TW201945437A - Polyimide resin, polyimide varnish, and polyimide film - Google Patents

Abstract

A polyfluorene imide resin having a constitutional unit A derived from a tetracarboxylic dianhydride and a constitutional unit B derived from a diamine, and the constitutional unit A includes a constitutional unit (A-1) derived from a compound represented by formula (a-1), The structural unit B includes a structural unit (B-1) derived from a compound represented by the formula (b-1) and a structural unit (B-2) derived from a compound represented by the formula (b-2); and the polyfluorene imide Resin polyimide varnish and polyimide film.

Description

Polyimide resin, polyimide varnish, and polyimide film

The present invention relates to a polyimide resin, a polyimide varnish, and a polyimide film.

Generally speaking, polyimide resins have excellent heat resistance, so various uses have been explored in fields such as electric-electronic parts. For example, based on the purpose of reducing the weight and flexibility of devices, it is expected that glass substrates used in image display devices such as liquid crystal displays and OLED displays will be replaced with plastic substrates. Research on polyimide films suitable for the plastic substrates is currently underway. In progress. Polyimide films for such applications require colorless transparency.

When a varnish coated on a glass support or a silicon wafer is heated and hardened to form a polyimide film, residual stress is generated in the polyimide film. If the residual stress of the polyimide film is large, the problem of warping of the glass support and the silicon wafer may occur, so the residual stress of the polyimide film is also required to be reduced.
Patent Document 1 discloses that 4,4'-oxodiphthalic dianhydride is used as a tetracarboxylic acid component, and α, ω-aminopropylpolydimethylsiloxane and a 4,4'-dioxane having a number average molecular weight of 1,000 are used. A polyimide resin obtained by synthesizing an amino diphenyl ether as a diamine component is used as a polyimide resin that provides a film with low residual stress.
[Previous Technical Literature]
[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2005-232383

[Questions to be solved by the invention]

As described above, polyimide films are required to have colorless transparency and low residual stress, but it is not easy to maintain excellent heat resistance while improving the above characteristics.
The present invention has been made in view of such a situation, and an object of the present invention is to provide a polyimide resin capable of forming a film having excellent heat resistance, colorless transparency, and low residual stress, and to provide a polyimide resin containing the polyimide resin. Imine varnish and polyimide film.
[Means for solving problems]

The inventors of the present case found that a polyimide resin containing a combination of specific constituent units can solve the above-mentioned problems, and completed the invention.

That is, the present invention relates to the following [1] to [12].
[1]
A polyfluorene imide resin having a constitutional unit A derived from a tetracarboxylic dianhydride and a constitutional unit B derived from a diamine,
This constitutional unit A includes a constitutional unit (A-1) derived from a compound represented by the following formula (a-1),
The constitutional unit B includes a constitutional unit (B-1) derived from a compound represented by the following formula (b-1), and a constitutional unit (B-2) derived from a compound represented by the following formula (b-2);
[Chemized 1]

In the formula (b-2), X is a single bond, a substituted or unsubstituted alkylene group, a carbonyl group, an ether group, a group represented by the following formula (b-2-i), or the following formula (b-2- ii) the base represented, p is an integer from 0 to 2, m1 is an integer from 0 to 4, and m2 is an integer from 0 to 4; however, when p is 0, m1 is an integer from 1 to 4;
［Chemical 2］

In formula (b-2-i), m3 is an integer of 0 to 5. In formula (b-2-ii), m4 is an integer of 0 to 5. In addition, m1 + m2 + m3 + m4 is 1 or more, p When it is 2, two X and two m2 to m4 are selected independently.

[2]
For example, the polyimide resin of [1], wherein the constituent unit (B-2) is a constituent unit (B-21) derived from a compound represented by the following formula (b-21);
［Chemical 3］

[3]
The polyfluorene imine resin according to [1] or [2], wherein the ratio of the constituent unit (A-1) in the constituent unit A is 40 mol% or more.
[4]
The polyimide resin according to any one of [1] to [3], wherein:
The ratio of the constituent unit (B-1) in the constituent unit B is 35 to 95 mol%,
The ratio of the constituent unit (B-2) in the constituent unit B is 5 to 65 mol%.
[5]
The polyimide resin according to any one of [1] to [4], wherein in the constituent unit B, the ratio of the constituent unit (B-1) to the constituent unit (B-2) [(B -1) / (B-2)] (mol / mol) is 35/65 to 95/5.
[6]
The polyimide resin according to any one of [1] to [5], wherein the constituent unit A further includes a constituent unit (A-2) derived from a compound represented by the following formula (a-2);
［Chemical 4］

[7]
The polyimide resin according to [6], wherein, in the constitutional unit A, the ratio of the constitutional unit (A-1) to the constitutional unit (A-2) [(A-1) / (A-2 )] (Mole / Mole) is 40/60 to 95/5.
[8]
The polyimide resin according to any one of [1] to [7], wherein the constituent unit A further comprises a constituent unit (A-3) derived from both terminal acid anhydride-modified polysiloxanes.
[9]
The polyimide resin according to [8], wherein, in the constitutional unit A, the ratio of the constitutional unit (A-1) to the constitutional unit (A-3) [(A-1) / (A-3 )] (Mol / mol) is 50/50 to 99/1.
[10]
A method for producing a polyfluorene imide resin, which comprises a tetracarboxylic acid component containing the compound represented by the above formula (a-1), a compound containing the compound represented by the above formula (b-1), and the above formula (b-2) The diamine component of the compound is heated in the presence of a reaction solvent to carry out amidation reaction.
[11]
A polyimide varnish is obtained by dissolving a polyimide resin according to any one of [1] to [9] in an organic solvent.
[12]
A polyimide film containing the polyimide resin according to any one of [1] to [9].
[Effect of Invention]

According to the present invention, a thin film having excellent heat resistance and colorless transparency and low residual stress can be formed.

[Polyimide resin]
The polyfluorene imide resin of the present invention has a constitutional unit A derived from a tetracarboxylic dianhydride and a constitutional unit B derived from a diamine. The constitutional unit A includes a constitutional unit (A-1) ), The structural unit B includes a structural unit (B-1) derived from a compound represented by the following formula (b-1), and a structural unit (B-2) derived from a compound represented by the following formula (b-2).
［Chemical 5］

(In formula (b-2), X is a single bond, a substituted or unsubstituted alkylene group, a carbonyl group, an ether group, a group represented by the following formula (b-2-i), or the following formula (b-2 -ii) represents a base, p is an integer of 0 to 2, m1 is an integer of 0 to 4, and m2 is an integer of 0 to 4. However, when p is 0, m1 is an integer of 1 to 4.)
［Chemical 6］

(In formula (b-2-i), m3 is an integer of 0 to 5; in formula (b-2-ii), m4 is an integer of 0 to 5. In addition, m1 + m2 + m3 + m4 is 1 or more, (When p is 2, two X and two m2 to m4 are selected independently.)
In the aforementioned formula, * represents a bonding site.

> Construction unit A>
The constitutional unit A is a constitutional unit derived from a tetracarboxylic dianhydride occupied in the polyfluorene imide resin, and includes a constitutional unit (A-1) derived from a compound represented by the following formula (a-1).
［Hua 7］

The compound represented by formula (a-1) is norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6,6 ''-tetrakis Carboxylic dianhydride.
When the constituent unit A includes the constituent unit (A-1), the colorless transparency and heat resistance of the film are improved.

The ratio of the constituent unit (A-1) in the constituent unit A is preferably 40 mol% or more, more preferably 50 mol% or more, and still more preferably 60 mol% or more. The upper limit value of the ratio of the constituent unit (A-1) is not particularly limited, that is, 100 mol%. The constituent unit A may be configured only by the constituent unit (A-1).

The constituent unit A may include constituent units other than the constituent unit (A-1).
The structural unit A preferably contains a structural unit (A-2) derived from a compound represented by the following formula (a-2) in addition to the structural unit (A-1).
［Chem 8］

The compound represented by the formula (a-2) is biphenyltetracarboxylic dianhydride (BPDA), and specific examples thereof can be enumerated: 3,3 ', 4,4'-biphenyltetracarboxylic acid represented by the following formula (a-2s) Acid dianhydride (s-BPDA), 2,3,3 ', 4'-biphenyltetracarboxylic dianhydride (a-BPDA), represented by the following formula (a-2i) 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride (i-BPDA).
［Hua 9］

When the constituting unit A includes the constituting unit (A-1) and the constituting unit (A-2), the ratio of the constituting unit (A-1) in the constituting unit A is preferably 40 to 95 mole%, and more preferably 50 to 90. Molar%, and more preferably 55 to 85 Molar%, and the ratio of the constituent unit (A-2) in the constituent unit A is preferably 5 to 60 Molar%, more preferably 10 to 50 Molar%, and more It is preferably 15 to 45 mol%.

When the constituent unit A includes the constituent unit (A-1) and the constituent unit (A-2), in the constituent unit A, the ratio of the constituent unit (A-1) to the constituent unit (A-2) [(A-1) / (A-2)] (Mole / Mole) is preferably 40/60 ～ 95/5, more preferably 50/50 ～ 90/10, still more preferably 55/45 ～ 85/15, and more It is preferably 55/45 to 70/30.

In the constituent unit A, the total ratio of the constituent units (A-1) and (A-2) is preferably 50 mol% or more, more preferably 70 mol% or more, and still more preferably 90 mol% or more. Preferably, it is more than 99 mol%. The upper limit value of the total ratio of the constituent units (A-1) and (A-2) is not particularly limited, that is, 100 mol%. The constituent unit A may be composed of only the constituent unit (A-1) and the constituent unit (A-2).

Since the constituent unit A further includes the constituent unit (A-2), the residual stress is further reduced.
In addition, since the constituent unit A further includes the constituent unit (A-2), the light transmittance of the film at a wavelength of 308 nm becomes small. In recent years, in regard to a method of peeling the support from the resin film in a support in which a resin film is laminated, a laser peeling process called laser lift-off (LASER LIFT-OFF; LLO) has attracted attention. The smaller the light transmittance at a wavelength of 308 nm, the better the laser peelability caused by the XeCl excimer laser at a wavelength of 308 nm.

In addition to the constitutional unit (A-1), the constitutional unit A preferably further comprises a constitutional unit (A-3) derived from acid anhydride-modified polysiloxane at both ends.
The aforementioned two-terminal acid anhydride-modified polysiloxane is preferably a compound represented by the following formula (a-3).
［Chem10］

(In formula (a-3),
R ¹ to R ⁶ are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms,
L ¹ and L ² are each independently a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms,
Z ¹ and Z ² are each independently a trivalent hydrocarbon group having 1 to 20 carbon atoms,
n is 1 to 200. )

R ¹ to R ⁶ in the formula (a-3) are each independently a monovalent hydrocarbon group having 1 to 20 carbon atoms.
Examples of the monovalent hydrocarbon group having 1 to 20 carbon atoms include an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and an aralkyl group having 7 to 20 carbon atoms. , An alkenyl group having 2 to 20 carbon atoms, and the like.
The alkyl group having 1 to 20 carbon atoms is preferably an alkyl group having 1 to 10 carbon atoms, and examples thereof include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, and third butyl. , Pentyl, and hexyl. The cycloalkyl group having 3 to 20 carbon atoms is preferably a cycloalkyl group having 3 to 10 carbon atoms, and examples thereof include cyclopentyl and cyclohexyl. The aryl group having 6 to 20 carbon atoms is preferably an aryl group having 6 to 10 carbon atoms, and examples thereof include a phenyl group and a naphthyl group. The aralkyl group having 7 to 20 carbon atoms is preferably an aralkyl group having 7 to 10 carbon atoms, and examples thereof include benzyl and phenethyl. The alkenyl group having 2 to 20 carbon atoms is preferably an alkenyl group having 2 to 10 carbon atoms, and examples thereof include vinyl, allyl, propenyl, isopropenyl, and butenyl.

R ¹ to R ⁶ are each independently selected from the group consisting of an alkyl group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, and an aralkyl group having 7 to 20 carbon atoms And an alkenyl group having 2 to 20 carbon atoms; more preferably selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, A group consisting of an aralkyl group having 7 to 10 carbon atoms and an alkenyl group having 2 to 10 carbon atoms; more preferably selected from the group consisting of an alkyl group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, And an alkenyl group having 2 to 10 carbon atoms; particularly preferably selected from the group consisting of methyl, ethyl, propyl, isopropyl, butyl, isobutyl, third butyl, pentyl, and hexyl , Phenyl, naphthyl, vinyl, allyl, propenyl, isopropenyl, and butenyl; preferably selected from the group consisting of methyl, ethyl, phenyl, and vinyl Group.

L ¹ and L ² in formula (a-3) are each independently a single bond or a divalent hydrocarbon group having 1 to 20 carbon atoms.
Examples of the divalent hydrocarbon group having 1 to 20 carbon atoms include an alkylene group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an arylene group having 6 to 20 carbon atoms.
The alkylene group having 1 to 20 carbon atoms is preferably an alkylene group having 1 to 10 carbon atoms, and examples thereof include methylene, ethylene, propyl, butyl, pentyl, and butyl. Jiji.
The cycloalkyl group having 3 to 20 carbon atoms is preferably a cycloalkyl group having 3 to 10 carbon atoms, and examples thereof include cyclobutyl, cyclopentyl, cyclohexyl, and cycloheptyl.
The arylene group having 6 to 20 carbon atoms is preferably an arylene group having 6 to 10 carbon atoms, and examples thereof include phenylene and naphthyl.

L ¹ and L ² are each independently selected from the group consisting of a single bond, an alkylene group having 1 to 20 carbon atoms, a cycloalkyl group having 3 to 20 carbon atoms, and an arylene group having 6 to 20 carbon atoms. Group; more preferably selected from the group consisting of a single bond, an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 3 to 10 carbon atoms, and an alkylene group having 6 to 10 carbon atoms; and more It is preferably selected from the group consisting of a single bond, an alkylene group having 1 to 10 carbon atoms, and an alkylene group having 6 to 10 carbon atoms; particularly preferably, it is selected from the group consisting of a single bond, methylene group, and ethylene group. Group consisting of phenyl, propyl, butyl, pentyl, hexanyl, phenyl, and naphthyl; preferably selected from the group consisting of a single bond, methylene, ethyl, and propyl , And a group consisting of phenylene.

Z ¹ and Z ² in the formula (a-3) are each independently a trivalent hydrocarbon group having 1 to 20 carbon atoms.
Z ¹ and Z ² are each independently selected from the group represented by the following formula (a-3-i), the group represented by the following formula (a-3-ii), and the following formula (a-3-iii) A group consisting of a base and a base represented by the following formula (a-3-iv).
In each formula, * represents a bonding site.
［Chem 11］

The group represented by formula (a-3-i) is a succinic acid residue, the group represented by formula (a-3-ii) is a phthalic acid residue, and the group represented by formula (a-3-iii) is 2,3- The norbornane dicarboxylic acid residue is represented by (a-3-iv) as a 5-norbornene-2,3-dicarboxylic acid residue.

N in the formula (a-3) is 1 to 200. n is preferably 3 to 150, and more preferably 5 to 120.

For those who can obtain it in the form of a commercially available product of both terminal acid anhydride-modified polysiloxanes, examples include "X22-168AS", "X22-168A", and "X22-168B" manufactured by Shin-Etsu Chemical Industry Co., Ltd. , "X22-168-P5-8", and "DMS-Z21" manufactured by Gelest.

When the constitutional unit A includes the constitutional unit (A-1) and the constitutional unit (A-3), the ratio of the constitutional unit (A-1) in the constitutional unit A is preferably 50 to 99 mol%, and more preferably 60 to 98. Molar%, and more preferably 70 to 97 Molar%, and the ratio of the constituent unit (A-3) in the constituent unit A is preferably 1 to 50 Molar%, more preferably 2 to 40 Molar%, and more It is preferably 3 to 30 mol%.

When the constituent unit A includes the constituent unit (A-1) and the constituent unit (A-3), in the constituent unit A, the ratio of the constituent unit (A-1) to the constituent unit (A-3) [(A-1) / (A-3)] (Mole / Mole) is preferably 50/50 ～ 99/1, more preferably 60/40 ～ 98/2, more preferably 70/30 ～ 97/3, and more It is preferably 80/20 to 95/5.

In the constituent unit A, the total ratio of the constituent units (A-1) and (A-3) is preferably 50 mol% or more, more preferably 70 mol% or more, and still more preferably 90 mol% or more. Preferably, it is more than 99 mol%. The upper limit value of the total ratio of the constituent units (A-1) and (A-3) is not particularly limited, that is, 100 mol%. The constituent unit A may be composed of only the constituent unit (A-1) and the constituent unit (A-3).

Since the constituent unit A further includes the constituent unit (A-3), the residual stress of the film can be kept low and the colorless transparency can be improved.

The constituent unit A preferably includes both the constituent unit (A-2) and the constituent unit (A-3) in addition to the constituent unit (A-1).
When the constituting unit A includes the constituting unit (A-1), the constituting unit (A-2), and the constituting unit (A-3), the ratio of the constituting unit (A-1) in the constituting unit A should preferably be 50 to 90 moles. Ear%, more preferably 60 to 85 mole%, and more preferably 65 to 80 mole%, and the ratio of the constituent unit (A-2) in the constituent unit A should be 5 to 30 mole%, more preferably 5 to 25 mol%, and more preferably 5 to 20 mol%, and the ratio of the constituent unit (A-3) in the component A is preferably 1 to 25 mol%, and more preferably 2 to 20 mol% , And more preferably 3 to 15 mole%.

When the constituent unit A includes the constituent unit (A-1), the constituent unit (A-2), and the constituent unit (A-3), in the constituent unit A, the constituent unit (A-2) and the constituent unit (A-3) ) The ratio [(A-2) / (A-3)] (Mole / Mole) is preferably 17/83 to 97/3, more preferably 20/80 to 93/7, and even more preferably 25 / 75 to 87/13, and even more preferably 55/45 to 87/13.

In the constituent unit A, the total ratio of the constituent units (A-1) to (A-3) is preferably 50 mol% or more, more preferably 70 mol% or more, and still more preferably 90 mol% or more. Preferably, it is more than 99 mol%. The upper limit of the total ratio of the constituent units (A-1) to (A-3) is not particularly limited, that is, 100 mol%. The constituent unit A may be composed of only the constituent unit (A-1), the constituent unit (A-2), and the constituent unit (A-3).

The constituent units other than the constituent unit (A-1) arbitrarily contained in the constituent unit A are not limited to the constituent units (A-2) and (A-3). The tetracarboxylic dianhydride which provides such an arbitrary structural unit is not specifically limited, A pyromellitic dianhydride, 9,9'-bis (3,4- dicarboxyphenyl) fluorin dianhydride, and 4 are mentioned. , 4 '-(hexafluoroisopropylidene) diphthalic anhydride and other aromatic tetracarboxylic dianhydrides; 1,2,3,4-cyclobutane tetracarboxylic dianhydride and 1,2,4,5-cyclo Alicyclic tetracarboxylic dianhydrides such as hexanetetracarboxylic dianhydride (but not including compounds represented by formula (a-1)); and aliphatics such as 1,2,3,4-butanetetracarboxylic dianhydride Tetracarboxylic dianhydride.
In addition, in this specification, an aromatic tetracarboxylic dianhydride means a tetracarboxylic dianhydride containing one or more aromatic rings, and an alicyclic tetracarboxylic dianhydride means an aromatic tetracarboxylic dianhydride containing one or more alicyclic rings and does not contain an aromatic The cyclic tetracarboxylic dianhydride and the aliphatic tetracarboxylic dianhydride mean a tetracarboxylic dianhydride containing neither an aromatic ring nor an alicyclic ring.
The number of constituent units other than the constituent unit (A-1) arbitrarily contained in the constituent unit A may be one or two or more.

> Construction unit B>
The constitutional unit B is a constitutional unit derived from a diamine in the polyfluorene imide resin, and includes a constitutional unit (B-1) derived from a compound represented by the following formula (b-1), and a constitutional unit (B-2) The constituent unit (B-2) of the compound shown.
［Hua 12］

(In formula (b-2), X is a single bond, a substituted or unsubstituted alkylene group, a carbonyl group, an ether group, a group represented by the following formula (b-2-i), or the following formula (b-2 -ii) represents a base, p is an integer of 0 to 2, m1 is an integer of 0 to 4, and m2 is an integer of 0 to 4. However, when p is 0, m1 is an integer of 1 to 4.)
［Chemical 13］

(In formula (b-2-i), m3 is an integer of 0 to 5; in formula (b-2-ii), m4 is an integer of 0 to 5. In addition, m1 + m2 + m3 + m4 is 1 or more, (When p is 2, two X and two m2 to m4 are selected independently.)
In the aforementioned formula, * represents a bonding site.

The compound represented by formula (b-1) is 2,2'-bis (trifluoromethyl) benzidine.
By including the constitutional unit (B-1) in the constitutional unit B, the colorless transparency of the film is improved, and the residual stress is reduced.

Specific examples of the compound represented by the formula (b-2) include compounds represented by the following formulae (b-21) to (b-27).

［Chem 14］

Specific examples of the compound represented by the formula (b-21) include a compound represented by the following formula (b-211), that is, 3,5-diaminobenzoic acid.
[Chemized 15]

The constituent unit (B-2) is preferably a constituent unit (B-21) derived from a compound represented by the formula (b-21), and more preferably a constituent unit (B-211) derived from a compound represented by the formula (b-211).

When the constituent unit B includes the constituent unit (B-2), the heat resistance of the film is improved.

The ratio of the constituent unit (B-1) in the constituent unit B is preferably 35 to 95 mol%, more preferably 40 to 90 mol%, and still more preferably 45 to 85 mol%.
The ratio of the constituent unit (B-2) in the constituent unit B is preferably 5 to 65 mol%, more preferably 10 to 60 mol%, and still more preferably 15 to 55 mol%.

In the constituent unit B, the ratio of the constituent unit (B-1) to the constituent unit (B-2) [(B-1) / (B-2)] (mol / mol) is preferably 35/65 to 95 / 5, more preferably 40/60 to 90/10, still more preferably 45/55 to 85/15, and still more preferably 45/55 to 70/30.

In the constituent unit B, the total ratio of the constituent units (B-1) and (B-2) is preferably 50 mol% or more, more preferably 70 mol% or more, and still more preferably 90 mol% or more. Preferably, it is more than 99 mol%. The upper limit value of the total ratio of the constituent units (B-1) and (B-2) is not particularly limited, that is, 100 mol%. The constituent unit B may be composed of only the constituent unit (B-1) and the constituent unit (B-2).

The constituent unit B may include constituent units other than the constituent units (B-1) and (B-2). The diamine providing such a structural unit is not particularly limited, and examples thereof include 1,4-phenylenediamine, p-xylylenediamine, 1,5-diaminonaphthalene, and 2,2'-dimethylbiphenyl. -4,4'-diamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 2,2-bis (4-aminophenyl) hexafluoropropane , 4,4'-diaminodiphenylphosphonium, 4,4'-diaminophenhydrazone, 1- (4-aminophenyl) -2,3-dihydro-1,3,3 -Trimethyl-1H-inden-5-amine, α, α'-bis (4-aminophenyl) -1,4-diisopropylbenzene, N, N'-bis (4-aminobenzene Group) p-xylylenediamine, 4,4'-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2 Aromatic diamines such as 2,2- (4- (4-aminophenoxy) phenyl) hexafluoropropane, and 9,9-bis (4-aminophenyl) fluorene (but not including formula (b -1) and compounds represented by formula (b-2)); 1,3-bis (aminomethyl) cyclohexane and 1,4-bis (aminomethyl) cyclohexane and other alicyclic rings Diamines; and aliphatic diamines such as ethylenediamine and hexamethylenediamine.
In addition, in the present specification, an aromatic diamine means a diamine containing one or more aromatic rings, and an alicyclic diamine means a diamine containing one or more alicyclic rings and no aromatic ring, and an aliphatic diamine. It means a diamine containing neither an aromatic ring nor an alicyclic ring.
The constituent units other than the constituent units (B-1) and (B-2) arbitrarily contained in the constituent unit B may be one type, or two or more types.

The number average molecular weight of the polyimide resin of the present invention is preferably 5,000 to 300,000, more preferably 5,000 to 100,000, in view of the mechanical strength of the obtained polyimide film. The number average molecular weight of the polyfluorene imine resin can be obtained, for example, from a standard polymethyl methacrylate (PMMA) conversion value measured by gel filtration chromatography.

The polyfluorene imide resin of the present invention may contain a structure other than a polyfluorene imine chain (a structure in which the structural unit A and the structural unit B are bonded to each other through the fluorene imine). Examples of the structure other than the polyfluorene chain which may be contained in the polyfluorene imine resin include a structure containing a fluorene bond.
The polyfluorene imide resin of the present invention preferably contains a polyfluorene imine chain (a structure in which the structural unit A and the structural unit B are bonded by the fluorene imine) as a main structure. Therefore, the ratio of the polyfluorene imine chain to the polyfluorine resin of the present invention is preferably 50% by mass or more, more preferably 70% by mass or more, still more preferably 90% by mass or more, particularly preferably 99%. Above mass%.

By using the polyfluorene imide resin of the present invention, a film excellent in heat resistance, colorless transparency, and low residual stress can be formed. The ideal physical properties of the film are as follows.

The glass transition temperature (Tg) is preferably 380 ° C or higher, more preferably 400 ° C or higher, still more preferably 450 ° C or higher, and still more preferably 470 ° C or higher.
As far as the total light transmittance is concerned, when making a film with a thickness of 10 μm, it is preferably 88% or more, more preferably 89% or more, and even more preferably 90% or more.
In terms of the yellow index (YI), when a thin film having a thickness of 10 μm is used, it is preferably 5.0 or less, more preferably 4.0 or less, still more preferably 3.0 or less, and still more preferably 2.0 or less.
The residual stress is preferably 25.0 MPa or less, more preferably 20.0 MPa or less, and still more preferably 15.0 MPa or less.

In addition, by using a polyimide resin, which is one aspect of the present invention, that is, the constitutional unit A further comprises a polyimide resin having a constitutional unit (A-2), and a film having excellent laser peeling properties can be further formed. The ideal physical properties of the film are as follows.
In terms of light transmittance at a wavelength of 308 nm, when making a thin film having a thickness of 10 μm, it is preferably 0.8% or less, more preferably 0.6% or less, and still more preferably 0.4% or less.

In addition, the film that can be formed using the polyfluorene imide resin of the present invention also has good mechanical properties and has the following ideal physical property values.
The tensile elastic modulus is preferably 2.0 GPa or more, more preferably 3.0 GPa or more, and still more preferably 4.0 GPa or more.
The tensile strength is preferably 80 MPa or more, more preferably 100 MPa or more, still more preferably 120 MPa or more, and still more preferably 150 MPa or more.
In addition, the said physical-property value of this invention can be specifically measured by the method as described in an Example.

[Manufacturing method of polyimide resin]
The polyimide resin of the present invention can be obtained by providing a tetracarboxylic acid component containing a compound providing the above-mentioned constitutional unit (A-1), a compound containing the above-mentioned constitutional unit (B-1), and providing the above-mentioned constitutional unit ( It is produced by reacting the diamine component of the compound of B-2).
A more specific method for producing a polyimide resin according to the present invention is to provide a tetracarboxylic acid component including a compound providing a structural unit (A-1), a compound including a providing a structural unit (B-1), and providing the above-mentioned composition. The diamine component of the compound of the unit (B-2) is heated in the presence of a reaction solvent to carry out the amidine imidization reaction.
In addition, a more preferred method for producing the polyfluorene imine resin of the present invention includes a tetracarboxylic acid component containing a compound represented by formula (a-1), and a compound containing a compound represented by formula (b-1) and a formula The diamine component of the compound represented by (b-2) is heated in the presence of a reaction solvent to carry out the amidine imidization reaction.

As a compound which provides a structural unit (A-1), the compound represented by Formula (a-1) can be mentioned, It is not limited to this, As long as the same structural unit can be provided, it can also be its derivative. Examples of the derivative include a tetracarboxylic acid corresponding to a tetracarboxylic dianhydride represented by the formula (a-1) (that is, norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ' '-Norbornane-5,5' ', 6,6' '-tetracarboxylic acid), and alkyl esters of the tetracarboxylic acid. The compound providing the constituent unit (A-1) is preferably a compound represented by the formula (a-1) (that is, dianhydride).

The tetracarboxylic acid component preferably contains 40 mol% or more of the compound providing the constituent unit (A-1), more preferably 50 mol% or more, and even more preferably 60 mol% or more. The upper limit of the content of the compound providing the constituent unit (A-1) is not particularly limited, that is, 100 mol%. The tetracarboxylic acid component may be composed of only the compound providing the constituent unit (A-1).

The tetracarboxylic acid component may include a compound other than the compound which provides a structural unit (A-1).
The tetracarboxylic acid component preferably contains a compound providing a structural unit (A-2) in addition to the compound providing a structural unit (A-1).
As a compound which provides a structural unit (A-2), the compound represented by Formula (a-2) is mentioned, However, It is not limited to this, As long as the same structural unit can be provided, it may be its derivative. Examples of the derivative include a tetracarboxylic acid corresponding to a tetracarboxylic dianhydride represented by the formula (a-2) and an alkyl ester of the tetracarboxylic acid. The compound providing the constituent unit (A-2) is preferably a compound represented by the formula (a-2) (that is, dianhydride).

When the tetracarboxylic acid component includes the compound providing the structural unit (A-1) and the compound providing the structural unit (A-2), the tetracarboxylic acid component should preferably contain 40 to 95 mole% of the providing structural unit (A-1). The compound more preferably contains 50 to 90 mole%, more preferably 55 to 85 mole%, and more preferably 5 to 60 mole% of the compound providing the constituent unit (A-2), and more preferably contains 10 to 50 mol%, and more preferably 15 to 45 mol%.
When the tetracarboxylic acid component includes the compound providing the structural unit (A-1) and the compound providing the structural unit (A-2), in the tetracarboxylic acid component, the compound providing the structural unit (A-1) and the structural unit ( The ratio of the compounds in A-2) [(A-1) / (A-2)] (Mole / Mole) is preferably 40/60 to 95/5, more preferably 50/50 to 90/10, and It is more preferably 55/45 to 85/15, and still more preferably 55/45 to 70/30.

The tetracarboxylic acid component preferably contains a compound providing the constituent unit (A-1) and a compound providing the constituent unit (A-2) in a total amount of 50 mol% or more, more preferably 70 mol% or more, and more preferably Above 90 mol%, it is particularly preferred to contain above 99 mol%. The upper limit of the total content of the compound providing the constituent unit (A-1) and the compound providing the constituent unit (A-2) is not particularly limited, that is, 100 mol%. The tetracarboxylic acid component may be composed of only the compound providing the structural unit (A-1) and the compound providing the structural unit (A-2).

The tetracarboxylic acid component preferably contains a compound providing a structural unit (A-3) in addition to the compound providing a structural unit (A-1).
Examples of the compound that provides the structural unit (A-3) include both end-anhydride-modified polysiloxanes (for example, compounds represented by the formula (a-3)). May be its derivative. Examples of the derivative include a tetracarboxylic acid corresponding to both terminal anhydride-modified polysiloxanes and an alkyl ester of the tetracarboxylic acid. The compound providing the constituent unit (A-3) is preferably an acid anhydride-modified polysiloxane (ie, a dianhydride) at both ends.

When the tetracarboxylic acid component includes the compound providing the structural unit (A-1) and the compound providing the structural unit (A-3), the tetracarboxylic acid component should preferably contain 50 to 99 mol% of the providing structural unit (A-1). The compound more preferably contains 60 to 98 mole%, more preferably 70 to 97 mole%, and more preferably 1 to 50 mole% of the compound providing the constituent unit (A-3), and more preferably contains 2 to 40 mol%, and more preferably 3 to 30 mol%.
When the tetracarboxylic acid component includes the compound providing the structural unit (A-1) and the compound providing the structural unit (A-3), in the tetracarboxylic acid component, the compound providing the structural unit (A-1) and the providing structural unit ( The ratio of the compound of A-3) [(A-1) / (A-3)] (mol / mol) is preferably 50/50 ～ 99/1, more preferably 60/40 ～ 98/2, and It is more preferably 70/30 to 97/3, and even more preferably 80/20 to 95/5.

The tetracarboxylic acid component preferably contains a compound providing the constituent unit (A-1) and a compound providing the constituent unit (A-3) in a total amount of 50 mol% or more, more preferably 70 mol% or more, and more preferably Above 90 mol%, it is particularly preferred to contain above 99 mol%. The upper limit of the total content of the compound providing the constituent unit (A-1) and the compound providing the constituent unit (A-3) is not particularly limited, that is, 100 mol%. The tetracarboxylic acid component may be composed only of the compound providing the structural unit (A-1) and the compound providing the structural unit (A-3).

The tetracarboxylic acid component preferably contains both the compound providing the structural unit (A-1) and the compound providing the structural unit (A-2) and the compound providing the structural unit (A-3).
When the tetracarboxylic acid component includes the compound providing the structural unit (A-1), the compound providing the structural unit (A-2), and the compound providing the structural unit (A-3), the tetracarboxylic acid component should preferably contain 50 to 90 moles. The compound providing the constituent unit (A-1) is preferably 60 to 85 mole%, more preferably 65 to 80 mole%, and preferably 5 to 30 mole%. The compound of (A-2) more preferably contains 5 to 25 mol%, still more preferably contains 5 to 20 mol%, and further preferably contains 1 to 25 mol% of the provided constituent unit (A-3). The compound more preferably contains 2 to 20 mole%, and still more preferably contains 3 to 15 mole%.
When the tetracarboxylic acid component includes a compound that provides the structural unit (A-1), a compound that provides the structural unit (A-2), and a compound that provides the structural unit (A-3), the tetracarboxylic acid component provides the structural unit The ratio of the compound of (A-2) to the compound providing the constituent unit (A-3) [(A-2) / (A-3)] (mol / mol) is preferably 17/83 to 97/3, It is more preferably 20/80 to 93/7, still more preferably 25/75 to 87/13, and even more preferably 55/45 to 87/13.

The tetracarboxylic acid component preferably contains a compound providing the constituent unit (A-1), a compound providing the constituent unit (A-2), and a compound providing the constituent unit (A-3) in a total amount of 50 mol% or more, more preferably Contains 70 mol% or more, more preferably 90 mol% or more, and particularly preferably 99 mol% or more. The upper limit of the total content of the compound providing the constituent unit (A-1), the compound providing the constituent unit (A-2), and the compound providing the constituent unit (A-3) is not particularly limited, that is, 100 mol %. The tetracarboxylic acid component may be composed only of the compound providing the structural unit (A-1) and the compound providing the structural unit (A-2) and the compound providing the structural unit (A-3).

The compound other than the compound providing the constituent unit (A-1) arbitrarily contained in the tetracarboxylic acid component is not limited to the compound providing the constituent unit (A-2) and the compound providing the constituent unit (A-3). Examples of such arbitrary compounds include the above-mentioned aromatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, and aliphatic tetracarboxylic dianhydrides, and their derivatives (tetracarboxylic acids and alkyl esters of tetracarboxylic acids) Wait).
The compound other than the compound providing the structural unit (A-1) arbitrarily contained in the tetracarboxylic acid component may be one type, or two or more types.

As a compound which provides a structural unit (B-1), the compound represented by Formula (b-1) is mentioned, However, It is not limited to this, As long as it can provide the same structural unit, its derivative may be sufficient. Examples of the derivative include a diisocyanate corresponding to a diamine represented by the formula (b-1). The compound providing the constituent unit (B-1) is preferably a compound represented by the formula (b-1) (that is, a diamine).
Similarly, as the compound providing the structural unit (B-2), a compound represented by the formula (b-2) may be mentioned, but it is not limited thereto, and may be a derivative thereof as long as the same structural unit can be provided. Examples of the derivative include a diisocyanate corresponding to a diamine represented by the formula (b-2). The compound providing the constituent unit (B-2) is preferably a compound represented by the formula (b-2) (that is, a diamine).

The diamine component preferably contains 35 to 95 mole% of the compound providing the constituent unit (B-1), more preferably contains 40 to 90 mole%, and even more preferably contains 45 to 85 mole%.
The diamine component preferably contains 5 to 65 mol% of the compound providing the constituent unit (B-2), more preferably 10 to 60 mol%, and even more preferably 15 to 55 mol%.
In the diamine component, the ratio [(B-1) / (B-2)] (mol / mol) of the compound providing the constituent unit (B-1) to the compound providing the constituent unit (B-2) is preferably It is 35/65 to 95/5, more preferably 40/60 to 90/10, still more preferably 45/55 to 85/15, and still more preferably 45/55 to 70/30.

The diamine component preferably contains a compound providing the constituent unit (B-1) and a compound providing the constituent unit (B-2) in a total amount of 50 mol% or more, more preferably 70 mol% or more, and more preferably 90 Molar% or more, particularly preferably, it contains 99 Mole% or more. The upper limit of the total content of the compound providing the constituent unit (B-1) and the compound providing the constituent unit (B-2) is not particularly limited, that is, 100 mol%. The diamine component may be composed only of the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2).

The diamine component may include a compound other than the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2). Examples of the compound include the aforementioned aromatic diamines, alicyclic diamines, and Aliphatic diamines and their derivatives (diisocyanates, etc.).
The compound other than the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2) arbitrarily contained in the diamine component may be one type, or two or more types.

In the present invention, in terms of the addition ratio of the tetracarboxylic acid component and the diamine component used in the production of the polyfluorene imide resin, the diamine component is preferably 0.9 to 1.1 moles relative to the 1 mole of the tetracarboxylic acid component. .

In addition, in the present invention, in the production of the polyfluorene imide resin, in addition to the tetracarboxylic acid component and the diamine component described above, a blocking agent may be used. The capping agent is preferably a monoamine or a dicarboxylic acid. In terms of the amount of the capping agent introduced, it is preferably 0.0001 to 0.1 mol, and more preferably 0.001 to 0.06 mol relative to 1 mol of the tetracarboxylic acid component. Monoamine-based capping agents are recommended, for example: methylamine, ethylamine, propylamine, butylamine, benzylamine, 4-methylbenzylamine, 4-ethylbenzylamine, 4-dodecylbenzylamine, 3-methyl Benzylamine, 3-ethylbenzylamine, aniline, 3-methylaniline, 4-methylaniline and the like. Among these, benzylamine and aniline are preferably used. The dicarboxylic acid-type end-capping agent is preferably a dicarboxylic acid-type, and a part of it may form a ring closure. For example recommended: phthalic acid, phthalic anhydride, 4-chlorophthalic acid, tetrafluorophthalic acid, 2,3-benzophenone dicarboxylic acid, 3,4-benzophenone dicarboxylic acid, cyclohexane-1, 2-dicarboxylic acid, cyclopentane-1,2-dicarboxylic acid, 4-cyclohexene-1,2-dicarboxylic acid, and the like. Among these, phthalic acid and phthalic anhydride can be preferably used.

The method of reacting the tetracarboxylic acid component and the diamine component is not particularly limited, and a known method can be used.
Specific reaction methods include: (1) adding a tetracarboxylic acid component, a diamine component, and a reaction solvent to a reactor, and stirring at room temperature to 80 ° C for 0.5 to 30 hours, and then heating and performing a sulfonimidization reaction Method: (2) After adding the diamine component and the reaction solvent to the reactor and dissolving them, add the tetracarboxylic acid component, and stir at room temperature to 80 ° C for 0.5 to 30 hours as needed, and then raise the temperature and carry out the dialysis A method of amination reaction; (3) a method of adding a tetracarboxylic acid component, a diamine component, and a reaction solvent to a reactor, directly heating up, and performing an amidation reaction.

The reaction solvent used in the production of the polyfluorene imine resin may be any one that can dissolve the polyfluorene imine that does not interfere with the fluorene imidization reaction. Examples include aprotic solvents, phenol-based solvents, ether-based solvents, and carbonate-based solvents.

Specific examples of the aprotic solvent include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, Ammonium solvents such as 1,3-dimethylimidazolidone and tetramethylurea; lactone solvents such as γ-butyrolactone and γ-valerolactone; hexamethylphosphonium amine and hexamethylphosphine Phosphonium-containing solvents such as fluorene and amines; sulfur-containing solvents such as dimethyl fluorene, dimethyl fluorene, and cyclobutane; ketone solvents such as acetone, cyclohexanone, and methylcyclohexanone; methylpyridine And amine solvents such as pyridine, and ester solvents such as acetic acid (2-methoxy-1-methylethyl).

Specific examples of the phenol-based solvent include phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, and 2,6 -Xylenol, 3,4-xylenol, 3,5-xylenol and the like.
Specific examples of the ether-based solvent include 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, 1,2-bis (2-methoxyethoxy) ethane, Bis [2- (2-methoxyethoxy) ethyl] ether, tetrahydrofuran, 1,4-dioxane and the like.
Specific examples of the carbonate-based solvent include diethyl carbonate, ethyl methyl carbonate, ethyl acetate, and propyl carbonate.
Among the above-mentioned reaction solvents, a fluorene-based solvent or a lactone-based solvent is preferred. Moreover, the said reaction solvent can also be used individually or in mixture of 2 or more types.

As for the amidine imidization reaction, it is preferable to use a Dean-Stark apparatus and the like to perform the reaction while removing water generated during the production. By performing such operations, the degree of polymerization and the rate of imidization can be further improved.

In the above fluorene imidization reaction, a known fluorene imidization catalyst can be used. Examples of the sulfonium imidization catalyst include an alkali catalyst and an acid catalyst.
Examples of the base catalyst include pyridine, quinoline, isoquinoline, α-methylpyridine, β-methylpyridine, 2,4-dimethylpyridine, 2,6-dimethylpyridine, trimethylamine, and triethyl Organic base catalysts such as amine, tripropylamine, tributylamine, triethylenediamine, imidazole, N, N-dimethylaniline, N, N-diethylaniline; potassium hydroxide, sodium hydroxide, potassium carbonate , Sodium carbonate, potassium bicarbonate, sodium bicarbonate and other inorganic base catalysts.
Examples of the acid catalyst include crotonic acid, acrylic acid, trans-3-hexenoic acid, cinnamic acid, benzoic acid, methylbenzoic acid, hydroxybenzoic acid, terephthalic acid, benzenesulfonic acid, p-toluenesulfonic acid, Naphthalenesulfonic acid and so on. The above sulfonium imidization catalysts can be used alone or in combination of two or more.
Among the above, considering the operational point of view, it is preferable to use an alkali catalyst, more preferably an organic base catalyst, and more preferably triethylamine, and a particularly good combination of triethylamine and triethylenediamine.

From the viewpoint of the reaction temperature of the sulfonium imidization, considering the reaction rate and the inhibition of gelation, the temperature is preferably 120 to 250 ° C, and more preferably 160 to 200 ° C. In addition, the reaction time is preferably 0.5 to 10 hours from the start of distillative production of water.

[Polyimide varnish]
The polyimide varnish of the present invention is obtained by dissolving the polyimide resin of the present invention in an organic solvent. That is, the polyimide varnish of the present invention contains the polyimide resin of the present invention and an organic solvent, and the polyimide resin is soluble in the organic solvent.
The organic solvent is not particularly limited as long as it dissolves the polyfluorene imine resin, and it is preferable to use the above-mentioned compounds as a reaction solvent used when preparing the polyfluorene imine resin alone or in combination of two or more kinds.
Specific examples of the organic solvent include aprotic solvents, phenol-based solvents, ether-based solvents, carbonate-based solvents, and the like, and aprotic solvents are preferred.
Examples of the aprotic solvent include a fluorene-based solvent, a lactone-based solvent, a phosphorus-based amine-based solvent, a sulfur-containing solvent, a ketone-based solvent, an amine-based solvent, and an ester-based solvent. A solvent is preferable, and a lactone-based solvent is more preferable.
Examples of the amidine solvents include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 1,3- Dimethylimidazolidone, tetramethylurea and the like. Examples of the lactone-based solvent include γ-butyrolactone and γ-valerolactone.
The polyimide varnish of the present invention may be a polyimide solution obtained by dissolving a polyimide resin obtained by a polymerization method in a reaction solvent, or may further be a diluted solvent for the polyimide solution. Successor.

The polyimide resin of the present invention has solvent solubility, so it can be made into a stable, high-concentration varnish at room temperature. The polyimide varnish of the present invention preferably contains 5-40% by mass of the polyimide resin of the present invention, more preferably 5-30% by mass, and even more preferably 10-30% by mass. The viscosity of the polyimide varnish is preferably 1 to 200 Pa ･ s, more preferably 1 to 150 Pa ･ s, and even more preferably 5 to 150 Pa ･ s. The viscosity of the polyimide varnish is a value obtained by measuring at 25 ° C using an E-type viscometer.
In addition, the polyimide varnish of the present invention may contain an inorganic filler, an adhesion promoter, a release agent, a flame retardant, an ultraviolet stabilizer, and an interface within a range that does not impair the required characteristics of the polyimide film. Various additives such as active agent, leveling agent, defoaming agent, fluorescent whitening agent, crosslinking agent, polymerization initiator, photosensitizer, etc.
The manufacturing method of the polyimide varnish of this invention is not specifically limited, A well-known method can be used.

[Polyimide film]
The polyimide film of the present invention contains the polyimide resin of the present invention. Therefore, the polyimide film of the present invention is excellent in heat resistance and colorless transparency, and has low residual stress. The ideal physical properties of the polyimide film of the present invention are as described above.
The method for producing the polyfluorene imide film of the present invention is not particularly limited, and a known method can be used. For example, the polyimide varnish of the present invention is coated or formed into a thin film on a smooth support such as a glass plate, a metal plate, or a plastic, and then the reaction solvent contained in the varnish is removed by heating and diluted. Methods of organic solvents such as solvents. On the surface of the support, a release agent may also be applied in advance if necessary.
The method of removing the organic solvent contained in the varnish by heating is preferably the following method. That is, it is preferable to evaporate the organic solvent at a temperature below 120 ° C to make a self-supporting film, then peel the self-supporting film from the support, fix the end of the self-supporting film, and use the organic solvent in the It is dried at a temperature above the boiling point to produce a polyimide film. In addition, it is preferable to perform drying under a nitrogen environment. The pressure in the dry environment may be any of reduced pressure, normal pressure, and increased pressure. The heating temperature when the self-supporting film is dried to produce a polyimide film is not particularly limited, but is preferably 200 to 400 ° C.

Moreover, the polyimide film of this invention can also be manufactured using the polyamine varnish which melt | dissolved the polyamic acid in the organic solvent.
The polyamino acid contained in the polyamino acid varnish is a precursor of the polyamido resin of the present invention, and is a tetracarboxylic acid component containing a compound providing the above-mentioned constitutional unit (A-1), and containing the above-mentioned structure. Addition polymerization product of the compound of the unit (B-1) and the diamine component which provides the compound of the above-mentioned constituent unit (B-2). The polyimide resin (dehydration ring-closing) of the polyamidic acid can be obtained as a final product, which is the polyimide resin of the present invention.
As the organic solvent contained in the aforementioned polyamic acid varnish, the organic solvent contained in the polyfluorine varnish of the present invention can be used.
In the present invention, the polyamic acid varnish may be a tetracarboxylic acid component containing a compound providing the above-mentioned constitutional unit (A-1), a compound containing the above-mentioned constitutional unit (B-1), and The diamine component of the compound 2) is a polyamic acid solution itself obtained by addition polymerization reaction in a reaction solvent, or may be obtained by further adding a diluted solvent to the polyamino acid solution.

The method for producing a polyimide film using a polyamic acid varnish is not particularly limited, and a known method can be used. For example, a polyamic acid varnish can be coated or formed into a thin film on a smooth support such as a glass plate, a metal plate, or a plastic, and the organic solvent such as a reaction solvent and a diluent solvent contained in the varnish can be removed by heating. A polyfluorinated acid film is obtained, and then the polyfluorinated acid in the polyfluorinated acid film is fluorinated by heating to produce a polyfluorinated film.
The heating temperature when the polyamic acid varnish is dried to obtain a polyamino acid film is preferably 50 to 120 ° C. The heating temperature when the polyimide acid is subjected to ammonium imidization by heating is preferably 200 to 400 ° C.
In addition, the method of amidine imidization is not limited to thermal amidine imidization, and chemical amidine imidization may also be used.

The thickness of the polyimide film according to the present invention can be appropriately selected depending on the application and the like, and is preferably 1 to 250 μm, more preferably 5 to 100 μm, still more preferably 8 to 80 μm, and still more preferably 10 to 80 μm. . With a thickness of 1 to 250 μm, it can be practically used as a self-supporting film.
The thickness of the polyimide film can be easily controlled by adjusting the solid content concentration and viscosity of the polyimide varnish.

The polyimide film of the present invention can be preferably used as a film for various members such as color filters, flexible displays, semiconductor parts, and optical members. The polyimide film of the present invention is particularly preferably used as a substrate for an image display device such as a liquid crystal display or an OLED display.
[Example]

Hereinafter, the present invention will be specifically described by way of examples. However, the present invention is not limited to these examples.
The solid content concentrations of the varnishes obtained in the examples and comparative examples and the physical properties of the films were measured by the methods shown below.

(1) Solid content concentration The solid content concentration of the varnish is measured by using a small electric furnace "MMF-1" manufactured by AS ONE Co., Ltd. to heat the sample at 320 ° C for 120 min. The difference in mass is calculated.
(2) Film thickness The film thickness was measured using a micrometer manufactured by Mitutoyo Corporation.
(3) Total light transmittance, yellow index (YI) (evaluation of colorless transparency)
The total light transmittance and YI are measured in accordance with JIS K7361-1: 1997 using a simultaneous color-turbidity measuring device "COH400" manufactured by Nippon Denshoku Industries Co., Ltd. The closer the total light transmittance is to 100% and the smaller the value of YI, the better the colorless transparency.
(4) Glass transition temperature (Tg) (evaluation of heat resistance)
Using a thermomechanical analysis device "TMA / SS6100" manufactured by Hitachi High-Tech Science Co., Ltd., the temperature was increased sufficiently in the tensile mode under the conditions of a sample size of 2 mm x 20 mm, a load of 0.1 N, and a heating rate of 10 ° C / min. The temperature of the residual stress is removed to remove the residual stress, and then it is cooled to room temperature. Then, the elongation of the test piece was measured under the same conditions as the aforementioned treatment for removing residual stress, and the place where the inflection point of the elongation appeared was the glass transition temperature. The larger the value of Tg, the more excellent the heat resistance.
(5) Residual stress Coating polyimide varnish or polyamic acid varnish with a spin coater was used to measure the thickness of the "warpage" using a residual stress measuring device "FLX-2320" made by KLA-Tencor Corporation in advance. 525μm ± 25μm on a 4-inch silicon wafer and pre-baked. Then, a hot air dryer was used to perform a heat hardening treatment at 400 ° C. for 1 hour in a nitrogen environment to obtain a silicon wafer with a polyimide film having a thickness of 8 to 20 μm after curing. The amount of warpage of the wafer was measured using the residual stress measurement device, and the residual stress generated between the silicon wafer and the polyimide film was evaluated. The smaller the value of the residual stress, the more excellent it is.
(6) Tensile elastic modulus, tensile strength Tensile elastic modulus and tensile strength were measured in accordance with JIS K7127 using a tensile tester "Strograph VG-1E" manufactured by Toyo Seiki Co., Ltd. The distance between the chucks is 50mm, the test piece size is 10mm × 50mm, and the test speed is 20mm / min. The larger the modulus of tensile elasticity and tensile strength, the better the coefficient values are.
(7) Light transmittance at a wavelength of 308 nm The light transmittance at a wavelength of 308 nm was measured using an ultraviolet-visible near-infrared spectrophotometer "UV-3100PC" manufactured by Shimadzu Corporation. The smaller the numerical value of the light transmittance at a wavelength of 308 nm, the better the laser peelability.

The tetracarboxylic acid components and diamine components used in the examples and comparative examples, and their abbreviations are as follows.
> Tetracarboxylic acid component>
CpODA: norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6,6 ''-tetracarboxylic dianhydride (JX Energy ( Shares) company system; compounds represented by formula (a-1))
BPDA: 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride (manufactured by Mitsubishi Chemical Corporation); compound represented by formula (a-2)
X-22-168AS: acid anhydride modified polysiloxane "X-22-168AS" (made by Shin-Etsu Chemical Industry Co., Ltd .; compound represented by formula (a-3))
>Diamine>
TFMB: 2,2'-bis (trifluoromethyl) benzidine (manufactured by Wakayama Seiki Chemical Industry Co., Ltd .; compound represented by formula (b-1))
3,5-DABA: 3,5-diaminobenzoic acid (manufactured by Japan Pure Pharmaceutical Co., Ltd .; compound represented by formula (b-2))

> Example 1>
25.619 g (0.080 mol) of TFMB was placed in a 1-liter five-necked round bottom flask equipped with a stainless steel half-moon stirring blade, a nitrogen introduction tube, a Dean-Stark device equipped with a cooling tube, a thermometer, and a glass end cap. , 3.043 g (0.020 mol) of 3,5-DABA, and 80.520 g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Corporation) at a temperature of 70 ° C in a nitrogen atmosphere at a rotation speed of 150 rpm Stir to obtain a solution.
To this solution were added 38.438 g (0.100 mole) of CpODA and 20.130 g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Co., Ltd.) at one time, and 0.911 g of the trimethylimidization catalyst was added Ethylamine (manufactured by Kanto Chemical Co., Ltd.) was heated with a heating jacket, and the temperature inside the reaction system was raised to 190 ° C over about 20 minutes. While collecting the distilled components and adjusting the rotation speed in accordance with the viscosity increase, the temperature in the reaction system was maintained at 190 ° C and refluxed for 3 hours.
Then, 470.816 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added, and the internal temperature of the reaction system was cooled to 120 ° C., and further stirred for about 3 hours to make it uniform, and a polymer having a solid content concentration of 10.0 mass%醯 imine varnish.
Next, the obtained polyimide varnish was coated on a glass plate and a silicon wafer, and held at 80 ° C. for 30 minutes by a hot plate, and then heated at 400 ° C. for 30 minutes in a hot air dryer under a nitrogen atmosphere. Then, the solvent was evaporated to obtain a thin film having a thickness of 7 m. The results are shown in Table 1.

> Example 2>
Change the amount of TFMB from 25.619g (0.080 moles) to 16.012g (0.050 moles) and the amount of 3,5-DABA from 3.043g (0.020 moles) to 7.608g (0.050 moles), otherwise A polyimide varnish was produced in the same manner as in Example 1 except that a polyimide varnish having a solid content concentration of 10.0% by mass was obtained.
Using the obtained polyimide varnish, a film was produced in the same manner as in Example 1 to obtain a film having a thickness of 9 μm. The results are shown in Table 1.

> Comparative example 1>
The amount of TFMB was changed from 25.619 g (0.080 mol) to 32.024 g (0.100 mol), except that 3,5-DABA was not added. A polyimide varnish was produced in the same manner as in Example 1. A polyimide varnish having a solid content concentration of 10.0% by mass was obtained.
Using the obtained polyimide varnish, a film was produced in the same manner as in Example 1 to obtain a film having a thickness of 14 μm. The results are shown in Table 1.

> Comparative example 2>
A 1-liter, five-necked round-bottom flask equipped with a stainless steel half-moon stirring blade, a nitrogen introduction tube, a Dean-Stark device equipped with a cooling tube, a thermometer, and a glass end cap was charged with 32.024 g (0.100 mol) of TFMB And 196.627 g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Corporation) were stirred at a temperature of 50 ° C. in a nitrogen atmosphere at a rotation speed of 150 rpm to obtain a solution.
To this solution, 294.22 g (0.100 mole) of BPDA and 49.157 g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Corporation) were put into the solution at one time, and the temperature was kept at 50 ° C. with a heating mantle and stirred for 7 hours.
Then, 307.230 g of N-methylpyrrolidone (manufactured by Mitsubishi Chemical Corporation) was added, and the mixture was further stirred for about 3 hours to make it uniform, thereby obtaining a polyamic acid varnish having a solid content concentration of 10.0% by mass.
Next, the obtained polyamic acid varnish was coated on a glass plate and a silicon wafer, and held at 80 ° C. for 20 minutes by a hot plate, and then heated at 400 ° C. for 30 minutes in a hot air dryer under a nitrogen atmosphere. In order to evaporate the solvent and thermally imidize it, a thin film having a thickness of 12 μm was obtained. The results are shown in Table 1.

[Table 1]

As shown in Table 1, the polyimide films of Examples 1 and 2 were excellent in heat resistance and colorless transparency, and had low residual stress.
On the other hand, the polyimide film of Comparative Example 1 is different from the polyimide film of Examples 1 and 2 in that it uses only TFMB as the diamine component, compared to the polyimide films of Examples 1 and 2. Rhenimine film has poor heat resistance.
The polyimide film of Comparative Example 2 produced using only TFMB as the diamine component and BPDA as the tetracarboxylic acid component was inferior in heat resistance, colorless transparency, and high residual stress.

> Example 3>
Except changing the amount of CpODA from 38.438 g (0.100 mol) to 30.750 g (0.080 mol) and adding 5.884 g (0.020 mol) of BPDA, Polyurethane was produced in the same manner as in Example 1. Amine varnish to obtain a polyimide varnish having a solid content concentration of 10.0% by mass.
Using the obtained polyimide varnish, a film was produced in the same manner as in Example 1 to obtain a film having a thickness of 10 μm. The results are shown in Table 2.

> Examples 4 to 7>
A polyimide varnish was produced in the same manner as in Example 3 except that the amounts of CpODA, BPDA, TFMB, and 3,5-DABA were changed to achieve the Mohr ratios described in Table 2, and a solid content concentration of 10.0 mass was obtained. % Polyimide varnish. Using the obtained polyimide varnish, a film was produced in the same manner as in Example 3. The evaluation results of the obtained film are shown in Table 2.

[Table 2]

> Example 8>
Change the amount of CpODA from 38.438 g (0.100 mol) to 29.716 g (0.07731 mol), and add 5.687 g (0.01933 mol) of BPDA, 3.373 g (0.00336 mol) of X-22-168AS, and so on A polyimide varnish was produced in the same manner as in Example 1 except that a polyimide varnish having a solid content concentration of 10.0% by mass was obtained.
Using the obtained polyimide varnish, a film was produced in the same manner as in Example 1 to obtain a film having a thickness of 15 μm. The results are shown in Table 3.

> Examples 9 to 13>
Except changing the amounts of CpODA, BPDA, X-22-168AS, TFMB, and 3,5-DABA to achieve the molar ratios described in Table 3, a polyimide varnish was produced in the same manner as in Example 8, A polyimide varnish having a solid content concentration of 10.0% by mass was obtained. Using the obtained polyimide varnish, a film was produced in the same manner as in Example 8. The evaluation results of the obtained film are shown in Table 3.

[table 3]

As shown in Tables 2 and 3, the polyimide films of Examples 3 to 13 were excellent in heat resistance and colorless transparency, and had low residual stress. In addition, the light transmittance at a wavelength of 308 nm is small, that is, the laser peelability is also excellent.

Claims (12)

A polyfluorene imide resin having a constitutional unit A derived from a tetracarboxylic dianhydride and a constitutional unit B derived from a diamine, and the constitutional unit A includes a constitutional unit (A-1) derived from a compound represented by the following formula (a-1) ), The constituent unit B includes a constituent unit (B-1) derived from a compound represented by the following formula (b-1), and a constituent unit (B-2) derived from a compound represented by the following formula (b-2); In the formula (b-2), X is a single bond, a substituted or unsubstituted alkylene group, a carbonyl group, an ether group, a group represented by the following formula (b-2-i), or the following formula (b-2- ii) the base represented, p is an integer from 0 to 2, m1 is an integer from 0 to 4, and m2 is an integer from 0 to 4; however, when p is 0, m1 is an integer from 1 to 4; In formula (b-2-i), m3 is an integer of 0 to 5. In formula (b-2-ii), m4 is an integer of 0 to 5. In addition, m1 + m2 + m3 + m4 is 1 or more, p When it is 2, two X and two m2 to m4 are selected independently. For example, the polyimide resin according to item 1 of the patent application scope, wherein the constituent unit (B-2) is a constituent unit (B-21) derived from a compound represented by the following formula (b-21); . For example, the polyimide resin according to item 1 or 2 of the patent application scope, wherein the ratio of the constituent unit (A-1) in the constituent unit A is 40 mol% or more. For example, a polyimide resin according to any one of claims 1 to 3, wherein, The ratio of the constituent unit (B-1) in the constituent unit B is 35 to 95 mol%, The ratio of the constituent unit (B-2) in the constituent unit B is 5 to 65 mol%. For example, the polyimide resin according to any one of claims 1 to 4, in which the ratio of the constitutional unit (B-1) to the constitutional unit (B-2) in the constitutional unit B [( B-1) / (B-2)] (mol / mol) is 35/65 to 95/5. For example, the polyimide resin according to any one of claims 1 to 5, wherein the constitutional unit A further comprises a constitutional unit (A-2) derived from a compound represented by the following formula (a-2); . For example, the polyimide resin according to item 6 of the patent application, wherein, in the constitutional unit A, the ratio of the constitutional unit (A-1) to the constitutional unit (A-2) [(A-1) / ( A-2)] (mol / mol) is 40/60 to 95/5. For example, the polyimide resin according to any one of claims 1 to 7, wherein the constitutional unit A further comprises constitutional units (A-3) derived from both end-anhydride-modified polysiloxanes. For example, the polyimide resin according to item 8 of the patent application scope, wherein, in the constituent unit A, the ratio of the constituent unit (A-1) to the constituent unit (A-3) [(A-1) / ( A-3)] (mol / mol) is 50/50 to 99/1. A method for producing a polyimide resin is represented by a tetracarboxylic acid component containing a compound represented by the following formula (a-1), a compound containing the compound represented by the following formula (b-1), and the following formula (b-2) The diamine component of the compound is heated in the presence of a reaction solvent to carry out amidation reaction; In the formula (b-2), X is a single bond, a substituted or unsubstituted alkylene group, a carbonyl group, an ether group, a group represented by the following formula (b-2-i), or the following formula (b-2- ii) the base represented, p is an integer from 0 to 2, m1 is an integer from 0 to 4, and m2 is an integer from 0 to 4; however, when p is 0, m1 is an integer from 1 to 4; In formula (b-2-i), m3 is an integer of 0 to 5. In formula (b-2-ii), m4 is an integer of 0 to 5. In addition, m1 + m2 + m3 + m4 is 1 or more, p When it is 2, two X and two m2 to m4 are selected independently. A polyimide varnish is prepared by dissolving a polyimide resin as described in any one of claims 1 to 9 in an organic solvent. A polyimide film containing the polyimide resin according to any one of claims 1 to 9 of the scope of patent application.