JP5239786B2 - Photosensitive resin composition, photosensitive film using the same, resist pattern forming method, solder resist, interlayer insulating film, printed wiring board manufacturing method, and printed wiring board - Google Patents

Description

  The present invention relates to a photosensitive resin composition, a photosensitive film using the same, a resist pattern forming method, a solder resist, an interlayer insulating film, a printed wiring board manufacturing method, and a printed wiring board.

  As various electrical and electronic components become smaller, lighter, and more multifunctional, the semiconductor elements, semiconductor packages, printed wiring boards, flexible wiring boards, etc. that make them up are becoming denser and more precise and have fine openings. A photosensitive solder resist and an interlayer insulating film capable of forming a pattern are required.

  Photosensitive solder resists and interlayer insulating films that protect printed circuit boards are generally required to have characteristics such as developability, high resolution, insulation, heat resistance, and plating resistance. In particular, for solder resists for semiconductor package substrates, in addition to the above characteristics, for example, crack resistance against a temperature cycle test (TCT) of −65 to 150 ° C., and super accelerated high temperature between fine wirings. There is a demand for HAST resistance to a high humidity life test (HAST).

  On the other hand, when a multilayer wiring is formed by a photo via, surface roughening is performed in order to improve adhesion with the plated copper. Therefore, in addition to the above-described characteristics, the interlayer insulating film is also required to have desmear resistance when performing surface roughening (desmear) treatment.

  For the photosensitive solder resist and interlayer insulating film, a photosensitive resin composition as a raw material is applied on the substrate, or a pre-formed photosensitive resin composition layer is laminated on the substrate, and after exposure, developed. It is produced by forming an image.

  In order to increase the resolution of these photosensitive resin compositions, it is necessary to increase the solubility of the unexposed portion in the developer, that is, to improve the contrast. In order to increase the solubility of the unexposed area, there is a method of introducing a hydrophilic group into the polymer in the photosensitive resin composition. When a carboxyl group is applied as such a hydrophilic group, the degree of hydrophilicity is represented by an acid value, and the higher the acid value resin, the higher the solubility in a developer.

  In recent years, an alkali development type using a dilute alkaline aqueous solution as a developing solution has become mainstream in consideration of environmental problems. In order to perform this alkali development, it is necessary to further increase the acid value of the polymer as compared with the case of using an organic solvent-added developer.

  However, in the case of a photosensitive insulating material such as a solder resist or an interlayer insulating film, the higher the acid value of the polymer, the higher the water absorption rate. Therefore, the insulation resistance (HAST resistance) decreases under high temperature and high humidity conditions. Deterioration in solderability (solder heat resistance or crack resistance) is likely to occur.

  Therefore, in order to ensure high-temperature and high-humidity resistance, a liquid resist ink composition using a reaction product of a novolac type epoxy resin and an unsaturated carboxylic acid has been developed (see, for example, Patent Document 1).

  By the way, the photosensitive resin composition used for the solder resist or the interlayer insulating film is usually in a liquid form. Since the carboxyl group easily reacts with the epoxy group at room temperature, the liquid photosensitive resin composition includes a curable epoxy resin and a photosensitive prepolymer containing a carboxylic acid group for imparting alkali developability. A two-part type divided into two is generally used.

  However, the two-pack type photosensitive resin composition has a short storage stability (pot life) after mixing two liquids, from several hours to one day, so it must be mixed immediately before use. Limits arise.

  On the other hand, in recent years, dry film type solder resists and interlayer insulating films have attracted attention from the viewpoint of improving film thickness uniformity, surface smoothness, thin film formability, and handleability. When the photosensitive resin composition was mixed in advance to form a dry film, the storage stability of the film was poor, and storage in the film state was difficult.

  As a one-part type photosensitive resin composition in which such problems are unlikely to occur, light obtained by reacting a reaction product of a novolak type epoxy resin and an unsaturated monobasic acid with an alicyclic dibasic acid anhydride A one-component liquid photo solder resist ink composition composed of a thermosetting accelerator such as a curable resin, a photopolymerization initiator, a diluent, and a vinyl triazine compound has been proposed (see, for example, Patent Document 2). Further, a photosensitive resin composition comprising a blocked isocyanate compound, a carboxyl group-containing prepolymer, a photopolymerization initiator, a diluent and an adhesion-imparting agent has been proposed as a thermosetting agent instead of an epoxy resin (for example, Patent Documents). 3).

  In addition, as a dry film type solder resist, a photosensitive resin having excellent storage stability, which is difficult to achieve with the conventional two-component type photosensitive resin composition, capable of alkali development, and excellent in chemical resistance, heat resistance, etc. A composition has been developed (see, for example, Patent Document 4).

JP-A 61-243869 JP-A-4-281454 JP 2001-305726 A JP 2005-316431 A

  However, the conventional photosensitive resin compositions described in Patent Documents 2 and 3 have insufficient insulation reliability such as heat resistance, crack resistance, and HAST resistance of the cured film.

  In addition, the solder resist obtained from the conventional film type photosensitive resin composition has insufficient physical properties that require heat resistance such as a temperature cycle test, and is inferior in crack resistance compared to a liquid type solder resist. There was a problem.

  Further, when a multilayer wiring is formed using the above-described conventional alkali development type photosensitive resin composition, it remains in the alkali-soluble polymer in a swelling process in which it is swollen with a concentrated alkali solution when performing a surface roughening (desmear) treatment. Since the cured carboxylic acid reacts and the cured film is attacked, the cured film is decomposed and peeled off in the subsequent immersion step of immersing in the permanganate solution, and a good interlayer insulating film cannot be obtained. there were.

  Therefore, the present invention has good storage stability when made into a film or a one-pack type resin composition, and has excellent developability, resolution, insulation, heat resistance, plating resistance, crack resistance, and HAST resistance. Provided are a photosensitive resin composition capable of forming a solder resist or an interlayer insulating film, a photosensitive element using the same, a method for forming a resist pattern, a solder resist, an interlayer insulating film, a method for manufacturing a printed wiring board, and a printed wiring board. For the purpose.

  In order to solve the above problems, the present invention provides (A) a polymer having a carboxyl group, (B) a photopolymerizable compound having an ethylenically unsaturated bond, (C) a photopolymerization initiator, and (D) an epoxy. A photosensitive resin composition containing a resin-encapsulated microcapsule is provided.

  The photosensitive resin composition of this invention is excellent in the storage stability when it is set as a film or a one-pack type resin composition by having the said structure. Furthermore, it is excellent in various properties such as resolution, insulation, heat resistance, plating resistance, crack resistance, HAST resistance, and desmear resistance, and a good solder resist or interlayer insulating film can be formed.

  The reason why this effect is achieved is not necessarily clear, but the present inventors speculate as follows. That is, by using an epoxy resin-encapsulated microcapsule as a thermal crosslinking component, the epoxy group does not react with the carboxyl group and becomes stable at room temperature, reacts efficiently with the carboxylic acid by heating, and finally has a low carboxylic acid content. This is probably because a crosslinked structure can be formed.

  The average particle diameter of the (D) epoxy resin-encapsulated microcapsules is preferably 10 nm to 10 μm. According to the photosensitive resin composition having the above configuration, the resolution can be further improved, and a solder resist or an interlayer insulating film having a fine opening pattern can be formed.

  The (D) epoxy resin-encapsulated microcapsule has a core material made of an epoxy resin and a hollow spherical wall material that encloses the core material, and the wall material is destroyed by heating at 120 to 180 ° C. It is preferable that Moreover, it is preferable that the said wall material is a wall material which consists of 1 type, or 2 or more types of resin selected from a polyurethane, a polyurea, a polystyrene, and a urea resin. The photosensitive resin composition having the above structure is not only more excellent in storage stability when it is made into a film or a one-component resin composition, but also has resolution, insulation, heat resistance, plating resistance, crack resistance, It is possible to form a solder resist or an interlayer insulating film that is more excellent in various properties such as HAST resistance and desmear resistance.

  The acid value of the polymer (A) having a carboxyl group is preferably 30 to 110 mgKOH / g. The photosensitive resin composition having the above configuration is further excellent in developability and resolution. Moreover, according to such a photosensitive resin composition, it becomes possible to form efficiently the solder resist or interlayer insulation film which has a fine opening pattern.

  The (A) polymer having a carboxyl group preferably contains (a1) a polymerizable compound having a carboxyl group and an ethylenically unsaturated bond.

  Moreover, this invention provides a photosensitive film provided with a support body and the photosensitive layer which consists of the said photosensitive resin composition formed on this support body.

  The present invention also includes a lamination step of laminating a photosensitive layer made of the photosensitive resin composition on a substrate, an exposure step of irradiating a predetermined portion of the photosensitive layer with actinic rays to photocure an exposed portion, And a developing step for removing a portion other than the exposed portion of the photosensitive layer.

  The present invention also includes a lamination step of laminating a photosensitive layer made of the photosensitive resin composition on a substrate, an exposure step of irradiating a predetermined portion of the photosensitive layer with actinic rays to photocure an exposed portion, Provided is a resist pattern forming method comprising: a developing step for removing portions other than the exposed portion of the photosensitive layer; and a post-heating step for further thermosetting the exposed portion of the photosensitive layer.

  Moreover, this invention provides the soldering resist which consists of hardened | cured material of the said photosensitive resin composition formed on the board | substrate.

  Moreover, this invention provides the interlayer insulation film which consists of a hardened | cured material of the said photosensitive resin composition formed on the board | substrate.

  Moreover, this invention provides the manufacturing method of a printed wiring board which plates the board | substrate with which the resist pattern was formed by the formation method of the said resist pattern.

  Moreover, this invention provides the manufacturing method of a printed wiring board which roughens the surface of the board | substrate with which the resist pattern was formed by the said formation method of a resist pattern, and plated the roughened board | substrate and / or resist pattern.

  Moreover, this invention provides a printed wiring board provided with a board | substrate and the hardened | cured material of the said photosensitive resin composition formed on this board | substrate.

  According to the present invention, the storage stability is good when a film or a one-pack type resin composition is used, and the developability, resolution, insulation, heat resistance, plating resistance, crack resistance, and HAST resistance are excellent. The photosensitive resin composition which can form a soldering resist, the photosensitive element using the same, the formation method of a resist pattern, a soldering resist, the manufacturing method of a printed wiring board, and a printed wiring board can be provided.

  In addition, according to the present invention, the interlayer insulation has good storage stability when made into a film or a one-component resin composition, and has excellent developability, resolution, insulation, heat resistance, plating resistance, and desmear resistance. A photosensitive resin composition capable of forming a film, a photosensitive element using the same, a resist pattern forming method, an interlayer insulating film, a printed wiring board manufacturing method, and a printed wiring board can be provided.

  Furthermore, according to the present invention, since the photosensitive resin composition can be formed into a film, the process can be shortened and both sides of the insulating layer can be formed, so that the productivity of the printed wiring board can be improved.

  In the following, preferred embodiments of the present invention will be described with reference to the drawings. Note that the same reference numerals are used for the same elements in the drawings, and redundant description is omitted. In the present invention, (meth) acrylic acid means acrylic acid or methacrylic acid, (meth) acrylate means acrylate or the corresponding methacrylate, and (meth) acryloyl group means acryloyl group or methacryloyl group. means.

  The photosensitive resin composition according to this embodiment includes (A) a polymer having a carboxyl group, (B) a photopolymerizable compound having an ethylenically unsaturated bond, (C) a photopolymerization initiator, and (D). And epoxy resin-encapsulated microcapsules.

  Examples of the polymer (A) having a carboxyl group (hereinafter sometimes referred to as “component (A)”) include, for example, acrylic resin, polyurethane, vinyl group-containing epoxy resin, epoxy resin, phenoxy resin, polyester, polyamide. , Polyimides, polyamideimides, polyesterimides, polycarbonates, melamine resins, polyphenylene sulfide, polyoxybenzoyl, and other known resins and acid-modified resins thereof having a carboxyl group in the molecule. These can be used alone or in combination of two or more.

  Component (A) is a polymerizable compound having a carboxyl group and an ethylenically unsaturated bond (hereinafter referred to as “a1”) from the viewpoint of further improving various properties such as insulation, heat resistance, plating resistance and crack resistance of the cured film. In some cases, it is also preferable to include “(a1) component”).

  In addition, from the viewpoint of further improving developability, the component (A) is a vinyl copolymer compound containing (a2) (meth) acrylic acid and / or (meth) acrylic acid alkyl ester as a copolymerization component (hereinafter referred to as a case). It is also preferable to contain “(a2) component”.

  (A1) component and (a2) component can be used individually by 1 type or in combination of 2 or more types. Hereinafter, the component (a1) and the component (a2) will be described.

  The component (a1) is not particularly limited as long as it is a polymerizable compound having a carboxyl group and an ethylenically unsaturated bond in the molecule. For example, an ester compound of an epoxy compound and an unsaturated monocarboxylic acid may be a polybasic acid. An addition reaction product obtained by adding an anhydride (that is, an addition reaction product obtained by reacting a hydroxyl group-containing compound, which is a reaction product of an epoxy compound and an unsaturated monocarboxylic acid, with a polybasic acid anhydride).

  Here, examples of the epoxy compound include a bisphenol type epoxy compound obtained by reacting bisphenol A type or bisphenol F type with epichlorohydrin. Examples of the bisphenol type epoxy compound include bisphenol A type, bisphenol F type, hydrogenated bisphenol A type, amino group-containing, alicyclic type, etc., such as GY-260, GY-255, and XB-2615 manufactured by Ciba Geigy Epoxy compounds such as polybutadiene modified are preferably used.

  In addition, as the epoxy compound, a novolak obtained by reacting at least one selected from the group consisting of phenol, cresol, halogenated phenol and alkylphenol with formaldehyde in the presence of an acidic catalyst is reacted with epichlorohydrin. The novolak type epoxy compound obtained by making it contain is mentioned. Examples of the novolac epoxy resin include YDCN-701, YDCN-704, YDPN-638 and YDPN-602 manufactured by Tohto Kasei Co., Ltd., DEN-431 and DEN-439 manufactured by Dow Chemical Company, and EPN- manufactured by Ciba-Gigi Company. 1299, N-730, N-770, N-865, N-665, N-673, VH-4150 and VH-4240 manufactured by Dainippon Ink & Chemicals, Inc. EOCN-120 and BREN manufactured by Nippon Kayaku Co., Ltd. Can be mentioned.

  Further, as the epoxy compound, for example, a salicylaldehyde-phenol type or cresol type epoxy compound (EPPN502H, FAE2500, etc., manufactured by Nippon Kayaku Co., Ltd.) can be suitably used.

  Examples of the epoxy compound include Epicoat 828, Epicoat 1007 and Epicoat 807 manufactured by Japan Epoxy Resin Co., Ltd., Epicron 840, Epicron 860 and Epicron 3050 manufactured by Dainippon Ink and Chemicals, DER-330 manufactured by Dow Chemical Co., and DER. -337 and DER-361, Daicel Chemical Industries' Celoxide 2021, Mitsubishi Gas Chemical's TETRAD-X and TETRAD-C, Nippon Soda Co., Ltd. EPB-13 and EPB-27, etc. can be used. Furthermore, a mixture or block copolymer of the above-described epoxy compounds can also be used.

  The unsaturated monocarboxylic acid is not particularly limited as long as it is a compound having one carboxyl group in the molecule and one or more ethylenically unsaturated bonds. For example, (meth) acrylic acid, croton Acid, cinnamic acid, and derivatives thereof. Further, for example, (i) a reaction product of (meth) acrylates having one hydroxyl group in one molecule and a polybasic acid anhydride, (ii) a reaction between a dibasic acid and an unsaturated monoglycidyl compound. A reaction product of a partial ester compound and a polybasic acid anhydride, (iii) a reaction product of a (meth) acrylate having one hydroxyl group in one molecule and a dibasic acid, and the like are also preferably used. be able to.

  Specific examples of the unsaturated monocarboxylic acid include saturated or unsaturated dibasic acids such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid and succinic acid, hydroxyethyl (meth) acrylate, A reaction product obtained by reacting unsaturated monoglycidyl compounds such as hydroxypropyl (meth) acrylate, tris (hydroxyethyl) isocyanurate di (meth) acrylate and glycidyl (meth) acrylate in an equimolar ratio by a conventional method Can be mentioned. These unsaturated monocarboxylic acids can be used alone or in admixture of two or more. As the unsaturated monocarboxylic acid, acrylic acid is preferable.

  As the polybasic acid anhydride, a saturated or unsaturated polybasic acid anhydride can be used, for example, anhydrous phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, succinic acid, trimellitic acid, etc. Things.

  Examples of the component (a1) include ZAR-1035, AFR-1158, CCR-1171H, and PCR-1050 (all are trade names) manufactured by Nippon Kayaku Co., Ltd.

  In addition, as the component (a1), for example, a polyurethane compound obtained by reacting an epoxy acrylate compound having two or more hydroxyl groups and an ethylenically unsaturated bond, a diisocyanate compound, and a diol compound having a carboxyl group Can also be suitably used. When the component (a1) is such a polyurethane compound, it is preferable from the viewpoint of increasing the sensitivity of the photosensitive resin composition.

  Examples of the polyurethane compound include UXE-3011, UXE-3012, and UXE-3024 (manufactured by Nippon Kayaku Co., Ltd., trade names). Moreover, as said polyurethane compound, the polyurethane compound which has a structure represented by following General formula (1) is mentioned, for example.

In the general formula (1), R ¹¹ represents an epoxy acrylate residue, R ¹² represents a diisocyanate residue, R ¹³ represents an alkyl group having 1 to 5 carbon atoms, and R ¹⁴ represents a hydrogen atom or a methyl group. 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. In addition, a plurality of groups in the formula may be the same or different.

  As said polyurethane compound, what has a bisphenol A type structure as a hard segment part formed from the epoxy acrylate compound which has a 2 or more hydroxyl group and ethylenically unsaturated group is preferable.

  As described above, the polyurethane compound is an epoxy acrylate compound having two or more hydroxyl groups and an ethylenically unsaturated group (hereinafter referred to as “raw material epoxy acrylate”), a diisocyanate compound (hereinafter referred to as “raw material diisocyanate”), and It is a compound obtained using a diol compound having a carboxyl group (hereinafter referred to as “raw diol”) as a raw material component. First, these raw material components will be described.

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

  As the raw material diisocyanate, any compound having two isocyanato groups can be used without particular limitation. For example, phenylene diisocyanate, tolylene diisocyanate, xylylene diisocyanate, tetramethyl xylylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, tolden 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 can be mentioned. As a diisocyanate compound, it can apply individually by 1 type or in combination of 2 or more types.

  The raw material diol is a compound having two hydroxyl groups such as alcoholic hydroxyl group and phenolic hydroxyl group in the molecule, and also having a carboxyl group. The hydroxyl group preferably has an alcoholic hydroxyl group from the viewpoint of improving the developability of the photosensitive resin composition with an alkaline aqueous solution. Examples of such diol compounds include dimethylolpropionic acid and dimethylolbutanoic acid.

  The component (a1) preferably has a weight average molecular weight of 2000 to 50000, more preferably 3000 to 30000, from the viewpoint of further improving various properties such as insulation, heat resistance, plating resistance and crack resistance. Preferably, it is 3000-20000.

  The component (a2) is not particularly limited as long as it is a vinyl copolymer compound containing (meth) acrylic acid and / or (meth) acrylic acid alkyl ester as a copolymerization component. For example, (meth) acrylic acid and ( Examples thereof include vinyl copolymer compounds obtained by radical polymerization using a meta) acrylic acid alkyl ester or the like 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.

  (A2) As a component, 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, esters of vinyl alcohol such as acrylonitrile and vinyl-n-butyl ether, (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acrylic acid dimethylaminoethyl 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 Acid anhydride, monomethyl maleate, Maleic acid monomers such as monoethyl laneate and monoisopropyl maleate, fumaric acid, cinnamic acid, α-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid, styrene, α-methylstyrene and vinyltoluene And styrene derivatives. 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 and a (meth) acrylic-acid alkylester can also be used conveniently. Such an ethylenically unsaturated bond can be introduced into the side chain and / or the terminal via an ester bond, a urethane bond or the like. As such a method, for example, a carboxyl group of a vinyl monomer copolymer that can be copolymerized with the above (meth) acrylic acid and (meth) acrylic acid alkyl ester is reacted with a glycidyl group-containing ethylenic vinyl monomer to form an ester bond. The method of forming is mentioned.

  The component (a2) has a weight average molecular weight of preferably 5,000 to 150,000, more preferably 20,000 to 100,000, and further preferably 30,000 to 80,000 from the viewpoint of improving developability. When the weight average molecular weight is less than 5,000, the developer resistance tends to decrease, and when it exceeds 150,000, the development time tends to be longer.

  The acid value of the component (A) is preferably 30 to 110 mgKOH / g from the viewpoint of improving the alkali developability and resolution and various properties such as high-temperature and high-humidity resistance of the cured film in a balanced manner. More preferably, it is -100 mgKOH / g, and it is further more preferable that it is 40-90 mgKOH / g.

Here, the acid value can be measured as follows. That is, first, 1 g of the component for measuring the acid value is precisely weighed, then 30 g of acetone is added and uniformly dissolved to obtain a measurement 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. And an acid value is computed by following Formula.
A = 10 × Vf × 56.1 / (Wp × I)

  In the formula, A represents the acid value (mgKOH / g), Vf represents the titration amount (mL) of the KOH aqueous solution, Wp represents the weight (g) of the measured measurement solution, and I represents the non-volatile content in the measurement solution. The ratio (mass%) is shown.

  The content of the component (A) is the total amount (solid content) of the component (A) and the component (B) from the viewpoint of improving various properties such as sensitivity and coating film formability and heat resistance of the cured film in a balanced manner. It is preferable to set it as 20-90 mass parts with respect to a mass part, It is more preferable to set it as 30-80 mass parts, It is further more preferable to set it as 40-70 mass parts.

  The (B) photopolymerizable compound having an ethylenically unsaturated bond (hereinafter sometimes referred to as “component (B)”) is a compound having one or more ethylenically unsaturated bonds in the molecule. If there is no particular limitation, for example, a bisphenol A (meth) acrylate compound, a compound obtained by reacting a polyhydric alcohol with an α, β-unsaturated carboxylic acid, a glycidyl group-containing compound with an α, β-unsaturated carboxylic acid Examples thereof include a compound obtained by reacting an acid, a urethane monomer such as a (meth) acrylate compound having a urethane bond in the molecule, or a urethane oligomer. Besides these, nonylphenoxy polyoxyethylene acrylate, γ-chloro-β-hydroxypropyl-β ′-(meth) acryloyloxyethyl-o-phthalate, β-hydroxyalkyl-β ′-(meth) acryloyloxy Examples thereof include phthalic acid compounds such as alkyl-o-phthalate, (meth) acrylic acid alkyl esters, and EO-modified nonylphenyl (meth) acrylate. These may be used alone or in combination of two or more.

  The component (B) preferably contains a bisphenol A (meth) acrylate compound from the viewpoint of improving alkali developability. 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. Is mentioned.

  The component (B) preferably contains a bisphenol A-based (meth) acrylate compound from the viewpoint of improving sensitivity and resolution, and 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) More preferably, propane is included.

  Examples of 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane include 2,2-bis (4-((meth) acryloxydiethoxy) phenyl) propane, 2,2- Bis (4-((meth) acryloxytriethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytetraethoxy) phenyl) propane, 2,2-bis (4-((meth)) Acryloxypentaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyhexaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyheptaethoxy) phenyl) propane 2,2-bis (4-((meth) acryloxyoctaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxy nonaethoxy) ) Phenyl) propane, 2,2-bis (4-((meth) acryloxydecaethoxy) phenyl), 2,2-bis (4-((meth) acryloxyundecaethoxy) phenyl), 2,2- Bis (4-((meth) acryloxydodecaethoxy) phenyl), 2,2-bis (4-((meth) acryloxytridecaethoxy) phenyl), 2,2-bis (4-((meth) acrylic) Loxytetradecaethoxy) phenyl), 2,2-bis (4-((meth) acryloxypentadecaethoxy) phenyl), and 2,2-bis (4-((meth) acryloxyhexadecaethoxy) phenyl) Etc. You may use these individually or in combination of 2 or more types.

  Among the above compounds, 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane is FA-321M (trade name, manufactured by Hitachi Chemical Co., Ltd.) or BPE-500 (Shin Nakamura Chemical Co., Ltd.). ), Commercially available as trade name), and 2,2-bis (4- (methacryloxypentadecaethoxy) phenyl) is BPE-1300 (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.) It is commercially available.

  Examples of 2,2-bis (4-((meth) acryloxypolypropoxy) phenyl) propane include 2,2-bis (4-((meth) acryloxydipropoxy) phenyl) propane, 2, 2-bis (4-((meth) acryloxytripropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytetrapropoxy) phenyl) propane, 2,2-bis (4-(( (Meth) acryloxypentapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyhexapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxyheptapropoxy) phenyl ) Propane, 2,2-bis (4-((meth) acryloxyoctapropoxy) phenyl) propane, 2,2-bis (4-((meth)) Acryloxynonapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxydecapropoxy) phenyl), 2,2-bis (4-((meth) acryloxyundecapropoxy) phenyl), 2,2-bis (4-((meth) acryloxydodecapropoxy) phenyl), 2,2-bis (4-((meth) acryloxytridecapropoxy) phenyl), 2,2-bis (4- ( (Meth) acryloxytetradecapropoxy) phenyl), 2,2-bis (4-((meth) acryloxypentadecapropoxy) phenyl), and 2,2-bis (4-((meth) acryloxyhexadeca) Propoxy) phenyl) and the like. These may be used alone or in combination of two or more.

  Examples of 2,2-bis (4-((meth) acryloxypolyethoxypolypropoxy) phenyl) propane include 2,2-bis (4-((meth) acryloxydiethoxyoctapropoxy) phenyl) propane, Examples include 2,2-bis (4-((meth) acryloxytetraethoxytetrapropoxy) phenyl) propane and 2,2-bis (4-((meth) acryloxyhexaethoxyhexapropoxy) phenyl) propane. . These can be used alone or in combination of two or more.

  Examples of the compound obtained by reacting a polyhydric alcohol with an α, β-unsaturated carboxylic acid include, for example, polyethylene glycol di (meth) acrylate having 2 to 14 ethylene groups and 2 to 14 propylene groups. Polypropylene glycol di (meth) acrylate, polyethylene polypropylene glycol di (meth) acrylate having 2 to 14 ethylene groups and 2 to 14 propylene groups, trimethylolpropane di (meth) acrylate, tri Methylolpropane tri (meth) acrylate, EO-modified trimethylolpropane tri (meth) acrylate, PO-modified trimethylolpropane tri (meth) acrylate, EO / PO-modified trimethylolpropane tri (meth) acrylate, tetramethylolmethanetri (meth) A Examples thereof include acrylate, tetramethylolmethane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate. These may be used alone or in combination of two or more.

“EO” refers to “ethylene oxide”, and “PO” refers to “propylene oxide”. Further, “EO modified” means having a block structure of ethylene oxide units (—CH ₂ —CH ₂ —O—), and “PO modified” means propylene oxide units (—CH ₂ —CH ₂ —CH _{2). -O -, - CH 2 (CH} 3) means having a block structure of CH 2 -O-).

  Examples of the compound obtained by reacting a glycidyl group-containing compound with an α, β-unsaturated carboxylic acid include trimethylolpropane triglycidyl ether tri (meth) acrylate and 2,2-bis (4- (meth) acryloxy- 2-hydroxy-propyloxy) phenyl and the like. Examples of the α, β-unsaturated carboxylic acid for obtaining the above compound include (meth) acrylic acid.

  Examples of urethane monomers having a urethane bond in the molecule include (meth) acrylic monomers having an OH group at the β-position, isophorone diisocyanate, 2,6-toluene diisocyanate, 2,4-toluene diisocyanate, and 1, 6-Hexamethylene diisocyanate and other diisocyanate compounds, addition reaction products, tris ((meth) acryloxytetraethylene glycol isocyanate) hexamethylene isocyanurate and other (meth) acrylate compounds having an isocyanurate skeleton, EO-modified urethane di (Meth) acrylate, EO or PO-modified urethane di (meth) acrylate, and the like.

The component (B) contains a (meth) acrylate compound having a urethane bond and an isocyanurate skeleton in the molecule from the viewpoint of improving various properties such as heat resistance after curing of the photosensitive resin composition and resistance to high temperature and high humidity. It is preferable.

  Furthermore, examples of the (meth) acrylic acid alkyl ester include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid butyl ester, and (meth) acrylic acid 2-ethylhexyl ester. Can be mentioned. These (B) components can be used individually by 1 type or in combination of 2 or more types.

  The content of the component (B) is a total amount (solid content) of the component (A) and the component (B) from the viewpoint of improving various characteristics such as sensitivity and coating film formability and heat resistance of the cured film in a balanced manner. It is preferable to set it as 10-80 mass parts with respect to a mass part, It is more preferable to set it as 20-70 mass parts, It is further more preferable to set it as 30-60 mass parts.

  In the photosensitive resin composition of the present invention, the total number of moles of ethylenically unsaturated bonds in the component (A) and the component (B) is 100 g based on the total amount of the component (A) and the component (B). 0.05 to 0.3 mol, more preferably 0.07 to 0.23 mol, and even more preferably 0.16 to 0.23. When the total number of moles of ethylenically unsaturated bonds is less than 0.05 mole, the sensitivity of the photosensitive resin composition is lowered, and the crosslinking density after curing is lowered, so that the coating film surface is whitened under high temperature and high humidity, Further, the resist swells and swelling is likely to occur. On the other hand, when it exceeds 0.3 mol, the stress generated at the interface between copper and resist on the wiring board during photocuring increases, and when the stress is released under high temperature and high humidity, at the interface between copper and resist. Swelling is likely to occur.

  The total number of moles of ethylenically unsaturated bonds is the product of the number of moles of ethylenically unsaturated bonds per unit mass of component (A) (mol / g) and the content (g), and the unit mass of component (B). It can be determined by the total amount of the product of the number of moles of ethylenically unsaturated bonds per mole (mol / g) and the content (g).

  As the above (C) photopolymerization initiator (hereinafter, may be referred to as “(C) component”), one that matches the wavelength of the light source at the time of exposure may be used, and a known one may be used. Can do. Examples of such a photopolymerization initiator include acetophenone, benzophenone, 4,4′-bis (dimethylamino) benzophenone (Michler ketone), 4,4′-bis (diethylamino) benzophenone, 4-methoxy-4′-dimethyl. Aminobenzophenone, 2-benzyl-2-dimethylamino-1-morpholinophenyl) -butanone-1, 2-ethylanthraquinone, aromatic ketones such as phenanthrenequinone, quinones such as alkylanthraquinone, benzoin methyl ether, benzoin ethyl ether Benzoin ether such as benzoin phenyl ether, benzoin such as methyl benzoin and ethyl benzoin, benzyl derivatives such as benzyl dimethyl ketal, 9-phenylacridine, 1,7-bis (9,9′-acridini ) Acridine derivatives such as heptane, N- phenylglycine, N- phenylglycine derivatives, coumarin-based compounds. These can be used individually by 1 type or in combination of 2 or more types.

  The content of component (C) is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the total solid content in the photosensitive resin composition from the viewpoint of photosensitivity, It is more preferable to set it as -8 mass parts, and it is still more preferable to set it as 1-5 mass parts.

  As the above-mentioned (D) epoxy resin-encapsulated microcapsules (hereinafter sometimes referred to as “(D) component”), an epoxy resin that is a core material (core) and a wall material (shell) that surrounds it so as to confine it The microcapsule comprised from these is mentioned.

  As component (D), for example, liquid or solid epoxy resin such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, biphenyl type epoxy resin, phenol novolac type epoxy resin, etc. is encapsulated by a known encapsulation method. Can be used. These may be used alone or in combination of two or more.

  Examples of the encapsulation method include chemical methods such as interfacial polymerization method and in-situ polymerization method, physicochemical methods such as coacervation method and submerged drying method, mechanical methods such as mechanofusion and mechanochemical, In addition, the spray drying method, the impact method in high-speed air current, etc. are mentioned.

  The wall material of component (D) is preferably one that is stable at room temperature and that can be broken by heating at 120 to 180 ° C. to release the contained epoxy resin, and is melted or decomposed by heating at the above temperature, etc. A wall material made of is preferable. Examples of such a resin include polyurethane, polyurea, polystyrene, urea resin, and the like.

  (D) Although the average particle diameter of a component can select what was suitable according to the use of the photosensitive resin composition and the film thickness of a coating film, it is 10 nm-10 micrometers from a viewpoint of improving a resolution more. It is preferably 20 nm to 5 μm, more preferably 40 nm to 3 μm, and particularly preferably 50 nm to 1 μm. If the particle diameter is less than 10 nm, it is difficult to produce microcapsules, and if it exceeds 10 μm, the resolution of the photosensitive resin composition tends to be lowered.

  Here, the average particle diameter indicates the value of the median diameter (D50) measured by diluting the microcapsule dispersion with deionized water and using a particle size distribution measuring device (Malvern Instruments Ltd., Zeta Sizer 3000HSa). .

  In addition, the epoxy resin encapsulation rate of component (D) (content of epoxy resin relative to the mass of component (D)) is preferably 30 to 99% by mass from the viewpoints of reactivity and thermal stability. More preferably, it is -90 mass%, and it is further more preferable that it is 50-80 mass%.

Here, the epoxy resin encapsulation rate refers to crushing the epoxy resin-encapsulated microcapsules, weighing this, washing with a good solvent of an epoxy resin composed of MEK, etc., and then measuring the mass of the remaining wall material after drying, The value obtained from the following formula is shown.
{1- (mass of wall material) / (mass of epoxy resin-encapsulated microcapsule)} × 100 (mass%)

In addition, the thickness (T) of the wall material of component (D) is a range represented by the following formula from the viewpoint of the storage stability of the microcapsules and the progress of the thermosetting reaction (easy to break the wall material). It is preferable that In the following formula, φ represents the particle diameter of the component (D).
0.001 × φ ≦ T ≦ 0.3 × φ

  The component (D) can be used in various forms of use. For example, the component (D) may be used in a solid form, or may be used in a liquid or emulsion form dispersed in various solvents. When used as a dispersion such as an emulsion, a dispersant may be added to the photosensitive resin composition for the purpose of preventing aggregation of the microcapsules.

  The content of the component (D) is 0 with respect to the total solid content in the photosensitive resin composition from the viewpoint of improving various properties such as insulation, heat resistance, plating resistance, and crack resistance of the cured film. It is preferably 5 to 50% by mass, more preferably 1 to 40% by mass, and further preferably 3 to 30% by mass.

  The photosensitive resin composition according to the present embodiment is added with (E) a thermosetting agent (hereinafter, may be referred to as “(E) component”) as long as the effects exhibited by the above configuration are not impaired. Also good.

  As the component (E), for example, a thermosetting agent that crosslinks itself by heating, that is, a curing agent that forms a polymer network structure by applying heat, or reacts with the carboxyl group of the component (A) by heating. Examples thereof include a curing agent that forms a three-dimensional structure.

  Examples of the thermosetting agent that itself crosslinks by heating include a bismaleimide compound.

  Examples of the bismaleimide compound include 1,6-bis (N-malemidyl) -2,2,4-trimethylhexane, m-di-N-malemidylbenzene, and bis (4-N-malemidylphenyl). ) Methane, 2,2-bis (4-N-maleimidylphenyl) propane, 2,2-bis (4-N-maleimidyl 2,5-dibromophenyl) propane, 2,2-bis [(4-N Examples thereof include various bismaleimide compounds such as -malemidylphenoxy) phenyl] propane and 2,2-bis [(4-N-malemidyl-2-methyl-5-ethylphenyl) propane. These bismaleimide compounds may be used alone or as a modified product with various resins. Among these, a bismaleimide compound having an aromatic ring is preferable from the viewpoint of heat resistance of the cured film. These can be used individually by 1 type or in combination of 2 or more types.

  Moreover, as a hardening | curing agent which reacts with the carboxyl group of (A) component by heating and forms a three-dimensional structure, a block isocyanate compound is mentioned, for example.

  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. These can be used individually by 1 type or in combination of 2 or more types. Examples of the polyisocyanate compound to be blocked include 4,4-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene 1,5-diisocyanate, o-xylene diisocyanate, m-xylene diisocyanate, Aromatic polyisocyanates such as 2,4-tolylene dimer, 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. These can be used individually by 1 type or in combination of 2 or more types.

  When the photosensitive resin composition contains the component (E), the content is from the viewpoint of improving various properties such as insulation, heat resistance, plating resistance, and crack resistance of the cured film. It is preferable that it is 1-50 mass parts with respect to 100 mass parts of total solid content in it, It is more preferable that it is 3-40 mass parts, It is further more preferable that it is 5-30 mass parts.

  The photosensitive resin composition may contain a thermal polymerization initiator, if necessary, within a range that does not impair the effects exhibited by the above configuration.

  As the thermal polymerization initiator, known ones can be used, for example, benzoyl peroxide, ketone peroxides such as methyl ethyl ketone peroxide, alkyl peroxides such as tertiary butyl peroxide, and peroxydicarbonates. Peroxyketals, peroxyesters, alkyl peresters, and the like can be used. These can be used individually by 1 type or in combination of 2 or more types.

  When the photosensitive resin composition contains a thermal polymerization initiator, the content is from the viewpoint of improving various properties such as insulation, heat resistance, plating resistance, and crack resistance of the cured film. It is preferably 0.1 to 10 parts by mass, more preferably 0.3 to 8 parts by mass, and 0.5 to 5 parts by mass with respect to 100 parts by mass of the total solid content therein. Further preferred.

  Moreover, you may add a filler to the photosensitive resin composition in order to improve various characteristics, such as insulation of a cured film, heat resistance, plating resistance, and crack resistance.

  Examples of the filler include silica, fused silica, talc, alumina, hydrated alumina, barium sulfate, aluminum hydroxide, magnesium hydroxide, calcium hydroxide, aerosil, calcium carbonate, and other inorganic fine particles, powdered epoxy resin, and powdery Examples thereof include organic fine particles such as polyimide particles, and powdered Teflon (registered trademark) particles. These fillers may be subjected to a coupling treatment in advance. These can be used individually by 1 type or in combination of 2 or more types.

  Examples of the method for dispersing the filler in the photosensitive resin composition include known kneading methods such as a kneader, ball mill, bead mill, and three rolls.

  In the case where the photosensitive resin composition contains a filler, the content thereof is the total in the photosensitive resin composition from the viewpoint of improving various properties such as insulation, heat resistance, plating resistance, crack resistance, etc. of the cured film. It is preferable that it is 2-20 mass parts with respect to 100 mass parts of solid content, It is more preferable that it is 3-18 mass parts, It is further more preferable that it is 5-15 mass parts.

  In addition, the photosensitive resin composition may be a dye such as malachite green, a photochromic agent such as leuco crystal violet, a plasticizer such as a thermochromic inhibitor or p-toluenesulfonamide, or a phthalocyanine series such as phthalocyanine blue as necessary. , Organic pigments such as azo or inorganic pigments such as titanium dioxide, dispersants, antifoaming agents, stabilizers, adhesion-imparting agents, flame retardants, leveling agents, antioxidants, perfumes or imaging agents Good. These components are preferably contained in an amount of about 0.01 to 20 parts by mass with respect to 100 parts by mass of the solid content of the photosensitive resin composition. Moreover, said component can be used individually by 1 type or in combination of 2 or more types.

  In addition, the photosensitive resin composition may be methanol, ethanol, acetone, methyl ethyl ketone, cyclohexanone, methyl cellosolve, ethyl cellosolve, xylene, toluene, N, N-dimethylformamide, N, N-dimethylacetamide, propylene glycol as necessary. A solid composition may be dissolved in a solvent such as monomethyl ether, ethylene glycol monoethyl ether, ethyl ethoxypropionate, or a mixed solvent thereof to form a liquid composition. Here, the liquid composition is preferably a solution having a nonvolatile content of 30 to 70% by mass.

  In addition, the photosensitive resin composition has a glass transition temperature of 90 ° C. after curing in an exposure step and / or a post-heating step described later from the viewpoint of improving various properties such as heat resistance and high temperature and high humidity resistance of the cured film. It is preferable that it is above, it is more preferable that it is 100-180 degreeC, and it is still more preferable that it is 100-150 degreeC.

  In addition, the photosensitive resin composition may be used after being applied as a liquid resist on a metal surface such as copper, a copper-based alloy, iron, or an iron-based alloy and then dried and then coated with a protective film as necessary. It may be used in the form of a photosensitive film described later.

  Next, the photosensitive film using the photosensitive resin composition concerning this embodiment is demonstrated.

  FIG. 1 is a schematic cross-sectional view showing a preferred embodiment of the photosensitive film. The photosensitive film 1 shown in FIG. 1 includes a support 10, a photosensitive resin composition layer 20 provided on the support 10, and the opposite side of the support 10 on the photosensitive resin composition layer 20. And a protective film 30 covering the surface. The photosensitive resin composition layer 20 is a layer made of the photosensitive resin composition.

  The photosensitive resin composition layer 20 is formed by dissolving the photosensitive resin composition in the solvent or mixed solvent to obtain a solution having a solid content of 30 to 70% by mass, and then applying the solution onto the support 10. It is preferable to do.

  Although the thickness of the photosensitive resin composition layer 20 varies depending on the application, the thickness after removing the solvent by heating and / or hot air blowing from the viewpoint of improving the ease of production, sensitivity, and resolution in a balanced manner. However, it is preferable that it is 1-100 micrometers, and it is more preferable that it is 10-50 micrometers.

  Examples of the support 10 include polymer films having heat resistance and solvent resistance such as polyethylene terephthalate, polypropylene, polyethylene, and polyester.

  The thickness of the support 10 is preferably 5 to 100 μm, and more preferably 10 to 30 μm. When the thickness is 5 μm or more, the support tends to be hardly broken when the support is peeled off before development, and when the thickness is 100 μm or less, the resolution and flexibility tend to be better. .

  The photosensitive film 1 consisting of two layers of the support 10 and the photosensitive resin composition layer 20 as described above or the photosensitive film consisting of three layers of the support 10, the photosensitive resin composition layer 20 and the protective film 30. For example, 2 may be stored as it is, and can be stored in a roll shape around a winding core with the protective film 30 interposed.

  The resist pattern forming method using the photosensitive resin composition according to the present embodiment can be applied by directly applying a solution of the photosensitive resin composition on the substrate, or from the above-described photosensitive film as necessary. And laminating the photosensitive film on the substrate in the order of the photosensitive layer and the support, and if necessary, irradiating a predetermined portion of the photosensitive layer with actinic rays through the support to illuminate the exposed portion. An exposure step for curing, and a development step for removing a portion other than the exposed portion of the photosensitive layer from the substrate. Moreover, it is preferable to include the post-heating process which further thermosets the exposed part of the said photosensitive layer as needed. Here, as the substrate, an insulating layer and a conductor layer (copper, copper-based alloy, nickel-based alloy such as nickel, chromium, iron, stainless steel, preferably copper, copper-based alloy, A substrate provided with an iron-based alloy) can be suitably used.

  As a lamination method in the above-mentioned lamination process, there are a method of applying a solution of a photosensitive resin composition by a known method, a method of laminating by pressing a photosensitive resin composition layer of a photosensitive film to a substrate while heating, and the like. Can be mentioned. The surface to be laminated is usually the surface of the conductor layer of the substrate, but may be a surface other than the conductor layer.

  From the standpoint of adhesion and followability, the heating temperature of the photosensitive layer when laminating the photosensitive film is preferably 50 to 130 ° C., and the pressing pressure is preferably about 0.1 to 1.0 MPa. The ambient atmospheric pressure is more preferably 4000 Pa or less, but these conditions are not particularly limited. If the photosensitive layer is heated to 50 to 130 ° C. as described above, it is not necessary to pre-heat the substrate in advance, but the substrate can be pre-heated in order to further improve the stackability.

  After the lamination is completed in this manner, in the exposure step, a predetermined portion of the photosensitive layer is irradiated with actinic rays to photocur the exposed portion. Examples of the method for forming the photocured portion include a method of irradiating an actinic ray in an image form through a negative or positive mask pattern called an artwork. Further, exposure by a direct drawing method having no mask pattern such as an LDI method or a DLP (Digital Light Processing) exposure method is also possible. At this time, when the support present on the photosensitive resin composition layer is transparent, it can be irradiated with actinic rays as it is, but when opaque, the photosensitive resin composition is removed after removing the support. Irradiate the layer with actinic rays.

  As the active light source, a known light source, for example, a carbon arc lamp, a mercury vapor arc lamp, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, a YAG laser, a semiconductor laser, or the like that emits ultraviolet rays effectively is used. it can. Moreover, what can radiate | emit visible light effectively, such as a flood bulb for photography, a solar lamp, can also be used.

  Next, after exposure, when a support is present on the photosensitive resin composition layer, after removing the support, in the development process, a photosensitive resin other than the photocured portion by wet development, dry development, or the like. The composition layer is removed and developed to form a resist pattern.

  In the case of wet development, development is performed using a developer such as an alkaline aqueous solution by a known method such as spraying, rocking immersion, brushing, or scraping. As the developer, a developer that is safe and stable and has good operability is used. For example, a dilute solution (1 to 5% by mass aqueous solution) of sodium carbonate at 20 to 50 ° C. is used.

  When the resist pattern obtained by the above-described forming method is used as, for example, a solder resist or an interlayer insulating film of a printed wiring board, various properties such as heat resistance, chemical resistance, and high temperature and high humidity resistance are obtained after the completion of the development process. For the purpose of improving, it is preferable to perform ultraviolet irradiation with a high-pressure mercury lamp or heating with an oven.

In the case of irradiating ultraviolet rays, the irradiation amount can be adjusted as necessary. For example, the irradiation can be performed at an irradiation amount of about 0.2 to 10 J / cm ² . Moreover, when heating, it is preferable to carry out for about 15 to 90 minutes in the range of about 100-170 degreeC. Furthermore, both ultraviolet irradiation and heating may be performed, and after one of them is performed, the other can be performed.

  Moreover, when using the resist pattern obtained by the above-mentioned formation method as an interlayer insulation film, it is preferable to perform a surface roughening (desmear) process for the purpose of improving the adhesion of the plated copper in the plating process described later.

  Surface roughening is performed mechanically or chemically to form a fine uneven shape on the surface. By forming this fine uneven shape, the adhesion of the plated copper formed on the interlayer insulating film can be improved. Surface roughening can be performed by using mechanical polishing such as buff polishing, belt sander polishing, sand blasting, and liquid honing, chemical roughening with chromic acid or permanganic acid, and the like in combination.

  After roughening, the surface is supported with a plating catalyst that serves as a precipitation nucleus for electroless plating. As the plating catalyst, for example, various known treatment liquids in which a metal colloid such as palladium is dispersed in various dispersion media can be used, and the substrate that has been pretreated for cleaning is immersed in the treatment liquid. Thus, the loading of the plating catalyst is achieved. After the plating catalyst is supported, electroless plating is performed, but normal electroless plating conditions are applied as they are.

  The substrate after electroless plating is heat-treated (baked) as necessary. By baking, the adhesion between the electroless plating and the interlayer insulating film is increased, and the peel strength of the plating can be increased.

  As a method for forming a circuit, a normal circuit forming process such as a panel plating method or a semi-additive method is applied as it is.

  When the pattern is formed by electroplating, heat treatment (after cure) is performed as necessary. Thereby, the adhesiveness of electroplating and an interlayer insulation film increases, and the peeling strength of plating can be raised.

  The resist pattern obtained by the above-described forming method is preferably used as a solder resist formed on a printed wiring board or as an interlayer insulating film of a multilayer wiring board. The cured film formed from the photosensitive resin composition of the present invention has excellent insulating properties, heat resistance, plating resistance, crack resistance, HAST resistance, and desmear resistance. It is effective as

  EXAMPLES Hereinafter, although an Example demonstrates this invention still in detail, this invention is not limited to these Examples.

(Examples 1-4 and Comparative Examples 1-2)

(Synthesis of epoxy resin-encapsulated microcapsules (D3))
First, 100 parts by weight of a formalin solution (37 wt%), 0.5 parts by weight of triethanolamine, and 65 parts by weight of urea were reacted by stirring at a temperature of 70 ° C. for about 2 hours, diluted with 800 parts by weight of cold water, and urea- A solution of formaldehyde polymer was prepared. The pH of this solution was adjusted to about 7 and the temperature was adjusted to 25 ° C. respectively, and liquid bisphenol A type epoxy resin having an epoxy equivalent of 184 to 194 (trade name Epicoat 828, manufactured by Japan Epoxy Resin Co., Ltd.) was added at about 1200 rpm. The mixture was stirred to make the solution uniform, and the solution was adjusted to pH 2.2 with 3N hydrochloric acid and reacted at a temperature of about 40 ° C. for 12 hours. After completion of the reaction, the pH was returned to neutral, and the obtained microcapsule (D3) was washed with water and filtered to obtain an epoxy resin-encapsulated microcapsule. This microcapsule (D3) had an average particle size of 50 μm, an encapsulation rate of about 70% by mass, an average wall thickness of 1.1 μm, and an average breaking strength of 11.6 MPa.

  As an epoxy resin-encapsulated microcapsule (D1), N-580 (aqueous dispersion, nonvolatile content 40% by mass, average particle size 0.45 μm, encapsulation rate about 70% by mass, manufactured by Chukyo Yushi Co., Ltd.) As the epoxy resin-encapsulated microcapsule (D2), N-605 (aqueous dispersion, nonvolatile content 40% by mass, average particle size 0.35 μm, encapsulation rate approximately 70% by mass, manufactured by Chukyo Yushi Co., Ltd.) was used.

(Preparation of photosensitive resin composition)
The raw materials were blended as shown in Table 1, and solutions of the photosensitive resin compositions of Examples 1 to 4 and Comparative Examples 1 to 2 were produced.

  In Examples 1 to 4 and Comparative Examples 1 and 2, as the component (A), tetrahydroxyphthalic anhydride-modified bisphenol F type epoxy acrylate (manufactured by Nippon Kayaku Co., Ltd., trade name ZFR-1158) (below) , “(A1)”), and a copolymer of methacrylic acid / methyl methacrylate / ethyl acrylate (12/58/30 (weight ratio), weight average molecular weight 70000, acid value 78 mgKOH / g) ( Hereinafter, “(a2)”) was used.

  As the component (B), 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane (manufactured by Hitachi Chemical Co., Ltd., product name “FA-321M”) (hereinafter, “(B1)” And dipentaerythritol hexaacrylate (manufactured by Nippon Kayaku Co., Ltd., product name “DPHA”) (hereinafter referred to as “(B2)”).

  Further, as component (C), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1 (Ciba Specialty Chemicals, product name “IRGACURE369”) was used. .

  Further, as the component (E), blocked isocyanate BL-3175 (manufactured by Sumika Bayer Urethane Co., Ltd.) (hereinafter referred to as “(E1)”) was used.

  Moreover, in the comparative example 2, the liquid epoxy oligomer (Epicoat 828, Japan Epoxy Resin Co., Ltd. product) was used as an alternative component of (D) component.

  Next, these photosensitive resin composition solutions are uniformly coated on a 16 μm-thick polyethylene terephthalate film (trade name “HTF01” manufactured by Teijin Ltd.) and dried for 10 minutes in a hot air convection dryer at 95 ° C. As a result, a photosensitive layer was formed on the support. The film thickness after drying of the photosensitive layer was 30 μm.

  Subsequently, a 25 μm thick polyethylene film (trade name “T-5N”, manufactured by Tamapoly Co., Ltd.) is pasted as a protective film on the surface of the photosensitive resin composition layer opposite to the side in contact with the support layer. Together, a photosensitive film was obtained.

(Evaluation substrate manufacturing method and evaluation method)
The copper surface of a glass cloth base epoxy resin double-sided copper clad laminate (copper foil thickness 18 μm, having copper foil layers on both sides, manufactured by Hitachi Chemical Co., Ltd., trade name “MCL-E-679FG”) Polishing using a polishing machine (manufactured by Sankei Co., Ltd.) having a brush equivalent to 600, washing with water, drying with an air flow, and peeling the polyethylene film on the copper surface of the obtained copper-clad laminate The photosensitive film was subjected to thermocompression bonding using a press-type vacuum laminator (trade name MVLP-500, manufactured by Meiki Seisakusho Co., Ltd.) at an upper plate temperature of 50 ° C., a lower plate temperature of 50 ° C., a degree of vacuum of 5 hPa or less, and a press time of 30 seconds. . This produced the evaluation board | substrate with which the photosensitive layer and the support body were laminated | stacked in this order on the board | substrate.

  The evaluation substrate after lamination was allowed to stand at room temperature (25 ° C.) for 1 hour, and then exposed through a support at a predetermined exposure amount using an exposure machine (manufactured by Oak Co., Ltd.) EXM-1201 having a high-pressure mercury lamp. Exposed.

  The exposed evaluation substrate was allowed to stand at room temperature for 10 minutes, and then the polyethylene terephthalate film was removed, followed by spray development with a 1% by mass aqueous sodium carbonate solution at 30 ° C. for 60 seconds to remove the unexposed photosensitive layer.

After spray development, UV irradiation of 1 J / cm ² was performed using an ultraviolet irradiation device manufactured by Oak Manufacturing Co., Ltd., and further heat treatment was performed at 160 ° C. for 60 minutes to obtain a wiring board on which a resist pattern was formed.

[sensitivity]
The sensitivity was evaluated as the amount of exposure energy (mJ / cm ² ) necessary for obtaining 8/21 steps with a 21-step tablet manufactured by Eastman Kodak Co., Ltd.

[Resolution]
In addition, the resist pattern obtained with an exposure energy amount of 8/21 steps of the step tablet is observed with an optical microscope, and the resolution is determined from the via diameter (diameter) (μm) of the opening pattern in which the unexposed part can be completely removed. (Μm) was evaluated.

[Elastic modulus / elongation / breaking strength]
The cured product of the photosensitive layer was cut into a length of 70 mm and a width of 10 mm, and using an autograph AGS-100NH manufactured by Shimadzu Corporation, the distance between chucks was 50 mm, the pulling speed was 20 mm / min, and the room temperature (25 ° C.). The initial elastic modulus, elongation and breaking strength were measured (n = 5).

[1 mass% weight loss temperature]
The photosensitive layer of the photosensitive film is exposed under the same conditions as in the above-described evaluation of resolution, and about 2.5 mg of the obtained cured film is taken on an aluminum sample pan, and TG-DTA 6300 (manufactured by Seiko Instruments Inc.). ) Was used to measure the temperature when the weight of the cured film was reduced by 1 mass% under a measurement temperature of 50 to 350 ° C., a heating rate of 10 ° C./min, and an air atmosphere. The lower the 1% by weight weight loss temperature, the better.

[Water absorption rate]
The water absorption of the cured film was measured according to JIS K7209 “Testing method for water absorption of plastic and boiling water absorption”. Specifically, the photosensitive resin composition solution was applied onto a silicon wafer and dried, and a photosensitive layer was formed so that the film thickness after drying was 25 ± 10 μm. The obtained photosensitive layer was exposed with an energy amount of 1 J using a parallel light exposure machine (EXM-1201 (manufactured by Oak Manufacturing)), and further heated at 160 ° C. for 60 minutes to obtain a cured film. The weight of the silicon wafer on which the cured film was formed was measured, immersed in pure water for 24 hours at room temperature (25 ° C.), then the weight was measured, and the water absorption rate of the cured film was measured. The measurement was performed three times, and the average of the three times was taken as the water absorption rate. The smaller the value of water absorption, the better.

[Storage stability of film]
The photosensitive film was stored in a dark place at 50 ° C., and the development time was examined over time. The development time that is less than 30% compared to the development time immediately after film production is usable, the one that is longer than 30% is unusable, and the shortest elapsed time (h) when the film becomes unusable Was used to evaluate the storage stability of the film. The storage stability is better as the elapsed time (h) is longer.

The wiring board on which the resist pattern obtained by the above-described method was formed was subjected to surface roughening (desmear), electroless copper plating, and electrolytic copper plating under the conditions shown in Table 2 to obtain a multilayer wiring board.

[Desmear resistance]
After roughening the substrate under the roughening conditions shown in Table 2, the cured film was visually observed for swelling and peeling to evaluate desmear resistance.
○: No floating, blistering and peeling ×: Floating, swelling and peeling occurred

[Plating resistance]
After the electroless copper plating was applied on the resist pattern under the plating conditions shown in Table 2, the cured film was visually observed for bulging and peeling to evaluate the plating resistance.
○: No floating, blistering and peeling ×: Floating, swelling and peeling occurred

  As is apparent from Table 3, Examples 1 to 4 including the component (A), the component (B), the component (C) and the component (D) show good sensitivity and resolution, and are in a film state. Excellent storage stability and excellent properties such as desmear resistance and plating resistance. In Examples 1 to 3, in which the average particle size of the component (D) is in the range of 10 nm to 10 μm, the resolution is further improved.

It is a figure which shows typically the cross-sectional structure of the photosensitive film of suitable embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Photosensitive film, 10 ... Support body, 20 ... Photosensitive resin composition layer, 30 ... Protective film

Claims (14)

  (A) Photosensitivity containing a polymer having a carboxyl group, (B) a photopolymerizable compound having an ethylenically unsaturated bond, (C) a photopolymerization initiator, and (D) an epoxy resin-encapsulated microcapsule. Resin composition.   The photosensitive resin composition of Claim 1 whose average particle diameter of the said (D) epoxy resin inclusion microcapsule is 10 nm-10 micrometers.   The (D) epoxy resin-encapsulated microcapsule has a core material made of epoxy resin and a hollow spherical wall material enclosing the core material, and the wall material is destroyed by heating at 120 to 180 ° C. The photosensitive resin composition of Claim 1 or 2 which is.   The photosensitive resin composition of Claim 3 which the said wall material consists of 1 type, or 2 or more types of resin selected from a polyurethane, a polyurea, a polystyrene, and a urea resin.   The photosensitive resin composition as described in any one of Claims 1-4 whose acid value of the polymer which has the said (A) carboxyl group is 30-110 mgKOH / g.   The photosensitive resin composition as described in any one of Claims 1-5 in which the polymer which has the said (A) carboxyl group contains the polymerizable compound which has (a1) carboxyl group and an ethylenically unsaturated bond.   A photosensitive film comprising: a support; and a photosensitive layer made of the photosensitive resin composition according to any one of claims 1 to 6 formed on the support. A laminating step of laminating a photosensitive layer made of the photosensitive resin composition according to any one of claims 1 to 6 on a substrate;
An exposure step of irradiating a predetermined portion of the photosensitive layer with an actinic ray to photocure an exposed portion; and
A developing step for removing a portion other than the exposed portion of the photosensitive layer;
A method for forming a resist pattern. A laminating step of laminating a photosensitive layer made of the photosensitive resin composition according to any one of claims 1 to 6 on a substrate;
An exposure step of irradiating a predetermined portion of the photosensitive layer with an actinic ray to photocure an exposed portion; and
A developing step for removing a portion other than the exposed portion of the photosensitive layer;
A post-heating step of further thermosetting the exposed portion of the photosensitive layer;
A method for forming a resist pattern.   The soldering resist which consists of a hardened | cured material of the photosensitive resin composition as described in any one of Claims 1-6 formed on the board | substrate.   The interlayer insulation film which consists of hardened | cured material of the photosensitive resin composition as described in any one of Claims 1-6 formed on the board | substrate.   A method for manufacturing a printed wiring board, comprising plating a substrate on which a resist pattern is formed by the method for forming a resist pattern according to claim 8.   A method for manufacturing a printed wiring board, wherein a substrate on which a resist pattern is formed by the method for forming a resist pattern according to claim 8 or 9 is roughened and the roughened substrate and / or the resist pattern is plated.   A printed wiring board provided with a board | substrate and the hardened | cured material of the photosensitive resin composition as described in any one of Claims 1-6 formed on this board | substrate.

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