JPH07319154A - Novel photopolymerizable resin composition - Google Patents

Abstract

PURPOSE:To obtain this photopolymerizable resin compsn. suitable for a dry film photoresist, having superior performance. CONSTITUTION:This photopolymerizable resin compsn. contains 20-90wt.% polymer having a carboxyl group content of 100-600 (expressed in terms of acid equiv.) and a wt. average mol.wt. of 20,000-500,000, 5-60wt.% photopolymerizable monomer having at least two terminal ethylene groups, 0.01-20wt.% photopolymn. initiator and 1-20wt.% compd. represented by the formula (where R1 its H or acetyl and R2 is 1-8C alkyl) as essential components.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alkali-developable photopolymerizable resin composition suitable for producing a printed wiring board.

[0002]

2. Description of the Related Art Conventionally, a so-called dry film photoresist (hereinafter abbreviated as DFR) comprising a support layer and a photopolymerizable layer has been used as a resist for producing a printed wiring board. The DFR is generally prepared by laminating a photopolymerizable layer composed of a photopolymerizable composition on a support layer, and in many cases further laminating a protective film on the composition. As the photopolymerizable layer, an alkali developing type using a weak alkaline aqueous solution as a developing solution is generally used.

To make a printed wiring board using DFR, first peel off the protective film and then use a laminator or the like on a permanent circuit forming substrate such as a copper clad laminate.
Are stacked. Next, the support layer is peeled off if necessary, and exposure is performed through a wiring pattern mask film or the like. If there is a support layer after exposure, the support layer is peeled off if necessary, and the unexposed portion of the photopolymerizable layer is dissolved or dispersed and removed to form a cured resist image on the substrate. Using the formed resist image as a mask, the metal surface of the substrate is subjected to etching or plating, and then the resist image is peeled off using an alkaline aqueous solution stronger than the developing solution to form a printed wiring board or the like. In particular, recently, a so-called tenting method of covering a through-hole (through-hole) with a cured film and then etching is widely used because of the simplicity of the process.

For etching, cupric chloride, ferric chloride, copper ammonia complex solution, etc. are used. When the cured film is broken by the pressure of spray or the like in the steps of development and etching, the conductor inside is removed. , Disconnection and lead to defects. Therefore, a strong film strength that does not break and flexibility are required. On the other hand, since the DFR is stored in a roll state having a three-layer structure, a phenomenon called so-called cold flow that the photopolymerizable layer protrudes from the end surface during storage may occur.
Not preferable for handling. Furthermore, if the unexposed photopolymerizable layer is hard, when the DFR is laminated on the substrate and then cut with a cutter or the like, a so-called cut chip occurs, which causes the photopolymerizable layer to be broken into chips, which is generated. If it adheres to the surface of the substrate, it will lead to defects during exposure and cause serious problems. In addition, if the unexposed photopolymerizable layer is hard, the adhesion is poor when it is laminated on the substrate, and on the uneven substrate surface, the photopolymerizable layer cannot fill the irregularities and creates spaces. There is. If this occurs when used as an etching resist, the etching solution penetrates, leading to defects such as disconnection and chipping.

The photopolymerizable layer of DFR, which is widely used at present, has (1) an unsaturated compound having at least one ethylenic group and capable of forming a polymer by a photopolymerization initiator,
It is composed of a composition comprising (2) a thermoplastic organic polymer binder, (3) a photopolymerization initiator, and (4) other additives. (Japanese Patent Publication No. 50-9177 and Japanese Patent Publication No. 57-21697). As the unsaturated compound, acrylic acid and methacrylic acid esters of aliphatic polyhydric alcohols are the most common, and at least two unsaturated groups such as trimethylolpropane triacrylate pentaerythritol triacrylate and polyethylene glycol diacrylate are used. It is known to have.

[0006]

In order to improve the cold flow, it is necessary to relatively increase the compounding ratio of the binder, but if this is done, cut chips will occur and the ability to follow the substrate will deteriorate. To do. Also, the flexibility and strength of the tenting film are reduced. In order to prevent the generation of cut chips, the blending ratio of the binder may be relatively decreased, but this causes problems such as cold flow, deterioration of developability, and increase of peeling time.

Conventionally, in order to improve these problems, a plasticizer such as toluenesulfonamide has been used.
Conventionally known plasticizers have not been able to solve the above problems.

[0008]

Means for Solving the Problems As a result of repeated studies to solve the above problems, a photopolymerizable composition containing a compound of the following general formula (I) gives a cured resist when used in DFR. Good flexibility, strong tent film strength, good cold flow and substrate followability, can be stored at room temperature for 6 months or more, and chips do not occur when cutting DFR when not exposed. They have found that they have characteristics, and completed the present invention.

That is, in the present invention, the carboxyl group content is 100 to 600 in acid equivalent and the weight average molecular weight is 20,000 to.
500,000 to 20% by weight of polymer, 5 to 60% by weight of a photopolymerizable monomer having at least two terminal ethylene groups, 0.01 to 20% by weight of a photopolymerization initiator, and the following general formula (I). The present invention relates to a photopolymerizable resin composition containing 1 to 20% by weight of the compound.

[0010]

[Chemical 4]

(Where R ₁ is hydrogen or an acetyl group, R 1
₂ represents an alkyl group having 1 to 8 carbon atoms) In the general formula (I), R ₁ is hydrogen or an acetyl group,
R ₂ is an alkyl group having 1 to 8 carbon atoms, and particularly preferable is an alkyl group having 2 to 6 carbon atoms. Specific examples include tributyl citrate, triethyl citrate, triethyl acetyl citrate, tri-n-propyl acetyl citrate, tri-n-butyl acetyl citrate, and the like.

Examples of the photopolymerizable monomer having at least two terminal ethylene groups constituting the above photopolymerizable resin composition include 1,6-hexanediol di (meth) acrylate and 1,4-cyclohexanediol di ( Meta)
Acrylate, polypropylene glycol di (meth) acrylate, polyethylene glycol di (meth)
Acrylate, polyoxyalkylene glycol di (meth) acrylate such as polyoxyethylene polyoxypropylene glycol di (meth) acrylate, 2-di (p-hydroxyphenyl) propane di (meth) acrylate, glycerol tri (meth) acrylate, trimethylol Propane tri (meth) acrylate, polyoxypropyl trimethylolpropane tri (meth) acrylate, polyoxyethyl trimethylolpropane triacrylate, dipentaerythritol penta (meth) acrylate, trimethylolpropane triglycidyl ether tri (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate,
There are 2,2-bis (4-methacryloxypentaethoxyphenyl) propane, polyfunctional (meth) acrylates containing a urethane group, and the like. As a preferable example,
Examples include those represented by the general formulas (II) and (III). These may be used alone or in combination with other polyfunctional or monofunctional monomers. A system in which the monomers of the general formulas (II) and (III) are used in combination is also desirable, and by using these monomers, a tenting film having good followability, flexibility and toughness can be obtained.

[0013]

[Chemical 5]

(Wherein R ₃ is a diisocyanate residue having 4 to 12 carbon atoms, R ₄ and R ₅ are hydrogen or a methyl group,
n ₁ and n ₂ represent an integer of 1 to 15)

[0015]

[Chemical 6]

(Wherein n ₃ , n ₄ and n ₅ are integers of 3 to 20 and R ₆ and R ₇ are hydrogen or a methyl group) Examples of the compound represented by (II) include hexamethylene diisocyanate, A diisocyanate compound such as tolylene diisocyanate or 2,2,4-trimethylhexamethylene diisocyanate, and a compound having a hydroxyl group and a (meth) acryl group in one molecule (for example, 2-hydroxypropyl acrylate, oligopropylene glycol monomethacrylate, etc.) ) And urethane compound. These can be synthesized by a known method.

In the compound represented by the general formula (III), when n ₃ , n ₄ and n ₅ are smaller than 3, the boiling point of the compound is lowered, the odor of the resist becomes strong, and the use becomes extremely difficult. Become. On the other hand, when n ₃ , n ₄ , and n ₅ exceed 20, the concentration of photoactive sites per unit weight becomes low, and practical sensitivity cannot be obtained. The compound represented by the general formula (III) is commercially available, and the product obtained by reacting propylene oxide and ethylene oxide is esterified with acrylic acid or methacrylic acid in the presence of a suitable acid catalyst. It can also be synthesized.

These monomers may be used alone or in combination of two or more. The amount used is selected from the range of 5 to 60% by weight. When it is less than 5% by weight, the sensitivity and film strength are not sufficient, and when it exceeds 60% by weight, the photopolymerizable layer during storage when used for DFR. This is not preferable, because the protrusion of the notch becomes remarkable. The amount of the carboxyl group contained in the polymer used in the present invention needs to be 100 to 600 in terms of acid equivalent, and preferably 300 to 400. The molecular weight is 20,000-5.
It is necessary to be 0,000, and more preferably 40,000 to 200,000. Here, the acid equivalent means the weight of a polymer having 1 equivalent of a carboxyl group therein. The carboxyl group in the polymer is necessary for giving the DFR developability and releasability to an aqueous alkaline solution. When the acid equivalent is less than 100, the compatibility with the coating solvent or other composition such as a monomer is lowered, and when it exceeds 600, the developability and the peelability are lowered. Further, when the molecular weight exceeds 500,000, the developability decreases, and when it is less than 20,000, it becomes difficult to keep the thickness of the photopolymerizable layer uniform when used in the photopolymerizable laminate, and the resistance to the developing solution becomes low. Getting worse. The acid equivalent was measured using a Hiranuma reporting titrator COMTITE-7,
Performed by potentiometric titration with 0.1 N sodium hydroxide. Further, the molecular weight is determined as a weight average molecular weight by gel permeation chromatography manufactured by JASCO (pump: TRIROTAR-V, column: Shodex A-80M 2 series, mobile phase solvent: THF, using a calibration curve based on a polystyrene standard sample). .

The polymer can be obtained by copolymerizing one or more of the following two types of monomers. The first monomer is a carboxylic acid or acid anhydride having one polymerizable unsaturated group in the molecule. For example, (meth) acrylic acid, fumaric acid, cinnamic acid, crotonic acid, itaconic acid, maleic anhydride, maleic acid half ester and the like. The second monomer is non-acidic, has one polymerizable unsaturated group in the molecule, and has various properties such as developability of the photopolymerizable layer, resistance in etching and plating steps, and flexibility of the cured film. Selected to retain properties. For example, methyl (meth) acrylate, ethyl (meth) acrylate,
There are alkyl (meth) acrylates such as butyl (meth) acrylate and 2-ethylhexyl (meth) acrylate. In addition, there are vinyl alcohol esters such as vinyl acetate, styrene, or a polymerizable styrene derivative. It can also be obtained by polymerizing only the above-mentioned carboxylic acid or acid anhydride having one polymerizable unsaturated group in the molecule.

The amount of the polymer contained in the photopolymerizable composition is in the range of 20 to 90% by weight, preferably 30 to 90% by weight.
It is 70% by weight. When the amount of the polymer is less than 20% by weight or more than 90% by weight, the cured image formed by exposure does not have sufficient resist properties, for example, sufficient resistance in tenting, etching and various plating steps.

Examples of the photopolymerization initiator that can be used in the present invention include known initiators that are activated by various actinic rays such as ultraviolet rays to initiate polymerization.
For example, 2-ethylanthraquinone, octaethylanthraquinone, 1,2-benzanthraquinone, 2,3
-Benzanthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl- 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,
4-naphthoquinone, 2,3-dimethylanthraquinone,
Quinones such as 3-chloro-2-methylanthraquinone, benzophenone, Michler's ketone [4,4′-bis (dimethylamino) benzophenone], aromatic ketones such as 4,4′-bis (diethylamino) benzophenone, benzoin, benzoin Benzoin ethers such as ethyl ether, benzoin phenyl ether, methylbenzoin and ethylbenzoin, benzyldimethyl ketal, benzyl diethyl ketal, biimidazole compounds such as 2- (o-chlorophenyl-4,5-diphenylimidazolyl dimer), thioxanthones And a combination of alkylaminobenzoic acid, such as ethylthioxanthone and ethyl dimethylaminobenzoate, 2-chlorothioxanthone and ethyl dimethylaminobenzoate, and isopropylthioxanthone. The combination of methyl amino benzoate, also 2-(o-chlorophenyl) -4,
A combination of 5-diphenyl imidazolyl dimer and Michler's ketone, and further 2- (o-chlorophenyl)-
Combination of 4,5-diphenyl imidazolyl dimer, benzyl dimethyl ketal and Michler's ketone, 9-
Acridines such as phenylacridine, 1-phenyl-
1,2-propanedione-2-o-benzoyloxime, 1-phenyl-1,2-propanedione-2- (o
There are oxime esters such as -ethoxycarbonyl) oxime. These initiators may be used alone or in combination. Preferred examples of the initiator include thioxanthones such as diethylthioxanthone and chlorothioxanthone, dialkylaminobenzoic acid esters such as ethyl dimethylaminobenzoate, benzophenone, 4,4′-bis (dimethylamino) benzophenone and 4,4 ′. -Bis (diethylamino) benzophenone, 2- (o-chlorophenyl) -4,5-diphenylimidazolyl dimer, and combinations thereof.

The amount of the photopolymerization initiator contained in the photopolymerizable composition of the present invention is 0.01% by weight to 20% by weight,
It is preferably 0.05% by weight to 10% by weight. When the amount of the photopolymerization initiator exceeds 20% by weight, the active absorption rate of the photopolymerizable composition becomes high, and when used as a photopolymerization laminate, curing due to polymerization of the bottom portion of the photopolymerization layer becomes insufficient. If it is less than 0.01% by weight, sufficient sensitivity cannot be obtained.

In order to improve the thermal stability and storage stability of the photopolymerizable composition of the present invention, it is preferable to add a polymerization inhibitor to the photopolymerizable composition. For example, p
-Methoxyphenol, hydroquinone, pyrogallol, naphthylamine, tert-butylcatechol, cuprous chloride, 2,6-di-tert-butyl-p-cresol, 2,2'-methylenebis (4-ethyl-6-te)
rt-butylphenol), 2,2′-methylenebis (4-methyl-6-tert-butylphenol), nitrosophenylhydroxyamine aluminum salt, diphenylnitrosamine, etc. The photopolymerizable composition of the present invention includes a dye, a pigment and the like. You may contain the coloring substance of.
For example, fuchsin, phthalocyanine green, auramine base, chalcoxide green S, paramagenta, crystal violet, methyl orange, Nile blue 2
B, Victoria blue, malachite green, basic blue 20, diamond green and the like.

Further, a color-forming dye that develops color upon irradiation with light may be contained. As the color forming dye, there is a combination of a leuco dye or a fluoran dye and a halogen compound. For example, tris (4-dimethylamino-2-methylphenyl) methane [leuco crystal violet],
Examples include tris (4-dimethylamino-2-methylphenyl) methane [leucoma rachaichi green] and the like. On the other hand, as the halogen compound, amyl bromide, isoamyl bromide, isobutylene bromide, ethylene bromide, diphenylmethyl bromide, benzal bromide, methylene bromide, tribromomethylphenyl sulfone, carbon tetrabromide, tris (2 , 3
-Dibromopropyl) phosphate, trichloroacetamide, amyl iodide, isobutyl iodide, 1,1,1
-Trichloro-2,2-bis (p-chlorophenyl) ethane, hexachloroethane, triazine compounds and the like.

As the triazine compound, 2,4,6-
Tris (trichloromethyl) -s-triazine, 2-
(4-Methoxyphenyl) -4,6-bis (trichloromethyl) -s-triazine may be mentioned. Further, a combination of tribromomethylphenyl sulfone and a leuco dye and a combination of a triazine compound and a leuco dye are useful.

Further, a small amount of a glycidyl ether compound may be added to the photopolymerizable resin composition of the present invention as a thermal color-developing agent. Specific examples include polypropylene glycol diglycidyl ether, glycerin diglycidyl ether, hydrogenated bisphenol A diglycidyl ether,
Bisphenol A-PO2 mol addition diglycidyl ether etc. are mentioned.

In the case of a photopolymerizable resin laminate for DFR, a support layer supporting the photopolymerizable layer is laminated on the photopolymerizable layer containing the photopolymerizable resin composition. As the support layer, a transparent layer that transmits active light is desirable. As the support layer that transmits active light, a polyethylene terephthalate film, a polyvinyl alcohol film, a polyvinyl chloride film, a vinyl chloride copolymer film, a polyvinylidene chloride film, a vinylidene chloride copolymer film, a polymethyl methacrylate copolymer film, Examples thereof include polystyrene film, polyacrylonitrile film, styrene copolymer film, polyamide film, and cellulose derivative film. These films may be stretched if necessary. The thinner the thickness, the more advantageous in terms of the image forming property and the economical efficiency, but the thickness is generally 10 to 30 μm in order to maintain the strength.

If necessary, a protective layer is laminated on the surface opposite to the photopolymerizable layer laminated with the support layer. An important characteristic of this protective layer is that the protective layer is sufficiently smaller than the support layer in terms of adhesion to the photopolymerizable layer and can be easily peeled off. For example, there are polyethylene film, polypropylene film and the like. Further, the film having excellent releasability disclosed in JP-A-59-202457 can be used. Although the thickness of the photopolymerizable layer varies depending on the use, it is 5 to 100 μm, preferably 5 to 90 μm for producing a printed circuit board.
m, and the thinner, the higher the resolution. Further, the thicker the film, the higher the film strength.

Next, a process for producing a printed circuit board using this photopolymerizable resin laminate is in accordance with the prior art, but will be briefly described. First, using a laminator, if there is a protective layer, the protective layer is peeled off, and then the photopolymerizable layer is laminated on the metal surface of the printed circuit board substrate by thermocompression bonding. The heating temperature at this time is generally 40 to 160 ° C. Then, if necessary, the support layer is peeled off and imagewise exposed to actinic light through a mask film. Next, if there is a support layer on the post-exposure photopolymerizable layer, the support layer is removed if necessary, and subsequently, the unexposed portion is developed and removed using a developer of an alkaline aqueous solution. As the alkaline aqueous solution, an aqueous solution of sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide or the like is used.

These are selected according to the characteristics of the photopolymerizable layer, but an aqueous 0.5% to 3% sodium carbonate solution is generally used. Next, a metal image pattern is formed on the metal surface exposed by the development using a known method such as an etching method or a plating method. The cured resist image is then stripped with an alkaline aqueous solution that is generally stronger than the alkaline aqueous solution used for development. The alkaline aqueous solution for stripping is also not particularly limited, but an aqueous solution of 1% to 5% sodium hydroxide or potassium hydroxide is generally used. Furthermore, it is possible to add a small amount of a water-soluble solvent to the developing solution or the stripping solution.

[0031]

EXAMPLES Examples will be shown below.

[0032]

Example 1 The compounds described in the column of Example 1 in Table 1 were uniformly dissolved. Next, this mixed solution was uniformly applied to a polyethylene terephthalate film having a thickness of 25 μm using a bar coater and dried in a dryer at 90 ° C. for 5 minutes to laminate a photopolymerizable resin layer having a thickness of 50 μm. Got the body Then, a 35 μm polyethylene film was laminated on the surface of the photopolymerizable layer on which the polyethylene terephthalate film was not laminated to obtain a laminated film. On the other hand, 35μ
Wet baffle made of copper-clad laminate with m rolled copper foil laminated (3M, Scotch Bright # 6002 series)
A photopolymerizable layer was laminated on a polished surface of the laminated film at 105 ° C. by a hot roll laminator while peeling off the polyethylene film of the laminated film to obtain a laminate.

An ultra-high pressure mercury lamp (HMW-201KB, manufactured by Oak Manufacturing Co., Ltd.) is passed through this laminate through a mask film.
Was used to expose the photopolymerizable layer at 80 mJ / cm ² . Then, after peeling off the polyethylene terephthalate film,
A 1% aqueous sodium carbonate solution at 30 ° C. was sprayed for about 70 seconds to dissolve and remove the unexposed portion, and a good cured image was obtained. The following method evaluated. (1) Cold Flow Test The above laminate was cut into 2.5 cm square pieces, sandwiched between iron plates having a diameter of 10 cm, and a load of 100 kg was applied at 40 ° C. for 5 minutes. The sample was taken out, and the width of protrusion of the photopolymerizable layer was measured. The following rankings were used for evaluation.

○: less than 300 μm, 23 in roll state
Can be stored at ℃ for 6 months or more without cold flow. Δ: 300 μm or more and less than 600 μm, can be stored under the same conditions for 1 month or more and less than 6 months without cold flow. ×: 600 μm or more and less than 1 month Can be stored without cold flow. (2) Evaluation of Cut Chips A laminate was laminated on a copper-clad laminate by the method described in the example, the laminate was cut along the laminate with a cutter knife, and the cut surface was observed and evaluated by the following method. .

○: Can be cut without the chip flying. X: Chip fly occurs during cutting. (3) Follow-up evaluation test Laminate-exposure-development-etching-resist stripping was performed on a copper-clad laminate in which 70 μm rolled copper foil was laminated using a commercially available dry film resist in advance to obtain a line width of 100, 110, 120, 130, 140, 15
A 0 μm linear groove was formed. The depth of the groove was about 10 μm.

Using the grooved substrate thus prepared, the above laminate was laminated in the same manner as above. An image pattern was obtained by exposing and developing a line pattern (line width; 125 μm) that was perpendicular to the groove of the substrate through the laminate with a mask film. Furthermore, 5
A cupric chloride solution at 0 ° C. was sprayed for 120 seconds to etch the copper in the resist-free area. Finally 3% of 50 ℃
An aqueous solution of sodium hydroxide was sprayed for about 90 seconds to remove the cured resist.

On the copper line thus produced, the number of points where the grooved portions were not broken was counted as x. On the other hand, count the number of points that are broken due to etching.
The disconnection rate (%) was calculated by the following formula, and ranked by the following method. Breakage rate (%) = 100x / (x + y) ○; Breaking rate is less than 10% △; Breaking rate is 10% or more and less than 40% ×; Breaking rate is 40% or more (4) Flexibility and membrane strength evaluation of 5 mm diameter A copper clad laminate having through holes was laminated on both sides by the method described in Example 1, exposed and developed without using a pattern mask to remove the cured film on one side, and a tensile tester was used. The piercing bar was set in the jig and the center of the through-hole film was pressed at a speed of 10 mm / min with a load of 5 kg. As a result, the elongation of the cured film until the film was broken and the strength at that time were measured.

[0038]

Examples 2 to 8 and Comparative Examples 1 to 4 By the same method as in Example 1, photopolymerizable resin laminates having the compositions shown in Table 1 and Table 2 were obtained, and flowability test, cut chip test, followability Tests, flexibility and film strength tests were conducted. The results are shown in Tables 1 and 2. <Symbols> P: Methyl ethyl ketone solution of terpolymer of 57% by weight of methyl methacrylate, 23% by weight of methacrylic acid, and 10% by weight of butyl acrylate (solid content concentration 32%, weight average molecular weight 85,000) M-1: trimethylolpropane triacrylate M-2: hexamethylene diisocyanate and oligopropylene glycol monomethacrylate (NOF Corporation)
Reaction product with Blemmer PP-1000) M-3: Dimethacrylate of glycol obtained by adding 3 mol of ethylene oxide to both ends of polypropylene glycol on average of 8 mol of propylene oxide on average, M-4: tetrapropylene glycol dimethacrylate. A-1: Diethylthioxanthone A-2: Ethyl p- (N, N-dimethylamino) benzoate A-3: 4,4′-Bis (diethylamino) benzophenone A-4: 2- (o-chlorophenyl) -4 , 5-Diphenylimidazolyl dimer B-1: Malachite Green B-2: Leuco Crystal Violet B-3: Tribromomethylphenylsulfone C-1: Tributyl Citrate C-2: Acetyl Tributyl Citrate C-3: Polyethylene Glycol C-4: Li Acid tributyl

[0039]

[Table 1]

[0040]

[Table 2]

[0041]

EFFECT OF THE INVENTION The dry film photoresist using the photopolymerizable resin composition of the present invention has a low cold flow property particularly during storage, and has a cut chip property of an unexposed film during lamination on a substrate. , And excellent followability, and further shows excellent flexibility and film strength of a cured film after exposure, and is very useful as a dry film resist for producing an alkali development type circuit board.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical indication H05K 3/00 F 3/06 H 3/18 D 7511-4E

Claims (2)

[Claims] 1. The carboxyl group content is 10 in terms of acid equivalent.
Polymer 2 having a weight average molecular weight of 0 to 600 and 20,000 to 500,000
0 to 90% by weight, 5 to 60% by weight of a photopolymerizable monomer having at least two terminal ethylene groups, 0.01 to 20% by weight of a photopolymerization initiator, and compounds 1 to 20 represented by the following general formula (I). A photopolymerizable resin composition, characterized in that the photopolymerizable resin composition is contained in an amount of 1% by weight. [Chemical 1] (Here, R ₁ is hydrogen or acetyl group, R ₂ is carbon number 1
~ Represents an alkyl group of 8) 2. A photopolymerizable monomer having at least two terminal ethylene groups is represented by the following general formula (II) or (II
The photopolymerizable resin composition according to claim 1, which is a compound containing I). [Chemical 2] (Here, R ₃ is a diisocyanate residue having 4 to 12 carbon atoms, R ₄ and R ₅ are hydrogen or a methyl group, and n ₁ and n ₂ are 1
Represents an integer of -15. ) [Chemical 3] (Here, n ₃ , n ₄ and n ₅ are integers of 3 to 20, R ₆ and R
₇ represents hydrogen or a methyl group)