JP2010209309A - Photosensitive polyimide, photosensitive polyimide ink composition and insulating film - Google Patents

Abstract

A photosensitive polyimide that can be suitably used as an overcoat material for a flexible wiring board and an interlayer insulating material having excellent heat resistance, electrical characteristics, flexibility, and the like, and is soluble in an organic solvent. A photosensitive polyimide ink composition containing a conductive polyimide, and an insulating film obtained by curing the photosensitive polyimide ink composition.
A reaction between an acid dianhydride component mainly composed of a specific alicyclic tetracarboxylic dianhydride and a diamine component mainly composed of a specific aromatic diamine having two carboxyl groups in the molecule. It is soluble in an organic solvent obtained by adding or reacting a compound having a (meth) acryloyl group to a part of a carboxyl group present in the polyimide to a polyimide synthesized by Photosensitive polyimide, photosensitive polyimide ink and insulating film using the same.
[Selection figure] None

Description

  The present invention relates to a photosensitive polyimide, a photosensitive polyimide ink composition, and an insulating film, and more specifically, suitable as an overcoat material for a flexible wiring board excellent in heat resistance, electrical characteristics, flexibility, and an interlayer insulating material. The present invention relates to a photosensitive polyimide soluble in an organic solvent, a photosensitive polyimide ink composition containing the photosensitive polyimide, and an insulating film formed by curing the photosensitive polyimide ink composition.

  Overcoat materials for flexible wiring boards and interlayer insulation films for multilayer substrates are required to have high heat resistance and insulation properties. In addition, photosensitive heat-resistant materials are required for high density and high integration. It is required to be formed.

  It is said that photosensitive polyimide is used for a protective film for an electronic circuit and a protective film for a semiconductor element in the semiconductor industry, but a polyimide precursor is used accurately. This polyimide precursor is imidized by being applied to the surface of the electronic circuit, the protective film, and the like, then exposed to light, developed, and post-baked at a high temperature. When manufacturing a flexible wiring board or the like, the polyimide ink is dried or imidized due to the fact that the substrate used for the flexible wiring board is a film and that the coating area of the substrate on which the polyimide precursor is applied is wide. During the high-temperature heat treatment for the film, the film as a base material is curled remarkably. Therefore, the polyimide precursor cannot be used for manufacturing the flexible wiring board or the like. For these reasons, photosensitive dry films have been developed. However, assuming continuous production of flexible wiring boards, since the production of photosensitive dry film includes a vacuum laminating step, the photosensitive dry film produced by the production method having such a process is: It is not suitable for continuous production of flexible wiring boards and the like.

  For these reasons, it is preferable to use photosensitive polyimide ink for continuous production of flexible wiring boards. However, in the field where a substrate is manufactured using a photosensitive dry film or a liquid resist, the use of ultrasonic waves at the time of development (Patent Document 1) cannot divert existing manufacturing equipment. There are process problems due to new equipment such as irradiation equipment, and the use of organic solvents (Patent Document 2) is accepted because of environmental problems related to solvent recovery and economic problems due to the expansion of explosion-proof equipment. It is difficult and undesirable. According to Patent Document 1, the “organic solvent-soluble photosensitive polyimide siloxane” described in Patent Document 1 is subjected to an inking process to produce a “photosensitive polyimide siloxane solution composition”. This photosensitive polyimide siloxane solution composition is applied onto, for example, a copper circuit pattern, and after application, the organic solvent is removed and exposed to, "2% aqueous solution of tetraethylammonium hydroxide or sodium borate and diethylene glycol monobutyl ether. As described above, the photosensitive polyimidesiloxane solution composition described in Patent Document 1 is referred to as an aqueous solution, but a developer containing an organic compound is used for the development. Therefore, the photosensitive polyimide siloxane described in Patent Document 1 needs to be treated with a waste liquid containing an organic substance when a flexible wiring board is produced using the photosensitive polyimide siloxane.

  In general, aromatic polyimide is colored yellowish brown and has low transmittance for light having a wavelength of 400 nm or less. At present, an ultraviolet lamp equipped in a commercially available ultraviolet irradiation device emits ultraviolet light mainly having a wavelength of 364 nm. Then, even if the coating film formed with the photosensitive polyimide ink composition containing the aromatic polyimide is irradiated with ultraviolet rays, the photosensitive polyimide ink composition is not sufficiently photocured due to the low light transmittance of the aromatic polyimide. There is. As long as the aromatic polyimide is used, it is necessary to solve the problem of low light transmittance in the aromatic polyimide.

JP-A-10-265571 Japanese Patent Laid-Open No. 9-100350

  The problem of the present invention is that it has excellent solubility in an organic solvent, can be screen-printed, has high sensitivity during photocuring, and can be developed with a weak alkaline aqueous solution containing no organic substance, particularly a sodium carbonate aqueous solution. It is providing the photosensitive polyimide used as the raw material of the photosensitive polyimide ink composition.

  Another object of the present invention is to form a cured film that is excellent in bendability, warpage, solder heat resistance, adhesion, glossiness, and gold plating resistance, and is free from organic substances. It is an object of the present invention to provide a photosensitive polyimide ink composition that can be developed with an aqueous alkali solution, particularly an aqueous sodium carbonate solution.

  Furthermore, another object of the present invention is to provide an insulating film that does not curl because high temperature processing (200 to 400 ° C.) for imidization after development is unnecessary and imidization can be achieved at a low temperature. That is.

Means for solving the problems are as follows:
(1) (a) an acid dianhydride component mainly composed of an alicyclic tetracarboxylic dianhydride represented by the following general formula (1)

（一般式（１）中、Ｒは脂環式テトラカルボン酸二無水物のカルボン酸二無水物残基（但し、シクロヘキサンテトラカルボン酸二無水物のカルボン酸二無水物残基を除く。）である。）
下記一般式（２）で示されるカルボキシル基を分子中に２個有する芳香族ジアミンを全ジアミン成分に対して７０モル％以上の割合で主成分とするジアミン成分、若しくは下記一般式（２）で示される芳香族ジアミンとの反応により合成されるポリイミドに、
(b) 酸二無水物成分が前記一般式（１）で示される脂環式テトラカルボン酸二無水物であるときにはその脂環式テトラカルボン酸二無水物と下記一般式（２）で示されるカルボキシル基を分子中に２個有する芳香族ジアミンを主成分とするジアミン成分との反応により合成されるポリイミドに、
(c) シクロヘキサンテトラカルボン酸二無水物を主成分とする酸二無水物成分と、ジアミン成分が下記一般式（２）で示されるカルボキシル基を分子中に２個有する芳香族ジアミンであるときにはそのジアミン成分との反応により合成されるポリイミドに、又は、
(d) シクロヘキサンテトラカルボン酸二無水物を主成分とする酸二無水物成分と、前記一般式（２）で示されるカルボキシル基を分子中に２個有する芳香族ジアミン、並びに、ジアミノポリシロキサン（ＤＡＰＳ）、ビス４−アミノフェノキシフェニルプロパン（ＢＡＰＰ）、及び３，５−ジアミノ安息香酸（ＤＡＢＡ）のうち少なくとも一つの芳香族ジアミンを含有するジアミン成分との反応により合成されるポリイミドに、
（メタ）アクリロイル基を有する化合物を、前記ポリイミド中に存在するカルボキシル基の一部に付加反応させ、又は、縮合反応させてなる有機溶媒可溶性であることを特徴とする感光性ポリイミドであり、

(In general formula (1), R is a carboxylic dianhydride residue of alicyclic tetracarboxylic dianhydride (excluding a carboxylic dianhydride residue of cyclohexane tetracarboxylic dianhydride). is there.)
A diamine component having as a main component an aromatic diamine having two carboxyl groups represented by the following general formula (2) in the molecule at a ratio of 70 mol% or more with respect to the total diamine component, or the following general formula (2) To the polyimide synthesized by reaction with the aromatic diamine shown,
(b) When the acid dianhydride component is the alicyclic tetracarboxylic dianhydride represented by the general formula (1), the alicyclic tetracarboxylic dianhydride and the following general formula (2) To the polyimide synthesized by the reaction with a diamine component mainly composed of an aromatic diamine having two carboxyl groups in the molecule,
(c) When the acid dianhydride component mainly composed of cyclohexanetetracarboxylic dianhydride and the diamine component are aromatic diamines having two carboxyl groups in the molecule represented by the following general formula (2) To polyimide synthesized by reaction with diamine component, or
(d) an acid dianhydride component composed mainly of cyclohexanetetracarboxylic dianhydride, an aromatic diamine having two carboxyl groups in the molecule represented by the general formula (2), and diaminopolysiloxane ( A polyimide synthesized by a reaction with a diamine component containing at least one aromatic diamine among DAPS), bis-4-aminophenoxyphenylpropane (BAPP), and 3,5-diaminobenzoic acid (DABA);
A compound having a (meth) acryloyl group is an organic solvent-soluble polyimide obtained by addition reaction or condensation reaction with a part of the carboxyl group present in the polyimide,

（但し、一般式（２）中、ＸはＯ、ＣＨ_２、Ｃ（ＣＦ_３）_２、Ｏ−Ｃ_６Ｈ_４−Ｃ（ＣＨ_３）_２−Ｃ_６Ｈ_４−Ｏ、又は直接結合を示す）。
（２） 前記酸二無水物成分が前記一般式（１）で示される脂環式テトラカルボン酸二無水物を前記主成分として含有する場合に、前記酸二無水物成分が芳香族テトラカルボン酸二無水物を含むことを特徴とする前記（１）に記載の感光性ポリイミドであり、
（３） 前記芳香族テトラカルボン酸二無水物は、その含有量が前記酸二無水物成分に対して３５モル％未満である前記（２）に記載の感光性ポリイミドであり、
（４） 前記ジアミン成分が、前記一般式（２）で示される芳香族ジアミン以外の芳香族ジアミンを含むことを特徴とする前記（１）〜（３）のいずれか一つに記載の感光性ポリイミドであり、
（５） 前記ジアミン成分が、ジアミノポリシロキサンを含むことを特徴とする前記（１）〜（４）のいずれか一つに記載の感光性ポリイミドであり、
（６） 前記ジアミノポリシロキサンは、その含有量が前記ジアミン成分に対して４０モル％以下であることを特徴とする前記（５）に記載の感光性ポリイミドであり、
また、前記課題を解決するための他の手段は、
（７） 前記（１）〜（６）のいずれか一つに記載の感光性ポリイミドとこの感光性ポリイミドを溶解することのできる有機溶媒とを含有することを特徴とする感光性ポリイミドインク組成物であり、
（８） 光重合開始剤、増感剤、耐熱性エポキシ樹脂及び無機充填剤を含有することを特徴とする前記（７）に記載の感光性ポリイミドインク組成物であり、
（９） 感光性ポリイミド１００重量部に対して前記（メタ）アクリレート化合物５〜７０重量部、光重合開始剤及び増感剤１〜５０重量部、耐熱性エポキシ樹脂１０〜７０重量部、並びに無機充填剤１０〜８０重量部を含有することを特徴とする前記（８）に記載の感光性ポリイミドインク組成物であり、
また、前記課題を解決するためのその他の手段は、
（１０） 前記（７）〜（９）のいずれか一つに記載の感光性ポリイミドインク組成物を基材に塗布し、プリベークし、露光し、かつ現像した後、ポストベークして成ることを特徴とする絶縁膜である。

(In the general formula (2), X represents O, CH ₂ , C (CF ₃ ) ₂ , O—C ₆ H ₄ —C (CH ₃ ) ₂ —C ₆ H ₄ —O, or a direct bond. ).
(2) When the acid dianhydride component contains the alicyclic tetracarboxylic dianhydride represented by the general formula (1) as the main component, the acid dianhydride component is an aromatic tetracarboxylic acid. The photosensitive polyimide according to (1) above, comprising dianhydride,
(3) The aromatic tetracarboxylic dianhydride is the photosensitive polyimide according to (2), the content of which is less than 35 mol% with respect to the acid dianhydride component,
(4) The photosensitivity as described in any one of (1) to (3) above, wherein the diamine component contains an aromatic diamine other than the aromatic diamine represented by the general formula (2). Polyimide,
(5) The photosensitive diamine according to any one of (1) to (4), wherein the diamine component includes diaminopolysiloxane,
(6) The diaminopolysiloxane is a photosensitive polyimide according to (5), characterized in that the content thereof is 40 mol% or less with respect to the diamine component,
In addition, other means for solving the above-described problems are:
(7) A photosensitive polyimide ink composition comprising the photosensitive polyimide according to any one of (1) to (6) and an organic solvent capable of dissolving the photosensitive polyimide. And
(8) The photosensitive polyimide ink composition according to (7) above, which contains a photopolymerization initiator, a sensitizer, a heat-resistant epoxy resin, and an inorganic filler,
(9) 5 to 70 parts by weight of the (meth) acrylate compound, 1 to 50 parts by weight of a photopolymerization initiator and sensitizer, 10 to 70 parts by weight of a heat-resistant epoxy resin, and inorganic with respect to 100 parts by weight of the photosensitive polyimide. The photosensitive polyimide ink composition as described in (8) above, containing 10 to 80 parts by weight of a filler,
In addition, other means for solving the above problems are as follows:
(10) The photosensitive polyimide ink composition according to any one of (7) to (9) is applied to a substrate, pre-baked, exposed and developed, and then post-baked. The insulating film is characterized.

  The photosensitive polyimide of this invention has excellent solubility in organic solvents. Therefore, the photosensitive polyimide ink composition can be easily prepared by dissolving the photosensitive polyimide in an organic solvent.

  In the photosensitive polyimide ink composition of the present invention, an ultraviolet-exposed portion is easily cured by irradiating a coating film formed from this photosensitive polyimide ink composition with ultraviolet rays having a wavelength of less than 400 nm, and an ultraviolet-unexposed portion. Can be easily removed with a weak alkaline aqueous solution containing no organic compound. Therefore, the photosensitive polyimide ink composition of the present invention can be easily developed with a weak alkaline aqueous solution containing no organic compound after ultraviolet irradiation. Therefore, when producing an insulating film having a predetermined pattern formed on the surface using this photosensitive polyimide ink composition, a special treatment for treating an organic compound-containing waste liquid generated by washing and removing with an organic compound-containing aqueous solution. An insulating film that can be easily manufactured can be provided by using an existing wastewater treatment apparatus as it is and using an existing resist developing machine without particularly installing a waste liquid treatment apparatus.

  In addition, the insulating film of the present invention is sufficiently satisfactory in solder heat resistance in practical use, has adhesiveness to the base material, and does not generate cracks even when the insulating film itself is bent, and has excellent flexibility. Yes.

  In particular, it is formed using a photosensitive polyimide ink composition containing a photosensitive polyimide containing an alicyclic tetracarboxylic dianhydride or manufactured using an acid dianhydride component containing this as a main component. The exposed insulating film has no residue on the substrate exposed by removing the unexposed portion with a weak alkaline aqueous solution containing no organic compound, and the surface of the cured portion cured by exposure has excellent gloss. .

  Furthermore, the photosensitive polyimide ink composition of the present invention, which contains a photosensitive polyimide formed using cyclohexanetetracarboxylic dianhydride, has good light transmission and can be easily exposed by a conventional exposure system. be able to.

  The photosensitive polyimide ink composition of the present invention containing a photosensitive polyimide formed using an alicyclic tetracarboxylic dianhydride is imidized after image formation like a conventional photosensitive polyamic acid. High temperature processing (200 to 400 ° C.) is not required, and heat treatment at about 150 to 180 ° C. is sufficient, so that not only high reliability and low cost but also thermal damage to the substrate is not caused. Therefore, it can be suitably used for manufacturing an insulating film having a negative pattern and a positive pattern.

  Furthermore, the insulating film having a pattern made of a cured film, formed using the photosensitive polyimide ink composition of the present invention, is excellent in solder heat resistance, gold plating resistance, and flexibility. In addition, even if the photosensitive polyimide ink composition of the present invention is a coating film having a thickness of 10 to 30 μm, a cured portion having a line width of about 20 to 50 μm can be formed by light irradiation. It can be evaluated that the photosensitive polyimide ink composition has a high resolving power. Therefore, the photosensitive polyimide ink composition of the present invention is suitable as an insulating film in a high density flexible substrate, BGA, CSP or the like.

The photosensitive polyimide of this invention is
(a) an acid dianhydride component mainly composed of an alicyclic tetracarboxylic dianhydride represented by the following general formula (1):

（一般式（１）中、Ｒは脂環式テトラカルボン酸二無水物のカルボン酸二無水物残基（但し、シクロヘキサンテトラカルボン酸二無水物のカルボン酸二無水物残基を除く。）である。）
下記一般式（２）で示されるカルボキシル基を分子中に２個有する芳香族ジアミンを全ジアミン成分に対して７０モル％以上の割合で主成分とするジアミン成分、若しくは下記一般式（２）で示される芳香族ジアミンとの反応により合成されるポリイミドに、
(b) 酸二無水物成分が前記一般式（１）で示される脂環式テトラカルボン酸二無水物であるときにはその脂環式テトラカルボン酸二無水物と下記一般式（２）で示されるカルボキシル基を分子中に２個有する芳香族ジアミンを主成分とするジアミン成分との反応により合成されるポリイミドに、
(c) シクロヘキサンテトラカルボン酸二無水物を主成分とする酸二無水物成分と、ジアミン成分が下記一般式（２）で示されるカルボキシル基を分子中に２個有する芳香族ジアミンであるときにはそのジアミン成分との反応により合成されるポリイミドに、又は、
(d) シクロヘキサンテトラカルボン酸二無水物を主成分とする酸二無水物成分と、前記一般式（２）で示されるカルボキシル基を分子中に２個有する芳香族ジアミン、並びに、ジアミノポリシロキサン（ＤＡＰＳ）、ビス４−アミノフェノキシフェニルプロパン（ＢＡＰＰ）、及び３，５−ジアミノ安息香酸（ＤＡＢＡ）のうち少なくとも一つの芳香族ジアミンを含有するジアミン成分との反応により合成されるポリイミドに、
（メタ）アクリロイル基を有する化合物を、前記ポリイミド中に存在するカルボキシル基の一部に付加反応させ、又は、縮合反応させることにより得ることができる。

(In general formula (1), R is a carboxylic dianhydride residue of alicyclic tetracarboxylic dianhydride (excluding a carboxylic dianhydride residue of cyclohexane tetracarboxylic dianhydride). is there.)
A diamine component having as a main component an aromatic diamine having two carboxyl groups represented by the following general formula (2) in the molecule at a ratio of 70 mol% or more with respect to the total diamine component, or the following general formula (2) To the polyimide synthesized by reaction with the aromatic diamine shown,
(b) When the acid dianhydride component is the alicyclic tetracarboxylic dianhydride represented by the general formula (1), the alicyclic tetracarboxylic dianhydride and the following general formula (2) To the polyimide synthesized by the reaction with a diamine component mainly composed of an aromatic diamine having two carboxyl groups in the molecule,
(c) When the acid dianhydride component mainly composed of cyclohexanetetracarboxylic dianhydride and the diamine component are aromatic diamines having two carboxyl groups in the molecule represented by the following general formula (2) To polyimide synthesized by reaction with diamine component, or
(d) an acid dianhydride component composed mainly of cyclohexanetetracarboxylic dianhydride, an aromatic diamine having two carboxyl groups in the molecule represented by the general formula (2), and diaminopolysiloxane ( A polyimide synthesized by a reaction with a diamine component containing at least one aromatic diamine among DAPS), bis-4-aminophenoxyphenylpropane (BAPP), and 3,5-diaminobenzoic acid (DABA);
A compound having a (meth) acryloyl group can be obtained by addition reaction or condensation reaction with a part of the carboxyl groups present in the polyimide.

（但し、一般式（２）中、XはO、CH₂、C(CF₃)₂、O−C₆H₄−C(CH₃)₂−C₆H₄−O、又は直接結合を示す。）

(In the general formula (2), X represents O, CH ₂ , C (CF ₃ ) ₂ , O—C ₆ H ₄ —C (CH ₃ ) ₂ —C ₆ H ₄ —O, or a direct bond. .)

  Examples of the alicyclic tetracarboxylic dianhydride represented by the general formula (1) in the present invention include bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic acid dihydrate. Anhydride (BTA), 2,3,5-tricarboxycyclopentyl acetic dianhydride (2,3,5-Tricarboxycyclopentylacetic Dianhydride, TCDA), 2,2-bis [4- (3,4-dicarboxycyclohexyloxy) Group consisting of phenylpropanoic dianhydride, 3,3 ′, 4,4′-bicyclohexyltetracarboxylic dianhydride (HBPDA), cyclohexanetetracarboxylic dianhydride (hexahydropyromellitic anhydride, HPMDA), etc. At least one or two selected from can be preferably used. Among these, as the acid dianhydride component, for example, a photosensitive polyimide obtained by using 3,3 ′, 4,4′-bicyclohexyltetracarboxylic dianhydride (HPMDA) is a photosensitive polyimide ink composition. In this case, the remaining amount of unexposed residue adhering to the substrate surface after development is extremely reduced, and a cured film having excellent gloss is formed.

  The acid dianhydride component in this invention may be an alicyclic tetracarboxylic dianhydride itself, and contains an alicyclic tetracarboxylic dianhydride as a main component. As the remaining component in the acid dianhydride component mainly composed of alicyclic tetracarboxylic dianhydride, aromatic tetracarboxylic dianhydride is used as long as the solubility of the photosensitive polyimide in an organic solvent is not impaired. Can be included. Examples of aromatic tetracarboxylic dianhydrides that can be used in combination include 4,4′-oxydiphthalic dianhydride (ODPA) and 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propanoic acid. An anhydride, and 3,3 ', 4,4'-biphenyl tetracarboxylic dianhydride etc. can be mentioned. The amount of the aromatic tetracarboxylic dianhydride used in combination is preferably less than 35 mol%, particularly preferably less than 25 mol%, relative to the acid anhydride component. If the amount of aromatic tetracarboxylic dianhydride used is greater than or equal to the above value, the solubility of the resulting photosensitive polyimide in an organic solvent is reduced, and / or insulation obtained by exposing the photosensitive polyimide ink composition. Inconveniences such as hindering the transparency of the film may occur.

  The aromatic diamine represented by the general formula (2) in the present invention includes 5,5′-methylenebis [2-aminobenzoic acid] (MBA) and 5,5′-oxybis [2-aminobenzoic acid]. 2,2-bis [4- (2-aminohydrophenylcarboxylic acid) phenyl] propane, 1,3-trifluoro-2,2-bis [4- (2-aminohydrophenylcarboxylic acid) phenyl] propane, and the like Is preferably used.

  The diamine component in the present invention may be the aromatic diamine itself represented by the general formula (2), or the aromatic having one COOH group bonded to two benzene rings each having an amino group in the molecule. Along with the diamine, an aromatic diamine having no COOH group bonded to two benzene rings having an amino group in the molecule can be used in combination. Examples of aromatic diamines having no COOH group bonded to the benzene ring include 4,4′-diaminodiphenyl (HAB), 3,3′-dihydroxy 4,4′-diaminobiphenyl, and 4,4′-dihydroxy-3, 3'-diaminobiphenyl, 4,4'-dihydroxy-3,3'-diaminodiphenyl ether, 3,3'-dihydroxy-4,4'-diaminodiphenyl sulfoxide, 3,3'-dihydroxy-4,4'-diamino Diphenylsulfone, 1,1′-bis [4- (3-hydroxy-4-aminophenoxy) phenyl] methane, 1,3′-bis (3-hydroxy-4-aminophenoxy) benzene, bis [4- (3 -Hydroxy-4-aminophenoxy) phenyl] sulfone, and 2,2′-bis (3-amino-4-hydroxyphenyl) hexafluoropro Aromatic diamines having two benzene rings such as benzene (BAFA), 4,4′-diaminodiphenyl ether, 4,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylsulfone, and o-tolidine, Aromatic diamines having three benzene rings such as bis (4-aminophenoxy) benzene and 1,3-bis (4-aminophenoxy) benzene, and bis [4- (4-aminophenoxy) phenyl] sulfone, And aromatic diamines having four benzene rings such as 2,2-bis [4- (4-aminophenoxy) phenyl] propane. The ratio of the aromatic diamine having no COOH group bonded to the benzene ring to the diamine component is preferably less than 20 mol%, particularly preferably less than 10 mol%, based on the diamine component. When the amount of the aromatic diamine having no COOH group bonded to the benzene ring is 20 mol% or more, development with a weak alkaline aqueous solution containing no organic compound may not be performed.

  A diamine component can also be used individually by 1 type, and can also use 2 or more types together.

  The photosensitive polyimide of this invention comprises the alicyclic tetracarboxylic dianhydride and an equimolar amount of 1 to several diamine components with respect to the acid dianhydride component, for example, at a temperature of 80 ° C. or less. Preferably, a polyamic acid solution is produced by a random polymerization reaction or a block polymerization reaction taking about 1 to 24 hours, for example, at 10 to 70 ° C., followed by further raising the temperature to a lower temperature than conventional, for example, 140 to 200 ° C. After performing an imidization reaction taking about 1 to 3 hours to produce a solution containing polyimide, a compound having a (meth) acryloyl group is added to the carboxylic acid bonded in the polyimide. It can obtain suitably.

  Examples of the compound having a (meth) acryloyl group include organic compounds having a glycidyl group and a (meth) acryloyl group having addition reactivity or condensation reactivity with respect to a COOH group, such as glycidyl methacrylate, glycidyl acrylate, and glycidyl poly. Examples thereof include siloxymethacrylate and a (meth) acryloyl compound having one epoxy group (for example, trade name: vinyl ester resin Lipoxy 630X-501 manufactured by Showa Polymer Co., Ltd.).

  Examples of the organic solvent in the above polymerization reaction, imidation reaction, and addition reaction of a compound having a (meth) acryloyl group include N, N-dimethylsulfoxide, N, N-dimethylformamide, N, N-dimethylacetamide, N , N-diethylacetamide, N-methyl-2-pyrrolidone, hexamethylphosphoric triamide and the like are used.

  The photosensitive polyimide of the present invention is obtained after completion of the reaction, and a photosensitive polyimide solution containing a photosensitive polyimide may be used as it is. However, depending on the application, the photosensitive polyimide isolated from the photosensitive polyimide solution may be used. You may use the photosensitive polyimide containing solution which melt | dissolved the polyimide in the organic solvent.

  The photosensitive polyimide ink composition of the present invention is preferably a composition obtained by preparing a photosensitive polyimide to a solid content concentration of 20 to 50% by weight. A suitable photosensitive polyimide ink composition may contain, in addition to the photosensitive polyimide, a photopolymerization initiator, a sensitizer, a thixotropy imparting agent, an antifoaming agent, a curing agent, and a heat-resistant auxiliary agent. The photosensitive polyimide ink composition may contain a (meth) acryloyl group-containing photocrosslinking agent as long as the properties of the insulating film after photocuring are not impaired.

  Examples of the photopolymerization initiator and sensitizer include Michler's ketone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin propyl ether, 2-t-butylanthraquinone, 1,2-benzo-9,10-anthraquinone, 4,4 '-Bis (diethylamino) benzophenone, acetophenone, thioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone, [4- (methylphenylthio) phenyl] phenylmethane, p-dimethylaminobenzoic acid isoamyl ester, p-dimethylamino Benzoic acid ethyl ester, 1,5-acenaphthene, 1-hydroxy-cyclohexyl phenyl ketone, 2-benzyl-1,2-dimethylamino-1- (4-morpholinophenyl) butane-1,1-hydroxy-cyclo It may be mentioned cyclohexyl phenyl ketone. The content of the photopolymerization initiator and the sensitizer in the photosensitive polyimide ink composition is a total of the photopolymerization initiator and the sensitizer, and is 1 to 30 parts by weight, particularly 100 parts by weight of the photosensitive polyimide. 2 to 15 parts by weight is preferred.

  Examples of the crosslinking agent include trimethylolpropane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate, and phosphoric acid (meth) acrylate. The addition amount is preferably 30 parts by weight or less, particularly preferably 15 parts by weight or less with respect to 100 parts by weight of the photosensitive polyimide.

  A heat-resistant epoxy resin etc. can be mentioned as a suitable example as said hardening | curing agent. As the heat resistant epoxy resin, O-cresol novolac type epoxy resin and biphenol type epoxy resin are suitable. The content of the heat-resistant epoxy resin in the photosensitive polyimide ink composition is 3 to 20 parts by weight, particularly 5 to 5 parts by weight with respect to 100 parts by weight of the photosensitive polyimide in consideration of the acid value of the photosensitive polyimide and the compatibility with the organic solvent. 10 parts by weight is preferred.

  Further, in the photosensitive polyimide ink composition of the present invention, a fine thixotropy imparting agent such as aerosil, mica, talc, barium sulfate, and wollastonite and a heat-resistant auxiliary agent are added in an amount of 1 to 10 with respect to 100 parts by weight of the photosensitive polyimide. It is preferable to contain in the ratio of a weight part. This photosensitive polyimide ink composition may further contain a dye and / or a pigment. By containing these dyes and / or pigments, the photosensitive polyimide ink composition can be colored colorless, yellow, blue and green.

  When a slurry mixture obtained by adding various compounds such as the crosslinking agent, curing auxiliary agent, and photoinitiator to the photosensitive polyimide solution of the present invention is kneaded with a kneading apparatus such as a three-roller to form an ink, A polyimide ink composition is prepared. This photosensitive polyimide ink composition is adjusted to viscosity as necessary, applied to a substrate by screen printing or a roll coater, and then pre-baked to make it tack-free. The thickness of the coating film formed by the coating is usually 5 to 50 μm, preferably 10 to 30 μm. The heating temperature when pre-baking the coating film in a tack-free state is 90 ° C. or lower, preferably 40 to 80 ° C. A negative photomask is brought into close contact with the surface of the pre-baked and dried coating film, and ultraviolet rays are irradiated from the photomask side toward the coating film. Subsequently, the pattern formed with the hardening body of the photosensitive polyimide ink composition can be obtained by washing away an unexposed part with a developing solution using a shower, and preferably further post-baking. The developer is a weak alkaline aqueous solution containing no organic compound. Examples of the weak alkaline aqueous solution containing no organic compound include an aqueous solution obtained by dissolving caustic soda, caustic potash, sodium carbonate, and the like.

Example 1
(Synthesis of photosensitive polyimide)
Bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BTA) 14.89 g and oxydiphthalic dianhydride (ODPA) 9.31 g are mixed with N- After dissolving in 50.0 g of methyl-2-pyrrolidone (NMP), 25.77 g of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) was added at room temperature, and then reacted at 180 ° C. for 2 hours. After 2 hours, 11.37 g of glycidyl methacrylate was added at a temperature of 100 ° C. and reacted for 0.5 hour to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
To 55 g of the photosensitive polyimide solution, 0.6 g of 2,4-diethylthioxanthone as a photopolymerization initiator, 1.1 g of ethyl dimethylaminobenzoate, 4.5 g of trimethylolpropane triacrylate, 1.0 g of aerosil, barium sulfate 1 0.5 g and 1.7 g of a biphenol type epoxy resin were added, and the resulting mixture was kneaded with three rolls to obtain a photosensitive polyimide ink composition. The monomer composition and its molar ratio in this photosensitive polyimide are shown in Table 1, and the characteristics of the coating film formed using the photosensitive polyimide ink composition are evaluated as follows. The evaluation results are shown in Table 2. Show.

(Characteristic evaluation of coating film)
1. Solubility of coating film A photosensitive polyimide ink composition was printed on a copper-clad laminate with a 200-mesh screen plate, pre-baked for 30 minutes while heating to 80 ° C., and then a negative pattern was vacuum-adhered to obtain ORC HMW 680C. An ultraviolet ray having a wavelength of 365 nm was irradiated at an intensity of 400 mJ / cm ² with an exposure machine incorporating a metal halide lamp. Next, spraying 1 kgf / cm ² from a distance of 15 cm with a 1% aqueous solution of sodium carbonate heated to 30 ° C. for 1 minute results in no polyimide coating remaining on the unexposed area and a cured pattern in the exposed area. ◎ that the corners in the vertical cross section are good without being rounded, ◎, the corner of the cured pattern is round and poorly cut ○, some uncured photosensitive polyimide remains △, and the case where all of the uncured polyimide coating film remained was evaluated as x.

2. Bending property A photosensitive polyimide ink composition is applied to a 15 μm copper foil, pre-baked for 30 minutes while being heated to 80 ° C., and then an ultraviolet ray having a wavelength of 365 nm is applied at an intensity of 400 mJ / cm ² with an exposure machine with a built-in metal halide lamp. Irradiated. Subsequently, the film was post-baked for 60 minutes while being heated to 150 ° C., and the coating film was turned outward and folded inward by 180 degrees. No change in the coating film on the bent line is evaluated as ◯, some fine scratches are judged as having no problem in practical use, ○ ⁻ , and cracks as a whole are evaluated as ×. did.

3. Warpability A photosensitive polyimide ink composition was applied on the surface of a 50 mm square polyimide film having a thickness of 12.5 μm, prebaked for 30 minutes while being heated to 80 ° C., and then exposed to a wavelength of 365 nm with an exposure machine with a built-in metal halide lamp. As a result of irradiating ultraviolet rays of 400 mJ / cm ² and then post-baking for 60 minutes while further heating to 150 ° C., a film having a warp of 5 mm or less and a warp of 6 to 10 mm ○ ^- , and a warp exceeding 10 mm was evaluated as x.

4). Solder heat resistance A photosensitive polyimide ink composition is screen-printed on a copper clad laminate, pre-baked, irradiated with ultraviolet light at 400 mJ / cm ² , heated at 150 ° C. for 60 minutes, and then flux is applied to the surface. The surface was floated and brought into contact with the solder melting surface at 260 ° C. for 10 seconds. As a result, it was evaluated as “◯” when no swelling, peeling or discoloration of the coating film was observed, “Δ” when the coating film was somewhat recognized, and “X” when the coating film flowed, swollen or discolored.

5). Adhesiveness A tape that is cross-cut for each of the coating film after post-baking and the coating film after contacting the solder melt surface when evaluating the “solder heat resistance” and adhered to the cross-cut surface ( (Registered trademark) was evaluated by peeling. The case where none of the grids formed by cross-cutting was peeled was evaluated as ◯, and the case where even one of the grids was peeled off was evaluated as x.

(Example 2)
(Synthesis of photosensitive polyimide)
6.2 g of oxydiphthalic dianhydride (ODPA) and diaminopolysiloxane (KF-8010 manufactured by Shin-Etsu Chemical Co., Ltd.) (amino equivalent 410) (DAPS) 8.2 g of N-methyl-2-pyrrolidone (NMP) 36. Dissolved in 4 g, heated to 180 ° C. and reacted for 2 hours. Subsequently, at room temperature, 14.31 g of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) and bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic acid Anhydrous (BTA) 9.93 g was sequentially added and then reacted at 180 ° C. for 2 hours. After 2 hours, 1.6 g of glycidyl methacrylate was added at a temperature of 100 ° C. and reacted for 0.5 hour to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
A photosensitive polyimide ink composition was prepared from the photosensitive polyimide solution in the same manner as in Example 1, and evaluated. The monomer composition in the photosensitive polyimide is shown in Table 1, and the evaluation of the coating film formed using the photosensitive polyimide ink composition is performed in the same manner as in the above Examples. The evaluation results are shown in Table 2.

Example 3
(Synthesis of photosensitive polyimide)
Bicyclo [2.2.2] octo-7-ene-2,3,5,6-tetracarboxylic dianhydride (BTA) 12.41 g N-methyl 7-2-pyrrolidone (NMP) 35.3 g In addition, dissolved in this, 8.59 g of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) and 4.32 g of 3,3′-dihydroxy 4,4′-diaminodiphenyl (HAB) were added. And reacted for 2 hours while heating to 180 ° C. Next, 8.20 g of glycidyl methacrylate was added and reacted for 0.5 hour while heating to 100 ° C. to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
A photosensitive polyimide ink composition was prepared from the photosensitive polyimide solution in the same manner as in Example 1, and evaluated. The monomer composition in the photosensitive polyimide is shown in Table 1, and the evaluation of the coating film formed using the photosensitive polyimide ink composition is performed in the same manner as in the above Examples. The evaluation results are shown in Table 2.

Example 4
(Synthesis of photosensitive polyimide)
To 11.21 g of 2,3,5-tricarboxycyclopentylacetyl dianhydride (TCDA), 34.5 g of N-methyl 7-2-pyrrolidone (NMP) was added and dissolved, and 5,5′-methylenebis [2-amino Benzoic acid] (MBA) 8.59 g and 3,3′-hydroxy 4,4′-diaminodiphenyl (HAB) 4.32 g were added and reacted at 180 ° C. for 2 hours. Next, 8.5 g of glycidyl methacrylate was added at a temperature of 100 ° C. and reacted for 0.5 hours to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
A photosensitive polyimide ink composition was prepared from the photosensitive polyimide solution in the same manner as in Example 1, and the same evaluation as in Example 1 was performed. The monomer composition in the photosensitive polyimide is shown in Table 1, and the evaluation results regarding the photosensitive polyimide ink composition are shown in Table 2.

(Comparative Example 1)
A photosensitive polyimide ink composition was prepared in the same manner as in Example 1 except that oxydiphthalic dianhydride (ODPA) was not used. However, the ultraviolet irradiation part was also dissolved in the aqueous sodium carbonate solution, and no photocuring characteristics could be found. Therefore, the symbol of evaluation could not be described in Table 2.

(Comparative Example 2)
Oxydiphthalic dianhydride using 2,2′-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (BAFA) instead of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) A photosensitive polyimide ink composition was prepared in the same manner as in Example 1 except that (ODPA) was not used. However, the unexposed portion was insoluble in the sodium carbonate aqueous solution, and the photocuring characteristics could not be measured. Therefore, the symbol of evaluation could not be described in Table 2.

(Comparative Example 3)
A photosensitive polyimide was prepared in the same manner as in Example 1 except that 3,5-diaminobenzoic acid (DABA) was used instead of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) in Example 1. An ink composition was prepared. However, the unexposed portion was insoluble in the sodium carbonate aqueous solution, and the photocuring characteristics could not be measured. Therefore, the symbol of evaluation could not be described in Table 2.

(Comparative Example 4)
A photosensitive polyimide ink composition was prepared in the same manner as in Example 1, except that one third of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) was replaced with diaminodiphenyl ether (DADE). However, the unexposed portion was insoluble in the sodium carbonate aqueous solution, and the photocuring characteristics could not be measured. Therefore, the symbol of evaluation could not be described in Table 2.

BTA: bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride TCDA: 2,3,5-tricarboxycyclopentylacetic acid dianhydride ODPA: 4,4 '-Oxydiphthalic dianhydride MBA: 5,5'-methylenebis [2-aminobenzoic acid]
BAFA: 2,2′-bis (3-amino-4-hydroxyphenyl) hexafluoropropane DABA: 3,5-diaminobenzoic acid DAPS: diaminopolysiloxane HAB: 3,3′-hydroxy 4,4′-diaminodiphenyl DADE: Diaminodiphenyl ether

(Example 5)
A photosensitive polyimide ink composition was prepared in the same manner as in Example 1 except that talc was used instead of barium sulfate. The result was also good.

(Example 6)
(Synthesis of photosensitive polyimide)
24.82 g of bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BTA) was dissolved in 105 g of N-methyl-2-pyrrolodon (NMP), To the obtained solution, 31.16 g of diaminopolysiloxane (amino equivalent 410) (DAPS) was injected, and the reaction was performed for 2 hours while heating to 180 ° C. after the injection. Next, the temperature was returned to room temperature, 17.75 g of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) was added, and the mixture was reacted at 180 ° C. for 2 hours. Next, 7.1 g of glycidyl methacrylate was injected at a temperature of 100 ° C. and reacted for 0.5 hour to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
To 100 parts by weight of the above-mentioned photosensitive polyimide solution, 2 parts by weight of photopolymerization initiator 2,4-diethylthioxanthone, 4 parts by weight of isoamyl p-dimethylaminobenzoate, 15 parts by weight of trimethylolpropane triacrylate, biphenol type epoxy resin YX4000HK6 A photosensitive polyimide ink composition was prepared by adding 5 parts by weight, 5 parts by weight of barium sulfate, and 1 part by weight of a defoaming agent, and kneading with three rolls.

  The following evaluation was performed using the photosensitive polyimide ink composition obtained as described above.

(Sensitivity and resolution)
The photosensitive polyimide ink composition was printed on a copper-clad laminate with a 200-mesh screen plate, and the obtained printed matter was left to dry for 30 minutes in a hot air circulation type constant temperature dryer maintained at 80 ° C. Negative type test pattern films with various pattern diameters are vacuum-contacted to the 13 μm thick film on the printed matter, and from the negative type test pattern film side with an exposure machine with ORC HMW 680C metal halide lamp at a wavelength of 365 nm and 400 mJ / cm ² UV rays were irradiated. After UV irradiation, the negative test pattern film is removed, and the exposed coating film is sprayed with a 1% sodium carbonate aqueous solution kept at 30 ° C. at a spraying pressure of 1 kgf / cm ² for 1 minute from a distance of 15 cm from the coating surface. Further, rinsing was performed by spraying 30 ° C. hot water. After rinsing, when dried and observed, it was confirmed that the ultraviolet-irradiated portion was cured, and the unexposed portion of the ultraviolet ray was washed away and had a well-cut 150 μm circular opening.

(Bendability)
The bendability was evaluated in the same manner as described in the property evaluation column of the coating film. The evaluation result was ◯, and no crack or peeling of the coating film occurred on the bent line.

(Warpage)
The warpage was evaluated in the same manner as described in the property evaluation column of the coating film. The evaluation result was (circle) and the curvature of the film was 4-5 mm.

(Solder heat resistance)
The solder heat resistance was evaluated in the same manner as described in the property evaluation column of the coating film. The evaluation result was ○, and no blistering, peeling, or discoloration of the coating film was observed.

(Adhesion)
Adhesion was evaluated in the same manner as described in the property evaluation column of the coating film. The evaluation result was ○, and peeling of the coating film was not recognized.

(Gold plating resistance)
The photosensitive polyimide ink composition was printed on a copper-clad laminate with a 200-mesh screen plate, pre-baked at 80 ° C. for 30 minutes, and then a negative test pattern film was vacuum-adhered to a 13 μm-thick coating film, and ORC HMW 680C Using an exposure machine with a built-in metal halide lamp irradiated with 400mJ / cm ^{2 of} 365nm UV light, spray developed with 30% 1% sodium carbonate aqueous solution and baked at 150 ° C for 60 minutes. Then, a plating test was conducted.

  When working according to the usage method of ICP Nicolon GM (Okuno Pharmaceutical Co., Ltd. electroless nickel plating solution), the nickel coating was cut well without the coating film being attacked.

  Usually, gold plating is formed on the surface of Ni plating formed on the surface of a base material or a raw material. The pretreatment liquid and plating liquid used for performing Ni plating have stronger acidity than the processing liquid and plating liquid used for gold plating. Therefore, if Ni plating can be performed without problems, gold plating can also be performed without problems. By being able to perform good Ni plating as described above, Ni plating is formed on the surface of the cured product formed by exposing the coating film formed using the photosensitive polyimide ink composition to ultraviolet rays. It can be concluded that the gold plating can be performed well.

(Example 7)
(Synthesis of photosensitive polyimide)
13.45 g of cyclohexanetetracarboxylic dianhydride (HPMDA) and 4.65 g of 4,4′-oxydiphthalic dianhydride (ODPA) are dissolved in 33 g of N-methyl-2-pyrrolidone, and 5.5 ′ at room temperature. -21.47 g of methylenebis [2-aminobenzoic acid] (MBA) was added and then maintained at room temperature for 2 hours. Then, it was made to react at 180 degreeC for 2 hours. After completion of the reaction, 10.67 g of glycidyl methacrylate was added at 100 ° C. and reacted for 0.5 hour to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
A photosensitive polyimide ink composition was obtained in the same manner as in Example 1 except that the photosensitive polyimide solution was used instead of the photosensitive polyimide solution described in Example 1. Table 3 shows the monomer composition and molar ratio of the photosensitive polyimide contained in this photosensitive polyimide ink composition, and Table 4 shows the evaluation results regarding the photosensitive polyimide ink composition.

  In addition, evaluation regarding this photosensitive polyimide ink composition was performed as follows.

(Characteristic evaluation of coating film)
1. Outside was irradiated with ultraviolet rays of 600 mJ / cm ² instead of irradiation with ultraviolet rays of soluble 400 mJ / cm ² of the coating film was evaluated for dissolution of the coating in the same manner as in Example 1.

2. Bendability The bendability was evaluated in the same manner as in Example 1.

3. Warpage property The warpage property was evaluated in the same manner as in Example 1.

4). Outside was irradiated with ultraviolet rays of 600 mJ / cm ² ultraviolet instead of irradiating the solder heat resistance UV at an intensity of 400 mJ / cm ² was evaluated for solder heat resistance of the coating film in the same manner as in Example 1 .

5). Adhesiveness The adhesiveness was evaluated in the same manner as in Example 1.

6). Glossiness Regarding the coating film after the post-baking, the surface having a gloss was evaluated as “◯”, and the film having no gloss was evaluated as “X”.

(Example 8)
(Synthesis of photosensitive polyimide)
17.93 g of cyclohexanetetracarboxylic dianhydride (HPMDA) and 6.20 g of 4,4′-oxydiphthalic dianhydride (ODPA) were dissolved in 48 g of N-methyl-2-pyrrolidone, and 5,5′-methylenebis [2-aminobenzoic acid] (MBA) (17.18 g) and diaminopolysiloxane (KF-8010, Shin-Etsu Chemical Co., Ltd.) (DAPS) (33.20 g) were added, and the mixture was added at room temperature for 1 hour and then at 180 ° C for 2 hours. Reacted. Next, the temperature was lowered to 100 ° C., 8.53 g of glycidyl methacrylate was added and reacted for 0.5 hour to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
A photosensitive polyimide ink was prepared from the above photosensitive polyimide solution in the same manner as in Example 7, and the same evaluation as in Example 7 was performed. Table 3 shows the monomer composition and molar ratio of the photosensitive polyimide contained in this photosensitive polyimide ink composition, and Table 4 shows the evaluation results regarding the photosensitive polyimide ink composition.

Example 9
(Synthesis of photosensitive polyimide)
8.96 g of cyclohexanetetracarboxylic dianhydride (HPMDA) and 12.41 g of bicyclohexyltetracarboxylic dianhydride (HBPDA) were dissolved in 30 g of N-methyl-2-pyrrolidone, and 5,5′-methylenebis [2 -Aminobenzoic acid] (MBA) 20.04 g and bis 4-aminophenoxyphenylpropane (BAPP) 4.10 g were added and reacted at room temperature for 1 hour and at 180 ° C. for 2 hours. Next, the temperature was lowered to 100 ° C., 8.53 g of glycidyl methacrylate was added and reacted for 30 minutes to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
A photosensitive polyimide ink composition was prepared from the above photosensitive polyimide solution in the same manner as in Example 7, and the same evaluation as in Example 7 was performed. Table 3 shows the monomer composition and molar ratio of the photosensitive polyimide contained in this photosensitive polyimide ink composition, and Table 4 shows the evaluation results regarding the photosensitive polyimide ink composition.

(Example 10)
(Synthesis of photosensitive polyimide)
17.93 g of cyclohexanetetracarboxylic dianhydride (HPMDA) and 5.88 g of biphenyltetracarboxylic dianhydride (BPDA) are dissolved in 48 g of N-methyl-2-pyrrolidone, and 5,5′-methylenebis [2- Aminobenzoic acid] (MBA) 18.60 g and 3,5-diaminobenzoic acid (DABA) 5.32 g were added and reacted at room temperature for 1 hour and at 180 ° C. for 2 hours. Next, the temperature was lowered to 100 ° C., 8.53 g of glycidyl methacrylate was added and reacted for 30 minutes to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink composition)
A photosensitive polyimide ink composition was prepared from the above photosensitive polyimide solution in the same manner as in Example 7, and the same evaluation as in Example 7 was performed. Table 3 shows the monomer composition and molar ratio of the photosensitive polyimide contained in this photosensitive polyimide ink composition, and Table 4 shows the evaluation results regarding the photosensitive polyimide ink composition.

(Example 11)
In Example 7, bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BTA) was used instead of cyclohexanetetracarboxylic dianhydride (HPMDA). In the same manner as in Example 7, a photosensitive polyimide ink composition prepared using a photosensitive polyimide solution obtained in the same manner as in Example 7 was formed to form a coating film in the same manner as in Example 7. Was evaluated. Table 3 shows the monomer composition and molar ratio of the photosensitive polyimide contained in this photosensitive polyimide ink composition, and Table 4 shows the evaluation results regarding the photosensitive polyimide ink composition. In particular, the pattern cut after development was inferior and the coating film was not glossy.

Example 12
Bicyclo [2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (BTA) was used in place of cyclohexanetetracarboxylic dianhydride (HPMDA) in Example 8. The photosensitive polyimide is considered to be improved in solubility in sodium carbonate water by carrying out in the same manner as in Example 8 except that the composition ratio of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) is increased. A photosensitive polyimide ink composition was prepared in the same manner as in Example 8 using this photosensitive polyimide solution. Table 3 shows the monomer composition and molar ratio of the photosensitive polyimide contained in this photosensitive polyimide ink composition, and Table 4 shows the evaluation results regarding the photosensitive polyimide ink composition. In particular, the unexposed portion was somewhat poorly developed with an aqueous sodium carbonate solution, and the gloss of the coated film after photocuring was inferior.

(Comparative Example 5)
A photosensitive polyimide ink composition was used in the same manner as in Example 7 except that 3,5-diaminobenzoic acid (DABA) was used instead of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) in Example 7. A product was prepared. Table 3 shows the monomer composition and molar ratio of the photosensitive polyimide contained in this photosensitive polyimide ink composition, and Table 4 shows the evaluation results regarding the photosensitive polyimide ink composition. In particular, the unexposed portion was insoluble in the sodium carbonate aqueous solution, and the photocuring characteristics could not be measured.

(Comparative Example 6)
A photosensitive polyimide ink composition was prepared in the same manner as in Example 7 except that one third of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) was replaced with diaminodiphenyl ether in Example 7. Table 3 shows the monomer composition and molar ratio of the photosensitive polyimide contained in this photosensitive polyimide ink composition, and Table 4 shows the evaluation results regarding the photosensitive polyimide ink composition. In particular, the unexposed portion was insoluble in the sodium carbonate aqueous solution, and the photocuring characteristics could not be measured.

(Example 13)
In preparing a photosensitive polyimide ink composition using the photosensitive polyimide synthesized in Example 7, a photosensitive polyimide ink composition was prepared in the same manner as in Example 7 except that talc was used instead of barium sulfate. did. When this curable polyimide ink composition was used to form a coating film in the same manner as in Example 7, the property results of the cured coating film were as good as in Example 7.

(Example 14)
(Synthesis of photosensitive polyimide)
Diaminopolysiloxane (Shin-Etsu Chemical) was dissolved in 17.93 g of cyclohexanetetracarboxylic dianhydride (HPMDA) and 6.20 g of biphenyltetracarboxylic dianhydride (BPDA) in 45 g of N-methyl-2-pyrrolilodon (NMP). 24.90 g of KF-8010) (amino equivalent 415) (DAPS) manufactured by Kogyo Co., Ltd. was added dropwise and reacted at 180 ° C. for 2 hours. Next, 20.04 g of 5,5′-methylenebis [2-aminobenzoic acid] (MBA) was added and reacted at 180 ° C. for 2 hours. Next, the temperature was lowered to 100 ° C., and 8.10 g of glycidyl methacrylate was added dropwise and reacted for 0.5 hour to obtain a photosensitive polyimide solution.

(Preparation of photosensitive polyimide ink)
2 parts by weight of photopolymerization initiator 2,4-diethylthioxanthone, 4 parts by weight of isoamyl p-dimethylaminobenzoate, 15 parts by weight of trimethylolpropane triacrylate, biphenol type, based on 100 parts of solid content in the photosensitive polyimide solution 6 parts by weight of epoxy resin YX4000HK, 5 parts by weight of barium sulfate, and 3 parts by weight of an antifoaming agent were added and kneaded with three rolls to prepare a photosensitive polyimide ink composition.

This photosensitive polyimide ink composition was printed on a copper-clad laminate with a 200-mesh screen plate, left in a hot air circulation type constant temperature dryer maintained at 80 ° C. for 30 minutes, and then various patterns were formed on the coating film having a thickness of 15 μm. A negative test pattern film having a diameter was brought into close contact with a vacuum, and irradiated with ultraviolet rays having a wavelength of 365 nm at 600 mJ / cm ² using an exposure machine with a built-in ORC HMW 680C metal halide lamp. After that, spray 1kgf / cm ² with a 1% sodium carbonate aqueous solution heated to 30 ° C for 1 minute from a distance of 15cm, then spray rinse with warm water at 30 ° C, and then dry to expose the exposed and unexposed areas. When the portion was observed, a well-cut 50 μm circular opening and a 30 μm line & space pattern were observed. The film cured by this exposure had good characteristics similar to Example 8.

  This photosensitive polyimide ink composition was printed on a copper-clad laminate with a 200-mesh screen plate, prebaked at 80 ° C. for 30 minutes, and then further baked at 150 ° C. for 60 minutes to perform a plating test.

  When working according to the usage method of ICP Nicolon (Okuno Pharmaceutical Co., Ltd., electroless nickel plating process), the nickel coating was cut without damaging the coating film. Furthermore, favorable gold plating was performed even in the operation using OPC Muden Gold (Okuno Pharmaceutical Co., Ltd., electroless gold plating process).

  Moreover, after printing this photosensitive polyimide ink on an FPC pattern, prebaking at 80 ° C. for 30 minutes, and further baking at 150 ° C. for 60 minutes, the method described in 8.6 of JIS C 5016 is used. A bending test of 180 degrees with a bending radius of R2.5 was performed. No disconnection was observed even after repeated bending 10 times.

  Furthermore, this photosensitive polyimide ink was printed on a copper-clad laminate with a 200-mesh screen plate, prebaked at 80 ° C. for 30 minutes, and then further baked at 150 ° C. for 60 minutes to perform a plating adhesion test. It was. A grid of 1 mm square was put on the surface of the coating film with a cutter knife, and the cellophane tape was brought into close contact with each other. When the film was peeled off quickly and peeled off, no peeling was observed.

  Also, this photosensitive polyimide ink is printed on a copper clad laminate, pre-baked at 80 ° C. for 30 minutes, and further baked at 150 ° C. for 60 minutes to contact the solder melt surface maintained at 260 ° C. It was allowed to float for 30 seconds and repeated 6 times, but there was no change in the appearance of the coating film.

Claims (10)

(a) an acid dianhydride component mainly composed of an alicyclic tetracarboxylic dianhydride represented by the following general formula (1):

(In general formula (1), R is a carboxylic dianhydride residue of alicyclic tetracarboxylic dianhydride (excluding a carboxylic dianhydride residue of cyclohexane tetracarboxylic dianhydride). is there.)
A diamine component having as a main component an aromatic diamine having two carboxyl groups represented by the following general formula (2) in the molecule at a ratio of 70 mol% or more with respect to the total diamine component, or the following general formula (2) To the polyimide synthesized by reaction with the aromatic diamine shown,
(b) When the acid dianhydride component is the alicyclic tetracarboxylic dianhydride represented by the general formula (1), the alicyclic tetracarboxylic dianhydride and the following general formula (2) To the polyimide synthesized by the reaction with a diamine component mainly composed of an aromatic diamine having two carboxyl groups in the molecule,
(c) When the acid dianhydride component mainly composed of cyclohexanetetracarboxylic dianhydride and the diamine component are aromatic diamines having two carboxyl groups in the molecule represented by the following general formula (2) To polyimide synthesized by reaction with diamine component, or
(d) an acid dianhydride component composed mainly of cyclohexanetetracarboxylic dianhydride, an aromatic diamine having two carboxyl groups in the molecule represented by the general formula (2), and diaminopolysiloxane ( A polyimide synthesized by reaction with a diamine component containing at least one aromatic diamine among DAPS), bis-4-aminophenoxyphenylpropane (BAPP), and 3,5-diaminobenzoic acid (DABA);
A photosensitive polyimide obtained by subjecting a compound having a (meth) acryloyl group to an addition reaction or condensation reaction with a part of a carboxyl group present in the polyimide and being soluble in an organic solvent.

(In the general formula (2), X represents O, CH ₂ , C (CF ₃ ) ₂ , O—C ₆ H ₄ —C (CH ₃ ) ₂ —C ₆ H ₄ —O, or a direct bond. .)   When the acid dianhydride component contains an alicyclic tetracarboxylic dianhydride represented by the general formula (1) as the main component, the acid dianhydride component is an aromatic tetracarboxylic dianhydride. The photosensitive polyimide according to claim 1, comprising:   The photosensitive polyimide according to claim 2, wherein the content of the aromatic tetracarboxylic dianhydride is less than 35 mol% with respect to the acid dianhydride component.   The said diamine component contains aromatic diamine other than the aromatic diamine shown by the said General formula (2), The photosensitive polyimide of any one of the said Claims 1-3 characterized by the above-mentioned.   The photosensitive polyimide according to claim 1, wherein the diamine component contains diaminopolysiloxane.   The photosensitive polyimide according to claim 5, wherein the content of the diaminopolysiloxane is 40 mol% or less with respect to the diamine component.   A photosensitive polyimide ink composition comprising the photosensitive polyimide according to any one of claims 1 to 6 and an organic solvent capable of dissolving the photosensitive polyimide.   The photosensitive polyimide ink composition according to claim 7, comprising a photopolymerization initiator, a sensitizer, a heat-resistant epoxy resin, and an inorganic filler.   5 to 70 parts by weight of the (meth) acrylate compound, 1 to 50 parts by weight of a photopolymerization initiator and sensitizer, 10 to 70 parts by weight of a heat-resistant epoxy resin, and 10 inorganic fillers with respect to 100 parts by weight of the photosensitive polyimide. The photosensitive polyimide ink composition according to claim 8, comprising ˜80 parts by weight.   An insulating film obtained by applying the photosensitive polyimide ink composition according to any one of claims 7 to 9 to a substrate, pre-baking, exposing, developing, and post-baking.