Polyimide precursor composition and method for producing polyimide molded body

Abstract

To provide a polyimide precursor composition that enables efficient formation of an intermediate molded body for forming a polyimide molded body through heating at a relatively low temperature.SOLUTION: A polyimide precursor composition comprises a polyimide precursor and an organic solvent that is at least one of a cyclic ketone and a cyclic ether. The polyimide precursor includes a structural unit represented by formula (I). At least one of X1 and X2 includes a group represented by formula (10).SELECTED DRAWING: None

Description

Technical Field

[0001] The present disclosure relates to a polyimide precursor composition and a method for producing a polyimide molded article.

Background Art

[0002] Polyimide films are widely applied in various electronic components as protective films for protecting wirings or members such as substrates. A polyimide film can be formed by heating a resin film formed using a polyimide precursor having an amide group derived from an acid anhydride and a varnish containing an organic solvent (for example, Patent Documents 1 and 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Since the types of organic solvents in which the polyimide precursor dissolves appropriately are limited, in order to form a varnish containing the polyimide precursor, it has been necessary to use polar organic solvents having a high boiling point, such as N-methyl-2-pyrrolidone (NMP) and γ-butyrolactone. In order to sufficiently remove the organic solvent having a high boiling point and form an intermediate molded article for forming a polyimide molded article, heating at a high temperature is required. In addition, there is also a possibility that an organic solvent having a high boiling point remains in the polyimide molded article containing polyimide formed from the polyimide precursor.

[0005] The present disclosure relates to a polyimide precursor composition capable of efficiently forming an intermediate molded article for forming a polyimide molded article by heating at a relatively low temperature.

Means for Solving the Problems

[0006] The present disclosure includes the following. [1] A polyimide precursor, At least one organic solvent of a cyclic ketone or a cyclic ether, and the polyimide precursor has the following formula (I):

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Advantages of the Invention

[0007] A polyimide precursor composition capable of efficiently forming an intermediate molded body for forming a polyimide molded body by heating at a relatively low temperature can be provided.

Modes for Carrying Out the Invention

[0008] The present invention is not limited to the following examples.

[0009] The polyimide precursor composition contains a polyimide precursor and at least one organic solvent of a cyclic ketone or a cyclic ether.

[0010] An example of the polyimide precursor is the following formula (I):

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0011] The polyimide precursor can be a polymer having a polymer chain composed of a plurality of continuously bonded structural units including a structural unit represented by formula (I). The polymer chain of the polyimide precursor may contain structural units other than the structural unit represented by formula (I). The proportion of the structural unit represented by formula (I) in the polyimide precursor may be 30% by mass or more, 50% by mass or more, 70% by mass or more, 90% by mass or more, or 95% by mass or more based on the mass of the polyimide precursor, and may be 100% by mass or less.

[0012] X 1 When X contains a dicyclopentadienediyl group, X 1 is an organic group containing a group represented by the following formula (II):

Chemical formula

[0013] X 3 may be an alicyclic group (e.g., cyclohexane ring) which may have a substituent, or an aromatic group (e.g., benzene ring) which may have a substituent. X 3 The substituent of the alicyclic group or aromatic group as X may be an alkyl group having 1 to 5 carbon atoms (e.g., methyl group), or an alkenyl group having 1 to 5 carbon atoms (e.g., allyl group). X 3 may be a residue of a tricarboxylic anhydride. X 3 Examples of the tricarboxylic anhydride from which is derived include cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride, trimellitic anhydride, octahydro-4-methyl-1,3-dioxo-5-isobenzofurancarboxylic acid (cas:185855-13-4), and 1,3-dihydro-4-methyl-1,3-dioxo-5-isobenzofurancarboxylic acid (cas:185855-21-4).

[0014] L may be a direct bond, or a linker group selected from a carboxylic acid ester group (-C(=O)O-) and a carboxylic acid amide group (-C(=O)NH-).

[0015] Ar 1 and Ar 2 are aromatic groups which may have a substituent, and may be, for example, a phenylene group or a biphenylene group. Ar 1 or Ar 2 The substituent of the aromatic group as Ar may be an alkyl group having 1 to 5 carbon atoms (e.g., methyl group), or an alkenyl group having 1 to 5 carbon atoms (e.g., allyl group).

[0016] Specific examples of the group represented by formula (II) include the groups represented by the following formula (IIa) or (IIb). In formula (IIa) or (IIb), * represents a linker similar to * in formula (II). R 3 and R4 each independently represents an alkyl group having 1 to 5 carbon atoms (e.g., methyl group) or an alkenyl group having 1 to 5 carbon atoms, p represents an integer from 0 to 4, q represents an integer from 0 to 3, and n represents an integer of 0 or more. p may be 0 or 1. q may be 0. n may be 10 or less.

Chemical formula

Chemical formula

[0017] X containing a dicyclopentadienediyl group 1 may be a group represented by the following formula (III).

Chemical formula

[0018] In formula (III), * represents a bond, and L and X 3 are the same as L and X in formula (II) 3 and are defined in the same way, R 5 represents a divalent organic group (e.g., a linear, branched or cyclic saturated aliphatic group which may have a substituent, or an aromatic group which may have a substituent), and X 4 represents an aromatic group which may have a substituent (e.g., phenylene group, biphenylene group, etc.), an alicyclic group which may have a substituent (e.g., cyclohexanediyl group, etc.), or a group containing an aromatic group which may have a substituent and an alkanediyl group having 1 to 3 carbon atoms connecting two or more such aromatic groups. The substituent which the aromatic group or alicyclic group contained in X 4 may have is, for example, an alkyl group having 1 to 5 carbon atoms (e.g., methyl group) or an alkenyl group having 1 to 5 carbon atoms (e.g., allyl group).

[0019] Specific examples of the group represented by formula (III) include the group represented by the following formula (IIIa). R in formula (IIIa) 5 and n are defined in the same way as R 5 and n in formula (II). R 6represents a hydrogen atom, an alkyl group having 1 to 5 carbon atoms (such as a methyl group), or an alkenyl group having 1 to 5 carbon atoms (such as an allyl group).

Chemical formula

[0020] The spirobiindanediyl group may be a group represented by the following formula (12a).

Chemical formula

[0021] X containing a spirobiindanediyl group 1 may be a group represented by the following formula (IV). In formula (IV), * represents a bond, and L and X 3 are the same as L and X in formula (II) 3 and are defined in the same manner, and R 11 is the same as R in formula (12) 11 and is defined in the same manner.

Chemical formula

[0022] Specific examples of the group represented by formula (IV) include groups represented by the following formula (IVa) or (IVb). R in formula (IVa) and (IVb) 11 is the same as R in formula (12) 11 and is defined in the same manner.

Chemical formula

Chemical formula

[0023] The indanediyl group may be a group represented by the following formula (13a).

Chemical formula

[0024] X containing an indenyl group 1 may be a group represented by the following formula (V). In formula (V), * represents a bond, and L and X 3 are the same as L and X in formula (II) 3 and are defined in the same manner, and R 11 is the same as R in formula (13) 11 and is defined in the same manner. Ar 3 represents an aromatic group (e.g., a phenylene group) which may have a substituent.

Chemical formula

[0025] Specific examples of the group represented by formula (V) include groups represented by the following formula (Va) or (Vb). R in formula (Va) and (Vb) 11 is the same as R in formula (13) 11 and is defined in the same manner.

Chemical formula

Chemical formula

[0026] In formula (I), when X 2 contains a dicyclopentadienediyl group, a spirobiindenyl group or an indenyl group, X 1 may be a tetravalent organic group that does not contain a dicyclopentadienediyl group, a spirobiindenyl group or an indenyl group. X that does not contain a dicyclopentadienediyl group, a spirobiindenyl group or an indenyl group 1 may be an alicyclic group other than a dicyclopentadienediyl group which may have a substituent, an aromatic group which may have a substituent, or a group containing two or more aromatic groups which may have a substituent and an alkanediyl group having 1 to 3 carbon atoms that binds them. X that does not contain a dicyclopentadienediyl group, a spirobiindenyl group or an indenyl group 1can be a residue derived from any tetracarboxylic dianhydride. X that does not contain a dicyclopentadienediyl group, a spirobiindandiy group, or an indandiy group 1 Examples of tetracarboxylic dianhydrides from which 1 is derived include pyromellitic dianhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride, 2-methyl-1,4-phenylenebis(trimellitate anhydride), p-phenylenebis(trimellitate anhydride), 4,4'-oxydiphthalic anhydride, 3,3',4,4'-biphenyltetracarboxylic acid, bis(1,3'-dioxo-1,3'-dihydroisobenzofuran-5-carboxylic acid)=1,1'-biphenyl-4,4'-diyl, 2,2',3,3',5,5'-hexamethyl-[1,1'-biphenyl]-4,4'-diylbis(1,3-dioxo-1,3-dihydroisobenzofuran-5-carboxylate, 4,4'-(4,4'-isopropylidenediphenoxy)diphthalic anhydride, and 2,2-bis(4-hydroxyphenyl)propanedibenzoate-3,3',4,4'-tetracarboxylic dianhydride.

[0027] X 2 When X contains a dicyclopentadienediyl group, a spirobiindandiy group, or an indandiy group, X 2It can be a residue of any diamine compound containing a dicyclopentadienediyl group, a spirobiindandiy group or an indandiy group. Examples of diamine compounds containing a dicyclopentadienediyl group, a spirobiindandiy group or an indandiy group include octahydro-4,7-methano-1H-indene-1,5-dimethanamine, octahydro-4,7-methano-1H-indene-2,5-dimethanamine, octahydro-4,7-methano-1H-indene-1,6-dimethanamine, octahydro-4,7-methano-1H-indene-1,2-dimethanamine, octahydro-4,7-methano-1H-indene-1,1-dimethanamine, 4-[4-[6-(4-aminophenoxy)-2,3-dihydro-1,3,3-trimethyl-1H-indene-1-yl]phenoxy]-benzenamine, 4,4'-[(2,2',3,3'-tetrahydro-3,3,3',3'-tetramethyl-1,1'-spirobi[1H-indene]-6,6'-diyl)bis(oxy)bis-benzenamine, 2,2',3,3'-tetrahydro-3,3,3',3'-tetramethyl-1,1'-spirobi[1H-indene]-6,6'-diamine, and 3-(4-aminophenyl)-2,3-dihydro-1,1,3-trimethyl-1H-indene-5-amine.

[0028] In formula (I), X 1 When it contains a dicyclopentadienediyl group, a spirobiindandiy group or an indandiy group, X 2 may be a divalent organic group that does not contain a dicyclopentadienediyl group, a spirobiindandiy group and an indandiy group. X that does not contain a dicyclopentadienediyl group, a spirobiindandiy group and an indandiy group 2may be an alicyclic group other than a dicyclopentadienediyl group which may have a substituent, an aromatic group which may have a substituent, or a group containing two or more aromatic groups or alicyclic groups which may have a substituent and a divalent group (for example, an alkanediyl group having 1 to 3 carbon atoms, an oxy group, a sulfonyl group, or a thio group) bonding them, an alkanediyl group which may have a substituent, a polyoxyalkylene group, or a siloxane group. X excluding a dicyclopentadienediyl group, a spirobiindandiy group, and an indandiy group 2 can be a residue derived from an arbitrary diamine compound. X excluding a dicyclopentadienediyl group, a spirobiindandiy group, and an indandiy group 2Examples of diamine compounds that induce include 4,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl methane, 4,4'-methylenebis(cyclohexylamine), 3,4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl methane, 3,4'-diaminodiphenyl sulfone, 4,4'-diaminodiphenyl sulfone, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 1,4-bis(4-aminophenoxy)benzene, m-phenylenediamine, p-phenylenediamine, 1,5-naphthalenediamine, 2,6-naphthalenediamine, bis(4-aminophenoxyphenyl) sulfone, bis(3-aminophenoxyphenyl) sulfone, bis(4-aminophenoxy)biphenyl, bis{4-(4-aminophenoxy)phenyl} ether, 1,4-bis(4-aminophenoxy)benzene, benzidine, 2,2'-dimethyl-4,4'-diaminobiphenyl, 2,2'-diethyl-4,4'-diaminobiphenyl, 2,2'-ditrifluoromethyl-4,4'-diaminobiphenyl, 3,3'-dimethyl-4,4'-diaminobiphenyl, 3,3'-diethyl-4,4'-diaminobiphenyl, 3,3'-ditrifluoromethyl-4,4'-diaminobiphenyl, 2,2',3,3'-tetramethyl-4,4'-diaminobiphenyl, 3,3',4,4'-tetramethyl-4,4'-diaminobiphenyl, bis(3-amino-4-hydroxyphenyl) sulfone, bis(3-amino-4-hydroxyphenyl) propane, bis(3-amino-4-hydroxyphenyl)methylene, bis(3-amino-4-hydroxyphenyl) ether, bis(3-amino-4-hydroxy)biphenyl, bis(3-amino-4-hydroxyphenyl)fluorene, bis(3-aminopropyl)tetramethyldisiloxane, bis(p-amino-phenyl)octamethylpentasiloxane, and ethylenediamine, 1,3-diaminopropane, 2-methyl-1,3-propanediamine, 1,4-diaminobutane, 1,5-diaminopentane, 2-methyl-1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1,8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, 1,11-diaminoundecane, 1,It contains 1,2-diaminododecane and 1,2-bis(2-aminoethoxy)ethane.,

[0029] R in formula (I) 1 and R 2 is a hydrogen atom or a monovalent organic group. R 1 and R 2 may each independently be a hydrogen atom, a linear or branched alkyl group having 1 to 20 carbon atoms which may have a substituent, a cycloalkyl group having 3 to 20 carbon atoms which may have a substituent, or an alkylsilyl group having 3 to 9 carbon atoms which may have a substituent.,

[0030] R 1 or R 2 at least one of them may contain a photopolymerizable unsaturated group. R 1 and R 2 containing a photopolymerizable unsaturated group may be, for example, an alkyl group having 1 to 10 carbon atoms having an acryloyloxy group as a substituent, or an alkyl group having 1 to 10 carbon atoms having a methacryloyloxy group as a substituent.,

[0031] The weight average molecular weight of the polyimide precursor may be 5000 or more and 100000 or less. The weight average molecular weight of the polyimide precursor may be 6000 or more, 7000 or more, 8000 or more, 9000 or more, 10000 or more, or 11000 or more, and may also be 90000 or less, 80000 or less, 70000 or less, 60000 or less, 50000 or less, 40000 or less, 30000 or less, or 20000 or less. The weight average molecular weight here is a conversion value based on the calibration curve of standard polystyrene determined by gel permeation chromatography (GPC).

[0032] The polyimide precursor can be synthesized by a usual method including, for example, a polymerization reaction between an acid anhydride monomer and an amine monomer. The acid anhydride monomer may contain an acid anhydride compound represented by the following formula (20), and the amine monomer may contain a diamine compound represented by the following formula (30). X in formula (20) 1 , X in formula (30) 2、or if both of these contain a dicyclopentadienediyl group, a spirobiindandiy group or an indandiy group, a polyimide precursor having a structural unit containing a dicyclopentadienediyl group, a spirobiindandiy group or an indandiy group can be obtained.

Chemical formula

[0033] The acid anhydride compound represented by formula (20) may be, for example, a compound represented by the following formula (20a), (20b), (20c) or (20d). X in formula (20a) 3 、L、Ar 1 、Ar 2 and n are the same as X in formula (II) 3 、L、Ar 1 、Ar 2 and n are defined. X in formula (20b) 3 、L、X 4 、R 5 and n are the same as X in formula (III) 3 、L、X 4 、R 5 and n are defined. X in formula (20c) 3 、L and R 11 are the same as X in formula (IV) 3 、L and R 11 and are defined. X in formula (20d) 3 、L and R 11 are the same as X in formula (V) 3 、L and R 11 and are defined.

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0034] Examples of the compound represented by formula (20a) include the acid anhydride compounds represented by the following formula (21) or (22). R in formulas (21) and (22) 3 , R 4 , p, q, and n are defined in the same manner as R 3 , R 4 , p, q, and n in formula (IIa) or (IIb).

Chemical formula

Chemical formula

[0035] Examples of the compound represented by formula (20c) include the acid anhydride compounds represented by the following formula (23) or (24). R in formulas (23) and (24) 11 is defined in the same manner as R 11 in formula (12).

Chemical formula

Chemical formula

[0036] Examples of the compound represented by formula (20d) include the acid anhydride compounds represented by the following formula (25) or (26). R in formulas (25) and (26) 11 is defined in the same manner as R 11 in formula (13).

Chemical formula

Chemical formula

[0037] A polyimide can be formed which is a polymer having a polymer chain containing a structural unit containing an imide ring by forming an imide ring in at least a part of the structural units constituting the polyimide precursor. The polyimide to be formed contains, for example, a structural unit represented by the following formula (IA). X in formula (IA) 1 and X 2 can be the same groups as X 1 and X 2 in formula (I). The imidization reaction involving the formation of an imide ring can be advanced by heating.

Chemical formula

[0038] A polyimide molded article containing polyimide can be produced by a method including forming an intermediate molded article containing a polyimide precursor and heating the intermediate molded article to form an imide ring in at least a part of the structural units represented by formula (I) in the polyimide precursor.

[0039] The intermediate molded article containing a polyimide precursor can be formed, for example, by a method including preparing a polyimide precursor composition containing a polyimide precursor and an organic solvent, imparting a shape to the polyimide precursor composition, and then removing the organic solvent from the polyimide precursor composition. The polyimide molded article may be a polyimide film. In that case, for example, a film-like intermediate molded article may be formed by a method including removing the organic solvent by heating from a resin film containing the polyimide precursor composition. A small amount of the organic solvent may remain in the intermediate molded article. The imidization reaction may proceed partially at the stage of the intermediate molded article.

[0040] The organic solvent of the polyimide precursor composition can be a cyclic ketone, a cyclic ether, or a combination thereof. Cyclic ketones and cyclic ethers often have boiling points lower than those of polar solvents such as N-methyl-2-pyrrolidone. The boiling points of cyclic ketones and cyclic ethers at 1 atm may be 200 °C or lower, 190 °C or lower, 180 °C or lower, 170 °C or lower, 160 °C or lower, 150 °C or lower, or 140 °C or lower, and may also be 40 °C or higher, 50 °C or higher, or 60 °C or higher. Examples of cyclic ketones include cyclohexanone (boiling point: 156 °C) and cyclopentanone (boiling point: 130 °C). Examples of cyclic ethers include tetrahydrofuran (boiling point: 66 °C). The content of the organic solvent in the polyimide precursor composition may be, for example, 40% by mass or more and 80% by mass or less based on the mass of the polyimide precursor composition. The polyimide precursor composition may contain only cyclic ketones and / or cyclic ethers as the organic solvent, or may further contain organic solvents other than cyclic ketones and cyclic ethers. Based on the total amount of the organic solvents contained in the polyimide precursor composition, the total amount of cyclic ketones and cyclic ethers may be 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, or 95% by mass or more, and may also be 100% by mass or less.

[0041] The concentration of the polyimide precursor in the polyimide precursor composition can be adjusted within a range such that the polyimide precursor is dissolved in the organic solvent. For example, the concentration of the polyimide precursor may be 80% by mass or less, 75% by mass or less, 70% by mass or less, 65% by mass or less, 60% by mass or less, 55% by mass or less, or 50% by mass or less based on the total amount of the polyimide precursor and the organic solvent, or the total amount of the polyimide precursor, cyclic ketones, and cyclic ethers, and may also be 5% by mass or more, 10% by mass or more, 15% by mass or more, 20% by mass or more, 25% by mass or more, or 30% by mass or more.

[0042] The polyimide precursor composition may further contain other components such as a silane coupling agent, a photo radical polymerization initiator, and a photopolymerizable monomer, if necessary.

[0043] The heating temperature for removing the organic solvent from the polyimide precursor composition to form an intermediate molded body may be, for example, 60°C or higher, or 80°C or higher, and may be 200°C or lower, or 180°C or lower. The polyimide precursor composition containing a cyclic ketone and / or a cyclic ether can efficiently form an intermediate molded body by heating at a relatively low temperature.

[0044] The heating temperature for forming a polyimide molded body from the intermediate molded body is adjusted so that the imidization reaction proceeds sufficiently. The heating temperature may be, for example, 200°C or higher and 350°C or lower. In the polyimide molded body after heating, structural units that do not form imide rings may remain.

[0045] The polyimide molded body may be a polyimide film. In that case, the polyimide film can be applied, for example, as a substrate or an insulating resin layer constituting an electronic component. The polyimide film may be a substrate (especially a transparent substrate) of an image display device. The insulating resin layer made of a polyimide film may be a protective film that protects the wiring of electronic components. Since the polyimide molded body exhibits a low dielectric tangent, it is particularly useful as a member of electronic components for high-frequency bands.

Examples

[0046] The present invention is not limited to the following examples. 1. Measurement method Infrared absorption (FT-IR) spectrum The infrared absorption spectrum of the acid anhydride compound was measured by the KBr plate method using a Fourier transform infrared spectrophotometer (FT-IR4100, manufactured by JASCO Corporation).

[0047] 1 H-NMR spectrum Of the acid anhydride compound 1 The 1H-NMR spectrum was measured using an NMR spectrometer (AV400M, manufactured by Bruker BioSpin) with deuterated dimethyl sulfoxide (DMSO-d6) as the solvent.

[0048] Weight-average molecular weight (Mw) The weight-average molecular weight (Mw) of the polyimide precursor was determined as a value converted from a calibration curve using standard polystyrene by gel permeation chromatography (GPC). The calibration curve was approximated by a cubic equation using standard polystyrene: TSKstandard POLYSTYRENE (Type; A-2500, F-4, F-10, F-40, F-850) (manufactured by Tosoh Corporation, trade name). The measurement conditions of GPC were as follows. Apparatus: High-speed GPC apparatus HLC-8320GPC (manufactured by Tosoh Corporation, trade name) Detector: Ultraviolet absorption detector UV-8320 (manufactured by Tosoh Corporation, trade name) Column; Gelpack GL-S300MDT-5×2 Eluent: DMF / tetrahydrofuran = 1:1 (vol) + 0.06M phosphoric acid + 0.06M lithium bromide Sample concentration: 10 mg / 2 mL Injection volume: 50 μL Flow rate: 1.0 mL / min Measurement temperature: 40 °C

[0049] 2. Synthesis of acid anhydride compound Example 1-1

Chemical formula

[0050] Under a nitrogen atmosphere, 7.93 g of cyclohexane-1,2,4-tricarboxylic acid-1,2-anhydride (H-TMAn-S, 40 mmol, manufactured by Mitsubishi Gas Chemical Company, Inc.), 80 mL of thionyl chloride (excess, manufactured by Tokyo Chemical Industry Co., Ltd.), and 5 drops of N,N-dimethylformamide (DMF, manufactured by Tokyo Chemical Industry Co., Ltd.) as a catalyst were placed in a 300 mL eggplant-shaped flask. The reaction was allowed to proceed by refluxing at 80 °C for 3 hours in a nitrogen atmosphere to obtain a yellow transparent solution. Toluene was added to the solution as an azeotropic agent, and thionyl chloride was distilled off by azeotropy. Crystals were formed by recrystallization in cyclohexane. The crystals were taken out by filtration and dried in vacuo at 60 °C for 12 hours to obtain white crystals containing the acid chloride formed from H-TMAn-S (yield 60%).

[0051] Under a nitrogen atmosphere, 25.62 g of dicyclopentadiene-type phenolic resin (150 mmol), 50 mL of dehydrated THF (manufactured by Fujifilm Wako Pure Chemical Corporation) without a stabilizer, and 18.2 mL of dehydrated pyridine (225 mmol, manufactured by Fujifilm Wako Pure Chemical Corporation) were placed in a 500 mL eggplant-shaped flask to form Solution A. In a 100 mL eggplant-shaped flask, 38.99 g of acid chloride (180 mmol) was dissolved in 100 mL of dehydrated THF without a stabilizer to form Solution B. While stirring Solution A in the eggplant-shaped flask in an ice bath, Solution B was slowly added dropwise to Solution A over 2 hours. The reaction solution in the eggplant-shaped flask was further stirred at room temperature for 4 hours. The precipitated precipitate was taken out by filtration and washed with THF to remove excess acid chloride. Finally, it was washed thoroughly with water to completely remove pyridine hydrochloride as a by-product. The washed precipitate was dried in vacuo at 160 °C for 12 hours to obtain a reddish-brown powder containing the product (yield 65%). From the analysis results by FT-IR and 1 1H-NMR, it was confirmed that the product was an acid anhydride compound represented by the formula (21a). FT-IR (KBr plate method, cm-1): 2951 (aromatic C-H stretching), 1863 / 1786 (acid anhydride group, C=O stretching), 1751 (ester group, C=O stretching). 1H-NMR (400 MHz, DMSO-d6, δ, ppm): 7.02 - 7.25 (m, 8H), 3.52 (m, 2H), 3.28 (m, 2H), 1.25 - 2.78 (m, 28H).

[0052] Example 1-2

Chemical formula

[0053] Under a nitrogen atmosphere, 29.00 g of dicyclopentadiene-type paracresol resin (150 mmol), 50 mL of dehydrated THF without stabilizer (manufactured by FUJIFILM Wako Pure Chemical Corporation), and 18.2 mL of dehydrated pyridine (225 mmol, manufactured by FUJIFILM Wako Pure Chemical Corporation) were placed in a 500 mL eggplant-shaped flask to form Solution A. In a 100 mL eggplant-shaped flask, 41.06 g of trimellitic anhydride chloride (195 mmol, manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in 100 mL of dehydrated THF without stabilizer to form Solution B. While stirring Solution A in the eggplant-shaped flask in an ice bath, Solution B was slowly added dropwise to Solution A over 2 hours. The reaction solution in the eggplant-shaped flask was further stirred at room temperature for 4 hours. The precipitated precipitate was taken out by filtration, washed with THF to remove excess acid chloride. Finally, it was thoroughly washed with water to completely remove pyridine hydrochloride as a by-product. The washed precipitate was vacuum dried at 160 °C for 12 hours to obtain a reddish-brown powder containing the product (yield 52%). From the analysis results by FT-IR and 1H-NMR, it was confirmed that the product was an acid anhydride compound represented by formula (22a). FT-IR (KBr plate method, cm-1): 2947 (aromatic C-H stretching), 1863 / 1786 (acid anhydride group, C=O stretching), 1739 (ester group, C=O stretching). 1 H-NMR (400 MHz, DMSO-d6, δ, ppm): 8.46 - 8.4 (d, 2H), 8.39 (s, 2H), 8.18 - 8.20 (d, 2H), 7.00 - 7.10 (m, 6H), 2.70 (s, 6H), 0.98 - 2.25 (m, 14H).

[0054] Example 1-3 [Chemical formula] In the same manner as in Example 1-1, white crystals containing the acid chloride formed from H-TMAn-S were obtained. Under a nitrogen atmosphere, 12.34 g of spirobiindane-type phenol resin (SPI, 40 mmol, manufactured by JFE), 30 mL of dehydrated THF without a stabilizer (manufactured by Fujifilm Wako Pure Chemical Corporation), and 7.12 mL of dehydrated pyridine (88 mmol, manufactured by Fujifilm Wako Pure Chemical Corporation) were placed in a 200 mL eggplant-shaped flask to form Solution A. In a 100 mL eggplant-shaped flask, 18.20 g of the acid chloride (84 mmol) formed from H-TMAn-S was dissolved in 70 mL of dehydrated THF without a stabilizer to form Solution B. While stirring Solution A in the eggplant-shaped flask in an ice bath, Solution B was slowly added dropwise to Solution A over 2 hours. The reaction solution in the eggplant-shaped flask was further stirred at room temperature for 4 hours. The precipitated precipitate was taken out by filtration and washed with THF to remove the excess acid chloride. Finally, it was thoroughly washed with water to completely remove the by-product pyridine hydrochloride. The washed precipitate was vacuum dried at 160 °C for 12 hours to obtain a reddish-brown powder containing the product (yield 51%). From the analysis results by FT-IR and 1 1H-NMR, it was confirmed that the product was an acid anhydride compound represented by the formula (23a). FT-IR (KBr plate method, cm-1): 2958 (aromatic C-H stretching), 1863 / 1789 (acid anhydride group, C=O stretching), 1747 (ester group, C=O stretching). 1 1H-NMR (400 MHz, DMSO-d6, δ, ppm): 7.36 (m, 2H), 6.96 (m, 2H), 6.49 (s, 2H), 3.52 (m, 4H), 3.31 (m, 2H), 1.31 - 2.66 (m, 26H).

[0055] Example 1-4 [Chemical formula] In the same manner as in Example 1-1, white crystals containing the acid chloride formed from H-TMAn-S were obtained. Under a nitrogen atmosphere, 18.78 g of an indane-type phenol resin (TMHI, 70 mmol, manufactured by JFE) was placed in a 200 mL eggplant-shaped flask, together with 50 mL of dehydrated THF (manufactured by Fujifilm Wako Pure Chemical Corporation) containing no stabilizer and 12.46 mL of dehydrated pyridine (154 mmol, manufactured by Fujifilm Wako Pure Chemical Corporation) to form Solution A. In a 100 mL eggplant-shaped flask, 31.84 g of the acid chloride (147 mmol) formed from H-TMAn-S was dissolved in 70 mL of dehydrated THF containing no stabilizer to form Solution B. While stirring Solution A in the eggplant-shaped flask in an ice bath, Solution B was slowly added dropwise to Solution A over 2 hours. The reaction solution in the eggplant-shaped flask was further stirred at room temperature for 4 hours. The precipitated precipitate was taken out by filtration and washed with THF to remove excess acid chloride. Finally, it was thoroughly washed with water to completely remove pyridine hydrochloride as a by-product. The washed precipitate was vacuum-dried at 160 °C for 12 hours to obtain a reddish-brown powder containing the product (yield 55%). FT-IR and 1 From the analysis results by H-NMR, it was confirmed that the product was an acid anhydride compound represented by the formula (25a). FT-IR (KBr plate method, cm-1): 2954 (aromatic C-H stretching), 1863 / 1786 (acid anhydride group, C=O stretching), 1747 (ester group, C=O stretching). 1 H-NMR (400 MHz, DMSO-d6, δ, ppm): 7.26~7.28 (m, 3H), 6.99~7.02 (d, 4H), 3.35~3.50 (m, 4H), 3.08 (m, 2H), 1.29~2.65 (m, 17H), 1.15 (s, 3H), 0.95 (s, 3H).

[0056] 3. Synthesis of polyimide precursor Example 2-1 In a dry and sealed reaction vessel, a powder (10 mmol) containing the acid anhydride compound represented by the formula (21a) synthesized in Example 1-1 was dissolved in NMP dehydrated with molecular sieves 4A. While stirring the formed solution with a magnetic stirrer, an NMP solution containing 4,4'-diaminodiphenyl ether (4,4'-ODA, 10 mmol) was added to the solution, and stirring was continued. The total concentration of the acid anhydride compound and 4,4'-ODA was 30% by mass. By stirring at room temperature for 24 hours, a uniform and viscous varnish containing a polyimide precursor was obtained. The weight average molecular weight (Mw) of the polyimide precursor was 12,000.

[0057] Example 2-2 A varnish containing a polyimide precursor was obtained in the same procedure as in Example 2-1, except that a powder containing the acid anhydride compound represented by the formula (22a) synthesized in Example 1-2 was used as the acid anhydride compound. The weight average molecular weight (Mw) of the polyimide precursor was 16,000.

[0058] Example 2-3 A varnish containing a polyimide precursor was obtained in the same procedure as in Example 2-1, except that the acid anhydride compound represented by the formula (23a) synthesized in Example 1-3 was used as the acid anhydride compound. The weight average molecular weight (Mw) of the polyimide precursor was 7,900.

[0059] Example 2-4 A varnish containing a polyimide precursor was obtained in the same procedure as in Example 2-1, except that the acid anhydride compound represented by the formula (25a) synthesized in Example 1-4 was used as the acid anhydride compound. The weight average molecular weight (Mw) of the polyimide precursor was 4,700.

[0060] Comparative Example 1 A varnish containing a polyimide precursor was obtained in the same procedure as in Example 2-1, except that 1,2,4,5-cyclohexanetetracarboxylic dianhydride (H-PMDA) was used as the acid anhydride compound. The weight average molecular weight (Mw) of the polyimide precursor was 30,000.

Chemical formula

[0061] Comparative Example 2 A varnish containing a polyimide precursor was obtained in the same procedure as in Example 2-1, except that 1,2,4,5-cyclohexanetetracarboxylic dianhydride (H-PMDA) was used as the acid anhydride compound and 4,4'-diaminodiphenylmethane (MDA) was used as the amine. The weight average molecular weight (Mw) of the polyimide precursor was 24,000.

[0062] Comparative Example 3 A varnish containing a polyimide precursor was obtained in the same procedure as in Example 2-1, except that pyromellitic dianhydride (PMDA) was used as the acid anhydride compound and 4,4'-methylenebis(cyclohexylamine) (DCHM) was used as the amine. The weight average molecular weight (Mw) of the polyimide precursor was 15,000.

Chemical Formula

[0063]

Table 1

[0064] The evaluation results of solubility are shown in Table 1. In the table, "OK" indicates that there was no residue after dissolution, and "NG" indicates that there was a residue after dissolution. It was confirmed that the polyimide precursor of the example showed good solubility in cyclic ketones and cyclic ethers. This is presumably because the introduction of bulky skeletons such as dicyclopentadienediyl group, spirobiindandiy group, and indandiy group weakened the interaction between polymer chains, and as a result, the organic solvent easily penetrated into the crystals of the polyimide precursor.

Claims

1. A polyimide precursor, at least one organic solvent selected from cyclic ketones or cyclic ethers, and the polyimide precursor has the following formula (I): 【Chemical Formula 1】 contains a structural unit represented by, where X １ represents a tetravalent organic group, X ２ represents a divalent organic group, R １ and R ２ each independently represent a hydrogen atom or a monovalent organic group, and at least one of X １ or X ２ has the following formula (10): 【Chemical Formula 2】 represents a dicyclopentadienediyl group represented by the following formula (12): 【Chemical Formula 3】 represents a spirobiindandiy group represented by the following formula (13): 【Chemical Formula 4】 contains an indandiy group represented by, R １１ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, and a plurality of R in the same molecule １１ may be the same or different, A polyimide precursor composition.

2. The polyimide precursor composition according to claim 1, wherein the boiling points of the cyclic ketone and the cyclic ether at 1 atm are 200 °C or lower.

3. The polyimide precursor composition according to claim 1, wherein the organic solvent contains one or more selected from the group consisting of cyclohexanone, cyclopentanone, and tetrahydrofuran.

4. By removing the organic solvent from the polyimide precursor composition according to claim 1, forming an intermediate molded body containing the polyimide precursor, By heating the intermediate molded body, an imide ring is formed in at least a part of the structural units represented by the formula (I) in the polyimide precursor, thereby forming a polyimide molded body containing polyimide. A method for producing a polyimide molded body, comprising:

5. The method according to claim 4, wherein the intermediate molded body is a resin film and the polyimide molded body is a polyimide film.

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