TW201920370A - Polyimide resin, polyimide varnish and polyimide film - Google Patents

Abstract

This invention provides a polyimide resin comprising a constituting unit A derived from a tetracarboxylic acid dianhydride and a constituting unit B derived from a diamine, wherein the constituting unit A contains a constituting unit (A-1) derived from a compound represented by the following formula (a-1), the constituting unit B contains a constituting unit (B-1) derived from a compound represented by the following formula (b-1) and a constituting unit (B-2) derived from a compound represented by the following formula (b-2), the ratio of constituting unit (A-1) in the constituting unit A is 50 mol% or more, the ratio of constituting unit (B-1) in the constituting unit B is 45 mol % or more and 85 mol% or less, and the ratio of constituting unit (B-2) in the constituting unit B is 15 mol% or more and 55 mol% or less. (In the formula (b-2), each R independently represents a hydrogen atom, a fluorine atom or a methyl group.).

Description

Polyimide resin, polyimide varnish, and polyimide film

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

Because polyimide resins have excellent mechanical properties and heat resistance, some people have explored various uses in the fields of electricity and electronic parts. For example, in order to reduce the weight and flexibility of the device, it is desirable to replace glass substrates used in image display devices such as liquid crystal displays and OLED displays with plastic substrates, and research on polyimide resins suitable for the plastic materials is also being conducted . Polyimide resins for such applications also need colorless transparency. In addition, in order to obtain a high-temperature process that can correspond to the manufacturing steps of image display devices, there is also a high dimensional stability of heat (that is, a low linear thermal expansion coefficient). Required.

As a polyfluorene imine resin having a low linear thermal expansion coefficient, for example, Patent Document 1 describes a composition containing a first tetracarboxylic acid component such as pyromellitic anhydride and 3,3 ', 4,4'-diphenylhydrazone. A polyimide resin obtained by synthesizing a second tetracarboxylic acid component such as a tetracarboxylic dianhydride and a ditoluidine fluorene skeleton diamine component. Patent Document 2 describes a diamine compound containing a benzoxazolyl group. Polyimide resin obtained by synthesis with aromatic tetracarboxylic dianhydride.
[Previous Technical Literature]
[Patent Literature]

[Patent Document 1] Japanese Patent Application Publication No. 2010-053336 [Patent Document 2] Japanese Patent Application Publication No. 2015-093915

[Questions to be solved by the invention]

In general, although polyimide resins are those with excellent mechanical properties and heat resistance, the structure of polyimide resins has been changed for the purpose of improving colorless transparency and further improving dimensional stability to heat. There is a possibility that these characteristics are impaired, and development of a polyimide resin having a good balance of mechanical properties, heat resistance, colorless transparency, and thermal dimensional stability is insufficient.
The object of the present invention is to provide a polyimide resin having good mechanical properties and heat resistance, colorless transparency, and excellent dimensional stability to heat.
[Means for solving problems]

The present inventors have found that a polyfluorene imide resin containing a combination of specific constituent units at a specific ratio can solve the above-mentioned problems, and completed the present invention.

That is, the present invention relates to the following [1] to [5].
[1] A polyimide resin containing 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),
This 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),
The proportion of the constituent unit (A-1) in the constituent unit A is 50 mol% or more,
The proportion of the constituent unit (B-1) in the constituent unit B is 45 mol% or more and 85 mol% or less.
The proportion of the constituent unit (B-2) in the constituent unit B is 15 mol% to 55 mol%.

[Chemized 1]

(In formula (b-2), R each independently represents a hydrogen atom, a fluorine atom, or a methyl group.)

[2] The polyimide resin according to [1], wherein the proportion of the constituent unit (A-1) in the constituent unit A is 100 mol%.
[3] The polyimide resin according to [1] or [2], wherein R represents a hydrogen atom.
[4] A polyimide varnish, which is obtained by dissolving a polyimide resin according to any one of [1] to [3] in an organic solvent.
[5] A polyimide film containing the polyimide resin according to any one of [1] to [3].
[Effect of Invention]

The polyimide resin of the present invention has good mechanical properties and heat resistance, is colorless and transparent, and has excellent dimensional stability to heat.

[Polyimide resin]
The polyfluorene imide resin of the present invention includes 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) derived from a compound represented by the following formula (a-1). -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). The proportion of the constituent unit (A-1) in the constituent unit A is 50 mol% or more, and the proportion of the constituent unit (B-1) in the constituent unit B is 45 mol% to 85 mol%. The constituent unit ( B-2) The proportion in the constituent unit B is 15 mol% or more and 55 mol% or less.

［Chemical 2］

(In formula (b-2), R each independently represents a hydrogen atom, a fluorine atom, or a methyl group.)

<Construction unit A>
The structural unit A is a structural unit derived from a tetracarboxylic dianhydride, and includes a structural unit (A-1) derived from a compound represented by the formula (a-1). The compound represented by the formula (a-1) is norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6,6 ''- Tetracarboxylic dianhydride. When the constituent unit A includes the constituent unit (A-1), heat resistance, colorless transparency, and dimensional stability are improved.
The proportion of the constituent unit (A-1) in the constituent unit A is 50 mol% or more. If the proportion of the constituent unit (A-1) is less than 50 mol%, there is a possibility that heat resistance, colorless transparency, and dimensional stability may deteriorate. The proportion of the constituent unit (A-1) is preferably 70 mol% or more, and more preferably 90 mol% or more. The upper limit 値 of the content ratio of the constituent unit (A-1) is not particularly limited, and is 100 mol%. The constitutional unit A may be constituted only by the constitutional unit (A-1).

The constituent unit A may include constituent units other than the constituent unit (A-1). The tetracarboxylic dianhydride which forms a structural unit other than the structural unit (A-1) is not particularly limited, and examples include pyromellitic dianhydride, 3,3 ', 4,4'-biphenyltetracarboxylic acid dianhydride Anhydrides, and aromatic tetracarboxylic dianhydrides such as 4,4 '-(hexafluoroisopropylidene) diphthalic anhydride; 1,2,3,4-cyclobutanetetracarboxylic dianhydride and 1,2,4 Alicyclic tetracarboxylic dianhydride such as 1,5-cyclohexanetetracarboxylic dianhydride (but excluding compounds represented by formula (a-1)); and 1,2,3,4-butanetetracarboxylic acid Aliphatic tetracarboxylic dianhydride such as acid dianhydride.
In the present 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 aromatics. Ring tetracarboxylic dianhydride, aliphatic tetracarboxylic dianhydride refers to tetracarboxylic dianhydride containing neither aromatic ring nor alicyclic ring.
The structural unit arbitrarily included in the structural unit A (that is, a structural unit other than the structural unit (A-1)) may be one type or two or more types.

<Construction unit B>
The structural unit B is a structural unit derived from a diamine, and 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). ).
The compound represented by formula (b-1) is 2,2'-bis (trifluoromethyl) benzidine. By including the structural unit (B-1) in the structural unit B, mechanical characteristics and dimensional stability are improved.
In the formula (b-2), each R is independently selected from the group consisting of a hydrogen atom, a fluorine atom, and a methyl group, and is preferably a hydrogen atom. Examples of the compound represented by the formula (b-2) include 9,9-bis (4-aminephenyl) fluorene, 9,9-bis (3-fluoro-4-aminephenyl) fluorene, and 9,9 -Bis (3-methyl-4-aminophenyl) fluorene and the like, preferably 9,9-bis (4-aminophenyl) fluorene. Since the constituent unit B includes the constituent unit (B-2), heat resistance is improved.

The proportion of the constituent unit (B-1) in the constituent unit B is 45 mol% to 85 mol%. If the proportion of the constituent unit (B-1) is less than 45 mol%, mechanical properties and / or dimensional stability may deteriorate, and if it exceeds 85%, heat resistance may deteriorate. The proportion of the constituent unit (B-1) is preferably 50 mol% or more and 80 mol% or less.
The proportion of the constituent unit (B-2) in the constituent unit B is 15 mol% to 55 mol%. If the proportion of the constituent unit (B-1) is less than 15 mol%, heat resistance may deteriorate, and if it exceeds 55%, mechanical properties and / or dimensional stability may deteriorate. The proportion of the constituent unit (B-2) is preferably 20 mol% to 50 mol%.
The total content ratio of the constituent unit (B-1) and the constituent unit (B-2) in the constituent unit B is 60 mol% or more, preferably 70 mol% or more, and more preferably 80% or more. The upper limit 値 of the total content ratio of the constituent unit (B-1) and the constituent unit (B-2) is not particularly limited, and is 100 mol%. The constituent unit B may be constituted by only the constituent unit (B-1) and the constituent unit (B-2).

The constituent unit B may contain constituent units other than the constituent units (B-1) and (B-2). The diamine forming such a structural unit is not particularly limited, and examples thereof include 1,4-phenylenediamine, p-xylylenediamine, 3,5-diaminobenzoic acid, and 2,2'-dimethyl Biphenyl-4,4'-diamine, 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 2,2-bis (4-aminophenyl) Hexafluoropropane, bis (4-aminophenyl) fluorene, 4,4'-diaminobenzylamine benzene, 1- (4-aminophenyl) -2,3-dihydroxy-1,3 , 3-trimethyl-1H-inden-5-amine, α, α'-bis (4-aminophenyl) -1,4-diisopropylbenzene, N, N'-bis (4-amine Phenyl) p-xylylenediamine, 4,4'-bis (4-aminophenoxy) biphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl] propane And aromatic diamines such as 2,2-bis (4- (4-aminophenoxy) phenyl) hexafluoropropane (except compounds represented by formula (b-1) and formula (b- 2) Compounds shown); alicyclic diamines such as 1,3-bis (aminomethyl) cyclohexane and 1,4-bis (aminomethyl) cyclohexane; and ethylenediamine and hexane Aliphatic diamines such as diamine.
In the present specification, the aromatic diamine means a diamine containing one or more aromatic rings, and the alicyclic diamine means a diamine containing one or more alicyclic rings and no aromatic ring, and an aliphatic diamine. Refers to diamines that do not contain aromatic or alicyclic rings.
The constituent units arbitrarily included in the constituent unit B (that is, constituent units other than the constituent units (B-1) and (B-2)) 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 100,000 in consideration of the mechanical strength of the obtained polyimide film. The number average molecular weight of the polyfluorene imine resin can be obtained, for example, by converting 値 into a standard polymethylmethacrylate (PMMA) measured by gel filtration chromatography.

The polyfluorene imide resin of the present invention has good mechanical properties and heat resistance, is colorless and transparent, and has excellent dimensional stability to heat, and can have the following physical properties:
The tensile strength of the polyimide resin of the present invention is preferably 80 MPa or more, more preferably 85 MPa or more, still more preferably 90 MPa or more, and even more preferably 95 MPa or more.
The tensile elastic modulus of the polyimide resin of the present invention is preferably 2.2 GPa or more, more preferably 2.4 GPa or more, still more preferably 2.5 GPa or more, and even more preferably 2.8 GPa or more.

The glass transition temperature (Tg) of the polyimide resin of the present invention is preferably 350 ° C or higher, more preferably 380 ° C or higher, still more preferably 400 ° C or higher, and particularly preferably 430 ° C or higher.

When the polyimide resin of the present invention is made into a polyimide film having a thickness of 10 μm, the total light transmittance is preferably 85% or more, more preferably 88%, more preferably 90% or more, and particularly preferably 91%. the above.
When the polyimide resin of the present invention is made into a polyimide film having a thickness of 10 μm, the yellow index (YI) is preferably 3.0 or less, more preferably 2.0 or less, still more preferably 1.5 or less, and even more preferably 1.2 or less.

The linear thermal expansion coefficient (CTE) of the polyfluorene imide resin of the present invention is preferably 25 ppm / ° C or lower, more preferably 20 ppm / ° C or lower, and more preferably 15 ppm / ° C or lower, based on a CTE of 100 to 200 ° C. , Especially 10ppm / ℃ or less; 100-350 ℃ CTE, 30ppm / ℃ or less, 25ppm / ℃ or less, 20ppm / ℃ or less, and 15ppm / ℃ or less .
The tensile elasticity coefficient, tensile strength, glass transition temperature (Tg), total light transmittance, yellow index (YI), and linear thermal expansion coefficient (CTE) in the present invention can be specifically described according to the examples. Method determination.

[Manufacturing method of polyimide resin]
The polyimide resin of the present invention can be obtained by providing a tetracarboxylic acid component containing the compound providing the above-mentioned constitutional unit (A-1), and 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).

As a compound which provides a structural unit (A-1), the compound represented by Formula (a-1) is mentioned, However, It is not limited to this, As long as it can form the same structural unit, its derivative may be sufficient. Examples of the derivative include a tetracarboxylic acid (i.e., norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 '' corresponding to a tetracarboxylic dianhydride represented by the formula (a-1). -Norbornane-5,5 '', 6,6 ''-tetracarboxylic acid), and alkyl esters of the tetracarboxylic acid. As a compound which provides a structural unit (A-1), the compound represented by Formula (a-1) (namely, dianhydride) is preferable.
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 form 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). As a compound which provides a structural unit (B-1), the compound (namely, a diamine) represented by Formula (b-1) is preferable.
As a compound which provides a structural unit (B-2), the compound represented by Formula (b-2) is mentioned, However, It is not limited to this, As long as it can form 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-2). As a compound which provides a structural unit (B-2), the compound (namely, a diamine) represented by Formula (b-2) is preferable.

The tetracarboxylic acid component contains 50 mol% or more of the compound providing the constituent unit (A-1), preferably 70 mol%, more preferably 90 mol% or more. The upper limit 値 of the content ratio 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 contain a compound other than the compound providing the constituent unit (A-1). Examples of the compound include the aforementioned aromatic tetracarboxylic dianhydride, alicyclic tetracarboxylic dianhydride, and aliphatic tetracarboxylic acid. Acid dianhydrides and their derivatives (tetracarboxylic acids, alkyl esters of tetracarboxylic acids, etc.).
The compound arbitrarily contained in the tetracarboxylic acid component (that is, a compound other than the compound providing the structural unit (A-1)) may be one kind or two or more kinds.

The diamine component contains 45 mol% to 85 mol% of the compound providing the constituent unit (B-1), preferably 50 mol% to 80 mol%. The diamine component contains 15 mol% or more and 55 mol% or less of the compound providing the constituent unit (B-2), preferably 20 mol% or more and 50 mol% or less.
The total of the diamine component containing the compound providing the constituent unit (B-1) and the compound providing the constituent unit (B-2) is 60 mol% or more, preferably 70 mol% or more, and more preferably 80 mol% or more . The upper limit 値 of the total content ratio 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 of only the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2).

The diamine component may contain 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 arbitrarily contained in the diamine component (that is, a compound other than the compound providing the structural unit (B-1) and the compound providing the structural unit (B-2)) may be one type or two or more types.

In the present invention, the feed ratio of the tetracarboxylic acid component to the diamine component used to manufacture the polyfluorene imine resin is preferably 0.9 to 1.1 mole relative to the tetracarboxylic acid component of 1 mole.

In addition, in the present invention, in the production of the polyfluorene imine resin, in addition to the tetracarboxylic acid component and the diamine component, a blocking agent may be used. As the capping agent, monoamines or dicarboxylic acids are preferred. In terms of the feeding amount of the introduced end-capping agent, 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. As the monoamine-based capping agent, for example, methylamine, ethylamine, propylamine, butylamine, benzylamine, 4-methylbenzylamine, 4-ethylbenzylamine, 4-dodecylbenzylamine, and 3-methylamine are recommended. Benzylamine, 3-ethylbenzylamine, aniline, 3-methylaniline, 4-methylaniline and the like. Among them, benzylamine and aniline are preferably used. As far as the dicarboxylic acid-type end-capping agent is concerned, it is preferably a dicarboxylic acid, and a part thereof may be closed. Recommendations such as 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 them, phthalic acid and phthalic anhydride can be preferably used.

The method for 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) feeding a tetracarboxylic acid component, a diamine component, and a reaction solvent to a reactor, stirring at room temperature to 80 ° C. for 0.5 to 30 hours, and then heating and performing 醯The method of the imidization reaction, (2) feeding the diamine component and the reaction solvent into the reactor and dissolving them, and then feeding the tetracarboxylic acid component, and stirring at room temperature to 80 ° C for 0.5 to 30 hours as required Then, a method of raising the temperature and carrying out the amidine imidization reaction, (3) a method of feeding a tetracarboxylic acid component, a diamine component, and a reaction solvent into the reactor, immediately raising the temperature and performing the amidine imidization reaction, and the like.

The reaction solvent used in the production of the polyfluorene imine resin may be any one that does not interfere with the fluorene imine reaction and can dissolve the generated polyfluorene imine. Examples thereof 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, and N-methyl Limonamine-based solvents such as caprolactam, 1,3-dimethylimidazolidone, and tetramethylurea; lactone-based solvents such as γ-butyrolactone and γ-valerolactone; hexamethylphosphoramidene, Phosphorus-containing ammonium solvents such as hexamethylphosphinetriamine; sulfur-containing solvents such as dimethylfluorene, dimethylsulfinium, and cyclobutane; ketones such as acetone, cyclohexane, and methylcyclohexane Solvents; amine solvents such as methylpyridine and pyridine; 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, 2,6-xylenol, 3,4-xylenol, 3,5-xylenol, etc.
Specific examples of the ether-based solvent include 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, and 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, methyl ethyl carbonate, ethylene carbonate, and propyl carbonate.
Among the above-mentioned reaction solvents, a fluorene-based solvent or a lactone-based solvent is more preferable. Moreover, the said reaction solvent can also be used individually or in mixture of 2 or more types.

In the amidation reaction, it is preferable to use a Dean-Stark device or the like to perform the reaction while removing water generated during production. By carrying out such an operation, the degree of polymerization and the rate of imidization can be further improved.

In the 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, triethylamine, and trimethylpyridine. Organic base catalysts such as propylamine, 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, and p-toluenesulfonic acid. Acid, naphthalenesulfonic acid, etc. The said sulfonium imidization catalyst can be used individually or in combination of 2 or more types.
Among the above, from the viewpoint of operability, it is preferable to use an alkali catalyst, an organic alkali catalyst is more suitable, and triethylamine is more suitable, and triethylamine and triethylenediamine are particularly preferably used in combination.

醯 The temperature of the imidization reaction, considering the reaction rate and the inhibition of gelation, is preferably 120 to 250 ° C, and more preferably 160 to 200 ° C. The reaction time is preferably 0.5 to 10 hours after the start of the distillation of the produced 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 dissolved in the organic solvent.
The organic solvent is not particularly limited as long as it can dissolve polyimide resin. As a reaction solvent for producing polyimide resin, it is preferable to use two or more of the above compounds alone or in combination.
Since the polyimide resin of the present invention has solvent solubility, it can be made into a high concentration varnish which is stable at room temperature. The polyimide varnish of the present invention preferably contains 5 to 40% by mass of the polyimide resin of the present invention, and more preferably 10 to 30% by mass. The viscosity of polyimide varnish is preferably 1 to 200 Pa ～ s, and more preferably 5 to 150 Pa ･ s.
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 the like, as long as the required characteristics of the polyimide film are not impaired. Surfactant, leveling agent, defoaming agent, fluorescent whitening agent, cross-linking agent, polymerization initiator, photosensitizer and other additives.
The manufacturing method of the polyimide varnish of this invention is not specifically limited, A well-known method can be applied.

[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 has good mechanical properties and heat resistance, and is colorless and transparent, and has excellent dimensional stability to heat.
The method for producing the polyimide film of the present invention is not particularly limited, and a known method can be used. For example, a method of coating the polyimide varnish of the present invention or forming a thin film, and then removing the organic solvent can be exemplified.

The polyimide film of the present invention has excellent mechanical properties and heat resistance, is colorless and transparent, and has excellent dimensional stability against heat. It can be ideally used as a color filter, a flexible display, a semiconductor part, and an optical device. Film for various components such as components. 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 in any way by these examples.
The solid content concentration of the polyimide varnish obtained in the examples and comparative examples and the physical properties of the polyimide film were measured by the methods shown below.

(1) Measurement of solid content concentration The solid content concentration of polyimide varnish is measured by using a small electric furnace "MMF-1" manufactured by AS ONE Co., Ltd. at a temperature of 320 ° C for 120 min. The difference between the masses before and after the sample was calculated.
(2) Film thickness The film thickness was measured using a micrometer manufactured by Mitutoyo Co., Ltd.
(3) The tensile strength and the coefficient of tensile elasticity were measured in accordance with JIS K7127 using a tensile tester "StrographVG-1E" manufactured by Toyo Seiki Co., Ltd.
(4) Glass transition temperature (Tg)
Using a thermomechanical analyzer "TMA / SS6100" manufactured by Hitachi High-Tech Science Co., Ltd., the temperature was increased to above Tg in a 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. Residual stress was removed, and then TMA measurement was performed under the same conditions from 50 ° C to 500 ° C to obtain Tg.
(5) Full light transmittance, yellow index (YI)
The measurement was performed in accordance with JIS K7361-1 using a color and turbidity measuring instrument "COH400" manufactured by Nippon Denshoku Industries Co., Ltd.
(6) Linear thermal expansion coefficient (CTE)
TMA measurement was performed using a thermomechanical analyzer "TMA / SS6100" manufactured by Hitachi High-Tech Science Co., Ltd. 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 in a tensile mode. A CTE of 100 to 200 ° C and a CTE of 100 to 350 ° C are obtained.

<Example 1>
16.012 g (0.050 mol) was placed in a 300 mL 5-neck 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. 2,2'-bis (trifluoromethyl) benzidine (manufactured by Wakayama Seika Co., Ltd.), 17.423 g (0.050 mol) of 9,9-bis (4-aminephenyl) pyrene (Tadaoka Chemical Industrial Co., Ltd.) and 85.688 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), and the solution was obtained by stirring at a temperature of 70 ° C. under a nitrogen atmosphere at a rotation speed of 200 rpm.
In this solution, 38.438 g (0.100 mol) of norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6, After 6 ''-tetracarboxylic dianhydride (manufactured by JX Energy Co., Ltd.) and 21.422 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), 0.506 g of triethylammonium as an ammonium imidization catalyst was added. Amine (manufactured by Kanto Chemical Co., Ltd.) and 0.056 g of triethylene glycol diamine (manufactured by Tokyo Chemical Industry Co., Ltd.), and heated by a mantle heater, the temperature in the reaction system was raised to about 20 minutes 190 ° C. The distilled components were collected, and the rotation speed was adjusted in accordance with the increase in viscosity, while the temperature in the reaction system was maintained at 190 ° C and refluxed for 5 hours.
Thereafter, 169.87 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added, and the temperature in the reaction system was cooled to 120 ° C., followed by stirring for about 3 hours to homogenize, and a solid content concentration of 20% by mass was obtained. Polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate, and maintained at 80 ° C. for 20 minutes with a hot plate, and then heated at 400 ° C. for 30 minutes in a hot air dryer under a nitrogen atmosphere to evaporate the solvent. A thin film having a thickness of 10 μm was obtained. The results are shown in Table 1.

<Example 2>
A 300 mL 5-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 25.619 g (0.080 mol). 2,2'-bis (trifluoromethyl) benzidine (manufactured by Wakayama Seiki Chemical Industry Co., Ltd.), 6.969 g (0.020 mol) of 9,9-bis (4-aminephenyl) pyrene (Tadaoka Chemical Industrial Co., Ltd.), 86.703 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation), and the solution was obtained by stirring at a temperature of 70 ° C. under a nitrogen atmosphere at a rotation speed of 200 rpm.
In this solution, 38.438 g (0.100 mol) of norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6, After 6 ''-tetracarboxylic dianhydride (manufactured by JXenergy Co., Ltd.) and 21.676 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), 0.506 g of triethylamine was used as a sulfonium imidization catalyst. (Manufactured by Kanto Chemical Co., Ltd.) and 0.056 g of triethylene glycol diamine (manufactured by Tokyo Chemical Industry Co., Ltd.), and heated with a heating bag, and the temperature inside the reaction system was raised to 190 ° C over about 20 minutes. The distilled components were collected, and the rotation speed was adjusted in accordance with the increase in viscosity, while the temperature in the reaction system was maintained at 190 ° C and refluxed for 5 hours.
Thereafter, 169.82 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added, and the internal temperature of the reaction system was cooled to 120 ° C., followed by stirring for about 3 hours to homogenize, and a solid content concentration of 20% by mass was obtained. Polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate, and maintained at 80 ° C. for 20 minutes with a hot plate, and then heated at 400 ° C. for 30 minutes in a hot air dryer under a nitrogen atmosphere to evaporate the solvent. A thin film having a thickness of 10 μm was obtained. The results are shown in Table 1.

<Example 3>
In a 300 mL 5-neck 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, put 22.417 g (0.070 mol) 2,2'-bis (trifluoromethyl) benzidine (manufactured by Wakayama Seika Chemical Co., Ltd.), 10.454 g (0.030 mol) of 9,9-bis (4-aminephenyl) fluorene (Tadaoka Chemical Industrial Co., Ltd.), 85.570 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), and the solution was obtained by stirring at a system temperature of 70 ° C. under a nitrogen atmosphere at a rotation speed of 200 rpm.
In this solution, 38.438 g (0.100 mol) of norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6, After 6 ''-tetracarboxylic dianhydride (manufactured by JX energy Co., Ltd.) and 21.392 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), 0.506 g of triethylammonium as an ammonium imidization catalyst was added. Amine (manufactured by Kanto Chemical Co., Ltd.) and 0.056 g of triethylene glycol diamine (manufactured by Tokyo Chemical Industry Co., Ltd.) were heated in a heating bag, and the temperature in the reaction system was raised to 190 ° C over about 20 minutes. The distilled components were collected, and the rotation speed was adjusted in accordance with the viscosity increase, while the temperature in the reaction system was maintained at 190 ° C, and refluxed for 3 hours.
Thereafter, 163.855 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added, and the internal temperature of the reaction system was cooled to 120 ° C., followed by stirring for about 3 hours to homogenize, and a solid content concentration of 20% by mass was obtained. Polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate, and maintained at 80 ° C. for 20 minutes with a hot plate, and then heated at 400 ° C. for 30 minutes in a hot air dryer under a nitrogen atmosphere to evaporate the solvent. A thin film having a thickness of 10 μm was obtained. The results are shown in Table 1.

〈Comparative example 1〉
34.845 g (0.100 mol) was placed in a 300 mL 5-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. 9,9-bis (4-aminophenyl) pyrene (manufactured by Tanoka Chemical Industry Co., Ltd.), 88.395 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), the temperature in the system is 70 ° C. and nitrogen Then, the solution was stirred at a rotation speed of 200 rpm.
In this solution, 38.438 g (0.100 mol) of norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6, After 6 ''-tetracarboxylic dianhydride (manufactured by JX Energy Co., Ltd.) and 22.099 g of butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), 0.506 g of triethylamine (as a sulfonium imidization catalyst) was added. Manufactured by Kanto Chemical Co., Ltd.) and 0.056 g of triethylene glycol diamine (manufactured by Tokyo Chemical Industry Co., Ltd.), and heated with a heating bag, and the temperature inside the reaction system was raised to 190 ° C in about 20 minutes. The distilled components were collected, and the rotation speed was adjusted in accordance with the increase in viscosity, while the temperature in the reaction system was maintained at 190 ° C and refluxed for 5 hours.
Thereafter, 169.74 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added, and the internal temperature of the reaction system was cooled to 120 ° C., followed by stirring for about 3 hours to homogenize, to obtain a solid content concentration of 20 mass% Polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate, and maintained at 80 ° C. for 20 minutes with a hot plate, and then heated at 400 ° C. for 30 minutes in a hot air dryer under a nitrogen atmosphere to evaporate the solvent. A thin film having a thickness of 10 μm was obtained. The results are shown in Table 1.

〈Comparative example 2〉
3.202 g (0.010 mol) was placed in a 300 mL 5-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. 2,2'-bis (trifluoromethyl) benzidine (manufactured by Wakayama Seika Chemical Industry Co., Ltd.), 31.361 g (0.090 mol) of 9,9-bis (4-aminephenyl) pyrene (Tadaoka Chemical Industrial Co., Ltd.), 87.601 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), and the solution was obtained by stirring at a temperature of 70 ° C. under a nitrogen atmosphere at a rotation speed of 200 rpm.
In this solution, 38.438 g (0.100 mol) of norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6, After 6 ''-tetracarboxylic dianhydride (manufactured by JX energy Co., Ltd.) and 21.900 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), 0.506 g of triethylammonium as an imidization catalyst was added. Amine (manufactured by Kanto Chemical Co., Ltd.) and 0.056 g of triethylene glycol diamine (manufactured by Tokyo Chemical Industry Co., Ltd.) were heated in a heating bag, and the temperature in the reaction system was raised to 190 ° C over about 20 minutes. The distilled components were collected, and the rotation speed was adjusted in accordance with the increase in viscosity, while the temperature in the reaction system was maintained at 190 ° C and refluxed for 5 hours.
Thereafter, 168.086 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added, and the internal temperature of the reaction system was cooled to 120 ° C., followed by stirring for about 3 hours to homogenize, and a solid content concentration of 20% by mass was obtained. Polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate, and maintained at 80 ° C. for 20 minutes with a hot plate, and then heated at 400 ° C. for 30 minutes in a hot air dryer under a nitrogen atmosphere to evaporate the solvent. A thin film having a thickness of 10 μm was obtained. The results are shown in Table 1.

〈Comparative example 3〉
In a 300 mL 5-neck 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, 9.607 g (0.030 mol) was charged. 2,2'-bis (trifluoromethyl) benzidine (manufactured by Wakayama Seika Chemical Co., Ltd.), 24.392 g (0.070 mol) of 9,9-bis (4-aminephenyl) pyrene (Tadaoka Chemical Industrial Co., Ltd.) and 86.924 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), and the solution was obtained by stirring at a temperature of 70 ° C. under a nitrogen atmosphere at a rotation speed of 200 rpm.
In this solution, 38.438 g (0.100 mol) of norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6, After 6 ''-tetracarboxylic dianhydride (manufactured by JX Energy Co., Ltd.) and 21.731 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Co., Ltd.), 0.506 g of triethylammonium as an ammonium imidization catalyst was added. Amine (manufactured by Kanto Chemical Co., Ltd.) and 0.056 g of triethylene glycol diamine (manufactured by Tokyo Chemical Industry Co., Ltd.) were heated in a heating bag, and the temperature in the reaction system was raised to 190 ° C over about 20 minutes. The distilled components were collected, and the rotation speed was adjusted in accordance with the increase in viscosity, while the temperature in the reaction system was maintained at 190 ° C and refluxed for 5 hours.
After that, 166.676 g of γ-butyrolactone (manufactured by Mitsubishi Chemical Corporation) was added, and the temperature in the reaction system was cooled to 120 ° C., and then stirred for about 3 hours to homogenize to obtain a solid content concentration of 20 mass% Polyimide varnish. Then, the obtained polyimide varnish was coated on a glass plate, and maintained at 80 ° C. for 20 minutes with a hot plate, and then heated at 400 ° C. for 30 minutes in a hot air dryer under a nitrogen atmosphere to evaporate the solvent. A thin film having a thickness of 10 μm was obtained. The results are shown in Table 1.

[Table 1]

The abbreviations in the table are as follows.
CpODA: norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 ''-norbornane-5,5 '', 6,6 ''-tetracarboxylic dianhydride (formula (a -1) compound shown)
TFMB: 2,2'-bis (trifluoromethyl) benzidine (compound represented by formula (b-1))
BAFL: 9,9-bis (4-aminophenyl) fluorene (compound represented by formula (b-2))

As shown in Table 1, the polyimide films of Examples 1 to 3 had good mechanical properties and heat resistance, and were excellent in colorless transparency and dimensional stability to heat. In contrast, although the polyimide films of Comparative Examples 1 to 3 are excellent in heat resistance, they have very low dimensional stability against heat.

Claims (5)

A polyfluorene imide resin comprising 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) derived from a compound represented by the following formula (a-1). -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) The proportion of the constituent unit (A-1) in the constituent unit A is 50 mol% or more, and the proportion of the constituent unit (B-1) in the constituent unit B is 45 mol% or more and 85 mol%. Hereinafter, the proportion of the constituent unit (B-2) in the constituent unit B is 15 mol% or more and 55 mol% or less. In formula (b-2), R each independently represents a hydrogen atom, a fluorine atom, or a methyl group. For example, the polyimide resin according to item 1 of the patent application scope, wherein the proportion of the constituent unit (A-1) in the constituent unit A is 100 mole%. For example, a polyfluorene imine resin according to item 1 or 2 of the patent application scope, wherein R represents a hydrogen atom. A polyimide varnish is obtained by dissolving a polyimide resin as described in any one of the claims 1 to 3 in an organic solvent. A polyimide film comprising the polyimide resin according to any one of claims 1 to 3 of the scope of patent application.