WO2023149435A1

WO2023149435A1 - Resin composition, molded object, and film

Info

Publication number: WO2023149435A1
Application number: PCT/JP2023/003097
Authority: WO
Inventors: 文康石黒
Original assignee: 株式会社カネカ
Priority date: 2022-02-03
Filing date: 2023-01-31
Publication date: 2023-08-10

Abstract

A resin composition comprising a polyimide and an acrylic resin, wherein the polyimide comprises an alicyclic tetracarboxylic dianhydride as at least some of a tetracarboxylic dianhydride component and a fluoroalkyl-substituted benzidine as a diamine component. The amount of the alicyclic tetracarboxylic dianhydride may be 10-100 mol% with respect to the whole tetracarboxylic dianhydride component of the polyimide. The degree of acetyl substitution of an acetylcellulose-based resin may be 2.4 or greater. The resin composition may comprise the polyimide and the acetylcellulose-based resin in a weight ratio in the range of 98:2 to 2:98.

Description

Resin composition, molding and film

The present invention relates to resin compositions and molded articles such as films.

Because transparent polyimide has transparency and high heat resistance, it is used for display substrates and cover films. A normal polyimide film is obtained by coating a polyamic acid solution, which is a polyimide precursor, on a support in the form of a film, and subjecting it to a high temperature treatment to remove the solvent and perform thermal imidization at the same time. However, the heating temperature for thermal imidization is high (for example, 300 ° C. or higher), and coloring (increase in yellowness) due to heating is likely to occur, making it difficult to apply to applications requiring high transparency such as cover films for displays. Have difficulty.

As a method for producing a highly transparent polyimide film, a method using a polyimide resin that is soluble in organic solvents and does not require imidization at high temperatures after film formation has been proposed. For example, Patent Document 1 discloses that polyimides containing bis-trimellitic anhydride esters as tetracarboxylic dianhydride components are soluble in low-boiling solvents such as methylene chloride and have excellent transparency and mechanical strength. is described.

WO2020/004236

Although transparent polyimide has better heat resistance than general-purpose transparent resins, higher transparency is required when used for display cover films. Although the transparent polyimide of Patent Document 1 is not colored in the imidization process, it has a higher degree of yellowness than general-purpose resins. Moreover, the transparent polyimide of Patent Document 1 has a problem that it turns yellow when exposed to ultraviolet rays, and the degree of yellowness increases. In view of such problems, an object of the present invention is to provide a transparent film having high heat resistance and excellent transparency and light resistance, and a resin composition used for producing the same.

The present inventors have found that polyimides having a specific chemical structure and acetylcellulose-based resins show compatibility, and by using a resin composition in which these are mixed, a highly transparent film can be produced without impairing the excellent heat resistance of polyimides. We have found that it is possible, and have solved the above problems.

One aspect of the present invention relates to a film and a resin composition containing a polyimide resin and an acetylcellulose resin. The resin composition may contain a polyimide resin and an acetylcellulose resin in a weight ratio ranging from 98:2 to 2:98.

The polyimide contains an alicyclic tetracarboxylic dianhydride as the tetracarboxylic dianhydride component, an alicyclic tetracarboxylic dianhydride as the tetracarboxylic dianhydride component, and a fluoroalkyl-substituted benzidine as the diamine component. including.

The amount of the alicyclic tetracarboxylic dianhydride relative to the total amount of the tetracarboxylic dianhydride component of the polyimide is preferably 10 to 100 mol%. The alicyclic tetracarboxylic dianhydrides include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,4 ,5-cyclohexanetetracarboxylic dianhydride and 1,1′-bicyclohexane-3,3′,4,4′tetracarboxylic acid-3,4:3′,4′-dianhydride are preferred.

The amount of the fluoroalkyl-substituted benzidine with respect to the total amount of the diamine component of the polyimide is preferably 50 mol% or more. As the fluoroalkyl-substituted benzidine, perfluoroalkyl-substituted benzidine such as 2,2'-bis(trifluoromethyl)benzidine is preferred.

The degree of acetyl substitution of the acetylcellulose-based resin may be 2.4 or more.

The film of one embodiment of the present invention has a thickness of 5 μm or more and 300 μm or less, a total light transmittance of 85% or more, a haze of 10% or less, a yellowness of 5.0 or less, and a 1% weight loss temperature of 275 ° C. That's it.

Because the polyimide resin and acetylcellulose resin contained in the resin composition show compatibility, a transparent film with a small haze can be obtained. In addition, since the polyimide resin and the acetylcellulose resin show compatibility, coloring can be reduced while maintaining the excellent heat resistance of the polyimide, and a transparent film suitable for the cover film of a display can be produced.

[Resin composition]
One embodiment of the present invention is a compatible resin composition containing a polyimide resin and an acetylcellulose resin.

<Polyimide>
Polyimide is obtained by dehydrating and cyclodehydrating polyamic acid obtained by addition polymerization of tetracarboxylic dianhydride (hereinafter sometimes referred to as "acid dianhydride") and diamine. That is, polyimide is a polycondensation product of tetracarboxylic dianhydride and diamine, and has an acid dianhydride-derived structure (acid dianhydride component) and a diamine-derived structure (diamine component).

The polyimide used in the present embodiment is soluble in an organic solvent, and it is particularly preferred that the polyimide is soluble in an organic solvent (methylene chloride, etc.) capable of dissolving the acetylcellulose resin.

(Acid dianhydride)
The polyimide used in this embodiment contains an alicyclic tetracarboxylic dianhydride as an acid dianhydride component. The alicyclic structure of the acid dianhydride component tends to improve the compatibility between the polyimide resin and the acetylcellulose resin. The alicyclic tetracarboxylic dianhydride should just have at least one alicyclic structure, and may have both an alicyclic ring and an aromatic ring in one molecule. The alicyclic ring may be polycyclic and may have a spiro structure.

The alicyclic tetracarboxylic dianhydrides include 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,3-dimethyl cyclobutane-1,2,3,4-tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4, 5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-butanetetracarboxylic dianhydride, meso-butane-1,2,3,4-tetracarboxylic dianhydride, 1,1′- Bicyclohexane-3,3',4,4'tetracarboxylic acid-3,4:3',4'-dianhydride, norbornane-2-spiro-α-cyclopentanone-α'-spiro-2″- norbornane-5,5″,6,6″-tetracarboxylic dianhydride, 2,2′-vinorbornane-5,5′,6,6′tetracarboxylic dianhydride, 3-(carboxymethyl)- 1,2,4-cyclopentanetricarboxylic acid 1,4:2,3-dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride , 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride, cyclohexane-1,4-diylbis(methylene)bis(1 ,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylate), 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, 5,5′-[Cyclohexylidenebis(4,1-phenyleneoxy)]bis-1,3-isobenzofurandione, 5-isobenzofurancarboxylic acid, 1,3-dihydro-1,3-dioxo-, 5 ,5′-[1,4-cyclohexanediylbis(methylene)]ester, bicyclo[2.2.1]heptane-2,3,5,6-tetracarboxylic dianhydride, bicyclo[2.2.2 ] octane-2,3,5,6-tetracarboxylic dianhydride, 3,5,6-tricarboxynorbornane-2-acetic acid 2,3:5,6-dianhydride, decahydro-1,4, 5,8-dimethanonaphthalene-2,3,6,7-tetracarboxylic dianhydride, tricyclo[6.4.0.0(2,7)]dodecane-1,8:2,7-tetracarboxylic dianhydride, octahydro-1H,3H,8H,10H-biphenyleno[4a,4b-c:8a,8b-c′]difuran-1,3,8,10-tetrone, ethylene glycol bis(hydrogenated trimellit acid anhydride) ester, decahydro[2]benzopyrano[6,5,4,-def][2]benzopyran-1,3,6,8-tetrone, and the like.

Among alicyclic tetracarboxylic dianhydrides, 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA), 1,2,3,4- Cyclopentanetetracarboxylic dianhydride (CPDA), 1,2,4,5-cyclohexanetetracarboxylic dianhydride (H-PMDA) or 1,1'-bicyclohexane-3,3',4,4' Tetracarboxylic acid-3,4:3′,4′-dianhydride (H-BPDA) is preferred, with H-PMDA or CBDA being particularly preferred.

From the viewpoint of enhancing the compatibility between the polyimide resin and the acetylcellulose-based resin, the content of the alicyclic tetracarboxylic dianhydride relative to the total amount of 100 mol% of the acid dianhydride component is preferably 10 mol% or more, and 20 mol%. The above is more preferable, and 30 mol% or more is more preferable, and it may be 35 mol% or more, 40 mol% or more, 45 mol% or more, 50 mol% or more, 55 mol% or more, or 60 mol% or more.

Polyimides with a large proportion of alicyclic tetracarboxylic dianhydride in the acid dianhydride component tend to absorb less light in the short wavelength to ultraviolet region of visible light, have excellent transparency, and have excellent light resistance. . In particular, when H-PMDA is used as the alicyclic tetracarboxylic dianhydride, the polyimide resin exhibits high solubility in organic solvents even when the proportion of the alicyclic tetracarboxylic dianhydride is large. , tend to be excellent in compatibility with acetyl cellulose resins.

The polyimide may contain an acid dianhydride other than the alicyclic tetracarboxylic dianhydride as the acid dianhydride component. For example, from the viewpoint of improving the solubility of polyimide resins in organic solvents and the compatibility with cellulose-based resins, in addition to alicyclic tetracarboxylic dianhydrides, fluorine-containing aromatic tetracarboxylic acids are used as acid dianhydride components. It may contain one or more selected from the group consisting of acid dianhydrides, bis(trimellitic anhydride) esters and diphthalic anhydrides having an ether bond.

Fluorine-containing aromatic tetracarboxylic dianhydrides include 2,2-bis(3,4-dicarboxyphenyl)-1,1,1,3,3,3-hexafluoropropane dianhydride, 2,2 -Bis{4-[4-(1,2-dicarboxy)phenoxy]phenyl}-1,1,1,3,3,3-hexafluoropropane dianhydride and the like.

A bis(trimellitic anhydride) ester is represented by the following general formula (1).

X in general formula (1) is an arbitrary divalent organic group, and a carboxy group and a carbon atom of X are bonded at both ends of X. The carbon atoms attached to the carboxy group may form a ring structure. Specific examples of the divalent organic group X include the following (A) to (K).

R ¹ in formula (A) is a fluorine atom, an alkyl group having 1 to 20 carbon atoms, or a fluoroalkyl group having 1 to 20 carbon atoms, and m is an integer of 0 to 4. The group represented by formula (A) is a group obtained by removing two hydroxyl groups from a hydroquinone derivative which may have a substituent on the benzene ring. Hydroquinones having a substituent on the benzene ring include tert-butylhydroquinone, 2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone and the like. In the general formula (1), when X is (A) and m = 0 (that is, the benzene ring has no substituents), the bis(trimellitic anhydride) ester is p-phenylene bis( trimellitate anhydride) (abbreviation: TAHQ).

R ² in formula (B) is a fluorine atom, an alkyl group having 1 to 20 carbon atoms, or a fluoroalkyl group having 1 to 20 carbon atoms, and n is an integer of 0-4. The group represented by formula (B) is a group obtained by removing two hydroxyl groups from biphenol which may have a substituent on the benzene ring. Biphenol derivatives having a substituent on the benzene ring include 2,2′-dimethylbiphenyl-4,4′-diol, 3,3′-dimethylbiphenyl-4,4′-diol, 3,3′,5, 5'-tetramethylbiphenyl-4,4'-diol, 2,2',3,3',5,5'-hexamethylbiphenyl-4,4'-diol and the like.

The group represented by formula (C) is a group obtained by removing two hydroxyl groups from 4,4'-isopropylidenediphenol (bisphenol A). The group represented by formula (D) is a group obtained by removing two hydroxyl groups from resorcinol.

p in formula (E) is an integer from 1 to 10. The group represented by formula (E) is a straight-chain diol having 1 to 10 carbon atoms from which two hydroxyl groups have been removed. Examples of linear diols having 1 to 10 carbon atoms include ethylene glycol and 1,4-butanediol.

The group represented by formula (F) is a group obtained by removing two hydroxyl groups from 1,4-cyclohexanedimethanol.

R ³ in formula (G) is a fluorine atom, an alkyl group having 1 to 20 carbon atoms, or a fluoroalkyl group having 1 to 20 carbon atoms, and q is an integer of 0-4. The group represented by formula (G) is a group obtained by removing two hydroxyl groups from bisphenolfluorene which may have a substituent on the benzene ring having a phenolic hydroxyl group. Examples of the bisphenol fluorene derivative having a substituent on the benzene ring having a phenolic hydroxyl group include biscresol fluorene.

The bis(trimellitic anhydride) ester is preferably an aromatic ester. Among the above (A) to (K), X is preferably (A), (B), (C), (D), (G), (H), or (I). Among them, (A) to (D) are preferred, and (B) a group having a biphenyl skeleton is particularly preferred. When X is a group represented by the general formula (B), from the viewpoint of the solubility of the polyimide in an organic solvent, X is 2,2',3,3' represented by the following formula (B1) , 5,5′-hexamethylbiphenyl-4,4′-diyl.

The acid dianhydride in which X in the general formula (1) is a group represented by the formula (B1) is bis(1,3-dioxo-1,3-dihydroisobenzofuran represented by the following formula (3) -5-carboxylic acid)-2,2′,3,3′,5,5′-hexamethylbiphenyl-4,4′-diyl (abbreviation: TAHMBP).

Diphthalic anhydrides having an ether bond include 3,4'-oxydiphthalic anhydride, 4,4'-oxydiphthalic anhydride, and 4,4'-(4,4'-isopropylidenediphenoxy)diphthalic anhydride. things, etc. 4'-(4,4'-Isopropylidenediphenoxy)diphthalic anhydride (BPADA) is particularly preferable from the viewpoint of solubility of the polyimide resin and compatibility with the acetylcellulose resin.

From the viewpoint of obtaining a polyimide resin having both solubility in an organic solvent and compatibility with an acetyl cellulose resin, alicyclic tetracarboxylic acid dianhydride and fluorine-containing aromatic The total content of tetracarboxylic dianhydride, bis(trimellitic anhydride) ester and diphthalic anhydride having an ether bond is preferably 50 mol% or more, more preferably 60 mol% or more, and 65 mol% or more. is more preferable, and may be 70 mol% or more, 75 mol% or more, 80 mol% or more, 85 mol% or more, 90 mol% or more, or 95 mol% or more.

Polyimide contains acid dianhydride components other than alicyclic tetracarboxylic dianhydride, fluorine-containing aromatic tetracarboxylic dianhydride, bis(trimellitic anhydride) ester and diphthalic anhydride having an ether bond. It may contain an acid dianhydride. Examples of acid dianhydrides other than the above include ethylenetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride, and 2,2′. ,3,3′-benzophenonetetracarboxylic dianhydride, 2,2′,3,3′-biphenyltetracarboxylic dianhydride, pyromellitic dianhydride, 3,3′,4,4′-biphenyl Tetracarboxylic dianhydride, 2,2-bis(3,4-dicarboxyphenyl)propane dianhydride, 2,2-bis(2,3-dicarboxyphenyl)propane dianhydride, bis(3,4 -dicarboxyphenyl)ether dianhydride, bis(3,4-dicarboxyphenyl)sulfone dianhydride, 1,1-bis(2,3-dicarboxyphenyl)ethane dianhydride, bis(2,3- dicarboxyphenyl)methane dianhydride, bis(3,4-dicarboxyphenyl)methane dianhydride, 9,9-bis(3,4-dicarboxyphenyl)fluorene dianhydride), 1,3-bis[ (3,4-dicarboxy)benzoyl]benzene dianhydride, 1,4-bis[(3,4-dicarboxy)benzoyl]benzene dianhydride, 2,2-bis{4-[4-(1, 2-dicarboxy)phenoxy]phenyl}propane dianhydride, 2,2-bis{4-[4-(3,4-dicarboxy)phenoxy]phenyl}propane dianhydride, 2,2-bis{4- [3-(1,2-dicarboxy)phenoxy]phenyl}propane dianhydride, bis{4-[4-(1,2-dicarboxy)phenoxy]phenyl}ketone dianhydride, bis{4-[3 -(1,2-dicarboxy)phenoxy]phenyl}ketone dianhydride, 4,4'-bis[4-(1,2-dicarboxy)phenoxy]biphenyl dianhydride, 4,4'-bis[3 -(1,2-dicarboxy)phenoxy]biphenyl dianhydride, bis{4-[4-(1,2-dicarboxy)phenoxy]phenyl}ketone dianhydride, bis{4-[3-(1, 2-dicarboxy)phenoxy]phenyl}ketone dianhydride, bis{4-[4-(1,2-dicarboxy)phenoxy]phenyl}sulfone dianhydride, bis{4-[3-(1,2- Dicarboxy)phenoxy]phenyl}sulfone dianhydride, bis{4-[4-(1,2-dicarboxy)phenoxy]phenyl}sulfide dianhydride, bis{4-[3-(1,2-dicarboxy ) Phenoxy]phenyl}sulfide dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 1,2,5,6- naphthalenetetracarboxylic dianhydride, 1,2,3,4-benzenetetracarboxylic dianhydride, 3,4,9,10-perylenetetracarboxylic dianhydride, 2,3,6,7-anthracene tetra Carboxylic acid dianhydride, 1,2,7,8-phenanthrenetetracarboxylic acid dianhydride, bis(1,3-dihydro-1,3-dioxo-5-isobenzofurancarboxylic acid)-1,4-phenylene ester are mentioned.

(diamine)
The polyimide used in this embodiment contains a fluoroalkyl-substituted benzidine as a diamine-derived structure. Having a fluoroalkyl-substituted benzidine in the diamine-derived structure tends to achieve both the solubility and transparency of the polyimide resin.

Examples of fluoroalkyl-substituted benzidines include 2-(trifluoromethyl)benzidine, 3-(trifluoromethyl)benzidine, 2,3-bis(trifluoromethyl)benzidine, 2,5-bis(trifluoromethyl)benzidine , 2,6-bis(trifluoromethyl)benzidine, 2,3,5-tris(trifluoromethyl)benzidine, 2,3,6-tris(trifluoromethyl)benzidine, 2,3,5,6-tetrakis (trifluoromethyl)benzidine, 2,2′-bis(trifluoromethyl)benzidine, 3,3′-bis(trifluoromethyl)benzidine, 2,3′-bis(trifluoromethyl)benzidine, 2,2′ , 3-bis (trifluoromethyl) benzidine, 2,3,3'-tris (trifluoromethyl) benzidine, 2,2',5-tris (trifluoromethyl) benzidine, 2,2',6-tris ( trifluoromethyl)benzidine, 2,3′,5-tris(trifluoromethyl)benzidine, 2,3′,6,-tris(trifluoromethyl)benzidine, 2,2′,3,3′-tetrakis(tri fluoromethyl)benzidine, 2,2′,5,5′-tetrakis(trifluoromethyl)benzidine, 2,2′,6,6′-tetrakis(trifluoromethyl)benzidine and the like.

Among them, fluoroalkyl-substituted benzidine having a fluoroalkyl group at the 2-position of biphenyl is preferred, and 2,2'-bis(trifluoromethyl)benzidine (hereinafter referred to as "TFMB") is particularly preferred. By having fluoroalkyl groups at the 2- and 2′-positions of biphenyl, in addition to the reduction in π electron density due to the electron-withdrawing property of the fluoroalkyl groups, the steric hindrance of the fluoroalkyl groups results in the separation of two benzene rings of biphenyl. Since the interbonds are twisted and the planarity of the π-conjugation is lowered, the absorption edge wavelength is shifted to a shorter wavelength, and coloring of the polyimide can be reduced.

The content of the fluoroalkyl-substituted benzidine relative to 100 mol% of the total amount of the diamine component is preferably 50 mol% or more, more preferably 60 mol% or more, still more preferably 70 mol% or more, 80 mol% or more, 85 mol% or more, or 90 mol% or more. It may be mol% or more. A high content of fluoroalkyl-substituted benzidine tends to suppress coloration of the film and increase heat resistance.

The polyimide may contain a diamine other than fluoroalkyl-substituted benzidine as a diamine component. Examples of diamines other than fluoroalkyl-substituted benzidine include p-phenylenediamine, m-phenylenediamine, o-phenylenediamine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether. , 3,3′-diaminodiphenyl sulfide, 3,4′-diaminodiphenyl sulfide, 4,4′-diaminodiphenyl sulfide, 3,3′-diaminodiphenyl sulfone, 3,4′-diaminodiphenyl sulfone, 4,4′ -diaminodiphenyl sulfone, 9,9-bis(4-aminophenyl)fluorene, 3,3'-diaminobenzophenone, 4,4'-diaminobenzophenone, 3,4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 2,2-di(3-aminophenyl)propane, 2,2-di(4-aminophenyl)propane, 2-(3-aminophenyl) -2-(4-aminophenyl)propane, 1,1-di(3-aminophenyl)-1-phenylethane, 1,1-di(4-aminophenyl)-1-phenylethane, 1-(3- aminophenyl)-1-(4-aminophenyl)-1-phenylethane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-aminophenoxy)benzene, 1,4-bis( 3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminobenzoyl)benzene, 1,3-bis(4-aminobenzoyl)benzene, 1,4- bis(3-aminobenzoyl)benzene, 1,4-bis(4-aminobenzoyl)benzene, 1,3-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,3-bis(4-amino -α,α-dimethylbenzyl)benzene, 1,4-bis(3-amino-α,α-dimethylbenzyl)benzene, 1,4-bis(4-amino-α,α-dimethylbenzyl)benzene, 2, 6-bis(3-aminophenoxy)benzonitrile, 2,6-bis(3-aminophenoxy)pyridine, 4,4'-bis(3-aminophenoxy)biphenyl, 4,4'-bis(4-aminophenoxy ) biphenyl, bis[4-(3-aminophenoxy)phenyl]ketone, bis[4-(4-aminophenoxy)phenyl]ketone, bis[4-(3-aminophenoxy)phenyl]sulfide, bis[4-( 4-aminophenoxy)phenyl]sulfide, bis[4-(3-aminophenoxy)phenyl]sulfone, bis[4-(4-aminophenoxy)phenyl]sulfone, bis[4-(3-aminophenoxy)phenyl]ether , bis[4-(4-aminophenoxy)phenyl]ether, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]propane , 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(3-aminophenoxy) )benzoyl]benzene, 1,4-bis[4-(4-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,3 -bis[4-(4-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,4-bis[4-(3-aminophenoxy)-α,α-dimethylbenzyl]benzene, 1,4-bis [4-(4-aminophenoxy)-α,α-dimethylbenzyl]benzene, 4,4′-bis[4-(4-aminophenoxy)benzoyl]diphenyl ether, 4,4′-bis[4-(4- amino-α,α-dimethylbenzyl)phenoxy]benzophenone, 4,4′-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenylsulfone, 4,4′-bis[4-(4 -aminophenoxy)phenoxy]diphenylsulfone, 3,3′-diamino-4,4′-diphenoxybenzophenone, 3,3′-diamino-4,4′-dibiphenoxybenzophenone, 3,3′-diamino-4- phenoxybenzophenone, 3,3′-diamino-4-biphenoxybenzophenone, 6,6′-bis(3-aminophenoxy)-3,3,3′,3′-tetramethyl-1,1′-spirobiindane, 6 ,6'-bis(4-aminophenoxy)-3,3,3',3'-tetramethyl-1,1'-spirobiindane, 1,3-bis(3-aminopropyl)tetramethyldisiloxane, 1, 3-bis(4-aminobutyl)tetramethyldisiloxane, α,ω-bis(3-aminopropyl)polydimethylsiloxane, α,ω-bis(3-aminobutyl)polydimethylsiloxane, bis(aminomethyl) ether , bis(2-aminoethyl)ether, bis(3-aminopropyl)ether, bis(2-aminomethoxy)ethyl]ether, bis[2-(2-aminoethoxy)ethyl]ether, bis[2-(3 -aminoprotoxy)ethyl]ether, 1,2-bis(aminomethoxy)ethane, 1,2-bis(2-aminoethoxy)ethane, 1,2-bis[2-(aminomethoxy)ethoxy]ethane, 1 , 2-bis[2-(2-aminoethoxy)ethoxy]ethane, ethylene glycol bis(3-aminopropyl) ether, diethylene glycol bis(3-aminopropyl) ether, triethylene glycol bis(3-aminopropyl) ether, ethylenediamine, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,12-diaminododecane, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, trans-1,4-diaminocyclohexane , 1,2-di(2-aminoethyl)cyclohexane, 1,3-di(2-aminoethyl)cyclohexane, 1,4-di(2-aminoethyl)cyclohexane, bis(4-aminocyclohexyl)methane , 2,6-bis(aminomethyl)bicyclo[2.2.1]heptane, 2,5-bis(aminomethyl)bicyclo[2.2.1]heptane, 1,4-diamino-2-fluorobenzene, 1,4-diamino-2,3-difluorobenzene, 1,4-diamino-2,5-difluorobenzene, 1,4-diamino-2,6-difluorobenzene, 1,4-diamino-2,3,5 -trifluorobenzene, 1,4-diamino, 2,3,5,6-tetrafluorobenzene, 1,4-diamino-2-(trifluoromethyl)hexane, 1,4-diamino-2,3-bis( trifluoromethyl)benzene, 1,4-diamino-2,5-bis(trifluoromethyl)benzene, 1,4-diamino-2,6-bis(trifluoromethyl)benzene, 1,4-diamino-2, 3,5-tris(trifluoromethyl)benzene, 1,4-diamino, 2,3,5,6-tetrakis(trifluoromethyl)benzene, 2,2′-dimethylbenzidine, 2-fluorobenzidine, 3-fluoro benzidine, 2,3-difluorobenzidine, 2,5-difluorobenzidine, 2,6-difluorobenzidine, 2,3,5-trifluorobenzidine, 2,3,6-trifluorobenzidine, 2,3,5,6 -tetrafluorobenzidine, 2,2'-difluorobenzidine, 3,3'-difluorobenzidine, 2,3'-difluorobenzidine, 2,2',3-trifluorobenzidine, 2,3,3'-trifluorobenzidine , 2,2′,5-trifluorobenzidine, 2,2′,6-trifluorobenzidine, 2,3′,5-trifluorobenzidine, 2,3′,6,-trifluorobenzidine, 2,2′ ,3,3′-tetrafluorobenzidine, 2,2′,5,5′-tetrafluorobenzidine, 2,2′,6,6′-tetrafluorobenzidine, 2,2′,3,3′,6, 6′-hexafluorobenzidine, 2,2′,3,3′,5,5′,6,6′-octafluorobenzidine.

For example, by using diaminodiphenylsulfone as the diamine in addition to the fluoroalkyl-substituted benzidine, the solubility and transparency of the polyimide resin in solvents may be improved. Among diaminodiphenylsulfones, 3,3'-diaminodiphenylsulfone (3,3'-DDS) and 4,4'-diaminodiphenylsulfone (4,4'-DDS) are preferred. 3,3'-DDS and 4,4'-DDS may be used in combination.

The content of diaminodiphenylsulfone relative to 100 mol% of the total amount of diamine may be 1 to 40 mol%, 3 to 30 mol%, or 5 to 25 mol%.

(Preparation of polyimide)
A polyamic acid is obtained as a polyimide precursor by reacting an acid dianhydride and a diamine, and a polyimide is obtained by cyclodehydration (imidization) of the polyamic acid. As described above, by adjusting the composition of the polyimide, that is, the types and ratios of the acid dianhydride and the diamine, the polyimide has transparency and solubility in organic solvents, as well as compatibility with the acetyl cellulose resin. indicates

The method for preparing polyamic acid is not particularly limited, and any known method can be applied. For example, acid dianhydride and diamine are dissolved in approximately equimolar amounts (molar ratio of 95:100 to 105:100) in an organic solvent and stirred to obtain a polyamic acid solution. The concentration of the polyamic acid solution is usually 5-35% by weight, preferably 10-30% by weight. When the concentration is within this range, the polyamic acid obtained by polymerization has an appropriate molecular weight and the polyamic acid solution has an appropriate viscosity.

In the polymerization of polyamic acid, a method of adding an acid dianhydride to a diamine is preferable in order to suppress the ring opening of the acid dianhydride. When adding multiple types of diamines or multiple types of acid dianhydrides, they may be added at once or may be added in multiple batches. Various physical properties of the polyimide can also be controlled by adjusting the addition order of the monomers.

The organic solvent used for polyamic acid polymerization is not particularly limited as long as it does not react with diamines and acid dianhydrides and can dissolve polyamic acid. Examples of organic solvents include urea-based solvents such as methylurea and N,N-dimethylethylurea; sulfoxide or sulfone-based solvents such as dimethylsulfoxide, diphenylsulfone, and tetramethylsulfone; N,N-dimethylacetamide (DMAc); N-dimethylformamide (DMF), N,N'-diethylacetamide, N-methyl-2-pyrrolidone (NMP), γ-butyrolactone, amide solvents such as hexamethylphosphoric triamide, halogenation such as chloroform and methylene chloride Examples include alkyl solvents, aromatic hydrocarbon solvents such as benzene and toluene, and ether solvents such as tetrahydrofuran, 1,3-dioxolane, 1,4-dioxane, dimethyl ether, diethyl ether and p-cresol methyl ether. These solvents are usually used alone or in combination of two or more as needed. DMAc, DMF, NMP and the like are preferably used from the viewpoint of the solubility and polymerization reactivity of polyamic acid.

Polyimide is obtained by dehydration cyclization of polyamic acid. As a method for preparing a polyimide from a polyamic acid solution, there is a method in which a dehydrating agent, an imidization catalyst, etc. are added to the polyamic acid solution and imidization proceeds in the solution. The polyamic acid solution may be heated to accelerate imidization. By mixing a solution containing polyimide produced by imidization of polyamic acid with a poor solvent, the polyimide resin is precipitated as a solid matter. By isolating the polyimide resin as a solid, impurities generated during the synthesis of polyamic acid, residual dehydrating agent, imidization catalyst, etc. can be washed and removed with a poor solvent, resulting in polyimide coloration and yellowness. etc. can be prevented. In addition, by isolating the polyimide resin as a solid, a solvent suitable for film formation, such as a low boiling point solvent, can be applied when preparing a solution for producing a film.

The molecular weight of the polyimide (polyethylene oxide equivalent weight average molecular weight measured by gel filtration chromatography (GPC)) is preferably 10,000 to 300,000, more preferably 20,000 to 250,000, and 40,000 to 200,000 is more preferred. If the molecular weight is too small, the strength of the film may be insufficient. If the molecular weight is too large, the compatibility with the cellulose acetate resin may be poor.

The polyimide is preferably soluble in low boiling point solvents such as ketone solvents and halogenated alkyl solvents. That polyimide exhibits solubility in a solvent means that it dissolves at a concentration of 5% by weight or more. In one embodiment, the polyimide exhibits solubility in methylene chloride. Since methylene chloride has a low boiling point and the residual solvent can be easily removed during film production, the use of a polyimide resin soluble in methylene chloride is expected to improve film productivity.

From the viewpoint of the thermal stability and light stability of the resin composition and film, polyimide preferably has low reactivity. The acid value of polyimide is preferably 0.4 mmol/g or less, more preferably 0.3 mmol/g or less, and even more preferably 0.2 mmol/g or less. The acid value of the polyimide may be 0.1 mmol/g or less, 0.05 mmol/g or less, or 0.03 mmol/g or less. From the viewpoint of reducing the acid value, the polyimide preferably has a high imidization rate. A low acid value tends to increase the stability of the polyimide and improve the compatibility with the acetylcellulose resin.

<Acetyl cellulose resin>
As the acetylcellulose-based resin, diacetylcellulose or triacetylcellulose having an acetyl group substitution degree of 2.0 to 3.0 is preferable. From the viewpoint of compatibility with polyimide and heat resistance, the degree of acetyl substitution of acetylcellulose is preferably 2.4 or more, and may be 2.5 or more, 2.6 or more, 2.7 or more, or 2.8 or more. good.

The acetylcellulose-based resin may have a substituent other than the acetyl group as long as the degree of substitution of the acetyl group is within the above range. Substituents other than the acetyl group include acyl groups such as propionyl group and butyryl group, and alkoxy groups such as methoxy group and ethoxy group.

From the viewpoint of heat resistance of the film, the glass transition temperature of the acetylcellulose resin is preferably 150°C or higher, and may be 160°C or higher or 170°C or higher.

<Preparation of resin composition>
A resin composition is prepared by mixing the polyimide resin and the acetylcellulose resin. Since the polyimide resin and the acetylcellulose-based resin can exhibit compatibility at any ratio, the ratio of the polyimide resin and the acetylcellulose-based resin in the resin composition is not particularly limited. The mixing ratio (weight ratio) of the polyimide resin and the acetylcellulose resin may be 98:2-2:98, 95:5-10:90, or 90:10-15:85. There is a tendency that the higher the proportion of the polyimide resin, the better the heat resistance. The higher the ratio of the acetylcellulose-based resin, the less the film is colored, the higher the transparency, and the more excellent the light resistance tends to be. In order to fully exhibit the effect of improving transparency by mixing the polyimide and the acetylcellulose resin, the ratio of the acetylcellulose resin to the total of the polyimide and the acetylcellulose resin is preferably 10% by weight or more, more preferably 15% by weight. % or more, 20 wt % or more, 25 wt % or more, 30 wt % or more, 35 wt % or more, 40 wt % or more, 45 wt % or more, or 50 wt % or more.

The resin composition may be a mixed solution containing a polyimide resin and an acetylcellulose resin. The method of mixing the resins is not particularly limited, and the resins may be mixed in a solid state or mixed in a liquid to form a mixed solution. A polyimide resin solution and an acetylcellulose-based resin solution may be separately prepared and mixed to prepare a mixed solution of a polyimide resin and an acetylcellulose-based resin.

The solvent for the solution containing the polyimide resin and the acetylcellulose resin is not particularly limited as long as it exhibits solubility in both the polyimide resin and the acetylcellulose resin. Examples of solvents include amide solvents such as N,N-dimethylformamide, N,N-dimethylacetamide and N-methyl-2-pyrrolidone; ether solvents such as 1,4-dioxane and dioxolane; methylene chloride and chloroform. and halogenated alkyl solvents such as 1,1,2,2-tetrachloroethane. Among them, halogenated alkyl solvents are preferable because they have excellent solubility in both polyimide resins and acetylcellulose resins, have a low boiling point, and are easy to remove residual solvents during film production.

For the purpose of improving the workability of the film and imparting various functions, the resin composition (solution) may be blended with organic or inorganic low-molecular-weight compounds, high-molecular-weight compounds (eg, epoxy resin), and the like. The resin composition may contain flame retardants, ultraviolet absorbers, cross-linking agents, dyes, pigments, surfactants, leveling agents, plasticizers, fine particles, sensitizers and the like. The fine particles include organic fine particles such as polystyrene and polytetrafluoroethylene, inorganic fine particles such as colloidal silica, carbon, and layered silicate, and the like, and may have a porous or hollow structure. Fiber reinforcements include carbon fibers, glass fibers, aramid fibers, and the like.

[Molded body and film]
The compositions described above can be used to form various molded bodies. Molding methods include melt methods such as injection molding, transfer molding, press molding, blow molding, inflation molding, calender molding, and melt extrusion molding. A resin composition containing polyimide and an acetylcellulose resin tends to have a lower melt viscosity than polyimide alone, and is excellent in moldability in injection molding, transfer molding, press molding, melt extrusion molding, and the like.

In one embodiment, the molded body is a film. The film forming method may be either a melt method or a solution method, but the solution method is preferred from the viewpoint of producing a film excellent in transparency and uniformity. In the solution method, a film is obtained by coating a support with a solution containing the polyimide resin and the acetylcellulose resin and removing the solvent by drying.

As a method for applying the resin solution onto the support, a known method using a bar coater, a comma coater, or the like can be applied. As the support, a glass substrate, a metal substrate such as SUS, a metal drum, a metal belt, a plastic film, or the like can be used. From the viewpoint of improving productivity, it is preferable to use an endless support such as a metal drum, a metal belt, or a long plastic film as the support and to produce the film by roll-to-roll. When a plastic film is used as the support, a material that does not dissolve in the solvent of the film-forming dope may be appropriately selected.

It is preferable to heat when drying the solvent. The heating temperature is not particularly limited as long as the solvent can be removed and the coloration of the resulting film can be suppressed. The heating temperature may be increased stepwise. In order to increase the removal efficiency of the solvent, the resin film may be peeled off from the support and dried after drying has progressed to some extent. Heating under reduced pressure may be used to facilitate solvent removal.

Acetylcellulose-based films may have low toughness, but the use of a compatible system of polyimide and acetylcellulose-based resin may improve the strength of the film. The film may be stretched in one direction or in multiple directions for the purpose of improving the mechanical strength of the film. When the film is stretched, the polymer chains are oriented in the stretching direction, so that the strength of the film in the in-plane direction is improved, and the occurrence of cracks and splits in the film tends to be suppressed.

The thickness of the film is not particularly limited, and may be set appropriately according to the application. The thickness of the film is, for example, 5-300 μm. From the viewpoint of achieving both self-supporting property and flexibility and making a highly transparent film, the thickness of the film is preferably 10 μm to 100 μm, and may be 30 μm to 90 μm, 40 μm to 85 μm, or 50 μm to 80 μm. . The thickness of the film used as a cover film for displays is preferably 10 μm or more. When the film is stretched, the thickness after stretching is preferably within the above range.

The haze of the film is preferably 10% or less, more preferably 5% or less, even more preferably 4% or less, and may be 3.5% or less, 3% or less, 2% or less, or 1% or less. The lower the haze of the film, the better. As described above, since the polyimide and the acetylcellulose resin exhibit compatibility, a film with low haze and high transparency can be obtained. The resin composition obtained by mixing polyimide and acetylcellulose resin preferably has a haze of 10% or less when a film having a thickness of 10 μm is produced.

The total light transmittance (TT) of the film is preferably 85% or higher, more preferably 87% or higher, even more preferably 89% or higher, particularly preferably 90% or higher, and may be 91% or higher. The higher the TT of the film, the better. As described above, since the polyimide and the acetylcellulose resin show compatibility, a film having a high TT and a high transparency can be obtained. The resin composition obtained by mixing polyimide and acetylcellulose resin preferably has a TT of 85% or more when a film having a thickness of 10 μm is produced. The transmittance of the film at 400 nm is preferably 50% or higher, more preferably 70% or higher, even more preferably 80% or higher, particularly preferably 85% or higher, and may be 90% or higher.

The yellowness index (YI) of the film is preferably 5.0 or less, and may be 2.0 or less or 1.0 or less. As described above, by mixing the polyimide resin and the acetylcellulose resin, a film with less coloration and a smaller YI can be obtained than when the polyimide resin is used alone. The resin composition obtained by mixing polyimide and acetylcellulose resin preferably has a YI of 5.0 or less when a film having a thickness of 10 μm is produced.

It is preferable that the film has a small increase in yellowness ΔYI in a light resistance test. The increase in yellowness ΔYI of the film after a light resistance test in which the film is irradiated with ultraviolet light at an irradiance of 530 W/m ² and a black panel temperature of 63° C. with a cumulative irradiation amount of 40.0 MJ/m ² is preferably 6.0 or less. It is more preferably 5.0 or less, and may be 4.0 or less, 3.0 or less, 2.0 or less, 1.5 or less, or 1.0 or less. The yellowness index YI of the film after the light resistance test is preferably 8.0 or less, more preferably 7.0 or less, 6.0 or less, 5.0 or less, 4.0 or less, 3.0 or less, 2.0 or less. It may be 0 or less or 1.0 or less.

In a compatible system of polyimide resin and cellulose acetate resin, the YI of the film tends to be smaller than in the case of polyimide resin alone, and ΔYI also tends to be smaller. Also, the larger the ratio of the alicyclic acid dianhydride in the acid dianhydride component of the polyimide, the smaller the YI of the film and the smaller the ΔYI.

From the viewpoint of heat resistance, the 1% weight loss temperature (Td1) of the film is preferably 275°C or higher, more preferably 280°C or higher, even more preferably 290°C or higher, and may be 300°C or higher. The 5% weight loss temperature (Td5) of the film is preferably 320°C or higher, more preferably 330°C or higher, even more preferably 340°C or higher, and may be 345°C or higher. In a compatible system of a polyimide resin and an acetylcellulose resin, a film having high Td1 and Td5 and excellent transparency and weather resistance can be obtained without significantly impairing the excellent heat resistance of polyimide.

A film formed from a resin composition containing polyimide and an acetylcellulose resin is less colored and highly transparent, so it is suitable for use as a display material. In particular, films with high mechanical strength can be applied to surface members such as display cover windows. In practical use, the film of the present invention may be provided with an antistatic layer, an easy-adhesion layer, a hard coat layer, an antireflection layer, and the like on the surface.

Hereinafter, the embodiments of the present invention will be described more specifically by showing Examples. In addition, the present invention is not limited to the following examples.

[Production example of polyimide resin]
Dimethylformamide was put into a separable flask and stirred under a nitrogen atmosphere. There, at the ratio (mol%) shown in Table 1, diamine and acid dianhydride are added, stirred for 5 to 10 hours under a nitrogen atmosphere to react, and a polyamic acid solution having a solid content concentration of 18% by weight is prepared. Obtained.

To 100 g of the polyamic acid solution, 5.5 g of pyridine was added as an imidization catalyst and dispersed completely, then 8 g of acetic anhydride was added and stirred at 90°C for 3 hours. After cooling to room temperature, 100 g of 2-propyl alcohol (hereinafter referred to as IPA) was added at a rate of 2 to 3 drops/second while stirring the solution to precipitate polyimide. Further, 150 g of IPA was added, and after stirring for about 30 minutes, suction filtration was performed using a Kiriyama funnel. After washing the obtained solid with IPA, it was dried in a vacuum oven set at 120° C. for 12 hours to obtain a polyimide resin.

[Film production example]
<Examples 1 to 3, Comparative Example 1>
Methylene chloride was mixed with the polyimide (PI) obtained in the above production example and a commercially available triacetyl cellulose resin (cellulose triacetate manufactured by Fujifilm Wako Pure Chemical Industries, degree of substitution: 2.9) at the ratio shown in Table 1. , a methylene chloride solution having a resin content of 11% by weight was prepared. This solution was applied to a non-alkali glass plate, 15 minutes at 60°C, 15 minutes at 90°C, 15 minutes at 120°C, 15 minutes at 150°C, 15 minutes at 180°C, and 15 minutes at 200°C in an air atmosphere. A film having a thickness of about 10 μm was produced by heating and drying under a low temperature.

<Reference Examples 1 to 4>
In Reference Examples 1 to 3, a methylene chloride solution of the polyimide resin used in Examples 1 to 3 was prepared, and a film having a thickness of about 10 μm was produced under the same conditions as above. In Reference Example 4, a methylene chloride solution of triacetyl cellulose resin was prepared, and a film having a thickness of about 10 μm was produced under the same conditions as above.

[evaluation]
<Haze and total light transmittance>
The film was cut into 3 cm squares, and the haze and total light transmittance (TT) were measured according to JIS K7136 and JIS K7361-1 using a haze meter "HZ-V3" manufactured by Suga Test Instruments.

<Yellowness>
The film was cut into 3 cm squares, and the yellowness index (YI) was measured according to JIS K7373 using a spectrophotometer "SC-P" manufactured by Suga Test Instruments.

<Light resistance>
Using a fade meter M6T manufactured by Suga Test Instruments Co., Ltd., a light resistance test was performed by irradiating until the cumulative irradiation dose reached 40.0 MJ/m ² under the conditions of an irradiance of 530 W/m ² and a black panel temperature of 63°C. The YI of the film before and after the light resistance test was measured, and the YI increment ΔYI after the weather resistance test was transferred to three types.

<Heat resistance>
A 1% weight loss temperature (Td1) and a 5% weight loss temperature (Td5) were measured using a simultaneous differential thermal thermogravimetry device (“STA7200” manufactured by Hitachi High-Tech Science). The measurement was performed by weighing 10 mg of the film and increasing the temperature from 30° C. to 400° C. at 10° C./min. Taking the weight at 200° C. as 100%, the temperature at which the weight first fell below 99% was Td1, and the temperature at which the weight first fell below 95% was Td5.

[Evaluation results]
Table 1 shows the compositions of the resins of Examples 1 to 3, Comparative Example 1 and Reference Example 4 (the composition of the polyimide and the mixing ratio with the triacetyl cellulose resin) and the evaluation results of the films.

In Table 1, compounds are described by the following abbreviations.
<Acid dianhydride>
HPMDA: 1,2,4,5-cyclohexanetetracarboxylic dianhydride CBDA: 1,2,3,4-cyclobutanetetracarboxylic dianhydride TAHMBP: bis (1,3-dioxo-1,3-dihydroiso benzofuran-5-carboxylic acid)-2,2',3,3',5,5'-hexamethylbiphenyl-4,4'diyl <diamine>
TFMB: 2,2'-bis (trifluoromethyl) benzidine m-Tol: 2,2'-dimethylbenzidine

The polyimide film of Reference Example 1, which was produced using only the same polyimide resin as that used in Example 1, had a total light transmittance (TT) of 91.7%, whereas the polyimide resin and triacetyl The film of Example 1, which was produced using the composition containing the cellulose resin at a weight ratio of 50:50, had a TT of 92.0% and was excellent in transparency. In addition, the polyimide film of Reference Example 1 had a yellowness increase ΔYI of 1.4 after the weather resistance test, while the film of Example 1 had a ΔYI of 0.4. It can be seen that the film of No. 1 is excellent in light resistance in addition to transparency.

The TT of the polyimide film of Reference Example 2 was 91.5%, while the TT of the film of Example 2 was 91.7%. The TT of the polyimide film of Reference Example 3 was 90.7%, while the TT of the film of Example 3 was 91.2%. These results show that in Examples 2 and 3 as well, the compatible resin composition of the polyimide and the acetylcellulose-based resin has excellent transparency as compared with the polyimide alone.

The ΔYI of the polyimide film of Reference Example 2 was 3.6%, while the ΔYI of the film of Example 2 was 1.7. The ΔYI of the polyimide film of Reference Example 3 was 12.3%, while the ΔYI of the film of Example 3 was 5.6. From these results, it can be seen that in Examples 2 and 3 as well, the compatible resin composition of polyimide and acetylcellulose-based resin has superior light resistance to polyimide alone.

In addition, the films of Examples 1 to 3 had higher Td1 and Td5 than the triacetyl cellulose film of Reference Example 4, and had excellent heat resistance.

In Comparative Example 1, in which a polyimide containing no alicyclic tetracarboxylic dianhydride was used as the tetracarboxylic dianhydride component, the compatibility between the polyimide and triacetyl cellulose was low, resulting in a significant increase in haze.

From the above results, a polyimide containing an alicyclic tetracarboxylic dianhydride as a tetracarboxylic dianhydride component exhibits compatibility with an acetylcellulose resin, and by using a resin composition in which these are mixed, It can be seen that a film having high transparency and excellent light resistance and heat resistance can be obtained.

Claims

Contains polyimide and acetylcellulose resin,
The polyimide contains an alicyclic tetracarboxylic dianhydride as a tetracarboxylic dianhydride component and a fluoroalkyl-substituted benzidine as a diamine component,
Resin composition.
The alicyclic tetracarboxylic dianhydride is 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 1,2,3 ,4-cyclobutanetetracarboxylic dianhydride, and 1,1′-bicyclohexane-3,3′,4,4′tetracarboxylic acid-3,4:3′,4′-dianhydride The resin composition according to claim 1, which is one or more selected.
The resin composition according to claim 1 or 2, wherein the amount of the alicyclic tetracarboxylic dianhydride relative to the total amount of the tetracarboxylic dianhydride component of the polyimide is 10 mol% or more.
The resin composition according to claim 1 or 2, wherein the fluoroalkyl-substituted benzidine is 2,2'-bis(trifluoromethyl)benzidine.
The resin composition according to claim 1 or 2, wherein the amount of the fluoroalkyl-substituted benzidine with respect to the total amount of the diamine component of the polyimide is 50 mol% or more.
The resin composition according to claim 1 or 2, wherein the acetyl cellulose resin has a degree of acetyl substitution of 2.4 or more.
The resin composition according to claim 1 or 2, comprising the polyimide and the acetylcellulose-based resin in a weight ratio ranging from 98:2 to 2:98.
A molded article containing the resin composition according to claim 1 or 2.
A film containing the resin composition according to claim 1 or 2.
10. The composition according to claim 9, which has a thickness of 5 μm or more and 300 μm or less, a total light transmittance of 85% or more, a haze of 10% or less, a yellowness of 5.0 or less, and a 1% weight loss temperature of 275° C. or more. the film.