JP4488875B2 - Photosensitive resin composition and photosensitive resin composition layer-containing laminate - Google Patents

Description

  The present invention relates to a photosensitive resin composition, a composition layer-containing laminate, and further, a printed wiring board, a lead frame, a semiconductor rewiring and the like using the photosensitive resin composition and the composition layer-containing laminate. The present invention relates to a method for manufacturing bumps and the like.

In the production of printed wiring boards and the like, a photosensitive resin layer laminate using a photosensitive resin composition is generally used. As a method for producing the photosensitive resin laminate, for example, first, a photosensitive resin composition is applied on a support such as light-transmitting polyester and dried, and then polyethylene or the like is applied on the dried photosensitive resin laminate. The protective film is laminated. As a method of using the photosensitive resin laminate in forming a circuit, first, after removing the protective film, the photosensitive resin composition layer is thermocompression bonded to the surface of the substrate on which a desired circuit pattern is to be formed, A method of forming an image of a cured resist pattern by irradiating (exposure) actinic rays through a mask, then spraying an alkaline aqueous solution or an organic solvent to dissolve and remove unexposed portions, washing with water, and drying. is there.
The process of dissolving and removing the unexposed area is called a development process, and the process for forming a post-development circuit is roughly divided into two methods. The first method is to remove the cured resist pattern after etching the copper surface not covered with the cured resist pattern, and is called an etching method. The second method is to remove the cured resist pattern and etch the exposed copper surface after plating the copper surface with copper or the like, and is called a plating method.

As a photopolymerization initiator used in a photosensitive resin composition, it has been known for a long time to use hexaarylbiimidazole compounds (for example, see Patent Document 1). Among these compounds, 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetrakisphenylbiimidazole [Cl wherein the chloro group is substituted at the ortho position of the phenyl group at the 2-position of imidazole -HABI] is considered preferable because it is excellent in thermal stability.
However, when the photosensitive resin composition using the above hexaarylbiimidazole compounds is used, a large amount of sludge is generated in the developer due to poor dispersibility in the alkali developer, and the developer nozzle is clogged. In addition, contamination of the developing tank and adhesion of dirt to the substrate to be developed have become problems.
Therefore, a method for introducing a specific substituent into the aryl group of the hexaarylbiimidazole compound (Patent Documents 2, 3, and 4) has been proposed. However, there are problems such as a decrease in adhesion.
Further, a hexaarylimidazole compound in which a methoxy group and a chloro group are introduced into an aryl group has also been proposed (Patent Document 5), but sufficient improvement in terms of developer contamination was not observed.

Japanese Examined Patent Publication No. 45-037377 US Pat. No. 6,180,319 (corresponding to JP 2002-507004 A) JP 2001-222104 A JP 2001-222106 A JP 2002-082434 A

An object of the present invention is to provide a photosensitive resin composition having high resolution, high adhesion, and good development aggregation, and a method for producing a photosensitive resin laminate and a circuit pattern using the composition. To do.

（式中、Ｘ₁は酸素、窒素、硫黄のいずれか１つまたは複数を含むヘテロ単環基であり、Ｙ₁およびＹ₂は、それぞれ独立に無置換または置換されたアリール基である。） As a result of intensive studies to solve the above problems, the present inventors have found a photosensitive resin composition that solves the above problems by including an arylbiimidazole compound having a heterocycle as a photopolymerization initiator, It came to make this invention.
That is, the present invention is as follows.
(1) (a) 30 to 70% by mass of a polymer having a carboxylic acid, an acid equivalent of 100 to 600, and a weight average molecular weight of 20,000 to 500,000, and (b) at least one ethylenically unsaturated bond. 20 to 70% by mass of a photopolymerizable monomer and (c) 0.1 to 20% by mass of a photopolymerization initiator, and (c) as a photopolymerization initiator, the following general formulas (I) to (III) A photosensitive resin composition comprising a photopolymerization initiator having at least one structure selected from the group consisting of:

(Wherein X ₁ is a heteromonocyclic group containing any one or more of oxygen, nitrogen and sulfur, and Y ₁ and Y ₂ are each independently an unsubstituted or substituted aryl group.)

（式中、Ｘ₂は酸素、窒素、硫黄のいずれか１つまたは複数を含むヘテロ単環基であり、Ｙ₃〜Ｙ₇は、それぞれ独立に無置換または置換されたアリール基である。）

（式中、Ｘ₃、Ｘ₄はそれぞれ独立に酸素、窒素、硫黄のいずれか１つまたは複数を含むヘテロ単環基であり、Ｙ₈〜Ｙ₁₁は、それぞれ独立に無置換または置換されたアリール基である。）

(Wherein X ₂ is a heteromonocyclic group containing any one or more of oxygen, nitrogen and sulfur, and Y _{3 to} Y ₇ are each independently an unsubstituted or substituted aryl group.)

(Wherein X ₃ and X ₄ are each independently a heteromonocyclic group containing one or more of oxygen, nitrogen and sulfur, and Y _{8 to} Y ₁₁ are each independently unsubstituted or substituted. An aryl group.)

(2) As a photopolymerization initiator, in the general formulas (I) to (III), each of X _{1 to} X ₄ is independently selected from the group consisting of a 2-pyridyl group, a 3-pyridyl group, and a 4-pyridyl group. In the above (1), each of Y _{1 to} Y ₁₁ is independently a group selected from the group consisting of a phenyl group, a 2-chlorophenyl group and a 3,4-dimethoxyphenyl group. The photosensitive resin composition as described.
(3) A photosensitive resin composition in which the photosensitive resin composition described in the above (1) or (2) is laminated on a support, and a protective film is further laminated on the surface of the photosensitive resin composition opposite to the support. Resin laminate.
(4) The photosensitive resin laminate according to the above (3) is laminated with the protective resin film peeled off on the circuit forming substrate, and the photosensitive resin composition layer is adhered to the substrate. A method for producing a circuit pattern, characterized in that a cured resist pattern is formed by imagewise irradiation, photoirradiation of an irradiated part, and removal of an unirradiated part by development, followed by etching or plating.

  The photosensitive resin composition according to the present invention can achieve both high resolution, high adhesion, and good development aggregation. By using the photosensitive resin composition of the present invention, it is possible to form a wiring pattern that is extremely effective for printed wiring boards, lead frames, semiconductor rewiring, and bump manufacturing.

The present invention will be specifically described below.
(A) As a polymer which has carboxylic acid of a component, it is preferable that an acid equivalent is the range of 100-600, More preferably, it is 200-400. Here, the acid equivalent means the weight of the polymer having 1 equivalent of carboxylic acid therein. The acid equivalent is measured by potentiometric titration with 0.1N sodium hydroxide. The acid equivalent is preferably 100 or more from the viewpoint of compatibility with the coating solvent or the monomer, and preferably 600 or less from the viewpoint of peelability.
The weight average molecular weight of the polymer is preferably 20,000 to 500,000, more preferably 20,000 to 200,000. The molecular weight is measured by gel permeation chromatography (GPC) using a standard polystyrene calibration curve. 500,000 or less is preferable from the viewpoint of developability, and 20,000 or more is preferable from the viewpoint of thickness uniformity when forming the photosensitive resin layer.
Examples of the polymer include a monomer having a carboxylic acid as the first monomer and having one polymerizable unsaturated group such as a carbon-carbon double bond in the molecule. Examples of the first monomer include (meth) acrylic acid, fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic acid half ester, and the like.
The polymer is a non-acidic monomer having a polymerizable unsaturated group such as a carbon-carbon double bond in the molecule as the second monomer, and in the developability, etching and plating steps of the photosensitive resin layer. Monomers having various properties such as resistance to heat and flexibility of the cured film. Examples of the second monomer include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, (meth ) Alkyl (meth) acrylates such as 2-hydroxyethyl acrylate, benzyl (meth) acrylate, vinyl alcohol esters such as vinyl acetate, styrene and polymerizable styrene derivatives, and (meth) acrylonitrile. It is done. Of these, methyl methacrylate and styrene are preferred.
The polymer can be used alone or in combination of two or more.

(A) The polymer of a component is the range whose (a) component is 30-70 mass% with respect to 100 mass% of total amounts of the photosensitive resin composition, Preferably it is 40-60 mass%. 30 mass% or more is preferable from a cold flow viewpoint, and 70 mass% or less is preferable from a brittle viewpoint of the photosensitive resin layer.
A polymer is obtained by adding an appropriate amount of a radical polymerization initiator such as benzoyl peroxide or azobisisobutyronitrile to a solution obtained by diluting a mixture of monomers with a solvent such as acetone, methyl ethyl ketone, isopropanol, or ethanol, It is preferable to synthesize by heating and stirring. In some cases, a part of the mixture is synthesized while being dropped into the reaction solution. In addition, a solvent may be further added after completion of the reaction to prepare a desired concentration. In addition to solution polymerization, it can also be synthesized by bulk polymerization, suspension polymerization and emulsion polymerization.
The photopolymerizable monomer having at least one polymerizable ethylenically unsaturated group in the molecule of component (b) is preferably in the range of 20 to 70% by mass with respect to 100% by mass of the total amount of the photosensitive resin composition. More preferably, it is 30-60 mass%. 20 mass% or more is preferable from a viewpoint of a sensitivity and adhesiveness, and 70 mass% or less is preferable from a cold flow property viewpoint.

  Examples of such photopolymerizable monomers include 1,6-hexanediol di (meth) acrylate, 1,4-cyclohexanediol di (meth) acrylate, polypropylene glycol di (meth) acrylate, and polyethylene glycol di (meth). Acrylate, polyoxyethylene polyoxypropylene glycol di (meth) acrylate, polyoxyalkylene glycol di (meth) acrylate such as bis (triethyleneoxy (meth) acrylate) dodecapropylene glycol, 2-di (p-hydroxyphenyl) propanedi (Meth) acrylate, glycerol tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, polyoxypropyltrimethylolpropane tri (meth) acrylate, polyoxye Lutrimethylolpropane tri (meth) acrylate, glycerol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, trimethylolpropane triglycidyl ether tri (meth) acrylate, bisphenol A diglycidyl Ether di (meth) acrylate, 2,2-bis {(4- (meth) acryloxypolyethoxy) phenyl} propane, octylphenoxypolyethoxy (meth) acrylate, nonylphenoxypolyethoxy (meth) acrylate, nonylphenoxypolyethoxy Polypropyloxy (meth) acrylate, ethyleneoxy modified tri (meth) acrylate of isocyanuric acid, ethyleneoxy modified di (meth) of isocyanuric acid Acrylates, polyfunctional (meth) acrylate containing urethane groups, beta-hydroxypropyl-beta '- (Akuriroirukishi) propyl phthalate, phenoxy polyethylene glycol acrylate. Moreover, the urethanation reaction material of polyvalent isocyanate compounds, such as hexamethylene diisocyanate and tolylene diisocyanate, and hydroxyacrylate compounds, such as 2-hydroxypropyl (meth) acrylate, etc. are mentioned.

（式中、Ｘ₁は酸素、窒素、硫黄のいずれか１つまたは複数を含むヘテロ単環基であり、Ｙ₁およびＹ₂は、それぞれ独立に無置換または置換されたアリール基である。）

（式中、Ｘ₂は酸素、窒素、硫黄のいずれか１つまたは複数を含むヘテロ単環基であり、Ｙ₃〜Ｙ₇は、それぞれ独立に無置換または置換されたアリール基である。） (C) As a photoinitiator of a component, the photoinitiator which has a structure chosen from the group which consists of the following general formula (I)-(III) is included as an essential component.

(Wherein X ₁ is a heteromonocyclic group containing any one or more of oxygen, nitrogen and sulfur, and Y ₁ and Y ₂ are each independently an unsubstituted or substituted aryl group.)

(Wherein X ₂ is a heteromonocyclic group containing any one or more of oxygen, nitrogen and sulfur, and Y _{3 to} Y ₇ are each independently an unsubstituted or substituted aryl group.)

（式中、Ｘ₃、Ｘ₄は酸素、窒素、硫黄のいずれか１つまたは複数を含むヘテロ単環基であり、Ｙ₈〜Ｙ₁₁は、それぞれ独立に無置換または置換されたアリール基である。）
Ｘ₁〜Ｘ₄に該当するヘテロ単環基としては、フラン環、ピラン環、ピロール環、イミダゾール環、ピラゾール環、ピリジン環、ピラジン環、ピリミジン環、ピリダジン環、チオフェン環、イソチアゾール環、イソオキサゾール環、等が挙げられる。特にピリジン環が好ましい。
Ｙ₁〜Ｙ₁₁において選択されるアリール基としては、フェニル基、ナフチル基等が挙げられ、置換基としては、ハロゲン基、アルキル基、アルコキシル基、ヒドロキシル基、ジアルキルアミノ基、カルボキシル基、カルボキシルエステル基、カルボキシルアミド基、等が挙げられる。特にアリール基として、フェニル基が好ましい。また、アリール基の置換基としては、無置換、ハロゲン置換またはメトキシ置換が特に好ましい。さらに感度の観点からＹ₁ 〜Ｙ₄ のうちの１つないし複数がメトキシ基で置換されたアリール基であることが好ましい。

Wherein X ₃ and X ₄ are heteromonocyclic groups containing one or more of oxygen, nitrogen and sulfur, and Y _{8 to} Y ₁₁ are each independently an unsubstituted or substituted aryl group. is there.)
Heterocyclic groups corresponding to X _{1 to} X ₄ include furan ring, pyran ring, pyrrole ring, imidazole ring, pyrazole ring, pyridine ring, pyrazine ring, pyrimidine ring, pyridazine ring, thiophene ring, isothiazole ring, And an oxazole ring. A pyridine ring is particularly preferable.
Examples of the aryl group selected from Y _{1 to} Y ₁₁ include a phenyl group and a naphthyl group, and examples of the substituent include a halogen group, an alkyl group, an alkoxyl group, a hydroxyl group, a dialkylamino group, a carboxyl group, and a carboxyl ester. Group, carboxylamide group, and the like. A phenyl group is particularly preferable as the aryl group. Further, as the substituent of the aryl group, unsubstituted, halogen-substituted or methoxy-substituted is particularly preferable. Further, from the viewpoint of sensitivity, one or more of Y ₁ to Y ₄ is preferably an aryl group substituted with a methoxy group.

The compounds having the structures of the general formulas (I) to (III) can be synthesized by a method similar to the synthesis of generally well-known biimidazole initiators. The synthesis method is described in, for example, JP-A-56-35134 and US Pat. No. 4,252,878. Specifically, a benzyl compound and a benzaldehyde compound corresponding to a desired structure are contained in an acetic acid solvent. It is described that an imidazole monomer is synthesized using ammonium acetate as a catalyst, and that imidazole monomer is further oxidatively coupled (dimerized) by adding potassium ferricyanide in a strong alkaline solvent.
For example, in the case of the synthesis of 2,2′-bis (2-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, an imidazole monomer is made from 2-pyridylaldehyde and benzyl, Is synthesized by dimerization.
Further, for example, in the case of synthesis of 2-phenyl-2 ′-(2-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, an imidazole monomer synthesized from 2-pyridylaldehyde and benzyl And dimerization using an imidazole monomer synthesized from benzaldehyde and benzyl.

  Examples of the biimidazole compound represented by the general formula (I) include 2,2′-bis (2-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis ( 3-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (4-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2 '-Bis (2-furyl) -4,4', 5,5'-tetraphenylbiimidazole, 2,2'-bis (3-furyl) -4,4 ', 5,5'-tetraphenylbiimidazole 2,2′-bis (2-thienyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (3-thienyl) -4,4 ′, 5,5′- Tetraphenylbiimidazole, 2,2'-bis (2-pyrazinyl) -4,4 , 5,5'-tetraphenylbiimidazole, 2,2'-bis (2-pyrimidinyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (4-pyrimidinyl)- 4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (5-pyrimidinyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (2 -Pyridyl) -4,4'-bis (3,4-dimethoxyphenyl) -5,5'-diphenylbiimidazole, 2,2'-bis (3-pyridyl) -4,4'-bis (3,4) -Dimethoxyphenyl) -5,5'-diphenylbiimidazole, 2,2'-bis (4-pyridyl) -4,4'-bis (3,4-dimethoxyphenyl) -5,5 ''-diphenylbiimidazole , 2,2′-bis (2- Lysyl) -4,4′-bis (3,4-dimethoxyphenyl) -5,5′-bis (2-chlorophenyl) biimidazole, 2,2′-bis (3-pyridyl) -4,4′-bis (3,4-dimethoxyphenyl) -5,5′-bis (2-chlorophenyl) biimidazole, 2,2′-bis (4-pyridyl) -4,4′-bis (3,4-dimethoxyphenyl)- 5,5′-bis (2-chlorophenyl) biimidazole, and the like. In particular, 2,2′-bis (3-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2,2′-bis (3-pyridyl) -4,4′-bis (3, 4-Dimethoxyphenyl) -5,5′-bis (2-chlorophenyl) biimidazole is preferred.

Furthermore, as a compound represented by general formula (II), 2-phenyl-2 '-(2-pyridyl) -4,4', 5,5'-tetraphenylbiimidazole, 2-phenyl-2'- (3-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2-phenyl-2 ′-(4-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2 -Phenyl-2 '-(2-furyl) -4,4', 5,5'-tetraphenylbiimidazole, 2-phenyl-2 '-(3-furyl) -4,4', 5,5'- Tetraphenylbiimidazole, 2-phenyl-2 ′-(2-thienyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2-phenyl-2 ′-(3-thienyl) -4,4 ′ , 5,5'-tetraphenylbiimidazole, 2-phenyl-2 '-(2-pyrazinyl ) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2-phenyl-2 ′-(2-pyrimidinyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2-phenyl-2 '-(4-pyrimidinyl) -4,4', 5,5'-tetraphenylbiimidazole, 2-phenyl-2 '-(5-pyrimidinyl) -4,4', 5,5'-tetraphenylbiimidazole 2- (2-chlorophenyl) -2 ′-(2-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (2-chlorophenyl) -2 ′-(3-pyridyl)- 4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (2-chlorophenyl) -2 ′-(4-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- ( 3-chlorophenyl) -2 '-(2-pyridyl) -4,4' , 5,5′-tetraphenylbiimidazole, 2- (3-chlorophenyl) -2 ′-(3-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (3-chlorophenyl) -2 '-(4-pyridyl) -4,4', 5,5'-tetraphenylbiimidazole, 2- (4-chlorophenyl) -2 '-(2-pyridyl) -4,4', 5,5 '-Tetraphenylbiimidazole, 2- (4-chlorophenyl) -2'-(3-pyridyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2- (4-chlorophenyl) -2'- (4-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (2-chlorophenyl) -2 ′-(2-furyl) -4,4 ′, 5,5′-tetraphenyl Biimidazole, 2- (2-chlorophenyl) -2 '-(3- Ril) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (2-chlorophenyl) -2 ′-(2-thienyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (2-Chlorophenyl) -2 ′-(3-thienyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (2-chlorophenyl) -2 ′-(2-pyrazinyl) -4 , 4 ′, 5,5′-tetraphenylbiimidazole, 2- (2-chlorophenyl) -2 ′-(2-pyrimidinyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (2 -Chlorophenyl) -2 '-(4-pyrimidinyl) -4,4', 5,5'-tetraphenylbiimidazole, 2- (2-chlorophenyl) -2 '-(5-pyrimidinyl) -4,4', 5,5′-tetraphenylbiimidazole, 2- (2 Chlorophenyl) -2 '-(2-pyridyl) -4'-(3,4-dimethoxyphenyl) -5 '-(2-chlorophenyl) -4,5, -diphenylbiimidazole, 2- (2-chlorophenyl)- 2 '-(3-pyridyl) -4'-(3,4-dimethoxyphenyl) -5 '-(2-chlorophenyl) -4,5, -diphenylbiimidazole, 2- (2-chlorophenyl) -2'- (4-pyridyl) -4 ′-(3,4-dimethoxyphenyl) -5 ′-(2-chlorophenyl) -4,5, -diphenylbiimidazole,
2- (2-pyridyl) -2 ′-(2-chlorophenyl) -4 ′-(3,4-dimethoxyphenyl) -5 ′-(2-chlorophenyl) -4,5, -diphenylbiimidazole, 2- ( 3-pyridyl) -2 ′-(2-chlorophenyl) -4 ′-(3,4-dimethoxyphenyl) -5 ″-(2-chlorophenyl) -4,5, -diphenylbiimidazole, 2- (4- Pyridyl) -2 '-(2-chlorophenyl) -4'-(3,4-dimethoxyphenyl) -5 '-(2-chlorophenyl) -4,5, -diphenylbiimidazole, and the like.

Furthermore, the compound represented by the general formula (III) includes 2,2′-bis (2-pyridyl) -4- (3,4-dimethoxyphenyl) -5- (2-chlorophenyl) -4 ′, 5. '-Diphenylbiimidazole, 2,2'-bis (3-pyridyl) -4- (3,4-dimethoxyphenyl) -5- (2-chlorophenyl) -4', 5'-diphenylbiimidazole, 2,2 '-Bis (4-pyridyl) -4- (3,4-dimethoxyphenyl) -5- (2-chlorophenyl) -4', 5'-diphenylbiimidazole, 2,2'-bis (2-furyl)- 4- (3,4-dimethoxyphenyl) -5- (2-chlorophenyl) -4 ′, 5′-diphenylbiimidazole, 2,2′-bis (3-furyl) -4- (3,4-dimethoxyphenyl) ) -5- (2-chlorophenyl) -4 ', '-Diphenylbiimidazole, 2,2'-bis (2-thienyl) -4- (3,4-dimethoxyphenyl) -5- (2-chlorophenyl) -4', 5'-diphenylbiimidazole, 2,2 '-Bis (3-thienyl) -4- (3,4-dimethoxyphenyl) -5- (2-chlorophenyl) -4', 5'-diphenylbiimidazole, 2,2'-bis (2-pyrazinyl)- 4- (3,4-Dimethoxyphenyl) -5- (2-chlorophenyl) -4 ′, 5′-diphenylbiimidazole, 2,2′-bis (2-pyrimidinyl) -4- (3,4-dimethoxyphenyl) ) -5- (2-chlorophenyl) -4 ′, 5′-diphenylbiimidazole, 2,2′-bis (4-pyrimidinyl) -4- (3,4-dimethoxyphenyl) -5- (2-chlorophenyl) -4 ', 5'-di E D biimidazole, 2,2'-bis (5-pyrimidinyl) -4- (3,4-dimethoxyphenyl) -5- (2-chlorophenyl) -4 ', 5'-diphenyl-biimidazole, and the like.
In particular, 2- (2-chlorophenyl) -2 ′-(3-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole, 2- (2-chlorophenyl) -2 ′-(3-pyridyl) -4 '-(3,4-dimethoxyphenyl) -5'-(2-chlorophenyl) -4,5, -diphenylbiimidazole, 2- (3-pyridyl) -2 '-(2-chlorophenyl) -4' -(3,4-Dimethoxyphenyl) -5 '-(2-chlorophenyl) -4,5, -diphenylbiimidazole is preferred.

0.1-20 mass% of a photoinitiator is preferable, More preferably, it is 0.05-10 mass%. From the viewpoint of curability at the bottom of the photosensitive resin layer resulting from the absorptivity of actinic rays, it is preferably 20% by mass or less, and from the viewpoint of sensitivity, it is preferably 0.1% by mass or more.
Furthermore, as a photopolymerization initiator of component (c), it is possible to combine a photopolymerization initiator having any one structure of general formulas (I) to (III) with p-aminophenyl ketone from the viewpoint of sensitivity and adhesiveness. To preferred.
In this case, it is preferable to combine 0.1 to 1% by mass of p-aminophenyl ketone and 0.1 to 10% by mass of a photopolymerization initiator having a structure of general formulas (I) to (III). From the viewpoint of sensitivity, the p-aminophenyl ketone is preferably 0.1% by mass, and from the viewpoint of sensitivity, the photopolymerization initiator having the structure of the general formula (I) is preferably 0.1% by mass or more. The p-aminophenyl ketone is preferably 1% by mass or less from the viewpoint of adhesion, and the photopolymerization initiator having the structure of the general formulas (I) to (III) is preferably 10% by mass or less from the viewpoint of development aggregation.
As the p-aminophenyl ketone, aromatic ketones such as Michler's ketone [4,4′-bis (dimethylamino) benzophenone], 4,4′-bis (diethylamino) benzophenone are preferable.

  As the photopolymerization initiator, a photopolymerization initiator other than p-aminophenyl ketone and a photopolymerization initiator having a structure of general formulas (I) to (III) can be used in combination. Examples of these photopolymerization initiators include 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3-benzanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone. Quinones such as 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone, 2,3-dimethylanthraquinone, 3-chloro-2-methylanthraquinone Benzophenone, benzoin, benzoin ethyl ether, benzoin phenyl ether, benzoin ethers such as methylbenzoin and ethylbenzoin, acridines such as 9-phenylacridine, N-aryl-α-amino acids such as N-phenylglycine, thio Combinations of xanthones and aminobenzoic acid, such as ethylthioxanthone and ethyl dimethylaminobenzoate, 2-chlorothioxanthone and ethyl dimethylaminobenzoate, combinations of isopropylthioxanthone and ethyl dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, etc. Alkylbenzoic acids, 1-phenyl-1,2-propanedione-2-o-benzoin oxime, 1-phenyl-1,2-propanedione-2-o-ethoxycarbonyloxime, and the like.

In addition, to the photosensitive resin composition of the present invention, if necessary, addition of a radical polymerization inhibitor, a plasticizer, a coloring dye, a dye for coloring, etc. for improving thermal stability and storage stability An agent can be added.
Examples of the radical polymerization inhibitor include p-methoxyphenol, hydroquinone, pyrogallol, naphthylamine, cuprous chloride, pentaerythrityltetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate. ] (Manufactured by Ciba Geigy Japan, IRGANOX (registered trademark) 1010), triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate] (manufactured by Ciba Geigy Japan, IRGANOX (registered) Trademark) 245), octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate (manufactured by Ciba Geigy Japan, IRGANOX (registered trademark) 1076), and the like.
Examples of the plasticizer include phthalic acid ester compounds such as diethyl phthalate and diphenyl phthalate, sulfonamide compounds such as p-toluenesulfonamide, petroleum resins, rosin, polyethylene glycol, polypropylene glycol, and ethylene glycol-propylene glycol block copolymers. A polymer etc. are mentioned.
Examples of the coloring dye include tris (4-dimethylaminophenyl) methane {leuco crystal violet}, tris (4-diethylamino-2-methylphenyl) methane [leucomalachite green], and the like.
Examples of the dye for coloring include diamond green (CI Basic Green 1), malachite green (CI Basic Green), and Victoria Pure Blue.

A method for producing a photosensitive resin laminate by sequentially laminating the support (A), the photosensitive resin layer (B), and the protective film (C) can be performed by a conventionally known method. For example, the photosensitive resin composition used for the photosensitive resin layer (B) is mixed with a solvent for dissolving them to form a uniform solution, and first applied onto the support (A) using a bar coater or roll coater. Then, the photosensitive resin layer (B) made of the photosensitive resin composition is laminated on the support (A). Next, a photosensitive resin laminate can be prepared by laminating the protective film (C) on the photosensitive resin layer (B).
The support (A) in the present invention is preferably transparent so as to transmit active light. For example, polyethylene terephthalate film, polyethylene naphthalate film, polyvinyl alcohol film, polyvinyl chloride film, vinyl chloride copolymer film, polyvinylidene chloride film, vinylidene chloride copolymer film, polymethyl methacrylate copolymer film, polystyrene film , Polyacrylonitrile film, styrene copolymer film, polyamide film, or cellulose derivative film.

The thickness of the support (A) is 10 to 30 μm, preferably 12 to 20 μm. From the viewpoint of flexibility and handleability, the thickness of the support (A) is preferably 10 μm or more, and preferably 30 μm or less from the viewpoint of resolution.
The thickness after drying of the photosensitive resin assembly layer (B) of the present invention is 1 to 150 μm, preferably 3 to 50 μm is used. The thickness of the photosensitive resin layer is preferably 1 μm or more from the viewpoint of film-forming coating. From the viewpoint of resolution and adhesion, 150 μm or less is preferable.
The protective film (C) of the present invention preferably has a thickness of 20 to 50 μm, more preferably 22 to 40 μm. The convex portions of the raw material undissolved material generated in the polyethylene film are transferred to the photosensitive resin layer, and the photosensitive resin layer is dented, and this portion becomes an air void. The thickness of the protective layer (C) is 20 μm or more from the viewpoint of suppressing the phenomenon that the plating solution penetrates into the void at the bottom of the resist, thereby causing defects such as circuit breakage, disconnection, short-circuiting, and the yield of the final product is reduced. Is preferred. Further, the thickness of the protective film (C) is preferably 50 μm or less from the economical viewpoint.
Examples of the film used for the protective film (C) of the present invention include polyolefin films such as polyethylene films and polypropylene films, polyester films, and polyester films whose peelability is improved by silicone treatment or alkyd treatment. A polyethylene film is particularly preferable.

Next, an example of a method for producing a printed wiring board using the photosensitive resin laminate of the present invention will be described.
(1) Lamination process: It heat-presses using hot roll laminator on board | substrates, such as a copper clad laminated board and a flexible substrate, peeling off the protective film of the photosensitive resin laminated body.
(2) Exposure step: A photomask having a desired wiring pattern is brought into close contact with the support and exposed using an ultraviolet light source. Alternatively, exposure is performed by projecting a photomask image using a projection lens. When projecting a photomask image, the support may be peeled off and exposed, or the support may be exposed.
(3) Development step: If the support remains, peel off the support and then dissolve or disperse the unexposed portions of the photosensitive resin layer using an alkaline developer to form a cured resist pattern on the substrate. To do.
(4) Circuit forming step: etching a copper surface not covered with the cured resist pattern from above the formed cured resist pattern using an etchant, or copper, solder on the copper surface not covered with the cured resist pattern, Nickel and tin are plated.
(5) Stripping step: The cured resist pattern is removed from the substrate using an alkaline stripping solution.
Examples of the ultraviolet light source used in the exposure process include a high pressure mercury lamp, an ultra high pressure mercury lamp, an ultraviolet fluorescent lamp, a carbon arc lamp, and a xenon lamp. In order to obtain a finer resist pattern, it is preferable to use a parallel light source.
As the alkaline aqueous solution used in the development step, an aqueous solution of sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide or the like is used. Most commonly, a 0.2 to 2 wt% aqueous sodium carbonate solution is used.
In the peeling step, peeling is performed by using an alkaline aqueous solution that is stronger than the alkaline aqueous solution used in the development. For example, an aqueous solution of 1 to 5 wt% sodium hydroxide or potassium hydroxide is used.
Hereinafter, the embodiments of the present invention will be described in more detail by way of examples.

1) Basic evaluation (production of photosensitive resin laminate)
Table 1 shows the compositions of the photosensitive resin compositions used in the examples and comparative examples. In addition, components represented by abbreviations (B-1 to X-2) in Table 1 are shown below.
<Symbol explanation>
B-1: Polymer having a weight ratio composition of methyl methacrylate / styrene / methacrylic acid = 50/25/25, a weight average molecular weight of 50,000, a dispersity of 2.6, and an acid equivalent of 344 (35% solid content) Concentration of methyl ethyl ketone solution)
B-2: Polymer having a weight ratio composition of methyl methacrylate / butyl acrylate / methacrylic acid = 65/10/25, a weight average molecular weight of 220,000, a dispersity of 8.9, and an acid equivalent of 344 (25% solids) (Methyl ethyl ketone solution with partial concentration)
M-1: Polypropylene glycol with an average of 12 moles of propylene oxide added and glycol dimethacrylate with an average of 3 moles of ethylene oxide added to both ends M-2: Hexamethylene diisocyanate and oligopropylene glycol monomethacrylate (Nippon Yushi Co., Ltd.) ) Reactant M-3: (2,2-bis {4- (methacryloxypentaethoxy) phenyl} propane (manufactured by Shin-Nakamura Chemical Co., Ltd., BPE-500; product name)
M-4: 4-nonylphenoxyoctaethylene glycol acrylate (manufactured by Toa Gosei Co., Ltd., M-114; product name)
M-5: 4-nonylphenoxyheptaethylene glycol dipropylene glycol acrylate M-6: trimethylolpropane ethylene oxide 3 mol addition triacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd., A-TMPT-3EO; product name)

I-1: 2,2′-bis (3-pyridyl) -4,4 ′, 5,5′-tetraphenylbiimidazole I-2: 2- (2-chlorophenyl) -2 ′-(3-pyridyl) -4,4 ', 5,5'-tetraphenylbiimidazole 1-3: 2- (3-pyridyl) -2'-(2-chlorophenyl) -4 '-(3,4-dimethoxyphenyl) -5' -(2-chlorophenyl) -4,5-diphenylbiimidazole I-4: 2- (2-chlorophenyl) -2 '-(3-pyridyl) -4'-(3,4-dimethoxyphenyl) -5'- (2-Chlorophenyl) -4,5-diphenylbiimidazole I-5: 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole (Kurokin Kasei Co., Ltd.) (Made by company)
I-6: N, N, N ′, N′-tetraethyl-4,4′-diaminobenzophenone (Hodogaya Chemical Co., Ltd.)
I-7: 2,4-diethylthioxanthone (manufactured by Nippon Kayaku Co., Ltd.)
I-8: ethyl p- (N, N-dimethylamino) benzoate (Hodogaya Chemical Co., Ltd.)
D-1: Malachite green (Hodogaya Chemical Co., Ltd.)
D-2: Leuco Crystal Violet (Hodogaya Chemical Co., Ltd.)
D-3: Tribromomethylphenylsulfone (manufactured by Maruhishi Oil Chemical Co., Ltd.)
X-1: Benzotriazole X-2: Triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate] (manufactured by Ciba Geigy Japan, Inc., IRGANOX (registered trademark)) 245)

Next, a method for producing a photosensitive resin laminate will be described.
The components shown in Table 1 were mixed to prepare a solution of the photosensitive resin composition, and uniformly applied to polyethylene terephthalate film: AT301 (manufactured by Teijin DuPont Films, product name, 16 μm thickness, haze 0.2%). And it dried for 4 minutes in 95 degreeC drying machine, and formed the photosensitive resin layer of thickness 40 micrometers.
Next, a polyethylene film: T1-A742A (manufactured by Tamapoly Co., Ltd., product name, 35 μm thickness, Ra = 0.065 μm) was laminated on the resin layer to obtain a photosensitive resin laminate. (Board surface adjustment)
A copper clad laminate (thickness: 1.6 mm) having a copper foil thickness of 35 μm was subjected to jet scrub polishing (spray pressure: R # 220) using abrasive grains (manufactured by Nippon Carlit Co., Ltd.). 0.2 MPa).
(laminate)
While peeling the polyethylene film of the photosensitive resin laminate on the flattened copper-clad laminate, the photosensitive resin layer was applied to a hot roll laminator (Asahi Kasei Engineering Co., Ltd., A
L-700, a laminator) was used to laminate at a roll temperature of 105 ° C., a roll pressure of 0.35 MPa, and a laminating speed of 1 m / min.
(exposure)
Using an exposure machine (HMW-201KB: manufactured by Oak Manufacturing Co., Ltd.) having an ultrahigh pressure mercury lamp, a PET mask was placed on a polyethylene terephthalate film as a support film, and exposed at 60 mJ / cm ² through the film.
(developing)
The polyethylene terephthalate film was removed, and a 1 wt% sodium carbonate aqueous solution was sprayed at 30 ° C. and a spray pressure of 0.15 MPa for 45 seconds to remove unexposed portions.

2) Resolution Resolution was developed using a resolution mask (stripe, resist line: space portion = 1: 1) and developed. The minimum space formed with an accuracy within ± 20% of the space width between the two resist lines after development was determined. The case where the minimum space was less than 40 μm was evaluated as ◎, the case where it was 40 μm or more and less than 50 μm was evaluated as ◯, and the case where the minimum space was 50 μm or more was determined as ×.
3) Adhesiveness It exposed and developed using the independent line mask (resist line: space part = 1: 100). The smallest independent line that was linearly in contact with the entire line without development of meandering or chipping was obtained. The case where this minimum independent line was less than 30 μm was judged as “◎”, the case where it was 30 μm or more and less than 40 μm, and the case where it was 40 μm or more were judged as “X”.
4) Development aggregation property 6 g of the unexposed photosensitive resin layer was dissolved and dispersed in 200 ml of 1% aqueous sodium carbonate solution. This solution was sprayed continuously for 8 hours (spray pressure = 0.2 MPa) with a developer circulating apparatus equipped with a pump and a spray nozzle, and then the developer was left for 3 days. Thereafter, the mixture was filtered through a 5 μm mesh filter (MILLIPORE, WhiteMite: LSWP), and the dry weight of the development aggregate captured on the filter was measured. When the weight of the developed aggregate was 50 mg or less, it was judged as ◎, when it exceeded 50 mg and 100 mg or less as ○, and when it exceeded 100 mg, it was judged as ×.

5) Sensitivity The substrate for sensitivity evaluation that had passed 15 minutes after the lamination was exposed using a 21-step tablet made by Stöffer whose brightness has changed from transparent to black in 21 steps. After the exposure, the film was developed with a development time twice as long as the minimum development time, and was ranked as follows according to the exposure amount in which the number of step tablet steps where the resist film remained completely was 8.
A: The exposure amount is 60 mJ / cm ² or less.
A: The exposure amount exceeds 60 mJ / cm ² and is 80 mJ / cm ² or less.
△: exposure amount is more than ^{80mJ / cm 2, 100mJ / cm} 2 or less.
X: The exposure amount exceeds 100 mJ / cm ² .
(Examples 1-7, Comparative Examples 1-2)
Using the photosensitive resin composition of Table 1, a photosensitive resin laminate was produced by the method described in 1) Basic Evaluation. Table 1 shows the results of evaluation of 2) resolution, 3) adhesion, 4) development cohesion, and 5) sensitivity using this photosensitive resin laminate.

It can be suitably used for manufacturing printed wiring boards, lead frames, semiconductor rewiring, bump formation, and the like.

Claims (4)

(A) 30 to 70% by mass of a polymer having a carboxylic acid, an acid equivalent of 100 to 600, and a weight average molecular weight of 20,000 to 500,000, and (b) at least one ethylenically unsaturated bond. 20 to 70% by mass of a polymerizable monomer and (c) 0.1 to 20% by mass of a photopolymerization initiator, and (c) as a photopolymerization initiator, the group consisting of the following general formulas (I) to (III) A photosensitive resin composition comprising a photopolymerization initiator having at least one structure selected from:

(Wherein X ₁ is a heteromonocyclic group containing any one or more of oxygen, nitrogen and sulfur, and Y ₁ and Y ₂ are each independently an unsubstituted or substituted aryl group.)

(Wherein X ₂ is a heteromonocyclic group containing any one or more of oxygen, nitrogen and sulfur, and Y _{3 to} Y ₇ are each independently an unsubstituted or substituted aryl group.)

(Wherein X ₃ and X ₄ are each independently a heteromonocyclic group containing one or more of oxygen, nitrogen and sulfur, and Y _{8 to} Y ₁₁ are each independently unsubstituted or substituted. An aryl group.) As a photopolymerization initiator, in the general formulas (I) to (III), each of X _{1 to} X ₄ is independently a group selected from the group consisting of a 2-pyridyl group, a 3-pyridyl group, and a 4-pyridyl group. The photosensitivity according to claim 1, wherein each of Y _{1 to} Y ₁₁ is independently a group selected from the group consisting of a phenyl group, a 2-chlorophenyl group and a 3,4-dimethoxyphenyl group. Resin composition.   The photosensitive resin laminated body which laminated | stacked the photosensitive resin composition of Claim 1 or 2 on the support body, and also laminated | stacked the protective film on the photosensitive resin composition surface on the opposite side to a support body. The photosensitive resin laminate according to claim 3 is laminated so that the photosensitive resin composition layer is in close contact with the substrate after peeling the protective film on the circuit forming substrate, and actinic rays are irradiated imagewise. Then, the irradiated portion is photocured, and the unirradiated portion is removed by development to form a cured resist pattern, followed by etching or plating.