JP2013073064A - Photosensitive resin composition and permanent mask resist using the same and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition which is excellent in flame retardancy while satisfying various characteristics required for a solder resist and can sufficiently reduce warpage and repulsion in mounting components, and provide a permanent mask resist using the same and a method for manufacturing the same.SOLUTION: There are provided a photosensitive resin composition comprising (A) a polymer having a carboxyl group, (B) a photopolymerizable compound having an ethylenically unsaturated bond, (C) a photopolymerization initiator, (D) a phosphorus-containing flame retardant and (E) a heat-curing agent, wherein (E) the heat-curing agent is a glycidyl etherified product of a phenol-formaldehyde polycondensate with epichlorohydrin and/or a derivative thereof and has an epoxy equivalent of 160 or more. There are also provided a permanent mask resist comprising a cured product of the photosensitive resin composition, and a method for manufacturing the permanent mask resist comprising the steps of: forming a photosensitive layer comprising the photosensitive resin composition; irradiating the photosensitive layer patternwise with actinic rays; and developing the photosensitive layer to form a permanent mask resist.

Description

  The present invention relates to a photosensitive resin composition, a permanent mask resist using the same, and a method for producing the same.

  In the printed wiring board manufacturing industry, conventionally, a solder resist (permanent mask resist) is formed on a printed wiring board. This solder resist has a role to prevent solder from adhering to unnecessary portions of the conductor layer of the printed wiring board in the soldering process for bonding the mounted part to the printed wiring board. When the printed wiring board is used later, it also serves as a permanent mask for preventing corrosion of the conductor layer and maintaining electrical insulation between the conductor layers.

  As a method for forming a solder resist, for example, a method of screen printing a thermosetting resin on a conductor layer of a printed wiring board is known. However, since such a method has a limit in increasing the resolution of a resist pattern. However, it has become difficult to cope with the recent increase in the density of printed wiring boards.

  Therefore, in order to achieve high resolution of the resist pattern, the photoresist method has been actively used. In this photoresist method, a photosensitive layer made of a photosensitive resin composition is formed on a substrate, the photosensitive layer is cured by exposure of a predetermined pattern, and an unexposed portion is removed by development to form a cured film of a predetermined pattern. To do.

  The photosensitive resin composition used in the photoresist method is roughly classified into a film type such as a dry film resist and a liquid type such as a solder resist ink. Liquid type such as solder resist ink has become mainstream.

  The photosensitive resin composition used for the above purpose is required to have characteristics such as sensitivity, developability, resolution, solder resistance, and HAST (Highly Accelerated Stress Test) properties. As such a photosensitive resin composition, for example, a photosensitive thermosetting resin composition described in the following patent document is known (see Patent Documents 1 and 2).

JP 2000-109541 A WO 06/109890 Pamphlet

  By the way, in recent years, regulations on flame retardancy of various industrial products against fire have become stricter, and materials used for printed wiring boards and the like are no exception. As a flame retardant method, a method of adding a halogen compound, an antimony compound, a phosphorus compound, a nitrogen compound, a boron compound, an inorganic filler, or the like is generally known.

  However, recently, with increasing interest in environmental issues and human safety issues, the focus has shifted to non-polluting, low toxic and safety, not only flammable but also harmful gases and fuming substances. Reduction is being demanded. In response, flame retardant substrates that do not use halogen compounds or antimony compounds have already been developed and put into practical use.

  Further, along with recent downsizing and thinning of electronic devices, there is an increasing demand for reduction of warpage and repulsive force when mounting components together with flame retardant technology.

  In addition, with the miniaturization of circuits, there are an increasing number of cases in which a defect phenomenon (bleed) in which a resist component oozes out in a resist opening in a hot press process becomes a problem. However, the flame retardants currently on the market, when added in a large amount, will deteriorate the physical properties of the cured film of the photosensitive resin composition, increase repulsion and cracks, increase bleed in the hot press process, insulation reliability Cause a decline. For this reason, while selecting the flame retardant with these characteristic deterioration less, also in resin compositions other than a flame retardant, the design which can ensure a flame retardance by addition of a little flame retardant is required.

  Further, the surface of the photosensitive resin composition layer formed on the substrate in the photoresist method is preferably one having a small tack property (stickiness) from the viewpoint of workability, but the conventional photosensitive resin composition has a tack property. Was not enough to satisfy.

  In view of the above circumstances, the present invention is a photosensitive resin composition that is excellent in flame retardancy and can sufficiently reduce warpage, resilience, and tackiness during component mounting while satisfying various properties required for a solder resist, and An object of the present invention is to provide a permanent mask resist using the same and a manufacturing method thereof.

  As a result of intensive studies to achieve the above object, the present inventors have found that the above object can be achieved by using a compound having a specific structure and epoxy equivalent, and have completed the present invention. .

  That is, the present invention includes (A) a polymer having a carboxyl group, (B) a photopolymerizable compound having an ethylenically unsaturated bond, (C) a photopolymerization initiator, (D) a phosphorus-containing flame retardant, (E) heat In the photosensitive resin composition containing a curing agent, the (E) thermosetting agent is a diglycidyl etherified product of epichlorohydrin of phenol / formaldehyde polycondensate and / or a derivative thereof, and an epoxy equivalent is 160 or more. A photosensitive resin composition is provided.

  The photosensitive resin composition of the present invention is obtained by curing the photosensitive resin composition because of having the above-described structure, which has less surface stickiness in the unexposed area before development, can be developed with a dilute aqueous alkali solution, and The flame retardancy, plating resistance, soldering heat resistance, and HAST resistance of the cured film can be satisfied at a high level, and warpage and repulsion during component mounting can be suppressed, thereby improving workability. Therefore, according to the photosensitive resin composition of the present invention, a cured film having sufficient flame retardancy can be efficiently formed with high resolution.

  Further, according to the photosensitive resin composition of the present invention, since the flame retardancy of the cured film can be made sufficiently high without containing a halogen compound or an antimony compound, for example, the environmental load of a printed wiring board And toxicity can be reduced. In particular, when the photosensitive resin composition of the present invention is applied to a non-halogen-based or non-antimony-based flame retardant substrate, the above-described effects are more effectively exhibited.

  In addition, the compound (A) having a carboxyl group includes (a) an epoxy acrylate compound having an ethylenically unsaturated group and two or more hydroxyl groups obtained by reacting a diglycidyl compound and (meth) acrylic acid, and ( It is preferably a reaction product of b) a diisocyanate compound and (c) a diol compound having a carboxyl group. Thereby, alkali developability, flame retardancy, and flexibility (bending resistance, low warpage, low repulsion) can be improved.

  The (D) phosphorus-containing flame retardant is preferably a phosphinic acid salt represented by the following general formula (1).

[In General Formula (1), A and B each independently represent a linear or branched alkyl group or aryl group having 1 to 6 carbon atoms, and M represents Mg, Ca, Al, Sb, Sn, Ge. , Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, and K. At least one metal selected from the group consisting of K and m is an integer of 1 to 4. ]
Thereby, the cured film obtained by hardening | curing the photosensitive resin composition can have sufficient flame retardance.

  The photosensitive resin composition of the present invention can efficiently form a cured film having sufficient flame retardancy with high resolution, and has sufficient flexibility, so that it is a permanent mask for printed wiring boards, particularly flexible printed wiring boards. It is preferable that it is used for the permanent mask resist for forming. The method for producing a permanent mask resist of the present invention comprises a step of providing a photosensitive layer comprising the above-mentioned photosensitive resin composition on a substrate, a step of pattern irradiating the photosensitive layer with actinic rays, and developing the photosensitive layer. And a step of forming a permanent mask resist.

  Using the photosensitive resin composition of the present invention, according to the permanent mask resist composed of the cured product and the method for producing the same, by providing the photosensitive layer composed of the photosensitive resin composition of the present invention, sufficient flame retardancy is provided. It is possible to efficiently form a cured film having high resolution, and further, it is possible to reduce warpage and repulsion during component mounting.

  Further, according to the permanent mask resist of the present invention and the manufacturing method thereof, since it has sufficient flame retardancy without using a halogen compound or an antimony compound, the printed wiring board has a low environmental load, low toxicity, and high resolution. Efficient production is possible.

  According to the present invention, a photosensitive resin composition capable of efficiently forming a cured film excellent in workability and excellent in alkali developability, flame retardancy, and flexibility, particularly in a process up to development, and high resolution, and It is possible to provide a permanent mask resist using the above and a manufacturing method thereof.

  Hereinafter, embodiments of the present invention will be described in detail. In the present invention, (meth) acrylic acid means acrylic acid and methacrylic acid corresponding thereto, (meth) acrylate means acrylate and corresponding methacrylate, and (meth) acryloyl group means acryloyl group. And the corresponding methacryloyl group.

[Photosensitive resin composition]
First, the photosensitive resin composition of the present invention will be described. The photosensitive resin composition of the present invention is
(A) a polymer having a carboxyl group,
(B) a photopolymerizable compound having an ethylenically unsaturated bond,
(C) a photopolymerization initiator,
(D) a phosphorus-containing flame retardant,
(E) In the photosensitive resin composition containing a thermosetting agent, the (E) thermosetting agent is a glycidyl etherified product of epichlorohydrin of phenol / formaldehyde polycondensate and / or a derivative thereof, and an epoxy equivalent is It is a photosensitive resin composition which is 160 or more.

Hereinafter, each component contained in the photosensitive resin composition of the present invention will be described.
<(A) component>
Examples of the component (A) polymer having a carboxyl group include acrylic resin, polyurethane, vinyl group-containing epoxy resin, epoxy resin, phenoxy resin, polyester, polyamide, polyimide, polyamideimide, polyesterimide, polycarbonate, melamine resin, and polyphenylene. Known resins such as sulfide and polyoxybenzoyl and acid-modified resins thereof having a carboxyl group in the molecule can be mentioned. These can be used alone or in combination of two or more.

  The component (A) includes a polymer having a carboxyl group in the molecule from the viewpoint of further improving alkali developability.

  The polymer having a carboxyl group in the molecule preferably includes a polymerizable prepolymer having a carboxyl group and an ethylenically unsaturated group from the viewpoint of further improving the plating resistance and thermal shock resistance of the resulting cured film. .

  Among them, (a) an epoxy acrylate compound having an ethylenically unsaturated group and two or more hydroxyl groups obtained by reacting a diglycidyl compound and (meth) acrylic acid, (b) a diisocyanate compound, and (c) a carboxyl group. A polyurethane compound obtained by reacting the diol compound with the diol compound can be suitably used. Thereby, the effect of this invention can be further improved with the combination with (E) component mentioned later.

  The polyurethane compound includes (a) an epoxy acrylate compound having an ethylenically unsaturated group and two or more hydroxyl groups obtained by reacting a glycidyl compound and (meth) acrylic acid (hereinafter referred to as “raw material epoxy acrylate”), ( b) A diisocyanate compound (hereinafter referred to as “raw material diisocyanate”) and (c) a diol compound having a carboxyl group (hereinafter referred to as “raw material diol”) are obtained as raw material components. First, these raw material components will be described.

  Examples of the raw material epoxy acrylate include compounds obtained by reacting (meth) acrylic acid with glycidyl compounds such as bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, novolac type epoxy compounds, and epoxy compounds having a fluorene skeleton. .

  As the raw material diisocyanate, any compound having two isocyanato groups can be used without particular limitation. Examples of the diisocyanate compound include phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, tridenic diisocyanate, hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate, arylene sulfone ether diisocyanate. , Allyl cyanide diisocyanate, N-acyl diisocyanate, trimethylhexamethylene diisocyanate, 1,3-bis (isocyanatemethyl) cyclohexane, norbornane-diisocyanate methyl, and the like.

  The raw material diol is a compound having two hydroxyl groups and a carboxyl group in the molecule. The hydroxyl group is preferably an alcoholic hydroxyl group highly reactive with isocyanate. Examples of such diol compounds include dimethylolpropionic acid and dimethylolbutanoic acid.

  In addition, diol compounds other than those described above (for example, ethylene glycol, propylene glycol, etc.) can be used in combination as the raw material diol. By combining diol compounds other than those described above, it is possible to easily adjust the acid value and double bond equivalent of the component (A).

  Next, an example of a process for producing a polyurethane compound using the above-described raw material components will be described.

  That is, in the production process of the polyurethane compound, first, the raw material epoxy acrylate and the raw material diol are reacted with the raw material diisocyanate. In such a reaction, a so-called urethanization reaction occurs mainly between the hydroxyl group in the raw material epoxy acrylate and the isocyanate group in the raw material diisocyanate, and between the hydroxyl group in the raw material diol and the isocyanate group in the raw material diisocyanate. By this reaction, for example, a structural unit containing a polymerizable unsaturated double bond derived from a raw material epoxy acrylate and a structural unit containing a carboxyl group derived from a raw material diol are introduced via a structural unit derived from a raw material diisocyanate. A polyurethane compound polymerized alternately or blockwise is obtained.

  In the production process of the polyurethane compound described above, a diol compound different from these may be further added in addition to the raw material epoxy acrylate, the raw material diol and the raw material diisocyanate. Thereby, it becomes possible to change the main chain structure of the obtained polyurethane compound, and the characteristics such as the acid value described later can be adjusted to a desired range. Moreover, in each process mentioned above, you may use a catalyst etc. suitably.

  As said polyurethane compound, the compound which has a structure represented by following General formula (2) is mentioned, for example.

In the formula, R ¹¹ represents a residue of the raw material epoxy acrylate, R ¹² represents a residue of the raw material isocyanate, R ¹³ represents an alkyl group having 1 to 5 carbon atoms, and R ¹⁴ represents a hydrogen atom or a methyl group. Show. In addition, a residue means the structure of the part remove | excluding the functional group used for the coupling | bonding from the raw material component. Specifically, as R ¹¹ , for example, bis (4-oxyphenyl) -methane, 2,2-bis (4-oxyphenyl) -propane, 2,2-bis (4-oxyphenyl) -1, Examples thereof include bisphenol A skeletons such as 1,1,3,3,3-hexafluoropropane, bisphenol F skeletons, novolac skeletons, and fluorene skeletons. Examples of R ¹² include phenylene, tolylene, xylylene, and tetramethylxylylene. , Diphenylmethylene, hexamethylene, trimethylhexamethylene, dicyclohexylmethylene, and isophorone. Moreover, as a C1-C5 alkyl group, a methyl group, an ethyl group, a propyl group, a butyl group, an isobutyl group, a pentyl group, an amyl group etc. are mentioned.

  By containing a polyurethane compound having the structure of the general formula (2) in the photosensitive resin composition, alkali developability, flame retardancy, flexibility (bending resistance, low warpage, low repulsion) Can be further improved.

  As the polyurethane compound having the structure represented by the general formula (2), a commercially available product can be used. For example, UXE-3044, UXE-3061, UXE-3063, UXE-3064, UXE-3073 (product) Name, manufactured by Nippon Kayaku Co., Ltd.).

  In addition, as the component (A), an addition reaction product obtained by adding a saturated or unsaturated polybasic acid anhydride to an esterified product of an epoxy compound and an unsaturated monocarboxylic acid can also be used. As the epoxy compound, for example, bisphenol type epoxy compounds obtained by reacting bisphenol A type, bisphenol F type and epichlorohydrin are suitable, and bisphenol A types such as GY-260, 255, XB-2615 manufactured by Ciba Geigy, Epoxy compounds such as bisphenol F type, hydrogenated bisphenol A type, amino group-containing, alicyclic or polybutadiene-modified are preferably used. Also suitable are novolak-type epoxy compounds obtained by reacting novolaks obtained by reacting phenol, cresol, halogenated phenols and alkylphenols with formaldehyde in the presence of an acidic catalyst and epichlorohydrin. YDCN manufactured by Toto Kasei Co., Ltd. -701, 704, YDPN-638, 602, DEN-431, 439 manufactured by Dow Chemical Co., Ltd., EPN-1299 manufactured by Ciba Geigy Co., Ltd., N-730, 770, 865, 665, 673 manufactured by Dainippon Ink & Chemicals, Inc. , VH-4150, 4240, Nippon Kayaku Co., Ltd. EOCN-120, and the like.

  In addition to bisphenol type and novolak type epoxy compounds, for example, salicylaldehyde-phenol or cresol type epoxy compounds (Nippon Kayaku Co., Ltd. EPPN502H, FAE2500, etc.) are preferably used. Further, for example, Epicoat 828, 1007, 807 manufactured by Japan Epoxy Resin Co., Ltd., Epicron 840, 860, 3050 manufactured by Dainippon Ink & Chemicals, Inc. (DIC Corporation), DER-330, 337, 361 manufactured by Dow Chemical Co., Ltd., Daicel Chemical Industry Co., Ltd. Celoxide 2021, Mitsubishi Gas Chemical Co., Ltd. TETRAD-X, C, Nippon Soda Co., Ltd. EPB-13, 27, etc. can be used. Mixtures or block copolymers of these can also be used.

  Examples of the unsaturated monocarboxylic acid include (meth) acrylic acid, crotonic acid, cinnamic acid, saturated or unsaturated polybasic acid anhydrides and (meth) acrylates having one hydroxyl group per molecule, or saturated or unsaturated. Reactions of half-ester compounds of saturated dibasic acids with unsaturated monoglycidyl compounds, eg phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, succinic acid and hydroxyethyl (meth) acrylate, hydroxypropyl Examples thereof include reactants obtained by reacting (meth) acrylate, tris (hydroxyethyl) isocyanurate di (meth) acrylate, and glycidyl (meth) acrylate at an equimolar ratio by a conventional method. These unsaturated monocarboxylic acids can be used alone or in combination. Of these, acrylic acid is preferred.

  Examples of the saturated or unsaturated polybasic acid anhydride include anhydrides such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, succinic acid, and trimellitic acid.

  Moreover, Nippon Kayaku Co., Ltd. product ZAR-1035, CCR-1171H, PCR-1050 etc. are mentioned as a polymeric prepolymer which has a carboxyl group and an ethylenically unsaturated group.

As the component (A), a vinyl copolymer compound obtained by using (meth) acrylic acid and (meth) acrylic acid alkyl ester as a copolymerization component can also be used.
For example, it can be obtained by radical polymerization of (meth) acrylic acid and (meth) acrylic acid alkyl ester as a copolymerization component.

  Examples of the (meth) acrylic acid alkyl ester include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid propyl ester, (meth) acrylic acid butyl ester, and (meth) acrylic acid. Examples include pentyl ester, (meth) acrylic acid hexyl ester, (meth) acrylic acid heptyl ester, (meth) acrylic acid octyl ester, and (meth) acrylic acid 2-ethylhexyl ester.

  As said vinyl type copolymer compound, you may use the compound obtained by copolymerizing the vinyl monomer which can be copolymerized with these with (meth) acrylic-acid alkylester and (meth) acrylic acid. Examples of such vinyl monomers include acrylamide such as diacetone acrylamide, ethers of vinyl alcohol such as acrylonitrile and vinyl-n-butyl ether, tetrahydrofurfuryl ester of (meth) acrylic acid, dimethylaminoethyl (meth) acrylate. Ester, (meth) acrylic acid diethylaminoethyl ester, (meth) acrylic acid glycidyl ester, 2,2,2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, α -(Meth) acrylic monomers such as bromo (meth) acrylic acid, α-chloro (meth) acrylic acid, β-furyl (meth) acrylic acid, and β-styryl (meth) acrylic acid, maleic acid, Maleic anhydride, monomethyl maleate Monoethyl maleate, and maleic acid monomers such as maleic acid monoisopropyl, fumaric acid, cinnamic acid, alpha-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid, styrene, and a vinyl toluene. These can be used alone or in combination of two or more.

  Moreover, the copolymer which introduce | transduced the ethylenically unsaturated bond into the side chain and / or terminal of the vinyl monomer copolymer which can be copolymerized with (meth) acrylic-acid alkylester and (meth) acrylic acid is also suitable. Examples of vinyl monomer copolymers include vinyl polymerizable monomers having a carboxyl group such as acrylic acid, methacrylic acid, fumaric acid, cinnamic acid, crotonic acid, and itaconic acid, and methyl methacrylate, methyl acrylate, ethyl methacrylate, and ethyl acrylate. , N-propyl methacrylate, n-propyl acrylate, butyl methacrylate, butyl acrylate, lauryl methacrylate, lauryl acrylate, 2-ethylhexyl methacrylate, 2-ethylhexyl acrylate, vinyl toluene, N-vinyl pyrrolidone, α-methyl styrene, 2-hydroxyethyl Methacrylate, 2-hydroxyethyl acrylate, acrylamide, acrylonitrile, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate Use vinyl polymerizable monomers such as those obtained by general solution polymerization using polymerization initiators such as azobisisobutyronitrile, azobisdimethylvaleronitrile, and benzoyl peroxide in an organic solvent. Can do.

  The content of the component (A) is preferably 20 to 80% by mass, and more preferably 30 to 70% by mass based on the total amount of solid organic compound in the photosensitive resin composition.

  (A) It is preferable that the acid value of a component is 25-140 mgKOH / g, It is more preferable that it is 45-100 mgKOH / g, It is further more preferable that it is 55-80 mgKOH / g. When the acid value of the component (A) is 25 mgKOH / g or more, the developability of the photosensitive resin composition with an alkaline aqueous solution is improved and excellent resolution is easily obtained, and the acid value is 140 mgKOH / g or less. Thereby, it becomes easy to obtain the cured film of the photosensitive resin composition excellent in flexibility.

The acid value of the component (A) can be measured by the following method. First, after precisely weighing about 1 g of the resin solution as the component (A), 30 g of acetone is added to the resin solution to uniformly dissolve the resin solution. Next, an appropriate amount of phenolphthalein as an indicator is added to the solution, and titration is performed using a 0.1N aqueous KOH solution. Then, the acid value is calculated from the titration result by the following formula (3) (where Vf represents the titration amount (mL) of the KOH aqueous solution, and Wp represents the mass (g) of the resin solution as the component (A). , I represents the ratio (% by mass) of the nonvolatile content of the resin solution as the component (A).

Acid value (mgKOH / g) = 10 × Vf × 56.1 / (Wp × I) (3)

  The weight average molecular weight of the component (A) is 5000 to 20000 from the viewpoint of improving the film formability of the photosensitive resin composition, the crack resistance and the HAST resistance of the cured film, and may be 8500 to 15500. More preferably, it is 7000-15000. When the average molecular weight is greater than 5,000, stickiness of the photosensitive resin composition after printing and drying is reduced, and contamination due to adhesion of the resin composition to the apparatus and contamination of the surface of the photosensitive layer due to non-adherence of foreign matter are less likely to occur. can do. Moreover, when the average molecular weight is smaller than 20000, the plate separation at the time of screen printing of the resin composition is improved, and development with a dilute alkaline aqueous solution can be made possible.

(A) The weight average molecular weight of a component can be calculated | required by the standard polystyrene conversion value by a gel permeation chromatography (GPC). The measurement conditions in GPC are as follows.
Column: Gelpack GL-R440 + GL-R450 + GL-R400M
Flow rate: 2.05 mL / min
Concentration: 120 mg / 5 mL
Injection volume: 200 μL
Eluent: THF

<(B) component>
Specific examples of the compound (B) having an ethylenically unsaturated bond include, for example, a bisphenol A (meth) acrylate compound; a compound obtained by reacting a polyhydric alcohol with an α, β-unsaturated carboxylic acid; A compound obtained by reacting a glycidyl group-containing compound with an α, β-unsaturated carboxylic acid; a urethane monomer or urethane oligomer such as a (meth) acrylate compound having a urethane bond; in addition to these, nonylphenoxypolyoxy Phthalic acid compounds such as ethylene acrylate; γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyalkyl-β ′-(meth) acryloyloxyalkyl-o-phthalate ; (Meth) acrylic acid alkyl ester, ethylene oxide (EO) modified nonylphenyl (meth) acrylate and the like can be exemplified. These can be used individually by 1 type or in combination of 2 or more types.

  Among these, it is preferable to include a bisphenol A-based (meth) acrylate compound in terms of excellent adhesion and resolution. Examples of bisphenol A-based (meth) acrylate compounds include 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane and 2,2-bis (4-((meth) acryloxypolypropoxy). ) Phenyl) propane, 2,2-bis (4-((meth) acryloxypolybutoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypolyethoxypolypropoxy) phenyl) propane, etc. Can be mentioned.

  The content of the component (B) is preferably 5 to 80% by mass from the viewpoint of resolution and flame retardancy, and the content of the component (B) in the photosensitive resin composition is preferably 10 to 80%. More preferably, it is mass%. When the content of the component (B) is less than 5% by mass, the warping and rebound characteristics during mounting tend to be inferior, and when the content exceeds 80% by mass, the flame retardancy tends to decrease.

<(C) component>
Examples of the photopolymerization initiator that is the component (C) of this embodiment include benzophenone, N, N′-tetraalkyl-4,4′-diaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4 -Morpholinophenyl) -butanone-1, 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1, etc. aromatic ketones; benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, etc. Benzoin ether; benzyl derivatives such as benzyldimethyl ketal; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole 2-mer (2- (o-fluorophenyl) -4,5-diphenylimidazole) 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (2,4-dimethoxyphenyl) ) 4,4,5-triarylimidazole dimers such as 4,5-diphenylimidazole dimer; acridine derivatives such as 9-phenylacridine, 1,7-bis (9,9′-acridinyl) heptane; N-phenylglycine, N-phenylglycine derivatives, coumarin compounds and the like can be mentioned. These can be used singly or in combination of two or more.

  From the viewpoint of improving sensitivity and resolution, the component (C) according to this embodiment preferably contains an aromatic ketone, and particularly preferably contains an α-aminoalkylphenone compound. Examples of the α-aminoalkylphenone compound include 2-methyl-1- [4- (methylthio) phenyl] -2-morpholino-propanone-1.

  As for content of (C) component, it is preferable that content of (C) component in the photosensitive resin composition is 0.1-10 mass% from a viewpoint of photosensitivity, and 0.2-5 mass % Is more preferable.

<(D) component>
The phosphorus-containing flame retardant that is the component (D) is preferably a phosphinic acid salt represented by the following general formula (1).

［一般式（１）中、Ａ及びＢは各々独立に、直鎖状の若しくは枝分かれした炭素数１〜６のアルキル基又はアリール基を示し、ＭはＭｇ、Ｃａ、Ａｌ、Ｓｂ、Ｓｎ、Ｇｅ、Ｔｉ、Ｚｎ、Ｆｅ、Ｚｒ、Ｃｅ、Ｂｉ、Ｓｒ、Ｍｎ、Ｌｉ、Ｎａ及びＫからなる群より選択される金属類の少なくとも１種であり、ｍは１〜４の整数である。]
Ａ、Ｂの具体例としては、例えば、メチル基、エチル基、ｎ−プロピル基、イソプロピル基、ｎ−ブチル基、第三−ブチル基、ｎ−ペンチル基、フェニル基等が挙げられる。

[In General Formula (1), A and B each independently represent a linear or branched alkyl group or aryl group having 1 to 6 carbon atoms, and M represents Mg, Ca, Al, Sb, Sn, Ge. , Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, and K. At least one metal selected from the group consisting of K and m is an integer of 1 to 4. ]
Specific examples of A and B include, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, tert-butyl group, n-pentyl group, and phenyl group.

  Further, 80% by mass or more of the phosphinic acid salt may have a particle size (particle size) of 10 μm or less from the viewpoint of reliability when used for the photosensitive resin composition and the permanent mask resist. It is preferably 5 μm or less, more preferably 3 μm or less. When the particle size of the particles exceeds 10 μm, the appearance of the coating film of the photosensitive resin composition tends to be deteriorated, and the production of a high-resolution printed wiring board tends to be difficult.

  The component (D) is preferably contained so that the phosphorus content in the photosensitive resin composition is in the range of 1.5 to 5.0% by mass. When the phosphorus content is 1.5% by mass or more, necessary flame retardancy can be secured, and by 5.0% by mass or less, low warpage and low rebound flexibility are abundant. It is possible to form a cured film. Phosphinates can be used alone or in combination of two or more.

  A commercial item can be used for the phosphinic acid salt, for example, EXOLIT OP 930, EXOLIT OP 935, EXOLIT OP 940 (all are the Clariant Japan Co., Ltd. make, brand name) can also be used.

<(E) component>
The thermosetting agent as component (E) is a glycidyl etherified product of epichlorohydrin of phenol / formaldehyde polycondensate and / or its derivative, and its epoxy equivalent (g / eq, hereinafter the same) is 160 or more. The epoxy equivalent is preferably 300 or more. Moreover, it is preferable that it is 5000 or less. By setting the epoxy equivalent to 160 or more, surface tack after drying and bleed during hot pressing are reduced, and a cured film with low warpage and low resilience is obtained. Moreover, by making an epoxy equivalent into 5000 or less, developability improves and the insulation reliability of a cured film improves. The epoxy equivalent can be measured by the following method.

(Measurement method of epoxy equivalent)
About 4 (g) of the epoxy resin sample is precisely weighed in a 100 ml beaker, and 50 ml of methylene chloride is added and dissolved. To this, 10 ml of tetraethylammonium bromide / acetic acid solution and 2 to 3 drops of crystal violet indicator are added and titrated with 0.1N perchloric acid / acetic acid solution. The end point of titration is the color change point of the indicator. In addition, a blank test is performed in the same manner, and the epoxy equivalent is determined by the following equation.
<Epoxy equivalent>
(G / eq) = 1000 × W × α / ((V−B) × N × F)
W: Sample mass
^* Α: Nonvolatile content of epoxy resin sample V: Titration amount of 0.1N perchloric acid / acetic acid solution (ml)
B: Titration of 0.1N perchloric acid / acetic acid solution in blank test (ml)
N: Normality of 0.1N perchloric acid / acetic acid solution (eq / 1)
F: Potency of 0.1N perchloric acid / acetic acid solution
^* Measurement method of non-volatile content (α) of epoxy resin sample About 1 (g) of epoxy resin sample was precisely weighed on an aluminum dish with a diameter of 50 mm that was precisely weighed in advance (W ₁ ) and thinly stretched (W ₂ ), 108 After drying at 3 ° C. for 3 hours, it is allowed to cool and the mass (W ₃ ) of the aluminum dish is measured.
The resin fraction α is determined from these mass differences.
<Resin fraction; α> = (W ₃ −W ₁ ) / (W ₂ −W ₁ )
W ₁ : Mass of aluminum dish (g)
W ₂ : Mass of epoxy resin sample + aluminum dish (g)
W ₃ ; epoxy resin sample after drying + mass of aluminum dish (g)

  The thermosetting agent as component (E) is a glycidyl etherified product of a phenol / formaldehyde polycondensate with epichlorohydrin and / or a derivative thereof. A modified one can also be used. For example, acrylic acid or methacrylic acid is added to provide photoreactivity, reactive phosphorus compounds, reactive nitrogen compounds, etc. are added to improve flame retardancy, and polyethylene glycol is added for flexibility. Such as those imparted with sex.

  Moreover, it can also be used in combination with another thermosetting agent. Examples of the thermosetting agent to be combined include thermosetting compounds such as epoxy resins, phenol resins, urea resins, and melamine resins. Examples of the epoxy resin include bisphenol A type tertiary fatty acid-modified polyol epoxy resin; diglycidyl esters such as diglycidyl phthalate and diglycidyl tetrahydrophthalate, and diglycidyl amines such as diglycidyl aniline and diglycidyl toluidine. Etc. These may be used alone or in combination of two or more.

  As the thermosetting agent, a block isocyanate compound which is a latent thermosetting agent can also be used. Examples of the blocked isocyanate compound include polyisocyanate compounds blocked with a blocking agent such as an alcohol compound, a phenol compound, ε-caprolactam, an oxime compound, and an active methylene compound. Examples of blocked polyisocyanate compounds include 4,4-diphenylmethane disissocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene 1,5-diisocyanate, o-xylene diisocyanate, and m-xylene. Aromatic polyisocyanates such as diisocyanates, 2,4-tolylene dimers, aliphatic polyisocyanates such as hexamethylene diisocyanate, 4,4-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, and alicyclic polyisocyanates such as bicycloheptane triisocyanate An aromatic polyisocyanate is preferable from the viewpoint of heat resistance, and an aliphatic polyisocyanate or an alicyclic polyisocyanate is preferable from the viewpoint of preventing coloring.

  (E) From content of a flame retardance and insulation reliability, it is preferable that content in the photosensitive resin composition is 5-60 mass%, and, as for content of (E) component, it is 10-50 mass%. Is more preferable. When the content is 5% by mass or more, the surface tack after drying, the flexibility after curing, the chemical resistance, the insulation reliability, and the flame retardancy are improved, and the resolution is achieved by setting the content to 60% by mass or less. -Good developability.

  In addition, the photosensitive resin composition of the present invention includes a dye such as malachite green, a photochromic agent such as leuco crystal violet, a plasticizer such as a thermochromic inhibitor or p-toluenesulfonamide, phthalocyanine blue, if necessary. Phthalocyanine-based organic pigments such as azo-based pigments, inorganic pigments such as titanium dioxide, silica, alumina, talc, calcium carbonate or barium sulfate, and other fillers, antifoaming agents, stabilizers, and adhesion-imparting agents , A leveling agent, an antioxidant, a fragrance, an imaging agent, or the like. These components are preferably contained in an amount of about 0.01 to 20% by mass as the content in the photosensitive resin composition. Moreover, said component can be used individually by 1 type or in combination of 2 or more types.

  Furthermore, the photosensitive resin composition of the present invention may contain a solvent such as methanol, ethanol, acetone, methyl ethyl ketone, methyl cellosolve, ethyl cellosolve, toluene, N, N-dimethylformamide, propylene glycol monomethyl ether or the like as necessary. It can melt | dissolve in a mixed solvent and can apply | coat as a solution of solid content about 30-70 mass%.

[Photosensitive film]
Next, the photosensitive film which can be used suitably for the manufacturing method of the permanent mask resist and permanent mask resist of this invention is demonstrated.
A photosensitive film consists of a photosensitive laminated body provided with the support body and the photosensitive resin composition layer which consists of the photosensitive resin composition of this invention formed on this support body. On the photosensitive resin composition layer, you may further provide the protective film which coat | covers this photosensitive resin composition layer.

  As the support, for example, a polymer film having heat resistance and solvent resistance such as polyester such as polyethylene terephthalate, polypropylene, and polyethylene can be used. The thickness of the support (polymer film) is preferably 5 to 25 μm. If the thickness is less than 5 μm, the support film tends to be broken when the support film is peeled off before development. If it exceeds, the resolution tends to decrease. In addition, you may use the said polymer film laminated | stacked on both surfaces of the photosensitive resin composition layer as a support body and a protective film.

  As the protective film, for example, a polymer film having heat resistance and solvent resistance such as polyester such as polyethylene terephthalate, polypropylene, and polyethylene can be used. Examples of commercially available products include, for example, trade names made by Oji Paper Co., Ltd .: Alphan MA-410, E-200C, polypropylene films made by Shin-Etsu Film Co., Ltd., trade names made by Teijin Limited: PS-25, etc. Examples thereof include polyethylene terephthalate films such as PS series, but are not limited thereto.

The thickness of the protective film is preferably 1 to 100 μm, more preferably 5 to 50 μm, further preferably 5 to 30 μm, and particularly preferably 15 to 30 μm. If this thickness is less than 1 μm, the protective film tends to be broken during lamination, and if it exceeds 100 μm, the cost tends to be inferior. The protective film preferably has a smaller adhesive strength between the photosensitive resin composition layer and the protective film than the adhesive strength between the photosensitive resin composition layer and the support, and is preferably a low fisheye film. .
Fisheye is a material in which foreign materials, undissolved materials, oxidatively deteriorated materials, etc. are incorporated into the film when the material is melted and kneaded, extruded, biaxially stretched, or casted to produce a film. It is.

  The photosensitive resin composition layer is prepared by dissolving the photosensitive resin composition of the present invention in a solvent as described above to obtain a solution (coating solution) having a solid content of about 30 to 70% by mass. The coating liquid is preferably formed by coating on a support and drying. The application can be performed by a known method using, for example, a roll coater, comma coater, gravure coater, air knife coater, die coater, bar coater or the like. Moreover, the said drying can be performed at 70-150 degreeC and about 5 to 30 minutes. The amount of the remaining organic solvent in the photosensitive resin composition is preferably 3% by mass or less with respect to the total amount of the photosensitive resin composition from the viewpoint of preventing diffusion of the organic solvent in the subsequent step.

  Although the thickness of the said photosensitive layer changes with uses, it is preferable that it is 5-200 micrometers by the thickness after drying, It is more preferable that it is 15-60 micrometers, It is especially preferable that it is 20-50 micrometers. If the thickness is less than 5 μm, it tends to be difficult to apply industrially, and if it exceeds 200 μm, the sensitivity and resolution inside the photosensitive resin composition layer tend to be lowered.

  The photosensitive film may further have an intermediate layer such as a cushion layer, an adhesive layer, a light absorption layer, and a gas barrier layer. Moreover, the obtained photosensitive film can be wound up and stored in a sheet form or a roll around a core. In addition, it is preferable to wind up so that a support body may become the outermost part in this case. From the viewpoint of end face protection, it is preferable to install an end face separator on the end face of the roll-shaped photosensitive film roll, and it is preferable to install a moisture-proof end face separator from the viewpoint of edge fusion resistance. Moreover, as a packing method, it is preferable to wrap and package in a black sheet with low moisture permeability. Examples of the winding core include plastics such as polyethylene resin, polypropylene resin, polystyrene resin, polyvinyl chloride resin, and ABS resin (acrylonitrile-butadiene-styrene copolymer).

[Method of forming resist pattern]
Next, a method for forming a resist pattern using the above photosensitive film will be described.

A photosensitive layer made of the above-described photosensitive resin composition is formed on a substrate on which a resist is to be formed. The protective film of the photosensitive film is peeled from the photosensitive resin composition layer, and the exposed surface is adhered by a laminate or the like so as to cover the conductor layer having a circuit pattern formed on the substrate. A method of laminating under reduced pressure is also preferable from the viewpoint of improving adhesion and followability.
In addition, the photosensitive resin composition can also be apply | coated on a board | substrate by well-known methods, such as the method of apply | coating the varnish of the photosensitive resin composition with a screen printing method or a roll coater.

  Next, an exposure process is performed in which a predetermined portion of the photosensitive resin composition layer is irradiated with an actinic ray through a mask pattern, and the photosensitive resin composition layer in the irradiated portion is photocured.

  Further, when a support is present on the photosensitive layer, after removing the support, by removing a portion that has not been photocured by wet development or dry development (unexposed portion) and developing, A resist pattern (permanent mask resist) can be formed.

  In the case of the above-described wet development, as the developer, an alkaline aqueous solution, an aqueous developer, an organic solvent, or the like that is safe and stable and has good operability is used according to the type of the photosensitive resin composition. Further, as a developing method, a known method such as spraying, rocking dipping, brushing, scraping or the like is appropriately employed.

  Examples of the base of the alkaline aqueous solution include alkali metals such as lithium hydroxide, sodium hydroxide and potassium hydroxide which are hydroxides of lithium, sodium and potassium, carbonates or bicarbonates such as alkali metals and ammonium. Alkaline carbonate or bicarbonate, alkali metal phosphate sodium phosphate, potassium phosphate, etc., alkali metal pyrophosphate sodium pyrophosphate, potassium pyrophosphate etc., safe and stable, operability The one with good is used.

  Examples of the alkaline aqueous solution include a dilute solution of 0.1 to 5% by mass of sodium carbonate, a dilute solution of 0.1 to 5% by mass of potassium carbonate, and a dilute solution of 0.1 to 5% by mass of sodium hydroxide. A solution, a dilute solution of 0.1 to 5% by mass sodium tetraborate is preferred, and the pH is preferably in the range of 9 to 11. The temperature of the alkaline aqueous solution is adjusted according to the developability of the photosensitive layer, and is preferably 20 to 50 ° C. Furthermore, a small amount of an organic solvent such as a surfactant or an antifoaming agent may be mixed in the alkaline aqueous solution in order to promote development.

  As the aqueous developer, one comprising water and an alkaline aqueous solution or one or more organic solvents is used. Here, as the base of the alkaline aqueous solution, in addition to those described above, for example, borax, sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2-amino-2-hydroxymethyl-1,3- Examples include propanediol, 1,3-diaminopropanol-2, and morpholine. The pH of such an aqueous developer is preferably as small as possible within a range where development processing can be sufficiently performed, preferably pH 8 to 12, and more preferably pH 9 to 10.

  Examples of the organic solvent include acetone, ethyl acetate, alkoxyethanol having an alkoxy group having 1 to 4 carbon atoms, ethyl alcohol, isopropyl alcohol, butyl alcohol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, and diethylene glycol monobutyl ether. . The concentration of such an organic solvent is usually preferably 2 to 90% by mass. Moreover, the temperature of such an organic solvent can be adjusted according to developability. Furthermore, such organic solvents can be used alone or in combination of two or more. Examples of the organic solvent-based developer used alone include 1,1,1-trichloroethane, N-methylpyrrolidone, N, N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone. Furthermore, a small amount of an organic solvent such as a surfactant or an antifoaming agent may be mixed in the alkaline aqueous solution in order to promote development.

  In the method for producing a resist pattern of the present invention, if necessary, two or more kinds of development methods described above may be used in combination. Development methods include a dip method, a battle method, a spray method, a high-pressure spray method, brushing, and slapping, and the high-pressure spray method is most suitable for improving resolution.

[Preferred Embodiment of Permanent Mask Resist]
A preferred embodiment of a permanent mask resist using the photosensitive resin composition of the present invention will be described.

After the development step, it is preferable to perform ultraviolet irradiation or heating with a high-pressure mercury lamp for the purpose of improving solder heat resistance and chemical resistance. In the case of irradiating ultraviolet rays, the irradiation amount can be adjusted as necessary, and for example, irradiation can be performed at an irradiation amount of about 0.05 to 10 J / cm ² . Moreover, when heating a resist pattern, it is preferable to carry out for about 15 to 90 minutes in the range of about 130-200 degreeC.

  Both ultraviolet irradiation and heating may be performed. In this case, both may be performed at the same time, and after either one is performed, the other may be performed. When performing ultraviolet irradiation and heating simultaneously, it is preferable to heat to 60-150 degreeC from a viewpoint of providing solder heat resistance and chemical resistance more favorably.

  The permanent mask resist formed in this way also serves as a protective film for the wiring after soldering to the board, and has various characteristics of solder resist, for printed wiring boards, for semiconductor package boards, for flexible wiring boards It can be used as a solder resist.

  The solder resist is used, for example, as a plating resist or an etching resist when plating or etching a substrate, and is left on the substrate as it is to protect a wiring or the like (permanent mask resist). ).

  Further, in the above exposure step, when exposure is performed using a mask or drawing data having a pattern in which a predetermined portion of the conductor layer is unexposed, the unexposed portion is removed by developing this, and the substrate A resist having an opening pattern in which a part of the conductor layer formed thereon is exposed is obtained. Thereafter, it is preferable to perform a process necessary for forming the permanent mask resist.

  The substrate provided with the permanent mask resist is then mounted with a semiconductor element or the like (for example, wire bonding, C4 solder connection), and is mounted on an electronic device such as a personal computer.

  The present invention has been described in detail based on the embodiments. However, the present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.
(Examples 1-4, Comparative Examples 1-4)
The photosensitive resin composition solution was obtained by mixing each component shown in Table 1 with the compounding ratio (mass basis) of the solid content shown there.

In addition, each component in Table 1 is as follows.
Component (A-1): Polyurethane compound UXE-3044 (manufactured by Nippon Kayaku Co., Ltd., acid value 60 mgKOH / g, double bond equivalent 450 g / mol, weight average molecular weight 10,000)
The component (A-1) corresponds to the component (A).
Component (B-1): Methacrylic acid ester of ethylene oxide-modified bisphenol A (FA-321M, manufactured by Hitachi Chemical Co., Ltd.)
The component (B-1) corresponds to the component (B).
(C-1) Ingredient: Ciba Specialty Chemicals Co., Ltd., trade name I-907)
The component (C-1) corresponds to the component (C).
(D-1) component: Phosphinic acid salt (manufactured by Clariant Japan, trade name “EXOLIT OP 935”, phosphorus content = 23 mass%)
The component (D-1) corresponds to the component (D).
(E-1) Component: YDPF-1000S (manufactured by Toto Kasei Co., Ltd., glycidyl etherified product of phenol / formaldehyde polycondensate with epichlorohydrin, epoxy equivalent 423)
(E-2) Component: YDF-2001 (manufactured by Tohto Kasei Co., Ltd., glycidyl etherified product of epoxy formaldehyde polycondensate with epichlorohydrin, epoxy equivalent 417)
The above components (E-1) to (E-2) all correspond to the component (E).
Component (E-3): YDF-170 (manufactured by Tohto Kasei Co., Ltd., glycidyl etherified product of phenol / formaldehyde polycondensate with epichlorohydrin, epoxy equivalent 158)
(E-4) Component: NC-3000H (manufactured by Nippon Kayaku Co., Ltd., glycidyl etherified product of biphenyl skeleton-containing phenol compound with epichlorohydrin, epoxy equivalent 289)
(E-5) Component: YD-011 (manufactured by Toto Kasei Co., Ltd., glycidyl etherified product of bisphenol A skeleton-containing phenol compound with epichlorohydrin, epoxy equivalent 478)
The above components (E-3) to (E-5) are all glycidyl etherification products of epichlorohydrin of a phenol compound, but either the epoxy equivalent or the structure of the phenol compound is different, or both, the component (E) Not applicable.

注）表１中の値は、各成分の固形分の配合比である。また、表中記号「−」は、該当する成分を含有していないことを示す。

Note) The values in Table 1 are the blending ratio of the solid content of each component. Moreover, the symbol “-” in the table indicates that the corresponding component is not contained.

[Production of evaluation board and evaluation of release properties]
Each of the obtained photosensitive resin composition solutions was uniformly coated on a copper-clad laminate (manufactured by Nippon Steel Chemical Co., Ltd., Espanex MB series) to form a photosensitive resin composition layer. Printing is performed using a screen printing machine (SS1520, manufactured by Seritech Co., Ltd.) at a printing speed (squeegee running speed) of 200 mm / second and a screen plate (mesh 120, polyester material, printing area 110 mm square) and a copper-clad laminate. The gap (clearance) was 1 mm. The evaluation of the release property was evaluated as “◯” when the plate was released within 1 second after passing through the squeegee, and “X” when the release was required for one second or more. After printing, it was dried at 80 ° C. for about 20 minutes using a hot air convection dryer. The film thickness after drying of the photosensitive resin composition layer was 15 μm. The obtained substrate was used as an evaluation substrate.

[Evaluation of tack after drying]
The two photosensitive substrate formation surfaces after the above-mentioned drying were put together and overlapped, left flat and allowed to stand for 1 minute, and then the two substrates were separated. At this time, if a part of the photosensitive layer does not transfer to another substrate, it is evaluated as “◯” as no stickiness of the photosensitive layer, and if it is transferred to another substrate, it is evaluated as “×” as the stickiness of the photosensitive layer. did.

[Evaluation of light sensitivity]
A phototool having a stove 21-step tablet as a negative is brought into close contact with the obtained evaluation substrate, and development of the stove 21-step tablet is performed using an HMW-201GX type exposure machine manufactured by Oak Manufacturing Co., Ltd. After exposure with an energy amount that the remaining number of steps of the subsequent step was 8.0, development was carried out by spraying a 1% by mass aqueous sodium carbonate solution at 30 ° C. for 15 seconds, and heating (drying) at 80 ° C. for 10 minutes. The above energy amount was used as a numerical value for evaluating photosensitivity. The lower this value, the higher the photosensitivity. The results are shown in Table 2.

[Resolution evaluation]
A phototool having a stove 21-step tablet and a phototool having a wiring pattern with a line width / space width of 30/30 to 200/200 (unit: μm) as a negative for resolution evaluation are provided on the evaluation laminate. Using the exposure machine described above, the exposure was performed with an energy amount such that the number of remaining step stages after development of the stove 21-step tablet was 8.0, and then 15% 1% by weight aqueous sodium carbonate solution at 30 ° C. Development was carried out by spraying for 2 seconds, followed by heating and drying at 80 ° C. for 10 minutes. Here, the resolution was evaluated based on the smallest value (unit: μm) of the space width between the line widths in which a rectangular resist shape was obtained by development processing. It shows that it is excellent in the resolution, so that this value is small. The results are shown in Table 2.

[Production of evaluation FPC]
A photo tool having a stove 21-step tablet and a photo tool having a wiring pattern as a negative for evaluating the reliability of the coverlay are brought into close contact with each other on the evaluation substrate. After exposure with an energy amount such that the number of remaining steps after development of the stepped tablet is 8.0, spray development is performed under the same developer and development conditions as in the photosensitivity evaluation, and heating at 80 ° C. for 10 minutes. , Dried. Furthermore, the FPC for evaluation which formed the coverlay was obtained by heat-processing at 160 degreeC for 60 minute (s).

[Evaluation of folding resistance]
The evaluation FPC obtained as described above was repeatedly folded 180 ° by goblet folding, and the number of times until cracks in the coverlay were generated was observed with a microscope, and evaluated according to the following criteria. That is, if the coverlay is not cracked even if it is bent 5 times or more, it is “A”, and if the number of times until the crack is generated is 2 times or more and 5 times or less, it is “B”. Those having a number of times of 2 or less were evaluated as “C”. The results are shown in Table 2.

[Evaluation of flame retardancy]
A thin material vertical combustion test based on the UL94 standard was performed on the evaluation FPC described above. Evaluation was expressed as VTM-0 or VTM-1 based on the UL94 standard. The results are shown in Table 2. In Table 2, “combustion” indicates that the flame retardancy evaluation sample did not fall under VTM-0, VTM-1, or VTM-2 in the combustion test.

[Evaluation of warpage]
The evaluation FPC obtained as described above was cut into a certain size, and the warpage after being left on a hot plate at 260 ° C. for 60 seconds was evaluated. Those with a warp of 3 mm or less were evaluated as “A”, those with 3 to 10 mm as “B”, and those with a cylindrical shape as “C”. The results are shown in Table 2.

[Evaluation of resilience (stiffness)]
The evaluation FPC obtained as described above was evaluated for resilience (stiffness) using a Gurley-type stiffness tester. The smaller the value, the lower the rebound. The results are shown in Table 2.

"Evaluation of plating resistance"
The FPC for evaluation is subjected to electroless nickel plating (trade name Nimden NPR-4, manufactured by Uemura Kogyo Co., Ltd.) (15 minutes treatment), and further electroless gold plating (trade name, Goblite TAM-, manufactured by Uemura Kogyo Co., Ltd.). 54) (treatment for 10 minutes).

  For the evaluation substrate plated in this way, the plating solution soaked into the bottom of the cover lay, and the cover lay floating and peeling from the substrate were observed with a 100-fold metal microscope. evaluated. That is, the case where no penetration into the bottom of the cover lay was observed and the cover lay was not lifted or peeled was evaluated as “A”, and the case where any of them was recognized was evaluated as “C”. In addition, although a slight permeation to the bottom of the solder resist was recognized, there was no practical problem at all. The results are shown in Table 2.

"Evaluation of solder heat resistance"
Using the evaluation substrate having a cover lay obtained in the same manner as in the above “evaluation of plating resistance”, the solder heat resistance was evaluated as follows. That is, after applying a rosin flux (trade name MH-820V, manufactured by Tamura Kaken Co., Ltd., Tamura Seisakusho Co., Ltd.) to a substrate for evaluation, a soldering treatment in which the substrate is immersed in a solder bath at 288 ° C. for 10 seconds. went.
The crack occurrence state of the cover lay on the evaluation substrate subjected to the solder plating in this way, and the degree to which the cover lay was lifted and peeled off from the substrate were observed with a 100-fold metal microscope. The results were evaluated according to the following criteria. That is, the case where no crack of the coverlay was observed and the coverlay was neither lifted nor peeled was evaluated as “A”, and the case where any of them was recognized was evaluated as “B”. The results are shown in Table 2.

"Evaluation of HAST resistance"
Comb type with a line / space of 50 μm / 50 μm etched by etching the copper surface of a printed wiring board substrate (trade name MCL E-679, manufactured by Hitachi Chemical Co., Ltd.) with a 12 μm thick copper foil laminated on a glass epoxy substrate. Processed into electrodes. This was used as an evaluation wiring board.
A cover lay made of a cured resist was formed on the comb-shaped electrode of this evaluation wiring board in the same manner as in the above “evaluation of plating resistance”, and this was used as an evaluation substrate. This evaluation substrate was placed in a super accelerated high temperature and high humidity life test (HAST) bath under the conditions of 130 ° C., 85% RH, 6 V, and treated for 100 hours. After the test, the degree of migration in each evaluation substrate was observed with a 100-fold metal microscope and evaluated according to the following criteria. That is, “A” indicates that no significant migration has occurred in the coverlay, and “C” indicates that significant migration has occurred. The results are shown in Table 2. Migration is a phenomenon in which discoloration of the solder resist around the electrode and a decrease in insulation resistance occur when copper is eluted and deposited from the copper electrode to the solder resist.

"Evaluation of heat press resistance"
Using the evaluation substrate having a cover lay obtained in the same manner as the above “evaluation of plating resistance”, the hot press resistance was evaluated as follows. In other words, the evaluation substrate was hot pressed for 30 minutes at a pressure of 50 kgf / cm ² , a hot platen temperature of 200 ° C. using a hydraulic hot press apparatus. After completion of the press, the resist opening was observed and evaluated as “◯” when the resin exudation (bleeding) was not observed, and “×” when it was observed. The results are shown in Table 2.

ソルダーレジスト（特にフレキシブル基板用）としての適用に好ましくない結果は網掛けで示した。

Unfavorable results for application as a solder resist (especially for flexible substrates) are shown by shading.

  As is apparent from Table 2, the glycidyl etherification product containing the components (A) to (D), the thermosetting agent (E) and the phenol-formaldehyde polycondensate epichlorohydrin, and having an epoxy equivalent of 160 or more. According to the photosensitive resin compositions of Examples 1, 2, 3, and 4 using the thermosetting agent, it was confirmed that workability was good and sufficient photosensitivity and resolution were obtained. Moreover, the laminated board provided with the cured film formed from the photosensitive resin composition of Examples 1, 2, 3 and 4 has sufficient flame resistance (VTM-0), plating resistance, solder heat resistance, and HAST resistance. It was confirmed that Furthermore, it turned out that the cured film formed from the photosensitive resin composition of Example 1, 2, 3, and 4 has favorable low curvature and low resilience.

Claims (5)

(A) a polymer having a carboxyl group,
(B) a photopolymerizable compound having an ethylenically unsaturated bond,
(C) a photopolymerization initiator,
(D) a phosphorus-containing flame retardant,
(E) In the photosensitive resin composition containing a thermosetting agent, the (E) thermosetting agent is a glycidyl etherified product of epichlorohydrin of phenol / formaldehyde polycondensate and / or a derivative thereof, and an epoxy equivalent is The photosensitive resin composition which is 160 or more.   The (A) compound having a carboxyl group is (a) an epoxy acrylate compound having an ethylenically unsaturated group and two or more hydroxyl groups obtained by reacting a glycidyl compound with (meth) acrylic acid, and (b) The photosensitive resin composition according to claim 1, which is a reaction product of a diisocyanate compound and (c) a diol compound having a carboxyl group. The photosensitive resin composition of Claim 1 or 2 whose said (D) phosphorus containing flame retardant is the phosphinic acid salt shown by following General formula (1).

[In General Formula (1), A and B each independently represent a linear or branched alkyl group or aryl group having 1 to 6 carbon atoms, and M represents Mg, Ca, Al, Sb, Sn, Ge. , Ti, Zn, Fe, Zr, Ce, Bi, Sr, Mn, Li, Na, and K. At least one metal selected from the group consisting of K and m is an integer of 1 to 4. ]   The permanent mask resist which consists of a hardened | cured material of the photosensitive resin composition as described in any one of Claims 1-3. Providing a photosensitive layer comprising the photosensitive resin composition according to any one of claims 1 to 3 on a substrate;
Pattern irradiating the photosensitive layer with actinic rays;
Developing the photosensitive layer to form a permanent mask resist;
A method for producing a permanent mask resist.