JP5379506B2 - Photosensitive resin composition and circuit board using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alkali developable photosensitive resin composition which does not produce byproduct resulting from a photo-base generator and requires no curing at a high temperature, unlike a conventional photosensitive resin composition, and to provide a circuit board using the composition. <P>SOLUTION: The photosensitive resin composition contains a photo-base generator (A) and a polyamide acid (B). The photo-base generator contains a cyclic compound expressed by formula (1), containing a photocleavable moiety in the cyclic structure. In formula (1), X<SP>1</SP>represents an arylane group; n represents an integer of 0 to 3; and R<SP>1</SP>represents an aromatic group or a 2-50C alkyl group. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a novel photosensitive resin composition using a photobase generator and a circuit board using the same.

  Polyimide resins are applied in various fields based on excellent properties such as high insulation, heat and cold resistance, and high strength. In recent years, polyimides have been used as base materials and coverlays in flexible printed wiring boards (hereinafter abbreviated as FPCs) that are remarkably elongated. FPCs are required to be finer in line with the recent advancement and density of IC mounting technology, and high workability is also required for coverlays using polyimide.

  In manufacturing the FPC, the polyimide base material is mechanically punched, and the alignment is performed for bonding. Therefore, there is a problem that the alignment accuracy cannot be increased. In order to solve this problem, a photosensitive film based on a solder resist film using an acrylate resin or an epoxy resin has been studied. However, in terms of physical properties such as flexibility, it was not as good as polyimide (for example, patents). Literatures 1-3).

  There is also a proposal of a photosensitive resin composition using a polyamic acid ester having a photosensitive group in the side chain. In this case, after development, the photosensitive group in the side chain is decomposed by high-temperature curing at about 300 ° C. to 450 ° C. It is necessary to imidize (for example, Patent Document 4). When these photosensitive polyamic acid esters are used as an FPC coverlay, there is a concern that curing at a high temperature may damage the circuit board.

  As photosensitive polyamic acid using a photobase generator, a positive photosensitive resin composition using nitrobenzyl carbamate as a photobase generator, or a negative type using a photobase generator having an acyloxyimino group. There is a proposal of a photosensitive resin composition (for example, Patent Documents 5 and 6).

  However, since conventionally known acyclic photobase generators exist after photocleavage, the radical species are divided into two molecules, so that the radical species diffuse to each other, reducing the probability of recoupling, The generation efficiency decreases. For this reason, it is necessary to add about 100 parts by mass of the photobase generator to 100 parts by mass of the resin, and there is a concern that the mechanical properties of the film are deteriorated. In addition, by-products of aldehyde compounds and ketone compounds are formed as completely separated molecules together with amines. In the negative photolithography process, the produced by-product is likely to be eluted into the developer and cause a reduction in film thickness. Further, when the by-product is highly volatile, there is a concern that it may cause odor and contaminate the optical system of photolithography. In view of this point, there is a proposal of a cyclic photobase generator (for example, Patent Document 7) in which a molecular design without a by-product is performed, but these do not necessarily satisfy heat-resistant stability. There is a concern about the mechanical properties of the film when the film made of the photosensitive resin composition is used as the photosensitive coverlay.

Japanese Patent Laid-Open No. 56-6498 JP-A 61-243869 JP-A-6-332171 Japanese Patent Laid-Open No. 2001-194783 Japanese Patent No. 3363580 JP-A-6-295063 JP 2008-003581 A

  The present invention has been made in view of the above points, and by improving the heat resistance stability of the photobase generator, it has been difficult to achieve with conventional photosensitive resin compositions, and has improved photomechanical properties. It aims at providing a resin composition and a circuit board using the same.

The photosensitive resin composition of the present invention is a photosensitive resin composition containing a photobase generator (A) and a polyamic acid (B), and the photobase generator is represented by the formula (1). And a compound containing an acyloxyimino group.

（式中、Ｘ¹はアリーレン基であり、ｎは０〜３の整数を表す。Ｒ^１は芳香族基または炭素数が２以上のアルキル基である。）

(In the formula, X ¹ is an arylene group, and n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.)

  In the photosensitive resin composition of the present invention, the photobase generator is a compound containing an acyloxyimino group represented by formula (1), and the compound is represented by formula (2) or formula (3). It is preferred that

（式中、ｎは０〜３の整数を表す。Ｒ^１は芳香族基または炭素数が２以上のアルキル基である。）

(In the formula, n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.)

（式中、ｎは０〜３の整数を表す。Ｒ^１は芳香族基または炭素数が２以上のアルキル基である。）

(In the formula, n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.)

  In the photosensitive resin composition of this invention, it is preferable that the said polyamic acid is a polyamic acid obtained using the diamine represented by Formula (4).

（式中Ｒ^ａは炭素数が１〜５０の２価の有機基である。ｋは１〜５０の数を表す。）

(In the formula, R ^a is ^a divalent organic group having 1 to 50 carbon atoms. K represents a number of 1 to 50.)

  In the photosensitive resin composition of the present invention, the polyamic acid is preferably a polyamic acid obtained by using an acid dianhydride represented by the formula (5).

（式中ｌは１〜２０の数を表す。ｍは２〜５０の整数を表す。）

(In the formula, l represents a number of 1 to 20. m represents an integer of 2 to 50.)

  In the photosensitive resin composition of this invention, it is preferable that the said polyamic acid is a polyamic acid obtained using the diamine represented by Formula (6) further.

（式中、Ｚは２価の有機基であり、式（７）に示す有機基から選ばれる。）

(In the formula, Z is a divalent organic group and is selected from the organic groups shown in Formula (7).)

（式中ｐは３から５の整数を表す。）

(Wherein p represents an integer of 3 to 5)

  In the photosensitive resin composition of the present invention, the polyamic acid is preferably a polyamic acid obtained by using oxydiphthalic dianhydride.

  In the photosensitive resin composition of this invention, it is preferable to contain a photosensitizer (C) further.

  In the photosensitive resin composition of this invention, it is preferable to contain a flame retardant (D) further.

  In the photosensitive resin composition of this invention, it is preferable to contain a plasticizer (E) further.

  The photosensitive film of this invention was comprised with the said photosensitive resin composition, It is characterized by the above-mentioned.

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

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

  The circuit board of the present invention is characterized by comprising a substrate having wiring and a cover lay configured using the photosensitive film or the laminated film.

  The method for producing a circuit board of the present invention includes a step of forming a resin composition layer on a substrate having at least wiring using the photosensitive resin composition, and a step of performing pattern exposure on the resin composition layer. And a step of developing the resin composition layer after pattern exposure using an alkaline aqueous solution and a step of curing the resin composition layer after the development processing.

  In the method for producing a circuit board of the present invention, at least a step of laminating at least one of the photosensitive film or the laminated film on a substrate having wiring to form a resin composition layer, and the resin composition A step of performing pattern exposure on the layer, a step of developing the resin composition layer after the pattern exposure using an alkaline aqueous solution, and a step of curing the resin composition layer after the development processing. It is preferable.

  Since the photosensitive resin composition of the present invention contains a photobase generator (A) containing a cyclic compound containing a photocleavage site in the cyclic structure, it is possible to use an alkali which does not liberate the ketone produced as a by-product. A soluble photosensitive polyamic acid resin composition can be provided. Furthermore, since an arylene group is contained in the cyclic structure and an aromatic group or an alkyl group having 2 or more carbon atoms is introduced into a substituent outside the cyclic structure, the heat resistance stability is improved. By the molecular design of these photobase generators, it is possible to provide a photosensitive resin composition with improved mechanical properties of a film, which has been difficult with conventional photobase generators, and a circuit board using the same.

Embodiments of the present invention will be described in detail.
The photobase generator (A) according to the present invention can be decomposed satisfactorily with respect to light having a wavelength of 200 nm to 500 nm to generate a base. At that time, since the acyloxyimino group in the photobase generator according to the present invention is included in the cyclic structure, the radical species generated by the photocleavage reaction are linked by a covalent bond, and a by-product is generated. do not do. Furthermore, the photobase generator according to the present invention has a radical recoupling efficiency higher than that of an acyclic photobase generator because radical species generated after cleavage by light are covalently bonded to each other. It is possible to improve the generation efficiency of the base.

  The photobase generator in the present invention is a compound containing an acyloxyimino group represented by the formula (1).

（式中、Ｘ¹はアリーレン基であり、ｎは０〜３の整数を表す。Ｒ^１は芳香族基または炭素数が２以上のアルキル基である。）

(In the formula, X ¹ is an arylene group, and n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.)

  Since the photobase generator in the present invention contains an arylene group in the cyclic structure, the thermal decomposability is improved. It is presumed that this is because thermal motion is suppressed by introducing an arylene group into the cyclic structure.

In the formula (1), the arylene group represented by X ¹ is not particularly limited, and examples thereof include a phenylene group and a naphthylene group. These groups are preferable from the viewpoint of light absorption. In formula (1), n is preferably 0 to 3 from the viewpoint of radical coupling efficiency after cleavage of the photobase generator with light. In Formula (1), R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms, and among these, an aromatic group or an alkyl group having 2 to 50 carbon atoms is preferable.

Since the photobase generator introduces an aromatic group or an alkyl group having 2 or more carbon atoms into the substituent R ¹ outside the cyclic structure, the heat scattering property is reduced. It is presumed that this is because a bulky aromatic group or an alkyl group having 2 or more carbon atoms prevents the volatilization of the molecule.

  An aromatic group is, for example, a phenyl group or a naphthyl group. These may have a substituent. Examples of the substituent that the aromatic group may have include a methyl group, an ethyl group, a propyl group, an i-propyl group, an n-butyl group, an i-butyl group, an s-butyl group, a t-butyl group, Examples include phenoxy group, methoxy group, ethoxy group, n-butoxy group, i-butoxy group, s-butoxy group, t-butoxy group and the like. These substituents contribute to improving the solubility in the polymer varnish.

  Examples of the alkyl group having 2 or more carbon atoms include propyl group, i-propyl group, n-butyl group, i-butyl group, s-butyl group, t-butyl group, phenoxy group, methoxy group, ethoxy group, n -Butoxy group, i-butoxy group, s-butoxy group, t-butoxy group and the like can be mentioned. These alkyl groups having 2 or more carbon atoms are preferred from the viewpoint of suppressing heat scattering.

Among these substituents R ¹ , since the conjugation with the acyloxyimino group is extended, an aromatic group is particularly preferable from the viewpoint of contributing to improvement of photodegradability.

Among the compounds containing an acyloxyimino group represented by formula (1), compounds represented by formula (2) and formula (3) are preferred. These are preferable from the viewpoints of heat stability and photodegradability. Further, R ¹ in the formulas (2) and (3) represents an aromatic group or an alkyl group having 2 or more carbon atoms, and among these, an aromatic group or an alkyl group having 2 to 50 carbon atoms. Is preferred.

（式中、ｎは０〜３の整数を表す。Ｒ^１は芳香族基または炭素数が２以上のアルキル基である。）

(In the formula, n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.)

（式中、ｎは０〜３の整数を表す。Ｒ^１は芳香族基または炭素数が２以上のアルキル基である。）

(In the formula, n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.)

  These thermal decomposition improvements and thermal stability improvements due to improved thermal scattering properties do not cause deterioration of the physical properties of the film when the film is cured by heat treatment after development (hereinafter simply referred to as cure). preferable.

  The amount of the photobase generator in the photosensitive resin composition is preferably 1 to 50 parts by mass with respect to 100 parts by mass of polyamic acid in consideration of photosensitivity and mechanical properties of the resin after curing. . More preferably, it is 2 mass parts-30 mass parts. Particularly preferred is 3 to 20 parts by mass.

  In the photosensitive resin composition according to the present invention, a photobase generator and a known photobase generator may be used in combination. Known photobase generators include, for example, acyclic acyloxyimino compounds, acyclic carbamoyloxime compounds, carbamoylhydroxylamine compounds, carbamic acid compounds, formamide compounds, acetamide compounds, carbamate compounds, benzyl carbamate compounds, nitrobenzyl carbamates. Compounds, sulfonamide compounds, imidazole derivative compounds, amine imide compounds, pyridine derivative compounds, α-aminoacetophenone derivative compounds, quaternary ammonium salt derivative compounds, α-lactone ring derivative compounds, amine imide compounds, phthalimide derivative compounds, and the like can be used. . Of these, acyloxyimino compounds having relatively high amine generation efficiency are preferred. The addition of a known photobase generator is preferably as small as possible.

  Next, the polyamic acid (B) will be described. There is no restriction | limiting in particular about the polyamic acid which concerns on this invention, A well-known polyamic acid can be used. For example, the polyamic acid can be obtained using diamine and tetracarboxylic dianhydride as raw materials.

  The polyamic acid according to the present invention is preferably synthesized using a diamine represented by the formula (4) as a diamine, particularly from the viewpoint of low warpage of the substrate.

（式中Ｒ^ａは炭素数が１〜５０の２価の有機基である。ｋは１〜５０の数を表す。）

(In the formula, R ^a is ^a divalent organic group having 1 to 50 carbon atoms. K represents a number of 1 to 50.)

The diamine represented by the general formula (4) is not particularly limited as long as it is a diamine having o-, m-, and p-aminobenzoic acid ester groups at both ends, but both ends are p-aminobenzoic acid esters. The group is more preferred. In formula (4), k is a number from 1 to 50, and more preferably, k is a number from 3 to 25. In formula (4), R ^a is a C 1-50 divalent organic group. Specifically, R ^a is preferably a divalent organic group represented by the formula (8).

式（４）で表されるジアミンの具体例としては、例えばポリテトラメチレンオキシド−ジ−ｏ−アミノベンゾエート、ポリテトラメチレンオキシド−ジ−ｍ−アミノベンゾエート、ポリテトラメチレンオキシド−ジ−ｐ−アミノベンゾエート、ポリトリメチレンオキシド−ジ−ｏ−アミノベンゾエート、ポリトリメチレンオキシド−ジ−ｍ−アミノベンゾエート、ポリトリメチレンオキシド−ジ−ｐ−アミノベンゾエート等が挙げられるが、これらに限定されない。ジアミンを２種以上、使用しても良い。好ましくは、ポリテトラメチレンオキシド−ジ−ｐ−アミノベンゾエートである。

Specific examples of the diamine represented by the formula (4) include, for example, polytetramethylene oxide-di-o-aminobenzoate, polytetramethylene oxide-di-m-aminobenzoate, polytetramethylene oxide-di-p-amino. Examples include, but are not limited to, benzoate, polytrimethylene oxide-di-o-aminobenzoate, polytrimethylene oxide-di-m-aminobenzoate, polytrimethylene oxide-di-p-aminobenzoate. Two or more diamines may be used. Polytetramethylene oxide-di-p-aminobenzoate is preferable.

  It is preferable that the polyamic acid which concerns on this invention contains 10 mol%-55 mol% of diamine represented by Formula (4) with respect to all the diamines. More preferably, it is 15 mol%-50 mol%. If content of diamine represented by Formula (4) is 15 mol% or more with respect to all the diamine, it will be excellent in low curvature and low resilience.

  In addition to the diamine represented by the formula (4), as another diamine that can be used in the present invention, for example, a diamine represented by the formula (6) is preferable from the viewpoint of alkali solubility and low warpage.

（式中、Ｚは２価の有機基であり、式（７）に示す有機基から選ばれる。）

(In the formula, Z is a divalent organic group and is selected from the organic groups shown in Formula (7).)

（式中ｐは３から５の整数を表す。）

(Wherein p represents an integer of 3 to 5)

  Specific examples of the diamine represented by the formula (6) include 3,3′-diaminodiphenyl ether, 3,4′-diaminodiphenyl ether, 4,4′-diaminodiphenyl ether, and 1,3-bis (3-aminophenoxy). ) Benzene, 1,4-bis (4-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 3,3′-diaminodiphenylsulfone, 4,4′-diaminodiphenylsulfone, 1,3 -Bis (4-aminophenoxy) propane, 1,4-bis (4-aminophenoxy) butane, 1,5-bis (4-aminophenoxy) heptane.

  It is preferable that the polyamic acid which concerns on this invention contains 10 mol%-90 mol% of diamine represented by Formula (6) with respect to all the diamines. More preferably, it is 20 mol%-85 mol%. When the content of the diamine represented by the formula (6) is 20 mol% or more with respect to the total diamine, the mechanical properties of the cured film are excellent.

  In addition to these diamines, examples of other diamines that can be used in the present invention include aromatic diamines, aliphatic diamines, diamines having a carboxyl group, diamines having a hydroxyl group, and diamines having a siloxane skeleton.

  As aromatic diamines, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, 3,3′- Diaminodiphenyldifluoromethane, 4,4'-diaminodiphenyldifluoromethane, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl sulfide, 3,3'-diaminodiphenyl ketone 3,4′-diaminodiphenyl ketone, 4,4′-diaminodiphenyl ketone, 2,2-bis (3-aminophenyl) propane, 2,2- (3,4′-diaminodiphenyl) propane, 2,2 -Bis (4-aminophenyl) propane, 2, -Bis (3-aminophenyl) hexafluoropropane, 2,2- (3,4'-diaminodiphenyl) hexafluoropropane, 2,2-bis (4-aminophenyl) hexafluoropropane, 3,3 '-[ 1,4-phenylenebis (1-methylethylidene)] bisaniline, 3,4 ′-[1,4-phenylenebis (1-methylethylidene)] bisaniline, 4,4 ′-[1,4-phenylenebis (1 -Methylethylidene)] bisaniline, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4- (4-aminophenoxy) phenyl] propane, 2,2-bis [4 -(3-aminophenoxy) phenyl] hexafluoropropane, 2,2-bis [4- (4-aminophenoxy) phenyl] hexafluoropropane Bread, bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (4-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (4 -Aminophenoxy) phenyl] sulfone.

  Examples of the aliphatic diamine include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,5-diaminopentane, 1,6-diaminohexane, 1,7-diaminoheptane, 1, Examples include 8-diaminooctane, 1,9-diaminononane, 1,10-diaminodecane, and 1,11-diaminoundecane.

  Examples of the diamine having a carboxyl group include 3,3'-dicarboxy-4,4'-diaminodiphenylmethane and 3,5-diaminobenzoic acid.

  Examples of the diamine having a hydroxyl group include 1,2-diamino-4-hydroxybenzene, 1,3-diamino-5-hydroxybenzene, 1,3-diamino-4-hydroxybenzene, 1,4-diamino-6-hydroxybenzene. 1,5-diamino-6-hydroxybenzene, 1,3-diamino-4,6-dihydroxybenzene, 1,2-diamino-3,5-dihydroxybenzene, 4- (3,5-diaminophenoxy) phenol, 3- (3,5-diaminophenoxy) phenol, 2- (3,5-diaminophenoxy) phenol, 3,3′-dihydroxy-4,4′-diaminobiphenyl, 3,3′-diamino-4,4 ′ -Dihydroxybiphenyl, 2,2-bis (4-hydroxy-3-aminophenyl) propane, 2,2-bis (4-hydride) Xyl-3-aminophenyl) hexafluoropropane, bis (4-hydroxy-3-aminophenyl) ketone, 2,2-bis (4-hydroxy-3-aminophenyl) sulfide, 2,2-bis (4-hydroxy) -3-aminophenyl) ether, 2,2-bis (4-hydroxy-3-aminophenyl) sulfone, 2,2-bis (4-hydroxy-3-aminophenyl) methane, 4-[(2,4- Diamino-5-pyrimidinyl) methyl] phenol, p- (3,6-diamino-s-triazin-2-yl) phenol, 2,2-bis (4-hydroxy-3-aminophenyl) difluoromethane, 2,2 -Bis (4-amino-3-hydroxyphenyl) propane, 2,2-bis (4-amino-3-hydroxyphenyl) hexafluoropropa Bis (4-amino-3-hydroxyphenyl) ketone, 2,2-bis (4-amino-3-hydroxyphenyl) sulfide, 2,2-bis (4-amino-3-hydroxyphenyl) ether, 2, 2-bis (4-amino-3-hydroxyphenyl) sulfone, 2,2-bis (4-amino-3-hydroxyphenyl) methane, 2,2-bis (4-amino-3-hydroxyphenyl) difluoromethane Can be mentioned.

  These diamines having a carboxyl group or a hydroxyl group can be used from the viewpoint of improving alkali solubility.

  Examples of the diamine having a siloxane skeleton include α, ω-bis (2-aminoethyl) polydimethylsiloxane, α, ω-bis (3-aminopropyl) polydimethylsiloxane, α, ω-bis (4-aminobutyl) poly. Examples thereof include dimethylsiloxane, α, ω-bis (4-aminophenyl) polydimethylsiloxane, α, ω-bis (3-aminopropyl) polydiphenylsiloxane, and the like. These diamines can be used alone or in combination.

  The polyamic acid according to the present invention is preferably an acid dianhydride represented by the formula (5) as an acid dianhydride from the viewpoint of low warpage of the substrate.

（式中ｌは１〜２０の数を表す。ｍは２〜５０の整数を表す。）

(In the formula, l represents a number of 1 to 20. m represents an integer of 2 to 50.)

  Specifically, ethylene glycol-bis-trimellitic anhydride ester, 1,3-propanediol-bis-trimellitic anhydride ester, butanediol-bis-trimellitic anhydride ester, pentanediol-bis-trimellitic anhydride Acid ester, heptanediol-bis-trimellitic anhydride ester, decanediol-bis-trimellitic anhydride ester. It is also preferable to use a mixture of two or more of these. Preferred are ethylene glycol-bis-trimellitic anhydride ester, pentanediol-bis-trimellitic anhydride ester, and decanediol-bis-trimellitic anhydride ester. More preferably, a combination of ethylene glycol-bis-trimellitic anhydride and pentanediol-bis-trimellitic anhydride, or ethylene glycol-bis-trimellitic anhydride and decandiol-bis-trimellitic anhydride It is a combination with an acid ester.

  As the acid dianhydride used in the present invention, other acid dianhydrides other than those of the formula (5) can be used, and among them, oxydiphthalic acid dianhydride is preferable from the viewpoint of improving developability.

  Other acid dianhydrides that can be used in the present invention besides these acid dianhydrides include, for example, aromatic tetracarboxylic dianhydrides, alicyclic tetracarboxylic dianhydrides, aliphatic tetracarboxylic dianhydrides Things.

  Examples of aromatic tetracarboxylic dianhydrides include pyromellitic dianhydride, 3,3′4,4′-biphenyltetracarboxylic dianhydride, 2,2 ′, 3,3′-biphenyltetracarboxylic dianhydride. Anhydride, 2,3,3 ′, 4′-biphenyltetracarboxylic dianhydride, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3- Dicarboxyphenyl) propane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, 1,1-bis (3,4-dicarboxyphenyl) ethane dianhydride, bis (2 , 3-Dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 3,4,9,10- Perylene tetraca Boronic acid dianhydride, bis (3,4-dicarboxyphenyl) ether dianhydride, benzene-1,2,3,4-tetracarboxylic dianhydride, 3,3 ′, 4,4′-benzophenone tetra Carboxylic dianhydride, 2,2 ′, 3,3′-benzophenone tetracarboxylic dianhydride, 2,3,3 ′, 4′-benzophenone tetracarboxylic dianhydride, 1,2,5,6- Naphthalenetetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,4,5-naphthalenetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetra Carboxylic dianhydride, 2,6-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 2,7-dichloronaphthalene-1,4,5,8-tetracarboxylic dianhydride Thing, 2, 3, 6, 7 Tetrachloronaphthalene-1,4,5,8-tetracarboxylic dianhydride, phenanthrene-1,8,9,10-tetracarboxylic dianhydride, bis (3,4-dicarboxyphenyl) dimethylsilane dianhydride Bis (3,4-dicarboxyphenyl) methylphenylsilane dianhydride, bis (3,4-dicarboxyphenyl) diphenylsilane dianhydride, 1,4-bis (3,4-dicarboxyphenyldimethylsilyl) ) Benzene dianhydride, 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyldicyclohexane dianhydride, p-phenylenebis (trimellitic acid monoester anhydride) ), 2,2-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride, 2,2-bis [4- (3,4-dicarboxyphenyl) Enoxy) phenyl] hexafluoropropane dianhydride, 2,2-bis [4- (3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 4,4-bis (3,4-dicarboxyphenoxy) diphenyl And sulfide dianhydrides.

  Examples of the alicyclic tetracarboxylic dianhydride include 1,5-cyclooctadiene-1,2,5,6-tetracarboxylic dianhydride, 5-carboxymethylbicyclo [2.2.1] heptane- 2,3,6-tricarboxylic acid-2,3: 5,6-dianhydride, 1-carboxymethyl-2,3,5-cyclopentanetricarboxylic acid-2,6: 3,5-dianhydride, bicyclo [2.2.2] Oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, 5- (2,5-dioxotetrahydro-3-furanyl) -3-methyl-3- Cyclohexene-1,2-dicarboxylic anhydride, tetrahydrofuran-2,3,4,5-tetracarboxylic dianhydride, 4- (2,5-dioxotetrahydrofuran-3-yl) -1,2,3 4-tetrahydronaphthalene-1, Dicarboxylic anhydride, decahydronaphthalene-1,4,5,8-tetracarboxylic dianhydride, 4,8-dimethyl-1,2,3,5,6,7-hexahydronaphthalene-1,2 , 5,6-tetracarboxylic dianhydride, cyclopentane-1,2,3,4-tetracarboxylic dianhydride, pyrrolidine-2,3,4,5-tetracarboxylic dianhydride, 1,2 , 3,4-cyclobutanetetracarboxylic dianhydride, bis (exo-bicyclo [2.2.1] heptane-2,3-dicarboxylic anhydride) sulfone.

  Examples of the aliphatic tetracarboxylic dianhydride include ethylene tetracarboxylic dianhydride and 1,2,3,4-butanetetracarboxylic dianhydride. These tetracarboxylic dianhydride components can be used alone or in combination.

  The polyamic acid according to the present invention can be synthesized by mixing the diamine and the tetracarboxylic dianhydride in an arbitrary solvent to obtain a polyamic acid solution. As a method for producing a polyamic acid according to the present invention, all methods capable of producing a polyamic acid, including known methods, can be applied. Among these, it is preferable to perform the reaction in an organic solvent. As a solvent used in such a reaction, for example, N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, γ-butyrolactone, 1,2-dimethoxyethane, tetrahydrofuran, 1,3 -Dioxane, 1,4-dioxane, dimethyl sulfoxide, benzene, toluene, xylene, mesitylene, phenol, cresol and the like. These may be used alone or in combination of two or more.

  The density | concentration of the reaction raw material in this reaction is 2 mass%-50 mass% normally, Preferably it is 5 mass%-40 mass%.

  The reaction temperature is usually 80 ° C. or lower, preferably 70 ° C. or lower. The reaction pressure is not particularly limited, and can be sufficiently carried out at normal pressure. Moreover, although reaction time changes with the kind of reaction raw material, the kind of solvent, and reaction temperature, 0.5 to 24 hours are sufficient normally. By such a polycondensation reaction, the polyamic acid according to the present invention is produced.

  The molar ratio of the acid dianhydride to be reacted and the diamine is in the range of 0.8 to 1.2. Within this range, the molecular weight can be increased, and the elongation and the like are excellent. Preferably it is 0.9-1.1.

  The photosensitive resin composition according to the present invention may further contain a photosensitizer (C). When a photosensitizer is included, the decomposition of the photobase generator can be promoted, which is effective in reducing the exposure amount. There is no restriction | limiting in particular as a photosensitizer, A well-known photosensitizer can be used. For example, aromatic azides such as azidoanthraquinone and azidobenzalacetophenone; coumarin compounds such as coumarin, ketocoumarin, and 3,3′-carbonylbis (diethylaminocoumarin); benzanthrone, phenontolenquinone, benzyl, benzophenone, p aromatic ketones such as p′-tetramethyldiaminobenzophenone; N-phenyldiethanolamine, N-phenylglycine, p-nitroaniline, 2,4-dinitroaniline, 2-chloro-4-nitroaniline, 2, Aromatic amines such as 6-dinitro-4-nitroaniline, Michler-ketone; thioxanthone compounds such as thioxanthone, diethylthioxanthone, isopropylthioxanthone; anthracene, naphthalene, diphenyl, p-nitrodipheny It is anthraquinone, naphthoquinone, quinones such as benzoquinone and the like; aromatic hydrocarbons such as.

  In addition, for example, a coumarin compound having a heterocyclic ring described in JP-A-3-239703 and JP-A-5-289335; 3-ketocoumarin compound described in JP-A 63-221110; Xanthene dyes described in JP-A Nos. 221958 and 4-219756; pyromethene dyes described in JP-A No. 6-19240; JP-A Nos. 47-2528 and 54-155292 (P-dialkylaminobenzylidene) ketone and styryl dye described in JP-A-56-166154 and JP-A-59-56403; having a julolidyl group described in JP-A-6-295061 Sensitizing dyes; and diaminobenzene compounds described in JP-A-11-326624. Kill.

  Of these, compounds having absorption in the vicinity of 300 nm to 450 nm are preferable, and specifically, benzophenones, coumarin compounds, thioxanthone compounds, aromatic ketones, and Michler ketones are preferable.

  The amount of the photosensitizer to be used is not particularly limited, but it is preferable to blend 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the polyamic acid in consideration of photosensitivity and mechanical properties of the resin after curing. . More preferably, it is 3 mass parts-30 mass parts.

  The photosensitive resin composition according to the present invention may further contain a flame retardant (D). The photosensitive resin composition according to the present invention can be further improved in flame retardancy by adding a flame retardant component. There is no restriction | limiting in particular as a flame retardant, A well-known flame retardant can be used.

  The flame retardant component is preferably a phosphorus-based flame retardant, and among them, a phosphate ester compound and / or a phosphazene compound are preferable from the viewpoint of flexibility and flexibility of the photosensitive resin composition. Among the phosphate ester compounds or phosphazene compounds, cyclic phosphazene compounds are more preferable from the viewpoint of heat stability.

  As the phosphoric acid ester compound, an aromatic phosphoric acid ester, an alkyl phosphoric acid ester or an alkoxyphosphoric acid ester is preferable.

  Examples of the aromatic phosphate ester include triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, triisopropylphenyl phosphate, resorcinol bis (diphenyl phosphate) (hereinafter also referred to as “RDP”) and the like.

  Examples of the alkyl phosphate ester include triethyl phosphate, tripropyl phosphate, tributyl phosphate, triisobutyl phosphate (hereinafter also referred to as “TIBP”), and the like.

  Examples of the alkoxyphosphate include tris (butoxyethyl) phosphate, tris (butoxybutyl) phosphate (hereinafter also referred to as “TBXP”), tris (2-ethylhexyl) phosphate, and the like.

  As the phosphazene compound, a cyclic compound is preferable from the viewpoint of heat stability. For example, a compound selected from compounds represented by formula (9) is preferable.

（式中、Ｘはそれぞれ３〜５の数を表す。）

(In the formula, each X represents a number of 3 to 5.)

  These flame retardant components can be used alone or in combination.

  The photosensitive resin composition according to the present invention may further contain a plasticizer (E). The photosensitive resin composition according to the present invention can be further improved in low warpage by adding a plasticizer component.

  Although there is no restriction | limiting in particular as a plasticizer, From the viewpoint of low curvature, the plasticizer containing an ethylene glycol chain and / or a propylene glycol chain is preferable. More preferred is a compound having an ethylene glycol chain and / or a propylene glycol chain and an isocyanuric acid ring from the viewpoint of flame retardancy. For example, the compound shown by Formula (10) etc. are mentioned.

（式中Ｒ^ｂはエチレングリコール鎖及び／又はプロピレングリコール鎖を含む有機基である。）

(In the formula, R ^b is an organic group containing an ethylene glycol chain and / or a propylene glycol chain.)

Specifically, for example, an organic group represented by the formula (11) is preferable as R ^b .

（式中、式中ｎ’は２〜８の数を表す。Ｌ’は２〜８の数を表す。）

(In the formula, n ′ represents a number of 2 to 8. L ′ represents a number of 2 to 8.)

  To the photosensitive resin composition according to the present invention, additives that are already known can be added as necessary within a quantitative and qualitative range that does not depart from the effects of the present invention. Specific additives include adhesion improvers, surfactants, antioxidants, UV inhibitors, light stabilizers, plasticizers, waxes, fillers, pigments, dyes, foaming agents, antifoaming agents, dehydration Agents, antistatic agents, antibacterial agents, antifungal agents, leveling agents, dispersants, ethylenically unsaturated compounds and the like.

  Examples of the adhesion improver include imidazole compounds, triazole compounds, tetrazole compounds, and sulfide compounds, preferably 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, and 2-ethyl-4-methylimidazole. 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-methylimidazole, 1 Examples include silicon-containing imidazoles such as -cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, and imidazolesilane. As imidazole silane, for example, IM-1000 manufactured by Nikko Metal Co., Ltd. is preferable.

  The photosensitive resin composition according to the present invention can be obtained by mixing a photobase generator, polyamic acid and, if necessary, a photosensitizer, a flame retardant and a plasticizer in an arbitrary solvent. The photosensitive resin composition according to the present invention may be in the form of a solution, but it is preferable to form a film. When forming a film, it can be obtained by mixing a photobase generator, polyamic acid and, if necessary, a photosensitizer, a flame retardant and a plasticizer in an arbitrary solvent and then drying by an arbitrary method. it can.

  The photosensitive resin composition according to the present invention can be suitably used for a photosensitive ink or a photosensitive film. When the photosensitive resin composition of the present invention is used for a photosensitive ink or a photosensitive film, negative photolithography is possible.

  When the photosensitive resin composition according to the present invention is used as a photosensitive ink, it can be applied on an arbitrary substrate by screen printing and then dried to form a coverlay on the arbitrary substrate. The screen printing method is a known printing method in which ink is passed through a screen on which a pattern is formed using a squeegee or the like.

  When using the photosensitive resin composition which concerns on this invention for a photosensitive film, first, the photosensitive resin composition which concerns on this invention is coated on a base material, and a photosensitive film is created. The substrate is not limited as long as it is a substrate that is not damaged during the formation of the photosensitive film. Such a substrate is used as a carrier film.

  Examples of the carrier film include a heat resistant resin, a polyethylene terephthalate film, and a metal film. Among these, a heat-resistant resin and a polyethylene terephthalate film are preferable from the viewpoint of good handling, and a polyethylene terephthalate film is particularly preferable from the viewpoint of peelability after pressure bonding to the substrate.

  The photosensitive film comprised with the photosensitive resin composition which concerns on this invention can be processed into the laminated film which comprises a carrier film. The laminated film may include a cover film.

  The coating of the photosensitive resin composition on the carrier film is performed by, for example, bar coating, roller coating, die coating, blade coating, dip coating, doctor knife, spray coating, flow coating, spin coating, slit coating, brush coating, etc. It can be carried out. After coating, if necessary, heat treatment is performed with an oven, a hot plate, etc., and the solvent is dried to form a laminated film having a carrier film and a photosensitive film.

  Moreover, it is good also as a laminated | multilayer film by providing at least one layer of arbitrary antifouling or protective cover films on the photosensitive film according to the present invention. In the laminated film according to the present invention, as the cover film, for example, any antifouling film such as low-density polyethylene or a protective film can be used.

  By forming the photosensitive film according to the present invention as described above on a base material having wiring so as to cover the wiring, a circuit board having a cover lay can be formed on the base material. it can. In addition to the above photosensitive film, a circuit board can be similarly formed by using a laminated film provided with a carrier film and a photosensitive film or a laminated film further provided with a cover film on the laminated film. .

  The cover lay formed on an arbitrary substrate formed by using the photosensitive ink or the photosensitive film by the above method is subjected to a treatment such as curing through at least exposure and alkali development steps.

  A circuit board can be manufactured using the photosensitive resin composition according to the present invention. In this method of manufacturing a circuit board, a circuit board is manufactured, a photosensitive resin composition is applied onto a substrate having at least wiring, and then dried to form a resin composition layer, and pattern exposure is performed on the resin composition. The resin composition layer after pattern exposure is developed using an alkaline aqueous solution, and the resin composition layer after the development treatment is cured.

  In the method for producing a circuit board, at least either the photosensitive film or the laminated film is laminated on a substrate having wiring to form a resin composition layer, and a pattern is formed on the resin composition layer. Exposure is performed, the resin composition layer after the pattern exposure is developed using an aqueous alkaline solution, and the resin composition layer after the development treatment is cured.

  As a base material which has wiring, what has wiring on arbitrary base materials, such as hard base materials, such as a glass epoxy board | substrate and a glass maleimide board | substrate, or flexible substrates, such as a polyimide film, is mentioned. Among these, the base material which has wiring on a flexible board | substrate from a viewpoint which can be bent is preferable.

  As a method for forming the resin composition layer, the screen printing method described above is preferably used when a photosensitive ink is used.

  When using a photosensitive film, the method etc. which perform a hot press, a heat | fever lamination, a heat | fever vacuum press, a heat | fever vacuum lamination etc. in the state which contacted the wiring side and the photosensitive film of the base material which has the said wiring are mentioned. Among these, from the viewpoint of embedding the photosensitive film between the wirings, a heat vacuum press or a heat vacuum laminate is preferable. The heating temperature when laminating the photosensitive film on the substrate having the wiring is not limited as long as the photosensitive film can be in close contact with the substrate. 30 to 400 degreeC is preferable from a viewpoint of contact | adherence to a base material, a decomposition | disassembly of a photosensitive film, or a side reaction. More preferably, it is 50 degreeC-150 degreeC.

  The cover lay according to the present invention is subjected to a heat treatment (hereinafter referred to as PEB) as necessary after exposure and before development, and then the unexposed portion is dissolved by alkali development, whereby a negative photo Lithography is possible. In this case, examples of the light source used for exposure include a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, a xenon lamp, a fluorescent lamp, a tungsten lamp, an argon laser, and a helium cadmium laser. Among these, a high pressure mercury lamp and an ultrahigh pressure mercury lamp are preferable.

  The temperature at which PEB is carried out is preferably 100 ° C. to 160 ° C. from the viewpoint of developability. Heating may be performed in either an air atmosphere or a nitrogen atmosphere. Moreover, there is no restriction | limiting in particular as a heating method, However, It can carry out using oven, a baking furnace, a hotplate, etc.

  The aqueous alkali solution used for development is not limited as long as it is a solution capable of dissolving the unexposed portion. Examples of such a solution include a sodium carbonate aqueous solution, a potassium carbonate aqueous solution, a sodium hydroxide aqueous solution, a potassium hydroxide aqueous solution, and a tetramethylammonium hydroxide aqueous solution. From the viewpoint of developability, an aqueous sodium carbonate solution and an aqueous sodium hydroxide solution are preferred. Examples of the development method include spray development, immersion development, and paddle development.

  Next, the circuit board having the cover lay is formed by curing the circuit board on which the cover lay of the present invention is formed as necessary. The curing is preferably performed at a temperature of 30 ° C. to 400 ° C. from the viewpoint of removing the solvent, side reactions and decomposition, and not damaging the wiring on the substrate. More preferably, 100 to 200 ° C is preferable. More preferably, it is 120 degreeC-180 degreeC. Cure may be performed in either an air atmosphere or a nitrogen atmosphere. The curing method is not particularly limited, but can be performed using an oven, a baking furnace, a hot plate, or the like.

  The mechanism in which the difference in solubility and / or the difference in dissolution rate between the exposed portion and the unexposed portion of the photosensitive resin composition according to the present invention is estimated as follows. Since the base generated from the photobase generator upon exposure acts as an imidization catalyst when converting polyamic acid to polyimide, the imidization ratio of the exposed part is higher than that of the unexposed part, Solubility and / or dissolution rate in alkaline developer is reduced.

  At that time, imidation reaction can be promoted by applying PEB. By performing alkali development using the solubility and / or dissolution rate in the alkaline developer, negative photolithography in which the exposed portion remains undissolved in the developer can be achieved.

  The photosensitive resin composition according to the present invention is sufficiently suppressed in warping as a cover lay, has good developability, and exhibits chemical resistance when cured and cured, so that it is used in the electronics field. Forming protective layers for printed wiring boards and circuit boards used for operation panels of various electronic devices, forming insulating layers for laminated substrates, silicon wafers used for semiconductor devices, semiconductor chips, members around semiconductor devices, and semiconductor mounting It is used to form films on electronic components for use in protecting, insulating and bonding substrates, heat sinks, lead pins, semiconductors, etc.

  Next, examples performed for clarifying the effects of the present invention will be described.

<Reagents for Photobase Generator Synthesis Example>
In the photobase generator synthesis example, α-tetralone (manufactured by Tokyo Chemical Industry Co., Ltd.), 1-indanone (manufactured by Tokyo Chemical Industry Co., Ltd.), phenylmagnesium bromide (manufactured by Tokyo Chemical Industry Co., Ltd.), methyl magnesium bromide ( Tokyo Chemical Industry Co., Ltd.), p-toluenesulfonic acid (Tokyo Chemical Industry Co., Ltd.), sodium periodate (Wako Pure Chemical Industries, Ltd.), ruthenium (III) chloride hydrate (Wako Pure Chemical Industries, Ltd.), Hydroxyl ammonium chloride (manufactured by Wako Pure Chemical Industries, Ltd.), 50% hydroxylamine aqueous solution (manufactured by Wako Pure Chemical Industries, Ltd.), 2,4,6, -trichlorobenzoyl chloride (manufactured by Tokyo Chemical Industry Co., Ltd.), triethylamine (Wako Pure Chemical Industries, Ltd.) 4-dimethylaminopyridine (manufactured by Tokyo Chemical Industry Co., Ltd.), 5-benzoylpentanoic acid (manufactured by Tokyo Chemical Industry Co., Ltd.), thiochloride Le (manufactured by Wako Pure Chemical Industries, Ltd.) was used for the reaction without carrying out any special purification.

<Photobase generator synthesis example 1>
(Process 1)
Under a nitrogen stream, α-tetralone (5.0 g / 34.2 mmol) and isopropyl ether (70 ml) were placed in a 200 ml two-necked flask and stirred in an ice bath. After dropwise addition of phenylmagnesium bromide (34.2 ml / 68.4 mmol) using a syringe, a white suspension was formed. After stirring for 3 hours, saturated brine was added for washing, followed by drying over sodium sulfate. After drying, the solvent was distilled off with an evaporator, and the precipitate was collected.

(Process 2)
The precipitate collected in Step 1, methylene chloride (34 ml) and p-toluenesulfonic acid (2.0 g / 10.5 mmol) were placed in a two-necked flask and stirred at room temperature for 3 hours. Saturated saline was added for washing, followed by drying over sodium sulfate. After drying, the solvent was distilled off with an evaporator, and the precipitate was collected.

(Process 3)
A precipitate (2.0 g / 9.7 mmol), sodium periodate (10.6 g / 50.0 mmol), and ruthenium (III) chloride hydrate (2.0 mg / 9.7 mmol) collected in Step 2 in a one-necked flask equipped with a reflux tube ( 0.2 g / 0.97 mmol), acetonitrile (18 ml), hexane (24 ml) and water (18 ml) were added and stirred in a water bath. After stirring for 4 hours, the resulting brown suspension was extracted with methylene chloride and 2N hydrochloric acid. The organic layer was removed and extracted with 10% aqueous sodium hydroxide. The aqueous layer was taken out, 2N hydrochloric acid was added, and the mixture was extracted with methylene chloride. The organic layer was taken out, washed with water and saturated brine, and dried over sodium sulfate. After drying, the solvent was distilled off with an evaporator, and the precipitate was collected.

(Process 4)
The precipitate (0.93 g / 3.67 mmol) obtained in Step 3 obtained in an eggplant flask equipped with a reflux tube, hydroxylammonium chloride (2.42 g / 34.8 mmol), and sodium hydroxide (4.4 g / 110 mmol), water (12 ml) and ethylene glycol (12 ml) were added and heated under reflux conditions for 5 hours. After cooling to room temperature, 2N hydrochloric acid was added, the organic layer and the aqueous layer were separated, and the organic layer was extracted with methylene chloride. The extracted organic layer was washed with saturated brine and then purified by recrystallization from hexane and methylene chloride, and the resulting crystals were collected.

(Process 5)
Crystals recovered in Step 4 in an eggplant flask under a nitrogen stream (1.02 g / 3.78 mmol), 2,4,6, -trichlorobenzoyl chloride (2.77 g / 11.3 mmol) and triethylamine (1.91 g / 18.9 mmol) and tetrahydrofuran (38 ml) were added, and after stirring for 1 hour at room temperature, a white suspension was obtained. The obtained white suspension was filtered, and the filtrate was added dropwise to toluene (380 ml) to which 4-dimethylaminopyridine (9.24 g / 75.6 mmol) was added, and stirred at room temperature for 12 hours. Saturated saline was added to the resulting suspension for good washing, and then dried over sodium sulfate. The solvent was distilled off with an evaporator, and the resulting solid was recrystallized with hexane and ethyl acetate, and the precipitated crystals were collected. The obtained compound was identified as Formula (12) by 1H-NMR and GC-MS. The resulting compound is hereinafter referred to as PBG-1.

<Photobase generator synthesis example 2>
Synthesis was carried out under the same conditions as in Photobase Generator Synthesis Example 1 except that 1-indanone was used instead of α-tetralone as the raw material in Photobase Generator Synthesis Example 1 (Step 1). It was. The obtained compound was identified as Formula (13) by 1H-NMR and GC-MS. The resulting compound is hereinafter referred to as PBG-2.

<Photobase generator synthesis comparative example 1>
Synthesis was carried out under the same conditions as in Photobase Generator Synthesis Example 1 except that methylmagnesium bromide was used instead of phenylmagnesium bromide as the raw material for Photobase Generator Synthesis Example 1 (Step 1) to obtain a compound. . The obtained compound was identified as Formula (14) by 1H-NMR and GC-MS. The resulting compound is hereinafter referred to as PBG-3.

<Photobase generator synthesis comparative example 2>
5-Benzoylpentanoic acid (7.5 g / 36 mmol), hydroxylammonium chloride (3.75 g / 53.94 mmol), methanol (30 ml) were placed in a flask, and an aqueous solution containing KOH (5.6 g / 100 mmol) (15 ml) The mixture was heated at 60 ° C. for 10 minutes with stirring, cooled to room temperature, cooled in an ice bath, and neutralized with a 1.2N aqueous hydrochloric acid solution. The precipitated white solid was recrystallized with toluene to obtain (5.4 g / 24 mmol) of 6-hydroxyimino-6-phenylhexanoic acid.

  The obtained 6-hydroxyimino-6-phenylhexanoic acid (3.06 g / 13.8 mmol), pyridine (45 ml) and diethyl ether (60 ml) were placed in a flask and cooled to −20 ° C. to −30 ° C. Then, diethyl ether (120 ml) containing thionyl chloride (1.20 ml / 16.4 mmol) (manufactured by Wako Pure Chemical Industries, Ltd.) was added dropwise with stirring. After stirring at room temperature overnight, the solvent was distilled off with an evaporator. (50 ml) of chloroform was added to the precipitate, and this chloroform solution was washed with a 1.2N hydrochloric acid aqueous solution, a saturated sodium hydrogen carbonate aqueous solution and a saturated brine, and dried over sodium sulfate. After drying, chloroform was distilled off with an evaporator, and the resulting pale yellow solid was separated by column chromatography to obtain a photobase generator represented by the formula (15). The resulting compound is hereinafter referred to as PBG-4.

<Photobase generator synthesis comparative example 3>
Phenylacetyl chloride (15.46 g / 0.10 mol) (manufactured by Tokyo Chemical Industry Co., Ltd.) and acetophenone oxime (14.87 g / 0.11 mol) were dissolved in chloroform, and triethylamine was added in 1.1 times mol of acetophenone oxime. After stirring at room temperature for 3 hours, a small amount of water was added, and then the reaction solution was thoroughly washed with water and saturated brine. After distilling off the solvent with an evaporator, the crude product was purified with cyclohexane-ethyl acetate and the precipitate was collected to obtain a photobase generator of formula (16). The obtained compound is hereinafter referred to as PBG-5.

<Reagent used for polyamic acid synthesis example>
In the polyamic acid synthesis example, the reagents used are oxydiphthalic dianhydride (manac), pentanediol-bis-trimellitic anhydride (manufactured by Kurokin Kasei, trade name: 5BTA), polytetramethylene oxide -Di-p-aminobenzoate (manufactured by Ihara Chemical Industry, trade name: Elastomer 1000, average molecular weight 1238), 1,3-bis (3-aminophenoxy) benzene (manufactured by Wakayama Seika Co., Ltd.) are subjected to special purification Used in the reaction without.

<Example of polyamic acid synthesis>
In a 1-liter separable flask equipped with a stirrer, γ-butyrolactone (20 g), oxydiphthalic dianhydride (1.70 g / 5.5 mmol), and pentanediol-bis-trimellitic anhydride were added under a nitrogen stream. An ester (4.07 g / 9 mmol) was added, and 1,3-bis (3-aminophenoxy) benzene (2.25 g / 7.7 mmol) was added while stirring at room temperature, and then heated to 60 ° C. for 10 minutes. Stir. Oxydiphthalic dianhydride (1.70 g / 5.5 mmol), γ-butyrolactone (17.2 g), polytetramethylene oxide-di-p-aminobenzoate (3.96 g / 3.2 mmol) and 1,3-bis (3-Aminophenoxy) benzene (2.25 g / 7.7 mmol) was added and stirred for 1 hour. When the reaction liquid became brown and transparent, the reaction liquid was cooled to room temperature and recovered by pressure filtration using a filter paper having a pore size of 10 μm to obtain a polyamic acid solution (polyamic acid content 30% by mass). The number average molecular weight was about 15,000 and the weight average molecular weight was about 42,000. This polyamic acid solution was used as it was for the production of a photosensitive resin composition (hereinafter referred to as polyamic acid B1).

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

<Reagents for formulation examples>
In the formulation examples, 2,4-diethyl-9H-thioxanthen-9-one (manufactured by Wako Pure Chemical Industries, Ltd.) (hereinafter referred to as DETX), which is the reagent used, is a compound (Fushimi Pharmaceutical Co., Ltd.) Product name: Rabitol FP-100) (hereinafter referred to as FP-100) and the compound represented by formula (18) (trade name: Sample C, manufactured by Toho Chemical Co., Ltd.) (hereinafter referred to as Sample C) are specially purified. Were used in the formulation.

（表１中、（Ｂ）成分の配合量はポリアミド酸溶液中に含まれるポリアミド酸の値である。） <Photosensitive resin composition formulation example>

(In Table 1, the blending amount of component (B) is the value of the polyamic acid contained in the polyamic acid solution.)

<Photosensitive resin composition film production>
The resin composition varnish produced with the formulation shown in Table 1 above was coated on a 25 μm thick PET film (R-310-25 / Mitsubishi Chemical Polyester Film Co., Ltd.) with a blade coater, and then an oven (ESPEC) at 95 ° C./12 minutes. The product was dried with SPHH-10l) to obtain a laminated film composed of a PET film and a photosensitive resin composition. The thickness of the film layer composed of the photosensitive resin composition was 20 μm in any combination. Hereinafter, the film layer comprised with the photosensitive resin composition is described with the photosensitive film.

<Film thickness measurement>
The film thickness was measured using a film thickness meter (ID-C112B, manufactured by Mitutoyo).

<FPC coverlay production>
Film lamination was performed using a vacuum press (manufactured by Tester Sangyo Co., Ltd.). The press temperature was 100 ° C., the press pressure was 0.5 MPa, and the press time was 1 minute. After laminating the photosensitive film on the FPC substrate under the above conditions, the PET film was peeled off. The photosensitive film layer obtained on the FPC substrate is referred to as a photosensitive coverlay.

<Examples of photolithography evaluation>
The obtained photosensitive cover lay was subjected to contact exposure with an ultra-high pressure mercury lamp (trade name: HMW-201KB, manufactured by Oak Corporation) using a negative mask. The exposure amount was 1000 mJ / cm ² in Example 1, Example 3, and Comparative Example 1, and 500 mJ / cm ² in Example 2, Comparative Example 2, and Comparative Example 3. After the exposure, it was heated in an oven at 110 ° C. for 20 minutes. The development was performed with a 1% sodium carbonate aqueous solution at a development temperature of 30 ° C. and a spray pressure of 0.2 MPa. Spray water washing was performed with distilled water at 30 ° C. under a spray pressure of 0.2 MPa, and the resulting pattern was observed with an optical microscope. The evaluation was made with ○ indicating that a 100 μm circular hole pattern could be formed and × indicating that pattern formation was difficult.

<Example of Cure Film Low Warpage Evaluation>
The evaluation of the warpage was carried out by laminating a photosensitive film on a Kapton (Toray DuPont, registered trademark, film thickness 25 μm) film under the above-mentioned laminating conditions and 1,000 mJ on both sides without using a photomask by the above-described method. / Cm < ² > exposure was performed. Next, curing was performed by a method described later to prepare a sample. When the prepared sample was cut out to a size of 50 mm × 50 mm and allowed to stand on a horizontal surface, the case where the hem portion floated was 10 mm or less was marked as ◯, and the case where it was larger than 10 mm was marked as x.

<Example of evaluation of cured film mechanical properties>
A photosensitive film is laminated on the copper surface of an unpatterned FPC (manufactured by Nippon Steel Chemical Co., Ltd., trade name: Espanex, polyimide 20 μm / copper 12 μm) under the above lamination conditions to obtain a photosensitive coverlay. By this method, exposure of 1,000 mJ / cm ² was performed on both surfaces without using a photomask. Next, curing was performed by a method described later to prepare a sample. The obtained sample was folded, and the sample that could be folded 10 times or more without cracking or peeling was marked with ◯, and the sample with 9 times or less was marked with x.

<Cure>
95 ° C / 12 minutes oven (ESPEC, SPHH-10l) Kapton film laminated with photosensitive film or FPC substrate laminated with photosensitive coverlay at 120 ° C for 1 hour, then at 180 ° C for 1 hour The heat treatment was performed.

<Cure film flame retardant test results>
The photosensitive resin composition is coated on one side of the Kapton film by the above-mentioned coating method and dried at 95 ° C. for 12 minutes, and then the photosensitive resin composition is coated on the opposite side and dried at 95 ° C. for 12 minutes. Then, after coating the photosensitive resin composition on both sides of the Kapton film, exposure was performed at 1,000 mJ / cm ² on both sides without using a photomask by the above-described method. Next, curing was performed by the method described above to prepare a sample. This sample film was cut into 20 cm × 5 cm, and the flame retardancy was evaluated by UL94 VTM test. Samples whose afterflame time of each sample was 10 seconds or less and did not burn to the 12.5 cm mark were evaluated as ◯, and the afterflame time of each sample was burned to the mark of 10 seconds or more or 12.5 cm The sample was evaluated as x.

評価例結果から明らかなように、本発明に係る感光性樹脂組成物は少量の光塩基発生剤の添加で良好なフォトリソグラフィー性を有していることが分った。比較例１では添加した光塩基発生剤が乾燥時にフィルムから飛散した為、充分なフォトリソグラフィー性が得られなかった。比較例２では未分解のＰＢＧがキュアの熱により熱分解物を起こし機械物性が低下した。比較例３では光塩基発生剤より発生する塩基のイミド化触媒としての性能が低い為、充分なフォトリソグラフィー性が得られなかった。また発生する塩基によりキュア後のフィルムが脆く変質した。 <Evaluation example results>

As is clear from the results of the evaluation examples, it was found that the photosensitive resin composition according to the present invention has good photolithography properties with the addition of a small amount of a photobase generator. In Comparative Example 1, since the added photobase generator was scattered from the film during drying, sufficient photolithographic properties could not be obtained. In Comparative Example 2, undecomposed PBG caused a thermal decomposition product due to the heat of curing, and the mechanical properties deteriorated. In Comparative Example 3, the performance as a catalyst for imidization of a base generated from a photobase generator was low, so that sufficient photolithographic properties could not be obtained. Further, the cured base film was brittle and altered by the generated base.

  The present invention is not limited to the embodiment described above, and can be implemented with various modifications. It is not limited to this about the numerical value and component in the said embodiment, It is possible to change suitably and to implement. In addition, various modifications can be made without departing from the scope of the present invention.

  The present invention can be applied to a patterning process using photolithography capable of alkali development.

Claims (15)

A photosensitive resin composition containing a photobase generator (A) and a polyamic acid (B), wherein the photobase generator is a compound containing an acyloxyimino group represented by formula (1). The photosensitive resin composition characterized by the above-mentioned.

(In the formula, X ¹ is an arylene group, and n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.) The photobase generator is a compound containing an acyloxyimino group represented by the formula (1), and the compound is represented by the formula (2) or the formula (3). The photosensitive resin composition as described.

(In the formula, n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.)

(In the formula, n represents an integer of 0 to 3. R ¹ is an aromatic group or an alkyl group having 2 or more carbon atoms.) The photosensitive resin composition according to claim 1, wherein the polyamic acid is a polyamic acid obtained using a diamine represented by the formula (4).

(In the formula, R ^a is ^a divalent organic group having 1 to 50 carbon atoms. K represents a number of 1 to 50.) The photosensitive resin composition according to claim 3, wherein the polyamic acid is a polyamic acid obtained by using an acid dianhydride represented by the formula (5).

(In the formula, l represents a number of 1 to 20. m represents an integer of 2 to 50.) The photosensitive resin composition according to claim 3 or 4, wherein the polyamic acid is a polyamic acid obtained by using a diamine represented by the formula (6).

(In the formula, Z is a divalent organic group and is selected from the organic groups shown in Formula (7).)

(In the formula, p represents an integer of 3 to 5.)   The photosensitive resin composition according to any one of claims 3 to 5, wherein the polyamic acid is a polyamic acid obtained by using oxydiphthalic dianhydride.   Furthermore, a photosensitizer (C) is contained, The photosensitive resin composition in any one of the Claims 1-6 characterized by the above-mentioned.   Furthermore, a flame retardant (D) is contained, The photosensitive resin composition in any one of the Claims 1-7 characterized by the above-mentioned.   Furthermore, a plasticizer (E) is contained, The photosensitive resin composition in any one of Claims 1-8 characterized by the above-mentioned.   A photosensitive film comprising the photosensitive resin composition according to claim 1.   A laminated film comprising: a carrier film; and the photosensitive film according to claim 10 provided on the carrier film.   The laminated film according to claim 11, further comprising a cover film formed on the photosensitive film.   A circuit board comprising: a substrate having wiring; and a cover lay configured using the photosensitive film according to claim 10 or the laminated film according to claim 11 or 12. .   Using the photosensitive resin composition according to any one of claims 1 to 9, a step of forming a resin composition layer on a substrate having at least wiring, and pattern exposure to the resin composition layer A circuit comprising: a step; a step of developing the resin composition layer after the pattern exposure using an alkaline aqueous solution; and a step of curing the resin composition layer after the development treatment. A method for manufacturing a substrate.   Laminating at least the photosensitive film according to claim 10 or the laminated film according to claim 11 or 12 on a substrate having wiring, and forming a resin composition layer; A step of performing pattern exposure on the resin composition layer, a step of developing the resin composition layer after the pattern exposure using an alkaline aqueous solution, a step of curing the resin composition layer after the development treatment, A method of manufacturing a circuit board, comprising: