JP3444795B2 - Photosensitive resin composition - Google Patents

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a photosensitive resin composition containing a polyamic acid as a main component, and more specifically, a polyamic acid which is a precursor of a polyimide having a specific structure has a specific structure ( By blending a (meth) acrylate compound and a photopolymerization initiator in a specific ratio, it has good heat resistance, adhesiveness, electrical characteristics, etc., and further has good elongation characteristics. The present invention relates to a liquid resist ink composition, a cover coating agent, and an insulating film for a multilayer printed circuit board, which are most suitable for the production of the above, which can be developed with an alkaline aqueous solution.

[0002]

2. Description of the Related Art Conventionally, in printed wiring boards, a resist pattern is formed by a screen printing method using an etching resist or a plating resist, and then a metal foil is etched or plated to a desired conductor circuit pattern. Had formed. For the purpose of preventing oxidation of the conductor circuit pattern and maintaining the insulating property, a thermosetting resin composition or a photocurable resin composition is applied on the conductor circuit pattern by a screen printing method to form a film. Recently, miniaturization of conductor circuits is progressing in order to increase the pattern density. For this reason, it is widely used to form the resist pattern using the photo method.

The etching or plating resist pattern formed by the photo method has higher positional accuracy and dimensional accuracy than the screen printing method. Due to the miniaturization of the conductor circuit pattern and the improvement of the position accuracy, the miniaturization of the mounting parts, and the fine pitch of the leads of the IC package, the formation of the insulating film such as the solder resist film also required the improvement of the image accuracy and the position accuracy. . Therefore, in recent years, a method of forming a solder resist film or an insulating film by using the photo method has been widely used as a method of forming a film with high accuracy.

In the photo method, a photosensitive resin composition is applied to a desired size and then dried if necessary to form a photosensitive film. A negative photomask is placed on this photosensitive film, and exposure and baking are performed with active rays such as ultraviolet rays. The actinic rays that have passed through the transparent parts of the photomask cure the photosensitive film. The unexposed part is peeled off by development,
Remove the photosensitive film. The photosensitive film formed by the above photo method is further cured by heat curing or actinic rays to form a solder resist film or an insulating film, but since the formed image can be formed with an accuracy extremely close to that of a photomask, It is possible to easily obtain accurate images and positional accuracy.

However, this method requires a developing step later. In the development, the uncured portion of the unexposed portion was dissolved and peeled off with an organic solvent to be removed. The solvent is 1,1,1
A highly toxic solvent such as trichloroethane or a flammable solvent is generally used, and a photo solder resist using an alkaline aqueous solution as a developer has been desired from the viewpoint of work safety. Therefore, research on an alkaline aqueous solution development type photo solder resist has become popular in recent years, and some compositions have been disclosed. For example, Japanese Patent Publication Sho 56
JP-A-40329 discloses a photosensitive resin composition containing a base polymer as a reaction product obtained by adding an unsaturated monocarboxylic acid to an epoxy resin and further adding a polybasic acid anhydride. Japanese Patent Laid-Open No. 61-243869 discloses that
A photosolder resist composition is disclosed in which a reaction product obtained by adding a polybasic acid anhydride to a novolac type epoxy acrylate or the like is used as a base polymer and an alkaline aqueous solution is used as a developing solution. However, the solder resist film obtained from the above composition is insufficient in heat resistance, solvent resistance and chemical resistance, and the properties relating to insulation and dielectric constant are not sufficient. Also, due to its poor flexibility,
Not applicable to flexible circuit boards.

Further, a polyimide obtained by heat-treating a polyamic acid which is a polyimide precursor is
Due to its excellent heat resistance and dielectric properties, it has been proposed as a photosensitive polyimide precursor which has been used as a protective film for ICs and an interlayer insulating film, and can form a pattern directly by exposure and development (Japanese Patent Laid-Open No. Sho 60). -228537, JP-A-59-52822). However, these photosensitive polyimides use organic solvents for development, and from the viewpoint of work safety, photosensitive polyimides that can be developed with an alkaline aqueous solution are desired. Further, the photosensitive polyimide has insufficient adhesion with a conductor such as copper foil,
In order to obtain a sufficient adhesive force, some treatment such as roughening the conductor surface is required. Further, it does not have sufficient elongation of the cured film to be applied to the flexible circuit board.

[0007]

It is possible to develop with an alkaline aqueous solution such as an aqueous solution of sodium hydroxide or an aqueous solution of sodium carbonate, and it is possible to obtain a sufficiently hardened film at the time of printing an image by exposure, and to perform a heat treatment after the development. As the film characteristics after imidization with, excellent heat resistance,
A photosensitive resin composition suitable for use as a photosensitive resin composition or photo solder resist that exhibits flexibility by its adhesiveness to a conductor, electrical characteristics, and good elongation characteristics, and a cover coating agent for flexible circuit boards. Is to provide. It is an object of the present invention to provide a metal processed product which is excellent in heat resistance, oxidation resistance and electric insulation properties by using these photosensitive films.

[0008]

That is, the present invention is
(1) (A) The following formula (1) [Chemical formula 3]

[0009]

[Chemical 3] (In the formula, R is the formula (2)

[0010]

[Chemical 4] Represents ), The logarithmic viscosity thereof (N, N-dimethylacetamide solvent, concentration 0.5
g / 100 ml, measured at 35 ° C.) is 0.3 to 1.0 dl
/ G of polyamic acid, relative to 100 parts by weight,
(B) a (meth) acrylate compound containing an alcoholic hydroxyl group and having at least three or more photopolymerizable C-C unsaturated double bonds, 10 to 50 parts by weight, and (C)
A photosensitive resin composition prepared by blending 10 to 50 parts by weight of a polyalkylene glycol di (meth) acrylate compound and (D) a photopolymerization initiator as essential components, (2)
The photosensitive resin composition described in (1) is added to a nitrogen-containing organic solvent 1
A photosensitive resin composition diluted with a mixed solvent containing 10 to 1000 parts of a glycol ether organic solvent, relative to 00 parts, (3) The elongation of the film after curing is 20% or more (1) The photosensitive resin composition described above, and (4)
A processed product having a photosensitive film formed by applying the photosensitive resin composition according to (1) to a metal, a plastic, or a ceramic and drying the composition.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The polyamic acid used in the present invention, that is, a polymer having a repeating unit represented by the above formula (1), contains 1,3-bis (3-aminophenoxy) benzene as an aromatic diamine. 3,3'-4,4'-biphenyltetracarboxylic dianhydride is used as the aromatic dianhydride. These can be produced by condensation in an organic solvent (JP-A-61-1434).
No. 77 publication).

In the above condensation reaction, the reaction temperature is usually 10 to 60 ° C., preferably 20 to 50 ° C., and the pressure is not particularly limited, and it can be sufficiently carried out at normal pressure. The reaction time varies depending on the type of organic solvent used and the reaction temperature, but is usually a time sufficient to complete the production of polyamic acid, that is, 4 to 24 hours. In the present invention, the polyamic acid obtained as described above needs to have an inherent viscosity of 0.3 to 1.0 dl / g. Here, the logarithmic viscosity means the following mathematical expression (1) [Equation 1]

[0013]

## EQU1 ## Logarithmic viscosity = ln (η / η ₀ ) / C (1) (wherein is a natural logarithm, η is a solution prepared by dissolving 0.5 g of polyamic acid in 100 ml of N, N-dimethylacetamide as a solvent). Measured at 35 ° C., η ₀ is 3 of the solvent
The viscosity measured at 5 ° C. and C are the solution concentrations of the polymer in g of polyamic acid per 100 ml of the solvent. ) Is the value calculated in.

The polyamic acid has an inherent viscosity of 0.3 dl
If it is less than / g, the degree of polymerization of the polyamic acid is small, and the coating film in the exposed area cannot have sufficient strength during development. On the other hand, when the logarithmic viscosity exceeds 1.0 dl / g, the degree of polymerization of the polyamic acid becomes too large, and unexposed areas are poorly dissolved during development. This logarithmic viscosity can be arbitrarily adjusted by changing the molar ratio of the aromatic diamine and the aromatic dianhydride.

The solvent used in the present invention is a nitrogen-containing organic solvent. As the nitrogen-containing organic solvent, N, N-dimethylformamide, N, N-dimethylacetamide, N-
Methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone and the like can be mentioned.

In the present invention, it is preferable to use a nitrogen-containing organic solvent and a glycol ether organic solvent in combination.

As the glycol ether type organic solvent,
Examples thereof include ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol methyl ethyl ether, triethylene glycol dimethyl ether, and triethylene glycol diethyl ether.

Two or more kinds of the nitrogen-containing organic solvent or glycol ether organic solvent may be mixed and used. More preferably, the mixing ratio of the nitrogen-containing organic solvent and the glycol ether-based organic solvent is such that the glycol ether-based organic solvent is from 10 parts by weight to 1000 parts by weight, and more preferably 20 parts by weight relative to 100 parts by weight of the nitrogen-containing organic solvent.
The range is from 500 parts by weight to 500 parts by weight. If the amount of the glycol ether-based organic solvent is less than 10 parts by weight, cracks will occur in the coating film during alkali development. Further, if the amount of the glycol ether type organic solvent exceeds 1000 parts by weight, it becomes difficult to dissolve the polyamic acid, which is not preferable.

Examples of the (meth) acrylate compound containing an alcoholic hydroxyl group and having at least three or more photopolymerizable C-C unsaturated double bonds used in the present invention include pentaerythritol triacrylate and pentaerythritol triacrylate. Examples thereof include erythritol trimethacrylate, dipentaerythritol pentaacrylate, and dipentaerythritol pentamethacrylate. Compatibility with the polyamic acid, curability during exposure, and unexposed to an alkaline aqueous solution during development From the solubility of parts, pentaerythritol triacrylate is most preferable.

The amount of the (meth) acrylate compound to be blended is 10 to 50 parts by weight based on 100 parts by weight of the polyamic acid. If the amount is less than 10 parts by weight, the film after exposure is not sufficiently cured, and the unexposed portion is not completely dissolved during alkali development, resulting in residual development. If it exceeds 50 parts by weight, the flexibility of the exposed area is impaired, and the elongation of the film after exposure is significantly reduced.

The polyalkylene glycol di (meth) acrylate compound used in the present invention has the following formula:
Examples include compounds represented by (Formula 3) [Chemical Formula 5] to (Formula 8) [Chemical Formula 10]. (Formula 3) [Chemical Formula 5] (In the formula, n is 2 to 12.)

[0022]

[Chemical 5] (Formula 4) [Chemical Formula 6] (In the formula, n is 2 to 12.)

[0023]

[Chemical 6] (Formula 5) [Chemical Formula 7] (In the formula, n is 2 to 12.)

[0024]

[Chemical 7] (Formula 6) [Chemical formula 8] (In the formula, n is 2 to 12.)

[0025]

[Chemical 8] (Formula 7) [Formula 9] (In the formula, n is 2 to 12.)

[0026]

[Chemical 9] (Formula 8) [Chemical Formula 10] (In the formula, n is 2 to 12.)

[0027]

[Chemical 10] The amount of the polyalkylenedi (meth) acrylate compound added is 10 to 50 parts by weight based on the polyamic acid. If it is less than 10 parts by weight, the flexibility of the exposed portion is insufficient and the elongation of the film after exposure is lowered. If it exceeds 50 parts by weight, the heat resistance is significantly impaired.

The photopolymerization initiator used in the present invention is a known one, specifically, benzophenone, Michler's ketone,
Benzoin, Benzoin ethyl ether, Benzoin butyl ether, Benzoin isobutyl ether, 2,2
-Dimethoxy-2-phenylacetophenone, 2-hydroxy-2-phenylacetophenone, 2-hydroxy-
2-Methylpropiophenone, 2-hydroxy-4-isopropyl-2-methylpropiophenone, 2-ethylanthraquinone, 2-t-butylanthraquinone, diethylthioxanthone, chlorothioxanthone, benzyl, benzyldimethylketal, 1-hydroxycyclohexyl. Examples thereof include phenyl ketone, benzoylbenzoic acid, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, and 2,4,6 trimethylbenzoyldiphenylphosphine oxide.

Further, an equimolar addition product of benzoin and ethylene oxide, a 2-fold to 4-fold mole addition product,
An equimolar addition product of benzoin and propylene oxide or 2
4-fold mole addition product to 4-fold mole addition product, α-allylbenzoin, equimolar addition product of 1-hydroxycyclohexylphenyl ketone and ethylene oxide, 2-fold addition product to 4-fold addition product, 1-hydroxycyclohexylphenyl ketone Equimolar adduct of propylene oxide, 2-molar to 4-molar adduct, benzoylbenzoic acid and ethylene glycol equimolar reaction product, benzoylbenzoic acid and propylene glycol equimolar reaction product, hydroxybenzophenone and ethylene oxide equimolar product Addition product, 2-fold addition product to 4-fold addition product, equimolar addition product of hydroxybenzophenone and propylene oxide, 2-fold addition product, 4-fold addition product, 4- (2-hydroxyethoxy) phenyl- (2- Hydroxy-2-propyl) ketone, 4- (2-a B oxy ethoxy) - phenyl -
(2-hydroxy-2-propyl) ketone, 4- (2-
Hydroxyethoxy) phenyl- (2-hydroxy-2
-Propyl) ketone and ethylene oxide equimolar adduct, 2-molar adduct to 4-molar adduct, 4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-
Propyl) ketone and propylene oxide equimolar addition product, 2-fold molar addition product to 4-fold molar addition product, 1- (4-isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 1- (4 -Decylphenyl) -2-
Hydroxy-2-methylpropan-1-one and the like can be mentioned. These are used alone or in combination of two or more.

Further, a known photopolymerization initiation auxiliary agent may be used in combination. As these photopolymerization initiation aids, specifically, triethanolamine, diethanolamine, ethanolamine, tripropanolamine, dipropanolamine,
Propanolamine, ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate and the like can be mentioned. The photopolymerization initiation aid is used alone or in combination of two or more. The blending amount of the photopolymerization initiator with respect to the total solid content of the photosensitive resin composition is 0.1 wt% to 20 wt%,
More preferably, it is 1.0 wt% to 10 wt%.

A method of forming a solder resist film or an insulating film on the surface of a metal or a metal laminated plate using the photosensitive resin composition can be easily performed by using a known roll coater, screen coating, bar coater or the like. Can be applied to. The applied photosensitive resin composition becomes a photosensitive film by volatilizing an organic solvent, but drying may be performed by a known method, for example, using a hot air dryer, a far infrared ray, a near infrared ray, or the like. A photosensitive film can be formed by drying at ~ 150 ° C for 10 to 60 minutes.

The film thickness of the photosensitive film is usually 5 to 200 μm.
And preferably 15 to 100 μm. Film thickness is 5 μm
If it is less than 200 μm, the insulation reliability is poor, and if it exceeds 200 μm, the exposure sensitivity is lowered and the developing time is long, which is not preferable. Further, the photosensitive resin composition of the present invention is not only a material for forming a solder resist film or an insulating film, but is also applied to a colorless and transparent film such as polyethylene, polypropylene or polyester to obtain a photosensitive film. be able to.

The photosensitive film has a film thickness of 10 described above.
A film having a thickness of up to 100 μm can be coated by a known method such as a reverse roll coater, a gravure roll coater, a comma coater or a curtain coater. Drying can be carried out at a temperature of 50 to 120 ° C. with a dryer using hot air drying, far infrared rays, or near infrared rays, and more preferably 60 to 1
A photosensitive film can be obtained by drying at 00 ° C. for 10 to 60 minutes. The film thickness of the photosensitive resin composition at this time is 5 to 200 μm, more preferably 15 to 1
It is 00 μm.

If the film thickness is less than 5 μm, the insulation reliability is insufficient, and if it exceeds 200 μm, the exposure sensitivity is lowered and the development takes a long time. In addition, in order to obtain a solder resist film or an insulating film using the above-mentioned photosensitive film, a known method such as a flat plate press or a roll press is used while heating at 40 to 150 ° C. and 98 to 490 kP.
By thermocompression bonding with a (1 to 5 Kgf / cm ² ), the photosensitive film can be formed on the surface of the metal plate or the metal laminated plate.

In this way, the photosensitive film is exposed using a normal photomask. Examples of the actinic ray used at this time include ultraviolet rays, electron beams, and X-rays. Among them, ultraviolet rays are more preferable, and the light source thereof includes, for example, a low-pressure mercury lamp, a high-pressure mercury lamp, Examples include ultra-high pressure mercury lamps and halogen lamps.

After development, when development is performed using a developing solution, a dipping method or a spray method can be used. As the developer, an alkaline aqueous solution such as an aqueous sodium hydroxide solution or an aqueous sodium carbonate solution is used. After development, it is desirable to rinse with an acidic aqueous solution such as diluted hydrochloric acid or diluted sulfuric acid.

The pattern obtained by the development is then heated to be converted into a polyimide pattern. The heat treatment is continuously or stepwise performed at a temperature of 150 to 450 ° C. for 0.1 to 5 hours.

[0038]

EXAMPLES The present invention will be specifically described below with reference to Examples and Comparative Examples, but the present invention is not limited thereto. [Synthesis Example 1] (Polyamic acid PA1) Reactor (with stirrer, reflux condenser and nitrogen introduction tube)
Medium, under nitrogen atmosphere, N, N-dimethylacetamide 13
5 g, diethylene glycol dimethyl ether 135 g
1,3-bis (3-aminophenoxy) benzene 5
3.29 g (0.1825 mol) was dissolved, and while stirring this, 53.214 g (0.1810 mol) of 3,3′-4,4′-biphenyltetracarboxylic dianhydride was dried as a solid. Added in small portions. During this period, the temperature of the reactor was maintained at 25 to 30 ° C., and stirring was continued for 20 hours after the addition under a nitrogen atmosphere to obtain a polyamic acid having a solid content of 30%. Table 1 shows the logarithmic viscosity of this polyamic acid.

[Synthesis Example 2] (Polyamic acid PA2) [0039] Instead of the 3,3'-4,4'-biphenyltetracarboxylic dianhydride of Synthesis Example 1, pyromellitic dianhydride was used. The same operation as in Synthesis Example 1 was carried out to obtain a polyamic acid. Table 1 shows the logarithmic viscosity of this polyamic acid.

[Synthesis Example 3] (Polyamide acid PA3) Synthesis Example 1 except that 4,4'-diaminodiphenyl ether was used in place of 1,3'-bis (3-aminophenoxy) benzene in Synthesis Example 1 The same operation as described in (1) above was performed to obtain a polyamic acid. The logarithmic viscosity of this polyamic acid is shown in Table 1.
Shown in.

[Synthesis Examples 4 to 5] (Polyamic acid 4 to
5) The amount of 3,3′-4,4′-biphenyltetracarboxylic dianhydride in Synthesis Example 1 was 44.1 g (0.15 mol).
(PA4) or 53.655 g (0.1825 mol) (PA5)
A seed of polyamic acid was obtained. Table 1 shows the logarithmic viscosity of this polyamic acid.

[Synthesis Example 6] (Polyamic acid 6) A polyamic acid was obtained in the same manner as in Synthesis Example 1, except that the total amount of the organic solvent was changed to 270 g of N, N-dimethylacetamide. Table 1 shows the logarithmic viscosity of this polyamic acid.

[0043]

[Table 1] An example of the photosensitive resin composition of the present invention using the polyamic acid shown in the above synthesis example is shown below. [Example 1] Blending amount (parts by weight) Synthesis example 1 Polyamic acid (PA1) 200 Pentaerythritol triacrylate (Aronix M-305 manufactured by Toagosei Co., Ltd.) 24 Polyethylene glycol 200 diacrylate (NKA-200 manufactured by Shin-Nakamura Chemical Co., Ltd.) ) 6 IRUGACURE 907 (manufactured by Ciba-Geigy, hereinafter abbreviated as IGC907) 4 Kayacure DETX (manufactured by Nippon Kayaku, hereinafter abbreviated as DETX) 1

[0044] [Example 2]                                                   Compounding amount (parts by weight) Synthesis Example 1 Polyamic acid (PA1) 200 Pentaerythritol triacrylate 6 Polyethylene glycol 200 diacrylate 24 IGC907 4 DETX 1

[0045] [Comparative Example 1]                                                   Compounding amount (parts by weight) Synthesis Example 2 Polyamic acid (PA2) 200 Pentaerythritol triacrylate 24 Polyethylene glycol 200 diacrylate 6 IGC907 4 DETX 1

[0046] [Comparative Example 2]                                                   Compounding amount (parts by weight) Synthesis Example 3 Polyamic acid (PA3) 200 Pentaerythritol triacrylate 24 Polyethylene glycol 200 diacrylate 6 IGC907 4 DETX 1

[0047] [Comparative Example 3]                                                   Compounding amount (parts by weight) Synthesis Example 4 Polyamic acid (PA4) 200 Pentaerythritol triacrylate 24 Polyethylene glycol 200 diacrylate 6 IGC907 4 DETX 1

[0048] [Comparative Example 4]                                                   Compounding amount (parts by weight) Synthesis Example 5 Polyamic acid (PA5) 200 Pentaerythritol triacrylate 24 Polyethylene glycol 200 diacrylate 6 IGC907 4 DETX 1

[0049] [Comparative Example 5]                                                   Compounding amount (parts by weight) Synthesis Example 6 Polyamic acid (PA6) 200 Pentaerythritol triacrylate 24 Polyethylene glycol 200 diacrylate 6 IGC907 4 DETX 1

[0050] [Comparative Example 6]                                                   Compounding amount (parts by weight) Synthesis Example 1 Polyamic acid (PA1) 200 Pentaerythritol triacrylate 30 IGC907 4 DETX 1

[Comparative Example 7] Blending amount (parts by weight) Synthesis Example 1 Polyamic acid (PA1) 200 Polyalkylene glycol 200 diacrylate 30 IGC907 4 DETX 1 The above-mentioned photosensitive resin composition was prepared to form a conductor circuit pattern. The drawn printed wiring board was uniformly applied using a doctor blade. Then, it dried at 80 degreeC for 40 minutes, and created the sample for a test. Further, a 1 mm-thick metal plate and a 1-ounce copper foil glossy surface were coated and dried to obtain a test sample. The dried coating film thickness was adjusted so that a photosensitive film of 20 to 25 μm was obtained on the conductor circuit, the metal plate and the glossy surface of the copper foil.

Next, using a desired photomask, 3 kw
500mj / cm ^{2 on the} photosensitive film with the ultra high pressure mercury lamp
It was exposed so that the amount of light could be irradiated. The exposed photosensitive film was developed by immersing it in a developing solution adjusted to 30 ° C. with a 1.0 wt% sodium hydroxide aqueous solution for 50 seconds. In Examples 1 to 2 and Comparative Examples 1 to 2 and 6 to 7, the unexposed portion was easily peeled off with the developer to obtain the desired image. In Comparative Example 3, the exposed area was completely dissolved in the developing solution and an image could not be obtained. In Comparative Example 4, the unexposed area was not dissolved in the developing solution and an image could not be obtained. In Comparative Example 5, a desired image was obtained, but cracks were generated in the coating film. Example 1
-2 and Comparative Examples 1-2 and 6-7 were heat-processed at 250 degreeC for 10 minute (s), and the coating film was converted into polyimide.

The test samples converted into the above polyimides were evaluated by the following methods. Evaluation 1: The pencil hardness test was performed by the method described in (JIS K-5405). Evaluation 2: Adhesion after cross-cut is (JIS K-5
405). Evaluation 3: The solvent resistance test was carried out by adding a cross cut described in (JIS K-5405), and then applying 12 to acetone at room temperature.
After soaking for a period of time, the remaining amount on the cross was measured. Evaluation 4: In the chemical resistance test, after inserting the cross-cut described in (JIS 5405), it was dipped in a 10 wt% hydrochloric acid aqueous solution at 60 ° C. for 12 hours, and the remaining amount of the cross-cut was measured. Evaluation 5: In the chemical resistance test, after putting the cross-cut described in (JIS 5-5405), it was immersed in a 10 wt% sodium hydroxide aqueous solution at 60 ° C. for 12 hours, and the remaining amount of the cross-cut was measured. Evaluation 6: A copper foil laminate having a solder resist pattern formed of a photosensitive film was subjected to 10 in an environment of 60 ° C.-95% RH.
It was left for 0 hours. This sample was dipped in a molten solder at 280 ° C. for 20 seconds, and it was confirmed whether the copper foil and the solder resist film were peeled off or swollen. Evaluation 7: A test sample formed on a 0.2 mm copper plate was subjected to a bending test at an angle of 90 ° to confirm the presence or absence of cracks in the coating. Evaluation 8: 1 ounce, in a test sample formed on a rolled copper foil glossy surface, the copper foil was then etched to a width of 2 mm, and the strength when the coating and the 2 mm width copper foil were peeled off at an angle of 90 ° The Peel strength (Kg / cm) is shown. Evaluation 9: 1 ounce, a test sample formed on a glossy surface of a rolled copper foil, and then the copper foil was entirely etched to prepare a test sample having only a film. This is 15m wide
The elongation rate (%) of the coating film when cut into test pieces of m and 150 mm in length and subjected to a tensile elongation test was shown.

Table 2 shows the evaluation results of Examples 1-2 and Comparative Examples 1-7. In Examples 1 and 2, it is possible to develop with an alkaline aqueous solution, and it has excellent adhesiveness to conductors, flexibility, chemical resistance, and film extensibility, and further, peeling and swelling do not occur due to solder heat resistance. . In Comparative Example 1,
The elongation of the film was extremely low. In Comparative Example 2,
Inadequate adhesion with conductor. In Comparative Example 6,
The elongation of the film was low. In Comparative Example 7, the heat resistance was low and peeling occurred after immersion in the solder.

[0055]

[Table 2]

[0056]

The insulating film and the solder resist film made of the photosensitive resin composition according to the present invention can be developed with an alkaline aqueous solution. In addition, by using polyamic acid as the main component, it is possible to develop the excellent heat resistance, processability, electrical characteristics, and flexibility possessed by the polyimide itself corresponding to this polyamic acid, and to form an insulating film for printed wiring boards. Best for materials. In addition, the polyamic acid exhibits thermoplasticity by having a specific structure, has a strong adhesive force to a conductor such as a metal foil, and further, by blending a specific (meth) acrylate compound, good Due to the elongation property of the film, excellent performance can be expected as an interlayer insulating material for multilayer printed wiring boards and a cover coat material for flexible circuit boards.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI H05K 3/28 H05K 3/28 D 3/46 3/46 T (56) References JP-A-6-89028 (JP, A) JP-A-7-316291 (JP, A) JP-A-9-90630 (JP, A) JP-A-5-40338 (JP, A) JP-A-5-40339 (JP, A) JP-A-5-40340 (JP, A) JP 10-207063 (JP, A) JP 10-207064 (JP, A) JP 10-39510 (JP, A) JP 5-86154 (JP, A) 58) Fields investigated (Int.Cl. ⁷ , DB name) G03F ^7/ 00-7/42

Claims (4)

(57) [Claims] 1. (A) The following formula (1) [Chemical formula 1] (In the formula, R is the formula (2) [Chemical formula 2] Represents ), The logarithmic viscosity thereof (N, N-dimethylacetamide solvent, concentration 0.5
g / 100 ml, measured at 35 ° C.) is 0.3 to 1.0 dl
/ G of polyamic acid, relative to 100 parts by weight,
(B) a (meth) acrylate compound containing an alcoholic hydroxyl group and having at least three or more photopolymerizable C-C unsaturated double bonds, 10 to 50 parts by weight, and (C)
A photosensitive resin composition comprising a polyalkylene glycol di (meth) acrylate compound, 10 to 50 parts by weight, and (D) a photopolymerization initiator as essential components. 2. A photosensitive resin composition obtained by diluting the photosensitive resin composition according to claim 1 with a mixed solvent containing 10 to 1000 parts of a glycol ether organic solvent with respect to 100 parts of a nitrogen-containing organic solvent. . 3. The photosensitive resin composition according to claim 1, wherein the cured film has an elongation percentage of 20% or more. 4. A processed product having a photosensitive film formed by applying and drying the photosensitive resin composition according to claim 1 on a metal, a plastic or a ceramic.