JP2006119513A - Photosensitive resin composition and photosensitive dry film resist, and printed wiring board using same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an excellent photosensitive resin composition and photosensitive dry film resist capable of undergoing water-based development, ensuring a good pattern shape and providing a film having excellent moisture and heat resistances after curing, and to provide usage of these. <P>SOLUTION: The photosensitive resin composition contains (A) a soluble polyimide having a carboxyl group and/or a hydroxyl group and (B) a (meth)acrylic compound, wherein the soluble polyimide (A) is a soluble polyimide prepared using diphenylsulfone-3,4,3',4'-tetracarboxylic acid dianhydride as a part of raw materials. The photosensitive dry film resist is produced from the photosensitive resin composition. A printed wiring board using the photosensitive dry film resist as an insulating protective layer is also provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a photosensitive resin composition, a photosensitive dry film resist, and a printed wiring board used for mounting electronic parts such as precision electronic equipment materials used in portable electronic equipment such as digital home appliances and laptop computers. .

  In recent years, electronic devices used in these electronic devices are required to be further reduced in size and weight as the electronic devices become more functional, smaller and lighter. For this reason, it is required to increase the functionality and performance of electronic components by performing high-density mounting of semiconductor elements, etc. on printed wiring boards, miniaturization of wiring, and multilayering of printed wiring boards. ing. Further, in order to cope with the miniaturization of the wiring, an insulating material having higher electrical insulation is required to protect the wiring.

  By the way, when producing the printed wiring board, a photosensitive material is used in various applications. That is, formation of a patterned circuit (pattern circuit) on a printed wiring board substrate, formation of a protective layer for protecting the printed wiring board surface and pattern circuit, formation of an interlayer insulating layer of a multilayer printed wiring board, etc. In addition, a photosensitive material is used. As photosensitive materials used for such applications, there are liquid photosensitive materials and film-shaped photosensitive materials. Among these, the film-like photosensitive material has advantages such as excellent film thickness uniformity and workability compared to the liquid photosensitive material. Therefore, a resist film for a pattern circuit used for forming a pattern circuit, a photosensitive cover lay film used for forming the protective layer, a photosensitive dry film resist used for forming the interlayer insulating layer, etc. A film-like photosensitive material is also used.

  As the above-mentioned photosensitive coverlay film and photosensitive dry film resist (hereinafter, both are collectively referred to as photosensitive dry film resist), only acrylic films and epoxy films are currently on the market. There is a problem that it is inferior in heat resistance, chemical resistance and bending resistance.

A material using a polyimide precursor excellent in heat resistance, chemical resistance and flexibility (Patent Document 1) is also known. Such a polyimide precursor is an adhesive for electronic materials as a liquid photosensitive material. It was used as an insulating material and not as a photosensitive dry film resist.
In recent years, a dry film resist containing polyimide (Patent Document 2) has also been reported. However, depending on the structure of the tetracarboxylic dianhydride and diamine used as a raw material for polyimide, there may still be room for improvement in terms of moisture resistance and aqueous developability.
JP 2002-167367 A JP 2003-167336 A

  INDUSTRIAL APPLICABILITY The present invention is capable of water-based development, a good pattern shape is obtained, and the cured film has excellent moisture resistance and heat resistance, a photosensitive resin composition and a photosensitive dry film resist, and these Is to provide usage.

The first of the present invention is
(A) A photosensitive resin composition comprising a soluble polyimide having a carboxyl group and / or a hydroxyl group, and (B) a (meth) acrylic compound, wherein the soluble polyimide as the component (A) is A photosensitive resin composition characterized by being a soluble polyimide using diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride as a part of a raw material,
It is.

  By this structure, the dry film resist after curing has excellent moisture resistance and heat resistance.

The second of the present invention is
The soluble polyimide as the component (A) has at least one carbon-carbon double bond selected from the group consisting of an acryl group, a methacryl group, a vinyl group, and an allyl group. 1. The photosensitive resin composition according to 1,
It is.

  With this configuration, the curability of the exposed portion of the resin composition and / or dry film resist can be improved.

The third aspect of the present invention is
The photosensitive resin composition according to the first or second aspect of the present invention, wherein the soluble polyimide as the component (A) has a weight average molecular weight of 10,000 or less per carboxyl group and / or hydroxyl group. object,
It is.

  With this configuration, aqueous development is possible.

The fourth aspect of the present invention is
A photosensitive dry film resist produced using the photosensitive resin composition according to any one of the first to third aspects of the present invention;
It is.

The fifth aspect of the present invention is
When a 1% by weight sodium hydroxide aqueous solution is used as an aqueous developer at 40 ° C. and a spray developing machine is used as a developing means, the dissolution time under a spray pressure of 0.85 MPa is 180 seconds or less. The photosensitive dry film resist according to the fourth aspect of the present invention,
It is.

  By virtue of this configuration, the developer is water-based, so the burden on the environment is reduced.

The sixth of the present invention is
A printed wiring board, wherein the photosensitive dry film resist according to the fourth or fifth aspect of the present invention is used as an insulating protective layer,
It is.

  With this configuration, aqueous development is possible, a good pattern shape is obtained, and a printed wiring board having excellent moisture resistance and heat resistance can be provided.

The photosensitive resin composition according to the present invention and the photosensitive dry film resist produced therefrom have good aqueous developability (developability with a basic aqueous solution) and are excellent in moisture resistance, heat resistance, etc. It has become.
Therefore, the present invention can be suitably used not only in the industry for manufacturing printed wiring boards such as FPC, for example, in the resin industry for manufacturing resin materials for electronic components, but also in electronic devices using such printed wiring boards. There is an effect that it can be suitably used in the industrial field.

  The photosensitive resin composition according to the present invention includes (A) a soluble polyimide having a carboxyl group and / or a hydroxyl group, and (B) a photosensitive resin composition containing a (meth) acrylic compound. In the photosensitive resin composition, the soluble polyimide as the component (A) is a soluble polyimide using diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride as a part of the raw material. Although it contains the photosensitive resin composition characterized by being, (C) Other components may be contained as needed. For example, the resulting photosensitive dry film resist can contain components that impart various physical properties such as adhesion, flame retardancy, heat resistance, and bending resistance. In addition, the photosensitive dry film resist which concerns on this invention is produced from the photosensitive resin composition which concerns on this invention. Hereinafter, each component will be described in detail.

<(A) Soluble polyimide having carboxyl group and / or hydroxyl group>
In the photosensitive resin composition according to the present invention, by using a soluble polyimide having a carboxyl group and / or a hydroxyl group, the resulting photosensitive dry film resist has heat resistance, flex resistance, excellent mechanical properties, and electrical insulation. , Chemical resistance can be imparted. Furthermore, since it contains a carboxyl group and / or a hydroxyl group (preferably a phenolic hydroxyl group), aqueous development is possible.

  The soluble polyimide of the present invention is characterized by using diphenylsulfone-3,4,3 ', 4'-tetracarboxylic dianhydride as a part of the raw material. Diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride is not only excellent in moisture resistance because there is no hydrolyzable group such as an ester bond, but also has solubility in organic solvents, aqueous development The property is also good.

  Furthermore, the soluble polyimide having a carboxyl group and / or a hydroxyl group as the component (A) has at least one carbon-carbon double bond selected from the group consisting of an acryl group, a methacryl group, a vinyl group, and an allyl group. For example, it is preferable to have in the side chain. By having a photosensitive group such as an acrylic group, a methacryl group, a vinyl group, or an allyl group in the soluble polyimide molecule, the curability of the exposed portion can be improved.

  The soluble polyimide is not particularly limited as long as it is a polyimide that dissolves in an organic solvent, but in the present invention, a soluble polyimide having a solubility of 1.0 g or more at 20 ° C. with respect to 100 g of the organic solvent. preferable. More preferably, it exhibits a solubility of 5.0 g or more at 20 ° C., and more preferably a solubility of 10 g or more at 20 ° C. If the solubility at 20 ° C. in 100 g of an organic solvent is less than 1.0 g, it tends to be difficult to form a photosensitive dry film resist at a desired thickness. The organic solvent is not particularly limited, but includes formamide solvents such as N, N-dimethylformamide and N, N-diethylformamide, ether solvents such as 1,4-dioxane, 1,3-dioxolane, and tetrahydrofuran. Can be mentioned.

  The weight average molecular weight of the soluble polyimide having a carboxyl group and / or a hydroxyl group is not particularly limited, but is preferably 5,000 to 200,000, and more preferably 10,000 to 100,000. If the weight average molecular weight is less than 5,000, the photosensitive dry film resist produced using the photosensitive resin composition of the present invention tends to be sticky, and the cured film tends to have poor flex resistance. . On the other hand, if the weight average molecular weight is greater than 200,000, the solution viscosity of the soluble polyimide having a carboxyl group and / or a hydroxyl group tends to be too high and the handling tends to be difficult, and the developability of the produced photosensitive dry film resist is lowered. There is a case. The weight average molecular weight can be measured by size exclusion chromatography (SEC), for example, HLC8220GPC manufactured by Tosoh Corporation.

  The weight average molecular weight (hereinafter also referred to as acid equivalent) per carboxyl group and / or hydroxyl group in the soluble polyimide having a carboxyl group and / or hydroxyl group is preferably 10,000 or less, and preferably 5,000 or less. More preferred is 3000 or less. If the acid equivalent exceeds 10,000, aqueous development of the photosensitive dry film resist produced using the photosensitive resin composition of the present invention tends to be difficult. In addition, the acid equivalent of the said soluble polyimide can be calculated | required by calculating from the chemical composition of the soluble polyimide which has a carboxyl group and / or a hydroxyl group.

  The details of the calculation are as follows.

  The “weight average molecular weight per carboxyl group and / or hydroxyl group” in a soluble polyimide having only carboxyl groups is the weight average molecular weight per carboxyl group.

  The “weight average molecular weight per carboxyl group and / or hydroxyl group” in the soluble polyimide having only hydroxyl groups is the weight average molecular weight per hydroxyl group.

  The “weight average molecular weight per carboxyl group and / or hydroxyl group” in the soluble polyimide having a carboxyl group and a hydroxyl group means that when the repeating unit of the soluble polyimide has A carboxyl groups and B hydroxyl groups, It is a weight average molecular weight obtained by dividing the weight average molecular weight by (A + B).

<Production method of polyimide>
Hereinafter, in order to explain the method for producing a soluble polyimide having a carboxyl group and / or a hydroxyl group, a method for synthesizing a polyamic acid, a method for dehydrating and ring-closing polyamic acid to imidize, and further, the obtained carboxyl group and / or Alternatively, a method for modifying a soluble polyimide having a hydroxyl group and introducing a photosensitive group such as an acryl group, a methacryl group, a vinyl group, or an allyl group into the polyimide will be described in detail.

<Synthesis of polyamic acid>
The soluble polyimide having a carboxyl group and / or a hydroxyl group can be obtained from a polyamic acid that is a precursor thereof. This polyamic acid can be obtained by reacting diamine and acid dianhydride in an organic solvent. Specifically, in an inert atmosphere such as argon or nitrogen, the diamine is dissolved in an organic solvent or dispersed in a slurry to obtain a diamine solution. On the other hand, the acid dianhydride may be added to the diamine solution after being dissolved or dispersed in an organic solvent or in a solid state.

  Although it does not specifically limit as diamine used in order to synthesize | combine the polyamic acid which is the precursor of the soluble polyimide which has a carboxyl group and / or a hydroxyl group of this invention, From the point of aqueous | water-based developability, it is in 1 molecule. It is preferable to use a diamine having one or more carboxyl groups and / or hydroxyl groups as at least a part of the raw material. In view of heat resistance and chemical resistance, it is preferable to use an aromatic diamine having one or more aromatic rings in one molecule as at least a part of the raw material. In particular, if an aromatic diamine having one or more carboxyl groups and / or hydroxyl groups in one molecule is used as a part of the raw material, heat resistance and aqueous developability can be imparted to the resulting photosensitive dry film resist. This is particularly preferable because it can be performed.

  Although it does not specifically limit as aromatic diamine which has a carboxyl group and / or a hydroxyl group, The following general formula (1):

（式中、Ｒ¹はカルボキシル基若しくは水酸基、Ｒ²及びＲ³は、各々同一であっても異なっていてもよいが、水素原子、炭素数１〜９のアルキル基、炭素数２〜１０のアルコキシ基、又は−ＣＯＯＲ⁴（Ｒ⁴は炭素数１〜９のアルキル基を示す。）であり、Ｘは、−Ｏ−、−Ｓ−、−ＳＯ₂−、−Ｃ（ＣＨ₃）₂−、−ＣＨ₂−、−Ｃ（ＣＨ₃）（Ｃ₂Ｈ₅）−、又は−Ｃ（ＣＦ₃）₂−である。ｍ及びｎは、各々ｍ＋ｎ＝４を満たす０以上の整数であり、ｐ及びｑは、各々ｐ＋ｑ＝４を満たす０以上の整数である。ｒは０〜１０の整数である。）で表される芳香族系ジアミンを可溶性ポリイミドの原料の一部として用いることが好ましい。

(In the formula, R ¹ is a carboxyl group or a hydroxyl group, and R ² and R ³ may be the same or different. However, a hydrogen atom, an alkyl group having 1 to 9 carbon atoms, An alkoxy group or —COOR ⁴ (R ⁴ represents an alkyl group having 1 to 9 carbon atoms), and X is —O—, —S—, —SO ₂ —, —C (CH ₃ ) ₂ —. , —CH ₂ —, —C (CH ₃ ) (C ₂ H ₅ ) —, or —C (CF ₃ ) ₂ —, m and n are each an integer of 0 or more satisfying m + n = 4, p and q are each an integer of 0 or more satisfying p + q = 4, and r is an integer of 0 to 10.) It is preferable to use an aromatic diamine represented by a part of the raw material of the soluble polyimide. .

  The aromatic diamine having a carboxyl group is not particularly limited, and examples thereof include diaminobenzoic acid such as 3,5-diaminobenzoic acid and 3,3′-diamino-4,4′-dicarboxybiphenyl. Carboxybiphenyl compounds such as 4,4′-diamino-2,2 ′, 5,5′-tetracarboxybiphenyl, 4,4′-diamino-3,3′-dicarboxydiphenylmethane, 3,3′-diamino Carboxydiphenylalkanes such as 4,4′-dicarboxydiphenylmethane, carboxydiphenyl ether compounds such as 4,4′-diamino-2,2 ′, 5,5′-tetracarboxydiphenyl ether, 3,3′-diamino-4 , 4′-dicarboxydiphenyl sulfone, diphenyl sulfone compounds, 2,2-bis [4- (4 Bis (carboxyphenoxy) biphenyl compounds such as amino-3-carboxyphenoxy) phenyl] propane, bis [(carboxyphenoxy) phenyl such as 2,2-bis [4- (4-amino-3-carboxyphenoxy) phenyl] sulfone ] A sulfone compound etc. can be illustrated.

  Among them, some of the structural formulas of particularly preferred carboxyl group-containing aromatic diamines are shown below (Formula (2), Formula (3), Formula (4), Formula (5)).

次に、水酸基を有する芳香族系ジアミンとしては、特に限定されるものではないが、例えば、２，２’−ジアミノビスフェノールＡ、２，２’−ビス（３−アミノ−４−ヒドロキシフェニル）ヘキサフルオロプロパン、ビス（２−ヒドロキシ−３−アミノ−５−メチルフェニル）メタン、２，６−ジ［（２−ヒドロキシ−３−アミノ−５−メチルフェニル）メチル］−４−メチルフェノール、２，６−ジ［（２−ヒドロキシ−３−アミノ−５−メチルフェニル）メチル］−４−ヒドロキシ安息香酸プロピル等の化合物を挙げることができる。

Next, the aromatic diamine having a hydroxyl group is not particularly limited. For example, 2,2′-diaminobisphenol A, 2,2′-bis (3-amino-4-hydroxyphenyl) hexa Fluoropropane, bis (2-hydroxy-3-amino-5-methylphenyl) methane, 2,6-di [(2-hydroxy-3-amino-5-methylphenyl) methyl] -4-methylphenol, 2, Mention may be made of compounds such as 6-di [(2-hydroxy-3-amino-5-methylphenyl) methyl] -4-hydroxybenzoate propyl.

  Among them, some of the structural formulas of particularly preferred hydroxyl group-containing aromatic diamines are shown below (formula (6), formula (7), formula (8), formula (9), formula (10), formula (11)). (12)).

これらのジアミンを原料の一部として使用することで、得られるカルボキシル基及び／又は水酸基を含有する可溶性ポリイミドの酸当量が低くなり、水系現像性を向上させることができる。

By using these diamines as part of the raw material, the acid equivalent of the resulting soluble polyimide containing a carboxyl group and / or a hydroxyl group is lowered, and the aqueous developability can be improved.

  Needless to say, in addition to the diamine having a carboxyl group and / or a hydroxyl group, other known diamines may be used simultaneously as part of the raw material of the soluble polyimide. For example, bis [4- (3-aminophenoxy) phenyl] sulfone, reactive silicone containing amino groups at both ends of the siloxane structure (hereinafter referred to as silicon diamine or silicone diamine), [bis (4-amino-3 -Carboxy) phenyl] methane and the like. In particular, it is preferable to use silicon diamine from the viewpoint that the elastic modulus of the film can be lowered. The said diamine can be used individually or in combination of 2 or more types.

  On the other hand, as the acid dianhydride used for synthesizing the polyamic acid, it is particularly preferable to use at least diphenylsulfone-3,4,3 ', 4'-tetracarboxylic dianhydride. As long as diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride is used, other acid dianhydrides may be used in combination, but are not particularly limited. From the viewpoint of improving heat resistance It is preferable to use an acid dianhydride having 1 to 4 aromatic rings or an alicyclic acid dianhydride. In order to obtain a polyimide resin having high solubility in an organic solvent, it is preferable to use at least a part of an acid dianhydride having two or more aromatic rings, and an acid dianhydride having four or more aromatic rings. More preferably, it is used as at least a part.

  Examples of the acid dianhydride include aliphatic or alicyclic tetracarboxylic dianhydrides such as butanetetracarboxylic dianhydride and 1,2,3,4-cyclobutanetetracarboxylic dianhydride, Mellitic dianhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 2,2′-bis (hydroxyphenyl) propanedibenzoate-3,3 ′, 4,4′- Tetracarboxylic dianhydride, 2,3 ′, 3,4′-biphenyl ether tetracarboxylic dianhydride, 3,4,3 ′, 4′-biphenyl ether tetracarboxylic dianhydride, biphenyl-3,4 Aromatic tetracarboxylic dianhydrides such as 1,3 ', 4'-tetracarboxylic dianhydride, 1,3,3a, 4,5,9b-hexahydro-2,5-dioxo-3-furanyl-naphtho 1,2- And aliphatic tetracarboxylic dianhydride having an aromatic ring such as] furan-1,3-dione.

  When synthesizing polyamic acid using the diamine and acid dianhydride, the reaction may be performed using at least one of each of the diamine and acid dianhydride. That is, for example, by performing a polymerization reaction in an organic solvent using a diamine component containing at least a diamine containing a carboxyl group and / or a hydroxyl group and the acid dianhydride as described above, A polyamic acid containing at least one carboxyl group and / or hydroxyl group in the molecular chain can be obtained.

  At this time, if 1 type of diamine and 1 type of acid dianhydride are substantially equimolar, it will become a polyamic acid of 1 type of acid dianhydride components and 1 type of diamine components. Further, when two or more kinds of acid dianhydride components and two or more kinds of diamine components are used, the molar ratio of the total amount of plural diamine components and the molar ratio of the total amount of plural acid dianhydride components are substantially equimolar. If adjusted, a polyamic acid copolymer can be optionally obtained.

  The temperature condition of the reaction between the diamine and the acid dianhydride (polyamide acid synthesis reaction) is not particularly limited, but is preferably 80 ° C. or less, more preferably 0 to 50 ° C. If it exceeds 80 ° C., the polyamic acid may be decomposed. Conversely, if it is 0 ° C. or less, the progress of the polymerization reaction may be slow. Moreover, what is necessary is just to set reaction time arbitrarily in the range of 10 minutes-30 hours.

  Furthermore, the organic solvent used for the synthesis reaction of the polyamic acid is not particularly limited as long as it is an organic polar solvent. However, as the reaction between the diamine and the acid dianhydride proceeds, polyamic acid is generated, and the viscosity of the reaction solution increases. Moreover, as will be described later, the polyamic acid solution obtained by synthesizing the polyamic acid can be heated under reduced pressure to simultaneously remove the organic solvent and imidize. Therefore, as the organic solvent, it is advantageous in terms of the process to select an organic solvent that can dissolve the polyamic acid and has a low boiling point as much as possible.

  Specifically, examples of the organic solvent used in the polyamic acid synthesis reaction include a formamide solvent such as N, N-dimethylformamide, an acetamide solvent such as N, N-dimethylacetamide, N-methyl-2-pyrrolidone, and the like. Examples thereof include pyrrolidone solvents such as N-vinyl-2-pyrrolidone and ether solvents such as tetrahydrofuran, dioxane and dioxolane.

<Imidization of polyamic acid>
Next, a method for imidizing the polyamic acid to obtain a polyimide using the polyamic acid will be described. Imidization is performed by dehydrating and ring-closing the polyamic acid. This dehydration ring closure can be performed by an azeotropic method using an azeotropic solvent, a thermal method, or a chemical method.

  In the azeotropic method using an azeotropic solvent, a solvent that azeotropes with water such as toluene and xylene is added to the polyamic acid solution, and the temperature is raised to 170 to 200 ° C. to actively generate water generated by dehydration ring closure. The reaction may be carried out for about 1 to 5 hours while removing from the system. After completion of the reaction, it is precipitated in an alcohol solvent such as methanol, washed with an alcohol solvent as necessary, and then dried to obtain a polyimide resin.

  Dehydration ring closure by a thermal method may be performed by heating the polyamic acid solution. Alternatively, the polyamic acid solution may be cast or applied to a film-like support such as a glass plate, a metal plate, or PET (polyethylene terephthalate), and then heat treatment may be performed within a range of 80 ° C to 300 ° C. Furthermore, the polyamic acid solution can be directly dehydrated and ring-closed by placing the polyamic acid solution directly into a container that has been subjected to a release treatment such as coating with a fluororesin, and then drying by heating under reduced pressure. Polyimide can be obtained by dehydration and ring closure of polyamic acid by such a thermal method.

  In addition, although the heating time of each said process changes with the process amount and heating temperature of the polyamic acid solution which performs dehydration ring closure, generally it is performed in the range of 1 minute-5 hours after the processing temperature reaches the maximum temperature. It is preferable.

  On the other hand, dehydration and ring closure by a chemical method may be performed by adding a dehydrating agent and, if necessary, a catalytic amount of a tertiary amine as a catalyst to the polyamic acid solution and performing a heat treatment. Note that this heat treatment refers to the heat treatment performed by the thermal method described above. Thereby, a polyimide can be obtained.

  As the dehydrating agent in the chemical method, acid anhydrides such as acetic anhydride and propionic anhydride are generally used. As the tertiary amine, pyridine, isoquinoline, triethylamine, trimethylamine, imidazole, picoline, or the like may be used.

  In addition, when the soluble polyimide of the present invention has a hydroxyl group, the reaction between the acid anhydride added as a dehydrating agent and the hydroxyl group is considered, so the acid anhydride to be used is stoichiometrically necessary for imidization. A minimum amount is preferred.

<Polyimide having at least one carbon-carbon double bond selected from the group consisting of an acryl group, a methacryl group, a vinyl group, and an allyl group>
Furthermore, the soluble polyimide having a carboxyl group and / or a hydroxyl group according to the present invention is a molecule in order to cause a polyimide and epoxy (meth) acrylate to undergo a crosslinking reaction or to cause a polyimide molecule to undergo a crosslinking reaction in an exposure treatment described later. Among these, it is more preferable that the side chain has at least one carbon-carbon double bond selected from the group consisting of an acryl group, a methacryl group, a vinyl group, and an allyl group. In addition, the said soluble polyimide may have the functional group which has a carbon-carbon double bond other than the functional group mentioned above.

  For example, the polyimide having any carbon double bond among the acrylic group, methacryl group, vinyl group, and allyl group in the side chain is the above-described carbon-carbon double bond to the above-described polyimide having a carboxyl group and / or a hydroxyl group. It can be obtained by reacting and modifying a compound having the following. The compound having a carbon-carbon double bond is not particularly limited as long as it reacts with a carboxyl group and / or a hydroxyl group in the polyimide molecular chain. However, an epoxy compound having a carbon-carbon double bond, (meth) acrylic anhydride And allyl halides such as allyl bromide.

  When the epoxy compound having a carbon-carbon double bond is reacted, in an inert solvent, in the presence of an organic base such as pyridine or triethylamine, a polyimide having a carboxyl group and / or a hydroxyl group, and an epoxy having a carbon-carbon double bond It is exemplified that the compound is reacted, and the target soluble polyimide having a carbon-carbon double bond can be obtained.

  The reaction temperature is preferably 40 ° C. or more and 130 ° C. or less at which the epoxy group reacts with the carboxyl group and / or the hydroxyl group. In particular, it is desirable to carry out the reaction at a temperature at which the carbon-carbon double bond does not cause a reaction such as polymerization due to heat. Specifically, it is more preferably 40 ° C. or higher and 100 ° C. or lower, further preferably 50 ° C. or higher and 80 ° C. or lower. The reaction time can be appropriately selected, but is generally about 1 hour to 20 hours.

  The reaction solution obtained by the above reaction may be used in a solution state after completion of the reaction depending on the purpose, or precipitated in an alcohol solvent such as methanol, and washed with an alcohol solvent as necessary. You may go.

  The epoxy compound having a carbon-carbon double bond is not particularly limited as long as it has an epoxy group and the carbon-carbon double bond in the same molecule. For example, glycidyl acrylate, glycidyl methacrylate, allyl glycidyl ether, Specific examples include glycidyl vinyl ether. Among these, glycidyl methacrylate is particularly preferable because it is inexpensive and easily available and has good reactivity.

  In the case of reacting (meth) acrylic anhydride, in an inert solvent, in the presence of an organic base such as pyridine or triethylamine, the hydroxyl group in the polyimide molecular chain is condensed with (meth) acrylic anhydride, The soluble polyimide which has the target carbon-carbon double bond can be obtained.

  The reaction temperature is preferably 0 ° C. or higher and 100 ° C. or lower that allows acylation of the hydroxyl group in the polyimide molecular chain. In particular, it is desirable to react at a temperature at which the carbon-carbon double bond does not cause a reaction such as polymerization due to heat. Specifically, it is more preferably 10 ° C. or higher and 100 ° C. or lower, and further preferably 20 ° C. or higher and 80 ° C. or lower. The reaction time can be appropriately selected, but is generally about 1 hour to 20 hours.

  In order to remove (meth) acrylic acid generated by the reaction, the reaction solution obtained by the above reaction is preferably precipitated in an alcohol solvent such as methanol and washed with an alcohol solvent as necessary.

  In the case of reacting an allyl halide, it is exemplified to react a polyimide containing a hydroxyl group with an allyl halide in the presence of an organic base such as pyridine or triethylamine in an inert solvent. Can be obtained.

  The reaction temperature is preferably 0 ° C. or higher and 100 ° C. or lower at which reaction is possible. In particular, it is desirable to carry out the reaction at a temperature at which the carbon-carbon double bond does not cause a reaction such as polymerization due to heat. Specifically, it is more preferably 0 ° C. or higher and 80 ° C. or lower, and further preferably 20 ° C. or higher and 50 ° C. or lower. The reaction time can be appropriately selected, but is generally about 1 hour to 20 hours.

  The reaction solution obtained by the above reaction is preferably precipitated in an alcohol solvent such as methanol, and washed with an alcohol solvent as necessary.

  In any of the above reactions, in order to maintain water-based developability after introducing the target carbon-carbon double bond, not all carboxyl groups and / or hydroxyl groups in the polyimide molecular chain are reacted. It is preferable to adjust the number of equivalents of the compound having a carbon-carbon double bond to be reacted so that a hydroxyl group remains. Specifically, the acid equivalent of the soluble polyimide having a carboxyl group and / or a hydroxyl group after the reaction may be adjusted to 10,000 or less.

  Moreover, in order to prevent that a carbon-carbon double bond reacts during reaction, it is preferable to add a polymerization inhibitor. Examples of the polymerization inhibitor include hydroquinone derivatives such as p-methoxyphenol, phenothiazine, and N-nitrohydroxylamine salts.

  The thus obtained polyimide into which a photopolymerizable group and / or heat-polymerizable functional group called a carbon-carbon double bond has been introduced has good curability and adhesiveness.

<(B) (Meth) acrylic compound>
Next, the (meth) acrylic compound as the component (B) will be described. By containing the component (B) in the photosensitive resin composition, not only good curability is imparted, but also the viscoelasticity at the time of thermal processing of the photosensitive dry film resist to be produced is lowered, and at the time of thermal lamination Fluidity can be imparted. That is, heat lamination at a relatively low temperature is possible, and circuit irregularities can be embedded.

  In the present invention, the (meth) acrylic compound is a compound selected from the group consisting of (meth) acrylic compounds, epoxy (meth) acrylates, polyester (meth) acrylates, urethane (meth) acrylates, and imide (meth) acrylates. Show. In the present invention, the (meth) acrylic compound refers to an acrylic compound and / or a methacrylic compound.

  The said (meth) acrylic-type compound may use only 1 type, and may combine 2 or more types. The total weight of the (meth) acrylic compound contained in the photosensitive resin composition in the present invention is 1 to 100 parts by weight with respect to 100 parts by weight of the soluble polyimide as the component (A). Preferably, it is used in the range of 1 to 80 parts by weight, more preferably in the range of 1 to 50 parts by weight.

  When (meth) acrylic compound that exceeds 100 parts by weight as component (B) is used with respect to 100 parts by weight of soluble polyimide as component (A), the heat resistance of the resulting photosensitive dry film resist decreases. End up.

  The photosensitive resin composition of the present invention contains a (meth) acrylic compound containing at least one or more epoxy groups and one or more (meth) acrylic groups in one molecule as the component (B). Is preferred. By using such a (meth) acrylic compound, it becomes possible to improve the hydrolysis resistance of the resulting photosensitive dry film resist and the adhesion to copper foil.

  Although it does not specifically limit as a (meth) acrylic-type compound which contains at least 1 or more epoxy group and 1 or more (meth) acryl group in 1 molecule, For example, glycidyl compounds, such as glycidyl methacrylate, NK oligo EA-1010 , EA-6310 (manufactured by Shin-Nakamura Chemical Co., Ltd.) and the like.

  Moreover, it is preferable to contain the epoxy (meth) acrylate which contains at least 2 or more hydroxyl group in 1 molecule as (B) component in the photosensitive resin composition of this invention. By using such an epoxy (meth) acrylate, the solubility of the resulting photosensitive dry film resist in an aqueous developer is improved, and the development time can be shortened.

  Although it does not specifically limit as an epoxy (meth) acrylate which contains at least 2 or more hydroxyl group in 1 molecule, Lipoxy SP-2600 (made by Showa Polymer), NK oligo EA-1020, NK oligo EA-6340 (Shin Nakamura) Chemical), Karayad R-280, Karayad R-190 (Nippon Kayaku), Ebecryl 600, Ebecryl 3700 (Daicel UCB) and other bisphenol A type epoxy acrylates, KRM7856, Ebecryl 3604, Ebecryl 3702, Ebecryl 3703, Ebecryl 3703, Ebecryl 3703, Ebecryl 3703 ), Modified bisphenol A type epoxy acrylate such as LR9019 (BASF), aliphatic epoxy acrylate such as LR8765 (BASF), NK oligo EA Modifications such as phenol novolac epoxy acrylate such as 6320, NK oligo EA-6340 (manufactured by Shin-Nakamura Chemical), Karayad R-167, MAX-2104 (manufactured by Nippon Kayaku), Denacol acrylate DA-212 (manufactured by Nagase Kasei) , 6-hexanediol diacrylate, modified phthalic acid diacrylate such as Denacol acrylate DA-721 (manufactured by Nagase Kasei), cresol novolac epoxy acrylate such as NK oligo EA-1020 (manufactured by Shin-Nakamura Chemical), etc. it can. In particular, KRM7856, Ebecryl 3703, and Ebecryl 3708 are preferable in terms of flexibility, heat resistance, and adhesion.

  By using polyester (meth) acrylate, flexibility can be imparted to the produced photosensitive dry film resist. Although it does not specifically limit as polyester (meth) acrylate, For example, Aronix M-5300, M-6100, M-7100 (made by Toagosei) etc. can be mentioned.

  By using urethane (meth) acrylate, flexibility can be imparted to the produced photosensitive dry film resist. Although it does not specifically limit as urethane (meth) acrylate, For example, Aronix M-1100, M-1310 (made by Toagosei), Karayad UX-4101 (made by Nippon Kayaku) etc. can be mentioned.

  By using imide (meth) acrylate, the adhesiveness to the base material (for example, a polyimide film, copper foil, etc.) to which the photosensitive dry film resist produced is bonded can be improved. Although it does not specifically limit as an imide (meth) acrylate, For example, Aronix TO-1534, TO-1429, TO-1428 (made by Toagosei) can be mentioned.

  Furthermore, the (meth) acrylic compound other than those described above is not particularly limited, but in order to improve the crosslinking density by light irradiation, a polyfunctional (meth) having at least two carbon-carbon double bonds. It is desirable to use an acrylic compound. Moreover, in order to provide heat resistance to the photosensitive dry film resist obtained, it is preferable to use a compound having at least one aromatic ring and / or heterocyclic ring in one molecule.

  As the (meth) acrylic compound having a carboxyl group and / or a hydroxyl group, CN-131 (Nippon Kayaku), Aronix M-5400, M-5700 (Toagosei), V # 2000, V # 2100, V # 2308, V # 2323 (Osaka Organic Chemical Industry) can also be mentioned.

<(C) Other ingredients>
In the photosensitive resin composition of the present invention, in addition to the above (A) soluble polyimide having a carboxyl group and / or a hydroxyl group and (B) (meth) acrylic compound, (C) other components are included as necessary. It may be contained. Examples of other components include flame retardants, epoxy resins, curing accelerators and / or curing agents, photoreaction initiators and / or sensitizers, polymerization inhibitors, stabilizers, and antioxidants. .

<Flame Retardant>
The photosensitive resin composition of the present invention may contain a flame retardant in order to impart flame retardancy to the cured photosensitive dry film resist. The flame retardant is not particularly limited, but includes phosphorus compounds such as phosphate esters, condensed phosphate esters and phosphine oxides, phosphazene compounds having a phosphorus-nitrogen double bond, and bromine-containing (meth) acrylic compounds. Examples thereof include a bromine organic compound and a silicone compound having a high aromatic ring content. Among these flame retardants, one kind or a combination of two or more kinds may be used.

  The flame retardant is used in an amount of 1 to 100 weights based on 100 parts by weight of the total weight of the soluble polyimide having a carboxyl group and / or hydroxyl group as the component (A) and the epoxy (meth) acrylate as the component (B). It is preferably within the range of 1 part by weight, more preferably within the range of 1 to 50 parts by weight, and particularly preferably within the range of 1 to 40 parts by weight.

  If the flame retardant is less than 1 part by weight relative to 100 parts by weight of the total weight of the photosensitive polyimide resin and the (meth) acrylic compound, a sufficient flame retardant effect may not be obtained. On the other hand, if it exceeds 100 parts by weight, stickiness may be seen in the photosensitive dry film resist in the B stage state, which will be described later, or the resin may easily ooze out during thermocompression bonding, and the physical properties of the cured product may be adversely affected. Since it may give, it is not preferable.

<Epoxy resin>
By using an epoxy resin, the adhesiveness with respect to copper foil, a polyimide film, etc. can be improved to the photosensitive dry film resist produced.

  Although it does not specifically limit as said epoxy resin, For example, bisphenol A type epoxy, such as product name Epicoat 828,834,1001,1002,1003,1004,1005,1007,1010,1100L (Japan Epoxy Resin Co., Ltd. product), etc. Resin, product names ESCN-220L, 220F, 220H, 220HH, 180H65 (Japan Epoxy Resin Co., Ltd.) and other o-cresol novolak type epoxy resins, product name EPPN-502H (Nippon Kayaku Co., Ltd.), etc. Trishydroxyphenylmethane type epoxy resin, naphthalene aralkyl novolak type epoxy resin such as product name ESN-375, novolak type epoxy resin such as product name ESN-185 (Nippon Steel Chemical Co., Ltd.), biphenol type such as product name YX4000H Epoxy tree It can be mentioned.

  In addition to the above, bisphenol A glycidyl ether type epoxy resin, bisphenol F glycidyl ether type epoxy resin, novolac glycidyl ether type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, cyclic aliphatic epoxy resin, aromatic type An epoxy resin, a halogenated epoxy resin, or the like may be used.

  The epoxy resin may be used alone or in combination of two or more. In addition, it is preferable to use the said epoxy resin within the range of 1-100 weight part as needed with respect to 100 weight part of soluble polyimide which has a carboxyl group and / or a hydroxyl group which are (A) components, 1-50 It is more preferable to use within the range of parts by weight, and particularly preferable to use within the range of 2 to 30 parts by weight. If the epoxy resin is less than 1 part by weight, the adhesive property of the resulting photosensitive dry film resist may be reduced. On the other hand, if it exceeds 100 parts by weight, heat resistance and flex resistance may be reduced. is there.

<Curing accelerator and / or curing agent>
When an epoxy resin is used as the material of the photosensitive resin composition, a curing accelerator and / or a curing agent is added to the photosensitive resin composition in order to efficiently cure the photosensitive dry film resist to be produced. Also good. Although it does not specifically limit as such a hardening accelerator and / or a hardening | curing agent, For example, in order to cure | harden an epoxy resin efficiently, an imidazole type compound, an acid anhydride, a tertiary amine, hydrazines And aromatic amines, phenols, triphenylphosphines, and organic peroxides. What is necessary is just to use 1 type or in combination of 2 or more types among these hardening accelerators and / or hardening agents.

  The amount of the curing accelerator and / or curing agent used is preferably in the range of 0.1 to 20 parts by weight with respect to 100 parts by weight of the soluble polyimide having a carboxyl group and / or a hydroxyl group as the component (A). The content is more preferably in the range of 0.5 to 20 parts by weight, and particularly preferably in the range of 0.5 to 15 parts by weight. When the curing accelerator and / or curing agent is less than 0.1 part by weight based on 100 parts by weight of the soluble polyimide having a carboxyl group and / or a hydroxyl group as the component (A), the epoxy resin is sufficiently cured. On the contrary, if it exceeds 20 parts by weight, heat resistance may be lowered.

<Photoinitiator / sensitizer>
When a photosensitive dry film resist formed by adding a photoreaction initiator and / or a sensitizer is exposed, a crosslinking reaction or a polymerization reaction can be promoted in the exposed region. As a result, the solubility of the photosensitive dry film resist in the aqueous developer can be made sufficiently different between the exposed area and the unexposed area. Therefore, the pattern is suitably formed on the photosensitive dry film resist. It becomes possible to develop.

  Examples of the photoreaction initiator include a radical generator, a photocation generator, a photobase generator, and a photoacid generator.

  Although it does not specifically limit as said radical generator, What generate | occur | produces a radical by the light of long wavelength about g line is preferable, for example, 2,2-dimethoxy-1,2-diphenylethane-1-one, 2- Ketone compounds such as hydroxy-2-methyl-1-phenyl-propan-1-one, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, bis (2,6-dimethoxybenzoyl) -2,4 Phosphine oxide compounds such as 4-trimethyl-pentylphosphine oxide, bis (-2,4-cyclopentadien-1-yl) -bis (2,6-difluoro-3- (1H-pyrrol-1-yl) -phenyl) Examples thereof include titanocene compounds such as titanium. In particular, it is preferable to use a phosphine oxide compound or a titanocene compound.

  Examples of the photocation generator include diphenyliodonium salts such as diphenylanthraquinone sulfonic acid diphenyliodonium salt, triphenylsulfonium salts, pyririnium salts, triphenylonium salts, diazonium salts and the like. In addition to the above salts, it is preferable to mix an alicyclic epoxy or vinyl ether compound having high cation curability.

  Further, as the photobase generator, benzyl alcohol-urethane compound obtained by reaction of nitrobenzyl alcohol or dinitrobenzyl alcohol and isocyanate, nitro-1-phenylethyl alcohol, dinitro-1-phenylethyl alcohol and isocyanate can be used. Examples thereof include a phenyl alcohol-urethane compound obtained by the reaction, a propanol-urethane compound obtained by the reaction of dimethoxy-2-phenyl-2-propanol and isocyanate.

  Examples of the photoacid generator include compounds that generate sulfonic acids such as iodonium salts, sulfonium salts, and onium salts, and compounds that generate carboxylic acids such as naphthoquinone diazide. Alternatively, since compounds such as diazonium salts and bis (trichloromethyl) triazines can generate sulfone groups by light irradiation, these compounds can also be preferably used.

  On the other hand, the sensitizer is not particularly limited. However, Mihiraketone, bis-4,4′-diethylaminobenzophenone, 3,3′-carbonylbis (7-diethylamino) coumarin, 2- (p-dimethylaminostyryl) quinoline. 4- (p-dimethylaminostyryl) quinoline and the like.

  The said photoinitiator and / or sensitizer can be used 1 type or in combination of 2 or more types.

  The amount of the photoinitiator and / or sensitizer used is the total weight of the soluble polyimide having the carboxyl group and / or hydroxyl group as the component (A) and the epoxy (meth) acrylate as the component (B) of 100 weight. It is preferably within the range of 0.001 to 10 parts by weight, and more preferably within the range of 0.01 to 10 parts by weight with respect to parts. If the amount of the photoinitiator and / or sensitizer used is less than 0.001 parts by weight or more than 10 parts by weight, no sensitization effect can be obtained, which adversely affects developability. There is a possibility of effect.

  A radical generator and a sensitizer may be used in combination, but from the viewpoint of easy availability, a peroxide such as bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide and 3,3 ′ , 4,4′-Tetra (t-butylperoxycarbonyl) benzophenone is preferred.

<Polymerization inhibitor, stabilizer, antioxidant>
The photosensitive resin composition of the present invention includes (A) a soluble polyimide having a carboxyl group and / or a hydroxyl group, and (B) a vinyl group, an acrylic group, a methacryl group, etc. contained in addition to the (meth) acrylic compound. In order to prevent the photopolymerizable / thermopolymerizable functional group from undergoing a crosslinking reaction during storage of the photosensitive resin composition and the photosensitive dry film resist, selected from the group consisting of a polymerization inhibitor, a stabilizer and an antioxidant. It is preferred to add at least one polymer additive.

The polymerization inhibitor is not particularly limited as long as it is generally used as a polymerization inhibitor or a polymerization inhibitor. The stabilizer is not particularly limited as long as it is generally known as a heat stabilizer or a light stabilizer. The antioxidant is not particularly limited as long as it is generally used as an antioxidant or a radical scavenger.
The above polymerization inhibitor, stabilizer and antioxidant are not necessarily separate compounds, and one compound may be used as a polymerization inhibitor or an antioxidant.
Polymer additives selected from the group consisting of polymerization inhibitors, stabilizers and antioxidants are generally used as polymerization inhibitors, polymerization inhibitors, thermal stabilizers, light stabilizers, antioxidants, and radical scavengers. For example, hydroquinone, methyl hydroquinone, 2,5-di-t-butyl hydroquinone, t-butyl hydroquinone, 2,5-bis (1,1,3,3-tetra Hydroquinone compounds such as methylbutyl) hydroquinone (trade name DOHQ, manufactured by Wako Pure Chemical Industries, Ltd.) and 2,5-bis (1,1-dimethylbutyl) hydroquinone (trade name DHHQ, manufactured by Wako Pure Chemical Industries, Ltd.) Benzoquinone compounds such as p-benzoquinone, methyl-p-benzoquinone, t-butylbenzoquinone, 2,5-diphenyl-p-benzoquinone; Taerythritol tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (Ciba Specialty Chemicals Co., Ltd., trade name: Irganox 1010), N, N′-hexane -1,6-diylbis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionamide] (manufactured by the company, trade name: Irganox 1098), 1,3,5-tris (3,5 -Di-t-butyl-4-hydroxybenzyl) -1,3,5-triazine-2,4,6 (1H, 3H, 5H) -trione (product name, Irganox 3114), hydroxyphenol benzotriazole Hindered phenolic compounds such as Asahi Denka Kogyo Co., Ltd., trade name Adeka AO-20; 2- (2H-benzotriazol-2-yl) p-; benzotriazole compounds such as cresol (trade name TINUVIN P, manufactured by Ciba Specialty Chemicals Co., Ltd.); N-nitrosophenylhydroxylamine (trade name Q-1300, manufactured by Wako Pure Chemical Industries, Ltd.) Nitrosamine compounds such as N-nitrosophenylhydroxylamine aluminum salt (trade name Q-1301, manufactured by Wako Pure Chemical Industries, Ltd.); organic sulfur compounds such as phenothiazine, dithiobenzoyl sulfide, dibenzyltetrasulfide; bis (1, 2,2,6,6-pentamethyl-4-piperidyl) [{3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl} methyl] butyl malonate (Ciba Specialty Chemicals ( Co., Ltd., trade name: Irganox 144) and other hindered amine compounds; p- Aromatic amines such as nylenediamine (commonly called paramine) and N, N-diphenyl-p-phenylenediamine; tris (2,4-di-t-butylphenyl) phosphite (trade name: Irganox 168) tetrakis (2 , 4-di-t-butylphenyl) [1,1-biphenyl] -4,4′-diylbisphosphonate (manufactured by the company, trade name: Irganox P-EPQ) and the like.

  In particular, it is particularly preferable to use N-nitrosophenylhydroxylamine and N-nitrosophenylhydroxylamine aluminum salt because they not only exhibit a high polymerization inhibiting effect regardless of the environment but also hardly inhibit UV curing. .

<Method for preparing photosensitive resin composition and method for preparing photosensitive dry film resist>
Then, the preparation method of the photosensitive resin composition and the preparation methods of the photosensitive dry film resist are demonstrated. The photosensitive dry film resist is produced by uniformly applying and drying an organic solvent solution of a photosensitive resin composition on a support film.

<Method for preparing photosensitive resin composition>
First, the preparation method of the photosensitive resin composition of this invention is demonstrated. The photosensitive resin composition of the present invention is a mixture of (A) a soluble polyimide having a carboxyl group and / or a hydroxyl group, (B) a (meth) acrylic compound, and (C) other components as necessary. A solution obtained by uniformly dissolving the organic solvent in an organic solvent is referred to as an organic solvent solution of the photosensitive resin composition. The organic solvent is not particularly limited as long as it is an organic solvent that can dissolve the components contained in the photosensitive resin composition. Examples of the organic solvent include ether solvents such as dioxolane, dioxane, and tetrahydrofuran, ketone solvents such as acetone and methyl ethyl ketone, and alcohol solvents such as methyl alcohol and ethyl alcohol. These organic solvents may be used alone or in combination of two or more. In addition, since the organic solvent is removed in a later step, it is advantageous in terms of the manufacturing process to dissolve the components contained in the photosensitive resin composition and select one having the lowest boiling point as much as possible. .

<Method for producing photosensitive dry film resist>
Then, after apply | coating the organic solvent solution of said photosensitive resin composition uniformly on a support body film, a heating and / or hot air spray are performed. Thereby, the said organic solvent is removed and the photosensitive dry film resist in which the photosensitive resin composition became a film form can be obtained. The photosensitive dry film resist formed in this way is obtained by keeping the photosensitive resin composition in a semi-cured state (B stage). Therefore, when performing thermocompression bonding such as heat laminating, it has appropriate fluidity and can be suitably embedded in the pattern circuit of the printed wiring board. Moreover, after embedding a pattern circuit, it can be hardened completely by performing an exposure process, a thermocompression bonding process, and a heating cure.

  The temperature at which the organic solvent solution of the photosensitive resin composition is dried by performing the above heating and / or hot air blowing is curable such as (meth) acrylic group and epoxy group contained in the photosensitive resin composition. Any temperature at which the group does not react may be used. Specifically, it is preferably 120 ° C. or lower, and particularly preferably 100 ° C. or lower. The drying time is preferably shorter as long as the organic solvent can be removed.

  The material for the support film is not particularly limited, but various commercially available films such as a polyethylene terephthalate (PET) film, a polyphenylene sulfide film, and a polyimide film can be used. Of the above support films, a PET film is often used because it has a certain degree of heat resistance and is relatively inexpensive. In addition, about the joint surface with the photosensitive dry film resist of a support body film, you may use what is surface-treated in order to improve adhesiveness and peelability.

  Furthermore, it is preferable to laminate a protective film on a photosensitive dry film resist prepared by applying a photosensitive resin composition to a support film and drying it. It is possible to prevent dust and dust in the air from adhering and prevent deterioration of quality due to drying of the photosensitive dry film resist.

  The protective film is preferably laminated and laminated on the photosensitive dry film resist surface at a temperature of 10 ° C to 50 ° C. In addition, when the temperature at the time of lamination processing becomes higher than 50 degreeC, the thermal expansion of a protective film will be caused and a wrinkle and a curl may arise in the protective film after a lamination process. In addition, since the said protective film peels at the time of use, it is preferable that the joint surface of a protective film and a photosensitive dry film resist has moderate adhesiveness at the time of storage, and is excellent in peelability.

  Although it does not specifically limit as a material of the said protective film, For example, a polyethylene film (PE film), a polyethylene vinyl alcohol film (EVA film), "the copolymer film of polyethylene and ethylene vinyl alcohol" (following ( "PE + EVA) copolymer film", "PE film and (PE + EVA) copolymer film laminate", or "(PE + EVA) copolymer and polyethylene film by simultaneous extrusion" (one side is PE film) And the other surface is a (PE + EVA) copolymer film surface).

  The PE film has the advantages of being inexpensive and having excellent surface slipperiness. Further, the (PE + EVA) copolymer film has appropriate adhesion to the photosensitive dry film resist and releasability. By using such a protective film, when a three-layer structure sheet having three layers of a protective film, a photosensitive dry film resist, and a support film is wound into a roll, the surface slipperiness is improved. Can do.

<Production of printed wiring board>
A method for producing a printed wiring board formed by forming the photosensitive dry film resist according to the present invention as an insulating protective layer will be described. A case where a CCL formed with a pattern circuit (hereinafter also referred to as a CCL with a circuit) is used as a printed wiring board will be described as an example, but the same technique is used when forming a multilayer printed wiring board. Thus, an interlayer insulating layer can be formed.

  First, the protective film is peeled from the three-layer structure sheet having the protective film, the photosensitive dry film resist, and the support film described above. Below, what peeled the protective film is described as the photosensitive dry film resist with a support film. Then, the CCL with a circuit is covered with the photosensitive dry film resist with a support film and bonded by thermocompression bonding so that the photosensitive dry film resist and the circuit portion of the CCL with circuit are opposed to each other. The bonding by thermocompression bonding may be performed by hot pressing, laminating (thermal laminating), hot roll laminating or the like, and is not particularly limited.

  When the bonding is performed by heat laminating or heat roll laminating (hereinafter referred to as laminating), the processing temperature may be equal to or higher than the lower limit temperature (hereinafter, pressure bonding possible) at which laminating is possible. . Specifically, the temperature at which the pressure bonding is possible is preferably within a range of 50 to 150 ° C., more preferably within a range of 60 to 120 ° C., and particularly preferably within a range of 80 to 120 ° C. preferable.

  When the said process temperature exceeds 150 degreeC, the crosslinking reaction of the photosensitive reactive group contained in the photosensitive dry film resist may arise at the time of a lamination process, and hardening of the photosensitive dry film resist may advance. On the other hand, when the processing temperature is lower than 50 ° C., the fluidity of the photosensitive dry film resist is low, and it becomes difficult to embed the pattern circuit. Furthermore, adhesiveness with the copper circuit of CCL with a copper circuit and the base film of CCL with a copper circuit may fall.

  By the above-described thermocompression treatment, a sample in which a photosensitive dry film resist is laminated on a CCL with a circuit and a support film is further laminated is obtained. Next, pattern exposure and development are performed on the bonded sample. In pattern exposure and development, a photomask pattern is placed on the support film of the bonded sample, and exposure processing is performed through the photomask. Thereafter, the support film is peeled off and development processing is performed, whereby holes (vias) corresponding to the photomask pattern are formed.

  In addition, although the said support body film is peeled off after exposure processing, even if it peels after the photosensitive dry film resist with support body film is bonded together on CCL with a circuit, ie, before performing an exposure process. Good. From the viewpoint of protecting the photosensitive dry film resist, it is preferable to peel off after the exposure process is completed.

  Here, the light source used for exposure is preferably a light source that effectively emits light of 300 to 430 nm. The reason for this is that the photoreaction initiator contained in the photosensitive dry film resist normally functions by absorbing light of 450 nm or less.

  Moreover, as a developing solution used for the development processing, a basic solution in which a basic compound is dissolved may be used. The solvent for dissolving the basic compound is not particularly limited as long as it is a solvent that can dissolve the basic compound, but water is particularly preferable from the viewpoint of environmental problems.

  Examples of the basic compound include hydroxides or carbonates of alkali metals or alkaline earth metals such as sodium hydroxide, potassium hydroxide, sodium carbonate, and sodium bicarbonate, and organic amines such as tetramethylammonium hydroxide. A compound etc. can be mentioned. 1 type may be used for the said basic compound and 2 or more types of compounds may be used for it.

  The concentration of the basic compound contained in the basic solution is preferably in the range of 0.1 to 10% by weight, but from the point of alkali resistance of the photosensitive dry film resist, 0.1 to 5% by weight. % Is more preferable.

  The development processing method is not particularly limited, and examples thereof include a method in which a development sample is placed in a basic solution and stirring, and a method in which a developer is sprayed onto the development sample.

  In the present invention, in particular, a developing process using a spray developing machine using a 1 wt% sodium hydroxide aqueous solution adjusted to a liquid temperature of 40 ° C. as a developer can be exemplified. Here, the spray developing machine is not particularly limited as long as it is an apparatus that sprays a developer on a sample.

  Here, the development time until the pattern of the photosensitive dry film resist can be drawn may be any time as long as the pattern can be drawn, but it is preferable that development is possible in a time of 180 seconds or less, and development is possible in a time of 90 seconds or less. It is most preferable that development can be performed in a time of 60 seconds or less. When the development time exceeds 180 seconds, productivity tends to be inferior.

  Here, as a measure of the development time, there is a method of measuring the dissolution time of the photosensitive dry film resist in the B stage (semi-cured) state. Specifically, a sample in which a photosensitive dry film resist is bonded to a glossy surface of a copper foil is unexposed and a 1 wt% sodium hydroxide aqueous solution (liquid temperature 40 ° C.) is used as a developer, spray pressure. In this method, spray development is performed at 0.85 MPa. By this spray development process, the photosensitive dry film resist is preferably dissolved and removed in a time of 180 seconds or less. When the time until the photosensitive dry film resist is dissolved and removed exceeds 180 seconds, workability tends to be lowered.

  After the exposure / development treatment is performed as described above, the photosensitive dry film resist is completely cured by heating and curing the photosensitive dry film resist. Thereby, the hardened photosensitive dry film resist becomes an insulating protective film of the printed wiring board.

  In addition, when forming a multilayer printed wiring board, the protective layer of the printed wiring board is used as an interlayer insulating layer, and after sputtering, plating, or bonding with a copper foil is further performed on the interlayer insulating layer Then, a pattern circuit may be formed and the photosensitive dry film resist may be laminated as described above. Thereby, a multilayer printed wiring board can be produced.

  In the present embodiment, the case where the photosensitive dry film resist is used as an insulating protective material or an interlayer insulating material for a printed wiring board has been described. However, the photosensitive dry film resist can be used for purposes other than the above.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to these. Preparation of the photosensitive resin composition, specific production examples of the photosensitive dry film resist, and evaluation of physical properties thereof were performed as follows.

<Preparation of photosensitive resin composition>
A soluble polyimide solution was prepared by dissolving (A) a soluble polyimide having a carboxyl group and / or a hydroxyl group in dioxolane and setting the solid content weight% (Sc) = 30%. To this solution, (B) (meth) acrylic compound, and (C) other components as necessary are mixed and stirred, so that the final solid content% by weight (Sc) = 50%. An organic solvent solution of the photosensitive resin composition was prepared. Here, the solid content weight indicates the total weight of materials other than the organic solvent, that is, the components (A), (B), and (C), and the weight of the liquid material other than the organic solvent is included in the weight as the solid content. And

<Preparation of photosensitive dry film resist>
The organic solvent solution of the above photosensitive resin composition was applied to a support film so that the thickness after drying (the thickness of the photosensitive dry film resist) was 20 to 25 μm. As the support film, a PET film (Lumilar manufactured by Toray Industries, Inc., thickness 25 μm) was used. Thereafter, the dioxolane was removed by drying the coating layer on the support film at 100 ° C. for 2 minutes. As a result, a two-layer structure sheet comprising a photosensitive dry film resist / PET film (support film) was obtained. The photosensitive dry film resist layer is in the B stage state.

  Subsequently, a polyethylene film (manufactured by Tamapoly Co., Ltd., GF-1, thickness 40 μm) is rolled on the photosensitive dry film resist layer in the two-layer structure sheet under the conditions of a roll temperature of 20 ° C. and a nip thickness of 75000 Pa · m. By laminating, a three-layer structure sheet having three layers of protective film / photosensitive dry film resist / PET film was obtained.

<Evaluation of physical properties of photosensitive dry film resist>
Regarding the organic solvent solution of the photosensitive resin composition prepared as described above and the manufactured photosensitive dry film resist, the physical properties of the following items were evaluated. Specifically, evaluation was made on developability, heat resistance, and adhesion reliability (humidity resistant environment).

<Developability>
First, electrolytic copper foil (manufactured by Mitsui Kinzoku Co., Ltd., thickness 35 μm) is soft-etched with a 10% by weight sulfuric acid aqueous solution for 1 minute (this is the process of removing the rust inhibitor on the copper foil surface), washed with water, ethanol, acetone The surface was washed with and dried. After peeling off the protective film of the photosensitive dry film resist, it was laminated on the glossy surface of the electrolytic copper foil (after soft etching) under the conditions of 100 ° C. and 75000 Pa · m. A mask pattern depicting fine squares of 100 × 100 μm square and 200 × 200 μm square was placed on the PET film of this laminate, and light having a wavelength of 405 nm was exposed by 300 mJ / cm ² . After peeling off the PET film of this sample, using a spray developing machine (etching machine ES-655D manufactured by Sanhayato Co., Ltd.), a 1 wt% aqueous sodium hydroxide solution (liquid temperature 40 ° C.), spray pressure 0.85 MPa, Development was performed under conditions of a development time of 30 seconds to 180 seconds. The pattern formed by development was then washed with distilled water to remove the developer and dried. If it was observed with an optical microscope and a square of at least 200 μm × 200 μm square was developed, it was judged as acceptable.

<Heat resistance (solder heat resistance)>
Copper foil (electrolytic copper foil manufactured by Mitsui Kinzoku Co., Ltd., thickness 35 μm) was cut into 5 cm square, soft etched with 10 wt% sulfuric acid aqueous solution for 1 minute, washed with water, washed with ethanol and acetone, and then dried. . Next, the protective film of the photosensitive dry film resist cut into 4 cm square was peeled off, and was laminated on the glossy surface of the electrolytic copper foil (after soft etching) and laminated under the conditions of 100 ° C. and 75000 Pa · m. The photosensitive dry film resist surface of this bonded sample was exposed to light of wavelength 405 nm at 1000 mJ / cm ² and then cured by curing at 180 ° C. for 2 hours. After this sample was conditioned 1) in a normal state (24 hours in an environment of 20 ° C./40% relative humidity) and 2) moisture-absorbed (48 hours in an environment of 40 ° C./85% relative humidity), it was applied to a molten solder at 260 ° C. or higher. Soldering was performed by dipping for 30 seconds. If no cracks, blisters, or peeling occurred, the test was accepted.

<Adhesion reliability (humidity resistant environment)>
The photosensitive dry film resist from which the protective film was peeled was overlaid on a polyimide film (manufactured by Kaneka Co., Ltd., trade name: NPI, polyimide film thickness: 25 μm) and laminated under the conditions of 100 ° C. and 75000 Pa · m. The photosensitive dry film resist surface of the bonded sample was exposed to light having a wavelength of 405 nm at 1000 mJ / cm ² , and then the PET film was peeled off and cured by curing at 180 ° C. for 2 hours. The thus prepared “polyimide film / photosensitive coverlay film” laminate sample was placed in a moisture-resistant environment at 85 ° C. and 85% RH for 500 hours, and then the sample was taken out and subjected to a cross-cut peel test. If the photosensitive cover lay film was not peeled off, it was accepted. If the photosensitive cover lay film was peeled off or the film was embrittled, it was rejected.

<Raw materials>
The following commercially available products were used as raw materials for polyimide. Diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride (manufactured by Shin Nippon Rika Co., Ltd., hereinafter referred to as DSDA), 4,4 ′-(4,4′-isopropylidene diphenoxy ) Bisphthalic anhydride (manufactured by GE, hereinafter referred to as BPADA), (2,2′-bis (hydroxyphenyl) propanedibenzoate) -3,3 ′, 4,4′-tetracarboxylic dianhydride (Wakayama Seika Co., Ltd., hereinafter referred to as ESDA), [Bis (4-amino-3-carboxy) phenyl] methane (Wakayama Seika Co., Ltd., hereinafter referred to as MBAA), silicon diamine (Shin-Etsu) Chemical Co., Ltd., product name KF-8010), 2,2′-bis (3-amino-4-hydroxyphenyl) hexafluoropropane (manufactured by Clariant, hereinafter referred to as BIS-AP-AF), bis [4 -(3-amino Phenoxy) phenyl] sulfone (hereinafter referred to as BAPS-M.) Was used.

  Moreover, the weight average molecular weight of the polyimide was calculated in terms of polyethylene oxide by size exclusion chromatography using HLC8220GPC manufactured by Tosoh Corporation.

(Synthesis Example 1: Synthesis of soluble polyimide having carboxyl group)
A 500 ml separable flask equipped with a stirrer was charged with 5.15 g (0.018 mol) of diamine MBAA and 10 g of dimethylformamide (hereinafter also referred to as DMF) to prepare a DMF solution of MBAA. BPADA 7.81 g (0.015 mol), DSDA 5.37 g (0.015 mol), and DMF 15 g were added and vigorously stirred. When the solution became uniform, 1.29 g (0.003 mol) of BAPS-M was further added to the above solution and stirred vigorously. When the solution became homogeneous, finally, 7.47 g (0.009 mol) of silicon diamine KF-8010 was added and vigorously stirred for 1 hour. The polyamic acid solution thus obtained was placed in a vat coated with a fluororesin and dried under reduced pressure in a vacuum oven at 200 ° C. and a pressure of 660 Pa for 2 hours to obtain 27.04 g of a polyimide having a carboxyl group. The weight average molecular weight of this soluble polyimide was 40000. The weight average molecular weight (acid equivalent) per carboxyl group of the soluble polyimide is 722.

(Synthesis Example 2: Introduction of methacryl group into soluble polyimide having carboxyl group)
20.0 g (0.022 mol) of the polyimide having a carboxyl group synthesized in Synthesis Example 1 is dissolved in 40 g of DMF, 1.56 g (0.011 mol) of glycidyl methacrylate, 0.1 g (0.001 mol) of triethylamine, a polymerization inhibitor. As a result, 0.02 g of N-nitrosophenylhydroxylamine aluminum salt was added and stirred at 80 ° C. for 5 hours. This solution was put into 500 ml of methanol, and the precipitated resin was pulverized with a mixer, washed with methanol, and dried to obtain 21.2 g of a polyimide having a methacryl group. The weight average molecular weight of this soluble polyimide was 41,000. The weight average molecular weight (acid equivalent) per carboxyl group of the soluble polyimide is 1511.

(Synthesis Example 3: Synthesis of soluble polyimide having a hydroxyl group)
In a 500 ml separable flask equipped with a stirrer, 76.9 g (0.21 mol) of diamine BIS-AP-AF and 100 g of DMF were added to prepare a DMF solution of BIS-AP-AF. Next, 74.7 g (0.09 mol) of silicon diamine KF-8010 was added to the DMF solution and stirred vigorously. After the solution became homogeneous, 107.5 g (0.30 mol) of DSDA and 300 g of DMF were further added and stirred vigorously for about 1 hour. The polyamic acid solution thus obtained was placed in a vat coated with a fluororesin and dried under reduced pressure in a vacuum oven at 200 ° C. and a pressure of 660 Pa for 2 hours to obtain 251.2 g of a polyimide having a hydroxyl group. The soluble polyimide had a weight average molecular weight of 34,000. The weight average molecular weight (acid equivalent) per hydroxyl group of the soluble polyimide is 591.

(Synthesis Example 4: Synthesis of soluble polyimide having carboxyl group and hydroxyl group)
A 500 ml separable flask equipped with a stirrer was charged with 2.58 g (0.009 mol) of diamine MBAA and 10 g of dimethylformamide (hereinafter also referred to as DMF) to prepare a DMF solution of MBAA. BPADA 7.81 g (0.015 mol), DSDA 5.37 g (0.015 mol) and 15 g of DMF were added and vigorously stirred. When the solution became uniform, 1.29 g (0.003 mol) of BAPS-M was further added to the above solution and stirred vigorously. When the solution became homogeneous, 7.47 g (0.009 mol) of silicon diamine KF-8010 was further added and stirred vigorously for 1 hour. When the solution became homogeneous, finally, BIS-AP-AF (3.30 g, 0.009 mol) was added and vigorously stirred for 1 hour. The polyamic acid solution thus obtained was placed in a vat coated with a fluororesin and dried in a vacuum oven at 200 ° C. and a pressure of 660 Pa for 2 hours to obtain 27.21 g of a polyimide having a carboxyl group and a hydroxyl group. . The soluble polyimide had a weight average molecular weight of 28,000. The weight average molecular weight (acid equivalent) per carboxyl group and / or hydroxyl group of the soluble polyimide is 743.

Example 1
<Preparation of photosensitive dry film resist>
15 g of the polyimide synthesized in Synthesis Example 1 was dissolved in 35 g of dioxolane to prepare an organic solvent solution having a solid content of% by weight (Sc) = 30%.

  The components shown below were mixed to prepare an organic solvent solution of the photosensitive resin composition, and a photosensitive dry film resist in a B-stage state was prepared.

(A) Soluble polyimide ・ Polyimide synthesized in Synthesis Example 1 (in terms of solid content) 100 parts by weight (B) (Meth) acrylic compound ・ Modified bisphenol A type epoxy acrylate (Daicel UCB) , Product name Ebecryl 3708) ... 50 parts by weight (C) Other components As a photoinitiator,
Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (Irgacure 819 manufactured by Ciba Specialty Chemicals Co., Ltd.) 2 parts by weight as an epoxy resin
-Bisphenol A type epoxy resin (product name: Epicoat 828, manufactured by Japan Epoxy Resin Co., Ltd.) 30 parts by weight As a curing agent,
・ 4,4′-diaminodiphenylmethane (DDM) ・ ・ ・ 1 part by weight <Evaluation results of physical properties>
The physical property evaluation results of the obtained photosensitive dry film resist were as follows.
Developability: Both 100 μm × 100 μm square holes and 200 μm × 200 μm square holes were developed and passed.
Heat resistance: Passes both normal and moisture absorption.
Adhesion reliability: pass Table 1 summarizes the results.

(Example 2)
<Preparation of photosensitive dry film resist>
15 g of the polyimide synthesized in Synthesis Example 2 was dissolved in 35 g of dioxolane to prepare an organic solvent solution having a solid content of% by weight (Sc) = 30%.
The components shown below were mixed to prepare an organic solvent solution of the photosensitive resin composition, and a photosensitive dry film resist in a B-stage state was prepared.

(A) Soluble polyimide ・ Polyimide synthesized in Synthesis Example 2 (in terms of solid content) 100 parts by weight (B) (Meth) acrylic compound ・ Bisphenol A type epoxy acrylate (manufactured by Daicel UCB) Product name Ebecryl 3700) ··· 20 parts by weight · Urethane acrylate (manufactured by Nippon Kayaku, product name CN-980) ··· 30 parts by weight (C) Other components As a photoreaction initiator,
・ Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (Irgacure 819 manufactured by Ciba Specialty Chemicals) ・ ・ ・ 2 parts by weight As an epoxy resin,
-Bisphenol A type epoxy resin (product name: Epicoat 828, manufactured by Japan Epoxy Resin Co., Ltd.) ... 10 parts by weight <Evaluation results of physical properties>
The physical property evaluation results of the obtained photosensitive dry film resist were as follows.
Developability: Both 100 μm × 100 μm square holes and 200 μm × 200 μm square holes were developed and passed.
Heat resistance: Passes both normal and moisture absorption.
Adhesion reliability: pass Table 1 summarizes the results.

(Example 3)
<Preparation of photosensitive dry film resist>
15 g of polyimide synthesized in Synthesis Example 3 was dissolved in 35 g of dioxolane to prepare an organic solvent solution having a solid content of% by weight (Sc) = 30%.

  The components shown below were mixed to prepare an organic solvent solution of the photosensitive resin composition, and a photosensitive dry film resist in a B-stage state was prepared.

(A) Soluble polyimide-Polyimide synthesized in Synthesis Example 3 (converted as solid content) ... 100 parts by weight (B) (Meth) acrylic compound-Bisphenol A EO modification (repeat unit m + n of ethylene oxide modification site) ≒ 30) Diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., product name NK Ester A-BPE-30) ... 20 parts by weight · Imidoacrylate (manufactured by Toagosei, product name Aronix TO-1429) ·· ... 10 parts by weight-Urethane acrylate (product name CN-980, manufactured by Nippon Kayaku Co., Ltd.) ... 30 parts by weight (C) Other components As a photoreaction initiator,
・ Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (Irgacure 819 manufactured by Ciba Specialty Chemicals) ・ ・ ・ 2 parts by weight As an epoxy resin,
-Bisphenol A type epoxy resin (product name: Epicoat 828, manufactured by Japan Epoxy Resin Co., Ltd.) ... 10 parts by weight <Evaluation results of physical properties>
The physical property evaluation results of the obtained photosensitive dry film resist were as follows.
Developability: Both 100 μm × 100 μm square holes and 200 μm × 200 μm square holes were developed and passed.
Heat resistance: Passes both normal and moisture absorption.
Adhesion reliability: pass Table 1 summarizes the results.

Example 4
<Preparation of photosensitive dry film resist>
15 g of the polyimide synthesized in Synthesis Example 4 was dissolved in 35 g of dioxolane to prepare an organic solvent solution having a solid content of% by weight (Sc) = 30%.

  The components shown below were mixed to prepare an organic solvent solution of the photosensitive resin composition, and a photosensitive dry film resist in a B-stage state was prepared.

(A) Soluble polyimide ・ Polyimide synthesized in Synthesis Example 4 (converted in terms of solid content) 100 parts by weight (B) (Meth) acrylic compound ・ Modified bisphenol A type epoxy acrylate (manufactured by Daicel UCB) Product name Ebecryl 3708) ··· 60 parts by weight · Bisphenol A type epoxy acrylate (Daicel UCB, product name Ebecryl 3700) ··· 5 parts by weight · Imido acrylate (product of Toagosei Co., Ltd., product name Aronix) TO-1429) ... 10 parts by weight (C) Other components As a photoreaction initiator,
・ Bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide (Irgacure 819 manufactured by Ciba Specialty Chemicals) ・ ・ ・ 2 parts by weight As an epoxy resin,
-Bisphenol A type epoxy resin (product name: Epicoat 828, manufactured by Japan Epoxy Resin Co., Ltd.) 20 parts by weight <Results of evaluating physical properties>
The physical property evaluation results of the obtained photosensitive dry film resist were as follows.
Developability: Both 100 μm × 100 μm square holes and 200 μm × 200 μm square holes were developed and passed.
Heat resistance: Passes both normal and moisture absorption.
Adhesion reliability: pass Table 1 summarizes the results.

(Comparative Example 1)
<Synthesis of base polymer>
The polymer component having the largest content in the photosensitive resin composition used in place of the polyimide having a carboxyl group and / or a hydroxyl group as the component (A) is referred to as a base polymer.

(Synthesis of polyimide resin)
A 500 ml separable flask equipped with a stirrer was charged with 173 g (0.30 mol) of ESDA and 300 g of DMF to prepare a DMF solution of ESDA. Next, a solution prepared by dissolving 86.5 g (0.20 mol) of BAPS-M in 100 g of DMF was added to the DMF solution, and the mixture was vigorously stirred. After the solution became uniform, 83.5 g (0.10 mol) of silicon diamine KF-8010 was added and stirred vigorously for 1 hour.

  The polyamic acid solution thus obtained was placed in a vat coated with a fluororesin and dried under reduced pressure in a vacuum oven at 200 ° C. and a pressure of 660 Pa for 2 hours to obtain 315 g of polyimide. This polyimide does not have a carboxyl group or a hydroxyl group in the imide resin, and no photosensitive group is introduced.

<Preparation of photosensitive dry film resist>
15 g of the polyimide synthesized above was dissolved in 35 g of dioxolane to prepare an organic solvent solution having a solid content of% by weight (Sc) = 30%.

  A photosensitive dry film resist was produced under exactly the same conditions except that the polyimide synthesized above was used as the base polymer instead of the component (A) of Example 1.

<Evaluation results of physical properties>
The physical property evaluation results of the obtained photosensitive dry film resist were as follows.
Developability: Both 100 μm × 100 μm square holes and 200 μm × 200 μm square holes were not developed and failed.
Heat resistance: Passes both normal and moisture absorption.
Adhesion reliability: pass Table 1 summarizes the results.

  Thus, when the polyimide which does not have a carboxyl group and / or a hydroxyl group is used as a base polymer, although heat resistance and adhesion reliability were favorable, developability was bad.

(Comparative Example 2)
<Synthesis of base polymer>
As raw materials, monomers of methyl methacrylate, n-butyl methacrylate, 2-ethylhexyl acrylate, and methacrylic acid were used. These monomer components were copolymerized using a known method to obtain a carboxyl group-containing copolymer. The polymerization ratio of each monomer component at this time was methyl methacrylate / n-butyl methacrylate / 2-ethylhexyl acrylate / methacrylic acid = 60/10/10/20 (weight basis).

<Preparation of photosensitive dry film resist>
A photosensitive dry film resist was produced under exactly the same conditions as in Example 2 except that the acrylic copolymer synthesized above was used as the base polymer instead of the component (A) in Example 2.

<Evaluation results of physical properties>
The physical property evaluation results of the obtained photosensitive dry film resist were as follows.
Developability: Both 100 μm × 100 μm square holes and 200 μm × 200 μm square holes were developed and passed.
Heat resistance: Both normal and moisture absorption are rejected.
Adhesion reliability: pass Table 1 summarizes the results.

  As described above, when an acrylic copolymer synthesized from a monomer having a structure having no aromatic ring is used as a base polymer, the developability is good, but the heat resistance is inferior.

(Comparative Example 3)
(Synthesis of polyimide resin)
In a 500 ml separable flask equipped with a stirrer, 76.9 g (0.21 mol) of diamine BIS-AP-AF and 100 g of DMF were added to prepare a DMF solution of BIS-AP-AF. Next, 74.7 g (0.09 mol) of silicon diamine KF-8010 was added to the DMF solution and stirred vigorously. After the solution became uniform, 173.0 g (0.30 mol) of ESDA and 300 g of DMF were further added and stirred vigorously for about 1 hour. The polyamic acid solution thus obtained was placed on a vat coated with a fluororesin and dried under reduced pressure in a vacuum oven at 200 ° C. and a pressure of 660 Pa for 2 hours to obtain 317.2 g of a polyimide having a hydroxyl group. The weight average molecular weight of this polyimide was 36000. The weight average molecular weight (acid equivalent) per carboxyl group and / or hydroxyl group of this soluble polyimide is 871. Although this polyimide has a hydroxyl group in the imide resin, DSDA (diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride) is not used as a part of the raw material.

<Preparation of photosensitive dry film resist>
15 g of the polyimide synthesized above was dissolved in 35 g of dioxolane to prepare an organic solvent solution having a solid content of% by weight (Sc) = 30%.

  A photosensitive dry film resist was prepared under exactly the same conditions except that the polyimide synthesized above was used as the base polymer instead of the component (A) of Example 3.

<Evaluation results of physical properties>
The physical property evaluation results of the obtained photosensitive dry film resist were as follows.
Developability: Both 100 μm × 100 μm square holes and 200 μm × 200 μm square holes were developed and passed.
Heat resistance: Passes both normal and moisture absorption.
Adhesion reliability: There was peeling of the coverlay about 5%, and it failed.

  Table 1 summarizes the results.

  Thus, when polyimide which does not use DSDA as a part of the raw material is used, the adhesion reliability may be inferior.

Claims (6)

(A) A photosensitive resin composition comprising a soluble polyimide having a carboxyl group and / or a hydroxyl group, and (B) a (meth) acrylic compound, wherein the soluble polyimide as the component (A) is A photosensitive resin composition, which is a soluble polyimide using diphenylsulfone-3,4,3 ′, 4′-tetracarboxylic dianhydride as a part of a raw material. The soluble polyimide as the component (A) has at least one carbon-carbon double bond selected from the group consisting of an acryl group, a methacryl group, a vinyl group, and an allyl group. The photosensitive resin composition as described. The photosensitive resin composition according to claim 1 or 2, wherein the soluble polyimide as the component (A) has a weight average molecular weight of 10,000 or less per carboxyl group and / or hydroxyl group. The photosensitive dry film resist produced using the photosensitive resin composition in any one of Claims 1-3. When a 1% by weight sodium hydroxide aqueous solution is used as an aqueous developer at 40 ° C. and a spray developing machine is used as a developing means, the dissolution time under a spray pressure of 0.85 MPa is 180 seconds or less. The photosensitive dry film resist according to claim 4, wherein: 6. A printed wiring board, wherein the photosensitive dry film resist according to claim 4 is used as an insulating protective layer.