JP2008070477A - Photosensitive resin film and method of manufacturing circuit board panel using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive resin film having an insulated pellicle which needs no high temperature treatment during curing or processing, has flexibility superior in folding durability or bending, also has excellent preservation stability at a room temperature, anti-chemical and electric characteristics, and is hardly scratched. <P>SOLUTION: The photosensitive resin film is obtained by applying a photosensitive resin composition blending 1-20 pts.wt of a photo-initiator and 30-60 pts.wt of mono-functional or poly-functional acrylate to 100 pts.wt of siloxane-contained polyamic acid resin as an indispensable component, on a base material film and by drying it. Polyamic acid contains an unsaturated group denoted by CH<SB>2</SB>=CH-R-. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a photosensitive resin film produced from a photosensitive resin composition containing a novel siloxane-containing polyamic acid resin, and an insulating film-formed substrate using the same. Specifically, the present invention relates to a printed wiring board resist composition, a photosensitive resin film suitable for forming a cured film thereof, and a method for producing an insulating film-formed circuit board using the same.

  In recent years, ultraviolet curable photosensitive resin compositions have been widely used in a wide range of fields such as paints, adhesives and resists for various reasons such as high productivity, low pollution and energy saving. Also in the field of printed wiring board processing, ink-type and film-type cover materials such as solder resist ink and coverlay film are being replaced from conventional thermosetting compositions to ultraviolet curable compositions.

  In addition, as the density and weight are reduced due to significant advances in electronic technology, replacement of a conventional rigid (hard) substrate to a flexible substrate is progressing.

  Usually, as the characteristics of the cover material after curing, the cover material used for the rigid substrate was not so flexible, but when using the cover material for the flexible substrate, in order to take advantage of the characteristics of the flexible substrate, The cover material is also required to be more flexible.

  Therefore, JP-A-7-207211 contains an unsaturated group-containing polycarboxylic acid resin that is a reaction product of an epoxy resin, an unsaturated group-containing monocarboxylic acid, and a carboxylic anhydride, a photopolymerization initiator, and the like. A curable photosensitive material is described. However, with such materials, sufficient flexibility and flexibility are not ensured, resulting in poor folding resistance, and there is a problem that the substrate warps after processing. This improvement has been widely demanded. It was done. For this reason, the composition which has siloxane polyimide as a main component was proposed as a component which expresses low elasticity like Unexamined-Japanese-Patent No. 2004-294882. Although such a composition reduces the warpage of the substrate after processing, there are problems such as high cost and poor room temperature storage stability of the composition.

  Further, as a cover material, a film-type cover material that is superior in workability and smoothness as compared with an ink format has been required.

JP-A-7-207211 JP 2004-294882 A

  The present invention has flexibility with excellent folding resistance and flexibility, excellent storage stability at room temperature, chemical resistance, electrical properties, hardly scratched, and high temperature during curing or processing. An object of the present invention is to provide a photosensitive resin film capable of forming an insulating film that does not require treatment.

  As a result of intensive studies to solve the above problems, the present inventors have obtained a polyamic acid resin containing a specific siloxane moiety and an aromatic moiety having an unsaturated group, and photosensitivity comprising the same. It discovered that the photosensitive resin film produced from a resin composition could solve the said subject, and completed this invention.

（式中、Arは芳香族テトラカルボン酸からカルボキシル基を除いた４価のテトラカルボン酸残基を示し、R₁は炭素数１〜６のアルキル基又はフェニル基、Ｒ₂は炭素数２〜６のアルキレン基又はフェニレン基、lは０〜１０の数を示し、Ｒ₃は２価の基又は直結合を示し、Ｒ₄はＣＨ₂＝ＣＨ−Ｒ₆−で表される基を示し、Ｒ₆は直結合、炭素数１〜６のアルキレン基又はフェニレン基を示し、Ｒ₅はジアミン化合物からアミノ基を除いた２価ジアミン残基を示すが、一般式（１）及び（２）に含まれるジアミン残基である場合を除く。また、m、n及びoは各構成単位の存在モル比を表し、ｍは０．３〜０．９５、nは０．０５〜０．７及びoは０〜０．５の範囲である。） That is, the present invention relates to a photosensitive resin film obtained by applying and drying a photosensitive resin composition on a base film, and the photosensitive resin composition contains 30 moles of a structural unit represented by the following formula (1). % To 95 mol%, 100 parts by weight of the siloxane-containing polyamic acid resin containing 5 mol% to 70 mol% of the structural unit represented by formula (2) and 0 to 50 mol% of the structural unit represented by formula (3) A photosensitive resin composition comprising 1 to 20 parts by weight of a photopolymerization initiator and 30 to 60 parts by weight of a monofunctional or polyfunctional acrylate as essential components. It is.

(In the formula, Ar represents a tetravalent tetracarboxylic acid residue obtained by removing a carboxyl group from an aromatic tetracarboxylic acid, R ₁ represents an alkyl group having 1 to 6 carbon atoms or a phenyl group, and R ₂ represents 2 to 2 carbon atoms. 6 represents an alkylene group or a phenylene group, l represents a number of 0 to 10, R ₃ represents a divalent group or a direct bond, R ₄ represents a group represented by CH ₂ ═CH—R ₆ —, R ₆ represents a direct bond, an alkylene group having 1 to 6 carbon atoms, or a phenylene group, and R ₅ represents a divalent diamine residue obtained by removing an amino group from a diamine compound. In general formulas (1) and (2), Except when it is a diamine residue, m, n and o represent the molar ratio of each constituent unit, m is 0.3 to 0.95, n is 0.05 to 0.7 and o. Is in the range of 0 to 0.5.)

Moreover, this invention is obtained from the photosensitive resin composition by which 0.1-10 weight part of triazine thiol compounds represented by following formula (4) are mix | blended with respect to 100 weight part of said siloxane containing polyamic acid resins. It is a photosensitive resin film.

  In addition, the present invention provides a negative type film by forming the above-mentioned photosensitive resin film on a circuit board on which a conductor circuit is formed so that a desired portion of the conductor circuit is coated, and then exposing, developing and curing. A circuit board manufacturing method is characterized in that an insulating film is formed.

Hereinafter, the present invention will be described in detail.
The siloxane-containing polyamic acid resin constituting the photosensitive resin film of the present invention has a structural unit represented by the above formulas (1) and (2), but preferably has a structural unit represented by the formula (3). . In the formulas (1), (2) and (3), Ar represents a tetravalent tetracarboxylic acid residue obtained by removing a carboxyl group from an aromatic tetracarboxylic acid. Or two or more types.

In Formula (1), R ₁ represents an alkyl group having 1 to 6 carbon atoms or a phenyl group, preferably an alkyl group having 1 to ₂ carbon atoms, and R ₂ represents an alkylene group or phenylene group having 2 to 6 carbon atoms. As shown, an alkyl group having about 2 to 4 carbon atoms is preferred, and l represents a number of 0 to 10, and the average value of l is preferably 7 to 10. The abundance of the structural unit represented by the formula (1) in the resin is 30 to 95 mol%, preferably 50 to 80 mol%.

In the formula (2), R ₃ represents a divalent group or a direct bond, and is preferably any one selected from a direct bond, CH ₂ , C (CH ₃ ) ₂ and SO ₂ . R ₄ is CH ₂ = CH-R ₆ - is a group represented by, R ₆ is a direct bond, although an alkylene group or a phenylene group having 1 to 6 carbon atoms, R ₄ is the reaction that a vinyl group From the viewpoint of sex. The amount of the structural unit represented by the formula (2) in the resin is 5 to 70 mol%, preferably 5 to 30 mol%.

In Formula (3), R ₅ represents a divalent diamine residue, but is not a diamine residue contained in Formula (1) and Formula (2). The abundance of the structural unit represented by the formula (3) in the resin is 0 to 50 mol%, preferably 5 to 30 mol%.

  The structural units represented by the above formulas (1) to (3) have an amic acid bond as obtained by a reaction between a diamine and an aromatic tetracarboxylic acid, but even if a part thereof is imidized. good. However, in order to ensure good alkali developability, the imidation ratio is desirably less than 30%.

  Ar in the formulas (1) to (3) represents a tetravalent residue obtained by removing tetracarboxylic acid from aromatic tetracarboxylic acid, and aromatic tetracarboxylic dianhydride should be used as the aromatic tetracarboxylic acid. Therefore, some examples of Ar will be explained by showing aromatic tetracarboxylic dianhydrides. Examples of the aromatic tetracarboxylic dianhydride include the following compounds. Pyromellitic dianhydride, 2,2 ', 3,3'-, 2,3,3', 4'- or 3,3 ', 4,4'-benzophenone tetracarboxylic dianhydride, 2,3 , 6,7-, 1,2,4,5-, 1,4,5,8-, 1,2,6,7- or 1,2,5,6-naphthalene-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2,5,6-tetracarboxylic dianhydride, 2,6- or 2,7-dichloronaphthalene-1 , 4,5,8-tetracarboxylic dianhydride, 2,3,6,7- (or 1,4,5,8-) tetrachloronaphthalene-1,4,5,8- (or 2,3 , 6,7-) tetracarboxylic dianhydride, 3,3 ", 4,4"-, 2,2 ', 3,3'- or 2,3,3', 4'-biphenyltetracar Acid dianhydride, 3,3 ", 4,4"-, 2,3,3 ", 4"-or 2,2 ", 3,3" -p-terphenyltetracarboxylic acid Anhydride, 2,2-bis (2,3- or 3,4-dicarboxyphenyl) -propane dianhydride, bis (2,3-dicarboxyphenyl) ether dianhydride, bis (2,3- or 3.4-dicarboxyphenyl) methane dianhydride, bis (2,3- or 3,4-dicarboxyphenyl) sulfone dianhydride, 1,1-bis (2,3- or 3,4-dicarboxy Phenyl) ethane dianhydride, 2,3,8,9-, 3,4,9,10-, 4,5,10,11- or 5,6,11,12-perylene-tetracarboxylic dianhydride 1,2,7,8-, 1,2,6,7- or 1,2,9,10-phenanthrene-tetracarboxylic dianhydride, cycl Lopentane-1,2,3,4-tetracarboxylic dianhydride, pyrazine-2,3,5,6-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride Thiophene-2,3,4,5-tetracarboxylic dianhydride, 4,4′-oxydiphthalic dianhydride. Moreover, these can be used 1 type or in mixture of 2 or more types. Preferred examples include pyromellitic anhydride, 4,4′-oxydiphthalic dianhydride, benzophenone tetracarboxylic dianhydride, biphenyl tetracarboxylic dianhydride, biphenyl ether tetracarboxylic dianhydride, and the like. Among these, benzophenone tetracarboxylic dianhydride and biphenyl tetracarboxylic dianhydride are preferable.

Equation (3) R ₅ is in the so equation (1) as and is a divalent residue except amino group from a diamine compound other than the diamine compound contained in (2), R ₅ a diamine compound The following compounds can be mentioned by explaining p-phenylenediamine, m-phenylenediamine, 4,4′-diaminodiphenylmethane, 4,4′-diaminophenylethane, 4,4′-diaminophenyl ether, 4,4′-didiaminophenyl sulfide, 4,4 ′ -Didiaminophenylsulfone, 1,5-diaminonaphthalene, 3,3-dimethyl-4,4'-diaminobiphenyl, 5-amino-1- (4'-aminophenyl) -1,3,3-trimethylindane, 4,4'-diaminobenzanilide, 3,5-diamino-4'-trifluoromethylbenzanilide, 3,4'-diaminodiphenyl ether, 2,7-diaminofluorene, 2,2-bis (4-aminophenyl) Hexafluoropropane, 4,4′-methylene-bis (2-chloroaniline), 2,2 ′, 5,5′-tetrachloro-4, 4'-diaminobiphenyl, 2,2'-dichloro-4,4'-diamino-dimethoxybiphenyl, 3,3'-dimethoxy-4,4'-diaminobiphenyl, 4,4'-diamino-2,2'- Bis (trifluoromethyl) biphenyl, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane, 1,4- Bis (4-aminophenoxy) benzene, 4,4′-bis (4-aminophenoxy) biphenyl, 1,3′-bis (4-aminophenoxy) benzene, 9,9-bis (4-aminophenyl) fluorene, 4,4 '-(p-phenyleneisopropylidene) bisaniline, 4,4'-(m-phenyleneisopropylidene) bisaniline, 2,2'-bis [4- (4-amino-2-to Trifluoromethyl) phenoxy] -octafluorobiphenyl, hydroxyaminobiphenyl and the like.

  An example of the method for producing a siloxane-containing polyamic acid resin used in the present invention will be described. First, an aromatic dianhydride is added to a solvent and dissolved. While stirring this, two or more diamines including siloxane diamine are gradually added under a nitrogen atmosphere and ice cooling. Then, a siloxane-containing polyamic acid resin is obtained by reacting with stirring for 2 to 8 hours. The siloxane-containing polyamic acid resin obtained by such a method is a mixture of resins having different degrees of polymerization. In addition, it is good also as random polymerization type or block polymerization type polyamic acid resin by changing the addition method of diamine.

  As a solvent for performing the above reaction, an organic solvent such as triethylene glycol dimethyl ether (triglyme), diethylene glycol dimethyl ether (diglyme), dimethylacetamide, N-methylpyrrolidone, or a mixed solvent thereof can be used.

  It is desirable that the acid dianhydride and the diamine are added in approximately equimolar amounts. The reaction can be carried out without proceeding imidization by carrying out the reaction at room temperature or lower, preferably around 0 ° C. The degree of polymerization can be changed by changing the use ratio of diamine and aromatic dianhydride.

  The siloxane-containing polyamic acid resin thus obtained is mixed with a photopolymerization initiator and acrylate to form a photosensitive resin composition. Since this siloxane-containing polyamic acid resin has flexibility even after being cured, it can be used for applications requiring flexibility and is suitable as a resin component used in a photosensitive resin composition. Moreover, since it has a carboxy group in the side chain, it is also suitable for development with an alkaline aqueous solution.

  The photosensitive resin composition constituting the photosensitive resin film of the present invention comprises a siloxane-containing polyamic acid resin, a photopolymerization initiator, and a monofunctional or polyfunctional acrylate (hereinafter also referred to as acrylate) as essential components. Resins, sensitizers, solvents and the like can be added as necessary. By setting it as such a composition, not only will it have the characteristic which was more excellent as a photosensitive resin composition, but the use will also be expanded. In addition, the photosensitive resin film of this invention is obtained by apply | coating and drying on a base film what added the solvent to the photosensitive resin composition and made it varnish-like. And in description about the compounding quantity or compounding ratio of each component (except a solvent), it is understood as description in the state which does not contain a solvent.

  Examples of the acrylate include 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl acryloyl phosphate, 2-methoxyethoxyethyl acrylate, 2-ethoxyethoxyethyl acrylate, and tetrahydrofurfryl acrylate. , Phenoxyethyl acrylate, isodecyl acrylate, stearyl acrylate, lauryl acrylate, glycidyl acrylate, allyl acrylate, ethoxy acrylate, methoxy acrylate, N, N′-dimethylaminoethyl acrylate, benzyl acrylate, 2-hydroxyethylacryloyl phosphate, dicyclopenta Dienyl acrylate, dicyclopentadiene ethoxya Monoacrylates such as relate, dicyclopentenyl acrylate, dicyclopentenyloxyethyl acrylate, 1,3-butanediol diacrylate, 1,4-butanediol diacrylate, 1,6-butanediol diacrylate, diethylene glycol diacrylate, Neopentyl glycol diacrylate, polyethylene glycol 200 diacrylate, polyethylene glycol 400 diacrylate, polyethylene glycol 600 diacrylate, diethylene glycol diacrylate, neopentyl glycol diacrylate, hydroxypivalate ester neopentyl glycol diacrylate, triethylene glycol diacrylate, Bis (acryloxyethoxy) bisphenol A, bis (acryloxy) Ethoxy) tetrabromobisphenol A, tripropylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, tris (2-hydroxyethyl) isocyanate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypenta It is possible to use polyfunctional acrylates such as acrylates. In the photosensitive resin composition constituting the photosensitive resin film of the present invention, the acrylate is 30 to 60 parts by weight, preferably 35 to 55 parts by weight, and more preferably 40 parts by weight with respect to 100 parts by weight of the siloxane-containing polyamic acid resin. It is good to add -50 weight part. By making the addition amount of acrylate within the above range, plating resistance and scratch resistance are improved. When the scratch resistance of the photosensitive film is evaluated in accordance with JIS K5400 as pencil hardness, the hardness range is preferably HB to 7H, more preferably F to 7H, and even more preferably H to H. A hardness range of 7H is good.

  Examples of the photopolymerization initiator include acetophenone, 2,2-dimethoxyacetophenone, p-dimethylaminoacetophenone, Michler's ketone, benzyl, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-propyl ether, benzoin isopropyl Ether, benzoin n-butyl ether, benzyldimethylketal, thioxazone, 2-chlorothioxazone, 2-methylthioxazone, 2-hydroxy-2-methyl-1-phenyl-1-one, 1- (4-isopropyl Various photopolymerization initiators such as phenyl) -2-hydroxy-2-methylpropan-1-one, methylbenzoyl formate, 1-hydroxycyclohexyl phenyl ketone and the like can be used. The preferable usage-amount of a photoinitiator is 1-20 weight part with respect to 100 weight part of siloxane containing polyamic acid resins, Preferably it is 1-10 weight part.

  The photosensitive resin composition contains a triazine thiol compound represented by the formula (4), that is, 6-amino-1,3,5-triazine-2,4-, based on 100 parts by weight of the siloxane-containing polyamic acid resin. It is preferable to blend 0.1 to 10 parts by weight of dithiol (hereinafter referred to as ATD). More preferably, it is 0.1 to 5 parts by weight, and still more preferably 0.3 to 3 parts by weight. By using such a composition, chemical resistance, particularly resistance to a plating solution such as tin and gold is improved. A part of the amino group of ATD may be a salt such as hydrochloride, but when the ratio of the salt terminal is increased, the plating resistance and the migration characteristics tend to be lowered.

  In addition to ATD, the photosensitive resin composition includes 1,3,5-triazine-2,4,6-trithiol, 6-dibutylamino-1,3,5-triazine for the purpose of improving plating resistance. Triazine derivatives such as -2,4-dithiol, tetrasol derivatives such as 5-aminotetrazole, and the like may be added as additives. When these are used in combination, the blending amount is preferably equal to or less than the blending amount of ATD, more preferably 0.1 to 5 parts by weight with respect to 100 parts by weight of the siloxane-containing polyamic acid resin. A range of 5 to 2 parts by weight is most preferred.

  It is also advantageous to add a sensitizer. In this case, various amines such as benzophenone can be used as the sensitizer. The sensitizer is added in an amount of 0.01 to 2 parts by weight, preferably 0.05 to 0.5 parts by weight, based on 100 parts by weight of the siloxane-containing polyamic acid resin.

  The viscosity of the photosensitive resin composition can be adjusted with various organic solvents. Preferred organic solvents for use include triethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dimethylacetamide, N-methylpyrrolidone, propylene glycol monomethyl ether acetate, ethyl lactate, or a mixed solvent thereof. The amount of the solvent used is preferably in the range of 10 to 200 parts by weight with respect to 100 parts by weight of the solid content of the photosensitive resin composition. In addition, the photosensitive resin composition which contains 10% by weight or more of the solvent and exhibits a liquid state at room temperature is a varnish-like photosensitive resin composition. Moreover, when the organic solvent used as a reaction solvent at the time of polyamic acid resin manufacture remains, it calculates as this solvent.

  Although the component which reacts with carboxy groups, such as an epoxy, can also be added to the photosensitive resin composition, the addition amount is 100 weight part of solid content of the photosensitive resin composition so that room temperature storage stability may not be impaired. On the other hand, it is preferable to add less than 10 parts by weight, preferably less than 5 parts by weight.

  Moreover, well-known pigments, such as a phthalocyanine green and a phthalocyanine blue, can be added to the photosensitive resin composition in the range which does not impair the various characteristics as a photosensitive resin film, for example, a solder resist. The preferable addition amount of the pigment in that case is 1 to 20 weight% with respect to the photosensitive resin composition (solid content). Furthermore, it is possible to add a well-known filler to the photosensitive resin composition as needed.

The preferable composition of the solid content (including the monomer and excluding the solvent) of the photosensitive resin composition constituting the photosensitive resin film of the present invention is as follows.
Siloxane-containing polyamic acid resin: 52-76 wt%, preferably 60-71 wt%, photopolymerization initiator: 0.6-13 wt%, preferably 0.6-7 wt%, acrylate: 18-37 wt%, preferably 26- 33 wt%, ATD: 0.05-7 wt%, preferably 0.05-3.4 wt%, sensitizer: 0-1.5 wt%, preferably 0.03-0.35 wt%, from other monomers Resin component: 0 to 8 wt%, preferably 0 to 4 wt%.

  The photosensitive resin film of this invention can express a softness | flexibility and various characteristics by mix | blending the said various additives and solvent with the said ratio with the said resin component preferably in the said ratio, and mixing uniformly. And it can be in the form of a film or the like obtained by applying and drying a varnish-like, viscous liquid or ink-like photosensitive resin composition on a substrate film. The organic solvent solution of the siloxane-containing polyamic acid resin is conveniently an organic solvent solution used for the synthesis reaction of the polyamic acid resin, but if necessary, it can be concentrated, diluted or mixed or replaced with another organic solvent. May be.

  The photosensitive resin film of the present invention is coated with a solution of the photosensitive resin composition on a base material such as a PET film that has been subjected to a mold release treatment in a thickness of 5 to 100 μm, preferably 10 to 50 μm, By carrying out temporary drying at 50 to 140 ° C., preferably 80 to 140 ° C., more preferably 100 to 140 ° C., a photosensitive resin film can be obtained. When the temperature exceeds 140 ° C., imidization of the photosensitive resin composition proceeds and development becomes difficult. Therefore, drying within the above range is preferable.

  The photosensitive resin film of the present invention can be used in accordance with a generally known method of use, but when applied to a wiring board, a method of thermocompression bonding to the wiring board using a laminator is generally used. In this case, the lamination temperature is preferably 35 to 120 ° C, more preferably 40 to 110 ° C. The circuit board obtained by laminating is selectively exposed using a photomask having a predetermined mask pattern, the unexposed portion is developed with an alkaline aqueous solution, and the temperature is 120 to 200 ° C. for 20 to 120 minutes. It can be cured by heat treatment.

  Thus, the laminate comprising the wiring board / photosensitive resin film layer obtained by laminating is preferably used particularly for processing of a flexible wiring board because the photosensitive resin film of the present invention is excellent in flexibility. it can. In addition, the wiring board using the photosensitive resin film of the present invention has a good balance of the cured product characteristics of the photosensitive resin film, such as heat resistance, plating resistance, moisture resistance, electrical characteristics, and scratch resistance. Suitable for applications that require characteristics. These characteristics are derived from the characteristics of the siloxane-modified polyamic acid resin, and have double bonds and carboxylic acid groups. Therefore, they can be polymerized by light or heat to form a cured product having a three-dimensional structure. As a result, flexibility is maintained. For these reasons, superior heat resistance, plating resistance, moisture resistance, and flexibility are imparted as compared with ordinary photosensitive resins alone or mixtures thereof.

  The photosensitive resin film of the present invention has high storage stability, can be developed with a dilute alkaline aqueous solution after circuit processing using ultraviolet rays, and can be cured at a low temperature range of 200 ° C. or less. It is suitable for solder resist, plating resist, etc. at the time of printed wiring board manufacture. Furthermore, since the cured product has high flexibility and is excellent in bending resistance, flexibility, and electrical characteristics, it can be preferably used as a resist for flexible printed wiring boards that require these flexible characteristics. .

  Unless otherwise specified in the examples of the present invention, various measurements and evaluations are as follows.

[Evaluation of photolithography performance]
The photolithographic performance was evaluated as to whether or not Via having a diameter of 500 μm could be resolved with a 1% sodium carbonate aqueous solution. Specifically, a film-shaped photosensitive resin composition with a film thickness of 25 μm is thermocompression bonded under the conditions of pressure 1 MPa and 80 ° C. on the copper foil surface side of a flexible substrate (Espanex: MC12-20-00CEM manufactured by Nippon Steel Chemical). Lamination was performed using a roll laminator. An exposure mask (high-tech mercury lamp manufactured by Hitec Co., Ltd.) was used for this, and an exposure of about 400 mJ was performed. Development was carried out using a 1% sodium carbonate aqueous solution at 30 ° C. for 150 to 200 seconds, followed by washing with pure water. The case where a Via having a diameter of 500 μm could be resolved without roughening the surface was evaluated as ◯, and the case where the Via could not be resolved was evaluated as x.

[Evaluation of warpage]
The warpage was evaluated by using the flexible substrate and the height of the four corners of the substrate. Specifically, a film-like photosensitive resin composition having a film thickness of 25 μm was laminated, exposed and developed under the above conditions on the flexible substrate, and then cured at 160 ° C. for 60 minutes. The obtained insulating film-formed flexible substrate was cut into a 50 mm × 50 mm shape, and the heights of the four corners were measured. A sample having an average height at four corners of less than 5 mm was marked with ◯, and a sample having more than 4 mm was marked with ×.

[Folding resistance test]
The folding resistance test was evaluated by the number of times until the test piece was cut by a 180 ° helical fold test. Specifically, a film-like photosensitive resin composition having a film thickness of 25 μm is laminated on the shine surface side of a copper foil having a thickness of 12 μm (manufactured by Furukawa Circuit Foil Co., Ltd .: F2-WS) under the above conditions, and exposure and development are performed. After curing, all the copper foil was removed by etching. The obtained cured film was cut into a width of 8 mm and a length of 100 mm, and evaluated by the number of times until the test piece was cut in a 180 ° helix test. 10 or more times were marked with ◯, and less than 10 times were marked with x.

[Evaluation of storage stability]
Storage stability was evaluated by photolithography after leaving the film-like photosensitive resin composition at 23 ° C. under light shielding for 2 weeks, and ◯ when the photolithographic property was good and x when it was poor. .

[Evaluation of scratch resistance]
The scratch resistance was evaluated according to JIS K5400 as pencil hardness. Specifically, a photosensitive resin film having a thickness of 25 μm is laminated on the shine surface side of a 12 μm thick copper foil (F2-WS, manufactured by Furukawa Circuit Foil Co., Ltd.) under the above conditions, and exposure, development, and curing are performed. Then, the insulating film surface of the obtained insulating film-forming flexible substrate was rubbed with several kinds of pencils having different hardnesses, and the pencil having the highest hardness among the pencils that were not damaged was defined as the pencil hardness.

[Evaluation of film appearance]
The film appearance was evaluated as the film appearance after the plating treatment. The appearance of the film after the plating treatment was evaluated by visual observation of the glossiness of the resin surface and the presence or absence of foreign matter after the electroless Ni / Au plating treatment. The case where there was no problem in the film appearance was rated as ◯, and the case where problems such as surface roughness were observed was marked as x.

[Evaluation of circuit pollution]
The evaluation of circuit contamination was visually evaluated for the gloss of the Au surface after plating. A sample that is glossy and plated evenly is marked with ◯, and a sample that shows uneven plating or deposits is marked with ×.

[Evaluation of plating penetration]
For evaluation of plating penetration, the width changed from the end surface of the cured resin film after plating was measured, and the amount of erosion of the plating solution was determined.

[Evaluation of migration resistance]
The evaluation of migration resistance was made by using a flexible substrate (Espanex: MC12-20-00CEM manufactured by Nippon Steel Chemical Co., Ltd.) in which a film-like photosensitive resin composition having a film thickness of 25 μm was processed into a line / space = 50 μm / 50 μm. ) Was laminated by a thermocompression-type roll laminator under the conditions of pressure 1 MPa and 80 ° C. The obtained insulation film-forming flexible substrate was continuously applied with a voltage of DC 50 V under the conditions of 85 ° C. and 85% humidity on the two non-conductive wires, and the insulation was maintained for 1000 hours or more. What was conducted was set as x.

[Evaluation of adhesion]
The evaluation of adhesion was performed according to JIS K5400. Specifically, a film-shaped photosensitive resin composition with a film thickness of 25 μm is thermocompression bonded under the conditions of pressure 1 MPa and 80 ° C. on the copper foil surface side of a flexible substrate (Espanex: MC12-20-00CEM manufactured by Nippon Steel Chemical). Lamination was performed using a roll laminator. 100 grids of 1 mm were formed on the insulating film forming surface of the obtained insulating film-forming flexible substrate, and a peeling test was performed using a cellophane tape. The state of peeling of the grid was inspected, and those that did not peel were marked with ◯, and those that were peeled off were marked with ×.

[Evaluation of imidization rate]
The imidation ratio of the siloxane-containing polyamic acid is determined by the infrared absorption spectrum of the ester group-containing polyimide precursor and the ester group-containing polyimide thin film by a transmission method using a Fourier transform infrared spectrophotometer (FT-IR5300 manufactured by JASCO Corporation). By measuring, it was calculated from the absorbance derived from the imide group at 1720 cm ⁻¹ .

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, of course, this invention is not limited to this. The abbreviations used in this example are as described above.

Synthesis example 1
In a reactor equipped with a nitrogen injection tube, 102.2 g (0.317 mol) of benzophenonetetracarboxylic dianhydride (BTDA) was dissolved in 460 g of dimethylacetamide, and the reactor was ice-cooled. 15. A diamine (2,2-divinyl-4,4′-diamino-biphenyl) in which R ₃ in the formula (2) is a direct bond, an amino group is located in the para position, and a vinyl group is located in the meta position. In addition, 0 g (0.063 mol) is added, and in formula (1), R ₁ is —CH ₃ , R ₂ is — (CH ₂ ) ₃ —, n is 8 to 9, and the number average molecular weight is about 840 siloxane diamine ( 200.0 g (0.241 mol) manufactured by Shin-Etsu Silicon Co., Ltd .: KF-8010) was added dropwise over 1 hour under a nitrogen atmosphere. After completion of the dropwise addition, the temperature in the reactor was returned to room temperature and stirred for 5 hours under a nitrogen atmosphere to obtain the intended siloxane-containing polyamic acid resin solution. From the measurement results of GPC (polystyrene standard product conversion), the obtained siloxane-containing polyamic acid had a number average molecular weight of 3.3 × 10 ⁴ and a molecular weight distribution of 2.64. The viscosity of this siloxane-containing polyamic acid resin in dimethylacetamide solution (resin concentration: 40.4 wt%) at 25 ° C. was measured using an E-type viscometer to be 7589 cPa · s.

Synthesis example 2
In a reactor equipped with a nitrogen injection tube, 93.3 g (0.317 mol) of biphenyltetracarboxylic dianhydride (BPDA) was dissolved in 450 g of dimethylacetamide, and the reactor was ice-cooled. To this, 5.0 g (0.021 mol) of 2,2-divinyl-4,4′-diamino-biphenyl was added, and 200.0 g (0.241 mol) of siloxane diamine (manufactured by Shin-Etsu Silicon Co., Ltd .: KF -8010) was added dropwise over 1 hour under a nitrogen atmosphere. After completion of the dropwise addition, the temperature in the reactor was returned to room temperature and stirred for 5 hours under a nitrogen atmosphere to obtain the intended siloxane-containing polyamic acid resin solution.

Synthesis example 3
In a reactor equipped with a nitrogen injection tube, 102.2 g (0.317 mol) of BTDA was dissolved in 450 g of dimethylacetamide, and the reactor was ice-cooled. To this, 252.4 g (0.304 mol) of siloxane diamine (manufactured by Shin-Etsu Silicon Co., Ltd .: KF-8010) was added dropwise over 1 hour in a nitrogen atmosphere. After completion of the dropwise addition, the temperature in the reactor was returned to room temperature and stirred for 5 hours under a nitrogen atmosphere to obtain the intended siloxane-containing polyamic acid resin solution.

Synthesis example 4
In a reactor equipped with a nitrogen injection tube, 102.2 g (0.317 mol) of BTDA was dissolved in 450 g of dimethylacetamide, and the reactor was ice-cooled. To this, 15.0 g (0.063 mol) of 2,2-divinyl-4,4′-diamino-biphenyl and 38.1 g (0.190 mol) of diaminodiphenyl ether (DAPE) were added, and another 50.0 g ( 0.060 mol) of siloxane diamine (manufactured by Shin-Etsu Silicon Co., Ltd .: KF-8010) was added dropwise over 1 hour in a nitrogen atmosphere. After completion of the dropwise addition, the temperature in the reactor was returned to room temperature and stirred for 5 hours under a nitrogen atmosphere to obtain the intended siloxane-containing polyamic acid resin solution.

Example 1
Trimethylolpropane trimethacrylate (manufactured by Nippon Kayaku: SR-350) with respect to the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1 (100 parts by weight as the siloxane-containing polyamic acid resin, hereinafter the same). ) 40 parts by weight and 5 parts by weight of a photoinitiator (Ciba Specialty Chemicals Inc .: CGI124) were blended, and this was applied onto a PET film that had been previously subjected to a release treatment so that the film thickness after drying was 25 μm. And a photosensitive resin film was obtained by drying at 120 ° C. for 10 minutes.

Example 2
It carried out similarly to Example 1 except having mix | blended 0.5 weight part of ATD with respect to the siloxane containing polyamic acid resin solution obtained by the synthesis example 1, and it was set as the photosensitive resin film.

Example 3
In the same manner as in Example 1 except that the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 2 was used instead of the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1, a photosensitive resin film and did.

Example 4
In the same manner as in Example 2 except that the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 2 was used instead of the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1, a photosensitive resin film and did.

Example 5
A photosensitive resin film was obtained in the same manner as in Example 2 except that 20 parts by weight of ATD was added to the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1.

Comparative Example 1
A photosensitive resin film was prepared in the same manner as in Example 1 except that 20 parts by weight of trimethylolpropane trimethacrylate was added to the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1. .

Comparative Example 2
A photosensitive resin film was prepared in the same manner as in Example 2 except that 20 parts by weight of trimethylolpropane trimethacrylate was added to the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1. .

Comparative Example 3
A photosensitive resin film was prepared in the same manner as in Example 1 except that 70 parts by weight of trimethylolpropane trimethacrylate was added to the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1. .

Comparative Example 4
A photosensitive resin film was prepared in the same manner as in Example 2 except that 70 parts by weight of trimethylolpropane trimethacrylate was added to the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1. .

Comparative Example 5
In the same manner as in Example 1 except that the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 3 was used instead of the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1, a photosensitive resin film and did.

Comparative Example 6
In the same manner as in Example 1 except that the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 4 was used instead of the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1, a photosensitive resin film and did.

Reference Example Trimethylolpropane trimethacrylate (manufactured by Nippon Kayaku: SR) with respect to the siloxane-containing polyamic acid resin solution obtained in Synthesis Example 1 (100 parts by weight as the siloxane-containing polyamic acid resin, hereinafter the same). -350) 40 parts by weight and 5 parts by weight of a photopolymerization initiator (manufactured by Ciba Specialty Chemicals Inc .: CGI124) are blended, and the film thickness after drying on a PET film that has been pre-released is 25 μm. And a photosensitive resin film was obtained by drying at 160 ° C. for 10 minutes. When the photolithography performance of the obtained photosensitive resin film was evaluated, development was impossible. The imidation ratio before development of the siloxane-containing polyamic acid resin was 60%.

  For the photosensitive resin films obtained in the above examples and comparative examples, photolithographic performance, warpage after development, folding resistance, room temperature storage stability, pencil hardness, film appearance after plating treatment, circuit contamination, plating penetration, Migration resistance and adhesion were evaluated by the following evaluation methods. Tables 1 and 2 show the blending ratio and the evaluation results of the characteristics. In addition, the part in a table | surface shows a weight part.

Claims (3)

The structural unit represented by the following formula (1) is 30 mol% to 95 mol%, the structural unit represented by the formula (2) is 5 mol% to 70 mol%, and the structural unit represented by the formula (3) is 0 to Photosensitivity obtained by blending 1 to 20 parts by weight of a photopolymerization initiator and 30 to 60 parts by weight of a monofunctional or polyfunctional acrylate as essential components with respect to 100 parts by weight of a siloxane-containing polyamic acid resin containing 50 mol%. A photosensitive resin film obtained by applying and drying a resin composition on a substrate film.

(In the formula, Ar represents a tetravalent tetracarboxylic acid residue obtained by removing a carboxyl group from an aromatic tetracarboxylic acid, R ₁ represents an alkyl group having 1 to 6 carbon atoms or a phenyl group, and R ₂ represents 2 to 2 carbon atoms. 6 represents an alkylene group or a phenylene group, l represents a number of 0 to 10, R ₃ represents a divalent group or a direct bond, R ₄ represents a group represented by CH ₂ ═CH—R ₆ —, R ₆ represents a direct bond, an alkylene group having 1 to 6 carbon atoms, or a phenylene group, and R ₅ represents a divalent diamine residue obtained by removing an amino group from a diamine compound. In general formulas (1) and (2), Except when it is a diamine residue, m, n and o represent the molar ratio of each constituent unit, m is 0.3 to 0.95, n is 0.05 to 0.7 and o. Is in the range of 0 to 0.5.) The photosensitive resin film of Claim 1 in which the photosensitive resin composition contains 0.1-10 weight part of triazine thiol compounds represented by following formula (4) with respect to 100 weight part of siloxane containing polyamic acid resin.

  A photosensitive resin film according to claim 1 or 2 is formed on a circuit board on which a conductor circuit is formed so that a desired portion of the conductor circuit is coated, and then exposed, developed, and cured to be a negative type. A method of manufacturing a circuit board, comprising: forming an insulating film.