TW202031727A - Polyimide resin, polyimide varnish, and polyimide film - Google Patents

Abstract

A polyimide resin having structural units A derived from a tetracarboxylic dianhydride and structural units B derived from a diamine, wherein the structural units A include a structural unit (A-1) that is at least one structural unit selected from the group consisting of a structural unit (A-1-1) derived from a compound represented by formula (a-1-1) shown below and a structural unit (A-1-2) derived from a compound represented by formula (a-1-2) shown below, the structural units B include a structural unit (B-1) derived from a compound represented by formula (b-1) shown below and a structural unit (B-2) that is at least one structural unit selected from the group consisting of a structural unit (B-2-1) derived from a compound represented by formula (b-2-1) shown below, a structural unit (B-2-2) derived from a compound represented by formula (b-2-2) shown below, a structural unit (B-2-3) derived from a compound represented by formula (b-2-3) shown below, a structural unit (B-2-4) derived from a compound represented by formula (b-2-4) shown below, and a structural unit (B-2-5) derived from a compound represented by formula (b-2-5) shown below, and the proportion of the structural unit (B-1) among all the structural units B is at least 70 mol%. Also provided are a polyimide varnish and a polyimide film containing this polyimide resin.

(Each R in formula (b-2-2) independently represents a hydrogen atom, a fluorine atom or a methyl group, and in formula (b-2-4), each of R¹ to R⁴ independently represents a monovalent aliphatic group or a monovalent aromatic group, each of Z¹ and Z² independently represents a bivalent aliphatic group or a bivalent aromatic group, and r is a positive integer.)

Description

Polyimide resin, polyimide varnish and polyimide film

The present invention relates to polyimide resin, polyimide varnish and polyimide film.

With regard to polyimide resins, various applications in the fields of electrical and electronic parts have been explored. For example, in order to reduce the weight and flexibility of the device, it is hoped to replace the glass substrate used in image display devices such as liquid crystal displays and OLED displays with plastic substrates. Research on polyimide films suitable as plastic substrates is underway. get on. In an image display device, when the light emitted by the display element is emitted through a plastic substrate, the plastic substrate is required to have colorless transparency. In addition, when the light passes through a retardation film or a polarizing plate (for example, liquid crystal display, touch panel, etc.) In addition to requiring colorless transparency, it also requires high optical isotropy (that is, low Rth).

In order to meet the above-mentioned required performance, various polyimide resins have been developed. For example, in Patent Document 1, as a polyimide resin that provides a colorless, transparent, low Rth, and excellent toughness polyimide film, it is described that 3,3'-diaminodiphenylene oxide (the first diamine) is used Polyimide resin prepared by combining with a specific diamine (second diamine) such as 4,4'-diaminodiphenyl as the diamine component. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] International Publication No. 2016/158825

[The problem to be solved by the invention]

In order for the polyimide film to be suitable as a substrate, not only the colorless transparency and optical isotropy are important physical properties, but also chemical resistance (solvent resistance, acid resistance, and alkali resistance) are also important physical properties. For example, when the varnish for forming the resin layer is applied to the polyimide film in order to form another resin layer (for example, color filter, photoresist) on the polyimide film, the polyimide film is required It has resistance to the solvent contained in the varnish. If the solvent resistance of the polyimide film is insufficient, the dissolution and swelling of the film may cause it to no longer be meaningful as a substrate. In addition, when a polyimide film is used as a substrate for forming an ITO (Indium Tin Oxide) film, the polyimide film is required to have resistance to the acid used for etching of the ITO film. If the acid resistance of the polyimide film is insufficient, the film may turn yellow and impair the colorless transparency. In addition, for washing of supports such as glass plates used in the production of polyimide films (supports coated with polyimide varnish), alkaline aqueous solutions such as sodium hydroxide aqueous solution and potassium hydroxide aqueous solution are mainly used. Washing with an aqueous alkali solution can be performed even in a state where a polyimide film has been formed on a support such as a glass plate. Therefore, the polyimide film is also required to have alkali resistance. However, Patent Document 1 does not evaluate the chemical resistance.

The present invention is made in view of such a situation. The subject of the present invention is to provide a polyamide that can form a film with excellent colorless transparency, optical isotropy, and chemical resistance (solvent resistance, acid resistance, and alkali resistance). Amine resin, and polyimide varnish and polyimide film containing the polyimide resin. [Means to solve the problem]

The inventors of the present application found that a polyimide resin containing a combination of specific structural units can solve the above-mentioned problems, and completed the present invention.

式(b-2-2)中， R各自獨立地為氫原子、氟原子或甲基， 式(b-2-4)中， R¹ ～R⁴ 各自獨立地為一價脂肪族基或一價芳香族基， Z¹ 及Z² 各自獨立地為二價脂肪族基或二價芳香族基， r為正整數。That is, the present invention relates to the following [1] to [10]. [1] A polyimide resin having structural unit A derived from tetracarboxylic dianhydride and structural unit B derived from diamine; structural unit A contains structural unit (A-1), and structural unit (A-1) is Selected from the constituent unit (A-1-1) derived from the compound represented by the following formula (a-1-1) and the constituent unit (A-1-2) derived from the compound represented by the following formula (a-1-2) At least one of the group of; The structural unit B contains the structural unit (B-1) from the compound represented by the following formula (b-1) and the structural unit (B-2), and the structural unit (B-2) is Selected from the structural unit (B-2-1) derived from the compound represented by the following formula (b-2-1), the structural unit (B-2-2) derived from the compound represented by the following formula (b-2-2), The structural unit (B-2-3) derived from the compound represented by the following formula (b-2-3), the structural unit (B-2-4) derived from the compound represented by the following formula (b-2-4), and At least 1 of the group consisting of the structural unit (B-2-5) of the compound represented by the following formula (b-2-5); the ratio of the structural unit (B-1) in the structural unit B is 70 mol %the above. [化1]

In formula (b-2-2), R is each independently a hydrogen atom, a fluorine atom or a methyl group, and in formula (b-2-4), R ¹ to R ⁴ are each independently a monovalent aliphatic group or a monovalent aliphatic group For the aromatic group, Z ¹ and Z ² are each independently a divalent aliphatic group or a divalent aromatic group, and r is a positive integer.

[2] The polyimide resin of [1] above, wherein the ratio of the structural unit (B-1) in the structural unit B is 70-97 mol%, and the ratio of the structural unit (B-2) in the structural unit B It is 3-30 mole%. [3] The polyimide resin of [1] or [2] above, wherein the ratio of the structural unit (A-1) in the structural unit A is 50 mol% or more. [4] The polyimide resin according to any one of [1] to [3] above, wherein the structural unit (B-2) is the structural unit (B-2-1). [5] The polyimide resin of any one of [1] to [3] above, wherein the structural unit (B-2) is the structural unit (B-2-2). [6] The polyimide resin of any one of [1] to [3] above, wherein the structural unit (B-2) is the structural unit (B-2-3). [7] The polyimide resin according to any one of [1] to [3] above, wherein the structural unit (B-2) is the structural unit (B-2-4). [8] The polyimide resin according to any one of [1] to [3] above, wherein the structural unit (B-2) is the structural unit (B-2-5). [9] A polyimide varnish made by dissolving the polyimide resin of any one of [1] to [8] above in an organic solvent. [10] A polyimide film containing the polyimide resin as described in any one of [1] to [8] above. [Effects of Invention]

According to the present invention, a film excellent in colorless transparency, optical isotropy, and chemical resistance (solvent resistance, acid resistance, and alkali resistance) can be formed.

式(b-2-2)中， R各自獨立地為氫原子、氟原子或甲基， 式(b-2-4)中， R¹ ～R⁴ 各自獨立地為一價脂肪族基或一價芳香族基， Z¹ 及Z² 各自獨立地為二價脂肪族基或二價芳香族基， r為正整數。[Polyimine resin] The polyimide resin of the present invention has a structural unit A derived from tetracarboxylic dianhydride and a structural unit B derived from diamine, and the structural unit A contains the structural unit (A-1), and the structural unit (A-1) is selected from the structural unit (A-1-1) derived from the compound represented by the following formula (a-1-1) and the structural unit (A-1-1) derived from the compound represented by the following formula (a-1-2) -1-2) At least one of the constituent groups, the constituent unit B contains constituent unit (B-1) derived from the compound represented by the following formula (b-1), and constituent unit (B-2), constituent unit (B-2) is selected from the structural unit (B-2-1) derived from the compound represented by the following formula (b-2-1), the structural unit (B-2-1) derived from the compound represented by the following formula (b-2-2) -2-2), the structural unit (B-2-3) derived from the compound represented by the following formula (b-2-3), the structural unit (B-2) derived from the compound represented by the following formula (b-2-4) -4), and at least one of the group consisting of the structural unit (B-2-5) from the compound represented by the following formula (b-2-5), the structural unit (B-1) in the structural unit B The ratio is more than 70 mol%. [化2]

In formula (b-2-2), R is each independently a hydrogen atom, a fluorine atom or a methyl group, and in formula (b-2-4), R ¹ to R ⁴ are each independently a monovalent aliphatic group or a monovalent aliphatic group For the aromatic group, Z ¹ and Z ² are each independently a divalent aliphatic group or a divalent aromatic group, and r is a positive integer.

<Construction unit A> The constituent unit A is a constituent unit derived from tetracarboxylic dianhydride in the polyimide resin, and contains the constituent unit (A-1). The constituent unit (A-1) is selected from the following formula One of the structural unit (A-1-1) of the compound represented by (a-1-1) and the structural unit (A-1-2) from the compound represented by the following formula (a-1-2) At least one. [化3]

The compound represented by formula (a-1-1) is 1,2,4,5-cyclohexanetetracarboxylic dianhydride. Since the structural unit A contains the structural unit (A-1-1) as the structural unit (A-1), the colorless transparency and optical isotropy of the film can be improved.

The compound represented by formula (a-1-2) is 4,4'-oxydiphthalic anhydride. Since the structural unit A contains the structural unit (A-1-2) as the structural unit (A-1), the chemical resistance of the film can be improved.

The ratio of the constituent unit (A-1) in the constituent unit A is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 90 mol% or more, particularly preferably 99 mol% or more . The upper limit of the ratio of the structural unit (A-1) is not particularly limited, that is, it is 100 mol%. The constituent unit A may be composed of only the constituent unit (A-1).

The structural unit (A-1) may be only the structural unit (A-1-1), or may be only the structural unit (A-1-2). In addition, the structural unit (A-1) may be a combination of the structural unit (A-1-1) and the structural unit (A-1-2). When the structural unit (A-1) is a combination of the structural unit (A-1-1) and the structural unit (A-1-2), the structural unit (A-1-1)/the structural unit (A-1-2) In terms of molar ratio, the ratio is preferably 5/95～95/5. Considering colorless transparency, optical isotropy and chemical resistance, it is more preferably 20/80～90/10, and 50/50～ 90/10 is even better. In addition, considering the toughness of the obtained film, it is better to be 20/80～70/30, and especially considering improving the optical isotropy of the obtained film, 60/40～95/5 is particularly preferable. 70/30～95/5 is particularly good, and 85/15～95/5 is even better.

The structural unit A may contain structural units other than the structural unit (A-1). The tetracarboxylic dianhydride providing such a structural unit is not particularly limited, and examples thereof include: pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 9,9'-bis (3,4-Dicarboxyphenyl) dianhydride, and 4,4'-(hexafluoroisopropylene) diphthalic anhydride and other aromatic tetracarboxylic dianhydrides (except formula (a- 1-2) The compound represented); 1,2,3,4-cyclobutane tetracarboxylic dianhydride and norbornane-2-spiro-α-cyclopentanone-α'-spiro-2''-nor Alicyclic tetracarboxylic dianhydrides such as campane-5,5'',6,6''-tetracarboxylic dianhydride (except for compounds represented by formula (a-1-1)); and 1,2 , 3,4-butane tetracarboxylic dianhydride and other aliphatic tetracarboxylic dianhydrides. In addition, in this specification, aromatic tetracarboxylic dianhydride means tetracarboxylic dianhydride containing more than one aromatic ring, and alicyclic tetracarboxylic dianhydride refers to containing more than one alicyclic ring and no aromatic Cyclic tetracarboxylic dianhydride and aliphatic tetracarboxylic dianhydride mean tetracarboxylic dianhydride that does not contain an aromatic ring or an alicyclic ring. The structural unit arbitrarily contained in the structural unit A (that is, the structural unit other than the structural unit (A-1)) may be one type or two or more types.

式(b-2-2)中， R各自獨立地為氫原子、氟原子或甲基， 式(b-2-4)中， R¹ ～R⁴ 各自獨立地為一價脂肪族基或一價芳香族基， Z¹ 及Z² 各自獨立地為二價脂肪族基或二價芳香族基， r為正整數。<Constitutional unit B> The structural unit B is a structural unit derived from a diamine in the polyimide resin, and contains a structural unit (B-1) derived from a compound represented by the following formula (b-1), and a structural unit ( B-2), the structural unit (B-2) is selected from the structural unit (B-2-1) derived from the compound represented by the following formula (b-2-1), and represented by the following formula (b-2-2) The structural unit (B-2-2) of the compound, the structural unit (B-2-3) from the compound represented by the following formula (b-2-3), and the compound represented by the following formula (b-2-4) At least one of the group consisting of the structural unit (B-2-4) and the structural unit (B-2-5) from the compound represented by the following formula (b-2-5). [化4]

In formula (b-2-2), R is each independently a hydrogen atom, a fluorine atom or a methyl group, and in formula (b-2-4), R ¹ to R ⁴ are each independently a monovalent aliphatic group or a monovalent aliphatic group For the aromatic group, Z ¹ and Z ² are each independently a divalent aliphatic group or a divalent aromatic group, and r is a positive integer.

The compound represented by the formula (b-1) is 3,3'-diaminodiphenyl sulfide. The compound represented by the formula (b-2-1) is 4,4'-diamino-2,2'-bistrifluoromethyldiphenyl ether. Especially considering the toughness and acid resistance of the film, the structural unit (B-2) should preferably contain the structural unit (B-2-1) derived from the compound represented by formula (b-2-1), and the structural unit B should preferably contain (b-2-1) represents the structural unit (B-2-1) of the compound. In the formula (b-2-2), R is each independently a hydrogen atom, a fluorine atom, or a methyl group, and preferably a hydrogen atom. Examples of the compound represented by the formula (b-2-2) include 9,9-bis(4-aminophenyl)sulfuron, 9,9-bis(3-fluoro-4-aminophenyl)sulfuron, and 9,9-bis(3-methyl-4-aminophenyl)sulphur, etc., preferably 9,9-bis(4-aminophenyl)sulphur. In particular, considering the heat resistance and optical isotropy of the film, the structural unit (B-2) preferably contains the structural unit (B-2-2) derived from the compound represented by the formula (b-2-2), and the structural unit B is preferably It contains a structural unit (B-2-2) derived from the compound represented by formula (b-2-2). The compound represented by formula (b-2-3) is 2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane. Especially considering the colorlessness and transparency of the film, the structural unit (B-2) preferably contains the structural unit (B-2-3) derived from the compound represented by formula (b-2-3), and the structural unit B preferably contains the structural unit derived from the formula ( b-2-3) represents the structural unit (B-2-3) of the compound.

R ¹ , R ² , R ³ and R ^{4 in} formula (b-2-4) each independently represent a monovalent aliphatic group or a monovalent aromatic group, and these may also be substituted with a fluorine atom. The monovalent aliphatic group includes a monovalent saturated hydrocarbon group or a monovalent unsaturated hydrocarbon group. Examples of the monovalent saturated hydrocarbon group include alkyl groups having 1 to 22 carbon atoms, and examples include methyl, ethyl, and propyl. Examples of the monovalent unsaturated hydrocarbon group include alkenyl groups having 2 to 22 carbon atoms, and examples thereof include vinyl groups and propenyl groups. Examples of the monovalent aromatic group include aryl groups and aralkyl groups having 6 to 24 carbon atoms. R ¹ , R ² , R ³ and R ⁴ are particularly preferably methyl or phenyl. In addition, Z ¹ and Z ² each independently represent a divalent aliphatic group or a divalent aromatic group, and these groups may be substituted with a fluorine atom or may contain an oxygen atom. When an oxygen atom is contained as an ether bond, the number of carbons shown below refers to the total number of carbons contained in the aliphatic group or aromatic group. The divalent aliphatic group includes a divalent saturated hydrocarbon group or a divalent unsaturated hydrocarbon group. Examples of the divalent saturated hydrocarbon group include alkylene groups and alkyleneoxy groups having 1 to 22 carbon atoms, and examples of alkylene groups include methylene, ethylene, and propylene. Examples of the divalent unsaturated hydrocarbon group include unsaturated hydrocarbon groups having 2 to 22 carbon atoms. Examples include vinylene groups, propylene groups, and alkylene groups having an unsaturated double bond at the end. Examples of alkyleneoxy groups include alkylene groups. Propyloxy, trimethyleneoxy and the like. Examples of the divalent aromatic group include phenylene having 6 to 24 carbon atoms, phenylene substituted with alkyl, and aralkylene. Z ¹ and Z ² are particularly preferably propylidene, phenylene and aralkylene. Moreover, r represents a positive integer, and is preferably an integer of 10 to 10,000.

Examples of the compound represented by the formula (b-2-4) include: 1,3-bis(3-aminopropyl)-1,1,2,2-tetramethyldisiloxane, 1,3- Bis(3-aminobutyl)-1,1,2,2-tetramethyldisiloxane, bis(4-aminophenoxy)dimethylsiloxane, 1,3-bis(4-amine Phenyloxy) tetramethyldisiloxane, 1,1,3,3-tetramethyl-1,3-bis(4-aminophenyl)disiloxane, 1,1,3,3 -Tetraphenoxy-1,3-bis(2-aminoethyl)disiloxane, 1,1,3,3-tetraphenyl-1,3-bis(2-aminoethyl)di Siloxane, 1,1,3,3-tetraphenyl-1,3-bis(3-aminopropyl)disiloxane, 1,1,3,3-tetramethyl-1,3- Bis(2-aminoethyl)disiloxane, 1,1,3,3-tetramethyl-1,3-bis(3-aminopropyl)disiloxane, 1,1,3, 3-Tetramethyl-1,3-bis(4-aminobutyl)disiloxane, 1,3-dimethyl-1,3-dimethoxy-1,3-bis(4-amine Butyl) disiloxane, 1,1,3,3,5,5-hexamethyl-1,5-bis(4-aminophenyl)trisiloxane, 1,1,5,5 -Tetraphenyl-3,3-dimethyl-1,5-bis(3-aminopropyl)trisiloxane, 1,1,5,5-tetraphenyl-3,3-dimethoxy 1,5-bis(4-aminobutyl)trisiloxane, 1,1,5,5-tetraphenyl-3,3-dimethoxy-1,5-bis(5-amine Pentyl) trisiloxane, 1,1,5,5-tetramethyl-3,3-dimethoxy-1,5-bis(2-aminoethyl)trisiloxane, 1, 1,5,5-tetramethyl-3,3-dimethoxy-1,5-bis(4-aminobutyl)trisiloxane, 1,1,5,5-tetramethyl-3 ,3-Dimethoxy-1,5-bis(5-aminopentyl)trisiloxane, 1,1,3,3,5,5-hexamethyl-1,5-bis(3- Aminopropyl) trisiloxane, 1,1,3,3,5,5-hexaethyl-1,5-bis(3-aminopropyl)trisiloxane, 1,1,3, 3,5,5-hexapropyl-1,5-bis(3-aminopropyl)trisiloxane etc. The above-mentioned compounds can be used alone or in combination of two or more kinds. Commercially available products of the compound represented by the formula (b-2-4) include "X-22-9409", "X-22-1660B", and "X- 22-161A", "X-22-161B", etc. Especially considering the acid resistance and transparency of the film, the structural unit (B-2) should preferably contain the structural unit (B-2-4) derived from the compound represented by formula (b-2-4), and the structural unit B should preferably contain The structural unit (B-2-4) of the compound represented by the formula (b-2-4).

The compound represented by the formula (b-2-5) is 2,2'-bis(trifluoromethyl)benzidine. In particular, considering the toughness, heat resistance and optical isotropy of the film, the structural unit (B-2) should preferably contain the structural unit (B-2-5) derived from the compound represented by the formula (b-2-5). B preferably contains the structural unit (B-2-5) derived from the compound represented by the formula (b-2-5).

As mentioned above, considering the improvement of the various properties of the film, the structural unit B preferably contains the structural unit (B-2-1) selected from the compound represented by the formula (b-2-1) and the formula (b-2-2) The structural unit (B-2-2) of the compound represented, the structural unit (B-2-3) derived from the compound represented by the formula (b-2-3), the compound derived from the compound represented by the formula (b-2-4) The structural unit (B-2-4) and at least one of the group consisting of the structural unit (B-2-5) from the compound represented by the formula (b-2-5) is used as the structural unit (B-2) In particular, from the viewpoint of improving the colorless transparency and optical isotropy of the film, the structural unit B preferably contains the structural unit (B-2-3) derived from the compound represented by the formula (b-2-3).

Since the structural unit B contains both the structural unit (B-1) and the structural unit (B-2), and the ratio of the structural unit (B-1) in the structural unit B is set to 70 mol% or more, it can be Improve the colorless transparency, optical isotropy, and chemical resistance of the film. Among them, it can especially improve acid resistance and solvent resistance.

The ratio of the constituent unit (B-1) in the constituent unit B is 70 mol% or more. Considering the viewpoint of acid resistance and solvent resistance, the ratio is preferably 70-97 mol%, more preferably 75-97 mol%, and still more preferably 80-97 mol%, considering the viewpoint of acid resistance, it is more It is preferably 90-97 mol%, and particularly preferably 93-97 mol%. The ratio of the constituent unit (B-2) in the constituent unit B is preferably 3-30 mol%, more preferably 3-25 mol%, and still more preferably 3-20 mol%. Especially the structural unit (B-2) is selected from the group consisting of structural units (B-2-1), (B-2-2), (B-2-3) and (B-2-5) When there is at least one, the ratio of the constituent unit (B-2) is more preferably 10-25 mol%, and still more preferably 10-20 mol%. Moreover, especially when the structural unit (B-2) is the structural unit (B-2-4), the ratio of the structural unit (B-2) is particularly preferably 3-15 mol%, and more preferably 3-10 mol% %, and particularly preferably 3-7 mole%. The total ratio of the constituent units (B-1) and (B-2) in the constituent unit B is preferably 75 mol% or more, more preferably 80 mol% or more, and even more preferably 90 mol% or more. Preferably, it is 99 mol% or more. The upper limit of the total ratio of the constituent units (B-1) and (B-2) is not particularly limited, and it is 100 mol%. The structural unit B may be composed of only the structural unit (B-1) and the structural unit (B-2).

The structural unit (B-2) may be only the structural unit (B-2-1), or only the structural unit (B-2-2), or only the structural unit (B-2-3), or Only the structural unit (B-2-4), or only the structural unit (B-2-5). In addition, the structural unit (B-2) may be a combination of two or more structural units selected from the group consisting of the structural units (B-2-1) to (B-2-5).

The structural unit B may contain structural units other than the structural units (B-1) and (B-2). The diamine that provides such a structural unit is not particularly limited, and examples include 1,4-phenylenediamine, p-xylylene diamine, 3,5-diaminobenzoic acid, 1,5-diaminonaphthalene, 2,2'-Dimethylbiphenyl-4,4'-diamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 2,2-bis( 4-aminophenyl)hexafluoropropane, 4,4'-diaminodiphenyl sulfide, 4,4'-diaminophenylaniline, 1-(4-aminophenyl)-2,3 -Dihydro-1,3,3-trimethyl-1H-indene-5-amine, α,α'-bis(4-aminophenyl)-1,4-diisopropylbenzene, N,N' -Bis(4-aminophenyl)p-xylylenedimethamide, 4,4'-bis(4-aminophenoxy)biphenyl, and 2,2-bis[4-(4-aminobenzene) (Oxy)phenyl]propane and other aromatic diamines (except for the compounds represented by formula (b-1) and the compounds represented by formula (b-2-1)～(b-2-5)); 1, Alicyclic diamines such as 3-bis(aminomethyl)cyclohexane and 1,4-bis(aminomethyl)cyclohexane; and aliphatic diamines such as ethylenediamine and hexamethylenediamine (However, the compound represented by formula (b-2-4) is excluded). In addition, in this specification, aromatic diamine means a diamine containing more than one aromatic ring, alicyclic diamine means a diamine containing more than one alicyclic ring and no aromatic ring, aliphatic diamine It means a diamine that does not contain aromatic or alicyclic rings. The structural unit arbitrarily contained in the structural unit B (that is, structural units other than the structural units (B-1) and (B-2)) may be one type or two or more types.

The number average molecular weight of the polyimide resin of the present invention, considering the mechanical strength of the obtained polyimide film, is preferably 5,000 to 200,000. In addition, the number average molecular weight of the polyimide resin can be calculated, for example, from a standard polymethyl methacrylate (PMMA) conversion value obtained by gel filtration chromatography.

The polyimide resin of the present invention may also contain structures other than the polyimine chain (a structure in which the constituent unit A and the constituent unit B form an imine bond). Examples of structures other than the polyimine chain that can be contained in the polyimide resin include a structure containing an amide bond. The polyimine resin of the present invention preferably contains a polyimine chain (a structure in which the constituent unit A and the constituent unit B form an imine bond) as the main structure. Therefore, the ratio of the polyimide chain in the polyimide resin of the present invention is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 90% by mass or more, particularly preferably 99% by mass %the above.

By using the polyimide resin of the present invention, a film with excellent colorless transparency, optical isotropy, and chemical resistance can be formed. The ideal physical properties of the film are as follows. When a film with a thickness of 10 μm is made, the total light transmittance is preferably 88% or more, more preferably 88.5% or more, and still more preferably 89% or more. When a film with a thickness of 10 μm is formed, the yellow index (YI) is preferably 4.0 or less, more preferably 2.5 or less, and even more preferably 2.0 or less. When a film with a thickness of 10 μm is formed, b* is preferably 2.0 or less, more preferably 1.2 or less, and still more preferably 1.0 or less. When a film with a thickness of 10 μm is formed, the absolute value of the thickness retardation (Rth) is preferably 70 nm or less, more preferably 60 nm or less, and still more preferably 50 nm or less. When a film with a thickness of 10 μm is formed, the mixed acid ΔYI is preferably 1.5 or less, more preferably 1.3 or less, and still more preferably 1.0 or less. When a film with a thickness of 10 μm is formed, the mixed acid Δb* is preferably 0.8 or less, more preferably 0.6 or less, and still more preferably 0.5 or less. In addition, the mixed acid ΔYI and the mixed acid Δb* respectively mean the difference in YI and b* before and after immersion when the polyimide film is immersed in a mixture of phosphoric acid, nitric acid, and acetic acid. Specifically, the method described in the examples can be used Determination. The smaller the ΔYI and Δb*, the better the acid resistance. By using the polyimide resin of the present invention, a film with excellent chemical resistance can be formed, and it also exhibits excellent resistance to acids. Especially for mixed acid (for example, a mixed solution of 50-97% by mass of phosphoric acid, 1-20% by mass of nitric acid, 1-10% by mass of acetic acid, and 1-20% by mass of water, 63 to 87% by mass of phosphoric acid and 5 to 20% by mass of nitric acid are preferred. A mixed solution of 15% by mass, 3-7% by mass of acetic acid, and 5-15% by mass of water) exhibits excellent tolerance.

The film that can be formed by using the polyimide resin of the present invention has good mechanical properties and has the following ideal physical properties. The tensile strength is preferably 60 MPa or more, more preferably 70 MPa or more, and still more preferably 80 MPa or more. The tensile modulus of elasticity is preferably 2.0 GPa or more, more preferably 2.5 GPa or more, and still more preferably 3.0 GPa or more.

In addition, the film formed by using the polyimide resin of one aspect of the present invention has good heat resistance and has the following ideal physical properties. The glass transition temperature (Tg) is preferably 230°C or higher, more preferably 250°C or higher, and still more preferably 270°C or higher. In addition, the above-mentioned physical property values in the present invention can be specifically measured by the methods described in the examples.

[Manufacturing method of polyimide resin] The polyimide resin of the present invention can be obtained by combining a tetracarboxylic acid component containing a compound providing the above-mentioned structural unit (A-1) and a compound containing 70 mol% or more of the above-mentioned structural unit (B-1) And the diamine component which provides the compound of the said structural unit (B-2) reacts and manufactures.

As the compound providing the structural unit (A-1), a compound represented by the formula (a-1-1) and a compound represented by the formula (a-1-2) can be cited, but it is not limited to this, and in the range of providing the same structural unit It can also be its derivatives. Examples of the derivative include tetracarboxylic acid corresponding to the tetracarboxylic dianhydride represented by formula (a-1-1) and formula (a-1-2) and alkyl esters of the tetracarboxylic acid. The compound providing the constituent unit (A-1) is preferably a compound represented by formula (a-1-1) and formula (a-1-2) (that is, dianhydride).

The tetracarboxylic acid component preferably contains 50 mol% or more of the compound providing the constituent unit (A-1), more preferably 70 mol% or more, more preferably 90 mol% or more, particularly preferably 99 mol% Ear% or more. The upper limit of the content ratio of the compound providing the structural unit (A-1) is not particularly limited, and that is, it is 100 mol%. The tetracarboxylic acid component may be composed only of the compound providing the structural unit (A-1).

The compound providing the constituent unit (A-1) may only be the compound providing the constituent unit (A-1-1), or may only be the compound providing the constituent unit (A-1-2). In addition, the compound providing structural unit (A-1) may also be a combination of a compound providing structural unit (A-1-1) and a compound providing structural unit (A-1-2). When the compound providing the structural unit (A-1) is a combination of the compound providing the structural unit (A-1-1) and the compound providing the structural unit (A-1-2), the structural unit (A-1-1) is provided The content ratio of the compound/compound providing the constituent unit (A-1-2) is preferably 5/95～95/5 in molar ratio, considering colorless transparency, optical isotropy and chemical resistance. It is more preferably from 20/80 to 90/10, and even more preferably from 50/50 to 90/10. In addition, considering the toughness of the obtained film, it is better to be 20/80～70/30, and especially considering improving the optical isotropy of the obtained film, 60/40～95/5 is particularly preferable. 70/30～95/5 is particularly good, and 85/15～95/5 is even better.

The tetracarboxylic acid component may also contain a compound other than the compound providing the constituent unit (A-1). The compound may include the above-mentioned aromatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aliphatic tetracarboxylic dianhydride. Anhydrides, and their derivatives (tetracarboxylic acid, alkyl ester of tetracarboxylic acid, etc.). The compound arbitrarily contained in the tetracarboxylic acid component (that is, a compound other than the compound providing the structural unit (A-1)) may be one type or two or more types.

The compound providing the structural unit (B-1) may be a compound represented by the formula (b-1), but it is not limited to this, and it may be a derivative thereof within the scope of providing the same structural unit. Examples of the derivative include diisocyanates corresponding to the diamine represented by formula (b-1). The compound providing the constituent unit (B-1) is preferably a compound represented by formula (b-1) (that is, diamine). As the compound providing the structural unit (B-2), a compound represented by the formula (b-2-1), a compound represented by the formula (b-2-2), a compound represented by the formula (b-2-3), The compound represented by the formula (b-2-4) and the compound represented by the formula (b-2-5) are not limited thereto, and may be derivatives thereof within the range that can form the same structural unit. Examples of the derivative include diisocyanates corresponding to the diamines represented by formulas (b-2-1) to (b-2-5). The compound providing the structural unit (B-2) is preferably a compound represented by formula (b-2-1) to formula (b-2-5) (that is, diamine).

The diamine component contains more than 70 mol% of the compound providing the constituent unit (B-1). The diamine component preferably contains 70-97 mol% of the compound providing the constituent unit (B-1), more preferably 75-97 mol%, and more preferably 80-97 mol%, considering the acid resistance From a viewpoint, it is more preferable to contain 90-97 mol%, and it is more preferable to contain 93-97 mol%. The diamine component preferably contains 3-30 mol% of the compound providing the constituent unit (B-2), more preferably 3-25 mol%, and more preferably 3-20 mol%. In particular, the compound providing the constituent unit (B-2) is selected from the group consisting of the compound providing the constituent unit (B-2-1), the compound providing (B-2-2), the compound providing (B-2-3) and the When there is at least one of the group consisting of the compound of (B-2-5), the diamine component preferably contains 10-25 mol% of the compound providing the constituent unit (B-2), and more preferably contains 10 ~20 mol%. In addition, especially when the compound providing the structural unit (B-2) is a compound providing the structural unit (B-2-4), the diamine component preferably contains 3-15 mol% of the providing structural unit (B-2) The compound preferably contains 3-10 mole%, and more preferably contains 3-7 mole%. The total diamine component should preferably contain 75 mol% or more of the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2), more preferably 80 mol% or more, and more preferably 90% Mole% or more, particularly preferably 99 mole% or more. The upper limit of the total content ratio of the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2) is not particularly limited, and is 100 mol%. The diamine component may be composed of only the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2).

The compound providing the constituent unit (B-2) may only be the compound providing the constituent unit (B-2-1), or only the compound providing the constituent unit (B-2-2), or only the constituent unit The compound of (B-2-3) may only provide the compound of the constituent unit (B-2-4), or may only provide the compound of the constituent unit (B-2-5). In addition, the compound providing the structural unit (B-2) may also be a combination of two or more compounds selected from the group consisting of the compounds providing the structural unit (B-2-1) to (B-2-5) .

The diamine component may also contain compounds other than the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2). Examples of the compound include the above-mentioned aromatic diamine, alicyclic diamine, and aliphatic Diamines, and their derivatives (diisocyanates, etc.). The compound arbitrarily contained in the diamine component (that is, a compound other than the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2)) may be one type or two or more types.

In the present invention, the ratio of the added amount of the tetracarboxylic acid component and the diamine component used in the production of the polyimide resin is preferably 0.9 to 1.1 mol of the diamine component relative to 1 mol of the tetracarboxylic acid component .

Furthermore, in the present invention, in addition to the aforementioned tetracarboxylic acid component and diamine component, an end-capping agent may also be used in the production of the polyimide resin. The blocking agent is preferably monoamine or dicarboxylic acid. The amount of the capping agent introduced is preferably 0.0001 to 0.1 mol relative to 1 mol of the tetracarboxylic acid component, and particularly preferably 0.001 to 0.06 mol. As monoamine blocking agents, for example, recommended: methylamine, ethylamine, propylamine, butylamine, benzylamine, 4-methylbenzylamine, 4-ethylbenzylamine, 4-dodecylbenzylamine, 3- Methylbenzylamine, 3-ethylbenzylamine, aniline, 3-methylaniline, 4-methylaniline, etc. Among these, benzylamine and aniline can be preferably used. As the dicarboxylic acid-based end-capping agent, a dicarboxylic acid is preferable, and a part of the ring may be closed. For example, recommended: phthalic acid, phthalic anhydride, 4-chlorophthalic acid, tetrafluorophthalic acid, 2,3-benzophenone dicarboxylic acid, 3,4-benzophenone two Carboxylic acid, cyclopentane-1,2-dicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, etc. Among these, phthalic acid and phthalic anhydride can be preferably used.

The method of reacting the said tetracarboxylic acid component and a diamine component is not specifically limited, A well-known method can be used. Specific reaction methods include the following methods: (1) The tetracarboxylic acid component, the diamine component, and the reaction solvent are added to the reactor, and stirred at room temperature (about 20°C) to 80°C for 0.5 to After 30 hours, the temperature is raised and the imidization reaction is carried out; (2) After adding the diamine component and the reaction solvent to the reactor to dissolve, add the tetracarboxylic acid component, if necessary, at room temperature (about 20°C) ~ Stir at 80°C for 0.5-30 hours, then heat up and proceed to the imidization reaction; (3) Add the tetracarboxylic acid component, the diamine component, and the reaction solvent to the reactor, and immediately heat up and proceed to the imidization reaction.

The reaction solvent used in the production of the polyimide resin may be one that does not hinder the imidization reaction and can dissolve the polyimide produced. For example, aprotic solvents, phenol-based solvents, ether-based solvents, carbonate-based solvents, etc. can be cited.

Specific examples of aprotic solvents include: N,N-dimethylformamide, N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and N-methylcaprolactone Amine solvents such as amine, 1,3-dimethylimidazolidinone, and tetramethylurea; lactone solvents such as γ-butyrolactone and γ-valerolactone; hexamethylphosphamide, hexamethyl Phosphorus-containing amine-based solvents such as phosphine triamide; sulfur-containing solvents such as dimethyl sulfide, dimethyl sulfide, and cyclobutane; ketone-based solvents such as acetone, cyclohexanone, and methyl cyclohexanone; Amine solvents such as pyridine and pyridine; ester solvents such as acetic acid (2-methoxy-1-methylethyl), etc.

Specific examples of phenolic solvents include: phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2 ,6-xylenol, 3,4-xylenol, 3,5-xylenol, etc. Specific examples of ether solvents include: 1,2-dimethoxyethane, bis(2-methoxyethyl)ether, 1,2-bis(2-methoxyethoxy)ethane Alkane, bis[2-(2-methoxyethoxy)ethyl]ether, tetrahydrofuran, 1,4-dioxane, etc. In addition, specific examples of carbonate-based solvents include diethyl carbonate, methyl ethyl carbonate, ethylene carbonate, and propylene carbonate. Among the above-mentioned reaction solvents, an amide-based solvent or a lactone-based solvent is preferable. Moreover, the said reaction solvent can be used individually or in mixture of 2 or more types.

Regarding the imidization reaction, it is preferable to perform the reaction while removing water generated during production using a Dean-Stark apparatus. By performing such an operation, the degree of polymerization and the rate of imidization can be further improved.

In the above-mentioned imidation reaction, a well-known imidation catalyst can be used. Examples of the imidization catalyst include alkali catalysts and acid catalysts. Examples of alkali catalysts include pyridine, quinoline, isoquinoline, α-picoline, β-picoline, 2,4-lutidine, 2,6-lutidine, trimethylamine, Triethylamine, tripropylamine, tributylamine, triethylenediamine, imidazole, N,N-dimethylaniline, N,N-diethylaniline and other organic base catalysts; potassium hydroxide, sodium hydroxide, carbonic acid Potassium, sodium carbonate, potassium bicarbonate, sodium bicarbonate and other inorganic base catalysts. In addition, examples of acid catalysts include crotonic acid, acrylic acid, trans-3-hexenoic acid, cinnamic acid, benzoic acid, methylbenzoic acid, hydroxybenzoic acid, terephthalic acid, benzenesulfonic acid, and p-toluene. Sulfonic acid, naphthalenesulfonic acid, etc. The above-mentioned imidization catalyst can be used alone or in combination of two or more kinds. Among the above, considering the operability, it is preferable to use an alkali catalyst, an organic alkali catalyst is more preferable, and triethylamine is even more preferable, and a combination of triethylamine and triethylenediamine is particularly preferable.

The temperature of the imidization reaction is preferably 120 to 250°C, more preferably 160 to 200°C from the viewpoint of reaction rate and inhibition of gelation. In addition, the reaction time is preferably 0.5 to 10 hours after the start of the distillation of the produced water.

[Polyimide varnish] The polyimide varnish of the present invention is formed by dissolving the polyimide resin of the present invention in an organic solvent. That is, the polyimide varnish of the present invention contains the polyimide resin of the present invention and an organic solvent, and the polyimide resin is dissolved in the organic solvent. The organic solvent is not particularly limited as long as it can dissolve the polyimide resin. The reaction solvent used in the production of the polyimide resin is preferably used alone or in combination of two or more. The polyimide varnish of the present invention can be the polyimide solution itself obtained by dissolving the polyimide resin obtained by the polymerization method in the reaction solvent, or it can also be the polyimide solution further adding a diluting solvent. Winner.

The polyimide resin of the present invention has solvent solubility, so it can be made into a high-concentration varnish that is stable at room temperature. The polyimide varnish of the present invention preferably contains 5-40% by mass of the polyimide resin of the present invention, and more preferably contains 10-30% by mass. The viscosity of the polyimide varnish is preferably 1～200Pa･s, preferably 2～100Pa･s. The viscosity of the polyimide varnish is a value measured at 25°C using an E-type viscometer. In addition, the polyimide varnish of the present invention may also contain inorganic fillers, adhesion promoters, release agents, flame retardants, ultraviolet stabilizers, and interface materials within the range that does not impair the required characteristics of the polyimide film. Various additives such as active agent, leveling agent, defoamer, fluorescent whitening agent, crosslinking agent, polymerization initiator, sensitizer, etc. The manufacturing method of the polyimide varnish of this invention is not specifically limited, A well-known method can be used.

[Polyimide film] The polyimide film of the present invention contains the polyimide resin of the present invention. Therefore, the polyimide film of the present invention is excellent in colorless transparency, optical isotropy, and chemical resistance (solvent resistance, acid resistance, and alkali resistance). The ideal physical properties of the polyimide film of the present invention are as described above. The manufacturing method of the polyimide film of this invention is not specifically limited, A well-known method can be used. For example, the polyimide varnish of the present invention is coated on a smooth support such as a glass plate, metal plate, plastic, or formed into a film, and then heated to remove organic solvents such as a reaction solvent and a dilution solvent contained in the varnish Method and so on.

The coating method includes well-known coating methods such as spin coating, slit coating, and knife coating. Among them, slit coating can control the intermolecular alignment and improve chemical resistance, which is preferable from the viewpoint of workability. As a method of removing the organic solvent contained in the varnish by heating, it is suitable to evaporate the organic solvent at a temperature of 150°C or less to make it non-viscous, and then at a temperature above the boiling point of the organic solvent used (not particularly limited, preferably (200 to 500°C) for drying is preferred. Moreover, it is suitable to dry in an air environment or a nitrogen environment. The pressure of the dry environment may be any one of reduced pressure, normal pressure, and increased pressure. The method of peeling the polyimide film formed on the support from the support is not particularly limited. Examples include the laser peeling method and the method of using a sacrificial layer for peeling (pre-coating a release agent on the surface of the support method).

In addition, the polyimide film of the present invention can also be produced using a polyimide varnish obtained by dissolving polyimide acid in an organic solvent. The polyimide contained in the aforementioned polyimide varnish is the precursor of the polyimide resin of the present invention and contains a tetracarboxylic acid component that provides the compound of the above-mentioned structural unit (A-1), and contains 70 Mo The addition polymerization reaction product of the compound of the above-mentioned structural unit (B-1) and the diamine component which provides the compound of the above-mentioned structural unit (B-2) of ear% or more. The polyimide resin of the present invention can be obtained as the final product by subjecting the polyimide acid to imidization (dehydration and ring closure). The organic solvent contained in the aforementioned polyimide varnish can be the organic solvent contained in the polyimide varnish of the present invention. In the present invention, the polyamide varnish may be the polyamide solution itself obtained by the addition polymerization reaction of the tetracarboxylic acid component and the diamine component in the reaction solvent, or may also be the polyamide acid solution It is obtained by adding further dilution solvent.

The method of manufacturing a polyimide film using a polyamide varnish is not specifically limited, A well-known method can be used. For example, it can be obtained by coating a polyamide varnish on a smooth support such as a glass plate, metal plate, plastic or the like or forming it into a film, and removing organic solvents such as a reaction solvent and a dilution solvent contained in the varnish by heating. The polyamide film is prepared by heating the polyamide acid in the polyamide acid film to imidize the polyamide film. The heating temperature when drying the polyamic acid varnish to obtain the polyamic acid film is preferably 50 to 120°C. The heating temperature when the polyamide acid is imidized by heating is preferably 200 to 400°C. In addition, the method of imidization is not limited to thermal imidization, and chemical imidization may be used.

The thickness of the polyimide film of the present invention can be appropriately selected according to the application, etc., and is preferably 1 to 250 μm, more preferably 5 to 100 μm, and still more preferably 10 to 80 μm. With a thickness of 1 to 250μm, it can be used as a self-supporting film. The thickness of the polyimide film can be easily controlled by adjusting the solid content and viscosity of the polyimide varnish.

The polyimide film of the present invention can be ideally used as a film for various components such as color filters, flexible displays, semiconductor parts, and optical components. The polyimide film of the present invention is particularly ideally used as a substrate for image display devices such as liquid crystal displays and OLED displays. [Example]

Hereinafter, the present invention will be specifically explained using examples. However, the present invention is not limited to these embodiments.

In the examples and comparative examples, each physical property was measured by the method shown below. (1) Film thickness The film thickness was measured using a micrometer manufactured by Mitutoyo Co., Ltd. (2) Tensile strength, tensile modulus of elasticity The tensile strength and tensile modulus of elasticity were measured in accordance with JIS K7127: 1999 using a tensile testing machine "Strograph VG-1E" manufactured by Toyo Seiki Co., Ltd. The distance between the chucks is set to 50mm, the size of the test piece is set to 10mm×70mm, and the test speed is set to 20mm/min. (3) Glass transition temperature (Tg) Use the thermomechanical analysis device "TMA/SS6100" manufactured by Hitachi High-Tech Science Co., Ltd., in a tensile mode, with a sample size of 2mm×20mm, a load of 0.1N, and a heating rate Under the condition of 10°C/min, heat up to a temperature sufficient to remove the residual stress to remove the residual stress, and then cool to room temperature. Then, the elongation of the test piece was measured under the same conditions as the above-mentioned treatment for removing residual stress, and the temperature at which the inflection point of the elongation was observed was determined as the glass transition temperature. (4) Total light transmittance, yellow index (YI), b* total light transmittance, YI and b*, based on JIS K7105:1981 using the color-turbidity simultaneous tester manufactured by Nippon Denshoku Industries Co., Ltd. "COH400" is measured. (5) Thickness retardation (Rth) Thickness retardation (Rth) was measured using an ellipsometer "M-220" manufactured by JASCO Corporation. The value of the thickness retardation at a wavelength of 590 nm is measured. In addition, in terms of Rth, when the largest in-plane refractive index of the polyimide film is nx, the smallest is ny, the refractive index in the thickness direction is nz, and the film thickness is d, it is expressed by the following formula. Rth={[(nx+ny)/2]-nz}×d (6) Solvent resistance In the polyimide film formed on a glass plate, add the solvent at room temperature to confirm whether the surface of the film changes. In addition, propylene glycol monomethyl ether acetate (PGMEA) was used as a solvent. The evaluation criteria of solvent resistance are as follows. A: There is no change in the film surface. B: Slight cracks are generated on the film surface. C: Cracks occurred on the film surface, or the film surface was dissolved. (7) Acid resistance (mixed acid ΔYI and mixed acid Δb*) The polyimide film formed on a glass plate is heated to 40℃ with mixed acid (H ₃ PO ₄ (70% by mass) + HNO ₃ (10% by mass) ) + CH ₃ COOH (5 mass %) + H ₂ O (15 mass %) mixed solution) for 4 minutes, and then washed with water. After washing with water, the water was wiped off, and it was dried by heating at 240°C for 50 minutes on a hot plate. YI and b* were measured before and after the test, and their changes (ΔYI and Δb*) were determined. In addition, the YI measurement and the b* measurement here are performed in a state where the polyimide film is formed on a glass plate (the state of the glass plate + the polyimide film). (8) Alkali resistance The polyimide film formed on the glass plate was immersed in a potassium hydroxide aqueous solution with a concentration of 3% by mass for 5 minutes at room temperature, and then washed with water. After washing with water, check whether the film surface has changed. The evaluation criteria of alkali resistance are as follows. A: There is no change in the film surface. B: Slight cracks are generated on the film surface. C: Cracks occurred on the film surface, or the film surface was dissolved.

The tetracarboxylic acid component and diamine component used in Examples and Comparative Examples, and their abbreviations are as follows. ＜Tetracarboxylic acid component＞ HPMDA: 1,2,4,5-cyclohexanetetracarboxylic dianhydride (manufactured by Mitsubishi Gas Chemical Co., Ltd.; compound represented by formula (a-1-1)) ODPA: 4,4'-oxydiphthalic anhydride (manufactured by MANAC Co., Ltd.; compound represented by formula (a-1-2)) ＜Diamine component＞ 3,3'-DDS: 3,3'-diaminodiphenyl sulfide (manufactured by SEIKA Co., Ltd.; compound represented by formula (b-1)) 6FODA: 4,4'-diamino-2,2'-bistrifluoromethyldiphenyl ether (manufactured by ChinaTech Chemical (Tianjin) Co., Ltd.; compound represented by formula (b-2-1)) BAFL: 9,9-bis(4-aminophenyl) pyridium (manufactured by Taoka Chemical Industry Co., Ltd.; compound represented by formula (b-2-2)) HFBAPP: 2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane (manufactured by SEIKA Co., Ltd.; compound represented by formula (b-2-3)) X-22-9409: Two-terminal amine modified silicone oil "X-22-9409" (manufactured by Shin-Etsu Chemical Co., Ltd.; compound represented by formula (b-2-4)) TFMB: 2,2'-bis(trifluoromethyl)benzidine (manufactured by SEIKA Co., Ltd.; compound represented by formula (b-2-5)) 1,3-BAC: 1,3-bis(aminomethyl)cyclohexane (manufactured by Mitsubishi Gas Chemical Co., Ltd.) 4,4’-DDS: 4,4’-diaminodiphenyl sulfide (manufactured by SEIKA Co., Ltd.)

<Example 1> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 24.931g (0.100 mol) of 3, 3'-DDS, 6.373g (0.005 mol) of X-22-9409, 62.335g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Co., Ltd.), at a system internal temperature of 70°C and a nitrogen atmosphere at a speed of 200rpm Stir to obtain a solution. In this solution, 32.468g (0.105 mol) of ODPA and 15.589g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.529g was added as the third imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 162.057 g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and after cooling the internal temperature of the reaction system to 100°C, it was further stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 300°C for 30 minutes in a hot air dryer in a nitrogen environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Example 2> Into a 300mL 5-neck round-bottomed flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 23.121g (0.093 mol) of 3, 3'-DDS, 9.527g (0.007 mol) of X-22-9409, 62.182g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Co., Ltd.) at a system internal temperature of 70°C and a nitrogen environment at a speed of 200rpm Stir to obtain a solution. In this solution, 30.948g (0.100 mol) of ODPA and 15.545g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.505g was added as the third imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 162.273g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100°C, and then stirred for about 1 hour to make it Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 300°C for 30 minutes in a hot air dryer in a nitrogen environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Example 3> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 26.174g (0.105 mol) of 3, 3'-DDS, 9.155g (0.026 mol) of BAFL, 63.287g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen environment at a rotation speed of 200rpm to obtain Solution. In this solution, after adding 29.396g (0.131 mol) of HPMDA and 15.822g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) at a time, 0.663g was added as the third of imidization catalyst Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 160.859 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and the internal temperature of the reaction system was cooled to 100°C, and then stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Example 4> Into a 300mL 5-neck round-bottomed flask equipped with a stainless steel half-moon-shaped stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 24.363g (0.098mole) of 3, 3'-DDS, 12.673g (0.024 mol) of HFBAPP, 62.967g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at 200 rpm to obtain Solution. In this solution, 27.362g (0.122 mol) of HPMDA and 15.742g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.617g was added as the third imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.291 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and the internal temperature of the reaction system was cooled to 100°C, followed by stirring for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Example 5> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 26.319g (0.105 mol) of 3, 3'-DDS, 8.873g (0.026 mol) of 6FODA, 63.312g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen environment at a rotation speed of 200 rpm to obtain Solution. In this solution, after adding 29.559 g (0.132 mol) of HPMDA and 15.828 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) at one time, 0.667 g of it was added as the third of imidization catalyst Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 160.860 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and after cooling the internal temperature of the reaction system to 100°C, it was further stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Example 6> Into a 300mL 5-neck round-bottomed flask equipped with stainless steel half-moon stirring blades, nitrogen introduction tube, Dean-Stark equipped with cooling tube, thermometer, and glass end cap, put 26.505g (0.106 mol) of 3, 3'-DDS, 8.513g (0.027 mol) of TFMB, 63.345g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200rpm to obtain Solution. In this solution, after adding 29.768 g (0.133 mol) of HPMDA and 15.836 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) at a time, 0.672 g of it was added as the third of imidization catalyst Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 160.819 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100°C, and then stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Comparative example 1> Put 28.588g (0.115 mol) of 3 into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap. 3'-DDS, 62.704 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200 rpm to obtain a solution. In this solution, 35.541 g (0.115 mol) of ODPA and 15.676 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.580 g was added as the third of imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.620 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and the internal temperature of the reaction system was cooled to 100°C, followed by stirring for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

＜Comparative example 2＞ Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark with cooling tube, thermometer, and glass end cap, put 15.901g (0.064 mol) of 3, 3'-DDS, 9.156g (0.064 mol) of 1,3-BAC, 63.157g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), at a system temperature of 70°C and a nitrogen environment at a speed of 200rpm Stir to obtain a solution. In this solution, 39.536g (0.127 mol) of ODPA and 15.789g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.967g was added as the third of imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. After that, 159.801 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100°C, followed by stirring for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Comparative Example 3> Put 13.053g (0.052 mol) of 3 into a 300mL 5-neck round-bottomed flask equipped with stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with cooling tube, thermometer, and glass end cap. 3'-DDS, 18.263g (0.052 mol) of BAFL, 62.353g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200rpm to obtain Solution. In this solution, 32.455g (0.105 mol) of ODPA and 15.588g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.529g was added as the third of imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 162.059 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and after cooling the internal temperature of the reaction system to 100°C, it was further stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Comparative Example 4> Put 28.535g (0.115 mol) of 4 into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap. 4'-DDS, 62.710 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was stirred at a system internal temperature of 70°C under a nitrogen atmosphere at a rotation speed of 200 rpm to obtain a solution. In this solution, 35.600g (0.115 mol) of ODPA and 15.678g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.581g was added as the third of imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated with a heating mantle. As a result, the reaction solution became cloudy and the varnish was not obtained.

<Comparative Example 5> Put 34.192g (0.137 mol) of 3 into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap. 3'-DDS, 63.495 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200 rpm to obtain a solution. In this solution, 30.746g (0.137 mol) of HPMDA and 15.874g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.693g was added as the third of imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 160.631 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and the internal temperature of the reaction system was cooled to 100°C, and then stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Comparative Example 6> Into a 300mL 5-neck round-bottomed flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 15.819g (0.063 mol) of 3, 3'-DDS, 20.323g (0.063mole) of TFMB, 63.134g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at an internal temperature of 70°C and a nitrogen environment at a rotation speed of 200rpm to obtain Solution. In this solution, 28.427g (0.127 mol) of HPMDA and 15.784g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.641g was added as the third of imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.082 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100° C., and then stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Comparative Example 7> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 15.356g (0.062mol) of 3, 3'-DDS, 21.485g (0.062 mol) of BAFL, and 63.004g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at 200 rpm. Obtain a solution. In this solution, 27.594g (0.123 mol) of HPMDA and 15.751g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.623g was added as the third of imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. After that, 161.246g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration became 20% by mass, and the temperature in the reaction system was cooled to 100°C, and then stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 1.

<Comparative Example 8> Into a 300mL 5-neck round-bottomed flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 34.155g (0.137 mol) of 4, 4'-DDS, 63.507 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was stirred at a system internal temperature of 70°C under a nitrogen atmosphere at a rotation speed of 200 rpm to obtain a solution. In this solution, 30.795g (0.137 mol) of HPMDA and 15.877g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.695g was added as the third of imidization catalyst. Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated with a heating mantle. As a result, the reaction solution became cloudy and the varnish was not obtained.

<Example 7> Into a 300mL 5-neck round-bottomed flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, a thermometer, and a glass end cap, put 23.921g (0.096mol) of 3, 3'-DDS, 8.367g (0.024mole) of BAFL, and 62.889g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at an internal temperature of 70°C and a nitrogen environment at 200 rpm. Obtain a solution. In this solution, 13.444 g (0.060 mol) of HPMDA, 18.587 g (0.060 mol) of ODPA, and 15.722 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.606 g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.389g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100°C, and then stirred for about 1 hour to make it Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Example 8> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 22.397g (0.090 mol) of 3, 3'-DDS, 11.657g (0.022 mol) of HFBAPP, 62.620g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at 200 rpm to obtain Solution. In this solution, 12.587g (0.056 mol) of HPMDA, 17.402g (0.056 mol) of ODPA, and 15.655g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, then 0.568g was added The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.725 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and the internal temperature of the reaction system was cooled to 100°C, followed by stirring for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Example 9> Put 24.042g (0.096 mol) of 3 into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with cooling tube, thermometer, and glass end cap. 3'-DDS, 8.106g (0.024 mol) of 6FODA, 62.910g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at 200 rpm to obtain Solution. In this solution, 13.512 g (0.060 mol) of HPMDA, 18.681 g (0.060 mol) of ODPA, and 15.728 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.609 g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.362g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100°C, and then stirred for about 1 hour to make it Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Example 10> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 25.353g (0.102 mol) of 3, 3'-DDS, 8.547g (0.025 mol) of 6FODA, 63.142g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200rpm to obtain Solution. In this solution, 22.797g (0.102 mol) of HPMDA, 7.880g (0.025 mol) of ODPA, and 15.785g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.643g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.073g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and after cooling the internal temperature of the reaction system to 100°C, it was further stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Example 11> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with cooling tube, thermometer, and glass end cap, put 23.530g (0.094 mol) of 3, 3'-DDS, 12.247g (0.024 mol) of HFBAPP, 62.820g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200 rpm to obtain Solution. In this solution, 21.158 g (0.094 mol) of HPMDA, 7.313 g (0.024 mol) of ODPA, and 15.705 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.596 g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.475 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100°C, and then stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Example 12> Into a 300mL 5-neck round-bottomed flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 25.218g (0.101 mol) of 3, 3'-DDS, 8.821g (0.025 mol) of BAFL, 63.118g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200rpm to obtain Solution. In this solution, 22.676 g (0.101 mol) of HPMDA, 7.838 g (0.025 mol) of ODPA, and 15.780 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and then 0.639 g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.102g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and after cooling the internal temperature of the reaction system to 100°C, it was further stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Example 13> Into a 300mL 5-neck round-bottomed flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, a thermometer, and a glass end cap, put 23.933g (0.096mol) of 3, 3'-DDS, 12.457g (0.024mole) of HFBAPP, 62.891g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at 200 rpm to obtain Solution. In this solution, 24.211 g (0.108 mol) of HPMDA, 3.719 g (0.012 mol) of ODPA, and 15.723 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.607 g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.386 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and the internal temperature of the reaction system was cooled to 100°C, followed by stirring for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Example 14> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 25.822g (0.103 mol) of 3, 3'-DDS, 8.706g (0.026 mol) of 6FODA, 63.225g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200rpm to obtain Solution. In this solution, 26.121g (0.116 mol) of HPMDA, 4.013g (0.013 mol) of ODPA, and 15.806g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and 0.654g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 160.969 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100° C., and then stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Example 15> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 26.000g (0.104 mol) of 3, 3'-DDS, 8.351g (0.026mole) of TFMB, 63.256g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at an internal temperature of 70°C and a nitrogen environment at a rotation speed of 200rpm to obtain Solution. In this solution, 26.302g (0.117 mol) of HPMDA, 4.041g (0.013 mol) of ODPA, and 15.814g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) were added all at once, and then 0.659g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 160.930 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) was added so that the solid content concentration was 20% by mass, and after cooling the internal temperature of the reaction system to 100°C, it was further stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Comparative Example 9> Into a 300mL 5-neck round-bottomed flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 36.092g (0.103 mol) of BAFL, 63.309 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was stirred at a system internal temperature of 70°C under a nitrogen atmosphere at a rotation speed of 200 rpm to obtain a solution. In this solution, 11.598g (0.052 mol) of HPMDA, 16.035g (0.052 mol) of ODPA, and 15.577g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) were added all at once, and then 0.523g was added The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. After that, 162.113 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and the internal temperature of the reaction system was cooled to 100°C, followed by stirring for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

<Comparative Example 10> Into a 300mL 5-neck round bottom flask equipped with a stainless steel half-moon stirring blade, nitrogen introduction tube, Dean-Stark equipped with a cooling tube, thermometer, and glass end cap, put 14.109g (0.057 mol) of 3. 3'-DDS, 19.740g (0.057 mol) of BAFL, 62.651g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), stirred at a system internal temperature of 70°C and a nitrogen atmosphere at a rotation speed of 200 rpm to obtain Solution. In this solution, 12.687g (0.057 mol) of HPMDA, 17.540g (0.057 mol) of ODPA, and 15.663g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.) were added all at once, and then 0.572g was added. The triethylamine (manufactured by Kanto Chemical Co., Ltd.) as an imidization catalyst was heated by a heating mantle, and the temperature in the reaction system was raised to 190°C for about 20 minutes. The distilled components were collected, and the rotation speed was adjusted to increase the viscosity while maintaining the temperature in the reaction system at 190°C and refluxing for 5 hours. Then, 161.686 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added so that the solid content concentration was 20% by mass, and the temperature in the reaction system was cooled to 100° C., and then stirred for about 1 hour. Homogenize to obtain polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate by spin coating, and kept at 80°C for 20 minutes on a hot plate, and then heated at 260°C for 30 minutes in a hot air dryer in an air environment to make the solvent Evaporate to obtain a thin film. The results are shown in Table 2.

[Table 1]

In addition, in Comparative Examples 4 and 8, the reaction solution became cloudy during the synthesis of the polyimide resin, and the varnish could not be obtained. Therefore, the physical properties of the film could not be measured. In addition, when the film of Comparative Example 5 was immersed in a mixed acid in the acid resistance test, the YI and b* after the immersion could not be measured due to significant deterioration. Therefore, ΔYI and Δb* of Comparative Example 5 could not be obtained.

[Table 2]

As shown in Table 1, the polyimide films of Examples 1 to 6 used HPMDA or ODPA as the tetracarboxylic acid component, and used 3,3'-DDS and specific second diamines (6FODA, BAFL, HFBAPP, X-22-9409, or TFMB) are prepared as diamine components. As a result, it is excellent in colorless transparency, optical isotropy, and chemical resistance (solvent resistance, acid resistance, and alkali resistance). On the other hand, in Comparative Examples 1 to 4, although ODPA was used as the tetracarboxylic acid component, the diamine component was not a constitution of the present invention. The polyimide film of Comparative Example 1 prepared using only 3,3'-DDS as the diamine component has poor colorless transparency and optical isotropy. The polyimide film of Comparative Example 2 prepared by using 3,3'-DDS and a specific diamine (1,3-BAC) other than the second diamine as the diamine component has poor solvent resistance. Although it is made by using 3,3'-DDS and a specific second diamine (BAFL) as the diamine components, the ratio of 3,3'-DDS is less than 70 mol% of the polymer of Comparative Example 3 The imide film has poor colorless transparency (total light transmittance), optical isotropy and poor acid resistance. In Comparative Example 4 using 4,4'-DDS as the diamine component, the reaction solution became cloudy during the synthesis of the polyimide resin, and the varnish could not be obtained. In Comparative Examples 5 to 8, although HPMDA was used as the tetracarboxylic acid component, the diamine component was not a constitution of the present invention. The polyimide film of Comparative Example 5 prepared using only 3,3'-DDS as the diamine component had poor acid resistance. Although it is made by using 3,3'-DDS and a specific second diamine (TFMB) as the diamine components, the ratio of 3,3'-DDS is less than 70 mol% in Comparative Example 6 The imide film has poor solvent resistance. Although it is made by using 3,3'-DDS and a specific second diamine (BAFL) as diamine components, the ratio of 3,3'-DDS is less than 70 mol% in Comparative Example 7 The imide film has poor acid resistance. In Comparative Example 8 using 4,4'-DDS as the diamine component, the reaction solution became cloudy during the synthesis of the polyimide resin, and the varnish could not be obtained.

Also, as shown in Table 2, the polyimide films of Examples 7 to 15 prepared by using HPMDA and ODPA as the tetracarboxylic acid components have colorless transparency, optical isotropy, and chemical resistance (solvent resistance). Performance, acid resistance and alkali resistance) are also excellent. On the other hand, in Comparative Examples 9 and 10, although HPMDA and ODPA were used as the tetracarboxylic acid component, the diamine component was not a constitution of the present invention. The polyimide film of Comparative Example 9 prepared using only BAFL as the diamine component had poor acid resistance. Although it is made by using 3,3'-DDS and a specific second diamine (BAFL) as diamine components, the ratio of 3,3'-DDS is less than 70 mol% in Comparative Example 10 The imide film has poor optical isotropy and acid resistance.

Claims (10)

A polyimide resin having a structural unit A derived from tetracarboxylic dianhydride and a structural unit B derived from a diamine; the structural unit A contains the structural unit (A-1), and the structural unit (A-1) is selected from The group consisting of the structural unit (A-1-1) of the compound represented by the following formula (a-1-1) and the structural unit (A-1-2) from the compound represented by the following formula (a-1-2) At least one of them; The structural unit B contains the structural unit (B-1) derived from the compound represented by the following formula (b-1) and the structural unit (B-2), and the structural unit (B-2) is selected from The structural unit (B-2-1) of the compound represented by the following formula (b-2-1), the structural unit (B-2-2) from the compound represented by the following formula (b-2-2), and the structural unit (B-2-2) from the compound represented by the following formula (b-2-1) The structural unit (B-2-3) of the compound represented by (b-2-3), the structural unit (B-2-4) derived from the compound represented by the following formula (b-2-4), and the structural unit (B-2-4) derived from the compound represented by the following formula ( b-2-5) at least one of the group consisting of the constituent unit (B-2-5) of the compound represented; the ratio of the constituent unit (B-1) in the constituent unit B is 70 mol% or more;

In formula (b-2-2), R is each independently a hydrogen atom, a fluorine atom or a methyl group, and in formula (b-2-4), R ¹ to R ⁴ are each independently a monovalent aliphatic group or a monovalent aliphatic group For the aromatic group, Z ¹ and Z ² are each independently a divalent aliphatic group or a divalent aromatic group, and r is a positive integer. Such as the polyimide resin of claim 1, wherein the ratio of the structural unit (B-1) in the structural unit B is 70-97 mol%, and the ratio of the structural unit (B-2) in the structural unit B is 3～30mol%. The polyimide resin of claim 1 or 2, wherein the ratio of the constituent unit (A-1) in the constituent unit A is 50 mol% or more. The polyimide resin according to any one of claims 1 to 3, wherein the structural unit (B-2) is the structural unit (B-2-1). The polyimide resin according to any one of claims 1 to 3, wherein the structural unit (B-2) is the structural unit (B-2-2). The polyimide resin according to any one of claims 1 to 3, wherein the structural unit (B-2) is the structural unit (B-2-3). The polyimide resin according to any one of claims 1 to 3, wherein the structural unit (B-2) is the structural unit (B-2-4). The polyimide resin according to any one of claims 1 to 3, wherein the structural unit (B-2) is the structural unit (B-2-5). A polyimide varnish made by dissolving the polyimide resin of any one of claims 1 to 8 in an organic solvent. A polyimide film containing the polyimide resin according to any one of claims 1 to 8.