JP2001228610A - Photosensitive resin composition and method for producing cured film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a soldering resist or an interlayer insulation material capable of forming an image by short-time exposure with UV by the concomitant use of photo radical polymerization and cationic polymerization and subsequent development with a dilute aqueous alkali solution, capable of completing cationic polymerization and crosslinking with an alkali-soluble resin by short- time heating by the action of a cationic polymerization initiator in the presence of a compound having an oxetane structure after pattern formation and excellent in various characteristics such as adhesion, soldering resistance, pressure cooker resistance and low water absorbing property. SOLUTION: This invention relates a photosensitive resin composition containing an alkali-soluble resin (A), a compound (B) having an oxetane structure, a compound (C) having a radical polymerizable unsaturated group, a photo radical initiator (D) and a cationic polymerization initiator (E), a cured film of the composition and a method for curing the composition.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photosensitive resin composition used in a printed circuit board manufacturing process and a method for obtaining a cured film using the same. The present invention relates to a photosensitive resin composition which can form an image, has high sensitivity, and is cured by a short heat treatment after pattern formation, and a method for producing a cured film using the same.

[0002]

2. Description of the Related Art In recent years, with the miniaturization and high performance of electronic equipment, fine patterns of printed wiring boards have been developed.
As for the material used for the solder resist, a material capable of finer processing has been required.

[0003] Solder resist is used to form a film on the front surface of a circuit conductor excluding a portion to be soldered. When soldering an electronic component to a printed wiring board, solder resist is used at a portion where soldering is unnecessary. In addition to preventing adhesion, it also functions as a protective film for preventing the circuit conductor from being directly exposed to air and corroded by oxidation or humidity.

Conventionally, the solder resist has been mainly formed by forming a pattern on a substrate by a screen printing method and curing it by ultraviolet rays or heat. However, high resolution and high precision are required. Accordingly, the liquid photo solder resist method has been attracting attention regardless of whether it is a consumer substrate or an industrial substrate.

A liquid photo solder resist method using a solder resist composition comprising, for example, a bisphenol type epoxy acrylate resin, a sensitizer, an epoxy compound, an epoxy curing agent, and the like has been disclosed in Japanese Patent Application Laid-Open No. Sho 50-14443.
No. 1 and Japanese Patent Publication No. 51-40451. How to use these solder resist compositions,
The coating was applied on the entire surface of the printed wiring board, the organic solvent was volatilized and then exposed, and then the unexposed portion was removed by using an organic solvent to develop. However, with the recent problem of environmental pollution, especially the VOC problem, it is considered that there is a limit to the method of developing using a large amount of organic solvent.

As a solution in the above situation, an alkali developing type photo solder resist that can be developed with a dilute alkaline aqueous solution has been proposed, and has become mainstream from the viewpoint of preserving the working environment and preventing pollution. These are, for example, those obtained by reacting an unsaturated monocarboxylic acid with an epoxy resin and further adding a polybasic acid anhydride to obtain a base polymer (JP-A-56-40329, JP-A-57-40329). 457
No. 85, JP-A-61-243869), using an active energy ray-curable resin obtained by reacting a saturated or unsaturated polybasic anhydride with a reaction product of a novolak type epoxy resin and a monocarboxylic acid. What was (Tokuhei 1-5
No. 4390) is known.

Further, in recent years, demands for higher density printed wiring boards have increased the demand for multilayer wiring boards in which a plurality of conductive wiring boards are stacked via an insulating layer. As the insulating layer, a method of laminating a conductor circuit using an alkali-developable photosensitive composition (Japanese Patent Application Laid-Open No. 4-148590,
JP-B-4-55555, JP-A-6-317904
And the photosensitive resin composition of the present invention can be used in the same manner.

A composition for forming a permanent resist film such as a solder resist or an interlayer insulating film is composed of an alkali-soluble resin, a radically polymerizable compound, a photoradical initiator, an epoxy compound and / or an amine compound. Are used as follows. First, the composition is applied to a substrate to a constant thickness, and then prebaked to remove the solvent. A mask on which a pattern is formed is placed on the coating film, and is exposed by irradiating a certain energy light. At this time, the radically polymerizable compound is polymerized, crosslinked and cured. Next, the unexposed portion is washed with a caustic alkali or the like, and the alkali-soluble resin is dissolved and developed. The substrate is further washed with pure water or the like and then dried. Further, this coating film is subjected to after-baking at a high temperature of 150 to 200 ° C. to react or recrosslink an epoxy or amine with an alkali-soluble site, thereby forming a tough cured film.

Such a photosensitive resin composition has a problem that a long-time treatment at a high temperature is required in the final curing step. In addition, a film formed using this composition does not sufficiently satisfy the required performance with respect to water resistance and heat resistance, and further has a problem that curing shrinkage is large, pattern shift and adhesion are poor.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is possible to form an image by short-time ultraviolet exposure using a combination of photoradical polymerization and cationic polymerization, followed by development with a dilute aqueous alkali solution. After pattern formation, in the presence of a compound having an oxetane structure,
Due to the action of the cationic polymerization initiator, the cationic polymerization and crosslinking with the alkali-soluble resin can be completed by a short heat treatment, and are excellent in various properties such as adhesion, solder resistance, pressure cooker resistance and low water absorption. Alternatively, an interlayer insulating material is provided.

[0011]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, have found that the problems can be solved by a specific photosensitive resin composition portion, and have completed the present invention. Was. That is, the present invention relates to the following matters. [1] A photosensitive composition comprising a compound (A) having an oxetane structure, a compound (B) having a radically polymerizable unsaturated group, a photoradical initiator (C), and a cationic polymerization initiator (D). Resin composition. [2] The photosensitive resin composition according to the above [1], which contains an alkali-soluble resin (E). [3] The photosensitive resin composition according to the above [1] or [2], which contains a compound (F) having an epoxy group. [4] The above-mentioned [1] to [3], wherein as the compound (A) having an oxetane structure, a compound having at least one alicyclic structure other than an oxetane ring is used alone or in combination of two or more. The photosensitive resin composition according to any one of the above. [5] The compound (A) having an oxetane structure is represented by the formula (1)

[0012]

Embedded image

Wherein m is an integer of 0 to 2 and n is 0
Is 2 in the above case, and 1 in other cases, and X represents a hydrogen atom or a methyl group. ] The photosensitive resin composition according to any one of the above [1] to [4], which is a compound represented by the formula: [6] As compound (A) having an oxetane structure, 2
-Oxaspiro [3.5] nonane, 7-methyl-2-oxaspiro [3.5] nonane, spiro [bicyclo [2.
2.1] Heptane-2,3'-oxetane], 5-methyl-2-oxaspiro [3.5] nonane, spiro [3-
The method according to any one of the above-mentioned [1] to [5], wherein one or more kinds selected from the group consisting of methylbicyclo [2.2.1] heptane-2,3′-oxetane] are used. Photosensitive resin composition. [7] The photosensitive resin composition according to any one of [1] to [6], wherein the compound (A) having an oxetane structure is used in an amount of 1 to 50 parts by weight based on 100 parts by weight of the alkali-soluble resin (E). .

[8] The photosensitive resin composition according to any one of the above [1] to [7], which is used as a resist material. [9] A cured film obtained by curing the photosensitive resin composition according to any one of [1] to [8]. [10] A cured solder resist film comprising the cured film according to the above [9]. [11] An interlayer insulating cured film for a multilayer wiring board comprising the cured film according to the above [9]. [12] In the formation of a cured film, the photosensitive resin composition according to any one of the above [1] to [8] is used to cure the radical polymerizable compound and cation polymerize the compound during light irradiation. A method for producing a cured film, wherein part or all of the film is cationically cured.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in more detail. The present invention relates to a photosensitive resin composition containing a compound (A) having an oxetane structure, a compound (B) having a radically polymerizable unsaturated group, a photoradical initiator (C), and a cationic polymerization initiator (D). .

As the compound (A) having an oxetane structure used in the present invention, 3-ethyl-3-hydroxymethyloxetane (manufactured by Toagosei Co., Ltd .; trade name: EO)
XA), bis [(3-ethyl-3-oxetanylmethoxy) methyl] benzene (also known as xylylenedioxetane;
Toagosei Co., Ltd .; trade name XDO), tri [(3-ethyl-3-oxetanylmethoxy) methyl] benzene,
Bis [(3-ethyl-3-oxetanylmethoxy) methylphenyl] ether, (3-ethyl-3-oxetanylmethoxy) oligodimethylsiloxane, a compound having a high-molecular-weight polyvalent oxetane ring, specifically an oxetane oligomer ( Toagosei Co., Ltd .; trade name Oligo
-OXT) and the like.

In addition to the oxetane ring, those having an alicyclic structure in the same compound include 2-oxaspiro [3.5] nonane, 7-methyl-2-oxaspiro [3.5] nonane, spiro [adamantane] −2,3′-
Oxetane], spiro [bicyclo [2.2.1] heptane-2,3'-oxetane], spiro [bicyclo [2.
2.2] octane-2,3'-oxetane], spiro [7-oxabicyclo [2.2.1] heptane-2,
3'-oxetane], 2-oxaspiro [3.5] non-6-ene, 5-methyl-2-oxaspiro [3.5]
Nona-6-ene, spiro [bicyclo [2.2.1] hept-5-ene-2,3'-oxetane], spiro [3-
Methylbicyclo [2.2.1] hept-5-ene-2,
3'-oxetane], 5-methyl-2-oxaspiro [3.5] nonane, spiro [3-methylbicyclo [2.
2.1] heptane-2,3'-oxetane].

A cured film formed from the resin composition containing the compound (A) having an oxetane structure has low water absorption, and as a result, exhibits excellent water resistance.
In addition, since the degree of shrinkage upon curing is small, the pattern has excellent adhesion and dimensional stability after exposure and development. Among them, compounds having an alicyclic structure in the same compound other than the oxetane ring are preferable from the viewpoint of water resistance,
In particular, 2-oxaspiro [3.5] nonane, spiro [bicyclo [2.2.1] heptane-2,3'-oxetane], 5-methyl-2-oxaspiro [3.5] nonane, spiro [3-methyl Bicyclo [2.2.1] heptane-2,3'-oxetane] is preferred.

These compounds (A) having an oxetane structure can be used alone or as a mixture of two or more. A suitable range for the amount used is 1 to 50 parts by mass, preferably 5 to 40 parts by mass, per 100 parts by mass of the alkali-soluble resin (E). If the amount is less than 1 part by mass, the physical properties of the coating film are inferior, which is not preferable. On the other hand, if the amount exceeds 50 parts by mass, the dryness to the touch deteriorates and the developability also decreases, which is not preferable.

The compound (B) having a radically polymerizable unsaturated group is not particularly limited, and known and commonly used photopolymerizable monomers can be used. Specifically, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) ) Acrylate, phenoxyethyl (meth) acrylate,
2-ethoxyethyl (meth) acrylate, glycidyl (meth) acrylate, 2-hydroxyethyl (meth)
Monofunctional (meth) acrylate compounds such as acrylate, benzyl (meth) acrylate, and ethylene glycol mono (meth) acrylate; ethylene glycol di (meth) acrylate, polyethylene glycol di (meth)
Examples include acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and polyfunctional epoxy (meth) acrylate.

The purpose of using the above-mentioned photopolymerizable monomer is to dilute the photosensitive composition so as to make it easy to apply and to impart radical polymerizability. In particular, when an alkali-soluble resin (E) to which a radical polymerizable group is not provided is used, the photopolymerizable monomer is an essential component.

The amount of the compound (B) having a radically polymerizable unsaturated group is 3 to 50 parts by mass based on 100 parts by mass of the alkali-soluble resin (E). If the amount exceeds 50 parts by mass, the dryness to the touch is reduced, which is not preferable.

In the present invention, the photo-radical initiator (C)
A known and commonly used substance which generates radicals in response to light can be used. Here, "light" means visible light, ultraviolet light,
It means radiation such as far ultraviolet rays, X-rays and electron beams.

Examples of the photo radical initiator (C) include benzoin, benzoin ethyl ether, benzoin isopropyl ether, benzoin-n-butyl ether, benzoin isobutyl ether, acetophenone,
Dimethylaminoacetophenone, 2,2-dimethoxy-
2-phenylacetophenone, 2,2-diethoxy-2
-Phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- [4
-(Methylthio) phenyl] -2-morpholinopropan-1-one (manufactured by Ciba Specialty Chemicals, Inc .; Irgacure 907), 4- (2-hydroxyethoxy) phenyl-2- (hydroxy-2-propyl) ketone, benzophenone , P-phenylbenzophenone,
4,4′-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-t-butylanthraquinone, 2-aminoanthraquinone, 2-
Methylthioxanthone, 2-ethylthioxanthone, 2
-Chlorothioxanthone, 2,4-diethylthioxanthone, benzyldimethylketal, p-dimethylaminebenzoic acid ester, 2,4,6-trimethylbenzoyldiphenylphosphine oxide (manufactured by BASF; Lucirin TPO), bis (2,6- Dimethoxybenzoyl) -2,4,4-trimethyl-pentylphosphine oxide-containing initiator (manufactured by Ciba Specialty Chemicals Co., Ltd .; Irgacure 1700, 149, 180)
0), bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (manufactured by Ciba Specialty Chemicals, Inc .; Irgacure 819). These can be used alone or as a mixture of two or more.

The amount of the photo-radical initiator (C) used is 0.1 to 1 equivalent of (meth) acryl of the alkali-soluble resin (E) and the compound (B) having a radical polymerizable unsaturated group.
007 to 0.36 mol, preferably 0.035 to 0.2
Is a mole. If the amount of the photo-radical initiator is less than 0.007 mol, the sensitivity becomes poor. On the other hand, if it exceeds 0.36 mol, the sensitivity is not improved, and it is not economically preferable.

As the cationic polymerization initiator (D), known iodonium salts, sulfonium salts, phosphonium salts, ferrocenes and the like can be used. Specific examples include diphenyliodonium hexafluoroantimonate, diphenyliodonium hexafluorophosphate, diphenyliodonium hexafluoroborate, triphenylsulfonium hexafluoroantimonate, triphenylsulfonium hexafluorophosphate, and triphenylsulfonium hexafluoroborate. However, the present invention is not particularly limited to these. Commercially available cationic polymerization initiators (D) include SP-150 and SP-17 manufactured by Asahi Denka Kogyo KK
0, CP-66, CP-77; CI manufactured by Nippon Soda Co., Ltd.
-2855, CI-2639; Sanshin Chemical Industry Co., Ltd. Sun Aid SI-60 and the like are available. These can be used alone or as a mixture of two or more. For example, CYRACURE-UVI manufactured by Union Carbide Co., Ltd.
Some are commercially available as mixtures, such as -6990 and UVI-6974, and can be used in the same manner as the above compounds.

The preferred range of the amount of the cationic polymerization initiator (D) used is 0.05 to 25% by mass, preferably 1 to 10% by mass, based on the total amount of the oxetane compound (A) and the epoxy compound (F) described later. % By mass. If the added amount is less than 0.05%, the sensitivity becomes poor, and even if added over 25% by mass, the sensitivity is not improved, which is not economically preferable.

The alkali-soluble resin (E) used in the present invention is not particularly limited as long as it is soluble in an aqueous alkali solution and can form a film. Specifically, vinylphenol polymer, vinylphenol and other monomers having a copolymerizable double bond (for example, esters such as methyl (meth) acrylate, hydroxyethyl (meth) acrylate; Acid amides such as (meth) acrylamide; acrylonitrile; styrene, etc.), novolak resins which are polycondensates of phenols and aldehydes, or partially hydrogenated products of these resins, Acrylic acid and other monomers having a copolymerizable double bond (eg, esters such as methyl (meth) acrylate, hydroxyethyl (meth) acrylate; acid amides such as (meth) acrylamide; acrylonitrile And styrene, etc.).

The alkali-soluble resin may be provided with a radical polymerizable group. Specifically, JP-A-3-71137, JP-A-9-136942, and JP-A-10-274849. JP-A-11-24254 describes a resin in which an unsaturated monocarboxylic acid such as acrylic acid is reacted with a part of epoxy groups of a novolak-type epoxy resin and then reacted with a polybasic anhydride. A resin obtained by reacting (meth) acrylic acid with a part of epoxy groups of such a polyfunctional epoxy resin and further reacting glycidyl (meth) acrylate with a carboxyl group generated by reacting a polybasic anhydride, Glycidyl (meth) is used to form a part of the hydroxyl groups of phenolic resin, novolak phenolic resin or phenoxy resin by a standard method.
A known material such as a resin to which acrylate is added can be used. These alkali-soluble resins can be used alone or
It can be used in mixtures of more than one species.

As the epoxy compound (F) used in the present invention, known and commonly used epoxy compounds can be used, and there is no particular limitation as long as the compound has two or more epoxy groups in one molecule. Specifically, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak epoxy resin, cresol novolak epoxy resin, bisphenol A-novolak type epoxy resin, bisphenol type epoxy resin, triglycidyl isocyanurate and the like can be used. . Further, as the alicyclic epoxy compound, 4-vinylcyclohexene diepoxide, (3,4-epoxycyclohexyl)
Methyl-3,4-epoxycyclohexylcarboxylate, di (3,4-epoxycyclohexyl) adipate, bis (2,3-epoxycyclopentyl) ether, di (2,3-epoxy-6-methylcyclohexylmethyl) adipate, Cyclopentadienedioxide and the like can be mentioned.

These epoxy resins can be used alone or in combination of two or more. The preferred range of the amount of the epoxy resin used is preferably 1 to 100 parts by mass, and more preferably 20 to 70 parts by mass with respect to 100 parts by mass of the alkali-soluble resin (E).
Part by weight is particularly preferred.

The photosensitive resin composition of the present invention may contain an organic solvent. The intended use of organic solvents is
The photosensitive composition is dissolved and diluted, whereby the photosensitive composition can be applied in a liquid state, and then is preliminarily dried to form a film, thereby enabling contact exposure. Specifically, for example, ethylene glycol monoalkyl ether or acetates thereof; diethylene glycol mono or dialkyl ethers; propylene glycol monoalkyl ether or acetates thereof; dipropylene glycol mono or dialkyl ethers; methyl carbitol, butyl carbitol; Butyl cellosolve acetate, carbitol acetate, ethyl methyl ketone, cyclohexane, toluene, xylene, tetramethylbenzene, petroleum ether,
Known organic solvents such as petroleum naphtha and solvent naphtha;
Or additives and solvents well known in the art, such as plasticizers, may be used, and these may be used alone or in combination of two or more.

The amount of the organic solvent to be added is 10 to 300 parts by mass with respect to 100 parts by mass of the alkali-soluble resin (E), and can be appropriately selected according to the coating method. The photosensitive resin composition of the present invention, for the purpose of improving properties such as adhesion and hardness, if necessary, further barium sulfate, barium titanate, silicon oxide powder, finely divided silicon oxide, amorphous silica, talc, Known and commonly used inorganic fillers such as clay, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide, and mica powder can be used. Its usage is
It is preferably from 0 to 150% by mass, more preferably from 20 to 100% by mass, based on the total amount of the photosensitive resin composition.

If necessary, known and conventional coloring agents such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black and naphthalene black; silicone-based, fluorine-based, and polymer A known and commonly used additive such as an antifoaming agent and / or a leveling agent such as an imidazole-based, thiazole-based, triazole-based, and silane coupling agent can be used.

The application of the heat-sensitive resin composition of the present invention includes paints, adhesives, printing inks, can coatings, plastic coatings, sealants, casting materials, three-dimensional molding, solder resists, interlayer insulating films for multilayer printed wiring boards. And the like. Further, when the photosensitive resin composition of the present invention is used for a solder resist or an insulating film for a multilayer printed wiring board, etc., when performing pattern development after exposure with an aqueous alkali solution, by using an alkali-soluble resin together. It is preferably used. Further, a cured film using the photosensitive resin composition of the present invention is a paint, an adhesive,
It is suitably used for printing ink, can coating, plastic coating, sealant, casting material, three-dimensional molding, resist, interlayer insulating film for multilayer printed wiring boards, and the like.

In the present invention, as a method for obtaining a cured product using the photosensitive resin composition, the following method is exemplified. That is, the screen printing method,
After applying the composition of the present invention in a thickness of 10 to 200 μm by a method such as a spray method, a roll coating method, an electrostatic coating method, and a curtain coating method, and drying the coating film at 60 to 100 ° C. for 5 to 60 minutes, The negative film is brought into direct contact with the coating film and then irradiated with ultraviolet light to cure the radically polymerizable compound and cationically cure part or all of the cationically polymerizable compound, and to cure the unexposed portion with a dilute alkaline aqueous solution (eg, , Sodium hydroxide, potassium hydroxide, sodium carbonate, sodium silicate, ammonia, triethylamine, tetramethylammonium hydroxide, etc.)
After dissolving and removing with
Heat curing at 50 ° C. for 20 to 180 minutes to obtain a cured film. If desired, ultraviolet rays or the like may be irradiated before and after the final heating.

In the present invention, as a method of curing the cured film, a general treatment method can be adopted. In the case of patterning by exposure to ultraviolet rays or the like, acrylic polymerization and cationic polymerization are used in combination. In this case, it is characterized in that it is rapidly cured by cationic polymerization. Thereby, the final heat treatment can be completed in a shorter time than in the case of patterning using conventional acrylic polymerization alone, and the obtained cured film has excellent physical properties.

[0038]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

The coating properties (adhesion, solder resistance, pressure cooker test (PC
T) and water absorption) were evaluated according to the following methods. In preparing the coating film, the photosensitive resin composition was applied to a surface-treated substrate in advance by a screen printing method.
m (before drying), and after pre-drying at 80 ° C. for 20 minutes, a negative mask (Contact Control Gu
ide, C-3) was brought into close contact with the coating surface, irradiated with ultraviolet light at an exposure of 400 mJ / cm ² , and then developed with a 1% by mass aqueous solution of sodium carbonate at a spray pressure of 2.0 kg / cm ² for 60 seconds. Thereafter, post-curing was performed at 150 ° C. for 20 minutes to obtain a cured coating film. The following tests were performed on the obtained cured coating films.

1) Resolution 100 of KODAC (Contact Control Guide C-3)
The pattern of μm was observed under a microscope of 20 to 100 times magnification. ：: The pattern does not fall off and the boundary between the line and the space is clear. ×: The pattern is dropped or the boundary between the line and the space is unclear.

2) Adhesion test According to JIS D0202, a cross cut was made in a grid pattern, and the peeling state after a peeling test using a cellophane tape was visually observed. ：: 100/100 (no change at all) ×: 0/100 to 99/100

3) Solder Resistance Test Based on JIS C6481 method, the state after immersion in a solder bath at 260 ° C. for 15 seconds three times and the adhesion were comprehensively evaluated. ◎: No change observed ○: Slight change Δ: Notable change ×: Swelling or swelling-off of coating film

4) Pressure Cooker (PCT) Resistance The substrate on which the solder resist film was formed was subjected to a pressure cooker tester (Hirayama Seisakusho; PC-422R).
III), left for 150 hours under the conditions of 121 ° C., 2 atm and 100% saturation, taken out, and visually observed the peeling state after the peeling test with a cellophane tape.

5) Measurement of Water Absorption A photosensitive resin composition was applied to a 4-inch diameter silicon wafer having a measured mass W ₀ by spin coating, and the temperature was 80 ° C.
For 30 minutes, and exposed to ultraviolet light of 400 mJ / cm ² , and then heat-treated at 150 ° C. for 30 minutes. The mass was measured W ₁ of the test substrate obtained here. Subsequently, the test substrate was immersed in ultrapure at room temperature for 24 hours, and then the test substrate was sufficiently wiped with filter paper to remove the substrate weight W _2.
Was measured. The water absorption (%) was calculated according to the following equation. Water absorption (%) = (W ₂ −W ₁ ) / (W ₁ −W ₀ ) × 100

<Production Example> One mole of acrylic acid is reacted with 1 mole of epoxy equivalent of cresol novolac type resin (manufactured by Nippon Kayaku Co., Ltd .; EOCN-102S) in a usual manner using 30% by mass of butylcellosolve acetate as a solvent. Then, an epoxy acrylate was obtained. 0.5 mol of tetrahydrophthalic anhydride was reacted with the monohydric equivalent of the epoxy acrylate until the acid value reached the theoretical value.

Examples 1 to 6 The components shown in Table 1 were blended and kneaded with a roll mill to obtain a photosensitive resin composition. The numerical values in the table indicate the number of copies. After forming the coating film, resolution, adhesion, solder resistance, pressure cooker test (PC
Each test of T) and water absorption was performed. The results are shown in Table 1.

(Comparative Examples 1 and 2) The components shown in Table 1 were blended, and the same evaluation as in Examples 1 to 5 was performed. Table 1 shows the results.

[0048]

[Table 1]

The coating film using the photosensitive resin composition of the present invention showed excellent physical properties in adhesion, solder resistance and PCT resistance, and a remarkable improvement in PCT resistance was particularly observed.

[0050]

The photosensitive resin composition of the present invention is capable of forming an image by developing with a dilute alkaline aqueous solution in pattern formation by exposing to ultraviolet light through a patterned positive film and developing the exposed portion. The cured film is cured by a short heat treatment after the pattern is formed, and the cured film is suitable for a solder resist or an interlayer insulating material excellent in various properties such as adhesion, solder resistance, pressure cooker resistance, and low water absorption.

Continued on the front page (72) Inventor Yoshifumi Asai Oita City, Oita Prefecture, Oita City, No. 2, Oita Plant Showa Denko Corporation Oita Plant (72) Inventor Hirotaka Tagoshi 1-1-1, Onodai, Midori-ku, Chiba City, Chiba Prefecture F-term in Showa Denko KK, R & D center (reference)

Claims (12)

[Claims] 1. A compound (A) having an oxetane structure,
A photosensitive resin composition comprising a compound having a radically polymerizable unsaturated group (B), a photoradical initiator (C), and a cationic polymerization initiator (D). 2. The photosensitive resin composition according to claim 1, further comprising an alkali-soluble resin (E). 3. The photosensitive resin composition according to claim 1, comprising a compound (F) having an epoxy group. 4. The compound (A) having at least one alicyclic structure other than an oxetane ring, as the compound (A) having an oxetane structure, used alone or in combination of two or more. The photosensitive resin composition according to any one of the above. 5. The compound (A) having an oxetane structure is represented by the formula (1): [Wherein, m is an integer of 0 to 2, and n is 2, when m is 0,
Otherwise, it is 1 and X represents a hydrogen atom or a methyl group. The photosensitive resin composition according to any one of claims 1 to 4, which is a compound represented by the formula: 6. The compound (A) having an oxetane structure includes 2-oxaspiro [3.5] nonane, 7-methyl-2-oxaspiro [3.5] nonane, and spiro [bicyclo [2.2.1] heptane. -2,3'-oxetane],
5-methyl-2-oxaspiro [3.5] nonane, spiro [3-methylbicyclo [2.2.1] heptane-2,
3'-oxetane] or 2 selected from the group consisting of
The photosensitive resin composition according to any one of claims 1 to 5, wherein at least one kind is used. 7. The compound (A) having an oxetane structure is used in an amount of 1 to 100 parts by weight of the alkali-soluble resin (E).
The photosensitive resin composition according to any one of claims 1 to 6, which is used in an amount of 50 parts by weight. 8. The photosensitive resin composition according to claim 1, which is used as a resist material. 9. A cured film obtained by curing the photosensitive resin composition according to claim 1. 10. A cured solder resist film comprising the cured film according to claim 9. 11. An interlayer insulating cured film for a multilayer wiring board comprising the cured film according to claim 9. 12. In the formation of a cured film, the photosensitive resin composition according to any one of claims 1 to 8 is used to cure a radical polymerizable compound upon irradiation with light and a part of a compound capable of cationic polymerization. Alternatively, a method for producing a cured film, wherein the entirety is cationically cured.