JP5218828B2 - Photosensitive resin composition, photosensitive film using the same, resist pattern forming method and permanent resist - Google Patents

Description

  The present invention relates to a photosensitive resin composition, a photosensitive film using the same, a method for forming a resist pattern, and a permanent resist.

  With the miniaturization, weight reduction, and multifunctionality of various electrical and electronic devices, the semiconductor elements, semiconductor packages, printed wiring boards, flexible wiring boards, etc. that form them have become highly precise and can form fine opening patterns. A photosensitive solder resist is required.

  In general, the solder resist is suitable for a temperature cycle test (TCT) of −55 ° C. to 125 ° C. in addition to characteristics such as developability, high resolution, insulation, surface hardenability, solder heat resistance and plating resistance. Characteristics such as crack resistance and HAST resistance between fine wirings for a super accelerated high temperature and high humidity life test (HAST) are required.

  In a soldering process for bonding solder in a soldering process such as IR reflow, a fine opening pattern in which a part of the conductor layer is exposed is provided. The resist shape of the opening is required to be a forward taper shape as shown in FIG. 1A or a straight shape as shown in FIG. 1B from the viewpoint of solder adhesion. This is because if the resist shape is a reverse taper shape such as an undercut or an overhang as shown in FIGS. 1C and 1D, it is difficult for the solder to attach, and it becomes easier to remove the solder in the subsequent steps. Because. In particular, for solder resists for use in package substrates in recent years, in order to cope with the increase in flip chip connection of the package structure and the narrowing of the bump pitch, it has a fine opening pattern and the resist shape is It is required to be excellent.

  At present, the photosensitive resin composition used for forming the solder resist is a liquid 2 in which an epoxy resin as a curing agent and a carboxylic acid-containing photosensitive prepolymer for imparting alkali developability are separately separated. Liquid type is mainstream. As the photosensitive prepolymer, an alkali developable photosensitive prepolymer obtained by adding acrylic acid to an epoxy resin such as a novolak type, bisphenol A type, or bisphenol F type, and then acid-modified is widely used (for example, (See Patent Document 1).

  On the other hand, in recent years, an LDI (Laser Direct Imaging) method has attracted attention as a method for directly drawing a circuit manufactured by CAD (Computer-Aided Design) without using a mask, using a laser beam. Since the LDI method does not use a photomask, the mask cost can be reduced, the alignment accuracy of the resist opening and the scaling correction are easy, and in addition, the adhesion of foreign matters to the mask, dirt, and scratches can be managed. It has many advantages such as unnecessary. However, since the LDI method performs exposure while moving the laser beam at a high speed, there is a problem that the amount of exposure energy is small compared to a general batch exposure method and the cost is greatly increased in terms of throughput. Therefore, in the LDI method, there is a demand for a photosensitive resin composition with higher sensitivity that can be sufficiently photocured even with a small exposure energy amount.

Japanese Patent Laid-Open No. 11-240930

  However, the conventional photosensitive resin composition does not have sufficient sensitivity that can correspond to the LDI system, and is difficult to apply to the LDI system. In addition, the sensitivity can be improved by adding a large amount of photopolymerization initiator or sensitizer to the conventional photosensitive resin composition, but in that case, the resist shape tends to deteriorate, and the resist This causes a problem that the outgas generated during heat curing or solder reflow increases with the amount of photopolymerization initiator.

  Moreover, in the above-mentioned conventional liquid two-component type solder resist, the epoxy resin as a curing agent and the photosensitive prepolymer having a carboxylic acid necessary for imparting developability react at room temperature (25 ° C.), so that storage stability is improved. Insufficient, especially when a dry film was formed as a photosensitive film, it was difficult to handle.

  The present invention has been made in view of the above problems, and even when applied to the LDI method, excellent sensitivity is obtained, and sufficient storage stability is obtained, and there is no undercut or overhang. The present invention provides a photosensitive resin composition, a photosensitive film, a resist pattern forming method and a permanent resist capable of forming a resist pattern having a resist shape.

The present invention includes (a) a photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group, (b) a photopolymerizable monomer having an ethylenically unsaturated group, (c) a photopolymerization initiator, and (d) heat. A photosensitive resin composition containing a curing agent, wherein (a) the photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group has two or more hydroxyl groups and an ethylenically unsaturated group in the molecule. A maleimide compound containing a polyurethane compound obtained by reacting an epoxy acrylate compound, a diisocyanate compound, and a diol compound having a carboxyl group, wherein the (d) thermosetting agent is represented by the following general formula (1) The photosensitive resin composition containing this is provided.

(In the general formula (1), R ¹ represents any group selected from an oxygen atom, an alkylene group, and an arylene group or a divalent organic group containing two or more groups, and R ² and R ³ are each independently selected. Represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom, and m and n each independently represent an integer of 1 to 4. When m and n are 2 or more, A plurality of R ² and R ³ may be the same or different.)

  According to the photosensitive resin composition of the present invention, when the phenylene group bonded to the maleimide group in the general formula (1) contains a maleimide compound having one or more substituents, the photosensitive resin composition is applied to the LDI system. However, excellent sensitivity can be obtained, a good resist shape without undercut or overhang can be formed, and a photosensitive film having sufficient storage stability can be formed.

  Moreover, it is preferable that the photosensitive resin composition of this invention further contains an acrylic copolymer as (e) binder polymer. Thereby, the photosensitive resin composition of this invention becomes a thing with more excellent coating film property and alkali developability.

The photosensitive resin composition of the present invention is an epoxy acrylate in which (a) the photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group has two or more hydroxyl groups and an ethylenically unsaturated group in the molecule. Although the polyurethane compound obtained by making a compound, a diisocyanate compound, and the diol compound which has a carboxyl group react is contained , by this, the photosensitive resin composition of this invention becomes a thing with more excellent sensitivity.

  In the photosensitive resin composition of the present invention, the (c) photopolymerization initiator preferably contains an acridine derivative. Thereby, the sensitivity and the resist shape of the photosensitive resin composition of the present invention are more excellent.

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

  According to the photosensitive film of the present invention, by including the photosensitive resin composition layer comprising the photosensitive resin composition of the present invention, excellent sensitivity can be obtained even when applied to the LDI system, and sufficient storage is achieved. It is possible to form a resist pattern having a good resist shape that is stable and has no undercut or overhang.

The present invention also provides a photosensitive resin composition layer comprising the above-mentioned photosensitive resin composition on a circuit-forming substrate, and irradiates the photosensitive resin composition layer with an actinic ray in an image form to photocure the exposed portion. A method for forming a resist pattern is provided in which unexposed portions are removed by development.
Further, the present invention provides a photosensitive resin composition layer comprising the above photosensitive resin composition on a circuit forming substrate, and irradiates the photosensitive resin composition layer with an actinic ray in an image form by a direct drawing method. A method for forming a resist pattern is provided, in which a portion is photocured and an unexposed portion is removed by development.

  The present invention also provides a permanent resist formed by the method for forming a resist pattern.

  According to the present invention, even when applied to the LDI method, excellent sensitivity is obtained, and a resist pattern having a satisfactory resist shape having sufficient storage stability and having no undercut or overhang is formed. The photosensitive resin composition, the photosensitive film, and the photosensitive permanent resist which can be provided can be provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail.

  First, the photosensitive resin composition which concerns on suitable embodiment is demonstrated. In the present invention, (meth) acrylic acid means acrylic acid and methacrylic acid corresponding thereto, (meth) acrylate means acrylate and corresponding methacrylate, (meth) acryloyl group means acryloyl group and The methacryloyl group corresponding to it means a (meth) acryloxy group means an acryloxy group and a methacryloxy group corresponding to it.

  As the photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group as the component (a) of the present invention, for example, an esterified product of an epoxy compound (a1) and an unsaturated monocarboxylic acid (a2) is saturated or unsaturated. An addition reaction product to which a polybasic acid anhydride (a3) has been added can be used. These can be obtained by the following two-step reaction. In the first reaction (hereinafter referred to as “first reaction” for convenience), the epoxy compound (a1) and the unsaturated monocarboxylic acid (a2) react. In the next reaction (hereinafter referred to as “second reaction” for convenience), the esterified product produced in the first reaction reacts with the saturated or unsaturated polybasic acid anhydride (a3).

  Although there is no restriction | limiting in particular as said epoxy compound (a1), For example, a bisphenol type epoxy compound, a novolak type epoxy compound, a biphenyl type epoxy compound, a polyfunctional epoxy compound, etc. are mentioned.

  As the bisphenol type epoxy compound, those obtained by reacting bisphenol A type, bisphenol F type and epichlorohydrin are suitable. GY-260, GY-255, XB-2615 manufactured by Ciba-Geigy Corporation, Epicoat manufactured by Japan Epoxy Resin Co., Ltd. Epoxy compounds such as 828, 1007, and bisphenol A type, bisphenol F type, hydrogenated bisphenol A type, amino group-containing, alicyclic, or polybutadiene-modified are preferably used.

  Suitable novolak-type epoxy compounds are those obtained by reacting phenol, cresol, halogenated phenol, alkylphenols and formaldehyde with novolaks and epichlorohydrin, produced by Toto Kasei Co., Ltd. YDCN-701,704, YDPN-638,602, DEN-431,439 manufactured by Dow Chemical Company, 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, BREN etc. are mentioned.

  Examples of other epoxy compounds include salicylaldehyde-phenol or cresol type epoxy compounds (EPPN502H, FAE2500, etc., manufactured by Nippon Kayaku Co., Ltd.), Epicron 840, 860, 3050, manufactured by Dainippon Ink & Chemicals, Inc. DER-330,337,361 manufactured by Dow Chemical Company, Celoxide 2021, manufactured by Daicel Chemical Industries, Ltd., TETRAD-X, C manufactured by Mitsubishi Gas Chemical Company, Inc., EPB-13,27 manufactured by Nippon Soda Co., Ltd., etc. may be used. it can. These may be used alone or in combination of two or more, and a mixture or a block copolymer may be used.

  Examples of the unsaturated monocarboxylic acid (a2) include (meth) acrylic acid, crotonic acid, cinnamic acid, and saturated or unsaturated polybasic acid anhydrides and (meth) acrylates having one hydroxyl group in one molecule. Or the reaction material of the half-ester compound of a saturated or unsaturated dibasic acid and an unsaturated monoglycidyl compound is mentioned. Examples of the reactant include phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, succinic acid, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and tris (hydroxyethyl) isocyanurate. Examples thereof include reactants obtained by reacting di (meth) acrylate, glycidyl (meth) acrylate and the like in an equimolar ratio by a conventional method. These unsaturated monocarboxylic acids can be used alone or in combination. Among these, acrylic acid is preferable.

  Examples of the saturated or unsaturated polybasic acid anhydride (a3) include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride Methylhexahydrophthalic anhydride, ethylhexahydrophthalic anhydride, itaconic anhydride, trimellitic anhydride, and the like.

  In the first reaction, a hydroxyl group is generated by an addition reaction between the epoxy group of the epoxy compound (a1) and the carboxyl group of the unsaturated monocarboxylic acid (a2). In the first reaction, the ratio of the epoxy compound (a1) to the unsaturated monocarboxylic acid (a2) is such that the unsaturated monocarboxylic acid (a2) is 0.001 equivalent to 1 equivalent of the epoxy group of the epoxy compound (a1). The ratio is preferably 7 to 1.05 equivalent, and more preferably 0.8 to 1.0 equivalent.

  The epoxy compound (a1) and the unsaturated monocarboxylic acid (a2) can be reacted by dissolving in an organic solvent. Examples of the organic solvent include ketones such as ethyl methyl ketone and cyclohexanone, aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene, methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, Glycol ethers such as dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether and triethylene glycol monoethyl ether, esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate and carbitol acetate, aliphatic carbonization such as octane and decane Petroleum solvents such as hydrogen, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha can be used.

  In the first reaction, it is preferable to use a catalyst in order to accelerate the reaction. Examples of the catalyst that can be used include triethylamine, benzylmethylamine, methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylammonium iodide, and triphenylphosphine. It is preferable that the usage-amount of a catalyst shall be 0.1-10 mass parts with respect to a total of 100 mass parts of an epoxy compound (a1) and unsaturated monocarboxylic acid (a2).

  In the first reaction, in order to prevent polymerization between the epoxy compounds (a1) or between the unsaturated monocarboxylic acids (a2) or between the epoxy compound (a1) and the unsaturated monocarboxylic acid (a2), a polymerization inhibitor is used. It is preferable to use it. As the polymerization inhibitor, for example, hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol, pyrogallol and the like can be used. It is preferable that the usage-amount of a polymerization inhibitor shall be 0.01-1 mass part with respect to a total of 100 mass parts of an epoxy compound (a1) and unsaturated monocarboxylic acid (a2). 60-150 degreeC is preferable and, as for the reaction temperature of a 1st reaction, 80-120 degreeC is more preferable.

  In the first reaction, an unsaturated monocarboxylic acid (a2) and a polybasic acid anhydride such as trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, biphenyltetracarboxylic anhydride, etc., if necessary Can be used in combination.

  In the second reaction, when the hydroxyl group formed in the first reaction and the hydroxyl group originally present in the epoxy compound (a1) undergo a half-ester reaction with the acid anhydride group of the saturated or unsaturated polybasic acid anhydride (a3). Inferred. Here, 0.1 to 1.0 equivalent of polybasic acid anhydride (a3) can be reacted with 1 equivalent of hydroxyl group in the resin obtained by the first reaction. By adjusting the amount of the polybasic acid anhydride (a3) within this range, the acid value of the component (a) can be adjusted.

  Examples of the photosensitive prepolymer include CCR-1218H, CCR-1159H, CCR-1222H, PCR-1050, TCR-1335H, ZAR-1035, ZAR-2001H, ZFR-1185, and ZCR-1569H (Nippon Kayaku) (Trade name, manufactured by Co., Ltd.) are commercially available.

  The photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group as the component (a) of the present invention includes an epoxy acrylate compound having two or more hydroxyl groups and an ethylenically unsaturated group in the molecule, a diisocyanate compound, It is preferable to contain a polyurethane compound obtained by reacting a diol compound having a carboxyl group.

  As described above, the polyurethane compound includes an epoxy acrylate compound having two or more hydroxyl groups and an ethylenically unsaturated group in the molecule (hereinafter referred to as “raw material epoxy acrylate”), a diisocyanate compound (hereinafter referred to as “raw material diisocyanate”). And 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, and compounds obtained by reacting (meth) acrylic acid with epoxy compounds having a fluorene skeleton. Among them, the structure of the hard segment part of the epoxy acrylate compound having two or more hydroxyl groups and ethylenically unsaturated groups in the molecule of the raw material which is one of the main skeletons of polyurethane is preferably a bisphenol A type structure, and UXE-3011 , UXE-3012, UXE-3024 (manufactured by Nippon Kayaku Co., Ltd.) and the like are commercially available. These may be used alone or in combination of two or more.

  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. These may be used alone or in combination of two or more.

  The raw material diol is a compound having two hydroxyl groups such as an alcoholic hydroxyl group and / or a phenolic hydroxyl group in the molecule and 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.

  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 this reaction, a so-called urethanization reaction occurs mainly between the hydroxyl group in the raw material 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, an intermediate in which a structural unit derived from a raw material epoxy acrylate and a structural unit derived from a raw material diol are alternately or block-polymerized via a structural unit derived from a raw material diisocyanate. Arise.

  Next, such an intermediate and raw material epoxy are reacted to obtain a polyurethane compound. In this reaction, a so-called epoxycarboxylation reaction occurs mainly between the carboxyl group derived from the diol compound in the intermediate and the epoxy group of the raw material epoxy. The polyurethane compound thus obtained has, for example, a main chain formed from the above-described intermediate and a side chain containing an ethylenically unsaturated group derived from the raw material epoxy acrylate or the raw material epoxy.

  An example of such a polyurethane compound is a compound represented by the following general formula (2).

ここで、一般式（２）中、Ｒ^１１はエポキシアクリレートの残基、Ｒ^１２はジイソシアネートの残基、Ｒ^１３は炭素数１〜５のアルキル基、Ｒ^１４は水素原子又はメチル基を示す。なお、残基とは、原料成分から結合に供された官能基を除いた部分の構造をいう。また、式中に複数ある基は、それぞれ同一でも異なってもいてもよい。また、上記ポリウレタン化合物が有する末端の水酸基は、飽和若しくは不飽和多塩基酸無水物で処理されていてもよい。

Here, in the general formula (2), R ¹¹ is an epoxy acrylate residue, R ¹² is a diisocyanate residue, R ¹³ is an alkyl group having 1 to 5 carbon atoms, and R ¹⁴ is 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. The terminal hydroxyl group of the polyurethane compound may be treated with a saturated or unsaturated polybasic acid anhydride.

  In the process for producing the polyurethane compound described above, in the step of obtaining the intermediate, in addition to the raw material epoxy acrylate, the raw material diol and the raw material diisocyanate, a diol compound different from these may be further added. 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.

  Moreover, you may make the polyurethane compound mentioned above and raw material epoxy react further. In this reaction, a so-called epoxycarboxylation reaction occurs mainly between the carboxyl group derived from the diol compound in the polyurethane compound and the epoxy group of the raw material epoxy. Thus, the compound obtained is equipped with the principal chain formed from the polyurethane compound mentioned above, and the side chain containing the ethylenically unsaturated group originating in raw material epoxy acrylate or raw material epoxy, for example.

As the polyurethane compound of the present embodiment, among the compounds represented by the general formula (2), the hard segment part of the raw material epoxy acrylate that becomes one of the main skeletons of the polyurethane, that is, R ¹¹ having a bisphenol A type structure is preferable. . Such a polyurethane compound is commercially available as UXE-3011, UXE-3012, UXE-3024 (sample name, manufactured by Nippon Kayaku Co., Ltd.) and the like. These may be used alone or in combination of two or more.

  When the polyurethane compound is used as the photosensitive prepolymer, the acid value is preferably 20 to 130 mgKOH / g, more preferably 30 to 110 mgKOH / g, still more preferably 40 to 90 mgKOH / g, It is especially preferable that it is 50-80 mgKOH / g. Thereby, the developability with the alkaline aqueous solution of the photosensitive resin composition becomes good, and an excellent resolution can be obtained.

  Here, the acid value can be measured by the following method. First, after precisely weighing about 1 g of the measurement resin solution, 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. 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 0.1N KOH aqueous solution, Wp represents the measurement resin solution weight (g), and I represents the measurement resin. The ratio (% by mass) of the nonvolatile content of the solution is shown.

  The weight average molecular weight of the polyurethane compound is preferably 3000 to 30000, more preferably 5000 to 20000, and particularly preferably 7000 to 15000 from the viewpoint of coating properties.

  The polyurethane compound has good compatibility with an acrylic copolymer having a carboxyl group and a weight average molecular weight of 20,000 to 150,000, and when such a polyurethane compound is used as a photosensitive prepolymer, a more uniform photosensitive resin composition. From the viewpoint of obtaining the above, it is preferable to use the acrylic copolymer together as the binder polymer (e) described later.

  The weight average molecular weight (Mw) can be measured by gel permeation chromatography (GPC) (in terms of standard polystyrene).

  Further, (a) as a photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group, a side chain of a vinyl monomer copolymer that can be copolymerized with (meth) acrylic acid alkyl ester and (meth) acrylic acid, and / or A copolymer having an ethylenically unsaturated bond introduced at the terminal is also applicable. 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 And a vinyl polymerizable monomer such as azobisisobutyronitrile, azobisdimethylvaleronitrile, benzoyl peroxide and the like obtained by general solution polymerization in an organic solvent. be able to. These may be used alone or in combination of two or more.

  A copolymer in which an ethylenically unsaturated bond is introduced into the side chain and / or terminal of the above-mentioned (meth) acrylic acid alkyl ester and vinyl monomer copolymer capable of copolymerization with (meth) acrylic acid is represented by (a) a carboxyl group. The acid value when used as a photosensitive prepolymer having an ethylenically unsaturated group is preferably 20 to 180 mgKOH / g, more preferably 30 to 150 mgKOH / g, and 40 to 120 mgKOH / g. It is particularly preferred. Thereby, the developability with the alkaline aqueous solution of the photosensitive resin composition becomes good, and an excellent resolution can be obtained.

  Moreover, it is preferable that the weight average molecular weight of said (a) photosensitive prepolymer which has a carboxyl group and an ethylenically unsaturated group is 3000-30000 from a coating-film viewpoint, and it is 5000-20000. More preferably, it is particularly preferably 7000 to 15000.

  The component (b) of the present invention is a photopolymerizable monomer having one or more ethylenically unsaturated groups in the molecule. Examples of such photopolymerizable monomers include bisphenol A (meth) acrylate compounds, compounds obtained by reacting polyhydric alcohols with α, β-unsaturated carboxylic acids, and glycidyl group-containing compounds with α, β- Examples thereof include a compound obtained by reacting an unsaturated carboxylic 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) according to this embodiment 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. You may use these individually or in combination of 2 or more types.

  The component (b) according to the present embodiment preferably contains 2,2-bis (4-((meth) acryloxypolyethoxy) phenyl) propane from the viewpoint of improving sensitivity and resolution. 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) propane, 2,2-bis (4-((meth) acryloxyundecaethoxy) phenyl) propane, 2, 2-bis (4-((meth) acryloxydodecaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytridecaethoxy) phenyl) propane, 2,2-bis (4- ( (Meth) acryloxytetradecaethoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypentadecaethoxy) phenyl) propane, and 2,2-bis (4-((meth) acryloxy) Hexadecaethoxy) phenyl) propane and the like. 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 (manufactured by Hitachi Chemical Co., Ltd., trade name) or BPE-500 (manufactured by Shin-Nakamura Chemical Co., Ltd.). , And commercially available as trade name), and 2,2-bis (4- (methacryloxypentadecaethoxy) phenyl) propane is commercially available as BPE-1300 (trade name, manufactured by Shin-Nakamura Chemical Co., Ltd.). Are 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) propane, 2,2-bis (4-((meth) acryloxyundecapropoxy) phenyl) Propane, 2,2-bis (4-((meth) acryloxydodecapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytridecapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxytetradecapropoxy) phenyl) propane, 2,2-bis (4-((meth) acryloxypentadecapropoxy) phenyl) propane, and 2,2-bis (4-(( (Meth) acryloxyhexadecapropoxy) phenyl) propane 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.

  In addition, the component (b) according to the present embodiment includes a compound obtained by reacting a polyhydric alcohol with an α, β-unsaturated carboxylic acid from the viewpoint of improving the balance of adhesion, resolution, and electric corrosion resistance. It is preferable. 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 Chlorate, tetramethylolmethane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, EO-modified glyceryl tri (meth) acrylate, PO-modified glyceryl tri (meth) acrylate, EO Examples thereof include PO-modified glyceryl tri (meth) acrylate. These may be used alone or in combination of two or more.

  Of the above compounds, dipentaerythritol hexaacrylate is commercially available as KAYARAD-DPHA (trade name, manufactured by Toa Gosei Chemical Co., Ltd.), and trimethylolpropane triethoxytriacrylate is commercially available as SR-454 (trade name, manufactured by Nippon Kayaku Co., Ltd.). Are available.

“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 (CH ₃ ) —CH _2. It means having a block structure of —O—) or isopropylene oxide unit (—CH ₂ —CH (CH ₃ ) —O—).

  Examples of the compound obtained by reacting the glycidyl group-containing compound with an α, β-unsaturated carboxylic acid include trimethylolpropane triglycidyl ether tri (meth) acrylate and 2,2-bis (4- (meta ) Acryloxy-2-hydroxy-propyloxy) phenyl and the like. These can be used alone or in combination of two or more. Examples of the α, β-unsaturated carboxylic acid for obtaining the above compound include (meth) acrylic acid.

  Examples of urethane monomers 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. Examples include addition reaction products with diisocyanate compounds, tris ((meth) acryloxytetraethylene glycol isocyanate) hexamethylene isocyanurate, EO-modified urethane di (meth) acrylate, and EO or PO-modified urethane di (meth) acrylate. These can be used alone or in combination of two or more.

  Furthermore, as (meth) acrylic acid alkyl ester, for example, (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid butyl ester, (meth) acrylic acid 2-ethylhexyl ester, and 2 -Hydroxyethyl (meth) acrylate etc. are mentioned. These can be used alone or in combination of two or more.

  Examples of the (c) photopolymerization initiator used in the present invention 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-1,4,4′-bis (dimethylamino) benzophenone (Miherer ketone), 4,4′-bis (Diethylamino) benzophenone, aromatic ketones such as 4-methoxy-4′-dimethylaminobenzophenone, quinones such as alkylanthraquinone and phenanthrenequinone, benzoin compounds such as benzoin and alkylbenzoin, benzoin alkyl ether, and benzoin phenyl ether Benzoin ether compounds, ben Benzyl derivatives such as rudimethyl ketal, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl)- 2,4,5-triarylimidazole dimers such as 5-phenylimidazole dimer, 2- (2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, N-phenylglycine, N- Phenylglycine derivatives, acridine derivatives such as 9-phenylacridine, 1,2-octanedione, 1- [4- (phenylthio)-, 2- ( -Benzoyloxime)], coumarin compounds such as 7-diethylamino-4-methylcoumarin, thioxanthone compounds such as 2,4-diethylthioxanthone, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide And the like can be used in combination.

  The (c) photopolymerization initiator of this embodiment preferably contains an acridine derivative from the viewpoint of improving sensitivity and resist shape. Examples of the acridine derivative include 9-phenylacridine, 9-aminoacridine, 9-pentylaminoacridine, 1,2-bis (9-acridinyl) ethane, 1,3-bis (9-acridinyl) propane, 1,4 -Bis (9-acridinyl) butane, 1,5-bis (9-acridinyl) pentane, 1,6-bis (9-acridinyl) hexane, 1,7-bis (9-acridinyl) heptane, 1,8-bis (9-acridinyl) octane, 1,9-bis (9-acridinyl) nonane, 1,10-bis (9-acridinyl) decane, 1,11-bis (9-acridinyl) undecane, 1,12-bis (9 -Acridinyl) dodecane and other bis (9-acridinyl) alkanes, 9-phenylacridine, 9-pyridylacridine, 9-pyrazy Luacridine, 9-monopentylaminoacridine, 1,3-bis (9-acridinyl) -2-oxapropane, 1,3-bis (9-acridinyl) -2-thiapropane, 1,5-bis (9-acridinyl) -3-thiapentane and the like, among which 1,7-bis (9-acridinyl) heptane is more preferable. 1,7-bis (9-acridinyl) heptane is commercially available as N-1717 (manufactured by Adeka Corporation, trade name).

  The (c) photopolymerization initiator of this embodiment preferably contains a thioxanthone compound from the viewpoint of improving sensitivity and resist shape. Examples of the thioxanthone compounds include 2-chlorothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, isopropylthioxanthone, 2,4-dichlorothioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, and the like. Among them, it is more preferable that 2,4-diethylthioxanthone is included among them. 2,4-Diethylthioxanthone is commercially available as KAYACURE-DETX (manufactured by Nippon Kayaku Co., Ltd., product name).

  The (d) thermosetting agent of this invention contains the maleimide compound represented by following General formula (1).

In General Formula (1), R ¹ represents any group selected from an oxygen atom, an alkylene group, and an arylene group, or a divalent organic group containing two or more groups, and R ² and R ³ are each independently An alkyl group, an alkoxy group or a halogen atom is shown, and m and n each independently represent an integer of 1 to 4. When m and n are 2 or more, a plurality of R ² and R ³ may be the same or different.

R ¹ in the general formula (1) is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 6 carbon atoms, and particularly preferably an alkylene group having 1 to 3 carbon atoms. As the arylene group, an arylene group having 6 to 20 carbon atoms is preferable, and an arylene group having 6 to 16 carbon atoms is more preferable. Moreover, as a bivalent organic group containing 2 or more groups chosen from an oxygen atom, an alkylene group, and an arylene group, what is represented by following General formula (3) is preferable.

In General Formula (3), R ⁴ and R ⁵ each independently represent a hydrogen atom or an alkyl group having 1 to 10 carbon atoms, and R ⁶ and R ⁷ each independently represent an alkyl group having 1 to 10 carbon atoms or a carbon number. 1-10 alkoxy group or a halogen atom is shown, p and q show the integer of 0-4 each independently. In general formula (3), when p and q are 2 or more, a plurality of R ⁶ and R ⁷ may be the same or different.

R ⁴ and R ⁵ in the general formula (3) are each preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, and particularly preferably an alkyl group having 1 to 3 carbon atoms. . Moreover, when R < ⁶ > and R < ⁷ > is a C1-C10 alkyl group, a C1-C5 alkyl group is preferable, a C1-C3 alkyl group is more preferable, and a C1-C10 alkoxy In the case of a group, an alkoxy group having 1 to 5 carbon atoms is preferable, and an alkoxy group having 1 to 3 carbon atoms is more preferable.

R ² and R ³ in the general formula (1) are preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, and an alkyl group having 1 to 3 carbon atoms. Is particularly preferred. As an alkoxy group, a C1-C10 alkoxy group is preferable, a C1-C5 alkoxy group is more preferable, and a C1-C3 alkoxy group is especially preferable.

  Among the bismaleimide compounds represented by the general formula (1), a bismaleimide compound represented by the following general formula (4) is particularly preferable.

一般式（４）中、Ｒ^１は酸素原子、アルキレン基、アリーレン基から選ばれるいずれかの基又は２つ以上の基を含む２価の有機基を示し、Ｒ^８、Ｒ^９、Ｒ^１０及びＲ^１１はそれぞれ独立にアルキル基、アルコキシ基又はハロゲン原子を示す。

In General Formula (4), R ¹ represents any group selected from an oxygen atom, an alkylene group, and an arylene group, or a divalent organic group containing two or more groups, and R ⁸ , R ⁹ , R ^10, and R ¹¹ each independently represents an alkyl group, an alkoxy group or a halogen atom.

R ⁸ , R ⁹ , R ¹⁰ and R ¹¹ in the general formula (4) are preferably alkyl groups having 1 to 10 carbon atoms, more preferably alkyl groups having 1 to 5 carbon atoms, and more preferably carbon atoms. 1-3 alkyl groups are particularly preferred. As an alkoxy group, a C1-C10 alkoxy group is preferable, a C1-C5 alkoxy group is more preferable, and a C1-C3 alkoxy group is especially preferable.

  Examples of the bismaleimide compound represented by the general formula (1) include 3,3′-dimethyl-4,4′-diphenylmethane bismaleimide, 3,3′-diethyl-4,4′-diphenylmethane bismaleimide, 3,3 ′, 5,5′-tetramethyl-diphenylmethane bismaleimide, 3,3 ′, 5,5′-tetraethyl-diphenylmethane bismaleimide, 3,3 ′, 5,5′-tetrapropyl-diphenylmethane bismaleimide, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide and the like can be mentioned. Among these, 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide is commercially available as BMI-5000 and BMI-5100 (trade name, manufactured by Daiwa Kasei Co., Ltd.). is there. These can be used alone or in combination of two or more.

  The photosensitive resin composition of the present invention containing the maleimide compound represented by the general formula (1) exhibits particularly excellent sensitivity and resist shape as compared with other maleimide compounds, and has sufficient storage stability. , Surface curability, solder heat resistance, crack resistance, electric corrosion resistance, etc.

  The maleimide compound represented by the general formula (1) according to the present invention is a cyclic curing agent that can be ring-opened by heating and crosslink itself, but the photosensitive resin composition according to the present embodiment is maleimide. An organic peroxide may be further contained as a component for more efficiently starting the above reaction by heating. As the organic peroxide of the present embodiment, it is preferable to select one that generates radicals at a desired temperature at which the thermal polymerization reaction is initiated. For example, t-butylcumyl peroxide, dicumyl peroxide, α, α′-bis (t-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t -Butylperoxy) hexyne-3 and the like. In this embodiment, a drying furnace for producing a photosensitive film or a material having a decomposition temperature lower than the laminator temperature for laminating the film on the substrate, such as azobisisobutyronitrile (AIBN), di-t -Butyl peroxide, acetyl peroxide and the like are not preferable because storage stability and cured properties are deteriorated.

  When the photosensitive resin composition which concerns on this embodiment contains the said organic peroxide, the content is 0.1-10 weight part with respect to 20 weight part of maleimide compounds represented by General formula (1). It is preferable that it is 0.4 to 5 parts by weight. If it is less than 0.1 parts by weight, curing will not be completed in a short time and the cured product tends to be non-uniform, and if it exceeds 10 parts by weight, it will foam during curing or remain due to organic peroxide remaining without decomposition. Hardened physical properties tend to decrease.

  Moreover, the photosensitive resin composition of this invention may contain another compound other than the maleimide compound represented by the said General formula (1) as a (d) thermosetting agent. As other compounds, compounds in which a thermal reaction proceeds at 130 ° C. to 200 ° C. are preferable. For example, epoxy compounds, oxetane compounds, benzoxazine compounds, oxazoline compounds, cyclic carbonate compounds, blocked isocyanates, melamine derivatives, and the like are used. Can do. These are used alone or in combination of two or more.

  Examples of the epoxy compound include bisphenol A type epoxy resins such as bisphenol A diglycidyl ether, bisphenol F type epoxy resins such as bisphenol F diglycidyl ether, bisphenol S type epoxy resins such as bisphenol S diglycidyl ether, and biphenol diglycidyl. Biphenol type epoxy resins such as ether, bixylenol type epoxy resins such as bixylenol diglycidyl ether, hydrogenated bisphenol A type epoxy resins such as hydrogenated bisphenol A glycidyl ether, and dibasic acid-modified diglycidyl ether type epoxies thereof Resin etc. are mentioned. These may be used alone or in combination of two or more.

  Commercially available compounds can be used as these compounds. For example, examples of bisphenol A diglycidyl ether include Epicoat 828, Epicoat 1001, and Epicoat 1002 (all are trade names manufactured by Japan Epoxy Resin Co., Ltd.). Examples of bisphenol F diglycidyl ether include Epicoat 807 (trade name, manufactured by Japan Epoxy Resin Co., Ltd.), and examples of bisphenol S diglycidyl ether include EBPS-200 (trade name, manufactured by Nippon Kayaku Co., Ltd.) and Epicron. EXA-1514 (manufactured by Dainippon Ink & Chemicals, Inc., trade name) and the like can be mentioned. Examples of biphenol diglycidyl ether include YL6121 (trade name, manufactured by Japan Epoxy Resin Co., Ltd.), and examples of bixylenol diglycidyl ether include YX4000H (trade name, manufactured by Japan Epoxy Resin Co., Ltd.). Can do. Furthermore, examples of the hydrogenated bisphenol A glycidyl ether include ST-2004 and ST-2007 (both manufactured by Tohto Kasei Co., Ltd., trade names), and the dibasic acid-modified diglycidyl ether type epoxy resin described above. ST-5100 and ST-5080 (both manufactured by Tohto Kasei Co., Ltd., trade names) and the like can be mentioned. These may be used alone or in combination of two or more.

  Examples of the oxetane compound include all compounds having two or more oxetane rings in one molecule, such as 3-ethyl-3-hydroxymethyloxetane, 1,4-bis {[(3-ethyl-3-oxetanyl )] Methoxy] methyl} benzene, 3-ethyl-3- (2-ethylhexylmethyl) oxetane, 1,4-benzenedicarboxylic acid bis [(3-ethyl-3-oxetanyl) methyl] ester, and the like. Specific examples include the Aron Oxetane series manufactured by Toa Gosei Co., Ltd. and the Etanacol Oxetane series manufactured by Ube Industries, Ltd. These may be used alone or in combination of two or more. When an oxetane compound is used, a curing catalyst such as triphenylphosphine may be used because of low reactivity.

  The block type isocyanate is inactive at room temperature, but when heated, the blocking agent reversibly dissociates to regenerate the isocyanate group. The dissociation temperature of the blocking agent is preferably 120 to 200 ° C. Examples of the isocyanate compound used include isocyanurate type, biuret type, and adduct type, but isocyanurate type is preferable from the viewpoint of adhesion. Examples of the blocking agent include at least one compound selected from diketones, oximes, phenols, alkanols, and caprolactams. Specific examples include methyl ethyl ketone oxime and ε-caprolactam.

  Block type isocyanate is commercially available, for example, Sumidur BL-3175, Desmodur TPLS-2957, TPLS-2062, TPLS-2957, TPLS-2078, BL4165, TPLS2117, BL1100, BL1265, Desmotherm 2170, Desmotherm 2265 (all manufactured by Sumitomo Bayer Urethane Co., Ltd., trade name), Coronate 2512, Coronate 2513, Coronate 2520 (all trade names manufactured by Nippon Polyurethane Industry Co., Ltd.), B-830, B-815, B-846, B -870, B-874, B-882 (all are trade names, manufactured by Mitsui Takeda Chemical Co., Ltd.). These may be used alone or in combination of two or more.

  In particular, when insulating properties are required for the cured resist, it is desirable to include an isocyanuric skeleton or an aromatic ring such as a benzene ring in the structure among the above-described compounds. As such a block type isocyanate, Sumijoule BL-3175, Sumijoule BL-4265 (both manufactured by Sumitomo Bayer Urethane Co., Ltd., trade name), B-870 (made by Mitsui Takeda Chemical Co., Ltd., trade name), etc. Can be mentioned.

  A melamine derivative is an initial condensate obtained by reacting an aldehyde with an amino group-containing compound such as melamine, urea, or benzoguanamine. For example, trimethylol melamine resin, tetramethylol melamine resin, hexamethylol melamine resin, hexamethoxymethyl melamine Melamine resins such as resin, hexabutoxymethyl melamine resin, N, N'-dimethylol urea resin, Cymel 300, Cymel 301, Cymel 303, Cymel 325, Cymel 350, etc. (Mitsui Toatsu Cymel Co., Ltd., melamine resin trade name) Melan resins such as Melan 523, Melan 623, Melan 2000 (manufactured by Hitachi Chemical Co., Ltd., trade name of melamine resin), urea resins such as Melan 18 (manufactured by Hitachi Chemical Co., Ltd., trade name of urea resin), Melan Benzo such as 362A Anamin resin (manufactured by Hitachi Chemical Co., Ltd., the trade name of benzoguanamine resin), and the like. These may be used alone or in combination of two or more. A particularly preferred amino resin includes hexamethoxymethyl melamine resin.

  When the photosensitive resin composition of this embodiment contains other thermosetting agents, the content is preferably 1 to 50 parts by weight with respect to 100 parts by weight of the total amount of component (d) in the present invention. 10 to 40 parts by weight is more preferable, and 15 to 30 parts by weight is particularly preferable. When the content of the component (d) is in such a range, the sensitivity and the resist shape of the photosensitive resin composition become better.

It is preferable that the photosensitive resin composition of this invention further contains an acrylic copolymer as (e) binder polymer from a viewpoint of making a coating-film property and alkali developability more favorable.
The acrylic copolymer can be obtained, for example, by radical polymerization using (meth) acrylic acid and (meth) acrylic acid alkyl ester as a copolymerization component. In particular, a vinyl copolymer compound obtained by using methacrylic acid and (meth) acrylic acid alkyl ester as a copolymerization component is preferable.

  Examples of (meth) acrylic acid alkyl esters include (meth) acrylic acid methyl ester, (meth) acrylic acid ethyl ester, (meth) acrylic acid propyl ester, (meth) acrylic acid butyl ester, (meth) acrylic acid pentyl ester. Examples include esters, (meth) acrylic acid hexyl esters, (meth) acrylic acid heptyl esters, (meth) acrylic acid octyl esters, and (meth) acrylic acid-2-ethylhexyl esters. These can be used alone or in combination of two or more.

  As said vinyl type copolymer compound, you may use what is 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 (meth) acrylic acid tetrahydrofurfuryl ester, (meth) acrylic acid dimethylaminoethyl ester, (meth) acrylic acid diethylaminoethyl ester, methacrylic acid glycidyl ester, 2,2,2- Examples include trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate acrylamide, diacetone acrylamide, styrene, and vinyl toluene. These can be used alone or in combination of two or more.

  The acid value of the binder polymer according to this embodiment is preferably 50 to 170 mgKOH / g, more preferably 70 to 150 mgKOH / g, and 90 to 130 mgKOH / g from the viewpoint of improving alkali developability. More preferably.

  In addition, the weight average molecular weight (Mw) of the binder polymer is preferably 20000 to 150,000 and more preferably 40000 to 120,000 from the viewpoint of improving the coating properties and alkali developability of the photosensitive resin composition. Preferably, it is 50000-100,000. The weight average molecular weight (Mw) can be measured by gel permeation chromatography (GPC) (in terms of standard polystyrene).

  The photosensitive resin composition of this invention can use (f) an inorganic and / or organic filler for the purpose of improving characteristics, such as adhesiveness, hardness, and plating resistance, as needed. Examples of inorganic fillers include inorganic fillers such as barium sulfate, barium titanate, powdered silicon oxide, amorphous silica, talc, clay, calcined kaolin, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica powder. Is mentioned. Examples of the organic filler include diallyl phthalate, diallyl phthalate prepolymer, acrylic rubber, nitrile rubber (NBR), silicone powder, nylon powder, aerosil, benton, and montmorillonite. These can be used alone or in combination of two or more.

  In addition, it is effective to further add an elastomer that is not completely compatible with the acrylic polymer, if necessary, to the photosensitive resin composition of the present invention. By including an elastomer in the photosensitive resin composition, it is possible to improve the adhesion with the conductor layer on the substrate, and further, heat resistance, flexibility and toughness after curing of the photosensitive resin composition. It becomes possible to improve the property. Examples of the elastomer include styrene elastomers, olefin elastomers, urethane elastomers, polyester elastomers, polyamide elastomers, acrylic elastomers, and silicone elastomers.

  In the present invention, it is desirable to use a diluent as necessary. Examples of the diluent include aliphatic alcohols such as methanol, ethanol, n-propanol, i-propanol, n-butanol, n-pentanol and hexanol, hydrocarbons such as benzyl alcohol and cyclohexane, diacetone alcohol, Aliphatic ketones such as 3-methoxy-1-butanol, acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isobutyl ketone, methyl pentyl ketone, methyl hexyl ketone, ethyl butyl ketone, dibutyl ketone, ethylene glycol, diethylene glycol, tri Ethylene glycol, tetraethylene glycol, propylene glycol, ethylene glycol monoacetate, ethylene glycol diacetate, propylene glycol monoacetate, pro Ethylene glycol alkyl ethers such as lenglycol diacetate, propylene glycol monoethyl ether, methyl cellosolve, ethyl cellosolve, butyl cellosolve, phenyl cellosolve, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, methyl cellosolve acetate, ethyl cellosolve acetate And its acetate, diethylene glycol monoalkyl ether and its acetate diethylene glycol dialkyl ether, triethylene glycol alkyl ether, propylene glycol alkyl ether and its acetate, dipropylene glycol alkyl ether, and toluene, petroleum ether, petroleum naphtha, Hydrogenated petroleum naphtha Or petroleum solvents such as solvent naphtha, ethyl formate, propyl formate, butyl formate, amyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, methyl butyrate, ethyl butyrate, etc. Acid esters, amines, amides such as N, N-dimethylformamide, N, N-dimethylacetamide, N-methyl-2-pyrrolidone, dimethyl sulfoxide, dioxane, tetrahydrofuran, cyclohexanone, γ-butyrolactone, 3- Solvents such as hydroxy-2-butanone, 4-hydroxy-2-pentanone, and 6-hydroxy-2-hexanone can be used alone or in combination of two or more.

  Furthermore, the photosensitive resin composition of the present invention can be used as an adhesion improver, for example, when adhesion between the photosensitive resin composition layer and a metal such as copper is required, such as melamine, acetoguanamine, benzoguanamine, and melamine. -Triazine derivatives such as phenol-formalin resin, dicyandiamide, triazine compound, ethyldiamino-s-triazine, 2,4-diamino-s-triazine, 2,4-diamino-6-xylyl-s-triazine, imidazole series, Additives such as thiazole, triazole, and silane coupling agents can be used. 2MZ-AZINE, 2E4MZ-AZINE, C11Z-AZINE, 2MA-OK (both manufactured by Shikoku Kasei Kogyo Co., Ltd.) are available as commercial products. These compounds can improve not only the adhesion between the photosensitive resin composition layer and the metal but also properties such as PCT resistance and electrolytic corrosion resistance.

  The adhesion improver according to this embodiment preferably includes dicyandiamide from the viewpoint of achieving chemical resistance and plating resistance at a higher level. When the photosensitive resin composition of this embodiment contains the said adhesive improvement agent, the content is (a) and (b) component, or when (e) component is contained, (a), (b ) And (e) It is preferable that it is 0.1-10 weight part with respect to 100 weight part of solid content total amount.

  In addition, the photosensitive resin composition of the present invention is phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, malachite green, crystal violet, titanium oxide, carbon black, naphthalene black, azo organic pigment, etc. Colorants or dyes can be used. Furthermore, polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, tert-butylcatechol, pyrogallol and phenothiazine, thixotropic agents such as benton, montmorillonite, aerosil and amide wax, antifoaming agents such as silicone, fluorine and polymer Further, a leveling agent or the like may be included in a range that does not affect the desired characteristics of the photosensitive resin composition.

  Next, suitable content of each component in the photosensitive resin composition which concerns on this embodiment is demonstrated.

  First, the content of component (a) is (a) and (b) component, or when component (e) is included, the total solid content of components (a), (b) and (e) is 100 parts by weight. The amount is preferably 10 to 80 parts by weight, more preferably 25 to 65 parts by weight, and particularly preferably 35 to 55 parts by weight. When the content of the component (a) is in such a range, the coating property of the photosensitive resin composition, the crack resistance of the cured film, and the HAST resistance are further improved.

  The content of component (b) is (a) and (b) component, or when component (e) is included, the total solid content of components (a), (b) and (e) is 100 parts by weight. The amount is preferably 5 to 60 parts by weight, more preferably 10 to 50 parts by weight, and particularly preferably 20 to 40 parts by weight. When the content of the component (b) is in such a range, the sensitivity and the cured film strength become better.

  The content of the component (c) is the component (a) and (b), or when the component (e) is included, the total solid content of the component (a), (b) and (e) is 100 parts by weight. The content is preferably 0.01 to 10 parts by weight, more preferably 0.1 to 5 parts by weight, and particularly preferably 0.5 to 3 parts by weight. When the content of the component (c) is in such a range, the sensitivity and the resist shape become better.

  (D) Content of component is (a) and (b) component, or when (e) component is included, (a), (b) and (e) total solid content of 100 parts by weight of component The amount is preferably 1 to 40 parts by weight, more preferably 5 to 35 parts by weight, and particularly preferably 10 to 30 parts by weight. When the content of the component (d) is in such a range, the solder heat resistance and the plating resistance of the cured film become better.

  When the photosensitive resin composition of this embodiment contains (e) a binder polymer, the content of the component (e) is based on 100 parts by weight of the total solid content of the components (a), (b), and (e). It is preferably 5 to 50 parts by weight, more preferably 10 to 40 parts by weight, and particularly preferably 15 to 35 parts by weight. When the content of the component (e) is in such a range, the coating property and the alkali developability of the photosensitive resin composition become better.

  When the photosensitive resin composition of the present embodiment contains (f) inorganic and / or organic filler, the content is (a) and (b) component, or (e) when component is included (a) ), (B) and (e) The total solid content of 100 parts by weight is preferably 5 to 100 parts by weight, more preferably 20 to 80 parts by weight, and 40 to 60 parts by weight. It is particularly preferred. When the content of the component (f) is in such a range, the hardness and plating resistance of the cured film become better.

  In addition, when using the photosensitive resin composition with a liquid form, it is preferable that content of the diluent used for this invention is 5-40 mass% in the total weight.

  Next, the photosensitive film of suitable embodiment is demonstrated.

  The photosensitive film which concerns on this invention is equipped with a 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 said support body, the polymer film which has heat resistance and solvent resistance, such as a polyethylene terephthalate, a polypropylene, polyethylene, polyester, can be used, for example. 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 before development is peeled off. If it exceeds, the resolution tends to decrease. In addition, you may use the said polymer film by laminating | stacking on the both surfaces of the photosensitive resin composition layer by using one as a support body and another as a protective film.

  As the protective film, for example, a polymer film having heat resistance and solvent resistance such as polyethylene terephthalate, polypropylene, polyethylene, and polyester can be used. Examples of commercially available products include polypropylene film such as product names “Alphan MA-410” and “E-200C” manufactured by Oji Paper Co., Ltd., Shin-Etsu Film Co., Ltd., and product name “PS-” manufactured by Teijin Limited. Polyethylene terephthalate film such as PS series such as “25” can be mentioned, but is not limited thereto. The thickness of the protective film is preferably 1 to 100 μm, more preferably 5 to 50 μm, still more 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. The thickness of the photosensitive layer varies depending on the use, but is preferably 10 to 100 μm, more preferably 15 to 60 μm, and particularly preferably 20 to 50 μm after drying. If this thickness is less than 10 μm, it tends to be difficult to apply industrially, and if it exceeds 100 μm, the sensitivity and resolution inside the photosensitive resin composition layer tend to be reduced.

  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. An end face separator is preferably installed on the end face of the roll-shaped photosensitive film roll from the viewpoint of end face protection, and a moisture-proof end face separator is preferably installed 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).

  Next, a method for forming a resist pattern using the photosensitive film of the present invention will be described.

First, 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, if necessary, a removal process for removing the protective film from the photosensitive film described above is performed, and a predetermined part of the photosensitive resin composition layer is irradiated with actinic rays through the mask pattern, and the photosensitive resin composition of the irradiated part is irradiated. An exposure step for photocuring the layer is performed. At this time, although the exposure process can be performed using a batch exposure type exposure machine, it is preferable to use a direct drawing type LDI type exposure process. When the photosensitive resin composition of the present invention is used, the LDI light source may be either a 355 nm or 405 nm laser beam, and is compatible with i-line and h-line mixed type LDI apparatuses.

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 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. 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 forming 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. For the etching of the metal surface performed after development, for example, a cupric chloride solution, a ferric chloride solution, an alkaline etching solution, or the like can be used.

Next, a preferred embodiment of the photosensitive permanent resist of the present invention using the photosensitive film 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 0.2 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 photosensitive permanent resist formed in this way also serves as a protective film for the wiring after soldering the substrate, and has various characteristics of a solder resist, for printed wiring boards, for semiconductor package boards, flexible wiring boards It can be used as a solder resist.
The solder resist, for example, is used as a plating resist or an etching resist when plating or etching is performed on a substrate, and is also left on the substrate as it is to protect a wiring or the like (photosensitive permanent). Resist).

  Moreover, in the above-described 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 treatment necessary for forming the above-described photosensitive permanent resist.

  The substrate provided with the photosensitive permanent resist of the present invention is then mounted with a semiconductor element or the like (for example, wire bonding, C4 solder connection), and 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 1-6 and Comparative Examples 1-6)
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

  First, about Examples 1-6 and Comparative Examples 1-6, the photosensitive resin composition solution was obtained by mixing each component shown in Table 1 and Table 2 by the compounding quantity (part by weight) shown to the same table. .

  (A) As a photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group, polyurethane compound “UXE-3024” (manufactured by Nippon Kayaku Co., Ltd.) and acid-modified bisphenol F type epoxy acrylate “ZFR-1158” (Nipponization) (Trade name, manufactured by Yakuhin Co., Ltd.) was used. The weight average molecular weight was about 10,000 and the acid value was 70 mgKOH / g.

  (B) As a photopolymerizable monomer having an ethylenically unsaturated group, 2,2-bis (4- (methacryloxypentaethoxy) phenyl) propane “FA-321M” (trade name, manufactured by Hitachi Chemical Co., Ltd.) and Dipentaerythritol hexaacrylate “KAYARAD-DPHA” (trade name, manufactured by Nippon Kayaku Co., Ltd.) was used.

  (C) As a photopolymerization initiator, 1,7-bis (9-acridinyl) heptane “N-1717” (manufactured by Adeka Co., Ltd., trade name) and 2,4-diethylthioxanthone “KAYACURE-DETX” (Nippon Kayaku) (Trade name, manufactured by Co., Ltd.) was used.

  (D) The thermosetting agent is 3,3′-dimethyl-5,5′-diethyl-4,4′-diphenylmethane bismaleimide “BMI-5100” (maleimide compound represented by the above general formula (1)). Daiwa Kasei Co., Ltd. product name) was used.

  Examples of maleimide compounds other than the maleimide compound represented by the general formula (1) include 4,4′-diphenylmethane bismaleimide “BMI-1000” and 2,2-bis [4- (4-N-maleimidinylphenoxy). ) Phenyl] propane “BMI-4000” (both manufactured by Daiwa Kasei Co., Ltd., trade name) was used. As other thermosetting agents, block type isocyanate “BL-3175” (trade name, manufactured by Sumitomo Bayer Urethane Co., Ltd.), methylol melamine “Cymel 300” (trade name, manufactured by Mitsui Toatsu Cymel Co., Ltd.), biphenyl Type epoxy resin “YX4000H” (trade name, manufactured by Japan Epoxy Resin Co., Ltd.) was used.

  (E) A carboxyl group-containing acrylic polymer as a binder polymer, a copolymer of methacrylic acid / methyl methacrylate / butyl acrylate (17/53/30 (weight ratio)), weight average molecular weight 60000, acid value 70 mgKOH Resin (1) which is / g was used.

  (F) Barium sulfate “Variace B-30” (trade name, manufactured by Sakai Chemical Industry Co., Ltd.) was used as an inorganic and / or organic filler, and a barium sulfate dispersion was prepared by the following method.

45 parts by weight of the photosensitive prepolymer solution, 40 parts by weight of barium sulfate, and 50 parts by weight of methyl ethyl ketone were mixed with Starmill LMZ (manufactured by Ashizawa Finetech Co., Ltd.) using zirconia beads having a diameter of 1.0 mm at a peripheral speed of 12 m / s. A barium sulfate dispersion was prepared by dispersing for 3 hours. For the components (a) and (f), the prepared dispersion was used for blending.
In addition, methyl ethyl ketone was added to these photosensitive resin compositions as a diluent, respectively.

＊数値は固形分（重量部）

* Values are solids (parts by weight)

＊数値は固形分（重量部）

* Values are solids (parts by weight)

  Next, a photosensitive resin composition layer is formed by uniformly coating this photosensitive resin composition solution on a 16 μm-thick polyethylene terephthalate film (G2-16, trade name, manufactured by Teijin Ltd.) as a support layer. It was dried for about 10 minutes at 100 ° C. using a hot air convection dryer. The film thickness after drying of the photosensitive resin composition layer was 25 μm.

  Subsequently, on the surface of the photosensitive resin composition layer opposite to the side in contact with the support, a polyethylene film (NF-15, manufactured by Tamapoly Co., Ltd., trade name) is bonded as a protective film, and is photosensitive. A film was obtained.

[Evaluation of sensitivity]
The copper surface of a printed wiring board substrate (E-679, manufactured by Hitachi Chemical Co., Ltd., trade name) obtained by laminating a 12 μm thick copper foil on a glass epoxy substrate was polished with an abrasive brush, washed with water, and dried. On this printed wiring board substrate, using a continuous press type vacuum laminator (MVLP-500, manufactured by Meiki Seisakusho Co., Ltd., trade name), press hot plate temperature 70 ° C., evacuation time 20 seconds, laminating press time 30 seconds. The protective film of the photosensitive film was peeled off and laminated under the conditions of an atmospheric pressure of 4 kPa or less and a pressure bonding pressure of 0.4 MPa to obtain a laminate for evaluation.

  Then, after standing at room temperature (25 ° C.) for 1 hour or longer, a 21-step tablet (manufactured by Eastman Kodak Co.) was brought into close contact with the support of the obtained laminate for evaluation, and a wavelength using a YAG laser as a light source. Exposure was performed using an LDI direct drawing exposure machine Paragon 9000 (manufactured by Orbotech) that irradiates a 355 nm actinic ray.

After exposure, the film was allowed to stand at room temperature for 30 minutes, and then the polyethylene terephthalate on the support was removed, and the photosensitive resin composition in the unexposed area was spray-developed with a 1% by mass aqueous sodium carbonate solution at 30 ° C. for 60 seconds.
After development, the exposure energy amount at which the number of remaining steps of the 21-step tablet was 8.0 was defined as the sensitivity (unit: mJ / cm ² ) of the photosensitive resin composition layer. A lower value indicates higher photosensitivity.

[Evaluation of resist shape]
The evaluation laminate obtained in the same manner as in the sensitivity evaluation described above was allowed to stand at room temperature for 1 hour or longer, and then digital data having an opening pattern with a diameter of 80 μm was subjected to 21 steps using a Paragon 9000 type exposure machine manufactured by Orbotech. Drawing exposure was directly performed on the support of the laminate for evaluation with an energy amount such that the number of remaining steps of the tablet was 8.0.

After exposure, it is allowed to stand at room temperature for 30 minutes to remove the polyethylene terephthalate on the support, and the photosensitive resin composition in the unexposed area with a 1% by mass aqueous sodium carbonate solution at 30 ° C. is subjected to a minimum development time (the unexposed area is developed). Spray development for 1.5 times the minimum time. After spray development, UV irradiation of 1 J / cm ² is performed using an ultraviolet irradiation device manufactured by Oak Manufacturing Co., Ltd., and further subjected to heat treatment at 160 ° C. for 60 minutes to form a permanent mask resist pattern having an opening with a diameter of 80 μm. Formed.

  Subsequently, the cross section in the opening part with a diameter of 80 micrometers of the resist pattern was observed using the S-2100A scanning electron microscope by Hitachi, Ltd. The resist shape of the opening should be a “forward taper” shape as shown in FIG. 1A or a “straight” shape as shown in FIG. 1B from the viewpoint of solder adhesion. Is desirable. The bottom of the resist elutes during development due to insufficient exposure, such as “undercut” as shown in FIG. 1C, and the upper portion of the resist remains due to overexposure, such as “overhang” as shown in FIG. The reverse taper shape is not preferable because the solder adhesion may be deteriorated during soldering. 1 shows a printed wiring board substrate having a permanent mask resist pattern 1 formed by providing a solder resist 10 having openings 13 formed on a glass epoxy base material 12 having a conductor layer 11. A schematic sectional view is shown.

  In the evaluation of the resist shape, the case where the cross-sectional shape of the resist opening is a forward tapered shape or a straight shape shown in FIG. 1 (a) or (b) is evaluated as “◯”, and FIG. 1 (c) or (d) An overhang or undercut as shown in FIG.

[Storage stability]
The prepared photosensitive film is packed with a light-shielding black sheet, left at 23 ° C. for 20 days, and then subjected to exposure, development, UV irradiation, and a heating process under the same conditions as in the above resist shape evaluation to form a permanent mask resist pattern. They were formed, observed with a stereomicroscope and evaluated according to the following criteria. That is, “o” indicates that no resin residue is observed in the unexposed area, and “x” indicates that resin residue is observed in the unexposed area.

[Evaluation of surface hardness]
The pencil hardness of the surface of the permanent mask resist pattern obtained in the same manner as the evaluation of the resist shape was measured according to JIS K5600-5-4, and the presence or absence of a flaw on the resist surface was visually observed. A 4H hardness pencil (Mitsubishi Pencil Co., Ltd.) was used for the measurement. The evaluation of the surface hardness is “O” when the resist surface is not scratched at 4H, that is, when the pencil hardness is 4H or more, and when the resist surface is scratched at 4H, that is, the pencil hardness is 3H or less. Some were marked as “x”.

[Evaluation of solder heat resistance]
The evaluation laminate obtained in the same manner as in the above sensitivity evaluation was allowed to stand at room temperature for 1 hour or longer, and then the digital data having a 2 mm square opening pattern was subjected to 21 steps using a Paragon 9000 type exposure machine manufactured by Orbotech. Drawing exposure was directly performed on the support of the laminate for evaluation with an energy amount such that the number of remaining steps of the tablet was 8.0.
Subsequently, after leaving still at room temperature for 1 hour, the polyethylene terephthalate on this laminated body was peeled, and it was 1. Spray development took 5 times longer. After spray development, UV irradiation of 1 J / cm ² is performed using an ultraviolet irradiation device manufactured by Oak Manufacturing Co., Ltd., and heat treatment is further performed at 160 ° C. for 60 minutes to form a solder resist having a 2 mm square opening. An evaluation board was obtained.

  Next, rosin-based flux (MH-820V, manufactured by Tamura Kaken Co., Ltd., trade name) was applied to the evaluation substrate, and then immersed in a solder bath at 260 ° C. for 10 seconds. This treatment was performed once, and the soldering treatment was performed three times in total.

  On the evaluation substrate thus plated with solder, the state of solder resist cracking and the presence or absence of solder resist floating and peeling from the substrate were observed with a 100-fold metal microscope and evaluated according to the following criteria. That is, the case where no crack was observed in the solder resist and the solder resist was not lifted or peeled off was indicated as “◯”, and the case where any of them was recognized as “X”.

[Evaluation of crack resistance]
After the evaluation substrate on which the permanent mask resist obtained in the same manner as the evaluation of the solder heat resistance was formed was exposed to the atmosphere of −65 ° C. for 15 minutes, the temperature was increased at a temperature increase rate of 180 ° C./min. After being exposed to the atmosphere at 150 ° C. for 15 minutes, a heat cycle in which the temperature was lowered at a rate of 180 ° C./min was repeated 100 times. After the test, the cracks and the degree of peeling of the permanent resist film on the evaluation substrate were observed with a 100-fold metal microscope and evaluated according to the following criteria. That is, “◯” indicates that no crack or peeling of the permanent resist film was observed, and “X” indicates that any of them was confirmed.

[Evaluation of HAST resistance]
Etching is applied to the copper surface of a printed wiring board substrate (E-679, manufactured by Hitachi Chemical Co., Ltd., trade name) in which a 12 μm-thick copper foil is laminated on a glass epoxy substrate, and the line / space is 50 μm / 50 μm. A comb electrode was formed. Using this substrate as an evaluation substrate, a permanent mask resist was formed on the substrate in the same manner as in the evaluation of solder heat resistance, and the substrate was exposed to conditions of 130 ° C., 85% RH, and 20 V for 100 hours. After the test, the degree of migration was observed with a 100 × metal microscope and evaluated according to the following criteria. That is, “O” indicates that no migration occurred in the permanent resist film, and “X” indicates that migration occurred. 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.
The results are shown in Tables 3 and 4.

  As is apparent from Table 3, Examples 1 to 6 are good in sensitivity, resist shape and storage stability. Furthermore, when a polyurethane compound is included as a photosensitive prepolymer having (a) a carboxyl group and a photopolymerizable unsaturated group as in Examples 1, 3, and 5, more excellent sensitivity can be obtained. On the other hand, as apparent from Table 4, Comparative Examples 1 to 6 are insufficient in sensitivity, resist shape, or storage stability. Therefore, according to the photosensitive resin composition of the present invention, excellent sensitivity and resist shape and sufficient storage stability can be obtained even when applied to the LDI system.

It is a schematic sectional drawing which shows the opening part of the photosensitive permanent resist which concerns on this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Photosensitive permanent resist, 10 ... Solder resist, 11 ... Conductor layer, 12 ... Glass epoxy base material, 13 ... Opening part

Claims (7)

(A) A photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group, (b) a photopolymerizable monomer having an ethylenically unsaturated group, (c) a photopolymerization initiator, and (d) a thermosetting agent A photosensitive resin composition comprising:
(A) The photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group is an epoxy acrylate compound having two or more hydroxyl groups and an ethylenically unsaturated group in the molecule, a diisocyanate compound, and a diol having a carboxyl group Containing a polyurethane compound obtained by reacting a compound,
The photosensitive resin composition in which the said (d) thermosetting agent contains the maleimide compound represented by following General formula (1).

(In the general formula (1), R ¹ represents any group selected from an oxygen atom, an alkylene group, and an arylene group or a divalent organic group containing two or more groups, and R ² and R ³ are each independently selected. Represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, or a halogen atom, and m and n each independently represent an integer of 1 to 4. When m and n are 2 or more, A plurality of R ² and R ³ may be the same or different.)   (E) The photosensitive resin composition of Claim 1 which further contains an acrylic copolymer as a binder polymer. The photosensitive resin composition of Claim 1 or 2 in which the said (c) photoinitiator contains an acridine derivative. A photosensitive film comprising: a support; and a photosensitive resin composition layer comprising the photosensitive resin composition according to any one of claims 1 to 3 formed by applying and drying the support. . A photosensitive resin composition layer comprising the photosensitive resin composition according to any one of claims 1 to 3 is provided on a circuit forming substrate, and the photosensitive resin composition layer is irradiated with actinic rays in an image form. Then, the exposed portion is photocured, and the unexposed portion is removed by development. A photosensitive resin composition layer comprising the photosensitive resin composition according to any one of claims 1 to 3 is provided on a circuit forming substrate, and an active ray is applied directly to the photosensitive resin composition layer by a drawing method. A method for forming a resist pattern, wherein the exposed portion is irradiated with an image to photocure the exposed portion and the unexposed portion is removed by development. Permanent resist formed by the method of forming a resist pattern according to claim 5 or 6.

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