TWI636077B - Polyimine film and method of producing the same - Google Patents

Abstract

An object of the present invention is to provide a polyimide film which can be thermally corrected for planar deterioration when a polyimide film is wound into a roll. A method of producing the polyimide film is also provided.

The polyimine film of the present invention is characterized in that the total light transmittance is 80% or more, and the yellow index value (YI value) is 4.0 or less, and 1 g or more is dissolved in 100 g of dichloromethane at 25 ° C. The heat shrinkage rate defined by the above formula is in the range of 0.5 to 20.0%, and the heat shrinkage rate (%) = {(Lo-L) / Lo} × 100

(However, Lo represents the length of the sample before the test at 25 ° C, and L represents the length of the sample when the sample is stored at 230 ° C for 10 minutes and then cooled to 25 ° C.).

Description

Polyimine film and method of producing the same

The present invention relates to a polyimide film and a method for producing the same, and more particularly to a polyimide film which can be improved in planarity when a film is wound into a roll by heat correction.

Polyimine has excellent flexural resistance or high modulus of elasticity, and is therefore considered to be used as a flexible printed circuit (FPC) or an organic electroluminescent device (also referred to as an "organic EL device"). The use of the components. However, it is colored yellowish brown due to the formation of intramolecular conjugates or charge transfer complexes, and it is difficult to use in fields requiring transparency.

Regarding the countermeasures, there has been proposed a method of introducing a fluorine group into a polyimine, or imparting flexibility to a main chain, or introducing a fluffy side chain or the like to inhibit formation of a charge transport complex. Further, there has been proposed a method of exhibiting transparency by using a semi-alicyclic or full-alicyclic polyimine which does not theoretically form a charge-transfer complex (refer to, for example, Patent Document 1).

Further, there has been proposed a polyimide film having improved transparency without coloring (refer to Patent Document 2).

A polyimide film having improved transparency without coloring is excellent in optical characteristics, and thus can be expected to be used for display applications.

However, the colorless and transparent polyimide film has a problem that the films are easily attached to each other when the film is wound into a roll. In addition, there is also a problem that the planarity is easily deteriorated by the curl deformation of the roller.

In order to improve the planarity deterioration caused by the above-described curling deformation, it is considered to improve the slip property by mixing an inorganic filler on a polyimide film to prevent the adhesion of the polyimide films to each other, and to reduce the planarity deterioration caused by the curl deformation. method. However, the polyimide film has a problem that only a small amount of inorganic filler can be added, and it cannot be sufficiently improved by adding an inorganic filler.

Then, the present inventors reviewed a method of improving the planarity by thermally correcting a colorless and transparent polyimide film which is deteriorated in planarity due to the above-described curl deformation by heat shrinkage.

However, it is known that a polyimide film has higher strength and heat resistance than a general polymer film. Since it has the advantage of small shape change due to heat, it has also been reviewed for use in circuit boards of electronic materials. Therefore, the heat shrinkage rate is not boldly increased and used.

In fact, after review by the present inventors, even if the film formed by forming the polyimide film is heat-treated again, the heat shrinkage rate is small.

Therefore, there is a problem that it is difficult to correct the planar heat by heat shrinkage.

[Previous Technical Literature] [Patent Document]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2000-53767

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2010-100674

The present invention has been made in view of the above problems and circumstances, and an object of the present invention is to provide a polyimide film which can improve planarity deterioration when a film is wound into a roll shape by thermal correction. A method of producing the polyimide film is also provided.

In order to solve the above problems associated with the present invention, it has been found that the heat shrinkage rate of the polyimide film is in the range of 0.5 to 20.0% in the course of reviewing the cause of the above problem. The present invention has been completed by correcting the planarity deterioration heat when the amine film is wound into a roll.

That is, the subject to which the present invention relates can be solved by the following means.

A polyimine film which is a polyimine film containing polyimine as a main component, characterized in that a total light transmittance is 80% or more and a yellow index value (YI value) is 4.0 or less. And dissolved at 1 g or more with respect to 100 g of dichloromethane at 25 ° C, and the heat shrinkage rate defined by the following formula is in the range of 0.5 to 20.0%, and the heat shrinkage ratio (%) = {(Lo-L) / Lo }×100

(However, Lo represents the length of the sample before the test at 25 ° C, and L represents the length of the sample when the sample is stored at 230 ° C for 10 minutes and then cooled to 25 ° C.).

2. The polyimide film according to item 1, wherein the inorganic filler is contained in the range of 0.01 to 2.0% by mass.

3. The polyimine film according to item 1 or 2, which comprises a fluorinated polyimine as the aforementioned polyimine.

A method for producing a polyimine film, which is a method for producing a polyimide film of a polyimide film according to any one of items 1 to 3, characterized in that the polyimine The polyimine contained in the film uses 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl as the diamine, and 2,2-bis(3,4-dicarboxyl) is used. Poly-proline or polyimine synthesized by polymerization of phenyl) hexafluoropropane dianhydride or biphenyl tetracarboxylic dianhydride as acid dianhydride, using the above-mentioned synthetic polyaminic acid or polyimine A polyimide film is produced.

A method for producing a polyimide film, which is a method for producing a polyimide film of a polyimide film according to any one of items 1 to 3, which comprises: a polyamine The acid or polyimine is dissolved in a solvent having a boiling point of 40 to 80 ° C to prepare a coating preparation step of the coating; the coating material is cast on the support to form a casting step of the casting film; and the solvent is evaporated from the casting film. a solvent evaporation step; a stripping step of peeling the cast film for evaporating the solvent from the support; drying the peeled cast film at 10 to 200 ° C to obtain a film drying step; and extending the dried film to extend step .

According to the above-described means of the present invention, it is possible to provide a polyimide film which can be improved in planarity when the film is wound into a roll by heat correction. A method of producing the polyimide film can also be provided.

The expression mechanism or mechanism of action of the effects of the present invention is still unclear, but it is presumed as follows.

In the conventional polyimide film, a polyimide film having a rigid molecular structure is produced by a high temperature program of 300 ° C or higher in a film forming process. Therefore, a polyimide film having high heat resistance can be obtained, but conversely, even if heating is performed again, the heat shrinkage rate is small. Therefore, it is not possible to improve the planarity deterioration when wound into a roll shape by thermal correction.

The present inventors have found that a polyimide film can be obtained by adjusting and combining various conditions of drying temperature, type of solvent, elongation rate, and residual solvent ratio during stretching in the production process of the polyimide film. The heat shrinkage rate is in the range of 0.5 to 20.0%, whereby the planarity deterioration can be improved.

The reason why the heat shrinkage rate of the polyimide film can be increased is presumably because the polyimine does not become excessively rigid due to various conditions of the manufacturing process (drying at a low temperature, etc.), and it is possible to The arrangement of the soft polymer chains which are reheated and contracted.

In addition, the polyimine film associated with the present invention is a colorless, transparent polyimide film. The colorless and transparent standard preferably has a total light transmittance of 80% or more and a yellow index value (YI value) of 4.0 or less. The polyimide film has a total light transmittance of 80% or more and a yellow index value (YI value) of 4.0. The polyimine film is introduced into a fluffy side chain or the like in order to be transparent or colorless, thereby hindering the formation of a charge transfer complex which causes coloration, and thus the molecular chain is softer than usual polyimine. In addition, the gap between the molecular chains tends to increase. Therefore, it is also presumed that when stress is applied during film formation of the polyimide film, the polymer chain which is forcibly aligned is heat-treated again, and the polymer chain is easily thermally contracted.

In addition, it is presumed that the polyimine film of 1 g or more is dissolved in 100 g of methylene chloride at 25 ° C, and the solubility thereof is high. Therefore, it is easy to carry out solution casting, and it is easy to adjust the manufacturing conditions of the manufacturing process. The polymer chain is in a state of being easily heat-shrinked.

As described above, in the production process of the polyimide film, by adjusting and combining various conditions, the heat shrinkage ratio of the polyimide film is first achieved in the range of 0.5 to 20.0%.

By setting the heat shrinkage rate during reheating to a range of 0.5 to 20.0%, the polyimide film which is deteriorated in planarity due to curl deformation can be stretched by reheating, so that planar heat can be corrected.

The polyimine film of the present invention is a colorless, transparent, and highly soluble polyimide film having a high solubility in methylene chloride.

That is, the polyimine film of the present invention is a polyimide film containing polyimine as a main component, and has a total light transmittance of 80% or more and a yellow index value (YI value) of 4.0. Hereinafter, 1 g or more is dissolved with respect to 100 g of dichloromethane at 25 ° C, and the heat is defined by the following formula The shrinkage rate is in the range of 0.5~20.0%, and the heat shrinkage rate (%)={(Lo-L)/Lo}×100

(However, Lo represents the length of the sample before the test at 25 ° C, and L represents the length of the sample when the sample is stored at 230 ° C for 10 minutes and then cooled to 25 ° C.).

This feature is a technical feature common to the invention associated with each request item.

In the embodiment of the present invention, the polyimine film preferably contains an inorganic filler in a range of 0.01 to 2.0% by mass from the viewpoint of exhibiting the effects of the present invention. In the present invention, even when the amount of the inorganic filler added is less than 2.0% by mass, the effects of the present invention can be obtained, and therefore the haze can be lowered.

Further, from the viewpoint of the effect of improving the transparency of the polyimide film and the effect of improving the planarity by heat correction, the polyimine is preferably a fluorinated polyimide. Further, the content of fluorine is in the range of 1 to 40% by mass of the polyimide film, and the effect of the present invention is large, which is preferable.

From the viewpoint of obtaining a polyimide film having a large effect of planarity heat correction, the method for producing the polyimide film of the present invention preferably uses 2,2'-bis(trifluoromethyl)- 4,4'-diaminobiphenyl as a diamine, using 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride or biphenyltetracarboxylic dianhydride as acid dianhydride Polyimine, using the previously synthesized polyimine to produce a polyimide film.

From the viewpoint of having an effect of improving planarity by heat correction, a film for producing a film of the polyimide film of the present invention is produced. The method preferably comprises: dissolving poly-proline or polyimine in a solvent having a boiling point of 40 to 80 ° C to prepare a coating adjustment step of the coating; casting the coating onto the support to form a cast film a casting step; a solvent evaporation step of evaporating the solvent from the casting film; a peeling step of peeling the cast film for evaporating the solvent from the support; and drying the peeled cast film at 10 to 200 ° C to obtain a film drying step And a manufacturing method of the aspect of extending the step of extending the dried film.

Hereinafter, the present invention and its constituent elements, and the present embodiment and aspects will be described in detail. In addition, the "~" used in the present invention means that the numerical values described before and after are referred to as the lower limit and the upper limit.

<Summary of Polyimine Film of the Present Invention>

The polyimine film of the present invention is a colorless, transparent polyimide film containing polyimine as a main component.

That is, the polyimine film of the present invention is a polyimide film containing polyimine as a main component, and has a total light transmittance of 80% or more and a yellow index value (YI value) of 4.0. Hereinafter, 1 g or more is dissolved in 100 g of dichloromethane at 25 ° C, and the heat shrinkage ratio defined by the following formula is in the range of 0.5 to 20.0%, and the heat shrinkage ratio (%) = {(Lo-L) / Lo}×100

(However, Lo represents the length of the sample before the test at 25 ° C, and L represents the length of the sample when the sample is stored at 230 ° C for 10 minutes and then cooled to 25 ° C.).

In the present invention, the polyimine is contained as a main component, which means that it is in the film. The total amount of the polyimine and the polyamic acid is 50% by mass or more. It is preferably 80% by mass or more.

<polyimine]

The polyimine which is related to the present invention is a transparent heat-resistant resin having a quinone imine structure (hereinafter also referred to as polyimine), and is a transparent heat-resistant resin containing a quinone bond in a repeating unit. The polyimine film of the present invention contains polyamic acid or polyimine. Polylysine or polyimine is preferably formed from a diamine or a derivative thereof and an acid anhydride or a derivative thereof.

The polyimine which is suitable for the present invention is a polyimine having a structure represented by the following formula (1.1), and examples thereof include polyamidoximine, polyetherimine, and polyesterimide.

(1.1) Polyimine having a structure represented by formula (1.1) or formula (1.2) (1.1.1) Structure of the anhydride side

The polyimine or polylysine which can be used in the present invention is particularly preferably a polyimine (hereinafter referred to as polyimine (A)) having a repeating unit represented by the following formula (1.1) or having A poly-proline (hereinafter referred to as polyamine acid (A')) of a repeating unit represented by the following formula (1.2).

The polyaminic acid (A'), as described above, corresponds to a structure in which a part of the quinone imine bond of the polyimine (A) is dissociated, and a detailed description of the poly-proline (A'), which corresponds to poly The imine (A) is considered, so the following is a detailed description of the representative polyimine (A).

In the formulae (1.1) and (1.2), R is an aromatic hydrocarbon ring or an aromatic hetero ring, or a tetravalent aliphatic hydrocarbon group or an alicyclic hydrocarbon group having 4 to 39 carbon atoms. Φ is a divalent aliphatic hydrocarbon group having 2 to 39 carbon atoms, an alicyclic hydrocarbon group, an aromatic hydrocarbon group, or a group composed of the combinations, and may contain a group selected from -O-, -SO ₂ -, -CO At least one group of -, -CH ₂ -, -C(CH ₃ ) ₂ -, -OSi(CH ₃ ) ₂ -, -C ₂ H ₄ O-, and -S- is used as a bonding group .

Examples of the aromatic hydrocarbon ring represented by R include an anthracene ring, a benzene ring, a biphenyl ring, a naphthalene ring, an anthracene ring, an anthracene ring, a phenanthrene ring, an anthracene ring, and Ring, fused tetraphenyl ring, extended triphenyl ring, ortho-triphenyl ring, m-terphenyl ring, p-terphenyl ring, anthracene ring, anthracene ring, fluoranthene ring, thick tetraphenyl ring, thick pentacene ring, anthracene ring, Penfen ring, anthracycline ring, anthracycline ring, pyridinium ring, indole ring and the like.

In the same manner, the aromatic heterocyclic ring represented by R may, for example, be a thioring ring, a furan ring, a thiophene ring, an oxazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring or a triazine. Ring, oxadiazole ring, triazole ring, imidazole ring, pyrazole ring, thiazole ring, anthracene ring, benzimidazole ring, benzene And a thiazole ring, a benzoxazole ring, a quinoxaline ring, a quinazoline ring, a pyridazine ring, a thienothiophene ring, an indazole ring, an azaindazole ring (indicating any one of the carbon atoms constituting the indazole ring) The above substituted by a nitrogen atom), a dibenzothiarrole ring, a dibenzofuran ring, a dibenzothiophene ring, a ring in which any one or more carbon atoms constituting the benzothiophene ring or the dibenzofuran ring are substituted by a nitrogen atom , benzodifuran ring, benzodithiophene ring, acridine ring, benzoquinoline ring, phenazine ring, phenanthrene parallel toluidine ring, phenanthroline ring, cyclopyridazine ring, quinoxaline ring, tepenizine ring , quinoxaline ring, triphenyl dithiazine ring, triphenyl dioxazine ring, phenazine ring, pyridazine ring, acridine ring, naphthopyrene ring, naphthothiophene ring, naphtho-difuran ring, Naphtho-dithiophene ring, furfuran ring, fluorene furan ring, thiophene ring, quinone dithiophene ring, thioxan ring, thiophene ring, dibenzoxazole ring, indolocarbazole ring, dithiophene Benzene ring and the like.

The tetravalent aliphatic hydrocarbon group having 4 to 39 carbon atoms represented by R may, for example, be butane-1,1,4,4-tetrayl, octane-1,1,8,8-tetrayl, decane- A group such as 1,1,10,10-tetrayl or the like.

Further, the tetravalent alicyclic hydrocarbon group having 4 to 39 carbon atoms represented by R may, for example, be cyclobutane-1,2,3,4-tetrayl or cyclopentane-1,2,4,5-tetra. Base, cyclohexane-1,2,4,5-tetrayl, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetrayl,bicyclo[2.2,2]octane-2 , 3,5,6-tetrayl, 3,3',4,4'-dicyclohexyltetrayl, 3,6-dimethylcyclohexane-1,2,4,5-tetrayl, 3, a group of 6-diphenylcyclohexane-1,2,4,5-tetrayl or the like.

The divalent aliphatic hydrocarbon group having 2 to 39 carbon atoms with or without the above-mentioned bonding group represented by Φ may, for example, be a group represented by the following structural formula.

In the above structural formula, n represents the number of repeating units, preferably 1 to 5, and preferably 1 to 3. Further, X is an alkanediyl group having 1 to 3 carbon atoms, that is, a methylene group, an ethylidene group, a trimethylene group, and a propane-1,2-diyl group, preferably a methylene group.

The divalent alicyclic hydrocarbon group having 2 to 39 carbon atoms which may or may not have the above-mentioned bond group represented by Φ may, for example, be a group represented by the following structural formula.

The divalent aromatic hydrocarbon group having 2 to 39 carbon atoms with or without the above-mentioned bonding group, which is represented by Φ, may, for example, be a group represented by the following structural formula.

The group consisting of a combination of an aliphatic hydrocarbon group, an alicyclic hydrocarbon group and an aromatic hydrocarbon group represented by Φ is, for example, a group represented by the following structural formula.

The group represented by Φ is preferably a divalent aromatic hydrocarbon group having 2 to 39 carbon atoms having a bonding group, or a combination of the aromatic hydrocarbon group and an aliphatic hydrocarbon group, and particularly preferably a group represented by the following structural formula. .

The acid anhydride used in the present invention is a carboxylic acid anhydride, preferably a derivative of an aliphatic or alicyclic tetracarboxylic acid, and examples thereof include an aliphatic or alicyclic tetracarboxylic acid ester, an aliphatic or alicyclic tetracarboxylic acid Anhydride, etc. Further, among the aliphatic or alicyclic tetracarboxylic acids or derivatives thereof, an alicyclic tetracarboxylic dianhydride is preferred.

Here, the derivative means a compound which can be changed to an aliphatic or alicyclic tetracarboxylic acid, for example, in the case of an aliphatic tetracarboxylic dianhydride, a compound having two carboxyl groups instead of the anhydride, and the two are suitably used. A compound of an esterified product obtained by esterifying one or both of the carboxyl groups, or a ruthenium chloride obtained by chlorinating one or both of the two carboxyl groups.

By using such a mercapto compound, a polyimide film having high heat resistance, excellent optical characteristics, and little coloration (yellowing) can be obtained.

Examples of the aliphatic tetracarboxylic acid include 1,2,3,4-butanetetracarboxylic acid and the like. Examples of the alicyclic tetracarboxylic acid include 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,4,5-cyclopentanetetracarboxylic acid, 1,2,4,5-cyclohexane. Alkanetetracarboxylic acid, double ring [2.2.2] Oct-7-ene-2,3,5,6-tetracarboxylic acid, bicyclo[2.2.2]octane-2,3,5,6-tetracarboxylic acid and the like.

The aliphatic tetracarboxylic acid ester may, for example, be a monoalkyl ester, a dialkyl ester, a trialkyl ester or a tetraalkyl ester of the above aliphatic tetracarboxylic acid. Examples of the alicyclic tetracarboxylic acid esters include monoalkyl esters, dialkyl esters, trialkyl esters, and tetraalkyl esters of the above alicyclic tetracarboxylic acid. Further, the alkyl moiety is preferably an alkyl group having 1 to 5 carbon atoms, and an alkyl group having 1 to 3 carbon atoms is preferred.

Examples of the aliphatic tetracarboxylic dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride and the like. Examples of the alicyclic tetracarboxylic dianhydride include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclopentanetetracarboxylic dianhydride, 1,2, 4,5-cyclohexanetetracarboxylic dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, bicyclo[2.2.2]octane-2, 3,5,6-tetracarboxylic dianhydride and the like. Particularly preferred is 1,2,4,5-cyclohexanetetracarboxylic dianhydride. In general, a polydiimine having an aliphatic diamine as a constituent component, a polyamine and a diamine of a middle product thereof form a strong salt, and therefore, in order to achieve high molecular weight, it is preferred to use a salt having a high solubility. Solvent (for example, cresol, N,N-dimethylacetamide, γ-butyrolactone, N-methyl-2-pyrrolidone, etc.). However, when the polydiimine having a fatty diamine as a constituent component is composed of 1,2,4,5-cyclohexanetetracarboxylic dianhydride as a constituent component, the salt of polyglycine and diamine is Since it is bonded by a weak bond, it is easy to be highly polymerized, and a flexible film is easily obtained.

Others such as 4,4'-biphenyltetracarboxylic anhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 2,3,3',4'-biphenyltetracarboxylic dianhydride may also be used. 4,4'-oxydiphthalic anhydride, 3,3',4,4'-benzophenonetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 4-( 2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetra Hydronaphthalene-1,2-dicarboxylic anhydride, 5-[2,5-dioxotetrahydrofuranyl-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 3,3',4 , 4'-diphenylfluorene tetracarboxylic dianhydride, 3,4'-oxydiphthalic anhydride, 3,4,9,10-decanetetracarboxylic dianhydride (Pigment Red 224) 1,2,3,4- Tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride tricyclo[6.4.0.02,7]dodecane-1,8:2,7-tetracarboxylic dianhydride, and the like.

Further, an acid anhydride having an anthracene skeleton or a derivative thereof can also be used. It has the effect of improving the unique coloration of polyimine. As the acid anhydride having an anthracene skeleton, for example, 9,9-bis(3,4-dicarboxyphenyl)decanoic acid dianhydride, 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl group can be used. ] phthalic acid dianhydride, 9,9-bis[4-(3,4-dicarboxyphenoxy)-3-phenylphenyl]decanoic acid dianhydride, and the like.

The aromatic, aliphatic or alicyclic tetracarboxylic acid or a derivative thereof may be used alone or in combination of two or more. Further, other tetracarboxylic acids or derivatives thereof (especially dianhydrides) may be used in combination without impairing the solvent solubility of the polyimide, the flexibility of the polyimide film, the hot pressability, and the transparency. ).

Examples of the other tetracarboxylic acid or a derivative thereof include pyromellitic acid, 3,3', 4,4'-biphenyltetracarboxylic acid, and 2,3,3',4'-biphenyltetracarboxylic acid. 2,2-bis(3,4-dicarboxyphenyl)propane, 2,2-bis(2,3-dicarboxyphenyl)propane, 2,2-bis(3,4-dicarboxyphenyl)- 1,1,1,3,3,3-hexafluoropropane, 2,2-bis(2,3-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane, double ( 3,4-Dicarboxyphenyl)indole, bis(3,4-dicarboxyphenyl)ether, bis(2,3-dicarboxyphenyl)ether, 3,3',4,4'-benzophenone Tetracarboxylic acid, 2,2',3,3'-benzophenonetetracarboxylic acid, 4,4-(p-phenylenedioxy)diphthalic acid, 4,4-(m-phenylenedioxy)didecanoic acid An aromatic system such as 1,1-bis(2,3-dicarboxyphenyl)ethane, bis(2,3-dicarboxyphenyl)methane or bis(3,4-dicarboxyphenyl)methane Tetracarboxylic acid and such derivatives (especially dianhydride); aliphatic tetracarboxylic acids having 1 to 3 carbon atoms such as ethylene tetracarboxylic acid; and such derivatives (especially dianhydride).

The acid dianhydride is preferably 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride or biphenyltetracarboxylic acid from the viewpoint of excellent transparency and heat correction by heat shrinkage. Diacid anhydride.

The repeating unit represented by the above formula (1.1) is preferably 10 to 100 mol%, preferably 50 to 100 mol%, more preferably 80 to 100 mol%, more preferably all of the repeating units. 90~100% by mole. Further, in the molecule of the polyimine (A), the number of repeating units of the formula (1.1) is from 10 to 2,000, preferably from 20 to 200, and in this range, the glass transition temperature is further from 230 to 350 ° C. Good, 250~330 °C is better.

(1.1.2) Structure of the diamine side

The diamine or a derivative thereof is preferably, for example, an aromatic diamine or an isocyanate, and an aromatic diamine is preferred.

The diamine or a derivative thereof used in the present invention may be any of an aromatic diamine, an aliphatic diamine or a mixture thereof, and it is preferably from the viewpoint of suppressing whitening of the polyimide film. Aromatic diamine.

Further, in the present invention, the "aromatic diamine" means a diamine in which an amine group is directly bonded to an aromatic ring, and a part of the structure may further contain an aliphatic hydrocarbon group, an alicyclic hydrocarbon group, and other substituents (for example, a halogen atom). , sulfonyl, carbonyl, oxygen, etc.). The "aliphatic diamine" means a diamine in which an amine group is directly bonded to an aliphatic hydrocarbon group or an alicyclic hydrocarbon group, and a part of the structure may contain an aromatic hydrocarbon group or another substituent (for example, a halogen atom, Sulfonyl, carbonyl, oxygen atom, etc.).

Examples of the aromatic diamine include p-phenylenediamine, m-phenylenediamine, 2,4-diaminotoluene, 2,6-diaminotoluene, benzidine, o-toluidine, and m-toluidine. , bis(trifluoromethyl)benzidine, octafluorobenzidine, 3,3'-dihydroxy-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'- Diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,6-diamine Naphthyl, 1,5-diaminonaphthalene, 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4 , 4'-diaminodiphenyl hydrazine, 3,4'-diaminodiphenyl hydrazine, 4,4'-diaminobenzophenone, 2,2-bis(4-(4-aminophenoxy) Phenyl)propane, 2,2-bis(4-(2-methyl-4-aminophenoxy)phenyl)propane, 2,2-bis(4-(2,6-dimethyl) 4-aminophenoxy)phenyl)propane, 2,2-bis(4-(4-aminophenoxy)phenyl)hexafluoropropane, 2,2-bis(4-(2-A) 4-aminophenoxy)phenyl)hexafluoropropane, 2,2-bis(4-(2,6-dimethyl-4-aminophenoxy)phenyl)hexafluoropropane, 4 , 4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(2-methyl-4-aminophenoxy)biphenyl, 4,4'-bis (2,6 -dimethyl-4- Aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, bis(4-(4-aminophenoxy)phenyl)anthracene, bis(4-( 2-methyl-4-aminophenoxy)phenyl)indole, bis(4-(2,6-dimethyl-4-aminophenoxy)phenyl)indole, bis(4-(4) -aminophenoxy)phenyl)ether, bis(4-(2-methyl-4-aminophenoxy)phenyl)ether, bis(4-(2,6-dimethyl-4-) Aminophenoxy)phenyl)ether, 1,4-bis(4-aminophenoxy)benzene, 1,4-bis(2-methyl-4-aminophenoxy)benzene, 1, 4-bis(2,6-dimethyl-4-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,3-bis(2-methyl-4) -aminophenoxy)benzene, 1,3-bis(2,6-dimethyl-4-aminophenoxy)benzene, 2,2-bis(4-aminophenyl)propane Alkane, 2,2-bis(2-methyl-4-aminophenyl)propane, 2,2-bis(3-methyl-4-aminophenyl)propane, 2,2-bis(3- Ethyl-4-aminophenyl)propane, 2,2-bis(3,5-dimethyl-4-aminophenyl)propane, 2,2-bis(2,6-dimethyl-4) -aminophenyl)propane, 2,2-bis(4-aminophenyl)hexafluoropropane, 2,2-bis(2-methyl-4-aminophenyl)hexafluoropropane, 2,2 - bis(2,6-dimethyl-4-aminophenyl)hexafluoropropane, α,α'-bis(4-aminophenyl)-1,4-diisopropylbenzene, α,α '-Bis(2-methyl-4-aminophenyl)-1,4-diisopropylbenzene, α,α'-bis(2,6-dimethyl-4-aminophenyl)- 1,4-diisopropylbenzene, α,α'-bis(3-aminophenyl)-1,4-diisopropylbenzene, α,α'-bis(4-aminophenyl)- 1,3-diisopropylbenzene, α,α'-bis(2-methyl-4-aminophenyl)-1,3-diisopropylbenzene, α,α'-bis (2,6 -Dimethyl-4-aminophenyl)-1,3-diisopropylbenzene, α,α'-bis(3-aminophenyl)-1,3-diisopropylbenzene, 1, 1-bis(4-aminophenyl)cyclopentane, 1,1-bis(2-methyl-4-aminophenyl)cyclopentane, 1,1-bis(2,6-dimethyl 4-aminophenyl)cyclopentane, 1,1-bis(4-aminophenyl)cyclohexane, 1,1-bis(2-methyl-4-aminophenyl)cyclohexane 1,1-bis(2,6-dimethyl-4-aminophenyl)cyclohexane, 1,1-bis(4-aminophenyl)4-methyl-cyclohexane, 1, 1-bis(4-aminophenyl)norbornane, 1,1-bis(2-methyl-4-aminophenyl)norbornane, 1,1-bis(2,6-dimethyl 4-aminophenyl)norbornane, 1,1-bis(4-aminophenyl)adamantane, 1,1-bis(2-methyl-4-aminophenyl)adamantane, 1 , 1-bis(2,6-dimethyl-4-aminophenyl)adamantane, 1,4-phenylenediamine, 3,3'-diaminobenzophenone, 2,2-bis (3 -aminophenyl)hexafluoropropane, 3-aminobenzylamine, 2,2-bis(3-amino-4-methylphenyl)hexafluoropropane, 1,3-bis(3-amino group Phenoxy)benzene, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, bis[4-(3-aminophenoxy)phenyl]anthracene, 1,3- Bis[2-(4-aminophenyl)-2-propyl]benzene, bis(2-aminophenyl) sulfide, Bis(4-aminophenyl) sulfide, 1,3-bis(3-aminopropyl)tetramethyldioxane, 4,4'-diamino-3,3'-dimethyldi Phenylmethane, 3,3'-diaminodiphenylmethane, 4,4'-ethylenediphenylamine, 4,4'-methylenebis(cyclohexylamine), 4,4'-methylene double (2,6-diethylaniline), 4,4'-methylenebis(2-methylcyclohexylamine), and the like.

The aliphatic diamine may, for example, be ethylenediamine, hexamethylenediamine, polyethylene glycol bis(3-aminopropyl)ether, polypropylene glycol bis(3-aminopropyl)ether, 1,3-double (aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, m-diamine, p-nonanediamine, 1,4-bis(2-amino-isopropyl)benzene, 1,3-bis(2-amino-isopropyl)benzene, isophoronediamine, norbornanediamine, decanediamine, 4,4'-diaminodicyclohexylmethane, 3 , 3'-dimethyl-4,4'-diaminodicyclohexylmethane, 3,3'-diethyl-4,4'-diaminodicyclohexylmethane, 3,3',5, 5'-Tetramethyl-4,4'-diaminodicyclohexylmethane, 2,3-bis(aminomethyl)-bicyclo[2.2.1]heptane, 2,5-bis(aminomethyl) -bicyclo[2.2.1]heptane, 2,6-bis(aminomethyl)-bicyclo[2.2.1]heptane, 2,2-bis(4,4'-diaminocyclohexyl)propane, 2 , 2-bis(4,4'-diaminemethylcyclohexyl)propane, and the like.

Further, in order to improve the coloring characteristic of polyimine, a diamine having an anthracene skeleton or a derivative thereof may also be used. For example, 9,9-bis[4-(4-aminophenoxy)phenyl]anthracene, 9,9-bis[4-(4-aminophenoxy)-3-phenylphenyl] can be used. Ruthenium, 9,9-bis[4-(3-aminophenoxy)-3-phenylphenyl]anthracene, 9,9-bis[4-(2-aminophenoxy)-3-benzene Phenyl]fluorene, 9,9-bis[4-(4-amino-3-methylphenoxy)-3-phenylphenyl]indole, 9,9-bis[4-(4-amine 2-methylphenoxy)-3-phenylphenyl]indole, 9,9-bis[4-(4-amino-3-ethylphenoxy)-3-phenylphenyl]indole Wait.

Further, a diamine compound having a triazine mother nucleus represented by the following formula is suitably used.

In the diamine compound of the above formula having a triazine nucleus, R ¹ represents a hydrogen atom or an alkyl group or an aromatic group having a carbon number of 1 to 12 (preferably a carbon number of 1 to 10, more preferably a carbon number of 1 to 6). R ² represents an alkyl group or an aromatic group having 1 to 12 carbon atoms (preferably having a carbon number of 1 to 10, more preferably 1 to 6 carbon atoms), and R ¹ and R ² may be different or the same.

The alkyl group or the aryl group having 1 to 12 carbon atoms of R ¹ and R ² , specifically, a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a t-butyl group, and a phenyl group. , benzyl, naphthyl, methylphenyl, biphenyl, and the like.

The two NH-based amininolide groups attached to the triazine are 4-aminoanilino or 3-aminoanilino, which may be the same or different, and are preferably 4-aminoanilino.

The diamine compound represented by the above formula having a triazine nucleus, specifically, 2,4-bis(4-aminoanilino)-6-anilino-1,3,5-triazine, 2 ,4-bis(3-aminoanilino)-6-anilino-1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-benzylamino-1,3 ,5-triazine, 2,4-bis(3-aminoanilino)-6-benzylamino-1,3,5-triazine, 2,4-bis(4-aminoanilino)-6 -naphthylamino-1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-benzidine- 1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-diphenylamino-1,3,5-triazine, 2,4-bis(3-aminoanilino) )-6-diphenylamino-1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-dibenzylamino-1,3,5-triazine, 2,4 - bis(4-aminoanilino)-6-dinaphthylamino-1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-N-methylanilino- 1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-N-methylnaphthylamino-1,3,5-triazine, 2,4-bis(4- Aminoanilino)-6-methylamino-1,3,5-triazine, 2,4-bis(3-aminoanilino)-6-methylamino-1,3,5-triazine, 2,4,-bis(4-aminoanilino)-6-ethylamino-1,3,5-triazine, 2,4-bis(3-aminoanilino)-6-ethylamino- 1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-dimethylamino-1,3,5-triazine, 2,4-bis(3-aminoaniline -6-dimethylamino-1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-diethylamino-1,3,5-triazine, 2 , 4-bis(4-aminoanilino)-6-dibutylamino-1,3,5-triazine, 2,4-bis(4-aminoanilino)-6-amino-1, 3,5-triazine, 2,4-bis(3-aminoanilino)-6-amino-1,3,5-triazine, and the like.

The isocyanate of the diamine derivative may, for example, be a diisocyanate obtained by reacting the above aromatic or aliphatic diamine with phosgene.

Further, other diamine derivatives may also be exemplified by diaminodioxane, for example, an aromatic or aliphatic alkylated alkyl group obtained by reacting the above aromatic or aliphatic diamine with chlorotrimethylnonane. Diamine.

The diamine is preferably 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl from the viewpoint of excellent transparency and heat correction by heat shrinkage.

The above diamine and its derivative may be used arbitrarily, and the amount of the diamine in the above is preferably 50 to 100 mol%, and 80 to 100 mol. % is preferred.

(1.1.3) Synthesis of polyglycine and oxime imidization (1.1.3.1) Synthesis of polyaminic acid

Polylysine can be obtained by polymerizing at least one of the above-mentioned tetracarboxylic acids and at least one of the above-mentioned diamines in a suitable solvent.

Further, the polyphthalate may be subjected to ring-opening and diesterification of the tetracarboxylic dianhydride by using an alcohol such as methanol, ethanol, isopropanol or n-propanol to prepare the obtained diester appropriately. The solvent is obtained by reacting with the aforementioned diamine compound. Further, the polyphthalate ester can also be obtained by esterifying a carboxyl group of a polyproline which is obtained as described above and an alcohol as described above.

The reaction between the tetracarboxylic dianhydride and the diamine compound can be carried out in accordance with conventionally known conditions. The order of addition or the addition of the tetracarboxylic dianhydride and the diamine compound is not particularly limited. For example, polyglycine can be obtained by sequentially adding tetracarboxylic dianhydride and a diamine compound to a solvent and stirring at a suitable temperature.

The amount of the diamine compound is usually 0.8 mol or more, preferably 1 mol or more, based on 1 mol of the tetracarboxylic dianhydride. On the other hand, it is usually 1.2 m or less, preferably 1.1 m or less. By setting the amount of the diamine compound in such a range, the yield of the obtained polylysine can be increased.

The concentration of the tetracarboxylic dianhydride and the diamine compound in the solvent can be appropriately set depending on the reaction conditions or the viscosity of the polyaminic acid solution. For example, the total mass of the tetracarboxylic dianhydride and the diamine compound is not particularly limited. The total amount of the solution is usually 1% by mass or more, preferably 5% by mass or more, and is usually 70% by mass or less, preferably 30% by mass or less. By setting the amount of the reaction substrate in such a range, polylysine can be obtained at low cost and in good yield.

The reaction temperature is not particularly limited, but is usually 0 ° C or higher, preferably 20 ° C or higher, and is usually 100 ° C or lower, preferably 80 ° C or lower. The reaction time is not particularly limited, but is usually 1 hour or longer, preferably 2 hours or longer, and is usually 100 hours or shorter, preferably 24 hours or shorter. By carrying out the reaction under such conditions, polylysine can be obtained at low cost and in good yield.

The polymerization solvent to be used in the reaction may, for example, be a hydrocarbon solvent such as hexane, cyclohexane, heptane, benzene, toluene, xylene or mesitylene; carbon tetrachloride, dichloromethane, chloroform or 1, Halogenated hydrocarbon solvent such as 2-dichloroethane, chlorobenzene, dichlorobenzene and fluorobenzene; ether solvent such as diethyl ether, tetrahydrofuran, 1,4-dioxane and methoxybenzene; acetone and methyl ethyl a ketone solvent such as a ketone; a guanamine solvent such as N,N-dimethylformamide, N,N-dimethylacetamide or N-methyl-2-pyrrolidone; An aprotic polar solvent such as γ-butyrolactone; a heterocyclic solvent such as pyridine, pyridyl, lutidine, quinoline or isoquinoline; a phenolic solvent such as phenol or cresol, etc. Specially limited. The polymerization solvent may be used singly or in combination of two or more solvents.

The terminal group of the polyamic acid can be arbitrarily selected from the acid group and the amine group by using any of the tetracarboxylic dianhydride and the diamine compound in excess during the polymerization reaction.

In the case where the terminal group is an acid anhydride terminal, the acid anhydride terminal state may be maintained without subsequent treatment, or may be hydrolyzed to a dicarboxylic acid. Further, an ester can be produced by using an alcohol having 4 or less carbon atoms. Further, a monofunctional amine compound or an isocyanate compound may also be used to block the ends. The amine compound or the isocyanate compound used herein can be used as long as it is a monofunctional primary amine compound or an isocyanate compound, and is not particularly limited. For example, aniline, methylaniline, dimethylaniline, trimethylaniline, ethylaniline, diethylaniline, triethylaniline, aminophenol, methoxyaniline, amine benzoic acid, biphenylamine, naphthalene Alkylamine, cyclohexylamine, phenylisocyanate, benzodimethylisocyanate, cyclohexyl isocyanate, methylphenylisocyanate, trifluoromethylphenylisocyanate, and the like.

Further, in the case where the terminal group is an amine terminal, the terminal amine group is blocked by a monofunctional acid anhydride, and the amine group can be prevented from remaining at the terminal end. The acid anhydride used herein can be used as long as it is a monofunctional acid anhydride of a dicarboxylic acid or a tricarboxylic acid, and is not particularly limited. For example, maleic anhydride, methyl maleic anhydride, dimethyl maleic anhydride, succinic anhydride, norbornene dicarboxylic anhydride, 4-(phenylethynyl)phthalic anhydride, 4-ethynylphthalic anhydride, phthalic anhydride , methyl phthalic anhydride, dimethyl phthalic anhydride, trimellitic anhydride, naphthalic anhydride, 7-oxabicyclo[2.2.1] heptane-2,3-dicarboxylic anhydride, bicyclo [2.2.1] g Alkane-2,3-dicarboxylic anhydride, bicyclo[2.2.2]oct-5-ene-2,3-dicarboxylic anhydride, 4-oxatricyclo[5.2.2.0 ^2,6 ]undecane-3, 5-diketone, octahydro-1,3-dioxoisobenzofuran-5-carboxylic acid, hexahydrophthalic anhydride, methyl hexahydrophthalic anhydride, dimethylcyclohexane dicarboxylic anhydride, 1,2 3,6-tetrahydrophthalic anhydride, methyl-4-cyclohexene-1,2-dicarboxylic anhydride, and the like.

(1.1.3.2) oxime imidization

Here, the polyimine can be obtained by heating a poly-proline solution to imidize the polyphosphonium amide (thermal imidization) or adding a closed-loop touch to the poly-proline solution. The medium (an imidization catalyst) is obtained by a method of imidizing polyphosphonium amide (chemical hydrazine imidation method).

Methanation of the film

In the case where a polyamine is used to form a cast film, a polyimide film can be produced by subjecting the obtained film to a ruthenium imidization treatment.

The polyphthalic acid cast film of the present invention is preferably heated stepwise. For example, the solvent is removed by heat treatment, and hydrazine imidization (dehydration ring closure) is carried out to obtain a polyimine.

The heat treatment conditions are not particularly limited, and it is preferably dried at a temperature of from 50 to 150 ° C and from 150 to 250 ° C, and further at a temperature of from 300 to 400 ° C, preferably from 350 to 400 ° C. This is because the ruthenium imidization is promoted by heating at a temperature at which the ruthenium iodide reaction rate is blended and the glass transition temperature of the polyamic acid and the polyamidimide is blended.

In the method for producing a polyimide film of the present invention, a solution obtained by casting a polyphthalic acid containing no ring-closing catalyst into a film may be used, and after heating and drying on the support, the film is supported by the support. Peeling, further drying heat treatment at a high temperature, and hydrazine imidization (thermal imidization method). In addition, in the case of using this method, by allowing the polyaminic acid solution to contain a dehydrating agent, the reaction rate of the ruthenium iodide can be increased, but Aqueous agents are preferred. By not containing a dehydrating agent, the durability of the polyimide film caused by the residual dehydrating agent can be suppressed from being lowered.

Among the thermal imidization methods, heat treatment can be performed by using, for example, an infrared heater. In the infrared heater, for example, the heater body may be formed by enclosing the heating wire with an inner tube which is covered by the outer tube, and the cooling fluid may flow between the heater body and the outer tube to form a heater. The heating wire is heated to 700 to 1200 ° C by electric current, and emits infrared rays having a peak near the wavelength of 3 μm. The inner tube and the outer tube are made of quartz glass or bismuth borosilicate glass, and have a function of penetrating infrared rays having a wavelength of 3.5 μm or less and absorbing infrared rays having a wavelength exceeding 3.5 μm. In such an infrared heater, when infrared rays having a peak near a wavelength of 3 μm are emitted from the heating wire, infrared rays having a wavelength of 3.5 μm or less penetrate the inner tube or the outer tube and are irradiated to the film. By irradiating infrared rays of this wavelength, the mixed solvent in the film can be efficiently evaporated, and the polyamine acid in the film can be imidized. Further, the inner tube or the outer tube absorbs infrared rays having a wavelength of more than 3.5 μm and is cooled by the cooling fluid passing through the flow path, so that the temperature can be maintained at a point of ignition that does not reach the mixed solvent evaporated by the film.

Alternatively, it may be formed into a film by casting a solution of polyamic acid containing a ring-closing catalyst and a dehydrating agent, and a part of the support may be imidized on the support to form a film, and then the film may be peeled off by the support and heated. Drying / hydrazine imidization, heat treatment (chemical hydrazine imidation method). Specific examples of the closed-loop catalyst include aliphatic tertiary amines such as trimethylamine and triethylenediamine, and heterocyclic tertiary amines such as isoquinoline, pyridine, and methylpyridine. At least one amine from a heterocyclic tertiary amine. The content of the closed-loop catalyst relative to the poly-proline is preferably in the range of 0.5 to 8.0 of the content of the closed-loop catalyst (mole) / poly-proline (mol).

Further, in the case of this method, by allowing the polyaminic acid solution to contain a dehydrating agent, the imidization can be carried out at a low temperature, so that the durability of the polyimide film can be suppressed from being lowered.

In addition, a method of heating a polylysine solution to imidize polyphosphonium amide (thermal imidization method), or adding a ring-closing catalyst to a polyamid acid solution (an imide catalyst) The method for imidating polyphosphonium amide (chemical hydrazine imidation method) is not limited to the above cast film, and for example, a reaction vessel in which polyamic acid is polymerized from an acid anhydride and a diamine can be directly used. The oxime was imidized in a reaction kettle.

In the thermal hydrazine imidation method carried out in the reaction vessel, the polyglycine in the polymerization solvent is heat-treated, for example, at a temperature of 80 to 300 ° C for 0.1 to 200 hours to carry out hydrazine imidization. In addition, it is preferable to set the above temperature range to 150 to 200 ° C. By setting it at 150 ° C or higher, the ruthenium imidization can be surely carried out and finished. On the other hand, by setting the temperature below 200 ° C, the solvent or the solvent can be prevented. The concentration of the resin due to oxidation of the unreacted raw material and solvent evaporation increases.

Further, among the thermal imidization methods, in order to efficiently remove water generated by the hydrazine imidization reaction, an azeotropic solvent may be added to the above polymerization solvent. As the azeotropic solvent, for example, an aromatic hydrocarbon such as toluene, xylene or solvent oil, or an alicyclic hydrocarbon such as cyclohexane, methylcyclohexane or dimethylcyclohexane can be used. In the case of using an azeotropic solvent, the amount added is organic The total amount of the solvent is about 1 to 30% by mass, preferably 5 to 20% by mass.

On the other hand, in the chemical hydrazine imidation method, a well-known ring-closing catalyst is added to the polyphthalic acid in the above-mentioned polymerization solvent, and ruthenium imidization is carried out. Specific examples of the ring-closing catalyst include aliphatic tertiary amines such as trimethylamine and triethylenediamine, and heterocyclic tertiary amines such as isoquinoline, pyridine and methylpyridine. Other examples include substitution or non- a substituted nitrogen-containing heterocyclic compound, an N-site oxide compound of a nitrogen-containing heterocyclic compound, a substituted or unsubstituted amino acid compound, an aromatic hydrocarbon compound having a hydroxyl group or an aromatic heterocyclic compound, and particularly suitable for use 1, 2-dimethylimidazole, N-methylimidazole, N-benzyl-2-methylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 5-methylbenzimidazole, etc. Imidazole derivatives such as lower alkyl imidazole, N-benzyl-2-methylimidazole, isoquinoline, 3,5-lutidine, 3,4-dimethylpyridine, 2,5-dimethyl Substituted pyridine such as pyridine, 2,4-dimethylpyridine or 4-n-propylpyridine, p-toluenesulfonic acid or the like. The amount of the closed-loop catalyst added is 0.01 to 2 equivalents, and particularly preferably about 0.02 to 1 equivalent, relative to the unit of the proline acid. By using a closed-loop catalyst, it is possible to enhance the physical properties of the obtained polyimine, especially in the case of elongation or rupture resistance.

In addition, a dehydrating agent may be added to the polyaminic acid solution, and the dehydrating agent may, for example, be an aliphatic acid anhydride such as acetic anhydride or hydrazine. An aromatic acid anhydride such as an acid anhydride or the like may be used singly or in combination. Further, if a dehydrating agent is used, the reaction can be carried out at a low temperature, which is suitable. In addition, even if a dehydrating agent is added only to the polyaminic acid solution, although the polyaminic acid can be arniminated, the reaction rate is slow, so it is preferable to heat or add as described above. The ring-closing catalyst is added to carry out the oxime imidization.

As described above, the polyimine solution in which the oxime imidization is carried out in the reaction vessel is less likely to cause a decrease in molecular weight due to time-lapse hydrolysis, which is advantageous.

Further, since the ruthenium imidization reaction is carried out in advance, for example, in the case of a polyimide having a ruthenium iodide ratio of 100%, it is not necessary to carry out hydrazine imidization in a cast film or a film, and the drying temperature can be lowered.

Alternatively, the closed-loop polyimine may be reprecipitated and purified using a poor solvent or the like to form a solid, which is then dissolved in a solvent, cast, and dried to form a film.

According to this method, by setting the polymerization solvent and the solvent to be different, and selecting the most suitable solvent, the performance of the polyimide film can be exhibited.

For example, in order to polymerize polylysine, it is polymerized by using dimethylacetamide, closed-loop, and solidified by using methanol. After drying, it is solutionized with dichloromethane, then cast and dried. Perform high molecular weight and low temperature drying.

Further, in the case where the solvent is dichloromethane, it can be used in combination with other solvents. A solvent may be suitably used, such as tetrahydrofuran (THF), dioxolane, cyclohexanone, cyclopentanone, γ-butyrolactone, ethanol, methanol, butanol, isopropanol or the like.

In addition, the polyaminic acid can be imidized at the time of casting, and the yield of hydrazine imidation during casting is preferably from 10 to 100%. Here, the ruthenium amination rate can be determined by 1H-NMR spectroscopy, and the ruthenium can be determined. rate.

In the method for producing a polyimide film of the present invention, any of the above closed-loop methods may be employed, however, from the viewpoint of less residue in the polyimide reaction solution and lowering the film formation temperature, A method in which a hot hydrazide polyimide solution in a reaction vessel is cast on a support is a preferred method.

(1.1.4) Other polyimine

In addition to the above polyimine, a polyimine containing an atom such as phosphorus, hydrazine, sulfur or the like can also be used.

For example, the polyimine containing phosphorus can be used in paragraphs [0010] to [0021] of JP-A-2011-74209 and paragraphs [0011] to [0025] of JP-A-2011-074177, respectively. Polyimine.

The polyimine containing ruthenium may be obtained by imidating a polyimine precursor ruthenium described in paragraphs [0030] to [0045] of JP-A-2013-028796.

For the sulfur-containing polyimine, paragraphs [0009] to [0025] of JP-A-2010-189322, paragraphs [0012] to [0025] of JP-A-2008-274234, and Japan can be used. JP-A-2008-274229 [0023] A polyimine obtained by imidating a polyimine precursor ruthenium.

Other paragraphs of [0008] to [0012] and JP-A-2009-256589 of JP-A-2009-256590 are also suitable. The alicyclic polyimine and the like described in [0008] to [0012].

(1.2) Polyamidimide

The polyamidoximine used in the present invention is a polyamidoximine containing a tricarboxylic acid or a tetracarboxylic acid, a dicarboxylic acid as an acid component, and a diamine as an amine component in a structural unit.

In the polyamidoximine used, the acid component is

a) Tricarboxylic acid: diphenyl ether-3,3',4'-tricarboxylic acid, diphenylguanidin-3,3',4'-tricarboxylic acid, benzophenone-3,3',4'- A single or a mixture of two or more of a monoanhydride or an esterified product such as a tricarboxylic acid such as a tricarboxylic acid, a naphthalene-1,2,4-tricarboxylic acid or a butane-1,2,4-tricarboxylic acid.

b) tetracarboxylic acid: diphenyl hydrazine-3,3',4,4'-tetracarboxylic acid, naphthalene-2,3,6,7-tetracarboxylic acid, naphthalene-1,2,4,5-tetracarboxylic acid Acid, naphthalene-1,4,5,8-tetracarboxylic acid, butane-1,2,3,4-tetracarboxylic acid, cyclopentane-1,2,3,4-tetracarboxylic acid monoanhydride, two A single or a mixture of two or more of an anhydride, an esterified product or the like.

c) Dicarboxylic acid: a dicarboxylic acid such as adipic acid, sebacic acid, sebacic acid or cyclohexane-4,4'-dicarboxylic acid, and such monoanhydride or esterified product.

Amine component

d) Amine component

Examples thereof include 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-diethyl-4,4'-diaminobiphenyl, 2,2'--dimethyl 4-,4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diamine Biphenyl, 3,3'-diethoxy-4,4'-diaminobiphenyl, p-phenylenediamine, m-phenylenediamine, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl hydrazine, 3,3'-diaminodiphenyl hydrazine, 3, 4'-Diaminobiphenyl, 3,3'-diaminobiphenyl, 3,3'-diaminobenzimidamide, 4,4'-diaminobenzimidamide, 4,4' -diaminobenzophenone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 2,6-toluenediamine, 2,4-toluenediamine, 4, 4'-Diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenylpropane, 3,3'-diaminodiphenyl Propane, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, p-xylenediamine, m-xylenediamine, 2,2'-bis(4-amine Phenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy) Benzo, 2,2-bis[4-(4-aminophenoxy)phenyl]propane, bis[4-(4-aminophenoxy)phenyl]anthracene, bis[4-(3 -aminophenoxy)phenyl]indole, bis[4-(3-aminophenoxy)phenyl]propane, 4,4'-bis(4-aminophenoxy)biphenyl, 4, 4'-bis(3-aminophenoxy)biphenyl, tetramethylenediamine, hexamethylenediamine, isophoronediamine, 4,4'-bicyclo Methane diamine, cyclohexane-1,4-diamine, siloxane diamine silicon, alone or in connection with a corresponding or a mixture of two or more diisocyanates.

In particular, it is preferred to contain trimellitic anhydride (TMA), 3,3,4',4'-benzophenonetetracarboxylic dianhydride (BTDA) and 3,3,4',4'-biphenyltetracarboxylic acid. A dianhydride (BPDA) is an acid component and contains 1,5-naphthalene diisocyanate (NDI) as a polyamidoximine resin polymerized as a raw material of an isocyanate component.

The molar ratio of the ruthenium imine bound to the guanamine is preferably from 99/1 to 60/40, preferably from 99/1 to 75/25, more preferably 90. /10~80/20. When the molar ratio of the quinone bond and the guanamine bond is 60/40 or more, heat resistance, moisture resistance, and heat resistance are satisfied. Upgrade. In addition, when it is 99/1 or less, the modulus of elasticity tends to be low, and the folding resistance and the bending property tend to be improved.

(1.2.1) Polyamidoquinone imine which is an essential component of the structure represented by formula (2)

One of the suitable embodiments is that the structure represented by the formula (2) is an essential component, and further contains at least a group selected from the group consisting of the formula (3), the formula (4), and the formula (5) in the molecular chain. One type of structure is a polyamidoquinone imine resin as a repeating unit.

(X represents an oxygen atom, CO, SO ₂ or bond, and n represents 0 or 1)

(Y represents an oxygen atom, CO, or OOC-R-COO, n represents 0 or 1, and R represents a divalent organic group)

Here, in the formula (3), X is preferably SO ₂ or a bond (biphenyl bond) or n = 0, more preferably a bond (biphenyl bond) or n = 0. In the formula (4), Y is preferably a benzophenone type (CO) or a bonded type (biphenyl bond).

In one suitable embodiment, the formula (2) is a repeating unit derived from trimellitic anhydride and 1,5-naphthalene diisocyanate, and the formula (3) is derived from terephthalic acid and 1,5-naphthalene diisocyanate. The repeating unit, formula (4) is a repeating unit derived from biphenyltetracarboxylic dianhydride or benzophenone tetracarboxylic dianhydride and 1,5-naphthalene diisocyanate, and the content thereof is preferably a formula (2) / { (3) The molar ratio of + (4) + (5)} = 1 / 99 ~ 40 / 60, and the formula (3) / formula (4) = 10 / 90 ~ 90/10 Moerby.

The higher the yield of hydrazine, the better, the upper limit is 100%. The above polyamidoximine resin can be synthesized by a usual method. For example, an isocyanate method, an amine method (an oxime method, a low-temperature solution polymerization method, a room temperature solution polymerization method, etc.), etc., the polyamidoximine resin used in the present invention is preferably soluble in an organic solvent, as described above, It is preferable to use the isocyanate method for the reason of ensuring the reliability of the peel strength (follow strength) and the like. Further, industrially, the solution at the time of polymerization can be directly coated, which is suitable.

(1.2.2) Polyamidoquinone imine having the structure represented by formula (6) or (7)

As the suitable polyamidoximine resin, a compound containing the following formula (6) as a structural unit is suitably used. A compound having a structure represented by the following formula (6) will be described.

(wherein R ₁ may also contain an aromatic group, a cycloalkyl group, a nitrogen, an oxygen, a sulfur or a halogen) (a diamine component of a polyamidoximine resin)

In addition, as the diamine component, p-phenylenediamine, m-phenylenediamine, 3,4- can be used. Diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl hydrazine, 3,3'-diaminodiphenyl hydrazine, 3,4'-diamine Biphenyl, 3,3'-diaminobiphenyl, 3,3'-diaminobenzimidamide, 4,4'-diaminobenzimidamide, 4,4'-diaminodi Benzophenone, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone, 2,6-toluenediamine, 2,4-toluenediamine, 4,4'-diamine Diphenyl sulfide, 3,3'-diaminodiphenyl sulfide, 4,4'-diaminodiphenylpropane, 3,3'-diaminodiphenylpropane, 3,3 '-Diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, p-xylenediamine, m-xylenediamine, 1,4-naphthalenediamine, 1,5-naphthalenediamine , 2,6-naphthalenediamine, 2,7-naphthalenediamine, 2,2'-bis(4-aminophenyl)propane, 1,3-bis(3-aminophenoxy)benzene, 1 , 3-bis(4-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 2,2-bis[4-(4-aminophenoxy)phenyl Propane, bis[4-(4-aminophenoxy)phenyl]indole, bis[4-(3-aminophenoxy)phenyl]indole, bis[4-(3-aminophenoxy) Phenyl]propane, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, 3,3'-dimethyl base -4,4'-diaminobiphenyl, 4-methyl-1,3-phenylenediamine, 3,3'-diethyl-4,4'-diaminobiphenyl, 2,2'- Dimethyl-4',4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4' -diaminobiphenyl, 3,3'-diethoxy-4,4'-diaminobiphenyl, trans-1,4-diaminocyclohexane, cis-1,4-diamine Cyclohexane, 1,4-diaminocyclohexane (reverse/cis mixture), 1,3-diaminocyclohexane, dicyclohexylmethane-4,4'-diamine (antibody, cis , reverse/cis mixture), isophorone diamine, 1,4-cyclohexane bis(methylamine), 2,5-bis(aminomethyl)bicyclo[2.2.1]heptane, 2,6- Bis(aminomethyl)bicyclo[2.2.1]heptane, 3,8-bis(aminomethyl)tricyclo[5.2.1.0]decane, 1,3-diamine, adamantane, 4,4'- Methylene bis(2-methylcyclohexylamine), 4,4'-methylene bis(2-ethyl ring Hexylamine), 4,4'-methylenebis(2,6-dimethylcyclohexylamine), 4,4'-methylenebis(2,6-diethylcyclohexylamine), 2, 2-bis(4-aminocyclohexyl)propane, 2,2-bis(4-aminocyclohexyl)hexafluoropropane, 1,3-propanediamine, 1,4-tetramethylenediamine, 1 , 5-pentamethylenediamine, 1,6-hexamethylenediamine, 1,7-heptamethylenediamine, 1,8-octamethylenediamine, 1,9-九亚甲As the diamine component, a single or a mixture of two or more kinds of bis-diamine or the like, or a mixture of two or more kinds of diisocyanate or the like may be used.

Suitable for the use of 3,3'-dimethyl-4,4'-diaminobiphenyl, dicyclohexylmethane-4,4'-diamine (transverse, cis, trans/cis mixture), 4, a single or a mixture of two or more of 4'-diaminodiphenyl ether, p-phenylenediamine, 4-methyl-1,3-phenylenediamine, or the like, or two or more of the corresponding diisocyanates The above mixture is used as the diamine component.

It is more suitable to use 3,3'-dimethyl-4,4'-diaminobiphenyl, dicyclohexylmethane-4,4'-diamine (transverse, cis, trans/cis mixture), 4, a single or a mixture of two or more of 4'-diaminodiphenyl ether and 4-methyl-1,3-phenylenediamine, or a mixture of two or more of these corresponding diisocyanates or the like Diamine component.

More suitable for the use of 3,3'-dimethyl-4,4'-diaminobiphenyl, dicyclohexylmethane-4,4'-diamine (transverse, cis, trans/cis mixture), 4- A single or a mixture of two or more kinds of methyl-1,3-phenylenediamine or a mixture of two or more of these corresponding diisocyanates may be used as the diamine component.

(suitable combination of acid component and diamine component)

From the viewpoints of heat resistance, solvent resistance, durability, and heat resistance, surface smoothness, and transparency of the produced polyimide film, in the above-mentioned acid component, Among the diamine components, the following components are suitably used.

As the acid component, cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride can be used. A polyamidoximine resin having an acid component of cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride can be used.

As the diamine component, at least one selected from the group consisting of 3,3'-dimethyl-4,4'-diaminobiphenyl and 4-methyl-1,3-phenylenediamine may be used. Kind of compound, or selected from 3,3'-dimethyl-4,4'-diisocyanate biphenyl (o-tolidine diisocyanate), and 4-methyl-1,3-benzene diisocyanate (toluene) At least one or two compounds of the group consisting of isocyanate).

Further, as the suitable polyamidoximine resin, a compound containing a structure represented by the following formula (7) as a structural unit can be used.

(wherein R ₂ and R ₃ are each independently hydrogen, an alkyl group having 1 to 3 carbon atoms, or an aromatic group, and may also contain nitrogen, oxygen, sulfur, or halogen)

Further, when the total acid component is set to 100 mol%, the exemplified acid component preferably contains 50 mol% or more and 100% or less, preferably 70 mol%. Above 100%. Further, when the total diamine component is set to 100 mol%, the diamine component exemplified preferably contains 50 mol% or more and 100% or less, and preferably contains 70 mol% or more and 100% or less. In such a range, the heat resistance and durability in the film formation process are good, and the heat resistance, surface smoothness, and transparency of the obtained polyimide film are particularly excellent.

The molecular weight of the polyamidoximine resin used is preferably equivalent to that in N-methyl-2-pyrrolidone (polymer concentration: 0.5 g/cm ³ ) and a logarithmic viscosity of from 0.3 to 2.5 cm at 30 ° C. The molecular weight of ³ / g is preferably a molecular weight equivalent to 0.5 to 2.0 cm ³ /g. When the logarithmic viscosity is 0.3 cm ³ /g or more, mechanical properties are sufficient when a molded article such as a film is formed. On the other hand, when it is 2.0 cm ³ /g or less, the viscosity of the solution does not become too high, and the molding process is easy to proceed.

(1.3) Polyether quinone

The polyether sulfimine used in the present invention has a thermoplastic resin containing an aromatic nucleus bond and a quinone imine bond in the structural unit, and is not particularly limited, and specifically, it is preferably having the following formula (8) or A polyether quinone imine of a repeating unit of the structure represented by the following formula (9).

The polyether phthalimide having a repeating unit having the structure represented by the above formula (8) includes a product name "Ultem 1000" manufactured by General Electric Co., Ltd. (glass transition temperature: 216 ° C), and "Ultem 1010" (glass transition temperature). 216 ° C), the polyether sulfimine having a repeating unit of the structure represented by the above formula (9), "Ultem CRS5001" (glass transition temperature Tg is 226 ° C), and other specific examples include Mitsui Chemicals The product name "Aurum PL500AM" (glass transition temperature 258 ° C) manufactured by the company.

The method for producing the polyether sulfimine is not particularly limited. Usually, the amorphous polyether sulfimine having the structure represented by the above formula (8) is 4,4'-[isopropylidene double (pair) a polycondensate of phenyloxy)]diphthalic acid dianhydride and m-phenylenediamine, and the polyether sulfimine having the structure represented by the above structural formula (9) is 4,4'-[sub-different A polycondensate of propylbis(p-phenyleneoxy)]diphthalic acid dianhydride and p-phenylenediamine is synthesized by a known method.

Further, the polyetherimine may further contain other monomer units copolymerizable such as a mercapto group, an ester group or a sulfonyl group, within a range not exceeding the gist of the present invention. Further, the polyether oximine may be used alone or in combination of two or more.

(1.4) Polyester quinone

The resin having the quinone imine structure used in the present invention preferably contains a polyester quinone imine structure represented by the formula (10).

(In the formula (10), R ₁ represents a divalent group having a specific structure, and R ² represents a divalent chain aliphatic group, a divalent cyclic aliphatic group or a divalent aromatic group)

In the formula (10), R ₁ represents a divalent group each having a structure represented by the formula (11), the formula (12) or the formula (13).

(having a divalent group of the structure represented by the formula (11))

In the formula (11), R represents each divalent chain aliphatic group, cyclic aliphatic group or aromatic group, and a plurality of R's may be the same or different. These chain aliphatic groups, cyclic aliphatic groups or aromatic groups may be used singly or in combination of two or more.

m is a positive integer of 1 or more, preferably 2 or more, 3 or more is preferable, and 4 or more is more preferable. Further, the upper limit of m is not particularly limited, but is preferably 25 or less, preferably 20 or less, more preferably 10 or less. When it exceeds 25, heat resistance tends to fall.

The chain aliphatic group, the cyclic aliphatic group or the aromatic group is desirably "chain aliphatic compound having a divalent hydroxyl group", "cyclic aliphatic compound having a divalent hydroxyl group" or "having a divalent value" Residue derived from a diol such as a hydroxy aromatic compound. Further, it may be a residue derived from a "polycarbonate diol" obtained by polymerizing the diol, a carbonate, or phosgene.

As the "chain aliphatic compound having a divalent hydroxyl group", a branched or linear diol having two hydroxyl groups can be used. For example, an alkylene glycol, a polyoxyalkylene glycol, a polyester diol, a polycaprolactone diol, etc. are mentioned. A branched or linear diol having two hydroxyl groups which can be used as a "chain aliphatic compound having a divalent hydroxyl group" is exemplified as follows.

The alkylene glycol may, for example, be ethylene glycol or diethylene glycol. Alcohol, propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 3-methyl-1,5-pentanediol, 1,6- Hexanediol, 1,8-octanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-nonanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol or the like.

The polyoxyalkylene glycol may, for example, be dimethylolpropionic acid (2,2-bis(hydroxymethyl)propionic acid) or dimethylolbutanoic acid (2,2-bis(hydroxymethyl)butane. Acid), polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxytetramethylene glycol, random copolymer of tetramethylene glycol and neopentyl glycol, and the like. It is preferably polyoxytetramethylene glycol.

Examples of the polyester diol include a polyester diol obtained by reacting a polyhydric alcohol exemplified below with a polybasic acid.

As the "polyol component" used in the polyester diol, various polyols can be used arbitrarily. For example, ethylene glycol, propylene glycol, 1,3-propanediol, 2-methyl-1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, diethylene glycol, dipropylene glycol, 2,2,4-trimethyl Base-1,3-pentanediol, cyclohexanemethanol, neopentylhydroxy-t-valerate, ethylene oxide adduct of bisphenol A, propylene oxide adduct, hydrogenated bisphenol A ring Oxyethane adduct and propylene oxide adduct, 1,9-nonanediol, 2-methyloctanediol, 1,10-dodecanediol, 2-butyl-2-ethyl- A polyether polyol such as 1,3-propanediol, tricyclodecane methanol, polyethylene glycol, polypropylene glycol or polytetramethylene glycol.

Any of various polybasic acids can be used as the "polybasic acid component" used in the polyester diol. For example, terephthalic acid, isophthalic acid, Phthalic acid, 1,5-naphthalene dicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 4,4'-diphenyldicarboxylic acid, 2,2'-diphenyldicarboxylic acid, 4,4'- Diphenyl ether dicarboxylic acid, adipic acid, sebacic acid, sebacic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylate An aliphatic or alicyclic dibasic acid such as an acid, 4-methyl-1,2-cyclohexanedicarboxylic acid or a dimer acid.

Specific examples of the commercial product of the polyester diol include ODX-688 (aliphatic polyester diol manufactured by DIC Corporation: adipic acid/neopentyl glycol/1,6-hexanediol, amount The average molecular weight is about 2,000), Vylon (registered trademark) 220 (polyester diol manufactured by Toyobo Co., Ltd., number average molecular weight: about 2,000), and the like.

Examples of the polycaprolactone diol include polycaprolactone diol obtained by subjecting a lactone such as γ-butyrolactone, ε-caprolactone, or δ-valerolactone to a ring-opening addition reaction.

The above-mentioned "chain aliphatic compound having a divalent hydroxyl group" may be used singly or in combination of two or more.

"A cyclic aliphatic compound having a divalent hydroxyl group" or "an aromatic compound having a divalent hydroxyl group", "a compound having two hydroxyl groups in an aromatic ring or a cyclohexane ring", "two phenols or an alicyclic ring" can be used. A compound in which a phenol is bonded by a divalent functional group, a "compound having a hydroxyl group in each of two cores of a biphenyl structure", and a "compound having two hydroxyl groups in a naphthalene skeleton".

"A compound having two hydroxyl groups in an aromatic ring or a cyclohexane ring", hydroquinone, 2-methylhydroquinone, resorcinol, catechol, 2-phenylhydroquinone, cyclohexanedimethanol can be used. , tricyclodecane methanol, 1,4-dihydroxy ring Hexane, 1,3-dihydroxycyclohexane, 1,2-dihydroxycyclohexane, 1,3-adamantanediol, dicyclopentadiene dihydrate, 2,3-dihydroxybenzoic acid a carboxyl group-containing, 2,4-dihydroxybenzoic acid, 2,5-dihydroxybenzoic acid, 2,6-dihydroxybenzoic acid, 3,4-dihydroxybenzoic acid, 3,5-dihydroxybenzoic acid, etc. Glycol and the like.

Examples of "two phenols" or "compounds in which an alicyclic alcohol is bonded by a divalent functional group" may be 4,4'-dihydroxydiphenyl ether or 4,4'-dihydroxydiphenyl hydrazine or 4, 4'-(9-fluorenylene)diphenol, 4,4'-dihydroxydicyclohexyl ether, 4,4'-dihydroxydicyclohexylfluorene, bisphenol A, bisphenol F, hydrogenated bisphenol A, Hydrogenated bisphenol F and the like.

Further, as an example of "a compound in which two cores of a biphenyl structure have one hydroxyl group", 4,4'-biphenol, 3,4'-biphenol, 2,2'-biphenyl may be used. Phenol, 3,3',5,5'-tetramethyl-4,4'-biphenyldiol, and the like.

Examples of the "compound having two hydroxyl groups in the naphthalene skeleton" include 2,6-naphthalenediol, 1,4-naphthalenediol, 1,5-naphthalenediol, 1,8-naphthalenediol, and the like.

The number average molecular weight of the diol is preferably 100 or more and 30,000 or less, preferably 150 or more and 20,000 or less, more preferably 200 or more and 10,000 or less. When the number average molecular weight is less than 100, the low moisture absorption property and the flexibility are not exhibited, and if it is more than 30,000, the composition and structure of the "diol" cannot be used, and the diamine component described later (or The composition and structure of the isocyanate component are sufficient to exhibit phase separation, mechanical properties, and colorless transparency.

The polycarbonate diol may have the above various alkylenes in the skeleton Base polycarbonate diol (copolymerized polycarbonate diol). For example, a combination of 2-methyl-1,8-octanediol and 1,9-nonanediol, a combination of 3-methyl-1,5-pentanediol and 1,6-hexanediol can be cited, A copolymerized polycarbonate diol synthesized by a combination of 1,5-pentanediol and 1,6-hexanediol or the like. It is preferably a copolymerized polycarbonate diol which can be synthesized from a combination of 2-methyl-1,8-octanediol and 1,9-nonanediol. These polycarbonate diols may be used in combination of two or more kinds.

Commercially available products of polycarbonate diols include Kuraray Polyol C series manufactured by KURARAY Co., Ltd., and DURANOL series of Asahi Kasei Chemicals Co., Ltd., and the like. For example, Kuraray Polyol C-1015N, Kuraray Polyol C-1065N (carbonate diol manufactured by KURARAY Co., Ltd.: 2-methyl-1,8-octanediol/1,9-nonanediol, number average molecular weight) About 1000), Kuraray Polyol C-2015N, Kuraray Polyol C2065N (carbonate diol manufactured by KURARAY Co., Ltd.: 2-methyl-1,8-octanediol/1,9-nonanediol, number average molecular weight about 2000), Kuraray Polyol C-1050, Kuraray Polyol C-1090 (carbonate diol manufactured by KURARAY Co., Ltd.: 3-methyl-1,5-pentanediol/1,6-hexanediol, number average molecular weight About 1000), Kuraray Polyol C-2050, Kuraray Polyol C-2090 (carbonate diol manufactured by KURARAY Co., Ltd.: 3-methyl-1,5-pentanediol/1,6-hexanediol, average number Molecular weight: about 2000), DURANOL-T5650E (polycarbonate diol manufactured by Asahi Kasei Chemicals Co., Ltd.: 1,5-pentanediol/1,6-hexanediol, number average molecular weight: about 500), DURANOL-T5651 (Asahi Kasei Chemicals Co., Ltd. Polycarbonate diol: 1,5-pentanediol/1,6-hexanediol, number average molecular weight about 1000), DURANOL-T5652 (polycarbonate diol manufactured by Asahi Kasei Chemicals Co., Ltd.: 1,5) - pentanediol / 1,6-hexanediol, a number average molecular weight of about 2,000). Suitable examples are Kuraray Polyol C-1015N and the like.

Examples of the method for producing the polycarbonate diol include transesterification of a raw material diol with a carbonate, and dehydrochlorination of a raw material diol with phosgene. Examples of the carbonate of the raw material include a dialkyl carbonate such as dimethyl carbonate or diethyl carbonate; a diaryl carbonate such as diphenyl carbonate; and an ethylene carbonate or propylene carbonate. Alkyl carbonate.

(having a divalent group of the structure represented by the formula (12))

The description will be given for the divalent group having the structure represented by the formula (12).

In the formula (12), R ₃ represents a direct bond, an alkylene group (-C _n H _2n -), a perfluoroalkylene group (-C _n F _2n -), an ether bond (-O-), an ester bond ( -COO-), carbonyl (-CO-), sulfonyl (-S(=O) ₂ -), sulfinyl (-SO-), thio (-S-), carbonate (-OCOO) -), or Aachen. n is a positive integer of 1 or more. The upper limit of n is not particularly limited, but is preferably 10 or less, preferably 5 or less, and more preferably 3 or less. X ₁ to X ₈ may be the same or different and each represents hydrogen, halogen or alkyl.

Specific examples of the divalent group having the structure represented by the formula (12) include a diphenyl ether skeleton, a diphenylfluorene skeleton, a 9-fluorenylene diphenol skeleton, a bisphenol A skeleton, a bisphenol F skeleton, and a bisphenol. The ethylene oxide adduct skeleton of A, the propylene oxide adduct skeleton of bisphenol A, a biphenyl skeleton, a naphthalene skeleton, and the like are not particularly limited.

The aforementioned skeleton is preferably a residue derived from a compound having one hydroxyl group in each of two benzene rings of the formula (12). As the raw material of the divalent group having the structure represented by the formula (12), 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl hydrazine, 4,4'-(9-Arene) can be used. Diphenyl, bisphenol A, bisphenol F, ethylene oxide adduct of bisphenol A, propylene oxide adduct of bisphenol A, 4,4'-biphenol, 3,4' -biphenyldiol, 2,2'-biphenol, 3,3',5,5'-tetramethyl-4,4'-biphenol, 2,6-naphthalenediol, 1, 4-naphthalenediol, 1,5-naphthalenediol or 1,8-naphthalenediol.

Ethylene oxide adduct of 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl hydrazine, 4,4'-(9-fluorenylene) diol or bisphenol A . More preferably, it is an ethylene oxide adduct of 4,4'-dihydroxydiphenyl ether or bisphenol A.

These compounds may be used singly or in combination of two or more. By using these raw materials, the above-mentioned diphenyl ether skeleton or the like can be introduced at the R ₁ position of the formula (10).

(having a divalent group of the structure represented by the formula (13))

In the formula (13), R ₄ represents a direct bond, an alkylene group (-C _n H _2n -), a perfluoroalkylene group (-C _n F _2n -), an ether bond (-O-), an ester bond ( -COO-), carbonyl (-CO-), sulfonyl (-S(=O) ₂ -), sulfinyl (-SO-), thio (-S-), carbonate (-OCOO) -), or Aachen. n is a positive integer of 1 or more. The upper limit of n is not particularly limited, but is preferably 10 or less, preferably 5 or less, and more preferably 3 or less. X ₁ '~ X _8', respectively, may be the same or different, each represents hydrogen, halogen or alkyl.

Specific examples of the divalent group having the structure represented by the formula (13) include a dicyclohexyl ether skeleton, a dicyclohexylfluorene skeleton, a hydrogenated bisphenol A skeleton, a hydrogenated bisphenol F skeleton, and an epoxy of hydrogenated bisphenol A. The ethane adduct skeleton or the propylene oxide adduct skeleton of hydrogenated bisphenol A is not particularly limited.

The aforementioned skeleton is preferably a residue derived from a compound having one hydroxyl group per two cyclohexane rings of the formula (13). As the raw material of the divalent group having the structure represented by the formula (13), 4,4'-dihydroxydicyclohexyl ether, 4,4'-dihydroxydicyclohexylfluorene, hydrogenated bisphenol A, hydrogenated bisphenol can be used. F, an ethylene oxide adduct of hydrogenated bisphenol A or a propylene oxide adduct of hydrogenated bisphenol A, or the like.

It is preferably 4,4'-dihydroxydicyclohexyl ether or 4,4'-dihydroxydicyclohexyl fluorene.

These compounds may be used singly or in combination of two or more. By using these raw materials, the above-mentioned dicyclohexyl ether skeleton or the like can be introduced at the R ₁ position of the formula (10).

The structure of the formula (10), for example, can react a halide of cyclohexane tricarboxylic anhydride with a glycol to obtain a tetracarboxylic dianhydride containing an ester group, and then the tetracarboxylic dianhydride containing the ester group and A diamine or a diisocyanate is obtained by performing a condensation reaction (polyimidization).

(having a divalent group of the structure represented by the formula (14))

The polyester quinone imine resin may further contain a structure represented by the formula (14) in the structural unit.

R ₂ of the formula (10) and R ₂ ' of the formula (14) will be described. R ₂ and R ₂ ' are not particularly limited as long as they are each independently a divalent chain aliphatic group, a divalent cyclic aliphatic group or a divalent aromatic group. These "bivalent chain aliphatic group", "divalent cyclic aliphatic group", and "divalent aromatic group" may be used singly or in combination of two or more.

R ₂ preferably has a divalent group having a structure represented by the following formula (15), and R ₂ ' preferably has a divalent group having a structure represented by the following formula (16).

(having a divalent group of the structure represented by the formula (15))

From the viewpoint of the balance of heat resistance, flexibility, and low moisture absorption, R ₂ in the above formula (10) preferably has a divalent group of the structure represented by the formula (15).

In the formula (15), R ₅ represents a direct bond, an alkylene group (-C _n H _2n -), a perfluoroalkylene group (-C _n F _2n -), an ether bond (-O-), an ester bond ( -COO-), carbonyl (-CO-), sulfonyl (-S(=O) ₂ -), sulfinyl (-SO-) or thio (-S-). n is preferably a positive integer of 1 or more and 10 or less, preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less. X ₉ ~X ₁₆ may be the same or different and each represents hydrogen, halogen or alkyl.

(having a divalent group of the structure represented by the formula (16))

From the viewpoint of the balance of heat resistance, flexibility, and low moisture absorption, R ₂ ' in the above formula (14) is preferably a divalent group having a structure represented by the formula (16).

In the formula (16), R ₅ ' represents a direct bond, an alkyl group (-C _n H _2n -), a perfluoroalkyl group (-C _n F _2n -), an ether bond (-O-), an ester bond. (-COO-), carbonyl (-CO-), sulfonyl (-S(=O) ₂ -), sulfinyl (-SO-) or thio (-S-). n is preferably a positive integer of 1 or more and 10 or less, preferably 1 or more and 5 or less, more preferably 1 or more and 3 or less. X ₉ '~X ₁₆ ' may be the same or different and each represents hydrogen, halogen or alkyl.

In the formulas (10) and (14), in order to introduce a "bivalent chain aliphatic group", a "bivalent cyclic aliphatic group" or a "divalent aromatic group" into the R _{2 of the} formula (10) It is preferred to use a corresponding diamine component or diisocyanate component in the R ₂ ' position of the formula (14). That is, by appropriately selecting "aromatic diamine or its corresponding aromatic diisocyanate", "cyclic aliphatic diamine or its corresponding cyclic aliphatic diisocyanate", "chain aliphatic diamine or The chain type aliphatic diisocyanate corresponding thereto can obtain a polyester phthalimide resin which is excellent in heat resistance, flexibility, and low moisture absorption.

The diamine component of R ₂ of the formula (10) and R ₂ ' of the formula (14) or the diisocyanate component corresponding thereto may be the same or different. It is preferably the same if it is a suitable manufacturing method as described later.

The diamine component having R ₂ and R ₂ ' as a basic skeleton or a diisocyanate component corresponding thereto will be described.

"Aromatic diamine or an aromatic diisocyanate corresponding thereto", specific examples of the diamine compound include 2,2'-bis(trifluoromethyl)benzidine and p-phenylenediamine. M-phenylenediamine, 2,4-diaminotoluene, 2,5-diaminotoluene, 2,4-diaminoxylene, 2,4-diaminoduene, 4,4'-diamine Diphenylmethane, 4,4'-methylenebis(2-methylaniline), 4,4'-methylenebis(2-ethylaniline), 4,4'-methylenebis (2 ,6-dimethylaniline), 4,4'-methylenebis(2,6-diethylaniline), 4,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl Ether, 3,3'-diaminodiphenyl ether, 2,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl hydrazine, 3,3'-diaminodiphenyl hydrazine, 4,4'-diaminobenzophenone, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl sulfide Ether, 4,4'-diaminodiphenylpropane, 3,3'-diaminodiphenylpropane, 4,4'-diaminobenzimidamide, p-xylenediamine, m-xylene Diamine, 1,4-naphthalenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, 2,7-naphthalenediamine, benzidine, 3,3'-dihydroxybenzidine, 3, 3'-dimethoxybenzidine, 3 , 3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-diethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4, 4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-diethoxy-4,4'-diaminobiphenyl, o-toluidine, m-toluidine, 1,4-bis(4-aminophenoxy)benzene, 1,3 - bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, double (4 -(3-Aminophenoxy)phenyl)anthracene, bis(4-(4-aminophenoxy)phenyl)anthracene, 2,2-bis(4-(4-aminophenoxy) Phenyl)propane, 2,2-bis(4-(4-amino) Phenoxy)phenyl)hexafluoropropane, 2,2-bis(4-aminophenyl)hexafluoropropane, diamine-linked triphenyl, and the like. In addition, these may be used in combination of two or more types.

Further, examples of the "cycloaliphatic diamine or the corresponding cyclic aliphatic diisocyanate" include a diamine compound, and examples thereof include trans-1,4-diaminocyclohexane and cis-1,4. -diaminocyclohexane, 1,4-diaminocyclohexane (reverse/cis mixture), 1,3-diaminocyclohexane, 4,4'-methylenebis(cyclohexylamine) (anti-body, cis, trans/cis mixture), isophorone diamine, 1,4-cyclohexane bis(methylamine), 2,5-bis(aminomethyl)bicyclo[2.2.1]g Alkane, 2,6-bis(aminomethyl)bicyclo[2.2.1]heptane, 3,8-bis(aminomethyl)tricyclo[5.2.1.0]decane, 1,3-diamine, adamantane , 4,4'-methylenebis(2-methylcyclohexylamine), 4,4'-methylenebis(2-ethylcyclohexylamine), 4,4'-methylenebis (2 , 6-dimethylcyclohexylamine), 4,4'-methylenebis(2,6-diethylcyclohexylamine), 2,2-bis(4-aminocyclohexyl)propane, 2, 2-bis(4-aminocyclohexyl)hexafluoropropane or the like. In addition, these may be used in combination of two or more types.

The "chain aliphatic diamine or the corresponding chain aliphatic diisocyanate" may, for example, be a 1,3-propanediamine or a 1,4-tetramethylenediamine, or a diamine compound. , 5-pentamethylenediamine, 1,6-hexamethylenediamine, 1,7-heptamethylenediamine, 1,8-octamethylenediamine, 1,9-九亚甲Diamine and the like. In addition, these may be used in combination of two or more types.

From the viewpoints of heat resistance, flexibility, and low moisture absorption balance, it is suitable as R ₂ in the formula (10) and a diamine component of R ₂ ' in the formula (14) or a diisocyanate component corresponding thereto. The composition, if the diamine compound is taken as an example, is p-phenylenediamine, 2,4-diaminotoluene, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl Residues derived from ether, 1,5-naphthalenediamine, o-toluidine, diaminotriphenyl, 4,4'-methylenebis(cyclohexylamine), isophoronediamine, and the like. Preferred is 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenyl ether, 1,5-naphthalenediamine, ortho-toluidine, more preferably 4,4'-di Aminodiphenylmethane, 4,4'-diaminodiphenyl ether, o-tolidine. Most preferred are residues derived from 4,4'-diaminodiphenylmethane or o-tolidine.

From the viewpoint of excellent transparency of the polyimide film and heat correction by heat shrinkage, it is preferred that the polyimide of the present invention contains a fluorinated polyimide. When the content of fluorine in the film is in the range of 1 to 40% by mass, the effect of the present invention is large, and is preferable.

<Physical properties of polyimine film> (total light transmittance)

The polyimine film of the present invention is a transparent polyimide film, and the standard of transparency is preferably 80% or more. More than 85% is preferred, and more than 90% is more preferred. The higher the total light transmittance, the higher the transparency, so it is suitable. A numerical value indicating that the total light transmittance is 80% or more represents a suitable range.

The total light transmittance of the polyimide film can be measured for a polyimide film sample which is humidity-conditioned for 24 hours in an air-conditioned room at 23 ° C and 55% R.H. in accordance with JIS K 7375-2008. The measurement was performed using a spectrophotometer U-3300 of Hitachi High Technologies Co., Ltd., and the transmittance in the visible light region (range of 400 to 700 nm) was measured.

In order to make the total light transmittance 80% or more, it can be adjusted by selecting the kind of the above-mentioned polyimine.

(yellow index value (YI value))

The polyimine film of the present invention is a colorless polyimide film having a colorless standard, preferably having a yellow index value (YI value) of 4.0 or less. It is preferably in the range of 0.3 to 2.0, and particularly preferably in the range of 0.3 to 1.6. The smaller the yellow index value (YI value), the less the coloration, so it is suitable. The yellow index value (YI value) is a numerical value of 4.0 or less, and represents a suitable range.

The aforementioned YI value can be adjusted by selecting the type of the above polyimine.

The yellow index value can be obtained from the YI (yellow index: yellowish index) of the film specified in JIS K 7103.

The method for measuring the yellow index value is to first prepare a sample of the film, and use the spectrophotometer U-3300 of Hitachi High Technologies Co., Ltd. and an attached chroma calculation program to obtain the color of the light source specified in JIS Z 8701. The tristimulus values X, Y, and Z, and the yellow index value is obtained according to the definition of the following formula.

Yellow index (YI) = 100 (1.28X-1.06Z) / Y

(solubility)

The polyimine film of the present invention preferably has a solubility (limit of dissolution) of 100 g with respect to 100 g of dichloromethane at 25 ° C. When the solubility is 1 g or more, it is easy to produce by a solution casting method, and the solubility is increased, and the more easily it is produced by a solution casting method, it is suitable. The numerical value of the solubility of 1 g or more is represented by the appropriate range. The solubility of the polyimine contained in the polyimide film at 100 ° C relative to 100 g of dichloromethane The (limit amount of dissolution) is preferably 1 g or more.

(heat shrinkage rate)

The polyimine film of the present invention has a heat shrinkage ratio defined by the following formula in the range of 0.5 to 20.0%.

Heat shrinkage rate (%) = {(Lo-L) / Lo} × 100

(However, Lo represents the length of the sample before the test at 25 ° C, and L represents the length of the sample when the sample is stored at 230 ° C for 10 minutes and then cooled to 25 ° C.).

The heat shrinkage rate can be measured according to ASTM specification D-1204 according to the following procedure.

[1] The length of the test piece was measured before heating.

[2] The test piece was suspended at 230 ° C and under a load with a hot air circulating thermostat for 10 minutes.

[3] After cooling to room temperature, the length of the test piece was measured in the same portion as that previously measured.

[4] The heat shrinkage ratio was calculated in accordance with the calculation formula defined by the above formula of the heat shrinkage ratio (%).

Further, in the case where the polyimide film was in the form of a long roll, the heat shrinkage ratio in the width direction (the conveyance direction and the vertical direction) of the film was measured.

If the heat shrinkage rate is more than 0.5%, the polyimide film is easily thermally corrected to improve planarity. Further, when the heat shrinkage ratio is more than 20.0%, the shrinkage ratio is excessively large, and thus the planarity is liable to be deteriorated.

The heat shrinkage ratio can be adjusted by the selection of the type of the polyimine, the drying temperature in the production process of the polyimide film described later, or the type of solvent used in the preparation of the coating. Further, depending on the case, the heat shrinkage rate must be adjusted by the elongation rate of the polyimide film and the change in the concentration of the residual solvent during stretching.

<Inorganic filler>

An inorganic filler may be mixed in the polyimide film of the present invention.

By setting the mixing ratio of the inorganic filler in the polyimide film to 0.01% by mass or more, the slip property can be improved, and the planarity is not easily deteriorated. In addition, when it is made 2.0% by mass or less, there is an effect of preventing an increase in the haze of the polyimide film.

In the polyimine film, it is difficult to add a large amount of fine particles. However, by using the constitution of the present invention, even when the amount of fine particles added is small (0.01 to 2.0% by mass is added to the polyimide film), The advantage of planar deterioration heat correction.

As the inorganic filler, fine particles of the following inorganic compound are preferably used. Examples of the fine particles of the inorganic compound include cerium oxide, titanium oxide, aluminum oxide, zirconium oxide, calcium carbonate, calcium carbonate, talc, clay, calcined kaolin, calcined calcium citrate, calcium citrate hydrate, and aluminum citrate. Magnesium citrate and calcium phosphate. From the viewpoint of a decrease in turbidity, the fine particles should preferably contain cerium, and particularly preferably cerium oxide.

The average particle diameter of the primary particles of the fine particles is preferably in the range of 5 to 400 nm, more preferably in the range of 10 to 300 nm. These may also contain the Lord If the secondary aggregates having a particle diameter of 0.05 to 0.3 μm are particles having an average particle diameter of 80 to 400 nm, they do not aggregate, and it is also suitable to contain the particles as primary particles.

In the polyimide film, the content of these fine particles is more preferably in the range of 0.01 to 1% by mass, and particularly preferably in the range of 0.05 to 0.5% by mass.

In the case of producing a multilayered polyimide film by a co-casting method, the surface preferably contains the added amount of fine particles.

For the fine particles of cerium oxide, for example, products of Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, and TT600 (all manufactured by Nippon Aerosil Co., Ltd.) are commercially available and can be used.

For the zirconia fine particles, for example, products of Aerosil R976 and R811 (all manufactured by Nippon Aerosil Co., Ltd.) are commercially available and can be used.

Examples of the fine particles of the resin include a polyoxyl resin, a fluororesin, and an acrylic resin. It is preferably a polyoxyxene resin, and it is particularly preferable to have a three-dimensional network structure, for example, products of Tospearl 103 and the same series of 105, 108, 120, 145, 3120 and 240 (above, Toshiba Silicone Co., Ltd.) are sold in the market. And can be used.

Among these, Aerosil 200V and Aerosil R972V are particularly suitable for use because they maintain a low haze film and have a high friction coefficient.

<Other additives> (UV absorber)

From the viewpoint of improving light resistance, the polyimide film of the present invention preferably contains an ultraviolet absorber. The ultraviolet absorber is intended to enhance light resistance by absorbing ultraviolet rays of 400 nm or less, and particularly preferably at a wavelength of 370 nm, preferably in the range of 0.1 to 30%, preferably 1 to 20%, more preferably 2 ~10% range.

The ultraviolet absorber which is suitably used in the present invention is a benzotriazole-based ultraviolet absorber, a benzophenone-based ultraviolet absorber, a triazine-based ultraviolet absorber, particularly preferably a benzotriazole-based ultraviolet absorber and a benzophenone. It is a UV absorber.

For example, 5-chloro-2-(3,5-di-secondbutyl-2-hydroxyphenyl)-2H-benzotriazole, (2-2H-benzotriazol-2-yl)-6 - (linear and side chain dodecyl)-4-methylphenol, 2-hydroxy-4-benzyloxybenzophenone, 2,4-benzyloxybenzophenone, etc., in addition to TINUVIN 109, The TINUVIN class of TINUVIN 171, TINUVIN 234, TINUVIN 326, TINUVIN 327, TINUVIN 328, TINUVIN 928, etc., which are all commercially available from BASF Japan Co., Ltd., are suitable for use. Among them, halogen-free ones are preferred.

Further, a disk-shaped compound such as a compound having a 1,3,5-triazine ring or the like is preferably used as the ultraviolet absorber.

The polyimine film of the present invention preferably contains two or more kinds of ultraviolet absorbers.

In addition, UV absorbers are also suitable for the use of high molecular UV The line absorber is particularly preferably a polymer type ultraviolet absorber described in JP-A-6-148430. Further, the ultraviolet absorber preferably has no halogen group.

The method of adding the ultraviolet absorber may dissolve the ultraviolet absorber in an alcohol such as methanol, ethanol or butanol or an organic solvent such as methylene chloride, methyl acetate, acetone or dipentane or a mixed solvent thereof. , then added to the coating, or can be added directly to the coating composition.

The ultraviolet absorber which is insoluble in an organic solvent like an inorganic powder can be dispersed in an organic solvent and a polyimide film using a dissolver or a sand mixer, and then added to the coating.

The amount of the ultraviolet absorber to be used varies depending on the type of the ultraviolet absorber, the conditions of use, and the like. When the dried film thickness of the polyimide film is 15 to 50 μm, the film is formed with respect to the polyimide film. The range of 0.5 to 10% by mass is preferably, and the range of 0.6 to 4% by mass is more preferable.

(Antioxidants)

Antioxidants are also referred to as deterioration inhibitors. When the electronic device or the like is placed in a state of high humidity and high temperature, the polyimide film may be deteriorated.

The antioxidant has a function of, for example, delaying, preventing the polyimine film from decomposing due to the amount of residual solvent in the polyimide film or the phosphoric acid of the phosphate-based plasticizer, and therefore it is preferably contained in the polybenzazole of the present invention. In the imine film.

This antioxidant is suitable for use with hindered phenolic compounds. For example, 2,6-di-t-butyl-p-cresol, pentaerythritol-indole [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], Ethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di Third butyl-4-hydroxyphenyl)propionate], 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylanilino)-1 , 3,5-triazine, 2,2-thio-divinylbis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl)propionate, N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxy-hydrocinnamylamine ), 1,3,5-trimethyl-2,4,6-parade (3,5-di-t-butyl-4-hydroxybenzyl)benzene, gins-(3,5-di-t-butyl) -4-Hydroxybenzyl)-isocyanurate and the like.

Particularly preferred is 2,6-di-t-butyl-p-cresol, pentaerythritol-indole [3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], three Ethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate]. Further, a hydrazine-based metal deactivator such as N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propanyl] hydrazine or the like may be used in combination. A phosphorus-based processing stabilizer such as 4-di-tert-butylphenyl phosphite.

The amount of these compounds added is preferably in the range of 1 ppm to 1.0%, and more preferably in the range of 10 to 1000 ppm, based on the mass ratio of the polyimide film.

(phase difference control agent)

In order to improve the display quality of the image display device such as a liquid crystal display device, a phase difference control agent may be added to the polyimide film or an alignment film may be formed, and a liquid crystal layer may be provided to protect the film and the liquid crystal layer from the polarizing plate. The phase difference is combined to impart optical compensation to the polyimide film.

The phase difference control agent may, for example, be an aromatic compound having two or more aromatic rings as described in the specification of the European Patent No. 911656A2, and a rod-shaped compound described in JP-A-2006-2025. Further, two or more aromatic compounds may be used in combination. The aromatic ring of the aromatic compound is preferably an aromatic heterocyclic ring containing an aromatic heterocyclic ring in addition to the aromatic hydrocarbon ring. The aromatic heterocyclic ring is generally an unsaturated heterocyclic ring. In particular, it is preferably a 1,3,5-triazine ring described in JP-A-2006-2026.

The amount of the phase difference controlling agent to be added is preferably in the range of 0.5 to 20% by mass, and preferably in the range of 1 to 10% by mass based on 100% by mass of the polyimide film.

(peeling accelerator)

In order to improve the peelability at the time of film production, a peeling accelerator may be added to the polyimide film of the present invention.

Many surfactants have a significant effect on the reduction of the peeling resistance of the polyimide film. Suitable release agents such as phosphate ester surfactants, carboxylic acid or carboxylate surfactants, sulfonic acid A sulfonate-based surfactant or a sulfate-based surfactant is effective. Further, a fluorine-based surfactant which is substituted with a fluorine atom and is bonded to a part of hydrogen atoms of a hydrocarbon chain of the above surfactant is also effective. The release agent is exemplified below.

RZ-1 C ₈ H ₁₇ OP(=O)-(OH) ₂

RZ-2 C ₁₂ H ₂₅ OP(=O)-(OK) ₂

RZ-3 C ₁₂ H ₂₅ OCH ₂ CH ₂ OP(=O)-(OK) ₂

RZ-4 C ₁₅ H ₃₁ (OCH ₂ CH ₂ ) ₅ OP(=O)-(OK) ₂

RZ-5 {C ₁₂ H ₂₅ O(CH ₂ CH ₂ O) ₅ } ₂ -P(=O)-OH

RZ-6 {C ₁₈ H ₃₅ (OCH ₂ CH ₂ ) ₈ O} ₂ -P(=O)-ONH ₄

RZ-7 (tC ₄ H ₉ ) ₃ -C ₆ H ₂ -OCH ₂ CH ₂ OP(=O)-(OK) ₂ RZ -8 (iso-C ₉ H ₁₉ -C ₆ H ₄ -O-(CH ₂ CH ₂ O) ₅ -P(=O)-(OK)(OH)

RZ-9 C ₁₂ H ₂₅ SO ₃ Na

RZ-10 C ₁₂ H ₂₅ OSO ₃ Na

RZ-11 C ₁₇ H ₃₃ COOH

RZ-12 C ₁₇ H ₃₃ COOH. N(CH ₂ CH ₂ OH) ₃

RZ-13 iso-C ₈ H ₁₇ -C ₆ H ₄ -O-(CH ₂ CH ₂ O) ₃ -(CH ₂ ) ₂ SO ₃ Na

RZ-14 (iso-C ₉ H ₁₉ ) ₂ -C ₆ H ₃ -O-(CH ₂ CH ₂ O) ₃ -(CH ₂ ) ₄ SO ₃ Na

RZ-15 sodium triisopropyl naphthalene sulfonate

RZ-16 tri-tertiary butyl naphthalene sulfonate

RZ-17 C ₁₇ H ₃₃ CON(CH ₃ )CH ₂ CH ₂ SO ₃ Na

RZ-18 C ₁₂ H ₂₅ -C ₆ H ₄ SO ₃ . NH ₄

The amount of the release accelerator added is preferably 0.05 to 5% by mass, more preferably 0.1 to 2% by mass, and most preferably 0.1 to 0.5% by mass, based on the polyimine.

<Method for Producing Polyimine Film>

Specific examples of the method for producing the above polyimide film will be described below.

The method for producing a polyimide film preferably has a step of dissolving the polyacrylic acid or polyimine in a solvent to prepare a coating material (a coating preparation step), and casting the coating material on a support to form a cast film. a step (casting step), a step of evaporating the solvent cast film on the support (solvent evaporation step), a step of peeling the cast film from the support (peeling step), drying the obtained cast film, and obtaining a film Step (first dry a drying step), a step of stretching the dried film (extension step), a step of drying the stretched film (second drying step), and a step of winding the obtained polyimide film (winding step), Even if necessary, there may be a step of heat-treating the film to imidize the oxime (heating step) and the like.

In the present invention, the following procedure is suitable because it is easy to increase the heat shrinkage rate.

That is, it is preferable to prepare a film containing a polyimide film having the following steps: dissolving polylysine or polyimine in a solvent having a boiling point of 40 to 80 ° C to prepare a coating adjustment step of the coating. a casting step of casting the coating onto the support to form a cast film; a solvent evaporation step of evaporating the solvent from the casting film; a stripping step of peeling the cast film for evaporating the solvent from the support; and casting the stripping The film is dried at 10 to 200 ° C to obtain a drying step of the film; and an extending step of extending the dried film.

The following is specifically described for each step.

(paint preparation step)

In the method for producing a polyimide film of the present invention, it is preferred to prepare a film by dissolving at least a polyimine and a hydrogen bond compound in a solvent having a low boiling point to prepare a coating material, and using the coating material to form a film by a solution casting film forming method.

The low boiling point solvent uses a low boiling point solvent having a boiling point of 80 ° C or less as a main solvent, and is suitable because the film can be lowered in the production process temperature (particularly, drying temperature) and the heat shrinkage ratio can be adjusted. Here "use In the case of a mixed solvent, the solvent is used in an amount of 55 mass% or more, preferably 70 mass% or more, preferably 80 mass% or more, and particularly preferably 90 mass% or more. Of course, if it is used alone, it is 100% by mass.

The low-boiling point solvent may be obtained by simultaneously dissolving polyimine and other additives. For example, a chlorine-based solvent may, for example, be a dichloromethane; and a non-chlorinated solvent may, for example, methyl acetate, ethyl acetate, amyl acetate or acetone. Methyl ethyl ketone, tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, cyclohexanone, ethyl formate, 2,2,2-trifluoroethanol, 2,2,3,3 - hexafluoro-1-propanol, 1,3-difluoro-2-propanol, 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol, 1,1, 1,3,3,3-hexafluoro-2-propanol, 2,2,3,3,3-pentafluoro-1-propanol, nitroethane, methanol, ethanol, n-propanol, isopropanol , n-butanol, second butanol, third butanol, and the like.

Wherein, the low boiling point solvent having a boiling point of 80 ° C or less is preferably selected from the group consisting of dichloromethane (40 ° C), ethyl acetate (77 ° C), methyl ethyl ketone (79 ° C), and tetrahydrofuran (66 ° C). At least one of acetone (56.5 ° C) and 1,3-dioxolane (75 ° C) is used as a main solvent (boiling points in parentheses).

In addition, when the solvent is mixed, the solvent contained in the present invention can be used in a range that does not inhibit the effects of the present invention, and the solvent other than the above can be used as long as it can dissolve the polyimine and the organic compound having a carbonyl group. For example, N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylformamide, N,N- can be used. Diethylformamide, N-methyl caprolactam, hexamethylphosphoniumamine, tetramethylene Bismuth, dimethyl hydrazine, m-cresol, phenol, p-chlorophenol, 2-chloro-4-hydroxytoluene, diglyme, triglyme, tetraglyme, dioxane Γ-butyrolactone, dioxolane, cyclopentanone, ε-caprolactam, chloroform, or the like may be used in combination of two or more. Further, in the case where the polyimine and the organic compound having a carbonyl group which are related to the present invention are not precipitated, these solvents may be mixed with hexane, heptane, benzene, toluene, xylene, chlorobenzene, o-dichlorobenzene or the like. Use poor solvent together.

Further, an alcohol solvent can also be used. The alcohol solvent is preferably selected from the group consisting of methanol, ethanol, and butanol from the viewpoint of improving the peelability and casting at a high speed. It is especially preferred to use methanol or ethanol. When the ratio of the alcohol in the coating material becomes high, the tape is colloidal and is easily peeled off from the metal support.

For the dissolution of polyimine and other additives, a method carried out under normal pressure; a method carried out below the boiling point of the main solvent; a method of pressurizing at a boiling point or higher of the main solvent; in accordance with Japanese Patent Laid-Open No. 9-95544 A method of performing a cooling and dissolving method described in Japanese Laid-Open Patent Publication No. Hei 9-95538, and a method of performing under high pressure as described in JP-A-11-21379 Dissolution method.

The prepared paint can be filtered by a liquid feed pump or the like to be guided to a filter. For example, in the case where the main solvent of the coating material is methylene chloride, the coating material can be removed by filtering the coating material at a temperature of +5 ° C or higher at a boiling point of 1 atm. A suitable temperature range is 45 to 120 ° C, preferably 45 to 70 ° C, and more preferably 45 to 55 ° C.

In addition, in most cases, in the main paint, the recycled material will account for 10 to 50% by mass. The recycled material refers to a portion which is reused as a raw material for some reasons, and for example, a film obtained by pulverizing a polyimide film into a fine powder, and a side portion of the film which is produced when the polyimide film is formed into a film. A cut-off object, or a polyimide film material which exceeds a predetermined value of a film due to abrasion or the like.

Further, as the raw material of the resin used for the preparation of the paint, it is also suitable to use an object obtained by pelletizing a polyimide or other compound in advance.

(cast film forming step)

The prepared paint is conveyed to the die through a liquid-feeding pump (for example, a pressurized metering gear pump), and cast on an endless support of an infinitely transported end, such as a metal support such as a stainless steel belt or a rotating metal drum. The position is cast from the die.

The surface of the cast metal support is preferably mirror-finished, and the support is suitable for a metal support such as a stainless steel strip or a cast and a plated surface. The width of the casting can be set in the range of 1 to 4 m, and should be set in the range of 1.5 to 3 m, more preferably in the range of 2 to 2.8 m. Further, the support may not be made of metal, and for example, a polyethylene terephthalate (PET) film, a polyethylene naphthalate (PEN) film, or a polybutylene terephthalate (PBT) film may be used. , nylon 6 film, nylon 6,6 film, polypropylene film, polytetrafluoroethylene and other belts. In the case where a polyimide film is used as the flexible substrate, a metal support of the polyimine may be cast or the above The film is wound together with a polyimide film.

The moving speed of the metal support is not particularly limited, but is usually 5 m/min or more, preferably 10 to 180 m/min, and particularly preferably 80 to 150 m/min. The higher the moving speed of the metal support, the more likely the entrained gas is generated, and the more uneven the film thickness is caused by the disturbance.

The moving speed of the metal support is the moving speed of the outer surface of the metal support.

Regarding the surface temperature of the metal support, the higher the temperature, the faster the drying speed of the cast film is, so it is suitable. However, if it is too high, the cast film may be foamed or the planarity may be deteriorated. Therefore, it is preferable to The solvent to be used has a boiling point of from -50 to -10 °C.

The die has a shape which is tapered toward the discharge port in a cross section perpendicular to the width direction. Specifically, the die has a sloped surface in the lower moving direction and on the downstream side and the upstream side, and a discharge port is formed in a slit shape between the inclined surfaces. The die is preferably a die made of metal, and specific examples thereof include stainless steel, titanium, and the like. In the present invention, when a film having a different thickness is produced, it is not necessary to change the die having a different slit gap.

It is preferable to use a slit shape in which the metal nozzle portion of the die can be adjusted, and it is easy to make the pressurizing die having a uniform film thickness. The press die has a hanger die or a T die, and any of them is suitable for use. Even when a film having a different thickness is continuously produced, the discharge amount of the die is maintained at a constant value. Therefore, when a press die is used, conditions such as extrusion pressure and shear rate are roughly Maintain a certain value. In addition, in order to increase the film forming speed, two or more press dies may be placed on the metal support, and The amount of the coating is divided and laminated.

(solvent evaporation step)

The solvent evaporation step is a preliminary drying step performed on a metal support by heating the cast film on a metal support to evaporate the solvent.

In order to evaporate a solvent, for example, a method of blowing heated air from the side of the casting film and the back side of the metal support by a dryer, a method of transferring heat by heating the liquid from the back surface of the metal support, and radiant heat from the front and back sides may be mentioned. Heat transfer method, etc. A method of appropriately selecting such combinations is also suitable. The surface temperature of the metal support may be the same as the whole or may vary depending on the position. The temperature of the heated air should be in the range of 10 to 220 °C.

The temperature (drying temperature) of the heating air is preferably 200 ° C or less, more preferably 140 ° C or less, and still more preferably 120 ° C or less.

In the solvent evaporation step, from the viewpoint of the peelability of the cast film and the conveyability after peeling, the cast film is preferably dried until the amount of the residual solvent is in the range of 10 to 150% by mass.

In the present invention, the amount of residual solvent can be expressed by the following formula.

Residual solvent amount (% by mass) = {(M - N) / N} × 100

Here, M is the mass of the cast film (film) at a predetermined time point, and N is the mass of the film of mass M at 200 ° C for 3 hours. Particularly, in the solvent evaporation step, when the amount of residual solvent reached is calculated, M is the mass of the cast film immediately before the peeling step.

(peeling step)

On the metal support, the cast film obtained by evaporating the solvent was peeled off at the peeling position.

When the metal support is peeled off from the cast film, the peeling tension is usually in the range of 60 to 400 N/m, and wrinkles are likely to occur at the time of peeling, and it is preferable to peel off at a tension of 190 N/m or less.

In the present invention, the temperature at the peeling position on the metal support is preferably in the range of -50 to 60 ° C, preferably in the range of 10 to 40 ° C, and in the range of 15 to 40 ° C. optimal.

The cast film after peeling (also referred to as a cast film after peeling) can be directly transported to the stretching step, or can be transported to the first drying step to achieve the desired amount of residual solvent, and then transported to the stretching step. In the present invention, from the viewpoint of safely transporting in the stretching step, after the peeling step, the film is preferably transported to the first drying step and the stretching step in order.

(first drying step)

The first drying step is a drying step of heating the film to further evaporate the solvent. The drying means is not particularly limited, and for example, hot air, infrared rays, heating rolls, microwaves, or the like can be used. From the standpoint of simplicity, it is preferable to carry the film by means of a staggered roller and to dry it by hot air or the like. The drying temperature is preferably in the range of 10 to 200 ° C in consideration of the amount of residual solvent and the expansion ratio during transportation.

From controlling the heat shrinkage rate of the polyimide film to the range of the present invention, the polymer chain of the polyimide may not become excessively rigid. It should be noted that the drying temperature is preferably 200 ° C or less. The lower limit is 10° C. or more, and from the viewpoint of production efficiency such as heat shrinkage rate and drying time, it is preferably 100° C. or higher, and particularly preferably 120° C. or higher.

The heat shrinkage rate of the film can be increased by setting the drying temperature to a low temperature of 200 ° C or lower.

(extension step)

The film thickness, flatness, alignment, and the like of the film can be controlled by stretching the film peeled off from the metal support.

In the method for producing a film of the present invention, it is preferred to extend in the longitudinal direction or the width direction.

The stretching operation can be implemented in multiple stages. Further, in the case of biaxial stretching, biaxial stretching may be simultaneously performed or may be carried out in stages. In this case, the stage may be, for example, a different extension of the extension direction, or may be divided into multiple stages in the same direction, and the extension of the different directions may be added to any stage.

That is, for example, it may be an extension step as follows:

‧ Extend in the length direction → Extend in the width direction → Extend in the length direction → Extend in the length direction

‧ Extend in the width direction → Extend in the width direction → Extend in the length direction → Extend in the length direction

In addition, the simultaneous biaxial extension also includes a case where the tension is extended in one direction and the tension is relaxed and contracted in the other direction. At the same time, the appropriate extension ratio of the biaxial extension can be set to ×1.01 times in the width direction and the length direction. × 1.5 times the range. Here, the stretching ratio (the length of the stretched width or length of the film) / (the length of the film before the extension or the length of the length).

The amount of the residual solvent at the start of stretching is preferably in the range of 0.1 to 200% by mass.

When the amount of the residual solvent is 0.1% by mass or more, the effect of improving the planarity can be obtained by stretching, and if it is 200% or less, the elongation is easy.

In order to increase the heat shrinkage ratio of the polyimide film of the present invention, the amount of the residual solvent in the film is preferably 0.1 to 2.0% by mass, and preferably 0.1 to 1.0% by mass, at the start of stretching.

In the method for producing a polyimide film of the present invention, it is possible to extend in the longitudinal direction or the width direction so that the film thickness after stretching is in a desired range, and preferably extends in the width direction. The glass transition temperature (Tg) relative to the polyimide film is preferably extended in a temperature range of (Tg - 200 ° C) to (Tg + 100 ° C). If the stretching is performed in the above temperature range, the elongation stress can be lowered, and thus the haze becomes low. In addition, it is possible to obtain a polyimide film which is excellent in planarity and which is excellent in the coloring resistance of the polyimide film itself. The extension temperature is preferably in the range of (Tg - 150 ° C) to (Tg + 50 ° C).

In the method for producing a polyimide film according to the present invention, the film which is peeled off from the support and has self-supporting property can be extended in the longitudinal direction by controlling the moving speed by the stretching roller.

Extending in the width direction, it is suitable to use, for example, all the drying processes or a part of the processing edge disclosed in Japanese Laid-Open Patent Publication No. 62-46625 A method of using a jig or a needle to maintain the width of both ends of the film in the width direction while drying it (referred to as a tenter type) is particularly suitable as a tenter type using a jig.

The film extending in the longitudinal direction or the unstretched film is preferably held at both ends in the width direction by a jig, and is introduced into the tenter in this state, and moves together with the tenter jig while extending in the width direction.

When extending in the width direction, it is preferable to extend in the film width direction at an elongation speed in the range of 50 to 1000%/min from the viewpoint of improving the planarity of the film.

When the stretching speed is 50%/min or more, the planarity is improved, and the film can be processed at a high speed. Therefore, it is suitable from the viewpoint of production suitability, and if it is within 1000%/min, the film can be broken. It is processed and is suitable.

The preferred extension speed is in the range of 100 to 500%/min. The extension speed is defined in accordance with the following formula.

Extension speed (%/min) = [(d ₁ /d ₂ )-1]×100(%)/t

(In the above formula, d ₁ is the width dimension of the extending resin film in the extending direction, d ₂ is the width dimension of the extending direction of the resin film before stretching, and t is the time (min) required for stretching)

In order to increase the heat shrinkage rate of the polyimide film of the present invention, the stretching speed is 200 to 500%/min, more preferably 300 to 500%/min.

In the stretching step, the holding is usually carried out after the stretching. That is, in this step, it is preferable to sequentially perform an extension phase for extending the film, a holding phase for holding the film in an extended state, and extending the film. The easing phase of the direction easing. In the holding phase, the extension of the extension ratio achieved by the extension phase is maintained at the extension temperature in the extension phase. In the mitigation phase, after the extension in the extension phase is maintained in the retention phase, the elongation is relaxed by releasing the tension required for the extension. The relaxation phase may be carried out as long as the elongation is extended below the temperature.

(2nd drying step)

Next, the stretched film is heated and allowed to dry. In the case where the film is heated by hot air or the like, it is also suitable to use a nozzle which can vent the hot air (air containing solvent or humid air) after use to prevent hot air from being mixed in after use. The hot air temperature is preferably in the range of 40 to 350 °C. Further, the drying time is preferably from about 5 seconds to 30 minutes, and preferably from 10 seconds to 15 minutes.

Further, the heating and drying means is not limited to hot air, and for example, infrared rays, heating rolls, microwaves, or the like can be used. From the standpoint of simplicity, it is preferable to carry the film by a roll arranged in a staggered manner while drying with hot air or the like. From the viewpoint that the heat shrinkage tends to become remarkable, the drying temperature is preferably in the range of 40 to 150 °C. 40~120 °C is preferred.

In the second drying step, the film is preferably dried until the amount of residual solvent is 0.5% by mass or less.

(winding step)

The winding step is a step of winding the obtained polyimide film and cooling it to room temperature. The winding machine is a general-purpose machine, and can be used by way of example. Winding is performed by a winding method such as a constant tension method, a fixed torque method, a taper tension method, or a stylized tension control method in which internal stress is constant.

The thickness of the polyimide film is not particularly limited, and is preferably in the range of, for example, 1 to 200 μm, particularly 1 to 100 μm.

In the winding step, at the time of extension conveyance, both ends of the polyimide film sandwiched by the tenter jig or the like may be cut and processed. The end of the cut polyimine film should be cut into a range of 1 to 30 mm wide, and then dissolved in a solvent to be reused as a recycled material.

Among the formed polyimide films, the ratio of the portion to be reused as the recycled material is preferably 10 to 90% by mass, preferably 20 to 80% by mass, and more preferably 30 to 70% by mass.

According to the amount of the recycled material on the way of the film forming step or the final recovery, the amount of the added material may be changed, and the mixing ratio of the recycled material to the total solid content in the coating is usually about 10 to 50% by mass, preferably 15 to 40. Within the range of about % mass. From the perspective of production stability, the mixing rate of recycled materials should be as large as possible.

The above steps of the solvent evaporation step to the winding step may be carried out in an air gas atmosphere or in an inert gas atmosphere such as nitrogen. In addition, each step, particularly the drying step or the stretching step, is carried out in consideration of the explosive limit concentration of the solvent in the gaseous environment.

(heating step)

After the above-mentioned winding step, in order to carry out the oxime imidization between the polymer chain and the polymer chain molecules to improve the mechanical properties, it is also possible to perform the above-mentioned A heating step of further heat treatment of the dried polyimide film in the second drying step.

Further, the second drying step may also serve as a heating step.

The heating means can be carried out using well-known means such as hot air, electric heater, microwave, or the like. The above-mentioned infrared heater can be used for the electric heater.

In the heat treatment conditions, the heating temperature is preferably 200 ° C or lower, preferably 150 ° C or lower, and more preferably 140 ° C or lower.

By setting the drying temperature to a low temperature, the heat shrinkage rate of the polyimide film can be increased.

In the heating step, if the polyimide film is heated abruptly, a problem such as an increase in surface defects occurs, and therefore, the heating method should be appropriately selected. In addition, the heating step is preferably carried out in a low oxygen atmosphere.

From the viewpoint of heat shrinkage of the film, the heating temperature is preferably 150 ° C or less in the second drying step and the heating step. It is preferably 120 ° C or less.

Further, after the winding step, the step of cutting the end portion in the width direction of the polyimide film may be further performed before or after the heating step; or the step of removing the static electricity when the polyimide film is charged.

The polyimine film of the present invention is a polyimide film having a large heat shrinkage rate, and thus it is easy to correct planarity by post-heat treatment. In the case of post-heating, the temperature can be set in the range of 100 ° C to 200 ° C.

<Shape of polyimine film>

The polyimine film of the present invention is preferably elongated, and specifically, preferably has a length in the range of about 100 to 10,000 m and is wound into a roll. Further, the width of the polyimide film of the present invention is preferably 1 m or more, more preferably 1.4 m or more, and particularly preferably 1.4 to 4 m.

<Use>

The polyimine film of the present invention can be corrected for planar heating which deteriorates when laminated with an electronic device. The electronic device to be applied is not particularly limited, and examples thereof include an organic electroluminescence (EL) device, a liquid crystal display device (LCD), an organic photoelectric conversion device, a printed substrate, a thin film transistor, a touch panel, a polarizing plate, and a phase difference. Film and the like. From the viewpoint of more effectively obtaining the effects of the present invention, it is suitably used for a flexible printed circuit board, an LED lighting device, and a front member for a flexible display.

[Examples]

The invention is specifically illustrated by the following examples, but the invention is not limited thereto. In addition, the expression "part" or "%" is used in the examples, and unless otherwise specified, it means "parts by mass" or "% by mass".

[Example 1]

The structures of the compounds used in the examples are listed below.

Further, the source of the commercially available product of the above compound is as follows.

Anhydride 1: Daikin Industries Co., Ltd.

Anhydride 2: Manac Corporation

Anhydride 3: DAICEL Co., Ltd.

Anhydride 5: Mitsubishi Chemical Corporation

Diamine 1: Daikin Industrial Co., Ltd.

Diamine 2: Mitsui Chemical Fine Co., Ltd.

Diamine 4: Mitsui Chemicals Fine Co., Ltd.

<Production of Polyimine Film 101> (Modulation of Polyimine Solution A)

2,2-bis(3,4-dicarboxyphenyl)-1,1,1 in a 4-neck flask equipped with a dry nitrogen gas introduction tube, a condenser tube, a Dean-Stark condenser filled with toluene, and a stirrer. 3,3,3-hexafluoropropane dianhydride (anhydride 1: manufactured by Daikin Industries Co., Ltd.) 25.59 g (57.6 mmol) was added to N,N-dimethylacetamide (134 g) under a nitrogen stream at room temperature Stir under.

14.2 g (60 mmol) of 4,4'-diamino-2,2'-bis(trifluoromethyl)biphenyl (diamine 1: Daikin Industries Co., Ltd.) was added thereto, and the mixture was heated and stirred at 80 ° C. 6 hours. Then, the external temperature was heated to 190 ° C, and the water produced by the imidization of hydrazine was azeotropically distilled off with toluene. After heating for 6 hours, refluxing and stirring were continued, and no water was observed. The toluene was distilled off and heated for 7 hours, and after further distilling off the toluene, methanol was added thereto to reprecipitate, and the solid component was dried, and then a 8% by mass solution of methylene chloride was prepared to prepare a polyglycerin. Polyamidiamine solution A of amine resin A.

(modulation of paint)

A main paint of the following composition was prepared. First, methylene chloride (boiling point 40 ° C) was added to a pressure dissolution tank. The polyimine solution A prepared in the above manner and the remaining components were added to the pressure-dissolving tank filled with the solvent under stirring. This was heated, completely dissolved by stirring, and filtered using Angstrom filter paper No. 244 manufactured by Angki Paper Co., Ltd. to prepare a main paint.

(composition of the main paint)

(casting step)

Next, the coating was uniformly cast on the stainless steel belt support at a temperature of 30 ° C and a width of 1500 mm using an endless belt casting apparatus. The temperature of the stainless steel belt is controlled at 30 °C.

(peeling step)

The solvent in the cast film formed by casting on the stainless steel belt support was evaporated until the residual solvent amount was 75%, and then peeled off from the stainless steel belt support at a peeling tension of 180 N/m.

(first drying step)

The peeled cast film was dried at a first drying temperature of 200 ° C in the first drying step, and the amount of residual solvent at the start of stretching was set to a desired value to obtain a film.

(extension step)

Next, the dried film was heated at 120 ° C, and it was extended by 1.50 times in the width direction at an elongation speed of 1%/sec using a jig tenter. Extension start The amount of residual solvent at the time was 10% by mass.

(2nd drying step)

The handling tension was set to 100 N/m, the drying time was set to 15 minutes, and the stretched film was dried at a second drying temperature of 120 ° C until the residual solvent amount was less than 0.5% by mass to obtain a polyimine having a dry film thickness of 62 μm. film. The obtained polyimide film was entangled to obtain a polyimide film 101.

<Production of Polyimine Films 102 to 113>

In the preparation of the above polyimide film 101, the type of the acid anhydride and the diamine to be used, the type of the solvent, the drying temperature, the elongation rate, and the amount of the residual solvent during the stretching are changed as shown in Table 1, except that Further, similarly to the polyimide film 101, polyimine films 102 to 113 were produced. Further, in the production of the polyimide film 102 to 113, the same amount of moles as the polyimine film 101 was used for the acid anhydride and the diamine.

Each of the above polyimine films was formed into a shape of an elongated film having a width of 1900 mm and a length of 8000 m.

<Production of Rollers 101 to 113>

The wound roll bodies of the above polyimide film 101 to 113 (width: 1900 mm, length: 8000 m) were produced in accordance with the following winding conditions, and were designated as roll bodies 101 to 113.

(winding condition)

Contact roller: diameter 120mm, length 2600mm

Contact roller material: NBR rubber (made by Minghe Rubber Industry Co., Ltd.) WHITE‧ELECON

Hardness 35 degrees, thickness 10mm, CFRP (Carbon Fiber Reinforced Plastics) core

Contact roller pressing: 50N/m

Winding tension: initial tension 250N/m taper 90% corner 25%

Winding speed: 100m/min

Winding shaft diameter: 15.24cm

Winding shaft material: FRP (Fiber Reinforced Plastics)

<Measurement of physical property value of polyimine film>

The total light transmittance, YI value, solubility, and heat shrinkage ratio of the polyimide films 101 to 113 obtained as described above were measured.

Further, the flatness and haze after heat correction were evaluated for the roller bodies 101 to 113.

(total light transmittance)

The total light transmittance of each polyimide film is a sample which is conditioned for 24 hours in an air-conditioned room at 23 ° C and 55% RH. According to JIS K 7375, a spectrophotometer of Hitachi High Technologies Co., Ltd. is used. U-3300, the transmittance in the visible light region (range of 400 to 700 nm) was measured, and the average value of 10 measurements was determined and evaluated according to the following evaluation criteria.

◎: 88% or more

○: 80% or more, less than 88%

×: less than 80%

(yellow index value (YI value))

According to JIS K 7373-2006, one sheet of each polyimide film sample was measured using a spectrophotometer U-3300 of Hitachi High Technologies Co., Ltd. and an attached chroma calculation program. The average of 10 measurements was obtained and evaluated according to the following evaluation criteria.

◎: 0.3 or more, less than 2.0

○: 2.0 or more, 4.0 or less

×: more than 4.0

(solubility)

Each polyimine film was dissolved in 100 g of dichloromethane at 25 ° C, and the upper limit of the solubility was measured. Evaluate according to the following evaluation criteria.

○: solubility is 1 g or more

×: solubility is less than 1g

(heat shrinkage rate)

The heat shrinkage rate can be measured according to ASTM specification D-1204 according to the following procedure.

[1] The length of the test piece before heating was measured at 25 °C.

[2] The test piece was suspended in a hot air circulating thermostat at 230 ° C for 10 minutes under load.

[3] After cooling to room temperature, the length of the test piece was measured in the same portion as that previously measured.

[4] The heat shrinkage rate was calculated according to the calculation formula defined by the following formula of the heat shrinkage rate (%).

The heat shrinkage rate defined by the following formula was measured.

Heat shrinkage rate (%) = {(Lo-L) / Lo} × 100

(However, Lo represents the length of the sample before the test at 25 ° C, and L represents the length of the sample when the sample is stored at 230 ° C for 10 minutes and then cooled to 25 ° C.).

Further, the heat shrinkage ratio is a heat shrinkage ratio in the width direction (the conveyance direction and the vertical direction) of the film of the roll body.

<Evaluation of the roll body> (planarity after heat correction)

Each of the rolls was packed in an aluminum vapor-deposited sheet (having a moisture permeability of 1 g/m ² for 24 hours), and then stored in a warehouse maintained at 23 ° C for 3 months.

The preserved polyimide film was unwound and handled while being heat-treated in a drying oven at 230 ° C for 1 minute.

The number of convex transfer per 1 m ² on the film of 1000 m in the middle of the film after heat treatment was evaluated.

◎: less than 2

○: Less than 2~5

×; 5 or more

[wavy defect] Concave height difference

◎: less than 0.5mm

○: Less than 0.5~1.0

×: 1mm or more

The evaluation results of the composition, production conditions, total light transmittance, YI value, and heat shrinkage ratio of each polyimide film are shown in Table 1.

Further, the results of the planarity after heat correction of each of the rolls were disclosed in Table 1.

As shown in Table 1, it is understood that a polyimide film having a large heat shrinkage ratio and being colorless and transparent can be obtained by the polyimide film of the present invention.

Further, as shown in Table 1, it was found that the roll body produced by using the polyimide film of the present invention has good planarity after heat treatment.

[Example 2]

In the polyimine film 101 of the first embodiment, the content of the inorganic filler (matte agent) in the film is changed to 2.0% by mass, and the polyimine films 101 to 113 are the same, and Polyimine films 201 to 213 were produced.

With respect to the polyimide films 201 to 213, the total light transmittance, the YI value, and the heat shrinkage ratio were measured in the same manner as in Example 1. Table 2 shows the results of evaluation of the composition and production conditions of each polyimide film and the total light transmittance, YI value, and heat shrinkage ratio.

Further, the roll bodies 201 to 213 similar to those of the roll bodies 101 to 113 of the first embodiment were produced using the polyimide films 201 to 213. The flatness and haze of each of the rolls after heat correction were measured in the same manner as in Example 1. The results of the planarity of each roll after heat correction are shown in Table 2.

As shown in Table 2, it was found that the roll body produced by using the polyimide film of the present invention had a good flatness after heat treatment even if the amount of the inorganic filler added was changed.

[Industrial Availability]

The polyimine film of the present invention is excellent in planarity and excellent in coloring and transparency without being excellent in flatness and heat resistance when the film is deteriorated in the form of a roll, and is suitable for use as a flexible printed substrate. LED lighting devices and front members for flexible displays.

Claims (5)

A polyimine film comprising 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl as a diamine and 2,2-bis(3,4-di) a phthalocyanine hexafluoropropane dianhydride or a biphenyltetracarboxylic dianhydride polymerized as an acid dianhydride to synthesize a poly phthalic acid or a polyimide phthalimide as a main component. It is characterized in that the total light transmittance is 80% or more, and the yellow index value (YI value) is 4.0 or less, and 1 g or more is dissolved with respect to 100 g of dichloromethane at 25 ° C, and heat defined by the following formula The shrinkage rate is in the range of 0.5 to 20.0%, and the heat shrinkage rate (%) = {(Lo-L) / Lo} × 100 (but Lo represents the length of the sample before the test at 25 ° C, L This indicates the length of the sample when the sample was stored at 230 ° C for 10 minutes and then cooled to 25 ° C. The polyimine film according to claim 1, wherein the inorganic filler is contained in the range of 0.01 to 2.0% by mass. A polyimine film according to claim 1 or 2, which comprises a fluorinated polyimine as the aforementioned polyimine. A method for producing a polyimide film, which is a polyimine film of a polyimide film according to any one of claims 1 to 3. The production method is characterized in that the polyimine film contained in the polyimide film uses 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl as a diamine, and is used. Polyacrylic acid or polyimine synthesized by polymerization of 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride or biphenyltetracarboxylic dianhydride as acid dianhydride, using the aforementioned A synthetic polyaminic acid or polyimine is used to make a polyimide film. A method for producing a polyimine film, which is a method for producing a polyimide film of a polyimide film according to any one of claims 1 to 3, which is characterized in that: , 2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl as diamine, using 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride or biphenyl The polyamic acid or polyimine synthesized by the polymerization of the tetracarboxylic dianhydride as the acid dianhydride is dissolved in a solvent having a boiling point of 40 to 80 ° C to prepare a coating preparation step of the coating; the coating is cast in the coating a casting step of forming a cast film; a solvent evaporation step of evaporating a solvent from the cast film; a stripping step of peeling the cast film for evaporating the solvent from the support; and the peeling cast film at 10 to 200 ° C A drying step of drying to obtain a film; and an extending step of extending the dried film.