JP7222626B2 - COMPOSITION, CURED PRODUCT, METHOD FOR PRODUCING CURED PRODUCT, SALT, AND AGENT FOR Suppressing Aging Over Time Of Polyimide Film-Forming Composition And For Improving Film Formability - Google Patents

Description

The present invention provides a composition suitable for forming a polyimide film, a cured product of the composition, a method for producing a cured product using the composition, a salt, and a polyimide film-forming composition for suppressing aging and improving film-forming properties. Regarding agents.

Polyimide resin has properties such as excellent heat resistance, mechanical strength, insulation, and low dielectric constant. It is widely used as a material and protective material.

Polyimide resins are generally formed by heat-treating a polyamic acid obtained by polymerizing a tetracarboxylic dianhydride component and a diamine component in a polar organic solvent. Against this background, polyimide products for electronic materials are often supplied as solutions of polyimide precursors such as polyamic acid. Specifically, when manufacturing electric and electronic parts, a solution of a polyimide precursor is supplied by a method such as coating or injection to a place where an insulating material or a protective material is to be formed, and then the solution of the polyimide precursor is is heat-treated to form an insulating material and a protective material.

Technological developments related to such polyimide resins have also been earnestly pursued.
For example, Patent Document 1 discloses a resin composition containing a polyamic acid and a basic nitrogen-containing compound for the purpose of improving film formability.

JP 2018-58918 A

However, the present inventors have found that a resin composition containing a polyamic acid and a basic nitrogen-containing compound changes over time and deteriorates if left for several days after preparation.
There is a demand for a composition that is excellent in both film-forming properties and stability over time.

In view of the above problems of the prior art, the present invention provides a composition excellent in film-forming properties and stability over time, a cured product of the composition, a method for producing a cured product using the composition, a salt, and polyimide film formation. The object is to provide a film-forming improver that suppresses the aging of a composition for use.

The present inventors have found that a composition containing a salt of a carboxylic acid anion having a specific structure containing an alicyclic group and a nitrogen-containing heterocyclic cation is excellent in film-forming properties and stability over time. Arrived.

（上記式中、Ａは、１又は２以上の脂環基を含み、上記式中のｎ個の－ＣＯＯ^－Ｍ^＋及び（４－ｎ）個の－ＣＯＯＨがそれぞれ独立して上記１又は２以上の脂環基に直接又は連結基を介して結合している４価の有機基を表し、Ｍ^＋は、含窒素複素環を含むカチオンを表し、ｎは１以上４以下の整数を表す。） A first aspect of the present invention is
A composition containing a salt represented by the following formula (1).

(In the above formula, A contains 1 or 2 or more alicyclic groups, and n -COO ^- M ⁺ and (4-n) -COOH in the above formula are each independently the above 1 or 2 represents a tetravalent organic group bonded directly or via a linking group to the above alicyclic groups, M ⁺ represents a cation containing a nitrogen-containing heterocycle, and n represents an integer of 1 or more and 4 or less. )

（上記式中、Ａは、１又は２以上の脂環基を含み、上記式中のｎ個の－ＣＯＯ^－Ｍ^＋及び（４－ｎ）個の－ＣＯＯＨがそれぞれ独立して上記１又は２以上の脂環基に直接又は連結基を介して結合している４価の有機基を表し、Ｍ^＋は、含窒素複素環を含むカチオンを表し、ｎは１以上４以下の整数を表す。） A second aspect of the present invention is a cured product of the composition of the first aspect.
A third aspect of the invention comprises applying the composition of the first aspect to form a film, and
A method for producing a cured product, comprising heating the film.
A fourth aspect of the present invention is a salt represented by the following general formula (1).

(In the above formula, A contains 1 or 2 or more alicyclic groups, and n -COO ^- M ⁺ and (4-n) -COOH in the above formula are each independently the above 1 or 2 represents a tetravalent organic group bonded directly or via a linking group to the above alicyclic groups, M ⁺ represents a cation containing a nitrogen-containing heterocycle, and n represents an integer of 1 or more and 4 or less. )

A fifth aspect of the present invention is an agent for suppressing deterioration over time and improving film-forming properties of a polyimide film-forming composition, comprising the salt of the fourth aspect.

According to the present invention, a composition excellent in film-forming properties and stability over time, a cured product of the composition, a method for producing a cured product using the composition, a salt, and suppression of changes over time in a composition for forming a polyimide film And a film-forming improver can be provided.

Embodiments of the present invention will be described in detail below, but the present invention is by no means limited to the following embodiments, and can be carried out with appropriate modifications within the scope of the object of the present invention. .
In addition, in this specification, unless otherwise specified, "-" represents from the above to the following.

≪Composition≫
The composition according to the first aspect contains a salt represented by the general formula (1).
The above salt can contribute to film formability and stability over time.
The present invention also relates to a salt represented by the above general formula (1), a polyimide film-forming composition for suppressing changes over time and a film-forming property improving agent, and the invention according to a fourth aspect is the above general formula ( 1), and a fifth aspect of the invention is an agent for suppressing aging and improving film-forming properties of a composition for forming a polyimide film, comprising the salt of the fourth aspect.

<Salt>
(anion portion)
In the above formula (1), A contains one or more alicyclic groups, and n -COO ^- M ⁺ and (4-n) -COOH in the above formula are each independently the above 1 or represents a tetravalent organic group bonded directly or via a linking group to two or more alicyclic groups.
From the viewpoint of achieving the effects of the present invention more reliably, n is preferably 2 or more and 4 or less, more preferably 2 or 3.
The linking group includes an alkylene group, an alkyleneoxy group, a cycloalkylene group, or a cycloalkyleneoxy group, preferably an alkylene group or an alkyleneoxy group, and more preferably an alkylene group.
The alkylene moiety in the alkylene group and the alkyleneoxy group has 1 to 5 carbon atoms which may have a substituent (preferably 1 to 3 carbon atoms, more preferably 1 or 2 carbon atoms). ) alkylene group. Specific examples of the alkylene group include methylene group, ethylene group, propylene group, butylene group, pentylene group and the like, preferably methylene group, ethylene group or propylene group, more preferably methylene group or ethylene group.
Examples of the cycloalkylene moiety in the cycloalkylene group and the cycloalkyleneoxy group include a cyclopentylene group and a cyclohexylene group.
In the above formula, n -COO ^- M ⁺ and (4-n) -COOH are preferably directly bonded to one or more alicyclic groups.
The tetravalent organic group A has 4 to 40 carbon atoms (preferably 5 to 30 carbon atoms, more preferably 6 to 25 carbon atoms, still more preferably 6 to 20 carbon atoms). Examples include tetravalent organic groups, which may or may not contain an aromatic group (e.g., a benzene ring group, a naphthalene ring group, etc.) other than the one or more alicyclic groups described above, but may or may not contain an aromatic group. preferably not.
In A, one or more alicyclic groups and the above aromatic groups may or may not be condensed.
One or more alicyclic groups may or may not be linked by a spiro bond.
The tetravalent organic group A has a hetero atom (e.g., oxygen atom, sulfur atom, nitrogen atom), keto group (-CO-) or unsaturated bond (e.g., carbon-carbon double bond, carbon-carbon triple bond) may or may not be included.
The tetravalent organic group A may or may not have a substituent,

The alicyclic group contained in the tetravalent organic group A may be monocyclic or polycyclic, and has 3 to 20 carbon atoms (preferably 4 to 15 carbon atoms, more preferably 5 or more and 12 or less carbon atoms, more preferably 6 or more and 10 or less carbon atoms), and monocyclic or polycyclic alicyclic groups having 3 or more and 20 or less membered rings. group, more preferably a 4- to 18-membered monocyclic or polycyclic alicyclic group, more preferably a 5- to 14-membered monocyclic or polycyclic alicyclic group, and a 6-membered A monocyclic or polycyclic alicyclic group having a ring or more and 10 or less members is particularly preferred.
The number of alicyclic groups contained in the organic group A is preferably 1 or more and 6 or less, more preferably 1 or more and 5 or less.
The alicyclic group may or may not contain a bridging group that bridges the ring, and the bridging group has 1 to 5 carbon atoms (preferably 1 to 3 carbon atoms, more preferably includes a divalent group having 1 or 2) carbon atoms.
Specific examples of alicyclic groups containing a bridging group include groups containing a bicyclo[2.2.1]heptane structure and the like.
The bridging group is preferably an alkylene group, an ether bond (-O-), a thioether bond (-S-), a keto group or a divalent group in which at least two of them are combined, and an alkylene group, an ether bond and a thioether. A bond or a divalent group combining at least two of them is more preferred, an alkylene group, an ether bond, a thioether bond or a divalent group combining at least two of them is even more preferred, an alkylene group, an ether bond or a thioether A bond is particularly preferred, and an alkylene group is most preferred.

Examples of the alkylene group include alkylene groups having 1 to 5 carbon atoms (preferably 1 to 3 carbon atoms, more preferably 1 or 2 carbon atoms) which may have a substituent. Specific examples of the alkylene group include methylene group, ethylene group, propylene group, butylene group, pentylene group and the like, preferably methylene group, ethylene group or propylene group, more preferably methylene group or ethylene group.

The alicyclic group contains a heteroatom (e.g., oxygen atom, sulfur atom, nitrogen atom), a keto group, or an unsaturated bond (e.g., carbon-carbon double bond, carbon-carbon triple bond) as a ring-constituting atom. May or may not be present.
The alicyclic group may or may not have a substituent.

A halogen atom or an organic group is mentioned as a substituent which the tetravalent organic group A, the said alicyclic group, or the said alkylene group may have.
Halogen atoms include fluorine, chlorine, bromine and iodine atoms.
Organic groups as substituents include organic groups having 1 to 10 carbon atoms. Suitable examples of organic groups include alkyl groups and alkoxy groups.
Examples of the alkyl group include alkyl groups having 1 to 10 carbon atoms. Specific examples of alkyl groups include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, pentyl, hexyl, heptyl, octyl and nonyl groups. , a decyl group, etc., and an alkyl group having 1 to 4 carbon atoms is preferable.
The alkyl group may have a substituent. When the alkyl group has a substituent, examples of the substituent include a halogen atom and an alkoxy group.

The alkoxy group includes an alkoxy group having 1 or more and 10 or less carbon atoms. Specific examples of the alkoxy group include methoxy group, ethoxy group, propoxy group, butoxy group, hexyloxy group, octyloxy group and the like, and an alkoxy group having 1 to 4 carbon atoms is preferred.
The alkoxy group may have a substituent. When the alkoxy group has a substituent, examples of the substituent include a halogen atom and an alkoxy group.

（上記式（ａ２）中、Ｒ^ａ１１、Ｒ^ａ１２、及びＲ^ａ１３は、それぞれ独立に、水素原子、炭素原子数１以上５以下のアルキル基及びフッ素原子からなる群より選択される１種であり、ｍは０以上１２以下の整数である。）
なお、式（ａ２）中のｍは、原料化合物の精製が容易である点から、ｍは５以下が好ましく、３以下がより好ましい。また、化学的安定性の観点から、ｍは１以上が好ましく、２以上がより好ましい。
式（ａ２）中のｍは、２又は３が特に好ましい。 The tetravalent organic group A may or may not be a residue obtained by removing two acid anhydride groups from the tetracarboxylic dianhydride, and n -COO ^- M in the above formula (1) It may or may not be a tetravalent organic group containing two identical or different alicyclic groups to which two selected from the group consisting of ⁺ and (4-n) -COOH are bonded.
One preferred embodiment of the tetravalent organic group A is a tetravalent group represented by the following formula (a2).

(In formula (a2) above, R ^a11 , R ^a12 , and R ^a13 are each independently one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, and a fluorine atom. , m is an integer from 0 to 12.)
Note that m in the formula (a2) is preferably 5 or less, more preferably 3 or less, from the viewpoint of facilitating purification of the raw material compound. From the viewpoint of chemical stability, m is preferably 1 or more, more preferably 2 or more.
2 or 3 is particularly preferable for m in the formula (a2).

Specific examples of the tetravalent organic group A are shown below, but the present invention is not limited thereto. In the following formula, * indicates a bond that directly bonds to -COO ^- M ⁺ or -COOH or bonds to a linking group that bonds to -COO ^- M ⁺ or -COOH.

(cation part)
The cation M ⁺ containing the nitrogen-containing heterocycle (M) in the above formula (1) contains 1 or more (preferably 1 or more and 5 or less, more preferably 2 or more and 4 or less, still more preferably 2 or 3) nitrogen atoms. Examples include cations containing a nitrogen-containing heterocyclic ring having 2 to 30 carbon atoms (preferably 2 to 20, more preferably 3 to 15, still more preferably 3 to 10), aromatic or non-aromatic any cation containing a nitrogen-containing heterocyclic ring, preferably a cation containing an aromatic nitrogen-containing heterocyclic ring.
The cation M ⁺ containing a nitrogen-containing heterocycle (M) may or may not contain a heteroatom other than a nitrogen atom (e.g., an oxygen atom, a sulfur atom, etc.) as an atom constituting the ring, and has a substituent. may or may not be present.

（式（２）中、Ｒ^１１はそれぞれ独立に水素原子又は有機基を表し、ｓは２以上６以下の整数を表す。）
Ｒ^１１についての有機基としては、アルキル基、シクロアルキル基、アラルキル基、及びアリール基等が挙げられる。上記アルキル基、上記シクロアルキル基、上記アラルキル基、及び上記アリール基は、置換基を有していてもよい。上記置換基としては、フッ素原子、塩素原子、臭素原子、及びヨウ素原子等のハロゲン原子；シアノ基；ニトロ基；メトキシ基、エトキシ基、及びｔｅｒｔ－ブトキシ基等のアルコキシ基；フェノキシ基、及びｐ－トリルオキシ基等のアリールオキシ基；アセトキシ基、プロピオニルオキシ基、及びベンゾイルオキシ基等のアシルオキシ基；メトキシカルボニル基、及びブトキシカルボニル基等のアルコキシカルボニル基；フェノキシカルボニル基等のアリールオキシカルボニル基；ビニルオキシカルボニル基、及びアリルオキシカルボニル基等のアルケニルオキシカルボニル基；アセチル基、ベンゾイル基、イソブチリル基、アクリロイル基、メタクリロイル基、及びメトキサリル基等のアシル基；メチルスルファニル基、及びｔｅｒｔ－ブチルスルファニル基等のアルキルスルファニル基；フェニルスルファニル基、及びｐ－トリルスルファニル基等のアリールスルファニル基；メチルアミノ基、及びシクロヘキシルアミノ基等の脂肪族第二級アミノ基；ジメチルアミノ基、ジエチルアミノ基、モルホリノ基、及びピペリジノ基等の脂肪族第三級アミノ基；フェニルアミノ基、ｐ－トリルアミノ基等の芳香族第二級アミノ基；メチル基、エチル基、ｔｅｒｔ－ブチル基、及びドデシル基等のアルキル基；フェニル基、ｐ－トリル基、キシリル基、クメニル基、ナフチル基、アンスリル基、フェナントリル基等のアリール基；ヒドロキシ基；カルボキシ基；スルホンアミド基；ホルミル基；メルカプト基；スルホ基；メシル基；ｐ－トルエンスルホニル基；第一級アミノ基；ニトロソ基；トリフルオロメチル基、及びトリクロロメチル基等のハロゲン化アルキル基；トリメチルシリル基；ホスフィニコ基；ホスホノ基；アルキルスルホニル基；アリールスルホニル基；トリアルキルアンモニウム基；ジメチルスルホニウミル基；トリフェニルフェナシルホスホニウミル基等が挙げられる。
ｓは３以上５以下の整数であることが好ましく、３又は４であることがより好ましい。

（式中、Ｒ^Ｈは、それぞれ独立に水素原子又はアルキル基を表す。Ｒ^２１、Ｒ^２３、Ｒ^２５、Ｒ^２６、Ｒ^２７、Ｒ^２８、Ｒ^３０、Ｒ^３１、及びＲ^３２はそれぞれ独立に水素原子、ハロゲン原子、シアノ基、ニトロ基、アルキル基、シクロアルキル基、アルケニル基、又はアルキニル基を表す。Ｒ^２２、Ｒ^２４、及びＲ^２９はそれぞれ独立に水素原子、ハロゲン原子、アルキル基、シクロアルキル基、アルケニル基、又はアルキニル基を表す。Ｒ^２１～Ｒ^３２はそれぞれ独立にハロゲン原子、シアノ基、又はニトロ基で置換されていてもよい。
Ｒ^２１及びＲ^２２は互いに結合して環を形成していてもよい。少なくとも２つのＲ^２１は互いに結合して環を形成していてもよい。Ｒ^２３、及びＲ^２４は互いに結合して環を形成していてもよい。２つのＲ^２３は互いに結合して環を形成していてもよい。少なくとも２つのＲ^２５は互いに結合して環を形成していてもよい。少なくとも２つのＲ^２６は互いに結合して環を形成していてもよい。少なくとも２つのＲ^２７は互いに結合して環を形成していてもよい。Ｒ^２８、及びＲ^２９は互いに結合して環を形成していてもよい。少なくとも２つのＲ^２８は互いに結合して環を形成していてもよい。少なくとも２つのＲ^３０は互いに結合して環を形成していてもよい。少なくとも２つのＲ^３１は互いに結合して環を形成していてもよい。少なくとも２つのＲ^３２は互いに結合して環を形成していてもよい。） From the viewpoint of more reliably achieving the effects of the present invention, the cation M 1 ⁺ containing the nitrogen-containing heterocycle (M) is preferably a cation represented by any one of the following formulas (2) to (11).

(In formula (2), each R ¹¹ independently represents a hydrogen atom or an organic group, and s represents an integer of 2 or more and 6 or less.)
Organic groups for R ¹¹ include alkyl groups, cycloalkyl groups, aralkyl groups, aryl groups, and the like. The alkyl group, the cycloalkyl group, the aralkyl group, and the aryl group may have a substituent. Examples of the substituents include fluorine, chlorine, bromine, and iodine atoms; cyano; nitro; methoxy, ethoxy, and tert-butoxy; alkoxy; phenoxy, and p - aryloxy groups such as tolyloxy; acyloxy groups such as acetoxy, propionyloxy, and benzoyloxy; alkoxycarbonyl groups such as methoxycarbonyl and butoxycarbonyl; aryloxycarbonyl groups such as phenoxycarbonyl; alkenyloxycarbonyl groups such as an oxycarbonyl group and an allyloxycarbonyl group; acyl groups such as an acetyl group, a benzoyl group, an isobutyryl group, an acryloyl group, a methacryloyl group, and a methoxalyl group; a methylsulfanyl group and a tert-butylsulfanyl group; arylsulfanyl groups such as phenylsulfanyl group and p-tolylsulfanyl group; aliphatic secondary amino groups such as methylamino group and cyclohexylamino group; dimethylamino group, diethylamino group, morpholino group, and Aliphatic tertiary amino groups such as piperidino group; Aromatic secondary amino groups such as phenylamino group and p-tolylamino group; Alkyl groups such as methyl group, ethyl group, tert-butyl group, and dodecyl group; Phenyl group, p-tolyl group, xylyl group, cumenyl group, naphthyl group, anthryl group, aryl group such as phenanthryl group; hydroxy group; carboxy group; sulfonamide group; formyl group; mercapto group; sulfo group; toluenesulfonyl group; primary amino group; nitroso group; halogenated alkyl group such as trifluoromethyl group and trichloromethyl group; trimethylsilyl group; phosphinico group; a dimethylsulfoniumyl group; a triphenylphenacylphosphoniumyl group; and the like.
s is preferably an integer of 3 or more and 5 or less, more preferably 3 or 4.

(In the formula, ^RH each independently represents a hydrogen ^atom or an alkyl group. R ²¹ , R ²³ , R ²⁵ , R ²⁶ , R 27 , R ²⁸ , R ³⁰ , R ³¹ and R ³² each independently represents a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group, a cycloalkyl group, an alkenyl group, or an alkynyl group, wherein R ²² , R ²⁴ and R ²⁹ each independently represent a hydrogen atom, a halogen atom, an alkyl group, represents a cycloalkyl group, an alkenyl group, or an alkynyl group, and each of R ²¹ to R ³² may be independently substituted with a halogen atom, a cyano group, or a nitro group;
R ²¹ and R ²² may combine with each other to form a ring. At least two R ²¹ may combine with each other to form a ring. R ²³ and R ²⁴ may combine with each other to form a ring. Two R ²³ may combine with each other to form a ring. At least two R ²⁵ may combine with each other to form a ring. At least two R ²⁶ may combine with each other to form a ring. At least two R ²⁷ may be bonded together to form a ring. R ²⁸ and R ²⁹ may combine with each other to form a ring. At least two R ²⁸ may be bonded together to form a ring. At least two R ³⁰ may be bonded together to form a ring. At least two R ³¹ may be bonded together to form a ring. At least two R ³² may be bonded together to form a ring. )

Halogen atoms for R ²¹ to R ³² include fluorine, chlorine, bromine, or iodine atoms.
The alkyl group for R ^H and R ²¹ to R ³² may be a straight-chain alkyl group or a branched-chain alkyl group. The number of carbon atoms in the alkyl group is not particularly limited. The number of carbon atoms in the alkyl group is preferably 1 or more and 20 or less, more preferably 1 or more and 10 or less, and particularly preferably 1 or more and 5 or less.
Specific examples of alkyl groups for R ^H and R ²¹ to R ³² include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, sec-butyl group and tert-butyl group. , n-pentyl group, isopentyl group, tert-pentyl group, n-hexyl group, n-heptyl group, n-octyl group, 2-ethyl-n-hexyl group, n-nonyl group, n-decyl group, n- undecyl group, n-dodecyl group, n-tridecyl group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-heptadecyl group, n-octadecyl group, n-nonadecyl group, and n-icosyl group. be done.

The cycloalkyl group for R ²¹ to R ³² is preferably a cycloalkyl group having 5 or more and 30 or less carbon atoms. Specific examples of cycloalkyl groups include a cyclopentyl group and a cyclohexyl group.
The alkenyl group for R ²¹ to R ³² is preferably an alkenyl group having 2 or more and 10 or less carbon atoms. Specific examples of alkenyl groups include vinyl groups, allyl groups, and styryl groups.
The alkynyl group for R ²¹ to R ³² is preferably an alkynyl group having 2 or more and 10 or less carbon atoms. Specific examples of alkynyl groups include ethynyl, propynyl, and propargyl groups.

In the composition according to the first aspect, the salt may be contained singly or in combination of two or more.
The salt is a tetracarboxylic acid compound in which four —COOH are bonded directly or via a linking group to the tetravalent organic group A in the formula (1), and the nitrogen-containing heterocyclic compound (M). can be produced by mixing and reacting (for example, neutralization reaction) under arbitrary conditions.

The content of the salt represented by the above formula (1) in the composition according to the first aspect is not particularly limited, but is 0.01% by mass or more with respect to the entire composition according to the first aspect. It is preferably 80% by mass or less, more preferably 0.1% by mass or more and 50% by mass or less, even more preferably 0.5% by mass or more and 30% by mass or less, and 1% by mass or more and 15% by mass. % or less is particularly preferred. Further, it is preferably 0.1% by mass or more and 80% by mass or less, and preferably 0.5% by mass or more and 70% by mass or less, relative to the entire composition (excluding the solvent) according to the first aspect. More preferably, it is 1% by mass or more and 60% by mass or less.
In addition, the ratio of the mass of the salt to the mass of at least one resin precursor or resin selected from the group consisting of a monomer component consisting of the following diamine component and a tetracarboxylic dianhydride component, polyamic acid and polyimide is 1 mass. % or more and 50 mass % or less, more preferably 5 mass % or more and 30 mass % or less, and more preferably 7 mass % or more and 20 mass % or less.

（式（ｄ１）中、Ｄは炭素原子数６以上５０以下の４価の有機基であり、Ｂは２価の有機基である。） <At least one resin precursor or resin selected from the group consisting of a monomer component consisting of a diamine component and a tetracarboxylic dianhydride component, a polyamic acid, and a polyimide>
The composition according to the first aspect is selected from the group consisting of a monomer component consisting of a diamine compound and a tetracarboxylic dianhydride, a polyamic acid (D), and a polyimide, from the viewpoint of achieving the effects of the present invention more reliably. It is preferable to further contain at least one resin precursor or resin, and it is more preferable to further contain polyamic acid (D).
Polyamic acid (D) is a polyimide resin precursor that is produced when the composition is cured. Polyamic acid (D) can usually be obtained by condensing a monomer component consisting of a tetracarboxylic dianhydride and a diamine compound.
A polyamic acid may have a structural unit represented by the following formula (d1).

(In formula (d1), D is a tetravalent organic group having 6 to 50 carbon atoms, and B is a divalent organic group.)

The tetracarboxylic dianhydride, the diamine compound, and the method for producing the polyamic acid (D), which are used in the production of the polyamic acid (D), are described below.

（式（ｄ１－１）中、Ｄは炭素原子数６以上５０以下の４価の有機基である。） [Tetracarboxylic dianhydride]
A tetracarboxylic dianhydride that produces a structural unit represented by formula (d1) is represented by the following formula (d1-1).
A tetracarboxylic dianhydride represented by the formula (d1-1) reacts with a diamine compound described later to give a polyamic acid (D) having a structural unit represented by the formula (d1). Such tetracarboxylic dianhydrides may be used singly or in combination of two or more.

(In formula (d1-1), D is a tetravalent organic group having 6 to 50 carbon atoms.)

In formula (d1-1), D is a tetravalent organic group having 6 to 50 carbon atoms, and an acid anhydride represented by two -CO-O-CO- in formula (d1-1) In addition to the physical group, it may have one or more substituents.
Preferable examples of the substituent include a fluorine atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and the number of carbon atoms. A fluorinated alkoxy group of 1 to 6 is preferred, and may contain a carboxy group and a carboxylate group in addition to the acid anhydride group represented by formula (d1-1).
When the substituent is a fluorinated alkyl group or fluorinated alkoxy group, it is preferably a perfluoroalkyl group or perfluoroalkoxy group.
The same applies to the substituents described above and one or more substituents that the aromatic group described later may have on the aromatic ring.

In formula (d1-1), D is a tetravalent organic group with a lower limit of 6 carbon atoms and an upper limit of 50 carbon atoms.
The number of carbon atoms constituting D is more preferably 8 or more, still more preferably 12 or more. Moreover, the number of carbon atoms constituting D is more preferably 40 or less, and still more preferably 30. D may be an aliphatic group, an aromatic group, or a group combining these structures. D may contain a halogen atom, an oxygen atom and a sulfur atom in addition to a carbon atom and a hydrogen atom. When D contains an oxygen atom, a nitrogen atom, or a sulfur atom, the oxygen atom, the nitrogen atom, or the sulfur atom is a nitrogen-containing heterocyclic group, -CONH-, -NH-, -N=N-, -CH=N -, -COO-, -O-, -CO-, -SO-, -SO ₂ -, -S-, and -S-S- may be included in D as a group selected from -O D is more preferably included as a group selected from -, -CO-, -SO-, -SO ₂ -, -S- and -S-S-.

The tetracarboxylic dianhydride can be appropriately selected from tetracarboxylic dianhydrides conventionally used as raw materials for synthesizing polyamic acids. The tetracarboxylic dianhydride may be either an aliphatic tetracarboxylic dianhydride or an aromatic tetracarboxylic dianhydride.

Examples of aliphatic tetracarboxylic dianhydrides include 2,2-bis(3,4-dicarboxy)propane dianhydride and bis(3,4-dicarboxy)methane dianhydride. Moreover, the aliphatic tetracarboxylic dianhydride may contain an alicyclic structure. The alicyclic structure may be polycyclic. Examples of polycyclic alicyclic structures include bridged alicyclic structures such as bicyclo[2.2.1]heptane. For example, a bridged alicyclic structure may be fused with another bridged alicyclic structure and/or a non-bridged alicyclic structure, or a bridged alicyclic structure may It may be connected to the formula structure and/or the non-bridged alicyclic structure by a spiro bond. When an aliphatic tetracarboxylic dianhydride is used, there is a tendency to easily obtain a cured product having excellent transparency using the composition.

（式（ｄ２）中、Ｒ^ｄ１１、Ｒ^ｄ１２、及びＲ^ｄ１３は、それぞれ独立に、水素原子、炭素原子数１以上５以下のアルキル基及びフッ素原子からなる群より選択される１種であり、ｄは０以上１２以下の整数である。） As the aliphatic group constituting D in formula (d1-1), for example, a tetravalent group represented by formula (d2) below can be employed. When such a group is used, there is a tendency to easily obtain a transparent polyimide film.
Note that d in the formula (d2) is preferably 5 or less, more preferably 3 or less, from the viewpoint of facilitating purification of the raw material compound. Further, d is preferably 1 or more, more preferably 2 or more, because the chemical stability of the raw material compound that provides the structural unit represented by formula (d1) is excellent.
2 or 3 is particularly preferable for d in the formula (d2).

(in formula (d2), R ^d11 , R ^d12 and R ^d13 are each independently one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 5 carbon atoms and a fluorine atom; d is an integer from 0 to 12.)

Examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride, 3,3′,4,4′-oxy bisphthalic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,3,3′,4′-biphenyltetracarboxylic dianhydride, 3,3′,4, 4'-benzophenonetetracarboxylic dianhydride, 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride and the like.

The aromatic tetracarboxylic dianhydride may also be, for example, compounds represented by the following general formulas (d1-2) to (d1-4).

In the above formulas (d1-2) and (d1-3), R ^d1 , R ^d2 and R ^d3 are each an optionally halogen-substituted aliphatic group, an oxygen atom, a sulfur atom, one or more 2 A divalent group that is either an aromatic group via a valence element or is composed of a combination thereof. R ^d2 and R ^d3 may be the same or different.
That is, R ^d1 , R ^d2 and R ^d3 may contain a carbon-carbon single bond, a carbon-oxygen-carbon ether bond or a halogen element (fluorine, chlorine, bromine, iodine), 2,2- bis(3,4-dicarboxyphenoxy)propane dianhydride, 1,4-bis(3,4-dicarboxyphenoxy)benzene dianhydride and the like.

In the above formula (d1-4), R ^d4 and R ^d5 are either an aliphatic group optionally substituted with halogen, an aromatic group via one or more divalent elements, or halogen. , or a monovalent substituent constituted by a combination thereof, which may be the same or different, and difluoropyromellitic dianhydride, dichloropyromellitic dianhydride, etc. can also be used. .

Examples of tetracarboxylic dianhydrides for obtaining fluorine-containing polyimides containing fluorine in the molecular structure include (trifluoromethyl)pyromellitic dianhydride and di(trifluoromethyl)pyromellitic dianhydride. , di(heptafluoropropyl)pyromellitic dianhydride, pentafluoroethylpyromellitic dianhydride, bis{3,5-di(trifluoromethyl)phenoxy}pyromellitic dianhydride, 2,2-bis (3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 5,5′-bis(trifluoromethyl)-3,3′,4,4′-tetracarboxybiphenyl dianhydride, 2,2′, 5,5′-tetrakis(trifluoromethyl)-3,3′,4,4′-tetracarboxybiphenyl dianhydride, 5,5′-bis(trifluoromethyl)-3,3′,4,4′ -tetracarboxydiphenyl ether dianhydride, 5,5′-bis(trifluoromethyl)-3,3′,4,4′-tetracarboxybenzophenone dianhydride, bis{(trifluoromethyl)dicarboxyphenoxy}benzene di anhydride, bis{(trifluoromethyl)dicarboxyphenoxy}(trifluoromethyl)benzene dianhydride, bis(dicarboxyphenoxy)(trifluoromethyl)benzene dianhydride, bis(dicarboxyphenoxy)bis(trifluoro methyl)benzene dianhydride, bis(dicarboxyphenoxy)tetrakis(trifluoromethyl)benzene dianhydride, 2,2-bis{4-(3,4-dicarboxyphenoxy)phenyl}hexafluoropropane dianhydride, Bis{(trifluoromethyl)dicarboxyphenoxy}biphenyl dianhydride, bis{(trifluoromethyl)dicarboxyphenoxy}bis(trifluoromethyl)biphenyl dianhydride, bis{(trifluoromethyl)dicarboxyphenoxy}diphenyl ether dianhydride, bis(dicarboxyphenoxy)bis(trifluoromethyl)biphenyl dianhydride, difluoropyromellitic dianhydride, 1,4-bis(3,4-dicarboxytrifluorophenoxy)tetrafluorobenzene dianhydride and 1,4-bis(3,4-dicarboxytrifluorophenoxy)octafluorobiphenyl dianhydride.

As the tetracarboxylic dianhydride, considering the heat resistance, tensile elongation, chemical resistance, etc. of the resulting film or molded article, it is preferable to use an aromatic tetracarboxylic dianhydride, which is easy to obtain and inexpensive. 3,3′,4,4′-Biphenyltetracarboxylic dianhydride and pyromellitic dianhydride are preferably used in view of their properties and the like.
Incidentally, tetracarboxylic acid acid chlorides, esterified products, etc. having the same basic skeleton as these can also be used.

In this embodiment, the tetracarboxylic dianhydride may be used in combination with the dicarboxylic anhydride. When these carboxylic acid anhydrides are used in combination, the properties of the obtained imide ring-containing polymer such as polyimide resin may be further improved. Examples of dicarboxylic anhydrides include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, chlorendic anhydride, methyltetrahydrophthalic anhydride, phthalic anhydride, glutaric anhydride, cis-4-cyclohexene-1,2-dicarboxylic anhydride and the like.

[Diamine compound]
A compound represented by the following formula (d3-1) can typically be used as the diamine compound. A diamine compound may be used individually by 1 type, and may be used in combination of 2 or more type.
H ₂ NB-NH ₂ (d3-1)
(In formula (d3-1), B represents a divalent organic group.)

In formula (d3-1), B is a divalent organic group, which may have one or more substituents in addition to the two amino groups in formula (d3-1).
Preferable examples of the substituent include a fluorine atom, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and the number of carbon atoms. 1 to 6 fluorinated alkoxy groups or hydroxyl groups are preferred.
When the substituent is a fluorinated alkyl group or fluorinated alkoxy group, it is preferably a perfluoroalkyl group or perfluoroalkoxy group.

In formula (d3-1), the lower limit of the number of carbon atoms in the organic group as B is preferably 2, more preferably 6, and the upper limit is preferably 50, more preferably 30.
B may be an aliphatic group, but is preferably an organic group containing one or more aromatic rings.

When B is an organic group containing one or more aromatic rings, the organic group may be one aromatic group itself, and the two or more aromatic groups are aliphatic hydrocarbon groups and halogenated aliphatic It may be a hydrocarbon group or a group bonded via a bond containing a heteroatom such as an oxygen atom, a sulfur atom, or a nitrogen atom. Bonds containing heteroatoms such as oxygen atoms, sulfur atoms, and nitrogen atoms contained in B include -CONH-, -NH-, -N=N-, -CH=N-, -COO-, -O -, -CO-, -SO-, -SO ₂ -, -S-, and -S-S-, and -O-, -CO-, -SO-, -SO ₂ -, -S- , and -SS- are preferred.

The aromatic ring bonded to the amino group in B is preferably a benzene ring. When the ring bonded to the amino group in B is a condensed ring containing two or more rings, the ring bonded to the amino group in the condensed ring is preferably a benzene ring.
Moreover, the aromatic ring contained in B may be an aromatic heterocyclic ring.

（式（２１）～（２４）中、Ｒ^１１１は、水素原子、フッ素原子、水酸基、炭素原子数１以上４以下のアルキル基、及び炭素原子数１以上４以下のハロゲン化アルキル基よりなる群から選択される１種を示す。式（２４）中、Ｑは、９，９’－フルオレニリデン基、又は、式：－Ｃ_６Ｈ_４－、－ＣＯＮＨ－Ｃ_６Ｈ_４－ＮＨＣＯ－、－ＮＨＣＯ－Ｃ_６Ｈ_４－ＣＯＮＨ－、－Ｏ－Ｃ_６Ｈ_４－ＣＯ－Ｃ_６Ｈ_４－Ｏ－、－ＯＣＯ－Ｃ_６Ｈ_４－ＣＯＯ－、－ＯＣＯ－Ｃ_６Ｈ_４－Ｃ_６Ｈ_４－ＣＯＯ－、－ＯＣＯ－、－Ｏ－、－Ｓ－、－ＣＯ－、－ＣＯＮＨ－、－ＳＯ_２－、－Ｃ（ＣＦ_３）_２－、－Ｃ（ＣＨ_３）_２－、－ＣＨ_２－、－Ｏ－Ｃ_６Ｈ_４－Ｃ（ＣＨ_３）_２－Ｃ_６Ｈ_４－Ｏ－、－Ｏ－Ｃ_６Ｈ_４－Ｃ（ＣＦ_３）_２－Ｃ_６Ｈ_４－Ｏ－、－Ｏ－Ｃ_６Ｈ_４－ＳＯ_２－Ｃ_６Ｈ_４－Ｏ－、－Ｃ（ＣＨ_３）_２－Ｃ_６Ｈ_４－Ｃ（ＣＨ_３）_２－、－Ｏ－Ｃ_１０Ｈ_６－Ｏ－、－Ｏ－Ｃ_６Ｈ_４－Ｃ_６Ｈ_４－Ｏ－、及び－Ｏ－Ｃ_６Ｈ_４－Ｏ－で表される基よりなる群から選択される１種を示す。
Ｑの例示における、－Ｃ_６Ｈ_４－はフェニレン基であり、ｍ－フェニレン基、及びｐ－フェニレン基が好ましく、ｐ－フェニレン基がより好ましい。また、－Ｃ_１０Ｈ_６－は、ナフタレンジイル基であり、ナフタレン－１，２－ジイル基、ナフタレン－１，４－ジイル基、ナフタレン－２，３－ジイル基、ナフタレン－２，６－ジイル基、及びナフタレン－２，７－ジイル基が好ましく、ナフタレン－１，４－ジイル基、及びナフタレン－２，６－ジイル基がより好ましい。） When B is an organic group containing an aromatic ring, the organic group is a group represented by the following formulas (21) to (24) from the viewpoint of heat resistance of the cured product formed using the resin composition. At least one of them is preferred.

(In formulas (21) to (24), R ¹¹¹ is a group consisting of a hydrogen atom, a fluorine atom, a hydroxyl group, an alkyl group having 1 to 4 carbon atoms, and a halogenated alkyl group having 1 to 4 carbon atoms. wherein Q is a 9,9′-fluorenylidene group or a formula: —C ₆ H ₄ —, —CONH—C ₆ H ₄ —NHCO—, —NHCO _{-C6H4 -} CONH- _, -O- _C6H4 -CO _- C6H4 _{- O-} , -OCO- _{C6H4 -} COO-, -OCO- _{C6H4 - C6H4} -COO-, -OCO-, -O-, -S-, -CO-, -CONH-, _-SO2- , -C( _CF3 ) _2- , -C( _CH3 ) _2- , _-CH2 -, -OC ₆ H ₄ -C(CH ₃ ) ₂ -C ₆ H ₄ -O-, -OC ₆ H ₄ -C(CF ₃ ) ₂ -C ₆ H ₄ -O-, -O —C ₆ H ₄ —SO ₂ —C ₆ H ₄ —O—, —C(CH ₃ ) ₂ —C ₆ H ₄ —C(CH ₃ ) ₂ —, —O—C ₁₀ H ₆ —O—, — One selected from the group consisting of groups represented by OC ₆ H ₄ -C ₆ H ₄ -O- and -OC ₆ H ₄ -O-.
—C ₆ H ₄ — in the examples of Q is a phenylene group, preferably an m-phenylene group and a p-phenylene group, more preferably a p-phenylene group. -C ₁₀ H ₆ - is a naphthalene diyl group, naphthalene-1,2-diyl group, naphthalene-1,4-diyl group, naphthalene-2,3-diyl group, naphthalene-2,6-diyl and naphthalene-2,7-diyl groups are preferred, and naphthalene-1,4-diyl groups and naphthalene-2,6-diyl groups are more preferred. )

R ¹¹¹ in formulas (21) to (24) is more preferably a hydrogen atom, a hydroxyl group, a fluorine atom, a methyl group, an ethyl group, or a trifluoromethyl group from the viewpoint of the heat resistance of the cured product to be formed. A hydrogen atom, a hydroxyl group, or a trifluoromethyl group is particularly preferred.

Q in the formula (24) is a 9,9′-fluorenylidene group, —O—C ₆ H ₄ —O—, —C(CF ₃ ) ₂ —, from the viewpoint of heat resistance of the cured product to be formed. -O-, -C(CH ₃ ) ₂ -, -CH ₂ -, or -O-C ₆ H ₄ -C(CH ₃ ) ₂ -C ₆ H ₄ -O-, -CONH- is preferred, and -O —C ₆ H ₄ —O—, —C(CF ₃ ) ₂ — or —O— are particularly preferred.

When an aromatic diamine is used as the diamine compound represented by formula (d3-1), for example, aromatic diamines shown below can be preferably used.
That is, aromatic diamines include p-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, 4,4′-diaminobiphenyl, 4,4′-diamino-2,2′-bis(trifluoromethyl ) biphenyl, 3,3′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 4,4′-diaminodiphenyl sulfide, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 3,4′ -diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene , 4,4′-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]sulfone, 2,2-bis[4 -(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 9,9-bis(4-aminophenyl)fluorene, 9,9-bis( 4-amino-3-methylphenyl)fluorene, 4,4′-[1,4-phenylenebis(1-methylethane-1,1-diyl)]dianiline and the like. Among these, p-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, and 4,4'-diaminodiphenyl ether are preferred in terms of price, availability, and the like.

Moreover, as B, a silicon atom-containing group which may have a chain aliphatic group and/or an aromatic ring can be employed. As such a silicon atom-containing group, typically the groups shown below can be used.

（式（Ｓｉ－１）中、Ｒ^１１２及びＲ^１１３は、それぞれ独立に、単結合又はメチレン基、炭素原子数２以上２０以下のアルキレン基、炭素原子数３以上２０以下のシクロアルキレン基、又は炭素原子数６以上２０以下のアリーレン基等であり、Ｒ^１１４、Ｒ^１１５、Ｒ^１１６、及びＲ^１１７は、それぞれ独立に、炭素原子数１以上２０以下のアルキル基、炭素原子数３以上２０以下のシクロアルキル基、炭素原子数６以上２０以下のアリール基、炭素原子数２０以下のアミノ基を含む基、－Ｏ－Ｒ^１１８で表される基（Ｒ^１１８は炭素原子数１以上２０以下の炭化水素基）、炭素原子数２以上２０以下の１以上のエポキシ基を含む有機基であり、ｌは、３以上５０以下の整数である。） In addition, from the viewpoint of further improving the mechanical properties of the resulting cured product, as B, a group represented by the following formula (Si-1) can also be preferably used.

(In formula (Si-1), R ¹¹² and R ¹¹³ are each independently a single bond or a methylene group, an alkylene group having 2 to 20 carbon atoms, a cycloalkylene group having 3 to 20 carbon atoms, or an arylene group having 6 to 20 carbon atoms, etc., wherein R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ , and R ¹¹⁷ are each independently an alkyl group having 1 to 20 carbon atoms, and 3 to 20 carbon atoms; cycloalkyl group, an aryl group having 6 to 20 carbon atoms, a group containing an amino group having 20 or less carbon atoms, a group represented by —OR ¹¹⁸ (R ¹¹⁸ has 1 to 20 carbon atoms hydrocarbon group), an organic group containing one or more epoxy groups having 2 to 20 carbon atoms, and l is an integer of 3 to 50.)

The alkylene group having 2 to 20 carbon atoms in R ¹¹² and R ¹¹³ in formula (Si-1) is preferably an alkylene group having 2 to 10 carbon atoms from the viewpoint of heat resistance and residual stress, and dimethylene. group, trimethylene group, tetramethylene group, pentamethylene group, hexamethylene group and the like.

The cycloalkylene group having 3 to 20 carbon atoms in R ¹¹² and R ¹¹³ in formula (Si-1) is preferably a cycloalkylene group having 3 to 10 carbon atoms from the viewpoint of heat resistance and residual stress. , cyclobutylene group, cyclopentylene group, cyclohexylene group, cycloheptylene group and the like.
The arylene group having 6 to 20 carbon atoms in R ¹¹² and R ¹¹³ in formula (Si-1) is preferably an aromatic group having 6 to 20 carbon atoms from the viewpoint of heat resistance and residual stress. Examples include a phenylene group and a naphthylene group.

The alkyl group having 1 to 20 carbon atoms in R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ and R ¹¹⁷ in formula (Si-1) is an alkyl group having 1 to 10 carbon atoms from the viewpoint of heat resistance and residual stress. Alkyl groups are preferred, and specific examples include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, and hexyl groups.
The cycloalkyl group having 3 to 20 carbon atoms in R ¹¹³ , R ¹¹⁵ , R ¹¹⁶ and R ¹¹⁷ in formula (Si-1) has 3 to 10 carbon atoms from the viewpoint of heat resistance and residual stress. is preferred, and specific examples include a cyclopentyl group, a cyclohexyl group, and the like.
The aryl group having 6 to 20 carbon atoms in R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ and R ¹¹⁷ in formula (Si-1) is an aryl group having 6 to 12 carbon atoms from the viewpoint of heat resistance and residual stress. An aryl group is preferred, and specific examples include a phenyl group, a tolyl group, a naphthyl group and the like.
Examples of amino group-containing groups having 20 or less carbon atoms for R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ and R ¹¹⁷ in formula (Si-1) include amino groups and substituted amino groups (eg, bis(trialkylsilyl ) amino group) and the like.
The groups represented by —OR ¹¹⁸ in R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ and R ¹¹⁷ in formula (Si-1) include methoxy, ethoxy, propoxy, isopropyloxy, butoxy, phenoxy group, tolyloxy group, naphthyloxy group, propenyloxy group (eg, allyloxy group), cyclohexyloxy group and the like.
Among them, R ¹¹⁴ , R ¹¹⁵ , R ¹¹⁶ and R ¹¹⁷ are preferably methyl group, ethyl group, propyl group and phenyl group.

The group represented by formula (Si-1) can be derived by reacting an acid anhydride with a silicon-containing compound having amino groups at both ends. Specific examples of such silicon-containing compounds include both terminal amino-modified methylphenyl silicones (for example, Shin-Etsu Chemical Co., Ltd., X-22-1660B-3 (number average molecular weight of about 4,400) and X-22-9409 ( number average molecular weight of about 1,300)), amino-modified dimethyl silicone at both ends (for example, manufactured by Shin-Etsu Chemical Co., Ltd., X-22-161A (number average molecular weight of about 1,600), X-22-161B (number average molecular weight of about 3, 000) and KF8012 (number average molecular weight of about 4,400); BY16-835U manufactured by Toray Dow Corning (number average molecular weight of about 900); and JNC Silaplane FM3311 (number average molecular weight of about 1000)). be done.

[Method for producing polyamic acid (D)]
Polyamic acid (D) having a structural unit represented by formula (d1) is typically a tetracarboxylic dianhydride represented by the above formula (d1-1) and the above formula (d3- 1) is a polymer obtained by reacting a diamine compound represented by 1) in a solvent, and is a polymer obtained by using one or more kinds of diamine compounds and/or tetracarboxylic dianhydrides, respectively, good too. For example, it may be a polymer obtained by polycondensation of a diamine compound and a mixture containing two or more tetracarboxylic dianhydrides. Moreover, polyamic acid (D) can be used individually or in mixture of 2 or more types.

The amount of the tetracarboxylic dianhydride and the diamine compound used when synthesizing the polyamic acid (D) is not particularly limited, but the diamine compound is 0.50 mol or more per 1 mol of the tetracarboxylic dianhydride. It is preferably used in an amount of 0.50 mol or less, more preferably 0.60 mol or more and 1.30 mol or less, and particularly preferably 0.70 mol or more and 1.20 mol or less.
The weight-average molecular weight of the obtained polymic acid (D) may be appropriately set according to its use, and is, for example, 5,000 or more, preferably 7,500 or more, and more preferably 10,000 or more. On the other hand, the weight average molecular weight of the resulting polymic acid (D) is, for example, 100,000 or less, preferably 80,000 or less, and more preferably 75,000 or less.
The weight-average molecular weight may be set to the value described above by adjusting the compounding amounts of the tetracarboxylic dianhydride and the diamine compound, and the reaction conditions such as the solvent and the reaction temperature.

The reaction between the tetracarboxylic dianhydride and the diamine compound is usually carried out in an organic solvent. The organic solvent used for the reaction of the tetracarboxylic dianhydride and the diamine compound is an organic solvent capable of dissolving the tetracarboxylic dianhydride and the diamine compound and not reacting with the tetracarboxylic dianhydride and the diamine compound. There is no particular limitation as long as it is a solvent. An organic solvent can be used individually or in mixture of 2 or more types.

Examples of the organic solvent used for the reaction between the tetracarboxylic dianhydride and the diamine compound include N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, Nitrogen-containing polar solvents such as N,N-diethylformamide, N-methylcaprolactam, and N,N,N',N'-tetramethylurea; dimethyl sulfoxide; acetonitrile; diethylene glycol dimethyl ether, diethylene glycol diethyl ether, dioxane, and tetrahydrofuran, etc. and ethers of

Among these organic solvents, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethyl Nitrogen-containing polar solvents such as formamide, N,N-diethylformamide, N-methylcaprolactam, and N,N,N',N'-tetramethylurea are preferred.

The temperature at which the tetracarboxylic dianhydride and the diamine compound are reacted is not particularly limited as long as the reaction proceeds well. Typically, the reaction temperature between the tetracarboxylic dianhydride and the diamine compound is preferably −5° C. or higher and 150° C. or lower, more preferably 0° C. or higher and 120° C. or lower, and particularly preferably 0° C. or higher and 70° C. or lower. . The time for reacting the tetracarboxylic dianhydride and the diamine compound varies depending on the reaction temperature, but is typically preferably 1 hour or more and 50 hours or less, more preferably 2 hours or more and 40 hours or less, and 5 hours. More than 30 hours or less is particularly preferable.

A solution containing polyamic acid (D) is obtained by the method described above.
As described above, the solution containing the polyamic acid (D) can be used as it is for the preparation of the composition. A paste or solid of polyamic acid obtained by removing at least part of the solvent from the solution of (1) can also be used for preparing the resin composition.

The composition according to the first aspect when further comprising at least one resin precursor or resin selected from the group consisting of a monomer component consisting of a diamine compound and a tetracarboxylic dianhydride, a polyamic acid (D), and a polyimide. The substance may contain a carbonyloxy compound (B1) having a --CO--O-- bond in the molecule, which does not fall under the salt represented by the general formula (1). Specific examples of the carbonyloxy compound (B1) include carboxylic acids, carboxylic acid esters, carboxylic acid anhydrides, carbonates, and the like described in JP-A-2018-58918.

When the composition according to the first aspect contains the carbonyloxy compound (B1), the content of the carbonyloxy compound (B1) is not particularly limited as long as the object of the present invention is not impaired. Based on the total amount of components (excluding the solvent), it is preferably 0.01% by mass or more and 30% by mass or less, more preferably 0.05% by mass or more and 25% by mass or less, and 0.2% by mass or more and 20% by mass or less. Especially preferred.

(Solvent (S))
The composition according to the first aspect preferably contains a solvent (S) in terms of coatability. The composition may be a paste containing solids or a solution, preferably a solution. A solvent (S) can be used individually or in mixture of 2 or more types.
The type of solvent (S) is not particularly limited as long as it does not interfere with the object of the present invention. Water, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl Glycol monoethers such as ethers, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, and diethylene glycol monophenyl ether; ethylene glycol dimethyl ether, ethylene glycol Glycol diethers such as diethyl ether, ethylene glycol dipropyl ether, propylene glycol dimethyl ether, propylene glycol diethyl ether, propylene glycol dipropyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, and diethylene glycol dipropyl ether; ethylene glycol monomethyl ether acetate, ethylene glycol Glycol monoacetates such as monoethyl ether acetate, ethylene glycol monopropyl ether acetate, ethylene glycol monobutyl ether acetate, ethylene glycol monophenyl ether acetate, diethylene glycol monomethyl ether acetate, and diethylene glycol monoethyl ether acetate; Butyl ether acetate, diethylene glycol monophenyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, 2-methoxybutyl acetate, 3-methoxybutyl acetate, 4-methoxybutyl acetate, 2-methyl -3-methoxybutyl acetate, 3-methyl-3-methoxybutyl acetate, 3-ethyl-3-methoxybutyl acetate, 2-ethoxybutyl acetate, 4-ethoxybutyl acetate, 4-propoxybutyl acetate, 2-methoxypentyl acetate , 3-methoxypentylacetate 4-methoxypentyl acetate, 2-methyl-3-methoxypentyl acetate, 3-methyl-3-methoxypentyl acetate, 3-methyl-4-methoxypentyl acetate, and 4-methyl-4-methoxypentyl acetate, etc. ketones such as acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, ethyl isobutyl ketone, and cyclohexanone; methyl propionate, ethyl propionate, propyl propionate, isopropyl propionate, 2- methyl hydroxypropionate, ethyl 2-hydroxypropionate, 2-hydroxy-2-methyl, methyl-3-methoxypropionate, ethyl-3-methoxypropionate, ethyl-3-ethoxypropionate, ethyl-3 -propoxypropionate, propyl-3-methoxypropionate, isopropyl-3-methoxypropionate, ethyl ethoxyacetate, ethyl oxyacetate, methyl 2-hydroxy-3-methylbutanoate, methyl acetate, ethyl acetate, propyl acetate , isopropyl acetate, butyl acetate, isoamyl acetate, methyl carbonate, ethyl carbonate, propyl carbonate, butyl carbonate, methyl pyruvate, ethyl pyruvate, propyl pyruvate, butyl pyruvate, methyl acetoacetate, ethyl acetoacetate, benzyl acetate, benzoin esters such as ethyl acetate, diethyl oxalate, diethyl maleate, and γ-butyrolactone; ethers such as diethyl ether, dipropyl ether, dibutyl ether, dihexyl ether, benzyl methyl ether, benzyl ethyl ether, and tetrahydrofuran; benzene, aromatics such as toluene, xylene, ethylbenzene, cresol, and chlorobenzene; aliphatic alcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, n-hexanol, and cyclohexanol; polyethylene glycol, ethylene glycol, Glycols such as diethylene glycol, propylene glycol, and dipropylene glycol; glycerin; and the like.
In addition, the solvent used for the reaction of the above-mentioned tetracarboxylic dianhydride and diamine compound is similarly exemplified, and the monomer component consisting of the diamine compound and tetracarboxylic dianhydride, the polyamic acid (D) and the polyimide It can be suitably used as a solvent in the composition according to the first aspect when it further contains at least one resin precursor or resin selected from the group.

（式（５）中、Ｒ^Ｓ１及びＲ^Ｓ２は、それぞれ独立に炭素原子数１以上３以下のアルキル基であり、Ｒ^Ｓ３は下式（５－１）又は下式（５－２）：

で表される基である。式（５－１）中、Ｒ^Ｓ４は、水素原子又は水酸基であり、Ｒ^Ｓ５及びＲ^Ｓ６は、それぞれ独立に炭素原子数１以上３以下のアルキル基である。式（５－２）中、Ｒ^Ｓ７及びＲ^Ｓ８は、それぞれ独立に水素原子、又は炭素原子数１以上３以下のアルキル基である。） A solvent containing a compound (S1) represented by the following formula (5) may also be used as the solvent (S).

(In formula (5), R ^S1 and R ^S2 are each independently an alkyl group having 1 to 3 carbon atoms, and R ^S3 is the following formula (5-1) or the following formula (5-2):

is a group represented by In formula (5-1), R ^S4 is a hydrogen atom or a hydroxyl group, and R ^S5 and R ^S6 are each independently an alkyl group having 1 to 3 carbon atoms. In formula (5-2), R ^{1 S7} and R ^{1 S8} are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. )

Specific examples of the compound (S1) represented by the formula (5) in which R ^{2 S3} is a group represented by the formula (5-1) include N,N,2-trimethylpropionamide, N -ethyl-N,2-dimethylpropionamide, N,N-diethyl-2-methylpropionamide, N,N,2-trimethyl-2-hydroxypropionamide, N-ethyl-N,2-dimethyl- 2-hydroxypropionic acid amide, N,N-diethyl-2-hydroxy-2-methylpropionic acid amide, and the like.

Specific examples of the compound (S1) represented by formula (5) in which R ^{3 S3} is a group represented by formula (5-2) include N,N,N',N'-tetramethyl urea, N,N,N',N'-tetraethylurea, and the like.

Among the above examples of compound (S1), N,N,2-trimethylpropionamide and N,N,N',N'-tetramethylurea are particularly preferred.

When the composition contains the solvent (S), the content of the aforementioned compound (S1) in the solvent (S) is not particularly limited as long as the object of the present invention is not impaired. The composition according to the first aspect when further comprising at least one resin precursor or resin selected from the group consisting of a monomer component consisting of a diamine compound and a tetracarboxylic dianhydride, a polyamic acid (D), and a polyimide. The ratio of the compound (S1) to the mass of the solvent of the substance is typically preferably 70% by mass or more, more preferably 80% by mass or more, and particularly preferably 90% by mass or more, relative to the total amount of the solvent (S). 100% by weight is most preferred.

Organic solvents that can be used together with compound (S1) include N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, hexamethylphosphoramide, 1,3-dimethyl-2 - nitrogen-containing polar solvents such as imidazolidinone; ketones such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and isophorone; cyclic ethers such as dioxane and tetrahydrofuran; aromatic hydrocarbons such as toluene and xylene; sulfoxides such as

The content of the solvent (S) in the composition is not particularly limited as long as the object of the present invention is not impaired. The content of the solvent (S) in the composition is appropriately adjusted according to the solid content in the composition. The solid content in the resin composition is, for example, in the range of 5% by mass to 99.9% by mass, preferably 5% by mass to 70% by mass, and more preferably 10% by mass to 60% by mass.

(Other ingredients)
The composition according to the first aspect may contain various resins or additives as necessary. Examples of resins include alkali-soluble resins and resins whose solubility in a developer (alkali developer or solvent developer) is increased by being exposed or heated. Moreover, the resin may or may not have an ethylenically unsaturated group. Additives include colorants, dispersants, sensitizers, curing accelerators, fillers, adhesion promoters, antioxidants, UV absorbers, aggregation inhibitors, thermal polymerization inhibitors, antifoaming agents, and surfactants. etc.
When the composition according to the first aspect contains the compound represented by the general formula (1), the content of the resin is, for example, 10% by mass or more and 90% by mass with respect to the entire composition excluding the solvent. It may be appropriately adjusted within the following range, preferably 20% by mass or more and 80% by mass or less. When the composition according to the first aspect contains a polymer derived from the compound represented by the general formula (1), the content of the resin is, for example, 1 mass with respect to the entire composition excluding the solvent % or more and 90 mass % or less, preferably 10 mass % or more and 80 mass % or less.
The amount of each additive added may be appropriately adjusted in the range of, for example, 0.001% by mass or more and 60% by mass or less, preferably 0.1 It is more than mass % and below 5 mass %.

The composition according to the first aspect may be a thermosetting composition that cures by heating, or may not be a thermosetting composition.
When the composition according to the first aspect is a thermosetting composition, the composition according to the first aspect may optionally include a curing agent, a curing accelerator, a dehydration condensation agent, an antioxidant, an ultraviolet absorbing Additives and reinforcements such as agents, flame retardants, release agents, plasticizers, fillers, and reinforcements may also be included.

Moreover, the composition according to the first aspect may be a radiation-sensitive composition, or may not be a radiation-sensitive composition, and the composition according to the first aspect is a radiation-sensitive composition. In this case, it may be a negative radiation-sensitive composition that becomes insoluble in a developer upon exposure, or a positive radiation-sensitive composition that becomes soluble in a developer upon exposure.
In addition, the composition according to the first aspect may be used as a treatment liquid (applications such as metal surface treatment, development treatment, etching treatment, etc.). When the composition according to the first aspect is a treatment liquid composition, it preferably contains the above solvent (S) in addition to the salt represented by formula (1). The treatment liquid composition may optionally contain additives such as pH adjusters, surfactants, preservatives, viscosity adjusters, antioxidants, UV absorbers, or colorants in amounts within the range in which they are usually used. may be included in

(Method for preparing composition according to first aspect)
The composition according to the first aspect is prepared by mixing the above components with a stirrer. In addition, filtration using a membrane filter or the like may be performed so that the prepared composition according to the first aspect is uniform.

(Application)
The composition according to the first aspect is a composition for forming a protective film, an interlayer insulating film, a flat film, an insulating film for electronic parts such as a display element, an integrated circuit element, and a solid-state imaging device, or a composition for forming these electron It can be used as a treatment agent or sacrificial film composition in the manufacturing process of parts.

≪Curified product≫
A cured product according to the second aspect is a cured product of the composition of the first aspect.
The cured product according to the second aspect can be used as protective films, interlayer insulating films, flat films, and insulating films for electronic components such as liquid crystal display devices, integrated circuit devices, and solid-state imaging devices.

When the cured product is a film, the thickness is preferably 10 nm or more and 30000 nm or less, more preferably 50 nm or more and 1500 nm or less, and even more preferably 100 nm or more and 1000 nm or less.

≪Method for producing cured product≫
A method for producing a cured product according to the third aspect comprises applying the composition of the first aspect (preferably onto a substrate) to form a film, and heating the film.
(Film forming process)
The method for forming a film by applying the composition of the first aspect is not particularly limited. A method of coating using a non-contact coating device such as a flow coater may be used.
It is preferable to dry (pre-bake) the coating film after the application. The drying method is not particularly limited. For example, (1) a method of drying on a hot plate at a temperature of 70° C. or higher and 120° C. or lower, preferably 80° C. or higher and 100° C. or lower, for example, for 60 seconds or longer and 20 minutes or shorter; 2) a method of leaving the sample at room temperature for several hours to several days;
After coating, the coating film may be placed in a reduced pressure atmosphere for the purpose of promoting degassing from the coating film and removal of the solvent (S). The degree of vacuum in the reduced-pressure atmosphere is not particularly limited, but is preferably 300 Pa or less, more preferably 150 Pa or less, and even more preferably 100 Pa or less.
The thickness of the coating film is not particularly limited. Typically, the thickness of the coating film is preferably 2 μm or more and 100 μm or less, more preferably 3 μm or more and 50 μm or less. The thickness of the coating film can be appropriately controlled by adjusting the coating method and the solid content concentration and viscosity of the resin composition.

The material of the substrate is not particularly limited as long as the material does not cause thermal deterioration or deformation when the coating film is heated. The shape of the substrate is also not particularly limited as long as the resin composition can be applied. Examples of the substrate include electronic elements such as semiconductor elements, intermediate products such as multilayer wiring boards, and various substrates on which electrodes and wiring to be insulated are formed. When the substrate is a substrate, suitable substrate materials include glass; silicon; aluminum (Al); aluminum-silicon (Al--Si), aluminum-copper (Al--Cu), aluminum-silicon-copper (Al -Si-Cu) and other aluminum alloys; titanium (Ti); titanium-titanium alloys such as tungsten (Ti-W); titanium nitride (TiN); tantalum (Ta); tantalum nitride (TaN); tungsten (W); tungsten nitride (WN); copper;
In addition, when the coating film is heated at a low temperature, a base material with low heat resistance made of a resin such as polyethylene terephthalate (PET) or polybutylene terephthalate (PBT) can be used.

(Heating process)
The coating film thus formed is preferably heated at 70° C. or higher and 550° C. or lower.
When the coating film is heated, the heating temperature is set to, for example, 120° C. or higher and 500° C. or lower, preferably 150° C. or higher and 450° C. or lower. By heating the coating film at a temperature within such a range, it is possible to stably produce a cured product while suppressing thermal deterioration and thermal decomposition of the produced polyimide.
In addition, when the coating film is heated at a high temperature, a large amount of energy is consumed and the aging of the treatment equipment at high temperatures may be accelerated, so it is also preferable to heat the coating film at a lower temperature. It is a mode.

The heating time depends on the composition of the resin composition, the thickness of the coating film, etc., but the lower limit is, for example, 5 minutes, preferably 10 minutes, more preferably 20 minutes, and the upper limit is, for example, 4 hours, preferably. can be 3 hours, more preferably 2.5 hours.
In addition, from the viewpoint of reducing the yellowness of polyimide and from the viewpoint of more smoothly converting polyamic acid to polyimide, the atmosphere during heating (gas composition such as oxygen concentration) can be adjusted, and the pressure reduction process can be performed during heating or before and after heating. can also be combined.

EXAMPLES The present invention will be described in more detail below based on examples, but the present invention is not limited by these examples.

（テトラカルボン酸二無水物の開環）
１００ｍｌの三口フラスコをヒートガンで加熱して十分に乾燥させた。次に、十分に乾燥させた上記三口フラスコ内の雰囲気ガスを窒素で置換して窒素雰囲気とした。次いで、上記三口フラスコ内に上記テトラカルボン酸二無水物（ＣｐＯＤＡ）を１．００ｇ（２．６０ｍｍｏｌ）を導入した後、更に、溶媒としてＮＭＰ（Ｎ－メチルピロリドン）を添加して撹拌して溶解液を得た。
次に、上記溶解液を含有する三口フラスコ内に、窒素雰囲気下を維持し塩酸１質量％濃度を１０ｍｌ添加して１時間撹拌した。
その後撹拌中の溶液に純水を投入することにより白色の沈殿物が発生し、吸引濾過を行い下記式で表されるテトラカルボン酸を固形物として０．９８ｇ（２．３３ｍｍｏｌ）得た。

上記テトラカルボン酸の^１Ｈ－ＮＭＲ（重ＤＭＳＯ，４００ＭＨｚ）の測定結果は以下の通りである。
δ（ｐｐｍ）：１２．１０－１１．７５（ＯＨ，４Ｈ），２．９０（ＣＨ，２Ｈ），２．６５（ＣＨ２，４Ｈ），２．３８（ＣＨ，２Ｈ），２．１８（ＣＨ２，４Ｈ），１．９２（ＣＨ２，２Ｈ），１．７８（ＣＨ，２Ｈ），１．７５－５８（ＣＨ，２Ｈ），１．１５（ＣＨ，２Ｈ） [Synthesis Example 1] Synthesis 1 of the salt represented by the general formula (1)
(Preparation of tetracarboxylic dianhydride)
According to the methods described in Synthesis Example 1, Example 1 and Example 2 of WO 2011/099518, a tetracarboxylic dianhydride (CpODA: norbornane-2-spiro-α-cyclo Pentanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic dianhydride) was prepared.

(Ring opening of tetracarboxylic dianhydride)
A 100-ml three-necked flask was heated with a heat gun to thoroughly dry it. Next, the atmospheric gas in the sufficiently dried three-necked flask was replaced with nitrogen to create a nitrogen atmosphere. Next, after introducing 1.00 g (2.60 mmol) of the tetracarboxylic dianhydride (CpODA) into the three-necked flask, NMP (N-methylpyrrolidone) is added as a solvent and dissolved by stirring. I got the liquid.
Next, 10 ml of hydrochloric acid having a concentration of 1% by mass was added to the three-necked flask containing the above solution while maintaining a nitrogen atmosphere, and the mixture was stirred for 1 hour.
After that, pure water was added to the stirred solution to generate a white precipitate, which was subjected to suction filtration to obtain 0.98 g (2.33 mmol) of a tetracarboxylic acid represented by the following formula as a solid matter.

The measurement results of ¹ H-NMR (heavy DMSO, 400 MHz) of the above tetracarboxylic acid are as follows.
δ (ppm): 12.10-11.75 (OH, 4H), 2.90 (CH, 2H), 2.65 (CH, 4H), 2.38 (CH, 2H), 2.18 (CH , 4H), 1.92 (CH, 2H), 1.78 (CH, 2H), 1.75-58 (CH, 2H), 1.15 (CH, 2H)

上記ジイミダゾール塩の^１Ｈ－ＮＭＲ（重ＤＭＳＯ，４００ＭＨｚ）の測定結果は以下の通りである。
カチオン帰属δ（ｐｐｍ）：７．０１（ＣＨ，４Ｈ），７．６５（ＣＨ，２Ｈ）
アニオン帰属δ（ｐｐｍ）：２．９０（ＣＨ，２Ｈ），２．６５（ＣＨ，２Ｈ），２．４０（ＣＨ２，２Ｈ），２．２０（ＣＨ，２Ｈ），１．９４（ＣＨ２，４Ｈ），１．７８（ＣＨ，２Ｈ），１．７５－１．５８（ＣＨ，４Ｈ），１．１５（ＣＨ，２Ｈ） (Synthesis of diimidazole salt)
0.42 g (1.00 mmol) of the above tetracarboxylic acid and 0.14 g (2.00 mmol) of imidazole were introduced into a mortar and pressurized for 15 minutes to obtain the target diimidazole salt represented by the following formula (hereinafter referred to as It may simply be referred to as "compound 1".) was obtained (yield: 0.55 g, yield: 98%, white solid).

The measurement results of ¹ H-NMR (heavy DMSO, 400 MHz) of the above diimidazole salt are as follows.
Cation assignment δ (ppm): 7.01 (CH, 4H), 7.65 (CH, 2H)
Anion assignment δ (ppm): 2.90 (CH, 2H), 2.65 (CH, 2H), 2.40 (CH, 2H), 2.20 (CH, 2H), 1.94 (CH, 4H ), 1.78 (CH, 2H), 1.75-1.58 (CH, 4H), 1.15 (CH, 2H)

テトラカルボン酸として上記式で表されるテトラカルボン酸を用いること以外は上述の（ジイミダゾール塩の合成）と同様にして下記式で表されるジイミダゾール塩（以下、単に「化合物２」ということがある。）を得た。

[Synthesis Example 2] Synthesis 2 of the salt represented by the general formula (1)

A diimidazole salt represented by the following formula (hereinafter simply referred to as "compound 2") is prepared in the same manner as in the above (Synthesis of diimidazole salt) except that the tetracarboxylic acid represented by the above formula is used as the tetracarboxylic acid. There is.)

[Synthesis Example 3] Preparation of polyamic acid A 30 ml three-necked flask was heated with a heat gun to dry it sufficiently. Next, the atmospheric gas in the three-necked flask was replaced with nitrogen to create a nitrogen atmosphere in the three-necked flask. After adding 0.90 mmol of 4,4′-diaminobenzanilide (DABAN) into a three-necked flask, N,N,N′,N′-tetramethylurea (TMU) was added. The contents of the three-necked flask were stirred to obtain a slurry in which the aromatic diamine (DABAN) was dispersed in the TMU.
Next, 0.90 mmol of the tetracarboxylic dianhydride (CpODA) was added to the three-necked flask, and then the contents of the flask were stirred at room temperature (25°C) for 12 hours under a nitrogen atmosphere to obtain a reaction solution. . Thus, a reaction liquid (polyamic acid solution) containing 20.0% by mass of polyamic acid was prepared.

[Examples 1 and 2]
(Preparation of the composition of Example 1)
0.9 g of the powder (compound 1) obtained in Synthesis Example 1 was added to the polyamic acid solution (concentration of polyamic acid: 20.0% by mass), and the mixture was dissolved by vigorously stirring, and the solvent and A composition of Example 1 containing the above polyamic acid and the above compound 1 (polyimide-forming mixed solution (varnish)) was prepared. In the thus-obtained mixed liquid for polyimide formation, the total content of the polyamic acid and the compound 1 was 16.5% by mass.

(Preparation of composition of Example 2)
Except for using the powder of the compound 2 obtained in Synthesis Example 2 instead of using the powder of the compound 1 obtained in Synthesis Example 1, the preparation of Example 2 was performed in the same manner as in (Preparation of the composition of Example 1). A composition (polyimide forming mixture (varnish)) was prepared.

(Preparation of composition of Comparative Example 1)
Further, the composition of Comparative Example 1 was prepared by the same method as in Example 1 except that imidazole was used instead of the compound 1 (polyimide-forming mixture (varnish)), that is, the solvent and the A composition containing polyamic acid and imidazole was prepared.

(Preparation of composition of Comparative Example 2)
In addition, the composition of Comparative Example 2 in which a composition (polyimide-forming mixture (varnish)) was prepared in the same manner as in Example 1 except that the compound 1 was not contained, that is, the solvent and the polyamic acid A composition containing

(Polyimide film formation test)
The film-forming properties of the compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were tested as follows.
First, each composition was spin-coated on a glass substrate of 100 mm×100 mm and vacuum dried (VCD) from atmospheric pressure to 50 Pa. Once returned to atmospheric pressure, pre-baked on a hot plate at 80 ° C. under atmospheric pressure for 10 minutes, then post-baked (baked) at 360 ° C. for 30 minutes in a nitrogen atmosphere to give a cured product with a film thickness of 15 μm ( Polyimide film) was obtained.
The polyimide film thus obtained was visually observed to see if it was formed in a good shape. In addition, evaluation was performed based on the following references|standards.
◯: A generally smooth film was observed, and no cracks were confirmed.
x: Cracks were observed in the film.
The results are shown in Table 1 below.

(Stability test over time)
The compositions of Examples 1 and 2 and Comparative Examples 1 and 2 were evaluated for stability over time based on the presence or absence of gelation after the initial stage of preparation and storage at 25 ° C. for 7 days (○: no gelation, ×: gel ). Table 1 shows the results.

As is clear from the results shown in Table 1, the composition of Comparative Example 1 containing imidazole, which is not a salt, was excellent in film-forming properties but inferior in stability over time. The composition of Comparative Example 2, which does not contain salt or imidazole, was excellent in stability over time, but inferior in film-forming properties.
On the other hand, the compositions of Examples 1 and 2 containing imidazole salts were both excellent in film-forming properties and stability over time.

Claims (6)

A composition containing a salt represented by the following formula (1).

(In the above formula, A contains 1 or 2 or more alicyclic groups, and n -COO ^- M ⁺ and (4-n) -COOH in the above formula are each independently the above 1 or 2 Represents a tetravalent organic group bonded directly or via a linking group to the above alicyclic group, M ⁺ represents a cation containing a nitrogen-containing heterocycle, and the cation is represented by the following formulas (2) to (8) ), a cation represented by any of (10) and (11), n represents an integer of 1 or more and 4 or less.)

(In formula (2), each R ¹¹ independently represents a hydrogen atom , an alkyl group or a cycloalkyl group, and s represents an integer of 2 or more and 6 or less.)

(In the formula, ^RH each independently represents a hydrogen atom or an alkyl group; ^R21 , ^R23 , ^R25 , ^R26 , ^R27 , ^R28 , ^R31 , and ^R32 each independently represent a hydrogen atom ; represents an alkyl group or a cycloalkyl group , and R ²² , R ²⁴ and R ²⁹ each independently represent a hydrogen atom, an alkyl group or a cycloalkyl group ;
R ²¹ and R ²² may combine with each other to form a ring. At least two R ²¹ may combine with each other to form a ring. R ²³ and R ²⁴ may combine with each other to form a ring. Two R ²³ may combine with each other to form a ring. At least two R ²⁵ may combine with each other to form a ring. At least two R ²⁶ may combine with each other to form a ring. At least two R ²⁷ may be bonded together to form a ring. R ²⁸ and R ²⁹ may combine with each other to form a ring. At least two R ²⁸ may be bonded together to form a ring. At least two R ³¹ may be bonded together to form a ring. At least two R ³² may be bonded together to form a ring. ) The composition according to claim 1, further comprising at least one resin precursor or resin selected from the group consisting of a monomer component consisting of a diamine component and a tetracarboxylic dianhydride component, polyamic acids and polyimides. A cured product of the composition according to claim 2 . applying the composition of claim 2 to form a film; and
A method for producing a cured product, comprising heating the film. A salt represented by the following formula (1).

(In the above formula, A contains 1 or 2 or more alicyclic groups, and n -COO ^- M ⁺ and (4-n) -COOH in the above formula are each independently the above 1 or 2 Represents a tetravalent organic group bonded directly or via a linking group to the above alicyclic group, M ⁺ represents a cation containing a nitrogen-containing heterocycle, and the cation is represented by the following formulas (2) to (8) ), a cation represented by any of (10) and (11), n represents an integer of 1 or more and 4 or less.)

(In formula (2), each R ¹¹ independently represents a hydrogen atom , an alkyl group or a cycloalkyl group, and s represents an integer of 2 or more and 6 or less.)

(In the formula, ^RH each independently represents a hydrogen atom or an alkyl group; ^R21 , ^R23 , ^R25 , ^R26 , ^R27 , ^R28 , ^R31 , and ^R32 each independently represent a hydrogen atom ; represents an alkyl group or a cycloalkyl group , and ^{R 22} , R ²⁴ and R ²⁹ each independently represents a hydrogen atom , an alkyl group or a cycloalkyl group ;
R ²¹ and R ²² may combine with each other to form a ring. At least two R ²¹ may combine with each other to form a ring. R ²³ and R ²⁴ may combine with each other to form a ring. Two R ²³ may combine with each other to form a ring. At least two R ²⁵ may combine with each other to form a ring. At least two R ²⁶ may combine with each other to form a ring. At least two R ²⁷ may be bonded together to form a ring. R ²⁸ and R ²⁹ may combine with each other to form a ring. At least two R ²⁸ may be bonded together to form a ring. At least two R ³¹ may be bonded together to form a ring. At least two R ³² may be bonded together to form a ring. ) 6. An agent for suppressing deterioration over time of a composition for forming a polyimide film and improving film-forming properties, comprising the salt according to claim 5.