Method for producing polynorbornene

Abstract

To provide a method for producing polynorbornene which can yield the polynorbornene having a small weight average molecular weight and excellent compatibility with other materials, in high yield and with excellent safety.SOLUTION: A method for producing polynorbornene includes the step of polymerizing a norbornene compound in a solvent in the presence of a palladium catalyst and a chain transfer agent. The solvent does not contain toluene or trifluoro toluene, or the contents of them are below the detection limits in GC / MS measurement. The difference between the Hansen solubility parameter a of the polynorbornene and the Hansen solubility parameter b of the solvent is 8 or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a method for producing polynorbornene, a polynorbornene-containing solution, a polynorbornene powder, a photosensitive resin composition, and a semiconductor device. [Background technology]

[0002] BACKGROUND ART Norbornene-based resins have been used for a variety of applications as molded articles because of their excellent electrical properties, optical properties, and low moisture absorption.

[0003] Patent Document 1 discloses a norbornene-based polymer or a polymer composition containing a norbornene-based polymer. Specifically, it describes an example of homopolymerization of 1-[4-(5-2-norbornyl)butyl]-3,4-dimethyl-pyrrole-2,5-dione (NBBuDMMI) in toluene (paragraphs 0173 and 0176).

[0004] Patent Document 2 discloses a block copolymer of a specific structure. Specifically, it describes an example of homopolymerization of NBBuDMMI in trifluorotoluene in the presence of a specific palladium catalyst, in which synthesis is carried out using 1 mole of the specific palladium catalyst per 100 moles of NBBuDMMI (paragraphs 0251 and 0253).

[0005] Furthermore, polyimide resins have high mechanical strength, heat resistance, insulating properties, and solvent resistance, and are therefore widely used as protective materials in liquid crystal display elements and semiconductors, insulating materials, and thin films for electronic materials such as color filters. Patent Document 3 discloses a photosensitive composition containing a polyimide having a specific maleimide group at the end. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Special Publication No. 2013-541191 [Patent Document 2] Special Publication No. 2017-525808 [Patent Document 3] International Publication No. 2020 / 181021 Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the conventional manufacturing method described in Patent Document 1, the weight-average molecular weight of the obtained polymer is high, and there is room for improvement in compatibility with other materials. Furthermore, the reaction is carried out in toluene, and toluene remains in the obtained polymer. That There was a problem.

[0008] In the conventional production method described in Patent Document 2, although the weight-average molecular weight of the obtained polymer is small, the conversion rate is low despite the long reaction time (20 hours), and there is room for improvement in the polymer yield. Furthermore, the reaction is carried out in trifluorotoluene, and trifluorotoluene remains in the obtained polymer. That There was a problem. [Means for solving the problem]

[0009] The present inventors have found that the above-mentioned problems can be solved by polymerizing a norbornene-based compound in a predetermined solvent other than toluene and trifluorotoluene in the presence of a palladium catalyst and a chain transfer agent, and have completed the present invention. That is, the present invention can be shown as follows.

[0010] According to the present invention, The method includes a step of polymerizing a norbornene-based compound in a solvent in the presence of a palladium catalyst and a chain transfer agent to obtain polynorbornene, The solvent does not contain toluene and trifluorotoluene or is below the detection limit in GC / MS measurement, The method for producing polynorbornene is provided, wherein the difference between the Hansen solubility parameter a of the polynorbornene and the Hansen solubility parameter b of the solvent is 8 or less.

[0011] According to the present invention, A polynorbornene-containing solution is provided which contains a polynorbornene containing a structural unit represented by the following general formula (1a), and which does not contain toluene and trifluorotoluene or contains toluene and trifluorotoluene at levels below the detection limit in GC / MS measurement. [ka] (In general formula (1a), R 1 and R 2 each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and Q 1 represents a single bond or a divalent organic group, and G 1 , G 2 , and G 3 each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms; and m is 0, 1, or 2.

[0012] According to the present invention, There is provided a polynorbornene powder containing a structural unit represented by the general formula (1a), which is free of toluene and trifluorotoluene or contains toluene and trifluorotoluene at levels below the detection limit in GC / MS measurement.

[0013] According to the present invention, A photosensitive resin composition is provided, which contains the polynorbornene powder and a polyimide.

[0014] According to the present invention, A cured film is provided which is made of a cured product of the photosensitive resin composition.

[0015] According to the present invention, There is also provided a semiconductor device comprising a resin film containing a cured product of the photosensitive resin composition. [Effects of the Invention]

[0016] According to the present invention, polynorbornene having a small weight-average molecular weight and excellent compatibility with other materials can be obtained in high yield. stomach Furthermore, according to the present invention, a method for producing polynorbornene can be provided. R Furthermore, according to the present invention, since polynorbornene has excellent compatibility with other materials, a photosensitive resin composition containing polynorbornene and polyimide can be provided. [Brief explanation of the drawings]

[0017] [Figure 1] 1 is a schematic cross-sectional view of a semiconductor device according to an embodiment of the present invention; DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are denoted by similar reference numerals, and their description will be omitted where appropriate. For example, "1 to 10" represents "1 or more" to "10 or less" unless otherwise specified.

[0019] The method for producing polynorbornene according to the present embodiment includes a step of polymerizing a norbornene-based compound in a solvent in the presence of a palladium catalyst and a chain transfer agent. In this embodiment, for example, a norbornene-based compound, a palladium catalyst, and a chain transfer agent are dissolved in a solvent, and then the solution is heated for a predetermined period of time, thereby carrying out solution polymerization. At this time, the heating temperature can be, for example, 30°C to 120°C, preferably 40°C to 100°C, and more preferably 50°C to 80°C.

[0020] The heating time can be, for example, 0.5 to 10 hours. It is more preferable to carry out solution polymerization after removing moisture from the reaction system by nitrogen aeration.

[0021] (Norbornene compounds) As the norbornene-based compound of this embodiment, any known norbornene-based compound can be used as long as the effects of the present invention are achieved, but it is preferable to use a compound represented by the following general formula (1).

[0022] [ka]

[0023] In general formula (1), R 1 and R 2 are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and at least one of them is preferably an alkyl group having 1 to 3 carbon atoms, and more preferably both are alkyl groups having 1 to 3 carbon atoms. From the viewpoint of the effects of the present invention, the alkyl group having 1 to 3 carbon atoms is preferably an alkyl group having 1 or 2 carbon atoms, and more preferably an alkyl group having 1 carbon atom.

[0024] Q 1 represents a single bond or a divalent organic group. The divalent organic group can be any known organic group as long as it achieves the effects of the present invention, and examples thereof include an alkylene group having 1 to 8 carbon atoms or a (poly)alkylene glycol chain. The alkylene group having 1 to 8 carbon atoms is preferably an alkylene group having 2 to 6 carbon atoms.

[0025] Examples of the alkylene group having 1 to 8 carbon atoms include a methylene group, an ethylene group, a propylene group, a butylene group, a pentylene group, a hexylene group, a heptylene group, and an octylene group.

[0026] The alkylene oxide constituting the (poly)alkylene glycol chain is not particularly limited, but is preferably an alkylene oxide having 1 to 18 carbon atoms, and more preferably an alkylene oxide having 2 to 8 carbon atoms, and examples thereof include ethylene oxide, propylene oxide, butylene oxide, isobutylene oxide, 1-butene oxide, 2-butene oxide, trimethylethylene oxide, tetramethylene oxide, tetramethylethylene oxide, butadiene monoxide, and octylene oxide.

[0027] G 1 , G 2 , and G 3 each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms.

[0028] Examples of the hydrocarbon group having 1 to 30 carbon atoms include an alkyl group, an alkenyl group, an alkynyl group, an alkylidene group, an aryl group, an aralkyl group, an alkaryl group, and a cycloalkyl group.

[0029] Examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, neopentyl, hexyl, heptyl, octyl, nonyl, and decyl groups. Alkenyl groups include, for example, allyl, pentenyl, and vinyl groups, and alkynyl groups include ethynyl groups. Alkylidene groups include, for example, methylidene and ethylidene groups.

[0030] Aryl groups include, for example, phenyl, naphthyl, and anthracenyl groups, and aralkyl groups include, for example, benzyl and phenethyl groups.

[0031] Examples of the alkaryl group include tolyl and xylyl groups, and examples of the cycloalkyl group include adamantyl, cyclopentyl, cyclohexyl, and cyclooctyl groups. The hydrocarbon group having 1 to 30 carbon atoms may contain at least one atom selected from O, N, S, P and Si in its structure.

[0032] In this embodiment, the hydrocarbon group having 1 to 30 carbon atoms is preferably a hydrocarbon group having 1 to 15 carbon atoms, and more preferably a hydrocarbon group having 1 to 10 carbon atoms. Furthermore, the hydrocarbon group having 1 to 30 carbon atoms is preferably an alkyl group having 1 to 30 carbon atoms, more preferably an alkyl group having 1 to 15 carbon atoms, and even more preferably an alkyl group having 1 to 10 carbon atoms.

[0033] Examples of the substituent of the substituted hydrocarbon group having 1 to 30 carbon atoms include a hydroxyl group, an amino group, a cyano group, an ester group, an ether group, an amide group, and a sulfonamide group, and the group may be substituted with at least one of these groups.

[0034] In this embodiment, G 1 , G 2 , and G 3 Preferably, one of the above is a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms, and the rest are hydrogen atoms, and more preferably, all are hydrogen atoms. m is 0, 1 or 2, preferably 0 or 1, and more preferably 0.

[0035] The polynorbornene of this embodiment has a low dielectric loss tangent because it contains structural units derived from the compound of general formula (1). Furthermore, the polynorbornene has a specific maleimide group in its side chain, which allows photodimerization without causing a radical reaction, allowing photopolymerization of polynorbornene units, resulting in superior mechanical strength.

[0036] (solvent) The solvent used in the polymerization reaction of this embodiment does not contain toluene or trifluorotoluene. Furthermore, in this embodiment, a solvent is used in which the difference between the Hansen solubility parameter a of the resulting polynorbornene and the Hansen solubility parameter b of the solvent (Hansen distance Ra) is 8 or less, preferably 7 or less, and more preferably 6 or less.

[0037] In this embodiment, the Hansen solubility parameter a of polynorbornene is measured by the following method. [method] To a 5 ml glass container, add 0.05 g of polynorbornene and 1 ml of any solvent selected from the evaluation solvents listed below, and after stirring for 1 hour with a mix rotor, visually evaluate the dispersibility using the following three-point scale. All evaluation solvents and the evaluation results for dispersibility in those solvents are entered into the Sphere program of the computer software HSPiP (version 5.2.02), and the Hansen solubility parameters are calculated. (Solvent for evaluation) Hexane, cyclohexane, toluene, benzyl benzoate, propylene carbonate, 1-hexene, methyl ethyl ketone, acetone, acetonitrile, ethyl acetate, propylene glycol monomethyl ether acetate, cyclohexanol, isopropyl alcohol, methanol (evaluation) 1: Completely dissolved. 2: Partially dissolves. 6: Does not dissolve.

[0038] By using a solvent having a Hansen distance with polynorbornene within a predetermined range, the solubility of polynorbornene is excellent without using toluene or trifluorotoluene, so that the synthesis reaction proceeds smoothly, and the yield is improved due to the excellent conversion rate.Furthermore, since a polynorbornene powder is obtained, the handling is excellent.

[0039] The Hansen solubility parameter is an index of solubility that indicates how much a substance dissolves in another substance. The Hansen solubility parameter can express solubility as a three-dimensional vector, specifically the dispersion term (δ D ), polarization term (δ P ), hydrogen bond term (δ H ) can be expressed as

[0040] In this embodiment, the Hansen distance Ra is calculated by the dispersion term (δ D ), polarization term (δ P ), hydrogen bond term (δ H ) is the distance between polynorbornene (A) and solvent (B) in a three-dimensional space with coordinates, and specifically, it can be calculated by the following formula. Formula: Ra=[4(δ DA -δ DB ) 2 +(δ PA -δ PB ) 2 +(δ HA -δ HB ) 2 ] 1 / 2

[0041] The smaller the value of the Hansen distance Ra, the better the compatibility between the polynorbornene (A) and the solvent (B), and it is preferable that the Hansen distance Ra is in the above range.

[0042] The solvent may be one type of solvent or a mixed solvent of two or more types of solvents. The solvent is not particularly limited as long as it satisfies the above range of the Hansen distance Ra, but from the viewpoint of the effects of the present invention, it is preferable that the solvent contains at least one selected from ether-based solvents and hydrocarbon-based solvents that do not contain an aromatic ring.

[0043] As the ether solvent, any known solvent can be used as long as the effects of the present invention are achieved, and it is preferable that the ether solvent contains at least one selected from, for example, cyclopentyl methyl ether and methyl tetrahydropyran. By including these solvents, powdery polynorbornene can be suitably obtained in the reprecipitation step described below.

[0044] As the hydrocarbon solvent not containing an aromatic ring, any known solvent can be used as long as the effects of the present invention are achieved, and it is preferable that the solvent contains at least one selected from, for example, cyclohexane and methylcyclohexane.

[0045] The solvent is more preferably a mixed solvent of ethyl acetate and at least one selected from cyclopentyl methyl ether, methyltetrahydropyran, cyclohexane, and methylcyclohexane.

[0046] When the solvent is a mixed solvent of two or more kinds, the difference (Hansen distance Ra) between the Hansen solubility parameter a of the polynorbornene and the Hansen solubility parameter c of the mixed solvent of two or more kinds is preferably in the above range.

[0047] (Palladium catalyst) The palladium catalyst is not particularly selected as long as it allows addition polymerization to proceed, but for example, a palladium complex may be coordinated with a phosphine or diimine ligand to form a counter anion, etc. One or more of these may be used.

[0048] Examples of the palladium complex include allylpalladium complexes such as (acetato-κ0)(acetonitrile)bis[tris(1-methylethyl)phosphine]palladium(I) tetrakis(2,3,4,5,6-pentafluorophenyl)borate and π-allylpalladium chloride dimer; Palladium organic carboxylates such as palladium acetate, propionate, maleate, and naphthoate; Palladium complexes with organic carboxylic acids, such as palladium acetate triphenylphosphine complex, palladium acetate tri(m-tolyl)phosphine complex, and palladium acetate tricyclohexylphosphine complex; Palladium organic sulfonates such as palladium dibutyl phosphite and p-toluenesulfonate; β-diketone compounds of palladium such as bis(acetylacetonato)palladium, bis(hexafluoroacetylacetonato)palladium, bis(ethylacetoacetate)palladium, and bis(phenylacetoacetate)palladium; Examples thereof include dichlorobis(triphenylphosphine)palladium, bis[tri(m-tolylphosphine)]palladium, dibromobis[tri(m-tolylphosphine)]palladium, and halide complexes of palladium such as acetonyltriphenylphosphonium complex.

[0049] Examples of the phosphine ligand include triphenylphosphine, dicyclohexylphenylphosphine, cyclohexyldiphenylphosphine, and tricyclohexylphosphine.

[0050] Examples of the counter anion include triphenylcarbenium tetrakis(pentafluorophenyl)borate, triphenylcarbenium tetrakis[3,5-bis(trifluoromethyl)phenyl]borate, triphenylcarbenium tetrakis(2,4,6-trifluorophenyl)borate, triphenylcarbenium tetraphenylborate, tributylammonium tetrakis(pentafluorophenyl)borate, N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, N,N-diethylanilinium tetrakis(pentafluorophenyl)borate, N,N-diphenylanilinium tetrakis(pentafluorophenyl)borate, and lithium tetrakis(pentafluorophenyl)borate.

[0051] The amount of the palladium catalyst can be set to 1 / 20,000 to 1 / 500 mol, preferably 1 / 10,000 to 1 / 1,000 mol, and more preferably 1 / 5,000 to 1 / 2,000 mol per 1 mol of the norbornene compound, thereby further improving the yield of polynorbornene.

[0052] In this embodiment, since a norbornene compound and a predetermined solvent are used, the amount of palladium catalyst used in the reaction is small, and the amount of residual palladium contained in the obtained polynorbornene can be reduced, so the polynorbornene has excellent dielectric properties such as dielectric loss tangent.

[0053] (chain transfer agent) In this embodiment, the chain transfer agent can be any known chain transfer agent as long as the effects of the present invention are achieved. However, it is preferable that the chain transfer agent contains at least one selected from the group consisting of a compound represented by the following general formula (a), formic acid, and oxalic acid. By using a chain transfer agent, the amount of palladium catalyst can be reduced, and furthermore, polynorbornene having a small weight average molecular weight can be obtained.

[0054] [ka]

[0055] In general formula (a), R 1 , R 2 and R 3 are each independently a hydrogen atom or an alkyl group having 1 to 20 carbon atoms, preferably an alkyl group having 1 to 10 carbon atoms, and more preferably an alkyl group having 1 to 3 carbon atoms. Examples of the compound represented by general formula (a) include trimethylsilane, triethylsilane, and tributylsilane.

[0056] The chain transfer agent can be used in an amount of preferably 5 parts by mass or more and 50 parts by mass or less, more preferably 10 parts by mass or more and 40 parts by mass or less, relative to 100 parts by mass of the norbornene-based compound.

[0057] (Other ingredients) In addition, during the reaction, a molecular weight modifier, a promoter, etc. may be added as necessary.

[0058] The co-catalyst preferably contains an ion complex containing a weakly coordinating anion salt. That is, when synthesizing the addition type norbornene-based resin, it is preferable to add a co-catalyst in addition to the catalyst. This can further increase the polymerization rate of the addition type norbornene-based monomer.

[0059] The co-catalyst is not particularly limited, but examples thereof include alkylaluminum, Lewis acids, and ionic complexes containing weakly coordinating anion (WCA) salts, and among these, ionic complexes containing weakly coordinating anion (WCA) salts are preferred.

[0060] Furthermore, the promoter is more preferably one represented by the following formula (i): [C] e [WCA] d Formula (i) (In the above formula, C represents a proton (H + ), an organic radical-containing cation, or an alkali metal, alkaline earth metal, or transition metal cation, WCA is as defined above, and e and d are numbers determined to balance the electronic charge on the overall salt complex of the cation complex (C) and the weakly coordinating anion salt (WCA), respectively.

[0061] The ionic complex containing the weakly coordinating anion (WCA) salt is not particularly limited, but may be lithium(diethyl ether) 2.5 Tetrakis(pentafluorophenyl)borate, dimethylanilinium tetrakis(pentafluorophenyl)borate, dimethylanilinium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, H(OEt2) xExamples include tetrakis(pentafluorophenyl)borate, tetrakis[(4-methyl)-α,α-bis(trifluoromethyl)benzenemethanolato-κO]aluminate, sodium tetrakis(3,5-bis(trifluoromethyl)phenyl)borate, trialkyl and triarylphosphonium tetrakis(pentafluorophenyl)borate, and trityl tetrakis(pentafluorophenyl)borate.

[0062] The amount of the co-catalyst can be 1 / 20,000 mol or more and 1 / 500 mol or less, preferably 1 / 10,000 mol or more and 1 / 1,000 mol or less, and more preferably 1 / 5,000 mol or more and 1 / 2,000 mol or less, relative to 1 mol of the norbornene-based compound, thereby further improving the yield of polynorbornene.

[0063] [Reprecipitation process, etc.]

[0064] The reaction solution containing the polynorbornene of the present embodiment can be obtained by the above steps, and can be used as a polymer solution by further diluting it with an organic solvent or the like as necessary. As the organic solvent, those exemplified in the reaction step can be used, and the organic solvent may be the same as or different from the organic solvent used in the reaction step.

[0065] Alternatively, the polymer solution may be poured into a poor solvent to reprecipitate the polynorbornene, remove unreacted monomers, and dry the resulting mixture to obtain a polynorbornene powder. Examples of poor solvents include water and alcohols such as hexane, methanol, and isopropyl alcohol, and these may also be used in combination.

[0066] The obtained polynorbornene powder can be dissolved again in an organic solvent and used as a purified product (polynorbornene-containing solution). In particular, in applications where impurities or foreign matter are a problem, it is preferable to dissolve it again in an organic solvent. The concentration of polynorbornene in the polynorbornene-containing solution (100% by weight) is not particularly limited, but is about 30 to 70% by weight.

[0067] A poor solvent is used in an amount 15 to 150 times by weight of the polynorbornene-containing solution (100% by weight). The amount of poor solvent used varies depending on the type of solvent used in polymerization. When a hydrocarbon solvent is used, the amount is 50 to 150 times, and when an ether solvent is used, the amount is 15 to 50 times. By using the above, powdered polynorbornene can be obtained.

[0068] The method for producing polynorbornene according to the present embodiment does not use toluene or trifluorotoluene as a solvent, and therefore the polynorbornene powder and the polynorbornene-containing solution do not contain these solvents. Even when toluene or trifluorotoluene is used in the synthesis of the raw material norbornene, these solvents are not used in the polynorbornene production method, so the reaction solvent does not contain toluene or trifluorotoluene or is below the detection limit in GC / MS measurement, and since the polynorbornene undergoes a purification process (reprecipitation process, etc.), the polynorbornene powder and polynorbornene-containing solution do not contain toluene or trifluorotoluene or are below the detection limit in GC / MS measurement. In particular, the polynorbornene-containing solution can be prepared by dissolving the polymer powder obtained through the reprecipitation process in a solvent, so a polynorbornene-containing solution free of toluene and trifluorotoluene can be obtained. In this embodiment, toluene and trifluorotoluene being below the detection limit means that they are below the detection limit when the purified polynorbornene is measured by gas chromatography mass spectrometry (GC / MS).

[0069] The polynorbornene of this embodiment contains a structural unit represented by the following general formula (1a).

[0070] [ka]

[0071] In general formula (1a), R 1 , R 2 , Q 1 , G 1 , G 2 , G 3 and m has the same meaning as in general formula (1).

[0072] According to the production method of this embodiment, polynorbornene with a low weight-average molecular weight can be obtained, and the weight-average molecular weight can be preferably 15,000 or less, more preferably 12,000 or less, and even more preferably 10,000 or less. The lower limit of the weight-average molecular weight is not particularly limited, but can be preferably 2,000 or more, more preferably 3,000 or more, and even more preferably 5,000 or more. When the weight average molecular weight is within the above range, the polynorbornene has excellent compatibility with other materials, for example, with polyimide, and therefore a photosensitive resin composition can be suitably obtained.

[0073] The polynorbornene has a dispersity (Mw / Mn) of, for example, 1.0 or more and 8.0 or less, preferably 1.2 or more and 5.0 or less, and more preferably 1.5 or more and 3.0 or less. When the dispersity is in the above range, the polynorbornene has even better compatibility with other materials.

[0074] In this embodiment, the weight-average molecular weight of polynorbornene can be measured by obtaining a molecular weight distribution curve using Gel Permeation Chromatography (GPC). The weight-average molecular weight (Mw), number-average molecular weight (Mn), and polydispersity index (PDI: Mw / Mn) of polynorbornene are calculated using polystyrene-equivalent values ​​obtained from a calibration curve of standard polystyrene (PS) obtained by GPC measurement. The measurement conditions for GPC are, for example, as follows. Tosoh Corporation gel permeation chromatography device HLC-8320GPC Column: TSK-GEL GMH, G2000H, SuperHM-M manufactured by Tosoh Corporation Detector: RI detector for liquid chromatography Measurement temperature: 40℃ Solvent: THF Sample concentration: 5.0 mg / ml

[0075] In the production method of this embodiment, the amount of palladium catalyst used in the reaction is small, so the amount of residual palladium contained in the obtained polynorbornene powder can be reduced, resulting in excellent dielectric properties such as dielectric loss tangent.

[0076] <Photosensitive resin composition> The photosensitive resin composition of the present embodiment contains the above-described polynorbornene powder and polyimide.

[0077] [Polyimide] In the polyimide of this embodiment, at least one of both ends is preferably a group t represented by the following general formula (t), and more preferably both ends are the group t.

[0078] [ka]

[0079] In general formula (t), R 5 and R 6 are each independently a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and from the viewpoint of the effects of the present invention, an alkyl group having 1 or 2 carbon atoms is preferred, and an alkyl group having 1 carbon atom is more preferred. * represents a bond.

[0080] Q 2 represents a divalent organic group. As the divalent organic group, any known organic group can be used as long as the effects of the present invention are achieved. For example, a divalent organic group represented by the following general formula (t-1) is preferred.

[0081] [ka]

[0082] In general formula (t-1), R1 ~R 4 each independently represents an alkyl group having 1 to 3 carbon atoms or an alkoxy group having 1 to 3 carbon atoms, and R 1 and R 2 are different groups, and R 3 and R 4 are different groups. R 1 ~R 4 From the viewpoint of the effects of the present invention, is preferably an alkyl group having 1 to 3 carbon atoms.

[0083] X 1 represents a single bond, -SO2-, -C(=O)-, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms; 1 may be the same or different.

[0084] X 1 From the viewpoint of the effects of the present invention, is preferably a single bond, a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms, and more preferably a linear or branched alkylene group having 1 to 5 carbon atoms, or a linear or branched fluoroalkylene group having 1 to 5 carbon atoms. * indicates a bond.

[0085] The polyimide of this embodiment has excellent mechanical strength because it contains a polyimide having a group t represented by general formula (t) at at least one end. Furthermore, the polyimide can be photodimerized without causing a radical reaction, resulting in even greater mechanical strength. The polyimide may also include a polyimide having a group u represented by the following general formula (u) at its terminal.

[0086] [ka]

[0087] In general formula (u), X 1 , R 1 ~R 4has the same meaning as general formula (t-1).

[0088] When the polyimide contains a polyimide having the group u, the ratio of the number of moles of group t to the total number of moles of group t and group u (t / t+u) can be 0.5 or more, preferably 0.55 or more, more preferably 0.6 or more. Within this range, the amount of polyimide components eluted during development can be reduced.

[0089] The polyimide of this embodiment preferably contains a structural unit (a1) represented by the following general formula (a1) and a structural unit (a2) represented by the following general formula (a2).

[0090] [ka]

[0091] In the general formula (a1), Y is a divalent organic group. As the divalent organic group, any known organic group can be used as long as the effects of the present invention are achieved. However, from the viewpoint of the effects of the present invention, a divalent organic group selected from the following general formula (a1-1), the following general formula (a1-2), and the following general formula (a1-3) is preferred.

[0092] [ka]

[0093] In general formula (a1-1), R 7 and R 8 each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and 7 R 8 They may be the same or different. R 7 and R 8 From the viewpoint of the effects of the present invention, is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom. R 9represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and when there are multiple R 9 They may be the same or different. R 9 From the viewpoint of the effects of the present invention, is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably a hydrogen atom. * indicates a bond.

[0094] In general formula (a1-2), R 10 and R 11 each independently represents a hydrogen atom, an alkyl group having 1 to 3 carbon atoms, or an alkoxy group having 1 to 3 carbon atoms, and 10 R 11 They may be the same or different.

[0095] R 10 and R 11 From the viewpoint of the effects of the present invention, R is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, and more preferably R 10 At least one of and R 11 At least one of R is an alkyl group having 1 to 3 carbon atoms, and more preferably, three R 10 is an alkyl group having 1 to 3 carbon atoms, and one R 10 is a hydrogen atom and three R 11 is an alkyl group having 1 to 3 carbon atoms, and one R 11 is a hydrogen atom, and particularly preferably three R 10 is a methyl group and one R 10 is a hydrogen atom and three R 11 is a methyl group and one R 11 is a hydrogen atom. * indicates a bond.

[0096] In the general formula (a1-3), Z represents an alkylene group having 1 to 5 carbon atoms or a divalent aromatic group. * indicates a bond.

[0097] [ka]

[0098] In general formula (a2), R 1 ~R 4 , X 1 has the same meaning as general formula (t-1).

[0099] The polyimide of this embodiment contains a structural unit represented by general formula (a2), which suppresses the effect on electrons in the imide ring and thus inhibits hydrolysis of the polyimide, resulting in excellent mechanical strength such as elongation and excellent solubility in organic solvents. In other words, the polyimide of this embodiment and the photosensitive resin composition containing the polyimide have an excellent balance of these properties.

[0100] The polyimide may further contain a structural unit (a3) ​​represented by the following general formula (a3).

[0101] [ka]

[0102] In general formula (a3), R 5 and R 6 are each independently a hydrogen atom, a haloalkyl group having 1 to 4 carbon atoms, or a hydroxyl group, and are preferably a hydrogen atom or a haloalkyl group having 1 to 4 carbon atoms. 5 R may be the same or different, and there may be multiple R 6 They may be the same or different.

[0103] X represents a single bond, an alkylene group having 1 to 4 carbon atoms, or a haloalkylene group having 1 to 4 carbon atoms, and is preferably a single bond or a haloalkylene group having 1 to 4 carbon atoms. m and n each independently represent 0 or 1.

[0104] In the general formula (t), Q 2 The divalent organic group may be the structural unit (a3) ​​represented by the general formula (a3) ​​above. Specific examples include divalent organic groups represented by the following general formula (t-2):

[0105] [ka]

[0106] In general formula (t-2), R 5 , R 6 , X, m, and n have the same meanings as in general formula (a3). * indicates a bond.

[0107] Specifically, the polyimide of this embodiment can contain a structural unit 1 represented by the following general formula (1).

[0108] [ka]

[0109] In general formula (1), R 1 ~R 4 , X 1 has the same meaning as in formula (t-1), and Y has the same meaning as in formula (a1).

[0110] Specifically, the polyimide of this embodiment may contain, in addition to the structural unit 1, a structural unit 2 represented by the following general formula (2).

[0111] [ka]

[0112] In general formula (2), R 5 ~R 6 , X, m, and n have the same meanings as in formula (a3), and Y has the same meaning as in formula (a1).

[0113] The weight average molecular weight of the polyimide of this embodiment is 5,000 to 200,000, and preferably 10,000 to 100,000.

[0114] [Photosensitizer] The photosensitive resin composition of the present embodiment may further contain a photosensitizer.

[0115] Examples of the photosensitizer include benzophenone-based photopolymerization initiators, thioxanthone-based photopolymerization initiators, benzyl-based photopolymerization initiators, Michler's ketone-based photopolymerization initiators, etc. Among these, benzophenone-based photopolymerization initiators or thioxanthone-based photopolymerization initiators are preferred.

[0116] Benzophenone-based photopolymerization initiators include benzophenone, 4-chlorobenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-diaminobenzophenone, 4-phenylbenzophenone, isophthalphenone, 4-benzoyl-4'-methyl-diphenyl sulfide, etc. These benzophenones and their derivatives can improve the curing speed by using tertiary amines as hydrogen donors.

[0117] Commercially available benzophenone-based photopolymerization initiators include, for example, SPEEDCUREMBP (4-methylbenzophenone), SPEEDCUREMBB (methyl-2-benzoylbenzoate), SPPEDCUREBMS (4-benzoyl-4'methyldiphenyl sulfide), SPPEDCUREPBZ (4-phenylbenzophenone), and SPPEDCUREEMK (4,4'-bis(diethylamino)benzophenone) (all trade names, manufactured by DKSH Japan Co., Ltd.).

[0118] Examples of thioxanthone-based photopolymerization initiators include thioxanthone, diethylthioxanthone, isopropylthioxanthone, and chlorothioxanthone. As diethylthioxanthone, 2,4-diethylthioxanthone is preferred, as isopropylthioxanthone, and as chlorothioxanthone, 2-chlorothioxanthone is preferred. Among these, thioxanthone-based photopolymerization initiators containing diethylthioxanthone are more preferred.

[0119] Commercially available thioxanthone-based photopolymerization initiators include, for example, Speedcure DETX (2,4-diethylthioxanthone), Speedcure ITX (2-isopropylthioxanthone), Speedcure CTX (2-chlorothioxanthone), and SPEEDCURE CPTX (1-chloro-4-propylthioxanthone) (all trade names, manufactured by DKSH Japan Co., Ltd.), and KAYACURE DETX (2,4-diethylthioxanthone) (trade name, manufactured by Nippon Kayaku Co., Ltd.).

[0120] The amount of the photosensitizer added is not particularly limited, but is preferably about 0.05 to 10 mass %, more preferably about 0.1 to 7.5 mass %, and even more preferably about 0.2 to 5 mass %, of the total solid content of the photosensitive resin composition. By setting the amount of the photosensitizer added within this range, it is possible to improve the patterning ability of the photosensitive resin layer containing the photosensitive resin composition and also improve the long-term storage stability of the photosensitive resin composition.

[0121] [Adhesion aid] The photosensitive resin composition of the present embodiment may further contain an adhesion aid. This can improve the adhesion between the substrate and the resin film or pattern formed from the photosensitive resin composition.

[0122] The adhesion aid that can be used is not particularly limited. For example, silane coupling agents such as aminosilane, epoxysilane, acrylicsilane, mercaptosilane, vinylsilane, ureidosilane, acid anhydride-functional silane, and sulfidesilane can be used. The silane coupling agents may be used alone or in combination of two or more. Among these, epoxysilanes (i.e., compounds containing both an epoxy moiety and a group that generates a silanol group upon hydrolysis in one molecule) or acid anhydride-functional silanes (i.e., compounds containing both an acid anhydride group and a group that generates a silanol group upon hydrolysis in one molecule) are preferred. The group opposite the silane of the silane coupling agent bonds with polymer A or polyimide or improves compatibility with the polymer, thereby further improving the adhesion of the resin film or pattern formed from the photosensitive resin composition to the substrate.

[0123] Examples of aminosilanes include bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropyltrimethoxysilane, N-β(aminoethyl)γ-aminopropyltriethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldimethoxysilane, N-β(aminoethyl)γ-aminopropylmethyldiethoxysilane, and N-phenyl-γ-aminopropyltrimethoxysilane.

[0124] Examples of epoxy silanes include γ-glycidoxypropyltrimethoxysilane, γ-glycidoxypropylmethyldiethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, and γ-glycidylpropyltrimethoxysilane.

[0125] Examples of the acrylic silane include γ-(methacryloxypropyl)trimethoxysilane, γ-(methacryloxypropyl)methyldimethoxysilane, and γ-(methacryloxypropyl)methyldiethoxysilane. An example of the mercaptosilane is 3-mercaptopropyltrimethoxysilane.

[0126] Examples of vinylsilanes include vinyltris(β-methoxyethoxy)silane, vinyltriethoxysilane, and vinyltrimethoxysilane. Examples of ureidosilanes include 3-ureidopropyltriethoxysilane. An example of an acid anhydride functional silane is 3-trimethoxysilylpropylsuccinic anhydride.

[0127] Examples of sulfide silanes include bis(3-(triethoxysilyl)propyl)disulfide and bis(3-(triethoxysilyl)propyl)tetrasulfide. When an adhesion aid is used, only one kind may be used, or two or more kinds may be used in combination.

[0128] The content of the adhesion aid is usually 0.01 to 10 parts by mass, and preferably 0.05 to 5 parts by mass, when the total solid content of the photosensitive resin composition is 100 parts by mass. By setting the content within this range, it is believed that the effect of the adhesion aid, that is, "adhesion", can be sufficiently obtained while maintaining a balance with other performance properties.

[0129] (solvent) The photosensitive resin composition according to this embodiment may contain a urea compound or an amide compound having a non-cyclic structure as a solvent. The solvent preferably contains, for example, a urea compound. This can further improve the adhesion between a cured product of the photosensitive resin composition and metals such as Al and Cu.

[0130] In this specification, a urea compound refers to a compound having a urea bond, i.e., a urea bond. An amide compound refers to a compound having an amide bond, i.e., an amide. Specific examples of amides include primary amides, secondary amides, and tertiary amides.

[0131] In the present embodiment, the term "non-cyclic structure" means that the compound does not have a cyclic structure such as a carbon ring, an inorganic ring, a heterocyclic ring, etc. Examples of the compound structure that does not have a cyclic structure include a linear chain structure and a branched chain structure.

[0132] Urea compounds and non-cyclic amide compounds preferably have a large number of nitrogen atoms in their molecular structure. Specifically, the number of nitrogen atoms in the molecular structure is preferably two or more. This increases the number of lone electron pairs, thereby improving adhesion to metals such as Al and Cu.

[0133] Specific examples of the structure of the urea compound include a cyclic structure and an acyclic structure. Of the above specific examples, the structure of the urea compound is preferably an acyclic structure. This can improve the adhesion between the cured product of the photosensitive resin composition and metals such as Al and Cu. The reason for this is presumed to be as follows: It is presumed that urea compounds with an acyclic structure are more likely to form coordinate bonds than urea compounds with a cyclic structure. This is thought to be because urea compounds with an acyclic structure have less constraints on molecular movement and a greater degree of freedom for deformation of the molecular structure than urea compounds with a cyclic structure. Therefore, when a urea compound with an acyclic structure is used, a strong coordinate bond can be formed, improving adhesion.

[0134] Specific examples of the urea compound include tetramethylurea (TMU), 1,3-dimethyl-2-imidazolidinone, N,N-dimethylacetamide, tetrabutylurea, N,N'-dimethylpropyleneurea, 1,3-dimethoxy-1,3-dimethylurea, N,N'-diisopropyl-O-methylisourea, O,N,N'-triisopropylisourea, O-tert-butyl-N,N'-diisopropylisourea, O-ethyl-N,N'-diisopropylisourea, O-benzyl-N,N'-diisopropylisourea, etc. Among the above specific examples, the urea compound can be used alone or in combination of two or more. As the urea compound, among the above specific examples, for example, one or more selected from the group consisting of tetramethylurea (TMU), tetrabutylurea, 1,3-dimethoxy-1,3-dimethylurea, N,N'-diisopropyl-O-methylisourea, O,N,N'-triisopropylisourea, O-tert-butyl-N,N'-diisopropylisourea, O-ethyl-N,N'-diisopropylisourea, and O-benzyl-N,N'-diisopropylisourea are preferably used, and tetramethylurea (TMU) is more preferably used. This allows for the formation of strong coordinate bonds and improved adhesion.

[0135] Specific examples of the amide compound having a non-cyclic structure include 3-methoxy-N,N-dimethylpropanamide, N,N-dimethylformamide, N,N-dimethylpropionamide, N,N-diethylacetamide, 3-butoxy-N,N-dimethylpropanamide, and N,N-dibutylformamide. The photosensitive resin composition according to this embodiment may contain, as a solvent, a solvent not having a nitrogen atom, in addition to the urea compound and the amide compound having a non-cyclic structure.

[0136] Specific examples of solvents not containing a nitrogen atom include ether solvents, acetate solvents, alcohol solvents, ketone solvents, lactone solvents, carbonate solvents, sulfone solvents, ester solvents, aromatic hydrocarbon solvents, etc. As the solvent not containing a nitrogen atom, one or a combination of two or more of the above specific examples can be used.

[0137] Specific examples of the ether solvent include propylene glycol monomethyl ether (PGME), propylene glycol monoethyl ether, ethylene glycol monoethyl ether, diethylene glycol dimethyl ether, diethylene glycol monoethyl ether, diethylene glycol, ethylene glycol diethyl ether, diethylene glycol diethyl ether, diethylene glycol dibutyl ether, dipropylene glycol monomethyl ether, and 1,3-butylene glycol-3-monomethyl ether.

[0138] Specific examples of the acetate solvent include propylene glycol monomethyl ether acetate (PGMEA), methyl lactate, ethyl lactate, butyl lactate, and methyl-1,3-butylene glycol acetate.

[0139] Specific examples of the alcohol solvent include tetrahydrofurfuryl alcohol, benzyl alcohol, 2-ethylhexanol, butanediol, and isopropyl alcohol. Specific examples of the ketone solvent include cyclopentanone, cyclohexanone, diacetone alcohol, and 2-heptanone. Specific examples of the lactone solvent include γ-butyrolactone (GBL) and γ-valerolactone. Specific examples of the carbonate solvent include ethylene carbonate and propylene carbonate. Specific examples of the sulfone solvent include dimethyl sulfoxide (DMSO) and sulfolane. Specific examples of the ester solvent include methyl pyruvate, ethyl pyruvate, and methyl-3-methoxypropionate. Specific examples of the aromatic hydrocarbon solvent include mesitylene, toluene, and xylene.

[0140] Among the above solvents, PGMEA and cyclopentanone are more preferable, as the use of these solvents can improve the solubility of the polymer A (polynorbornene) and the polyimide (polyimide).

[0141] (surfactant) The photosensitive resin composition according to this embodiment may further contain a surfactant.

[0142] The surfactant is not limited, and specific examples thereof include polyoxyethylene alkyl ethers such as polyoxyethylene lauryl ether, polyoxyethylene stearyl ether, and polyoxyethylene oleyl ether; polyoxyethylene aryl ethers such as polyoxyethylene octylphenyl ether and polyoxyethylene nonylphenyl ether; nonionic surfactants such as polyoxyethylene dialkyl esters such as polyoxyethylene dilaurate and polyoxyethylene distearate; F-TOP EF301, F-TOP EF303, F-TOP EF352 (manufactured by Shin Akita Kasei Co., Ltd.), Megafac F171, Megafac F172, Megafac F173, Megafac F177, Megafac F444, Megafac F470, Examples of commercially available fluorine-based surfactants include those sold under the names Megafac F471, Megafac F475, Megafac F482, and Megafac F477 (manufactured by DIC Corporation), Fluorad FC-430, Fluorad FC-431, Novec FC4430, and Novec FC4432 (manufactured by 3M Japan Co., Ltd.), Surflon S-381, Surflon S-382, Surflon S-383, Surflon S-393, Surflon SC-101, Surflon SC-102, Surflon SC-103, Surflon SC-104, Surflon SC-105, and Surflon SC-106 (manufactured by AGC Seimi Chemical Co., Ltd.); organosiloxane copolymer KP341 (manufactured by Shin-Etsu Chemical Co., Ltd.); and (meth)acrylic acid copolymer Polyflow No. 57 and 95 (manufactured by Kyoeisha Chemical Co., Ltd.).

[0143] Among these, it is preferable to use a fluorine-based surfactant having a perfluoroalkyl group. As the fluorine-based surfactant having a perfluoroalkyl group, it is preferable to use one or more selected from the above specific examples: Megafac F171, Megafac F173, Megafac F444, Megafac F470, Megafac F471, Megafac F475, Megafac F482, Megafac F477 (manufactured by DIC Corporation), Surflon S-381, Surflon S-383, Surflon S-393 (manufactured by AGC Seimi Chemical Co., Ltd.), Novec FC4430 and Novec FC4432 (manufactured by 3M Japan Ltd.).

[0144] Silicone surfactants (such as polyether-modified dimethylsiloxanes) can also be preferably used as surfactants. Specific examples of silicone surfactants include the SH series, SD series, and ST series from Dow Corning Toray Co., Ltd., the BYK series from BYK Japan Co., Ltd., the KP series from Shin-Etsu Chemical Co., Ltd., the DISSFORM (registered trademark) series from NOF Corporation, and the TSF series from Toshiba Silicones.

[0145] The upper limit of the surfactant content in the photosensitive resin composition is preferably 1% by mass (10,000 ppm) or less, more preferably 0.5% by mass (5,000 ppm) or less, and even more preferably 0.1% by mass (1,000 ppm) or less, based on the total amount of the photosensitive resin composition (including the solvent).

[0146] Furthermore, there is no particular lower limit for the content of the surfactant in the photosensitive resin composition, but from the viewpoint of obtaining a sufficient effect of the surfactant, the content is, for example, 0.001 mass % (10 ppm) or more of the entire photosensitive resin composition (including the solvent). By appropriately adjusting the amount of surfactant, it is possible to improve the coatability and the uniformity of the coating film while maintaining other performance properties.

[0147] (antioxidant) The photosensitive resin composition according to this embodiment may further contain an antioxidant. As the antioxidant, one or more selected from phenol-based antioxidants, phosphorus-based antioxidants, and thioether-based antioxidants can be used. The antioxidant can suppress oxidation of the resin film formed from the photosensitive resin composition.

[0148] Phenolic antioxidants include pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 3,9-bis{2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}2,4,8,10-tetraoxaspiro[5,5]undecane, octadecyl-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate, and 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]. ester], 1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 2,6-di-t-butyl-4-methylphenol, 2,6-di-t-butyl-4-ethylphenol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3,5-di-t-butyl-4-hydroxyphenyl)propionate, distearyl (3,5-di-t-butyl-4-hydroxybenzyl)phosphonate, thiodiethylene glycol bis[(3,5-di-t-butyl-4-hydroxyphenyl)propionate] t)], 4,4'-thiobis(6-t-butyl-m-cresol), 2-octylthio-4,6-di(3,5-di-t-butyl-4-hydroxyphenoxy)-s-triazine, 2,2'-methylenebis(4-methyl-6-t-butyl-6-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), bis[3,3-bis(4-hydroxy-3-t-butylphenyl)butylic acid]glycol ester, 4,4'-butylidenebis(6-t-butyl-m-cresol), 2,2'-ethylidenebis(4,6-di- t-butylphenol), 2,2'-ethylidenebis(4-s-butyl-6-t-butylphenol), 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, bis[2-t-butyl-4-methyl-6-(2-hydroxy-3-t-butyl-5-methylbenzyl)phenyl]terephthalate, 1,3,5-tris(2,6-dimethyl-3-hydroxy-4-t-butylbenzyl)isocyanurate, 1,3,5-tris(3,5-di-t-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, 1,3,5-Tris[(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxyethyl]isocyanurate, tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate]methane, 2-t-butyl-4-methyl-6-(2-acryloyloxy-3-t-butyl-5-methylbenzyl)phenol, 3,9-bis(1,1-dimethyl-2-hydroxyethyl)-2,4-8,10-tetraoxaspiro[5,5] Undecane-bis[β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate], triethylene glycol bis[β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate], 1,1'-bis(4-hydroxyphenyl)cyclohexane, 2,2'-methylenebis(4-methyl-6-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 2,2'-methylenebis(6-(1 -methylcyclohexyl)-4-methylphenol), 4,4'-butylidenebis(3-methyl-6-t-butylphenol), 3,9-bis(2-(3-t-butyl-4-hydroxy-5-methylphenylpropionyloxy)1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro(5,5)undecane, 4,4'-thiobis(3-methyl-6-t-butylphenol), 4,4'-bis(3,5-di-t-butyl-4-hydroxybenzyl)sa sulfide, 4,4'-thiobis(6-t-butyl-2-methylphenol), 2,5-di-t-butylhydroquinone, 2,5-di-t-amylhydroquinone, 2-t-butyl-6-(3-t-butyl-2-hydroxy-5-methylbenzyl)-4-methylphenyl acrylate, 2,4-dimethyl-6-(1-methylcyclohexyl) styrenated phenol, 2,4-bis((octylthio)methyl)-5-methylphenol, etc.

[0149] Phosphorus-based antioxidants include bis(2,6-di-t-butyl-4-methylphenyl)pentaerythritol diphosphite, tris(2,4-di-t-butylphenyl phosphite), tetrakis(2,4-di-t-butyl-5-methylphenyl)-4,4'-biphenylene diphosphonite, 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, bis-(2,6-dicumylphenyl)pentaerythritol diphosphite, 2,2-methylenebi Examples include bis(4,6-di-t-butylphenyl)octyl phosphite, tris(mixed mono- and di-nonylphenyl phosphite), bis(2,4-di-t-butylphenyl)pentaerythritol diphosphite, bis(2,6-di-t-butyl-4-methoxycarbonylethyl-phenyl)pentaerythritol diphosphite, and bis(2,6-di-t-butyl-4-octadecyloxycarbonylethylphenyl)pentaerythritol diphosphite.

[0150] Examples of thioether antioxidants include dilauryl-3,3'-thiodipropionate, bis(2-methyl-4-(3-n-dodecyl)thiopropionyloxy)-5-t-butylphenyl)sulfide, distearyl-3,3'-thiodipropionate, and pentaerythritol-tetrakis(3-lauryl)thiopropionate.

[0151] (Preparation of Photosensitive Resin Composition) The method for preparing the photosensitive resin composition in this embodiment is not limited, and any known method can be used depending on the components contained in the photosensitive resin composition. For example, the composition can be prepared by mixing and dissolving the above components in a solvent.

[0152] (Photosensitive resin composition, cured film) The photosensitive resin composition according to this embodiment is used by applying the photosensitive resin composition to a surface containing a metal such as Al or Cu, then pre-baking to dry the composition and form a resin film, then exposing and developing the composition to pattern the resin film into a desired shape, and then post-baking the resin film to harden it and form a hardened film.

[0153] When forming the permanent film, the pre-baking conditions can be, for example, a heat treatment at a temperature of 50° C. to 150° C. for 30 seconds to 1 hour, and the post-baking conditions can be, for example, a heat treatment at a temperature of 150° C. to 250° C. for 30 minutes to 10 hours.

[0154] The viscosity of the photosensitive resin composition according to this embodiment can be appropriately set depending on the desired thickness of the resin film. The viscosity of the photosensitive resin composition can be adjusted by adding a solvent. During the adjustment, it is necessary to keep the contents of the urea compound and the non-cyclic amide compound in the solvent constant.

[0155] The upper limit of the viscosity of the photosensitive resin composition according to this embodiment may be, for example, 5000 mPa·s or less, 4000 mPa·s or less, or 3000 mPa·s or less. The lower limit of the viscosity of the photosensitive resin composition according to this embodiment may be, for example, 10 mPa·s or more, or 50 mPa·s or more, depending on the desired thickness of the resin film.

[0156] The film obtained from the photosensitive resin composition of this embodiment has a maximum elongation of 10 to 200%, preferably 20 to 150%, and an average elongation of 1 to 150%, preferably 2 to 120%, as measured by a tensile test using a Tensilon tester. The film obtained from the photosensitive resin composition of this embodiment can have a tensile strength of 30 to 300 MPa, preferably 50 to 200 MPa.

[0157] As described above, the photosensitive resin composition of the present embodiment can provide a cured product such as a film having excellent mechanical strength. Although the reason for this is not clear, it is presumed to be due to the excellent properties of the rigid polyimide of the present invention.

[0158] A film made of the photosensitive resin composition of this embodiment has an excellent low dielectric loss tangent, and the dielectric loss tangent (tan δ) measured at a frequency of 10 GHz can be 0.008 or less, preferably 0.007 or less, and more preferably 0.006 or less.

[0159] A film made of the photosensitive resin composition of this embodiment has reduced cure shrinkage and can have a coefficient of linear thermal expansion (CTE) of 200 ppm / °C or less, preferably 150 ppm / °C or less.

[0160] (Application) The photosensitive resin composition (negative photosensitive resin composition) of this embodiment is used to form resin films for semiconductor devices, such as permanent films and resists. Among these, it is preferably used in applications using permanent films, from the viewpoint of achieving a good balance between improving the adhesion between the photosensitive resin composition and an Al pad after pre-baking and suppressing the generation of residues of the photosensitive resin composition during development, improving the adhesion between a cured film of the photosensitive resin composition and metal after post-baking, and also improving the chemical resistance of the photosensitive resin composition after post-baking.

[0161] In this embodiment, the resin film includes a cured film of a photosensitive resin composition. That is, the resin film according to this embodiment is formed by curing a photosensitive resin composition.

[0162] The permanent film is a resin film obtained by pre-baking, exposing, and developing a photosensitive resin composition, patterning it into a desired shape, and then post-baking it to harden it. The permanent film can be used as a protective film, an interlayer film, a dam material, etc. in semiconductor devices.

[0163] The resist is composed of a resin film obtained by applying a photosensitive resin composition to an object to be masked by the resist by a method such as spin coating, roll coating, flow coating, dip coating, spray coating, or doctor coating, and then removing the solvent from the photosensitive resin composition. An example of the semiconductor device according to this embodiment is shown in FIG.

[0164] The semiconductor device 100 according to this embodiment can be a semiconductor device including the resin film. Specifically, in the semiconductor device 100, one or more of the group consisting of the passivation film 32, the insulating layer 42, and the insulating layer 44 can be a resin film including the cured product of this embodiment. Here, the resin film is preferably a permanent film as described above.

[0165] The semiconductor device 100 is, for example, a semiconductor chip. In this case, the semiconductor device 100 is mounted on a wiring board via bumps 52 to obtain a semiconductor package.

[0166] The semiconductor device 100 includes a semiconductor substrate on which semiconductor elements such as transistors are provided, and a multilayer wiring layer (not shown) provided on the semiconductor substrate. The uppermost layer of the multilayer wiring layer includes an interlayer insulating film 30 and a top-layer wiring 34 provided on the interlayer insulating film 30. The top-layer wiring 34 is made of, for example, aluminum (Al). A passivation film 32 is provided on the interlayer insulating film 30 and the top-layer wiring 34. An opening is provided in a part of the passivation film 32, exposing the top-layer wiring 34.

[0167] A redistribution layer 40 is provided on the passivation film 32. The redistribution layer 40 has an insulating layer 42 provided on the passivation film 32, a redistribution line 46 provided on the insulating layer 42, and an insulating layer 44 provided on the insulating layer 42 and the redistribution line 46. An opening connected to the top-layer wiring 34 is formed in the insulating layer 42. The redistribution line 46 is formed on the insulating layer 42 and in the opening provided in the insulating layer 42, and is connected to the top-layer wiring 34. An opening connected to the redistribution line 46 is formed in the insulating layer 44.

[0168] Bumps 52 are formed in the openings provided in the insulating layer 44 via, for example, an under bump metallurgy (UBM) layer 50. The semiconductor device 100 is connected to a wiring board or the like via the bumps 52, for example. Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various configurations other than those described above can be adopted as long as they do not impair the effects of the present invention. [Example]

[0169] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0170] [Synthesis Example 1] (Synthesis of 1-[4-(5-2-norbornyl)butyl]-3,4-dimethyl-pyrrole-2,5-dione (NBBuDMMI)) In a 500 mL round-bottom flask, dimethylmaleic anhydride (42.6 g, 0.34 mol) was dissolved in toluene (300 mL) at room temperature. The solution was placed under a nitrogen atmosphere to remove oxygen. The reaction flask was placed in an ice bath to prevent excessive heating from the exothermic reaction. Once the dimethylmaleic anhydride was dissolved, a dropping funnel containing 5-norbornene-2-butylamine (49.6 g, 0.30 mol) was attached, and the norbornene compound was added dropwise to the reaction flask over a 3-hour period. The dropping funnel was removed, and the flask was fitted with a Dean-Stark tube and reflux condenser. The solution was heated to reflux in an oil bath set at 125 °C, and the reaction was stirred at that temperature for 18 hours. Approximately 6 mL of water was collected in the Dean-Stark tube during this time. The flask was removed from the oil bath and allowed to cool to room temperature. The toluene solvent was removed using an evaporator, yielding a yellow oil. The crude product was loaded onto a flash chromatography column (250 g of silica gel) and eluted with 1.7 L of a solvent mixture of cyclohexane and ethyl acetate (95 / 5 wt ratio). The elution solvent was removed using an evaporator, and the residue was then dried under vacuum at 45°C for 18 hours to obtain 80.4 g (92.7% yield) of the desired product. The reaction scheme is shown below.

[0171] [ka]

[0172] [Hansen solubility parameters of solvents] The Hansen solubility parameters of solvents and mixed solvents were obtained from the database of the computer software HSPiP or by inputting the molecular structure into the DIY program of the computer software HSPiP. For mixed solvents, the solubility parameters were calculated using the following formula: In the equation below, the volume ratio of solvent 1 is represented by a, the Hansen solubility parameter is represented by the dispersion term (δD1), polarization term (δP1), and hydrogen bonding term (δH1), the volume ratio of solvent 2 is represented by b, and the Hansen solubility parameter is represented by the dispersion term (δD2), polarization term (δP2), and hydrogen bonding term (δH2). Table 1 shows the dispersion term (δD), polarization term (δP), and hydrogen bond term (δH) of the polymer (pNBBuDMMI), solvent, and mixed solvent, and Table 2 shows the Hansen distance Ra between the polymer (pNBBuDMMI) and the mixed solvent.

[0173]

number

[0174] [Hansen solubility parameters for polynorbornene (pNBBuDMMI)] The Hansen solubility parameter a of polynorbornene was measured by the following method. The polynorbornene used in the following measurements was the homopolymer of NBBuDMMI obtained in Synthesis Example 1. The dispersion parameter (δD), polarization parameter (δP), and hydrogen bond parameter (δH) of polynorbornene are not affected by the weight-average molecular weight of the polynorbornene. [method] To a 5 ml glass container, add 0.05 g of polynorbornene and 1 ml of any solvent selected from the evaluation solvents listed below, and after stirring for 1 hour with a mix rotor, visually evaluate the dispersibility using the following three-point scale. All evaluation solvents and the evaluation results for dispersibility in those solvents are entered into the Sphere program of the computer software HSPiP (version 5.2.02), and the Hansen solubility parameters are calculated. (Solvent for evaluation) Hexane, cyclohexane, toluene, benzyl benzoate, propylene carbonate, 1-hexene, methyl ethyl ketone, acetone, acetonitrile, ethyl acetate, propylene glycol monomethyl ether acetate, cyclohexanol, isopropyl alcohol, methanol (evaluation) 1: Completely dissolved. 2: Partially dissolves. 6: Does not dissolve.

[0175] As a result of the measurement, the dispersion term (δD) of the Hansen solubility parameter of polynorbornene was 18.9 MPa. 1 / 2 , the polarization term (δP) is 5.5 MPa1 / 2 , the hydrogen bond term (δH) is 7.2 MPa 1 / 2 It was. Table 1 shows the dispersion term (δD), polarization term (δP), and hydrogen bond term (δH) of polynorbornene (pNBBuDMMI) and the solvent, and Table 2 shows the difference between the Hansen solubility parameter a of polynorbornene (pNBBuDMMI) and the Hansen solubility parameter b of the solvent.

[0176] [Table 1]

[0177] [Table 2]

[0178] [Example 1] Synthesis of polynorbornene 1 A suitable reaction vessel equipped with a stirrer and condenser was purged with nitrogen for 1 hour and then charged with 1-[4-(5-2-norbornyl)butyl]-3,4-dimethylpyrrole-2,5-dione (NBBuDMMI) (24.60 g, 90 mmol) and triethylsilane (3.14 g, 27 mmol). Cyclopentyl methyl ether (CPME) (16.04 g) and ethyl acetate (EA) (1.98 g) were added to obtain a reaction solution. The reaction solution was heated to 70 °C with stirring under a nitrogen flow (50 mL / min). A solution of the catalyst (palladium(II)(acetonitrile)bis(triisopropylphosphine)acetate tetrakis(2,3,4,5,6-pentafluorophenyl)borate, Pd-1206) (0.0434 g) and the cocatalyst (N,N-dimethylanilinium tetrakis(pentafluorophenyl)borate, DANFABA) (0.0288 g) in ethyl acetate (EA) (3.37 g) was prepared and added to the reaction solution at a molar ratio of NBBuDMMI:catalyst:cocatalyst = 2500:1:1. Polymerization was then carried out at 70°C for 3 hours, and the reaction was stopped by allowing the mixture to cool. The resulting polymerization solution was diluted with tetrahydrofuran to prepare a diluted solution, which was then added dropwise to a methanol solution to precipitate a white solid. The resulting white solid was collected and vacuum dried at 50°C to obtain 20.02 g of a polymer (polynorbornene 1). The toluene content of Polynorbornene 1 measured by the method described below was below the detection limit.

[0179] [Example 2] Synthesis of polynorbornene 2 Synthesis was performed in the same manner as in Example 1, except that CPME in Example 1 was changed to 4-methyltetrahydropyran (MTHP) under the conditions in Table 3 below. The toluene content of polynorbornene 2 measured by the method described below was below the detection limit.

[0180] [Example 3] Synthesis of polynorbornene 3 Synthesis was performed in the same manner as in Example 1, except that CPME in Example 1 was changed to cyclohexane (CH) under the conditions in Table 3 below. The toluene content of Polynorbornene 3 measured by the method described below was below the detection limit.

[0181] [Example 4] Synthesis of polynorbornene 4 Synthesis was performed in the same manner as in Example 1, except that CPME in Example 1 was changed to methylcyclohexane (MCH) under the conditions in Table 3 below. The toluene content of Polynorbornene 4 measured by the method described below was below the detection limit.

[0182] [Example 5] Synthesis of polynorbornene 5 The synthesis was carried out in the same manner as in Example 1 under the conditions shown in Table 3 below. The toluene content of Polynorbornene 5 measured by the method described below was below the detection limit.

[0183] [Comparative Example 1] Synthesis of polynorbornene 6 Synthesis was performed in the same manner as in Example 1 under the conditions in Table 3 below, except that cyclopentyl methyl ether in Example 1 was changed to toluene (Tol). The toluene content of Polynorbornene 6 measured by the method described below was 350 ppm. The polynorbornenes obtained in all Examples did not contain trifluorotoluene.

[0184] (Weight average molecular weight (Mw) · Number average molecular weight (Mn) · Molecular weight distribution (PDI)) In Synthesis Example 1, the weight average molecular weight (Mw), number average molecular weight (Mn), and molecular weight distribution (PDI: Mw / Mn) are polystyrene-equivalent values ​​obtained from a calibration curve of standard polystyrene (PS) obtained by GPC measurement. The measurement conditions are as follows: Tosoh gel permeation chromatography device HLC-8320GPC Column: Tosoh TSK-GEL Supermultipore HZ-M Detector: RI detector for liquid chromatography Measurement temperature: 40℃ Solvent: THF Sample concentration: 5.0 mg / ml

[0185] (conversion rate) In Examples 1 to 5 and Comparative Example 1, the conversion of NBBuDMMI was determined by sampling the reaction solution before and after polymerization and measuring the samples by gas chromatography (GC). The measurement conditions were as follows: Shimadzu gas chromatography equipment GC-2030 Column: SH-Rxi-1HT Detector: FID Measurement conditions: 210°C (30 minutes) Internal standard: methyl amyl ketone Dilution solvent: mesitylene Sample concentration: 5.0 mg / ml

[0186] (Toluene content) In Examples 1 to 5 and Comparative Example 1, the toluene content was determined by measuring the content of purified polynorbornene by gas chromatography mass spectrometry (GC / MS). The detection limit was approximately 10 ppm or less. Column: F-Lab UA5-30M (0.25 mm x 30 m, film thickness: 250 mm) Carrier gas: He, 1 ml / min Column temperature: 40°C (5 min) → 10°C / min → 300°C (9 min) Detector: MS Inlet temperature: 210℃ Split ratio: 50:1 Sample weight: 2.0 mg Ion source: EI, m / z 25-800

[0187] [Table 3]

[0188] [Synthesis Example 1] (Polyimide synthesis) In the synthesis of the following polyimides, the following compounds were used: 4,4-diamino-3,3-diethyl-5,5-dimethyldiphenylmethane (hereinafter also referred to as MED-J) represented by the following formula [ka]

[0189] 4-[4-(1,3-dioxoisobenzofuran-5-ylcarbonyloxy)-2,3,5-trimethylphenyl]-2,3,6-trimethylphenyl 1,3-dioxoisobenzofuran-5-carboxylate (hereinafter also referred to as TMPBP-TME) represented by the following formula: [ka]

[0190] First, 43.99 g (155.8 mmol) of MED-J and 89.22 g (144.2 mmol) of TMPBP-TME were placed in an appropriately sized reaction vessel equipped with a stirrer and a condenser, followed by the addition of 399.64 g of γ-butyrolactone (GBL). After bubbling nitrogen for 10 minutes, the temperature was raised to 60°C while stirring and the reaction was allowed to proceed for 1 hour. A solution of 8.73g (69.2mmol) of dimethyl maleic anhydride in 26.19g of gamma-butyrolactone was prepared in advance, and this solution was added to the reaction vessel and allowed to react for another 30 minutes. The reaction was then continued for another 3 hours at 175°C, where the diamine and acid anhydride were polymerized and the ends were capped to produce a polymerized solution. The obtained polymerization solution was diluted with tetrahydrofuran to prepare a diluted solution, and then the diluted solution was added dropwise to a methanol solution to precipitate a white solid. The obtained white solid was collected and vacuum dried at a temperature of 80°C to obtain 125.88 g of polyimide. GPC measurement of the polyimide revealed that the weight average molecular weight Mw was 74,000, the polydispersity index (weight average molecular weight Mw / number average molecular weight Mn) was 2.62, and the end-capping rate was 65%. The polyimide obtained contained a repeating unit represented by the following formula in part and had a dimethylmaleimide group at the end. [ka]

[0191] [Example 6] The following photosensitive resin compositions were prepared using the following components: Photosensitizer: 1-chloro-4-propoxythioxanthone (SPEEDCURE CPTX (trade name), manufactured by Lambson, UK) Solvent: Cyclopentanone Adhesion aid: 3-trimethoxysilylpropylsuccinic anhydride (Shin-Etsu Chemical Co., Ltd., product name "X-12-967C") The components listed in Table 4 were mixed to prepare a photosensitive resin composition. The obtained photosensitive resin composition was spin-coated onto the surface of a silicon wafer so that the film thickness after drying would be 10 μm, and after pre-baking at 120°C for 4 minutes, it was irradiated with 1500 mJ / cm 2 using a high-pressure mercury lamp. 2 After that, the film was cured at 200° C. for 120 minutes in a nitrogen atmosphere to prepare a film.

[0192] [Polymer compatibility (compatibility of polynorbornene with polyimide)] The obtained photosensitive resin composition was pre-baked at 120° C. for 4 minutes, and then the surface was visually inspected under a fluorescent lamp to determine whether it was cloudy or not, and evaluated according to the following criteria. 〇: Compatible. ×: Not compatible.

[0193] (Dielectric loss tangent Df) The photosensitive resin composition of Example 6 was applied to a substrate, the coating was dried at 120°C for 10 minutes, exposed to PLA (540 mJ), and cured at 200°C for 2 hours in a nitrogen atmosphere to obtain a film with a thickness of 100 μm. The dielectric loss tangent of the obtained film at 10 GHz was measured using a cavity resonator method.

[0194] [Evaluation of patterning characteristics] It was confirmed in the following manner that the photosensitive resin composition of Example 6 could be sufficiently patterned by exposure and development. The photosensitive resin composition of Example 6 was applied onto an 8-inch silicon wafer using a spin coater. After application, the wafer was prebaked on a hot plate in the atmosphere at 120°C for 4 minutes to obtain a coating film with a thickness of approximately 8.0 µm. The coating was irradiated with i-line through a mask with a 20 μm wide via pattern using an i-line stepper (Nikon Corporation, NSR-4425i). After the exposure, the film was spray-developed for 120 seconds using cyclopentanone as a developer to dissolve and remove the unexposed areas, thereby obtaining a via pattern. The cross section of the obtained via pattern was observed using a benchtop SEM. The width at the midpoint between the bottom surface and the opening of the via pattern was taken as the via width, and was evaluated according to the following criteria. Excellent patterning: 20 μm via pattern opening Poor patterning: 20 μm via pattern does not open The coating film obtained from the photosensitive resin composition of Example 6 had good patterning properties.

[0195] [Table 4] [Explanation of symbols]

[0196] 30 Interlayer insulating film 32 Passivation film 34 Top layer wiring 40 Redistribution layer 42 Insulating layer 44 Insulating layer 46 Rewiring 50 UBM layers 52 Bump 100 Semiconductor device

Claims

1. The method includes a step of polymerizing a norbornene-based compound in a solvent in the presence of a palladium catalyst and a chain transfer agent to obtain polynorbornene, The solvent does not contain toluene and trifluorotoluene or contains toluene and trifluorotoluene at levels below the detection limit in GC / MS measurement, The solvent is substantially one solvent selected from the group consisting of ether solvents, hydrocarbon solvents containing no aromatic ring, and ethyl acetate, or a mixed solvent of two or more solvents; The difference between the Hansen solubility parameter a of the polynorbornene and the Hansen solubility parameter b of the solvent is 8 MPa. １／２ The following is a method for producing polynorbornene.

2. The method for producing polynorbornene according to claim 1 , wherein the norbornene-based compound includes a compound represented by the following general formula (1): 【Chemistry 1】 (In general formula (1), R １ and R ２ each independently represents a hydrogen atom or an alkyl group having 1 to 3 carbon atoms; Q １ represents a single bond or a divalent organic group, G １ , G ２ , and G ３ each independently represents a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 1 to 30 carbon atoms; and m is 0, 1, or 2.

3. 3. The method for producing polynorbornene according to claim 1, wherein the chain transfer agent comprises at least one selected from the group consisting of a compound represented by the following general formula (a), formic acid, and oxalic acid: 【Chemistry 2】 (In general formula (a), R1, R2, and R3 each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.)

4. 4. The method for producing polynorbornene according to claim 3, wherein in general formula (a), R1, R2, and R3 each independently represent an alkyl group having 1 to 3 carbon atoms.

5. The method for producing polynorbornene according to any one of claims 1 to 4, wherein the solvent is a mixed solvent of two or more kinds.

6. The method for producing polynorbornene according to any one of claims 1 to 5, wherein the solvent includes at least one selected from an ether-based solvent and a hydrocarbon-based solvent not containing an aromatic ring.

7. the ether-based solvent includes at least one selected from cyclopentyl methyl ether and methyl tetrahydropyran; The method for producing polynorbornene according to claim 6 , wherein the hydrocarbon solvent not containing an aromatic ring comprises at least one selected from cyclohexane and methylcyclohexane.

8. When the solvent is a mixed solvent of two kinds of solvents, the difference between the Hansen solubility parameter a of the norbornene-based compound and the Hansen solubility parameter c of the mixed solvent of two kinds of solvents is 8 MPa or less. １／２ The method for producing polynorbornene according to any one of claims 1 to 7, wherein the polynorbornene is:

9. The method for producing polynorbornene according to any one of claims 1 to 8, wherein the solvent is a mixed solvent of at least one selected from cyclopentyl methyl ether, methyltetrahydropyran, cyclohexane, and methylcyclohexane with ethyl acetate.

10. The method for producing polynorbornene according to any one of claims 1 to 9, wherein the palladium catalyst is used in an amount of 1 / 5000 mol or more and 1 / 2000 mol or less per 1 mol of the norbornene-based compound.

11. The method for producing polynorbornene according to any one of claims 1 to 9, further comprising a step of mixing the polynorbornene obtained in the polymerization step with a poor solvent for the polynorbornene to reprecipitate powdery polynorbornene.

12. The method for producing polynorbornene according to claim 11, further comprising a step of diluting the polynorbornene obtained in the polymerization step before the reprecipitation step.

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