WO2013146460A1

WO2013146460A1 - High-transparency polyimide resin

Info

Publication number: WO2013146460A1
Application number: PCT/JP2013/057793
Authority: WO
Inventors: 明伸竹上; 礼子峯; 祥二廣; 川原　康行
Original assignee: 新日本理化株式会社
Priority date: 2012-03-30
Filing date: 2013-03-19
Publication date: 2013-10-03
Also published as: TW201400527A

Abstract

The present invention provides a polyimide resin having high transparency, excellent heat resistance, and a low coefficient of linear thermal expansion, and pertains more specifically to a polyimide resin obtained by running an imidization polymerization reaction of bicyclo[4.2.0]octane-3,4,7,8-tetracarboxylic dianhydride, an aromatic diamine compound, and, as needed, an alicyclic diamine compound, the total of the diamine compounds being in the range of 90-110 in terms of molar ratio in relation to 100 of the tetracarboxylic dianhydride.

Description

Highly transparent polyimide resin

The present invention relates to a highly transparent polyimide resin.

Conventionally, polyimide resins have been widely used as resins for electronic materials because they are excellent in heat resistance, strength, electrical insulation and the like. However, since a general polyimide resin is strongly colored, its use is limited.

Therefore, research on improving the hue of polyimide resin has been conducted, and a method of using a fluorine compound as a polyimide resin raw material has been discovered (Non-Patent Document 1). However, polyimide resin raw materials having fluorine atoms are uneconomical because they are difficult to produce and are expensive.

As another method for improving the hue of polyimide resin, studies have been conducted on using aliphatic or alicyclic compounds as polyimide resin raw materials. In particular, it has been found that the use of alicyclic acid dianhydride has a great effect on hue improvement (Non-patent Document 2).

Also, transparent polyimide is expected especially for glass replacement applications. In the current flat panel display field, a technique using a glass substrate is the mainstream. Glass is a material excellent in properties such as high transparency, high heat resistance, and low linear expansion coefficient, but has a problem that it is easily broken when subjected to an impact and has a large specific gravity. Therefore, development of the polyimide resin excellent in the flexibility which satisfy | fills high transparency, high heat resistance, and a low linear expansion coefficient was calculated | required.

An object of the present invention is to provide a polyimide resin excellent in high transparency, heat resistance and low linear expansion coefficient.

As a result of intensive studies to solve the above problems, the present inventors have used a specific tetracarboxylic dianhydride and a specific diamine compound as raw materials, so that high transparency, heat resistance and low line are achieved. As a result of finding out that a polyimide resin having an excellent expansion coefficient can be obtained and further studying it, the present invention has been completed.

That is, the present invention relates to the following polyimide resin.
Item 1. General formula (1)

A tetracarboxylic dianhydride represented by:
An aromatic diamine compound,
A polyimide resin obtained by imidation polymerization reaction in a molar ratio of the total of the diamine compounds with respect to the tetracarboxylic dianhydride 100 in the range of 90 to 110.
Item 2. The aromatic diamine compound is represented by the general formula (2)

Item 2. The polyimide resin according to Item 1, which is at least one kind represented by the diamine compound.
Item 3. Aromatic diamine compounds
(A) bis [4- (4-aminophenoxy) phenyl] sulfone, and (B) general formula (3)

Item 2. The polyimide resin according to Item 1, which is at least one kind represented by the diamine compound.
Item 4. General formula (1)

A tetracarboxylic dianhydride represented by:
An aromatic diamine compound and an alicyclic diamine compound,
A polyimide resin obtained by imidation polymerization reaction in a molar ratio of the total of the diamine compounds with respect to the tetracarboxylic dianhydride 100 in the range of 90 to 110.
Item 5. The alicyclic diamine compound has the general formula (4)

Item 5. The polyimide resin according to Item 4, which is at least one kind represented by the diamine compound.
Item 6. The aromatic diamine compound is represented by the general formula (2)

Item 6. The polyimide resin according to Item 4 or 5, which is at least one kind represented by the diamine compound.
Item 7. The aromatic diamine compound is represented by the general formula (5)

Item 6. The polyimide resin according to Item 4 or 5, which is at least one kind represented by the diamine compound.
Item 8. The aromatic diamine compound is represented by the general formula (6)

Item 6. The polyimide resin according to Item 4 or 5, which is at least one kind represented by the diamine compound.
Item 9. General formula (1)

A tetracarboxylic dianhydride represented by:
An aromatic diamine compound,
A polyamic acid resin obtained by copolymerization reaction with respect to the tetracarboxylic dianhydride 100 in a molar ratio of 90 to 110 in total.
Item 10. The aromatic diamine compound is represented by the general formula (2)

Item 10. The polyamic acid resin according to Item 9, which is at least one kind represented by the diamine compound.
Item 11. The aromatic diamine compound is represented by the general formula (5)

Item 11. The polyamic acid resin according to Item 10, which is at least one kind represented by the diamine compound:
Item 12. General formula (1)

A tetracarboxylic dianhydride represented by:
An aromatic diamine compound and an alicyclic diamine compound,
A polyamic acid resin obtained by imidization polymerization reaction with respect to the tetracarboxylic dianhydride 100 in a molar ratio of 90 to 110 in total.
Item 13. The alicyclic diamine compound has the general formula (4)

Item 13. The polyamic acid resin according to Item 12, which is at least one kind represented by the diamine compound.
Item 14. The aromatic diamine compound is represented by the general formula (2)

Item 14. The polyamic acid resin according to Item 12 or 13, which is at least one kind represented by the diamine compound.
Item 15. Item 9. A polyimide varnish containing the polyimide resin according to any one of Items 3 to 8 and an organic solvent.
Item 16. Item 15. A polyamic acid varnish containing the polyamic acid resin according to any one of Items 9 to 14 and an organic solvent.
Item 17. Item 16. A polyimide molded body obtained by molding the polyimide varnish according to Item 15.
Item 18. Item 18. A polyimide molded body obtained by molding the polyamic acid varnish according to Item 16.
Item 19. Item 19. The polyimide molded body according to item 17 or 18, wherein the polyimide molded body is in the form of a film, a film, or a sheet.
Item 20. Item 20. A plastic substrate comprising the polyimide molded article according to any one of Items 17 to 19.
Item 21. Item 20. An electrical component or electronic component comprising the plastic substrate according to Item 20.

According to the present invention, a polyimide resin excellent in high transparency, heat resistance and low linear expansion coefficient can be obtained. A plastic substrate made of a molded body of the polyimide resin can be used for electrical parts, electronic parts and the like.

In addition, the polyimide resin can be used for heat-resistant insulating materials, heat-resistant paints, heat-resistant coating materials, heat-resistant adhesives, and the like.

Hereinafter, the present invention will be described in detail.
I. Polyimide resin The polyimide resin of the present invention has the following general formula (1):

It is obtained by imidation polymerization reaction of a tetracarboxylic dianhydride represented by the following and an aromatic diamine compound.

Or the following general formula (1)

It is obtained by carrying out imidation polymerization reaction of a tetracarboxylic dianhydride represented by the following formula, an aromatic diamine compound, and an alicyclic diamine compound.

I-1. Tetracarboxylic acid dianhydride represented by general formula (1) The tetracarboxylic dianhydride represented by the above general formula (1), which is a component of the polyimide resin of the present invention, is bicyclo [4.2. 0] Octane-3,4,7,8-tetracarboxylic dianhydride.

As a method for producing the tetracarboxylic dianhydride represented by the general formula (1), a photodimerization reaction is recommended. Specific examples include equimolar amounts of 1,2,3,6-tetrahydrophthalic anhydride and maleic anhydride in a ketone solvent such as methyl ethyl ketone, an ester solvent such as ethyl acetate, or an ether solvent such as dioxane. The tetracarboxylic dianhydride reactant can be obtained by dissolving and irradiating light of 250 to 400 nm using a high pressure mercury lamp or the like.

The tetracarboxylic dianhydride represented by the general formula (1) is a tetracarboxylic acid or a mono-, di-, tri- or tetra-acid chloride of tetracarboxylic acid and a mono-alcohol with a lower alcohol having 1 to 4 carbon atoms. It can also be used as a derivative such as di-, tri- or tetraester.

In the present invention, a part of the tetracarboxylic dianhydride represented by the general formula (1) can be replaced with another tetracarboxylic dianhydride as long as the effect is not hindered. Other tetracarboxylic dianhydrides include aromatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, and aliphatic tetracarboxylic dianhydrides.

Specific examples of the aromatic tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, and 4,4′-oxydiphthalic acid. Dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3,3 ′, 4,4′-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4 Dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride, 2,2-bis (3,4-dicarboxyphenoxyphenyl) propane dianhydride, 1, 1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,2-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) Eta Dianhydride, 1,2-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) methane Anhydride, 4,4 '-(p-phenylenedioxy) diphthalic dianhydride, 4,4'-(m-phenylenedioxy) diphthalic dianhydride, 2,3,6,7-naphthalenetetracarboxylic Acid dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 1,2-ethylenebis (anhydrotrimellitate), 1,3,3a, 4,5,9b-hexahydro-5 Examples thereof include (tetrahydro-2,5-dioxo-3-furanyl) naphtho [1,2-c] furan-1.3-dione and derivatives thereof.

Specific examples of the alicyclic tetracarboxylic dianhydride include 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,3-dimethyl-1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic dianhydride, 2,3,5-tricarboxycyclopentylacetic acid dianhydride, 3,5,6-tricarboxynorbonane-2-acetic acid dianhydride, 2,3,4,5-tetrahydrofurantetracarboxylic dianhydride, 5- (2,5-dioxotetrahydrofural) -3-methyl -3-Cyclohexene-1,2-dicarboxylic dianhydride, bicyclo [2.2.2] -oct-7-ene-2,3,5,6-tetracarboxylic dianhydride and their derivatives, etc. It is exemplified.

Specific examples of the aliphatic tetracarboxylic dianhydride include 1,2,3,4-butanetetracarboxylic dianhydride, 1,2,3,4-pentanetetracarboxylic dianhydride, and those And the like.

These other tetracarboxylic dianhydrides can be used alone or in combination of two or more for the imidation polymerization reaction.

When a part of the tetracarboxylic dianhydride represented by the general formula (1) is used in place of the other tetracarboxylic dianhydride, the amount used is the total tetracarboxylic dianhydride. The amount is preferably 20 mol% or less, more preferably 10 mol% or less, particularly 5 mol% or less, based on the number of moles of the product.

I-2. Aromatic diamine compound There is no restriction | limiting in particular as an aromatic diamine compound which is a structural component of the polyimide resin of this invention, The thing obtained by a commercial item or a conventionally well-known manufacturing method can be used.

Specific examples of the aromatic diamine compound include m-phenylenediamine, p-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylpropane, 4,4′-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl Sulfide, 3,4′-diaminodiphenyl sulfide, 3,3′-diaminodiphenyl sulfide, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4- Bis (3-aminophenoxy) benzene, 1,3 Bis (3-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- ( 3-aminophenoxy) phenyl] propane, 4,4′-bis (4-aminophenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether Bis [4- (3-aminophenoxy) phenyl] ether, 9,9-bis (4-aminophenyl) fluorene, 9,9-bis (4-amino-3-chlorophenyl) fluorene, 9,9-bis ( 4-amino-3-fluorophenyl) fluorene, O-tolidine, m-tolidine, 4,4'-diaminobenzanilide, 2,2'-bis ( Trifluoromethyl) -4,4'-diaminobiphenyl, 4-aminophenyl-4-amino benzoate, 2- (4-aminophenyl) -6-amino-benzoxazole and the like. Among these, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylpropane, 4,4′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 3,3′-diaminodiphenyl ether, 4,4′- Diaminodiphenyl sulfone, 3,3′-diaminodiphenyl sulfone, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (3-aminophenoxy) Benzene, 1,3-bis (3-aminophenoxy) benzene, bis [4- (4-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2 -Bis [4- (3-aminophenoxy) phenyl] propane, 4,4′-bis (4-amino Examples include phenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, bis [4- (4-aminophenoxy) phenyl] ether, bis [4- (3-aminophenoxy) phenyl] ether, and the like. . These aromatic diamine compounds may be used alone or in combination of two or more.

Preferred aromatic diamine compounds include aromatic diamine compounds represented by the following general formula (2).

More preferable aromatic diamine compounds include aromatic diamine compounds represented by the following general formula (5).

More preferable aromatic diamine compounds include aromatic diamine compounds represented by the following general formula (6).

Furthermore, as the aromatic diamine compound, (A) bis [4- (4-aminophenoxy) phenyl] sulfone, and (B) at least one selected from diamine compounds represented by the following general formula (3): It is preferable to use together.

More preferably, (A) bis [4- (4-aminophenoxy) phenyl] sulfone and (B) at least one selected from diamine compounds represented by the following general formula (7) may be used in combination. preferable.

I-3. Alicyclic diamine compound There is no restriction | limiting in particular as an alicyclic diamine compound which can be used as a structural component of the polyimide resin of this invention, The thing obtained by a commercial item or a conventionally well-known manufacturing method can be used.

Specific examples of the alicyclic diamine compound include diaminocyclohexane, diaminodicyclohexylmethane, dimethyl-diaminodicyclohexylmethane, tetramethyl-diaminodicyclohexylmethane, diaminodicyclohexylpropane, diaminobicyclo [2.2.1] heptane, bis ( Aminomethyl) -bicyclo [2.2.1] heptane, 3 (4), 8 (9) -bis (aminomethyl) tricyclo [5.2.1.0 ^2,6 ] decane, 1,3-bisamino Examples include methylcyclohexane and isophoronediamine. These alicyclic diamine compounds can be used alone or in combination of two or more kinds for the imidation polymerization reaction.

Preferred examples of the alicyclic diamine compound include diamine compounds represented by the following general formula (4).

When the alicyclic diamine compound is used in combination with an aromatic diamine compound, the molar ratio of the alicyclic diamine compound to the aromatic diamine compound is in the range of 80-20: 20-80, preferably 75-30: 25-70. In particular, it is preferably 70 to 40:30 to 60.

When the alicyclic diamine compound is used in combination with an aromatic diamine compound, a preferable aromatic diamine compound includes an aromatic diamine compound represented by the following general formula (2).

In addition, the alicyclic diamine compound and / or the aromatic diamine compound can be used by replacing a part thereof with the aliphatic diamine compound as long as the effects of the present invention are not hindered.

Specific examples of the aliphatic diamine compound include ethylene diamine, hexamethylene diamine, octamethylene diamine, decamethylene diamine and the like.

The above aliphatic diamine compounds can be used alone or in combination of two or more for the imidation polymerization reaction.

When a part of the alicyclic diamine compound and / or aromatic diamine compound is used in place of the above aliphatic diamine compound, the amount used is preferably 20 mol% with respect to the number of moles of the total diamine compound. In the following, 10 mol% or less, more preferably 5 mol% or less is recommended.

The molar ratio in the imidation polymerization reaction according to the present invention is preferably in the range of all diamine compounds 90 to 110 with respect to all tetracarboxylic dianhydrides 100. More preferably, it is in the range of 95 to 105, and still more preferably in the range of 98 to 102. By performing the imidization polymerization reaction within this range, a polyimide resin having a sufficient degree of polymerization can be obtained. In addition, as described above, the tetracarboxylic dianhydride, the alicyclic diamine compound, and the aromatic diamine compound can each be partially substituted with an aliphatic diamine compound within the range where the effects of the present invention are achieved. In that case, a similar molar ratio applies.

In the present specification and claims, the diamine compound is described in the form of “diamine”. However, as long as the effect of the present invention is obtained for the purpose of improving the reactivity, an amino group is substituted for them. A compound obtained by converting part or all into an isocyanate group, a silylated compound, or the like can be used.

II. Polyamic acid resin The polyamic acid resin which is a precursor of the polyimide resin according to the present invention is a copolymer of the tetracarboxylic dianhydride and the diamine compound described above in a reaction solvent in a temperature range of 5 ° C to 100 ° C. Obtained by reaction.

II-1. Copolymerization Reaction The reaction solvent used in the above copolymerization reaction may be any reaction solvent as long as it can dissolve the polyamic acid resin produced from the copolymerization reaction. For example, preferred examples include aprotic solvents, phenol solvents, ether solvents, carbonate solvents and the like.

Specific examples of aprotic solvents include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N-methylcaprolactam, 1,3-dimethylimidazolidinone, tetramethylurea, etc. Amide solvents, lactone solvents such as γ-butyrolactone and γ-valerolactone, phosphorus-containing amide solvents such as hexamethylphosphoric amide and hexamethylphosphine triamide, sulfur-containing dimethylsulfone, dimethylsulfoxide, sulfolane and the like Examples thereof include ketone solvents such as acetone, cyclohexane and methylcyclohexanone, amine solvents such as picoline and pyridine, and ester solvents such as acetic acid (2-methoxy-1-methylethyl).

Specific examples of the phenol solvent include phenol, o-cresol, m-cresol, p-cresol, 2,3-xylenol, 2,4-xylenol, 2,5-xylenol, 2,6-xylenol, 3,4 -Xylenol, 3,5-xylenol and the like are exemplified.

Specific examples of the ether solvent include ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, tetrahydrofuran, 1,4-dioxane and the like.

Specific examples of carbonate solvents include diethyl carbonate, methyl ethyl carbonate, ethylene carbonate, propylene carbonate, and the like.

The above reaction solvents may be used alone or in combination of two or more.

Among these reaction solvents, N-methyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, N, N-dimethylformamide, N, N-dimethylacetamide, and γ-butyrolactone are particularly recommended.

The amount of the reaction solvent used may be an amount that can dissolve the polyamic acid resin to be produced. The specific concentration of the polyamic acid resin is preferably adjusted to 5 to 50% by weight, more preferably 10 to 40% by weight, and still more preferably 10 to 30% by weight.

The interior of the copolymerization reaction system is preferably an inert gas atmosphere from the viewpoint of preventing coloration and safety of the reaction system. Usually, a method of replacing the inside of the reaction system with an inert gas and allowing the inert gas to flow during the reaction is recommended. Nitrogen, argon, etc. are illustrated as an inert gas.

In the copolymerization reaction of the polyamic acid resin according to the present invention, a salt generation inhibitor can be used. The salt generation inhibitor is preferably one that can be volatilized and removed when the polyamic acid resin varnish is heated to imidize.

As the salt generation inhibitor, for example, a general silylating agent can be used. Specific examples include N, O-bis (trimethylsilyl) acetamide, N, O-bis (trimethylsilyl) trifluoroacetamide, trimethylsilyl chloride, hexamethyldisilazane and the like.

The reaction time for the copolymerization reaction of the polyamide acid resin is usually preferably about 2 to 24 hours, although it depends on the charging ratio, the substrate concentration and the like. When reaction time is too short, the tendency for a polymerization degree to become low is recognized. If the reaction time is too long, the amide group part may partially undergo a hydrolysis reaction and the degree of polymerization may decrease.

The number average molecular weight of the obtained polyamic acid resin is preferably 6,000 or more, and the weight average molecular weight is 10,000 or more, more preferably the number average molecular weight is 6,000 to 100,000, and the weight The average molecular weight is in the range of 10,000 to 500,000. This range is a range having a degree of polymerization that can give a molded product. In the present specification and claims, the molecular weight of the polyamic acid resin is a value measured by the method described in the example of the later operation.

II-2. Imidation polymerization reaction As a method of imidation polymerization reaction, (1) tetracarboxylic dianhydride and diamine compound are heated in the presence of a reaction solvent and a small amount of azeotropic solvent, and the generated water is azeotropically removed from the system. (2) Chemical imidization method using dehydration action of acid anhydrides such as acetic anhydride and propionic anhydride, or carbodiimide compounds such as dicyclohexylcarbodiimide after producing polyamic acid as a polyimide precursor (3) A thermal imidization method in which the polyamic acid of the polyimide precursor is produced and then heated to 300 ° C. or higher is exemplified.

II-2-1. As a diamine compound, when a cycloaliphatic diamine compound is not used in combination , as a diamine compound, when a cycloaliphatic diamine compound is not used in combination, the thermal imidization method (3) is industrially preferable among the above polyimide resin production methods, For example, a method in which the polyamic acid resin is heated in a temperature range of 300 to 350 ° C. to distill off the generated water accompanying the imidization reaction and perform an imidation polymerization reaction.

It is recommended that the imidation ratio in the heat imidization reaction of the polyamic acid resin (3) is usually 70% or more, preferably 80% or more, more preferably 90% or more, and particularly 95% or more. Furthermore, it may be desirable to make the imidization rate close to 100% depending on the use application of the polyimide resin.

II-2-2. When using an alicyclic diamine compound as a diamine compound, when using an alicyclic diamine compound as a diamine compound, the thermal imidation method of (1) is industrially preferable among the methods for producing the polyimide resin, For example, the total amount of tetracarboxylic dianhydride and diamine compound is dissolved in the reaction solvent, or a part of tetracarboxylic dianhydride and / or diamine compound is dissolved stepwise, preferably 100 to 250 ° C., More preferred is a method of heating to 150 to 200 ° C. and distilling off generated water in the system with an azeotropic solvent to carry out an imidation polymerization reaction.

Moreover, the polymer terminal of a polyimide resin can be made into an amine terminal by using a diamine compound excessively with respect to tetracarboxylic dianhydride, On the other hand, using tetracarboxylic dianhydride more excessively than a diamine compound. Thus, the polymer terminal of the polyimide resin can be made an acid terminal.

Examples of the azeotropic solvent for distilling the generated water out of the system include aromatic hydrocarbons such as toluene, xylene and solvent naphtha, and alicyclic hydrocarbons such as cyclohexane, methylcyclohexane and dimethylcyclohexane. These can be used alone or as a mixed system. The amount used is usually about 1 to 30% by weight, preferably about 5 to 10% by weight, based on the amount of the reaction solvent.

The reaction system is preferably in an inert gas atmosphere from the viewpoint of preventing coloration and safety of the reaction system. Usually, a method of replacing the inside of the reaction system with an inert gas and allowing the inert gas to flow during the reaction is recommended. Nitrogen, argon, etc. are illustrated as an inert gas.

In the imidation polymerization reaction according to the present invention, a known catalyst can be used. However, it is preferable to carry out the reaction in the absence of a catalyst from the viewpoints of complicated post-treatment, deterioration of the storage stability of the polyimide varnish due to the residual amount of the catalyst used, and coloring of the polyimide varnish.

When a catalyst is used, for example, as a base catalyst, pyridine, quinoline, isoquinoline, α-picoline, β-picoline, 2,4-lutidine, 2,6-lutidine, trimethylamine, triethylamine, tripropylamine, tri Organic base catalysts such as butylamine, imidazole, N, N-dimethylaniline, N, N-diethylaniline, inorganic bases represented by potassium hydroxide, sodium hydroxide, potassium carbonate, sodium carbonate, potassium bicarbonate, sodium bicarbonate Examples are catalysts.

Examples of the acid catalyst include crotonic acid, acrylic acid, trans-3-hexenoic acid, cinnamic acid, benzoic acid, methylbenzoic acid, oxybenzoic acid, terephthalic acid, benzenesulfonic acid, p-toluenesulfonic acid, naphthalenesulfonic acid, etc. Is exemplified.

The reaction time of the imidation polymerization reaction is preferably about 2 to 10 hours after the start of the distillation of the soot-forming water, although it depends on the charging ratio, the substrate concentration and the like. When reaction time is too short, the tendency for imidation ratio to become low is recognized. If the reaction time is too long, the reaction system may partially cause a thermal crosslinking reaction to thicken the reaction system or form a gel-like material, or the reaction system may be colored due to thermal degradation of the reaction solvent. .

The number average molecular weight of the polyimide resin of the present invention obtained by imidation polymerization reaction is preferably 6,000 or more and the weight average molecular weight is 10,000 or more, more preferably the number average molecular weight is 6,000 to 100. And a weight average molecular weight in the range of 10,000 to 500,000. This range is a range having a degree of polymerization that can give a molded product. In addition, in this specification and a claim, the molecular weight of a polyimide resin is the value measured by the method described in the Example of the postoperative.

The imidation ratio in the imidation polymerization reaction is usually 70% or more, preferably 80% or more, more preferably 90% or more, and particularly 95% or more. Furthermore, it may be desirable to make the imidization rate close to 100% depending on the use application of the polyimide resin.

In addition, as long as the effects of the present invention are not impaired, known monofunctional acid anhydrides, monoamines, and the like used in this field can be used in combination as end cap agents for the purpose of molecular weight control and the like. Specific examples of the end cap agent include phthalic anhydride, maleic anhydride, nadic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc. for acid anhydrides, and aniline, methylaniline, allylamine, etc. for monoamines. .

III. Polyamic acid varnish The polyamic acid varnish of the present invention is characterized by containing a polyamic acid resin and an organic solvent. The organic solvent may be the same as or different from the organic solvent used for the copolymerization reaction of the tetracarboxylic dianhydride and the diamine compound, but may be the same in consideration of the complexity of solvent replacement work and the like. preferable.

The viscosity of the polyamic acid varnish can be appropriately selected depending on the desired application, but the viscosity at 25 ° C. is preferably in the range of 0.1 to 500 Pa · s, more preferably in the range of 1 to 100 Pa · s. The

The concentration of the polyamic acid resin in the polyamic acid varnish is preferably 5 to 50% by weight, more preferably 10 to 40% by weight, and further preferably 10 to 30% by weight. The

Also, when a polyimide resin coating is obtained from the polyamic acid varnish, a part of the organic solvent can be replaced with a low boiling point solvent for the purpose of efficiently performing the drying step. Such low boiling point solvents include aromatic hydrocarbons such as toluene, xylene, solvent naphtha, alicyclic hydrocarbons such as cyclohexane, methylcyclohexane and dimethylcyclohexane, ethers such as propylene glycol monomethyl ether, acetone, methyl ethyl ketone, Ketones such as methyl isobutyl ketone are exemplified. When these low-boiling solvents are used, the amount used is preferably 1 to 30% by weight, more preferably 5 to 20% by weight, based on the total amount of organic solvent.

In addition, other components may be added to the polyamic acid varnish which is the polyimide resin precursor of the present invention as long as the effects of the present invention are not hindered. For example, polyester resin, polyimide resin (excluding the polyimide resin of the present invention), polyamideimide resin, polymer compound such as polyamide resin, smoothing agent, leveling agent, defoaming agent, flame retardant, antifoaming agent, antioxidant Etc. are exemplified.

IV. Polyimide varnish Among the polyimide resins of the present invention, the diamine component is selected from (A) bis [4- (4-aminophenoxy) phenyl] sulfone and (B) a diamine compound represented by the general formula (3). The polyimide resin obtained by using together with at least 1 type which is used together, and the polyimide resin obtained by using together an aromatic diamine component and an alicyclic diamine compound melt | dissolve in a solvent. Therefore, the polyimide resin can be a polyimide varnish. The polyimide varnish contains a polyimide resin and an organic solvent. The organic solvent may be the same as or different from the organic solvent used in the imidation polymerization reaction, but is preferably the same in consideration of the complexity of solvent replacement work and the like.

As a method for preparing a polyimide varnish, (i) a method of using a reaction solvent solution of a polyimide resin obtained by an imidization polymerization reaction as it is as a polyimide varnish, (ii) a reaction solvent solution of a polyimide resin obtained by an imidization polymerization reaction Examples are a method of obtaining a polyimide varnish by isolating a polyimide resin from the following and then dissolving the isolated polyimide resin in a desired organic solvent.

The viscosity of the polyimide varnish can be appropriately selected depending on the desired application, but the viscosity at 25 ° C. is preferably in the range of 0.1 to 500 Pa · s, more preferably in the range of 1 to 100 Pa · s. .

The concentration of the polyimide resin in the polyimide varnish is preferably 5 to 50% by weight, more preferably 10 to 40% by weight, and even more preferably 10 to 30% by weight.

The organic solvent is not particularly limited as long as it can dissolve the polyimide resin according to the present invention, and specific examples include those exemplified as the reaction solvent. These can be used alone or as a mixed system. Of these, N-methyl-2-pyrrolidone, 1,3-dimethylimidazolidinone, N, N-dimethylformamide, N, N-dimethylacetamide, and γ-butyrolactone are recommended.

Also, when a polyimide resin coating film is obtained from a polyimide varnish, an organic solvent having a low boiling point is used for the purpose of preventing coloring of the polyimide resin coating film in the drying process. Specific examples include N, N-dimethylformamide and N, N-dimethylacetamide.

Furthermore, when a polyimide resin coating film is obtained from a polyimide varnish, a part of the organic solvent can be replaced with a low boiling point solvent for the purpose of efficiently performing the drying step. Such low boiling point solvents include aromatic hydrocarbons such as toluene, xylene, solvent naphtha, alicyclic hydrocarbons such as cyclohexane, methylcyclohexane and dimethylcyclohexane, ethers such as propylene glycol monomethyl ether, acetone, methyl ethyl ketone, Ketones such as methyl isobutyl ketone are exemplified. When these low-boiling solvents are used, the amount used is preferably 1 to 30% by weight, more preferably 5 to 20% by weight, based on the total amount of organic solvent.

In addition, other components may be added to the polyimide varnish of the present invention as long as the effects of the present invention are not hindered. For example, polyester resin, polyimide resin (excluding the polyimide resin of the present invention), polyamideimide resin, polymer compound such as polyamide resin, smoothing agent, leveling agent, defoaming agent, flame retardant, antifoaming agent, antioxidant Etc. are exemplified.

The polyimide varnish thus obtained is excellent in storage stability and used for various purposes.

V. Polyimide molded body The polyimide molded body of the present invention can be obtained by molding a polyamic acid varnish. There is no restriction | limiting in particular as a method to shape | mold, A conventionally well-known method can be used.

For example, after applying the polyamic acid varnish to a substrate (after coating or forming into a film, film, or sheet), the polyamic acid varnish is dried to 200 ° C. or higher, preferably 300 ° C. or higher, and heated imide Examples thereof include a method of forming a film-like, film-like or sheet-like polyimide molded body by removing the solvent while forming.

The polyimide molded body of the present invention can also be obtained by molding a polyimide varnish. There is no restriction | limiting in particular as a method to shape | mold, A conventionally well-known method can be used.

For example, after the polyimide varnish is applied to a substrate (after being applied or formed into a film, film, or sheet), the organic solvent is removed from the polyimide varnish to form a film, film, or sheet polyimide. The method etc. which shape | mold to a molded object are illustrated.

As an example of producing a polyimide molded body, a polyamic acid varnish or a polyimide varnish is cast on a PET substrate (polyethylene terephthalate substrate), and then in a vacuum dryer (decompression degree 1 to 10 mmHg) at room temperature for 30 minutes to 2 hours. Further, the temperature is raised to about 200 ° C. over 30 minutes to 2 hours, and the solvent is distilled off at that temperature for 1 to 4 hours. After cooling to room temperature, the polyimide film formed on the PET substrate is taken out from the vacuum dryer and peeled off from the PET substrate. The peeled polyimide film is fixed to a stainless steel metal frame, heated again from room temperature to 230 to 330 ° C in 1 to 4 hours using a vacuum dryer, and dried at that temperature for 2 to 5 hours to completely remove the solvent. After distilling off and cooling to room temperature, a polyimide film can be obtained by taking out from the vacuum dryer. A method of adjusting the thickness of the polyimide film thus obtained to a target thickness by adjusting the coating thickness at the time of casting can be mentioned.

The high transparency of the polyimide resin of the present invention can be evaluated by the total light transmittance. The range of the total light transmittance is preferably 87% or more, more preferably 88% or more, and particularly preferably 89% or more. The total light transmittance is a value obtained by the method described in Examples described later in this specification and claims. For example, the above range of the total light transmittance is an effective range particularly in applications requiring high transparency.

The heat resistance of the polyimide resin of the present invention can be evaluated by the glass transition temperature. The range of the glass transition temperature is preferably 250 ° C. or higher, more preferably 260 ° C. or higher, and particularly preferably 270 ° C. or higher. The glass transition temperature is a value obtained by the method described in Examples described later in the present specification and claims. For example, the above glass transition temperature range is an effective range particularly for applications requiring heat resistance.

The range of the linear expansion coefficient of the polyimide resin of the present invention is preferably 65 ppm / K or less, more preferably 62 ppm / K or less, and particularly preferably 60 ppm / K or less. The linear expansion coefficient is a value obtained by the method described in Examples described later in the present specification and claims. For example, the range of the above-mentioned linear expansion coefficient is a range that is particularly effective for use with a transparent flexible substrate such as an organic EL.

VI. Plastic Substrate / Electric Component / Electronic Component The plastic substrate of the present invention is characterized by comprising the polyimide molded body. As the production method, a conventionally known production method can be used.

The plastic substrate is preferably used for, for example, a flexible transparent substrate because the polyimide molded body of the present invention has high transparency, heat resistance, and a low linear expansion coefficient.

In addition, the flexible transparent substrate is used in many electrical components or electronic components, and is suitably used as components such as electronic paper, organic solar cells, organic EL lighting, and flexible liquid crystal displays.

VII. Heat-resistant insulating material / heat-resistant coating material / heat-resistant coating material / heat-resistant adhesive material The heat-resistant insulating material, heat-resistant coating material, heat-resistant coating material or heat-resistant adhesive material of the present invention uses the polyimide resin of the present invention. As the production method, a conventionally known production method can be used. In any case, the polyimide resin is preferably used because it has high transparency, heat resistance and a low linear expansion coefficient.

Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples. In addition, the measuring method of each characteristic in an Example and a comparative example and the abbreviation of a compound are as follows.

<Abbreviation of compound>
Tetracarboxylic dianhydride BCODA: bicyclo [4.2.0] octane-3,4,7,8-tetracarboxylic dianhydride DSDA: 3,3 ′, 4,4′-diphenylsulfone tetracarboxylic acid Dianhydride

Aromatic diamine compound DPE: 4,4′-diaminodiphenyl ether DAM: 4,4′-diaminodiphenylmethane BAPP: 2,2-bis [4- (4-aminophenoxy) phenyl] propane BAPS: bis [4- (4 -Aminophenoxy) phenyl] sulfone BAPB: 4,4'-bis (4-aminophenoxy) biphenyl TPE-Q: 1,4-bis (4-aminophenoxy) benzene m-TD: m-tolidine

-Alicyclic diamine compound HDAM: 4,4'-methylenebis (cyclohexylamine)
DMHDAM: 3,3′-dimethyl-4,4′-methylenebis (cyclohexylamine)
NBDA: Norbornanediamine

Reaction solvent NMP: N-methyl-2-pyrrolidone DMAc: N, N′-dimethylacetamide ECH: Ethylcyclohexane

<Number average molecular weight and weight average molecular weight of polyimide resin and polyamic acid resin>
A sample solution for molecular weight measurement is prepared by diluting about 1 g of a polyimide resin reaction solution (polyimide varnish) or polyamic acid varnish with about 30 ml of N, N-dimethylformamide. The number average molecular weight (Mn) and weight average molecular weight (Mw) in terms of polystyrene were determined under the following measurement conditions using gel permeation chromatography (GPC).

[Measurement condition]
Equipment: EcoSEC HLC-8320GPC manufactured by Tosoh Corporation
Column: manufactured by Tosoh Corporation One SuperH-H and three SuperHM-Ms connected in series Column temperature: 40 ° C
Eluent: (5.15 mmol / L-lithium bromide + 5.10 mmol / L-phosphoric acid) / N, N-dimethylformamide Flow rate: 0.5 mL / min
Detector: RI

<Evaluation of solvent solubility>
Solvent solubility was evaluated by visually observing the state after adjusting the concentration of the polyimide resin to 15% by weight after completion of the imidation polymerization reaction and leaving it at room temperature for 24 hours. Even after being allowed to stand for 24 hours, no precipitate was generated and no gelation of the reaction solution was observed.

<Linear expansion coefficient>
In accordance with JIS K7197 (1991), the polyimide film (40 μm) was heated in a normal air dryer at 300 ° C. for 30 minutes for stress relaxation treatment. A 4.0 × 10.0 mm piece cut from this film was measured using a TMA / SS6100 manufactured by SII NanoTechnology Co., Ltd. under the conditions of a nitrogen flow rate of 200 ml / min and a heating rate of 10 ° C./min. The average value of the measured values was taken as the linear expansion coefficient.

<Total light transmittance>
In accordance with JIS K7361-1 (1997), a polyimide film (40 μm) was measured using a HAZE-GUARD II manufactured by Toyo Seiki Co., Ltd. by a single beam method using a D65 light source.

<Glass transition temperature>
Using a dynamic viscoelasticity measuring device RHEOGEL-E4000 (manufactured by UPM), tan δ of the polyimide molded body (film) was measured under the following measurement conditions. The maximum value of tan δ was defined as the glass transition temperature (° C.).

[Measurement condition]
Measurement mode: Tensile mode Sine wave: 10 Hz
Temperature increase rate: 5 ° C / min
Air flow rate: 10L / min

<Mechanical property evaluation>
The “elastic modulus”, “strength”, and “elongation” of the polyimide molded body (film) were measured according to JIS K-7161 (1994) using a universal material testing machine 5565 manufactured by Instron.

Production Example BCODA was produced with reference to US Pat. No. 3,342,431. Specifically, in a 1500 ml internal irradiation type Pyrex (registered trademark) glass five-necked reaction flask, 95.0 g (969 mmol) of maleic anhydride and 1,2,3,6-tetrahydrophthalic anhydride 192 were added. 0.0 g (1262 mmol) and 1200 g of n-butyl acetate were charged and stirred and dissolved at room temperature while covering the outer wall of the reactor with aluminum foil. Further, nitrogen gas was bubbled for 15 minutes to remove oxygen in the reaction vessel. Subsequently, the reaction vessel was cooled to 20 ° C. while stirring, and light irradiation was continued for 24 hours using a 400 W high-pressure mercury lamp in a light source cooling tube in the center of the flask. After completion of the reaction, the precipitated crystals were filtered, washed with 60 g of n-butyl acetate, and then dried to obtain 59.9 g (239 mmol, yield 25%) of BCODA crystals.

Example 1
To a 200 mL Erlenmeyer flask equipped with a stirrer, 136 g of NMP and 11.04 g (52 mol) of m-TD as an aromatic diamine compound were added and stirred for 15 minutes. BCODA 13.01 g (52 mmol) was added to the resulting solution and stirred overnight to obtain a polyamic acid varnish. Table 1 shows the measurement results of the average molecular weight of the polyamic acid resin.

Example 2
A polyamic acid varnish of the present invention was obtained in the same manner as in Example 1 except that the aromatic diamine compound was changed to 10.41 g (52 mmol) of DPE. Table 1 shows the measurement results of the average molecular weight of the polyamic acid resin.

Example 3
A polyamic acid varnish of the present invention was obtained in the same manner as in Example 1 except that the aromatic diamine compound was changed to 15.20 g (52 mmol) of TPE-Q. Table 1 shows the measurement results of the average molecular weight of the polyamic acid resin.

Example 4
A polyamic acid varnish of the present invention was obtained in the same manner as in Example 1 except that the aromatic diamine compound was changed to 19.16 g (52 mmol) of BAPB. Table 1 shows the measurement results of the average molecular weight of the polyamic acid resin.

Example 5
A polyamic acid varnish of the present invention was obtained in the same manner as in Example 1, except that the aromatic diamine compound was changed to 22.49 g (52 mmol) of BAPS. Table 1 shows the measurement results of the average molecular weight of the polyamic acid resin.

Example 6
A polyamic acid varnish of the present invention was obtained in the same manner as in Example 1 except that the aromatic diamine compound was changed to 10.31 g (52 mmol) of DAM. Table 1 shows the measurement results of the average molecular weight of the polyamic acid resin.

Comparative Example 1
A polyamic acid varnish was obtained in the same manner as in Example 2 except that the tetracarboxylic dianhydride was changed from BCODA to 18.63 g (52 mol) of DSDA. Table 1 shows the measurement results of the average molecular weight of the polyamic acid resin.

Experimental example 1
The polyamic acid varnishes obtained in Examples 1 to 6 were applied onto a glass substrate using a bar coater so that the dry film thickness was 40 μm, and was vacuumed in a vacuum dryer (decompression degree: 10 mmHg or less) at 300 ° C. * It dried for 1 hour, and after making it cool to room temperature, it was made to peel from a glass substrate, and the polyimide molded body (film) was obtained. Table 1 shows the measurement results of the linear expansion coefficient, total light transmittance, glass transition temperature, and mechanical properties of the obtained polyimide molded body (film).

Experimental example 2
The polyamic acid varnish obtained in Comparative Example 1 was applied onto a glass substrate using a bar coater so that the dry film thickness was 40 μm, and was vacuumed (with a reduced pressure of 10 mmHg or less) at 300 ° C. × 1 in a vacuum dryer. After drying for a time and cooling to room temperature, it was made to peel from a glass substrate, and the polyimide molded body (film) was obtained. Table 1 shows the measurement results of the linear expansion coefficient, total light transmittance, glass transition temperature, and mechanical properties of the obtained polyimide molded body (film).

Example 7
In a 200 mL four-necked flask equipped with a thermometer, a stirrer, a nitrogen introducing tube, a separator decanter, and a condenser tube, 13.01 g (52 mmol) of BCODEA, 5.21 g (26 mmol) of DPE and 11.24 g of BAPS as an aromatic diamine compound ( 26 mmol) DMAc (99 g) as a reaction solvent and ECH (11 g) as an azeotropic solvent, the inside of the reaction system was purged with nitrogen, and then stirred at 160 ° C. in a nitrogen stream to remove the generated water from the system for 5 hours. Went. After the reaction, DMAc was added so that the resin concentration was 20% by weight to obtain a DMAc solution of the polyimide resin of the present invention (polyimide varnish of the present invention). Table 2 shows the measurement results of the average molecular weight of the obtained polyimide resin.

Example 8
A DMAc solution of the polyimide resin of the present invention (polyimide varnish of the present invention) was prepared in the same manner as in Example 7, except that the aromatic diamine compound was changed to 3.12 g (15.6 mmol) of DPE and 15.74 g (36.4 mmol) of BAPS. ) Table 2 shows the measurement results of the average molecular weight of the obtained polyimide resin.

Example 9
Except that the aromatic diamine compound was changed to 4.42 g (20.8 mmol) of m-TD and 13.49 g (31.2 mmol) of BAPS, a DMAc solution of the polyimide resin of the present invention (of the present invention) was prepared in the same manner as in Example 7. Polyimide varnish) was obtained. Table 2 shows the measurement results of the average molecular weight of the obtained polyimide resin.

Example 10
In a 200 mL four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube, a separator decanter, and a condenser tube, 13.28 g (53.1 mmol) of BCODA and 5.55 g (26.4 mmol) of HDAM as an alicyclic diamine compound Then, DPE 5.29 g (26.4 mmol) as a reaction solvent, DMAc 123.9 g as a reaction solvent, ECH 13.7 g as an azeotropic solvent were charged, and the reaction system was purged with nitrogen, followed by stirring at 160 ° C. under a nitrogen stream. A dehydration imidation polymerization reaction was carried out for 5 hours while removing the produced water out of the system. After the reaction, DMAc was added so that the resin concentration was 15% by weight to obtain a DMAc solution of the polyimide resin of the present invention (polyimide varnish of the present invention). Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 11
A polyimide varnish of the present invention was obtained in the same manner as in Example 10 except that the aromatic diamine compound was changed to 5.23 g (26.4 mmol) of DAM. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 12
A polyimide varnish of the present invention was obtained in the same manner as in Example 10 except that the amount of BCODA charged was changed to 12.33 g (49.3 mmol). Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 13
A polyimide varnish of the present invention was obtained in the same manner as in Example 12, except that the alicyclic diamine compound was changed to 7.77 g (37.0 mmol) of HDAM and the aromatic diamine compound was changed to 3.17 g (15.8 mmol) of DPE. . Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 14
A polyimide varnish of the present invention was obtained in the same manner as in Example 12 except that the alicyclic diamine compound was changed to 6.29 g (26.4 mmol) of DMHDAM. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 15
A polyimide varnish of the present invention was obtained in the same manner as in Example 12 except that the alicyclic diamine compound was changed to 2.78 g (13.2 mmol) of HDAM and 2.04 g (13.2 mmol) of NBDA. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 16
A polyimide varnish of the present invention was obtained in the same manner as in Example 12 except that the aromatic diamine compound was changed to 5.23 g (26.4 mmol) of DAM. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 17
A polyimide varnish of the present invention was obtained in the same manner as in Example 12, except that the aromatic diamine compound was changed to 10.84 g (26.4 mmol) of BAPP. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 18
A polyimide varnish of the present invention was obtained in the same manner as in Example 12 except that the aromatic diamine compound was changed to 11.42 g (26.4 mmol) of BAPS. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 19
The polyimide of the present invention was prepared in the same manner as in Example 12, except that the aromatic diamine compound was changed to 9.73 g (26.4 mmol) of BAPB, the reaction solvent was changed to 123.9 g of NMP, and 13.7 g of xylene as the azeotropic solvent. A varnish was obtained. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 20
A polyimide varnish of the present invention was obtained in the same manner as in Example 19 except that the aromatic diamine compound was changed to 7.72 g (26.4 mmol) of TPE-Q. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Example 21
A polyimide varnish of the present invention was obtained in the same manner as in Example 19 except that the aromatic diamine compound was changed to 5.60 g (26.4 mmol) of m-TD. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Comparative Example 2
A polyimide varnish was obtained in the same manner as in Example 9, except that BCODA was changed to 19.02 g (53.1 mmol) of DSDA. Table 2 shows the measurement results of the average molecular weight and solvent solubility of the obtained polyimide resin.

Experimental example 3
The polyimide varnishes obtained in Examples 7 to 21 were applied onto a glass substrate using a bar coater so that the dry film thickness was 40 μm, and the vacuum was reduced in a vacuum dryer (decompression degree: 10 mmHg or less) at 300 ° C. After drying for 1 hour and cooling to room temperature, it was peeled off from the glass substrate to obtain a polyimide molded body (film). Table 2 shows the measurement results of the linear expansion coefficient, total light transmittance, glass transition temperature, and mechanical properties of the obtained polyimide molded body (film).

Experimental Example 4
A polyimide molded body (film) was obtained from the polyimide varnish obtained in Comparative Example 2 in the same manner as in Experimental Example 3. Table 2 shows the measurement results of the linear expansion coefficient, total light transmittance, glass transition temperature, and mechanical properties of the obtained polyimide molded body (film).

From Table 1, the polyimide resin of the present invention has excellent physical properties such as a low linear expansion coefficient of 60 ppm / K or less, a high total light transmittance of 87% or more, and a high glass transition temperature of 280 ° C. or more. it is obvious. The polyimide resin obtained in Comparative Example 1 has a low coefficient of linear expansion and a high glass transition temperature, but a low total light transmittance.

Moreover, the polyimide resin of this invention is a polyimide resin which has solvent solubility from Table 2, the low linear expansion coefficient of 60 ppm / K or less, the high total light transmittance of 87% or more, and the high glass transition temperature of 260 degreeC or more. It is clear that it has excellent physical properties. Although the solvent solubility of the polyimide resin of Comparative Example 2 is good, the total light transmittance is low.

That is, it can be seen that the polyimide resin of the present invention is a polyimide resin that simultaneously satisfies a low linear expansion coefficient, a high total light transmittance, and a high glass transition temperature.

Industrial application fields

The polyimide resin of the present invention has both high transparency, heat resistance and a low coefficient of linear expansion. Therefore, the polyimide molded body obtained by molding the polyimide varnish of the polyimide resin can be suitably used for optical materials such as displays and lighting. In addition, the polyimide resin can be used for heat-resistant insulating materials, heat-resistant paints, heat-resistant coating materials, and heat-resistant adhesives.

Claims

General formula (1)

A tetracarboxylic dianhydride represented by:
An aromatic diamine compound,
A polyimide resin obtained by imidation polymerization reaction in a molar ratio of the total of the diamine compounds with respect to the tetracarboxylic dianhydride 100 in the range of 90 to 110.
The aromatic diamine compound is represented by the general formula (2)

The polyimide resin of Claim 1 which is at least 1 sort (s) represented by the diamine compound.
Aromatic diamine compounds
(A) bis [4- (4-aminophenoxy) phenyl] sulfone, and (B) general formula (3)

The polyimide resin of Claim 1 which is at least 1 sort (s) represented by the diamine compound.
General formula (1)

A tetracarboxylic dianhydride represented by:
An aromatic diamine compound and an alicyclic diamine compound,
A polyimide resin obtained by imidation polymerization reaction in a molar ratio of the total of the diamine compounds with respect to the tetracarboxylic dianhydride 100 in the range of 90 to 110.
The alicyclic diamine compound has the general formula (4)

The polyimide resin according to claim 4, which is at least one kind represented by the diamine compound.
The aromatic diamine compound is represented by the general formula (2)

The polyimide resin according to claim 4 or 5, which is at least one kind represented by the diamine compound.
The aromatic diamine compound is represented by the general formula (5)

The polyimide resin according to claim 4 or 5, which is at least one kind represented by the diamine compound.
The aromatic diamine compound is represented by the general formula (6)

The polyimide resin according to claim 4 or 5, which is at least one kind represented by the diamine compound.
General formula (1)

A tetracarboxylic dianhydride represented by:
An aromatic diamine compound,
A polyamic acid resin obtained by copolymerization reaction with respect to the tetracarboxylic dianhydride 100 in a molar ratio of 90 to 110 in total.
The aromatic diamine compound is represented by the general formula (2)

The polyamic acid resin of Claim 9 which is at least 1 sort (s) represented by the diamine compound of these.
The aromatic diamine compound is represented by the general formula (5)

The polyamic acid resin of Claim 10 which is at least 1 type represented by the diamine compound.
General formula (1)

A tetracarboxylic dianhydride represented by:
An aromatic diamine compound and an alicyclic diamine compound,
A polyamic acid resin obtained by imidization polymerization reaction with respect to the tetracarboxylic dianhydride 100 in a molar ratio of 90 to 110 in total.
The alicyclic diamine compound has the general formula (4)

The polyamic acid resin of Claim 12 which is at least 1 sort (s) represented by the diamine compound.
The aromatic diamine compound is represented by the general formula (2)

The polyamic acid resin according to claim 12 or 13, which is at least one kind represented by the diamine compound.
A polyimide varnish containing the polyimide resin according to any one of claims 3 to 8 and an organic solvent.
A polyamic acid varnish containing the polyamic acid resin according to any one of claims 9 to 14 and an organic solvent.
A polyimide molded body obtained by molding the polyimide varnish according to claim 15.
A polyimide molded body obtained by molding the polyamic acid varnish according to claim 16.
The polyimide molded body according to claim 17 or 18, wherein the polyimide molded body is in the form of a film, a film, or a sheet.
A plastic substrate comprising the polyimide molded body according to any one of claims 17 to 19.
An electrical component or electronic component comprising the plastic substrate according to claim 20.