阅读说明：本技术 聚酰胺酸组合物、聚酰亚胺组合物及聚酰亚胺成型体 (Polyamic acid composition, polyimide composition, and polyimide molded article ) 是由 宫本刚 于 2020-03-26 设计创作，主要内容包括：本发明的聚酰胺酸组合物由包含下述通式(A)所表示的重复单元的聚酰胺酸溶解或分散于溶剂中而形成,通式(A)中：R～(A)及R～(B)各自独立地为氢原子或甲基；R～(C)为氢原子、碳原子数为1～20的烷基或碳原子数为2～10的烯基；B～(A)为二价有机基团；B～(3)及B～(4)各自独立地为-C(＝O)-或-CH-(2)-；G～(1)及G～(2)各自独立地包含选自由脂肪族环及芳香族环组成的组中的至少一种环、或各自独立地为直链状的碳原子数为4～10的烷三基,当环为两个以上时,环为稠环。(The polyamic acid composition of the present invention is formed by dissolving or dispersing a polyamic acid containing a repeating unit represented by the following general formula (A) in a solvent, in the general formula (A): r A And R B Each independently is a hydrogen atom or a methyl group; r C Is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms; b is A Is a divalent organic group; b is 3 And B 4 Each independently is-C (═ O) -or-CH 2 ‑；G 1 And G 2 Each independently contains at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, or each independently is a straight ringAnd a chain alkanetriyl group having 4 to 10 carbon atoms, wherein when the number of rings is two or more, the rings are fused rings.)

1. A polyamic acid composition formed by dissolving or dispersing in a solvent a polyamic acid containing a repeating unit represented by the following general formula (A),

[ chemical formula 1]

In the general formula (A):

R^Aand R^BEach independently is a hydrogen atom or a methyl group;

R^Cis a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B^Ais a divalent organic group;

B³and B⁴Each independently is-C (═ O) -or-CH₂-；

G¹And G²Each independently includes at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, or a linear alkanetriyl group having 4 to 10 carbon atoms, and when the number of the rings is two or more, the rings are fused rings.

2. The polyamic acid composition according to claim 1, wherein,

in the general formula (A): g¹And G²Each independently comprises at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring.

3. The polyamic acid composition according to claim 1 or 2, wherein,

the repeating unit represented by the general formula (A) includes at least one repeating unit selected from the group consisting of the following general formula (I), the following general formula (II), the following general formula (III), and the following general formula (IV),

[ chemical formula 2]

In the general formula (I):

R¹and R²Each independently is a hydrogen atom or a methyl group;

R³is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B¹is a divalent organic group, and is a divalent organic group,

[ chemical formula 3]

In the general formula (II):

R¹¹and R¹²Each independently is a hydrogen atom or a methyl group;

R¹³is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms; b is¹¹Is a divalent organic group, and is a divalent organic group,

[ chemical formula 4]

In the general formula (III):

R²¹and R²²Each independently is a hydrogen atom or a methyl group;

R²³is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B²¹is a divalent organic group, and is a divalent organic group,

[ chemical formula 5]

In the general formula (IV):

R³¹and R³²Each independently is a hydrogen atom or a methyl group;

R³³is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B³¹is a divalent organic group.

4. The polyamic acid composition according to any one of claims 1 to 3, wherein,

the polyamic acid containing the repeating unit represented by the general formula (a) does not contain a dicarboxylic acid structure derived from a tetracarboxylic acid at the molecular end.

5. The polyamic acid composition according to any one of claims 1 to 4, wherein,

The polyamic acid containing the repeating unit represented by the general formula (A) has an amino group derived from a diamine at the molecular end,

amino group (-NH) in the polyamic acid₂) The ratio of (B) is in the range of 0.001 to 0.1 mol/kg.

6. A polyimide molded body produced by: coating the polyamic acid composition according to any one of claims 1 to 5 on a substrate, and heating the composition to effect distillation removal of the solvent and imidization.

7. A polyimide composition which is formed by dissolving or dispersing a polyamide acid containing a repeating unit represented by the following general formula (B) in a solvent,

[ chemical formula 6]

In the general formula (B):

R^Dand R^EEach independently is a hydrogen atom or a methyl group;

R^Fis a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B^Dis a divalent organic group;

B⁵and B⁶Each independently is-C (═ O) -or-CH₂-；

G³And G⁴Each independently includes at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, or a linear alkanetriyl group having 4 to 10 carbon atoms, and when the number of the rings is two or more, the rings are fused rings.

8. The polyimide composition according to claim 7,

In the general formula (B): g³And G⁴Each independently comprises at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring.

9. The polyimide composition according to claim 7 or 8,

the repeating unit represented by the general formula (B) includes at least one repeating unit selected from the group consisting of the following general formula (V), the following general formula (VI), the following general formula (VII), and the following general formula (VIII),

[ chemical formula 7]

In the general formula (V):

R⁴and R⁵Each independently is a hydrogen atom or a methyl group;

R⁶is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms；

B²Is a divalent organic group, and is a divalent organic group,

[ chemical formula 8]

In the general formula (VI):

R¹⁴and R¹⁵Each independently is a hydrogen atom or a methyl group;

R¹⁶is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms; b is¹²Is a divalent organic group, and is a divalent organic group,

[ chemical formula 9]

In the general formula (VII):

R²⁴and R²⁵Each independently is a hydrogen atom or a methyl group;

R²⁶is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B²²is a divalent organic group, and is a divalent organic group,

[ chemical formula 10]

In the general formula (VIII):

R³⁴and R³⁵Each independently is a hydrogen atom or a methyl group;

R³⁶is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B³²Is a divalent organic group.

10. The polyimide composition according to any one of claims 7 to 9,

the polyimide containing the repeating unit represented by the general formula (B) does not contain a dicarboxylic acid structure derived from a tetracarboxylic acid at the molecular terminal.

11. The polyimide composition according to any one of claims 7 to 10,

an amino group derived from a diamine is contained at the molecular terminal of a polyimide comprising a repeating unit represented by the general formula (B),

amino (-NH) groups in the polyimide₂) The ratio of (B) is in the range of 0.001 to 0.1 mol/kg.

12. A polyimide molded article produced by:

coating a substrate with the polyimide composition according to any one of claims 7 to 11, and heating the coated substrate to remove the solvent by distillation.

Technical Field

The present invention relates to a polymer compound having transparency and ultraviolet durability.

The present invention relates to a polyimide molded article having excellent heat resistance, and more particularly to a transparent polyimide film which can be suitably used as a material (for example, a glass substitute for a display device) for forming a product or a device which is required to have high heat resistance, transparency, and ultraviolet durability. The present invention also relates to a polyamic acid composition and a polyimide composition for producing the polyimide molded article.

Background

Polyimide obtained by polycondensation of tetracarboxylic dianhydride and diamine compound has been known as a polymer having excellent heat resistance, physical properties and chemical resistance and also having a low dielectric constant. From the above properties, polyimide is used for various applications, and is widely used as a protective material, an insulating material, and the like, particularly in the field of electric and electronic materials (patent document 1).

However, conventional wholly aromatic polyimides composed of an aromatic tetracarboxylic dianhydride and a diamine compound are often colored in yellow or brown, although they are excellent in mechanical properties and durability, and cannot be used for display substrates and the like requiring transparency.

As a polyimide having transparency, for example, a polyimide having a repeating unit derived from an aliphatic monomer, a fluorine-containing monomer, or a monomer having a bulky substituent on a side chain of a molecule has been proposed (patent document 2). However, although the polyimide containing a repeating unit derived from these monomers has improved transparency, mechanical strength and durability may be significantly reduced.

Therefore, a polyimide which is excellent in transparency and also excellent in mechanical strength and durability as a substrate for a display, for example, has been demanded. That is, polyimides are required to have characteristics (excellent transparency, mechanical strength and durability) which are opposite to each other. In addition, a polyamic acid composition and a polyimide composition for preparing the polyimide are also needed.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2007-152932

Patent document 2: japanese patent laid-open publication No. 2004-111152

Disclosure of Invention

Technical problem to be solved by the invention

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a polyimide molded body (for example, a transparent polyimide film) having excellent transparency, mechanical strength, and durability at the same time. Another object of the present invention is to provide a polyamic acid composition and a polyimide composition for producing the polyimide molded product.

Means for solving the problems

The present inventors have intensively studied to solve the above-mentioned problems, and paid attention to the fact that specific portions (for example, a color developing group (aromatic ring or the like) having a specific light absorption band) of a polyimide molded product are in close proximity to each other to form intermolecular and intramolecular Charge Transfer (CT) complexes, thereby lowering transparency. Based on this point, a method for widening the molecular chains in a polyamic acid composition and a polyimide composition for producing a polyimide molded body at a predetermined distance to suppress the formation of a CT complex has been found.

On the other hand, the inventors focused on the phenomenon that in a polyimide molded body containing a repeating unit from a monomer having a bulky group in a molecular side chain, the bulky group functions as a spacer, whereby the distance between molecular chains becomes wide and the ordered arrangement of the molecular chains is disturbed, resulting in a decrease in mechanical strength and durability. In view of the above, it has been found that the molecular chains in the polyamic acid composition and the polyimide composition for producing a polyimide molded article are shortened by a predetermined distance so as to maintain the ordered molecular chain arrangement to some extent.

As a result of further studies by the present inventors, the present invention has been achieved, which is to provide transparency and mechanical strength and durability by introducing a steroid structure which functions as a spacer between molecular chains and is lipophilic and cohesive into the main chain of the repeating unit of polyamic acid and polyimide. That is, the present invention includes the following embodiments.

The polyamic acid composition according to an embodiment of the present invention is formed by dissolving or dispersing a polyamic acid including a repeating unit represented by the following general formula (a) in a solvent.

[ chemical formula 1]

In the general formula (A):

R^Aand R^BEach independently is a hydrogen atom or a methyl group;

R^Cis a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B^Ais a divalent organic group;

B³and B⁴Each independently is-C (═ O) -or-CH₂-；

G¹And G²Each independently includes at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, or an alkanetriyl group (alkyl group) having 4 to 10 carbon atoms and being linear, and when the number of rings is two or more, the rings are fused rings.

A polyimide molded article according to another embodiment of the present invention is produced by applying the above polyamic acid composition to a substrate, and heating the composition to distill off the solvent and perform imidization.

The polyimide composition according to another embodiment of the present invention is formed by dissolving or dispersing a polyimide containing a repeating unit represented by the following general formula (B) in a solvent,

[ chemical formula 2]

In the general formula (B):

R^Dand R^EEach independently is a hydrogen atom or a methyl group;

R^Fis a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B^Dis a divalent organic group;

B⁵and B⁶Each independently is-C (═ O) -or-CH₂-；

G³And G⁴Each independently contains at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, or a linear alkanetriyl group having 4 to 10 carbon atoms, and when the number of rings is two or more, the rings are fused rings.

A polyimide molded product according to another embodiment of the present invention is produced by applying the polyimide composition to a substrate and heating to distill off the solvent.

Effects of the invention

According to the present invention, a polyimide molded body having excellent transparency, mechanical strength and durability can be provided. Further, a polyamic acid composition and a polyimide composition for producing the polyimide molded article can be provided.

Detailed Description

Embodiments of the present invention (polyamic acid composition, polyimide composition, and polyimide molded product) will be described in detail below. However, the present invention is not limited to the following embodiments, and the present invention can be additionally modified as appropriate within the scope of the object of the present invention. Note that, where the description is repeated, the description may be appropriately omitted, but the invention is not limited thereto.

< definition >

The following are each, unless otherwise specified, an alkyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 10 carbon atoms, an alkyl group having 1 to 3 carbon atoms, an alkenyl group having 2 to 10 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, a haloalkyl group having 1 to 3 carbon atoms, a halogen atom, an alkylene group having 1 to 3 carbon atoms, a cycloalkane diyl group having 5 to 7 carbon atoms, an arylene group, a cycloalkane ring having 5 to 7 carbon atoms, a straight-chain alkanetriyl group having 4 to 10 carbon atoms, a straight-chain alkanetriyl group having 4 to 6 carbon atoms, and an alcohol having 4 or less carbon atoms.

The alkyl group having 1 to 20 carbon atoms is linear or branched and is unsubstituted. Examples of the alkyl group having 1 to 20 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl and-CH (CH)₃)(CH₂)₃CH(CH₃)₂N-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, n-nonadecyl and n-eicosyl.

The alkyl group having 1 to 10 carbon atoms is linear or branched and is unsubstituted. Examples of the alkyl group having 1 to 10 carbon atoms include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, n-hexyl, n-heptyl, n-octyl and-CH (CH)₃)(CH₂)₃CH(CH₃)₂N-nonyl and n-decyl.

The alkyl group having 1 to 3 carbon atoms is linear or branched and is unsubstituted. Examples of the alkyl group having 1 to 3 carbon atoms include a methyl group, an ethyl group, an n-propyl group and an isopropyl group.

The alkenyl group having 2 to 10 carbon atoms is linear or branched and is unsubstituted. Examples of the alkenyl group having 2 to 10 carbon atoms include an ethenyl group, a propenyl group, a butenyl group and a-CH (CH) ₃)(CH₂)₂CH＝C(CH₃)₂。

The alkoxy group having 1 to 3 carbon atoms is linear or branched and unsubstituted, and examples of the alkoxy group having 1 to 3 carbon atoms include a methoxy group, an ethoxy group, an n-propoxy group and an isopropoxy group.

The haloalkyl group having 1 to 3 carbon atoms is linear or branched and is unsubstituted. The haloalkyl group having 1 to 3 carbon atoms is a group in which one or more hydrogen atoms in the alkyl group having 1 to 3 carbon atoms are substituted with one or more halogen atoms, and examples thereof include a trifluoromethyl group.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom and an iodine atom.

The alkylene group having 1 to 3 carbon atoms is linear or branched and is unsubstituted. Examples of the alkylene group having 1 to 3 carbon atoms include a methylene group, an ethylene group, an n-propylene group and an isopropylene group.

The cycloalkylene group having 5 to 7 carbon atoms (cycloalkyldiyl) is cyclic and unsubstituted. Examples of the cycloalkylene group having 5 to 7 carbon atoms include cyclopentanediyl, cyclohexanediyl, and cycloheptanediyl (more specifically, 1, 4-cyclohexanediyl, 1, 3-cyclohexanediyl, and the like).

Arylene (aryl diyl group) is cyclic and unsubstituted. Examples of the arylene group include monocyclic or polycyclic arylene groups having 6 to 14 carbon atoms. Examples of the monocyclic arylene group having 6 to 14 carbon atoms include a phenylene group (more specifically, a p-phenylene group and the like). Examples of the polycyclic arylene group include bicyclic arylene groups (more specifically, naphthylene (naphthalenediyl) and indenediyl groups), tricyclic arylene groups (more specifically, anthracenediyl, phenanthrenediyl, acenaphthenediyl and indacene (indacene) diyl groups).

The cycloalkane ring having 5 to 7 carbon atoms is cyclic and unsubstituted. Examples of the cycloalkane ring having 5 to 7 carbon atoms include a cyclopentane ring, a cyclohexane ring, and a cycloheptane ring.

The straight chain alkanetriyl group having 4 to 10 carbon atoms is unsubstituted. Examples of the linear alkanetriyl group having 4 to 10 carbon atoms include n-butanetriyl group, n-pentanetriyl group, n-hexanetriyl group, n-heptanetriyl group, n-octanetriyl group, n-nonanetriyl group and n-decanetriyl group.

The straight chain alkanetriyl group having 4 to 6 carbon atoms is unsubstituted. Examples of the linear alkanetriyl group having 4 to 6 carbon atoms include n-butanetriyl group, n-pentanediyl group, and n-hexanetriyl group.

The alcohol having 4 or less carbon atoms is linear or branched and is unsubstituted. The alcohol having 4 or less carbon atoms is an alcohol having 1 to 4 carbon atoms. Examples of the alcohol having 1 to 4 carbon atoms include methanol, ethanol, n-propanol and isopropanol.

< first embodiment: polyamic acid composition

[ Polyamic acid ]

The polyamic acid composition of the first embodiment of the invention comprises polyamic acid and a solvent. The polyamic acid composition (hereinafter, sometimes referred to as "polyamic acid composition (a)") is formed by dissolving or dispersing a polyamic acid (hereinafter, sometimes referred to as "polyamic acid (a)") containing a repeating unit represented by the following general formula (a) (hereinafter, sometimes referred to as "repeating unit (a)") in a solvent.

[ chemical formula 3]

In the general formula (A):

R^Aand R^BEach independently is a hydrogen atom or a methyl group;

R^Cis a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B^Ais a divalent organic group;

B³and B⁴Each independently is-C (═ O) -or-CH₂-；

G¹And G²Each independently contains at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, or a linear alkanetriyl group having 4 to 10 carbon atoms, and when the number of rings is two or more, the rings are fused rings.

In the general formula (A), R^AAnd R^BPreferably methyl.

R^CPreferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂Further preferred is-CH (CH)₃)(CH₂)₃CH(CH₃)₂。

B^AThe divalent organic group preferably contains at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, and more preferably a divalent organic group represented by the general formula (a-1).

-B^A1-(Y¹-B^A1)_n1-···(A-1)

In the general formula (A-1):

B^A1a group that is an arylene group or a divalent aliphatic ring;

Y¹a heteroatom selected from the group consisting of a single bond, an oxygen atom and a sulfur atom, a carbonyl group (-C (═ O) -), or a sulfonyl group (-S (═ O)₂-)；

n1 is an integer of 0-2;

when n1 is an integer of 1 or more, a plurality of B^A1May be the same as or different from each other;

when n1 is an integer of 2 or more, plural Y' s ¹May be the same as each other or different from each other.

Examples of the divalent aliphatic ring group include monocyclic or polycyclic divalent aliphatic ring groups. Examples of the monocyclic divalent aliphatic ring group include a cycloalkylene group having 5 to 7 carbon atoms. Examples of the polycyclic divalent aliphatic ring group include a bicyclic divalent aliphatic ring group and a tricyclic or higher divalent aliphatic ring group. Examples of the group of the bicyclic divalent aliphatic ring include a divalent group formed by condensation of two monocyclic aliphatic rings (more specifically, bicyclic [4.4.0 ] ring]Decanediyl (decahydronaphthalenediyl), bicyclo [2.2.1]Heptanediyl (norbornanediyl) and the like) and a divalent group (more specifically, a tricyclo [5.2.1.0 ] group formed by condensation of three monocyclic aliphatic rings^2,6]Decanediyl, etc.).

When n1 represents an integer of 1 or more and X represents a single bond, two of B bonded via the single bond^AIn (3), other ring-forming atoms than the ring-forming atom forming a single bond may be directly bonded to each other or may be bonded to each otherIs indirectly bonded through an alkylene group having 1 to 3 carbon atoms. At this time, B^A1Examples are biphenylenediyl and fluorenediyl.

B^A1The arylene or divalent alicyclic ring group represented can further have one or more substituents. Examples of the substituent include an alkyl group having 1 to 3 carbon atoms, a haloalkyl group having 1 to 3 carbon atoms, and an alkoxy group having 1 to 3 carbon atoms. Among these substituents, methyl is preferred.

B³And B⁴May be the same as each other or different from each other.

G¹And G²The straight chain alkanetriyl group having 4 to 10 carbon atoms is preferably a straight chain alkanetriyl group having 4 to 6 carbon atoms. The straight chain alkanetriyl group having 4 to 10 carbon atoms is a trivalent substituent. Among 4 to 10 carbon atoms of a straight chain alkanetriyl group having 4 to 10 carbon atoms, a carbon atom bonded to a carboxyl group and a carbon atom bonded to a carbonyl group are directly bonded by a single bond.

As G¹And G²Examples of the alicyclic ring include monocyclic or polycyclic aliphatic rings. Examples of the monocyclic aliphatic ring include a cycloalkane ring having 5 to 7 carbon atoms. Examples of the polycyclic aliphatic ring include a ring formed by condensation of two monocyclic aliphatic rings (more specifically, bicyclo [4.4.0 ]]Decane ring and bicyclo [2.2.1]Heptane ring, etc.) and three monocyclic aliphatic rings (more specifically, a tricyclic ring [5.2.1.0 ]^2,6]Decane ring, etc.).

As G¹And G²Examples of the aromatic ring include a ring having 6 to 14 carbon atoms or a polycyclic aromatic ring. Examples of the monocyclic aromatic ring having 6 to 14 carbon atoms include a benzene ring. Examples of the polycyclic aromatic ring having 6 to 14 carbon atoms include a bicyclic naphthalene ring, and a tricyclic anthracene ring, phenanthrene ring, and acenaphthene ring.

G¹And G²Preferably each independently contains at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, and more preferably is a single ringA cycloaliphatic ring or a monocyclic aromatic ring, and more preferably a cyclohexane ring or a benzene ring. In addition, G¹And G²May be the same as each other or different from each other.

B^A1Preferably a monocyclic arylene group having 6 to 14 carbon atoms or a cycloalkylene group having 5 to 7 carbon atoms, more preferably a phenylene group or a cyclohexanediyl group, still more preferably a p-phenylene group or a 1, 4-cyclohexanediyl group, and particularly preferably a p-phenylene group.

n1 is preferably 0 or 1.

Y¹Preferably a single bond, an alkylene group having 1 to 3 carbon atoms, or a hetero atom such as an oxygen atom and a sulfur atom, more preferably a single bond, a methylene group, or an oxygen atom, and still more preferably a single bond or an oxygen atom.

The polyamic acid in the polyamic acid composition according to the first embodiment includes the repeating unit (a), and thus can have excellent transparency, mechanical strength, and durability at the same time. The reason for this is considered as follows.

The repeating unit (A) has a steroid structure derived from a steroid diol represented by the following general formula (C). The steroid structure has a structure in which four aliphatic rings are Trans-condensed (Trans condensation) in a chair-like conformation. The repeating unit (a) has a bulky steroid structure in the main chain, and thus can function as a spacer between polyamic acids in which linear molecular chains are arranged in parallel. Therefore, the repeating unit (a) can widen the inter-molecular chain distance and maintain a predetermined distance, and can disturb the ordered arrangement of the molecular chains to some extent. It is considered that the overlapping of specific portions (for example, coloring groups (aromatic rings, etc.) having specific light absorption bands) on the molecular chain of the polyamic acid with each other is thus suppressed. Therefore, it is difficult to form an intermolecular or intramolecular Charge Transfer (CT) complex having a light absorption band in the visible light region. The steroid structure is a condensed ring of an aliphatic ring, a condensed ring having no aromatic ring such as fluorene, or a polycyclic structure in which aromatic rings such as bisphenol a are connected via a carbon or oxygen atom. Therefore, the steroid structure does not form an intramolecular CT complex such as an aromatic ring, and the polyamic acid composition of the first embodiment is excellent in transparency.

On the other hand, the steroid structure is bulky, and in the repeating unit (a), it is lipophilic compared to the amide bond and the carboxyl group. Therefore, the steroid moiety has cohesiveness, and the steroid structures between different molecular chains attract each other, so that the distance between the molecular chains of the polyamic acid can be shortened by a predetermined distance and maintained. Thus, the molecular chains of the polyamic acid can be arranged in order to some extent, and thus the polyamic acid composition of the first embodiment is excellent in mechanical strength and durability.

Thus, the polyamic acid according to the first embodiment can maintain an appropriate distance between the molecular chains of the polyamic acid by the steroid structure, and thus can have transparency, mechanical strength, and durability which are characteristics opposite to each other.

The repeating unit (a) preferably includes at least one of repeating units selected from the group consisting of the following general formula (I), the following general formula (II), the following general formula (III) and the following general formula (IV) (hereinafter, these repeating units may be described as "repeating unit (I)", "repeating unit (II)", "repeating unit (III)" and "repeating unit (IV)", respectively) (hereinafter, polyamic acids including these repeating units may be described as "polyamic acid (I)", "polyamic acid (II)", "polyamic acid (III)" and "polyamic acid (IV)", respectively).

[ chemical formula 4]

In the general formula (I):

R¹and R²Each independently is a hydrogen atom or a methyl group;

R³is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B¹is a divalent organic group.

[ chemical formula 5]

In the general formula (II):

R¹¹and R¹²Each independently is a hydrogen atom or a methyl group;

R¹³is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B¹¹is a divalent organic group.

[ chemical formula 6]

In the general formula (III):

R²¹and R²²Each independently is a hydrogen atom or a methyl group;

R²³is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B²¹is a divalent organic group.

[ chemical formula 7]

In the general formula (IV):

R³¹and R³²Each independently is a hydrogen atom or a methyl group;

R³³is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B³¹is a divalent organic group.

In the general formula (I), R¹And R²Preferably methyl. In the general formula (I), R³Preferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂. In the general formula (I), B¹And B in the general formula (A)^ASynonymously, it is preferably p-phenylene or-C₆H₄-O-C₆H₄-。

Examples of the polyamic acid (I) include polyamic acids comprising repeating units represented by the chemical formulae (I-2) and (I-3) (hereinafter, these may be referred to as "polyamic acid (I-2)" and "polyamic acid (I-3)", respectively).

[ chemical formula 8]

[ chemical formula 9]

In the general formula (II), R¹¹And R¹²Preferably methyl. In the general formula (II), R¹³Preferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂. In the general formula (II), B¹¹And B in the general formula (A)^ASynonymously, it is preferably p-phenylene or-C₆H₄-O-C₆H₄-。

Examples of the polyamic acid (II) include polyamic acids comprising repeating units represented by the chemical formulae (II-2) and (II-3) (hereinafter, these may be referred to as "polyamic acid (II-2)" and "polyamic acid (II-3)", respectively).

[ chemical formula 10]

[ chemical formula 11]

In the general formula (III), R²¹And R²²Preferably methyl. In the general formula (III),R²³preferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂. In the general formula (III), B²¹And B in the general formula (A)^ASynonymously, it is preferably p-phenylene or-C₆H₄-O-C₆H₄-。

In the general formula (IV), R³¹And R³²Preferably methyl. In the formula (IV), R³³Preferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂. In the general formula (IV), B³¹And B in the general formula (A)^ASynonymously, it is preferably p-phenylene or-C₆H₄-O-C₆H₄-。

The polyamic acid (A) is preferably a polyamic acid including at least one of the repeating units (I) to (IV), more preferably a polyamic acid including at least one of the repeating units selected from the group consisting of the repeating units (I) and (II), still more preferably a polyamic acid including the repeating unit (I) or (II), and particularly preferably a polyamic acid (I-2), (I-3), (II-2) or (II-3).

(end Structure of Polyamic acid)

The polyamic acid (a) can be any end group of an acid anhydride group and an amino group. The terminal group can be selected, for example, by using an excess of either the acid dianhydride or the diamine compound (i.e., by making the amount of one of the components excessive) during the synthesis reaction described later. When an acid anhydride group is used as a terminal group, the terminal structure may be an acid anhydride group as it is, a carboxylic acid may be produced by hydrolysis, or an ester may be produced by using an alcohol having 4 or less carbon atoms.

When the tetracarboxylic dianhydride is used in an excess amount relative to the diamine compound in the synthesis reaction of the polyamic acid (a), a monofunctional diamine compound may be further added to cap the terminal acid anhydride group with a monofunctional amine compound. Examples of the monofunctional amine compound include primary amines such as aniline, methylaniline, dimethylaniline, trimethylaniline, ethylaniline, diethylaniline, triethylaniline, aminophenol, methoxyaniline, aminobenzoic acid, benzidine, naphthylamine, and cyclohexylamine.

When the diamine compound is used in an excess amount to the acid anhydride after the synthesis reaction, a monofunctional acid anhydride may be further added to terminate the terminal amino group with a monofunctional acid anhydride. The monofunctional acid anhydride may be used without any particular limitation as long as it can be converted into a monofunctional acid anhydride of a dicarboxylic acid or a tricarboxylic acid after hydrolysis. Examples of such monofunctional acid anhydrides include maleic anhydride, methylmaleic anhydride, dimethylmaleic anhydride, succinic anhydride, nadic anhydride, 4-phenylethynylphthalic anhydride, 4-ethynylphthalic anhydride, phthalic anhydride, methylphthalic anhydride, dimethylphthalic anhydride, trimellitic anhydride, naphthalic anhydride, 7-oxabicyclo [2.2.1] heptane-2, 3-dicarboxylic anhydride, bicyclo [2.2.2] oct-5-ene-2, 3-dicarboxylic anhydride, octahydro-1, 3-dioxoisobenzofuran-5-carboxylic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, dimethylcyclohexanedicarboxylic anhydride, 1,2,3, 6-tetrahydrophthalic anhydride and methyl-4-cyclohexene-1, 2-dicarboxylic anhydride.

The polyamic acid (a) preferably contains substantially no dicarboxylic structure derived from a tetracarboxylic acid at the molecular end of the polyamic acid (a) (more specifically, a polyamic acid containing at least one selected from the group consisting of the repeating units (I) to (IV)).

In the present specification, the term "derived from tetracarboxylic acid" is not limited to tetracarboxylic acid alone, and may be derived from a derivative of tetracarboxylic acid (for example, tetracarboxylic dianhydride). "substantially free" means that the whole molecular terminal of the polyamic acid (A) does not have a dicarboxylic acid structure in a proportion of preferably 95% or more, more preferably 98% or more, further preferably 99% or more, and particularly preferably 100%.

More preferably, the polyamic acid (A) has a molecular end comprisingThe amino group derived from a diamine, more preferably the amino group (-NH) in a polyamic acid₂) The ratio (terminal amino group concentration) of (B) is in the range of 0.001 to 0.1 mol/kg.

The terminal amino group concentration of the polyamic acid (a) can be obtained by calculating the formula (C) below.

(terminal amino group concentration) 17 × (Σ XB- Σ XA-0.5 × Σ XC)/Σ (WB × PB) + Σ (WA × PA) · (C)

In the formula (C), the compound represented by the formula (A),

WB is the amount (g) of the diamine compound added;

MB is the molecular weight of the diamine compound;

PB is the purity (%) of the diamine compound,

XB is the molar amount of diamine compound added and is determined by the following formula (C-1):

XB＝(WB×PB)/(100×MB)···(C-1)

WA is the amount (g) of tetracarboxylic acid added;

MA is the molecular weight of the tetracarboxylic acid;

PA is the purity (%) of tetracarboxylic acid;

XA is the molar amount of tetracarboxylic acid added, and is determined by the following formula (C-2):

XA＝(WA×PA)/(100×MA)···(C-2)

WC is the amount (g) of monofunctional carboxylic anhydride acid added as described later;

MC is the molecular weight of the monofunctional carboxylic anhydride;

PC is the purity (%) of the monofunctional carboxylic anhydride;

XC is the added molar amount of monofunctional carboxylic anhydride and is determined by the following formula (C-3):

XC＝(WC×PC)/(100×MC)···(C-3)。

the terminal amino group concentration of the polyamic acid (a) can be determined from the mass of the reaction product of the polyamic acid (a) and the like in the above manner, and can also be calculated from the finished polyamic acid composition. For example, when the polyamic acid is dissolved in a water-soluble solvent, the measurement can be performed by dropping an inorganic acid such as hydrochloric acid.

[ preparation method of Polyamic acid composition ]

An example of the method for producing the polyamic acid composition is described below. The polyamic acid composition (a) can be obtained, for example, by reacting a tetracarboxylic acid compound having a steroid structure with a diamine compound. More specifically, polyamic acid (A) is synthesized by a method based on the reactions represented by the reaction formulae (R-1) and (R-2) (hereinafter, these may be referred to as "reaction (R-1)" and "reaction (R-2)", respectively), or the reactions represented by the reaction formulae (R-1) and (R-2). A tetracarboxylic dianhydride having a steroid structure is synthesized in the reaction (R-1), and a polyamic acid (A) is synthesized in the reaction (R-2).

[ chemical formula 12]

[ chemical formula 13]

In the reactions (R-1) and (R-2),

r in the general formula (C) and the general formula (E)^A、R^BAnd R^CAre each independently of R in the formula (A)^A、R^BAnd R^CSynonymy;

g in the general formula (D) and G in the general formula (A)¹And G²Is synonymous with at least one of;

g in the formula (E)¹And G²Are each independently of G in the formula (A)¹And G²Synonymy;

b in the formula (E)³And B⁴And B in the general formula (A)³And B⁴Synonymy;

z in the general formula (D) is-CH₂X (halomethyl) or-C (═ O) X, X being a halogen atom, preferably a chlorine atom or a bromine atom, more preferably a chlorine atom;

B³and B⁴is-CH₂When Z is-CH₂X；B³And B⁴When is-C (═ O) -, Z is-C (═ O) X;

m represents the number of repeating units (degree of polymerization).

(reaction (R-1))

In the reaction (R-1), 1 equivalent of the steroid diol represented by the general formula (C) (hereinafter, sometimes referred to as "steroid diol (C)") is reacted with 2 equivalents of the carboxylic anhydride represented by the general formula (D) (hereinafter, sometimes referred to as "carboxylic anhydride (D)") to obtain 1 equivalent of the tetracarboxylic dianhydride represented by the general formula (E) (hereinafter, sometimes referred to as "tetracarboxylic dianhydride (E)").

B is as follows³And B⁴The description is divided into two cases.

(B³And B⁴is-CH₂When is)

The reaction (R-1) is an etherification reaction.

Z is-CH₂X。

Examples of the steroid diol (C) include steroid diols represented by the chemical formulas (C-1) and (C-2) (hereinafter, these may be referred to as "steroid diol (C-1)" and "steroid diol (C-2)", respectively).

[ chemical formula 14]

Examples of the carboxylic anhydride (D) include carboxylic anhydrides represented by the general formula (D-1) (3-halomethylphthalic anhydride, hereinafter sometimes referred to as "carboxylic anhydride (D-1)") and carboxylic anhydrides represented by the general formula (D-2) (1-halomethylcyclohexanedicarboxylic anhydride, hereinafter sometimes referred to as "carboxylic anhydride (D-2)").

[ chemical formula 15]

In the general formulae (D-1) and (D-2), X is a chlorine atom or a bromine atom.

The carboxylic anhydride (D-1) is preferably 3-chloromethylphthalic anhydride or 3-bromomethylphthalic anhydride. The carboxylic anhydride (D-2) is preferably 1-chloromethyl-3, 4-cyclohexanedicarboxylic anhydride or 1-bromomethyl-3, 4-cyclohexanedicarboxylic anhydride.

In the etherification reaction, for example, carboxylic anhydride (D) is dehydrohalogenated in a solvent under a basic catalyst, and then reacted with steroid diol (C), thereby obtaining tetracarboxylic acid having a steroid structure (intermediate product). Then, the intermediate product is dehydrated to convert the two carboxyl groups thereof into a dicarboxylic anhydride structure. Thus, tetracarboxylic dianhydride (E) was obtained.

Examples of the solvent used in the etherification reaction include aromatic hydrocarbons such as toluene and benzene; ethers such as diethyl ether, methyl ethyl ether, methyl butyl ether, tetrahydrofuran and dioxane; and other acetone, water, and the like.

Examples of the basic catalyst used in the ether reaction include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, and alkali metal carbonates such as potassium carbonate.

The reaction temperature of the etherification reaction is usually-50 to 250 ℃, preferably 0 to 200 ℃. The reaction time of the etherification reaction is usually 0.1 to 20 hours, preferably 0.5 to 10 hours.

For the dehydration of the intermediate product, the intermediate product is preferably reduced in a dehydration catalyst such as an acetic anhydride.

After dehydration of the intermediate product, the tetracarboxylic dianhydride having a steroid structure can be purified. Examples of the purification method include recrystallization and sublimation. Here, the solvent used for recrystallization is preferably a good solvent that undergoes ring opening of an acid anhydride structure when heated, becomes a poor solvent when cooled, and does not deteriorate during recrystallization. Examples of such a solvent include ketone solvents such as acetone and methyl ethyl ketone, and acetic anhydride solvents.

For example, tetracarboxylic dianhydrides represented by the chemical formulas (E-2) and (E-3) (hereinafter referred to as "tetracarboxylic dianhydride (E-2)" and "tetracarboxylic dianhydride (E-3)", respectively) can be obtained by an etherification reaction.

[ chemical formula 16]

[ chemical formula 17]

(B³And B⁴is-C (═ O) -Time)

The reaction (R-1) is an esterification reaction.

Z is-C (═ O) X.

Examples of the steroid diol (C) include steroid diols (C-1) and (C-2).

Examples of the carboxylic anhydride (D) include carboxylic anhydride (3-halomethylphthalic anhydride: hereinafter, sometimes referred to as "carboxylic anhydride (D-3)") of the formula (D-3) and carboxylic anhydride (1-halomethylcyclohexanedicarboxylic anhydride: hereinafter, sometimes referred to as "carboxylic anhydride (D-4)") of the formula (D-4).

[ chemical formula 18]

In the general formulae (D-3) and (D-4), X is preferably a chlorine atom or a bromine atom. The carboxylic anhydride (D-3) is preferably chlorinated trimellitic anhydride or brominated trimellitic anhydride.

In the esterification reaction, for example, a carboxylic anhydride (D) is reacted in a solvent under an acidic catalyst or a basic catalyst to obtain a tetracarboxylic acid having a steroid structure (intermediate product). Then, the intermediate product is dehydrated to convert the two carboxyl groups thereof into carboxylic anhydride structures. Thus, tetracarboxylic dianhydride (E) was obtained.

As the solvent used in the esterification reaction, a solvent that can dissolve the reactant (more specifically, steroid diol (C) and carboxylic anhydride (D)) and the intermediate product (tetracarboxylic acid (E) having a steroid structure) and does not change its quality during the reaction itself is preferably used.

Examples of the solvent used in the esterification reaction include aromatic hydrocarbons such as benzene and toluene; ethers such as diethyl ether, tetrahydrofuran, dioxane, 1, 2-dimethoxyethane, anisole, ethylene glycol dimethyl ether and ethylene glycol diethyl ether; and water and the like. These solvents may be used alone or in combination of two or more.

As the catalyst used in the esterification reaction, an acid catalyst or a base catalyst which is generally used as a catalyst for the esterification reaction can be used. The kind of the catalyst is appropriately selected depending on the kind of the carboxylic anhydride (C). Examples of the acid catalyst include hydrochloric acid, sulfuric acid, trifluoroacetic anhydride, methanesulfonic acid, p-toluenesulfonic acid, boron trifluoride diethyl ether complex, and boron trifluoride dibutyl ether complex. Examples of the base catalyst include triethylamine, tributylamine, pyridine, picoline, lutidine, dimethylaniline, 1, 4-diazabicyclo [2.2.2] octane, 1, 8-diazabicyclo [5.4.0] undecene, tetramethylurea, sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate.

The catalyst is used in an appropriate amount according to the kind of the catalyst. The catalyst is usually used in an amount of a substance within a range of 0.001 to 5.0 mol, preferably 0.1 to 2.5 mol, based on 1 mol of the carboxylic anhydride (D).

The esterification reaction temperature is usually-50 to 250 ℃ and preferably 0 to 200 ℃. The reaction time is usually 0.1 to 20 hours, preferably 0.5 to 10 hours.

The dehydration of the intermediate product is preferably carried out by reducing the intermediate product in a dehydration catalyst such as acetic anhydride.

After dehydration of the intermediate product, the tetracarboxylic dianhydride having a steroid structure can be purified. Examples of the purification method include recrystallization and sublimation. Here, the solvent used for recrystallization is preferably a good solvent that undergoes ring opening of an acid anhydride structure when heated, becomes a poor solvent when cooled, and does not deteriorate during recrystallization. Examples of such a solvent include ketone solvents such as acetone and methyl ethyl ketone, and acetic anhydride solvents.

By the esterification reaction, for example, tetracarboxylic dianhydrides represented by the chemical formulas (E-4) and (E-5) (hereinafter, referred to as "tetracarboxylic dianhydride (E-4)" and "tetracarboxylic dianhydride (E-5)", respectively) can be obtained.

[ chemical formula 19]

[ chemical formula 20]

(reaction (R-2))

In the reaction (R-2), 1 equivalent of tetracarboxylic dianhydride (E) and 1 equivalent of a diamine compound represented by the general formula (F) (hereinafter, sometimes referred to as "diamine compound (F)") are polymerized to obtain polyamic acid (a). B in the formula (F) ^AAnd B in the general formula (A)^ASynonymously.

(diamine Compound)

The diamine compound (F) is preferably a compound in which two amine groups are bonded to a divalent organic group including at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, and more preferably a diamine compound represented by the general formula (F-2).

H₂N-B^A2-(Y²-B^A2)_n2-NH₂···(F-2)

In the general formula (F-2), B^A2、Y²And n2 is independently from B in the general formula (A-2)^A1、Y¹And n1 are synonymous.

In the general formula (F-2), B^A2Preferably a monocyclic arylene group having 6 to 14 carbon atoms and a cycloalkylene group having 5 to 7 carbon atoms, more preferably a phenylene group and a cyclohexanediyl group, still more preferably a p-phenylene group and a 1, 4-cyclohexanediyl group, and particularly preferably a p-phenylene group.

In the general formula (F-2), n2 is preferably an integer of 0 to 2, more preferably 0 or 1.

In the general formula (F-2), Y²Preferably a single bond, an alkyl group having 1 to 3 carbon atoms, and a hetero atom, more preferably a single bond, a methyl group, and an oxygen atom, and still more preferably an oxygen atom.

In the general formula (F-2), B^A2The substituent which may be present is preferably a carbon atomAn alkyl group having 1 to 3 carbon atoms and a halogenated alkyl group having 1 to 3 carbon atoms, more preferably a methyl group and a halogenated methyl group, and still more preferably a methyl group and a trifluoromethyl group.

Examples of the diamine compound (F) include aromatic diamines and aliphatic diamines.

The aromatic diamine has at least one aromatic ring. Examples of the aromatic diamine include 1, 3-phenylenediamine, 1, 4-phenylenediamine (p-Phenylenediamine (PDA)), 2, 4-diaminotoluene, 2, 6-diaminotoluene, 3, 4-diaminotoluene, 4, 5-dimethyl-1, 2-phenylenediamine, 2, 5-dimethyl-1, 4-phenylenediamine, 2, 6-dimethyl-1, 4-phenylenediamine, 2,3,5, 6-tetramethyl-1, 4-phenylenediamine, 3-aminobenzylamine, m-xylylenediamine, p-xylylenediamine, 1, 5-diaminonaphthalene, 2 '-dimethylbiphenyl-4, 4' -diamine, 2 '-bis (trifluoromethyl) diaminobiphenyl, 3' -dimethoxybenzidine, and the like, 4,4 ' -diaminooctafluorobiphenyl, 3 ' -diaminodiphenylmethane, 3,4 ' -diaminodiphenylmethane, 4 ' -methylenebis (2, 6-diethylaniline), 4 ' -methylenebis (2-ethyl-6-methylaniline), 4 ' -ethylenediphenylamine, 4 ' -diaminodiphenyl ether (ODA), 3,4 ' -diaminodiphenyl ether, 3 ' -diaminodiphenyl ether, 4 ' -diaminodiphenyl ether, 2 ' -bis (trifluoromethyl) -4,4 ' -diaminodiphenyl ether, 1, 3-bis (4-aminophenoxy) benzene, 1, 3-bis (3-aminophenoxy) benzene, 3-diaminodiphenylmethane, 4 ' -methylenebis (2-ethyl-6-methylaniline), 1, 4-bis (4-aminophenoxy) benzene, 1, 4-bis (4-amino-2-trifluoromethylphenoxy) benzene, 4 ' -bis (4-aminophenoxy) biphenyl, 4 ' -diamino-3, 3 ' -dimethyldiphenylmethane, bis [4- (4-aminophenoxy) phenyl ] sulfone, bis [4- (3-aminophenoxy) phenyl ] sulfone, 2-bis (4-aminophenyl) hexafluoropropane, 2-bis (3-aminophenyl) hexafluoropropane, 2 ' -bis [4- (4-aminophenoxy) phenyl ] propane, 2 ' -bis [4- (4-aminophenoxy) phenyl ] hexafluoropropane, 2-bis (3-amino-4-tolyl) hexafluoropropane, α, α '-bis (4-aminophenyl) -1, 4-diisopropylbenzene, bis (2-aminophenyl) sulfide, bis (4-aminophenyl) sulfide, 3' -diaminodiphenylsulfone, 4 '-diaminodiphenylsulfide, 4' -diaminobenzophenone, 3 '-diaminobenzophenone, 4' -diaminobenzoylaniline, 1, 4-bis (4-aminophenoxy) benzene, bis (4-aminophenyl) terephthalic acid, 2, 7-diaminofluorene and 9, 9-bis (4-aminophenyl) fluorene.

Examples of the aliphatic diamine include 1, 3-cyclohexanediamine, 1, 4-cyclohexanediamine, 1, 3-bis (aminomethyl) cyclohexane, 1-bis (4-aminophenyl) cyclohexane, 4 '-diaminodicyclohexylmethane, 4' -methylenebis (2-methylcyclohexylamine), 4 '-methylenebis (2, 6-dimethylcyclohexylamine), 4' -diaminodicyclohexylpropane, bicyclo [2.2.1] heptane-2, 3-diamine, bicyclo [2.2.1] heptane-2, 5-diamine, bicyclo [2.2.1] heptane-2, 6-diamine, bicyclo [2.2.1] heptane-2, 7-diamine, 2, 3-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2, 5-bis (aminomethyl) -bicyclo [2.2.1] heptane, 2, 6-bis (aminomethyl) -bicyclo [2.2.1] heptane and 3(4),8(9) -bis (aminomethyl) tricyclo [5.2.1.0(2,6) ] decane.

The diamine compound (F) may be used alone or in combination of two or more.

Among the diamine compounds, the diamine compound (E) is preferably an aromatic diamine such as p-phenylenediamine, 2 '-dimethylbiphenyl-4, 4' -diamine, 2 '-bis (trifluoromethyl) diaminobiphenyl, 2' -bis (trifluoromethyl) -4,4 '-diaminodiphenyl ether, 1, 4-bis (4-amino-2-trifluoromethylphenoxy) benzene, and 4, 4' -diaminodiphenyl ether; aliphatic diamines such as 1, 4-cyclohexanediamine, 4 '-diaminodicyclohexylmethane, and 4, 4' -methylenebis (2-methylcyclohexylamine) (4,4 '-methylenebis (2, 6-dimethylcyclohexylamine)), and combinations of these diamine compounds, and more preferably p-phenylenediamine, 4' -diaminodiphenyl ether, and combinations of both.

(tetracarboxylic acid Compound)

The polyamic acid (a) may have a repeating unit derived from a tetracarboxylic dianhydride other than the tetracarboxylic dianhydride (E) having a steroid structure. The tetracarboxylic acid anhydride (hereinafter, sometimes referred to as "tetracarboxylic acid dianhydride (E-X)") is preferably used for synthesis of the polyamic acid (a) because the tetracarboxylic acid dianhydride does not generate a reaction by-product.

Examples of the tetracarboxylic acid dianhydride (E-X) include aromatic acid dianhydrides, aliphatic acid dianhydrides, and aliphatic ester acid dianhydrides, as acid dianhydrides used in the production of conventional polyimides, provided that the obtained polyamic acid (a) has the effects of the present invention.

Examples of the aromatic acid dianhydride include pyromellitic dianhydride, 1,2,3, 4-benzenetetracarboxylic dianhydride, 3,3 ', 4,4 ' -biphenyltetracarboxylic dianhydride, 2,3,3 ', 4 ' -biphenyltetracarboxylic dianhydride, 2,3,2 ', 3 ' -biphenyltetracarboxylic dianhydride, 3,3 ', 4,4 ' -diphenylmethane tetracarboxylic dianhydride, 2,3,3 ', 4 ' -diphenylmethane tetracarboxylic dianhydride, 3,3 ', 4,4 ' -benzophenone tetracarboxylic dianhydride, 2,3,3 ', 4 ' -benzophenone tetracarboxylic dianhydride, 3,4 ' -oxydiphthalic anhydride, 4,4 ' -oxydiphthalic anhydride, 3,3 ' -oxydiphthalic anhydride, and the like, 3,4,3 ', 4' -diphenylsulfone tetracarboxylic dianhydride, 2,3,2 ', 3' -diphenylsulfone tetracarboxylic dianhydride, 4 '- [ isopropylidenebis [ (1, 4-phenylene) ] oxy ] diphthalic anhydride, 5' -isopropylidenebis (phthalic anhydride), 3,3 '-isopropylidenebis (phthalic anhydride), 4' - (1, 4-phenylenedioxy) diphthalic anhydride, 4 '- (1, 3-phenylenedioxy) diphthalic anhydride, 5' - [ oxybis (4, 1-phenyleneoxy) ] diphthalic anhydride and 5, 5' - [ sulfonyl bis (4, 1-phenyleneoxy) ] bisphthalic anhydride.

Further, the aromatic acid dianhydride may have a silicon atom, fluorine atom, ester structure, or fluorene cardo structure. More specifically, examples of the silicon-containing acid dianhydride include 4,4 '- (dimethylsilylene) bisphthalic acid 1,2: 1', 2 '-dianhydride, 4' - (methylethylsilyl) bisphthalic acid 1,2:1 ', 2' -dianhydride, 4 '- (phenyl (methyl) silyl) bisphthalic acid 1,2: 1', 2 '-dianhydride, 4' -diphenyl, and silylene bisphthalic acid 1,2:1 ', 2' -dianhydride.

Examples of the fluorine-containing acid dianhydride include 4,4 ' - (2, 2-hexafluoroisopropylidene) diphthalic anhydride, 3 ' - (2, 2-hexafluoroisopropylidene) diphthalic anhydride, and 4,4 ' - [2, 2-hexafluoroisopropylidene [ (1, 4-phenylene) oxy ] ] diphthalic anhydride. Examples of the fluorene cardo structure-based acid dianhydride include 5,5 ' - [ -diylbis (4, 1-phenyleneoxy) ] bis (isobenzofuran-1, 3-dione) and 5,5 ' - [ 9H-fluorene-9, 9-diylbis (1,1 ' -diphenyl-5, 2-diyloxy) ] bis (isobenzofuran-1, 3-dione).

As the ester acid dianhydride, for example, examples thereof include ethylene glycol-bis (trimellitic anhydride), 1, 4-phenylene-bis (trimellitic anhydride), 1, 3-phenylene-bis (trimellitic anhydride), 1, 2-phenylene-bis (trimellitic anhydride), bis (1, 3-dihydro-1, 3-dioxoisobenzofuran-5-carboxylic acid) -2-acetoxypropane-1, 3-diyl, 5 '- [ ethylenebis (oxy) ] bis (isobenzofuran-1, 3-dione), bis (1, 3-dihydro-1, 3-dioxo-5-isobenzofurancarboxylic acid) oxybis (methyleneoxymethylene) and 4, 4' - [ isopropylidenebis (4, 1-phenyleneoxycarbonyl) ] bisphthalic dianhydride.

Examples of the aliphatic acid dianhydride include tetracarboxylic dianhydrides containing an aliphatic ring. The aliphatic ring may also be condensed with an aromatic ring. Examples of the aliphatic acid dianhydride include 1,1 ' -bicyclohexane-3, 3 ', 4,4 ' -tetracarboxylic dianhydride, 1 ' -bicyclohexane-2, 3,3 ', 4 ' -tetracarboxylic dianhydride, 1 ' -bicyclohexane-2, 3,2 ', 3 ' -tetracarboxylic dianhydride, cyclohexane-1, 2,4, 5-tetracarboxylic dianhydride, 1,2,3, 4-tetracarboxylic dianhydride, 1,3,3a,4,5,9 b-hexahydro-5 (tetrahydro-2, 5-dioxo-3-furanyl) naphtho [1,2-c ] furan-1, 3-dione, 1,2,3, 4-butanetetracarboxylic dianhydride, 1,2,3, 4-cyclobutanetetracarboxylic dianhydride (CHDA), 1,2,3, 4-cyclopentanetetracarboxylic dianhydride, 5- (2, 5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1, 2-dicarboxylic anhydride, bicyclo [2.2.2] oct-7-ene-2, 3,5, 6-tetracarboxylic dianhydride, bicyclo [2.2.2] octane-2, 3,5, 6-tetracarboxylic acid-2, 3:5, 6-dianhydride, bicyclo [2.2.1] heptane-2, 3,5, 6-tetracarboxylic acid-2, 3:5, 6-dianhydride, and hexahydro-3 a,11a- (2, 5-dioxotetrahydrofuran-3, 4-diyl) phenanthro [9,10-c ] furan-1, 3-dione.

Examples of the aliphatic ester acid dianhydride include bis (1, 3-dioxo-1, 3,3a,4,5,6,7,7 a-octahydroisobenzofuran-5-carboxylic acid) diphenyl-4, 4' -diyl, bis (1, 3-dioxo-1, 3,3a,4,5,6,7,7 a-octahydroisobenzofuran-5-carboxylic acid) 1, 4-phenylene and bis (1, 3-dioxo-1, 3,3a,4,5,6,7,7 a-octahydroisobenzofuran-5-carboxylic acid) -2-methyl-1, 4-phenylene.

As the tetracarboxylic dianhydride (E-X), one of these tetracarboxylic dianhydrides may be used alone or two or more thereof may be used in combination.

Among these tetracarboxylic dianhydrides, the tetracarboxylic dianhydride (E-X) preferably does not contain an aromatic ring from the viewpoint of suppressing the formation of intramolecular and intermolecular CT complexes and improving the transparency of the polyimide. In addition, the tetracarboxylic dianhydride (E-X) preferably has a cyclic structure rather than a linear or branched structure from the viewpoint of improving the mechanical strength of the polyimide.

That is, the tetracarboxylic dianhydride (E-X) is preferably a tetracarboxylic dianhydride containing an aliphatic ring without an aromatic ring, from the viewpoint of improving the transparency, durability and mechanical strength of the polyimide. More specifically, the tetracarboxylic dianhydride (E-X) is preferably 1,2,3, 4-cyclobutanetetracarboxylic dianhydride, 1,2,4, 5-cyclopentanetetracarboxylic dianhydride, 1,2,4, 5-cyclohexanetetracarboxylic dianhydride, bicyclo [2,2,1] heptane-2, 3,5, 6-tetracarboxylic dianhydride, bicyclo [2,2,2] octane-2, 3,5, 6-tetracarboxylic dianhydride, 3 ', 4, 4' -dicyclohexyltetracarboxylic dianhydride, and 1,2, 4-cyclohexanetricarboxylic anhydride, and more preferably 1,2,3, 4-cyclobutanetetracarboxylic dianhydride, 1,2,4, 5-cyclohexanetetracarboxylic dianhydride, and 3,3 ', 4, 4' -dicyclohexyltetracarboxylic dianhydride.

When the tetracarboxylic anhydride (E-X) is used for the synthesis of the polyamic acid (A), the ratio of the tetracarboxylic anhydride (E) to the tetracarboxylic anhydride (E-X) can be suitably selected, and for example, the ratio "tetracarboxylic anhydride (E): tetracarboxylic anhydride (E-X)" (molar ratio) may be in the range of 40:60 to 100:0, preferably in the range of 50:50 to 100:0, and more preferably in the range of 80:20 to 100: 0.

The ratio of the tetracarboxylic acid compound (E) and the diamine compound (F) used for the synthesis of the polyamic acid (a) (the ratio of the amounts of addition) is preferably 0.5 to 1.5 equivalents of the acid anhydride group of the tetracarboxylic acid compound (E) to 1 equivalent of the amino group contained in the diamine compound (F), and more preferably 0.8 to 1 equivalent of the acid anhydride group of the tetracarboxylic acid compound (E) to 1 equivalent of the amino group contained in the diamine compound (F). The ratio is preferably 0.5 to 0.9 equivalent from the viewpoint of making the molecular end of the polyamic acid (a) contain an amino group derived from the diamine compound (F).

In addition, the case where the tetracarboxylic dianhydride (E-X) is not contained in the above ratio is explained. In the case of containing the tetracarboxylic dianhydride (E-X), the above ratio is a ratio of the total amount of the added amounts of the tetracarboxylic dianhydride (E) and the tetracarboxylic dianhydride (E-X) to the added amount of the diamine compound (F).

The reaction temperature in the reaction (R-2) is preferably-20 to 150 ℃, and more preferably 0 to 100 ℃. The reaction time is preferably 0.2 to 120 hours, and more preferably 0.5 to 72 hours. Further, the synthesis of the polyamic acid (a) can be preferably carried out in a solvent. The solvent is not particularly limited as long as the synthesized polyamide acid can be dissolved or dispersed in the solvent, and examples thereof include aprotic polar solvents such as N-methylpyrrolidone, N-dimethylacetamide, N-dimethylformamide, dimethyl sulfoxide, γ -butyrolactone, tetramethylurea, and hexamethylphosphoric triamide; and phenolic solvents such as m-cresol, xylenol, phenol and halogenated phenol. The amount of the solvent (a: wherein the good solvent and the poor solvent described later are used together, the total amount of both) is preferably such that the total amount (b) of the tetracarboxylic anhydride (E) and the diamine compound (F) is 0.1 to 30% by weight relative to the total amount (a + b) of the reaction solution.

Examples of the solvent used for the synthesis of the polyamic acid (a) include alcohols, ketones, esters, ethers, halogenated hydrocarbons, and hydrocarbons. These solvents may be used alone or in combination of two or more. These solvents are considered to be poor solvents for conventional polyamic acids and polyimides. These solvents can be used in a range in which the polyamic acid (a) is not precipitated. Specifically, the solvent can be used as a mixed solvent in which a poor solvent is mixed with a good solvent. The proportion of the poor solvent to the total of the good solvent and the poor solvent is preferably 25% by weight or less, and more preferably 10% by weight or less. In addition, as the good solvent for polyamic acid and polyimide, dimethylacetamide, N-methylpyrrolidone (NMP), and formaldehyde are generally cited.

Examples of the alcohol include monohydric alcohols such as methanol, ethanol, isopropanol, cyclohexanol and ethylene glycol monomethyl ether; ethylene glycol, propylene glycol, 1, 4-butanediol, triethylene glycol.

Examples of the ketone include acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, and cyclohexanone.

Examples of the ester include ethyl lactate, butyl lactate, methyl acetate, ethyl acetate, butyl acetate, methylmethoxypropionate, ethylethoxypropionate, diethyl oxalate, diethyl malonate, isoamyl propionate, and isoamyl isobutyrate.

Examples of the ether include tetrahydrofuran, diethyl ether, diisoamyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol n-propyl ether, ethylene glycol isopropyl ether, ethylene glycol n-butyl ether, ethylene glycol dimethyl ether, ethylene glycol ethyl ether acetate, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monomethyl ether acetate, and diethylene glycol monoethyl ether acetate.

Examples of the halogenated hydrocarbon include halogenated aliphatic hydrocarbons such as dichloromethane, 1, 2-dichloroethane, 1, 4-dichlorobutane and trichloroethane, and halogenated aromatic hydrocarbons such as chlorobenzene and o-dichlorobenzene.

Examples of the hydrocarbon include aliphatic hydrocarbons such as hexane, heptane and octane, and aromatic hydrocarbons such as benzene, toluene and xylene.

In the above manner, a reaction solution in which the polyamic acid is dissolved or dispersed (preferably dissolved) can be obtained.

The reaction solution may be directly supplied to the polyamic acid composition, or may be supplied to the preparation of the polyamic acid composition after the polyamic acid contained in the reaction solution is separated.

The isolation of the polyamic acid can be carried out by the following method: a method of pouring the above reaction solution into a large amount of a poor solvent to obtain a precipitate, and drying the precipitate under reduced pressure, or a method of distilling off the solvent in the reaction solution under reduced pressure by an evaporator. Further, the polyamic acid can be purified by a method of dissolving the polyamic acid in a solvent again and then precipitating it with a poor solvent, or a method of performing a step of distilling off the polyamic acid under reduced pressure with an evaporator once or more.

(solvent)

Examples of the solvent contained in the polyamic acid composition include sulfoxide solvents such as dimethyl sulfoxide and diethyl sulfoxide; formamide solvents such as N, N-dimethylformamide and N, N-diethylformamide; acetamide solvents such as N, N-dimethylacetamide and N, N-diethylacetamide; pyrrolidone solvents such as N-methylpyrrolidone and N-vinylpyrrolidone; phenol solvents such as phenol, o-cresol, m-cresol or p-cresol, xylenol, halogenated phenol and catechol; ether solvents such as tetrahydrofuran, dioxane and dioxolane; alcohol solvents such as methanol, ethanol and butanol; butyl cellosolve, a cellosolve-type solvent; a carbonate solvent such as ethylene carbonate and propylene carbonate; gamma-butyrolactone such a carboxylic ester solvent; aromatic hydrocarbons such as toluene and xylene; an aqueous solvent such as water or a mixed solvent of water and a low molecular weight alcohol (more specifically, methanol, ethanol, ethylene glycol, glycerin, etc.); and 1, 3-dimethyl-2-imidazolidinone and hexamethylphosphoric triamide as other solvents. These solvents may be used alone or in combination of two or more.

When the solvent is an aqueous solvent, the energy consumption required for drying the solvent can be reduced, and therefore the solvent can be easily distilled off to produce a polyimide molded article from the polyamic acid composition.

The aqueous solvent may further contain a tertiary amine. When the solvent is an aqueous solution of a tertiary amine, an ammonium salt is formed between the carboxyl group contained in the repeating unit and the tertiary amine, and thus the polyamic acid is dissolved in the aqueous solvent. Examples of the tertiary amine compound include morpholine compounds such as triethylamine, imidazole compounds, methylmorpholine, ethylmorpholine and phenylmorpholine.

Of these solvents, most of the solvents are generally considered to be poor solvents for polyamic acid. Conventionally, as a solvent that can be used for polyamic acid, N-methylpyrrolidone is representative, but the kind of solvent is limited. Therefore, there are major limitations to the processing of polyamic acid (e.g., synthesis of polyamic acid, preparation of polyamic acid composition, etc.).

In contrast, since the polyamic acid (a) is dissolved or dispersed in the plurality of solvents at a concentration of 1 to 30% by weight, the polyamic acid composition of the first embodiment has excellent processability.

The amount of the tertiary amine to be added to the aqueous solvent can be appropriately selected within a range of 0.5 to 2 equivalents with respect to 1 equivalent of the carboxyl group in the polyamic acid. When the amount of the tertiary amine is in the range of 0.5 to 2 equivalents, the polyamic acid is dissolved in the aqueous solvent, and thickening or gelation with time due to a decrease in stability of the polyamic acid composition is less likely to occur.

Among these solvents, an aqueous solvent, a formamide solvent, an acetamide solvent, a pyrrolidone solvent, a carbonate solvent, a carboxylic acid ester solvent, and a combination of these solvents are preferable, and at least one solvent selected from a tertiary amine aqueous solution, N-diethylformamide, N-diethylacetamide, N-dimethylacetamide, N-dimethylformamide, N-methylpyrrolidone, ethylene carbonate, propylene carbonate, and γ -butyrolactone is more preferable.

When the concentration of the polyamic acid is 10% by weight, the viscosity of the polyamic acid composition (a) is preferably 10 to 10,000mPa · s from the viewpoint of improving mechanical strength. The viscosity of the polyamic acid composition (A) was measured at 22.0 ℃ using an E-type viscometer.

The content of the polyamic acid in the polyamic acid composition (a) is not particularly limited, and the polyamic acid (a) may be in the range of 1 to 30% by weight, preferably 1 to 25% by weight, as a solid component in the polyamic acid composition (a), and can be adjusted by an appropriate solvent ratio.

< second embodiment: polyimide composition >

The polyimide composition of the second embodiment of the present invention comprises a polyimide and a solvent. The polyimide composition is formed by dissolving or dispersing a polyimide (hereinafter, sometimes referred to as "polyimide (B)") containing a repeating unit represented by the following general formula (B) (hereinafter, sometimes referred to as "repeating unit (B)") in a solvent.

[ chemical formula 21]

In the general formula (B), in the formula (B),

R^Dand R^EEach independently is a hydrogen atom or a methyl group;

R^Fis a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B^Dis a divalent organic group;

B⁵and B⁶Each independently is-C (═ O) -or-CH₂-；

G³And G⁴Each independently contains at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, or a linear alkanetriyl group having 4 to 10 carbon atoms, and when the number of rings is two or more, the rings are fused rings.

In the general formula (B), R^D、R^EAnd R^FAre each independently of R in the formula (A)^A、R^BAnd R^CSynonymously. G³And G⁴Are each independently of G in the formula (A)¹And G²Synonymously. B is^DAnd B in the general formula (A)^ASynonymously.

B^DThe divalent organic group preferably contains at least one ring selected from the group consisting of an aliphatic ring and an aromatic ring, and more preferably a divalent organic group represented by the general formula (B-1).

-B^A3-(Y³-B^A3)_n3-···(B-1)

B in the formula (B-1)^A3、Y³And n3 are each independently substituted with B in the general formula (A-1)^A1、Y¹And n1 are synonymous.

B^A3Preferably a monocyclic ring having 6 to 14 carbon atomsAn arylene group or a cycloalkylene group having 5 to 7 carbon atoms, more preferably a phenylene group or a cyclohexanediyl group, still more preferably a p-phenylene group or a 1, 4-cyclohexanediyl group, and particularly preferably a p-phenylene group.

n3 preferably represents 0 or 1.

Y³Preferably a single bond, an alkylene group having 1 to 3 carbon atoms, or a hetero atom of an oxygen atom and a sulfur atom, more preferably a single bond, a methylene group, or an oxygen atom, and still more preferably an oxygen atom.

The polyimide in the polyimide composition of the second embodiment contains the repeating unit (B), and therefore has excellent transparency, mechanical strength, and durability for the following reasons in the same manner as the polyamic acid (a). Since the polyimide (B) has a bulky steroid structure, it is considered difficult to form an intermolecular or intramolecular CT complex having a light absorption band in the visible light region. This makes it difficult to form intermolecular and intramolecular CT complexes, and therefore, light absorption which causes deterioration of the polyimide (B) does not easily occur. Further, the polyimide (B) can have molecular chains of the polyimide (B) ordered to some extent by the cohesive property of the steroid moiety.

The repeating unit (B) preferably includes a repeating unit selected from the group consisting of the following general formula (V), the following general formula (VI), the following general formula (VII), and the following general formula (VIII) (hereinafter, these repeating units may be referred to as "repeating unit (V)", "repeating unit (VI)", "repeating unit (VII)", and "repeating unit (VIII)", respectively

"repeating unit (VIII)") (hereinafter, the polyamic acids containing these repeating units may be referred to as "polyimide (V)", "polyimide (VI)", "polyimide (VII)", and "polyimide (VIII)", respectively).

[ chemical formula 22]

In the general formula (V),

R⁴and R⁵Each independently is a hydrogen atom or a methyl group;

R⁶is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B²is a divalent organic group, and is a divalent organic group,

[ chemical formula 23]

In the general formula (VI), the compound represented by the formula (VI),

R¹⁴and R¹⁵Each independently is a hydrogen atom or a methyl group;

R¹⁶is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B¹²is a divalent organic group, and is a divalent organic group,

[ chemical formula 24]

In the general formula (VII),

R²⁴and R²⁵Each independently is a hydrogen atom or a methyl group;

R²⁶is a hydrogen atom, an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 10 carbon atoms;

B²²is a divalent organic group, and is a divalent organic group,

[ chemical formula 25]

In the general formula (VIII),

R³⁴and R³⁵Each independently is a hydrogen atom or a methyl group;

R³⁶is a hydrogen atom or an alkyl group having 1 to 20 carbon atoms;

B³²is a divalent organic group.

In the general formula (V), R⁴And R⁵Preferably methyl. In the general formula (V), R⁶Preferably having 1 to up to 1 carbon atoms10 alkyl or alkenyl having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂. In the general formula (V), B²Preferably p-phenylene or-C₆H₄-O-C₆H₄-。

Examples of the polyimide (V) include polyimides comprising repeating units represented by the following chemical formulae (V-2) and (V-3) (hereinafter, these may be referred to as "polyimide (V-2)" and "polyimide (V-3)", respectively).

[ chemical formula 26]

[ chemical formula 27]

In the general formula (VI), R¹⁴And R¹⁵Preferably methyl. In the general formula (VI), R¹⁶Preferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂. In the general formula (VI), B¹²Preferably p-phenylene or-C₆H₄-O-C₆H₄-。

Examples of the polyimide containing the repeating unit represented by the general formula (VI) include polyimides containing repeating units represented by the following chemical formula (VI-2) and chemical formula (VI-3) (hereinafter, these may be referred to as "polyimide (VI-2)" and "polyimide (VI-3)", respectively).

[ chemical formula 28]

[ chemical formula 29]

In the general formula (VII), R²⁴And R²⁵Preferably methyl. In the general formula (VII), R²⁶Preferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂. In the general formula (VII), B²²Preferably p-phenylene or-C₆H₄-O-C₆H₄-。

In the general formula (VIII), R³⁴And R³⁵Preferably methyl. In the general formula (VIII), R³⁶Preferably an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms, more preferably-CH (CH)₃)(CH₂)₃CH(CH₃)₂or-CH (CH)₃)(CH₂)₂CH＝C(CH₃)₂. In the general formula (VIII), B³²Preferably p-phenylene or-C₆H₄-O-C₆H₄-。

The polyimide (B) is preferably a polyimide comprising at least one repeating unit selected from the group consisting of the repeating units (V) to (VIII), more preferably a polyimide comprising at least one repeating unit (V) and (VI), and still more preferably a polyimide comprising at least one repeating unit (V-2) and (VI-2).

(terminal Structure of polyimide)

The terminal group of the polyimide (B) can be selected from any of an acid anhydride group derived from the tetracarboxylic dianhydride (E) and an amino group derived from the diamine compound (F). The terminal group of the polyimide (B) can be selected, for example, by using an excessive amount of any one of the tetracarboxylic dianhydride (E) and the diamine compound (F) (that is, by making the amount of one component excessive) in the synthesis of the polyamic acid (a).

The terminal amino group concentration of the polyimide (B) can be determined by the same method as that of the polyamic acid (a).

From the viewpoint of improving the solubility or dispersibility of the polyimide (B) in a solvent, the polyimide (B) preferably does not contain a dicarboxylic acid structure derived from a tetracarboxylic acid at the molecular terminals of the polyimide (B) (for example, polyimides (V) to (VIII)). That is, the polyimide (B) preferably contains an amino group derived from a diamine at the molecular end of the polyimide (B), and the amino group (-NH) in the polyimide (B)₂) The ratio (terminal amino group concentration) of (B) is in the range of 0.001 to 0.1 mol/kg.

[ Synthesis method of polyimide composition ]

An example of a method for producing a polyimide composition will be described. The polyimide composition (B) is obtained, for example, by dehydrating and imidizing the polyamic acid (a) in the polyamic acid composition (a). More specifically, the polyimide (B) is synthesized by a method based on the reaction represented by the reaction formula (R-3) (hereinafter, sometimes referred to as "reaction (R-3)") or the reaction represented by the reaction formula (R-3).

[ chemical formula 30]

In the reaction formula (R-3),

r in the general formulae (A) and (B)^A、R^B、R^C、B^A、B³、B⁴、G¹、G²And m is independently from R in the general formula (A) in the reaction formula (R-2) ^A、R^B、R^C、B^A、B³、B⁴、G¹、G²And m is synonymous.

Further, as the method for producing the polyimide composition (B), it can also be obtained by dissolving or dispersing (preferably dissolving) the polyimide (B) (more specifically, the polyimides (V) to (VIII)) in a solvent.

The imidization reaction of the polyamic acid (a) in the polyamic acid composition will be described in detail below. Examples of the imidization reaction include a thermal imidization reaction in which the polyamic acid composition (a) is heated, and a chemical imidization reaction in which a catalyst and a dehydrating agent are added.

(thermal imidization)

The thermal imidization is performed by heating a solution of polyamic acid (a) to perform a dehydration imidization. In the thermal imidization, the reaction temperature is preferably in the range of about 100 ℃ to 250 ℃ and the reaction time is preferably 1 to 100 hours. The polyamic acid composition (a) can be used as it is as a solution of the polyamic acid (a) as a reactant (reactant) for thermal imidization.

(chemical imidization)

The chemical imidization is performed by heating the polyamic acid composition (a) in the presence of a catalyst and a dehydrating agent to perform a dehydration imidization. The chemical imidization reaction can be carried out, for example, by adding a catalyst and a dehydrating agent to a solution of the polyamic acid (a) and then carrying out the chemical imidization reaction in the same manner as the thermal imidization reaction, thereby obtaining a polyimide composition. In the chemical imidization, the reaction temperature is preferably in the range of normal temperature to about 150 ℃ and the reaction time is preferably 1 to 20 hours.

Examples of the dehydrating agent in the chemical imidization reaction include organic acid anhydrides. Examples of the organic acid anhydride include aliphatic acid anhydrides, aromatic acid anhydrides, alicyclic acid anhydrides, heterocyclic acid anhydrides, and mixtures of two or more of these organic acid anhydrides. Examples of the aliphatic acid anhydride include acetic anhydride. The amount of the dehydrating agent to be used is preferably 0.01 to 20 moles per 1 mole of the repeating unit of the polyamic acid (A).

Examples of the catalyst for the chemical imidization reaction include triethylamine, pyridine, picoline and quinoline. The amount of the catalyst to be used is preferably 0.01 to 10 mol based on 1 mol of the dehydrating agent to be used.

Examples of the solvent used in the chemical imidization reaction include solvents listed as solvents used in the synthesis of the polyamic acid (a).

(partial imidization)

The polyimide (B) may contain a repeating unit different from the repeating unit (a) in addition to the repeating unit (B). Examples of the different repeating unit include a repeating unit (a). That is, the polyimide (B) may be a polyamic acid-polyimide copolymer. The polyamic acid-polyimide copolymer can be obtained by adjusting the amount of the catalyst used in the chemical imidization reaction to adjust the ratio of the polyamic acid to the polyimide. Specifically, a catalyst such as pyridine and a dehydrating agent such as acetic anhydride are allowed to act on 1 equivalent of the polyamic acid residue, respectively, to convert substantially all of the polyamic acid residue into polyimide. That is, in the chemical imidization of polyamic acid, by setting the amounts of the catalyst and the dehydrating agent to 0.5 equivalent, respectively, a polyamic acid-polyimide copolymer including a polyimide structure and a polyamic acid structure in almost molar equivalents can be obtained. The imidization reaction is performed under the same reaction conditions (reaction temperature and reaction time) as the chemical imidization reaction described above.

The polyimide resin having a molecular structure insoluble in a solvent can be partially imidized by imidization, and thus can be dissolved in a solvent, and the coatability can be improved.

In the present specification, when the polyimide (B) has the repeating unit (a) in addition to the repeating unit (B), a polyamic acid-polyimide copolymer in which the ratio of the number of moles of the repeating unit (B) to the total number of moles of the repeating units (a) and (B) (molar ratio) is 80% or more is referred to as polyimide (B). Further, at this time, the polyamic acid-polyimide copolymer having a molar ratio of less than 80% is referred to as polyamic acid (a) (thus, polyamic acid (a) may have a repeating unit (B) in addition to the repeating unit (a)). The molar ratio can be calculated by means of an infrared spectrophotometer.

< third embodiment: polyimide molded article >

The polyimide molded body according to the third embodiment of the present invention is formed by molding the polyamic acid composition according to the first embodiment or the polyimide composition according to the second embodiment. That is, the polyimide molded body of the third embodiment contains a polyimide (B) (e.g., polyimides (V) to (VIII)).

The polyimide molded article is suitably used for, for example, a liquid crystal alignment film, a passivation film, a wire coating material, an adhesive film, a flexible electronic substrate film, a copper-clad laminate film, a laminated film, an electrical insulating film, a porous film for a fuel cell, a separator film, a heat-resistant film, an IC package, a resist film (resist film), a planarizing film, a lens such as a microlens array film, an optical fiber coating film, a display substrate, an optical waveguide, an optical filter, an adhesive sheet, an interlayer insulating film, a semiconductor insulating protective film, a TFT liquid crystal insulating film, a protective film for a solar cell, an antireflection film, and a film and sheet which can be used for an electronic material such as a flexible display substrate and a circuit substrate, and a belt member such as a belt for an image forming apparatus of an electrophotographic system (more specifically, an intermediate transfer belt, a fixing belt, a transfer belt, and the like).

The polyimide molded article is preferably suitable for applications such as display substrates, optical fibers, optical waveguides, optical filters, lenses, optical filters, pressure-sensitive adhesive sheets, interlayer insulating films, semiconductor insulating protective films, TFT liquid crystal insulating films, liquid crystal alignment films, protective films for solar cells, antireflection films, and films or sheets that can be used for electronic materials such as flexible display substrates or circuit substrates.

When used as a polyimide film, the film preferably has high transparency (e.g., transmittance) and high mechanical strength (e.g., pencil hardness). Further, the durability (pencil hardness after ultraviolet irradiation may be the same as or lower by about one order than before ultraviolet irradiation) is excellent, and the transparency (the transmittance after ultraviolet irradiation may be reduced by 10% or less, or by 7% or less, with respect to the transmittance before ultraviolet irradiation) may be maintained.

[ method for producing polyimide molded article ]

The polyimide molded body of the third embodiment can be manufactured by subjecting the polyamic acid composition of the first embodiment or the polyimide composition of the second embodiment to heat treatment and molding.

In the method for producing a polyimide molded article, the polyamic acid composition (a) is produced by heating to distill off the solvent and perform imidization. Alternatively, in the method for producing a polyimide molded article, the polyimide composition (B) is applied to a substrate and the solvent is distilled off. More specifically, the method for producing a polyimide molded body comprises: the method for producing a polyimide resin film includes a step of applying a polyamic acid composition (a) or a polyimide composition (B) to a substrate to form a coating film (hereinafter, sometimes referred to as "coating film forming step") and a step of subjecting the coating film to a heat treatment to form a polyimide molded product (hereinafter, sometimes referred to as "heating step").

(coating film formation step)

In the coating film forming step, the polyamic acid composition (a) or the polyimide composition (B) is applied to a substrate to form a coating film.

First, a substrate is prepared. The base material can be selected according to the use of the polyimide molded product to be produced.

Specifically, when the polyimide molded product is used as a liquid crystal alignment film, examples of the base material include a base material suitable for a liquid crystal element, for example, a silicon substrate, a glass substrate, or a substrate in which a metal film or an alloy film is formed on the surface of the substrate.

When the polyimide molded product is formed into a passivation film, examples of the base material include a semiconductor substrate on which an integrated circuit is formed, a wiring board on which wiring is formed, and a printed board on which electronic components and wiring are provided.

In the case where the polyimide molded article is used as a wire covering material, examples of the base material include various electric wires (more specifically, wires, rods, plates, and the like made of metal or alloy such as soft copper, hard copper, oxygen-free copper, chrome ore, and aluminum). When the polyimide molded article is molded into a tape shape and used as a tape-shaped electric wire covering material to be wound around an electric wire, various flat substrates or cylindrical substrates can be used as the base material.

When the polyimide molded product is formed into an adhesive film, examples of the base material include various molded products to be adhered (more specifically, various electrical parts such as a semiconductor chip and a printed circuit board).

Then, the polyamic acid composition (a) or the polyimide composition (B) is applied to a target substrate, thereby forming a coating film of the polyamic acid composition or the polyimide composition.

The method for applying the polyamic acid composition (a) or the polyimide composition (B) to the substrate is not particularly limited, and for example, known coating methods such as a spray coating method, a spin coating method, a roll coating method, a bar coating method, a slit coating method, an ink jet coating method, a spin coating method, a dip coating method, and a casting method can be mentioned depending on the viscosity of the polyamic acid composition (a) or the polyimide composition (B).

The thickness of the coating film can be appropriately selected depending on the type and use of the substrate.

(heating step)

In the heating step, the coating film is subjected to a heating treatment to form a polyimide molded body.

Specifically, first, the coating film of the polyamic acid composition (a) or the polyimide composition (B) is subjected to a drying treatment. By this drying treatment, a dried film is formed. In addition, in the dried film of the coating film of the polyamic acid composition (A), imidization of the polyamic acid (A) did not occur.

For the drying treatment of the coating film, a conventional heating drying oven can be used. Examples of the atmosphere in the drying furnace include the atmosphere, inert gases (more specifically, nitrogen gas, argon gas, etc.), and vacuum. The drying temperature may be appropriately selected depending on the boiling point of the solvent for dissolving the polyamic acid composition (A) or the polyimide composition (B), and is usually 80 to 350 ℃, preferably 100 to 320 ℃, and more preferably 120 to 270 ℃. The drying time may be appropriately selected depending on the thickness, concentration and kind of solvent, and is, for example, about 1 second to 360 minutes. In addition, it is also effective to blow hot air during heating. The temperature may be increased stepwise during heating, or may be increased without changing the speed of the hot air.

Then, the dried film is subjected to a heat treatment. Thereby forming a polyimide molded body. The heating temperature is, for example, 150 to 400 ℃ and preferably 200 to 300 ℃. The heating time is, for example, 20 to 60 minutes. In the case of performing the heating treatment, the temperature may be gradually raised in stages or at a constant rate until the final temperature of the heating is reached. In addition, the coating film of the polyamic acid (a) undergoes imidization reaction by heat treatment.

Through the above steps, a polyimide molded body can be formed. In this way, for example, a product having a polyimide molded body as a coating film can be obtained.

In addition, the method for producing the polyimide molded product may be a method in which the polyimide molded product is taken out from the base material and post-processed as necessary. For example, the polyimide molded product may be obtained in the form of a film by separating the polyimide molded product film from the base material.

In the case of obtaining a polyimide molded article using a mold, a predetermined amount of the polyamic acid composition (a) or the polyimide composition (B) is injected into the mold (particularly preferably, the mold is rotated), and then dried under the same temperature and time as those of molding conditions of a film or the like, thereby obtaining a molded article.

Examples

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

[ Synthesis of monomer ]

(Synthesis example 1 Synthesis of tetracarboxylic dianhydride having steroid Structure)

To a dry 10-liter separable flask (reaction vessel), 405g (1.0 mole) of 3, 6-cholestanol diol and 463.26g (2.2 moles) of chlorinated trimellitic anhydride were added and dissolved in 5000g of tetrahydrofuran. Then, 174.02g (2.2 mol) of pyridine was added dropwise to the reaction vessel while stirring the mixture in an ice bath. After completion of the dropwise addition, the reaction solution was stirred at room temperature (25 ℃ C.) for 5 hours. A precipitate was obtained from the contents. After the precipitate was filtered out, a large amount of the reaction solution was added to water, and the precipitate was filtered out. The solid obtained was washed with water and refluxed for further 5 hours in 5000g of acetic anhydride. After the solvent component was distilled off, recrystallization was performed using methyl ethyl ketone. A white crystalline tetracarboxylic dianhydride A (hereinafter, sometimes referred to as "ChTA-A") was obtained. The ChTA-A obtained was used in the following preparation examples (examples).

The synthesized ChTA-A was measured using a proton nuclear magnetic resonance spectrometer ("JMM-A400" manufactured by JEOL Ltd.)¹H-NMR spectrum (solvent: CDCl)₃And internal standard sample: tetramethylsilane). The chemical shift values for ChTA-A are shown below.

ChTA-A：¹H-NMR(CDCl₃)δ＝0.8-2.4(44H)、5.5(2H)、6.6-7.8(6H).

Further, the infrared absorption spectrum of the synthesized ChTA-A was measured using a Fourier transform infrared spectrometer ("Nicolet iS 50" manufactured by Thermo Fisher Scientific K.K. (sample preparation method: potassium bromide tableting method). The peaks in the IR spectrum of ChTA-A are shown below.

ChTA-A：IR(cm^-1)3000-2840cm^-1、1780cm^-1

From the obtained chemical shift value and the peak of the infrared absorption spectrum, it was confirmed that ChTA-A was a tetracarboxylic dianhydride represented by the formula (E-4).

(Synthesis example 2 Synthesis of tetracarboxylic dianhydride having steroid Structure)

A reaction was carried out in the same manner as in Synthesis example 1 except that 476.67g (2.2 mol) of 4-chloroformyl-1, 2-cyclohexanedicarboxylic anhydride was used in place of 463.26g (2.2 mol) of chlorinated trimellitic anhydride to obtain white crystalline tetracarboxylic dianhydride B (hereinafter sometimes referred to as ChTA-B). The obtained ChTA-B was used in the following preparation examples (examples).

Determination of ChTA-B in the same manner as ChTA-A¹According to the H-NMR spectrum and the infrared absorption spectrum, it was confirmed that ChTA-B was a tetracarboxylic dianhydride represented by the formula (E-5) from the obtained chemical shift value and the peak of the infrared absorption spectrum.

[ Synthesis of Polyamic acid and preparation of Polyamic acid composition ]

Preparation example 1 Polyamic acid PAA-1 and Polyamic acid composition PAA-1

A reaction solution was prepared by dissolving 71.28g (0.097 mol) of ChTA-A obtained in Synthesis example 1 and 20.04g (0.1 mol) of 4, 4' -diaminodiphenyl ether in 365.32g (corresponding to 20% of solid content) of N-methylpyrrolidone (hereinafter referred to as NMP) under a nitrogen stream. Then, the reaction solution was held at 60 ℃ for 24 hours to carry out polymerization. A solution of polyamic acid PAA-1 was obtained. Then, NMP was added to the obtained solution, and the solid content was adjusted to 10% by weight, to obtain a polyamic acid composition PAA-1 having a repeating unit represented by the formula (I-2).

The obtained polyamic acid composition PAA-1 was used in examples 1 to 3. The ingredients used in the preparation examples and the ingredients in the composition are shown in table 1.

The ingredients used in preparation example 1 and the ingredients in the composition are shown in table 1. In table 1, PAA denotes polyamic acid and PI denotes polyimide. ChTAH-A represents the tetracarboxylic dianhydride Compound A (molecular weight: 734.87) synthesized in Synthesis example 1. ChTAH-B represents the tetracarboxylic dianhydride compound B (molecular weight 747.19) synthesized in Synthesis example 2. ODA represents 4, 4' -diaminodiphenyl ether (molecular weight 200.4). PDA stands for p-phenylenediamine (molecular weight 108.12). NMP stands for N-methylpyrrolidone. These expressions are also the same in tables 2 to 5.

Preparation example 3 Polyamic acid PAA-2 and Polyamic acid composition PAA-2

Polyamic acid PAA-2 and Polyamic acid composition PAA-2 were obtained in the same manner as in preparation example 1, except that the tetracarboxylic acid compound was changed from 71.28g (0.097 mol) of ChTA-A to 72.48g (0.097 mol) of ChTA-B obtained in Synthesis example 2, and the NMP mass was changed from 365.32g to 370.07 g.

Determination of Polyamic acid PAA-2 in the same manner as Polyamic acid PAA-1¹It was confirmed from the H-NMR spectrum and the infrared absorption spectrum that the polyamic acid PAA-2 was a polyamic acid having a repeating unit represented by the formula (II-2) based on the obtained chemical shift value and the peak of the infrared absorption spectrum.

The obtained polyamic acid composition PAA-2 was used in examples 7 to 9. Table 1 shows the ingredients used in preparation example 3 and the ingredients in the composition.

(preparation examples 5, 7, 9, 11, 13, 15, 17, 19: Polyamic acid PAA-3 to 10 and Polyamic acid compositions PAA-3 to 10)

Polyamic acids PAA-3 to 10 and polyamic acid compositions PAA-3 to 10 were obtained according to preparation example 1, except that the type and amount of tetracarboxylic dianhydride added, the type and amount of diamine compound added, the type and amount of solvent added, and the amount of solvent added were changed as shown in tables 1 and 2.

Was measured in the same manner as Polyamic acid PAA-1 of preparation example 1¹H-NMR spectrum and infrared absorption spectrum. As a result, it was confirmed that the polyamic acids PAA-3 to PAA-6 and PAA-8 to PAA-10 are polyamic acids comprising a repeating unit represented by the formula (I-2). And it was confirmed that polyamic acid PAA-7 was a polyamic acid comprising a repeating unit represented by the formula (I-3). It was confirmed that polyamic acid PAA-8 further contains a repeating unit derived from 1,2,3, 4-cyclobutanetetracarboxylic acid in addition to the repeating unit represented by formula (I-2). It was confirmed that polyamic acid PAA-9 further contains a repeating unit represented by the formula (I-3) in addition to the repeating unit represented by the formula (I-2).

Each of the obtained polyamic acid compositions PAA-3 to 10 was used in examples. The ingredients used in the preparation and the ingredients in the composition are shown in tables 1 and 2.

In Table 2, PMDA represents pyromellitic anhydride (molecular weight: 218.12). CHDA represents 1,2,3, 4-cyclobutanetetracarboxylic dianhydride (molecular weight 196.11).

Preparation example 21 Polyamic acid PAA-11 and Polyamic acid composition PAA-11

Polyamic acid PAA-11 and Polyamic acid composition PAA-11 were obtained as in preparation example 1, except that the tetracarboxylic acid compound was changed from 71.28g (0.097 mol) of ChTA-A to 21.16g (0.097 mol) of pyromellitic anhydride (PMDA) having no steroid structure.

Each of the obtained polyamic acid compositions PAA-11 was used in comparative examples. The ingredients used in the preparation and the ingredients in the composition are shown in table 2.

Preparation example 23 Polyamic acid PAA-12 and Polyamic acid composition PAA-12 having no steroid Structure

Polyamic acid PAA-12 and Polyamic acid composition PAA-12 were obtained as in preparation example 1, except that the amount of the tetracarboxylic acid compound was changed from 71.28g (0.097 mol) of ChTA-A to 19.61g (0.1 mol) of 1,2,3, 4-cyclobutanetetracarboxylic dianhydride (CHDA) having no steroid structure, and the amount of NMP was changed from 365.32g to 158.52 g.

Each of the obtained polyamic acid compositions PAA-12 was used in comparative examples. The ingredients used in the preparation and the ingredients in the composition are shown in table 2.

[ Synthesis of polyimide and preparation of polyimide composition ]

Preparation example 2 polyimide PI-1 and polyimide composition PI-1

A polyamic acid composition PAA-1 was additionally prepared according to preparation example 1. 456.65g (corresponding to 10% of solid content) of NMP was added to polyamic acid composition PAA-1, and 15.84g (0.2 mol) of pyridine as a catalyst and 20.43g (0.2 mol) of acetic anhydride as a dehydrating agent were further added to prepare a reaction solution. The reaction mixture was kept at 100 ℃ for 6 hours under a nitrogen stream to effect imidization. A solution of polyimide PI-1 was obtained. After the reaction, pyridine, acetic anhydride and acetic acid were distilled off at a temperature of 100 ℃ and a pressure of 10mmHg in the reaction vessel. Thereafter, NMP was added to the reaction vessel and adjusted to 10% by weight of solid content to obtain a polyimide composition PI-1 containing a polyimide having a repeating unit represented by the formula (V-2). The polyimide composition PI-1 thus obtained was used in examples 4 to 6.

Preparation example 4 polyimide PI-2 and polyimide composition PI-2

Polyimide PI-2 and polyimide composition PI-2 were obtained according to preparation example 2, except for the following modifications. Polyamic acid PAA-1 additionally prepared according to preparation example 1 was changed to polyamic acid composition PAA-2 additionally prepared according to preparation example 3. The mass of NMP was changed from 456.65g (corresponding to 10% of solid content) to 462.59g (corresponding to 10% of solid content). 15.84g (0.2 mol) of pyridine and 20.43g (0.2 mol) of acetic anhydride were changed to 15.84g (0.2 mol) of pyridine and 20.43g (0.2 mol) of acetic anhydride.

Determination of polyimide PI-2 in the same manner as polyimide PI-1¹From the obtained chemical shift value and the peak of the infrared absorption spectrum, it was confirmed from the H-NMR spectrum and the infrared absorption spectrum that polyimide PI-2 was a polyimide having a repeating unit represented by the formula (VI-2).

The polyimide composition PI-2 thus obtained was used in examples 10 to 12. Table 1 shows the ingredients used in preparation example 4 and the ingredients in the composition.

(preparation examples 6, 8, 10, 12, 14, 16, 18 and 20: polyimide PI-3 to 10 and polyimide compositions PI-3 to 10)

Polyimide PI-3-10 and polyimide PI-3-10 were obtained according to preparation example 2, except that the polyamic acid composition PAA-1 obtained in preparation example 1 was changed to the polyamic acid compositions PAA-3-10 obtained in preparation examples 5, 7, 9, 11, 13, 15, 17, and 19, respectively.

Measured in the same manner as in PI-1 polyimide acid of preparation example 2¹H-NMR spectrum and infrared absorption spectrum. As a result, it was found that polyimide acids PI-3 to PI-6 and PI-8 to PI-10 contain a repeating unit represented by the formula (V-2). It was confirmed that polyimide PI-7 contained the repeating unit represented by the formula (V-3). It was confirmed that polyimide PI-8 further contained a repeating unit derived from 1,2,3, 4-cyclobutanetetracarboxylic acid in addition to the repeating unit represented by the formula (V-2). It was confirmed that polyimide PI-9 contained the repeating unit represented by the formula (V-3) in addition to the repeating unit represented by the formula (V-2).

Each of the polyimide compositions obtained was used in examples. The ingredients used in the preparation and the ingredients in the composition are shown in tables 1 and 2.

Preparation example 22 polyimide PI-11 and polyimide composition PI-11

Polyimide PI-11 and polyimide composition PI-11 were obtained according to preparation example 2, respectively, except that polyamic acid composition PAA-1 obtained in preparation example 1 was changed to polyamic acid composition PAA-11 obtained in preparation example 21. The polyimide composition thus obtained precipitates the polyimide thus formed.

Preparation example 24 polyimide PI-12 having no steroid Structure and polyimide composition PI-12

Polyamic acid composition PAA-12 was additionally prepared according to preparation example 23. Thereafter, a reaction was carried out in accordance with preparation example 2 except that 198.15g (corresponding to 10% of solid content) of NMP, 15.84g (0.2 mol) of pyridine and 20.43g (0.2 mol) of acetic anhydride were used, and the resulting polyimide resin was precipitated.

[ production of polyimide molded article ]

Example 1 production of polyimide film (polyimide molded article) PAA-1

The polyamic acid composition PAA-1 was coated on a Pyrex (Pyrex) glass plate using an applicator (applicator) to a coating thickness of 500 μm. After drying on a hot plate at 100 ℃ for 10 minutes, firing was carried out in an oven at 250 ℃ for 30 minutes. The thickness of the obtained polyimide film was 50 μm and was uniform and free of defects. The physical properties of the film were measured by the following methods. The results are shown in Table 3.

[ measuring method and evaluation method ]

(determination of solubility of Polyamic acid)

The prepared polyamic acid solution was added to methanol to reprecipitate a polyamic acid resin. After filtration through a G3 glass filter, the sample was dried at 30 ℃ under a reduced pressure of 10mmHg for 24 hours to obtain a polyamic acid resin sample.

Then, a predetermined amount of polyamic acid resin sample was weighed in a sample bottle, and a good solvent/poor solvent mixture was added so that the solid content became 10 wt%, and the mixture was stirred with a rotor stirrer (waverotor) for 24 hours to be dissolved. NMP was used as a good solvent, and butyl cellosolve was used as a poor solvent.

The appearance of the obtained mixed solution was visually observed to confirm whether or not the resin was precipitated. The solubility and dispersibility of the polyamic acid were evaluated based on the following evaluation criteria, based on the results of visual observation. And judging that A and B are dissolved or dispersed. The results of solubility are shown in Table 6.

(evaluation criteria)

A (very good): the appearance is the same as that of the mixed solvent alone

B (good): slightly turbid compared with the case of only the mixed solvent

C (poor): precipitation of polyamic acid was observed

The mixed solvent in the evaluation standard is a mixed solvent composed of only a good solvent and a poor solvent.

(measurement of transmittance and evaluation of transparency)

The transmittance at 550nm of the polyimide film was measured by a visible light spectrophotometer (absorbance 550 nm). The measurement results are shown in table 3.

Further, from the obtained transmittance, the transparency of the polyimide film was evaluated based on the following evaluation criteria. The evaluation results are shown in table 3. The polyimide film having the evaluation result of a or B, that is, having a transmittance of 85% or more was evaluated as a pass.

(evaluation criteria for transparency)

A (very good): the transmittance is more than 95%

B (good): the transmittance is more than 85% and less than 95%

C (poor): the transmittance is less than 85 percent

The transmittance of the polyimide film PAA-1 was 98.0%, and the evaluation result was A, which was extremely transparent.

(measurement of Pencil hardness and evaluation of mechanical Strength)

The pencil hardness of the polyimide film was measured according to JIS K5400. The measurement results are shown in table 3.

Further, from the obtained pencil hardness, the mechanical strength of the polyimide film was evaluated based on the following evaluation criteria. The evaluation results are shown in table 3. The polyimide film having a pencil hardness of H or more (more specifically, any of H, 2H, 3H, and the like) as the evaluation result of a or B was evaluated as a pass.

(evaluation criteria for mechanical Strength)

A (very good): the pencil hardness is 3H or more (more specifically, any of 3H, 4H, 6H, and the like).

B (good): the pencil hardness is H or 2H.

C (poor): the pencil hardness is HB or less (more specifically, any of HB, B, 2B, 3B, etc.).

The polyimide film PAA-1 had a pencil hardness of 3H and the evaluation result was A.

(evaluation of physical Properties (durability) of film after ultraviolet ray treatment)

The polyimide film was subjected to ultraviolet treatment. Specifically, the polyimide film was irradiated with ultraviolet light at 1.5kV for 10 minutes using an ultraviolet irradiation apparatus ECS1511-U manufactured by EYE GRAPHICS. The transmittance and pencil hardness of the polyimide film after ultraviolet irradiation were measured. And the results of transmittance and pencil hardness before and after the ultraviolet treatment were compared, respectively. In the comparison of the transmittances, a difference in transmittance (transmittance before ultraviolet irradiation — transmittance after ultraviolet irradiation) was calculated. In the comparison of the pencil hardness, the change from the result of the pencil hardness before the ultraviolet irradiation was calculated (the evaluation result of the pencil hardness was lowered by several steps: for example, when changing from HB to B, it was evaluated as being lowered by one step). From the comparison results, the durability of the polyimide film was evaluated based on the following evaluation criteria. The evaluation results are shown in table 3.

(evaluation criteria for durability)

A (very good): the difference in transmittance was less than 1, and the change in the result with respect to pencil hardness was on the order of 0

B (good): the difference in transmittance is 1 or more and less than 7 or/and the change in the result with respect to pencil hardness is on the order of 0

C (poor): the difference in transmittance is 7 or more and/or the change in the result with respect to pencil hardness is 0 or more steps

The transmittance of the polyimide film PAA-1 after ultraviolet irradiation was 97.8%, and the pencil hardness was 3H. Therefore, the difference in transmittance between the polyimide film PAA-1 before and after the ultraviolet irradiation was 0.2%, the change in pencil hardness was 0-order, and the durability was evaluated as A. That is, almost no change occurred compared to before the ultraviolet irradiation.

(examples 2 to 24, comparative examples 1 to 8 preparation of polyimide films (polyimide molded articles) 2 to 24 and C1 to C8)

Polyimide films were produced in accordance with example 1, except that the kinds and firing conditions of the polyamic acid compositions and polyimide compositions described in tables 3 to 5 were changed. The obtained polyimide film was evaluated for transmittance, mechanical strength and durability. The results obtained are shown in tables 3 to 5.

In comparative examples 7 to 8, polyimide deposition occurred in the polyimide compositions PI-11 to 12, and therefore, no polyimide film could be produced and no evaluation could be made.

[ Table 6]

As shown in Table 6, with respect to polyamic acid PAA-1, no change in solubility was observed even when the weight ratio of the good solvent to the poor solvent (NMP: butyl cellosolve) in the mixed solvent was changed. On the other hand, with respect to polyamic acid PAA-11, as the ratio of the poor solvent in the mixed solvent increased, the evaluation result was changed from A to C, and it was confirmed that the solubility decreased. Therefore, it was confirmed that polyamic acid PAA-1 was soluble in a solvent having a higher fraction of poor solvent than polyamic acid PAA-11.

As shown in tables 1 to 4, in examples 1 to 24, polyamic acid compositions PAA-1 to 9 were formed from polyamic acids PAA-1 to 9 each having a repeating unit represented by formula (A) and a solvent. The polyamic acids PAA-1 to PAA-9 are dissolved or dispersed in the solvent.

The polyimide compositions PI-1 to 9 are formed from a solvent and a polyimide PI-1 to 9 containing a repeating unit represented by the formula (B). Polyimide PI-1 to 9 is dissolved or dispersed in the solvent.

As shown in tables 3 to 4, in examples 1 to 24, polyimide films 1 to 24 were formed from either of polyamide acid compositions PAA-1 to 9 and polyimide compositions PI-1 to 9. The polyimide films 1 to 24 were evaluated for transmittance, mechanical strength and durability as a (very good) or B (good). That is, the polyimide films 1 to 24 have high transmittance and pencil hardness, and the transmittance of the films hardly decreases even after ultraviolet irradiation, and the pencil hardness maintains almost the original hardness, and has excellent transmittance, mechanical strength, and durability.

As shown in tables 2 and 5, in comparative examples 1 to 6, polyamic acid compositions 11 to 12 were formed from polyamic acids PAA-11 to 12 and a solvent. The polyamic acids PAA-11 to 12 do not contain a repeating unit represented by the formula (A).

In comparative examples 7 to 8, polyimide compositions PI-11 to 12 were formed from polyimide compositions PI-11 to 12 and a solvent. The polyimides PI-11 to 12 do not contain a repeating unit represented by the formula (B). Polyimide compositions PI-11 to 12 were precipitated and were not dissolved or dispersed in a solvent.

As shown in Table 5, in comparative examples 1 to 6, the polyimide films C1 to C6 were formed from either of the polyamic acid compositions PAA-11 and PAA-12. The polyimide films C1 to C6 had at least one C (difference) in the results of evaluation of transmittance, mechanical strength, and durability. That is, the polyimide films C1 to C6 exhibit at least: low transmittance, low mechanical strength, and at least one of a decrease in transmittance and a decrease in mechanical strength after ultraviolet irradiation. Therefore, the polyimide films C1 to C6 cannot have excellent transmittance, mechanical strength, and durability at the same time.

In comparative examples 7 to 8, polyimide films could not be produced from the polyimide compositions because polyimide PI-11 to 12 was precipitated as described above. Further, the evaluation of the polyimide film was not possible.

As can be seen, the polyimides of examples 1 to 24 have excellent transmittance, mechanical strength and durability in comparison with the polyimide films of comparative examples 1 to 6.