After adding 1000 g of NMP and diluting it, it was added dropwise to 10 L of ion-exchanged water to deposit a powder of the polyamideimide precursor, and then the powder was filtered with a Buchner funnel. This powder was vacuum dried at 40 ° C. for 48 hours. To the powder thus obtained, 1403 g of NMP was added to obtain an NMP solution of a polyamideimide precursor. Table 2 shows the composition here and the weight average molecular weight (Mw) of the obtained polyamideimide precursor. Table 5 shows the test results of the film cured at 350 ° C.

[Examples 43 and 48]
In the same manner as in Example 38, the same operation as in Example 38 was performed, except that the types of diamine 1, tetracarboxylic acid anhydride 1, other monomer components, and the addition masses thereof were changed to those shown in Table 2. Got a varnish. Moreover, the NMP addition amount shown in Table 2 shows the total amount of NMP finally contained in the varnish. The composition here and the weight average molecular weight (Mw) of the obtained polyamideimide precursor are shown in Table 2, respectively. Table 5 shows the test results of the films cured at 350 ° C.

[Example 59]
Into a 3 L separable flask equipped with a stir bar equipped with an oil bath, NMP of 1000 g was added while introducing nitrogen gas, and 3,3- (diaminodiphenyl) sulfone (defined as diamine 1) was added with stirring of 248.30 g, Subsequently, 275.13 g of BPDA (defined as tetracarboxylic acid anhydride 1) was added, and the mixture was stirred at room temperature for 30 minutes. This was heated to 50 ° C. and stirred for 12 hours, and then 104.58 g of NMP298g of both ends acid anhydride modified methylphenyl silicone oil (Shin-Etsu Chemical Co., Ltd .: X22-168-P5-B (number average molecular weight 4200)) And was added dropwise using a dropping funnel. After heating to 80 ° C. and stirring for 1 hour, the oil bath was removed and the temperature was returned to room temperature to obtain a transparent NMP solution of polyamic acid (hereinafter also referred to as varnish). Table 7 shows the composition here and the weight average molecular weight (Mw) of the obtained polyamic acid. Table 8 shows the test results of the film cured at 350 ° C.

[Examples 60 to 66]
In the same manner as in Example 59, the types of diamine 1, tetracarboxylic acid anhydride 1, silicon group-containing diamine, and the addition masses thereof were changed to those shown in Table 1, respectively, and the same operation as in Example 1 was performed. I went and got a varnish. Moreover, the NMP addition amount shown in Table 1 and Table 2 shows the total amount of NMP finally contained in the varnish, and is a mass containing 298 g of NMP for diluting the silicon group-containing diamine. The composition here and the weight average molecular weight (Mw) of the obtained polyamic acid are shown in Table 7, respectively. Table 8 shows the test results of the films cured at 350 ° C.

[Comparative Example 1]
To a 3 L separable flask with a stirring rod equipped with an oil bath, while introducing nitrogen gas, 1065 g of NMP was added, and 3,3- (diaminodiphenyl) sulfone (defined as diamine 1) was added while stirring 248.3 g, Subsequently, 218.12 g of pyromellitic dianhydride (defined as tetracarboxylic acid anhydride 1) was added, and the mixture was stirred at room temperature for 30 minutes. This was heated to 50 ° C. and stirred for 12 hours, then the oil bath was removed and the temperature was returned to room temperature to obtain a transparent NMP solution of polyamic acid (hereinafter, also referred to as varnish). Table 3 shows the composition and the weight average molecular weight (Mw) of the obtained polyamic acid. Table 6 shows the test results of the film cured at 350 ° C.

[Comparative Examples 2 to 21]
In the same manner as in Comparative Example 1, the types of diamine 1 and tetracarboxylic acid anhydride 1 and their added masses were changed to those shown in Table 3, respectively, and the same operation as in Comparative Example 1 was performed to obtain a varnish. It was The composition here and the weight average molecular weight (Mw) of the obtained polyamic acid are shown in Table 3, respectively. Table 6 shows the test results of the films cured at 350 ° C.

[Comparative Example 22]
Nitrogen gas was introduced into a 3 L separable flask equipped with a stir bar equipped with an oil bath, 1332 g of NMP was added, 299.8 g of TFMB (defined as diamine 2) was added with stirring, and 294.2 g of BPDA (tetracarboxylic acid anhydride was added. 1)), heated to 50 ° C., and stirred for 12 hours. To this, a solution obtained by dissolving 105.6 g of an amine-modified methylphenyl silicone oil (both manufactured by Shin-Etsu Chemical Co., Ltd .: X22-1660B-3 (number average molecular weight 4400)) (defined as a silicon group-containing diamine) in 298 g of NMP was added to the dropping funnel. Was added dropwise. After the dropping was completed, the temperature was raised to 80 ° C., the mixture was stirred for 1 hour, the oil bath was removed, and the temperature was returned to room temperature to obtain an opaque NMP solution of polyamic acid (hereinafter, also referred to as a varnish) with some turbidity. Table 3 shows the composition and the weight average molecular weight (Mw) of the obtained polyamic acid. Table 6 shows the test results of the film cured at 350 ° C.

[Comparative Example 23]
Pyromellitic anhydride (PMDA) 4.3 g (0.02 mol) and BTDA 25.78 g were dispersed in N-methyl-2-pyrrolidone (NMP) 240 g to give ω-ω'-bis- (3-aminopropyl) polydimethyl. A solution obtained by dissolving 2.4 g of siloxane (average molecular weight of 480) in 50 g of diethylene glycol dimethyl ether (Dig) was added dropwise little by little and stirred for 1 hour to react. Thus, after reacting diaminosiloxane and tetracarboxylic dianhydride, 14.62 g (0.05 mol) of 1,3-bis (4-aminophenoxy) benzene (TPE-R), and then 3,3DAS11. 17 g was added in small portions as a powder.

[Comparative Example 24]
A 1-liter flask equipped with a stirrer, a dropping funnel, a thermometer, a condenser and a nitrogen purging device was fixed in cold water. After purging the flask with nitrogen gas, 500 g of dehydrated and purified N-methyl-2-pyrrolidone (hereinafter abbreviated as NMP) and 3,3′4,4′-benzophenonetetracarboxylic dianhydride (BTDA) 25.11 g (0.0779 mol), 15.48 g (0.0623 mol) of 3,3'-diaminodiphenyl sulfone (3,3-DAS) and ω-ω'-bis- (3-aminopropyl) poly 14.96 g (0.0159 mol) of dimethylsiloxane (molecular weight 960) was mixed and a polyamic acid solution was obtained according to a conventional method.

[Comparative Example 25]
A 300 mL four-necked flask equipped with a thermometer, a stirrer, a nitrogen introducing tube, and a cooling tube was fitted with 2.87 g (25.1 mmol) of 1,4-diaminocyclohexane as a diamine compound and amino-terminal modified methylphenyl silicone (X22-1660B). -3) 3.42 g (0.8 mmol) was added. Then, after replacing the inside of the flask with nitrogen, 58 ml of N, N-dimethylacetamide was added and stirred until uniform. 8.71 g (25.9 mmol) of diphenyl-3,3 ′, 4,4′-tetracarboxylic dianhydride (BPDA) as a polyvalent carboxylic acid derivative was added to the obtained solution at room temperature, and the temperature was maintained at 24. Stirring was continued for a while to obtain a composition (polyamic acid solution).

[Comparative Example 26]
4,4'-diamino-2,2'-bis (trifluoromethyl) biphenyl (hereinafter referred to as "TFMB") as a component (B) in a 300 mL four-necked flask equipped with a thermometer, a stirrer, a nitrogen introducing tube, and a cooling tube. 7.85 g (24.5 mmol) and 2.03 g (1.6 mmol) of amino-terminal modified methyl phenyl silicone (X22-9409) were added. Then, after replacing the inside of the flask with nitrogen, 58 ml of N, N-dimethylacetamide was added and stirred until uniform. To the resulting solution, 5.12 g (26.1 mmol) of 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride (hereinafter also referred to as "CBDA") was added as a component (A) at room temperature, and the temperature was kept as it was. The stirring was continued for 24 hours to obtain a composition (polyamic acid solution).

  The YI values and the total light transmittances shown in Tables 4 to 6 and Table 8 show the results (50 ppm / 100 ppm / 500 ppm) when the oxygen concentrations in the oven were adjusted to 50 ppm, 100 ppm, and 500 ppm, respectively. .

  As shown in Tables 4, 5, and 8, it was confirmed that Examples 1 to 66 simultaneously satisfy the following conditions in film physical properties.

(1) Residual stress is 25 MPa or less (2) Yellowness is 7 or less and is less affected by oxygen concentration (3) Glass transition temperature is 250 ° C. or higher in a temperature range of room temperature or higher (4) Total light transmittance is 88% or more and less affected by oxygen concentration (5) Tensile elongation 30% or more (6) NMP chemical resistance test 30 minutes or more (7) Even if a varnish is made with NMP alone, the thermosetting film becomes cloudy High total light transmittance

  These satisfy the performance for applying to the transparent substrate for the top emission type flexible display.

  In Examples 1 to 33, 36, 37, 41, 42, 46, 47, and 53 to 66, the retardation Rth in the film thickness direction due to birefringence is 100 nm or less (20 to 90 nm), which is a top emission type. It satisfies not only the transparent substrate for flexible displays, but also the performance for application to bottom emission type transparent substrates for flexible displays and touch panel electrode substrates. In addition, the retardation Rth in the thickness direction is a polyimide that does not use a silicon group-containing monomer as a copolymerization monomer (Comparative Examples 1 to 22) and a polyimide that uses a silicon group containing monomer (Examples 1 to 33). From the comparison, it can be seen that the polyimide using the silicon group-containing monomer has a smaller Rth, and the silicon group-containing monomer contributes to the reduction of the Rth of the polyimide.

  On the other hand, Comparative Examples 1 to 26 have low residual stress, chemical resistance, and tensile elongation, and the YI value and the total light transmittance are affected by the oxygen concentration during curing and deteriorate.

  From these results, the resin obtained from the resin precursor according to the present invention is colorless and transparent, has a low residual stress generated between the resin and the inorganic film, is further excellent in chemical resistance, and has a YI depending on the oxygen concentration during curing. It was confirmed that the resin film had a small effect on the value and the total light transmittance.

  The present invention is not limited to the above-mentioned embodiment, and can be implemented with various modifications.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used, for example, as a semiconductor insulating film, a TFT-LCD insulating film, an electrode protective film, a flexible display manufacturing, a touch panel ITO electrode substrate, and particularly as a substrate.

Claims (27)

A resin precursor obtained by polymerizing a polymerization component containing an amino group and an amino group reactive group,
The polymerization component contains a polyvalent compound having two or more groups selected from an amino group and an amino group-reactive group,
The polyvalent compound includes a silicon group-containing compound,
The polyvalent compound has the following formula (1):

Including a diamine represented by
The resin precursor has the following general formula (2):

{In the formula, a plurality of R ₃ and R _{4 present} are each independently a monovalent organic group having 1 to 20 carbon atoms, and h is an integer of 3 to 200. } Has a structure represented by
The amount of the silicon group-containing compound is 6% by mass to 25% by mass based on the total mass of the polyvalent compound,
The resin precursor.   The resin precursor according to claim 1, wherein the amino group-reactive group includes one or more selected from the group consisting of a carboxyl group, a substituted carboxyl group and an acid anhydride group. The silicon group-containing compound has the following general formula (3):

{In the formula, a plurality of R _2's each independently represent a single bond or a divalent organic group having 1 to 20 carbon atoms, and R ₃ and R ₄ each independently represent one of 1 to 20 carbon atoms. R ₅ which is a valent organic group and may be present in plural numbers are each independently a monovalent organic group having 1 to 20 carbon atoms, and L ₁ , L ₂ and L ₃ are each independently It is an amino group, an isocyanate group, a carboxyl group, an acid anhydride group, an acid ester group, an acid halide group, a hydroxy group, an epoxy group, or a mercapto group, j is an integer of 3 to 200, and k is 0 to 0. It is an integer of 197. } The resin precursor of Claim 1 or 2 containing the silicone compound represented by these. The resin precursor according to claim 3, wherein in the general formula (3), L ₁ and L ₂ are each independently an amino group or an acid anhydride group, and k is 0. The resin precursor according to claim 4, wherein both L ₁ and L ₂ in the general formula (3) are amino groups. The resin precursor contains a unit 1 and a unit 2,
The unit 1 has at least the following general formula (4);

{In the formula, R ₁ existing in plural, each independently, a hydrogen atom, an aliphatic hydrocarbon, or a monovalent aromatic group having a monovalent C1-20, optionally X ₁ be a plurality of present Are each independently a tetravalent organic group having 4 to 32 carbon atoms, and n is an integer of 1 to 100. } Has a structure represented by
The unit 2 has the following general formula (5):

{In the formula, a plurality of R _1's are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or a monovalent aromatic group, and a plurality of R _2's are respectively Independently, it is a divalent aliphatic hydrocarbon having 3 to 20 carbon atoms or a divalent aromatic group, and R ₃ and R ₄ are each independently a monovalent organic group having 1 to 20 carbon atoms. X ₂ , which may be present, are each independently a tetravalent organic group having 4 to 32 carbon atoms, l is an integer of 3 to 50, and m is an integer of 1 to 100. Is. } Or the following general formula (6):

{In the formula, a plurality of R ₁ are each independently a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or a monovalent aromatic group, and a plurality of R ₃ and R _{4 are present.} Are each independently a monovalent organic group having 1 to 20 carbon atoms, and a plurality of R ₈ are each independently an trivalent aliphatic hydrocarbon having 3 to 20 carbon atoms or a trivalent aromatic group. Is a group group, p is an integer from 1 to 100, and q is an integer from 3 to 50. } The structure represented by these, or both the structure represented by the said General formula (5), and the structure represented by the said General formula (6), It has any one of Claims 1-5. Resin precursor.   The resin precursor according to claim 6, wherein the total amount of the unit 1 and the unit 2 is 30% by mass or more based on the total mass of the resin precursor. The resin precursor has the following general formula (7):

{In the formula, R ₁ existing in plural, each independently, a hydrogen atom, a monovalent aliphatic hydrocarbon having 1 to 20 carbon atoms, or an aromatic group of monovalent, optionally X ₃ be plurality of Are each independently a divalent organic group having 4 to 32 carbon atoms, and a plurality of X ₄ which may be present are each independently a tetravalent organic group having 4 to 32 carbon atoms, and t Is an integer of 1 to 100. } The resin precursor according to claim 6 or 7, further containing a unit 3 having a structure represented by the following formula. The resin precursor according to claim 8, wherein in the general formula (7), X ₃ is a residue having a structure in which an amino group is removed from 2,2′-bis (trifluoromethyl) benzidine. The unit 1 and the unit 2 are
A moiety derived from one or more selected from the group consisting of pyromellitic dianhydride (PMDA) and biphenyltetracarboxylic dianhydride (BPDA);
4,4'-oxydiphthalic dianhydride (ODPA), 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride (6FDA), cyclohexane-1,2,4,5-tetracarboxylic dianhydride ( CHDA), 3,3 ', 4,4'-diphenylsulfone tetracarboxylic acid dianhydride (DSDA), 4,4'-biphenylbis (trimellitic acid monoester acid anhydride) (TAHQ), and 9,9. A portion that is a combination with a portion derived from one or more selected from the group consisting of'-bis (3,4-dicarboxyphenyl) fluorene dianhydride (BPAF) is used as the acid diamine of the unit 1 and the unit 2. The resin precursor according to any one of claims 6 to 9, which is contained in an amount of 60 mol% or more based on the total amount of the anhydride-derived sites. The R ₃ and the R ₄ are each independently a monovalent aliphatic hydrocarbon group having 1 to 3 carbon atoms or a monovalent aromatic hydrocarbon group having 6 to 10 carbon atoms. 10. The resin precursor according to any one of 10. The resin precursor according to claim 1, wherein at least part of R ₃ and R ₄ is a phenyl group.   The resin obtained by heating and curing the resin precursor under an inert atmosphere at 300 to 500 ° C. has at least one glass transition temperature in the range of −150 ° C. to 0 ° C. and at least in the range of 150 ° C. to 380 ° C. The resin precursor according to any one of claims 1 to 12, which has one glass transition temperature and does not have a glass transition temperature in a region higher than 0 ° C and lower than 150 ° C.   The resin according to any one of claims 1 to 13, which contains 20 mol% or more of sites derived from biphenyltetracarboxylic dianhydride (BPDA), based on the total amount of sites derived from the acid dianhydride of the resin precursor. precursor.   The resin precursor according to any one of claims 1 to 14, which is partially imidized. The resin precursor according to claim 1, and the following general formula (8):

{In the formula, a plurality of X ₃ which may be present are each independently a tetravalent organic group having a carbon number of 4 to 32, and a plurality of R ₁ are independently a hydrogen atom and a carbon number of 1 to 1 20 monovalent aliphatic hydrocarbons, or monovalent aromatic groups, and r is an integer from 1 to 100. } The precursor mixture containing the resin precursor which has a structure represented by these.   A flexible device material comprising the resin precursor according to any one of claims 1 to 15 or the precursor mixture according to claim 16.   A resin film, which is a cured product of the resin precursor according to any one of claims 1 to 15 or a cured product of the precursor mixture according to claim 16.   A resin composition comprising the resin precursor according to any one of claims 1 to 15 or the precursor mixture according to claim 16 and a solvent.   A resin obtained by imidizing the resin precursor contained in the resin composition by heating the resin composition at 300 ° C. to 500 ° C. under a nitrogen atmosphere after developing the resin composition on the surface of a support. The resin composition according to claim 19, which has a yellowness index of 7 or less at a film thickness of 20 μm.   A resin obtained by imidizing the resin precursor contained in the resin composition by heating the resin composition at 300 ° C. to 500 ° C. under a nitrogen atmosphere after developing the resin composition on the surface of a support. The resin composition according to claim 19 or 20, wherein the residual stress at a film thickness of 10 μm is 25 MPa or less.   A resin film, which is a cured product of the resin composition according to any one of claims 19 to 21. A step of developing the resin composition according to any one of claims 19 to 21 on a surface of a support,
A step of heating the support and the resin composition to form a resin film by imidizing the resin precursor contained in the resin composition;
A step of peeling the resin film from the support,
A method for producing a resin film, comprising:   A laminate comprising a support and a resin film, which is a cured product of the resin composition according to any one of claims 19 to 21, formed on the surface of the support. Spreading the resin composition according to any one of claims 19 to 21 on the surface of a support,
Heating the support and the resin composition to imidize the resin precursor contained in the resin composition to form a resin film, thereby obtaining a laminate including the support and the resin film; ,
A method for producing a laminate, including:   A polyimide resin film used for manufacturing a display substrate, wherein the Rth in a thickness of 20 μm is 20 to 90 nm. A step of developing a resin composition containing a polyimide precursor on the surface of the support,
A step of heating the support and the resin composition to imidize a polyimide precursor to form a polyimide resin film according to claim 26;
A step of forming an element on the polyimide resin film,
And a step of peeling the polyimide resin film on which the element is formed from the support.