TW202330710A - Resin composition, molded body and film - Google Patents

Abstract

A resin composition according to the present invention contains a polyimide and an acrylic resin. The polyimide contains, as a tetracarboxylic acid dianhydride component, a fluorine-containing aromatic tetracarboxylic acid dianhydride and a fluorine-free aromatic tetracarboxylic acid dianhydride, while containing a fluoroalkyl-substituted benzidine as a diamine component. Relative to the total content of the tetracarboxylic acid dianhydride component in the polyimide, the content of the fluorine-containing aromatic tetracarboxylic acid dianhydride is preferably 30% by mole to 90% by mole, and the content of the fluorine-free aromatic tetracarboxylic acid dianhydride is preferably 10% by mole to 70% by mole. Relative to the total content of the diamine component in the polyimide, the content of the fluoroalkyl-substituted benzidine is preferably 25% by mole or more.

Description

Resin composition, molded article and film

The present invention relates to a molded article such as a resin composition and a film.

In display devices such as liquid crystals, organic EL (Electroluminescence, electroluminescence), electronic paper, or electronic devices such as solar cells and touch panels, it is required to be thinner or lighter, and furthermore, to be flexible. By replacing the glass material used in these devices with a film material, flexibility, thinning, and weight reduction can be achieved. A transparent polyimide film has been developed as a glass substitute material, which can be used in substrates for displays, cover films, etc.

The usual polyimide film is obtained by the following method: the polyamic acid solution as the polyimide precursor is coated on the support in the form of a film, and subjected to high temperature treatment to remove the solvent. imidization. However, the heating temperature for thermal imidization is high (for example, above 300°C), and coloring (increased yellowness) due to heating is likely to occur, making it difficult to apply to applications requiring high transparency such as cover films for displays.

As a method for producing a highly transparent polyimide film, a method using a polyimide resin that is soluble in an organic solvent and does not require imidization at a high temperature after film formation has been proposed. For example, Patent Document 1 describes that a polyimide containing bis(trimellitic anhydride) ester as a tetracarboxylic dianhydride component is soluble in a low-boiling solvent such as methylene chloride and has excellent transparency and mechanical strength. [Prior Art Literature] [Patent Document]

[Patent Document 1] International Publication No. 2020/004236

[Problem to be solved by the invention]

If polyimide is introduced into a rigid structure, the mechanical strength will increase, but the solubility or transparency in organic solvents will decrease. In the previous transparent polyimide resin, it was difficult to maintain transparency while maintaining transparency. resistance and high mechanical strength. In view of this problem, an object of the present invention is to provide a molded article such as a film having high transparency and sufficient mechanical strength, and a resin composition for producing the same. [Technical means to solve the problem]

The inventors of the present invention have found that polyimide having a specific chemical structure exhibits compatibility with acrylic resins, and by using a resin composition mixed with these, it is possible to produce a highly transparent polyimide without impairing the excellent mechanical strength of polyimide. High film, thus solving the above problems.

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

Polyimide contains fluorine-containing aromatic tetracarboxylic dianhydride and fluorine-free aromatic tetracarboxylic dianhydride as a tetracarboxylic dianhydride component, and contains fluoroalkyl-substituted benzidine as a diamine component.

As a preferable example of the fluorine-containing aromatic tetracarboxylic dianhydride, 4,4'-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) can be mentioned. As a preferred example of fluoroalkyl-substituted benzidine, 2,2'-bis(trifluoromethyl)benzidine may, for example, be mentioned.

Preferable examples of fluorine-free tetracarboxylic dianhydride include: pyromellitic dianhydride (PMDA), 1,2,3,5-pyromellitic dianhydride (MPDA), 3,3' ,4,4'-biphenyltetracarboxylic dianhydride (BPDA), 4,4'-oxydiphthalic anhydride (ODPA), 3,3',4,4'-benzophenone tetracarboxylic acid Dianhydride (BTDA), 4,4'-(4,4'-isopropylidene diphenoxy) diphthalic anhydride (BPADA), 9,9-bis(3,4-dicarboxyphenyl ) stilbene dianhydride (BPAF), and bis(trimellitic anhydride) ester.

Relative to the total amount of tetracarboxylic dianhydride in polyimide, the amount of fluorine-containing aromatic tetracarboxylic dianhydride is preferably 30-90 mole%, and the amount of fluorine-free aromatic tetracarboxylic dianhydride The amount is preferably 10 to 70 mol%. The amount of the fluoroalkyl-substituted benzidine is preferably at least 25 mol% relative to the total amount of diamine components in the polyimide.

In one embodiment of the present invention, the thickness of the film is not less than 5 μm and not more than 300 μm, the total light transmittance is not less than 85%, the haze is not more than 10%, the yellowness is not more than 3.0, and the tensile elastic modulus is not less than 3.0 GPa. Pencil hardness is F or more. [Effect of Invention]

Since the polyimide resin contained in the resin composition exhibits compatibility with the acrylic resin, a transparent film with less haze can be obtained. In addition, since the polyimide resin exhibits compatibility with the acrylic resin, coloring can be reduced without greatly reducing the excellent mechanical strength of the polyimide, and a transparent film suitable for a cover film of a display can be produced.

[resin composition] One embodiment of the present invention is a compatible resin composition comprising a polyimide resin and an acrylic resin.

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

Furthermore, in addition to the method of synthesizing polyimide from acid dianhydride and diamine through polyamic acid, polyimide can also be synthesized by condensation caused by decarboxylation of diisocyanate and acid dianhydride. In the method, the obtained polyimides all have the acid dianhydride structure (tetracarboxylic dianhydride residue) derived from the removal of four carboxyl groups from tetracarboxylic dianhydride, and the structure derived from the removal of two amine groups from diamine. The structure of the resulting diamine (diamine residue). Therefore, when the starting material used for the synthesis of polyimide is not acid dianhydride or diamine, the structure corresponding to the residue of tetracarboxylic dianhydride contained in polyimide is also expressed as "acid dianhydride". "Dianhydride component" refers to a structure corresponding to a diamine residue as a "diamine component".

The polyimide used in this embodiment is preferably soluble in an organic solvent, preferably soluble in N,N-dimethylformamide (DMF) at a concentration of 1% by weight or more. Polyimide is particularly preferably one that is soluble in non-amide solvents other than amide solvents such as DMF.

(acid dianhydride) The polyimide used in this embodiment contains a fluorine-containing aromatic tetracarboxylic dianhydride, and further contains at least one kind of fluorine-free aromatic tetracarboxylic dianhydride as a structure derived from tetracarboxylic dianhydride. The fluorine-containing tetracarboxylic dianhydride and the fluorine-free aromatic tetracarboxylic dianhydride may contain 2 or more types, respectively.

By containing fluorine-containing aromatic tetracarboxylic dianhydride as an acid dianhydride component, there exists a tendency for the transparency of a polyimide and the solubility to an organic solvent to improve. By containing fluorine-free aromatic tetracarboxylic dianhydride as an acid dianhydride component, the mechanical strength of polyimide can be improved. Moreover, the compatibility of a polyimide and an acrylic resin improves depending on the kind of aromatic tetracarboxylic dianhydride which does not contain fluorine.

Examples of fluorine-containing aromatic tetracarboxylic dianhydrides include 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, 2,2-bis[4-(3,4-bis Carboxyphenoxy)phenyl]hexafluoropropane dianhydride, 1,4-difluoropyromellitic dianhydride, 1,4-bis(trifluoromethyl)pyromellitic dianhydride, 4-trifluoromethane Pyromellitic dianhydride, 3,6-bis[3',5'-bis(trifluoromethyl)phenyl]pyromellitic dianhydride, 1-(3',5'-bis(trifluoromethyl) Methyl) phenyl) pyromellitic dianhydride, etc. Among them, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) is particularly preferable from the viewpoint of having both transparency and mechanical strength of polyimide.

Examples of fluorine-free aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride and 1,2,3,5-pyromellitic dianhydride, which are equivalent to one benzene ring bonded with two acid anhydride groups. Acid dianhydride; 2,3,6,7-naphthalene tetracarboxylic acid 2,3:6,7-dianhydride, naphthalene-1,4,5,8-tetracarboxylic dianhydride, triphenyltetracarboxylic Anhydride is equal to an acid dianhydride with 2 anhydride groups bonded by a condensed polycyclic ring; bis(trimellitic anhydride) ester, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 3,4'-oxydiphthalic anhydride, 3,3',4,4 '-Diphenylene tetracarboxylic dianhydride, 4,4'-(4,4'-isopropylidene diphenoxy) diphthalic anhydride, 5,5'-dimethylmethylenebis (phthalic anhydride), 9,9-bis(3,4-dicarboxyphenyl) fluorine dianhydride, 11,11-dimethyl-1H-difluoro[3,4-b:3',4 '-i]𠮿 -1,3,7,9(11H)-Tetorone, 1,4-bis(3,4-dicarboxyphenoxy)phthalic anhydride, 4-(2,5-dioxytetrahydrofuran-3- base)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic dianhydride, ethylene glycol bis(trimellitic anhydride), N,N'-(9H-terpinene-9-ylidene Di-4,1-phenylene)bis[1,3-dihydro-1,3-dioxo-5-isobenzofuramide], N,N'-[[2,2,2 -Trifluoro-1-(trifluoromethyl)ethylene]bis(6-hydroxy-3,1-phenylene)]bis[1,3-dihydro-1,3-dihydro-5- Isobenzofuryl carboxamide], 2,2-bis(4-hydroxyphenyl)propane dibenzoate-3,3',4,4'-tetracarboxylic dianhydride are equal to different aromatic ring bonds An acid dianhydride with an anhydride group.

Among them, from the viewpoint of the transparency and solubility of polyimide, and the compatibility with acrylic resins, pyromellitic dianhydride ( PMDA), 1,2,3,5-mellitic acid dianhydride (MPDA), 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), 4,4'-oxydiphthalic acid dianhydride Diformic anhydride (ODPA), 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA), 4'-(4,4'-isopropylidene diphenoxy) di-o Phthalic anhydride (BPADA), 9,9-bis(3,4-dicarboxyphenyl) fluorine dianhydride (BPAF), bis(trimellitic anhydride) ester.

Bis(trimellitic anhydride) ester is represented by following general formula (1).

[chemical 1]

X in the general formula (1) is any divalent organic group, and a carboxyl group and a carbon atom of X are bonded to both ends of X. A carbon atom bonded to a carboxyl group may form a ring structure. Specific examples of the divalent organic group X include the following (A) to (K).

[Chem 2]

R ¹ in formula (A) is a fluorine atom, an alkyl group having 1-20 carbon atoms, or a fluoroalkyl group having 1-20 carbon atoms, and m is an integer of 0-4. 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 a benzene ring. Examples of hydroquinone having a substituent on the benzene ring include tert-butylhydroquinone, 2,5-di-tert-butylhydroquinone, 2,5-di-tertiary Amyl Hydroquinone etc. In the general formula (1), when X is (A) and m=0 (that is, there is no substituent on the benzene ring), the bis(trimellitic anhydride) ester is terephthalic bis(trimellitic anhydride) ( Abbreviation: TAHQ).

R ² in formula (B) is a fluorine atom, an alkyl group having 1-20 carbon atoms, or a fluoroalkyl group having 1-20 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. Examples of biphenol derivatives having substituents 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, etc.

The group represented by formula (C) is a group obtained by removing two hydroxyl groups from 4,4'-isopropylidene diphenol (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 of 1-10. The group represented by the formula (E) is a group obtained by removing two hydroxyl groups from a linear diol having 1 to 10 carbon atoms. Ethylene glycol, 1, 4- butanediol etc. are mentioned as C1-C10 linear diol.

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 1-20 carbon atoms, or a fluoroalkyl group having 1-20 carbon atoms, and q is an integer of 0-4. The group represented by the formula (G) is a group obtained by removing two hydroxyl groups from bisphenol fluorine which may have a substituent on a benzene ring having a phenolic hydroxyl group. As the bisphenol oxale derivative having a substituent on the benzene ring having a phenolic hydroxyl group, biscresyl stilbene and the like may, for example, be mentioned.

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

[Chem 3]

In the general formula (1), X is the acid dianhydride of the group represented by the formula (B1) is the bis(1,3-two side oxygen-1,3-dihydroisobenzofuran represented by the following formula (3) -5-carboxylic acid)-2,2',3,3',5,5'-hexamethylbiphenyl-4,4'-diyl (abbreviation: TAHMBP).

[chemical 4]

From the perspective of improving the compatibility between polyimide resin and acrylic resin, and having both the transparency and mechanical strength of molded products such as films formed from the resin composition, relative to 100 moles of the total amount of acid dianhydride components %, the content of fluorine-containing aromatic tetracarboxylic dianhydride is preferably 30-90 mol%, more preferably 35-80 mol%, and still more preferably 40-75 mol%. From the same point of view, the content of fluorine-free aromatic tetracarboxylic dianhydride is preferably 10-70 mol%, more preferably 20-65 mol%, relative to 100 mol% of the total amount of acid dianhydride. ear %, and more preferably 25 to 60 mole %.

As mentioned above, PMDA, MPDA, BPDA, ODPA, BTDA, BPADA, BPAF, and bis(trimellitic anhydride) ester are preferable as the fluorine-free aromatic tetracarboxylic dianhydride, and the total of these is preferably 10-70 mol%, more preferably 20-65 mol%, still more preferably 25-60 mol%.

The amount of the fluorine-free aromatic tetracarboxylic dianhydride required to achieve both compatibility with the acrylic resin and mechanical strength may vary depending on the type of the acid dianhydride. For example, since PMDA has a rigid structure, even a small amount greatly contributes to the improvement of mechanical strength, but if the amount of PMDA exceeds 70 mol%, there will be a problem with the solubility of polyimide in organic solvents or the solubility of acrylic resins. Tendency to decrease compatibility. On the other hand, BPADA has a structure in which two benzene rings bonded with acid anhydride groups are bonded through 4,4'-isopropylidene diphenoxy group, and the molecular chain has high flexibility, so even BPADA When the amount is large, it is not easy to reduce the solubility or compatibility in organic solvents. By using PMDA and BPADA together as fluorine-free aromatic tetracarboxylic dianhydride, the mixture of polyimide resin and acrylic resin can also show compatibility in low-boiling solvents such as methylene chloride. In addition, molded articles such as films formed of a mixture of polyimide resin and acrylic resin containing PMDA and BPADA as fluorine-free aromatic tetracarboxylic dianhydrides are also excellent in mechanical strength.

From the viewpoint of obtaining polyimide having both solubility in organic solvents and compatibility with acrylic resins, fluorine-containing aromatic tetracarboxylic The total content of acid dianhydride and fluorine-free aromatic tetracarboxylic dianhydride, that is, the content of aromatic tetracarboxylic dianhydride is preferably at least 80 mol%, more preferably at least 85 mol%, and can also be 90 mol More than ear %, more than 95 mole % or 100%. Relative to 100 mol% of the total amount of acid dianhydride components, the total content of 6FDA, PMDA, MPDA, BPDA, ODPA, BTDA, BPADA, BPAF, and bis(trimellitic anhydride) ester is preferably more than 80 mol%. It is preferably at least 85 mol%, and may be at least 90 mol%, at least 95 mol%, or 100%. As bis(trimellitic anhydride) ester, TAHQ and TAHMBP are preferable, and TAHMBP is especially preferable.

The polyimide may contain non-aromatic tetracarboxylic dianhydride as a structure derived from tetracarboxylic dianhydride. As an example of a non-aromatic tetracarboxylic dianhydride, an alicyclic tetracarboxylic dianhydride is mentioned.

As the alicyclic tetracarboxylic dianhydride, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic dianhydride, 1, 2,4,5-Cyclohexanetetracarboxylic dianhydride, 1,1'-bicyclohexane-3,3',4,4'tetracarboxylic acid-3,4,3',4'-dianhydride , Nor-2-spiro-α-cyclopentanone-α'-spiro-2''-nor-2-5,5'',6,6''-tetracarboxylic dianhydride, 2,2' -Norrane-5,5',6,6'tetracarboxylic dianhydride, etc. From the viewpoint of the transparency and mechanical strength of polyimide, the alicyclic tetracarboxylic dianhydride is preferably 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2, 3,4-cyclopentane tetracarboxylic dianhydride, or 1,2,4,5-cyclohexane tetracarboxylic dianhydride, especially 1,2,3,4-cyclobutane tetracarboxylic dianhydride .

As an example of tetracarboxylic dianhydride other than the above, ethylene tetracarboxylic dianhydride, butane tetracarboxylic dianhydride, etc. are mentioned.

(diamine) The polyimide used in this embodiment contains a fluoroalkyl-substituted benzidine as a diamine component.

Examples of fluoroalkyl-substituted benzidine include: 2-fluorobenzidine, 3-fluorobenzidine, 2,3-difluorobenzidine, 2,5-difluorobenzidine, 2,6-difluorobenzidine Benzidine, 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 Fluorobenzidine, 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, 2-(trifluoromethyl)benzidine, 3-(trifluoromethyl)biphenyl Aniline, 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-tris(trifluoromethyl)benzidine Methyl)benzidine, 2,3,3'-tris(trifluoromethyl)benzidine, 2,2',5-tris(trifluoromethyl)benzidine, 2,2',6-tris(trifluoromethyl)benzidine Fluoromethyl)benzidine, 2,3',5-tris(trifluoromethyl)benzidine, 2,3',6,-tris(trifluoromethyl)benzidine, 2,2',3,3 '-tetra(trifluoromethyl)benzidine, 2,2',5,5'-tetrakis(trifluoromethyl)benzidine, 2,2',6,6'-tetrakis(trifluoromethyl)benzidine Aniline etc.

Among the fluoroalkyl-substituted benzidines, the fluoroalkyl group of the fluoroalkyl-substituted benzidine is preferably a perfluoroalkyl group from the viewpoint of achieving both solubility and transparency of the polyimide. The perfluoroalkyl group is preferably a trifluoromethyl group. Among them, perfluoroalkyl-substituted benzidine having a perfluoroalkyl group at the 2-position of biphenyl is preferable from the viewpoint of solubility in organic solvents of polyimide and compatibility with acrylic resins, Especially preferred is 2,2'-bis(trifluoromethyl)benzidine (hereinafter referred to as "TFMB"). Since the 2-position and 2'-position of biphenyl have a trifluoromethyl group, in addition to the electron-withdrawing properties of the trifluoromethyl group, the π-electron density decreases, and the steric hindrance of the trifluoromethyl group also makes the two phenyl groups of biphenyl The bond between the rings is twisted, and the planarity of π-conjugation is reduced, so the wavelength of the absorption end is shifted to a short wavelength, which can reduce the coloring of polyimide.

Relative to 100 mol% of the total amount of diamine components, the content of fluoroalkyl-substituted benzidine is preferably at least 25 mol%, more preferably at least 30 mol%, further preferably at least 40 mol%, especially preferably It is 50 mol% or more, and may be 60 mol% or more, 70 mol% or more, 80 mol% or more, 85 mol% or more, or 90 mol% or more. When the content of fluoroalkyl-substituted benzidine is high, coloring of the film is suppressed, and mechanical strength such as pencil hardness and elastic modulus tends to increase.

The polyimide may contain diamines other than fluoroalkyl-substituted benzidine as structures derived from diamines. Examples of diamines other than fluoroalkyl-substituted benzidine include: 2,4-diaminotoluene, 2,5-diaminotoluene, p-phenylenediamine, m-phenylenediamine, ortho-phenylenediamine Amine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide , 3,4'-diaminodiphenylsulfide, 4,4'-diaminodiphenylsulfide, 3,3'-diaminodiphenylsulfide, 3,4'-diaminodiphenylsulfide , 4,4'-diaminodiphenylphenone, 9,9-bis(4-aminophenyl) terpene, 3,3'-diaminobenzophenone, 4,4'-diaminodiphenone Benzophenone, 3,4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 4,4'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane Benzene, 2,2-bis(3-aminophenyl)propane, 2,2-bis(4-aminophenyl)propane, 2-(3-aminophenyl)-2-(4-amine phenyl)propane, 1,1-bis(3-aminophenyl)-1-phenylethane, 1,1-bis(4-aminophenyl)-1-phenylethane, 1-(3 -aminophenyl)-1-(4-aminophenyl)-1-phenylethane, 1,3-bis(3-aminophenoxy)benzene, 1,3-bis(4-amino Phenoxy)benzene, 1,4-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene Acyl)benzene, 1,3-bis(4-aminobenzoyl)benzene, 1,4-bis(3-aminobenzoyl)benzene, 1,4-bis(4-aminobenzoyl)benzene Formyl)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)benzene base] ketone, bis[4-(3-aminophenoxy)phenyl]sulfide, bis[4-(4-aminophenoxy)phenyl]sulfide, bis[4-(3-amine ylphenoxy)phenyl]pyridine, bis[4-(4-aminophenoxy)phenyl]pyridine, 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-aminophenyl oxy)phenyl]propane, 1,3-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,3-bis[4-(4-aminophenoxy)benzene Formyl]benzene, 1,4-bis[4-(3-aminophenoxy)benzoyl]benzene, 1,4-bis[4-(4-aminophenoxy)benzoyl Base] 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]diphenylphenoxide, 4,4'-bis[4-(4-aminophenoxy)phenoxy]diphenylphenoxide, 3,3'-diphenoxy Amino-4,4'-diphenoxybenzophenone, 3,3'-diamino-4,4'-diphenoxybenzophenone, 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'-spirobiindan, 1,3-bis(3-aminopropyl)tetramethyldisiloxane, 1,3-bis(4-aminobutyl)tetramethyldisiloxane alkane, 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-aminoethyl) oxy)ethyl]ether, bis[2-(3-aminopropoxy)ethyl]ether, 1,2-bis(aminomethoxy)ethane, 1,2-bis(2-amine ethoxy)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, ethylene glycol bis(3-aminopropyl) ether, Amine, 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-diaminodecane Dioxane, 1,2-diaminocyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, trans-1,4-diaminocyclohexane, 1,2-bis(2-aminoethyl)cyclohexane, 1,3-bis(2-aminoethyl)cyclohexane, 1,4-bis(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 alkanes, 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)benzene, 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(trifluoro Methyl)benzene, 1,4-diamino, 2,3,5,6-tetrakis(trifluoromethyl)benzene.

For example, by using diaminodiphenylamine as a diamine in addition to fluoroalkyl-substituted benzidine, the solubility or transparency of polyimide in an organic solvent 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 can be used together.

Relative to 100 mol% of the total amount of diamines, the content of diaminodiphenylphenone can be 1-40 mol%, 3-30 mol%, or 5-25 mol%.

(Preparation of polyimide) Polyamic acid as a precursor of polyimide can be obtained through the reaction of acid dianhydride and diamine, and polyimide can be obtained through dehydration and cyclization (imidization) of polyamic acid. By adjusting the composition of polyimide, that is, the types and ratios of acid dianhydride and diamine, polyimide has transparency and solubility in organic solvents, and exhibits compatibility with acrylic resins.

The method for producing polyamide acid is not particularly limited, and all known methods can be applied. For example, a polyamic acid solution can be obtained by dissolving acid dianhydride and diamine in an organic solvent in approximately equal molar amounts (95:100 to 105:100 molar ratio) and stirring. The concentration of the polyamide acid solution is usually 5 to 35% by weight, preferably 10 to 30% by weight. In the case of the concentration in this range, the polyamic acid obtained by polymerization has an appropriate molecular weight, and the polyamic acid solution has an appropriate viscosity.

When polymerizing polyamic acid, in order to suppress the ring-opening of acid dianhydride, the method of adding acid dianhydride to diamine is preferable. When adding plural kinds of diamines or plural kinds of acid dianhydrides, they may be added at one time, or may be divided and added several times. The physical properties of polyimide can also be controlled by adjusting the order of adding monomers.

The organic solvent used for polymerizing polyamic acid is not particularly limited, as long as it does not react with diamine and acid dianhydride and can dissolve polyamic acid. As the organic solvent, for example: urea solvents such as methyl urea and N,N-dimethylethyl urea; , N-dimethylacetamide (DMAc), N,N-dimethylformamide (DMF), N,N'-diethylacetamide, N-methyl-2-pyrrolidone ( Amide-based solvents such as NMP), γ-butyrolactone, and hexamethyltriamide phosphate; halogenated alkyl-based solvents such as chloroform and methylene chloride; aromatic hydrocarbon-based solvents such as benzene and toluene, tetrahydrofuran, 1,3-bis Oxolane, 1,4-dioxane, dimethyl ether, diethyl ether, p-cresol methyl ether and other ether solvents. Usually, these solvents are used individually or in appropriate combination of 2 or more types as needed. From the viewpoint of solubility and polymerization reactivity of polyamic acid, it is preferable to use DMAc, DMF, NMP, and the like.

Polyimides can be obtained by dehydration cyclization of polyamic acid. As a method of preparing polyimide from a polyamic acid solution, a method of adding a dehydrating agent, an imidization catalyst, etc. to the polyamic acid solution, and performing imidization in the solution may be mentioned. The polyamic acid solution can be heated to facilitate imidization. By mixing a solution containing polyimide produced by imidation of polyamic acid and a poor solvent, polyimide resin is precipitated as a solid. By isolating the polyimide resin in the form of solid matter, it can be washed with a poor solvent to remove impurities generated during the synthesis of polyamic acid, or residual dehydrating agents and imidization catalysts, etc., which can prevent polyimide Imide coloring or yellowness increase, etc. 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 used when preparing a solution for film formation.

The molecular weight of the polyimide (weight average molecular weight in terms of polyethylene oxide measured by gel filtration chromatography (GPC)) is preferably 10,000 to 300,000, more preferably 20,000 to 250,000, still more preferably 40,000 ~200,000. When the molecular weight is too small, the strength of the film may be insufficient. When the molecular weight is too large, the compatibility with the acrylic resin may be poor.

The polyimide resin is preferably soluble in non-amide-based solvents such as ketone-based solvents and halogenated alkyl-based solvents. The fact that the polyimide resin exhibits solubility in a solvent means that it dissolves at a concentration of 5% by weight or more. In one embodiment, the polyimide resin exhibits solubility in methylene chloride. Since dichloromethane has a low boiling point, it is easy to remove the residual solvent during film formation. Therefore, by using a polyimide resin soluble in dichloromethane, it is expected that the productivity of the film will be improved.

From the viewpoint of thermal stability and light stability of the resin composition and film, polyimide is preferably less reactive. The acid value of polyimide is preferably at most 0.4 mmol/g, more preferably at most 0.3 mmol/g, still more preferably at most 0.2 mmol/g. The acid value of 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 making the acid value smaller, polyimide preferably has a high imidization rate. There exists a tendency for the stability of polyimide to improve and the compatibility with an acrylic resin to improve because an acid value is small.

＜Acrylic resin＞ Examples of acrylic resins include poly(meth)acrylates such as polymethyl methacrylate, methyl methacrylate-(meth)acrylic acid copolymer, methyl methacrylate-(meth)acrylate copolymer substances, methyl methacrylate-acrylate-(meth)acrylic acid copolymer, methyl (meth)acrylate-styrene copolymer, etc. The acrylic resin may be modified to introduce a glutarimide structural unit or a lactone ring structural unit. The stereoregularity of the polymer is not particularly limited, and may be any of the homogeneous type, the opposite type, and the heterogeneous type.

From the viewpoint of transparency, compatibility with polyimide, and mechanical strength of molded products such as films, the acrylic resin is preferably one containing methyl methacrylate as a main structural unit. The amount of methyl methacrylate in the acrylic resin relative to the total amount of monomer components is preferably 60% by weight or more, and may be 70% by weight or more, 80% by weight or more, 85% by weight or more, 90% by weight or more or 95% by weight. % by weight or more. The acrylic resin may be a homopolymer of methyl methacrylate.

As described above, the acrylic resin may have a glutarimide structure or a lactone ring structure introduced therein. Such a modified polymer is preferably one in which a glutarimide structure or a lactone ring structure is introduced into an acrylic polymer having a methyl methacrylate content within the above-mentioned range. That is, in the acrylic resin modified by introducing a glutarimide structure or a lactone ring structure, the total amount of methyl methacrylate and the modified structure of methyl methacrylate is preferably 60% by weight or more , can also be 70% by weight or more, 80% by weight or more, 85% by weight or more, 90% by weight or more, or 95% by weight or more. The modified polymer may have a glutarimide structure or a lactone ring structure introduced into a homopolymer of methyl methacrylate.

The glass transition temperature of the acrylic resin tends to increase by introducing a glutarimide structure or a lactone ring structure into an acrylic polymer such as methyl methacrylate. Also, since the acrylic resin modified with glutarimide contains an imide structure, compatibility with polyimide may be improved.

The acrylic resin having a glutarimide structure can be obtained by heating and melting polymethyl methacrylate resin and treating it with an imidization agent, as described in Japanese Patent Application Laid-Open No. 2010-261025, for example. When the acrylic polymer has a glutarimide structure, the glutarimide content may be 3% by weight or more, 5% by weight or more, 10% by weight or more, 20% by weight or more, 30% by weight or more, or 50% by weight. % by weight or more.

The content of glutarimide is calculated as follows: the import rate of glutarimide ^structure (imide conversion rate), the imidization rate was converted by weight. For example, in methyl methacrylate introduced with a glutarimide structure, the area A of the peak (around 3.5 to 3.8 ppm) derived from the O-CH ₃ proton of methyl methacrylate, and the area A derived from the glutarimide The area B of the peak (around 3.0 to 3.3 ppm) of the N-CH ₃ proton of the amine is used to obtain the imidization ratio Im=B/(A+B).

From the viewpoint of heat resistance of the film, the glass transition temperature of the acrylic resin is preferably 90°C or higher, more preferably 100°C or higher, further preferably 110°C or higher, and may be 115°C or higher or 120°C or higher.

The weight average molecular weight (in terms of polystyrene) of the acrylic resin is preferably from 5,000 to 500,000, more preferably from 10,000, from the viewpoint of solubility in organic solvents, compatibility with the aforementioned polyimide, and film strength. -300,000, more preferably 15,000-200,000.

From the viewpoint of thermal stability and light stability of the resin composition and film, the acrylic resin preferably has less reactive functional groups such as ethylenically unsaturated groups and carboxyl groups. The iodine value of the acrylic resin is preferably below 10.16 g/100 g (0.4 mmol/g), more preferably below 7.62 g/100 g (0.3 mmol/g), and even more preferably below 5.08 g/100 g (0.2 mmol/g). /g) or less. The iodine value of the acrylic resin may be 2.54 g/100 g (0.1 mmol/g) or less or 1.27 g/100 g (0.05 mmol/g) or less. The acid value of the acrylic resin is preferably at most 0.4 mmol/g, more preferably at most 0.3 mmol/g, still more preferably at most 0.2 mmol/g. The acid value of the acrylic resin may be 0.1 mmol/g or less, 0.05 mmol/g or less, or 0.03 mmol/g or less. When the acid value is small, the stability of the acrylic resin is improved, and the compatibility with polyimide tends to be improved.

＜Preparation of resin composition＞ The above polyimide resin and acrylic resin were mixed to prepare a resin composition. The polyimide resin and the acrylic resin can exhibit compatibility at any ratio, so the ratio of the polyimide resin to the acrylic resin in the resin composition is not particularly limited. The mixing ratio (weight ratio) of the polyimide resin and the acrylic resin may be 98:2-2:98, 95:5-10:90, or 90:10-15:85. The higher the ratio of the polyimide resin, the higher the elastic modulus and pencil hardness of the film, and the more excellent the mechanical strength tends to be. The higher the ratio of the acrylic resin, the less the coloring of the film and the higher the transparency tends to be. In order to give full play to the transparency improvement effect brought by mixing polyimide resin and acrylic resin, the ratio of acrylic resin to the total of polyimide resin and acrylic resin is preferably 10% by weight or more. 15% by weight or more, 20% by weight or more, 25% by weight or more, 30% by weight or more, 35% by weight or more, 40% by weight or more, 45% by weight or more, 50% by weight or more, 60% by weight or more, or 70% by weight or more .

Polyimide is a polymer with a special molecular structure, generally has low solubility in organic solvents, and does not show compatibility with other polymers. In this embodiment, the polyimide contains a fluoroalkyl-substituted benzidine as a diamine component, and in addition to a fluorine-containing aromatic acid dianhydride, also contains a fluorine-free aromatic acid dianhydride as an acid dianhydride component. , whereby the polyimide resin exhibits high solubility to organic solvents, and exhibits compatibility with acrylic resins, thereby exhibiting excellent mechanical strength.

The resin composition including the polyimide resin and the acrylic resin preferably has a single glass transition temperature in differential scanning calorimetry (DSC) and/or dynamic viscoelasticity measurement (DMA). When the resin composition has a single glass transition temperature, it can be considered that the polyimide resin and the acrylic resin are completely compatible. Films comprising polyimide resins and acrylic resins also preferably have a single glass transition temperature.

The resin composition may also be a mixed solution including polyimide resin and acrylic resin. The method of mixing the resins is not particularly limited, and they may be mixed in a solid state or mixed in a liquid to prepare a mixed solution. The polyimide resin solution and the acrylic resin solution can be prepared separately, and the two are mixed to prepare a mixed solution of the polyimide resin and the acrylic resin.

The solvent of the solution containing the polyimide resin and the acrylic resin is not particularly limited as long as it exhibits solubility in both the polyimide resin and the acrylic resin. Examples of solvents include amide-based solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone; tetrahydrofuran, 1 , 4-dioxane and other ether solvents; acetone, methyl ethyl ketone, methyl propyl ketone, methyl isopropyl ketone, methyl isobutyl ketone, diethyl ketone, cyclopentanone, cyclohexane Ketone-based solvents such as ketone and methylcyclohexanone; halogenated alkyl-based solvents such as chloroform, 1,2-dichloroethane, 1,1,2,2-tetrachloroethane, chlorobenzene, dichlorobenzene, and methylene chloride solvent.

From the viewpoint of the solubility of the polyimide resin and the compatibility between the polyimide resin and the acrylic resin in the solution, an amide-based solvent is preferred. On the other hand, from the viewpoint of solvent removability when forming a molded product such as a film, a non-amide solvent with a low boiling point is preferred because it has excellent solubility in both polyimide resin and acrylic resin and has a boiling point It is relatively low, and it is preferable to use a ketone-based solvent and a halogenated alkyl-based solvent in terms of easy removal of the residual solvent during film formation. Due to the high compatibility between the polyimide resin and the acrylic resin, the above resin composition can also show compatibility in non-amide solvents with low boiling points such as ketone solvents and halogenated alkyl solvents.

Especially when polyimide contains PMDA or MPDA equal to 1 aromatic ring bonded with 2 acid anhydride groups, fluorine-free aromatic tetracarboxylic dianhydride as the acid dianhydride component, non-acyl dianhydride with low boiling point Among amine solvents, the compatibility with acrylic resin tends to be excellent. The polyimide in the resin composition may have PMDA and/or MPDA as an acid dianhydride component. The total amount of PMDA and MPDA may be 5-65 weight%, 10-60 weight%, 15-55 weight% or 20-50 weight% with respect to the total amount of the acid dianhydride component of polyimide.

As mentioned above, the polyimide in a resin composition can contain PMDA and BPADA as a fluorine-free aromatic tetracarboxylic dianhydride component. The total amount of PMDA and BPADA may be 30-70 weight%, 40-65 weight%, or 45-60 weight% with respect to the total amount of the acid dianhydride component of polyimide. The amount of BPADA may be 5-50 mol %, 10-40 mol %, 15-35 mol % or 20-30 mol % relative to the total amount of the acid dianhydride component of polyimide.

For the purpose of improving the processability of the film or imparting various functions, organic or inorganic low-molecular compounds, high-molecular compounds (such as epoxy resins), etc. can be formulated in the resin composition (solution). The resin composition may contain flame retardants, ultraviolet absorbers, crosslinking agents, dyes, pigments, surfactants, leveling agents, plasticizers, fine particles, sensitizers, and the like. Microparticles include organic microparticles such as polystyrene and polytetrafluoroethylene, inorganic microparticles such as colloidal silicon dioxide, carbon, and layered silicate, and may have a porous or hollow structure. Fiber reinforcement materials include carbon fiber, glass fiber, aramid fiber, etc.

[Molded body and film] The above composition can be used to form various shaped bodies. The molding method may, for example, be a melting method such as injection molding, transfer molding, press molding, blow molding, inflation molding, calender molding, or melt extrusion molding. Resin compositions containing polyimide resins and acrylic resins tend to have lower melt viscosity than polyimide alone, and are suitable for injection molding, transfer molding, pressure molding, melt extrusion molding, etc. excellent.

Also, the solution of the resin composition containing the polyimide resin and the acrylic resin tends to have a lower solution viscosity than a solution of the polyimide resin alone at the same solid content concentration. Therefore, the operability such as transporting the solution is excellent, and the applicability is high, which contributes to the reduction of the unevenness of the film thickness and the like.

In one embodiment, the formed body is a film. The forming method of the film may be either a melt method or a solution method, and the solution method is preferable from the viewpoint of producing a film excellent in transparency and uniformity. In the solution method, a film is obtained by coating the above-mentioned solution containing polyimide resin and acrylic resin on a support, and drying and removing the solvent.

As a method of coating the resin solution on the support, a known method using a bar coater, a chip coater, or the like can be applied. A glass substrate, a metal substrate such as SUS (Steel Use Stainless, Japan Stainless Steel Standard), a metal roll, a metal belt, a plastic film, or the like can be used as the support. From the viewpoint of improving productivity, it is preferable to manufacture the film by a roll-to-roll method using an endless support such as a metal roll or a metal belt, or a long plastic film as a support. In the case of using a plastic film as a support, materials that are insoluble in the solvent used for film formation and doping can be appropriately selected.

It is preferable to heat when drying a solvent. The heating temperature is not particularly limited, as long as the solvent can be removed and the coloring of the obtained film can be suppressed. It is appropriately set from room temperature to about 250°C, preferably 50°C to 220°C. The heating temperature can be raised step by step. In order to improve the removal efficiency of the solvent, after drying to a certain extent, the resin film may be peeled from the support and dried. To facilitate solvent removal, heating can be performed under reduced pressure.

Acrylic films may have low toughness, but the strength of the film may be improved by using a compatible system of polyimide resin and acrylic resin.

The thickness of the film is not particularly limited, and can be appropriately set according to the application. The thickness of the film is, for example, 5 to 300 μm. From the viewpoint of making a self-sustaining, flexible and highly transparent film, the thickness of the film is preferably 20 μm to 100 μm, and can also be 30 μm to 90 μm, 40 μm to 85 μm, Or 50 μm ~ 80 μm. The thickness of the film used as a cover film for a display is preferably 50 μm or more.

The haze of the film is preferably 10% or less, more preferably 5% or less, still 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 mentioned above, polyimide resin and acrylic resin exhibit compatibility, so a film with low haze and high transparency can be obtained. The resin composition in which the polyimide resin and the acrylic resin are mixed preferably has a haze of 10% or less when forming a film with a thickness of 50 μm.

The light transmittance of the film at a wavelength of 400 nm is preferably 45% or more, more preferably 50% or more, further preferably 55% or more, and may be 60% or more, 65% or more or 70% or more. The yellowness (YI) of the film is preferably 3.0 or less, more preferably 2.5 or less, and may be 2.0 or less, 1.5 or less, or 1.0 or less. As mentioned above, by mixing polyimide resin and acrylic resin, less coloring, higher light transmittance at 400 nm, and smaller YI can be obtained compared to the case of using polyimide resin alone film.

From the viewpoint of strength, the tensile elastic modulus of the film is preferably at least 3.0 GPa, more preferably at least 3.3 GPa, still more preferably at least 3.4 GPa, and may be at least 3.5 GPa, at least 3.6 GPa, or at least 3.7 GPa , above 3.8 GPa, above 3.9 GPa or above 4.0 GPa. The pencil hardness of the film is preferably F or higher, and may be H or higher or 2H or higher. In the compatible system of polyimide resin and acrylic resin, even if the ratio of acrylic resin is increased, the pencil hardness is not easy to decrease. Therefore, it is possible to provide a film with less coloring and excellent transparency without greatly reducing the mechanical strength peculiar to polyimide.

A film formed from a resin composition including a polyimide resin and an acrylic resin is suitable as a display material because of less coloring and higher transparency. In particular, films with high mechanical strength can be applied to surface components such as cover windows of displays. When the film of the present invention is actually applied, an antistatic layer, an easy-to-adhesive layer, a hard coat layer, an anti-reflection layer, etc. can be provided on the surface. [Example]

Hereinafter, an Example is shown and the embodiment of this invention is demonstrated more concretely. In addition, this invention is not limited to a following example.

[Manufacturing example of polyimide resin] Dimethylformamide was put into a separable flask, and stirred under a nitrogen atmosphere. Put diamine and acid dianhydride in the ratio (mole %) shown in Table 1 and Table 2, and stir for 5 to 10 hours under nitrogen atmosphere to react to obtain a polyamide with a solid content concentration of 18% by weight acid solution.

Add 6.0 g of pyridine as imidization catalyst to 100 g of polyamic acid solution, add 8 g of acetic anhydride after complete dispersion, and stir at 90° C. for 3 hours. After cooling to room temperature, while stirring the solution, 100 g of 2-propanol (hereinafter referred to as IPA) was added at a rate of 2 to 3 drops/second to precipitate polyimide resin. Furthermore, after adding 150 g of IPA and stirring for about 30 minutes, suction filtration was performed using a Kiriyama funnel. After the obtained solid was washed with IPA, it was dried in a vacuum oven set at 120° C. for 12 hours to obtain a polyimide resin.

[Example of film production] <Example 1> Polyimide (PI) having a composition of 6FDA/PMDA/TFMB=70/30/100 obtained in the above production example, and commercially available polymethyl methacrylate resin ("parapet HM1000" manufactured by Kuraray) , glass transition temperature: 120°C, acid value: 0.0 mmol/g, hereinafter referred to as "acrylic resin 1") was dissolved in methyl ethyl ketone (MEK) at a weight ratio of 50:50 to prepare a resin component of 11 wt. % solution. Apply the solution on an alkali-free glass plate, heat and dry at 60°C for 15 minutes in the atmosphere, heat and dry at 90°C for 15 minutes, heat and dry at 120°C for 15 minutes, heat and dry at 150°C for 15 minutes, and heat and dry at 180°C for 15 minutes. ℃ heating and drying for 15 minutes, and heating and drying at 200 ℃ for 15 minutes to produce a film with a thickness of about 50 μm.

<Examples 2-14, Comparative Examples 1-11> Change the composition of polyimide as shown in Table 1 and Table 2, use dichloromethane (DCM) or N,N-dimethylformamide (DMF) instead of methyl ethyl as shown in Table 1 and Table 2 A film was produced under the same conditions as above except that ketone (MEK) was used as a solvent.

<Examples 15-20> A film was produced on the same conditions as above except that the following acrylic resins 2 to 4 were used instead of the acrylic resin 1. Acrylic resin 2: Copolymer of methyl methacrylate/methyl acrylate (monomer ratio 87/13) ("parapet G-1000" manufactured by Kuraray, glass transition temperature 109°C, acid value 0.0 mmol/g) Acrylic resin 3: an acrylic resin having a glutarimide ring produced according to the "Manufacturing Example of Acrylic Resin" in Japanese Patent Application Laid-Open No. 2018-70710 (glutarimide content 4% by weight, glass transition temperature 125 ℃, acid value 0.4 mmol/g) Acrylic resin 4: an acrylic resin having a glutarimide ring (glutarimide content 70% by weight, glass transition temperature 146 ℃, acid value 0.1 mmol/g)

<Reference examples 1 to 4> The MEK solution of polyimide resin was prepared in Reference Example 1, the DMF solution of polyimide resin was prepared in Reference Example 3, and a film with a thickness of about 50 μm was produced under the same conditions as above. In reference examples 2 and 4, dichloromethane solutions of acrylic resins 1 and 3 were prepared, and the heating conditions during drying were changed to 60°C for 30 minutes, 80°C for 30 minutes, 100°C for 30 minutes, and 110°C for 30 minutes. Otherwise, a film having a thickness of about 50 μm was produced under the same conditions as above.

[Evaluation of Compatibility] The mixture of polyimide resin and acrylic resin shown in Tables 1 and 2 was dissolved in DMF and DCM so that the resin content was 11% by weight, and a film with a thickness of about 50 μm was produced in the same manner as in the above examples. Film, to measure the haze of the film. Those with a haze of 20% or less were judged to have compatibility (◯), and those with a haze of more than 20% were judged to have no compatibility (×). In addition, the thing which visually confirmed that the solution was clearly cloudy and the solution separated into two phases was judged as incompatibility (x) without forming a film.

[Evaluation of film] ＜Haze and total light transmittance＞ The film was cut into 3 cm squares, and the haze and total light transmittance (TT) were measured in accordance with JIS K7136 and JIS K7361-1 using a haze meter "HZ-V3" manufactured by SUGA Testing Machine. For those whose haze exceeds 20%, the following determinations of yellowness, tensile elastic modulus and pencil hardness are not carried out.

＜Transmittance at 400 nm＞ The light transmittance of the film at 300 to 800 nm was measured using an ultraviolet-visible spectrophotometer "V-770" manufactured by JASCO Corporation, and the light transmittance at a wavelength of 400 nm was read.

＜Yellowness＞ The film was cut into 3 cm squares, and the yellowness (YI) was measured in accordance with JIS K7373 using a spectrophotometer "SC-P" manufactured by SUGA Testing Instruments.

＜Modulus of elasticity in tension＞ Cut the film into short strips with a width of 10 mm, let it stand at 23°C/55%RH (Relative Humidity, relative humidity) for 1 day to control the humidity, and use "AUTOGRAPH AGS-X" manufactured by Shimadzu Corporation, in the following The tensile modulus of elasticity was measured under the conditions. Distance between fixtures: 100 mm Tensile speed: 20.0 mm/min Measuring temperature: 23°C

＜Pencil hardness＞ The pencil hardness of the film was measured according to JIS K5600-5-4 "pencil scratch test".

＜Bending Resistance＞ Cut the film into short strips of 20 mm×100 mm, bend it 180° at the center of the length direction, and mark "○" if the film is not broken, and mark "×" if the film is broken.

[evaluation result] Table 1 and Table 2 show the resin composition (composition of polyimide, type of acrylic resin, and mixing ratio) and evaluation results of the film.

In Table 1 and Table 2, the compounds are described by the following abbreviations. ＜Acid dianhydride＞ 6FDA: 4,4'-(hexafluoroisopropylidene)diphthalic anhydride PMDA: pyromellitic dianhydride MPDA: 1,2,3,5-Benzenetetracarboxylic dianhydride BPDA: 3,3',4,4'-Biphenyltetracarboxylic dianhydride BPADA: 4,4'-(4,4'-isopropylidenediphenoxy)diphthalic anhydride BTDA: 3,3',4,4'-Benzophenone tetracarboxylic dianhydride ODPA: 4,4'-oxydiphthalic anhydride BPAF: 9,9-bis(3,4-dicarboxyphenyl) fenneldianhydride TAHQ: Terephthalic bis(trimellitic anhydride) TAHMBP: bis(1,3-dihydroisobenzofuran-5-carboxylic acid)-2,2',3,3',5,5'-hexamethylbiphenyl- 4,4'-diyl ＜Diamine＞ TFMB: 2,2'-bis(trifluoromethyl)benzidine DDS: 3,3'-Diaminodiphenylsulfone ODA: 3,4'-diaminodiphenyl ether m-PDA: m-phenylenediamine BAPP: 2,2'-bis[4-(4-aminophenoxy)phenyl]propane HFBAPP: 2,2'-bis[4-(4-aminophenoxy)phenyl]hexafluoropropane

[Table 1] Resin composition Compatibility solvent Membrane properties Composition of polyimide (mol%) Types of acrylic resin PI/acrylic acid (weight ratio) DMF DCM Thickness (μm) Haze (%) TT (%) 400 nm transmittance (%) YI Tensile modulus of elasticity (GPa) pencil hardness Bending resistance Acid dianhydride diamine 6FDA other 1 other 2 TFMB other type quantity type quantity type quantity Example 1 70 PMDA 30 - 100 - 1 50/50 ○ x MEK 51 0.3 91.5 68.4 1.6 4.0 3H ○ Reference example 1 70 PMDA 30 - 100 - - 100/0 MEK 46 0.5 90.2 34.2 5.2 4.0 3H ○ Reference example 2 - 1 0/100 DCM 60 0.3 92.5 92.1 0.2 2.6 HB x Example 2 40 PMDA 30 BPADA 30 100 - 1 50/50 ○ ○ DCM 52 0.3 91.1 63.7 1.8 3.6 3H ○ Example 3 40 PMDA 40 BPADA 20 100 - 1 50/50 ○ ○ DCM 45 0.3 91.1 61.0 2.1 4.0 3H ○ Example 4 40 PMDA 40 BPADA 20 80 DDS 20 1 50/50 ○ ○ DMF 53 0.3 91.1 61.6 2.3 3.2 h ○ Example 5 70 MPDA 30 - 100 - 1 50/50 ○ ○ DCM 55 0.2 91.6 67.6 1.6 3.3 3H ○ Example 6 50 MPDA 50 - 100 - 1 50/50 ○ ○ DCM 55 0.3 91.4 52.8 2.6 3.3 3H ○ Example 7 70 TAHMBP 30 - 100 - 1 50/50 ○ x DMF 56 0.3 90.7 85.0 1.4 3.4 3H ○ Example 8 70 BTDA 30 - 100 - 1 50/50 ○ x DMF 59 0.2 91.4 71.1 2.0 3.4 2H ○ Example 9 70 ODPA 30 - 100 - 1 50/50 ○ x DMF 54 0.2 91.5 87.6 0.7 3.4 3H ○ Example 10 60 BPAF 40 - 100 - 1 50/50 ○ x DMF 64 0.2 91.3 86.2 0.8 3.4 2H ○ Example 11 40 BPDA 30 ODPA 30 100 - 1 50/50 ○ x DMF 56 0.3 91.3 85.5 0.8 3.4 2H ○ Example 12 50 BPDA 25 TAHQ 25 70 DDS 30 1 50/50 ○ x DMF 48 0.2 91.2 79.6 1.0 3.6 2H ○ Example 13 55 BPDA 45 - 100 - 1 50/50 ○ x DMF 54 0.3 91.3 77.3 0.9 3.6 2H ○ Example 14 60 BPDA 40 - 100 - 1 50/50 ○ x DMF 56 0.3 91.3 78.7 1.0 3.5 3H ○ Example 15 60 BPDA 40 - 100 - 2 50/50 ○ x DMF 50 0.2 91.3 80.0 1.0 3.4 2H ○ Example 16 60 BPDA 40 - 100 - 3 50/50 ○ x DMF 50 0.3 91.3 79.2 1.0 3.5 2H ○ Example 17 60 BPDA 40 - 100 - 3 70/30 ○ x DMF 55 0.3 90.7 69.2 1.4 3.6 2H ○ Reference example 3 60 BPDA 40 - 100 - - 100/0 DMF 49 0.2 89.9 52.3 1.9 3.6 2H ○ Reference example 4 - 3 0/100 DCM 51 0.2 92.5 92.1 0.2 2.6 HB x Example 18 40 PMDA 30 BPADA 30 100 - 4 50/50 ○ ○ DCM 50 0.3 90.8 62.0 1.9 3.7 2H ○ Example 19 40 PMDA 40 BPADA 20 100 - 4 50/50 ○ ○ DCM 53 0.2 90.8 52.5 2.6 3.8 3H ○ Example 20 60 BPDA 40 - 100 - 4 50/50 ○ x DMF 57 1.3 90.8 52.1 1.4 3.7 2H ○

[Table 2] Resin composition Compatibility solvent Membrane properties Composition of polyimide (mol%) Types of acrylic resin PI/acrylic acid (weight ratio) DMF DCM Thickness (μm) Haze (%) TT (%) 400nm transmittance (%) YI Tensile modulus of elasticity (GPa) pencil hardness Bending resistance Acid dianhydride diamine 6FDA other 1 other 2 TFMB other type quantity type quantity type quantity Comparative example 1 100 - 100 - 1 50/50 ○ x DMF 52 0.3 91.7 87.6 0.7 3.3 h ○ Comparative example 2 DCM 51 56.0 x Comparative example 3 100 - 30 DDS 70 1 50/50 ○ x DMF 55 0.6 90.0 87.6 0.8 3.1 f ○ Comparative example 4 100 - - DDS 100 1 50/50 x x DMF 66 93.8 x Comparative Example 5 100 - - BAPP 100 1 50/50 x x DMF 66 93.3 x Comparative example 6 100 - - HFBAPP 100 1 50/50 ○ x DMF 52 0.3 91.4 52.1 3.3 2.9 f ○ Comparative Example 7 100 - - m-PDA 100 1 50/50 ○ x DMF 50 0.3 90.9 79.8 1.1 2.9 2H ○ Comparative Example 8 100 - - ODA 100 1 50/50 ○ x DMF 50 0.3 88.5 43.6 8.1 2.9 HB ○ Comparative Example 9 30 BPADA 70 - 100 - 1 50/50 ○ x DMF 60 0.3 91.2 83.8 0.8 3.0 f ○ Comparative Example 10 60 BPDA 40 - 30 DDS 70 1 50/50 x x DMF 58 94.8 x Comparative Example 11 - TAHMBP 100 - - DDS 100 1 50/50 x x DMF 44 90.0 x

The polyimide film of Reference Example 1 produced using only polyimide resin had a high tensile elastic modulus and excellent mechanical properties, but its YI exceeded 2 and its transparency was insufficient. The acrylic film of Reference Example 2 prepared using only acrylic resin 1 had a low tensile elastic modulus, a pencil hardness of HB, and insufficient mechanical strength. In addition, the bending resistance of the acrylic film of Reference Example 2 was not sufficient.

Compared with the polyimide film of Reference Example 1, the total light transmittance and wavelength of 400 nm of the film of Example 1 using a resin composition mixed with the same polyimide resin and acrylic resin 1 as in Reference Example 1 The transmittance is higher, the YI becomes smaller, the coloring is less, and the transparency is improved. Also, the film of Example 1 has higher mechanical strength than the acrylic film of Reference Example 2, and has the same tensile modulus and pencil hardness as the polyimide film of Reference Example 1.

In Examples 2 to 14 using a polyimide resin different from that of Example 1, the haze of the film was smaller and the YI was smaller than that of the acrylic film of Reference Example 2 as in Example 1. , the mechanical strength is improved. The films of Example 15 and Example 16, which are equivalent to changing the acrylic resin of Example 14, also have excellent mechanical strength and transparency, and are equivalent to changing the polyimide resin and acrylic resin in Example 16. The same is true for Example 17 obtained from the ratio. The films of Examples 18 to 20 using the acrylic resin 4 having a higher glutaryl imidization ratio than the acrylic resin 3 also had excellent mechanical strength and transparency.

From the comparison of the polyimide film of reference example 3 and the acrylic film of reference example 4 and the film of embodiment 17, it can be known that, like the comparison between reference examples 1 and 2 and embodiment 1, polyimide resin and polyimide resin are mixed. The resin film of the acrylic resin has excellent mechanical strength compared with the case of the acrylic resin alone, and has improved transparency compared with the case of the polyimide alone.

From the comparison of Reference Example 3, Example 17, Example 16, and Reference Example 4, it can be seen that as the ratio of acrylic resin increases, YI decreases linearly and transmittance increases linearly. That is, it turns out that the transparency of a film improves by increasing the ratio of an acrylic resin. On the other hand, regarding the mechanical strength, as the ratio of acrylic resin increases, the tensile elastic modulus tends to decrease. Reference Example 3 without acrylic resin and Example 17 with a ratio of acrylic resin of 30% The tensile modulus of elasticity is the same. From these results, it was found that when the ratio of the acrylic resin is low, the transparency can be improved without lowering the mechanical strength of the film almost.

The film of Comparative Example 1 using a polyimide resin containing only 6FDA, which is a fluorine-containing aromatic tetracarboxylic dianhydride as tetracarboxylic dianhydride, and not containing fluorine-free aromatic tetracarboxylic dianhydride was transparent. Excellent mechanical properties, but the tensile elastic modulus was 3.3 GPa, and compared with the films of Example 1 and others, the mechanical strength was lower. In Comparative Example 2 in which the same resin composition as Comparative Example 1 was dissolved in methylene chloride to form a film, the polyimide resin and the acrylic resin did not show compatibility, and the haze increased significantly.

Regarding the compositions of Comparative Examples 4 and 5 obtained by changing the type of diamine of the polyimide of Comparative Example 1, the polyimide resin and the acrylic resin did not show compatibility in DMF. The same applies to Comparative Examples 10 and 11.

Compared with Comparative Example 1, Comparative Examples 3, 6-8 obtained by changing the type of diamine of polyimide in Comparative Example 1 had lower mechanical strength. In addition, the YI of the films of Comparative Examples 6 and 8 was large, and the transparency was not sufficient. The film of Comparative Example 9 in which the ratio of the fluorine-containing aromatic tetracarboxylic dianhydride (6FDA) was small was lower in mechanical strength than in Examples 10 and 11.

Furthermore, although the tensile elastic modulus of the films of Examples 4-6 is the same as that of Comparative Example 1, they have the following advantages: the compatibility between polyimide resin and acrylic resin is relatively high, and it is better than non-amide such as dichloromethane. It also exhibits excellent compatibility in solvents, and can obtain films with high transparency. The compositions of Examples 2, 3, 18, and 19 showed compatibility in dichloromethane and had excellent mechanical strength. The composition of Example 1 did not show compatibility in methylene chloride, but showed compatibility in methyl ethyl ketone which is a non-amide solvent.

In embodiments 1 to 6 and embodiments 18 and 19, it is believed that PMDA and MPDA are non-fluorine-containing tetracarboxylic dianhydrides that are bonded with two acid anhydride groups in one benzene ring to help improve the polyimide resin and Compatibility of acrylic resins. Moreover, in Examples 2-4, 18, and 19, it is thought that BPADA also contributes to improvement of compatibility.

From the above results, it can be seen that a specific amount of fluorine-containing aromatic tetracarboxylic dianhydride and fluorine-free aromatic tetracarboxylic dianhydride are contained as tetracarboxylic dianhydride components, and fluoroalkyl-substituted benzidine is contained as diamine Polyimide, which is a component, exhibits compatibility with acrylic resins, and by using a resin composition mixed with these, a film with high transparency and excellent mechanical strength can be obtained.

Claims (10)

A resin composition comprising polyimide and acrylic resin, The above-mentioned polyimide contains fluorine-containing aromatic tetracarboxylic dianhydride and fluorine-free aromatic tetracarboxylic dianhydride as a tetracarboxylic dianhydride component, and contains fluoroalkyl-substituted benzidine as a diamine component, The amount of fluorine-containing aromatic tetracarboxylic dianhydride is 30-90 mole % relative to the total amount of tetracarboxylic dianhydride components in the above-mentioned polyimide, and the amount of fluorine-free aromatic tetracarboxylic dianhydride 10-70 mol%, The amount of fluoroalkyl-substituted benzidine is 25 mol% or more relative to the total amount of diamine components in the polyimide. The resin composition as claimed in item 1, wherein the above-mentioned fluorine-free tetracarboxylic dianhydride comprises pyromellitic dianhydride, 1,2,3,5-pyromellitic dianhydride, 3,3',4 ,4'-Biphenyltetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 4,4'- (4,4'-Isopropylidenediphenoxy)diphthalic anhydride, 9,9-bis(3,4-dicarboxyphenyl)stilamide, and bis(trimellitic anhydride) ester One or more of the groups formed. The resin composition according to claim 1 or 2, wherein the above-mentioned fluorine-containing aromatic tetracarboxylic dianhydride is 4,4'-(hexafluoroisopropylidene) diphthalic anhydride. 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 in the acrylic resin, the total amount of methyl methacrylate and the modified structure of methyl methacrylate is 60% by weight or more relative to the total amount of monomer components. The resin composition according to claim 1 or 2, wherein the glass transition temperature of the acrylic resin is above 90°C. The resin composition according to claim 1 or 2, comprising the above-mentioned polyimide and the above-mentioned acrylic resin in a weight ratio in the range of 98:2 to 2:98. A molded body comprising the resin composition according to any one of claims 1 to 7. A film comprising the resin composition according to any one of claims 1 to 7. For the film of claim 9, its thickness is not less than 5 μm and not more than 300 μm, the total light transmittance is not less than 85%, the haze is not more than 10%, the yellowness is not more than 3.0, and the tensile elastic modulus is not less than 3.0 GPa, pencil The hardness is F or higher.