WO2023080007A1 - Polyimide production method, polyimide, polyimide resin composition, and cured product thereof - Google Patents

Abstract

The present invention pertains to: a polyimide production method comprising a step (1) for obtaining a polyimide by causing a reaction between (b) a diamine and (a) a tetracarboxylic acid and/or a tetracarboxylic acid dianhydride in a temperature range of 80-250°C in a reaction solvent containing 60-100 mass% of water with respect to a total of 100 mass% of the reaction solvent, and a step (2) for performing chain extension of the obtained polyimide; or a polyimide production method comprising a step (3) for obtaining a polyimide by causing a reaction between (e) a diamine having a purity of 98 mass% or more and (d) a tetracarboxylic acid dianhydride having a purity of 98 mass% or more in a temperature range of 100-370°C in a reaction solvent containing 60-100 mass% of water with respect to a total of 100 mass% of the reaction solvent.　Provided are: a method that is for producing a polyimide suitable for an interlayer insulation film and a surface protective film for electronic components, etc., and that enables the usage amount of organic solvents to be reduced; said polyimide, a resin composition containing said polyimide; and a cured product formed from the resin composition.

Description

Method for producing polyimide, polyimide, polyimide resin composition and cured product thereof

The present invention relates to a method for producing a polyimide that can reduce the amount of organic solvent used and is suitable for surface protective films of electronic parts, interlayer insulating films, etc., the polyimide, a resin composition containing the polyimide, and a cured product thereof.

Due to its high heat resistance and excellent mechanical and electrical properties, polyimide is used for surface protective films and interlayer insulating films of electronic parts. Along with the recent demand for high performance electronic components, polyimide has improved reproducibility of pattern formation after development, high transmittance and neutral color appearance when made into a film, and cure shrinkage on the coated substrate. Small things are required.

As a general method for producing polyimide, an aromatic tetracarboxylic acid anhydride and an aromatic diamine are reacted in an amide-based polar organic solvent such as N-methyl-2-pyrrolidone (hereinafter, NMP). , a method of obtaining polyimide via polyamic acid is known. However, in recent years, from the perspective of protecting human health and the environment, there has been a growing movement to avoid the inclusion of chemical substances such as NMP in products. A method is desired. In the conventional method for producing polyimide, a method of reprecipitating the polyimide solution in a large amount of poor solvent such as water in the polymer recovery process is known in order to remove the amide-based polar organic solvent used in the production. In Patent Document 1, in order to efficiently remove NMP, a low boiling point solvent such as ethyl acetate and water are added to the NMP reaction solution of polyimide to separate it into an organic layer and an aqueous layer, and then the aqueous layer is removed. As a method for producing a polyimide precursor, a method is disclosed in which the operation of removing NMP by rinsing is repeated about three times. In Patent Documents 2 to 5, as a method for producing polyimide that reduces the amount of organic solvent used, surface protective films and interlayer insulation of electronic parts are produced by reacting at a temperature exceeding 100 ° C. under high pressure in a water solvent. Techniques have been disclosed for polymerizing thermoplastic polyimides that are not intended for membranes.

Also, as a method for producing polyimide with a reduced amount of organic solvents such as NMP, a method of polymerizing tetracarboxylic acid and diamine in a solid phase without using a solvent is known (Non-Patent Document 1). Further, Patent Document 6 discloses a method of preparing a nylon salt-type monomer from a tetracarboxylic acid and a diamine in a solvent and subjecting it to solid phase polymerization to obtain a polyimide.

Patent No. 6503341 Japanese Patent Application Laid-Open No. 2001-181389 Japanese Patent Application Laid-Open No. 2001-270945 Patent No. 4050458 Patent No. 6994946 JP 2015-98573 A

"Latest Polyimide - Fundamentals and Applications -", edited by Japan Polyimide and Aromatic Polymer Study Group, p23, 2010

However, in the method described in Patent Document 1, the NMP in the polyimide is reduced to below the gas chromatography detection limit by going through this multi-step washing process, but the organic solvent used for washing is in the polyimide. This is undesirable from an environmental, safety and health standpoint. In addition, in the methods described in Patent Documents 2 to 5, polyimide is synthesized in a polymerization solvent containing 80% by weight or more of water, but the molecular weight of the polyimide obtained is highly dependent on the reaction temperature, and the degree of polymerization is sufficient. High temperature and high pressure are essential to obtain , and the resulting polyimide tends to be colored due to impurities contained in the raw materials, and its optical properties are polyimides that meet the characteristics for application to applications including the development process. There was a problem in obtaining

Furthermore, the methods described in Non-Patent Document 1 and Patent Document 6 require higher temperature and longer time than the reaction using a solvent because the movement of molecules is controlled. It is considered that this is because the resulting polyimide has strong intermolecular interactions. Therefore, the obtained polyimide tends to have high crystallinity, and there is a problem that an insoluble and non-melting portion tends to occur.

In order to solve the above problems, the method for producing polyimide of the present invention has the following configuration. i.e.
[1] Tetracarboxylic acid and/or tetracarboxylic dianhydride (a) and diamine (b) are mixed in a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent, A method for producing a polyimide, comprising a step (2) of chain extension of the obtained polyimide after the step (1) of obtaining a polyimide by reacting it at a temperature range of 80 ° C. or more and 250 ° C. or less,
[2] The method for producing a polyimide according to [1] above, wherein the chain extension step (2) is a solid phase polymerization step (2a),
[3] The method for producing a polyimide according to [1] above, wherein the chain extension step (2) is a step (2b) of obtaining a polyimide by reacting at a temperature higher than that of the step (1),
[4] The method for producing a polyimide according to any one of [1] to [3], wherein in the step (1), the polyimide is obtained by reacting at a temperature range of 80° C. or higher and 140° C. or lower;
[5] The method for producing a polyimide according to [2] above, wherein in the step (2a), the solid state polymerization is performed at a temperature range of 80° C. or higher and 250° C. or lower.
[6] The method for producing a polyimide according to any one of [1] to [5], wherein the monoamine (c) is further reacted in the step (1).
[7] The tetracarboxylic acid and / or tetracarboxylic dianhydride (a) contains one or more selected from the group consisting of compounds represented by formula (1) [1] to [6 ] A method for producing a polyimide according to any one of

(In formula (1), R ₅ and R ₁₂ each independently represent an oxygen atom, C(CH ₃ ) ₂ , C(CF ₃ ) ₂ or SO ₂ , R ₆ and R ₇ each independently , a hydrogen atom, a hydroxyl group, a sulfonic acid group or a thiol group, and R ₈ , R ₉ , R ₁₀ , R ₁₁ , R ₁₃ and R ₁₄ each independently represent a hydrogen atom, a hydroxyl group, a sulfonic acid group, a thiol group or Indicates an alkyl group having 1 to 6 carbon atoms.)
[8] In a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent, a tetracarboxylic dianhydride (d) with a purity of 98% by mass or more and a A method for producing a polyimide, comprising the step (3) of reacting a diamine (e) in a temperature range of 100° C. or higher and 370° C. or lower to obtain a polyimide,
[9] The method for producing a polyimide according to [8], wherein in the step (3), a monoamine (f) having a purity of 97% by mass or more is further reacted.

The polyimide of the present invention has the following constitution. i.e.
[10] It has a structural unit represented by formula (2), contains an organic solvent of 1% by mass or less, has a yellowness of 0 to 3.0, and has a weight average molecular weight of 5,000 to 100. ,000 polyimide,

(In formula (2), R ₁ represents a 4- to 14-valent organic group having 5 to 40 carbon atoms, R ₂ represents a 2- to 12-valent organic group having 5 to 40 carbon atoms, and R ₃ and R ₄ are Each independently represents a hydroxyl group, a sulfonic acid group, a thiol group or an organic group having 1 to 20 carbon atoms, and α and β each independently represents an integer from 0 to 10 satisfying α+β≧1.)
[11] The polyimide according to [10] above, wherein the content of the organic solvent is 0.1% by weight or less,
[12] The polyimide according to [10] or [11], which is alkali-soluble,
[13] The polyimide according to any one of [10] to [12], wherein at least one of the main chain terminals of the polyimide is blocked with a terminal blocker.

The polyimide resin composition of the present invention has the following constitution. i.e.
[14] A polyimide resin composition containing the polyimide according to any one of [10] to [13], a photosensitizer and a solvent.

The cured product of the present invention has the following constitution. i.e.
[15] A cured product obtained by curing the polyimide resin composition according to [14] above.

The present invention can reduce the amount of organic solvent used, has excellent solvent solubility, and has a low yellowness, and a method for producing a polyimide suitable for a surface protective film of an electronic component, an interlayer insulating film, etc., the polyimide, and the polyimide and a cured film formed from the resin composition.

The present invention will be described in detail below.

The method for producing polyimide of the present invention has either the following first aspect or second aspect. i.e.
Tetracarboxylic acid and/or tetracarboxylic dianhydride (a) and diamine (b) are heated at 80° C. or higher in a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent. A method for producing a polyimide, comprising a step (1) of obtaining a polyimide by reaction in a temperature range of 250° C. or less, followed by a step (2) of chain extension of the obtained polyimide, or
In a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent, a tetracarboxylic dianhydride (d) with a purity of 98% by mass or more and a diamine (e) with a purity of 98% by mass or more ) in a temperature range of 100° C. or higher and 370° C. or lower to obtain a polyimide (3).

The polyimide referred to in the present invention is, for example, a structural unit derived from a tetracarboxylic acid and/or a tetracarboxylic dianhydride by reacting a tetracarboxylic acid and/or a tetracarboxylic dianhydride with a diamine. A copolymer in which structural units derived from diamine are bonded via imide bonds.

Examples of the tetracarboxylic acid and/or tetracarboxylic dianhydride used in the method for producing a polyimide of the present invention include aromatic tetracarboxylic acid, alicyclic tetracarboxylic acid, and dianhydrides thereof. , but not limited to. Moreover, these may be used individually or in combination of 2 or more types.

Specific examples of the tetracarboxylic acid and/or tetracarboxylic dianhydride (a) include 4- to 14-valent tetracarboxylic acids and tetracarboxylic dianhydrides having 5 to 40 carbon atoms, such as pyromellit acid, 3,3′,4,4′-biphenyltetracarboxylic acid, 2,3,3′,4′-biphenyltetracarboxylic acid, 2,2′,3,3′-biphenyltetracarboxylic acid, 3,3 ',4,4'-benzophenonetetracarboxylic acid, 2,2',3,3'-benzophenonetetracarboxylic acid, 2,2-bis(3,4-dicarboxyphenyl)propane, 2,2-bis(2 ,3-dicarboxyphenyl)propane, 1,1-bis(3,4-dicarboxyphenyl)ethane, 1,1-bis(2,3-dicarboxyphenyl)ethane, bis(3,4-dicarboxyphenyl) ) methane, bis(2,3-dicarboxyphenyl)methane, bis(3,4-dicarboxyphenyl)sulfone, 4,4′-oxydiphthalic acid, 1,2,5,6-naphthalenetetracarboxylic acid, 9, 9-bis(3,4-dicarboxyphenyl)fluoric acid, 9,9-bis{4-(3,4-dicarboxyphenoxy)phenyl}fluoric acid, 2,3,6,7-naphthalenetetracarboxylic acid, Aromatic tetracarboxylic acids such as 2,3,5,6-pyridinetetracarboxylic acid, 3,4,9,10-perylenetetracarboxylic acid, and 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane , 3,3′,4,4′-diphenylsulfonetetracarboxylic acid, 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,4, 5-cyclohexanetetracarboxylic acid, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid, 2,3,5-tricarboxy-2-cyclopentaneacetic acid, Residues of 2,3,4,5-tetrahydrofurantetracarboxylic acid and 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid , 4-(2,5-dioxotetrahydrofuran-3-yl)-4methyl-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid, 4-(2,5-dioxotetrahydrofuran-3 -yl)-7 methyl-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid, norbornane-2-spiro-2′-cyclopentanone-5′-spiro-2″-norbornane-5, 5″,6,6″-tetracarboxylic acid, norbornane-2-spiro-2′-cyclohexanone-6′-spiro-2″-norbornane-5,5″,6,6″-tetracarboxylic acid, and these Some of the hydrogen atoms of the aromatic ring or hydrocarbon are substituted with an alkyl group having 1 to 10 carbon atoms, a fluoroalkyl group, a halogen atom, etc., or a dianhydride thereof. Not limited. Also, two or more of these tetracarboxylic acids and tetracarboxylic dianhydrides may be used in combination.

Among these, the tetracarboxylic dianhydride preferably contains one or more selected from the group consisting of the compounds represented by formula (1).

In formula (1), R ₅ and R ₁₂ each independently represent an oxygen atom, C(CH ₃ ) ₂ , C(CF ₃ ) ₂ or SO ₂ , R ₆ and R ₇ each independently represents _a hydrogen _atom , _a hydroxyl group, a sulfonic acid group or _{a thiol group} ; It represents an alkyl group of numbers 1-6.

Among them, pyromellitic dianhydride, bis(3,4-dicarboxyphenyl)sulfone dianhydride, 4,4′-oxydiphthalic anhydride, 2,2-bis(3,4-dicarboxyphenyl)hexafluoro propane dianhydride, 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic dianhydride or an alkyl group on the aromatic ring thereof or a halogen atom-substituted compound is particularly preferred. These are used alone or in combination of two or more.

Examples of diamines used in the production method of the present invention include, but are not limited to, aromatic diamines and alicyclic diamines. Moreover, these may be used individually or in combination of 2 or more types.

Specific examples of the diamine (b) include diamines having 5 to 40 carbon atoms to 12-valent diamines, such as 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,4'-diamino Diphenylmethane, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfide, 4,4'- Diaminodiphenyl sulfide, 1,4-bis(4-aminophenoxy)benzene, benzine, m-phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, bis(4-aminophenoxyphenyl) ) sulfone, bis(3-aminophenoxyphenyl)sulfone, bis(4-aminophenoxy)biphenyl, bis{4-(4-aminophenoxy)phenyl}ether, 1,4-bis(4-aminophenoxy)benzene, 1 , 3-bis(4-aminophenoxy)benzene, 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-diethyl-4,4′-diaminobiphenyl, 3,3′-dimethyl-4 ,4′-diaminobiphenyl, 3,3′-diethyl-4,4′-diaminobiphenyl, 2,2′,3,3′-tetramethyl-4,4′-diaminobiphenyl, 3,3′,4, 4'-tetramethyl-4,4'-diaminobiphenyl, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, bis(3-amino-4-hydroxyphenyl)ether, bis(3 -amino-4-hydroxyphenyl)methylene, bis[N-(3-aminobenzoyl)-3-amino-4-hydroxyphenyl]sulfone, bis[N-(4-aminobenzoyl)-3-amino-4-hydroxy phenyl]sulfone, bis(3-amino-4-hydroxyphenyl)sulfone, bis(3-amino-4-hydroxyphenyl)propane, 2,2'-bis[N-(3-aminobenzoyl)-3-amino- 4-hydroxyphenyl]propane, 2,2′-bis[N-(4-aminobenzoyl)-3-amino-4-hydroxyphenyl]propane, 9,9-bis(3-amino-4-hydroxyphenyl)fluorene , 9,9-bis[N-(3-aminobenzoyl)-3-amino-4-hydroxyphenyl]fluorene, 9,9-bis[N-(4-aminobenzoyl)-3-amino-4-hydroxyphenyl ] Fluorene, N,N′-bis(3-aminobenzoyl)-2,5-diamino-1,4-dihydroxybenzene, N,N′-bis(4-aminobenzoyl)-2,5-diamino-1, 4-dihydroxybenzene, N,N'-bis(4-aminobenzoyl)-4,4'-diamino-3,3-dihydroxybiphenyl, N,N'-bis(3-aminobenzoyl)-3,3'- diamino-4,4-dihydroxybiphenyl, N,N'-bis(4-aminobenzoyl)-3,3'-diamino-4,4-dihydroxybiphenyl, 3,3'-diamino-4,4'-biphenol, bis(3-amino-4-hydroxyphenyl)methane, 1,1-bis(3-amino-4-hydroxyphenyl)ethane, 2,2-bis(3-amino-4-hydroxyphenyl)propane, 2,2 -bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis(3-amino-4-hydroxyphenyl) Aromatic diamines such as hexafluoropropane, and compounds in which some of the hydrogen atoms of these aromatic rings or hydrocarbons are substituted with alkyl groups having 1 to 10 carbon atoms, fluoroalkyl groups, halogen atoms, etc. can be, but are not limited to: In addition, in the method for producing a polyimide of the present invention, two or more of these diamines may be used in combination.

Above all, it is preferable that the diamine contains one or more selected from the group consisting of compounds represented by formula (3).

In formula (3), R ₁₅ represents an oxygen atom, C(CH _{3 ) 2} , C(CF ₃ ) ₂ or SO 2 , R ₁₆ and R ₁₇ each independently represents a hydrogen atom, a hydroxyl group, a sulfonic acid or a thiol group, especially when it is a hydroxyl group, the resulting polyimide is easily dissolved in an alkaline aqueous solution, and the dissolution rate in the alkaline aqueous solution, which is the developer used for development, increases, and the cured portion of the resin composition coating film and It is preferable because the dissolution contrast of the uncured portion is increased and fine pattern workability can be easily obtained.

Among these, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl sulfone, 4,4′-diaminodiphenyl sulfone, 3,4′-diaminodiphenyl sulfide, 4,4 '-diaminodiphenyl sulfide, bis(4-aminophenoxyphenyl)sulfone, bis(3-aminophenoxyphenyl)sulfone, bis(4-aminophenoxy)biphenyl, bis{4-(4-aminophenoxy)phenyl}ether, 1 ,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2-bis [4-(4-aminophenoxy)phenyl]propane, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, and compounds in which the aromatic rings of these are substituted with alkyl groups or halogen atoms, etc. It is mentioned as a preferable one. These are used alone or in combination of two or more.

In addition, in the method for producing a polyimide of the present invention, it is preferable that the monoamine (c) is further reacted in the step (1). By reacting in this manner, the ends of the polymer main chain can be end-capped with monoamines. End capping can be achieved, for example, by substituting a monoamine for a portion of the diamine. Examples of monoamines include, but are not limited to, aromatic monoamines and alicyclic monoamines. Moreover, these may be used individually or in combination of 2 or more types.

Specific examples of monoamines include 5-amino-8-hydroxyquinoline, 1-hydroxy-7-aminonaphthalene, 1-hydroxy-6-aminonaphthalene, 1-hydroxy-5-aminonaphthalene, 1-hydroxy -4-aminonaphthalene, 2-hydroxy-7-aminonaphthalene, 2-hydroxy-6-aminonaphthalene, 2-hydroxy-5-aminonaphthalene, 1-carboxy-7-aminonaphthalene, 1-carboxy-6-aminonaphthalene , 1-carboxy-5-aminonaphthalene, 2-carboxy-7-aminonaphthalene, 2-carboxy-6-aminonaphthalene, 2-carboxy-5-aminonaphthalene, 2-aminobenzoic acid, 3-aminobenzoic acid, 4 -aminobenzoic acid, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 3-amino-4,6-dihydroxypyrimidine, 2-aminophenol, 3-aminophenol, 4-aminophenol, 2-aminothio Phenol, 3-aminothiophenol, 4-aminothiophenol, 2-anilinesulfonic acid, 3-anilinesulfonic acid, 4-anilinesulfonic acid, and some of the hydrogen atoms of these aromatic rings and hydrocarbons Examples include, but are not limited to, compounds substituted with an alkyl group of number 1 to 10, a fluoroalkyl group, a halogen atom, or the like. Moreover, in the method for producing a polyimide of the present invention, two or more of these monoamines may be used in combination.

Above all, the monoamine (c) preferably has one or more substituents selected from the group consisting of hydroxyl groups, sulfonic acid groups and thiol groups. By using these monoamines, the resin composition containing the polyimide of the present invention tends to exhibit excellent storage stability and good workability, which is preferable.

In the first aspect of the method for producing a polyimide of the present invention, in a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent, tetracarboxylic acid and / or tetracarboxylic acid di The process includes a step (1) of reacting anhydride (a) and diamine (b) in a temperature range of 80° C. or higher and 250° C. or lower to obtain a polyimide.

The reaction solvent used in step (1) of the present invention and step (3) described later contains 60 to 100% by mass of water with respect to 100% by mass of the reaction solvent as a whole. In addition, as a reaction solvent, for example, alcohols such as ethanol, methanol, isopropyl alcohol and tert-butyl alcohol, glycols such as ethylene glycol, diethylene glycol, propylene glycol, polyethylene glycol and ethylene glycol ether, tetrahydrofuran, diethyl ether, dioxane, Ethers such as propylene glycol monomethyl ether, polar aprotic solvents such as γ-butyrolactone, ketones such as acetone, methyl ethyl ketone, diisobutyl ketone, and diacetone alcohol, esters such as ethyl acetate, propylene glycol monomethyl ether acetate, and ethyl lactate. Organic solvents such as aromatic hydrocarbons such as toluene and xylene can be used.

In a general polyimide polymerization reaction in an organic solvent, polyimide is produced via polyamic acid, which is a polyimide precursor. On the other hand, in the polymerization reaction of the polyimide of the present invention, tetracarboxylic acid and/or tetracarboxylic dianhydride and diamine form a salt in the reaction solvent without going through the polyamic acid, and dehydration polycondensation takes place from this monomer salt. It is believed that it proceeds to produce polyimide. In order for the polyimide polymerization reaction to proceed without passing through the polyamic acid of the present invention, the reaction solvent must contain 60% by mass or more of water, preferably 70% by mass or more, more preferably 80% by mass or more, and further. It is preferably 90% by mass, most preferably 100% by mass. Moreover, since the organic solvent contained in the reaction solvent is less than 40% by mass, the organic solvent hardly remains in the polyimide obtained by the production method of the present invention. From this viewpoint, the organic solvent contained in the reaction solvent is less than 40% by mass, preferably less than 30% by mass, more preferably less than 20% by mass, even more preferably less than 10% by mass, and most preferably 0% by mass.

In addition, the total amount of tetracarboxylic acid and/or tetracarboxylic dianhydride, diamine, and monoamine, which are reaction raw materials used in step (1) and step (3) described later, is the reaction solvent, tetracarboxylic acid and/or tetracarboxylic acid, and Based on the total amount of 100% by mass of the acid dianhydride, diamine and monoamine, it is preferably 1% by mass or more from the viewpoint of easiness of the imide bond generation reaction, and more preferably 5% by mass or more. 10% by mass or more is more preferable. From the viewpoint of suppressing undesirable side reactions occurring during the reaction, the content is preferably 50% by mass or less, more preferably 40% by mass or less, and more preferably 35% by mass or less.

In addition, a catalyst may be used in step (1) of the present invention and step (3) described later. The catalyst here is not particularly limited as long as it is a compound that has the effect of promoting the progress of the dehydration polycondensation reaction or suppressing the progress of side reactions such as cross-linking and oxidation. Examples include organic base catalysts and acid catalysts. be done. Organic base catalysts include triethylamine, tributylamine, tripentylamine, N,N-dimethylaniline, N,N-diethylaniline, pyridine, α-picoline, β-picoline, γ-picoline, 2,4-lutidine, 2 ,6-lutidine, quinoline, isoquinoline and the like. Acid catalysts include inorganic acids such as hydrochloric acid, hydrogen bromide, hydrogen iodide, sulfuric acid, sulfuric anhydride, nitric acid, phosphoric acid, phosphorous acid, phosphotungstic acid, and phosphomolybdic acid, as well as methanesulfonic acid, ethanesulfonic acid, and trifluoromethane. Sulfonic acids such as sulfonic acid, benzenesulfonic acid and p-toluenesulfonic acid; carboxylic acids such as acetic acid and oxalic acid; and halogenated carboxylic acids such as chloroacetic acid, dichloroacetic acid, trichloroacetic acid, fluoroacetic acid, difluoroacetic acid and trifluoroacetic acid. etc. can be exemplified. These catalysts may be used alone or in combination of two or more.

The reaction temperature in step (1) of the present invention must be a temperature at which the tetracarboxylic acid and/or tetracarboxylic dianhydride used in the reaction and the diamine react to form an imide bond, so the lower limit is 80°C. is. The temperature is preferably 100° C. or higher, more preferably 120° C. or higher, from the viewpoint that a polyimide having a sufficiently high molecular weight can be obtained. In addition, the upper limit of the reaction temperature is 250° C. in order to avoid progress of cross-linking and decomposition of the monomer. Since it is necessary to cope with the vapor pressure of the reaction solvent, which increases as the reaction temperature rises, the temperature is preferably 230° C. or less from the viewpoint of the pressure resistance of the reaction vessel and the handleability of the reaction. In the step (1), the temperature is more preferably 200° C. or lower, still more preferably 160° C. or lower, and most preferably 140° C. or lower, from the viewpoint that the yellowness degree can easily be adjusted to the preferred range.

Further, in step (1) and step (3) described later, the reaction pressure is adjusted from the viewpoint that the tetracarboxylic acid and/or tetracarboxylic dianhydride used in the reaction and the diamine are likely to react to form an imide bond. , is preferably 0.1 MPa or more, more preferably 0.2 MPa or more, further preferably 0.4 MPa or more. Although there is no particular upper limit to the reaction pressure, it is preferably 20 MPa or less, more preferably 10 MPa or less, from the viewpoint of the pressure resistance of the reaction vessel and the handleability of the reaction.

In addition, in step (1) and step (3) described later, the reaction time depends on the type and amount of raw materials used or the reaction temperature, and cannot be generally defined, but is preferably 0.1 hour or longer. , more preferably 0.5 hours or longer, and more preferably 1 hour or longer. When the time is longer than this preferable time, there is a tendency that unreacted raw material components can be sufficiently reduced. On the other hand, there is no particular upper limit to the reaction time, but the reaction proceeds sufficiently within 40 hours, preferably within 20 hours, and more preferably within 10 hours.

In addition, in the step (1) for producing a polyimide by the preferred method described above and the step (3) described later, there are no particular restrictions on the method and order of adding the reaction raw materials and solvent, and if necessary, the catalyst, etc. to the reaction vessel, but each They may be added all at once, or the reaction raw materials soluble in the reaction solvent may be dissolved in the reaction solvent in advance and then added. The method of carrying out the reaction is not particularly limited, but it is preferably carried out under stirring conditions. Furthermore, the atmosphere in step (1) and step (3) to be described later is preferably a non-oxidizing atmosphere, preferably an atmosphere of an inert gas such as nitrogen, helium, and argon, which is economical and easy to handle. It is preferable to carry out in a nitrogen atmosphere.

The first aspect of the method for producing polyimide of the present invention includes step (2) for chain extension of the polyimide obtained in step (1).

The chain extension step referred to in the present invention is a step for increasing the molecular weight of the polyimide, and the weight average molecular weight of the polyimide obtained in the step (1) is higher than the weight average molecular weight of the polyimide obtained in the step (1) after the step (2). The weight average molecular weight of the obtained polyimide becomes larger. The weight average molecular weight is measured by a gel permeation chromatography method (GPC method) and calculated in terms of polystyrene.

In the chain extension step of the step (2), the reaction solvent containing 60 to 100% by mass of water with respect to the solid phase polymerization step (2a) and the total 100% by mass of the reaction solvent is more than the step (1). A step (2b) of obtaining a polyimide by reaction at a high temperature can be preferably used.

The atmosphere in the solid phase polymerization step (2a) is preferably a non-oxidizing atmosphere or a reduced pressure. The term "non-oxidizing atmosphere" refers to an atmosphere having an oxygen concentration of 5% by volume or less, preferably 2% by volume or less, more preferably substantially free of oxygen in the gas phase in contact with the polyimide to be subjected to solid phase polymerization, i.e. nitrogen, It refers to an atmosphere of an inert gas such as helium or argon, and among these, a nitrogen atmosphere is particularly preferable from the viewpoint of economy and ease of handling. The pressure-reduced condition means that the pressure in the reaction system is lower than the atmospheric pressure, and the upper limit is preferably 50 kPa or less, more preferably 20 kPa or less, and even more preferably 10 kPa or less. As a lower limit, 0.1 Pa or more can be exemplified. This tends to suppress the occurrence of undesirable side reactions such as cross-linking reaction and decomposition reaction of polyimide.

The temperature in step (2a) is not particularly limited as long as it is a temperature at which the polyimide obtained in step (1) is increased in molecular weight. Carrying out the reaction at 80° C. or higher facilitates sufficiently increasing the molecular weight, which is preferable. It is more preferably 100° C. or higher, still more preferably 120° C. or higher, particularly preferably 150° C. or higher, and most preferably 180° C. or higher. In addition, the solid polyimide obtained in step (1) maintains a substantially solid state and is performed at a temperature at which the shape does not change. . It is more preferably 280° C. or lower, still more preferably 260° C. or lower, and most preferably 250° C. or lower.

In addition, the time in step (2a) is not particularly limited as long as the polyimide obtained in step (1) is sufficiently high in molecular weight. The above is preferable, and 72 hours or less is preferable from the viewpoint that undesirable side reactions such as cross-linking reaction and decomposition reaction can be suppressed. It is more preferably 5 hours or more and 48 hours or less, still more preferably 10 hours or more and 36 hours or less, and most preferably 12 hours or more and 24 hours or less.

In the step (2b) of obtaining a polyimide by reacting it in the reaction solvent at a temperature higher than that in the step (1), after recovering the polyimide obtained in the step (1) from the reaction solvent, adding it again to the reaction solvent, the step It is also possible to carry out the reaction at a higher temperature than in (1), and it is also possible to carry out the reaction at a higher temperature without recovering or cooling the polyimide after step (1). From the viewpoint of simplicity of the process, it is preferable to continue the reaction at elevated temperature without recovering or cooling the polyimide after the process (1).

The reaction temperature in step (2b) is higher than in step (1), preferably 10° C. or higher and 200° C. or lower, more preferably 20° C. or higher and 180° C. or lower than the reaction temperature in step (1), It is more preferably 30°C or higher and 150°C or lower, and most preferably 50°C or higher and 120°C or lower.

In addition, in step (2b), the reaction time is preferably 0.1 hours or longer, more preferably 0.5 hours or longer, and even more preferably 1 hour or longer. When the time is longer than this preferable time, there is a tendency that the molecular weight is sufficiently increased. On the other hand, there is no upper limit to the reaction time, but the reaction proceeds sufficiently within 40 hours, preferably within 20 hours, more preferably within 10 hours.

In addition, in the step (2b) of producing polyimide by the preferred method described above, the method of carrying out the reaction is not particularly limited, but it is preferably carried out under stirring conditions. Furthermore, the atmosphere in step (2b) is desirably a non-oxidizing atmosphere, preferably under an inert gas atmosphere such as nitrogen, helium, and argon, and from the viewpoint of economic efficiency and ease of handling, it is preferable to carry out under a nitrogen atmosphere. is preferred.

In the second aspect of the method for producing a polyimide of the present invention, a tetracarboxylic dianhydride having a purity of 98% by mass or more in a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent. and a step (3) of reacting the substance (d) with a diamine (e) having a purity of 98% by mass or more in a temperature range of 100° C. or higher and 370° C. or lower to obtain a polyimide.

The tetracarboxylic dianhydride used in the step (3) of the present invention includes, but is not limited to, the same compounds as the tetracarboxylic dianhydride described above in the explanation of step (1).

Although the structure of the tetracarboxylic dianhydride is not particularly limited, it has a purity of 98% by mass or more, preferably a purity of 99% by mass or more, and more preferably a purity of 99.5% by mass or more. By using a tetracarboxylic dianhydride with a purity of 98% by mass or more, a polyimide with reduced yellowness can be obtained. When the purity is less than 98% by mass, the resulting polyimide has a high degree of yellowness. The yellowness referred to here means that a polyimide solution in which polyimide is dissolved in an organic solvent is applied onto a substrate, and the solvent is removed by drying to prepare a polyimide film having a thickness of 10 μm. Shows a value calculated by measuring with a spectrophotometer.

The purity referred to in the present invention is the mass ratio of the main component to the total amount of the sample, and is expressed by purity=mass of main component/(mass of main component+mass of impurities). Purity can be determined by, for example, high performance liquid chromatography analysis, gas chromatography analysis, and ¹ H-NMR analysis. In high-performance liquid chromatography analysis, the peak area attributed to the main component in the sample is the peak area attributed to the sample-derived peak when the sample is divided into components by high-performance liquid chromatography equipped with a UV detector. It can be calculated as a percentage. The qualitative properties of each peak obtained by component separation by high-performance liquid chromatography can be performed by separating each peak by preparative liquid chromatography and performing absorption spectrum and mass spectrometry in infrared spectroscopic analysis.

Impurities contained in the tetracarboxylic dianhydride (d) having a purity of 98% by mass or more used in the present invention mainly originate from the production of the tetracarboxylic dianhydride, such as raw material carboxylic acids and carboxylic acid esters, Catalysts such as lower carboxylic acids (eg, formic acid, acetic acid, propionic acid, etc.), acetic anhydride, p-toluenesulfonic acid, sulfonic acid-type ion exchange resins, etc., and hydrolysates of tetracarboxylic dianhydrides.

The diamine used in the step (3) of the present invention includes the same compounds as the diamine described in the explanation of the step (1), but is not limited to these.

Above all, it is preferable that the diamine (e) having a purity of 98% by mass or more contains one or more selected from the group consisting of compounds represented by formula (3).

In formula (3), R ₁₅ represents an oxygen atom, C(CH _{3 ) 2} , C(CF ₃ ) ₂ or SO 2 , R ₁₆ and R ₁₇ each independently represents a hydrogen atom, a hydroxyl group, a sulfonic acid or a thiol group. Especially when it is a hydroxyl group, the obtained polyimide is easily dissolved in an alkaline aqueous solution, the dissolution rate in the alkaline aqueous solution which is the developer used for development increases, and the dissolution contrast between the cured part and the uncured part of the resin composition coating film is improved. It is preferable because it becomes large and fine pattern workability is easily obtained.

Although the structure of the diamine is not particularly limited, it has a purity of 98% by mass or more, preferably a purity of 99% by mass or more, and more preferably a purity of 99.5% by mass or more. By using a diamine having a purity of 98% by mass or more, a polyimide with suppressed yellow coloration can be obtained. If the purity is less than 98% by mass, the resulting polyimide tends to have a high degree of yellowness.

Impurities contained in the diamine (e) with a purity of 98% by mass or more used in the present invention include mainly compounds derived from the production of the diamine.

In addition, in the method for producing a polyimide of the present invention, it is preferable that a monoamine (f) having a purity of 97% by weight or more is further reacted in the step (3). By reacting in this manner, the ends of the polymer main chain can be end-capped with monoamines. End capping can be achieved, for example, by substituting a monoamine for a portion of the diamine. Examples of monoamines include, but are not limited to, aromatic monoamines and alicyclic monoamines. Moreover, these may be used individually or in combination of 2 or more types.

Specific examples of monoamines include, but are not limited to, compounds similar to those described above in the description of step (1). Moreover, in the method for producing the polyimide of the present invention, two or more of these monoamines may be used in combination.

The structure of the monoamine is not particularly limited, but preferably has a purity of 97% by mass or more, more preferably a purity of 98% by mass or more, still more preferably a purity of 99% by mass or more, and particularly preferably a purity of 99.5% by mass or more. is. By using a diamine having a purity of 97% by mass or more, a polyimide with suppressed yellow coloration can be obtained.

Impurities contained in the monoamine (f) with a purity of 97% by mass or more used in the present invention include mainly compounds derived from the production of the monoamine.

In the present invention, it is not clear why polyimides with reduced yellowness can be obtained by using tetracarboxylic dianhydrides, diamines, and monoamines with a purity within the above range. Since the reaction is carried out, side reactions caused by these impurities and oxidation of the impurity compounds are likely to occur, which is thought to cause an increase in the yellowness of the resulting colored polyimide. Therefore, it is believed that the use of a tetracarboxylic acid or diamine having a purity within the scope of the present invention suppresses the formation of such colored matter, resulting in a polyimide with a low degree of yellowness.

In the method for producing a polyimide of the present invention, a tetracarboxylic dianhydride (d) having a purity of 98% by mass or more in a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent, A step of reacting a diamine (e) having a purity of 98% by mass or more in a temperature range of 100° C. or higher and 370° C. or lower to produce a polyimide.

The reaction temperature in the second aspect of the method for producing a polyimide of the present invention must be a temperature at which the tetracarboxylic dianhydride and diamine used in the reaction react to form an imide bond, so the lower limit is 100°C. be. From the viewpoint of obtaining a polyimide having a sufficiently high molecular weight, the temperature is preferably 110° C. or higher, more preferably 120° C. or higher, still more preferably 160° C. or higher, and most preferably 180° C. or higher. In addition, the upper limit of the reaction temperature is 370° C. in order to avoid progress of cross-linking and decomposition of the monomer. Since it is necessary to cope with the vapor pressure of the reaction solvent that increases as the reaction temperature rises, it is preferably 310° C. or lower, more preferably 250° C. or lower, and still more preferably 250° C. or lower, from the viewpoint of the pressure resistance of the reaction vessel and the handleability of the reaction. is below 230°C.

The polyimide of the present invention is a polyimide having a structural unit represented by formula (2).

(In formula (2), R ₁ represents a 4- to 14-valent organic group having 5 to 40 carbon atoms, R ₂ represents a 2- to 12-valent organic group having 5 to 40 carbon atoms, and R ₃ and R ₄ are Each independently represents a hydroxyl group, a sulfonic acid group, a thiol group, or an organic group having 1 to 20 carbon atoms, and α and β are integers from 0 to 10 that satisfy α+β≧1.)
R ₁ in formula (2) represents a residue derived from a tetracarboxylic dianhydride, which is a tetravalent to 14valent organic group having 5 to 40 carbon atoms. R ₂ represents a residue derived from a diamine, and the diamine is a divalent to 14-valent organic group having 5 to 40 carbon atoms. Any one of R ₁ and R ₂ preferably contains at least one group selected from 1,1,1,3,3,3-hexafluoropropyl group, ether group, thioether group and SO ₂ group, Both R ₁ and R ₂ may be contained. In particular, both R ₁ and R ₂ preferably have at least one group selected from 1,1,1,3,3,3-hexafluoropropyl group, ether group, thioether group and SO ₂ group.

R ₃ and R ₄ each independently represent a hydroxyl group, a sulfonic acid group, a thiol group or an organic group having 1 to 20 carbon atoms, and α and β are integers from 0 to 10 satisfying α+β≧1 indicates From the viewpoint of imparting solvent solubility to the resulting polyimide, it is particularly preferred that R ₃ and R ₄ are hydroxyl groups.

R ₁ in formula (2) is a residue derived from a tetracarboxylic acid dianhydride having 5 to 40 carbon atoms and 4 to 14 valences. Examples of tetracarboxylic dianhydride residues include pyromellitic dianhydride, 3,3′,4,4′-biphenyltetracarboxylic dianhydride, 2,3,3′,4′-biphenyltetracarboxylic dianhydride, Carboxylic dianhydride, 2,2',3,3'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 2,2',3,3 '-benzophenonetetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, 1, 1-bis(3,4-dicarboxyphenyl)ethane dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride , bis(2,3-dicarboxyphenyl)methane dianhydride, bis(3,4-dicarboxyphenyl)sulfone dianhydride, 4,4'-oxydiphthalic anhydride, 1,2,5,6-naphthalene Tetracarboxylic dianhydride, 9,9-bis(3,4-dicarboxyphenyl)fluoric dianhydride, 9,9-bis{4-(3,4-dicarboxyphenoxy)phenyl}fluoric dianhydride 2,3,6,7-naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, aromatic tetracarboxylic dianhydrides such as 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, 3,3′,4,4′-diphenylsulfonetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 5 -(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic dianhydride, 2,3,5-tricarboxy-2-cyclopentaneacetic dianhydride, 2, Residues of 3,4,5-tetrahydrofurantetracarboxylic dianhydride and 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid dianhydride, 4-(2,5-dioxotetrahydrofuran-3-yl)-4methyl-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic dianhydride, 4-(2, 5-dioxotetrahydrofuran-3-yl)-7methyl-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic dianhydride, norbornane-2-spiro-2'-cyclopentanone-5' -spiro-2″-norbornane-5,5″,6,6″-tetracarboxylic dianhydride, norbornane-2-spiro-2′-cyclohexanone-6′-spiro-2″-norbornane-5,5″ ,6,6″-Tetracarboxylic acid dianhydride residues and some of the hydrogen atoms of these aromatic rings and hydrocarbons are replaced with alkyl groups having 1 to 10 carbon atoms, fluoroalkyl groups, halogen atoms, etc. Examples include, but are not limited to, residues of substituted compounds and the like. Moreover, the polyimide of the present invention may contain two or more of these tetracarboxylic dianhydride residues.

R ₂ in formula (2) is a residue derived from a diamine to 12-valent diamine having 5 to 40 carbon atoms. Diamine residues include, for example, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, 3, 4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 1,4-bis(4-aminophenoxy)benzene, benzine, m -phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, bis(4-aminophenoxyphenyl)sulfone, bis(3-aminophenoxyphenyl)sulfone, bis(4-aminophenoxy) Biphenyl, bis{4-(4-aminophenoxy)phenyl}ether, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 2,2'-dimethyl-4 ,4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-diethyl-4,4'-diamino biphenyl, 2,2',3,3'-tetramethyl-4,4'-diaminobiphenyl, 3,3',4,4'-tetramethyl-4,4'-diaminobiphenyl, 2,2'-bis (trifluoromethyl)-4,4'-diaminobiphenyl, bis(3-amino-4-hydroxyphenyl)ether, bis(3-amino-4-hydroxyphenyl)methylene, bis[N-(3-aminobenzoyl) -3-amino-4-hydroxyphenyl]sulfone, bis[N-(4-aminobenzoyl)-3-amino-4-hydroxyphenyl]sulfone, bis(3-amino-4-hydroxyphenyl)sulfone, bis(3 -amino-4-hydroxyphenyl)propane, 2,2'-bis[N-(3-aminobenzoyl)-3-amino-4-hydroxyphenyl]propane, 2,2'-bis[N-(4-amino benzoyl)-3-amino-4-hydroxyphenyl]propane, 9,9-bis(3-amino-4-hydroxyphenyl)fluorene, 9,9-bis[N-(3-aminobenzoyl)-3-amino- 4-hydroxyphenyl]fluorene, 9,9-bis[N-(4-aminobenzoyl)-3-amino-4-hydroxyphenyl]fluorene, N,N'-bis(3-aminobenzoyl)-2,5- diamino-1,4-dihydroxybenzene, N,N'-bis(4-aminobenzoyl)-2,5-diamino-1,4-dihydroxybenzene, N,N'-bis(4-aminobenzoyl)-4, 4'-diamino-3,3-dihydroxybiphenyl, N,N'-bis(3-aminobenzoyl)-3,3'-diamino-4,4-dihydroxybiphenyl, N,N'-bis(4-aminobenzoyl )-3,3′-diamino-4,4-dihydroxybiphenyl, 3,3′-diamino-4,4′-biphenol, bis(3-amino-4-hydroxyphenyl)methane, 1,1-bis(3 -amino-4-hydroxyphenyl)ethane, 2,2-bis(3-amino-4-hydroxyphenyl)propane, 2,2-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane, 2,2 - Residues of aromatic diamines such as bis[4-(4-aminophenoxy)phenyl]propane and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane, and aromatic rings and carbonization thereof Examples include, but are not limited to, residues of compounds in which a portion of the hydrogen atoms are substituted with an alkyl group having 1 to 10 carbon atoms, a fluoroalkyl group, a halogen atom, or the like. Moreover, the polyimide of the present invention may contain two or more of these diamine residues.

In addition, at least one of the main chain ends of the polyimide of the present invention preferably contains a structure blocked with a terminal blocking agent. Although the blocked structure is not particularly limited, a residue derived from monoamine can be preferably exemplified. Monoamine residues include, for example, 5-amino-8-hydroxyquinoline, 1-hydroxy-7-aminonaphthalene, 1-hydroxy-6-aminonaphthalene, 1-hydroxy-5-aminonaphthalene, 1-hydroxy-4- aminonaphthalene, 2-hydroxy-7-aminonaphthalene, 2-hydroxy-6-aminonaphthalene, 2-hydroxy-5-aminonaphthalene, 1-carboxy-7-aminonaphthalene, 1-carboxy-6-aminonaphthalene, 1- Carboxy-5-aminonaphthalene, 2-carboxy-7-aminonaphthalene, 2-carboxy-6-aminonaphthalene, 2-carboxy-5-aminonaphthalene, 2-aminobenzoic acid, 3-aminobenzoic acid, 4-aminobenzoic acid acid, 4-aminosalicylic acid, 5-aminosalicylic acid, 6-aminosalicylic acid, 3-amino-4,6-dihydroxypyrimidine, 2-aminophenol, 3-aminophenol, 4-aminophenol, 2-aminothiophenol, 3 -Aminothiophenol, 4-aminothiophenol residues, and some of the hydrogen atoms of these aromatic rings and hydrocarbons are substituted with alkyl groups having 1 to 10 carbon atoms, fluoroalkyl groups, halogen atoms, etc. Examples include, but are not limited to, residues of compounds and the like. Moreover, the polyimide of the present invention may contain two or more of these monoamine residues.

The introduction ratio of the terminal blocking agent to the polyimide terminal is in the range of 0.1 to 60 mol% with respect to the total amine component when converted to the primary monoamine component of the terminal blocking agent, which is the original component. It is preferably 5 to 50 mol %, more preferably 5 to 50 mol %.

Furthermore, in order to improve the adhesiveness to substrates when used for semiconductor elements or circuit boards, an aliphatic compound having a siloxane structure in R ₁ and R ₂ in the formula (3) is used within a range that does not reduce the heat resistance. The groups may be copolymerized. Specific examples of the diamine component include those obtained by copolymerizing 1 to 10 mol % of bis(3-aminopropyl)tetramethyldisiloxane, bis(p-amino-phenyl)octamethylpentasiloxane, or the like.

The polyimide of the present invention preferably has a weight average molecular weight of 1,000 or more and 200,000 or less, more preferably 5,000 or more and 100,000 or less, and 10,000 or more and 50,000 or less. is more preferred. Within this range, good workability, mechanical properties, and heat resistance can be obtained. The weight average molecular weight is measured by a gel permeation chromatography method (GPC method) and calculated in terms of polystyrene.

The polyimide of the present invention is preferably solvent-soluble. Alkali-soluble is particularly preferred. The solvent-soluble resin as used herein refers to a resin that dissolves at 25° C. in an amount of 0.1 g or more in 100 g of an organic solvent or an alkaline aqueous solution.

Organic solvents include γ-butyrolactone, γ-valerolactone, δ-valerolactone, dimethylsulfoxide, tetrahydrofuran, dioxane, propylene glycol monomethyl ether, propylene glycol monoethyl ether, acetone, methyl ethyl ketone, cyclopentanone, cyclohexanone, ethyl acetate, Butyl acetate, isobutyl acetate, propyl acetate, propylene glycol monomethyl ether acetate, 3-methyl-3-methoxybutyl acetate, methyl lactate, ethyl lactate, diacetone alcohol, 3-methyl-3-methoxybutanol, toluene, xylene, N- methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, N,N'-dimethylpropylene urea, 1 ,3-dimethylisobutyramide, methoxy-N,N-dimethylpropionamide, butoxy-N,N-dimethylpropionamide and the like.

Examples of alkaline aqueous solutions include tetramethylammonium hydroxide (TMAH), diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, diethylamine, methylamine, dimethylamine, dimethylaminoethyl acetate, dimethylamino Aqueous solutions of ethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine, hexamethylenediamine and the like can be mentioned.

When the polyimide is solvent-soluble, it is preferable in that a photosensitive resin composition using a polyimide solution in which the polyimide is dissolved can be developed, and from the viewpoint that an alkaline solution can be used as a developer, it is particularly alkali-soluble. Preferably. In order to exhibit solvent solubility, the polyimide of the present invention preferably has a hydroxyl group, a sulfonic acid group, a thiol group, or an organic group having 1 to 20 carbon atoms as described above, and the dissolution rate in an alkaline aqueous solution as a developer is A hydroxyl group is particularly preferable from the viewpoint that it becomes larger, the dissolution contrast between the cured portion and the uncured portion of the resin composition coating film increases, and fine pattern workability can be easily obtained.

The polyimide of the present invention preferably has a light transmittance of 90% or more, more preferably 95% or more, and even more preferably 99% or more at a wavelength of 365 nm per 1 μm film thickness. Within this range, fine pattern workability can be expressed even in a thick film of 20 μm or more when the photosensitive resin composition is formed.

In addition, the polyimide of the present invention has a yellowness in the range of 0 to 3.0. If the yellowness is out of this range, the transparency will be impaired and the appearance will be poor, making it unsuitable for use in semiconductor devices and circuit boards. The yellowness referred to here means that a polyimide solution in which polyimide is dissolved in an organic solvent is applied onto a substrate, and the solvent is removed by drying to prepare a polyimide film, and the obtained film is measured by a C light source color meter. Indicates a value calculated by measurement. The yellowness index preferably ranges from 0 to 2.8, more preferably from 0 to 2.5. By using a tetracarboxylic dianhydride (a) with a purity of 98% by mass or more and a diamine (b) with a purity of 98% by mass or more, a polyimide having a yellowness within this range can be obtained.

In addition, the polyimide of the present invention has an organic solvent content of 1% by mass or less and does not substantially contain an organic solvent. The content is preferably 0.1% by mass or less, and more preferably 0% by mass. Here, 0% by mass means that the organic solvent is not contained at all. When the content of the organic solvent in the polyimide is within the above range, the safety to the human body derived from the organic solvent during handling increases.

The content of organic solvents can be calculated by high-performance liquid chromatography, gas chromatography, and measuring the total organic carbon concentration (TOC). For example, in TOC measurement, water-soluble components are extracted from polyimide obtained by polymerization using distilled water, and the concentration of extracted organic carbon is measured to calculate the content of organic solvent in the sample.

The polyimide resin composition of the present invention contains the polyimide represented by the formula (2), a photosensitizer and a solvent.

As the photosensitizer, a photoacid generator, a photobase generator, a photopolymerization initiator, etc. can be used. When a photoacid generator is used, an acid is generated in the light-irradiated portion of the resin composition, and the solubility of the light-irradiated portion in an alkaline developer increases, so that a positive pattern in which the light-irradiated portion dissolves is obtained. be able to. When a photopolymerization initiator is used, radicals are generated in the light-irradiated portion of the resin composition, radical polymerization proceeds, and the resin composition becomes insoluble in an alkaline developer, thereby forming a negative pattern. . In addition, UV curing during exposure is accelerated, and sensitivity can be improved.

A quinonediazide compound can be exemplified as the photoacid generator, and a compound in which a sulfonic acid of naphthoquinonediazide is bonded to a compound having a phenolic hydroxyl group via an ester is preferable. Examples of compounds having a phenolic hydroxyl group used here include Bis-Z, BisOC-Z, BisOPP-Z, BisP-CP, Bis26X-Z, BisOTBP-Z, BisOCHP-Z, BisOCR-CP, and BisP-MZ. , BisP-EZ, Bis26X-CP, BisP-PZ, BisP-IPZ, BisCR-IPZ, BisOCP-IPZ, BisOIPP-CP, Bis26X-IPZ, BisOTBP-CP, TekP-4HBPA (tetrakis P-DO-BPA), TrisP -HAP, TrisP-PA, BisOFP-Z, BisRS-2P, BisPG-26X, BisRS-3P, BisOC-OCHP, BisPC-OCHP, Bis25X-OCHP, Bis26X-OCHP, BisOCHP-OC, Bis236T-OCHP, methylene tris- FR-CR, BisRS-26X, BisRS-OCHP (trade names, manufactured by Honshu Chemical Industry Co., Ltd.), BIR-OC, BIP-PC, BIR-PC, BIR-PTBP, BIR-PCHP, BIP-BIOC- F, 4PC, BIR-BIPC-F, TEP-BIP-A (trade names, manufactured by Asahi Organic Chemicals Industry Co., Ltd.), 4,4'-sulfonyldiphenol (manufactured by Wako Pure Chemical Industries, Ltd.), BPFL (trade name, manufactured by JFE Chemical Co., Ltd.) can be mentioned. Preferable examples are those obtained by introducing 4-naphthoquinonediazide sulfonic acid or 5-naphthoquinone diazide sulfonic acid into these compounds having a phenolic hydroxyl group via an ester bond, and compounds other than these can also be used.

Photopolymerization initiators include compounds containing polymerizable unsaturated functional groups. Examples include unsaturated triple bond functional groups such as propargyl, and among these, conjugated vinyl groups, acryloyl groups, and methacryloyl groups are preferred from the standpoint of polymerizability. The number of functional groups contained is preferably 1 to 4 from the standpoint of stability, and the groups do not have to be the same. Further, the compound referred to herein means one having a molecular weight of 30-800. Specifically, for example, benzophenones such as benzophenone, Michler's ketone, 4,4,-bis(diethylamino)benzophenone, 3,3,4,4,-tetra(t-butylperoxycarbonyl)benzophenone, and 3,5- benzylidenes such as bis(diethylaminobenzylidene)-N-methyl-4-piperidone, 3,5-bis(diethylaminobenzylidene)-N-ethyl-4-piperidone, 7-diethylamino-3-thenonylcoumarin, 4,6- dimethyl-3-ethylaminocoumarin, 3,3-carbonylbis(7-diethylaminocoumarin), 7-diethylamino-3-(1-methylmethylbenzimidazolyl)coumarin, 3-(2-benzothiazolyl)-7-diethylaminocoumarin, etc. coumarins, anthraquinones such as 2-t-butylanthraquinone, 2-ethylanthraquinone, 1,2-benzanthraquinone, benzoins such as benzoin methyl ether, benzoin ethyl ether, and benzoin isopropyl ether, 2,4-dimethylthioxanthone, 2 Thioxanthones such as ,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-isopropylthioxanthone, ethylene glycol di(3-mercaptopropionate), 2-mercaptobenzthiazole, 2-mercaptobenzoxazole, 2-mercapto mercaptos such as benzimidazole, glycines such as N-phenylglycine, N-methyl-N-phenylglycine, N-ethyl-N-(p-chlorophenyl)glycine, N-(4-cyanophenyl)glycine, 1- Phenyl-1,2-butanedione-2-(o-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione-2-(o-methoxycarbonyl)oxime, 1-phenyl-1,2-propanedione- 2-(o-ethoxycarbonyl) oxime, 1-phenyl-1,2-propanedione-2-(o-benzoyl) oxime, bis(α-isonitrosopropiophenone oxime) isophthal, 1,2-octanedione, 1-[4-(phenylthio)phenyl]-, 2-(o-benzoyloxime) and other oximes, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1,2- α-aminoalkylphenones such as methyl-1[4-(methylthio)phenyl]-2-morifolinopropan-1-one, 2,2′-bis(o-chlorophenyl)-4,4′,5, 5′-tetraphenylbiimidazole and the like. These are used alone or in combination of two or more.

The content of the photosensitizer is not particularly limited, but is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and 0.7 parts by mass with respect to 100 parts by mass of the polyimide in the resin composition. The above is more preferable, and 1 part by mass or more is particularly preferable. When the content of the photosensitive agent is within the above range, the sensitivity during exposure, which will be described later, can be improved. On the other hand, the content of the photosensitive agent is preferably 25 parts by mass or less, more preferably 20 parts by mass or less, still more preferably 17 parts by mass or less, with respect to 100 parts by mass of the polyimide in the resin composition. Especially preferred. The resolution after development can be improved as content of a photosensitive agent is in the said range.

Solvents contained in the polyimide resin composition of the present invention include, for example, γ-butyrolactone, γ-valerolactone, δ-valerolactone, dimethylsulfoxide, tetrahydrofuran, dioxane, propylene glycol monomethyl ether, propylene glycol monoethyl ether, acetone, methyl ethyl ketone. , cyclopentanone, cyclohexanone, ethyl acetate, butyl acetate, isobutyl acetate, propyl acetate, propylene glycol monomethyl ether acetate, 3-methyl-3-methoxybutyl acetate, methyl lactate, ethyl lactate, diacetone alcohol, 3-methyl-3 -methoxybutanol, toluene, xylene, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, N,N-dimethylformamide, N,N-dimethylacetamide, 1,3-dimethyl-2-imidazolidinone, N,N'-dimethylpropylene urea, 1,3-dimethylisobutyramide, methoxy-N,N-dimethylpropionamide, butoxy-N,N-dimethylpropionamide, dimethylsulfoxide, and the like, but are not limited to these.

It is preferable not to use solvents that pose health or environmental concerns, specifically solvents that are subject to regulations in each country such as REACH regulations, N-methyl-2-pyrrolidone, N,N-dimethylformamide, For example, N,N-dimethylacetamide is not used.

As a result, since the polyimide of the present invention does not substantially contain an organic solvent, the polyimide resin composition of the present invention contains 0% by mass of solvents that pose health and environmental concerns that are subject to regulations in various countries such as REACH regulations. be. Here, 0% by mass means that no organic solvent is contained.

In addition, although the content of the solvent is not particularly limited, it is preferably 100 parts by mass or more and 10,000 parts by mass or less, more preferably 100 parts by mass or more and 5,000 parts by mass or less, relative to 100 parts by mass of the polyimide in the resin composition. 100 parts by mass or more and 2,000 parts by mass or less is particularly preferable. By setting the content of the solvent within the above range, it is preferable in terms of being able to form a coating film having a thickness of 1 μm or more with excellent coatability and flatness of the coating film.

The polyimide resin composition of the present invention can also contain additives such as cross-linking agents, cross-linking accelerators, sensitizers, dissolution modifiers, surfactants, stabilizers and antifoaming agents, if necessary.

The cured product of the present invention is a cured product obtained by curing the polyimide resin composition.

The method for obtaining the cured product of the present invention includes the steps of applying a polyimide resin composition on a substrate and drying to form a polyimide resin film on the substrate, exposing the photosensitive resin film, and the polyimide A method including a step of removing an unexposed portion of the resin film with a developer and developing the film, and a step of heat-treating the polyimide resin film after the development to obtain a cured product can be exemplified.

The step of applying the polyimide resin composition onto a substrate and drying to form a polyimide resin film on the substrate includes, for example, applying the polyimide resin composition to a spin coater, a spray coater, a screen coater, a blade coater, and a die coater. , calendar coater, meniscus coater, bar coater, roll coater, comma roll coater, gravure coater, slit die coater, etc., and dried at a temperature of 50 ° C or higher and 150 ° C or lower for 1 minute or more and several hours or less. Polyimide Examples include, but are not limited to, a step of forming a resin film.

In the step of exposing the photosensitive polyimide resin film, for example, through a mask having a desired pattern, 365 nm i-line, 405 nm h-line, and 432 nm g-line of a high pressure mercury lamp are exposed at 50 mJ or more and 3,000 mJ or less. but not limited to this. The polyimide resin film exposed by the above process may be baked after exposure. Post-exposure baking is preferably performed at 50° C. or higher from the viewpoint of curability and adhesion to the substrate, and preferably at 150° C. or lower from the viewpoint of resolution.

The step of removing the unexposed portion of the polyimide resin film with a developer for development includes, for example, spraying the developer onto the surface of the polyimide resin film, heaping the developer onto the film surface, immersing the film in the developer, Alternatively, a process of immersing and applying ultrasonic waves may be mentioned, but is not limited to these. Developing conditions such as the developing time and the temperature of the developer in the developing step may be any conditions as long as the exposed portion can be removed and the pattern can be formed.

As a developer, when an alkali developer is used, an aqueous solution of tetramethylammonium, diethanolamine, diethylaminoethanol, sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, triethylamine, diethylamine, methylamine, dimethylamine, dimethylamino acetate. Aqueous solutions of alkaline compounds such as ethyl, dimethylaminoethanol, dimethylaminoethyl methacrylate, cyclohexylamine, ethylenediamine and hexamethylenediamine are preferred. When developing with an organic solvent, the developer at this time includes N-methyl-2-pyrrolidone, N-acetyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide, dimethylsulfoxide, hexa A mixed solution of a polar solvent such as methyl phosphortriamide alone or in combination with methanol, ethanol, isopropyl alcohol, xylene, water, methyl carbitol, ethyl carbitol, or the like can be used.

You may rinse with water after development. Also here, alcohols such as ethanol and isopropyl alcohol, and esters such as ethyl lactate and propylene glycol monomethyl ether acetate may be added to water for rinsing. If necessary, an alcohol such as ethanol or isopropyl alcohol, ethyl lactate, propylene glycol monomethyl ether acetate, or the like may be added to water for rinsing.

In the step of heat-treating the polyimide resin film after development to obtain a cured product, for example, the heat treatment is performed at a temperature of 150° C. or higher and 500° C. or lower for 5 minutes or more and 5 hours or less to advance the thermal cross-linking reaction. but not limited thereto. For the heat treatment, a method of selecting a temperature and increasing the temperature stepwise or a method of selecting a certain temperature range and increasing the temperature continuously can be selected. The former includes, for example, a method of heat-treating at 130° C. and 200° C. for 30 minutes each, but is not limited to this. The latter includes, but is not limited to, a method of linearly increasing the temperature from room temperature to 400° C. over 2 hours.

The present invention will be described below with reference to examples, but the present invention is not limited to these examples.

(1) Presence or Absence of Solvent-Insoluble Part 1 g of γ-butyrolactone was added to 10 mg of a sample, and the mixture was allowed to stand at room temperature for 5 hours with stirring, and then the presence or absence of an insoluble part was confirmed.

(2) Measurement of Organic Solvent Content in Polyimide 500 mL of distilled water was added to 5.00 g of a sample, stirred at 97° C. for 2 hours, filtered using a filter with a pore size of 0.45 μm, and the filtrate was collected. The total organic carbon concentration in the collected liquid was measured using a TOC (total organic carbon concentration) meter (TOC-Vwp; manufactured by Shimadzu Corporation) to calculate the total organic carbon concentration in the sample.

(3) Weight average molecular weight measurement Using a GPC (gel permeation chromatography) device (Waters 2690-996; manufactured by Nippon Waters Co., Ltd.), measurement was performed using tetrahydrofuran as a developing solvent, and the weight average molecular weight (Mw) was calculated in terms of polystyrene. bottom.

(4) Measurement of yellowness index (YI) A 39% γ-butyrolactone solution of polyimide was applied onto a glass substrate using a spin coater (1H-360S manufactured by Mikasa Co., Ltd.), followed by a hot plate (Dainippon Screen Co., Ltd.). ) manufactured by SCW-636) was prebaked at 120° C. for 3 minutes to form a thin film having a thickness of 10 μm. Using a C light source spectrophotometer (U2910 manufactured by Hitachi Ltd.), the degree of yellowness of the resulting polyimide thin film was measured.

(5) Evaluation of fine pattern processability of resin composition The resin composition was applied on a copper substrate using a spin coater (1H-360S manufactured by Mikasa Co., Ltd.), and a hot plate (SCW manufactured by Dainippon Screen Co., Ltd.) -636) and dried by heating at 100° C. for 3 minutes to form a coating film of 10 μm. Using an aligner (PLA-501F manufactured by Canon Inc.), a photomask having a pattern of L/S = 30 µm/30 µm, a pattern of 20 µm/20 µm, and a pattern of 15 µm/15 µm was formed on the copper substrate on which the coating film was formed. It was exposed to light at 200 mJ/cm ² using an ultra-high pressure mercury lamp as a light source. The exposure amount was calculated by measuring the illuminance at 365 nm. After that, it is heated at 120° C. for 1 minute, and an automatic processor (AD-1200 manufactured by Takizawa Sangyo Co., Ltd.) is used as a developer with a 2.38% by mass tetramethylammonium hydroxide (TMAH) aqueous solution as a developer for 45 seconds 2. It was developed with a paddle and rinsed with pure water for 30 seconds. Thereafter, the patterned portion was observed using an FPD microscope (MX61, manufactured by Olympus Corporation) to determine the minimum pattern size free from abnormalities such as development residues, and fine pattern processability was evaluated based on the following criteria. It was determined that the smaller the minimum pattern size, the better the pattern workability.
A: The minimum pattern size is 20 μm or less B: The minimum pattern size is 30 μm
C: A pattern of 30 μm cannot be processed, or a development residue is generated.

(6) After preparing the storage stability evaluation resin composition, the viscosity at 25 ° C. was measured using an E-type viscometer (TVE-25 manufactured by Toki Sangyo Co., Ltd.) after 12 hours, and the value was It was set to _V1 . After that, the resin composition was sealed and stored at room temperature (23° C.) for ₄ weeks. Storage stability was evaluated based on the following criteria, with the viscosity increase rate (%) being (V ₂ -V ₁ )/V ₁ ×100. It was determined that the smaller the viscosity increase rate, the better the storage stability.
A: Viscosity increase rate is less than 5% B: Viscosity increase rate is 5% or more and less than 10% C: Viscosity increase rate is 10% or more.

(7) Calculation of Raw Material Purity The purity of the sample was calculated using high performance liquid chromatography. Measurement conditions are shown below.
Apparatus: LC-10Avp series manufactured by Shimadzu Corporation Column: Mightysil RP-18 GP150-4.6 (5 μm)
Detector: Photodiode array detector (UV=270 nm).

Purity is the ratio of the peak area attributed to the main component in the sample to the peak area attributed to the sample-derived peak when the components are divided. Purity = main component weight / (main component weight + impurity weight ).
<raw materials>
In Examples 1 to 17 and Comparative Examples 1 to 6, the following raw materials whose purity was measured according to the above (7) were used for polyimide synthesis.
4,4'-oxydiphthalic anhydride purity 98% by mass (hereinafter referred to as ODPA-1)
4,4'-oxydiphthalic anhydride purity 95% by mass (hereinafter referred to as ODPA-2)
4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic dianhydride purity 99 mass% (hereinafter, TDA-1)
Bis (3,4-dicarboxyphenyl) sulfonic acid dianhydride purity 98% by mass (hereinafter, BCSA-1)
2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane purity 98 mass% (hereinafter, BAHF-1)
2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane purity 95 mass% (hereinafter, BAHF-2)
1,3-bis(3-aminopropyl)tetramethyldisiloxane purity 98% by mass (hereinafter, SiDA-1)
2-aminobenzoic acid purity 98% by mass (hereinafter, AA-1)
3-aminophenol purity 98% by mass (hereinafter, MAP-1)
3-aminophenol purity 94% by mass (hereinafter, MAP-2)
Aniline purity 98% by mass (hereinafter, A-1)
3-aniline sulfonic acid purity 99% by mass (hereinafter, AS-1)
3-aminobenzenethiol purity 99% by mass (hereinafter, AB-1)
The names of the compounds used in Examples and Comparative Examples are shown below.
<Solvent>
GBL: γ-butyrolactone EL: Ethyl lactate <photoinitiator>
OXE02: Irgacure OXE02 (manufactured by BASF Japan Ltd.)
<Radical polymerizable compound>
DCP-A: Light acrylate DCP-A (manufactured by Kyoeisha Chemical Co., Ltd.)
BP-6EM: Light ester BP-6EM (manufactured by Kyoeisha Chemical Co., Ltd.)
MOI-BP: Karenz MOI-BP (manufactured by Showa Denko K.K.)
<Crosslinking agent>
MW-100LM: NIKALAC MW-100LM (manufactured by Sanwa Chemical Co., Ltd.)
MX-270: NIKALAC MX-270 (manufactured by Sanwa Chemical Co., Ltd.)
<Adhesion improver>
KBM403 (manufactured by Shin-Etsu Chemical Co., Ltd.)
<Surfactant>
PF77: Polyflow No. 77 (manufactured by Kyoeisha Chemical Co., Ltd.).

[Example 1]
31.02 g (0.1 mol) of 4,4′-oxydiphthalic anhydride (ODPA-2) and 2,2-bis(3-amino-4-hydroxyphenyl)hexanone were placed in a stainless steel autoclave equipped with a stirrer. 36.63 g (0.1 mol) of fluoropropane (BAHF-1) and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 100° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.1 MPa in gauge pressure. After being held at 100° C. for 10 hours, it was allowed to cool to around room temperature. The resulting content was filtered using a filter paper with a pore size of 1 μm to recover the solid content. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P1). When P1 was measured by infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 6,000.

Further, the obtained P1 was placed in a heat dryer, and after a reduced pressure atmosphere (133 Pa), the temperature was raised to 180°C. After being held at 180° C. for 12 hours, it was allowed to cool to around room temperature to obtain polyimide (P1′). When P1′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The obtained P1′ was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, under a yellow light, 3.5 g of P1', 0.5 g of OXE02, 0.5 g of DCP-A, 1.5 g of BP-6EM, 0.5 g of MOI-BP, 50 of MW-100LM 1.0 g of % EL solution, 0.5 g of MX-270, 0.25 g of KBM403, 0.06 g of 5% EL solution of PF77, 2.1 g of GBL, and 2.6 g of EL are mixed, and the retained particle size is A resin composition was prepared by pressure filtration using a 1 μm filter. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 2]
31.02 g (0.1 mol) of ODPA-2, 30.03 g (0.082 mol) of BAHF-1 and 1,3-bis(3-aminopropyl)tetramethyl are placed in a stainless steel autoclave equipped with a stirrer. 1.24 g (0.005 mol) of disiloxane (SiDA-1), 2.73 (0.025 mol) of 3-aminophenol (MAP-1) and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 120° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.2 MPa in gauge pressure. After being held at 120° C. for 4 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P2). When P2 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 7,200.

The obtained P2 was placed in a heat dryer and heated to 220° C. under a nitrogen stream. After being held at 220° C. for 10 hours, it was allowed to cool to around room temperature to obtain polyimide (P2′). When P2′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P2' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P2' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 3]
A stainless steel autoclave equipped with a stirrer was charged with 31.02 g (0.1 mol) of ODPA-2, 32.96 g (0.09 mol) of BAHF-1, and 1.0 g of p-aminobenzoic acid (AA-1). 51 g (0.01 mol) and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 160° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.6 MPa in gauge pressure. After being held at 160° C. for 4 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P3). When P3 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 10,300.

Further, the obtained P3 was placed in a heat dryer, and after a reduced pressure atmosphere (133 Pa), the temperature was raised to 120°C. After being held at 120° C. for 24 hours, it was allowed to cool to around room temperature to obtain polyimide (P3′). When P3′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P3' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P3' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 4]
A stainless steel autoclave equipped with a stirrer was charged with 35.83 g (0.1 mol) of bis(3,4-dicarboxyphenyl)sulfonic dianhydride (BCSA-1) and 30.03 g (0.1 mol) of BAHF-1. 085 mol), 2.33 g (0.025 mol) of aniline (A-1), and 255 g of deionized water were charged. After the inside of the reaction vessel was replaced with nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 180° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 1.0 MPa in gauge pressure. After being held at 180° C. for 4 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P4). When P4 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 13,400.
Further, the obtained P4 was placed in a heat dryer, and after a reduced pressure atmosphere (133 Pa), the temperature was raised to 240°C. After being held at 240° C. for 5 hours, it was allowed to cool to around room temperature to obtain polyimide (P4′). When P4′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P4' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P4' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 5]
4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic dianhydride (TDA-1) was placed in a stainless steel autoclave equipped with a stirrer. 30.03 g (0.1 mol) of , 32.96 g (0.09 mol) of BAHF-1, 2.18 g (0.02 mol) of MAP-1, and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 150° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.5 MPa in gauge pressure. After being held at 150° C. for 4 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P5). When P5 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 11,000.
The obtained P5 was placed in a heat dryer and heated to 160° C. under a nitrogen stream. After being held at 160° C. for 12 hours, it was allowed to cool to around room temperature to obtain polyimide (P5′). When P5′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P5' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P5' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 6]
A stainless steel autoclave equipped with a stirrer was charged with 31.02 g (0.1 mol) of ODPA-2, 33.43 g (0.1 mol) of BAHF-1, and 255 g of deionized water. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 120° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.2 MPa in gauge pressure. After being held at 120° C. for 4 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P6). When P6 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 12,000.

The obtained P6 was placed in a heat dryer and heated to 180° C. under a nitrogen stream. After being held at 180° C. for 12 hours, it was allowed to cool to around room temperature to obtain polyimide (P6′). When P6′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P6' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P6' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 7]
31.02 g (0.1 mol) of ODPA-2, 28.41 g (0.085 mol) of BAHF-1, and 2.33 g (0.025 mol) of A-1 in a stainless steel autoclave equipped with a stirrer , 255 g of ion-exchanged water was charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 160° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.6 MPa in gauge pressure. After being held at 160° C. for 4 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P7). When P7 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 11,500.

The obtained P7 was placed in a heat dryer and heated to 180° C. under a nitrogen stream. After being held at 180° C. for 24 hours, it was allowed to cool to around room temperature to obtain polyimide (P7′). When P7′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P7' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P7' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 8]
31.02 g (0.1 mol) of ODPA-2, 28.41 g (0.085 mol) of BAHF-1, and 2.73 g (0.025 mol) of MAP-1 in a stainless steel autoclave equipped with a stirrer , 255 g of ion-exchanged water was charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 160° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.6 MPa in gauge pressure. After being held at 160° C. for 4 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P8). When P8 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 10,800.

The obtained P8 was placed in a heat dryer and heated to 180° C. under a nitrogen stream. After holding at 180° C. for 24 hours, it was allowed to cool to around room temperature to obtain polyimide (P8′). When P8′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P8' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P8' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 9]
31.02 g (0.1 mol) of ODPA-2, 28.41 g (0.085 mol) of BAHF-1, and 3-aniline sulfonic acid (AS-1) were placed in a stainless steel autoclave equipped with a stirrer. 33 g (0.025 mol) and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 160° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.6 MPa in gauge pressure. After being held at 160° C. for 4 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain a polyimide (P9). When P9 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 9,500.

The obtained P9 was placed in a heat dryer and heated to 180° C. under a nitrogen stream. After being held at 180° C. for 24 hours, it was allowed to cool to around room temperature to obtain polyimide (P9′). When P9′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P9' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P9' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 10]
31.02 g (0.1 mol) of ODPA, 28.41 g (0.085 mol) of BAHF-1, 3.13 g (AB-1) of 3-aminobenzenethiol (AB-1) were added to a stainless steel autoclave equipped with a stirrer. 0.025 mol) and 255 g of ion-exchanged water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 160° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.6 MPa in gauge pressure. After being held at 160° C. for 4 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P10). When P10 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 10,800.

Further, the obtained P10 was placed in a heat dryer and heated to 180° C. under a nitrogen stream. After holding at 180° C. for 24 hours, it was allowed to cool to around room temperature to obtain polyimide (P10′). When P10′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The obtained P10′ was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P10' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 11]
31.02 g (0.1 mol) of ODPA-2, 30.03 g (0.082 mol) of BAHF-1, and 1.24 g (0.005 mol) of SiDA-1 in a stainless steel autoclave equipped with a stirrer , 2.73 (0.025 mol) of MAP-1, 204 g of deionized water, and 51 g of methanol were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 120° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.3 MPa in gauge pressure. After being held at 120° C. for 4 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P11). When P11 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 7,000.

Further, the obtained P11 was placed in a heat dryer, and after a reduced pressure atmosphere (133 Pa), the temperature was raised to 180°C. After holding at 180° C. for 12 hours, it was allowed to cool to around room temperature to obtain polyimide (P11′). When P11′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The obtained P11′ was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P11' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 12]
A stainless steel autoclave equipped with a stirrer was charged with 31.02 g (0.1 mol) of ODPA-2, 36.63 g (0.1 mol) of BAHF-1, and 255 g of deionized water. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 80° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.0 MPa in gauge pressure. After being held at 80° C. for 10 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P12). When P12 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 4,000.

Further, the obtained P12 was placed in a heat dryer, and after a reduced pressure atmosphere (133 Pa), the temperature was raised to 180°C. After holding at 180° C. for 12 hours, it was allowed to cool to around room temperature to obtain polyimide (P12′). When P12′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P12' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P12' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Example 13]
31.02 g (0.1 mol) of ODPA-2, 30.03 g (0.082 mol) of BAHF-1, and 1.24 g (0.005 mol) of SiDA-1 in a stainless steel autoclave equipped with a stirrer , 2.73 (0.025 mol) of MAP-1 and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 100° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.0 MPa in gauge pressure. After being held at 100° C. for 5 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P13). When P13 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 5,7000.

Furthermore, after sealing the reaction vessel containing the remaining reactants under nitrogen gas at room temperature and normal pressure, the temperature was again raised from room temperature to 200°C while stirring at 150 rpm. The pressure in the reaction system at this stage was 1.5 MPa in gauge pressure. After being held at 200° C. for 2 hours, it was allowed to cool to around room temperature to obtain polyimide (P13′). When P13' was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm-1 and 1,377 cm-1. Moreover, the weight average molecular weight was 12,000. The obtained P13 was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P13' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Comparative Example 1]
31.02 g (0.1 mol) of ODPA-2, 30.03 g (0.082 mol) of BAHF-1, 1.24 g (0.082 mol) of BAHF-1, and 1.24 g (0 005 mol), 2.73 (0.025 mol) of MAP-1, and 255 g of deionized water. After the inside of the reaction vessel was replaced with nitrogen gas, the temperature was raised from room temperature to 30° C. while stirring at 150 rpm under normal pressure. After holding at 30° C. for 8 hours, the obtained content was filtered using a filter paper with a pore size of 1 μm to recover the solid content. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain a product (P14). When P15 was measured by infrared absorption spectrum, a broad peak was detected around 2,500 to 3,500 cm ⁻¹ , which was considered to be derived from a salt composed of tetracarboxylic acid and amine. Moreover, the weight average molecular weight was 400.

The obtained P14 was placed in a heat dryer and heated to 220° C. under a nitrogen stream. After holding at 220° C. for 24 hours, it was allowed to cool to around room temperature to obtain polyimide (P14′). When P14′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P14' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

It should be noted that the evaluation of (5) and (6) could not be carried out because an insoluble portion was generated when the resin composition was prepared.

[Comparative Example 2]
31.02 g (0.1 mol) of ODPA-2, 31.13 g (0.085 mol) of BAHF-1, and 1.24 g (0.005 mol) of SiDA-1 in a stainless steel autoclave equipped with a stirrer , 2.18 g (0.02 mol) of MAP-1, and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 260° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 2.0 MPa in gauge pressure. After being held at 260° C. for 4 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P15). When measured by P15 infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 23,500.

Further, the obtained P15 was placed in a heat dryer, and after a reduced pressure atmosphere (133 Pa), the temperature was raised to 180°C. After being held at 180° C. for 12 hours, it was allowed to cool to around room temperature to obtain polyimide (P15′). When P15′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The obtained P15′ was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P15' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Comparative Example 3]
Under a dry nitrogen stream, 30.03 g (0.082 mol) of BAHF-1, 1.24 g (0.05 mol) of SiDA-1, and 2.73 g of MAP-1 were added to 100 g of N-methyl-2-pyrrolidone. (0.025 mol) was dissolved. 31.02 g (0.1 mol) of ODPA-2 was added thereto together with 30 g of N-methyl-2-pyrrolidone, reacted at 20° C. for 1 hour, and then reacted at 50° C. for 4 hours. After that, the mixture was stirred at 180° C. for 5 hours. After stirring, the reaction solution was poured into 3 L of ion-exchanged water, and the precipitate was collected by filtration using a filter paper with a pore size of 1 μm. After the collected precipitate was washed with water three times, it was subjected to vacuum drying at 50° C. for 12 hours to obtain polyimide (P16). When P16 was measured by infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 13,100.

The obtained P16 was placed in a heat dryer and heated to 180° C. under a nitrogen stream. After holding at 180° C. for 12 hours, it was allowed to cool to around room temperature to obtain polyimide (P16′). When P16′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P16' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

Also, a resin composition was prepared in the same manner as in Example 1, except that P16' was used instead of P1'. The prepared resin composition was evaluated according to the evaluation methods (5) and (6) above.

[Comparative Example 4]
31.02 g (0.1 mol) of ODPA-2, 36.63 g (0.1 mol) of BAHF-1, 128 g of N-methyl-2-pyrrolidone, and deionized water in a stainless steel autoclave equipped with a stirrer. 127 g of was charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 180° C. while stirring at 150 rpm. The pressure in the reaction system at this stage was 0.5 MPa in gauge pressure. After being held at 180° C. for 4 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 50° C. for 12 hours to obtain a product (P17). When P17 was measured by infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 1,000.

The obtained P17 was placed in a heat dryer and heated to 220° C. under a nitrogen stream. After being kept at 220° C. for 24 hours, it was allowed to cool to around room temperature to obtain a polyimide (P17′). When P17′ was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . The resulting P17' was evaluated according to the evaluation methods (1), (2), (3) and (4) above.

It should be noted that the evaluation of (5) and (6) could not be carried out because an insoluble portion was generated when the resin composition was prepared.

Table 1 shows the evaluation results of Examples 1 to 13 and Comparative Examples 1 to 4.

[Example 14]
A stainless steel autoclave equipped with a stirrer was charged with ODPA-1 (31.02 g, 0.1 mol), BAHF-1 (36.63 g, 0.1 mol), and 255 g of deionized water. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 195° C. over about 1.5 hours while stirring at 150 rpm. The pressure in the reaction system at this stage was 1.5 MPa in gauge pressure. After being held at 195° C. for 4 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 80° C. for 12 hours to obtain polyimide (P18). When P18 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 27,500. The obtained P18 was evaluated according to the evaluation methods (2), (3) and (4) above.

[Example 15]
ODPA-1 (31.02 g, 0.1 mol), BAHF-1 (30.03 g, 0.082 mol), SiDA-1 (1.24 g, 0.005 mol) were placed in a stainless steel autoclave equipped with a stirrer. , MAP-1 (2.73 g, 0.025 mol), and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 210° C. over about 1.5 hours while stirring at 150 rpm. The pressure in the reaction system at this stage was 2.0 MPa in gauge pressure. After being held at 210° C. for 4 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 80° C. for 12 hours to obtain a polyimide (P19). When P19 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 29,300. The obtained P19 was evaluated according to the evaluation methods (2), (3) and (4) above.

[Example 16]
BCSA-1 (35.83 g, 0.1 mol), BAHF-1 (30.03 g, 0.085 mol), SiDA-1 (1.24 g, 0.005 mol) were placed in a stainless steel autoclave equipped with a stirrer. , aniline (purity 98% by weight) (2.33 g, 0.02 mol), and 255 g of ion-exchanged water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 230° C. over about 1.5 hours while stirring at 150 rpm. The pressure in the reaction system at this stage was 2.8 MPa in gauge pressure. After being held at 230° C. for 12 hours, it was allowed to cool to around room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 80° C. for 12 hours to obtain polyimide (P20). When P20 was measured by infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 32,400. The obtained P20 was evaluated according to the evaluation methods (2), (3) and (4) above.

[Example 17]
TDA-1 (30.03 g, 0.1 mol), BAHF-1 (32.96 g, 0.09 mol), MAP-1 (2.18 g, 0.02 mol) were placed in a stainless steel autoclave equipped with a stirrer. , and charged with 255 g of ion-exchanged water. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 190° C. over about 1.5 hours while stirring at 150 rpm. The pressure in the reaction system at this stage was 1.2 MPa in gauge pressure. After being held at 190° C. for 4 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 80° C. for 12 hours to obtain polyimide (P21). When P21 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 24,400. The obtained P21 was evaluated according to the evaluation methods (2), (3) and (4) above.

[Comparative Example 5]
Under dry nitrogen stream, BAHF-1 (30.03 g, 0.082 mol), SiDA-1 (1.24 g, 0.05 mol), MAP-1 (2.73 g, 0.025 mol) was added to N-methyl -Dissolved in 100 g of 2-pyrrolidone. ODPA-1 (31.02 g, 0.1 mol) was added thereto together with 30 g of N-methyl-2-pyrrolidone, reacted at 20° C. for 1 hour, and then reacted at 50° C. for 4 hours. After that, the mixture was stirred at 180° C. for 5 hours. After stirring, the reaction solution was poured into 3 L of ion-exchanged water, and the precipitate was collected by filtration using a filter paper with a pore size of 1 μm. After the collected precipitate was washed with water three times, it was subjected to vacuum drying at 80° C. for 12 hours to obtain polyimide (P22). When P22 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 28,800. The obtained P22 was evaluated according to the evaluation methods (2), (3) and (4) above.

[Comparative Example 6]
ODPA-2 (31.02 g, 0.1 mol), BAHF-2 (31.13 g, 0.085 mol), SiDA-1 (1.24 g, 0.005 mol) were placed in a stainless steel autoclave equipped with a stirrer. , MAP-2 (2.18 g, 0.02 mol), and 255 g of deionized water were charged. After the reaction vessel was sealed under nitrogen gas at room temperature and normal pressure, the temperature was raised from room temperature to 210° C. over about 1.5 hours while stirring at 150 rpm. The pressure in the reaction system at this stage was 2.8 MPa in gauge pressure. After being held at 230° C. for 4 hours, it was allowed to cool to near room temperature. The obtained contents were separated by filtration using filter paper with a pore size of 1 μm, and the solid content was recovered. The obtained solid content was subjected to vacuum drying at 80° C. for 12 hours to obtain polyimide (P23). When P23 was measured by an infrared absorption spectrum, absorption peaks of an imide structure due to polyimide were detected near 1,780 cm ⁻¹ and 1,377 cm ⁻¹ . Moreover, the weight average molecular weight was 29,300. The obtained P23 was evaluated according to the evaluation methods (2), (3) and (4) above.

Table 2 shows the evaluation results of Examples 14 to 17 and Comparative Examples 5 and 6.

A cured product obtained by curing a polyimide resin composition containing polyimide obtained by the present invention can be suitably used as an insulating film or a protective film constituting electronic parts. Furthermore, since it does not substantially contain solvents that pose health and environmental concerns, it can greatly contribute to the provision of sustainable industrial products.

Here, electronic components include active components having semiconductors such as transistors, diodes, integrated circuits (ICs) and memories, and passive components such as resistors, capacitors and inductors. The electronic components also include packages sealed for the purpose of improving the durability of these components, and modules in which a plurality of components are integrated. An electronic component using a semiconductor is also called a semiconductor device or a semiconductor package. Moreover, a touch sensor panel etc. are mentioned.

Specific examples of cured products in electronic components include passivation films for semiconductors, surface protective films for semiconductor elements or TFTs (Thin Film Transistors), and interlayer insulation between rewiring in multilayer wiring for high-density mounting of 2 to 10 layers. It is suitably used for applications such as interlayer insulating films such as films, interlayer insulating films for passive components such as thin film capacitors, piezoelectric elements, and signal filters, insulating films for touch panels, and protective films. Furthermore, the cured product of the present invention can be used for each member of an image display device such as an organic EL display and a liquid crystal display. It is suitably used for applications such as a planarizing layer, a wiring planarizing layer, a TFT protective layer, an electrode protective layer, a wiring protective layer, a gate insulating layer, a color filter, a black matrix, or a black column spacer. It is not limited to this, and can be used for various purposes.

Claims (15)

Tetracarboxylic acid and/or tetracarboxylic dianhydride (a) and diamine (b) are heated at 80° C. or higher in a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent. A method for producing a polyimide, comprising a step (1) of obtaining a polyimide by reaction in a temperature range of 250° C. or less, and a step (2) of chain extension of the obtained polyimide. 2. The method for producing a polyimide according to claim 1, wherein the chain extension step (2) is a solid state polymerization step (2a). 2. The method for producing polyimide according to claim 1, wherein said chain extension step (2) is step (2b) of obtaining polyimide by reacting at a temperature higher than said step (1). The method for producing a polyimide according to any one of claims 1 to 3, wherein in the step (1), the polyimide is obtained by reacting at a temperature range of 80°C or higher and 140°C or lower. 3. The method for producing a polyimide according to claim 2, wherein in the step (2a), the solid state polymerization is carried out in a temperature range of 80[deg.] C. or higher and 250[deg.] C. or lower. The method for producing a polyimide according to any one of claims 1 to 5, wherein the monoamine (c) is further reacted in the step (1). The tetracarboxylic acid and / or tetracarboxylic dianhydride (a) contains one or more selected from the group consisting of compounds represented by formula (1), according to any one of claims 1 to 6 method for producing polyimide.

(In formula (1), R ₅ and R ₁₂ each independently represent an oxygen atom, C(CH ₃ ) ₂ , C(CF ₃ ) ₂ or SO ₂ , R ₆ and R ₇ each independently , a hydrogen atom, a hydroxyl group, a sulfonic acid group or a thiol group, and R ₈ , R ₉ , R ₁₀ , R ₁₁ , R ₁₃ and R ₁₄ each independently represent a hydrogen atom, a hydroxyl group, a sulfonic acid group, a thiol group or Indicates an alkyl group having 1 to 6 carbon atoms.) In a reaction solvent containing 60 to 100% by mass of water with respect to 100% by mass of the total reaction solvent, a tetracarboxylic dianhydride (d) with a purity of 98% by mass or more and a diamine (e) with a purity of 98% by mass or more ) in a temperature range of 100° C. or higher and 370° C. or lower to obtain a polyimide (3). 9. The method for producing a polyimide according to claim 8, wherein in the step (3), a monoamine (f) having a purity of 97% by mass or more is further reacted. It has a structural unit represented by formula (2), has an organic solvent content of 1% by mass or less, has a yellowness of 0 to 3.0, and has a weight average molecular weight of 5,000 to 100,000. some polyimide.

(In formula (2), R ₁ represents a 4- to 14-valent organic group having 5 to 40 carbon atoms, R ₂ represents a 2- to 12-valent organic group having 5 to 40 carbon atoms, and R ₃ and R ₄ are Each independently represents a hydroxyl group, a sulfonic acid group, a thiol group or an organic group having 1 to 20 carbon atoms, and α and β each independently represents an integer from 0 to 10 satisfying α+β≧1.) 11. The polyimide according to claim 10, wherein the content of the organic solvent is 0.1% by mass or less. 12. Polyimide according to claim 10 or 11, which is alkali-soluble. 13. The polyimide according to any one of claims 10 to 12, wherein at least one main chain end of said polyimide comprises a structure blocked with a terminal blocking agent. A polyimide resin composition containing the polyimide according to any one of claims 10 to 13, a photosensitizer and a solvent. A cured product obtained by curing the polyimide resin composition according to claim 14 .