TWI644175B - Photosensitive resin composition, photosensitive element, method for forming photoresist pattern, and method for manufacturing printed circuit board - Google Patents

Abstract

The present invention relates to a photosensitive resin composition, a photosensitive element, a method for forming a photoresist pattern, and a method for producing a printed circuit board; that is, the photosensitive resin composition of the present invention contains: (A) has a lower portion The divalent group binder polymer represented by the general formulae (I) to (IV), (B) a photopolymerizable compound, and (C) a photopolymerization initiator.

[Chemical Formula 3]

[In the formulae (I) to (IV), R ¹ , R ³ , R ⁵ and R ⁶ each independently represent a hydrogen atom or a methyl group, and R ² and R ⁴ each independently represent an alkyl group having 1 to 3 carbon atoms; An alkoxy group having 1 to 3 carbon atoms, an OH group or a halogen atom, and R ⁷ is an alkyl group having 1 to 6 carbon atoms.

Description

Photosensitive resin composition, photosensitive element, method for forming photoresist pattern, and method for manufacturing printed circuit board

The present invention relates to a photosensitive resin composition, a photosensitive element, a method for forming a photoresist pattern, and a method for producing a printed circuit board.

In the field of manufacturing a printed circuit board, a photoresist material used for etching or plating is widely used: a photosensitive resin composition or a layer containing the photosensitive resin composition (hereinafter referred to as "sensitivity" The resin composition layer () is a photosensitive resin composition layer (laminate) which is formed on the support film and has a structure in which a protective film is disposed on the photosensitive resin composition layer.

Conventionally, a printed circuit board is manufactured by using the above-described photosensitive element, for example, by the following procedure. In other words, first, the photosensitive resin composition layer of the photosensitive element is laminated on a circuit-forming substrate such as a copper-clad laminate. At this time, the surface of the support film of the photosensitive resin composition layer (hereinafter referred to as "underside" of the photosensitive resin composition layer) and the surface opposite thereto (hereinafter referred to as a photosensitive resin composition layer) The "upper" is a surface that is in close contact with the circuit that forms the substrate for circuit formation. Therefore, in a state where the protective film is disposed on the upper surface of the photosensitive resin composition layer, the protective film is peeled off while the lamination operation is performed. Further, the lamination is performed by heating and pressure-bonding the photosensitive resin composition layer to the substrate for circuit formation (normal pressure lamination method).

Next, the photosensitive resin composition layer is formed by a mask film or the like. Perform pattern exposure. At this time, the support film is peeled off before or at any time after the exposure. Then, the unexposed portion of the photosensitive resin composition layer is dissolved or dispersed by the developing solution. Next, an etching process or a plating process is performed to form a pattern, and finally, the hardened portion is peeled off and removed.

Here, the etching treatment is a method of removing the hardened photoresist after etching and removing the metal surface of the circuit-forming substrate which is not covered by the cured photoresist formed after development. On the other hand, the plating treatment is performed by performing a plating treatment such as copper and solder on the metal surface of the circuit-forming substrate which is formed by the cured photoresist formed after development, and then removing the hardened photoresist. A method of etching a metal surface covered by the photoresist.

However, as a method of exposing the pattern described above, a method in which a mercury lamp is used as a light source and transmitted through a mask is used. In addition, in recent years, as a new exposure technique, a direct drawing exposure method in which a digital material of a direct drawing pattern of DLP (Digital Light Processing) is directly drawn on a photosensitive resin composition layer is proposed. This direct drawing exposure method is more excellent in alignment accuracy than the exposure method by the reticle, and a fine pattern can be obtained. Therefore, introduction is performed to fabricate a high-density package substrate.

In the exposure of the pattern, in order to increase the production yield, it is necessary to shorten the exposure time as much as possible. In the direct drawing exposure method described above, when a composition of the same degree of sensitivity as that of the photosensitive resin composition used in the conventional exposure method of the reticle is used, a relatively long exposure time is generally required. Therefore, it is necessary to increase the illuminance on the side of the exposure device or to increase the sensitivity of the photosensitive resin composition.

Further, in addition to the above-described sensitivity, the photosensitive resin composition is also excellent in the resolution and the peeling property of the photoresist. If the photosensitive resin composition can provide a photoresist pattern having a good resolution, the short circuit or disconnection between the circuits can be sufficiently reduced. Further, when the photosensitive resin composition can form a photoresist having good peeling characteristics, the formation efficiency of the resist pattern can be improved by shortening the peeling time of the photoresist, and the size of the peeling sheet of the photoresist can be reduced. Reduce the peeling residue of the photoresist and improve the yield of the circuit. In view of such a request, it is proposed to use a photosensitive resin composition having a good sensitivity, a resolution, and a photoresist peeling property, such as a specific binder polymer or a photopolymerization initiator (see, for example, Patent Documents 1 and 2).

Patent Document 1: Japanese Patent Laid-Open No. 2006-234995

Patent Document 2: JP-A-2005-122123

However, the resolution and the peeling resistance of the photosensitive resin composition described in Patent Documents 1 and 2 are not sufficient.

Therefore, the present invention provides a photosensitive resin composition, a photosensitive element, a method for forming a photoresist pattern, and a method for producing a printed circuit board, which have sufficient effects in improving the resolution and the peeling resistance. purpose.

The present inventors have solved the aforementioned problems, and therefore, focusing on stickiness. The composition of the mixture polymer was thoroughly studied. As a result, it has been found that a photosensitive resin composition having a sufficient effect in improving the resolution and the peeling resistance of the photoresist is obtained by using a binder polymer having a specific structure, so that the present invention has been completed.

In other words, the present invention is a photosensitive resin composition containing (A) a divalent group represented by the following general formula (I), a divalent group represented by the following general formula (II), and A divalent group represented by the general formula (III), a divalent group binder polymer represented by the following general formula (IV), (B) a photopolymerizable compound, and (C) a photopolymerization initiator.

Here, in the formula (I), the formula (II), the formula (III) and the formula (IV), R ¹ , R ³ , R ⁵ and R ⁶ each independently represent a hydrogen atom or a methyl group, and R ² and R ⁴ each independently. Each independently represents an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, an OH group or a halogen atom, and R ⁷ is an alkyl group having 1 to 6 carbon atoms, and m or n each independently represents 0. An integer of ~5, when m or n is 2 to 5, a plurality of R ² or R ⁴ may be the same or different from each other.

The present inventors have found that the photosensitive resin composition of the present invention has a sufficient effect on the improvement of the resolution and the photoresist peeling property by using, for example, a binder polymer having a specific structure of the component (A). . Further, the photosensitive resin composition of the present invention has a good sensitivity by containing the components (A) to (C) described above.

Further, the photosensitive resin composition of the present invention (A) binder polymer has a total of 100 parts by mass of the (A) binder polymer, and the divalent group represented by the general formula (I) has 10~. 60 parts by mass, the divalent group represented by the general formula (II) has 10 to 60 parts by mass, and the divalent group represented by the general formula (III) has 20 to 50 parts by mass, which is represented by the general formula (IV). The divalent group has 1 part by mass or more and less than 15 parts by mass. Thereby, the resolution and the photoresist peeling property of the photosensitive resin composition are further improved.

Further, it is preferable that the photosensitive resin composition of the present invention has a (C) photopolymerization initiator having a hexaarylbiimidazole compound. Thereby, the sensitivity of the photosensitive resin composition and the adhesion of the photoresist are improved.

Further, it is preferable that the photosensitive resin composition of the present invention further contains (D) a sensitizing dye. By this, in the state where exposure is performed with light having a peak in a specific wavelength range, it is extremely absorbed in the vicinity of the specific wavelength range, and the sensitivity of the photosensitive resin composition is improved.

Further, it is preferable that the photosensitive resin composition of the present invention further contains an (E) amine compound. Thereby, the sensitivity of the photosensitive resin composition is further improved.

Further, the present invention provides a photosensitive element comprising: a support film; and a photosensitive resin composition layer containing the photosensitive resin composition formed on the support film. When the support film is provided, the photosensitive resin composition layer containing the photosensitive resin composition is provided. Therefore, even in a state in which a photoresist pattern is formed by direct drawing exposure, it is sufficient. The resolution is performed. In addition, it also has a sufficient effect in improving the peeling characteristics of the photoresist.

Further, the present invention provides a method for forming a photoresist pattern, comprising: a lamination step of laminating a photosensitive resin composition layer containing the photosensitive resin composition on a circuit formation substrate; and the photosensitive resin composition layer The exposure step of irradiating the active light to the exposed portion, the step of exposing the exposed portion to light, and the step of forming the substrate for forming the photosensitive resin composition layer, and removing the portion other than the exposed portion of the photosensitive resin composition layer. According to the method for forming a photoresist pattern, a photosensitive resin composition layer containing the photosensitive resin composition is used to form a photoresist pattern, and therefore, even a direct drawing exposure method with a short exposure time is used. It is also possible to form a photoresist pattern with sufficient resolution. In addition, it also improves the peeling characteristics of the photoresist , with sufficient effect.

Moreover, the present invention provides a method of manufacturing a printed circuit board, comprising the steps of forming a conductor pattern by etching or plating a circuit for forming a circuit pattern of a resist pattern by the method for forming a photoresist pattern. According to the method for producing a printed circuit board, the circuit pattern forming substrate having the photoresist pattern can be formed by the above-described photoresist pattern forming method. Therefore, it is possible to manufacture a high-density wiring while sufficiently suppressing it. Broken and shorted printed circuit boards.

According to the present invention, it is possible to provide a photosensitive resin composition, a photosensitive element, a method for forming a photoresist pattern, and a method for producing a printed circuit board, which have sufficient effects in improving resolution and resist release characteristics. .

[Best Embodiment of the Invention]

Hereinafter, the preferred embodiments of the present invention will be described in detail. Further, in the present invention, the term "(meth)acrylic acid means acrylic acid or methacrylic acid, and the term "(meth)acrylate" means acrylate or methacrylate corresponding to the acrylate, so-called (meth) propylene. The fluorenyl group means an acryl fluorenyl group or a methacryl fluorenyl group.

The photosensitive resin composition of the present invention contains (A) a divalent group represented by the above general formula (I) (hereinafter also referred to as "structural unit" And a divalent group represented by the above general formula (II), a divalent group represented by the above general formula (III), a divalent group of a binder polymer represented by the above general formula (IV), and (B) light A polymerizable compound and (C) a photopolymerization initiator.

First, the binder polymer of the component (A) will be described.

(A) The binder polymer is in the above general formula (I), R ¹ represents a hydrogen atom or a methyl group, and R ² represents an alkyl group having 1 to 3 carbon atoms and an alkoxy group having 1 to 3 carbon atoms. An OH group or a halogen atom, and m represents an integer of 0 to 5. A series of polymerizable monomers which are imparted to the structural unit represented by the general formula (I) are styrene or styrene derivatives. In the present invention, the term "styrene derivative" means a hydrogen atom in which styrene is substituted with a substituent (organic group such as an alkyl group or a halogen atom). Examples of the styrene derivative include α-methylstyrene and the like.

Further, in the above general formula (II), R ³ represents a hydrogen atom or a methyl group, and R ⁴ represents an alkyl group having 1 to 3 carbon atoms, an alkoxy group having 1 to 3 carbon atoms, an OH group or a halogen atom. The m system represents an integer of 0 to 5. The series of polymerizable monomers which are imparted to the structural unit represented by the general formula (II) are benzyl (meth) acrylate or benzyl (meth) acrylate. Examples of the benzyl derivative of (meth)acrylic acid include 4-methylbenzyl (meth)acrylate and the like.

Further, in the above general formula (III), R ⁵ represents a hydrogen atom or a methyl group. The (meth)acrylic acid is a series of polymerizable monomers which are imparted to the structural unit represented by the general formula (III).

Further, in the above general formula (IV), R ⁶ each independently represents a hydrogen atom or a methyl group, R ⁷ represents an alkyl group having 1 to 6 carbon atoms, and m or n each independently represents an integer having a carbon number of 0 to 5. . From the viewpoint of shortening the peeling time and improving the resolution, R ⁷ is preferably an alkyl group having 1 to 4 carbon atoms, more preferably an alkyl group having a carbon number of 1 (methyl group). The (meth)acrylic acid alkyl ester is a series of polymerizable monomers which are imparted to the structural unit represented by the general formula (IV).

The (meth)acrylic acid alkyl ester series is, for example, a compound represented by the following general formula (V).

CH ₂ =C(R ⁸ )-COOR ⁹ (V)

Here, in the above general formula (V), R ⁸ represents a hydrogen atom or a methyl group, and R ⁹ represents an alkyl group having 1 to 6 carbon atoms. Further, examples of the alkyl group having 1 to 6 carbon atoms represented by R ⁹ include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, and a structural anisotropy thereof. Examples of the polymerizable monomer represented by the above general formula (V) include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, and (meth)acrylate. A base ester, pentyl (meth) acrylate, hexyl (meth) acrylate or the like. These polymerizable single systems are used singly or in combination of two or more.

In the binder polymer which is the component (A), the content ratio of the structural unit represented by the above formula (I) is preferably 10 to 60 parts by mass based on 100 parts by mass of the total amount of the component (A). More preferably, it is 15 to 55 parts by mass, even more preferably 20 to 50 parts by mass, particularly preferably 20 to 40 parts by mass. It is possible to make the feeling of containing the photosensitive resin composition The optical resin composition layer was excellent in adhesion to the circuit-forming substrate and photoresist peeling characteristics.

In addition, the content ratio of the structural unit represented by the above formula (II) is preferably 10 to 60 parts by mass, more preferably 15 to 55 parts by mass, even more preferably 100 parts by mass based on the total amount of the component (A). It is preferably 20 to 50 parts by mass, particularly preferably 25 to 45 parts by mass. Thus, the photosensitive resin composition layer containing the photosensitive resin composition can be excellent in adhesion to the circuit-forming substrate and the photoresist peeling property.

In addition, the content ratio of the structural unit represented by the above formula (III) is preferably 10 to 60 parts by mass, more preferably 15 to 50 parts by mass, even more preferably 100 parts by mass based on the total amount of the component (A). It is preferably 20 to 40 parts by mass, particularly preferably 25 to 35 parts by mass. Thereby, the photoresist peeling property and the developing property can be made good.

In addition, the content ratio of the structural unit represented by the above formula (IV) is preferably 1 part by mass or more and less than 15 parts by mass, more preferably 2 to 13 parts, per 100 parts by mass of the total amount of the component (A). The mass fraction is even preferably 4 to 12 parts by mass, particularly preferably 5 to 10 parts by mass. Thus, the photosensitive resin composition layer containing the photosensitive resin composition can be excellent in adhesion to the circuit-forming substrate and the photoresist peeling property.

Further, in the binder polymer which is the component (A), the content ratio of the structural unit represented by the above general formula (I) and the structural unit represented by the above general formula (II) is less than 10 parts by mass, respectively. There is a tendency that the resolution is deteriorated. When the amount exceeds 60 parts by mass, the peeling sheet becomes large and the peeling time tends to increase. In addition, the aforementioned general formula (III) When the content ratio of the structural unit is less than 10 parts by mass, the alkali solubility is deteriorated, and the peeling sheet becomes large, and the peeling time tends to increase. When the content exceeds 60 parts by mass, the tendency to lower the resolution occurs. . In addition, when the content ratio of the structural unit represented by the above formula (IV) is less than 1 part by mass, the peeling property tends to decrease, and when it is 15 parts by mass or more, the resolution tends to decrease.

In the state in which the photosensitive resin composition is prepared by using the binder polymer, one type of binder polymer may be used alone, or two or more types of binder polymers may be arbitrarily combined and used. The binder polymer in a state in which two or more types are used in combination is, for example, a binder polymer composed of two or more different copolymer components (including different repeating units as a constituent component), and different types thereof. Two or more kinds of binder polymers having a weight average molecular weight, and two or more kinds of binder polymers having different degrees of dispersion. Further, a polymer having a multimodal molecular weight distribution described in JP-A-11-327137 can also be used.

(A) The weight average molecular weight (Mw) and number average molecular weight (Mn) of the binder polymer can be determined by gel permeation chromatography (GPC) (by using a standard polystyrene calibration line) Conversion). According to this measurement method, the Mw of the binder polymer is preferably 5,000 to 150,000, more preferably 10,000 to 100,000, particularly preferably 20,000 to 50,000. When the Mw is less than 5,000, there is a tendency to lower the resistance to development liquid, and when it exceeds 150,000, the development time tends to be long.

Further, the dispersion degree (Mw/Mn) of the (A) binder polymer is preferably from 1.0 to 3.0, more preferably from 1.0 to 2.0. When the degree of dispersion exceeds 3.0, there is a tendency to lower the adhesion and the resolution.

Further, in the (A) binder polymer, for example, a styrene resin, an epoxy resin, a guanamine resin, a guanamine epoxy resin, an alkyd resin, a phenol resin or the like may be used. Further, these resins are used singly or in combination of two or more.

The binder polymer of the present invention can be produced, for example, by radical polymerization of a polymerizable monomer by a usual method.

The above (A) binder polymer may contain structural units other than the structural unit represented by the above general formulas (I) to (IV). The above (A) binder polymer is preferably one having only the structural unit represented by the above general formulas (I) to (IV), but may be relative to (A) to the extent that the object of the present invention is not impaired. The total amount of the components is 1 to 10 parts by mass of the structural unit other than this. In this state, examples of the polymerizable monomer which is a structural unit other than the structural unit represented by the above general formulas (I) to (IV) include, for example, heptyl (meth)acrylate and octyl (meth)acrylate. Ester, 2-ethylhexyl (meth) acrylate, decyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, (meth) acrylate Acrylamide, acrylonitrile, vinyl-n-butyl ether, such as alkyl ester, 2-hydroxyethyl ester, 2-hydroxypropyl ester, 3-hydroxypropyl ester, 4-hydroxybutyl ester, diacetone acrylamide Ethyl alcohol esters, tetrahydrofurfuryl (meth)acrylate, dimethylaminoethyl (meth)acrylate, diethylaminoethyl (meth)acrylate, (methyl) Glycidyl acrylate, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, (meth)acrylic acid, α-bromine (Meth)acrylic acid, α-chloro(meth)acrylic acid, β-furyl (meth)acrylic acid, β-styryl (meth)acrylic acid, maleic acid, maleic anhydride, cis-butane Maleic acid monomethyl ester, maleic acid monoethyl ester, maleic acid monoisopropyl ester, maleic acid monoester, fumaric acid, cinnamic acid, α-cyanocinnamic acid, clothing Kang acid, crotonic acid, propiolic acid, and the like. These single systems are used singly or in combination of two or more.

The (A) binder polymer of the present invention is preferably one or more selected from the group consisting of a polymer having a carboxyl group, from the viewpoint of the development of the alkali image. Composition. Such a (A) binder polymer can be produced, for example, by radical polymerization of a polymerizable monomer having a carboxyl group other than (meth)acrylic acid and a polymerizable monomer other than this.

The acid value of the (A) binder polymer is preferably from 80 to 250 mgKOH/g, more preferably from 100 to 220 mgKOH/g, particularly preferably from 150 to 210 mgKOH/g. When the acid value is less than 80 mgKOH/g, the development time tends to be long, and when it exceeds 250 mgKOH/g, there is a tendency to reduce the photo-resistance resistance of the light-curing photoresist. Further, in the state where solvent development is carried out as a developing step, it is preferred to prepare a small amount of a polymerizable monomer having a carboxyl group.

Further, the (A) binder polymer may be provided in a molecule having a photosensitive property group as needed.

The binder amount of the (A) component binder is relative to (A) The total amount of the component and the component (B) is preferably 100 to 70 parts by mass, more preferably 35 to 65 parts by mass, particularly preferably 40 to 60 parts by mass, per 100 parts by mass. When the amount is less than 30 parts by mass, the tendency to obtain a good shape may occur, and when it exceeds 70 parts by mass, there is a tendency that a good sensitivity or resolution is not obtained. The binder polymer which is the component (A) is used singly or in combination of two or more.

Next, the photopolymerizable compound of the component (B) will be described.

Examples of the photopolymerizable compound which is a component (B) include, for example, a compound obtained by reacting a polyhydric alcohol with an α,β-unsaturated carboxylic acid, a bisphenol A-based di(meth)acrylate compound, and a glycidyl-containing compound. The compound obtained by the reaction of α,β-unsaturated carboxylic acid, the ethyl urethane monomer having a (meth) acrylate compound having a urethane bond in the molecule, and the oxidation of nonylphenoxy polyethylene Acrylate (also referred to as "nonylphenoxy polyethylene glycol acrylate"), phthalic acid compound, alkyl (meth)acrylate, and the like. These compounds are used singly or in combination of two or more.

The above-mentioned series of compounds obtained by reacting a polyhydric alcohol with an α,β-unsaturated carboxylic acid include, for example, polyethylene glycol di(meth)acrylate having a vinyl number of 2 to 14, and polypropylene glycol having a propylene number of 2 to 14. (Meth) acrylate, trimethylolpropane di(meth) acrylate, trimethylolpropane tri(meth) acrylate, EO denatured trimethylolpropane tri(meth) acrylate, PO denaturation Trimethylolpropane tri(meth)acrylate, EO, PO modified trimethylolpropane tri(meth)acrylate, tetrahydroxyl Methane tri(meth) acrylate, tetramethylol methane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and the like. These compounds are used singly or in combination of two or more. Here, the "EO" means an ethylene oxide, and the EO-denatured compound means a block structure having an ethylene oxide group. Further, "PO" means propylene oxide, and PO-denatured compound means a block structure having a propylene oxide group.

The aforementioned bisphenol A-based di(meth) acrylate compound series is, for example, 2,2-bis(4-((meth) propylene oxidized polyethoxy) phenyl) propane, 2,2- bis (4-( (Meth)propylene oxidized polypropoxy)phenyl)propane, 2,2-bis(4-((meth)propene oxide polybutoxy)phenyl)propane, 2,2-bis(4-(( Methyl) propylene oxidized polyethoxypolypropoxy)phenyl)propane or the like. As the aforementioned 2,2-bis(4-((meth)acrylo-oxylated polyethoxy)phenyl)propane series, for example, 2,2-bis(4-((meth)propene oxide diethoxy)benzene) Propane, 2,2-bis(4-((meth)propene oxide triethoxy)phenyl)propane, 2,2-bis(4-((meth)propene oxide tetraethoxy)benzene Propane, 2,2-bis(4-((meth)propene oxide pentaethoxy)phenyl)propane, 2,2-bis(4-((meth)propene hexaethoxy)benzene) Propane, 2,2-bis(4-((meth)propene oxide heptaethoxy)phenyl)propane, 2,2-bis(4-((meth)propene oxide octaethoxy)benzene) Base) propane, 2,2-bis(4-((meth)propene oxide pentoxide)phenyl)propane, 2,2-bis(4-((meth)propene oxide decethoxy)benzene Propane, 2,2-bis(4-((meth)propene oxide eleven ethoxy)phenyl)propane, 2,2-bis(4-((methyl)propyl) Oxidized dodecaethoxy)phenyl)propane, 2,2-bis(4-((meth)propene oxide tridecethoxy)phenyl)propane, 2,2-bis(4-((A) Propylene oxide hexadecyloxy)phenyl)propane, 2,2-bis(4-((meth)propene oxide fifteen ethoxy)phenyl)propane, 2,2-bis(4-( (Meth)propene oxidizes hexadecyloxy)phenyl)propane or the like.

2,2-bis(4-(methacryl oxypentaethoxy)phenyl)propane is commercially available as BPE-500 (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name) or FA-321M ( Hitachi Chemical Co., Ltd., trade name, 2,2-bis(4-(methacrylic acid pentadecyloxy)phenyl)propane is commercially available as BPE-1300 (Xinzhongcun Chemical Industry) (share) company system, product name). The ethylene oxide group number in one molecule of 2,2-bis(4-((meth)acrylo-oxylated polyethoxy)phenyl)propane is preferably 4 to 20, more preferably 8 to 15. These compounds are used singly or in combination of two or more.

A series of (meth) acrylate compounds having a urethane bond in the molecule, for example, a (meth) propylene monomer having an OH group at the β position and a diisocyanate compound (isocyanate diisocyanate, 2,6-toluene) Addition reaction of isocyanate, 2,4-toluene diisocyanate, 1,6-hexamethylene diisocyanate, etc., tris((meth)propene oxide tetraethylene glycol isocyanate) hexamethylene isocyanate, EO denaturation Ethyl urethane di(meth) acrylate, EO, PO modified urethane di(meth) acrylate, and the like. The EO-modified urethane di(meth) acrylate series is, for example, UA-11 (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name). In addition, as the aforementioned EO, PO modified urethane diester (A) The acrylate series is, for example, UA-13 (manufactured by Shin-Nakamura Chemical Co., Ltd., trade name). These compounds are used singly or in combination of two or more.

Examples of nonylphenoxy polyethylene oxidized acrylates include, for example, nonylphenoxytetraethylene oxidized acrylate, nonylphenoxypentaethylene oxyacrylate, decylphenoxy hexaethylene oxidized acrylate, decyl phenoxy Ethylene oxide acrylate, decyl phenoxy octaethylene oxide acrylate, decyl phenoxy hexaethylene oxide acrylate, decyl phenoxy decylene oxidized acrylate, decyl phenoxy eleven ethylene oxidized acrylic acid ester. The mercaptophenoxy octaethylene oxidized acrylate series is, for example, M-114 (manufactured by Toagosei Co., Ltd., trade name). These compounds are used singly or in combination of two or more.

The foregoing series of phthalic acid compounds are, for example, γ-chloro-β-hydroxypropyl-β′-(meth)acryloyloxyethyl-o-phthalate, β-hydroxyalkyl-β' - (Meth) propylene decyl oxidized ethyl-o-phthalate. These compounds are used singly or in combination of two or more.

Further, from the viewpoint of improving the flexibility of the cured film, it is preferred that the component (B) of the present invention has a polyalkylene group having both an ethylene glycol chain and a propylene glycol chain in the molecule. Alcohol di(meth) acrylate is included. The (meth) acrylate is not particularly limited as long as it has both an ethylene glycol chain and a propylene glycol chain (n-propylene glycol chain or isopropyl glycol chain) as an intramolecular alkylene glycol chain. Further, the (meth) acrylate may further have an n-butanediol chain, an isobutylene glycol chain, an n-pentanediol chain, a hexanediol chain, and a carbon number 4 such as a structural anisotropy. 6 The degree of alkylene glycol chain.

In a state where the amount of the ethylene glycol chain and the propylene glycol chain are plural, a plurality of the ethylene glycol chain and the propylene glycol chain system may be continuously present in blocks, or may be present at random. Further, in the aforementioned isopropyl glycol chain, the propyl group 2 carbon may be bonded to the oxygen atom, and the first stage carbon may be bonded to the oxygen atom.

A series of polyalkylene glycol di(meth)acrylates having at least one polymerizable ethylenically unsaturated bond in these (B) components and having both an ethylene glycol chain and a propylene glycol chain in the molecule, for example The following general formula (VI):

The compound shown, the following general formula (VI):

The compound shown, and the following general formula (VII):

Compounds shown and the like. Here, in the formulae (VI), (VII) and (VIII), R ¹⁰ , R ¹¹ , R ¹² , R ¹³ , R ¹⁴ and R ¹⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 3 carbon atoms. The EO system represents an ethylene glycol chain, the PO system represents a propylene glycol chain, and the m ¹ to m ⁴ and n ¹ to n ⁴ groups each independently represent an integer of 1 to 30. These compounds are used singly or in combination of two or more.

Examples of the alkyl group having 1 to 3 carbon atoms of the above general formulae (VI) to (VIII) include a methyl group, an ethyl group, an n-propyl group, and an i-propyl group.

Further, the total number of repeating numbers of the ethylene glycol chains of the above general formulae (VI) to (VIII) (m ¹ + m ² , m ³ and m ⁴ ) is an integer of 1 to 30, preferably an integer of 1 to 10. More preferably, it is an integer of 4 to 9, and particularly preferably an integer of 5 to 8. When the number of repetitions exceeds 30, there is a tendency that the umbrella reliability and the photoresist shape are deteriorated.

Further, the total number of repeating numbers of the propylene glycol chains of the above general formulae (VI) to (VIII) (n ¹ , n ² + n3 and n ⁴ ) is an integer of 1 to 30, preferably an integer of 5 to 20, more preferably It is an integer from 8 to 16, particularly preferably an integer from 10 to 14. When the number of repetitions exceeds 30, there is a tendency that the resolution is deteriorated and a slurry is generated.

Specific examples of the compound represented by the above general formula (VI) include, for example, a vinyl group having R ¹⁰ = R ¹¹ = methyl group, m ¹ + m ² = 4 (average value), and n ¹ = 12 (average value). Compound (manufactured by Hitachi Chemical Co., Ltd., trade name: FA-023M). Further, as a specific example of the compound represented by the above general formula (VII), for example, R ¹² = R ¹³ = methyl group, m ³ = 6 (average value), and n ² + n ³ = 12 (average value). Vinyl compound (manufactured by Hitachi Chemical Co., Ltd., trade name: FA-024M). Further, as a specific example of the compound represented by the above general formula (VIII), for example, a vinyl compound which is R ¹⁴ = R ¹⁵ = hydrogen atom, m ⁴ = 1 (average value), and n ⁴ = 9 (average value) (New Nakamura Chemical Industry Co., Ltd., sample name: NK ester HEMA-9P). These compounds are used singly or in combination of two or more.

The amount of the photopolymerizable compound as the component (B) is preferably 30 to 70 parts by mass, more preferably 35 to 65 parts by mass based on 100 parts by mass of the total of the components (A) and (B). It is particularly preferably 40 to 60 parts by mass. When the amount is less than 30 parts by mass, there is a tendency that a good sensitivity or resolution is not obtained, and when it exceeds 70 parts by mass, a good shape may not be obtained.

The photopolymerizable compound which is a component (B) is used singly or in combination of two or more. From the viewpoint of improving plating resistance and adhesion, the photopolymerizable compound preferably contains a bisphenol A-based (meth) acrylate compound or has a urethane bond in the molecule. (meth) acrylate compound. Further, from the viewpoint of improving the sensitivity and the resolution, it is preferable to contain a bisphenol A-based (meth) acrylate compound.

In addition, the photopolymerizable compound which is a component (B) preferably contains a polymerizable ethylenic unsaturation in the molecule, from the viewpoint that the size of the resisting release sheet is small and the peeling time is shortened. The photopolymerizable unsaturated compound of the bond is more preferably a photopolymerizable unsaturated compound having a polymerizable ethylenically unsaturated bond in the molecule and two or more polymerizable ethylenically unsaturated bonds in the molecule. The photopolymerizable unsaturated compound is used. In this state, for example, as a series of photopolymerizable unsaturated compounds having a polymerizable ethylenically unsaturated bond in the molecule, phenoxy polyethylene oxide (meth) acrylate, phenoxy group Polyethylene oxide-polypropylene oxide (meth) acrylate, octylphenoxy hexaethylene oxide (meth) acrylate, octyl phenoxy heptaethylene oxide (meth) acrylate, octyl phenoxy VIII Ethylene oxide (meth) acrylate, octylphenoxy hexaethylene oxide (meth) acrylate, octyl phenoxy sesquiethylene oxide (meth) acrylate, nonyl phenoxy polyethylene oxidation (methyl An acrylate, a nonylphenoxy polyethylene oxide-polypropylene oxidized (meth) acrylate, a phthalic acid derivative having a (meth) propylene group, and the like. Further, as a series of photopolymerizable unsaturated compounds having two or more polymerizable ethylenically unsaturated bonds in the molecule, 1,6-hexanediol di(meth)acrylate, 1,4-ring a hexane diol di(meth) acrylate, a polyethylene glycol di(meth) acrylate having a vinyl group of 2 to 14, a polypropylene glycol di(meth) acrylate having a propylene number of 2 to 14, and the foregoing Polyethylene/polypropylene glycol di(meth)acrylate of general formula (VI)-(VIII), bisphenol A-based di(meth)acrylate, and urethane bond in the molecule (methyl) An acrylate, a bis(propylene oxide ethyl) hydroxyethyl isocyanate, a bisphenol A diglycidyl ether di(meth) acrylate, a glycidyl phthalate (meth) acrylate adduct, or the like.

Further, from the viewpoint of being able to improve the resolution, the peeling time, and the exposure margin in a well-balanced manner, it is particularly preferable to combine one kind of photopolymerizable property having a polymerizable ethylenic unsaturated bond in the molecule. A saturated compound and two kinds of photopolymerizable unsaturated compounds having two or more polymerizable ethylenically unsaturated bonds in the molecule are used. In this state, as light having a polymerizable ethylenic unsaturated bond in the molecule As the polymerizable unsaturated compound, for example, phenoxy polyethylene oxidized (meth) acrylate, nonyl phenoxy polyethylene oxidized (meth) acrylate, and (meth) propylene based phthalic acid derivative can be used. Any one of them. Further, as the photopolymerizable unsaturated compound having two or more polymerizable ethylenically unsaturated bonds in the molecule, for example, polyethylene PEG/polypropylene glycol (A) of the above general formulas (VI) to (VIII) may be combined. At least one compound selected from the group consisting of acrylate, EO modified urethane di(meth) acrylate and EO, PO modified urethane di(meth) acrylate and bisphenol A The base acrylate is used.

Next, the photopolymerization initiator of the component (C) will be described.

The series of photopolymerization initiators which are (C) components are, for example, 4,4'-bis(diethylamino)benzophenone, benzophenone, 2-benzyl-2-dimethylamino-1 -(4-morpholinophenyl)-butanone-1,2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-acetone-1 a benzoin ether compound such as an alkyl hydrazine or a benzoin alkyl ether, a benzoin compound such as a benzoin or an alkyl benzoin, or a benzyl dimethyl ketal. Benzyl derivative, 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-bis(methoxyphenyl)imidazole Dimer, 2-(o-fluorophenyl)-4,5-diphenylimidazole dimer, 2-(o-methoxyphenyl)-4,5-diphenylimidazole dimer, 2,4,5-triarylimidazole dimer such as 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer, 9-phenyl acridine, 1,7-double An acridine derivative such as (9,9'-acridinyl)heptane or the like.

Further, in the above 2,4,5-triarylimidazole dimer, the substituent of the aryl group of the two 2,4,5-triarylimidazoles may be given to the same target compound, and may be different. Asymmetric compound. Further, from the viewpoint of adhesion and sensitivity, the photopolymerization initiator is preferably a hexaaryldiimidazole compound which is a 2,4,5-triarylimidazole dimer. These photopolymerization initiators are used singly or in combination of two or more.

In addition, the amount of the photopolymerization initiator to be the component (C) is preferably 0.1 to 10 parts by mass, more preferably 2 to 10 parts by mass based on 100 parts by mass of the total of the components (A) and (B). 6 parts by mass, particularly preferably 3.5 to 5 parts by mass. When the amount is less than 0.1 part by mass, there is a tendency that a good sensitivity or resolution is not easily obtained, and when it exceeds 10 parts by mass, there is a tendency that a photoresist pattern having a good shape as required is not likely to occur. The photopolymerizable compound which is a component (C) is used alone or in combination of two or more.

The photosensitive resin composition of the present invention preferably contains (D) a sensitizing dye and/or an (E) amine compound in addition to the components (A) to (C).

The sensitizing dye system which is the component (D) of the present invention can effectively utilize the absorption wavelength of the active light used for the exposure, and is preferably a compound having a maximum absorption wavelength of 370 to 420 nm. In the present invention, it is possible to sufficiently increase the sensitivity to the exposure light for direct drawing exposure by using such a sensitizing dye. When the maximum absorption wavelength of the sensitizing dye is less than 370 nm, there is a tendency to reduce the sensitivity to directly depicting the light for exposure, and the At 420 nm, even in a yellow light environment, there is a tendency to lower the stability.

Examples of sensitizing dyes include, for example, pyrazolines, anthraquinones, coumarins, xanthones, oxazoles, benzoxazoles, thiazoles, benzothiazoles, triazoles, anthraquinones, Triazines, thiophenes, naphthalene diimine, and the like. From the viewpoint of improving the resolution, the adhesion, and the sensitivity, the sensitizing dye system preferably contains an anthraquinone. In addition, the amount of the sensitizing dye is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, even more preferably 100 parts by mass based on the total of the components (A) and (B). It is 0.1 to 2 parts by mass. When the amount is less than 0.01 parts by mass, there is a tendency that a good sensitivity or resolution is not obtained, and when it exceeds 10 parts by mass, there is a tendency that a photoresist pattern having a good shape as required is not likely to occur. The sensitizing dye which is the component (D) is used singly or in combination of two or more.

The amine-based compound which is the component (E) is not particularly limited as long as it can improve the sensitivity of the photosensitive resin composition and has an amine group in the molecule. Specific examples thereof include bis[4-(dimethylamino)phenyl]methane, bis[4-(diethylamino)phenyl]methane, white crystal violet, and the like. The amount of the amine compound is preferably 0.01 to 10 parts by mass, more preferably 0.05 to 5 parts by mass, particularly preferably 0.1, based on 100 parts by mass of the total of the components (A) and (B). ~2 parts by mass. When the amount is less than 0.01 parts by mass, there is a tendency that a good sensitivity is not obtained. When the amount is more than 10 parts by mass, the component (E) tends to precipitate and become a foreign matter after the film is formed. Become component (E) The amine-based compound is used singly or in combination of two or more.

In the photosensitive resin composition of the present invention, it may be contained in an amount of 0.01 to 20 parts by mass per 100 parts by mass of the total amount of the components (A) and (B), and may have at least one in the molecule. a cationically polymerizable cyclic ether group photopolymerizable compound (such as an oxetane compound), a cationic polymerization initiator, a dye such as malachite green, a photochromic agent such as tribromophenylphosphonium or white crystal violet, or a heat Coloring preventive agent, plasticizer such as p-toluidine, pigment, filler, antifoaming agent, flame retardant, stabilizer, adhesion imparting agent, flattening agent, peeling accelerator, oxidation inhibitor, fragrance , patterning agent, thermal crosslinking agent, and the like. These are used alone or in combination of two or more.

Further, the photosensitive resin composition of the present invention can be dissolved in methanol, ethanol, acetone, methyl ethyl ketone, methyl glycol ethyl ether, ethyl glycol ethyl ether, toluene, N, N-dimethyl A solvent such as carbamide or propylene glycol monomethyl ether or a mixed solvent of these is a solution having a solid content of about 30 to 60% by mass. This solution can be used as a coating liquid for forming a photosensitive resin composition layer of a photosensitive element.

Further, the coating liquid described above may be applied to a surface of a metal plate to form a liquid photoresist, and may be dried, and then coated with a protective film, for example, in addition to a photosensitive resin composition layer for forming a photosensitive element. Use it. Examples of the material of the metal plate include an iron-based alloy such as copper, a copper-based alloy, nickel, chromium, iron, or stainless steel, and preferably a copper, a copper-based alloy, or an iron-based alloy.

Next, the photosensitive element of the present invention will be described. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing a preferred embodiment of a photosensitive element of the present invention. The photosensitive element 1 shown in FIG. 1 is formed of a support film 2, a photosensitive resin composition layer 3 formed on the support film 2 and containing the photosensitive resin composition, and laminated on the photosensitive resin composition layer 3. The protective film 4 is composed of.

As the support film 2, for example, a polymer film having heat resistance and solvent resistance such as polyethylene terephthalate, polypropylene, polyethylene, or polyester can be used. As a series of commercial products, for example, Arufun MA-410, E-200C (in the above product name) manufactured by Oji Paper Co., Ltd., and polypropylene film produced by Shin-Etsu Film Co., Ltd., and PS series produced by Teijin Co., Ltd. A polyethylene terephthalate film or the like (for example, trade name: PS-25) is not limited thereto.

Further, the thickness of the support film 2 is preferably from 1 to 100 μm, more preferably from 5 to 25 μm. When the thickness is less than 1 μm, there is a tendency that the support film is easily broken when the support film is peeled off before development, and when it exceeds 100 μm, the resolution tends to decrease. Further, the support film 2 can be used by laminating both surfaces of the photosensitive resin composition layer, one of which serves as a support for the photosensitive resin composition layer and the other as a protective film for the photosensitive resin composition.

It is preferable that the photosensitive resin composition layer 3 is a solution (coating liquid) in which the photosensitive resin composition is dissolved in the solvent to a solid content of about 30 to 60% by mass, and the solution is applied to the support. The film 2 is dried to form a photosensitive resin composition layer. Coating system can be used For example, it is carried out by a conventional method such as a press roll coater, a comma coater, a gravure coater, an air knife coater, a die coater, a bar coater, or the like. The drying system is carried out at 70 to 150 ° C for 5 to 30 minutes. In addition, the amount of the residual organic solvent in the photosensitive resin composition is preferably 2% by mass or less in view of the prevention of the diffusion of the organic solvent in the subsequent step.

Further, the thickness of the photosensitive resin composition layer 3 varies depending on the use of the photosensitive element, but the thickness after drying is preferably 1 to 100 μm, more preferably 1 to 50 μm. When the thickness is less than 1 μm, the coating tends to be difficult in the industrial application. When the thickness exceeds 100 μm, the effect of the present invention is small, and the tendency of the adhesion and the resolution is lowered.

Further, the transmittance of the photosensitive resin composition layer 3 to light having a wavelength of 405 nm is preferably 5 to 75%, more preferably 7 to 60%, particularly preferably 10 to 40%. When the transmittance is less than 5%, the adhesion tends to be deteriorated, and when it exceeds 75%, the resolution tends to deteriorate. The transmittance can be measured by a UV spectrometer, and the UV spectrometer is a 228A type W beam spectrophotometer (trade name) manufactured by Hitachi, Ltd..

The protective film 4 is preferably an adhesive force between the photosensitive resin composition layer 3 and the protective film 4, and is smaller than the adhesion between the photosensitive resin composition layer 3 and the support film 2, and is preferably a low fisheye shrinkage hole. The film. In addition, when a film is produced by kneading, extrusion, two-axis stretching, or a casting method, a foreign material, an undissolved substance, an oxidative deterioration substance, etc. of a material are taken in. To the case in the film.

As the protective film 4, for example, a polymer film having heat resistance and solvent resistance such as polyethylene terephthalate, polypropylene, polyethylene, or polyester can be used. As a series of commercial products, for example, Arufun MA-410, E-200C (above, trade name) manufactured by Oji Paper Co., Ltd., and polypropylene film produced by Shin-Etsu Film Co., Ltd., and PS series manufactured by Teijin Co., Ltd. A polyethylene terephthalate film or the like (for example, trade name: PS-25) is not limited thereto.

The thickness of the protective film 4 is preferably from 1 to 100 μm, more preferably from 5 to 50 μm, even more preferably from 5 to 30 μm, particularly preferably from 15 to 30 μm. When the thickness is less than 1 μm, there is a tendency that the protective film is broken at the time of lamination, and when it exceeds 100 μm, the tendency for the inexpensiveness to deteriorate is likely to occur.

Further, the photosensitive element 1 of the present invention may further have an intermediate layer of a buffer layer, an adhesive layer, a light absorbing layer, a gas barrier layer, or the like. In addition, the obtained photosensitive element 1 is in the form of a sheet or is wound in a roll shape and stored in a roll shape. Further, at this time, it is preferable to wind the support film 1 so as to be the outermost side. From the viewpoint of end face protection, it is preferable to provide an end face spacer on the end surface of the pressure roller-shaped photosensitive member press roller, and it is preferable to provide moisture prevention from the viewpoint of edge melt resistance. End spacer. Further, it is preferable that the packaging method is packaged in a black sheet having a small moisture permeability. Examples of the winding core include plastics such as a polyethylene resin, a polypropylene resin, a polystyrene resin, a polyvinyl chloride resin, and an ABS resin (acrylonitrile-butadiene-styrene copolymer).

Next, a method of forming the photoresist pattern of the present invention will be described.

The method for forming a photoresist pattern of the present invention comprises at least a lamination step of laminating a photosensitive resin composition layer containing the photosensitive resin composition on a circuit formation substrate, and a predetermined portion of the photosensitive resin composition layer The exposure step of irradiating the active light to the light-cured portion of the exposed portion, and the step of developing the photosensitive resin composition of the portion other than the exposed portion by the circuit-forming substrate. In addition, the "circuit formation substrate" means a substrate including an insulating layer and a conductor layer formed on the insulating layer. Further, the circuit-forming substrate may be formed inside a plurality of layers, or may have a small-diameter through hole.

As a lamination method in which the photosensitive resin composition layer is laminated on the circuit formation substrate in the lamination step, the following method is mentioned. First, the protective film is gradually peeled off from the photosensitive resin composition layer, and the surface portion of the photosensitive resin composition layer which is gradually exposed while being peeled off is adhered to the surface of the circuit for forming the circuit-forming substrate. Next, the photosensitive resin composition layer is heated, and the photosensitive resin composition is laminated on the circuit formation substrate, and lamination is performed. Further, from the viewpoint of improving the adhesion and the traceability, it is preferable that the operation is carried out under reduced pressure. The laminate of the photosensitive element is preferably such that the photosensitive resin composition layer and/or the circuit formation substrate are heated to 70 to 130 ° C, and the pressure contact pressure is preferably 0.1 to 1.0 MPa (1 to 10 kgf/cm ^{2 ).} Degree), however, there are no special restrictions on these conditions. In addition, when the photosensitive resin composition layer is heated to 70 to 130 ° C as described above, it is not necessary to perform preheating treatment on the circuit formation substrate in advance, but in order to further improve the lamination property, Preheating of the substrate for circuit formation is performed.

As a method of forming an exposure portion as an exposure step, a method of irradiating active light onto an image by a negative or positive mask pattern called an original image (mask exposure method) is used. At this time, in a state where the support film existing on the photosensitive resin composition layer transmits the active light, the active light can be irradiated through the support film, and after the support film is light-shielding, after the support film is removed, The photosensitive resin composition layer is irradiated with active light. Further, a method of irradiating the active light in an image form by a direct drawing exposure method such as a laser direct drawing exposure method or a DLP (Digital Light Processing) exposure method may be employed.

As the light source of the active light, a conventional light source such as a carbon arc lamp, a mercury vapor arc lamp, a high pressure mercury lamp, a xenon lamp, an argon laser or the like, a solid laser such as a YAG laser, or a semiconductor laser is used. A light source that emits ultraviolet light, visible light, or the like.

In the method of removing the portion other than the exposed portion as the development step, the support film is removed in the state where the support film is present on the photosensitive resin composition layer, and then removed by wet development, dry development, or the like. A method of developing a portion other than the exposure portion. Thereby, a photoresist pattern is formed.

For example, in the state of wet development, a developing solution corresponding to an alkaline aqueous solution of a photosensitive resin composition, an aqueous developing solution, an organic solvent-based developing liquid, or the like is used, for example, by a dipping method, a struggle method, or a jetting method. Development is carried out by a conventional method such as shaking, rubbing, washing, or the like. In order to improve the resolution, the development method is most suitable for the high pressure injection method. In addition, It is also possible to use two or more types of development methods in combination with the need.

As the developing liquid system, an alkaline aqueous solution which is safe and stable and has good workability is used. As the salt base of the alkaline aqueous solution, for example, an alkali hydroxide such as lithium, sodium or potassium hydroxide, a carbonate of lithium, sodium, potassium or ammonium or a carbonate, potassium phosphate or phosphoric acid such as a bicarbonate is used. An alkali metal pyrophosphate such as sodium or the like, an alkali metal pyrophosphate such as sodium pyrophosphate or potassium pyrophosphate, or borax.

Further, the alkaline aqueous solution used for development is preferably a thin melt of sodium carbonate of 0.1 to 5% by mass, a thin melt of 0.1 to 5% by mass of potassium carbonate, and a hydroxide of 0.1 to 5% by mass. A thin melt of sodium, a thin melt of 0.1 to 5% by mass of sodium tetraborate (borax), and the like. Further, the pH of the alkaline aqueous solution is preferably in the range of 9 to 11, and the temperature is adjusted in accordance with the developability of the photosensitive resin composition layer. Further, a surfactant, an antifoaming agent, a small amount of an organic solvent for promoting development, and the like may be added to the alkaline aqueous solution.

As the water-based developing liquid, a developing liquid composed of water or an aqueous alkali solution and one or more organic solvents is used. Here, as the salt base of the alkaline aqueous solution, in addition to the substances described above, for example, sodium citrate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2- Hydroxymethyl-1,3-propanediol, 1,3-diaminopropanol-2, morpholine, and the like. The pH of the developing solution is preferably as small as possible within a range in which the development of the photoresist can be sufficiently performed, and it is preferably pH 8 to 12, more preferably pH 9 to 10.

As the aforementioned organic solvent series, for example, acetone, ethyl acetate, and Alkoxyethanol having 1 to 4 carbon atoms, ethanol, isopropanol, butanol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether Wait. These are used alone or in combination of two or more. The concentration of the organic solvent is usually preferably from 2 to 90% by mass, and the temperature can be adjusted in accordance with the development property. Further, a small amount of a surfactant, an antifoaming agent, or the like may be added to the aqueous developing solution.

Further, as an organic solvent-based developing liquid series using an organic solvent alone, for example, 1,1,1-trichloroethane, N-methylpyrrolidone, N,N-dimethylformamide, cyclohexanone, and A Isobutyl ketone, γ-butyrolactone, and the like. In order to prevent ignition, these organic solvent-based developing liquids are preferably added in an amount of from 1 to 20% by mass.

As the processing after development, it is possible to further harden and use the photoresist pattern by performing heating at a temperature of about 60 to 250 ° C or exposure of about 0.2 to 10 J/cm ² .

Next, a method of manufacturing a printed circuit board of the present invention will be described.

In the method of manufacturing a printed circuit board of the present invention, a circuit pattern pattern in which a photoresist pattern type substrate is formed is etched or plated by the method for forming a photoresist pattern of the present invention.

The circuit forming substrate is etched or plated to form a photoresist pattern, and is used as a mask for etching or plating a conductor layer or the like of the circuit formation substrate. The etching liquid in the state of being etched is a copper chloride solution, a ferric chloride solution, an alkali etching solution, or a hydrogen peroxide etching solution, and among these, it is preferable that the etching factor is good. Is to use Ferric chloride solution. In addition, as a series of plating methods in the state of plating, for example, copper plating such as copper sulfate plating or copper pyrophosphate plating, and high-uniformity solder plating such as high Throw solder plating, watts. Bath (Watt's bath: nickel sulfate-nickel chloride) plating, nickel plating such as nickel sulfonate, hard gold plating, gold plating such as soft gold plating.

After the end of the etching or plating, the photoresist pattern can be peeled off, for example, by a strong alkaline aqueous solution which is more enhanced in the alkaline aqueous solution used for development. As the strongly alkaline aqueous solution, for example, a 1 to 10% by mass aqueous sodium hydroxide solution, a 1 to 10% by mass aqueous potassium hydroxide solution, or the like is used. Examples of the peeling method series include, for example, a dipping method and a spraying method, and the dipping method and the spraying method may be used alone, or the dipping method or the spraying method may be used in combination. A printed circuit board is obtained by the above.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above.

Example

Hereinafter, the preferred embodiments of the present invention will be described in more detail, but the present invention is not limited to these examples.

(Composition of binder polymer ((A) component)

In a flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel, and a nitrogen introduction tube, 450 g of a methyl ether glycol and toluene having a mass ratio of 3:2 was added, and nitrogen gas was blown thereinto, while stirring and heating were carried out. Up to 80 ° C. On the other hand, the preparation of mixed methacrylic acid as a copolymerization system A solution of 150 g of acid, 25 g of methyl methacrylate, 125 g of benzyl methacrylate, and 200 g of styrene, and 9.0 g of azodiazepine (hereinafter referred to as "solution a"), in a mass ratio of 3 prepared in advance. The mixture of methyl glycol ethyl ether and toluene of 2 was added dropwise to the solution a after 4 hours, and then stirred at 80 ° C while maintaining the temperature for 2 hours. Further, azodiazepine was dissolved in 100 g of a polyethylene glycol diethyl ether and toluene having a mass ratio of 3:2, and 1.2 g of this solution was dropped over 10 minutes. The solution after stirring and dropping was simultaneously heated at 80 ° C for 3 hours, and then heated to 90 ° C over 30 minutes. After keeping at 90 ° C for 2 hours, it was cooled to obtain a binder polymer (A-1).

The nonvolatile component (solid component) of the binder polymer (A-1) was 47.8% by mass, and the weight average molecular weight was 30,000. Further, the weight average molecular weight is measured by gel permeation chromatography, and the weight average molecular weight is guided by conversion using a calibration curve of standard polystyrene. The conditions of GPC are shown below.

Pump: Hitachi L-6000 (Hitachi Manufacturing Co., Ltd., product name)

Column: Gelpack GL-R420+Gelpack GL-R430+Gelpack GL-R440 (3 in total) (in the above, manufactured by Hitachi Chemical Co., Ltd., product name)

Eluent: tetrahydrofuran

Measuring temperature: 40 ° C

Flow rate: 2.05mL/min

Detector: Hitachi L-3300 RI (Hitachi Manufacturing Co., Ltd.) System, product name)

Further, the binder polymers (A-2) to (A-10) were synthesized in the same manner as in the synthesis method of the above-mentioned binder polymer (A-1) to have the composition shown in Table 1 below.

(Modulation of photosensitive resin composition)

The above-mentioned binder polymers (A-1) to (A-10) and the following materials were blended in the mass ratio shown in Table 2, and the photosensitive resin compositions of Examples 1 to 6 and Comparative Examples 1 to 5 were prepared. a solution of the substance.

<Photopolymerizable Compound ((B) Component)>

B-1: 2,2-bis(4-(methacryloylpentylpentaethoxy)phenyl)propane (manufactured by Hitachi Chemical Co., Ltd., trade name: FA-321M)

B-2: a compound represented by the above general formula (VII), wherein R ¹² and R ¹³ are each a methyl group, m ³ = 6 (average value), and n ² + n ³ = 12 (average value) Compound (manufactured by Hitachi Chemical Co., Ltd., trade name: FA-024M)

B-3: 4-n-decylphenoxy octaethylene hydroxy acrylate (manufactured by Toagos Corporation, trade name: M-114)

<Photopolymerization initiator ((C) component)>

C-1: 2,2-bis(2-chlorophenyl)-4,4',5,5'-tetraphenylbisimidazole (manufactured by Hampford Co., Ltd., trade name: BCIM)

<sensitizing pigment ((D) component)>

D-1: 9,10-dibutoxy oxime (made by Kawasaki Chemical Co., Ltd.), trade name: DBA, wavelength showing maximum absorption [λ n] = 368 nm, 388 nm, 410 nm)

<(E) chromogen (amine compound)>

E-1: White crystal violet (manufactured by Yamada Chemical Co., Ltd.)

<dye>

Malachite Green (Osaka Organic Chemical Industry Co., Ltd.)

<solvent>

acetone

Toluene

Methanol

(production of photosensitive element)

A solution of each of the obtained photosensitive resin compositions was applied onto a polyethylene terephthalate film having a thickness of 16 μm which became a support film. Then, it was dried using a hot air convection dryer at 70 ° C and 110 ° C to form a photosensitive resin composition layer having a film thickness of 25 μm after drying. Next, a protective film was laminated on the photosensitive resin composition layer by press-pressing, and the photosensitive elements of Examples 1 to 6 and Comparative Examples 1 to 5 were obtained.

(production of test piece)

Next, using a grinder (manufactured by Sanke Co., Ltd.) having a brush of a considerable amount of 600, a copper-clad laminate laminated with a glass epoxy material laminated on both sides of a copper foil (thickness: 35 mm) (Hitachi Chemical Industry Co., Ltd.) The copper surface of the company's product name: MCL-E-67) was washed with air and then dried to obtain a copper-clad laminate (substrate). Then, after the copper-clad laminate is heated to 80° C., the protective film of each of the photosensitive elements described above is removed on the copper-clad laminate, and the photosensitive resin composition layer is adhered to the copper-clad laminate. On the surface, lamination (lamination) was carried out at 120 ° C under a pressure of 4 kgf / cm ^{2 to} prepare a test piece.

(characteristic evaluation)

<Light sensitivity>

Cooling and laminating the copper-clad laminate of each photosensitive element, at a time point of 23 ° C, in the support film, having a concentration region of 0.00 to 2.00, a concentration step of 0.05, a sheet size of 20 mm × 187 mm, and a size of each step of 3 mm × 12 mm The light tool of the stepped sheet of the 41 segment is closely adhered. A direct-drawing machine DE-1AH (trade name) manufactured by Hitachi Via Mechanics Co., Ltd., which uses a 405 nm blue-violet laser diode as a light source, transmits light tools and supporting films at an exposure amount of 50 mJ/cm ² . Exposure (drawing) to the photosensitive resin composition layer. In addition, the measurement of the illuminance was carried out using an ultraviolet illuminometer (manufactured by USHIO Electric Co., Ltd., trade name: UIT-150) to which a 405 nm corresponding probe was applied.

Next, the support film was peeled off, and a 30% by weight and 1% by mass aqueous sodium carbonate solution was sprayed for 24 seconds to remove the unexposed portion of the photosensitive resin composition layer, and development was carried out. Then, the light sensitivity of the photosensitive resin composition was evaluated by measuring the number of steps of the step-form sheet of the photo-cured film formed on the copper-clad laminate. The evaluation of the light sensitivity is represented by the number of segments of the stepped sheet, and the higher the number of segments of the stepped sheet, the higher the light sensitivity. The results obtained are shown in Table 4.

<resolution>

The resolution is performed by using a light tool having a line width/space width: 6/6 to 30/30 (unit: mm) as a negative film for resolution evaluation. Here, the resolution is a photoresist pattern formed by exposure after exposure to perfectly remove the minimum value (unit: μm) of the spatial width between the line widths of the unexposed portions. Come as an indicator of resolution. The smaller the evaluation coefficient value of the resolution is, the more it becomes a good value. The results obtained are shown in Table 4.

<resist shape>

The photoresist shape after development was observed using a scanning electron microscope (trade name: Hitachi Scanning Electron Microscope S-500A). The photoresist shape is preferably close to a rectangle.

<peelability>

The peelability was evaluated by the following method. First, the photosensitive resin composition layers of the respective examples and comparative examples were formed on a copper-clad laminate, and each photosensitive resin composition layer was exposed and developed to prepare a photocured film having a size of 40 mm × 50 mm. Next, peeling was performed using a 3% sodium hydroxide aqueous solution. The peelability was evaluated as the peeling time by the time when the photohardening film was peeled off from the copper laminate. Further, the size of the release sheet after the end of the peeling was observed by visual observation. Table 3 shows the conditions of the peeling process and the dimensions of the peeling sheet size. The results obtained are shown in Table 4.

<evaluation result>

As shown in Table 4, each of Examples 1 to 6 has a high resolution of 10 μm, moderately shortens the peeling time, and the size of the release sheet also becomes small, achieving a balance between resolution and peelability. On the other hand, in Comparative Examples 1, 2, and 5, although the peeling property was good, the resolution was low. Further, in Comparative Examples 3 and 4, although the high resolution was obtained, the peeling time became long, and the size of the release sheet became large. As described above, the effect of the photosensitive resin composition of the present invention was confirmed.

[Industrial availability]

According to the present invention, it is possible to provide a photosensitive resin composition, a photosensitive element, a method for forming a photoresist pattern, and a method for producing a printed circuit board, which have sufficient effects in improving resolution and photoresist peeling characteristics. .

1‧‧‧Photosensitive components

2‧‧‧Support film

3‧‧‧Photosensitive resin composition layer

4‧‧‧Protective film

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing a preferred embodiment of a photosensitive element of the present invention.

Claims (10)

A photosensitive resin composition comprising: (A) a binder polymer having a structural unit based on styrene, a structural unit based on benzyl (meth)acrylate, a structural unit based on (meth)acrylic acid, And a structural unit based on an alkyl (meth)acrylate having a dispersity of 1.0 to 2.0 and a weight average molecular weight of 20,000 to 50,000; (B) a photopolymerizable compound having an ethylene glycol chain and a propylene glycol chain in the molecule Both polyalkylene glycol di(meth)acrylates; and, (C) photopolymerization initiators. The photosensitive resin composition of claim 1, wherein the (A) binder polymer has 10 to 60 parts by mass of the styrene-based structural unit, and 10 parts by mass based on the total amount thereof. ~60 parts by mass of the benzyl (meth) acrylate-based structural unit, 10 to 60 parts by mass of the (meth)acrylic-based structural unit, and 1 part by mass or less and less than 15 parts by mass of the based (A) The structural unit of alkyl acrylate. The photosensitive resin composition of claim 1 or 2, wherein the (C) photopolymerization initiator has a hexaarylbiimidazole compound. The photosensitive resin composition of claim 1 or 2, which further contains (D) a sensitizing dye. The photosensitive resin composition of claim 1 or 2, which further contains (E) an amine compound. For example, the photosensitive resin composition of claim 1 or 2, In addition, the amount of the (C) photopolymerization initiator is 0.1 to 10 parts by mass based on 100 parts by mass of the total of the (A) binder polymer and the (B) photopolymerizable compound. The photosensitive resin composition of claim 1 or 2, wherein the (C) photopolymerization initiator is selected from the group consisting of aromatic ketones, anthraquinones, benzoin ether compounds, benzoin compounds, and benzyl groups. At least one of the group consisting of a 2,4,5-triaryl imidazole dimer and an acridine derivative. A photosensitive element comprising a support film and a photosensitive resin composition layer containing the photosensitive resin composition according to any one of claims 1 to 7 of the support film. A method for forming a photoresist pattern, comprising: a laminating step of laminating a photosensitive resin composition containing the photosensitive resin composition according to any one of claims 1 to 7 on a circuit-forming substrate a coating step of irradiating an active portion with a predetermined portion of the photosensitive resin composition layer to photoharden the exposed portion; and a developing step of forming a circuit for laminating the photosensitive resin composition layer The substrate is removed from portions other than the exposed portion of the photosensitive resin composition layer. A method of manufacturing a printed circuit board, comprising: etching or plating a circuit-forming substrate formed by a photoresist pattern according to a method for forming a photoresist pattern according to claim 9 to form a conductor pattern Type of steps.