KR20160091935A - Polyimide precursor composition, method for producing polyimide, polyimide, polyimide film, and substrate - Google Patents

Abstract

The present invention relates to a polyimide precursor composition containing a phosphorus compound containing a polyimide precursor and a phosphorus atom and having a boiling point at 1 atm lower than the decomposition temperature and at most 350 ° C.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyimide precursor composition, a method of producing a polyimide, a polyimide, a polyimide film,

The present invention relates to a solution composition (polyimide precursor composition) containing a polyimide precursor capable of obtaining polyimide excellent in transparency and mechanical properties and also excellent in heat resistance, and a process for producing polyimide. The present invention also relates to a polyimide, a polyimide film and a substrate which are excellent in transparency and mechanical properties and also excellent in heat resistance.

2. Description of the Related Art In recent years, along with the advent of a highly information-oriented society, optical materials such as optical alignment films for liquid crystal display devices and protective films for color filters, such as optical fibers and optical waveguides in the field of optical communication, have been developed. Particularly in the field of display devices, there has been actively studied a plastic substrate which is lightweight and excellent in flexibility as a substitute for a glass substrate, and a display capable of bending or rounding. For this reason, there is a demand for a higher-performance optical material that can be used for such applications.

The aromatic polyimide is essentially colored yellowish brown by the formation of an intramolecular conjugate or a charge transfer complex. Therefore, as means for suppressing coloring, for example, introduction of fluorine atoms into a molecule, imparting flexibility to the main chain, introduction of a bulk group as a side chain, and the like inhibit intramolecular conjugation or formation of a charge transfer complex And a method of expressing transparency has been proposed. For example, Patent Document 1 discloses an aromatic polyimide containing a fluorine atom and having high transparency.

Also, a method of expressing transparency by using a ring-cyclic or battery cyclic polyimide which does not form a charge-transfer complex in principle is also proposed. For example, Patent Documents 2 to 4 disclose a ring-cyclic polyimide having high transparency using an aromatic tetracarboxylic acid dianhydride as a tetracarboxylic acid component and an alicyclic diamine as a diamine component.

Also, for example, Patent Documents 5 to 8 disclose various ring-cyclic polyimides having high transparency using alicyclic tetracarboxylic acid dianhydride as the tetracarboxylic acid component and aromatic diamine as the diamine component .

Patent Documents 9 and 10 disclose a polyimide using decahydro-1,4: 5,8-dimethanonaphthalene-2,3,6,7-tetracarboxylic acid as a tetracarboxylic acid component have. Non-Patent Document 1 discloses a polyacetal resin composition comprising as a tetracarboxylic acid component a poly (ethyleneglycol) resin obtained by using (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2t, 3t, 6c, (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2c, 3c, 6c, 7c-tetra Polyimides using carboxylic acids are disclosed.

Non-Patent Document 3 discloses that a tetracarboxylic acid component is selected from the group consisting of norbornane-2-spiro-a-cyclopentanone-a'-spiro-2'-norbornane-5,5 ' '-Tetracarboxylic acid dianhydride is disclosed. Further, the norbornane-2-spiro-a-cyclopentanone-a'-spiro-2''-norbornane-5,5 '', 6,6 "-tetracarboxylic acid 2 It is described that an anhydride contains six kinds of stereoisomers. Patent Document 11 also discloses that, as a tetracarboxylic acid component, norbornane-2-spiro-a-cyclopentanone-a'-spiro-2'-norbornane-5,5 ' -Tetracarboxylic acid dianhydride. ≪ / RTI >

The alicyclic tetracarboxylic acid dianhydride as the tetracarboxylic acid component and the ring-cyclic polyimide using the aromatic diamine as the diamine component have high transparency, bending resistance and high heat resistance, but depending on the application, A polyimide having higher heat resistance is required.

On the other hand, Patent Document 12 discloses that a tetracarboxylic acid component containing 3,3 ', 4,4'-biphenyltetracarboxylic dianhydride as a main component and a tetracarboxylic acid component containing 3,3', 4,4'-biphenyltetracarboxylic dianhydride as a main component and a diamine component containing paraphenylenediamine as a main component A polyamic acid solution composition containing polyamic acid and a phosphorus compound is cast on a substrate and subjected to heat treatment to produce a polyimide laminate having a thickness of less than 50 mu m and containing phosphorus and forming a polyimide layer containing phosphorus Method is disclosed. The phosphorus compounds used in the examples of Patent Document 12 are triphenyl phosphate, monoethyl phosphate, monolauryl phosphate, and polyphosphoric acid. Patent Document 12 describes that a high heat-resistant polyimide layer in which thermal decomposition is suppressed in a temperature range of 500 ° C to 650 ° C can be formed by this production method.

Japanese Laid-Open Patent Publication No. 2011-074384 Japanese Patent Application Laid-Open No. 2003-192787 Japanese Patent Application Laid-Open No. 2004-83814 Japanese Laid-Open Patent Publication No. 2008-308550 Japanese Patent Application Laid-Open No. 2003-168800 International Publication No. 2008/146637 Japanese Laid-Open Patent Publication No. 2002-69179 Japanese Patent Application Laid-Open No. 2002-146021 Japanese Patent Application Laid-Open No. 2007-2023 Japanese Patent Application Laid-Open No. 6-51316 International Publication No. 2011/099518 International Publication No. 2012/173204

 Macromolecules, Vol. 27, No. 5, P1117-1123, 1994  Macromolecules, Vol. 32, No. 15, P4933-4939, 1999  Polymer Journal, Vol. 68, No. 3, P. 127-131 (2011)

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a polyimide precursor composition (a solution containing a polyimide precursor) which is a polyimide excellent in transparency and mechanical properties, Composition), and a process for producing polyimide.

The present invention relates to each of the following items.

1. A polyimide precursor comprising at least one of a repeating unit represented by the following formula (1), a repeating unit represented by the following formula (2), or a repeating unit represented by the following formula (3)

Phosphorus atom, and has a boiling point at 1 atm lower than the decomposition temperature, and further contains a phosphorus compound at 350 deg. C or lower.

[Chemical Formula 1]

(Wherein X < _{1 >} Is a quadrivalent group having an alicyclic structure, Y ₁ And R &_lt; ₂ > are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkyl silyl group having 3 to 9 carbon atoms.

(2)

(Wherein X ₂ is a tetravalent group having an aromatic ring, Y ₂ is a divalent group having an alicyclic structure, R ₃ and R ₄ are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, 9 < / RTI >

(3)

(Wherein X ₃ is a tetravalent group having an aromatic ring and Y ₃ is a divalent group having an aromatic ring provided that at least one of X ₃ and Y ₃ contains a fluorine atom and R ₅ and R ₆ Are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.

2. The polyimide precursor composition according to item 1, wherein the phosphorus compound has a boiling point of 200 占 폚 or less at 1 atm.

3. The polyimide precursor composition according to item 1 or 2 above, wherein the phosphorus compound is any one of trimethyl phosphate, trimethyl phosphite, dimethyl phosphite, and diethyl phosphite.

4. A method for producing a polyimide, which comprises heat-treating the polyimide precursor composition according to any one of items 1 to 3 to imidize the polyimide precursor.

5. A process for producing a polyimide precursor composition comprising the steps of applying the polyimide precursor composition described in any one of items 1 to 3 on a substrate,

A step of heat-treating the polyimide precursor composition on the substrate to imidize the polyimide precursor

Wherein the polyimide precursor is a polyimide precursor.

6. A polyimide produced by the method according to item 4 or 5 above.

7. A polyimide film produced by the method according to item 4 or 5 above.

8. A substrate for a display, a touch panel, or a solar cell, comprising the polyimide described in the above item 6 or the polyimide film described in the above item 7.

According to the present invention, a polyimide precursor composition (solution composition containing a polyimide precursor) that can obtain a polyimide having higher heat resistance even with the same composition as polyimide excellent in transparency and mechanical properties, and a method of producing polyimide Can be provided.

The polyimide (polyimide of the present invention) obtained from the polyimide precursor composition of the present invention has high transparency, has higher heat resistance, has a low thermal expansion coefficient and is easy to form a fine circuit, Can be preferably used. The polyimide of the present invention can also be preferably used for forming a substrate for a touch panel or a solar cell.

The polyimide precursor composition of the present invention contains a polyimide precursor containing at least one of repeating units represented by the above-mentioned formula (1), repeating units represented by the above formula (2), or repeating units represented by the above formula (3) , A phosphorus compound whose boiling point at 1 atm is lower than the decomposition temperature and which is 350 DEG C or lower. The polyimide precursor containing the repeating unit represented by the formula (1) and the polyimide precursor containing the repeating unit represented by the formula (2) are precursors of the ring-cyclic polyimide, and the repeating unit represented by the formula (3) The unit polyimide precursor is a precursor of an aromatic polyimide containing a fluorine atom.

A polyimide obtained from a polyimide precursor containing at least one of the repeating unit represented by the above-mentioned formula (1), the repeating unit represented by the above formula (2), or the repeating unit represented by the above formula (3) , And fluorine atom-containing aromatic polyimide have high transparency. In the case of such a highly transparent polyimide, the use of an additive such as a phosphorus compound which can cause coloring is not preferred. However, even when a phosphorus compound whose boiling point at 1 atm is lower than the decomposition temperature and further at 350 DEG C or lower, particularly preferably at 200 DEG C or lower is added to the polyimide precursor composition, the transparency of the obtained polyimide is not inhibited, And further improved. That is, according to the present invention, a polyimide having higher heat resistance can be obtained while maintaining high transparency from a polyimide precursor having the same composition. In the case of a compound in which the phosphorus compound added to the polyimide precursor composition has a boiling point higher than the decomposition temperature at 1 atmospheric pressure such as phosphoric acid or a phosphorus compound such as triphenyl phosphate at a boiling point of more than 350 ° C , The transparency of the obtained polyimide is lowered.

As described above, the polyimide precursor composition of the present invention contains at least one of the repeating unit represented by the above-mentioned formula (1), the repeating unit represented by the above formula (2), or the repeating unit represented by the above formula (3) Lt; / RTI > polyimide precursor.

X ₁ in the above formula (1) is preferably a tetravalent group having an alicyclic structure having 4 to 40 carbon atoms, and Y ₁ is preferably a divalent group having an aromatic ring having 6 to 40 carbon atoms.

Examples of the tetracarboxylic acid component imparting the repeating unit of the above formula (1) include 1,2,3,4-cyclobutane tetracarboxylic acid, isopropylidenediphenoxy bisphthalic acid, cyclohexane-1 , 2,4,5-tetracarboxylic acid, [1,1'-non (cyclohexane)] -3,3 ', 4,4'-tetracarboxylic acid, [1,1'- )] - 2,3,3 ', 4'-tetracarboxylic acid, [1,1'-non (cyclohexane)] - 2,2', 3,3'-tetracarboxylic acid, (Cyclohexane-1,2-dicarboxylic acid), 4,4 '- (propane-2,2-diyl) bis (cyclohexane- (Cyclohexane-1,2-dicarboxylic acid), 4,4'-thiobis (cyclohexane-1,2-dicarboxylic acid), 4,4'-sulfonylbis (cyclohexane- Dicarboxylic acid), 4,4 '- (dimethylsilanediyl) bis (cyclohexane-1,2-dicarboxylic acid), 4,4' - (tetrafluoropropane- -Diyl) bis (cyclohexane-1,2-dicarboxylic acid), octahydropentalene-1,3,4,6-tetra Heptane-2,3,5,6-tetracarboxylic acid, 6- (carboxymethyl) bicyclo [2.2.1] heptane-2,3,5-tricarboxylic acid Acid, bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic acid, bicyclo [2.2.2] octa-5-ene-2,3,7,8-tetracarboxylic acid, Tricyclo [4.2.2.02,5] decane-3,4,7,8-tetracarboxylic acid, tricyclo [4.2.2.02,5] deca-7-ene-3,4,9,10-tetracarboxylic Tetracarboxylic acid, norbornane-2-spiro-a-cyclopentanone-a'-spiro-2 ', 4'- '-Norbornane 5,5' ', 6,6 "-tetracarboxylic acid, (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2c, 3c, 6c, Tetracarboxylic acid, (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2t, 3t, 6c, 7c-tetracarboxylic acid or their tetracarboxylic acid 2 Anhydrides, tetracarboxylic acid silyl esters, tetracarboxylic acid esters , It may be a derivative, such as tetracarboxylic acid chloride. The tetracarboxylic acid component may be used singly or in combination of a plurality of species.

Examples of the diamine component giving the repeating unit of the above formula (1) include p-phenylenediamine, m-phenylenediamine, benzidine, 3,3'-diamino-biphenyl, 2,2'-bis (Trifluoromethyl) benzidine, 3,3'-bis (trifluoromethyl) benzidine, m-tolidine, 4,4'-diaminobenzanilide, 3,4'- diaminobenzanilide, N, N (4-aminophenyl) terephthalamide, N, N'-p-phenylenebis (p- aminobenzamide), 4-aminophenoxy-4-diaminobenzoate, bis (P-aminobenzoate), bis (4-aminophenyl) - [1,1 '] thiophene, terephthalate, biphenyl-4,4'- dicarboxylic acid bis -Biphenyl] -4,4'-dicarboxylate, [1,1'-biphenyl] -4,4'-diyl bis (4-aminobenzoate), 4,4'-oxydianiline, 3 , 4'-oxydianiline, 3,3'-oxydianiline, p-methylenebis (phenylenediamine), 1,3-bis (4-aminophenoxy) benzene, Bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) Bis (4-aminophenyl) sulfone, 3, 4-aminophenyl) sulfone, 2, , 3'-bis (trifluoromethyl) benzidine, 3,3'-bis ((aminophenoxy) phenyl) propane, 2,2'-bis (3-amino-4-hydroxyphenyl) hexafluoropropane , Bis (4- (4-aminophenoxy) diphenyl) sulfone, bis (4- (3-aminophenoxy) diphenyl) sulfone, octafluorobenzidine, 3,3'-dimethoxy- Diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,4- Aminoanilino) -6-amino-1,3,5-triazine, 2,4-bis (4-aminoanilino) (4-aminoanilino) -6-ethylamino-1,3,5-triazine, 2,4-bis (4- No) and the Lino-1,3,5-triazine-6 not. The diamine component may be used singly or in combination of plural kinds.

The polyimide precursor containing at least one of the repeating units represented by the above formula (1) may contain other repeating units other than the repeating unit represented by the above formula (1). The tetracarboxylic acid component and the diamine component for imparting other repeating units are not particularly limited and other known aromatic or aliphatic tetracarboxylic acids, known aromatic or aliphatic diamines can be used. Other tetracarboxylic acid components may be used alone, or a plurality of species may be used in combination. The other diamine components may be used singly or in combination of plural kinds.

The content of other repeating units other than the repeating unit represented by the above formula (1) is preferably 30 mol% or less, or 30 mol% or less, more preferably 20 mol% or less, Is preferably 10 mol% or less.

X ₂ in the formula (2) is preferably a tetravalent group having an aromatic ring having 6 to 40 carbon atoms, and Y ₂ is preferably a divalent group having an alicyclic structure having 4 to 40 carbon atoms.

Examples of the tetracarboxylic acid component for imparting the repeating unit of the above formula (2) include 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane, 4- (2,5-dioxo Yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid, pyromellitic acid, 3,3 ', 4,4'-benzophenonetetracarboxylic acid , 3,3 ', 4,4'-biphenyltetracarboxylic acid, 2,3,3', 4'-biphenyltetracarboxylic acid, 4,4'-oxydiphthalic acid, bis (3,4- Dicarboxyphenyl) sulfone dianhydride, m-terphenyl-3,4,3 ', 4'-tetracarboxylic acid dianhydride, p-terphenyl-3,4,3'4'-tetracarboxylic acid 2 A tetracarboxylic acid dianhydride, a tetracarboxylic acid silyl ester, a tetracarboxylic acid ester, a tetracarboxylic acid chloride or the like can be used as the acid anhydride, anhydride, biscarboxyphenyldimethylsilane, bisdicarboxyphenoxydiphenylsulfide, And derivatives thereof. The tetracarboxylic acid component may be used singly or in combination of a plurality of species.

Examples of the diamine component giving the repeating unit of the above formula (2) include 1,4-diaminocyclohexane, 1,4-diamino-2-methylcyclohexane, 1,4- 1,4-diamino-2-n-propylcyclohexane, 1,4-diamino-2-n-propylcyclohexane, 1,4-diamino-2-sec-butylcyclohexane, 1,4-diamino-2-tert-butylcyclohexane, 1,2-diaminocyclohexane , 1,3-diaminocyclobutane, 1,4-bis (aminomethyl) cyclohexane, 1,3-bis (aminomethyl) cyclohexane, diaminobicycloheptane, diaminomethylbicycloheptane, diaminooxy (Aminocyclohexyl) methane, bis (aminocyclohexyl) isopropylidene 6, bis (aminocyclohexyl) aminocycloheptane, diaminocyclododecane, Bis (3-aminophenoxy) -3,3,3 ', 3'-tetramethyl-1,1'-spirobiindane, 6,6'-bis 3,3 ', 3'-tetramethyl-1,1'-spirobiindane. The diamine component may be used singly or in combination of plural kinds.

The polyimide precursor containing at least one of the repeating units represented by the above formula (2) may contain other repeating units other than the repeating unit represented by the above formula (2). The tetracarboxylic acid component and the diamine component for imparting other repeating units are not particularly limited and other known aromatic or aliphatic tetracarboxylic acids, known aromatic or aliphatic diamines can be used. Other tetracarboxylic acid components may be used alone, or a plurality of species may be used in combination. The other diamine components may be used singly or in combination of plural kinds.

The content of other repeating units other than the repeating units represented by the above-mentioned general formula (2) is preferably 30 mol% or less, or 30 mol% or less, more preferably 20 mol% or less, Is preferably 10 mol% or less.

As X ₃ in the formula (3), a tetravalent group having an aromatic ring having 6 to 40 carbon atoms is preferable, and as Y ₃ , a bivalent group having an aromatic ring having 6 to 40 carbon atoms is preferable. One of X ₃ and Y ₃ may contain a fluorine atom, and both of X ₃ and Y ₃ may contain a fluorine atom.

Examples of the fluorine atom-containing tetracarboxylic acid component giving the repeating unit of the above formula (3) include 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane, A tetracarboxylic acid dianhydride, a tetracarboxylic acid silyl ester, a tetracarboxylic acid ester, and a tetracarboxylic acid chloride. As the tetracarboxylic acid component containing no fluorine atom, for example, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1 , 2-dicarboxylic acid, pyromellitic acid, 3,3 ', 4,4'-benzophenonetetracarboxylic acid, 3,3', 4,4'-biphenyltetracarboxylic acid, 4,4'-oxydiphthalic acid, bis (3,4-dicarboxyphenyl) sulfone dianhydride, m-terphenyl-3,4,3 ', 4'-biphenyltetracarboxylic acid, -Tetracarboxylic acid dianhydride, p-terphenyl-3,4,3 ', 4'-tetracarboxylic acid dianhydride, biscarboxyphenyldimethylsilane, bisdicarboxyphenoxydiphenylsulfide, sulfonyldiphthalic acid, And derivatives of these tetracarboxylic acid dianhydrides, tetracarboxylic acid silyl esters, tetracarboxylic acid esters, and tetracarboxylic acid chlorides. The tetracarboxylic acid component may be used singly or in combination of a plurality of species.

Examples of the fluorine atom-containing diamine component giving the repeating unit of the above formula (3) include 2,2'-bis (trifluoromethyl) benzidine, 3,3'-bis (trifluoromethyl Bis (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 2,2'- Amino-4-hydroxyphenyl) hexafluoropropane. Examples of the diamine component containing no fluorine atom include p-phenylenediamine, m-phenylenediamine, benzidine, 3,3'-diamino-biphenyl, m- (4-aminophenyl) terephthalamide, N, N'-p-phenylenebis (p-aminobenzamide), 4'-diaminobenzanilide (4-aminophenyl) terephthalate, biphenyl-4,4'-dicarboxylic acid bis (4-aminophenyl) ester, p-phenylenebis -Aminobenzoate), bis (4-aminophenyl) - [1,1'-biphenyl] -4,4'-dicarboxylate, [1,1'- (4-aminobenzoate), 4,4'-oxydianiline, 3,4'-oxydianiline, 3,3'-oxydianiline, p-methylenebis Bis (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) benzene, ) Biphenyl, 4,4 Bis ((aminophenoxy) phenyl) propane, bis (4- (4-aminophenoxy) Phenyl) sulfone, bis (4- (3-aminophenoxy) diphenyl) sulfone, octafluorobenzidine, 3,3'-dimethoxy-4,4'- diaminobiphenyl, 3,3'- Diaminobiphenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 2,4-bis (4-aminoanilino) -6- 5-triazine, 2,4-bis (4-aminoanilino) -6-methylamino-1,3,5-triazine, 2,4- 1,3,5-triazine, and 2,4-bis (4-aminoanilino) -6-anilino-1,3,5-triazine. The diamine component may be used singly or in combination of plural kinds.

The polyimide precursor containing at least one of the repeating units represented by the above formula (3) may contain other repeating units other than the repeating unit represented by the above formula (3). The tetracarboxylic acid component and the diamine component for imparting other repeating units are not particularly limited and other known aromatic or aliphatic tetracarboxylic acids, known aromatic or aliphatic diamines can be used. Other tetracarboxylic acid components may be used alone, or a plurality of species may be used in combination. The other diamine components may be used singly or in combination of plural kinds.

The content of other repeating units other than the repeating units represented by the above-described general formula (3) is preferably 30 mol% or less, or 30 mol% or less, more preferably 20 mol% or less, Is preferably 10 mol% or less.

The polyimide precursor may contain at least one repeating unit represented by the above formula (1) and at least one repeating unit represented by the above formula (2), and at least one repeating unit represented by the above formula (1) (3), and at least one of the repeating units represented by the above-mentioned formula (2) and at least one repeating unit represented by the above formula (3) Or at least one of the repeating units represented by the formula (1) and at least one repeating unit represented by the formula (2), and at least one repeating unit represented by the formula (3) May be contained. In this case, the content of other repeating units other than the repeating units represented by the above-mentioned formulas (1), (2) and (3) is preferably 30 mol% or less or 30 mol% More preferably 20 mol% or less, and further preferably 10 mol% or less.

In one embodiment, the polyimide precursor is, for example, a polyimide precursor containing a repeating unit represented by the following formula (1-1-1), more preferably a polyimide precursor containing a repeating unit represented by the following formula (1-1-2) Lt; / RTI > precursors are preferred.

[Chemical Formula 4]

(Wherein A ₁ is a divalent group having an aromatic ring and R ₁ and R ₂ are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.)

[Chemical Formula 5]

(Wherein A ₁ is a divalent group having an aromatic ring and R ₁ and R ₂ are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.)

In the above formulas (1-1-1) and (1-1-2), one of the acid groups at the 2-position or the 3-position of the decahydro-1,4: 5,8-dimethanonaphthalene ring is (--CONH-) formed by the reaction with an amino group, one group represented by -COOR ₁ in which _one of the groups does not form an amide bond, and one acid group at the 6-position or the 7-position is reacted with an amino group to form an amide bond -CONH-), and one of them is a group represented by -COOR ₂ which does not form an amide bond. That is, in the formula (1-1-1) and the formula (1-1-2), four structural isomers, that is, (i) a group represented by -COOR ₁ at the 2-position and -CONH- at the 3 -position A group represented by -COOR ₂ at the 6-position, a group represented by -CONH-A ₁ - at the 7-position, (ii) a group represented by -COOR ₁ at the 3-position and a group represented by -CONH- at the 2-position , A group represented by -COOR ₂ at the 6-position and a group represented by -CONH-A ₁ - at the 7-position, (iii) a group represented by -COOR ₁ at the 2-position and a group represented by -CONH- at the 3-position , A group represented by -COOR ₂ at the 7-position and a group represented by -CONH-A ₁ - at the 6-position, (iv) a group represented by -COOR ₁ at the 3-position and a group represented by -CONH- at the 2- All of those having a group represented by -COOR ₂ at the 7-position, and those represented by -CONH-A ₁ - at the 6 -position.

The polyimide precursor is preferably a polyimide precursor represented by the formula (1-1-1) wherein A ₁ is a group represented by the following formula (1-1-A), more preferably a repeating unit represented by the formula (1-1-2) It is preferable to contain the species.

[Chemical Formula 6]

(Wherein m ₁ represents an integer of 0 to 3 and n ₁ represents an integer of 0 to 3, respectively.) V ₁ , U ₁ and T ₁ each independently represent a hydrogen atom, a methyl group, a trifluoromethyl group Z ₁ and W ₁ each independently represents a direct bond or a group selected from the group consisting of groups represented by the formula: -NHCO-, -CONH-, -COO-, and -OCO-, Lt; / RTI >

In other words, in one embodiment, the polyimide precursor is selected from the group consisting of decahydro-1,4: 5,8-dimethanonaphthalene-2,3,6,7-tetracarboxylic acids, , 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2t, 3t, 6c, 7c-tetracarboxylic acids (such as tetracarboxylic acids and the like, tetracarboxylic acid and tetracarboxylic acid 2 Tetracarboxylic acid ester, tetracarboxylic acid chloride and the like) and a diamine component having an aromatic ring, more preferably a tetracarboxylic acid component containing an aromatic ring, A polyimide precursor obtained from a diamine component containing a diamine component giving a repeating unit of the formula (1-1-1) or (1-1-2) wherein A ₁ is a group represented by the above formula (1-1-A) to be.

Examples of the tetracarboxylic acid component for imparting the repeating unit of the above formula (1-1-1) include decahydro-1,4: 5,8-dimethanonaphthalene-2,3,6,7-tetracarboxylic acids May be used alone, or a plurality of species may be used in combination. Examples of the tetracarboxylic acid component giving the repeating unit of the above formula (1-1-2) include (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2t, 3t, 6c, Tetracarboxylic acids, and the like can be used singly or in combination of plural kinds.

The diamine component giving the repeating unit of the formula (1-1-1) or the formula (1-1-2) is preferably a diamine-containing compound in which A ₁ is a group represented by the formula (1-1-A) .

The diamine component giving a repeating unit of the formula (1-1-1) or (1-1-2) in which A ₁ is a group represented by the above formula (1-1-A) has an aromatic ring, And a plurality of aromatic rings are connected to each other independently by a direct bond, an amide bond, or an ester bond. The connection position of the directional rings is not particularly limited, but the structure is linearized by bonding at the four positions with respect to the connecting group of the amino group or the aromatic ring, and the obtained polyimide may undergo low-line thermal expansion. The aromatic ring may be substituted with a methyl group or a trifluoromethyl group. The substitution position is not particularly limited.

The diamine component giving the repeating unit of the formula (1-1-1) or the formula (1-1-2) in which A ₁ is a group represented by the above formula (1-1-A) is not particularly limited, For example, there may be mentioned p-phenylenediamine, m-phenylenediamine, benzidine, 3,3'-diamino-biphenyl, 2,2'-bis (trifluoromethyl) benzidine, N'-bis (4-aminophenyl) terephthalamide, N, N'-dicyclohexylcarbodiimide, aminophenoxy-4-diaminobenzoate, bis (4-aminophenyl) terephthalate, biphenyl-4,4'-dicarboxylic acid bis (p-aminobenzamide) (4-aminophenyl) - [1,1'-biphenyl] -4,4'-dicarboxylate, [1 , 1'-biphenyl] -4,4'-diyl bis (4-aminobenzoate), and the like, And it may also be used in combination of plural kinds. Of these, p-phenylenediamine, m-tolidine, 4,4'-diaminobenzanilide, 4-aminophenoxy-4-diaminobenzoate, 2,2'-bis (trifluoromethyl) benzidine (4-aminophenyl) terephthalamide and biphenyl-4,4'-dicarboxylic acid bis (4-aminophenyl) ester are preferable, and p-phenylenediamine, 4, 4'-diaminobenzanilide, and 2,2'-bis (trifluoromethyl) benzidine are more preferable. By using p-phenylenediamine, 4,4'-diaminobenzanilide and 2,2'-bis (trifluoromethyl) benzidine as the diamine component, the resulting polyimide has both high heat resistance and high transmittance. These diamines may be used singly or in combination of plural kinds. o-Tolidine is not preferable in view of high risk.

A diamine component giving the A ₁ in the formula (1-1-1) or the formula (1-1-2) (that is, the diamine component of the formula (1-1-1) or the formula (1-1-2) A diamine component giving a repeating unit), other diamines other than the diamine component in which A ₁ has the structure of the above formula (1-1-A) can be used in combination. As other diamine components, other aromatic or aliphatic diamines can be used. For example, 4,4'-oxydianiline, 3,4'-oxydianiline, 3,3'-oxydianiline, p-methylenebis (phenylenediamine), 1,3- (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'- Bis (4-aminophenoxy) phenyl) hexafluoropropane, 2,2-bis (4-aminophenoxy) Bis ((aminophenoxy) phenyl) propane, 2,2'-bis (3-aminophenyl) sulfone, 3,3'-bis (trifluoromethyl) benzidine, (4-aminophenoxy) diphenyl) sulfone, bis (4- (4-aminophenoxy) diphenyl) sulfone, bis (4- , 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, 3,3'-difluoro- Diaminobiphenyl, 1,4-diaminocyclohexane, 1,4-diamino-2-methyl Cyclohexane, 1,4-diamino-2-ethylcyclohexane, 1,4-diamino-2-n-propylcyclohexane, 1,4-diamino-2-isopropylcyclohexane, Diamino-2-tert-butylcyclohexane, 1,4-diamino-2-tert-butylcyclohexane, (Aminomethyl) cyclohexane, 1,3-bis (aminomethyl) cyclohexane, diaminobicyclopentane, 1,3-diaminocyclohexane, 1,2-diaminocyclohexane, (Aminocyclohexyl) methane, bis (aminocyclohexyl) methane, bis (aminocyclohexyl) methane, diisobutylaluminum, (Aminocyclohexyl) isopropylidene 6,6'-bis (3-aminophenoxy) -3,3,3 ', 3'-tetramethyl-1,1'-spirobiindane, 6,6'-bis (4-aminophenoxy) -3,3,3 ', 3'-tetramethyl-1,1'-spiro Or the like may be mentioned indan derivatives thereof, be used alone, may also be used in combination of plural kinds. Of these, 4,4'-oxydianiline, 3,4'-oxydianiline, 3,3'-oxydianiline, p-methylenebis (phenylenediamine), 1,3- Bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 4'-bis (3-aminophenoxy) biphenyl is preferable, and 4,4'-bis (4-aminophenoxy) biphenyl is particularly preferable.

The polyimide precursor of the present invention is a polyimide precursor wherein, in 100 mol% of the repeating unit represented by the above formula (1-1-1) or the above formula (1-1-2), A ₁ is represented by the above formula (1-1-A) Is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 70 mol% or more, in terms of the total of repeating units represented by the formula (1-1-1) or (1-1-2) More preferably 90 mol% or more, and particularly preferably 100 mol%. When the proportion of the repeating unit represented by the formula (1-1-1) or (1-1-2) in which A ₁ is a group represented by the above formula (1-1-A) is smaller than 50 mol%, the polyimide The linear thermal expansion coefficient may be increased.

In one embodiment, from the viewpoint of the properties of the obtained polyimide, among the diamine component giving 100 moles of the repeating unit of the above formula (1-1-1) or the above formula (1-1-2) Is preferably 70 mol% or less, more preferably 80 mol% or less, and still more preferably 90 mol% or less, based on the total amount of the diamine component . For example, other diamines such as diamines having an ether bond (-O-) such as 4,4'-oxydianiline and 4,4'-bis (4-aminophenoxy) For example, up to 40 mol%, preferably up to 30 mol%, and more preferably up to 30 mol%, based on 100 mol% of the diamine component giving the repeating unit of the formula (1-1-1) Or less, preferably 20 mol% or less, more preferably 10 mol% or less.

As described above, in the polyimide precursor containing the repeating unit represented by the formula (1-1-1) or the formula (1-1-2) of the present invention, in the formula (1-1-1) or It is preferable that A ₁ in the formula (1-1-2) is the above-mentioned formula (1-1-A). In other words, when the diamine component giving the repeating unit of the above formula (1-1-1) or the above formula (1-1-2) is a compound represented by the formula (1-A) wherein A ₁ is a group represented by the above formula -1-1) or a diamine component giving a repeating unit of the formula (1-1-2). A diamine component giving the A ₁ in the formula (1-1-1) or the formula (1-1-2) (that is, the diamine component of the formula (1-1-1) or the formula (1-1-2) Is a diamine component giving a repeating unit of the formula (1-1-1) or (1-1-2) wherein A ₁ is a group represented by the above formula (1-1-A) , The heat resistance of the obtained polyimide is improved.

In one embodiment, the polyimide precursor containing the repeating unit represented by the above formula (1-1-1) or (1-1-2) of the present invention is a polyimide precursor wherein A ₁ is a repeating unit represented by the above formula (1-1- (1-1-1) or (1-1-2), which is a group represented by the formula (A). In other words, when the diamine component giving the repeating unit of the above formula (1-1-1) or the above formula (1-1-2) is a compound represented by the formula (1-A) wherein A ₁ is a group represented by the above formula -1-1) or a diamine component which gives a repeating unit of the formula (1-1-2). A diamine component giving the A ₁ in the formula (1-1-1) or the formula (1-1-2) (that is, the diamine component of the formula (1-1-1) or the formula (1-1-2) A diamine component giving a repeating unit) contains at least two kinds of diamine components in which A ₁ gives the structure of the above formula (1-1-A), the balance between the high transparency and the low linear expansion properties of the obtained polyimide (That is, a polyimide having a high transparency and a low thermal expansion coefficient can be obtained).

In this embodiment, for example, the polyimide precursor containing the repeating unit represented by the formula (1-1-1) or the formula (1-1-2) -1) or a diamine component giving A ₁ in the above formula (1-1-2) (that is, a diamine component giving the repeating unit of the above formula (1-1-1) or the above formula (1-1-2) Component) contains at least two kinds of diamine components in which A ₁ gives the structure of the above formula (1-1-A), and one of them is preferably 4,4'-diaminobenzanilide. The diamine component giving A ₁ in the formula (1-1-1) or the formula (1-1-2) contains at least two diamine components giving the structure of the formula (1-1-A) And one of them is 4,4'-diaminobenzanilide, polyimide having both high transparency and low linear thermal expansion as well as high heat resistance can be obtained.

In one embodiment, the polyimide precursor containing the repeating unit represented by the formula (1-1-1) or the formula (1-1-2) of the present invention is a polyimide precursor represented by the formula (1-1-1) or (I.e., a diamine component giving the repeating unit of the above formula (1-1-1) or the above formula (1-1-2)) to A ₁ in the above formula (1-1-2) , 2'-bis (trifluoromethyl) benzidine and p-phenylenediamine, and 4,4'-diaminobenzanilide. By combining these diamine components, a polyimide having high transparency, low heat expansion, and heat resistance is obtained.

In this embodiment, a diamine component (that is, a compound represented by the above formula (1-1-1) or the formula (1) in which the A ₁ in the formula (1-1-1) or the formula -1-2)) preferably contains 20 mol% or more and 80 mol% or less of 4,4'-diaminobenzanilide, and further contains p-phenylenediamine and More preferably 20 mol% or more and 80 mol% or less in any one or both of 2,2'-bis (trifluoromethyl) benzidine, and more preferably 4,4'-diaminobenzanilide And 30 mol% or more and 70 mol% or less in any one or both of p-phenylenediamine and 2,2'-bis (trifluoromethyl) benzidine, , Particularly preferably 4,4'-diaminobenzanilide is contained in an amount of not less than 40 mol% and not more than 60 mol% , P- phenylenediamine (trifluoromethyl) diamine and 2,2'-bis it is more preferred to contain in either one, or both in at least 40 mol% and not more than 60 mol% of benzidine.

The polyimide precursor of the present invention may contain other repeating units other than the repeating units represented by the above formula (1-1-1) or (1-1-2).

As the tetracarboxylic acid component for imparting other repeating units, other aromatic or aliphatic tetracarboxylic acids may be used. For example, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane, 4- (2,5-dioxotetrahydrofuran-3-yl) Hydroxynaphthalene-1,2-dicarboxylic acid, pyromellitic acid, 3,3 ', 4,4'-benzophenonetetracarboxylic acid, 3,3', 4,4'-biphenyltetracarboxylic acid, (3,4-dicarboxyphenyl) sulfone dianhydride, m-terphenyl-3,4,3, 4,3'-biphenyltetracarboxylic acid, 4,4'-oxydiphthalic acid, ', 4'-tetracarboxylic acid dianhydride, p-terphenyl-3,4,3', 4'-tetracarboxylic acid dianhydride, biscarboxyphenyldimethylsilane, bisdicarboxyphenodydiphenylsulfide, sulfo 1,2,4-cyclobutanetetracarboxylic acid, isopropylidene diphenoxy bisphthalic acid, cyclohexane-1,2,4,5-tetracarboxylic acid, [1,1'-bis (Cyclohexane)] -3,3 ', 4,4'-tetracarboxylic acid, [1,1'-non (cyclohexane)] - 2,3,3' 1,1'-bis (cyclohexane)] - 2,2 ', 3,3'-te (Cyclohexane-1,2-dicarboxylic acid), 4,4'- (propane-2,2-diyl) bis (cyclohexane-1,2-dicarboxylic acid (Cyclohexane-1,2-dicarboxylic acid), 4,4'-thiobis (cyclohexane-1,2-dicarboxylic acid), 4,4'-oxybis (Cyclohexane-1,2-dicarboxylic acid), 4,4'- (dimethylsilanediyl) bis (cyclohexane-1,2-dicarboxylic acid), 4,4'- (Tetrafluoropropane-2,2-diyl) bis (cyclohexane-1,2-dicarboxylic acid), octahydropentalene-1,3,4,6-tetracarboxylic acid, bicyclo [2.2. Heptane-2,3,5-tricarboxylic acid, bicyclo [2.2.2] heptane-2,3,5,6-tetracarboxylic acid, 6- (carboxymethyl) bicyclo [ Octane-2,3,5,6-tetracarboxylic acid, bicyclo [2.2.2] octa-5-ene-2,3,7,8-tetracarboxylic acid, tricyclo [4.2.2.02,5] Decane-3,4,7,8-tetracarboxylic acid, tricyclo [4.2.2.02,5] deca-7-ene-3,4,9,10-tetracarboxylic acid , 9-oxatricyclo [4.2.1.02,5] nonane-3,4,7,8-tetracarboxylic acid, norbornane-2-spiro-a-cyclopentanone- - norbornane 5,5 ", 6,6" -tetracarboxylic acid, (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2c, 3c, 6c, 7c -Tetracarboxylic acid and the like, and acid dianhydrides thereof, and they may be used alone or in combination of a plurality of species. Among them, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid, bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic acid, Spiro- [alpha] -cyclopentanone- [alpha] -spiro-2 " -norbornane 5,5 ", 6,6 "- tetracarboxylic acid, (4arH, 8acH) 1t, 4t: 5c, 8c-dimethanonaphthalene-2c, 3c, 6c, 7c-tetracarboxylic acid, and the like, and acid dianhydrides thereof are preferable because the polyimide can be easily produced and the heat resistance Is more preferable in terms of superiority. These acid dianhydrides may be used singly or in combination of plural kinds.

The diamine component for imparting another repeating unit is preferably a diamine component for giving a repeating unit of the formula (1-1-1) or (1-1-2) wherein A ₁ is a group represented by the above formula (1-1-A) May be a diamine exemplified as a diamine.

As the diamine component giving another repeating unit, other aromatic or aliphatic diamines can be used. For example, 4,4'-oxydianiline, 3,4'-oxydianiline, 3,3'-oxydianiline, p-methylenebis (phenylenediamine), 1,3- (4-aminophenoxy) benzene, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'- Bis (4-aminophenoxy) phenyl) hexafluoropropane, 2,2-bis (4-aminophenoxy) Bis ((aminophenoxy) phenyl) propane, 2,2'-bis (3-aminophenyl) sulfone, 3,3'-bis (trifluoromethyl) benzidine, (4-aminophenoxy) diphenyl) sulfone, bis (4- (4-aminophenoxy) diphenyl) sulfone, bis (4- , 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, 3,3'-difluoro- Diaminobiphenyl, 1,4-diaminocyclohexane, 1,4-diamino-2-methyl Cyclohexane, 1,4-diamino-2-ethylcyclohexane, 1,4-diamino-2-n-propylcyclohexane, 1,4-diamino-2-isopropylcyclohexane, Diamino-2-tert-butylcyclohexane, 1,4-diamino-2-tert-butylcyclohexane, (Aminomethyl) cyclohexane, 1,3-bis (aminomethyl) cyclohexane, diaminobicyclopentane, 1,3-diaminocyclohexane, 1,2-diaminocyclohexane, (Aminocyclohexyl) methane, bis (aminocyclohexyl) methane, bis (aminocyclohexyl) methane, diisobutylaluminum, (Aminocyclohexyl) isopropylidene 6,6'-bis (3-aminophenoxy) -3,3,3 ', 3'-tetramethyl-1,1'-spirobiindane, 6,6'-bis (4-aminophenoxy) -3,3,3 ', 3'-tetramethyl-1,1'-spiro Or the like may be mentioned indan derivatives thereof, be used alone, may also be used in combination of plural kinds.

In one embodiment, the polyimide precursor contains the repeating unit represented by the above formula (1-1-1) or the above formula (1-1-2) in a total amount of preferably 50 mol% or more, Or more, more preferably 70 mol% or more, further preferably 90 mol% or more, and particularly preferably 100 mol%. When the proportion of the repeating unit represented by the above formula (1-1-1) or the above formula (1-1-2) is 50 mol% or more, the film forming property is improved and the coefficient of linear thermal expansion of the obtained polyimide is extremely small. From the viewpoint of the total light transmittance, the repeating unit represented by the formula (1-1-1) or the repeating unit represented by the formula (1-1-2) out of 100 mol% of the total repeating units is preferably 50 mol% 99 mol% or less, more preferably 60 mol% or more to 95 mol% or less, particularly preferably 70 mol% or more to 95 mol% or less.

In another embodiment, the polyimide precursor is preferably a polyimide precursor containing, for example, a repeating unit represented by the following formula (1-2-1), and is preferably a polyimide precursor represented by the following formula (1-2-2) (1-2-3), and the total content of the repeating units represented by the formulas (1-2-2) and (1-2-3) in the repeating unit represented by the formula (1-2-3) More preferably, the polyimide precursor is 80 mol% or more.

(7)

(Wherein A ₂ is a divalent group having an aromatic ring and R ₁ and R ₂ are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.)

[Chemical Formula 8]

(Wherein A ₂ is a divalent group having an aromatic ring and R ₁ and R ₂ are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.)

[Chemical Formula 9]

(Wherein A ₂ is a divalent group having an aromatic ring and R ₁ and R ₂ are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms.)

(1-2-1), the formula (1-2-2) and the formula (1-2-3) are the same as those in the case where two norbornane rings (bicyclo [2.2.1] heptane) A group represented by -COOR &_lt; _{1 &gt}; or a group represented by -COOR &_lt; ₂ > in which one of the acid groups at the 5-position or 6-position reacts with the amino group to form an amide bond (-CONH-) . That is, has the formula (1-2-1), formula (1-2-2) and the formula (1-2-3), the four structural isomers, namely (i) represented by -COOR ₁ in the 5-position Group having a group represented by -CONH- at the 6-position and a group represented by -COOR ₂ at the 5'-position and -CONH-A ₂ - at the 6'-position, (ii) ₁ has a group represented by -CONH- at the 5-position, a group represented by -COOR ₂ at the 5 'position and -CONH-A ₂ - at the 6' position, (iii) Having a group represented by -COOR ₁ at the 6-position with -CONH-, a group represented by -COOR ₂ at the 6 'position and -CONH-A ₂ - at the 5' Having a group represented by -COOR ₁ at the 6-position, -CONH- at the 5-position, a group represented by -COOR ₂ at the 6 'position and -CONH-A ₂ - at the 5' Everything is included.

The polyimide precursor is preferably a repeating unit represented by the formula (1-2-1) wherein A ₂ is a group represented by the following formula (1-2-A), more preferably A ₂ is a repeating unit represented by the following formula (1-2-A (1-2-2) and / or (1-2-3) which is a group represented by the formula (1-2).

[Chemical formula 10]

(Wherein m ₂ represents an integer of 0 to 3 and n ₂ represents an integer independently of 0 to 3. V ₂ , U ₂ and T ₂ each independently represent a hydrogen atom, a methyl group, a trifluoromethyl group Z ₂ and W ₂ each independently represents a direct bond or a group selected from the group consisting of a group represented by the formula: -NHCO-, -CONH-, -COO-, and -OCO-, Lt; / RTI >

In other words, in some embodiments, the polyimide precursor is selected from the group consisting of norbornane-2-spiro-a-cyclopentanone-a'-spiro- '' -Tetracarboxylic acids and the like, more preferably trans-endo-endo-norbornane-2-spiro-a-cyclopentanone- ', 6,6''- tetracarboxylic acids and / or cis-endo-endo-norbornane-2-spiro-a-cyclopentanone-a'-spiro- , 5 '', 6,6 '' - tetracarboxylic acids (such as tetracarboxylic acids and the like, tetracarboxylic acid and tetracarboxylic acid dianhydride, tetracarboxylic acid silylester, tetracarboxylic acid ester, A tetracarboxylic acid component containing a tetracarboxylic acid derivative such as a tetracarboxylic acid derivative represented by the above formula (1-2-A), and a diamine component having an aromatic ring, more preferably A ₂ Is a polyimide precursor obtained from a diamine component containing a diamine component giving a repeating unit of the formula (1-2-1), the formula (1-2-2) or the formula (1-2-3).

Examples of the tetracarboxylic acid component giving the repeating unit of the above formula (1-2-1) include norbornane-2-spiro-α-cyclopentanone-α'-spiro-2 "-norbornane- , 5 ", and 6,6" -tetracarboxylic acids may be used alone or in combination of two or more. Examples of the tetracarboxylic acid component imparting the repeating unit of the above formula (1-2-2) include trans-endo-endo-norbornane-2-spiro-a-cyclopentanone- -Norbornane-5,5 ", and 6,6 " -tetracarboxylic acids may be used alone or in combination of two or more. Examples of the tetracarboxylic acid component giving the repeating unit of the above formula (1-2-3) include cis-endo-endo-norbornane-2-spiro-a-cyclopentanone- -Norbornane-5,5 ", and 6,6 " -tetracarboxylic acids may be used alone or in combination of two or more.

In a more preferred form of the polyimide precursor, a tetracarboxylic acid component (trans-endo-endo-norbornane-2-spiro-a-cyclo Pentane-α'-spiro-2 "-norbornane-5,5", 6,6 "-tetracarboxylic acids, and the like) 3) as a repeating unit of a tetracarboxylic acid component (cis-endo-endo-norbornane-2-spiro-a-cyclopentanone-a'-spiro-2''-norbornane- ), Tetracarboxylic acids and the like) may be used, and a tetracarboxylic acid component (trans-endo-endo -Norbornane-2-spiro-? -Cyclopentanone-? '- spiro-2 "-norbornane-5,5", 6,6 "-tetracarboxylic acids, etc.) And a tetracarboxylic acid component (cis-endo- endo-norbornane-2-spiro- [alpha] -cyclopentanone- [alpha] ' -spiro-2 " -norbornane-5,5 ", 6,6 " -tetracarboxylic acids) Or both of them may be used.

The polyimide precursor preferably has a total content of repeating units represented by the above formulas (1-2-2) and (1-2-3) in an amount of 80 mol% or more based on the total repeating units, that is, At least one repeating unit represented by the formula (1-2-2) and the repeating unit represented by the above formula (1-2-3), and the repeating unit is contained in the total repeating units in a total amount, preferably 80% , Preferably 90 mol% or more, more preferably 95 mol% or more, and particularly preferably 99 mol% or more. , At least one repeating unit represented by the above general formula (1-2-2) and the above general formula (1-2-3), and the repeating unit is contained in the total repeating units in a total amount, preferably 80 mol% The coefficient of linear thermal expansion of the resulting polyimide is reduced.

The above formula (1-2-1), or formula (1-2-2), the diamine component that gives the repeating unit represented by the above formula (1-2-3) are, A ₂ has the formula (1-2- A). ≪ / RTI >

A diamine component (A- ₂ ) which gives a repeating unit of the formula (1-2-1), the formula (1-2-2), or the formula (1-2-3) Has an aromatic ring and, when having a plurality of aromatic rings, the aromatic rings are connected to each other independently by a direct bond, an amide bond or an ester bond. The connection position of the directional rings is not particularly limited, but the structure is linearized by bonding at the four positions with respect to the connecting group of the amino group or the aromatic ring, and the obtained polyimide may undergo low-line thermal expansion. The aromatic ring may be substituted with a methyl group or a trifluoromethyl group. The substitution position is not particularly limited.

A diamine component (A- ₂ ) which gives a repeating unit of the formula (1-2-1), the formula (1-2-2), or the formula (1-2-3) But are not limited to, for example, p-phenylenediamine, m-phenylenediamine, benzidine, 3,3'-diamino-biphenyl, 2,2'-bis (trifluoromethyl) benzidine , 4,4'-diaminobenzanilide, N, N'-bis (4-amino (2-aminoethyl) Phenyl) terephthalamide, N, N'-p-phenylenebis (p-aminobenzamide), 4-aminophenoxy-4-diaminobenzoate, bis , 4'-dicarboxylic acid bis (4-aminophenyl) ester, p-phenylene bis (p- aminobenzoate), bis Dicarboxylate, [1,1'-biphenyl] -4,4'-diyl bis (4-aminobenzoate), and the like. Or a combination of plural species may be used. Of these, p-phenylenediamine, m-tolidine, 4,4'-diaminobenzanilide, 4-aminophenoxy-4-diaminobenzoate, 2,2'-bis (trifluoromethyl) benzidine (4-aminophenyl) terephthalamide and biphenyl-4,4'-dicarboxylic acid bis (4-aminophenyl) ester are preferable, and p-phenylenediamine, 4, 4'-diaminobenzanilide, and 2,2'-bis (trifluoromethyl) benzidine are more preferable. By using p-phenylenediamine, 4,4'-diaminobenzanilide, and 2,2'-bis (trifluoromethyl) benzidine as the diamine component, the obtained polyimide has both high heat resistance and high transmittance. These diamines may be used singly or in combination of plural kinds. In one embodiment, it is excluded that only one kind of diamine component is 4,4'-diaminobenzanilide. In one embodiment, the diamine component is a mixture of 4,4'-diaminobenzanilide and the compound of formula (1-2-1) wherein A ₂ is a structure other than the above formula (1-2-A) 1-2-2), a diamine component to give the repeating unit of the above formula (1-2-3) (other diamine other than the diamine component in which A ₂ gives the structure of the above formula (1-2-A) ) Can be excluded. In addition, o-tolidine is not preferable in view of high risk.

As the diamine component giving the repeating unit of the above formula (1-2-1), or the above formula (1-2-2) and the above formula (1-2-3), A ₂ is a repeating unit represented by the formula (1-2- Other diamines other than the diamine component giving the structure of the compound (A) can be used in combination. As other diamine components, other aromatic or aliphatic diamines can be used. Examples of the other diamine component include 4,4'-oxydianiline, 3,4'-oxydianiline, 3,3'-oxydianiline, bis (4-aminophenyl) sulfide, p- (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 2,2 Bis (4-aminophenyl) sulfone, 3,3-bis (4-aminophenoxy) phenyl] hexafluoropropane, bis (4-aminophenoxy) phenyl) propane, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, bis (3-aminophenoxy) diphenyl) sulfone, octafluorobenzidine, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dichloro-4,4'- Phenyl, 3,3'-difluoro-4,4'-diaminobiphenyl, 9,9-bis (4-aminophenyl) fluorene, 4,4'- , 4,4'-bis (3-aminophenoxy) Biphenyl, 1,4-diaminocyclohexane, 1,4-diamino-2-methylcyclohexane, 1,4-diamino-2-ethylcyclohexane, 1,4-diamino-2-isobutylcyclohexane, 1,4-diamino-2-n-butylcyclohexane, 1,4-diamino- Diamino-2-tert-butylcyclohexane, 1,3-diaminocyclobutane, 1,4-bis ( (Aminomethyl) cyclohexane, 1,3-bis (aminomethyl) cyclohexane, diaminobicycloheptane, diaminomethylbicycloheptane, diaminooxybicycloheptane, diaminomethyloxybicycloheptane, isophoronediamine, (Aminocyclohexyl) methane, bis (aminocyclohexyl) isopropylidene 6,6'-bis (3-aminophenoxy) -3,3,3 ' , 3'-tetramethyl-1,1'-spirobiindane, 6,6'- (4-aminophenoxy) -3,3,3 ', 3'-tetramethyl-1,1'-spirobiindane, and derivatives thereof, and they may be used singly or in combination. It may be used in combination.

The polyimide precursor of the present invention, A ₂ is in at least one type of a repeating unit represented by the above formula (1-2-1) will be represented by the formula (1-2-A), more preferably, A ₂ is the Wherein at least one kind of repeating unit represented by the formula (1-2-2) and / or A ₂ is represented by the formula (1-2-A) represented by the formula (1-2-A) 1-2-3) as a repeating unit. In other words, the diamine component giving the repeating unit of the above formula (1-2-1), more preferably the repeating unit of the above formula (1-2-2) and the above formula (1-2-3) ₂ contains a diamine component giving the structure of the above formula (1-2-A). The repeating unit represented by the formula (1-2-1), and more preferably the diamine component is the above formula (1-A to give the ₂ in the formula (1-2-2) and the formula (1-2-3) 2-A), the heat resistance of the obtained polyimide is improved.

The polyimide precursor of the present invention is a polyimide precursor having a structure represented by the formula (1-2-1), or a diamine component giving 100% by mole of A ₂ in the formula (1-2-2) and the formula (1-2-3) , The proportion of the diamine component giving the structure of the above formula (1-2-A) is preferably at least 50 mol%, more preferably at least 70 mol%, more preferably at least 80 mol% , More preferably 90 mol% or more, and particularly preferably 100 mol%. In other words, when A ₂ is a repeating unit represented by the formula (1-2-1) or the formula (1-2-2) and the formula (1-2-3) in which the structure of the formula (1-2-A) Of the total repeating units represented by the above formula (1-2-1), or the above-mentioned formulas (1-2-2) and (1-2-3) Is preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, still more preferably 90 mol% or more, particularly preferably 100 mol%. When the proportion of the diamine component giving the structure of the formula (1-2-A) is less than 50 mol%, the coefficient of linear thermal expansion of the obtained polyimide may become large. In one embodiment, from the viewpoint of the mechanical properties of the obtained polyimide, the above formula (1-2-1), or A ₂ in the above formula (1-2-2) and formula (1-2-3) The proportion of the diamine component giving the structure of the above formula (1-2-A) in the diamine component is preferably 80 mol% or less, more preferably 90 mol% or 90 mol% Mol% or less. (1-2-1), the above-mentioned formulas (1-2-2) and (1-2-), and other aromatic or aliphatic diamines such as 4,4'-oxydianiline, 3, preferably less than 20 mol%, more preferably less than 10 mol%, and more preferably less than 10 mol%, based on 100 mol% of the diamine component giving repeating units of the formula

In one embodiment, the polyimide precursor containing the repeating unit represented by the above formula (1-2-1) of the present invention is a polyimide precursor having the formula (1-2-A) wherein A ₂ is represented by the above formula (1-2-A) It is preferable that at least two repeating units of the repeating unit (2-1) are contained. In some embodiments, the polyimide precursor containing a repeating unit represented by the above formula (1-2-2), a repeating unit and / or the above formula (1-2-3) represented by the present invention, A ₂ is the It is preferable to contain at least two repeating units of the formula (1-2-2) or the formula (1-2-2) represented by the formula (1-2-A). In other words, the diamine component giving the repeating unit of the above formula (1-2-1) or the diamine component giving the repeating unit of the above formula (1-2-2) and the above formula (1-2-3) this, it is a preferred case containing at least two kinds of the diamine component to give the a ₂ is the chemical structure represented by the above formula (1-2-a). The diamine component to give the A ₂ in the formula (1-2-1) A _2, or the general formula (1-2-2) and the formula (1-2-3) in the formula (1-2- A), the balance between the high transparency and the low heat expansion property of the obtained polyimide can be obtained (i.e., the polyimide having a high transparency and a low thermal expansion coefficient can be obtained) .

The polyimide precursor of the present invention may contain at least two repeating units of the above formula (1-2-2) wherein A ₂ is the structure of the above formula (1-2-A), and A ₂ and it may be those containing at least two repeating units of the above formula (1-2-3) structure of the general formula (1-2-a), in addition, a ₂ is the formula (1-2-a) (1-2-2), wherein A ₂ is a repeating unit of the above formula (1-2-3) wherein the repeating unit of the above formula (1-2-2) is a structure of the above formula (1-2-A) It may contain one species.

In one embodiment, the polyimide precursor of the present invention is a polyimide precursor,

(i) A ₂ , m ₂ and / or n ₂ is 1 to 3, Z ₂ and / or W ₂ are each independently -NHCO-, -CONH-, -COO-, or -OCO- (1-2-1), which is the structure of any one of the above-mentioned formulas (1-2-A), preferably repeating units of the above formulas (1-2-2) and (1-2-3) (I), at least one compound

(ii) A ₂ is a structure of the above formula (1-2-A) wherein m ₂ and n ₂ are 0, or m ₂ and / or n ₂ is 1 to 3, and Z ₂ and W ₂ are (1-2-1), which is the structure of the above formula (1-2-A), preferably repeating units of the above formulas (1-2-2) and (1-2-3) II) is more preferable.

In this embodiment, examples of the repeating unit (I) include a repeating unit represented by the formula (1-2-1) wherein A ₂ is represented by any one of the following formulas (D-1) to (D- the repeating unit is preferable, and it is more preferably a repeating unit represented by the above formula (1-2-1) to represent any one of a ₂ to the formula (D-1) ~ (D -2). The diamine component giving the repeating unit of the above formula (1-2-1) wherein A ₂ is represented by the following formula (D-1) or (D-2) is 4,4'-diaminobenzene Anilide and the diamine component giving the repeating unit of the above formula (1-2-1) wherein A ₂ is represented by the following formula (D-3) is bis (4-aminophenyl) terephthalate, , Or may be used alone or in combination of a plurality of species.

(11)

In this embodiment, examples of the repeating unit (II) include a repeating unit represented by the formula (1-2-1) in which A ₂ is represented by any one of the following formulas (D-4) to (D- the repeating unit is preferable, and it is more preferably a repeating unit represented by the above formula (1-2-1) to represent any one of a ₂ to the formula (D-4) ~ (D -5). The diamine component giving the repeating unit of the above formula (1-2-1) wherein A ₂ is represented by the following formula (D-4) is p-phenylenediamine, and A ₂ is a group represented by the following formula (D-5 (D-6): wherein A < ₂ > is a group represented by the following formula (D-6) Is a m-tolidine. These diamines may be used alone or in combination of two or more.

[Chemical Formula 12]

In the polyimide precursor of this embodiment, the proportion of one or more of the repeating units (I) is 30 mol% or more and 70 mol% or less based on the total repeating units represented by the formula (1-2-1) , The proportion of one or more of the repeating units (II) is preferably from 30 mol% to 70 mol% of the total repeating units represented by the formula (1-2-1) The proportion of one or more kinds of the repeating units (II) is at least 40 mol% or more and 60 mol% or less among the total repeating units represented by the above formula (1-2-1) And particularly preferably from 40 mol% to 60 mol% of the total repeating units represented by the above general formula (1-2-1). In one embodiment, the proportion of the repeating unit (I) is preferably less than 60 mol%, more preferably 50 mol% or less, of the total repeating units represented by the formula (1-2-1) , And particularly preferably 40 mol% or less. It is noted that in one embodiment, the repeating units (I) and other than the repeating unit (II), contains a repeating unit (for example, represented by the other formula (1-2-1), A ₂ is a plurality of aromatic rings Of the total repeating units represented by the formula (1-2-1), and the aromatic rings are connected to each other through an ether bond (-O-), preferably less than 20% by mole, 10 mol% or less, particularly preferably 10 mol% or less. In one embodiment, the proportion of one or more of the repeating units (I) is 20 mol% or more and 80 mol% or less in total of the repeating units represented by the formula (1-2-1) It is preferable that the ratio of one or more kinds of the repeating units (II) is, in total, 20 mol% or more and 80 mol% or less among all the repeating units represented by the above formula (1-2-1).

In one embodiment, a polyimide precursor containing the repeating unit of the above formula (1-2-1), the above formula (1-2-2) and / or the above formula (1-2-3) is, formula (1-2-1), or the diamine component (the above formula (1-2-1) to give the a ₂ in the formula (1-2-2) and the formula (1-2-3) (1-2-2) and a repeating unit of the above formula (1-2-3)) is a repeating unit of the diamine component , And at least one of them is preferably 4,4'-diaminobenzanilide. The diamine component imparting A ₂ in the above formula (1-2-1), or the above formula (1-2-2) and the above formula (1-2-3) is a structure of the above formula (1-2-A) And one of them is 4,4'-diaminobenzanilide, a polyimide having both high transparency and low heat expansion ability as well as high heat resistance can be obtained.

In one embodiment, a polyimide precursor containing the repeating unit of the above formula (1-2-1), the above formula (1-2-2) and / or the above formula (1-2-3) is, formula (1-2-1), or the diamine component (the above formula (1-2-1) to give the a ₂ in the formula (1-2-2) and the formula (1-2-3) Bis (trifluoromethyl) benzidine and p-toluenesulfonic acid) as repeating units of formula (1-2-2) and repeating units of formula (1-2-3) At least one kind selected from phenylenediamine and 4,4'-diaminobenzanilide are particularly preferable. By combining these diamine components, a polyimide having high transparency, low heat expansion, and heat resistance is obtained.

In this embodiment, the above formula (1-2-1), or formula (1-2-2), and the diamine component to give the A ₂ in the formula (1-2-3) (Formula (1 2-1), or a diamine component which gives repeating units of the above formulas (1-2-2) and (1-2-3)), preferably 4,4'-diaminobenzene Anilide in an amount of 20 mol% or more and 80 mol% or less, and 20 mol% or more and 80 mol% or more in either one or both of p-phenylenediamine and 2,2'-bis (trifluoromethyl) % Or less, more preferably 30 mol% or more and 70 mol% or less of 4,4'-diaminobenzanilide, and further preferably contains p-phenylenediamine and 2,2'-bis (Trifluoromethyl) benzidine, and more preferably 30 mol% or more and 70 mol% or less, and particularly preferably 4,4'-diaminobenzene Anilide in an amount of 40 mol% or more and 60 mol% or less, and in an amount of 40 mol% or more and 60 mol% or more in either one or both of p-phenylenediamine and 2,2'-bis (trifluoromethyl) % Or less. As the diamine component to give the A ₂ in the formula (1-2-1), or formula (1-2-2) and the formula (1-2-3), the 4,4'-diamino-benzamide anilide And 30 mol% or more and 70 mol% or less in any one or both of p-phenylenediamine and 2,2'-bis (trifluoromethyl) benzidine, , Polyimide having high transparency, low heat expansion and heat resistance can be obtained. In some embodiments, formula (1-2-1), or formula (1-2-2), and the diamine component to give the A ₂ in the formula (1-2-3) (Formula (1 2-1), or a diamine component giving the repeating unit of the above formula (1-2-2) and the above formula (1-2-3), 4,4'-diaminobenzanilide is preferably used in an amount of 60 By mole, more preferably less than 50% by mole, particularly preferably 40% by mole or less.

The polyimide precursor of the present invention may contain other repeating units other than the repeating units represented by the above formula (1-2-1), or the repeating units represented by the above formulas (1-2-2) and (1-2-3) can do.

As the tetracarboxylic acid component for imparting other repeating units, other aromatic or aliphatic tetracarboxylic acids may be used. For example, 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane, 4- (2,5-dioxotetrahydrofuran-3-yl) Hydroxynaphthalene-1,2-dicarboxylic acid, pyromellitic acid, 3,3 ', 4,4'-benzophenonetetracarboxylic acid, 3,3', 4,4'-biphenyltetracarboxylic acid, (3,4-dicarboxyphenyl) sulfone dianhydride, m-terphenyl-3,4,3, 4,3'-biphenyltetracarboxylic acid, 4,4'-oxydiphthalic acid, ', 4'-tetracarboxylic acid dianhydride, p-terphenyl-3,4,3', 4'-tetracarboxylic acid dianhydride, biscarboxyphenyldimethylsilane, bisdicarboxyphenodydiphenylsulfide, sulfo 1,2,4-cyclobutanetetracarboxylic acid, isopropylidene diphenoxy bisphthalic acid, cyclohexane-1,2,4,5-tetracarboxylic acid, [1,1'-bis (Cyclohexane)] -3,3 ', 4,4'-tetracarboxylic acid, [1,1'-non (cyclohexane)] - 2,3,3' 1,1'-bis (cyclohexane)] - 2,2 ', 3,3'-te (Cyclohexane-1,2-dicarboxylic acid), 4,4'- (propane-2,2-diyl) bis (cyclohexane-1,2-dicarboxylic acid (Cyclohexane-1,2-dicarboxylic acid), 4,4'-thiobis (cyclohexane-1,2-dicarboxylic acid), 4,4'-oxybis (Cyclohexane-1,2-dicarboxylic acid), 4,4'- (dimethylsilanediyl) bis (cyclohexane-1,2-dicarboxylic acid), 4,4'- (Tetrafluoropropane-2,2-diyl) bis (cyclohexane-1,2-dicarboxylic acid), octahydropentalene-1,3,4,6-tetracarboxylic acid, bicyclo [2.2. Heptane-2,3,5-tricarboxylic acid, bicyclo [2.2.2] heptane-2,3,5,6-tetracarboxylic acid, 6- (carboxymethyl) bicyclo [ Octane-2,3,5,6-tetracarboxylic acid, bicyclo [2.2.2] octa-5-ene-2,3,7,8-tetracarboxylic acid, tricyclo [4.2.2.02,5] Decane-3,4,7,8-tetracarboxylic acid, tricyclo [4.2.2.02,5] deca-7-ene-3,4,9,10-tetracarboxylic acid , 9-oxatricyclo [4.2.1.02,5] nonane-3,4,7,8-tetracarboxylic acid, (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene- Derivatives such as 2c, 3c, 6c, 7c-tetracarboxylic acid, (4arH, 8acH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2t, 3t, 6c, 7c-tetracarboxylic acid , And acid anhydrides thereof. These acid anhydrides may be used singly or in combination. Of these, bicyclo [2.2.1] heptane-2,3,5,6-tetracarboxylic acid, bicyclo [2.2.2] octane-2,3,5,6-tetracarboxylic acid, (4arH , 8cH) -decahydro-1t, 4t: 5c, 8c-dimethanonaphthalene-2c, 3c, 6c, 7c-tetracarboxylic acid, (4arH, 8acH) Derivatives such as dimethanonaphthalene-2t, 3t, 6c, 7c-tetracarboxylic acid and the like, and acid dianhydrides thereof are more preferable because of easy production of polyimide and excellent heat resistance of the obtained polyimide. These acid dianhydrides may be used singly or in combination of plural kinds.

In the case of the polyimide precursor containing the repeating unit represented by the above formula (1-2-2) and / or the above formula (1-2-3), the tetracarboxylic acid component giving another repeating unit may be cis-endo spiro-a-cyclopentanone-a'-spiro-2 " -norbornane-5,5 ", 6,6 " -tetracarboxylic acids, etc., and trans -endo-endo-norbornane-2-spiro- [alpha] -cyclopentanone- [alpha] ' -spiro-2 " -norbornane-5,5 ", 6,6 " -tetracarboxylic acids Spiro-? -Cyclopentanone-? '- spiro-2 "-norbornane-5,5", 6,6 "-tetracarboxylic acids and the like (for example, For example, a solution of 4,4'-bis (2-spiro-a-cyclopentanone-a'-spiro-2 '' -norbornane-5,5 ", 6,6 "- tetracarboxylic acid dianhydride) Type stereoisomers may be used.

The diamine component giving another repeating unit may be a diamine component giving the structure of the above formula (1-2-A). In other words, the diamine component giving another repeating unit may be a repeating unit of the above formula (1-2-1) wherein A ₂ is a structure of the above formula (1-2-A), or A ₂ is a repeating unit of the above formula (1- The diamine exemplified as the diamine component giving the repeating unit of the above formula (1-2-2) and the above formula (1-2-3) which is the structure of the formula (2-A) can be used. These diamines may be used singly or in combination of plural kinds.

As the diamine component giving another repeating unit, other aromatic or aliphatic diamines can be used. (4-aminophenyl) sulfide, p-methylenebis (phenylenediamine), p-methylenebis (phenylenediamine) Benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, 2,2- Bis (4-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, bis (Phenyl) propane, 2,2-bis (3-amino-4-hydroxyphenyl) hexafluoropropane, bis 3,3'-dimethoxy-4,4'-diaminobiphenyl, 3,3'-dichloro-4,4'-diaminobiphenyl, 3,3'-dimethoxy- 4,4'-diaminobiphenyl, 9,9-bis (4-aminophenyl) fluorene, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'- '-Bis (3-aminophenoxy) biphenyl, 1,4-diamino-cyclo Di-2-ethylcyclohexane, 1,4-diamino-2-n-propylcyclohexane, 1,4-diamino-2-methylcyclohexane, 2-isopropylcyclohexane, 1,4-diamino-2-n-butylcyclohexane, 1,4-diamino-2-isobutylcyclohexane, 1,2-diaminocyclohexane, 1,3-diaminocyclobutane, 1,4-bis (aminomethyl) cyclohexane, 1,3-diamino- - bis (aminomethyl) cyclohexane, diaminobicycloheptane, diaminomethylbicycloheptane, diaminooxybicycloheptane, diaminomethyloxybicycloheptane, isophoronediamine, diaminotricyclodecane, diaminomethyl (Aminocyclohexyl) methane, bis (aminocyclohexyl) isopropylidene 6,6'-bis (3-aminophenoxy) -3,3,3 ', 3'-tetramethyl- 1'-spirobiindane, 6,6'-bis (4-aminophenoxy) -3,3,3 ', 3'-tetramethyl-1,1'-spirobiindane, and derivatives thereof, and they may be used alone or in combination of plural species.

The synthesis method of norbornane-2-spiro- [alpha] -cyclopentanone- [alpha] ' -spiro-2 " -norbornane-5,5 ", 6,6 " -tetracarboxylic acids, , But it can be synthesized by the method described in Patent Document 11 and the like. As described in Non-Patent Document 3, depending on the synthesis method, various kinds of stereoisomers may be contained. Spiro-? -Cyclopentanone-? '- spiro-2 "-norbornane-5,5", 6,6 "-tetracarboxylic acids, or the like, or an intermediate thereof Column or the like, the stereoisomer can be used alone or in the form of a mixture of various species.

trans-endo-endo-norbornane-2-spiro- [alpha] -cyclopentanone- [alpha] ' -spiro-2 " -norbornane-5,5 ", 6,6 " -tetracarboxylic acids , And cis-endo-endo-norbornane-2-spiro- [alpha] -cyclopentanone-a'-spiro-2 " -norbornane-5,5 ", 6,6 & Spiro-? -Cyclopentanone? '- spiro-2' '- norbornane-5,5' ', 6,6' '- spiro- -Tetracarboxylic acids, and the like, or an intermediate thereof by a column or the like.

When the tetracarboxylic acid component and the diamine component contain an isomer, the isomer may be isolated and used for polymerization or the isomer may be used as a mixture for polymerization or the like.

In the polyimide precursor of the present invention, R ₁ and R ₂ in the formula (1), R ₃ and R ₄ in the formula (2) and R ₅ and R ₆ in the formula (3) An alkyl group having 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms. R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ can change the kind of the functional group and the introduction ratio of the functional group by a production method described below.

When R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ are hydrogen, production of polyimide tends to be easy.

When R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ are an alkyl group having 1 to 6 carbon atoms, preferably 1 to 3 carbon atoms, the storage stability of the polyimide precursor tends to be excellent. In this case, it is more preferable that R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ are a methyl group or an ethyl group.

When R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ are alkylsilyl groups having 3 to 9 carbon atoms, solubility of the polyimide precursor tends to be excellent. In this case, it is more preferable that R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ are a trimethylsilyl group or a t-butyldimethylsilyl group.

R ₁ and R ₂ , R ₃ and R ₄ , and R ₅ and R ₆ are each at least 25%, preferably at least 50%, more preferably at least 50%, when the alkyl group or the alkylsilyl group is introduced, although the introduction ratio of the functional group is not particularly limited. , And more preferably 75% or more, can be an alkyl group or an alkylsilyl group.

The polyimide precursor of the present invention, R ₁ and R _2, R ₃ and R _4, R ₅ and R ₆ is by taking the chemical structure, 1) a polyamic acid (R ₁ and R _2, R ₃ and R _4, R ₅ and R ₆ are hydrogen), 2) a polyamide acid ester (at least a part of R ₁ and R ₂ , R ₃ and R ₄ , R ₅ and R ₆ are alkyl groups), 3) 4) polyamide acid silyl ester R _1, and R ₂ , R _3, and R ₄ , R _5, and R ₆ is an alkylsilyl group). The polyimide precursor of the present invention can be easily produced by the following production method for each classification. However, the method for producing the polyimide precursor of the present invention is not limited to the following production method.

1) Polyamic acid

The polyimide precursor of the present invention is a polyimide precursor having a molar ratio of the tetracarboxylic acid dianhydride and the diamine component as the tetracarboxylic acid component in the solvent to the diamine component relative to the tetracarboxylic acid component [mol of the diamine component / tetra The molar number of the carboxylic acid component] of the polyimide precursor solution composition is preferably from 0.90 to 1.10, more preferably from 0.95 to 1.05, for example, while suppressing imidization at a relatively low temperature of 120 DEG C or less, .

More specifically, the diamine is dissolved in an organic solvent, the tetracarboxylic acid dianhydride is gradually added while stirring the solution, and the solution is stirred at a temperature of 0 to 120 ° C, preferably 5 to 80 ° C By stirring for 1 to 72 hours, a polyimide precursor is obtained. When the reaction is carried out at 80 占 폚 or higher, there is a possibility that the polyimide precursor can not be stably produced because the molecular weight varies depending on the temperature history at the time of polymerization and the imidization proceeds by heat. The order of addition of the diamine and the tetracarboxylic acid dianhydride in the above production method is preferable because the molecular weight of the polyimide precursor tends to rise. In addition, the order of addition of the diamine and the tetracarboxylic acid dianhydride in the above-described production method can be reversed, and the precipitate is preferably reduced.

When the molar ratio of the tetracarboxylic acid component to the diamine component is excessive, a carboxylic acid derivative in an amount substantially equivalent to the excess moles of the diamine component is added, if necessary, and the tetracarboxylic acid component and the diamine component Can be approximated to approximately equivalent. Examples of the carboxylic acid derivative herein include a tetracarboxylic acid which does not substantially increase the viscosity of the polyimide precursor solution, that is substantially not involved in molecular chain extension, or a tricarboxylic acid which functions as a terminal terminator and anhydrides thereof, Dicarboxylic acid and its anhydride are preferable.

2) Polyamide acid ester

The tetracarboxylic acid dianhydride is reacted with an arbitrary alcohol to obtain a diester dicarboxylic acid and then reacted with a chlorinating reagent (thionyl chloride, oxalyl chloride, etc.) to obtain diester dicarboxylic acid chloride. The polyimide precursor is obtained by stirring the diester dicarboxylic acid chloride and the diamine at a temperature of -20 to 120 ° C, preferably -5 to 80 ° C for 1 to 72 hours. When the reaction is carried out at 80 占 폚 or higher, there is a possibility that the polyimide precursor can not be stably produced because the molecular weight varies depending on the temperature history at the time of polymerization and the imidization proceeds by heat. Also, a polyimide precursor can be easily obtained by dehydrating and condensing a diester dicarboxylic acid and a diamine using a phosphorus-containing condensing agent, a carbodiimide condensing agent or the like.

Since the polyimide precursor obtained by this method is stable, it is also possible to carry out refining such as re-precipitation by adding a solvent such as water or alcohol.

3) Polyamidic acid silyl ester (indirect method)

A silylating agent is reacted with a diamine in advance to obtain a silylated diamine. If necessary, the silylated diamine is purified by distillation or the like. Then, the silylated diamine is dissolved in the dehydrated solvent, the tetracarboxylic acid dianhydride is gradually added while stirring, and the mixture is stirred at 0 to 120 ° C, preferably 5 to 80 ° C for 1 to 72 hours , A polyimide precursor is obtained. When the reaction is carried out at 80 占 폚 or higher, there is a possibility that the polyimide precursor can not be stably produced because the molecular weight varies depending on the temperature history at the time of polymerization and the imidization proceeds by heat.

As the silylating agent used herein, the use of a silylating agent containing no chlorine is preferable because it is not necessary to purify the silylated diamine. Examples of the silylating agent containing no chlorine atom include N, O-bis (trimethylsilyl) trifluoroacetamide, N, O-bis (trimethylsilyl) acetamide and hexamethyldisilazane. Particularly preferred are N, O-bis (trimethylsilyl) acetamide and hexamethyldisilazane in that they do not contain fluorine atoms and are inexpensive.

An amine catalyst such as pyridine, piperidine or triethylamine can be used for the silylation reaction of the diamine in order to accelerate the reaction. This catalyst can be used as it is as a polymerization catalyst for the polyimide precursor.

4) Polyamide acid silyl ester (direct method)

The polyamic acid solution obtained by the method 1) and the silylating agent are mixed and stirred at 0 to 120 ° C, preferably 5 to 80 ° C for 1 to 72 hours to obtain a polyimide precursor. When the reaction is carried out at 80 占 폚 or higher, there is a possibility that the polyimide precursor can not be stably produced because the molecular weight varies depending on the temperature history at the time of polymerization and the imidization proceeds by heat.

As the silylating agent used herein, the use of a silylating agent containing no chlorine is preferable because it is not necessary to purify the silylated polyamic acid or the obtained polyimide. Examples of the silylating agent containing no chlorine atom include N, O-bis (trimethylsilyl) trifluoroacetamide, N, O-bis (trimethylsilyl) acetamide and hexamethyldisilazane. Particularly preferred are N, O-bis (trimethylsilyl) acetamide and hexamethyldisilazane in that they do not contain fluorine atoms and are inexpensive.

Since the above production method can be preferably carried out in an organic solvent, as a result, a solution or a solution composition containing the polyimide precursor can be easily obtained.

Examples of the solvent to be used for preparing the polyimide precursor include N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, N, N-dimethylacetamide is particularly preferable. However, when the raw material monomer component and the resulting polyimide precursor are dissolved, any kind of solvent can be used without any problem So that the structure is not particularly limited. Examples of the solvent include amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methylpyrrolidone,? -Butyrolactone,? -Valerolactone,? -Valerolactone, Cyclic ester solvents such as lactone, -caprolactone and -methyl- -butyrolactone, carbonate solvents such as ethylene carbonate and propylene carbonate, glycol solvents such as triethylene glycol, m-cresol, p-cresol, Phenol-based solvents such as 3-chlorophenol and 4-chlorophenol, acetophenone, 1,3-dimethyl-2-imidazolidinone, sulfolane, dimethylsulfoxide and the like are preferably employed. It is also possible to use other common organic solvents such as phenol, o-cresol, butyl acetate, ethyl acetate, isobutyl acetate, propylene glycol methyl acetate, ethyl cellosolve, butyl cellosolve, But are not limited to, benzoic acid, benzoic acid, benzoic acid, benzoic acid, benzoic acid, benzoic acid, benzoic acid, isophthalic acid, Methyl ethyl ketone, acetone, butanol, ethanol, xylene, toluene, chlorbenzene, terpene, mineral spirits, and petroleum naphtha type solvents. Further, a plurality of kinds of solvents may be used in combination.

In the present invention, the logarithmic viscosity of the polyimide precursor is not particularly limited, but the logarithmic viscosity in the N, N-dimethylacetamide solution at a concentration of 0.5 g / dl at 30 캜 is preferably 0.2 dl / g or more, Is preferably 0.3 dl / g or more, particularly preferably 0.4 dl / g or more. When the logarithmic viscosity is 0.2 dl / g or more, the molecular weight of the polyimide precursor is high, and the obtained polyimide has excellent mechanical strength and heat resistance.

The polyimide precursor composition of the present invention contains a polyimide precursor and a phosphorus compound, and can be prepared by adding a phosphorus compound to a polyimide precursor solution or solution composition obtained by the above production method. If necessary, the solvent may be removed or added, or a desired component other than the phosphorus compound may be added. In addition, the tetracarboxylic acid component (tetracarboxylic acid dianhydride, etc.), the diamine component and the phosphorus compound are added to the solvent, and the tetracarboxylic acid component and the diamine component are reacted in the presence of the phosphorus compound, (A solution composition containing a polyimide precursor and a phosphorus compound) may be obtained.

The phosphorus compound used in the present invention contains a phosphorus atom and has a boiling point lower than the decomposition temperature at 1 atm and 350 ° C or lower, preferably 300 ° C or lower, more preferably lower than 250 ° C Preferably 210 DEG C or less, particularly preferably 200 DEG C or less. The boiling point at 1 atm is lower than the decomposition temperature and is 350 ° C or lower, preferably 300 ° C or lower, more preferably 250 ° C or lower, even more preferably 210 ° C or lower, particularly preferably 200 ° C or lower By adding the compound, polyimide having higher heat resistance can be obtained while maintaining high transparency.

The phosphorus compound used in the present invention is not particularly limited as long as the boiling point at 1 atm is lower than the decomposition temperature and is 350 ° C or lower. However, it is preferable that the phosphorus compound has a PO bond and trimethyl phosphate (boiling point (197 占 폚), trimethyl phosphite (boiling point at 1 atm: 111.5 占 폚), dimethyl phosphite (boiling point at 1 atm: 171 占 폚), diethyl azine (boiling point at 1 atm: 188 占 폚) Do. The phosphorus compound may be used singly or in combination of plural kinds.

In the present invention, the content of the phosphorus compound in the polyimide precursor composition is not particularly limited, but is preferably 0.01 mole or more, more preferably 0.03 mole or more, and more preferably 0.05 mole or more per mole of the repeating unit of the polyimide precursor And still more preferably 0.1 mol or more. The upper limit of the content of the phosphorus compound in the polyimide precursor composition is not particularly limited, but is usually 8 moles or less, preferably 6 moles or less, and further preferably 5 moles or less per mole of the repeating unit of the polyimide precursor And particularly preferably less than 5 moles. When the content of the phosphorus compound is too large, the heat resistance or transparency of the obtained polyimide may be lowered. Here, 1 mole of the repeating unit of the polyimide precursor corresponds to 1 mole of the tetracarboxylic acid component.

The polyimide precursor composition of the present invention usually contains a solvent. As the solvent used in the polyimide precursor composition of the present invention, there is no problem when the polyimide precursor is dissolved, and the structure thereof is not particularly limited. Examples of the solvent include amide solvents such as N, N-dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone,? -Butyrolactone,? -Valerolactone, a cyclic ester solvent such as? -caprolactone,? -caprolactone and? -methyl-? -butyrolactone, a carbonate solvent such as ethylene carbonate and propylene carbonate, a glycol solvent such as triethylene glycol, m-cresol, p Phenol-based solvents such as cresol, 3-chlorophenol and 4-chlorophenol, acetophenone, 1,3-dimethyl-2-imidazolidinone, sulfolane, dimethylsulfoxide and the like are preferably employed. It is also possible to use other common organic solvents such as phenol, o-cresol, butyl acetate, ethyl acetate, isobutyl acetate, propylene glycol methyl acetate, ethyl cellosolve, butyl cellosolve, But are not limited to, benzoic acid, benzoic acid, benzoic acid, benzoic acid, benzoic acid, benzoic acid, benzoic acid, isophthalic acid, Methyl ethyl ketone, acetone, butanol, ethanol, xylene, toluene, chlorbenzene, terpene, mineral spirits, and petroleum naphtha type solvents. A plurality of these may be used in combination. As the solvent of the polyimide precursor composition, the solvent used in preparing the polyimide precursor may be used as it is.

In the present invention, the total amount of the tetracarboxylic acid component and the diamine component is at least 5% by mass, preferably at least 10% by mass, more preferably at least 15% by mass, based on the total amount of the solvent, the tetracarboxylic acid component and the diamine component By mass or more. In general, the total amount of the tetracarboxylic acid component and the diamine component is preferably 60 mass% or less, more preferably 50 mass% or less, based on the total amount of the solvent, the tetracarboxylic acid component, and the diamine component. This concentration is a concentration that approximates to the solid content concentration originating from the polyimide precursor. However, when the concentration is too low, it is difficult to control the film thickness of the polyimide film obtained when the polyimide film is produced, for example have.

In the present invention, the viscosity (rotational viscosity) of the polyimide precursor composition is not particularly limited, but a rotational viscosity measured at a temperature of 25 DEG C and a shear rate of 20 sec < ^-1 > Pa · sec is preferable, and 0.1 to 100 Pa · sec is more preferable. If necessary, a tin-plasticity may be imparted. When the viscosity is within the above-mentioned range, it is easy to handle, and the film is suppressed from being cratered and the leveling property is excellent when coating or film formation is carried out.

The polyimide precursor composition of the present invention may contain, if necessary, a chemical imidization agent (an acid anhydride such as acetic anhydride, an amine compound such as pyridine or isoquinoline), an antioxidant, a filler (inorganic particles such as silica) , A coupling agent such as a pigment and a silane coupling agent, a primer, a flame retardant, a defoaming agent, a leveling agent, a rheology control agent (flow aid), a release agent and the like.

The polyimide of the present invention can be obtained by imidizing the polyimide precursor composition of the present invention as described above (i.e., dehydrating and cyclizing the polyimide precursor). The method of imidization is not particularly limited, and a known method of heat imidization or chemical imidization can be suitably applied. The form of the obtained polyimide is preferably a film, a laminate of a polyimide film and another substrate, a coating film, a powder, a bead, a molded article, a foam, and the like.

In the present invention, the polyimide precursor composition can be heat-treated to imidize the polyimide precursor. The maximum heating temperature for the heat treatment for imidation is not particularly limited, but is usually 200 ° C or higher, preferably 350 ° C or higher, more preferably 380 ° C or higher, and more preferably 400 ° C or higher Particularly preferred. By setting the maximum heating temperature of the heat treatment for imidization to a temperature higher than 350 ° C, more preferably higher than 380 ° C, particularly preferably higher than 400 ° C, the mechanical properties of the obtained polyimide . The upper limit of the maximum heating temperature in the heat treatment is not particularly limited, but is preferably 500 ° C or lower.

For example, the polyimide precursor composition of the present invention is applied on a substrate in a flexible manner, and the polyimide precursor composition on the substrate is heat-treated at a temperature of not less than 200 占 폚, more preferably not less than 350 占 폚, By imidizing the polyimide precursor, the polyimide can be preferably produced. The heating profile is not particularly limited and can be appropriately selected. However, from the viewpoint of productivity, it is preferable that the heating treatment time is short.

The polyimide precursor composition of the present invention is coated on the substrate in a softened state, preferably at a temperature of 180 ° C or lower, to form a film of the polyimide precursor composition on the substrate, It is preferable to heat the polyimide precursor by heat treatment at a temperature of not less than 200 占 폚 at the maximum heating temperature, more preferably not more than 350 占 폚 in the state where the end portion of the film is peeled off from the substrate, .

An example of a more specific process for producing the polyimide (polyimide film / substrate laminate or polyimide film) of the present invention will be described later.

The polyimide (polyimide of the present invention) obtained from the polyimide precursor composition of the present invention is not particularly limited, but it has a coefficient of linear thermal expansion of 150 to 250 DEG C, preferably 65 ppm / K or less , More preferably not more than 50 ppm / K, still more preferably not more than 35 ppm / K, still more preferably not more than 30 ppm / K, particularly preferably not more than 20 ppm / K. When the coefficient of linear thermal expansion is large, a difference in coefficient of linear thermal expansion from a conductor such as a metal is large, and there arises a problem that warpage increases when a circuit board is formed.

The polyimide (polyimide of the present invention) obtained from the polyimide precursor composition of the present invention is not particularly limited, but it is preferable that the total light transmittance (average light transmittance at a wavelength of 380 nm to 780 nm) , It may be 87% or more, and more preferably 88% or more. When it is used for a display purpose or the like, if the total light transmittance is low, it is necessary to make the light source strong, which may cause energy consumption.

Particularly, when a polyimide film such as a display purpose is used for the purpose of transmitting light, the polyimide film preferably has high transparency. The polyimide (polyimide of the present invention) obtained from the polyimide precursor composition of the present invention is not particularly limited, but preferably has a light transmittance at a wavelength of 400 nm in a film having a thickness of 10 占 퐉, preferably at least 75% , Preferably at least 78%, more preferably at least 80%, particularly preferably at least 80%.

The film made of the polyimide (polyimide of the present invention) obtained from the polyimide precursor composition of the present invention may differ depending on the application, but the thickness of the film is preferably 0.1 to 250 占 퐉, 1 mu m to 150 mu m, more preferably 1 mu m to 50 mu m, and particularly preferably 1 mu m to 30 mu m. When the polyimide film is used for the purpose of transmitting light, when the polyimide film is too thick, the light transmittance may be lowered.

The polyimide (the polyimide of the present invention) obtained from the polyimide precursor composition of the present invention is not particularly limited, but a 1% weight reduction temperature which is an index of the heat resistance of the polyimide film is preferably 440 캜 or higher, May be 450 DEG C or higher, more preferably 480 DEG C or higher, and particularly preferably 485 DEG C or higher. When a gas barrier film or the like is formed on a polyimide by forming a transistor on the polyimide or the like, if the heat resistance is low, swelling occurs due to the outgass accompanying the decomposition of the polyimide between the polyimide and the barrier film There is a case.

The polyimide obtained from the polyimide precursor composition of the present invention, that is, the polyimide of the present invention has excellent properties such as high transparency, folding resistance and high heat resistance, and further has a very low coefficient of linear thermal expansion, It can be suitably used for a substrate, a transparent substrate for a touch panel, or a substrate for a solar cell.

Hereinafter, an example of a method for producing a polyimide film / substrate laminate or a polyimide film using the polyimide precursor composition of the present invention will be described. However, the present invention is not limited to the following method.

The polyimide precursor composition (varnish) of the present invention is softened and applied to a substrate such as a ceramic (glass, silicon, alumina, etc.), metal (copper, aluminum, stainless steel, etc.), heat resistant plastic film (polyimide film, , In a vacuum, in an inert gas such as nitrogen, or in air, using hot air or infrared rays, at a temperature of 20 to 180 ° C, preferably 20 to 150 ° C. Next, the obtained polyimide precursor film is peeled off from the base material, or the polyimide precursor film is peeled off from the base material, hot air or infrared rays are irradiated in an inert gas such as nitrogen, , The polyimide film / base laminate or the polyimide film can be produced by heat-imidization at a temperature of, for example, 200 to 500 ° C, preferably a maximum heating temperature of 350 ° C or more. Further, in order to prevent oxidization deterioration of the obtained polyimide film, the heat imidization is preferably carried out in vacuum or in an inert gas. The thickness of the polyimide film (polyimide film layer in the case of the polyimide film / substrate laminate) herein is preferably 1 to 250 占 퐉, more preferably 1 to 150 占 퐉, Mu m.

The imidization reaction of the polyimide precursor can be carried out in the same manner as in the case of the polyimide precursor in the presence of a tertiary amine such as pyridine or triethylamine in the presence of a dehydrating cyclization reagent such as acetic anhydride Or by chemical treatment such as immersion in a solution containing a surfactant. In addition, these dehydrating and cyclization reagents may be added and stirred in advance in a polyimide precursor composition (varnish), and the mixture may be plied and dried on a substrate to partially imidize the polyimide precursor. , A polyimide film / base laminate or a polyimide film can be obtained.

A flexible conductive substrate can be obtained by forming a conductive layer on one side or both sides of the polyimide film / substrate laminate or polyimide film thus obtained.

The flexible conductive substrate can be obtained, for example, by the following method. That is, as a first method, a polyimide film / base layered product is formed on the surface of the polyimide film by sputtering, vapor deposition, printing, or the like without peeling the polyimide film from the base material and a conductive material (metal or metal oxide, , Conductive carbon, or the like) is formed to prepare a conductive laminate of a conductive layer / polyimide film / substrate. Thereafter, if necessary, the conductive layer / polyimide film laminate is peeled off from the substrate to obtain a transparent and flexible conductive substrate comprising the conductive layer / polyimide film laminate.

As a second method, a polyimide film is peeled from a substrate of a polyimide film / substrate laminate to obtain a polyimide film, and a conductive material (metal or metal oxide, conductive organic material, conductive carbon, etc.) Can be formed in the same manner as in the first method to obtain a transparent and flexible conductive substrate made of the conductive layer / polyimide film laminate and the conductive layer / polyimide film laminate / conductive layer.

In addition, in the first and second methods, a gas barrier layer such as water vapor or oxygen, a light-shielding layer such as oxygen, or the like may be formed by sputtering, vapor deposition or gel-sol method before forming the conductive layer on the surface of the polyimide film, Or the like may be formed.

The conductive layer is preferably formed by a method such as a photolithography method, various printing methods, and an inkjet method.

The substrate of the present invention thus obtained has a circuit of a conductive layer on the surface of a polyimide film constituted by the polyimide of the present invention, optionally with a gas barrier layer or an inorganic layer interposed therebetween. This substrate is flexible, has excellent transparency, bending property, heat resistance, further has a very low coefficient of linear thermal expansion and excellent solvent resistance, so that it is easy to form a fine circuit. Therefore, this substrate can be preferably used as a substrate for a display, a touch panel, or a solar cell.

That is, a transistor (an inorganic transistor or an organic transistor) is further formed on the substrate by vapor deposition, various printing methods, ink jetting or the like to produce a flexible thin film transistor, and a liquid crystal element, And is preferably used as a photoelectric element.

Example

Hereinafter, the present invention will be further described with reference to examples and comparative examples. The present invention is not limited to the following examples.

In each of the following examples, evaluation was carried out in the following manner.

≪ Evaluation of polyimide film &

[400 nm light transmittance, total light transmittance]

(Light transmittance at 380 nm to 780 nm) of the polyimide film having a thickness of about 10 mu m at 400 nm was measured using an ultraviolet visible spectrophotometer / V-650DS (manufactured by Nippon Shokubai Co., Ltd.) . The light transmittance at 400 nm and the total light transmittance were calculated using a Lambert-Beer equation with a reflectance of 10% and a total light transmittance at 400 nm measured. The calculation formula is shown below.

Log ₁₀ ((T ₁ + 10) / 100) = 10 / L (Log ₁₀ ((T ₁ '+ 10) / 100)

Log ₁₀ ((T ₂ + 10) / 100) = 10 / L (Log ₁₀ ((T ₂ '+ 10) / 100)

T ₁ : light transmittance (%) at 400 nm of a 10 탆 thick polyimide film with a reflectance of 10%

T ₁ ': light transmittance (%) at 400 nm measured

T ₂ : total light transmittance (%) of a polyimide film of 10 탆 thickness with a reflectance of 10%

T ₂ ': Total light transmittance (%) measured

L: film thickness of measured polyimide film (mu m)

[Modulus of elasticity, elongation at break]

A polyimide film having a film thickness of about 10 탆 was struck in a dumbbell shape conforming to IEC 450 standard and used as a test piece. Tensilon manufactured by ORIENTEC Co., Ltd. was used to measure the initial modulus of elasticity and elongation at break at a chuck length of 30 mm and a tensile rate of 2 mm / .

[Linear Thermal Expansion Coefficient (CTE)]

A polyimide film having a film thickness of about 10 탆 was cut into a short strip of 4 mm in width and used as a test piece and a test piece of 15 mm in length between chucks and 2 g in weight was prepared using TMA / SS6100 (manufactured by SII Ai Nanotechnology Co., Ltd.) , And the temperature was raised to 500 ° C at a heating rate of 20 ° C / min. From the obtained TMA curve, the coefficient of linear thermal expansion from 150 deg. C to 250 deg. C was obtained.

[1% weight reduction temperature]

Using a polyimide film having a film thickness of about 10 占 퐉 as a test piece, the temperature was raised from 25 占 폚 to 600 占 폚 at a heating rate of 10 占 폚 / min in a nitrogen stream using a calorimeter apparatus (Q5000IR) manufactured by TA Instruments. From the weight curve obtained, a 1% weight reduction temperature was determined.

The abbreviations, purity and the like of the raw materials used in the following examples are as follows.

[Diamine component]

DABAN: 4,4'-diaminobenzanilide [Purity: 99.90% (GC analysis)]

PPD: p-phenylenediamine [purity: 99.9% (GC analysis)]

TFMB: 2,2'-bis (trifluoromethyl) benzidine [Purity: 99.83% (GC analysis)]

4,4'-ODA: 4,4'-oxydianiline [Purity: 99.9% (GC analysis)]

BAPB: 4,4'-bis (4-aminophenoxy) biphenyl [purity: 99.93% (HPLC analysis)]

[Component of tetracarboxylic acid]

s-BPDA: 3,3 ', 4,4'-biphenyltetracarboxylic acid dianhydride [purity 99.9% (1 H-NMR analysis)]

6FDA: 4,4 '- (2,2-hexafluoroisopropylene) diphthalic acid dianhydride [purity 99.77% (1 H-NMR analysis)]

PMDA-HS: 1R, 2S, 4S, 5R-Cyclohexanetetracarboxylic acid dianhydride [Purity: 99.9% (GC analysis)]

CpODA-tee: trans-endo-endo-norbornane-2-spiro- [alpha] -cyclopentanone-a'- spiro-2 " -norbornane-5,5 ", 6,6 & Carboxylic acid dianhydride

CpODA-cee: cis-endo-endo-norbornane-2-spiro- [alpha] -cyclopentanone-a'- spiro-2 " -norbornane-5,5 ", 6,6 & Carboxylic acid dianhydride

CpODA: a mixture of CpODA-tee and CpODA-cee

[Table 1]

[menstruum]

NMP: N-methyl-2-pyrrolidone

Table 1-1 shows the tetracarboxylic acid components used in Examples and Comparative Examples, Table 1-2 shows the diamine components used in Examples and Comparative Examples, and Table 1-3 shows the structural formulas of the phosphorus compounds used in Examples and Comparative Examples. .

[Table 1-1]

[Table 1-2]

[Table 1-3]

[Synthesis Example 1]

90.91 g (0.40 mol) of DABAN and 64.88 g (0.60 mol) of PPD were placed in a reactor purged with nitrogen gas and N-methyl-2-pyrrolidone was added to the reactor under the conditions of the total mass of the injected monomers 2835.90 g as a total amount of 16% by mass) was added to the mixture, followed by stirring at room temperature for 1 hour. 384.38 g (1.00 moles) of CpODA was gradually added to this solution. Followed by stirring at room temperature for 12 hours to obtain a homogeneous and viscous polyimide precursor solution (varnish A).

[Synthesis Example 2]

90.91 g (0.40 mol) of DABAN, 54.07 g (0.50 mol) of PPD and 36.84 g (0.10 mol) of BAPB were placed in a reaction vessel substituted with nitrogen gas and N-methyl-2-pyrrolidone was added to the total monomer 2972.56 g which is a total amount of the diamine component and the carboxylic acid component) of 16% by mass was added and the mixture was stirred at room temperature for 1 hour. 384.38 g (1.00 moles) of CpODA was gradually added to this solution. Followed by stirring at room temperature for 12 hours to obtain a uniform and viscous polyimide precursor solution (varnish B).

[Synthesis Example 3]

20.02 g (0.10 mol) of 4,4'-ODA was placed in a reaction vessel purged with nitrogen gas, and N-methyl-2-pyrrolidone was added to the reactor so that the total mass of the injected monomers (total of diamine component and carboxylic acid component) 207.21 g, which was a content of 17% by mass, was added, and the mixture was stirred at room temperature for 1 hour. To this solution was slowly added 22.41 g (0.10 mmol) of PMDA-HS. Followed by stirring at room temperature for 12 hours to obtain a homogeneous and viscous polyimide precursor solution (varnish C).

[Synthesis Example 4]

32.02 g (0.10 mmol) of TFMB was placed in a reaction vessel purged with nitrogen gas, and N-methyl-2-pyrrolidone was added to the reaction vessel in such a manner that the total mass of the injected monomers (total of diamine component and carboxylic acid component) 287.79 g was added thereto, followed by stirring at room temperature for 1 hour. 8.83 g (0.03 mol) of s-BPDA and 31.10 g (0.07 mol) of 6FDA were gradually added to this solution. Followed by stirring at room temperature for 12 hours to obtain a homogeneous and viscous polyimide precursor solution (varnish D).

[Example 1]

0.07 g (0.50 mmol) of trimethyl phosphate and 0.07 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 33.76 g of the varnish A obtained in Synthesis Example 1 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in the varnish A) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphate relative to 1 mole of the repeating unit of the polyimide precursor is 0.05 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Example 2]

0.14 g (1.00 mmol) of trimethyl phosphate and 0.14 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 33.76 g of the varnish A obtained in Synthesis Example 1 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in the varnish A) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphate per mole of the repeating unit of the polyimide precursor is 0.1 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Example 3]

0.28 g (2.00 mmol) of trimethyl phosphate and 0.28 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 33.76 g of the varnish A obtained in Synthesis Example 1 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in the varnish A) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphate relative to 1 mole of the repeating unit of the polyimide precursor is 0.2 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Example 4]

0.56 g (4.00 mmol) of trimethyl phosphate and 0.56 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 33.76 g of the varnish A obtained in Synthesis Example 1 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in the varnish A) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphate relative to 1 mole of the repeating unit of the polyimide precursor is 0.4 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Example 5]

0.25 g (2.00 mmol) of trimethyl phosphite and 0.25 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 33.76 g of the varnish A obtained in Synthesis Example 1 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in the varnish A) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the amount of injection, the number of moles of trimethyl phosphite was 0.2 equivalents relative to 1 mole of the repeating unit of the polyimide precursor.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Comparative Example 1]

The varnish A obtained in Synthetic Example 1 filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 410 ° C on a glass substrate under a nitrogen atmosphere (oxygen concentration of 200 ppm or less) To obtain a colorless transparent polyimide film / glass laminate. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Comparative Example 2]

0.20 g (2.00 mmol) of phosphoric acid and 0.20 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 33.76 g of the varnish A obtained in Synthesis Example 1 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in the varnish A) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of phosphoric acid is 0.2 equivalents relative to 1 mole of the repeating unit of the polyimide precursor.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Comparative Example 3]

0.65 g (2.00 mmol) of triphenyl phosphate and 0.65 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 33.76 g of the varnish A obtained in Synthesis Example 1 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in the varnish A) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of triphenyl phosphate relative to 1 mole of the repeating unit of the polyimide precursor is 0.2 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Comparative Example 4]

0.27 g (1.00 mmol) of tributyl phosphate and 0.27 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 33.76 g of the varnish A obtained in Synthesis Example 1 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in the varnish A) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of tributyl phosphate relative to 1 mole of the repeating unit of the polyimide precursor is 0.1 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-1.

[Example 6]

0.14 g (1.00 mmol) of trimethyl phosphate and 0.14 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphate per mole of the repeating unit of the polyimide precursor is 0.1 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 7]

0.28 g (2.00 mmol) of trimethyl phosphate and 0.28 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphate relative to 1 mole of the repeating unit of the polyimide precursor is 0.2 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 410 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Comparative Example 5]

The varnish B obtained in Synthesis Example 2 filtered through a PTFE membrane filter was applied to a glass substrate and heated to a temperature of from room temperature to 410 deg. C on a glass substrate under a nitrogen atmosphere (oxygen concentration of 200 ppm or less) To obtain a colorless transparent polyimide film / glass laminate. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 8]

0.14 g (1.0 mmol) of diethyl aniline and 0.14 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of diethyl cinnamate relative to 1 mole of the repeating unit of the polyimide precursor is 0.1 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 9]

0.28 g (2.0 mmol) of diethyl aniline and 0.28 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of diethyl phthalate is 0.2 equivalents relative to 1 mole of the repeating unit of the polyimide precursor.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 10]

0.55 g (4.0 mmol) of diethyl phthalate and 0.55 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of diethyl cinnamate relative to 1 mole of the repeating unit of the polyimide precursor is 0.4 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 11]

0.97 g (7.0 mmol) of diethyl azine and 0.60 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of diethyl cinnamate relative to 1 mole of the repeating unit of the polyimide precursor is 0.7 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 12]

1.38 g (10.0 mmol) of diethyl azine and 0.60 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of diethyl cinnamate relative to 1 mole of the repeating unit of the polyimide precursor is 1.0 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 13]

1.80 g (13.0 mmol) of diethyl aniline and 0.60 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of diethyl cinnamate relative to 1 mole of the repeating unit of the polyimide precursor is 1.3 equivalents.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 14]

2.76 g (20.0 mmol) of diethyl aniline and 0.60 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of diethyl cinnamate relative to 1 mole of the repeating unit of the polyimide precursor is 2.0 equivalents.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 15]

0.44 g (4.0 mmol) of dimethyl phosphite and 0.44 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the amount of injection, the number of moles of dimethyl phosphite per mole of the repeating unit of the polyimide precursor is 0.4 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 16]

2.48 g (20.0 mmol) of trimethyl phosphite and 0.50 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphite is 2.0 equivalents relative to 1 mole of the repeating unit of the polyimide precursor.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 17]

4.96 g (40.0 mmol) of trimethyl phosphite and 0.50 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphite is 4.0 equivalents relative to 1 mole of the repeating unit of the polyimide precursor.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Comparative Example 6]

The varnish B obtained in Synthetic Example 2 filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 420 ° C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) To obtain a colorless transparent polyimide film / glass laminate. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Comparative Example 7]

0.31 g (1.0 mmol) of triphenyl phosphite and 0.31 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of triphenyl phosphite relative to 1 mole of the repeating unit of the polyimide precursor is 0.1 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Comparative Example 8]

1.24 g (4.0 mmol) of triphenyl phosphite and 1.24 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.39 g of varnish B obtained in Synthesis Example 2 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish B) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of triphenyl phosphite relative to 1 mole of the repeating unit of the polyimide precursor is 0.4 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 420 deg. C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 18]

0.14 g (1.0 mmol) of trimethyl phosphate and 0.14 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 24.94 g of the varnish C obtained in Synthesis Example 3 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish C) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphate per mole of the repeating unit of the polyimide precursor is 0.1 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 400 DEG C on a glass substrate in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Comparative Example 9]

The varnish C obtained in Synthesis Example 3 filtered through a PTFE membrane filter was applied to a glass substrate and heated in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) from a room temperature to 400 캜 on a glass substrate as it was to thermally imidize To obtain a colorless transparent polyimide film / glass laminate. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Example 19]

0.28 g (2.0 mmol) of trimethyl phosphate and 0.28 g of N-methyl-2-pyrrolidone were added to the reaction vessel to obtain a homogeneous solution. 35.95 g of varnish D obtained in Synthesis Example 4 (10 millimoles of the molecular weight of the repeating unit of the polyimide precursor in varnish D) was added to the solution, and the mixture was stirred at room temperature for 3 hours to obtain a uniform and viscous polyimide precursor solution . Calculated from the injection amount, the number of moles of trimethyl phosphate relative to 1 mole of the repeating unit of the polyimide precursor is 0.2 equivalent.

The polyimide precursor solution filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidated by heating from room temperature to 370 占 폚 in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) on a glass substrate as it was, A polyimide film / glass laminate was obtained. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Comparative Example 10]

The varnish D obtained in Synthetic Example 4 filtered through a PTFE membrane filter was applied to a glass substrate and thermally imidized by heating from room temperature to 370 占 폚 in a nitrogen atmosphere (oxygen concentration of 200 ppm or less) To obtain a colorless transparent polyimide film / glass laminate. Then, the obtained polyimide film / glass laminate was immersed in water, peeled off, and dried to obtain a polyimide film having a thickness of about 10 mu m.

The properties of the polyimide film were measured and the results are shown in Table 2-2.

[Table 2-1]

[Table 2-2]

From the results shown in Tables 2-1 to 2-2, it was confirmed that the compounds containing phosphorus compounds (trimethyl phosphate, trimethyl phosphite, dimethyl phosphite, or diethyl phosphite) having a boiling point at 1 atm lower than the decomposition temperature, It is found that the polyimide obtained from the polyimide precursor composition is equivalent to the polyimide obtained from the polyimide precursor composition containing no compound having transparency and has higher heat resistance (Examples 1 to 5 and Comparative Example 1, Examples 6 to 17 and Comparative Examples 5 and 6, Example 18 and Comparative Example 9, Example 19 and Comparative Example 10). On the other hand, when the compound (phosphoric acid, tributyl phosphate) having a boiling point at 1 atm is higher than the decomposition temperature or a phosphorus compound (triphenyl phosphate, triphenyl phosphite) having a boiling point exceeding 350 ° C at 1 atm (Comparative Example 1, Comparative Example 2, 3 to 4, Comparative Example 5, Comparative Example 5, Comparative Example 5, Comparative Example 5, Comparative Example 6, 6 and Comparative Examples 7 and 8).

As described above, the polyimide film obtained from the polyimide precursor composition of the present invention has excellent light transmittance and mechanical characteristics, has a high heat resistance, and has a low thermal expansion coefficient. Thus, And can be preferably used as a transparent substrate capable of forming a colorless transparent and fine circuit such as an application.

Industrial availability

According to the present invention, a polyimide precursor composition (solution composition containing a polyimide precursor) that can obtain a polyimide having higher heat resistance even with the same composition as polyimide excellent in transparency and mechanical properties, and a method of producing polyimide Can be provided. The polyimide obtained from the polyimide precursor composition has high transparency, has a higher heat resistance, and has a low coefficient of linear thermal expansion, so that it is easy to form a fine circuit. Particularly, polyimide obtained from the polyimide precursor composition can be used for forming a substrate for a display, Can be preferably used.

Claims (8)

A polyimide precursor containing at least one of a repeating unit represented by the following formula (1), a repeating unit represented by the following formula (2), or a repeating unit represented by the following formula (3)
Phosphorus atom, and has a boiling point at 1 atm lower than the decomposition temperature, and further contains a phosphorus compound at 350 deg. C or lower.
[Chemical Formula 1]

(Wherein X < _{1 >} Is a quadrivalent group having an alicyclic structure, Y ₁ And R &_lt; ₂ > are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkyl silyl group having 3 to 9 carbon atoms.
(2)

(Wherein X ₂ is a tetravalent group having an aromatic ring, Y ₂ is a divalent group having an alicyclic structure, R ₃ and R ₄ are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, 9 < / RTI >
(3)

(Wherein X ₃ is a tetravalent group having an aromatic ring and Y ₃ is a divalent group having an aromatic ring provided that at least one of X ₃ and Y ₃ contains a fluorine atom and R ₅ and R ₆ Are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylsilyl group having 3 to 9 carbon atoms. The method according to claim 1,
Wherein the phosphorus compound has a boiling point of 200 占 폚 or less at 1 atm. 3. The method according to claim 1 or 2,
Wherein the phosphorus compound is any one of trimethyl phosphate, trimethyl phosphite, dimethyl phosphite, and diethyl phosphite. A process for producing a polyimide, characterized in that the polyimide precursor composition according to any one of claims 1 to 3 is heat-treated to imidize the polyimide precursor. 5. The method of claim 4,
A process for producing a polyimide precursor composition, comprising the steps of: applying the polyimide precursor composition according to any one of claims 1 to 3 onto a substrate;
A process for producing a polyimide characterized by having a step of heat-treating a polyimide precursor composition on a substrate to imidize the polyimide precursor. A polyimide produced by the method according to claim 4 or 5. A polyimide film produced by the method according to claim 4 or 5. A substrate for a display, a touch panel, or a solar cell, comprising the polyimide according to claim 6 or the polyimide film according to claim 7.