JPH0895241A - Photosensitive resin composition and photosensitive element using same - Google Patents

Abstract

PURPOSE: To provide a photosensitive resin compsn. excellent in followup ability and adhesion even to a substrate having high surface roughness and not causing exudation from the edge faces of a roll even when a photosensitive element using the resin compsn. is fed in a roll shape and to provide a photosensitive element using the resin compsn. CONSTITUTION: This photosensitive resin compsn. contains 100 pts.wt., in total, of 40-80 pts.wt. film property imparting polymer made of a vinyl copolymer having carboxyl groups and 20-60 pts.wt. crosslinking agent having an ethylenically unsatd. bond and 0.01-20 pts.wt. photopolymn. reaction initiator which generates free radicals under active rays. This resin compsn. has 20-100 MPa.sec viscosity at 30 deg.C and 10-70kPa.sec viscosity at 80 deg.C.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photosensitive resin composition, more specifically, as an etching resist or a plating resist used in the production of printed wiring boards, precision processing of metals, etc. The present invention relates to a photosensitive resin composition and a photosensitive element using the same.

[0002]

2. Description of the Related Art In the fields of manufacturing printed wiring boards, precision processing of metals, etc., chemicals of base materials such as etching and plating,
It is known to use a photosensitive resin composition and a photosensitive element using the same as a resist material when an electrical method is used. As the photosensitive element, one in which a photosensitive resin composition is laminated on a support is widely used. Conventionally, there are two methods of manufacturing a printed wiring board, a tenting method and a plating method. In the tenting method, a through hole for mounting a chip is protected with a resist, and an electric circuit is formed through etching and resist peeling, whereas the plating method deposits copper in the through hole by electroplating or the like. And protect with solder plating,
This is a method of forming an electric circuit by removing the resist and etching. Usually, the photosensitive element is heated by a heating roll to be laminated on the copper clad laminate, and is exposed and developed to form a resist circuit on the copper surface. In this case, if the adhesiveness or followability of the photosensitive resin composition to the copper surface is not sufficient, chipping or disconnection of the electric circuit occurs during etching in the tenting method, and in the plating method, it may occur in areas where adhesion is poor. Penetration of the plating solution occurs, which induces chipping of the plating or short circuit of the electric circuit.

On the other hand, the surface roughness of the conventional copper clad laminate is 3 to.
Although it was 5 μm, in recent years, a substrate having a surface roughness of 7.5 to 12 μm is commercially available in order to reduce the manufacturing cost of the copper clad laminate. In particular, when laminating a conventional photosensitive element on a substrate having a large surface roughness, the adhesion of the photosensitive resin composition to the substrate, the followability is further deteriorated, chipping, disconnection,
Short circuit defects increase and the production yield of printed wiring boards is significantly reduced. As one of means for solving this problem, a method of softening the photosensitive resin composition to increase fluidity can be considered. However, when tension is applied to the photosensitive element and the photosensitive element is supplied in the form of a roll, if the photosensitive resin composition is soft, the photosensitive resin composition exudes to the outside from the end surface of the roll, and when the photosensitive element is laminated, the photosensitive element is steadily formed. Not only is it difficult to feed out, but the exuded portion is transferred onto the substrate and left undeveloped, which significantly reduces the production yield of the printed wiring board.

[0004]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, has excellent followability and adhesion even to a substrate having a large surface roughness, and provides a photosensitive element. Provided is a photosensitive resin composition in which the photosensitive resin composition does not exude from the end face of the roll even when supplied in a roll form, and a photosensitive element using the same.

[0005]

The present invention comprises 40 to 80 parts by weight of a film-forming polymer composed of a carboxyl group-containing vinyl copolymer, 20 to 60 parts by weight of a cross-linking agent having an ethylenically unsaturated bond, and actinic radiation. A photopolymerization initiator composition containing 0.01 to 20 parts by weight of a photopolymerization initiator that produces free radicals (used in such an amount that the total amount of the film-forming polymer and the crosslinking agent is 100 parts by weight). Viscosity at ℃ is 20-100MPasec, viscosity at 80 ℃ is 10
The present invention relates to a photosensitive resin composition having a viscosity of ˜70 kPa · sec and a photosensitive element formed by laminating a layer of the photosensitive resin composition on a support.

The present invention will be described in detail below. The viscosity of the photosensitive resin composition at 30 ° C. is required to be 20 MPa · sec or more in order to prevent the photosensitive resin composition from seeping out from the end surface of the photosensitive element wound in a roll for 1 month or more. Yes, and preferably 25 MPa · sec or more. The viscosity of the photosensitive resin composition at 30 ° C. is 1
It is necessary to be less than 00MPa ・ sec, 80MPa ・ sec
Is preferred. When the viscosity exceeds 100 MPa · sec, fragments of the photosensitive resin composition are generated when the photosensitive element is cut, and the fragments adhere to the laminated substrate to cause defective exposure or undeveloped residue.

The viscosity of the photosensitive resin composition at 80 ° C. is required to be 70 kPa · sec or less from the viewpoint that when the photosensitive element is heated with a heating roll and laminated on the substrate, the unevenness of 12 μm of the substrate is followed. Yes, 50kPa
-It is preferably sec or less. Further, the viscosity of the photosensitive resin composition at 80 ° C. needs to be 10 kPa · sec or more, and preferably 15 kPa · sec or more. The viscosity of the photosensitive resin composition at 80 ° C is 10 kPa
When it is less than sec, when the photosensitive element is heated by a heating roll and laminated on a copper clad laminate or the like, the photosensitive resin composition contaminates the heating roll and causes lamination failure. As described above, the viscosity of the photosensitive resin composition is 20 to 10 at 30 ° C.
0 MPa · sec, preferably 25 to 80 MPa · sec, and 10 to 70 kPa · sec at 80 ° C., preferably 1
It is 5 to 50 kPa · sec. The above viscosity is 7m in diameter.
3 in the thickness direction of the photosensitive resin composition sample having a thickness of m and a thickness of 2 mm
A pressure of 20 g weight at 0 ° C. and a pressure of 2 g weight at 80 ° C. are applied to measure the rate of change in thickness, and the value is a value converted into viscosity assuming a Newtonian fluid from this rate of change.

The photosensitive resin composition according to the present invention comprises a film-forming polymer (hereinafter simply referred to as a film-forming polymer) 40 composed of a carboxyl group-containing vinyl copolymer.
˜80 parts by weight, the cross-linking agent having an ethylenically unsaturated bond (hereinafter, simply referred to as a cross-linking agent) is in the range of 20 to 60 parts by weight, and the total amount of the film-forming polymer and the cross-linking agent is 100 parts by weight. To use. If the content is outside this range, the viscosity of the photosensitive resin composition is 20 to 100 MPa · sec at 30 ° C., 80
It becomes difficult to set the temperature in the range of 10 to 70 kPa · sec at a temperature of ℃. A conventional photosensitive resin composition has a viscosity of 30 ° C. and a viscosity of 80
The difference between the viscosity at 30 ° C and the viscosity at 30 ° C is not enough.
Adjust the viscosity at 80 ℃ to 10 MPa within the range of 100 MPa ・ sec.
It was difficult to set the range of up to 70 kPa · sec. On the other hand, according to the present invention, for example, as a crosslinking agent,
By using one or both of a crosslinking agent having a melting point at 80 ° C. and a crystalline polymer having a crystallization temperature at 30 to 80 ° C. as a film property imparting polymer, 30% of the photosensitive resin composition can be obtained.
The difference in viscosity between ℃ and 80 ℃ can be increased to 30 ℃
Viscosity at 20MPa ・ sec or more and 100MPa ・ sec or less,
And the viscosity at 80 ℃ is 70kPa ・ sec or less, 10kPa ・ sec
The above can be done. In the present invention, the melting point of the cross-linking agent having a wide range of molecular weight and the crystallization temperature of the crystalline polymer refer to the temperature at which the change in viscosity becomes the largest.

The crosslinking agent in the present invention is not particularly limited, but it is preferable to use a methacrylate monomer or an acrylate monomer from the viewpoint of high sensitivity. From the viewpoint of adjusting the viscosity of the photosensitive resin composition, it is preferable to use a cross-linking agent having a melting point of 30 to 80 ° C. Examples thereof include tris (acryloxyethyl) isocyanurate,
Tris (methacryloxyethyl) isocyanurate, methoxypolyethylene glycol 1000 methacrylate, polyethylene glycol 1000 dimethacrylate, polystyrylethyl methacrylate, 4- (2,
2,6,6-Tetramethylpiperidinyl) methacrylate, bisphenol A dimethacrylate, bisphenol epoxy acrylate, urethane acrylate and the like are mentioned, and among them, tris (acryloxyethyl) isocyanurate, methoxypolyethylene glycol 1000.
Methacrylate, polyethylene glycol 1000 dimethacrylate, 4- (2,2,6,6-tetramethylpiperidinyl) methacrylate, bisphenol epoxy acrylate, urethane acrylate monomer (molecular weight of 1,000 or more) is preferable, and tris ( Acryloxyethyl) isocyanurate, polyethylene glycol 1
000 dimethacrylate and 4- (2,2,6,6-tetramethylpiperidinyl) methacrylate are more preferred. The use of these cross-linking agents is particularly effective when the film-forming polymer does not have a crystallization temperature of 30 to 80 ° C., and may be used alone or in combination of two or more. Three
When a crosslinking agent having a melting point of 0 to 80 ° C. is used, it is preferably used in an amount of 1 to 90% by weight, more preferably 2 to 75% by weight, based on the total amount of the crosslinking agent. If it exceeds 90% by weight, 3 of the photosensitive resin composition
Viscosity at 0 ° C tends to be too high, 1% by weight
If it is less than the above, the effect of sufficiently increasing the viscosity difference between 30 ° C. and 80 ° C. tends to be small.

The melting point of the crosslinking agent in the present invention is 30 ° C.
Less than a cross-linking agent may be used, and as such a compound, any of those conventionally known as photopolymerizable monomers can be used. Such cross-linking agents include polyethylene glycol di (meth) acrylate (having 2 to 14 ethylene groups), trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane ethoxy. Tri (meth) acrylate, trimethylolpropane propoxytri (meth) acrylate, tetramethylolmethane tri (meth) acrylate, tetramethylolmethane tetra (meth) acrylate, polypropylene glycol di (meth) acrylate (the number of propylene groups is 2 to 14). ), Dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, bisphenol A polyoxyethylene di (meth) acrylate, bisphenol A Compounds obtained by adding α, β-unsaturated carboxylic acid to oxyethylene di (meth) acrylate, bisphenol A trioxyethylene di (meth) acrylate, bisphenol A decaoxyethylene di (meth) acrylate, glycidyl group-containing compound , For example, trimethylolpropane triglycidyl ether tri (meth) acrylate,
Bisphenol A diglycidyl ether diacrylate, polyvalent carboxylic acid, for example, an esterification product of a substance having a hydroxyl group and an ethylenically unsaturated group with phthalic anhydride and the like, for example, β-hydroxyethyl (meth) acrylate, acrylic acid or Alkyl ester of methacrylic acid,
For example, (meth) acrylic acid methyl ester, (meth)
Acrylic acid ethyl ester, (meth) acrylic acid butyl ester, (meth) acrylic acid 2-ethylhexyl ester and the like can be mentioned, and bisphenol A polyoxyethylene dimethacrylate and polypropylene glycol diacrylate are preferable. These compounds may be used alone or in combination of two or more.

The film property imparting polymer used in the present invention is
Although not particularly limited, it is a copolymer obtained by vinyl copolymerization, and it is essential to have a carboxyl group. From the viewpoint of adjusting the viscosity of the photosensitive resin composition, the film property imparting polymer is preferably a crystalline polymer having a crystallization temperature of 30 to 80 ° C. Further, the crystalline polymer has the general formula (I)

[Chemical 2] (In the formula, R represents a hydrogen atom or a methyl group, and n is 12 to
It is preferably a polymer obtained by copolymerizing a monomer represented by the formula (24 is an integer of 24). For the synthesis of the film property imparting polymer, (a) acrylic acid, methacrylic acid, fumaric acid,
A vinyl polymerizable monomer having a carboxyl group such as cinnamic acid, crotonic acid, and itaconic acid, (b) a monomer represented by the general formula (I), (c) a monomer other than the above, and methyl (meth). Acrylate, ethyl (meth) acrylate, n-
Propyl (meth) acrylate, butyl (meth) acrylate, lauryl (meth) acrylate, 2-ethylhexyl (meth) acrylate, vinyltoluene, N-vinylpyrrolidone, α-methylstyrene, 2′-hydroxyethyl methacrylate, 2-hydroxyethyl Vinyl polymerizable monomers such as acrylate, acrylamide, acrylonitrile, dimethylaminoethyl methacrylate and dimethylaminoethyl acrylate are used.

The amount of component (a) used is preferably 5 to 40% by weight, more preferably 10 to 30% by weight. If the amount of the component (a) is less than 5% by weight, the alkali developability tends to be poor, and if it exceeds 40% by weight, the developer resistance tends to decrease. The amount of component (b) used is 3
When a cross-linking agent having a melting point of 0 to 80 ° C. is used, the content is preferably 0 to 95% by weight, and when a cross-linking agent having a melting point of 30 to 80 ° C. is not used, a high molecular weight polymer having a crystal of 30 to 80 ° C. It is preferably 40% by weight or more, and more preferably 50% by weight or more, in order to have the oxidization temperature. Further, the carbon number n in the general formula (I) of the component (b) is 1
It is 2 to 24, and if the carbon number n is less than 12, the crystallization temperature may be less than 30 ° C. or the crystallinity may not be exhibited, and if it exceeds 24, the crystallization temperature may be higher than 80 ° C. is there. The amount of component (c) used is (a),
It is appropriately determined so that the total amount of the components (b) and (c) is 100% by weight.

The weight average molecular weight of the film-forming polymer is preferably 10,000 to 300,000, more preferably 20,000 to 150,000. When the weight average molecular weight is too small, flexibility and tenting property tend to deteriorate, and when it is too large, developability,
The shape of the peeled piece tends to deteriorate. The above-mentioned film property imparting polymer is used alone or in combination of two or more, but when a crosslinking agent having a melting point of 30 to 80 ° C. is not used, a film property imparting property of 30 to 80 ° C. is obtained. A polymer is an essential component, and the total amount of film-forming polymer is 5
It is preferably used in an amount of not less than 10% by weight, more preferably not less than 10% by weight. If the proportion of the crystalline polymer is less than 5% by weight, it tends to be difficult to sufficiently increase the viscosity difference between 30 ° C. and 80 ° C. of the photosensitive resin composition.
The photosensitive resin composition of the present invention contains a crosslinking agent at 30 to 80 ° C.
It is preferable that the film-forming polymer contains a compound having a melting point and the film-forming polymer has a crystallization temperature of 30 to 80 ° C. from the viewpoint of viscosity adjustment.

The photopolymerization reaction initiator used in the present invention is not particularly limited, and conventionally known ones can be used. For example, benzophenones such as benzophenone, 4,4′-dimethylaminobenzophenone, 4,4′-diethylaminobenzophenone and 4,4′-dichlorobenzophenone, anthraquinones such as 2-ethylanthraquinone and t-butylanthraquinone, 2- One or more of chlorothioxanthone, benzoin ethyl ether, benzoin isopropyl ether, benzyl, 2,4,5-triallylimidazole dimer (rophin dimer) and the like are used. The amount of photopolymerization initiator used is
The amount is 0.01 to 20 parts by weight, and more preferably 0.05 to 10 parts by weight, based on 100 parts by weight of the total amount of the film-forming polymer and the crosslinking agent. If the amount used is too small, sufficient photosensitivity cannot be obtained, and if the amount is too large, the light absorption on the surface of the composition during exposure increases and the internal photocuring becomes insufficient. Incidentally, the photosensitive resin composition according to the present invention,
Dyes, plasticizers, pigments, flame retardants, stabilizers and the like can be added as required. It is also possible to use an adhesion promoter.

Next, the photosensitive element of the present invention will be described in detail. The photosensitive element of the present invention is produced by a known method, for example, a photosensitive resin composition is uniformly dissolved in an organic solvent such as methyl ethyl ketone, toluene and methylene chloride, and this solution is knife-coated on a support film. , Roll coating, spray coating, etc.
After drying, it is obtained by laminating a peelable cover film. The thickness of the photosensitive layer of the photosensitive element is usually 10 to 100 μm. Further, the amount of residual solvent in the photosensitive layer is preferably suppressed to 2% by weight or less in order to maintain the characteristics.

The support film used in the present invention preferably has the heat resistance and solvent resistance required for the production of the photosensitive element, such as polyester film, polyimide film, polyamide film, polypropylene film, polystyrene film. Known films are used. A known film such as a polyethylene film or a polypropylene film is used as the peelable cover film, and the adhesive force between the photosensitive resin composition and the cover film is larger than the adhesive force between the photosensitive resin composition and the support film. Anything that has less force is sufficient. The photosensitive element of the present invention is usually wound and supplied in a roll shape, and after peeling off the cover film, it is heated by a heating roll or the like to be laminated on a copper clad laminate or the like. Thereafter, in a known method, for example, the photosensitive layer laminated through a negative mask with actinic rays is imagewise exposed, developed, and more preferably exposed with actinic rays to form a resist pattern on the copper clad laminate. It

Further, the solution of the photosensitive resin composition of the present invention is directly applied to a copper clad laminate or the like by a method such as a dip coating method or a flow coating method, and the solvent is dried and then directly or with an active light such as a polyester film. After laminating a transparent film on
In the same manner as in the case of the photosensitive element described above, a resist pattern can be formed in the same manner as described above by imagewise exposing through a negative mask, developing, and more preferably exposing with actinic light.

[0018]

EXAMPLES Next, the present invention will be described in more detail by way of examples, but the present invention is not limited thereto.

(Production of Crystalline Polymer) Synthesis Example 1 500 ml of toluene was placed in a flask and heated to 85 ° C.
It was left for 1 hour. After that, 16.6 g of acrylic acid, 2-
A solution prepared by dissolving 14.0 g of ethylhexyl acrylate, 70.8 g of stearyl acrylate and 0.20 g of azobisisobutyronitrile in 31.2 g of toluene was added dropwise over 4 hours for reaction. Next, add 7.1 g of methyl cellosolve, keep warm for 2 hours, and add 0.6 g of acrylic acid.
Further, a solution prepared by dissolving 0.54 g of azobisisobutyronitrile in 4.8 g of toluene was added to the reaction solution, and the mixture was kept warm for 2 hours. Then, azobisisobutyronitrile 0.
A solution of 024 g dissolved in 1.2 g of methyl cellosolve was added and kept warm for 5 hours.
a solution of 0.2 g of methyl cellosolve dissolved therein,
Upon cooling, a crystalline polymer (K1) was obtained.

Synthesis Example 2 500 ml of toluene was placed in a flask and heated to 85 ° C.,
It was left for 1 hour. Then, ethyl acrylate 20.0
g, stearyl acrylate 70.0 g, acrylic acid 1
A solution prepared by dissolving 0.5 g and 0.20 g of azobisisobutyronitrile in 31.2 g of toluene was added dropwise over 4 hours for reaction. After keeping the temperature for 2 hours, a solution prepared by dissolving 0.6 g of hydroxyethyl acrylate and 0.54 g of azobisisobutyronitrile in 4.8 g of toluene was added to the reaction solution, and the temperature was kept for another 2 hours. Then, a solution prepared by dissolving 0.024 g of azobisisobutyronitrile in 1.2 g of toluene was added and kept warm for 5 hours, and then a solution prepared by dissolving 0.01 g of hydroquinone in 0.2 g of toluene was added and cooled, A crystalline polymer (K2) was obtained. The crystalline polymers (K1) and (K2) each have a nonvolatile content of 37.
8 wt% and 40.5 wt% and the weight average molecular weights were 76,000 and 78,000, respectively. Further, the crystallization temperature of the non-volatile component is 41 ° C. for (K1),
2) was 40 ° C.

(Production of Amorphous Polymer) Synthesis Example 3 500 ml of a solution of methyl cellosolve / toluene = 3: 2 (weight ratio) (hereinafter referred to as solution A) was placed in a flask,
The temperature was raised to 85 ° C. and left for 1 hour. Then, 23.7 g of methacrylic acid, 46.8 g of methyl methacrylate, 31.2 g of ethyl acrylate, 1.5 g of 2-ethylhexyl acrylate and 0.17 g of azobisisobutyronitrile were dissolved in 31.2 g of solution A. It was added dropwise over 4 hours and reacted. Next, 7.1 g of methyl cellosolve was added, and the mixture was kept warm for 2 hours. A solution prepared by dissolving 0.6 g of methacrylic acid and 0.54 g of azobisisobutyronitrile in solution A 4.8 g was added to the reaction solution and kept warm for another 2 hours. .
Then, a solution prepared by dissolving 0.024 g of azobisisobutyronitrile in 1.2 g of methyl cellosolve was added, and 5
After keeping the temperature for a while, a solution of 0.01 g of hydroquinone in 0.2 g of methyl cellosolve was added and cooled. The obtained polymer had a nonvolatile content of 38.5% by weight and a weight average molecular weight of 84,000. The weight average molecular weight is a value measured by gel permeation chromatography and converted using a calibration curve of standard polystyrene.

(Production of Photosensitive Element) Examples 1 to 17 and Comparative Examples 1 to 4 As the crosslinking agent having a melting point at 30 to 80 ° C., the crosslinking agent shown in Table 1 is used, and the melting point is less than 30 ° C. Has BPE-1
0 (bisphenol A polyoxyethylene dimethacrylate, manufactured by Shin Nakamura Chemical Co., Ltd.) was used. Table 2 and Table 3
And a photosensitive resin composition solution was prepared according to the formulation (unit is parts by weight) shown in Table 4, and each solution was applied to a polyethylene terephthalate film (PET) having a thickness of 20 μm so that the film thickness after drying would be 40 μm. Worked, dried, thickness 35μm
To obtain a photosensitive element.

[0022]

[Table 1]

[0023]

[Table 2]

[0024]

[Table 3]

[0025]

[Table 4]

The following tests were conducted on the obtained photosensitive element, and the obtained results are shown in Table 5, Table 6 and Table 7.

(1) Contamination of heated rolls Lamination speed is set to 1.5 m / min, roll temperature is set to 110 ° C. and roll cylinder pressure is set to 4 kgf / cm ² , and width is 60 cm.
20 m of the photosensitive element of No. 1 was sequentially laminated on a substrate of 50 cm × 50 cm, the surface of the heating roll was observed, and the presence or absence of adhesion of the photosensitive resin composition was examined. The results are shown in Tables 5, 6, and 7.

(2) Viscosity The photosensitive element was continuously laminated 50 times on a substrate and punched with a ring having a diameter of 7 mm to prepare a sample piece having a thickness of 2 mm and a diameter of 7 mm. This sample is 30 ℃ and 80 ℃
The load of 20 g and 2 g was applied in the thickness direction, and the rate of decrease in thickness was determined. The viscosity is calculated from this decreasing rate using the relational expression for the Newtonian fluid (the following expression),
The results are shown in Table 5, Table 6 and Table 7.

[Equation 1]

(3) Follow-up property 1 on the surface of a copper foil of a glass epoxy base material (MCL-E-61 manufactured by Hitachi Chemical Co., Ltd.) on which a copper foil having a thickness of 35 μm is laminated.
A plurality of scratches having a length of 0 cm were formed by sequentially deepening the depth of each scratch (1 to 20 μm). These scratches were formed by changing the load using a continuous load type scratching device (manufactured by HEIDON). Next, a photosensitive element was laminated on the copper surface under the conditions of a laminating speed of 1.5 m / min, a roll temperature of 110 ° C. and a roll cylinder pressure of 4 kgf / cm ² . Next, a negative mask for forming a negative image having a line width of 100 μm was placed in a direction intersecting at right angles with the length direction of the scratch on the substrate and exposed with a high pressure mercury lamp. Then, PET
Was removed and development processing was carried out to obtain a resist image on the substrate. Further, a cupric chloride etching solution (50 ° C., spraying pressure 3 kgf / cm ² ) was sprayed for 60 seconds to dissolve the copper in the portion not protected by the resist, thereby forming a copper line on the substrate. If the photosensitive element does not follow the scratches on the substrate, there is a gap between the resist and the substrate, so the etching solution penetrates at the intersection of the resist and the scratches, copper dissolves, and the copper line connects. It will not be done and will be disconnected. The flaw depth (μm) at which the disconnection starts was taken as the followability, and the results are shown in Tables 5, 6, and 7.

(4) Exudation of Photosensitive Resin Composition A photosensitive element 50 m is wound into a roll and is allowed to stand at 30 ° C. for 1 hour.
After leaving for a month, the presence or absence of seepage from the roll end surface of the photosensitive resin composition was observed, and the results are shown in Tables 5, 6 and 7.

(5) Fragment Generation Fragment generation of the photosensitive resin composition was observed when the photosensitive element was cut by a laminator cutter, and the results are shown in Table 5.
The results are shown in Table 6 and Table 7.

[0032]

[Table 5]

[0033]

[Table 6]

[0034]

[Table 7]

As shown in Table 5, Table 6 and Table 7, the viscosity of the photosensitive resin composition is in the range of 20 to 100 MPa · sec at 30 ° C. and in the range of 10 to 70 kPa · sec at 80 ° C. By doing so, the photosensitive resin composition does not exude from the roll end surface of the photosensitive element, and excellent followability can be obtained. Further, it can be seen that such a photosensitive resin composition can be obtained, for example, by using one or both of a crystalline polymer having a melting point at 30 to 80 ° C. and a crosslinking agent.

[0036]

In the photosensitive element using the photosensitive resin composition according to the present invention, the photosensitive resin composition does not exude from the roll end portion of the photosensitive element at room temperature,
In addition, since it exhibits high unevenness followability when laminated on a substrate or the like, it is possible to improve the production yield when a printed wiring board or the like is produced using a substrate or the like having a rougher surface than before.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI Technical indication location G03F 7/033 H05K 3/06 H 3/18 D 7511-4E (72) Inventor Shigeo Tachiki Ibaraki prefecture 4-13-1 Higashimachi, Hitachi-shi Hitachi Chemical Co., Ltd. Ibaraki Research Institute (72) Inventor Junichi Imaizumi 1150 Goshomiya, Shimodate-shi, Ibaraki Hitachi Chemical Co., Ltd. Yuuki Factory (72) Inventor Matsuo Kato 1150 Goshonomiya, Shimodate City, Ibaraki Prefecture Inside Hitachi Chemical Co., Ltd. Yuki Plant (72) Inventor Kazutaka Masaoka 4-13-1 Higashimachi, Hitachi City, Ibaraki Hitachi Chemical Co., Ltd. Yamazaki Plant

Claims (7)

[Claims] 1. A photopolymerization which forms free radicals by 40 to 80 parts by weight of a film-forming polymer composed of a carboxyl group-containing vinyl copolymer, 20 to 60 parts by weight of a cross-linking agent having an ethylenically unsaturated bond, and an actinic ray. Reaction initiator 0.
A photosensitive resin composition containing 01 to 20 parts by weight (used in such an amount that the total amount of the film property imparting polymer and the crosslinking agent is 100 parts by weight), having a viscosity at 30 ° C. of 20 to 100 MPa.
A photosensitive resin composition having a viscosity of 10 to 70 kPa · sec at 80 ° C for sec. 2. A cross-linking agent having an ethylenically unsaturated bond,
The photosensitive resin composition according to claim 1, which contains a compound having a melting point of 30 to 80 ° C. 3. A compound having a melting point of 30 to 80 ° C. is tris (acryloxyethyl) isocyanurate, methoxy polyethylene glycol 1000 methacrylate, polyethylene glycol 1000 dimethacrylate, 4-
(2,2,6,6-tetramethylpiperidinyl) methacrylate, bisphenol epoxy acrylate, urethane acrylate monomer (molecular weight of 1,000 or more)
The photosensitive resin composition according to claim 2, which is one kind or two or more kinds of the above. 4. The film property imparting polymer comprising a carboxyl group-containing vinyl copolymer contains a crystalline polymer having a crystallization temperature of 30 to 80 ° C.
The photosensitive resin composition described. 5. The crystalline polymer has the general formula (I): (In the formula, R represents a hydrogen atom or a methyl group, and n is 12 to
The photosensitive resin composition according to claim 4, which is a polymer obtained by copolymerizing a monomer represented by the formula (24 is an integer of 24). 6. A cross-linking agent having an ethylenically unsaturated bond,
A polymer containing a compound having a melting point of 30 to 80 ° C., and a film-forming polymer made of a carboxyl group-containing vinyl copolymer containing a crystalline polymer having a crystallization temperature of 30 to 80 ° C. The photosensitive resin composition according to claim 1, which is 7. A photosensitive element obtained by laminating a layer of the photosensitive resin composition according to claim 1, 2, 3, 4, 5 or 6 on a support.