JP5576181B2 - Photosensitive resin composition and photosensitive film using the same - Google Patents

Description

  The present invention relates to a photosensitive resin composition used for forming a protective layer on a flexible wiring board and a circuit board used for operation panels of various electronic devices in the field of electronics, and a photosensitive film using the same.

  In recent years, a film-like printed board called a flexible printed board (hereinafter referred to as “FPC”) has gained popularity. This FPC has a structure including a coverlay made of a polyimide film or the like on a wiring-processed copper clad laminate (FCCL: Flexible Cupper Laminate). Used in devices such as digital cameras. Since FPC maintains its function even when bent, it has become an indispensable material for reducing the size and weight of equipment. Particularly in recent years, electronic devices represented by notebook computers have been reduced in size and weight. By adopting FPC for such products, the size and weight of the devices are reduced, the product cost is reduced, and the design is reduced. Contributes to simplification.

  In order to perform fine processing by lithography for miniaturization and thinning of FPC, development of a photosensitive coverlay has been energetically performed. Among these, a photosensitive cover lay using a polyimide precursor is expected as an excellent cover lay from the viewpoint of bending resistance derived from polyimide, heat resistance, and electrical insulation.

  In conventional screen printing, the solvent removal process and double-sided processing require two processes, and the resolution of screen printing is low. From the viewpoint of industrial process and resolution, the photosensitive resin composition is used as a dry film. It is hoped that

  As a photosensitive resin composition for solving this, a photosensitive resin composition containing a polyimide precursor having both a polyamic acid structure and a polyimide structure, and a negative photosensitive resin composition in which an exposed portion is insoluble are proposed. (See Patent Document 1). However, in the photosensitive resin composition described in Patent Document 1, since the polyimide precursor has an aliphatic diamine component in the polyamic acid structure, the molecular weight of the polyimide precursor in the baking (heat drying) step in dry film preparation When the photosensitive dry film obtained by reducing the toughness of the film is bent, the photosensitive layer is broken. In addition, when the molecular weight of the polyimide precursor is reduced, in the development process using an alkaline aqueous solution at the time of pattern formation by lithography, the development time becomes unstable, the residual film ratio is reduced, the pattern shape is distorted, etc. There was a tendency for developability to decrease.

  Further, in the FPC manufacturing process, in the imidization process in which the polyimide precursor is converted to polyimide, the FPC may be warped due to the stress resulting from the solvent removal or the ring closure reaction accompanying the imidization of the polyimide precursor. When warpage occurs in the FPC, problems such as poor adhesion between the FCCL and the coverlay and an increase in driving power of an electronic device equipped with the FPC arise. For this reason, it is required to improve the warpage of the FPC having a coverlay on the copper wiring.

  Furthermore, FPC is required to have insulation reliability under high temperature and high humidity for interposer applications. As a photosensitive resin composition with improved insulation reliability, a photosensitive resin composition in which a polyimide and a metal chelate compound are combined has been proposed, but the insulation reliability under high temperature and high humidity is not sufficient (patent) Reference 2).

  In addition, the coverlay is required to exhibit flame retardancy in a flame retardancy test represented by the UL standard VTM test. In order to express the flame retardancy of the coverlay, a coverlay blended with a halogen compound is used. However, from the viewpoint of environmental conservation and biotoxicity, it is desired that non-halogen and flame retardancy of coverlays be expressed.

JP 2006-321924 A JP-A-5-301959

  The present invention has been made in view of the above point, and is a photosensitive resin composition capable of realizing an FPC coverlay having high developability and bendability and excellent insulation reliability, and photosensitivity using the same. The object is to provide a film.

  As a result of intensive studies, the inventors have a polyamic acid structure and a polyimide structure as repeating structural units, respectively, a polyimide precursor in which a diamine having a specific structure is selectively introduced into the polyimide structure, a specific chelating agent, The present inventors have found that a photosensitive resin composition containing the above and a photosensitive film using the same solve the above problems, and have completed the present invention. That is, the present invention is as follows.

（式（１）中、Ｒ_１は炭素数が１〜３０の４価の有機基であり、それぞれ同じであっても異なっていてもよい。Ｒ_２は炭素数が１〜３０の２価の有機基であり、Ｒ_３は炭素数が１〜３０の１価の有機基であり、それぞれ同じであっても異なっていてもよい。ｎは１以上３０以下の整数を表す。）

（式（２）中、Ｒ_４は炭素数が１〜８０の２価の有機基である。Ｒ_５は炭素数が１〜３０の４価の有機基であり、それぞれ同じであっても異なっていてもよい。） The photosensitive resin composition of the present invention includes a polyimide precursor having a polyimide structure represented by the following general formula (1) and a polyamic acid structure represented by the following general formula (2) as repeating structural units, and a chelate. And 0.1 to 25 parts by mass of the chelating agent with respect to 100 parts by mass of the polyimide precursor.

(In Formula (1), R ₁ is a tetravalent organic group having 1 to 30 carbon atoms, and may be the same or different. R ₂ is a divalent organic group having 1 to 30 carbon atoms. And R ₃ is a monovalent organic group having 1 to 30 carbon atoms, which may be the same or different, and n represents an integer of 1 to 30.)

(In Formula (2), R ₄ is a divalent organic group having 1 to 80 carbon atoms. R ₅ is a tetravalent organic group having 1 to 30 carbon atoms, and each is the same or different. May be.)

  In the photosensitive resin composition of the present invention, the chelating agent is preferably dissolved in an amount of 0.1% by weight or more in any of gamma butyrolactone, methyl ethyl ketone, and N-methyl-2-pyrrolidone.

  The photosensitive resin composition of the present invention preferably contains at least two (meth) acrylate compounds having a photopolymerizable unsaturated double bond and a photopolymerization initiator.

  In the photosensitive resin composition of the present invention, the (meth) acrylate compound having at least two or more photopolymerizable unsaturated double bonds includes a compound having two double bonds and 3 double bonds. It is preferable to include both compounds having at least two.

  The photosensitive resin composition of the present invention preferably contains a phosphorus compound.

  In the photosensitive resin composition of the present invention, the phosphorus compound preferably has at least one structure selected from the group consisting of a phosphate ester structure and a phosphazene structure.

  The photosensitive resin composition of the present invention preferably contains a thermally reactive resin.

  The photosensitive film of the present invention is obtained by applying the photosensitive resin composition to a substrate.

  The laminated film of the present invention comprises a carrier film and the photosensitive film provided on the carrier film.

  The laminated film of the present invention preferably comprises a cover film formed on the photosensitive film.

  The printed wiring board of the present invention comprises a base material having wiring, and a cover lay provided to cover the base material and configured from the laminated film.

  The printed wiring board of the present invention comprises a base material having wiring and a cover lay composed of the laminated film provided so as to cover the base material.

  ADVANTAGE OF THE INVENTION According to this invention, the photosensitive resin composition which can implement | achieve the coverlay of FPC which is high in developability and bendability, and is excellent in insulation reliability, and the photosensitive film using the same can be provided.

In order to carry out the present invention, a specific description will be given below.
(A) Polyimide precursor The polyimide precursor has a polyimide structure represented by the following general formula (1) and a polyamic acid structure represented by the following general formula (2) as repeating structural units.

（式（１）中、Ｒ_１は炭素数が１〜３０の４価の有機基であり、それぞれ同じであっても異なっていてもよい。Ｒ_２は炭素数が１〜３０の２価の有機基であり、Ｒ_３は炭素数が１〜３０の１価の有機基であり、それぞれ同じであっても異なっていてもよい。ｎは１以上３０以下の整数を表す。）

(In Formula (1), R ₁ is a tetravalent organic group having 1 to 30 carbon atoms, and may be the same or different. R ₂ is a divalent organic group having 1 to 30 carbon atoms. And R ₃ is a monovalent organic group having 1 to 30 carbon atoms, which may be the same or different, and n represents an integer of 1 to 30.)

（式（２）中、Ｒ_４は炭素数が１〜８０の２価の有機基である。Ｒ_５は炭素数が１〜３０の４価の有機基であり、それぞれ同じであっても異なっていてもよい。）

(In Formula (2), R ₄ is a divalent organic group having 1 to 80 carbon atoms. R ₅ is a tetravalent organic group having 1 to 30 carbon atoms, and each is the same or different. May be.)

  Since the polyimide precursor has the polyimide structure represented by the general formula (1), the insulation reliability is improved by the water repellent effect of Si atoms in the polyimide structure. The polyimide precursor which has a polyimide structure represented by the said General formula (1) is synthesize | combined using diamine, such as silicone diamine (KF-8010), for example.

  Furthermore, a polyimide precursor is further excellent in insulation reliability by including 20 mass% or more and 80 mass% or less of a diamine component in the polyimide structure represented by the said General formula (1). If the diamine component is 80% by mass or less, the developability is excellent. In addition, the polyimide precursor is preferable since the storage stability of the molecular weight is improved by including a diamine component in the polyimide structure of the above general formula (1).

  The polyimide precursor is synthesized by reacting acid dianhydride with diamine. Specific examples of the acid dianhydride include pyromellitic anhydride, oxydiphthalic dianhydride (hereinafter abbreviated as “ODPA”), biphenyl-3,3 ′, 4,4′-tetracarboxylic dianhydride. (Hereinafter abbreviated as BPDA), benzophenone-3,3 ′, 4,4′-tetracarboxylic dianhydride, diphenylsulfone-3,3 ′, 4,4′-tetracarboxylic dianhydride, 4, 4 ′-(2,2-hexafluoroisopropylidene) diphthalic dianhydride, meta-terphenyl-3,3 ′, 4,4′-tetracarboxylic dianhydride, 1,2,4,5-cyclohexane Tetracarboxylic dianhydride, bicyclo [2,2,2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, cyclobutane-1,2,3,4-tetracarboxylic dianhydride Anhydride, 1-Carbox Methyl-2,3,5-cyclopentatricarboxylic acid-2,6: 3,5-dianhydride, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3,4-tetrahydro Naphthalene-1,2-dicarboxylic anhydride, 5- (2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, ethylene glycol bis (trimellitic acid monoester Acid anhydride) (hereinafter abbreviated as “TMEG”), p-phenylenebis (trimellitic acid monoester acid anhydride), ethylenebis (trimellitate) dianhydride, and the like.

  Of these, ODPA, TMEG, BPDA, p-phenylenebis (trimellitic acid monoester anhydride), 4- (2,5-dioxo) from the viewpoint of solvent solubility and low Tg of the polyimide precursor Tetrahydrofuran-3-yl) -1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic anhydride, 5- (2,5-dioxotetrahydrofuryl) -3-methyl-3-cyclohexene-1, 2-dicarboxylic acid anhydride and ethylene bis (trimellitate) dianhydride are preferred. Here, the solvent solubility means that the polyimide has a property of being dissolved in a known organic solvent at a concentration of 5% by mass or more.

  As the diamine, 3,3′-dicarboxy-4,4′-diaminodiphenylmethane, 3,5-diaminobenzoic acid, 1,5-bis (4-aminophenoxy) alkane, polytetramethylene oxide-di-p- Aminobenzoate, 1,2-diamino-4-hydroxybenzene, 1,3-diamino-5-hydroxybenzene, 1,3-diamino-4-hydroxybenzene, 1,4-diamino-6-hydroxybenzene, 1,5 -Diamino-6-hydroxybenzene, 1,3-diamino-4,6-dihydroxybenzene, 1,2-diamino-3,5-dihydroxybenzene, 4- (3,5-diaminophenoxy) phenol, 3- (3 , 5-Diaminophenoxy) phenol, 2- (3,5-diaminophenoxy) phenol, 3,3′-dihydride Xy-4,4′-diaminobiphenyl, 3,3′-diamino-4,4′-dihydroxybiphenyl, 2,2-bis (4-hydroxy-3-aminophenyl) propane, 2,2-bis (4- Hydroxy-3-aminophenyl) hexafluoropropane, bis (4-hydroxy-3-aminophenyl) ketone, bis (4-hydroxy-3-aminophenyl) sulfide, bis (4-hydroxy-3-aminophenyl) ether, Bis (4-hydroxy-3-aminophenyl) sulfone, bis (4-hydroxy-3-aminophenyl) methane, 4-[(2,4-diamino-5-pyrimidinyl) methyl] phenol, p- (3,6 -Diamino-s-triazin-2-yl) phenol, bis (4-hydroxy-3-aminophenyl) difluorometa 2,2-bis (4-amino-3-hydroxyphenyl) propane, 2,2-bis (4-amino-3-hydroxyphenyl) hexafluoropropane, bis (4-amino-3-hydroxyphenyl) ketone, Bis (4-amino-3-hydroxyphenyl) sulfide, bis (4-amino-3-hydroxyphenyl) ether, bis (4-amino-3-hydroxyphenyl) sulfone, bis (4-amino-3-hydroxyphenyl) Methane, bis (4-amino-3-hydroxyphenyl) difluoromethane, 1, n-bis (4-aminophenoxy) alkane, 1,4-diaminobenzene, 1,3-diaminobenzene, 2,4-diaminotoluene, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenyl ether, 3,4′-dia Minodiphenyl ether, 3,3′-dimethyl-4,4′-diaminobiphenyl, 2,2′-dimethyl-4,4′-diaminobiphenyl, 2,2′-bis (trifluoromethyl) -4,4′- Diaminobiphenyl, 3,7-diamino-dimethyldibenzothiophene-5,5-dioxide, 4,4′-diaminobenzophenone, 3,3′-diaminobenzophenone, 4,4′-bis (4-aminophenyl) sulfide, 4 , 4′-diaminobenzanilide, 1,3-bis (4-aminophenoxy) -2,2-dimethylpropane, 1,2-bis [2- (4-aminophenoxy) ethoxy] ethane, 9,9-bis (4-aminophenyl) fluorene, 5-amino-1- (4-aminomethyl) -1,3,3-trimethylindane, 1,4-bis (4- Minophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,3-bis (3-aminophenoxy) benzene (hereinafter abbreviated as APB-N), 4,4′-bis (4-amino) Phenoxy) biphenyl, 4,4′-bis (3-aminophenoxy) biphenyl, 2,2-bis (4-aminophenoxyphenyl) propane, bis [4- (4-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy) phenyl] sulfone, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 1,5-bis (4-aminophenoxy) pentane, 1-amino-3-amino Methyl-3,5,5-trimethylcyclohexane, 3,3′-diaminodiphenylsulfone, 1,8-diamino-3,6-di Polyoxyethylene diamine compounds such as xyloctane, polyoxyalkylene diamine compounds such as Huntsman's Jeffamine EDR-148 and EDR-176, and polyoxypropylenes such as Jeffamine D-230, D-400, D-2000 and D-4000 Examples thereof include diamine compounds, compounds having different oxyalkylene groups such as HK-511, ED-600, ED-900, ED-2003, and XTJ-542.

  Among these, APB-N, 1,4-bis (4-aminophenoxy) benzene, 3,3′-diaminodiphenylsulfone, 3,4′- from the viewpoints of Tg control and developability of the alkali-soluble resin. Diaminodiphenyl ether is preferred, and a diamine having an oxyalkylene group and / or a diamine having a siloxane structure is preferred from the viewpoint of reducing the warpage of FPC after polyimide baking.

  The end of the main chain of the polyimide precursor is not particularly limited as long as it does not affect the performance. In addition, the terminal end of the main chain of the polyimide precursor may be an acid dianhydride or a terminal structure derived from a diamine used for producing the polyimide precursor, or a structure in which the terminal is sealed with another acid anhydride, an amine compound, or the like. But you can. For terminal sealing, for example, maleic anhydride is used.

  The weight average molecular weight of the polyimide precursor is preferably 1000 or more and 1000000 or less. Here, the weight average molecular weight refers to a molecular weight measured by gel permeation chromatography using polystyrene having a known weight average molecular weight as a standard. The weight average molecular weight is preferably 1000 or more from the viewpoint of the strength of the polyimide film, and preferably 1000000 or less from the viewpoint of the viscosity and moldability of the polyimide-containing resin composition. The weight average molecular weight is more preferably from 5,000 to 500,000, particularly preferably from 10,000 to 300,000, and most preferably from 25,000 to 50,000.

  A polyimide precursor having a polyimide structure and a polyamic acid structure as repeating units, respectively, is a step of reacting acid dianhydride and diamine in a non-equal molar amount to synthesize a first-stage polyimide site (step 1), followed by 2 It can be produced by a step of synthesizing the polyamic acid at the stage (Step 2). Hereinafter, each process will be described.

(Process 1)
The process of synthesizing the first-stage polyimide site will be described. The step of synthesizing the first-stage polyimide site is not particularly limited as long as it is a polyimide production method, and a known polyimide production method can be applied. More specifically, it is obtained by the following production method. First, diamine is dissolved and / or dispersed in a reaction solvent, and acid dianhydride powder is added thereto. Next, a solvent that is azeotroped with water is added, and the mixture is heated and stirred for 0.5 to 96 hours, preferably 0.5 to 30 hours while azeotropically removing the by-product water using a mechanical stirrer. In this case, the monomer concentration is 0.5% by mass or more and 95% by mass or less, preferably 1% by mass or more and 90% by mass or less.

  When synthesizing a polyimide site, a known imidation catalyst may be added to imidize or may be imidized without a catalyst. The imidation catalyst is not particularly limited, but an acid anhydride such as acetic anhydride, a lactone compound such as γ-valerolactone, γ-butyrolactone, γ-tetronic acid, γ-phthalide, γ-coumarin, and γ-phthalido acid. , Tertiary amines such as pyridine, quinoline, N-methylmorpholine, triethylamine, and the like. Moreover, 1 type or 2 or more types of mixtures may be sufficient as needed. Among these, a mixed system of γ-valerolactone and pyridine and non-catalyst are particularly preferable from the viewpoint of high reactivity and influence on the next reaction.

  The amount of the imidization catalyst added is preferably 50 parts by mass or less, and more preferably 30 parts by mass or less when the polyamic acid is 100 parts by mass.

  The reaction solvent used in the production of the first-stage polyimide moiety includes 2 or more carbon atoms such as dimethyl ether, diethyl ether, methyl ethyl ether, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether. An ether compound having 9 or less carbon atoms; a ketone compound having 2 to 6 carbon atoms such as acetone and methyl ethyl ketone; and 5 or more carbon atoms such as normal pentane, cyclopentane, normal hexane, cyclohexane, methylcyclohexane, and decalin 10 or less saturated hydrocarbon compounds; aromatic hydrocarbon compounds having 6 to 10 carbon atoms such as benzene, toluene, xylene, mesitylene, and tetralin; methyl acetate Ester compounds having 3 to 12 carbon atoms such as ethyl acetate, γ-butyrolactone, methyl benzoate; halogen-containing compounds having 1 to 10 carbon atoms such as chloroform, methylene chloride, and 1,2-dichloroethane A nitrogen-containing compound having 2 to 10 carbon atoms such as acetonitrile, N, N-dimethylformamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone; a sulfur-containing compound such as dimethyl sulfoxide; It is done. These may be one kind or a mixture of two or more kinds as necessary. Particularly preferable solvents include ether compounds having 2 to 9 carbon atoms, ester compounds having 3 to 12 carbon atoms, aromatic hydrocarbon compounds having 6 to 10 carbon atoms, and carbon atoms having 2 to carbon atoms. A nitrogen-containing compound of several tens or less is mentioned. These can be arbitrarily selected in consideration of industrial productivity and influence on the next reaction.

  In the production of the first-stage polyimide site, the reaction temperature is preferably 15 ° C. or higher and 250 ° C. or lower. If it is 15 degreeC or more, reaction will be started, and if it is 250 degrees C or less, there will be no deactivation of a catalyst. Preferably they are 20 degreeC or more and 220 degrees C or less, More preferably, they are 20 degreeC or more and 200 degrees C or less. The reaction time varies depending on the purpose and reaction conditions, but is usually within 96 hours, and particularly preferably in the range of 30 minutes to 30 hours.

(Process 2)
Next, the process for synthesizing the second stage polyamic acid moiety will be described. The synthesis of the polyamic acid moiety in the second step can be carried out by using the polyimide moiety obtained in Step 1 as a starting material and adding diamine and / or acid dianhydride for reaction.

  The reaction temperature for producing the second stage polyamic acid moiety is preferably 0 ° C. or higher and 250 ° C. or lower, more preferably 0 ° C. or higher and 100 ° C. or lower, and particularly preferably 0 ° C. or higher and 80 ° C. or lower.

  The time required for the reaction of the polyamic acid varies depending on the purpose or reaction conditions, but is usually within 96 hours, and particularly preferably 30 minutes to 30 hours.

  As the reaction solvent, the same solvent as used for the production of the polyimide moiety in Step 1 can be used. In that case, the reaction solution of step 1 can be used as it is. Moreover, you may use the solvent different from what was used for manufacture of the polyimide site | part at the process 1.

  Examples of such solvents include ether compounds having 2 to 9 carbon atoms such as dimethyl ether, diethyl ether, methyl ethyl ether, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, and triethylene glycol dimethyl ether; acetone, methyl ethyl ketone, and the like. A ketone compound having 2 to 6 carbon atoms; a saturated hydrocarbon compound having 5 to 10 carbon atoms, such as normal pentane, cyclopentane, normal hexane, cyclohexane, methylcyclohexane, decalin; benzene, toluene, xylene Aromatic hydrocarbon compounds having 6 to 10 carbon atoms such as mesitylene and tetralin; methyl acetate, ethyl acetate, γ-butyrolactone, benzoic acid Ester compounds having 3 to 12 carbon atoms such as chill; halogen-containing compounds having 1 to 10 carbon atoms such as chloroform, methylene chloride and 1,2-dichloroethane; acetonitrile, N, N-dimethylformamide N, N-dimethylacetamide, N-methyl-2-pyrrolidone and other nitrogen-containing compounds having 2 to 10 carbon atoms; sulfur-containing compounds such as dimethyl sulfoxide.

  These may be one kind or a mixture of two or more kinds as necessary. Particularly preferable solvents include ether compounds having 2 to 9 carbon atoms, ester compounds having 3 to 12 carbon atoms, aromatic hydrocarbon compounds having 6 to 10 carbon atoms, and carbon atoms having 2 to carbon atoms. A nitrogen-containing compound of several tens or less is mentioned. These can be arbitrarily selected in consideration of industrial productivity and influence on the next reaction.

  The polyimide precursor after the production may be used as it is dissolved in the reaction solvent, or may be recovered and purified by the following method. Recovery of the polyimide precursor after completion of production can be performed by distilling off the solvent in the reaction solution under reduced pressure.

  Examples of the method for purifying the polyimide precursor include a method of removing insoluble acid dianhydride and diamine in the reaction solution by vacuum filtration, pressure filtration, or the like. In addition, a so-called reprecipitation purification method in which the reaction solution is precipitated by adding it to a poor solvent can be carried out. Further, when a highly pure polyimide precursor is required, an extraction method by a carbon dioxide supercritical method is also possible.

(B) Chelating agent A chelating agent refers to a compound having a multidentate ligand that binds to a metal ion to form a chelating compound. As a chelating agent, for example, ethylenediaminetetraacetic acid, its potassium salt, its sodium salt, its derivative; diethylenetriaminepentaacetic acid, its potassium salt, its sodium salt, its derivative; triethylenetetraminehexaacetic acid, its potassium salt, its sodium salt, its Derivatives; hydroxyethylethylenediaminetriacetic acid, potassium salt, sodium salt, derivative thereof; N, N, N ′, N′-tetrakis (2-pyridylmethyl) ethylenediamine; nitrilotriacetic acid, sodium salt, derivative thereof; 3-propanediaminetetraacetic acid, its potassium salt, its sodium salt, its derivative; 1,3-diamino-2-hydroxypropanetetraacetic acid, its potassium salt, its sodium salt, its derivative; hydroxyethyliminodivinegar Its potassium salt, its sodium salt, its derivative; dihydroxyethylglycine, its potassium salt, its sodium salt, its derivative; glycol ether diamine tetraacetic acid, its sodium salt, its derivative; trans-cyclohexanediamine tetraacetic acid, its sodium salt, its Derivatives; Carboxymethyl polyethyleneimine; Hydroxyethylidene diphosphonic acid, its potassium salt, its sodium salt; Nitrilotrismethylene trisphosphonic acid, its potassium salt, its sodium salt; Phosphonobutane tricarboxylic acid; Ethylenediamine (tetramethylenephosphonic acid); 1-hydroxyethane-1,1-diphosphonic acid, its potassium salt, its sodium salt; aminotri (methylenephosphonic acid), its potassium salt, its sodium salt, etc. Examples thereof include organic phosphonic acids and phosphonoalkanetricarboxylic acids. Organic amine salts are also effective in place of the sodium and potassium salts of the chelating agents.

  The photosensitive resin composition according to the present invention contains 0.1 to 25 parts by mass of a chelating agent with respect to 100 parts by mass of the polyimide precursor. If the chelating agent is 0.1 parts by mass or more and 25 parts by mass or less, the insulation reliability is improved.

  In the present invention, by using a chelating agent, it is considered that the insulation reliability is improved because the ionic component can be supplemented. However, by using it together with the polyimide structure represented by the general formula (1), the insulation resistance value Both the insulation durability and the insulation durability increase rapidly. The mechanism is considered to be that by introducing a silicone component (SiO component) into the polymer structure (in the polyimide structure), the water repellency of the photosensitive resin composition increases and the insulation resistance value increases. Furthermore, it is considered that by introducing a chelating agent, the insulation resistance value and the insulation durability rapidly increase due to the synergistic effect of water repellency and supplementation of ionic components.

  From the viewpoint of further improving the insulation reliability (electrical insulation resistance), it is preferable that the chelating agent is dissolved in 0.1% by weight or more in any of γ-butyrolactone, methyl ethyl ketone, and N-methyl-2-pyrrolidone. For example, MZ-2 (manufactured by Kirest), MZ-4A (manufactured by Kirest), N, N, N ', N'-tetrakis (2-pyridylmethyl) ethylenediamine (manufactured by Dojindo Laboratories) can be mentioned.

(C) (Meth) acrylate compound having two or more photopolymerizable unsaturated double bonds The photosensitive resin composition according to the present invention has at least two photopolymerizable unsaturated double bonds. It preferably contains a (meth) acrylate compound and a photopolymerization initiator described later. In the photosensitive resin composition which concerns on this invention, developability improves by including the (meth) acrylate compound which has a 2 or more photopolymerizable unsaturated double bond.

  Examples of the (meth) acrylate compound having two or more photopolymerizable unsaturated double bonds include tricyclodecane dimethylol diacrylate, ethylene oxide (EO) modified bisphenol A dimethacrylate, EO modified hydrogenated bisphenol A diacrylate, 1,6-hexanediol (meth) acrylate, 1,4-cyclohexanediol di (meth) acrylate, polypropylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, 2-di (p-hydroxyphenyl) propanedi ( (Meth) acrylate, glycerol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, polyoxypropyltrimethylolpropane tri (meth) acrylate, polyoxyethyltrimethylo Rupropane tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, trimethylolpropane triglycidyl ether (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate, β-hydroxypropyl-β '-(acryloyloxy)- Examples thereof include propyl phthalate, phenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, and pentaerythritol tri / tetra (meth) acrylate. Among them, from the viewpoint of warping after firing, EO-modified bisphenol A dimethacrylate, EO-modified hydrogenated bisphenol A diacrylate, and pentaerythritol tri / tetra (meth) acrylate are preferable.

  In addition, the (meth) acrylate compound having at least two or more photopolymerizable unsaturated double bonds is a combination of a compound having two double bonds and a compound having three or more double bonds. Preferably there is. The amount of the (meth) acrylate compound having two or more photopolymerizable unsaturated double bonds is from 5 parts by weight to 60 parts by weight from the viewpoint of developability when the amount of the polyimide precursor is 100 parts by weight. Is preferably 10 parts by mass or more and 40 parts by mass or less.

(D) Photopolymerization initiator Examples of the photopolymerization initiator include benzyldimethyl ketals such as 2,2-dimethoxy-1,2-diphenylethane-1-one, benzyldipropyl ketals, benzyldiphenyl ketals, and benzoin. Methyl ethers, benzoin ethyl ether, thioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-isopropylthioxanthone, 2-fluorothioxanthone, 4-fluorothioxanthone 2-chlorothioxanthone, 4-chlorothioxanthone, 1-chloro-4-propoxythioxanthone, benzophenone, 4,4′-bis (dimethylamino) benzophenone [Michler's ketone], 4,4′- Aromatic ketone compounds such as su (diethylamino) benzophenone, 2,2-dimethoxy-2-phenylacetophenone, triarylimidazole dimers such as lophine dimer, acridine compounds such as 9-phenylacridine, α, α-dimethoxy Oxime ester compounds such as α-morpholino-methylthiophenylacetophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, N-aryl-α-amino acid, p-dimethylaminobenzoic acid, p-dimethylaminobenzoic acid, p- Diethylaminobenzoic acid, p-diisopropylaminobenzoic acid, p-benzoic acid ester, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1- [4- (2-Hydro Xyloxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4-[(2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2 Α-hydroxyalkylphenones such as methyl-propan-1-one, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2- (dimethylamino) -2- [ Α-aminoalkylphenones such as (4-methylphenyl) methyl] -1- [4- (4-morpholinyl) phenyl] -1-butanone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis Acylphosphine oxides such as (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 1,2-octyl Tandione 1- [4- (phenylthio) -2- (O-benzoyloxime)], ethanone 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (O Oxime esters such as -acetyloxime). Among these, oxime esters are preferable from the viewpoint of sensitivity.

  When the amount of the polyimide precursor is 100 parts by mass, the amount of the photopolymerization initiator is preferably 0.01 parts by mass or more and 40 parts by mass or less from the viewpoint of sensitivity (photosensitivity) and resolution. 0.5 parts by mass or more and 35 parts by mass or less are more preferable.

(E) Phosphorus compound The photosensitive resin composition preferably contains a phosphorus compound in order to improve flame retardancy. The phosphorus compound is not limited as long as it contains a phosphorus atom in its structure, and among these, a compound having at least one structure selected from the group consisting of a phosphate ester structure and a phosphazene structure is preferable. Examples of such compounds include phosphate ester compounds and phosphazene compounds.

  Examples of phosphoric acid ester compounds include trimethyl phosphate, triethyl phosphate, tributyl phosphate, triisobutyl phosphate, phosphate ester having tris (2-ethylhexyl) phosphate as a substituent, tris (butoxyethyl) phosphate, etc. Phosphorus ester, triphenyl phosphate, tricresyl phosphate, trixylenyl phosphate, resorcinol bis (diphenyl phosphate) and other aromatic organic groups as substituents Examples include acid ester compounds. Among these, tris (butoxyethyl) phosphate and triisobutyl phosphate are preferable from the viewpoint of developability.

  Examples of the phosphazene compound include structures represented by the following general formula (4) and the following general formula (5).

R ₂₀ , R ₂₁ , R ₂₂ , and R ₂₃ in the phosphazene compound represented by the general formula (4) and the general formula (5) are not limited as long as they are organic groups having 1 to 20 carbon atoms. The phosphazene compound is preferable if it has 1 or more carbon atoms, and tends to exhibit flame retardancy, and if it has 20 or less carbon atoms, it tends to be compatible with the polyimide precursor. Among these, from the viewpoint of flame retardancy, a functional group derived from an aromatic compound having 6 to 18 carbon atoms is particularly preferable. As such a functional group, phenyl group, 2-methylphenyl group, 3-methylphenyl group, 4-methylphenyl group, 2-hydroxyphenyl group, 3-hydroxyphenyl group, 4-hydroxyphenyl group, 2-cyanophenyl Group, functional group having a phenyl group such as 3-cyanophenyl group and 4-cyanophenyl group, functional group having a naphthyl group such as 1-naphthyl group and 2-naphthyl group, pyridine, imidazole, triazole, tetrazole and the like. And functional groups derived from nitrogen heterocyclic compounds. These compounds may be used alone or in combination of two or more as required. Among these, a compound having a phenyl group, a 3-methylphenyl group, a 4-hydroxyphenyl group, and a 4-cyanophenyl group is preferable because of availability.

  V in the phosphazene compound represented by the general formula (4) is not limited as long as it is 3 or more and 25 or less. When v is 3 or more, flame retardancy is exhibited, and when it is 25 or less, solubility in an organic solvent is high, which is preferable. Among these, it is more preferable that v is 3 or more and 10 or less because of availability.

  The w in the phosphazene compound represented by the general formula (5) is not limited as long as it is 3 or more and 10,000 or less. When w is 3 or more, flame retardancy is exhibited, and when it is 10,000 or less, solubility in an organic solvent is high, which is preferable. Among these, w is preferably 3 or more and 100 or less because of availability.

D and E in the phosphazene compound represented by the general formula (5) are not limited as long as they are organic groups having 3 to 30 carbon atoms. In this, D is _{-N = P (OC 6 H 5} ) 3, -N = P (OC 6 H 5) 2, -N = P (OC 6 H 5) (OC 6 H 4 OH) 2, - _{N = P (OC 6 H 4} OH) 3, -N = P (O) (OC 6 H 5), - N = P (O) (OC 6 H 4 OH) are preferred.

E is _{-P (OC 6 H 5) 4} , -P (OC 6 H 5) 3 (OC 6 H 4 OH), - P (OC 6 H 5) 2 (OC 6 H 4 OH) 2, -P ( _{OC 6 H 5) (OC 6} H 4 OH) 3, -P (OC 6 H 4 OH) 4, -P (O) (OC 6 H 5) 2, -P (O) (OC 6 H 4 OH) _2, such as _{-P (O) (OC 6 H} 5) (OC 6 H 4 OH) are preferred. A phosphorus compound may be used alone or in combination of two or more.

  The addition amount of the phosphorus compound is preferably 50 parts by mass or less from the viewpoint of developability and the like when the polyimide precursor is 100 parts by mass. 45 mass parts or less are preferable from a flame-retardant viewpoint of a hardening body, and 40 mass parts or less are more preferable. Moreover, if it is 5 mass parts or more, an effect is exhibited.

(F) Thermally reactive compound The photosensitive resin composition may contain a thermally reactive compound in order to improve the toughness, solvent resistance, heat resistance (thermal stability), and electrical insulation reliability of the film after firing. preferable. Examples of such a thermoreactive compound include a thermosetting resin and a reactive compound with a polyimide precursor.

  Examples of the thermosetting resin include an epoxy resin, a cyanate ester resin, an unsaturated polyester resin, a benzoxazine resin, a benzoxazoline, a phenol resin, a melamine resin, and a maleimide compound.

  Examples of the reactive compound with the polyimide precursor include a compound that reacts with a carboxyl group, an amino group, or a terminal acid anhydride in a polymer to form a three-dimensional crosslinked structure. Among them, a so-called thermal base generator that generates an amino group as a base by heating is preferable. Examples of thermal base generators include compounds in which the amino group of a base compound such as an amine is protected as a salt structure with an acid such as sulfonic acid, a compound protected with a dicarbonate compound, or a blocked isocyanate protected with an acid chloride compound (trademark) Name: TPA-B80E, manufactured by Asahi Kasei Chemicals Corporation) is preferably used. Such a base generator does not exhibit basicity at room temperature and is stable, and can be deprotected by heating to generate a base.

  When the amount of the polyimide precursor is 100 parts by mass, the amount of the thermally reactive compound added is preferably 50 parts by mass or less, more preferably 40 parts by mass or less from the viewpoint of developability. Moreover, if it is 2 mass parts or more, solvent resistance, heat resistance (thermal stability), and electrical insulation reliability will improve.

  The photosensitive resin composition can contain other compounds as long as the performance is not adversely affected. Specific examples thereof include heterocyclic compounds for improving adhesion and pigments and dyes for coloring the film.

  The heterocyclic compound is not limited as long as it is a cyclic compound containing a hetero atom. Here, examples of the hetero atom include oxygen, sulfur, nitrogen, and phosphorus. Specific examples of the cyclic compound containing a hetero atom include 2-methylimidazole, 2-undecylimidazole, 2-ethyl-4-methylimidazole, imidazole such as 2-phenylimidazole, and 1,2-dimethylimidazole. N-alkyl group-substituted imidazole, aromatic group-containing imidazole such as 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl- Imidazole compounds such as 4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, cyano group-containing imidazole such as 1-cyanoethyl-2-phenylimidazole, silicon-containing imidazole such as imidazolesilane, 5-methylbenzotriazo And triazole compounds such as 1- (1 ′, 2′-dicarboxyethylbenzotriazole) and 1- (2-ethylhexylaminomethylbenzotriazole), and oxazole compounds such as 2-methyl-5-phenylbenzoxazole. Can be mentioned. Examples of pigments and dyes include phthalocyanine compounds.

  The addition amount of other compounds is not limited as long as it is 0.01 part by mass or more and 30 parts by mass or less. If it is 0.01 mass part or more, there exists a tendency for adhesiveness and the coloring property to a film to fully improve, and if it is 30 mass parts or less, there will be no bad influence on photosensitivity.

  The photosensitive resin composition may optionally contain an organic solvent. The organic solvent is not limited as long as it can uniformly dissolve and / or disperse the polyimide precursor. Examples of such organic solvents include dimethyl ether, diethyl ether, methyl ethyl ether, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, and other ether compounds having 2 to 9 carbon atoms; acetone, methyl ethyl ketone A ketone compound having 2 to 6 carbon atoms; a saturated hydrocarbon compound having 5 to 10 carbon atoms such as normal pentane, cyclopentane, normal hexane, cyclohexane, methylcyclohexane, and decalin; benzene, toluene, Aromatic hydrocarbon compounds having 6 to 10 carbon atoms such as xylene, mesitylene and tetralin; methyl acetate, ethyl acetate, γ-butyrolactone, benzo Ester compounds having 3 to 9 carbon atoms such as methyl acid; halogen-containing compounds having 1 to 10 carbon atoms such as chloroform, methylene chloride and 1,2-dichloroethane; acetonitrile, N, N-dimethyl Examples thereof include nitrogen-containing compounds having 2 to 10 carbon atoms such as formamide, N, N-dimethylacetamide and N-methyl-2-pyrrolidone; and sulfur-containing compounds such as dimethyl sulfoxide.

  These organic solvents may be one kind or a mixture of two or more kinds as necessary. Particularly preferable organic solvents include ether compounds having 2 to 9 carbon atoms, ester compounds having 3 to 9 carbon atoms, aromatic hydrocarbon compounds having 6 to 10 carbon atoms, and 2 or more carbon atoms. Examples thereof include nitrogen-containing compounds having 10 or less carbon atoms.

  From the viewpoint of solubility of the polyimide precursor, triethylene glycol dimethyl ether, N-methyl-2-pyrrolidone, γ-butyrolactone, N, N-dimethylformamide, and N, N-dimethylacetamide are preferable.

<Photosensitive film>
The photosensitive resin composition can be suitably used for a photosensitive film. From the viewpoint of producing a photosensitive film, the concentration of the polyimide precursor in the photosensitive resin composition is preferably 1% by mass or more and 90% by mass or less. Further, the concentration of the polyimide precursor is preferably 1% by mass or more from the viewpoint of the film thickness of the photosensitive film, and preferably 90% by mass or less from the viewpoint of the viscosity of the photosensitive resin composition and the uniformity of the film thickness. Furthermore, the concentration of the polyimide precursor is more preferably 2% by mass or more and 80% by mass or less from the viewpoint of the film thickness of the resulting photosensitive film.

  Next, the manufacturing method of a photosensitive film is demonstrated. First, the photosensitive resin composition is applied (coated) to a substrate. Next, a photosensitive film is produced by heating the substrate coated with the photosensitive resin composition with a dryer at 95 ° C. for 30 minutes.

  As a base material, if it is a base material which is not damaged in the case of photosensitive dry film formation, it will not be limited. Examples of such a substrate include a silicon wafer, glass, ceramic, heat resistant resin, and carrier film. Examples of the carrier film include a polyethylene terephthalate film and a metal film. A heat-resistant resin and a carrier film are preferable from the viewpoint of easy handling, and a polyethylene terephthalate film is particularly preferable from the viewpoint of peelability after pressure bonding to the substrate.

  Examples of the coating method include bar coating, roller coating, die coating, blade coating, dip coating, doctor knife, spray coating, flow coating, spin coating, slit coating, and brush coating. After the coating, if necessary, a heat treatment called pre-baking may be performed with a hot plate or the like.

  It is good also as a laminated | multilayer film which provides the photosensitive film comprised with the photosensitive resin composition on a carrier film, and has a carrier film and a photosensitive film. In this case, the solution of the photosensitive resin composition is applied on an arbitrary carrier film by an arbitrary method and then dried to form a dry film.

  Moreover, it is good also as a laminated | multilayer film by providing at least one layer of arbitrary antifouling and protective cover films on a photosensitive film. As a cover film, if it is a film which protects photosensitive films, such as low density polyethylene, it will not be limited.

  Moreover, a flexible printed wiring board can be obtained by crimping | bonding the photosensitive film produced with the said manufacturing method so that the wiring of the base material which has wiring may be covered, performing alkali image development, and baking.

  Examples of the substrate having wiring in the flexible printed wiring board include a hard substrate such as a glass epoxy substrate and a glass maleimide substrate, or a flexible substrate such as a copper clad laminate. Among these, a flexible substrate is preferable from the viewpoint of bendability.

  In the formation method of a flexible printed wiring board, if a photosensitive film is formed in a base material so that wiring may be covered, it will not be limited. Examples of such a forming method include a method of performing a heat press, a heat laminate, a heat vacuum press, a heat vacuum laminate and the like in a state where the wiring side of a substrate having wiring and the photosensitive film are in contact with each other. Among these, from the viewpoint of embedding the photosensitive film between the wirings, a heat vacuum press or a heat vacuum laminate is preferable.

  The heating temperature at the time of laminating the photosensitive film on the substrate having wiring is not limited as long as the photosensitive film can adhere to the substrate. The heating temperature is preferably 30 ° C. or more and 400 ° C. or less from the viewpoint of adhesion to the substrate, decomposition of the photosensitive film, and side reaction. More preferably, it is 50 degreeC or more and 150 degrees C or less. The surface treatment of the substrate having wiring is not particularly limited, and examples thereof include hydrochloric acid treatment, sulfuric acid treatment, and sodium persulfate aqueous solution treatment.

  The photosensitive film can be subjected to negative photolithography by dissolving the portion other than the light irradiated portion by alkali development after the light irradiation. In this case, examples of the light source used for light irradiation include a high pressure mercury lamp, an ultrahigh pressure mercury lamp, a low pressure mercury lamp, a metal halide lamp, a xenon lamp, a fluorescent lamp, a tungsten lamp, an argon laser, and a helium cadmium laser. Among these, a high pressure mercury lamp and an ultrahigh pressure mercury lamp are preferable.

  The aqueous alkali solution used for development is not limited as long as it is a solution that can dissolve other than the light irradiation site. Examples of such a solution include a sodium carbonate aqueous solution, a potassium carbonate aqueous solution, a sodium hydroxide aqueous solution, a potassium hydroxide aqueous solution, and a tetramethylammonium hydroxide aqueous solution. From the viewpoint of developability, an aqueous sodium carbonate solution and an aqueous sodium hydroxide solution are preferred. Examples of the development method include spray development, immersion development, and paddle development.

  Next, the printed wiring board is formed by firing the printed wiring board to which the photosensitive film is pressure-bonded. Firing is preferably carried out at a temperature of 30 ° C. or higher and 400 ° C. or lower from the viewpoints of solvent removal, side reactions and decomposition. More preferably, it is 100 degreeC or more and 300 degrees C or less.

  The reaction atmosphere in the firing can be performed in an air atmosphere or an inert gas atmosphere. In the production of a printed wiring board, the time required for firing varies depending on the reaction conditions, but is usually within 24 hours, and particularly preferably in the range of 1 to 8 hours.

  The polyimide precursor and the photosensitive resin composition have excellent electrical insulation reliability, good warpage after curing, good developability, and chemical resistance when cured. Protective layer formation for printed wiring boards and circuit boards used for operation panels of various electronic devices in the field, insulating layer formation for laminated substrates, silicon wafers used for semiconductor devices, semiconductor chips, members around semiconductor devices, semiconductors It is used for film formation on electronic components for use in protection, insulation and adhesion of mounting substrates, heat sinks, lead pins, semiconductors, etc. A protective film that protects wiring formed on a silicon wafer, a copper clad laminate, a printed wiring board, or the like is called a coverlay.

  In addition, polyimide precursors and photosensitive resin compositions are used for flexible printed circuit (FPC) substrates, tape automation bonding (TAB) substrates, electrical insulating films and liquid crystal display substrates in various electronic devices, organic electroluminescence ( EL) It can be suitably used for a substrate for display, a substrate for electronic paper, a substrate for solar cell, particularly a coverlay for a flexible printed circuit.

(Example)
Next, examples performed for clarifying the effects of the present invention will be described.
In the following Examples and Comparative Examples, silicone diamine (KF-8010; manufactured by Shin-Etsu Chemical Co., Ltd.), TMEG (trade name: TMEG-100 (manufactured by Shin Nippon Chemical Co., Ltd.)), BPDA (manufactured by Mitsui Chemicals), APB (trade name: APB-N (manufactured by Mitsui Chemicals)), Jeffamine (trade name: Jeffamine XTJ-542 (manufactured by Huntsman)), phosphazene compound (trade name: FP-300, manufactured by Fushimi Pharmaceutical Co., Ltd.), Tris (butoxyethyl) phosphate (manufactured by Wako Pure Chemical Industries, Ltd.), blocked isocyanate (trade name: TPA-B80E, manufactured by Asahi Kasei Chemicals), EO-modified bisphenol A dimethacrylate (trade name: BPE-500 (Shin Nakamura Chemical Co., Ltd.) ), Pentaerythritol tri / tetra (meth) acrylate (trade name: Aronix M-306 (Toago) Manufactured by Seishin), ethanone 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] -1- (O-acetyloxime) (trade name: IRGACURE OXE 02 (Ciba Japan) ), Toluene (Wako Pure Chemical Industries, for organic synthesis), γ-butyrolactone (Wako Pure Chemical Industries), triethylene glycol dimethyl ether (Wako Pure Chemical Industries), sodium carbonate (Wako Pure Chemical Industries) Co., Ltd.), Kirest MZ-4A (manufactured by Kirest Co., Ltd.), TPEN (manufactured by Dojindo Laboratories Co., Ltd.), and nursem aluminum (manufactured by Nippon Kagaku Sangyo Co., Ltd.) were used for the reaction without any special purification.

<Weight average molecular weight measurement>
Gel permeation chromatography (GPC), which is a method for measuring the weight average molecular weight, was measured under the following conditions. N, N-dimethylformamide (manufactured by Wako Pure Chemical Industries, Ltd., for high performance liquid chromatograph) was used as a solvent, and 24.8 mmol / L lithium bromide monohydrate (manufactured by Wako Pure Chemical Industries, Ltd., purity before measurement). 99.5%) and 63.2 mmol / L phosphoric acid (manufactured by Wako Pure Chemical Industries, Ltd., for high performance liquid chromatograph) were used.
Column: Shodex KD-806M (manufactured by Showa Denko KK)
Flow rate: 1.0 mL / min Column temperature: 40 ° C
Pump: PU-2080 Plus (manufactured by JASCO)
Detector: RI-2031Plus (RI: differential refractometer, manufactured by JASCO)
UV-2075 Plus (UV-VIS: UV-Visible Absorber, manufactured by JASCO)
A calibration curve for calculating the weight average molecular weight was prepared using standard polystyrene (manufactured by Tosoh Corporation).

<Production of photosensitive dry film>
The photosensitive dry film was manufactured from the photosensitive resin composition as follows. The coating of the photosensitive resin composition was performed by a doctor blade method using FILMCATOR (manufactured by TESTER SANGYO, PI1210). First, the photosensitive resin composition was dropped onto a PET film (N152Q, manufactured by Teijin Deyupon Film Co., Ltd.), and coating was performed with a clearance of 150 μm. Next, the coated film was dried at 95 ° C. for 30 minutes using a drier (manufactured by ESPEC, SPHH-10 l) to obtain a photosensitive dry film.

<Lamination conditions>
Lamination was performed using a vacuum press (made by Meiki Seisakusho). Lamination was performed under the conditions of a pressing temperature of 80 ° C., a pressing pressure of 0.5 MPa, and a pressing time of 30 seconds.

<Developability evaluation>
The developability evaluation was performed as follows. After laminating a photosensitive dry film on the copper clad laminate under the above laminating conditions, it was exposed at 30-270 mJ / cm ² . Subsequently, alkali development with a 1% by mass aqueous sodium carbonate solution and rinsing with water were performed, and the pattern was evaluated with an optical microscope after drying. A circular pattern having a 100 μm diameter (interval of 100 μm pitch) was used as the mask. The case where the copper surface appeared in the unexposed part by development and the residual film ratio was 75% or more was marked with “◯”, and the case where the other resolution was inferior or the residual film thickness was less than 75% was marked with “X”.

<Insulation reliability evaluation>
The insulation reliability evaluation was performed as follows. After laminating a photosensitive dry film on a comb-type substrate with a line and space of 20 μm / 20 μm under the above laminating conditions, exposure and development are performed under the above conditions, followed by 120 ° C. for 1 hour, followed by 180 ° C. for 1 hour. Firing was performed. A migration tester cable was soldered to the film, and an insulation reliability test was conducted under the following conditions.
Insulation degradation evaluation system: SIR-12 (Enomoto Kasei Co., Ltd.)
HAST chamber: EHS-211M (Espec Corp.)
Temperature: 110 ° C
Humidity: 85%
Applied voltage: 2V
Insulation resistance: Insulation resistance value after the test after 15 hours and × less than 1.0 × 10 ⁶ Ω, and less than ^{1.0 × 10 6 Ω~1.0 × 10 8} Ω △ and, 1.0 × A value of 10 ⁸ Ω or more was rated as ◯.
Insulation durability: The case where the insulation resistance value is less than 1.0 × 10 ⁴ Ω for less than 150 hours is indicated as “X”, the case where the insulation resistance value is maintained at 1.0 × 10 ⁴ Ω or more for 150 hours or more is ○, and 300 hours or more is 1 The case where 0.0 × 10 ⁴ Ω or more was maintained was rated as “◎”.

<Measurement of warpage after firing>
The obtained photosensitive dry film was laminated on Kapton (registered trademark) under the above-mentioned lamination conditions, and then baked at 120 ° C. for 1 hour and subsequently at 180 ° C. for 1 hour. The film was cut into 5 cm squares, and those with a floating height of 10 mm or less were marked with ◯, and those with a floating height higher than that were marked with x.

<Bending test after firing>
The film obtained after curing was bent at 180 degrees (goose folding), and the cover film was visually observed for cracking and peeling. When there was no crack or peeling, it was rated as “good”, and when there was a crack or peeling, it was marked as “poor”.

<Flame retardance test>
The flame retardancy test was performed by laminating the polyimide film (Kapton EN-100 trade name, manufactured by Toray DuPont) on both sides using the photosensitive dry film under the above laminating conditions, followed by 1 hour at 120 ° C., followed by 180 Firing was carried out at a temperature of 1 hour.

  The obtained film was cut to a width of 1 cm and a length of 4 cm. Next, the process of igniting one end of the test piece and spreading it was visually observed. A sample that was extinguished during the course was marked with ◯, and a sample that had all burned was marked with ×.

<Polyimide precursor (1)>
Under a nitrogen atmosphere, a separable flask was charged with triethylene glycol dimethyl ether (12 g), γ-butyrolactone (28 g), toluene (20.0 g), silicone diamine (KF-8010, 23.1 mmol), TMEG (39.00 mmol). The mixture was stirred at 120 ° C. for 1 hour. Subsequently, a Dean Stark apparatus and a reflux were attached, and the mixture was heated and stirred at 180 ° C. for 1 hour. After removing toluene as an azeotropic solvent, the mixture was cooled to 25 ° C., APB-N (13.68 mmol) was added, and the mixture was stirred at 25 ° C. for 8 hours. After stirring, a mixed solvent of triethylene glycol dimethyl ether / γ-butyrolactone was added so that the polymer solid concentration would be 25% by mass to obtain a solution of the polyimide precursor (1). The weight average molecular weight was 30000, and the silicon structure was 49% by mass.

<Polyimide precursor (2)>
Under a nitrogen atmosphere, a separable flask was charged with triethylene glycol dimethyl ether (12 g), γ-butyrolactone (28 g), toluene (20.0 g), silicone diamine (KF-8010, 5.9 mmol), TMEG (39.00 mmol). The mixture was stirred at 120 ° C. for 1 hour. Subsequently, a Dean Stark apparatus and a reflux were attached, and the mixture was heated and stirred at 180 ° C. for 1 hour. After removing toluene as an azeotropic solvent, the mixture was cooled to 25 ° C., APB-N (30.8 mmol) was added, and the mixture was stirred at 25 ° C. for 8 hours. After stirring, a mixed solvent of triethylene glycol dimethyl ether / γ-butyrolactone was added so that the polymer solid content concentration was 25% by mass to obtain a solution of the polyimide precursor (2). The weight average molecular weight was 30000, and the silicon structure was 16% by mass.

<Polyimide precursor (3)>
Under a nitrogen atmosphere, a separable flask was charged with triethylene glycol dimethyl ether (12 g), γ-butyrolactone (28 g), toluene (20.0 g), silicone diamine (KF-8010, 23.1 mmol), BPDA (39.00 mmol). The mixture was stirred at 120 ° C. for 1 hour. Subsequently, a Dean Stark apparatus and a reflux were attached, and the mixture was heated and stirred at 180 ° C. for 1 hour. After removing toluene as an azeotropic solvent, the mixture was cooled to 25 ° C., and subsequently maleic anhydride (0.53 mmol) and APB-N (13.68 mmol) were added, followed by stirring at 25 ° C. for 8 hours. After stirring, a mixed solvent of triethylene glycol dimethyl ether / γ-butyrolactone was added so that the polymer solid content concentration was 25% by mass to obtain a solution of the polyimide precursor (3). The weight average molecular weight was 33200. The silicon structure was 55% by mass.

<Polyimide precursor (4)>
Under a nitrogen atmosphere, put Jeffamine XJT-542 (4.45 mmol), γ-butyrolactone (32.5 g), APB-N (9.05 mmol), and 5BTA (15 mmol) in a separable flask, and set the temperature of the oil bath. The mixture was gradually raised and heated and stirred at 60 ° C. for 3 hours. Furthermore, it heat-stirred at 70 degreeC for 1 hour, and obtained the gamma-butyrolactone solution (polyimide precursor (4)) of the polyimide precursor. The weight average molecular weight was 28000.

[Examples 1 to 7]
A solution of a polyimide precursor (1), a polyimide precursor (2), and a polyimide precursor (3) was mixed in the composition shown in Table 1 below to prepare a photosensitive resin composition. The obtained photosensitive resin composition was formed into a dry film by the above-described method to obtain a photosensitive film. This photosensitive film was laminated on a flexible copper clad laminate by the method described above. The obtained laminated film was evaluated for insulation reliability, developability, bendability, warpage, and flame retardancy. The results are shown in Table 2 below.

[Comparative Examples 1 to 4]

  A solution of the polyimide precursor (1) and the polyimide precursor (4) was mixed with the composition shown in Table 1 below to prepare a photosensitive resin composition. The obtained photosensitive resin composition was formed into a dry film by the above-described method to obtain a photosensitive film. This photosensitive film was laminated on a flexible copper clad laminate by the method described above. The obtained laminated film was evaluated for insulation reliability, developability, bendability, warpage, and flame retardancy. The results are shown in Table 2 below.

表１及び表２の結果から、実施例１〜実施例７は比較例１〜比較例４と比較して、絶縁信頼性、現像性、折り曲げ性、そりに優れていることが分かる。

From the results of Tables 1 and 2, it can be seen that Examples 1 to 7 are superior in insulation reliability, developability, bendability, and warpage as compared with Comparative Examples 1 to 4.

  Since the photosensitive resin composition of the present invention is excellent in electrical insulation reliability, developability, bendability, warpage, and flame retardancy, the surface protective film of the semiconductor device, the interlayer insulating film, and the insulating film for rewiring, It can be suitably used as a protective film of a device having a bump structure, an interlayer insulating film of a multilayer circuit, a cover coat of a flexible copper-clad plate, a liquid crystal alignment film and the like.

Claims (12)

A polyimide precursor having a polyimide structure represented by the following general formula (1) and a polyamic acid structure represented by the following general formula (2) as repeating structural units, respectively, and a chelating agent, the polyimide precursor A photosensitive resin composition comprising 0.1 to 25 parts by mass of the chelating agent with respect to 100 parts by mass of the body.

(In Formula (1), R ₁ is a tetravalent organic group having 1 to 30 carbon atoms, and may be the same or different. R ₂ is a divalent organic group having 1 to 30 carbon atoms. And R ₃ is a monovalent organic group having 1 to 30 carbon atoms, which may be the same or different, and n represents an integer of 1 to 30.)

(In Formula (2), R ₄ is a divalent organic group having 1 to 80 carbon atoms. R ₅ is a tetravalent organic group having 1 to 30 carbon atoms, and each is the same or different. May be.)   2. The photosensitive resin composition according to claim 1, wherein the chelating agent is dissolved in an amount of 0.1% by weight or more in any one of gamma butyrolactone, methyl ethyl ketone, and N-methyl-2-pyrrolidone.   The photosensitive resin composition according to claim 1, comprising a (meth) acrylate compound having at least two photopolymerizable unsaturated double bonds and a photopolymerization initiator. . The (meth) acrylate compound having at least two or more photopolymerizable unsaturated double bonds includes both a compound having two double bonds and a compound having three or more double bonds. The photosensitive resin composition according to any one of claims 1 to 3 , wherein Photosensitive resin composition according to any one of claims 1 to 4, characterized in that it comprises a phosphorus compound.   6. The photosensitive resin composition according to claim 5, wherein the phosphorus compound has at least one structure selected from the group consisting of a phosphate ester structure and a phosphazene structure.   The photosensitive resin composition according to claim 1, comprising a thermoreactive compound.   A photosensitive film obtained by applying the photosensitive resin composition according to claim 1 to a substrate. Laminate film characterized by comprising a carrier film, and a photosensitive film of claim 8 Symbol mounting provided on the carrier film. The laminated film of claim 9 Symbol mounting characterized by comprising a cover film formed on the photosensitive film. Printed circuit board, wherein a substrate having a wiring that comprises a cover lay that is made up of a multilayer film of the substrate so as to cover provided claims 9 Symbol mounting. Printed circuit board, wherein a substrate having a wiring that comprises a cover lay that is made up of a multilayer film of the substrate so as to cover provided claims 9 or claim 1 0 Symbol placement.