JP5888472B2 - Composition containing polyimide precursor and / or polyimide, and polyimide film - Google Patents

Description

  The present invention includes a polyimide precursor and / or a polyimide composition having a specific partial structure, a polyimide precursor composition that suppresses whitening of the film when forming a film, a specific partial structure, heat resistance, The present invention relates to a polyimide and a polyimide film excellent in transmittance, low linear expansion coefficient and low retardation.

  In recent years, in the fields of electric, electronic parts, transportation equipment, space, aircraft, and the like, there has been a demand for thinner and lighter devices and more flexible devices. In these devices, electronic elements such as thin transistors and transparent electrodes are formed on a glass substrate. By changing this glass substrate to a plastic material, the panel itself can be made flexible, thin, and lightweight. It is done.

In such a device manufacturing process, there is a process that becomes high temperature, and thus a high heat resistance is required for the device substrate. Therefore, development of polyimide materials as one of high heat-resistant plastics has been performed. In addition, when the dimensional change in the heating process or the like is large in the device substrate, it causes breakage and deformation of members such as electronic elements and color filters, and the quality stability is deteriorated.
In addition to heat resistance, polyimide materials that are excellent in electrical insulation, wear resistance, chemical resistance, mechanical properties, and the like have been developed.

  Patent Document 1 mentions a polyimide material that has heat resistance and little dimensional change (small linear expansion coefficient). Patent Document 2 proposes an amideimide material having an amide bond.

Japanese Unexamined Patent Publication No. 2012-144603 Japanese Unexamined Patent Publication No. 2013-028688

However, as proposed in Patent Document 1, when the monomer constituting the polyimide is only an aromatic compound, the in-plane orientation is strong, the retardation is high, and a phase difference is generated. If a material that generates such a phase difference is used, for example, the front view of the display or the visual field in an oblique direction tends to deteriorate.
Moreover, when it has an amide bond like the amide imide material proposed by patent document 2, since an amide bond has high water absorption and solvent affinity, it exists in the tendency for the hydrolyzability of the polyimide resin obtained to become high. .
As described above, no material has been proposed that simultaneously satisfies heat resistance, transmittance, low linear expansion coefficient, and low retardation, which are characteristics necessary for application to device materials.

  The present invention has been accomplished in view of the above problems, and provides a polyimide material excellent in heat resistance, transmittance, low linear expansion coefficient, and low retardation.

The present invention has the following configuration.
[1] A polyimide film containing a tetracarboxylic acid residue and a diamine residue, wherein at least one of the tetracarboxylic acid residue and the diamine residue has a bent portion, and the linear expansion coefficient is 60 ppm / K or less And the retardation is 200 nm or less, The polyimide film characterized by the above-mentioned.
[2] The polyimide film according to [1], wherein a yellow index when the film thickness is 10 μm is −10 or more and 20 or less.
[3] A composition containing at least one of a polyimide precursor and a polyimide, wherein the polyimide precursor and polyimide contain a tetracarboxylic acid residue and a diamine residue, and the tetracarboxylic acid residue is represented by the following formula: A partial structure represented by (1 ′), a partial structure represented by the following formula (2), and a partial structure represented by the following formula (4 ′), wherein the diamine residue is represented by the following formula (5): A composition having a partial structure represented, wherein at least one of the tetracarboxylic acid residue and the diamine residue has a bent portion.

However, the symbol in a formula represents the following meaning.
X ² is a direct bond, a bond having a secondary or tertiary carbon atom, or an ether bond.
R ³ and R ⁴ are each independently a functional group selected from the group consisting of an alkyl group, an alkoxy group, an amino group, and a hydroxyl group.

[4] The ratio of the tetracarboxylic acid residue having the partial structure represented by the formula (4 ′) in the tetracarboxylic acid residue is 2 mol% or more and 95 mol% or less. Composition.
[5] A tetracarboxylic acid residue having a partial structure represented by the formula (1 ′) and a tetracarboxylic acid residue having a partial structure represented by the formula (2) in the tetracarboxylic acid residue. The composition according to the above [3] or [4], wherein the sum ratio is 5 mol% or more and 95 mol% or less.
[6] The method according to any one of [3] to [5], wherein a ratio of the bent portion to a sum of the tetracarboxylic acid residue and the diamine residue is 0.1 mol% or more and 150 mol% or less. Composition.

  According to the present invention, it is possible to provide a polyimide precursor and / or a polyimide composition, a polyimide and a polyimide film which are excellent in heat resistance, transmittance, low linear expansion coefficient and low retardation.

Embodiments of the present invention will be described in detail below, but the objects and methods exemplified below are examples (representative examples) of embodiments of the present invention, and the present invention is not deviated from the gist thereof. It is not limited to these contents.
Here, “weight%” and “mass%” are synonymous.

[Composition]
The composition of the present invention is a composition containing at least one of a polyimide precursor and a polyimide, and the polyimide precursor and / or polyimide contains a tetracarboxylic acid residue and a diamine residue, and the tetracarboxylic acid The acid residue has a partial structure selected from one or more from group I shown below and a partial structure selected from one or more from group II shown below, wherein the diamine residue is represented by the following formula (5): It is a composition characterized by having the partial structure represented by these.

However, the symbol in a formula represents the following meaning.
X represents a direct bond, an alkylene group, a carbonyl group, an ether bond or a sulfonyl group.
n and m each independently represent 0 or 1.
R ¹ and R ² each independently represents an alkylene group, an alkenylene group or an aromatic ring. R ¹ and R ² may be bonded to each other to form a ring.
Y represents a direct bond or a divalent organic group.
R ³ and R ⁴ each independently represents an alkyl group, an alkoxy group, an amino group or a hydroxyl group.

The tetracarboxylic acid residue has a partial structure selected from one or more from group I and a partial structure selected from one or more from group II, and the diamine residue has a partial structure represented by formula (5) The following is estimated as a reason for having the effect of the present invention.
By having the tetracarboxylic acid residue selected from Group I and the diamine residue represented by the formula (5), the effects of improving heat resistance and mechanical properties and lowering the linear expansion coefficient can be obtained. However, when only the aromatic ring compound is used, as described above, the in-plane orientation tends to be strong and the retardation tends to be high, but by having a tetracarboxylic acid residue selected from Group II, these effects can be achieved. It is possible to control retardation while obtaining. Further, by having a tetracarboxylic acid residue selected from Group II, higher transmittance can be obtained, and in addition, the effects of improving the flexibility of the molded product can be obtained with a low refractive index, solubility in organic solvents. It is guessed.
In the present invention, the tetracarboxylic acid residue represents a tetravalent group derived from tetracarboxylic dianhydride. Moreover, in this invention, a diamine residue represents the bivalent group induced | guided | derived from the diamine compound or the diisocyanate compound.

In the composition according to the present invention, the partial structure selected from the group I is a partial structure represented by the following formula (1 ′) and a partial structure represented by the formula (2), and is selected from the group II The partial structure represented by the following formula (4 ′) and the partial structure of the diamine residue being the partial structure represented by the following formula (5) balance the linear expansion coefficient and the optical characteristics. It is preferable because it is easy to remove, and it is more preferable that at least one of the tetracarboxylic acid residue and the diamine residue has a bending site.
Details of each partial structure and bending portion will be described later.

However, the symbol in a formula represents the following meaning.
X ² is a direct bond, a bond having a secondary or tertiary carbon atom, or an ether bond.
R ³ and R ⁴ are each independently a functional group selected from the group consisting of an alkyl group, an alkoxy group, an amino group, and a hydroxyl group.

  The composition of the present invention may contain other components in addition to the polyimide precursor and / or polyimide. For example, an imidizing agent can be added in order to further increase the imidization rate during film formation.

[Polyimide precursor and / or polyimide contained in composition]
The polyimide precursor and / or polyimide contained in the composition according to the present invention includes a tetracarboxylic acid residue and a diamine residue. The tetracarboxylic acid residue has a partial structure selected from one or more groups from group I and a partial structure selected from one or more groups from group II. The partial structure represented by formula (5) as the diamine residue If it has, it will not specifically limit. These are preferably compounds soluble in a solvent.
The composition of the present invention may have a polyimide precursor and / or a polyimide that does not have a partial structure of Group I or Group II as a tetracarboxylic acid residue. Moreover, you may have what does not have the partial structure represented by Formula (5) as a diamine residue.

In the present invention, “soluble in a solvent” means complete dissolution when a polyimide precursor and / or polyimide is dissolved at 0.5% by mass at room temperature (25 ° C.) in a solvent constituting the composition. To do.
The concentration for complete dissolution is usually 0.5% by mass or more, preferably 1% by mass or more, and more preferably 10% by mass or more.
Examples of the solvent constituting the composition include a solvent used for obtaining a polyimide precursor and polyimide contained in the composition of the present invention described later, a solvent used for reprecipitation, and the like.

The concentration of the polyimide precursor and / or polyimide in the composition can be appropriately confirmed using a conventionally known method. For example, the solvent of the composition can be obtained by distillation using a method such as drying under reduced pressure, and the mass ratio before and after the distillation.
When the concentration of the composition is less than 0.5% by mass, the composition can be concentrated using a method such as distilling off the solvent under reduced pressure to determine whether or not the composition is soluble in the solvent. When the concentration of the composition is high, the concentration can be made 0.5 mass% by diluting with the solvent of the composition. When the solvent of the composition is unknown, for example, amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone; aprotic solvents such as dimethyl sulfoxide; anisole It can be diluted with aromatic solvents such as cresol, xylene and toluene, glycol solvents such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether and propylene glycol monomethyl ether acetate. .

Examples of the tetracarboxylic acid residue include partial structures of Group I and Group II. The tetracarboxylic acid residue is not particularly limited as long as it has a partial structure selected from one or more groups from group I and a partial structure selected from one or more groups from group II. For example, it has a plurality of partial structures from group I. And may have a plurality of partial structures represented by the formula (1).
In the group I, since the effect of lowering the linear expansion coefficient is high, it preferably has a partial structure represented by the formula (1), and is represented by the partial structure represented by the formula (1) and the formula (2). It is more preferable to have both of the partial structures to be obtained because the heat resistance, the mechanical properties, and the linear expansion coefficient tend to be obtained.
Further, in the group II, it is preferable to have a partial structure represented by the formula (4) in order to improve optical characteristics.

  The ratio of the tetracarboxylic acid residues having a partial structure selected from each group of Group I and Group II among tetracarboxylic acid residues contained in the composition of the present invention is not particularly limited, but is usually 10 mol. % Or more, preferably 30 mol% or more, more preferably 50 mol% or more. By being in this range, it is possible to obtain a polyimide precursor and / or a polyimide composition having good optical properties and a low linear expansion coefficient.

The ratio of the tetracarboxylic acid residue having a partial structure selected from Group I and the tetracarboxylic acid residue having a moiety selected from Group II is not particularly limited.
Of the tetracarboxylic acid residues contained in the composition of the present invention, the proportion of the tetracarboxylic acid residues having a partial structure selected from Group I is usually 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, usually 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less. By being in this range, it is possible to obtain a polyimide precursor and / or a polyimide composition having good optical properties and a low linear expansion coefficient.
The ratio of the tetracarboxylic acid residue having a partial structure selected from Group I and the tetracarboxylic acid residue having a partial structure selected from Group II is not particularly limited. It is 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, and is usually 500 mol% or less, preferably 300 mol% or less, more preferably 200 mol% or less, and even more preferably 150 mol% or less.

  Among the tetracarboxylic acid residues contained in the composition of the present invention, a tetracarboxylic acid residue having a partial structure represented by the formula (1 ′) and a tetracarboxylic acid having a partial structure represented by the formula (2) The ratio of the sum of the residue and the tetracarboxylic acid residue having the partial structure represented by the formula (4 ′) is not particularly limited, but is usually 10 mol% or more, preferably 30 mol% or more, more preferably 50 mol%. That's it. By being in this range, it is possible to obtain a polyimide precursor and / or a polyimide composition having good optical properties and a low linear expansion coefficient.

A tetracarboxylic acid residue having a partial structure represented by the formula (1 ′), a tetracarboxylic acid residue having a partial structure represented by the formula (2), and a partial structure represented by the formula (4 ′) The ratio with the tetracarboxylic acid residue is not particularly limited.
Among the tetracarboxylic acid residues contained in the composition of the present invention, a tetracarboxylic acid residue having a partial structure represented by the formula (1 ′) and a tetracarboxylic acid having a partial structure represented by the formula (2) The ratio of the sum occupied by the residues is usually 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, usually 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less. By being in this range, it is possible to obtain a polyimide precursor and / or a polyimide composition having good optical properties and a low linear expansion coefficient. Moreover, in the polyimide film obtained from the composition, the absorption near 308 nm and 355 nm used for laser processing increases, and it can be compatible with laser processing.

  A tetracarboxylic acid residue having a partial structure represented by the formula (1 ′), a tetracarboxylic acid residue having a partial structure represented by the formula (2), and a partial structure represented by the formula (4 ′) The ratio with the tetracarboxylic acid residue is not particularly limited, but the tetracarboxylic acid residue having the partial structure represented by the formula (1 ′) and the tetracarboxylic acid residue having the partial structure represented by the formula (2) The proportion of the tetracarboxylic acid residue having a partial structure represented by the formula (4 ′) relative to the sum of the groups, is usually 5 mol% or more, preferably 10 mol% or more, more preferably 15 mol% or more, and usually 500 mol% or less. , Preferably 300 mol% or less, more preferably 200 mol% or less, and even more preferably 150 mol% or less. By being in this range, it is possible to obtain a polyimide precursor and / or a polyimide composition having good optical properties and a low linear expansion coefficient.

  The proportion of the tetracarboxylic acid residue having a partial structure represented by the formula (4 ′) in the tetracarboxylic acid residue contained in the composition of the present invention is usually 2 mol% or more, preferably 5 mol% or more, More preferably, it is 8 mol% or more, usually 95 mol% or less, preferably 90 mol% or less, more preferably 85 mol% or less. By being in this range, it is possible to obtain a polyimide precursor and / or a polyimide composition having good optical properties and a low linear expansion coefficient.

  The ratio of the tetracarboxylic acid residue having a partial structure represented by the formula (2) to the tetracarboxylic acid residue having a partial structure represented by the formula (1 ′) is not particularly limited, but is usually 0.5 mol. % Or more, preferably 1 mol% or more, more preferably 3 mol% or more, and usually 500 mol% or less, preferably 400 mol% or less, more preferably 300 mol% or less. By being in this range, it is possible to obtain a polyimide precursor and / or a polyimide composition having good optical properties and a low linear expansion coefficient.

  A tetracarboxylic acid residue having a partial structure represented by the formula (1 ′) in a tetracarboxylic acid residue having a partial structure represented by the formula (2) and a partial structure represented by the formula (2) The ratio of the tetracarboxylic acid residue to the sum is not particularly limited, but is usually 1 mol% or more, preferably 3 mol% or more, more preferably 5 mol% or more, and usually 95 mol% or less, preferably 90 mol% or less, more preferably It is 85 mol% or less. By being in this range, it is possible to obtain a polyimide precursor and / or a polyimide composition having good optical properties and a low linear expansion coefficient.

The ratio of the tetracarboxylic acid residue can be determined by analyzing the composition of the raw material monomer by NMR, solid NMR, IR, or the like. Moreover, after melt | dissolving with an alkali, it can obtain | require by gas chromatography (GC), < ¹ > H-NMR, < ¹³ > C-NMR, two-dimensional NMR, mass spectrometry, etc.

  The ratio of the diamine residue having a partial structure represented by the formula (5) in the diamine residue is not particularly limited, but is usually 0.1 mol% or more, preferably 1 mol% or more, more preferably 5 mol% or more. More preferably, it is 7 mol% or more, more preferably 20 mol% or more, further preferably 30 mol% or more, more preferably 40 mol% or more, and further preferably 50 mol% or more. Moreover, there is no upper limit in particular and 100 mol% may be sufficient. A polyimide precursor and / or a polyimide composition for obtaining a polyimide having a low linear expansion coefficient is obtained by including a specific amount or more of the diamine residue having the partial structure represented by the formula (5) in the diamine residue. be able to.

  The amount of the diamine compound for inducing the diamine residue is usually 0.7 mol or more, preferably 0.8 mol or more, usually 1.3 mol or less, preferably 1.2 mol or less, relative to 1 mol of tetracarboxylic dianhydride. It is. By setting the amount of the diamine compound within this range, a polyimide precursor and / or a polyimide having an appropriate molecular weight can be obtained.

(Group I and Group II)
Group I: The following formulas (1) and (2) are shown.

[In Formula (1),
X represents a direct bond, an alkylene group, a carbonyl group, an ether bond or a sulfonyl group. ]

Group II: The following formulas (3) and (4) are shown.

[In Formula (3),
n and m each independently represent 0 or 1,
R ¹ and R ² each independently represents an alkylene group, an alkenylene group or an aromatic ring.
R ¹ and R ² may be different or the same, and may form a ring. ]

[In Formula (4),
Y represents a direct bond or a divalent organic group. ]

(Group I)
(Tetracarboxylic acid residue having a partial structure represented by formula (1))
In the formula (1), X represents a direct bond, an alkylene group, a carbonyl group, an ether bond or a sulfonyl group. Among these, X is preferably a direct bond, a carbonyl group or a sulfonyl group, and more preferably a direct bond, since the effect of lowering the linear expansion coefficient is high.

  The alkylene group is not particularly limited, but preferably has 1 or more carbon atoms, more preferably 2 or more. On the other hand, it is preferably 8 or less, and more preferably 5 or less. Moreover, the said alkylene group may have a substituent, for example, an amino group, a hydroxyl group, a halogen atom, etc. are mentioned.

  The tetracarboxylic acid residue having a partial structure represented by the formula (1) is not particularly limited. For example, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,3,3 ′, 4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride and the like tetracarboxylic dianhydrides in which X is a direct bond; bis (3,4-di Carboxyphenyl) methane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, 2,3,3 ′, 4′-tetracarboxyphenylmethane dianhydride, 2,2-bis (3,4 -Dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2,2- (2,3,3 ', 4'-tetracarboxyphenyl) propane Anhydride, 2, 2 Tetracarboxylic dianhydrides in which X is an alkylene group, such as bis (3,4-dicarboxyphenyl) 1,1,1,3,3,3-hexafluoropropane dianhydride; 3,3 ′, 4, X of 4′-benzophenone tetracarboxylic dianhydride, 2,2 ′, 3,3′-benzophenone tetracarboxylic dianhydride, 2,3,3 ′, 4′-benzophenone tetracarboxylic dianhydride, etc. Tetracarboxylic dianhydride which is a carbonyl group; tetracarboxylic whose X is an ether bond such as 4,4′-oxydiphthalic anhydride, 3,4′-oxydiphthalic anhydride, 3,3′-oxydiphthalic anhydride Acid dianhydride; 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, 2,3,3 ′, 4′-diphenylsulfonetetracarboxylic dianhydride, 2,2 ′, 3 It includes tetracarboxylic acid residue derived from the tetracarboxylic dianhydride, such as; X such 3'-diphenylsulfone tetracarboxylic dianhydride dianhydride sulfonyl group.

  The partial structure represented by the formula (1) of the tetracarboxylic acid residue is the partial structure represented by the following formula (1 ′), which improves the heat resistance and mechanical properties and lowers the linear expansion coefficient. Is preferable because it tends to be obtained.

In formula (1 ′), X ² is a direct bond, a bond having a secondary or tertiary carbon atom, or an ether bond, and among these, a direct bond is preferable because mechanical properties are improved. Moreover, in the polyimide film obtained from the composition, absorption near 308 nm and 355 nm used for laser processing is increased, which is preferable because it can be applied to laser processing.
The bond having a secondary or tertiary carbon atom means that X ² is a secondary or tertiary carbon atom having 1 carbon atom. The carbon atom of X ² is linked to a hydrogen atom and / or a substituent other than being linked to the benzene ring in formula (1 ′). Examples of the substituent connected to the carbon atom of X ² include a halogen atom, a cyano group, a nitro group, and a sulfo group.

(Tetracarboxylic acid residue having a partial structure represented by formula (2))
Examples of the tetracarboxylic dianhydride that derives a tetracarboxylic acid residue having a partial structure represented by the formula (2) include pyromellitic dianhydride.

(Group II)
(Tetracarboxylic acid residue having a partial structure represented by formula (3))
In Formula (3), n and m each independently represent 0 or 1. Although not particularly limited, at least one of n and m is preferably 1 from the viewpoint of imidization reactivity. R ¹ and R ² each independently represents an alkyl group, an alkenyl group or an aromatic ring. R ¹ and R ² may be different or the same, and may form a ring. Moreover, the alkyl group, the alkenyl group, and the aromatic ring may have a substituent.
As an alkyl group and an alkenyl group, C1 or more is preferable each independently. On the other hand, 10 or less is preferable, and 8 or less is more preferable. By being in this range, the solubility in an organic solvent tends to increase.
The aromatic ring may be either a single ring or a condensed ring. Specifically, a benzene ring, a naphthalene ring, an anthracene ring, etc. are mentioned. In particular, a benzene ring is preferable because the solubility in an organic solvent tends to be high.

The tetracarboxylic acid residue having a partial structure represented by the formula (3) is not particularly limited. For example, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,3,4- Cyclopentanetetracarboxylic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclohexanetetracarboxylic dianhydride, bicyclo [2,2,2] oct -7-ene-2,3,4,6-tetracarboxylic dianhydride, tricyclo [6,4,0,0 ^2,7 ] dodecane-1,8: 2,7-tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutanetetracarboxylic dianhydride, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4 -Tetrahydronaphthalene-1,2-di Tetracarboxylic acid residue and the like which are derived from tetracarboxylic dianhydride such as carboxylic acid anhydride.

(Tetracarboxylic acid residue having a partial structure represented by formula (4))
Y represents a direct bond or a divalent organic group. Although it does not specifically limit as a bivalent organic group, For example, an alkylene group, a carbonyl group, an ether bond, a sulfonyl group etc. are mentioned. Among these, Y has a tendency to improve optical characteristics, and therefore, direct bonding is preferable.
The said alkylene group is synonymous with the preferable range of the alkylene group of X of Formula (1), and the substituent which you may have is also synonymous.

The tetracarboxylic acid residue having a partial structure represented by the formula (4) is not particularly limited. For example, bicyclohexane-3,3 ′, 4,4′-tetracarboxylic dianhydride, bicyclohexane-2 , 3,3 ′, 4′-tetracarboxylic dianhydride, tetracarboxylic acid derived from tetracarboxylic dianhydride such as bicyclohexane-2,2 ′, 3,3′-tetracarboxylic dianhydride Examples include residues.
Of these, tetracarboxylic acid residues derived from bicyclohexane-3,3 ′, 4,4′-tetracarboxylic dianhydride are preferred because optical properties tend to improve.

  The partial structure represented by the formula (4) of the tetracarboxylic acid residue is preferably a partial structure represented by the following formula (4 ′) because the optical properties are improved.

(Diamine residue)
Examples of the diamine residue include a partial structure represented by the formula (5).

[In Formula (5), R < ³ > and R < ⁴ > shows an alkyl group, an alkoxy group, an amino group, or a hydroxyl group each independently. ]

(Diamine residue having a partial structure represented by formula (5))
R ³ and R ⁴ each independently represents an alkyl group, an alkoxy group, an amino group, or a hydroxyl group.
The alkyl group and the alkoxy group each independently preferably have 1 or more carbon atoms. On the other hand, 10 or less is preferable, 8 or less is more preferable, and 6 or less is particularly preferable. This range is preferable because the linear expansion coefficient tends to be low.
Moreover, the alkyl group and the alkoxy group may each have a substituent. Examples of the substituent that the alkyl group may have include a halogen atom, a cyano group, a nitro group, and a sulfo group. Among these, it is preferable to have a halogen atom, and a fluorine atom is particularly preferable. Within this range, the linear expansion coefficient tends to be low.
Examples of the substituent that the alkoxy group may have include an alkyl group having 1 to 6 carbon atoms, a halogen atom, a cyano group, a nitro group, a sulfo group, and an allyl group.
Among these, R ³ and R ⁴ are preferably an alkyl group or an alkoxy group because optical characteristics and a linear expansion coefficient are improved, and an alkyl group having a halogen atom as a substituent tends to have a low linear expansion coefficient. Therefore, it is more preferable. R ³ and R ⁴ may be the same or different, but are preferably the same from the viewpoint of ease of production.

The diamine residue having a partial structure represented by the formula (5) is not particularly limited. For example, R such as 4,4′-diamino-2,2′-dimethylbiphenyl, 4,4′-diamino-2,2′-diethylbiphenyl, 4,4′-diamino-2,2′-dipropylbiphenyl, etc. Diamine compound in which ³ and R ⁴ have an alkyl group; 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl, 4,4′-diamino-2-methyl-2′-trifluoromethylbiphenyl A diamine compound in which R ³ and R ^{4 each} have a halogenated alkyl group; 4,4′-diamino-2,2′-dimethoxybiphenyl, 4,4′-diamino-2,2′-diethoxybiphenyl, an amino group 2,2 ', 4,4'-tetra-aminobiphenyl, a hydroxyl group, the diamine of having ^{R 3} and ^{R 4} are alkoxy groups such as 4,4'-diamino-2,2'-dihydroxybiphenyl with Things; the diamine residue derived from a diamine compound such like.

(A tetracarboxylic acid residue having other than the partial structure represented by Formula (1), Formula (2), Formula (3), and Formula (4), and Formula (1 ′), Formula (2), Formula (4 ') And a tetracarboxylic acid residue having other than the partial structure represented by formula (5))
As the tetracarboxylic acid residue having other than the partial structure represented by the formula (1), the formula (2), the formula (3) and the formula (4) without departing from the gist of the present invention, the aromatics shown below Tetracarboxylic acid residues derived from tetracarboxylic dianhydrides such as tetracarboxylic dianhydrides and aliphatic tetracarboxylic dianhydrides can be used.
Moreover, the composition according to the present invention has a partial structure represented by the formula (1 ′), the formula (2), the formula (4 ′) and the formula (5), a tetracarboxylic acid residue and a diamine residue. In the case where at least one of the following has a bent site, a tetracarboxylic acid residue having other than the partial structure represented by formula (1 ′), formula (2), formula (4 ′) and formula (5), Other than the tetracarboxylic acid residues derived from tetracarboxylic dianhydrides such as aromatic tetracarboxylic dianhydrides and aliphatic tetracarboxylic dianhydrides shown below and partial structures represented by formula (3) The tetracarboxylic acid residue which has is mentioned.

(Aromatic tetracarboxylic dianhydride)
Examples of the aromatic tetracarboxylic dianhydride include tetracarboxylic dianhydrides having one aromatic ring contained in the molecule such as 1,2,3,4-benzenetetracarboxylic dianhydride; 2 , 2 ′, 6,6′-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride 2,2-bis (2,3-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 2,2′-bis (trifluoromethyl) -4,4 ', 5,5'-biphenyltetracarboxylic dianhydride, 4,4'-(hexafluorotrimethylene) -diphthalic dianhydride, 4,4 '-(octafluorotetramethylene) -diphthalic dianhydride Te having two or more independent aromatic rings such as 1,3,5,6-naphthalenedicarboxylic acid dianhydride, 1,4,5,8-naphthalenedicarboxylic acid dianhydride, 2,3,6,7-naphthalenedicarboxylic acid dianhydride 3,4,9,10-perylenetetracarboxylic dianhydride, 2,3,6,7-anthracenetetracarboxylic dianhydride, 1,2,7,8-phenanthrenetetracarboxylic dianhydride, etc. And tetracarboxylic dianhydride having a condensed aromatic ring.

(Aliphatic tetracarboxylic dianhydride)
Examples of the aliphatic tetracarboxylic dianhydride include alicyclic tetracarboxylic acids such as 5- (2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride. Dianhydrides; chain aliphatic tetracarboxylic dianhydrides such as ethylenetetracarboxylic dianhydride, butanetetracarboxylic dianhydride, meso-butane-1,2,3,4-tetracarboxylic dianhydride And the like.

(Diamine residue having other than the partial structure represented by formula (5))
A diamine residue derived from a diamine compound shown below can be used as a diamine residue having a structure other than the partial structure represented by the formula (5) without departing from the gist of the present invention.

  Examples of other diamine compounds include diamine compounds having one aromatic ring contained in a molecule such as 1,4-phenylenediamine, 1,2-phenylenediamine, 1,3-phenylenediamine; -Diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 2,2-bis (4- (4-amino Phenoxy) phenyl) propane, bis (4- (4-aminophenoxy) phenyl) sulfone, bis (4- (3-aminophenoxy) phenyl) sulfone, 1,3-bis (4-aminophenoxy) neopentane, bis (4 -Amino-3-carboxyphenyl) methane, 4,4'-diaminodiphenylsulfone, 4,4'-dia Nodiphenyl sulfide, N- (4-aminophenoxy) -4-aminobenzamine, 2,2′-bis (trifluoromethyl) -4,4′-diaminobiphenyl, bis (3-aminophenyl) sulfone, norbornanediamine 4,4′-diamino-2- (trifluoromethyl) diphenyl ether, 5-trifluoromethyl-1,3-benzenediamine, 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane, 4,4′-diamino-2,2′-bis (trifluoromethyl) biphenyl, 2,2-bis [4- {4-amino-2- (trifluoromethyl) phenoxy} phenyl] hexafluoropropane, 2- Trifluoromethyl-p-phenylenediamine, 2,2-bis (3-amino-4-methylphenyl) Diamine compounds having two or more independent aromatic rings such as safluoropropane and bis (4-aminophenyl) acetylene; 4,4 ′-(9-fluorenylidene) dianiline, 2,7-diaminofluorene, 1,5- And diamine compounds having condensed aromatic rings such as diaminonaphthalene and 3,7-diamino-2,8-dimethyldibenzothiophene 5,5-dioxide.

  Among the diamine residues having other than the partial structure represented by the formula (5), it is preferable to have a diamine residue having a partial structure represented by the formula (6) in order to improve optical properties.

[In Formula (6),
Z represents a direct bond, a sulfonyl group, an alkylene group, a carbonyl group or an ether bond, and A and B each independently represent a direct bond, a divalent aromatic ring, a divalent heterocyclic ring or a phenyl ether group. ]

Among Z, a sulfonyl group, an ether bond or a carbonyl group is preferable, and a sulfonyl group is more preferable in order to further improve optical properties.
The alkylene group for Z is not particularly limited, but preferably has 1 or more carbon atoms, more preferably 2 or more. On the other hand, it is preferably 8 or less, and more preferably 5 or less.

A and B each independently represent a direct bond, a divalent aromatic ring, a divalent heterocyclic ring or a phenyl ether group. The divalent aromatic ring and the divalent heterocyclic ring may have a substituent.
Of these, phenyl ether groups are preferred because they tend to be highly soluble in solvents. A and B may be the same or different, but the same is preferable from the viewpoint of ease of production.

  Specific examples of the divalent aromatic rings A and B include a benzene ring, a naphthalene ring, and an anthracene ring. Among these, a benzene ring is preferable because the solubility in a solvent tends to be high. Specific examples of the divalent heterocycle of A and B include furan, thiophene, pyrrole, imidazole, pyridine, pyrimidine, pyrazine, oxazole, benzimidazole, and benzoxazole.

  Examples of the diamine residue having a partial structure represented by the formula (6) include 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, 3,3 Diamine compounds in which Z is a direct bond such as' -bis (4-aminophenoxy) biphenyl, 3,4'-bis (4-aminophenoxy) biphenyl; 3,3'-diaminodiphenylsulfone, 4,4'-diamino Diphenylsulfone, 3,4'-diaminodiphenylsulfone, 2,3'-diaminodiphenylsulfone, 2,4'-diaminodiphenylsulfone, bis (4- (4-aminophenoxy) phenyl) sulfone, bis (4- (3 A diamine compound in which Z is a sulfonyl group, such as -aminophenoxy) phenyl) sulfone; 2,2-bis (4- (4-amino) Enoxy) phenyl) propane, 2,2-bis (4- (3-aminophenoxy) phenyl) propane, 1,3-bis (4-aminophenoxy) neopentane, bis (4-amino-3-carboxyphenyl) methane, etc. A diamine compound wherein Z is an alkylene group; Z such as 4,4′-diaminodiphenyl ketone, 3,4′-diaminodiphenyl ketone, 2,3′-diaminodiphenyl ketone, 2,4′-diaminodiphenyl ketone, etc. Diamine compounds as groups; 3,3 ′, 4,4′-tetraaminodiphenyl ketone, 4,4′-bis (4-aminophenoxy) benzophenone, 4,4′-bis (3-aminophenoxy) benzophenone, etc. A diamine residue derived from a diamine compound such as a diamine compound in which Z is an ether bond; It is.

(Tetracarboxylic acid residue and / or diamine residue having a bent part)
In the polyimide precursor and / or polyimide in the composition of the present invention, it is preferable to have a tetracarboxylic acid residue and / or a diamine residue having a bent portion because the optical properties tend to be improved.
In the present invention, the bending portion is a bending portion in which deformation is suppressed, and a ring bond angle around the bending portion, a ring surface angle bonded to the bending portion, a tetracarboxylic acid residue such as rotation, vibration, etc. And / or those that suppress the movement of molecules containing diamine residues. Among them, those that suppress the ring coupling angle and rotational movement around the bent portion are preferable.

That is, the bent portion is preferably a trivalent or higher group that is directly bonded to the ring structure and the ring structure, and the bond angle between the ring structures is less than 180 degrees, preferably 160 degrees or less, more preferably 130 degrees. It is as follows. There is no particular lower limit, but it is usually 90 degrees or more.
The angle can be obtained by a conventionally known calculation method. For example, empirical molecular orbital methods such as Hückel method and extended Huckel method, Hartley Fock method, configuration substitution interaction method, ab initio molecular orbital methods such as multi-configuration SCF method, PPP approximation, CNDO / 2, INDO, MNDO And semi-empirical molecular orbital methods such as AM1 and PM3, molecular dynamics methods such as MM2, and density functional methods such as BLYP and B3LYP.

In the present invention, by having a bent portion, thermal vibration of the polyimide precursor and / or the entire polyimide chain is suppressed, and the linear expansion coefficient tends to be improved. Furthermore, by suppressing the interaction between the polyimide precursor and / or the polyimide chain, the optical properties such as transmittance and YI tend to be improved, and the regular orientation of the same chain is disturbed, Retardation tends to improve.
Further, entanglement of molecular chains of the polyimide precursor and / or polyimide increases, and the amount of aromatic rings in the chain increases, so that the heat resistance tends to be improved.

  The polyimide precursor and / or polyimide in the composition of the present invention may have both a tetracarboxylic acid residue and a diamine residue, which usually have a bending site, and a tetracarboxylic acid having a bending site. It may have a residue or a diamine residue. Among these, since the optical properties tend to be improved, the diamine residue preferably has a bent portion. In addition, it is preferable that the tetracarboxylic acid residue and the diamine residue have a bent portion because the optical characteristics tend to be improved.

In the present invention, a tetracarboxylic acid residue and / or diamine residue bending portion may have a plurality of bending portions, but the plurality of bending portions are preferably not connected. It exists in the tendency which can maintain and improve polymerizability by a bending part not connecting.
In the present invention, it is preferable that a cyclic structure is directly bonded to the bent portion. By directly bonding the annular structure, deformations such as a bonding angle, a surface angle of a ring bonded to a bent portion, rotation, vibration, and the like are further suppressed. The cyclic structure directly bonded to the bending site may be derived from the same tetracarboxylic acid residue / diamine residue as the bending site or may be different. When derived from the same tetracarboxylic acid residue / diamine residue as that of the bent part, the cyclic structure is a structure possessed by the tetracarboxylic acid monomer / diamine monomer. When not derived from the same tetracarboxylic acid residue / diamine residue as the bending site, the cyclic structure is a cyclic imide structure.

The tetracarboxylic acid residue having a bent portion may be a tetracarboxylic acid residue having a partial structure represented by the above formula (1), formula (2), formula (3) and formula (4), It may be a tetracarboxylic acid residue having other than the partial structure represented by formula (1), formula (2), formula (3) and formula (4).
From the viewpoint of achieving both a low linear expansion coefficient and a low retardation, the tetracarboxylic acid residue having a bent portion is preferably represented by the formula (1), the formula (2), the formula (3), and the formula (4). It is a tetracarboxylic acid residue having other than a partial structure. Furthermore, from the viewpoint of achieving both a low linear expansion coefficient and a low retardation, the tetracarboxylic acid residue having a bent portion is other than the partial structure represented by the above formula (1 ′), formula (2) and formula (4 ′). It is a tetracarboxylic acid residue having
Moreover, you may have two or more tetracarboxylic acid residues which have a bending part.
The diamine residue having a bent portion is other than the partial structure represented by the above formula (5), and may have a plurality.

  The content of the bent portion is not particularly limited, but is usually 0.1 mol% or more, preferably 0.5 mol%, more preferably 1 mol%, based on the ratio of the tetracarboxylic acid residue and the diamine residue in the composition. As mentioned above, More preferably, it is 5 mol% or more. Moreover, it is 150 mol% or less normally, Preferably it is 100 mol% or less, More preferably, it is 50 mol% or less. By being in these ranges, the optical properties are improved and the mechanical properties tend to be improved.

  As a bending part, it is preferable that the element which comprises a principal chain couple | bonded with the ring has a trivalent or more bond. Among the trivalent or higher bonds, at least one selected from a quaternary carbon atom, a hexavalent sulfur atom, a tertiary amine, and a benzene ring is preferable. In particular, the optical properties are improved when the tetracarboxylic acid and / or diamine residue having a bent portion is one in which two or more aromatic rings are bonded by a quaternary carbon atom and / or a hexavalent sulfur atom. This is preferable.

  Those having a bond of 3 or more are not particularly limited as long as they do not depart from the gist of the present invention, and examples thereof include a structure represented by the following formula (30).

In the above formula (30), Z ¹ represents a quaternary carbon atom, a hexavalent sulfur atom, a tertiary amine or a benzene ring. Y ¹ and Y ² each independently represent a cyclic structure.
As the quaternary carbon, hexafluoropropane, propane, fluorene and the like are preferable because optical characteristics are improved. As hexavalent sulfur, a sulfonyl group is preferable because optical characteristics are improved. Trimethylamine is preferred as the tertiary amine.

The cyclic structure of Y ¹ and Y ² represents an aromatic compound, an alicyclic compound, or an imide ring.
With the aromatic compound, the number of elements forming one ring is 5 or more and 8 or less, and a single ring or two rings may be condensed. Specifically, it is a benzene ring, a condensed aromatic ring or a heterocyclic ring.
The number of condensed aromatic rings is not particularly limited, but is preferably 2 or more and 5 or less because heat resistance and optical properties tend to be compatible.
The heterocyclic ring is not particularly limited, and specific examples include furan, thiophene, pyrrole, imidazole, pyridine, pyrimidine, pyrazine, oxazole, benzimidazole, benzoxazole and the like.
Examples of the substituent that the aromatic compound may have include an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an amino group, and a hydroxyl group.
The alkyl group having 1 to 6 carbon atoms and the alkoxy group having 1 to 6 carbon atoms may have a substituent.
Examples of the substituent that the alkyl group having 1 to 6 carbon atoms may have include a halogen atom and a hydroxyl group.
Examples of the substituent that the alkoxy group having 1 to 6 carbon atoms may have include a halogen atom and a hydroxyl group.

The alicyclic compound has 4 or more and 8 or less carbon atoms forming one ring, and a single ring or two rings may be condensed. Moreover, you may have an unsaturated bond in the ring.
Specific examples include cyclobutane, cyclobutadiene, cyclopentane, cyclopentaene, cyclohexane, cyclohexaene, cyclohexadiene, cycloheptane, cycloheptaene, cyclooctane, and the like.
The alicyclic compound may have a substituent, and examples of the substituent that may be included include an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and an amino group. Group, hydroxyl group and the like. The alkyl group having 1 or more and 6 or less carbon atoms and the alkoxy group having 1 or more and 6 or less carbon atoms may have a substituent, and examples of the substituent that may have may include the above-mentioned aromatic compounds. Synonymous with things.

  An imide ring is a ring having an imide bond, the number of elements forming one ring is 4 or more and 6 or less, and may be only an imide ring or may be condensed with another ring. The ring which may be condensed includes an aromatic compound which may have a substituent and an alicyclic compound which may have a substituent. The number of rings in the case of condensation is not particularly limited, but is preferably 2 or more and 4 or less because heat resistance and optical properties tend to be compatible.

  Among the structures represented by the formula (30), a site selected from the structures represented by the following formulas (31) to (35) is preferable from the viewpoint of improving optical properties.

In formula (31), R ¹⁰ and R ¹¹ each independently represents an alkyl group, an amino group or a hydroxyl group, and Y ¹ and Y ² each independently represent an aromatic hydrocarbon, an alicyclic compound or an imide ring. Represents.
The alkyl group for R ¹⁰ and R ¹¹ preferably has 1 or more carbon atoms. On the other hand, 10 or less is preferable, 8 or less is more preferable, and 6 or less is particularly preferable. This range is preferable because the linear expansion coefficient tends to be low. Moreover, the alkyl group may have a substituent. Examples of the substituent that the alkyl group may have include a halogen atom, a cyano group, a nitro group, and a sulfo group. Among these, unsubstituted or preferably having a halogen atom is preferable, and a fluorine atom is particularly preferable. Within this range, the linear expansion coefficient tends to be low.
Y ¹ and Y ² are each as Y ¹ and Y ² of Formula (30) interchangeably, examples, preferred ranges, and the substituent which may have also the same.

In formula (32), R < ¹² > -R < ¹⁵ > shows an alkyl group or a hydroxyl group each independently.
The alkyl groups of R ^{12 to} R ¹⁵ each independently preferably have 1 or more carbon atoms. On the other hand, 10 or less is preferable, 8 or less is more preferable, and 6 or less is particularly preferable. This range is preferable because the linear expansion coefficient tends to be low. Moreover, the alkyl group may have a substituent. Examples of the substituent that the alkyl group may have include a halogen atom, a cyano group, a nitro group, and a sulfo group. Among these, it is preferable to have a halogen atom, and a fluorine atom is particularly preferable. Within this range, the linear expansion coefficient tends to be low.
Y ¹ and Y ² are each as Y ¹ and Y ² of Formula (30) interchangeably, examples, preferred ranges, and the substituent which may have also the same.

Wherein (33), ^{Y 1} and ^{Y 2} are each as ^{Y 1} and ^{Y 2} of Formula (30) interchangeably, examples, preferred ranges, and the substituent which may have also the same.

In the formula (34), R ¹⁶ represents an alkyl group or an aromatic compound. Y ¹ and Y ² are each as Y ¹ and Y ² of Formula (30) interchangeably, examples, preferred ranges, and the substituent which may have also the same.
The alkyl group for R ¹⁶ preferably has 1 or more carbon atoms. On the other hand, 10 or less is preferable, 8 or less is more preferable, and 6 or less is particularly preferable. This range is preferable because the linear expansion coefficient tends to be low. Moreover, the alkyl group may have a substituent. Examples of the substituent that the alkyl group may have include a halogen atom, a cyano group, a nitro group, and a sulfo group. Among these, it is preferable to have a halogen atom, and a fluorine atom is particularly preferable. Within this range, the linear expansion coefficient tends to be low.
In the aromatic compound of R ^16, the number of elements forming one ring is 5 or more and 8 or less, and a single ring or two rings may be condensed. Specifically, it is a benzene ring, a condensed aromatic ring or a heterocyclic ring. Among these, a monocyclic benzene ring or a condensed aromatic ring obtained by condensing a benzene ring is preferable because the coefficient of linear expansion tends to be low.
The number of condensed aromatic rings is not particularly limited, but is preferably 2 or more and 5 or less because heat resistance and optical properties tend to be compatible.
The heterocyclic ring is not particularly limited, and specific examples include furan, thiophene, pyrrole, imidazole, pyridine, pyrimidine, pyrazine, oxazole, benzimidazole, benzoxazole and the like.
Examples of the substituent that the aromatic compound may have include an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an amino group, and a hydroxyl group.
The alkyl group having 1 to 6 carbon atoms and the alkoxy group having 1 to 6 carbon atoms may have a substituent.
Examples of the substituent that the alkyl group having 1 to 6 carbon atoms may have include a halogen atom and a hydroxyl group.
Examples of the substituent that the alkoxy group having 1 to 6 carbon atoms may have include a halogen atom and a hydroxyl group.

  In formula (35), R represents an alkyl group, a nitro group, an amino group, a hydroxyl group or a halogen atom.

The alkyl group is not particularly limited, but preferably has 1 or more carbon atoms. On the other hand, it is preferably 8 or less, and more preferably 5 or less. By being in these ranges, the compatibility with the solvent tends to be improved.
The alkyl group may have a substituent, and examples thereof include an amino group, a hydroxyl group, a nitro group, and a halogen atom.

  Examples of the diamine residue having the structure represented by the formula (35) include 2,6-diaminotoluene, 2,5-diaminotoluene, 2,4-diaminotoluene, 3,4-diaminotoluene, 2,3 -Diaminotoluene, 4-fluoro-1,2-phenylenediamine, 4-fluoro-1,3-phenylenediamine, 4-nitro-1,2-phenylenediamine, 4-nitro-1,3-phenylenediamine, 2- Nitro-1,2-phenylenediamine, 3-trifluoromethyl-1,5-phenylenediamine, 4-trifluoromethyl-1,5-phenylenediamine, 4-trifluoromethyl-1,2-phenylenediamine, 3- Hydroxy-1,5-phenylenediamine, 4-hydroxy-1,5-phenylenediamine, 4-hydroxy-1,2-fur Derived diamine residue from a diamine compound such Nirenjiamin like.

  Examples of the tetracarboxylic acid residue in which two or more aromatic rings are bonded by a quaternary carbon atom include 9,9-bis (3,4-dicarboxyphenyl) fluorene dianhydride, 4,4′-isopropyl acetate. Redene diphthalic anhydride, 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 2,2-bis (2,3 A tetracarboxylic acid residue derived from a tetracarboxylic dianhydride such as -dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride.

  Examples of tetracarboxylic acid residues in which two or more aromatic rings are bonded by a hexavalent sulfur atom include 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, 2,3,3, and the like. ', 4'-Diphenylsulfonetetracarboxylic dianhydride, 2,2', 3,3'-diphenylsulfonetetracarboxylic dianhydride, 4,4 '-[p-sulfonylbis (phenylenesulfanyl)] diphthalic acid Examples include tetracarboxylic acid residues derived from tetracarboxylic dianhydrides such as anhydrides and 3,3 ′-[p-sulfonylbis (phenylenesulfanyl)] diphthalic anhydride.

  Examples of the diamine residue in which two or more aromatic rings are bonded by a quaternary carbon atom include 2,2-bis (4-aminophenyl) hexafluoropropane and 2,2-bis (3-aminophenyl) hexa. Fluoropropane, 2,2-bis (4-aminophenyl) propane, 2,2-bis (3-aminophenyl) propane, 1,3-bis [2- (4-aminophenyl) -2-propyl] benzene, 1,4-bis [2- (4-aminopheni) -2-propyl] benzene, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, 2,2-bis (3-amino-4) -Hydroxyphenyl) propane, 9,9-bis (4-aminophenyl) fluorene, 9,9-bis (3-aminophenyl) fluorene, 9,9-bis (2-aminophenyl) Fluorene, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis [4- From diamine compounds such as {4-amino-2- (trifluoromethyl) phenoxy} phenyl] hexafluoropropane and 2,2-bis {4- (4-aminophenoxy) -3,5-dibromophenyl} hexafluoropropane Derived diamine residues are mentioned.

  Examples of the diamine residue in which two or more aromatic rings are connected by a hexavalent sulfur atom include 4,4′-diaminodiphenylsulfone, 3,3′-diaminodiphenylsulfone, and 3,4′-diaminodiphenylsulfone. 4,4′-bis (4-aminophenylenesulfanyl) diphenylsulfone, 3,3′-bis (4-aminophenylenesulfanyl) diphenylsulfone, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4 Derived from diamine compounds such as-(3-aminophenoxy) phenyl] sulfone, 2,2-bis (3-amino-4-hydroxyphenyl) sulfone, 3,3 ', 4,4'-tetraaminodiphenylsulfone A diamine residue is mentioned.

(Physical properties of polyimide precursor and / or polyimide contained in the composition)
The weight average molecular weight (Mw) of the polyimide precursor and / or polyimide contained in the composition is not particularly limited, but is usually 1000 or more, preferably 3000 or more, more preferably 5000 or more, more preferably, in terms of polystyrene equivalent weight average molecular weight. 10,000 or more. Moreover, it is 200000 or less normally, Preferably it is 180000 or less, More preferably, it is 150,000 or less. By being in this range, the solubility, solution viscosity, composition viscosity, melt viscosity, and the like are in a range that can be easily handled by ordinary production equipment, which is preferable. The polystyrene-reduced weight average molecular weight can be determined by gel permeation chromatography (GPC).

  The number average molecular weight (Mn) of the polyimide precursor and / or polyimide contained in the composition is not particularly limited, but is usually 500 or more, preferably 1000 or more, more preferably 2500 or more, more preferably, in terms of number average molecular weight in terms of polystyrene. It is 5000 or more. Moreover, it is usually 100,000 or less, preferably 90000 or less, more preferably 80000 or less. By being in this range, solubility, solution viscosity, composition viscosity, melt viscosity, and the like are in a range that can be easily handled by ordinary production equipment, which is preferable. The number average molecular weight of the polyimide precursor and / or polyimide can be measured by the same method as the weight average molecular weight.

  The molecular weight distribution (PDI, (weight average molecular weight / number average molecular weight (Mw / Mn))) of the polyimide precursor and / or polyimide contained in the composition is usually 1 or more, preferably 1.1 or more, more preferably 1 .2 or more, usually 10 or less, preferably 9 or less, more preferably 8 or less. The molecular weight distribution is preferably in this range in that a composition with high uniformity tends to be obtained. Further, in the prevention of whitening of the film, being in the above range tends to obtain a film excellent in uniformity of components in the film, suppression of whitening and smoothness of the film. In addition, the molecular weight distribution of a polyimide precursor precursor and / or a polyimide can be calculated | required from the value of the said weight average molecular weight and a number average molecular weight.

  There is no restriction | limiting in particular in the imidation ratio of the polyimide precursor contained in a polyimide precursor composition. Usually, it is less than 100%, preferably 80% or less, more preferably 60% or less, and further preferably 50% or less. There is no lower limit, and the imidation rate may be 0%. It is preferable for the imidization ratio to be in this range because solubility in a solvent used for the polyimide precursor composition is increased and the stability of the polyimide precursor composition tends to increase. The imidation ratio of the polyimide precursor contained in the polyimide precursor composition can be determined by a conventionally known method such as the NMR method, the IR method, and the titration method.

(Polyimide precursor and / or other components of polyimide composition)
The polyimide precursor and / or polyimide composition of the present invention can contain other components in addition to the polyimide precursor and / or polyimide and solvent described above as long as the effects of the present invention are not impaired. Examples of other components include surfactants, solvents, antioxidants, lubricants, colorants, stabilizers, UV absorbers, antistatic agents, flame retardants, plasticizers, mold release agents, leveling agents, and antifoaming agents. Etc. Moreover, you may mix | blend inorganic type fillers or organic type fillers, such as a powder form, a granular form, plate shape, and a fiber form, as long as the objective of invention is not impaired as needed. These additive components may be added at any stage of any process for producing a polyimide precursor and / or a polyimide composition.

  Among these components, it is preferable to include a leveling agent because the smoothness of the film tends to be improved. Examples of the leveling agent include silicone compounds. The silicone compound is not particularly limited. For example, polyether-modified siloxane, polyether-modified polydimethylsiloxane, polyether-modified hydroxyl group-containing polydimethylsiloxane, polyether-modified polymethylalkylsiloxane, polyester-modified polydimethylsiloxane, polyester-modified hydroxyl group Examples thereof include polydimethylsiloxane, polyester-modified polymethylalkylsiloxane, aralkyl-modified polymethylalkylsiloxane, highly polymerized silicone, amino-modified silicone, amino-derivative silicone, phenyl-modified silicone, and polyether-modified silicone.

(Production of polyimide precursor contained in the composition)
Reaction which obtains a polyimide precursor from tetracarboxylic dianhydride and a diamine compound can be performed on conventionally known conditions. There are no particular limitations on the order of addition or addition method of the tetracarboxylic dianhydride and the diamine compound. For example, a polyimide precursor can be obtained by sequentially adding a tetracarboxylic dianhydride and a diamine compound to a solvent and stirring at an appropriate temperature.

The amount of the diamine compound is usually 0.7 mol or more, preferably 0.8 mol or more, and usually 1.3 mol or less, preferably 1.2 mol or less, relative to 1 mol of tetracarboxylic dianhydride. By making a diamine compound into such a range, it exists in the tendency for the yield of the polyimide precursor obtained to improve.
When the amount of the diamine compound is within this range, the viscosity of the composition tends to be in a range suitable for coating, and a tough film tends to be easily obtained.

  The concentration of the tetracarboxylic dianhydride and the diamine compound in the solvent can be appropriately set according to the reaction conditions and the viscosity of the polyimide precursor. For example, the total mass% of the tetracarboxylic dianhydride and the diamine compound is not particularly limited, but is usually 1% by mass or more, preferably 5% by mass or more, and usually 70% by mass or less, preferably with respect to the total liquid amount. Is 50% by mass or less, more preferably 40% by mass or less. By setting the reaction substrate within this range, a polyimide precursor can be obtained at a low cost and with a high yield. Furthermore, the molecular weight tends to elongate, the viscosity does not become too high, and the solution tends to be easily stirred.

The reaction temperature is not particularly limited as long as the reaction proceeds, but is usually 0 ° C. or higher, preferably 20 ° C. or higher, and usually 120 ° C. or lower, preferably 100 ° C. or lower. The reaction time is usually 1 hour or more, preferably 2 hours or more, usually 100 hours or less, preferably 42 hours or less, more preferably 24 hours or less. By performing the reaction under such conditions, a polyimide precursor can be obtained at low cost and high yield.
The pressure during the reaction may be normal pressure, increased pressure, or reduced pressure.
The atmosphere may be air or an inert atmosphere.

  The solvent used in this reaction is not particularly limited. For example, hydrocarbon solvents such as hexane, cyclohexane, heptane, benzene, toluene, xylene, mesitylene, anisole; carbon tetrachloride, methylene chloride, chloroform, 1,2-dichloroethane Halogenated hydrocarbon solvents such as chlorobenzene, dichlorobenzene and fluorobenzene; ether solvents such as diethyl ether, tetrahydrofuran, 1,4-dioxane and methoxybenzene; ketone solvents such as acetone, methyl ethyl ketone, cyclohexanone and methyl isobutyl ketone; Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl Glycol solvents such as ether acetate; Amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone; Aprotic polar solvents such as dimethyl sulfoxide; Pyridine, picoline, lutidine And heterocyclic solvents such as quinoline and isoquinoline; phenol solvents such as phenol and cresol; lactone solvents such as γ-butyrolactone, γ-valerolactone and δ-valerolactone. These solvents may be used alone or in combination of two or more in any ratio and combination.

The obtained polyimide precursor may be used as it is, or may be added to a poor solvent to be precipitated in a solid state and then re-dissolved in another solvent to obtain a polyimide precursor composition.
The poor solvent at this time is not particularly limited and may be appropriately selected depending on the type of the polyimide precursor, but an ether solvent such as diethyl ether or diisopropyl ether; a ketone solvent such as acetone, methyl ethyl ketone, isobutyl ketone, methyl isobutyl ketone; Examples thereof include alcohol solvents such as methanol, ethanol, isopropyl alcohol and the like. Among them, alcohol solvents such as isopropyl alcohol are preferable in that precipitates can be obtained efficiently, the boiling point is low, and drying is easy. These solvents may be used alone or in combination of two or more in any ratio and combination.

  The solvent for dissolving the polyimide precursor is not particularly limited. For example, hydrocarbon solvents such as hexane, cyclohexane, heptane, benzene, toluene, xylene, mesitylene, and anisole; N, N-dimethylformamide, N, N-dimethylacetamide Amide solvents such as N-methyl-2-pyrrolidone; Aprotic solvents such as dimethyl sulfoxide; Glycols such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate Solvent; and the like. Among these, anisole, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, ethylene glycol dimethyl ether and ethylene glycol monomethyl ether are particularly preferable. These solvents may be used alone or in combination of two or more in any ratio and combination.

The composition of the present invention may contain other solvents without departing from the gist of the present invention. The type is not particularly limited, but alcohol is preferred because of good coatability.
There is no restriction | limiting in particular as alcohol. The vapor pressure at 20 ° C. is not particularly limited, but is preferably 50000 Pa or less, more preferably 20000 Pa or less, further preferably 10,000 Pa or less, and more preferably 5000 Pa or less. Moreover, there is no lower limit, and the lower one is preferable, but it is 1 Pa or more, for example. When the vapor pressure is within this range, a film excellent in uniformity of the composition and in-film components, whitening suppression, and smoothness tends to be obtained.

The boiling point of the alcohol added to the composition is not particularly limited, but is preferably 60 ° C. or higher, more preferably 100 ° C. or higher, and further preferably 120 ° C. or higher. Moreover, Preferably it is 300 degrees C or less, More preferably, it is 280 degrees C or less, More preferably, it is 250 degrees C or less.
When the boiling point is within this range, the concentration change of the polyimide precursor composition during film formation such as coating is reduced, so that a film excellent in uniformity of components in the film, suppression of whitening and smoothness of the film can be obtained. There is a tendency. Furthermore, the residual solvent in the film after drying or heating tends to decrease.

  The octanol / water partition coefficient (log ρ) of the alcohol added to the composition is not particularly limited, but is preferably 0 or more, more preferably 0.5 or more, and still more preferably 1 or more. There is no upper limit, and a larger one is preferred. When log ρ is within this range, the influence of moisture on the film is reduced, and whitening during film formation tends to be suppressed.

  The ratio of alcohol added to the composition with respect to the total solvent is not particularly limited, but is preferably 50% by mass or less, more preferably 30% by mass or less, and still more preferably 20% by mass or less. Moreover, 0.1 mass% or more is preferable, 0.5 mass% or more is more preferable, and 1.0 mass% or more is further more preferable. By being in this range, the solubility of the polyimide precursor and / or polyimide is increased, and whitening during film formation tends to be suppressed.

The alcohol added to the composition is preferably at least one selected from the group consisting of aromatic alcohols, aliphatic alcohols and glycol monoether alcohols. These solvents may be used alone or in combination at any ratio.
Especially, since the solubility of a polyimide precursor and / or a polyimide becomes high, an aliphatic alcohol or glycol monoether type alcohol is preferable, and an aliphatic alcohol is especially preferable.
Among aliphatic alcohols, the number of carbon atoms is preferably 4 or more, and more preferably 5 or more. Moreover, it is preferable that it is 20 or less, and it is still more preferable that it is 15 or less.
Moreover, among aliphatic alcohols, it is preferable to have a ring and a branch, and in the case of a branch, it is particularly preferable that the branch position is β and / or γ.
By having an appropriate carbon number and / or substitution position as described above, the solubility of the polyimide precursor and / or polyimide tends to increase.

Although the alcohol added to a composition is not specifically limited, The following are mentioned specifically.
(Aromatic alcohol)
Examples of the aromatic alcohol include benzyl alcohol, salicyl alcohol, diphenylmethanol, and vanillyl alcohol.

(Aliphatic alcohol)
Examples of the aliphatic alcohol include methanol having 1 carbon; ethanol having 2 carbons; 1-propanol and 2-propanol having 3 carbons; 1-butanol, 2-butanol and isobutanol having 4 carbons. 1-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, 3-methyl-1-butanol and 2-ethyl-1-propanol having 5 carbon atoms; carbon 1-hexanol, 2-hexanol, 3-hexanol, 2-methyl-1-pentanol, 3-methyl-1-pentanol, 3-methyl-2-pentanol, 2-methyl-3-pen which are the number 6 Tanol, 2-ethyl-1-butanol, 3-ethyl-2-butanol, 2,3-dimethyl-1-butanol and cyclohexa 1-heptanol, 2-heptanol, 3-heptanol, 4-heptanol, 2-methyl-1-hexanol, 2-methyl-3-hexanol, 2-methyl-4-hexanol having 3 carbon atoms, 3- Methyl-1-hexanol, 3-methyl-2-hexanol, 3-methyl-4-hexanol, 2-ethyl-1-pentanol, 2-ethyl-3-pentanol, 2,2-dimethyl-1-pentanol 2,3-dimethyl-1-pentanol and 2,4-dimethyl-1-pentanol; 1-octanol, 2-octanol, 3-octanol, 4-octanol and 2-methyl-1- having 8 carbon atoms Heptanol, 2-methyl-3-heptanol, 2-methyl-4-heptanol, 2-ethyl-1-hexanol, 2-ethyl-3- Xanol, 2-ethyl-4-hexanol, 2-propyl-1-pentanol, 2-propyl-3-pentanol, 2-propyl-4-pentanol, 2,3-dimethyl-1-hexanol and 2,4 -Dimethyl-1-hexanol; 1-nonanol having 9 carbon atoms, 2-nonanol, 3-nonanol, 4-nonanol, 5-nonanol, 2-methyl-1-octanol, 2-methyl-3-octanol, 2- Methyl-4-octanol, 2-methyl-5-octanol, 2-methyl-6-octanol, 2-ethyl-1-heptanol, 2-ethyl-3-heptanol, 2-ethyl-4-heptanol, 2-ethyl- 5-heptanol, 2,6-dimethyl-1-heptanol, 2,6-dimethyl-4-heptanol, 3,5,5-trimethyl Til-1-hexanol, 3,5,5-trimethyl-2-hexanol and 2,2,4-trimethyl-1-hexanol; 1-decanol, 2-decanol, 3-decanol and 4-decanol having 10 carbon atoms , 5-decanol, 2-methyl-1-nonanol, 2-methyl-3-nonanol, 2-methyl-4-nonanol, 2-methyl-5-nonanol, 2-ethyl-1-octanol, 2-ethyl-3 -Octanol, 2-ethyl-4-octanol and 2-ethyl-5-octanol; 1-undecanol, 2-undecanol, 3-undecanol, 4-undecanol, 2-methyl-1-decanol, 2-ethyl having 11 carbon atoms -1-nonanol and 2-propyl-1-octanol; 1-dodecanol, 2-dos having 12 carbons Canol, 3-dodecanol, 1-ethyl-1-decanol, 2-ethyl-1-decanol, 3-ethyl-1-decanol and 2-butyl-1-octanol; 1-tridecanol having 2 to 13 carbon atoms, 2-tridecanol 3-tridecanol, 1-ethyl-1-undecanol, 2-ethyl-1-undecanol, 3-ethyl-1-undecanol and 2-butyl-1-nonanol; 1-tetradecanol having 2 to 14 carbon atoms, 2-tetra Decanol, 3-tetradecanol, 2-methyl-1-tridecanol, 2-ethyl-1-dodecanol and 2-propyl-1-undecanol; 1-pentadecanol having 15 carbon atoms, 2-pentadecanol, 3-pentadecanol, 2-methyl-1-tetradecanol, 2-ethyl-1-tride 1-hexadecanol, 2-hexadecanol, 3-hexadecanol, 2-methyl-1-pentadecanol, 2-ethyl-1-tetra having 16 carbon atoms; Decanol and 2-propyl-1-tridecanol; 1-heptadecanol, 2-heptadecanol, 3-heptadecanol, 2-methyl-1-hexadecanol, 2-ethyl-1- having 17 carbon atoms Pentadecanol and 2-propyl-1-tetradecanol; 1-octadecanol, 2-octadecanol, 3-octadecanol, 2-methyl-1-heptadecanol, 2-ethyl having 18 carbon atoms -1-hexadecanol and 2-propyl-1-pentadecanol; 1-nonadecanol, 2-nonadecanol, and 3-no having 19 carbon atoms Nadecanol, 2-methyl-1-octadecanol, 2-ethyl-1-heptadecanol and 2-propyl-1-hexadecanol; 1-eicosanol, 2-eicosanol, 3-eicosanol having 2 carbon atoms, 2 -Methyl-1-nonadecanol, 2-ethyl-1-octadecanol and 2-propyl-1-heptadecanol;

(Glycol monoether alcohol)
Examples of the glycol monoether alcohol include ethylene glycol monomethyl ether and ethylene glycol monoethyl ether.

When a film is obtained by applying a polyimide precursor or a polyimide-containing composition to a substrate and heating and / or drying, the resulting film tends to be easily affected by the environment in which the film is formed. is there. In particular, when coating or the like is performed in an environment with high humidity, the solubility of the composition decreases due to moisture absorption before drying, and a polyimide precursor or polyimide may be deposited, resulting in whitening (whitening) of the film. Further, there is a problem in that original polyimide characteristics such as heat resistance and mechanical characteristics cannot be obtained even if drying or heating is performed on a film that has been whitened. In order to solve these problems, the solvent is selected from the group consisting of ether solvents, ketone solvents, amide solvents, sulfone solvents, heterocyclic solvents, phenol solvents, lactone solvents, and ester solvents. A solvent having a vapor pressure at 20 ° C. of 50000 Pa or less (hereinafter sometimes referred to as solvent A) and an alcohol (hereinafter sometimes referred to as solvent B) may be used. The reason why whitening can be suppressed by including the solvent A and the solvent B is presumed to be because the hydrophobicity of the entire composition is increased and moisture absorption is suppressed.
The solvent B is preferably at least one selected from the group consisting of aromatic alcohols, aliphatic alcohols, and glycol monoether alcohols. These solvents may be used alone or in combination at any ratio.
Especially, since the solubility of a polyimide precursor becomes high, aliphatic alcohol or glycol monoether type | system | group alcohol is preferable, and especially aliphatic alcohol is preferable.
Among aliphatic alcohols, the number of carbon atoms is preferably 4 or more, and more preferably 5 or more. Moreover, it is preferable that it is 20 or less, and it is still more preferable that it is 15 or less.
Further, among the aliphatic alcohols, it is preferable to have a ring and a branch, and in the case of a branch, the branch position is particularly preferably a β and / or γ position.
By having an appropriate carbon number and / or substitution position as described above, the solubility of the polyimide precursor tends to increase.

The vapor pressure difference between the solvent A and the solvent B is not particularly limited, but is preferably 10,000 Pa or less, more preferably 5000 Pa or less, and still more preferably 1000 Pa or less. There is no lower limit, and the vapor pressure difference may be zero. Further, either the solvent A or the solvent B may have a higher vapor pressure.
When the vapor pressure difference is in a specific range, the concentration change of the polyimide precursor composition during film formation such as coating is reduced. Therefore, it is excellent in whitening suppression, uniformity of components in the film, and film smoothness. A film tends to be obtained. Further, the residual solvent in the film after drying or heating tends to decrease.

The difference in boiling point between the solvent A and the solvent B is not particularly limited, but is preferably 100 ° C. or lower, more preferably 80 ° C. or lower, and further preferably 50 ° C. or lower. There is no lower limit, and the boiling point difference may be zero. Further, either of the boiling points of the solvent A and the solvent B may be higher.
When the difference in boiling point is within a specific range, the concentration change of the polyimide precursor composition during film formation is reduced, and thus a film excellent in whitening suppression, uniformity of components in the film and film smoothness can be obtained. There is a tendency. Further, the residual solvent in the film after drying or heating tends to decrease.

  The ratio of the ratio of the solvent A and the solvent B to the total solvent is not particularly limited, but with respect to the solvent A, the solvent B is preferably 50% by mass or less, more preferably 30% by mass or less, and further preferably 20% by mass or less. preferable. Moreover, 0.1 mass% or more is preferable, 0.5 mass% or more is more preferable, and 1.0 mass% or more is further more preferable. When the ratio of the ratio of the solvent A and the solvent B is within this range, the solubility of the polyimide precursor is maintained and the whitening suppression effect tends to be obtained.

  Since the film formed using the above solvent is particularly excellent in transparency and low colorability, it can be suitably used for applications such as coating materials, surface protective layers, adhesives, device substrates and insulating films.

(Viscosity of composition)
The viscosity of the composition of the present invention is not particularly limited, but is usually 200 cP or more, preferably 300 cP or more, more preferably 500 cP or more at a viscosity of 20% at 25 ° C., usually 200000 cP or less, preferably 100000 cP or less, Preferably it is 80,000 cP or less. When the viscosity of the composition is within this range, it is easy to handle during production, and the film thickness tends to be uniform during film formation.
The viscosity of the composition can be measured by a conventionally known method. For example, a vibration type viscometer, an E type viscometer, or the like can be used.

(Concentration of composition)
The concentration of the polyimide precursor and / or polyimide contained in the composition of the present invention is not particularly limited, but is usually 3% by mass or more, preferably 5% by mass or more, more preferably 7% by mass or more, and usually 60%. It is not more than mass%, preferably not more than 50 mass%, more preferably not more than 45 mass%. When the concentration is within this range, the production becomes easy, and the film thickness tends to be uniform during film formation.
The concentration of the composition can be measured by a conventionally known method. For example, it can be determined by the method described above.

(Production of polyimide contained in the composition)
There is no particular limitation on the method for producing the polyimide contained in the composition. For example, the method of manufacturing a polyimide precursor and obtaining a polyimide, the method of manufacturing a polyimide directly from tetracarboxylic dianhydride and a diamine compound, etc. can be used.

(Method of manufacturing from polyimide precursor)
A polyimide can be obtained by dehydrating and cyclizing the polyimide precursor obtained by the above method in the presence of a solvent. Although imidation can be performed using any conventionally known method, for example, thermal imidization for thermal cyclization, chemical imidization for chemical cyclization, and the like can be given. These imidation reactions may be performed alone or in combination.

(Heat imidization)
Examples of the solvent for imidizing the polyimide precursor include the same solvents as those used in the reaction for obtaining the polyimide precursor. The solvent at the time of manufacturing the polyimide precursor and the solvent at the time of manufacturing the polyimide may be the same or different.
In this case, water generated by imidization may be discharged out of the system in order to inhibit the ring closure reaction. The concentration of the polyimide precursor during the imidation reaction is not particularly limited, but is usually 1% by mass or more, preferably 5% by mass or more, and usually 70% by mass or less, preferably 40% by mass or less. By carrying out in this range, the production efficiency tends to be high and the solution viscosity tends to be easy to produce.

The imidation reaction temperature is not particularly limited, but is usually 50 ° C. or higher, preferably 80 ° C. or higher, more preferably 100 ° C. or higher, and usually 300 ° C. or lower, preferably 280 ° C. or lower, more preferably 250 ° C. or lower. Performing in this range is preferable because the imidization reaction proceeds efficiently and reactions other than the imidization reaction tend to be suppressed.
The pressure during the reaction may be normal pressure, pressurization, or reduced pressure. The atmosphere may be air or an inert atmosphere.

  In addition, as an imidization accelerator for promoting imidization, a compound having a function of enhancing nucleophilicity and electrophilicity can be added. Specifically, for example, trimethylamine, triethylamine, tripropylamine, tributylamine, triethanolamine, N, N-dimethylethanolamine, N, N-diethylethanolamine, triethylenediamine, N-methylpyrrolidine, N-ethylpyrrolidine , Tertiary amine compounds such as N-methylpiperidine, N-ethylpiperidine, imidazole, pyridine, quinoline and isoquinoline; carboxylic acids such as 4-hydroxyphenylacetic acid, 3-hydroxybenzoic acid, N-acetylglycine and N-benzoylglycine Compound; Polyhydric phenol compound such as methyl 3,5-dihydroxyacetophenone, methyl 3,5-dihydroxybenzoate, pyrogallol, methyl gallate, ethyl gallate, naphthalene-1,6-diol; 2-hydroxy Lysine, 3-hydroxypyridine, 4-hydroxypyridine, 4-pyridinemethanol, N, N-dimethylaminopyridine, nicotinaldehyde, isonicotialdehyde, picolinaldehyde, picolinaldehyde oxime, nicotinaldehyde oxime, isonicotialdehyde oxime, picolinic acid Ethyl, ethyl nicotinate, ethyl isonicotinate, nicotinamide, isonicotinamide, 2-hydroxynicotinic acid, 2,2′-dipyridyl, 4,4′-dipyridyl, 3-methylpyridazine, quinoline, isoquinoline, phenanthroline, 1 , 10-phenanthroline, imidazole, benzimidazole, heterocyclic compounds such as 1,2,4-triazole; and the like.

  Among these, a tertiary amine compound or a heterocyclic compound is preferable, and triethylamine, imidazole, or pyridine is more preferable because it tends to control the imidation rate. These compounds may be used individually by 1 type, or may be used 2 or more types by arbitrary ratios and combinations.

The amount of the imidization accelerator used is usually 0.01 mol% or more, preferably 0.1 mol% or more, more preferably 1 mol% or more based on the carboxyl group or ester group. Moreover, it is preferable that it is 50 mol% or less, and it is more preferable that it is 10 mol% or less. When the usage-amount of a catalyst exists in such a range, it exists in the tendency for the imidation reaction to advance efficiently and to obtain the polyimide which controlled the imidation ratio.
Moreover, the timing which adds an imidation promoter can be adjusted suitably in order to make it a desired imidation rate, may be before a heating start, and may be during a heating. Moreover, you may add in multiple times.

(Chemical imidization)
A polyimide can be obtained by chemically imidizing a polyimide precursor using a dehydration condensing agent in the presence of a solvent.
Examples of the solvent used in the chemical imidization include the same solvents as those used in the reaction for obtaining the polyimide precursor.

  Examples of the dehydrating condensing agent include N, N-2-substituted carbodiimides such as N, N-dicyclohexylcarbodiimide and N, N-diphenylcarbodiimide; acid anhydrides such as acetic anhydride and trifluoroacetic anhydride; thionyl chloride and tosyl chloride and the like. Chlorides of: acetyl chloride, acetyl bromide, propionyl iodide, acetyl fluoride, propionyl chloride, propionyl bromide, propionyl iodide, propionyl fluoride, isobutyryl chloride, isobutyryl bromide, isobutyryl iodide, isobuty Ryl fluoride, n-butyryl chloride, n-butyryl bromide, n-butyryl iodide, n-butyryl fluoride, mono-, di-, tri-chloroacetyl chloride, mono-, di-, tri Bromoacetyl chloride, mono-, di-, tri-iodoacetyl chloride, mono-, di-, tri-fluoroacetyl chloride, chloroacetic anhydride, phenylphosphonic dichloride, thionyl chloride, thionyl bromide, thionyl iodide, thionyl fluoride Halide compounds such as rides; Phosphorus compounds such as phosphorus trichloride, triphenyl phosphite, and cyanide diethyl phosphate; and the like.

  Among these, acid anhydrides and halogenated compounds are preferable, and in particular, acid anhydrides tend to allow the imidization reaction to proceed efficiently and to obtain a polyimide with a controlled imidization rate. preferable. These compounds may be used individually by 1 type, or may be used 2 or more types by arbitrary ratios and combinations.

  The amount of these dehydrating condensing agents used is usually 0.1 mol or more, preferably 0.2 mol or more, and usually 1.0 mol or less, preferably 0.9 mol or less, relative to 1 mol of the polyimide precursor. By setting the dehydration condensing agent within this range, the imidization rate can be controlled.

  Although there is no restriction | limiting in particular in the density | concentration of the polyimide precursor at the time of imidation reaction, Usually, 1 mass% or more, Preferably it is 5 mass% or more, and is 70 mass% or less normally, Preferably it is 40 mass% or less. By setting it within this range, the imidation rate can be controlled, production efficiency tends to be high, and the solution viscosity tends to be easy to manufacture.

The imidation reaction temperature is not particularly limited, but is usually 0 ° C. or higher, preferably 10 ° C. or higher, more preferably 20 ° C. or higher, and is usually 150 ° C. or lower, preferably 130 ° C. or lower, more preferably 100 ° C. or lower. It is preferable to carry out in this range since the imidization reaction proceeds efficiently and a polyimide having a controlled imidization rate tends to be obtained. Furthermore, it is preferable because side reactions other than the imidization reaction are suppressed.
The pressure during the reaction may be normal pressure, increased pressure, or reduced pressure. The atmosphere may be air or an inert atmosphere.

  Further, as a catalyst for promoting imidization, the above-mentioned tertiary amines and the like can be added in the same manner as in the heating imidization.

(Method for producing polyimide from tetracarboxylic dianhydride and diamine compound)
A polyimide can be directly obtained from a tetracarboxylic dianhydride and a diamine compound using a conventionally known method. This method performs imidization from synthesis of a poimide precursor to imidization without stopping the reaction or isolating the precursor.

  There are no particular limitations on the order and method of addition of tetracarboxylic dianhydride and diamine compound. For example, the temperature at which the reaction until imidization proceeds by sequentially adding tetracarboxylic dianhydride and diamine compound to the solvent. The polyimide is obtained by stirring at.

  The amount of the diamine compound is usually 0.7 mol or more, preferably 0.8 mol or more, and usually 1.3 mol or less, preferably 1.2 mol or less, relative to 1 mol of tetracarboxylic dianhydride. By setting the amount of the diamine compound in such a range, it is possible to obtain a polyimide with a controlled imidation rate, and the yield of the resulting polyimide composition tends to be improved.

  The concentration of tetracarboxylic dianhydride and diamine compound in the solvent can be set as appropriate for each condition and viscosity during polymerization, but the total mass of tetracarboxylic dianhydride and diamine compound is a special setting. However, it is usually 1% by mass or more, preferably 5% by mass or more, and usually 70% by mass or less, preferably 40% by mass or less, based on the total liquid amount. When the concentration in the solvent is within an appropriate range, elongation of molecular weight tends to occur, and stirring tends to be facilitated.

Examples of the solvent used in this reaction include the same solvents as those used in the reaction for obtaining the polyimide precursor.
Moreover, also when obtaining a polyimide from a tetracarboxylic dianhydride and a diamine compound, heating imidation and / or chemical imidation can be used similarly to the case where a polyimide is obtained from a polyimide precursor. The reaction conditions for heating imidization and chemical imidization in this case are the same as described above.

(Reprecipitation and re-dissolution of polyimide contained in the composition)
The obtained polyimide may be used as it is as a polyimide composition, or may be added to a poor solvent to precipitate the polyimide in a solid state, and then re-dissolved in another solvent to be used as a polyimide composition. it can.

  The poor solvent at this time is not particularly limited and may be appropriately selected depending on the type of polyimide. For example, ether solvents such as diethyl ether and diisopropyl ether; ketone solvents such as acetone, methyl ethyl ketone, isobutyl ketone and methyl isobutyl ketone; And alcohol solvents such as methanol, ethanol, isopropyl alcohol, and the like. Among them, alcohol solvents such as isopropyl alcohol are preferable because precipitates can be obtained efficiently and the boiling point is low and the drying tends to be easy. These solvents may be used alone or in combination of two or more in any ratio and combination.

  Examples of the solvent for re-dissolving polyimide include hydrocarbon solvents such as hexane, cyclohexane, heptane, benzene, toluene, xylene, mesitylene, and anisole; N, N-dimethylformamide, N, N-dimethylacetamide, N Amide solvents such as methyl-2-pyrrolidone; aprotic solvents such as dimethyl sulfoxide; glycol solvents such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate; Etc. Among these, anisole, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, ethylene glycol dimethyl ether, and ethylene glycol monomethyl ether are particularly preferable. These solvents may be used alone or in combination of two or more in any ratio and combination.

  The composition of the present invention may contain other solvents without departing from the gist of the present invention. The type is not particularly limited, but alcohol is preferred because of good coatability. Preferred alcohols are the same as those described above.

  A coupling agent such as a silane coupling agent or a titanium coupling agent can be added to the composition of the present invention in order to adjust the adhesiveness to the coated body.

  Examples of the silane coupling agent include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropyltripropoxysilane, γ-aminopropyltributoxysilane, γ-aminoethyltriethoxysilane, γ -Aminoethyltrimethoxysilane, γ-aminoethyltripropoxysilane, γ-aminoethyltributoxysilane, γ-aminobutyltriethoxysilane, γ-aminobutyltrimethoxysilane, γ-aminobutyltripropoxysilane, γ-amino Examples include butyltributoxysilane.

  Examples of the titanium coupling agent include γ-aminopropyltriethoxytitanium, γ-aminopropyltrimethoxytitanium, γ-aminopropyltripropoxytitanium, γ-aminopropyltributoxytitanium, γ-aminoethyltriethoxytitanium, γ -Aminoethyltrimethoxytitanium, γ-aminoethyltripropoxytitanium, γ-aminoethyltributoxytitanium, γ-aminobutyltriethoxytitanium, γ-aminobutyltrimethoxytitanium, γ-aminobutyltripropoxytitanium, γ-amino Examples thereof include butyl tributoxy titanium.

  These coupling agents may be used individually by 1 type, or may be used 2 or more types by arbitrary ratios and combinations. The amount used at this time is preferably 0.1% by mass or more and 3% by mass or less with respect to the polyimide.

  In addition, it is also possible to mix | blend various additives as needed. For example, other powdery, granular, plate-like, fiber-like inorganic fillers and organic fillers can be blended within a range not impairing the effects of the present invention.

  These fillers may be processed into a flat shape such as a non-woven fabric or may be used in combination. Furthermore, if desired, various additives commonly used in resin compositions such as lubricants, colorants, stabilizers, antioxidants, ultraviolet absorbers, antistatic agents, flame retardants, plasticizers, mold release agents, etc. Can be blended. These various fillers and additive components may be added at any stage of any process for producing polyimide.

(Polyimide)
The polyimide according to the present invention contains a tetracarboxylic acid residue and a diamine residue, and has a partial structure selected from group III and one or more partial groups selected from group IV as a tetracarboxylic acid residue. The diamine residue has a partial structure represented by the formula (11).

Group III: The following formula (7) and formula (8) are shown.

[In Formula (7),
X ¹ represents a direct bond, an alkylene group, a carbonyl group, an ether bond or a sulfonyl group. ]

Group IV: The following formulas (9) and (10) are shown.

[In Formula (9),
n ′ and m ′ each independently represent 0 or 1,
R ⁵ and R ⁶ each independently represents an alkyl group, an alkenyl group or an aromatic ring. R ⁵ and R ⁶ may be different or the same, and may form a ring. ]

[In Formula (10),
Y ′ represents a direct bond or a divalent organic group. ]

[In Formula (11),
R ⁷ and R ⁸ each independently represents an alkyl group, an alkoxy group, an amino group or a hydroxyl group. ]

X ^{1 in} formula (7) has the same meaning as X in formula (1), and the preferred range and the substituent that may be present are also synonymous.
N ′ and m ′ in the formula (9) have the same meanings as n and m in the formula (3), respectively, and a preferable range is also the same. Moreover, R < ⁵ > and R < ⁶ > are synonymous with R < ¹ > and R < ² > of Formula (3), respectively, A preferable range and the substituent which may have are also synonymous.
Y ′ in formula (10) has the same meaning as Y in formula (4), and the preferred range and the substituent that may be present are also synonymous.
R ⁷ and R ^{8 in} the formula (11) have the same meanings as R ³ and R ^{4 in} the formula (5), respectively, and the preferred range and the substituents that may be included are also the same.

The polyimide of the present invention has a tetracarboxylic acid residue having a structure other than the partial structure represented by the above formula (7), formula (8), formula (9) and formula (10) without departing from the gist of the present invention. You may have. Moreover, you may have the diamine residue which has other than the partial structure shown by Formula (11).
Examples of the tetracarboxylic acid residue having other than the partial structure represented by the above formula (7), formula (8), formula (9) and formula (10) include the above formula (1), formula (2) and formula (3). ) And tetracarboxylic dianhydrides such as aromatic tetracarboxylic dianhydrides and aliphatic tetracarboxylic dianhydrides, shown as tetracarboxylic acid residues having other than the partial structure represented by formula (4) And tetracarboxylic acid residues derived from.
As the diamine residue having other than the partial structure represented by the above formula (11), a diamine residue derived from a diamine compound represented as a diamine residue having other than the partial structure represented by the above formula (5) Can be mentioned.

The polyimide of the present invention preferably has a tetracarboxylic acid residue and / or a diamine residue having a bent portion, since it tends to improve optical properties.
As the tetracarboxylic acid and / or diamine residue having a bent portion, the tetracarboxylic acid and / or diamine residue having a bent portion which may be included in the polyimide precursor and / or polyimide in the composition of the present invention. It is synonymous with group, and its preferable range is also synonymous.

  Among diamine residues having other than the partial structure represented by formula (11), it is preferable to have a diamine residue having a partial structure represented by formula (12) in order to improve optical properties.

[In Formula (12),
Z ′ represents a direct bond, a sulfonyl group, an alkylene group, a carbonyl group or an ether bond,
A ′ and B ′ each independently represent a direct bond, a divalent aromatic ring, a divalent heterocyclic ring or a phenyl ether group. ]

  Z ′, A ′ and B ′ in the formula (12) have the same meanings as Z, A and B in the formula (6), respectively, and preferred ranges and substituents which may be present are also synonymous.

The partial structure contained in the polyimide can be obtained by analyzing the composition of the raw material monomer by solid-state NMR, IR, or the like.
Moreover, after melt | dissolving with an alkali, it can obtain | require by gas chromatography (GC), < ¹ > H-NMR, < ¹³ > C-NMR, two-dimensional NMR, mass spectrometry, etc.

  Although the shape of the polyimide of this invention is not specifically limited, For example, various forms, such as a powder form, a pellet form, and a film form, can be taken.

  The polyimide of the present invention is preferably soluble in a solvent. Soluble in a solvent is as defined above, and the solvent used is also synonymous. By being soluble in the solvent, processing such as casting and coating becomes possible, and at that time, since imidization reaction is not involved, processing can be performed under mild conditions. Moreover, the storage stability of the solution can be improved.

(Polyimide properties)
The properties and properties of the polyimide of the present invention are not particularly limited without departing from the gist of the present invention.

The tensile strength of the polyimide of the present invention is not particularly limited, but is usually 50 MPa or more, preferably 70 MPa or more, usually 400 MPa or less, preferably 300 MPa or less.
The tensile elastic modulus is not particularly limited, but is usually 1000 MPa or more, preferably 1500 MPa or more, and usually 20 GPa or less, preferably 10 GPa or less.
The tensile elongation is not particularly limited, but is usually 5% GL or more, preferably 10% GL or more, more preferably 20 GL% or more, and usually 300% GL or less, preferably 200 GL% or less.
By being in the range as described above, there is strength, which is particularly useful when a film is used. These tensile strength, tensile elastic modulus, and tensile elongation can be determined, for example, by measuring film-like polyimide with a tensile tester.

  The glass transition temperature of the polyimide of the present invention is not particularly limited, but is usually 100 ° C. or higher, preferably 150 ° C. or higher, more preferably 200 ° C. or higher. When the glass transition temperature is within this range, heat resistance can be obtained. The glass transition temperature can be measured by using, for example, differential scanning calorimetry, viscoelasticity measurement, thermogravimetric / differential thermal simultaneous analysis, and the like.

  The linear expansion coefficient of the polyimide of the present invention is usually 60 ppm / K or less, preferably 50 ppm / K or less, more preferably 45 ppm / K or less, still more preferably 40 ppm / K, particularly preferably in the range of 100 ° C. to 150 ° C. 30 ppm / K or less. This range is preferable because, for example, when a device using polyimide as a film is produced, the dimensional stability is high, and it is difficult for members such as electronic elements and color filters to break and deform. Although the measuring method is not specifically limited, For example, it can measure by the method of an Example using a film-like polyimide.

  The transmittance | permeability of the polyimide of this invention is set as a film, When the film thickness is 1-100 micrometers, the transmittance | permeability with respect to a 500 nm light ray is 55% or more normally, Preferably it is 60% or more, More preferably, it is 70% or more. By being in this range, the light emission efficiency of the device can be used effectively. The transmittance can be measured by the method described in JIS K 7361-1 (1997).

  When the polyimide of the present invention is used as a film, the retardation is a wavelength to be used, for example, an arbitrary wavelength between 400 and 800 nm for device use, and the retardation in the thickness direction of the film (Rth) is usually 300 nm or less. Preferably it is 200 nm or less, More preferably, it is 170 nm or less, More preferably, it is 150 nm or less, More preferably, it is 140 nm or less, Most preferably, it is 120 nm or less. The in-plane retardation (R0) of the film is usually 10 nm or less, preferably 5 nm or less, more preferably 3 nm or less, and even more preferably 1 nm or less. This range is preferable because the visibility of the device is improved.

  The polyimide of the present invention is useful for film applications. In addition to film applications, it can be applied to a wide range of applications. For example, it can be used for production of a flexible solar cell member, a display member, a liquid crystal display carrier, a heat-resistant insulating tape, a heat-resistant adhesive tape, a capacitor or a film for a flexible printed circuit board. Further, for example, it can be used for manufacturing a structural member reinforced with glass fiber or carbon fiber, a small coil bobbin, or a molded product of a terminal insulating tube.

  Further, it can be used for the production of laminated materials such as insulating spacers, magnetic head spacers or transformer spacers. Moreover, it can be used for manufacture of enamel coating materials such as electric wire / cable insulation coating materials, low-temperature storage tanks, space insulation materials, and integrated circuits. Furthermore, it can also be used for the production of heat-resistant yarns, woven fabrics or nonwoven fabrics.

(Polyimide film)
In addition to the polyimide film using the polyimide according to the present invention, a polyimide film having the following characteristics is also preferably used.
That is, the present invention is a polyimide film containing a tetracarboxylic acid residue and a diamine residue, wherein at least one of the tetracarboxylic acid residue and the diamine residue has a bent portion, and the linear expansion coefficient is 60 ppm / It is related also to the polyimide film characterized by being below K and retardation being below 200 nm.
The definition of the bending part which at least any one of a tetracarboxylic acid residue and a diamine residue has is the same as that of the bending part mentioned above, and its preferable structure is also the same.

  The linear expansion coefficient of the polyimide film may be 60 ppm / K or less, preferably 50 ppm / K or less, more preferably 45 ppm / K or less, still more preferably 40 ppm / K, and particularly preferably 30 ppm / K or less. Moreover, there is no lower limit and the lower one is preferable. This range is preferable because, for example, when a device using polyimide as a film is produced, the dimensional stability is high, and it is difficult for members such as electronic elements and color filters to break and deform. Although the measuring method is not specifically limited, For example, it can measure by the method of an Example using a film-like polyimide.

The method of setting the linear expansion coefficient of the polyimide film to 60 ppm / K or less is not particularly limited. For example, a method using a composition containing at least one of the polyimide precursor and polyimide, a method of adding a filler, and the like, film The linear expansion coefficient of a polyimide film can be made in the said range by performing the method of extending | stretching etc. and adjusting these suitably.
The filler and the like are not particularly limited, and examples thereof include inorganic fillers such as powder, granule, plate, and fiber, or organic fillers.

Examples of inorganic fillers include oxides such as silica, diatomaceous earth, barium ferrite, beryllium oxide, pumice and pumice balloon; hydroxides such as aluminum hydroxide, magnesium hydroxide and basic magnesium carbonate; calcium carbonate Carbonates such as magnesium carbonate, dolomite and dosonite; sulfates and sulfites such as calcium sulfate, barium sulfate, ammonium sulfate and calcium sulfite; talc, clay, mica, asbestos, glass fiber, glass balloon, glass beads, calcium silicate Silicates such as carbon fiber, carbon black, graphite and carbon hollow spheres; powders of molybdenum sulfide, zinc borate, barium metaborate, calcium borate, sodium borate, boron fiber, etc. Shape, granular, board , Fibrous inorganic fillers; powdered, granular, fibrous, whisker-like metal fillers of metal elements, metal compounds, alloys, etc .; silicon carbide, silicon nitride, zirconia, aluminum nitride, titanium carbide, potassium titanate, etc. Powdered, granular, fibrous, and whisker-like ceramic fillers.

On the other hand, examples of the organic filler include carbon nanotubes, fullerenes, aromatic polyamide fibers, cellulose fibers, nylon fibers, polyester fibers, polypropylene fibers, thermosetting resin powders, and rubbers.
As a filler, what processed into flat form, such as a nonwoven fabric, may be used, and several materials may be mixed and used.
The linear expansion coefficient can be measured by a thermomechanical device.

The retardation of the polyimide film may be 200 nm or less, preferably 170 nm or less, more preferably 150 nm or less, still more preferably 140 nm or less, and particularly preferably 120 nm or less. The in-plane retardation (R0) of the film is usually 10 nm or less, preferably 5 nm or less, more preferably 3 nm or less, and even more preferably 1 nm or less. This range is preferable because the visibility of the device is improved.
The method of setting the retardation of the polyimide film to 200 nm or less is not particularly limited. For example, a method using a composition containing at least one of the polyimide precursor and polyimide, a method of mixing a compound having a negative retardation, or a resin, The retardation of a polyimide film can be made into the said range by using the method etc. which form into a film using the base material which has a linear expansion coefficient equivalent to a polyimide.
The compound or resin having negative retardation is not particularly limited, and examples thereof include a styrene compound, an acrylic compound, a styrene resin, and an acrylic resin.
Examples of the base material having a linear expansion coefficient equivalent to that of polyimide include a metal foil and a resin substrate.
Retardation can be measured by a retardation film / optical material inspection apparatus or the like.

  When the film thickness is 1 to 100 μm, the transmittance of the polyimide film of the present invention is usually 55% or more, preferably 60% or more, and more preferably 70% or more with respect to a light beam of 500 nm. By being in this range, the light emission efficiency of the device can be used effectively. The transmittance can be measured by the method described in JIS K 7361-1 (1997).

  In the polyimide film of the present invention, the yellowness (yellow index: YI) at a film thickness of 10 μm is usually −10 or higher, preferably −5 or higher, more preferably −1 or higher. On the other hand, it is usually 20 or less, preferably 15 or less, more preferably 10 or less. By being in this range, when polyimide is used as a device member, the efficiency of light emission can be used effectively. The yellow index can be measured by using, for example, a spectral color meter.

  The thickness of the polyimide film is not particularly limited, but is usually 1 μm or more, preferably 2 μm or more, and is usually 200 μm or less, preferably 100 μm or less. When the film has an appropriate thickness, sufficient resistance can be maintained and the flexible device can be thinned.

(Production method of polyimide film)
Although there is no restriction | limiting in particular in the manufacturing method of the polyimide film of this invention, For example, after apply | coating the composition containing the polyimide precursor and / or polyimide obtained by the said method on a carrier substrate, it obtains by volatilizing a solvent. be able to. The application method is not particularly limited as long as it can form a layer having a uniform thickness. For example, die coating, spin coating, screen printing, spraying, a casting method using an applicator, a method using a coater, and spraying. Examples thereof include a method, a dipping method, a calendar method, and a casting method. These methods can be appropriately selected according to the application area, the shape of the surface to be applied, and the like.

  As the substrate of the material to be coated, for example, a substrate made of glass such as float glass or soda glass, or a plastic such as polyethylene terephthalate, polycarbonate, or polyolefin can be used. When applying to such a substrate, a functional silane-containing compound or a functional titanium-containing compound can be prefaced on the surface of the substrate. Further, ultraviolet treatment, plasma treatment, or the like can be performed.

  The method for volatilizing the solvent of the polyimide precursor and / or polyimide composition is not particularly limited. Usually, the solvent is volatilized by heating the applied material to be coated and / or by volatilizing the solvent under reduced pressure. The heating method is not particularly limited, and examples thereof include hot air heating, vacuum heating, infrared heating, microwave heating, heating by contact using a hot plate or a hot roll, and the like.

The heating temperature for volatilizing the solvent can be a suitable temperature depending on the type of the solvent, but is usually 20 ° C. or higher, preferably 40 ° C. or higher, more preferably 50 ° C. or higher, more preferably 60 ° C. or higher. It is. Moreover, it is 400 degrees C or less normally, Preferably it is 380 degrees C or less, More preferably, it is 350 degrees C or less, More preferably, it is 300 degrees C or less. When the temperature is equal to or higher than the above lower limit, the residual solvent can be reduced and the film can be sufficiently dried. Moreover, by being below the said upper limit, the bubble etc. which generate | occur | produce by rapid volatilization can be suppressed and an external appearance and quality can be kept favorable.
The heating atmosphere may be either air or an inert atmosphere, and is not particularly limited. However, if the polyimide film is required to be colorless and transparent, it can be heated under an inert atmosphere such as nitrogen to suppress coloring. preferable.

  The method for peeling the polyimide film formed on the carrier by coating and drying is not particularly limited, and examples thereof include laser peeling, mechanical peeling, and peeling by immersion in water or hot water.

  As a method for producing a film and / or a polyimide film using a polyimide precursor composition, a method for melting and molding the polyimide precursor resin and / or polyimide resin, for example, an injection molding method, an extrusion molding method, a hollow molding method. Method, compression molding method, laminate formation method, roll processing method, stretching method, stamp processing method, hot press method, T-die method and the like.

  Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. In addition, the following examples are shown in order to describe the present invention in detail, and the present invention is not limited to the following examples unless it is contrary to the gist thereof. In addition, the values of various conditions and evaluation results in the following examples have meanings as preferable values of the upper limit or the lower limit in the embodiment of the present invention, and the preferable range is the above upper limit or lower limit value. It may be a range defined by a combination of values of the examples or values between the examples.

[Example 1]
In a four-necked flask equipped with a reflux nitrogen gas inlet tube, a condenser, and a stirrer, 5.7 g (0.019 mol) of 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride (BPDA), 3, 2.6 g (0.009 mol) of 3 ′, 4,4′-bicyclohexanetetracarboxylic dianhydride (H-BPDA), 1.4 g (0.006 mol) of pyromellitic anhydride (PMDA), 2,2 '-Bis (trifluoromethyl) benzidine (6F-m-TB) 5.6 g (0.018 mol), 4,4'-diaminodiphenylsulfone 4.3 g (0.018 mol), N-methyl-2-pyrrolidone ( NMP) 73 g was added. The mixture was heated while stirring and reacted at 80 ° C. for 6 hours to obtain a composition 1 containing a polyimide precursor.

(Preparation of polyimide film)
The obtained composition 1 was applied on a glass substrate using a 100 μm applicator and heated at 350 ° C. for 30 minutes to obtain a polyimide film 1 having a thickness of 10 μm.

(Measurement of linear expansion coefficient (CTE))
A polyimide film 1 which has been conditioned overnight in a constant temperature and humidity room with a temperature of 25 ° C. and a humidity of 50% is punched out with a super straight cutter with a width of 4 mm and a length of 40 mm, and measured using TMA / SS6100 manufactured by SII Nanotechnology. did. Table 2 shows the CTE between 100 ° C. and 150 ° C. when the distance between chucks of the film sample is 10 mm, nitrogen is 120 mL / min, and the temperature rising rate is 10 ° C./min from 30 ° C. to 210 ° C.

(Measurement of retardation (Rth) value in the thickness direction of the film)
The retardation (Rth) value in the thickness direction of the polyimide film 1 was measured and calculated using a measurement retardation film / optical material inspection apparatus ("RETS100" manufactured by Otsuka Electronics Co., Ltd.). The measurement results are shown in Table 2. The retardation (Rth) value in the thickness direction of the film used this time is a value at a wavelength of 460 nm and a film thickness of 10 μm.

(Measurement of yellow index (YI) value)
The yellow index (YI) value of the polyimide film 1 was measured using SM color computer SM5 manufactured by Suga Test Instruments Co., Ltd. The YI value used this time is a value calculated as a YI value per 10 μm of film thickness.

[Example 2]
BPAD of Example 1 was 1.7 g (0.006 mol), H-BPDA was 1.8 g (0.006 mol), PMDA was 3.9 g (0.018 mol), and 6 F-m-TB was 5.5 g (0 0.017 mol), polyimide precursor composition 2 and polyimide film 2 were prepared in the same manner as in Example 1 except that 3.2 g (0.013 mol) of 4,4′-diaminodiphenylsulfone and NMP were changed to 65 g. Obtained. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 3]
5.3 g (0.018 mol) of BPDA of Example 1, 2.5 g (0.008 mol) of H-BPDA, 1.3 g (0.006 mol) of PMDA, 7.9 g of 6F-m-TB (0 0.025 mol), 4,4′-diaminodiphenyl sulfone was changed to 2.0 g (0.008 mol), and NMP was changed to 71 g. Obtained. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 4]
5.4 g (0.018 mol) of BPDA of Example 1, 2.5 g (0.008 mol) of H-BPDA, 1.3 g (0.006 mol) of PMDA, and 9.5 g of 0F-m-TB (0 0.03 mol), 4,4′-diaminodiphenyl sulfone was changed to 0.8 g (0.003 mol) and NMP was changed to 78 g, and polyimide precursor composition 4 and polyimide film 4 were obtained in the same manner as in Example 1. It was. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 5]
In a four-necked flask equipped with a reflux nitrogen gas inlet tube, a condenser, a Dean-Stark agglomerator filled with toluene, and a stirrer, 4.9 g (0.017 mol) of BPDA, 2.3 g (0.007 mol) of H-BPDA, PMDA1 0.2 g (0.006 mol), 6F-m-TB 8.6 g (0.027 mol), 4,4′-diaminodiphenylsulfone 0.7 g (0.003 mol), NMP 71 g, and toluene 14 g were added. The mixture was heated to reflux at 200 ° C. for 13 hours with stirring to obtain a polyimide composition 5.

[Example 6]
4.1 g (0.014 mol) of BPDA of Example 1, 2.1 g (0.007 mol) of H-BPDA, 1.9 g (0.009 mol) of PMDA, and 8.4 g of 0F-m-TB (0 .026 mol), 2.2 g (0.009 mol) of 4,4′-diaminodiphenylsulfone, and 82 g of NMP were changed to 1.9 g of 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride. A polyimide precursor composition 6 and a polyimide film 6 were obtained in the same manner as in Example 1 except that (0.005 mol) was added. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 7]
5.4 g (0.018 mol) of BPDA of Example 6, 1.2 g (0.004 mol) of H-BPDA, 1.3 g (0.006 mol) of PMDA, 3,3 ′, 4,4′-diphenyl 1.5 g (0.004 mol) of sulfonetetracarboxylic dianhydride, 7.9 g (0.025 mol) of 6F-m-TB, 2.0 g (0.008 mol) of 4,4′-diaminodiphenylsulfone, A polyimide precursor composition 7 and a polyimide film 7 were obtained in the same manner as in Example 6 except that NMP was changed to 78 g. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 8]
5.4 g (0.018 mol) of BPDA of Example 6, 2.0 g (0.007 mol) of H-BPDA, 1.3 g (0.006 mol) of PMDA, 3,3 ′, 4,4′-diphenyl 0.6 g (0.002 mol) of sulfonetetracarboxylic dianhydride, 7.9 g (0.025 mol) of 6F-m-TB, 2.0 g (0.008 mol) of 4,4′-diaminodiphenylsulfone, A polyimide precursor composition 8 and a polyimide film 8 were obtained in the same manner as in Example 6 except that NMP was changed to 77 g. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 9]
5.9 g (0.019 mol) of BPDA of Example 6, 1.9 g (0.006 mol) of H-BPDA, 1.4 g (0.006 mol) of PMDA, 7.7 g of 0F-m-TB (0 0.024 mol), 4,4′-diaminodiphenylsulfone 1.2 g (0.005 mol), NMP 76 g, and 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride 9, A polyimide precursor composition 9 and a polyimide film 9 were obtained in the same manner as in Example 6 except that the amount was changed to 1.1 g (0.003 mol) of 9-bis (4-aminophenyl) fluorene. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 10]
9.8 g (0.033 mol) of BPDA of Example 6, 2.3 g (0.007 mol) of H-BPDA, 2.4 g (0.011 mol) of PMDA, and 18.0 g (0 of 0) of F-m-TB 0.056 mol), 4.7 g (0.019 mol) of 4,4′-diaminodiphenylsulfone, and 141 g of NMP, and 2,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride was changed to 2, The same as Example 6 except that the amount was changed to 9.9 g (0.022 mol) of 2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride. The polyimide precursor composition 10 and the polyimide film 10 were obtained by the method. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 11]
3.8 g (0.013 mol) of BPDA of Example 10, 2.0 g (0.007 mol) of H-BPDA, 1.7 g (0.008 mol) of PMDA, 2,2-bis (3,4-di Carboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride 2.1 g (0.005 mol), 6F-m-TB 7.9 g (0.025 mol), 4,4 A polyimide precursor composition 11 and a polyimide film 11 were obtained in the same manner as in Example 10, except that 2.0 g (0.008 mol) of '-diaminodiphenylsulfone and 79 g of NMP were changed. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 12]
Example 10 except that BPDA of Example 10 was changed to 6.6 g (0.022 mol), H-BPDA was changed to 2.2 g (0.007 mol), PMDA was changed to 4.9 g (0.022 mol), and NMP was changed to 139 g. The polyimide precursor composition 12 and the polyimide film 12 were obtained by the same method. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 13]
5.2 g (0.018 mol) of BPDA of Example 9, 1.8 g (0.006 mol) of H-BPDA, 1.3 g (0.006 mol) of PMDA, 6.2 g of 6F-m-TB (0 .020 mol), 1.9 g (0.008 mol) of 4,4′-diaminodiphenylsulfone, and 53 g of NMP, and 9,9-bis (4-aminophenyl) fluorene with 2,2-bis (3- A polyimide precursor composition 13 and a polyimide film 13 were obtained in the same manner as in Example 9 except that the amount was changed to 1.1 g (0.003 mol) of amino-4-hydroxyphenyl) -hexafluoropropane. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 14]
6.6 g (0.022 mol) of BPAD of Example 1, 3.0 g (0.010 mol) of H-BPDA, 1.6 g (0.007 mol) of PMDA, 9.6 g of 6F-m-TB (0 0.030 mol), NMP was changed to 73 g, and 4,4′-diaminodiphenyl sulfone was changed to 3.4 g (0.010 mol) of 1,4-bis [2- (4-aminophenyl) -2-propyl] benzene. A polyimide precursor composition 14 and a polyimide film 14 were obtained by the same method as in Example 1 except that. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Example 15]
Except that 1,4-bis [2- (4-aminophenyl) -2-propyl] benzene of Example 14 was changed to 1,3-bis [2- (4-aminophenyl) -2-propyl] benzene A polyimide precursor composition 14 and a polyimide film 14 were obtained by the same method as in Example 13. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 1]
In a four-necked flask equipped with a reflux nitrogen gas introduction tube, a condenser and a stirrer, BPDA 4.4 g (0.015 mol), H-BPDA 2.3 g (0.008 mol), PMDA 3.3 g (0.015 mol), 6F- 12.2 g (0.038 mol) of m-TB and 76 g of NMP were added. The mixture was heated with stirring and reacted at 80 ° C. for 6 hours to obtain a composition 16 containing a polyimide precursor. A polyimide film 16 was obtained from the obtained composition 16 in the same manner as in Example 1. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 2]
In a four-necked flask equipped with a reflux nitrogen gas introduction tube, a condenser, and a stirrer, H-BPDA 1.8 g (0.006 mol), PMDA 5.2 g (0.024 mol), 6F-m-TB 7.2 g (0.023 mol) ), 4,4′-diaminodiphenylsulfone 1.9 g (0.008 mol) and NMP 64 g were added. The mixture was heated while stirring and reacted at 80 ° C. for 6 hours to obtain a composition 17 containing a polyimide precursor. A polyimide film 17 was obtained from the obtained composition 17 in the same manner as in Example 1. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 3]
In a four-necked flask equipped with a reflux nitrogen gas introduction tube, a condenser, a Dean-Stark agglomerator filled with anisole, and a stirrer, 14.6 g (0.050 mol) of BPDA, 15.2 g (0.050 mol) of H-BPDA, m-TB 16.0 g (0.05 mol), 4,4′-diaminodiphenyl sulfone 9.9 g (0.04 mol), 3,3′-diaminodiphenyl sulfone 2.5 g (0.01 mol), NMP 87 g, anisole 87 g added. The mixture was heated to reflux at 200 ° C. for 13 hours with stirring to obtain a polyimide composition 18. A polyimide film 18 was obtained from the obtained composition 18 in the same manner as in Example 1. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 4]
5.6 g (0.019 mol) of BPAD of Example 1, 1.4 g (0.006 mol) of PMDA, 7.7 g (0.024 mol) of 6F-m-TB, and 4,4′-diaminodiphenylsulfone Other than changing 2.0 g (0.008 mol), NMP to 76 g, and changing H-BPDA to 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride 2.3 g (0.006 mol) Obtained a polyimide precursor composition 19 and a polyimide film 19 in the same manner as in Example 1. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 5]
In a four-necked flask equipped with a reflux nitrogen gas inlet tube, a condenser, and a stirrer, 3.6 g (0.012 mol) of BPDA, 3.8 g (0.012 mol) of H-BPDA, 2,2′-dimethylbenzidine (m-TB ) 5.3 g (0.025 mol) and 38 g of N, N-dimethylacetamide (DMAc) were added. The mixture was heated with stirring and reacted at 80 ° C. for 6 hours to obtain a composition 21 containing a polyimide precursor. A polyimide film 21 was obtained from the resulting composition 21 in the same manner as in Example 1. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 6]
In a four-necked flask equipped with a reflux nitrogen gas inlet tube, a condenser, and a stirrer, 5.8 g (0.02 mol) of BPDA, 6.4 g (0.020 mol) of 6F-m-TB, N, N-dimethylacetamide (DMAc) 37g was added. The mixture was heated with stirring and reacted at 80 ° C. for 6 hours to obtain a composition 22 containing a polyimide precursor. A polyimide film 22 was obtained from the obtained composition 22 in the same manner as in Example 1. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 7]
H-BPDA 21.2 g (0.069 mol), m-TB 14.7 g (0.070 mol), and DMAc 108 g were added to a four-necked flask equipped with a refluxing nitrogen gas introduction tube, a condenser, and a stirrer. The mixture was heated with stirring and reacted at 80 ° C. for 6 hours to obtain a composition 23 containing a polyimide precursor. A polyimide film 23 was obtained from the obtained composition 23 in the same manner as in Example 1. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 8]
Comparative Example 7 and Comparative Example 7 except that 6.8 g (0.022 mol) of H-BPDA, 5.9 g (0.023 mol) of 4,4′-diaminodiphenylsulfone, and DMAc were changed to 37 g of NMP. The polyimide precursor composition 24 and the polyimide film 24 were obtained by the same method. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Comparative Example 9]
PMDA of Comparative Example 2 was changed to 3.2 g (0.015 mol), 6F-m-TB was changed to 8.8 g (0.027 mol), NMP was changed to 69 g, H-BPDA was changed to BPDA 4.4 g (0.015 mol), The polyimide precursor composition 25 and the polyimide were prepared in the same manner as in Comparative Example 2 except that 4,4′-diaminodiphenylsulfone was changed to 0.9 g (0.003 mol) of 9,9-bis (4-aminophenyl) fluorene. Film 25 was obtained. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Reference Example 1]
BPDA of Comparative Example 6 was converted to 8.7 g (0.020 mol) of 2,2-bis (3,4-dicarboxyphenyl) -1,1,1,3,3,3-hexafluoropropane dianhydride, 6F- A polyimide precursor composition 26 and a polyimide film 26 were obtained in the same manner as in Comparative Example 6 except that m-TB was changed to 6.4 g (0.02 mol) and DMAc was changed to 46 g. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2.

[Reference Example 2]
In a four-necked flask equipped with a reflux nitrogen gas inlet tube, a condenser, and a stirrer, 2.9 g (0.01 mol) of BPDA, 3.0 g (0.01 mol) of H-BPDA, 6.4 g of 6F-m-TB (0.020 mol) ), 37 g of N, N-dimethylacetamide (DMAc) was added. The mixture was heated with stirring and reacted at 80 ° C. for 6 hours to obtain a composition 20 containing a polyimide precursor. A polyimide film 20 was obtained from the resulting composition 20 in the same manner as in Example 1. In the same manner as in Example 1, CTE, Rth, and YI of the polyimide film were measured. The results are shown in Table 2. Moreover, the ratio of the tetracarboxylic dianhydride with respect to a diamine compound was adjusted so that the viscosity of a composition might be 200-600 cP in the said raw material, and the composition 27 was obtained. The ratio is shown in Table 3.
In the same manner as in Example 1, the composition 27 was applied on a glass substrate and heated. When the obtained film was peeled off, cracks occurred and the film could not be obtained.
On the other hand, the ratio of the tetracarboxylic dianhydride with respect to the raw material diamine compound used in Example 7 was adjusted so that the viscosity of the composition was 200 to 600 cP, whereby a composition 28 was obtained. The ratio is shown in Table 3.
In the same manner as in Example 1, the composition 28 was applied on a glass substrate and heated. The obtained film did not crack and could be peeled off.

  As shown in Table 2, it was shown that the polyimide films 1 to 15 of the present invention have both a low linear expansion coefficient and a low retardation. On the other hand, it was shown that the polyimide film shown in the comparative example cannot achieve both a low linear expansion coefficient and a low retardation.

  As shown in Reference Example 2 and Table 3, the composition 28 containing the bent portion could be formed into a film even when the viscosity was reduced to 200 to 600 cP, but the composition did not contain the bent portion. 27, it was difficult to form a film when the viscosity was lowered. Therefore, it was shown that the composition can be obtained in a wide viscosity range by having a bent portion and can be applied to various coating methods. It was.

  Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. This application is a Japanese patent application filed on February 21, 2014 (Japanese Patent Application No. 2014-032147), a Japanese patent application filed on June 26, 2014 (Japanese Patent Application No. 2014-131668), and an application filed on January 6, 2015. This is based on a Japanese patent application (Japanese Patent Application No. 2015-000993), the contents of which are incorporated herein by reference.

  The polyimide precursor composition of the present invention can be used for coating materials, surface protective layers, adhesives, device substrates, insulating films and the like.

Claims (4)

A composition comprising at least one of a polyimide precursor and a polyimide,
The polyimide precursor and polyimide include a tetracarboxylic acid residue and a diamine residue,
The tetracarboxylic acid residue includes a tetracarboxylic acid residue derived from a tetracarboxylic dianhydride represented by the following formula (A), and Ar ¹ in the formula (A) is represented by the following formula (1 ′) The partial structure represented, the partial structure represented by the following formula (2) and the partial structure represented by the following formula (4 ′) ,
The diamine residue contains a diamine residue derived from a diamine compound represented by the following formula (B1) or a diisocyanate compound represented by the following formula (B2), and in the formula (B1) and the formula (B2) Ar ² represents a partial structure represented by the following formula (5),
Before SL at least one tetracarboxylic acid residue and a diamine residue have a bent portion,
The bent part is a partial structure represented by the formula (1 ′) and a part represented by the formula (1 ′), the formula (2), the formula (4 ′), or the formula (5). A composition characterized in that it is at least one of partial structures other than the structure .




However, the symbol in a formula represents the following meaning.
X ² is a direct bond, a bond having a secondary or tertiary carbon atom, or an ether bond.
R ³ and R ⁴ are each independently a functional group selected from the group consisting of an alkyl group, an alkoxy group, an amino group, and a hydroxyl group. The alkyl group may have at least one substituent selected from the group consisting of a halogen atom, a cyano group, a nitro group and a sulfo group, and the alkoxy group is an alkyl group having 1 to 6 carbon atoms, It may have at least one substituent selected from the group consisting of a halogen atom, a cyano group, a nitro group, a sulfo group and an allyl group.   The composition of Claim 1 whose ratio of the tetracarboxylic acid residue which has the partial structure represented by the said Formula (4 ') in the said tetracarboxylic acid residue is 2 mol% or more and 95 mol% or less.   The ratio of the sum of the tetracarboxylic acid residue having a partial structure represented by the formula (1 ′) and the tetracarboxylic acid residue having a partial structure represented by the formula (2) in the tetracarboxylic acid residue Is 5 mol% or more and 95 mol% or less, The composition of Claim 1 or 2.   The composition according to any one of claims 1 to 3, wherein a ratio of the bent portion to a sum of the tetracarboxylic acid residue and the diamine residue is 0.1 mol% or more and 150 mol% or less.