JPH11223943A - Resist pattern forming method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resist pattern forming method superior in adhesion with a substrate and in resistance to foaming and etching and capable of forming a resist pattern in a short time and in a high yield. SOLUTION: A photosensitive resin composition contains (a) a polymer having carboxy groups, (b) an ethylenically unsaturated compound containing a compound represented by the formula in an amount of 50-100 weight % of the total (b) component, (c) a lophine dimer in an amount of 0.5-6.0 weight % of (a)+(b), (d) a photopolymerization initiator in an amount of 0.1-10 weight % of (a)+(b), and (e) a leuco dye in an amount of 0.1-3.0 of (a)+(b). The resist pattern is formed by coating a metal surface with this resin composition to form a photosensitive layer and exposing and developing it and irradiating it with activated rays after the development. In the formula, each of R1 and R2 is, independently, an H atom or a 1-3C alkyl group, and (n) is an integer of 4-20.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a resist pattern in metal working of a printed wiring board, a lead frame, and the like. The present invention relates to a method of forming a resist pattern which is excellent in etching resistance without a conductor being sunk or permeated by etching.

[0002]

2. Description of the Related Art In recent years, a photoresist method using a photosensitive resin has been used for manufacturing a printed wiring board and the like. Most dry film resists used in the photoresist method are of an alkali developing type. After exposure, unexposed portions are developed with an alkali solution such as sodium carbonate to reduce carboxylic acid groups in the photosensitive resin composition. It becomes a carboxylate and becomes water-soluble, the unexposed portions are removed, and a resist image is formed. Using the resist image thus formed as a protective mask, a known etching process or pattern plating process is performed, and then the resist is peeled off to manufacture a printed circuit board.

However, when a pattern is formed on a metal substrate other than copper, such as a 42 alloy (iron-nickel alloy) and stainless steel, using an alkali-developing dry film resist, the metal substrate The low adhesion between the resist and the resist causes a phenomenon (etching phenomenon) of etching to the lower part of the resist during etching and a phenomenon of peeling of the resist, thereby causing a problem of a reduction in product yield. As such a solution, Japanese Patent Application Laid-Open No. 8-220
No. 776 discloses a method of processing a metal substrate using an alkaline aqueous solution-developed dry film resist, laminating a dry film resist on the metal substrate, exposing and developing, and after the development is completed, heat-treating the resist on the metal substrate by far infrared rays. Propose that. Also, JP-A-8-32826
Japanese Patent Publication No. 6 proposes irradiating an actinic ray after exposure and development.

[0004]

However, in the technology disclosed in the above-mentioned publication, the dry film resist is of an alkali developing type which is generally used, and it is still unsatisfactory in consideration of the recent advancement and refinement of technology. Instead, further improvement is desired for such resists. That is, even when a metal substrate other than copper, such as 42 alloy (iron-nickel alloy) or stainless steel, is used, the adhesiveness between the substrate and the resist is excellent, the foam is suppressed, and the conductor is not penetrated. There is a demand for a method capable of performing a resist pattern having excellent etching resistance in a short time and with a high yield.

[0005]

The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, (a) a carboxyl group-containing polymer, (b) an ethylenically unsaturated compound, and (c) a rofin dimer Body, (d) a photopolymerization initiator,
(E) In a photosensitive resin composition containing a leuco dye, a compound represented by the following formula as a component (b) is contained in an amount of 50 to 100% by weight based on the whole component (b), and further a component (a). Component (c) is added in an amount of 0.5 to 6.0 parts by weight, and component (d) is added in an amount of 0.5 to 6.0 parts by weight based on a total of 100 parts by weight of component (b).
A photosensitive resin composition (F) layer containing 1 to 10 parts by weight and 0.1 to 3.0 parts by weight of the component (e) is formed on the surface of the metal substrate, exposed and developed, and after the development is completed. The inventors have found that a method of forming a resist pattern by irradiating actinic rays meets the above-mentioned object, and have completed the present invention.

[0006]

Embedded image (Here, R ₁ and R ₂ are an alkyl group having 1 to 3 carbon atoms or hydrogen, which may be the same or different from each other. N is an integer of 4 to 20.)

In the present invention, the photosensitive resin composition (F)
It is also preferable to use it as a dry film resist having at least one layer. In the present invention, when the (c) lophine dimer is a triphenylbiimidazole, and further when (d) a compound represented by the following formula is used as a photopolymerization initiator, the effect of the present invention is markedly improved. Demonstrate.

[0008]

Embedded image (Here, R ₃ and R ₄ are hydrogen or an alkyl group, which may be the same or different from each other.)

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described specifically. The photosensitive resin composition (F) of the present invention comprises (a) a carboxyl group-containing polymer, (b) an ethylenically unsaturated compound, (c) a lophine dimer, (d) a photopolymerization initiator,
(E) a resin composition containing a leuco dye,
(A) As the carboxyl group-containing polymer, (meth)
Acrylic copolymers containing acrylic acid ester as a main component and copolymerized with an ethylenically unsaturated carboxylic acid are preferably used, and further, acrylic copolymers obtained by copolymerizing other copolymerizable monomers as necessary. It is also possible to use a copolymer. In this case, the content of each component is such that the (meth) acrylate component is 70 to 85% by weight, preferably 75% by weight.
To 82% by weight, and the amount of the ethylenically unsaturated carboxylic acid component is 15
-30% by weight, preferably 18-25% by weight, and the other copolymerizable monomer component is often 0-15% by weight.

Here, the (meth) acrylate includes methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate,
-Ethylhexyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, glycidyl (meth) acrylate, and the like. You.

As the ethylenically unsaturated carboxylic acid, for example, monocarboxylic acids such as acrylic acid, methacrylic acid and crotonic acid are preferably used.
Dicarboxylic acids such as fumaric acid and itaconic acid, or anhydrides and half esters thereof can also be used. Of these, acrylic acid and methacrylic acid are particularly preferred.

Other copolymerizable monomers include, for example, tetrahydrofurfuryl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, glycidyl methacrylate, 2,2,2-trifluoroethyl ( (Meth) acrylate, (meth) acrylamide, 2,2,3,3-tetrafluoropropyl (meth) acrylate, acrylamide, diacetone acrylamide, styrene, α-methylstyrene, vinyltoluene, vinyl acetate, alkyl vinyl ether, (meth) Acrylonitrile and the like can be mentioned.

In addition to the above, a polyester resin, a polyamide resin, a polyurethane resin, an epoxy resin and the like can be used in combination with the carboxyl group-containing polymer (a) thus obtained. The carboxyl group-containing polymer has a weight average molecular weight of 10,000 to 300,000, preferably 10,000 to 150,000, more preferably 300 to 300,000.
When the molecular weight is less than 10,000, cold flow is liable to occur. Conversely, when the molecular weight exceeds 300,000, development is difficult, resulting in a decrease in resolution and poor peelability at the time of resist peeling.

(B) As the ethylenically unsaturated compound,
Ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butylene glycol di (meth) acrylate, neopentyl Glycol di (meta)
Acrylate, 1,6-hexane glycol di (meth)
Acrylate, trimethylolpropane di (meth) acrylate, trimethylolpropane tri (meth) acrylate, glycerin di (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate , Dipentaerythritol penta (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 2,2-bis (4-acryloxydiethoxyphenyl) propane, 2,2-bis (4- (meth) acryloxypolyethoxy) Phenyl) propane, 2-hydroxy-3- (meth) acryloyloxypropyl acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, diethylene glycol diglyci Di (meth) acrylate, 1,6-hexamethyldiglycidyl ether di (meth) acrylate, trimethylolpropane triglycidyl ether tri (meth) acrylate, bisphenol A diglycidyl ether di (meth) acrylate, diglycidyl phthalate diester (Meth) acrylate,
Examples include polyfunctional monomers such as glycerin polyglycidyl ether poly (meth) acrylate. In the present invention, it is necessary to use a compound represented by the above formula,
It is necessary to contain 50 to 100% by weight, preferably 70 to 100% by weight, based on the whole component (b). If the content is less than 50% by weight, the etching resistance is lowered, and the etching solution is soaked, which is not preferable. Specific examples of the compound represented by the formula include polypropylene glycol diacrylate and polypropylene glycol dimethacrylate, wherein n is 4 to 2.
0, preferably 4-17.

An appropriate amount of a monofunctional monomer may be used in combination with these polyfunctional monomers. Examples of such a monofunctional monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, 2
-Phenoxy-2-hydroxypropyl (meth) acrylate, 2- (meth) acryloyloxy-2-hydroxypropylphthalate, 3-chloro-2-hydroxypropyl (meth) acrylate, glycerin mono (meth) acrylate, 2- (meth) A) acryloyloxyethyl acid phosphate, phthalic acid derivative half (meth) acrylate, N-methylol (meth) acrylamide, nonylphenoxy polyethylene glycol acrylate, and the like.

The mixing ratio of (b) the ethylenically unsaturated compound is as follows: (a) a carboxyl group-containing polymer and (b)
5-90% by weight, preferably 20-80% by weight, particularly preferably 40% by weight, based on the total weight of the ethylenically unsaturated compound.
It is desirable to select from the range of ６０60% by weight. (B) An insufficient amount of the ethylenically unsaturated compound causes poor curing, reduced plasticity, and a delay in the development speed. (B) An excessive amount of the ethylenically unsaturated compound causes an increase in tackiness, cold flow, and peeling of the cured resist. It is not preferable because the speed is reduced.

(C) Examples of the lophine dimer include triphenylbiimidazoles, especially 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer,
2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) -4,5- (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,
5-diphenylimidazole dimer, 2- (o-methoxyphenyl) 4,5-diphenylimidazole dimer,
2,4- (p-methoxyphenyl) -5-phenylimidazole dimer, 2- (o-ethoxyphenyl) 4,5
-Diphenylimidazole dimer, 2,4-di (p-ethoxyphenyl) -5-phenylimidazole dimer and the like, among which 2- (o-chlorophenyl) -4,
5-Diphenylimidazole dimer is preferably used.

The compounding ratio of the (c) lophine dimer is 0.5 to 0.5 parts per 100 parts by weight of the total of (a) the carboxyl group-containing polymer and (b) the ethylenically unsaturated compound.
6.0 parts by weight, preferably 0.5 to 4.0 parts by weight, and more preferably 1.0 to 3.0 parts by weight. If the compounding ratio is less than 0.5 part by weight, insufficient curing of the resist or a decrease in sensitivity is caused, and if it exceeds 6.0 parts by weight, precipitation of development scum and a decrease in storage stability are not preferred. In particular, among (c) lophine dimers, triphenylbiimidazoles are used in an amount of 0.5 to 6.0 parts by weight based on 100 parts by weight of the total of (a) the carboxyl group-containing polymer and (b) the ethylenically unsaturated compound. Preferably 0.5
It is preferred that the content be contained in an amount of about 4.0 parts by weight.

(D) As the photopolymerization initiator, a compound represented by the above formula, N, N'-tetraalkyl-4,4 '
-Diaminobenzophenone, benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin phenyl ether, benzyl diphenyl disulfide, dibenzyl, diacetyl, anthraquinone, naphthoquinone, 3,3'-dimethyl-4-methoxybenzophenone Benzophenone, p, p'-bis (dimethylamino) benzophenone, p, p'-bis (diethylamino) benzophenone, pivaloin ethyl ether, 1,1-dichloroacetophenone, pt-butyldichloroacetophenone, 2-chloro Thioxanthone,
2-methylthioxanthone, 2,4-diethylthioxanthone, 2,2-diethoxyacetophenone, 2,2-
Dimethoxy-2-phenylacetophenone, 2,2-dichloro-4-phenoxyacetophenone, phenylglyoxylate, α-hydroxyisobutylphenone, dibezosparone, 1- (4-isopropylphenyl) -2
-Hydroxy-2-methyl-1-propanone, 2-methyl- [4- (methylthio) phenyl] -2-morpholino-1-propanone, tribromophenylsulfone, tribromomethylphenylsulfone, N-phenylglycine and the like are exemplified. These are used alone or in combination of two or more. In the present invention, it is preferable to contain at least the compound represented by the above formula.

The mixing ratio of the (d) photopolymerization initiator is as follows:
0.1 to 10 based on a total of 100 parts by weight of (a) the carboxyl group-containing polymer and (b) the ethylenically unsaturated compound.
Parts by weight, preferably 1.0 to 8.0 parts by weight, more preferably 2.0 to 5.0 parts by weight.
If the compounding ratio is less than 0.1 part by weight, the sensitivity is low and the practicality is poor. If the compounding ratio exceeds 10 parts by weight, the adhesiveness is reduced and the resist peels off during development, which is not preferable.

(E) Examples of leuco dyes include tris (4-dimethylaminophenyl) methane [leuco crystal violet] and tris (4-diethylamino-2).
-Methylphenyl) methane, leucomalachite green, leucoaniline, leucomethyl violet and the like. The mixing ratio of the (e) leuco dye is (a)
It is necessary to add 0.1 to 3.0 parts by weight, preferably 0.1 to 2.0 parts by weight, per 100 parts by weight of the total of the carboxyl group-containing polymer and (b) the ethylenically unsaturated compound. If the compounding ratio is less than 0.1 part by weight, the sensitivity is lowered, and the contrast after exposure is low. If the compounding ratio is more than 3.0 parts by weight, the adhesion is undesirably reduced.

The photosensitive resin composition (F) used in the present invention contains the above (a), (b), (c), (d) and (e) as essential components. Polymerization inhibitors, plasticizers,
Dyes other than leuco dyes (pigments, discoloring agents), adhesion promoters,
Additives such as antioxidants, solvents, surface tension modifiers, stabilizers, chain transfer agents, defoamers, flame retardants and the like can be added as appropriate.

For example, a thermal polymerization inhibitor is added for preventing thermal polymerization or polymerization with time of the photosensitive resin composition, and includes p-methoxyphenol, hydroquinone, t
-Butylcatechol, pyrogallol, 2-hydroxybenzophenone, 4-methoxy-2-hydroxybenzophenone, cuprous chloride, phenothiazine, chloranil, naphthylamine, β-naphthol, 2,6-di-t-butyl-p-cresol, nitrobenzene , Picric acid, p
-Toluidine and the like.

The plasticizer is added to control the physical properties of the film. Examples of the plasticizer include phthalic acid esters such as dibutyl phthalate, diheptyl phthalate, dioctyl phthalate and diallyl phthalate; triethylene glycol diacetate, tetraethylene glycol diacetate and the like. Glycol esters; phosphate esters such as tricresyl phosphate and triphenyl phosphate;
Amides such as p-toluenesulfonamide, benzenesulfonamide, Nn-butylacetamide; aliphatic dibasic acid esters such as diisobutyl adipate, dioctyl adipate, dimethyl sebacate, dioctyl azelate, dibutyl malate; citric acid Triethyl, tributyl citrate, glycerin triacetyl ester,
Glycols such as butyl laurate, dioctyl 4,5-diepoxycyclohexane-1,2-dicarboxylate, polyethylene glycol and polypropylene glycol,
Tri-n-butyl acetylcitrate, triethyl acetylcitrate and the like can be mentioned.

As the coloring matter, in addition to the leuco dye used in the photosensitive resin composition (a), for example, brilliant green, eosin, methyl violet, ethyl violet, ethylene violet, erythrosin B, methyl green, crystal violet, basic Fuchsin, phenolphthalein, 1,3-diphenyltriazine, alizarin red S, thymolphthalein, methyl violet 2B, quinaldine red, rose bengal, methanil yellow, thymol sulfophthalein, xylenol blue, methyl orange, orange IV, Diphenylthiocarbazone, 2,7-dichlorofluorescein, paramethyl red, congo red, benzopurpurine 4B, α-naphthyl red, nile blue A, phenacetaline, Rakite Green, Malachite Green Lake, Patent Blue, Parafuchsin, Oil Blue # 603, Victoria Pure Blue BOH,
Spiron Blue GN, Rhodamine 6G, Roseaniline and the like. Among them, malachite green and brilliant green are contained in an amount of 0.01 to 0.5% by weight, preferably 0.01 to 0.5% by weight.
Preferably, it is contained in an amount of up to 0.3% by weight.

The color-changing agent is added to the photosensitive resin composition so that a visible image can be given by exposure, and specific examples thereof include diphenylamine, dibenzylaniline, triphenylamine, diethylaniline, Diphenyl-p-phenylenediamine, p-toluidine,
4,4'-biphenyldiamine, o-chloroaniline,
And the like.

Examples of the adhesion promoter include benzimidazole, benzthiazole, benzoxozole, benztriazole, 2-mercaptobenzthiazole,
-Mercaptobenzimidazole, 4-benzotriazolecarboxylic acid, 5-benzotriazolecarboxylic acid,
Bis (N, N-2-ethylhexylaminomethyl)-
1,2,3-benzotriazole and the like.

The photosensitive resin composition (F) which can be used in the present invention is usually used as a photoresist film having a laminated structure. The photoresist film has at least one layer of the photosensitive resin composition (F) of the present invention, and a support film, a layer of the photosensitive resin composition (F), and a protective film as required. What did
For example, support film / photosensitive resin composition (F) (/
Protective film).

The support film used in the present invention has heat resistance and solvent resistance when forming the photosensitive resin composition (F) layer. Specific examples of the support film include, for example, a polyester film, a polyimide film, a polyvinyl alcohol film, and an aluminum foil, but the present invention is not limited to these examples. The thickness of the support film varies depending on the material of the film, and thus cannot be determined unconditionally. Usually, the thickness is appropriately adjusted depending on the mechanical strength of the film, but is usually about 3 to 50 μm. It is.

The thickness of the photosensitive resin composition (F) layer is as follows:
If it is too small, the coating becomes uneven when coating and drying, or pinholes are likely to occur.If it is too large, the exposure sensitivity decreases and the development speed decreases, Usually 5-300 μm, especially 7-
It is preferably 50 μm.

When the protective film used in the present invention is used in the form of a roll of a photoresist film, the photosensitive resin composition (F) layer having adhesiveness may be transferred to a support film, or the photosensitive resin composition may be used. It is used by being laminated on the photosensitive resin composition (F) layer for the purpose of preventing a wall or the like from adhering to the composition (F) layer. As such a protective film,
For example, polyester film, polyethylene film,
Examples thereof include a polypropylene film, a polyvinyl alcohol film, and a Teflon film, but the present invention is not limited to such examples. The thickness of the protective film is not particularly limited, and is usually 10 to
It may be 50 μm, especially 10 to 30 μm.

The dry film resist using the above-mentioned photosensitive resin composition (F) can be used, for example, by supporting the above-mentioned photosensitive resin composition (F) on a polyester film, a polypropylene film, a polystyrene film, a polyvinyl alcohol-based film or the like. After coating on the body film surface, if necessary, a protective film such as a polyethylene film is coated on the coated surface to produce a dry film resist. As a use other than the dry film resist, the photosensitive resin composition (F) of the present invention is directly applied onto a (42 alloy) substrate to be processed by a conventional method such as a dip coating method, a flow coating method, and a screen printing method. It is also possible to easily form a photosensitive layer having a thickness of 1 to 150 μm by coating. At the time of coating, methyl ethyl ketone, methyl cellosolve acetate, ethyl cellosolve acetate, cyclohexane, methyl cellosolve, methylene chloride, 1,1,1-
A solvent such as trichloroethane can be added.

In order to form an image with a dry film resist, the adhesive strength between the support film and the photosensitive resin composition (F) layer and the adhesive strength between the protective film and the photosensitive resin composition (F) layer are compared. Then, after peeling off the lower adhesive film, the photosensitive resin composition layer side is attached to a metal surface such as a copper surface of a copper-clad substrate, and then a pattern mask is adhered to the other film. Expose. When the photosensitive resin composition (F) does not have adhesiveness, the other film may be peeled off, and then the pattern mask may be brought into direct contact with the photosensitive resin composition (F) layer for exposure. When the coating is applied directly to the metal surface, a pattern mask is brought into contact with the coating surface directly or via a polyester film or the like, and exposed. Exposure is usually performed by UV irradiation,
At this time, high-pressure mercury lamp, ultra-high pressure mercury lamp, carbon arc lamp, xenon lamp, metal halide lamp,
A chemical lamp or the like is used. After irradiation with ultraviolet rays, heating can be performed as necessary to complete the curing.

After exposure, the film on the resist is peeled off and developed. Since the photosensitive resin composition (F) of the present invention is of a rare alkali developing type, development after exposure is carried out using an alkali such as sodium carbonate, potassium carbonate, or the like.
This is performed using a dilute aqueous solution of about 2% by weight. A surfactant, an antifoaming agent, a small amount of an organic solvent for accelerating development, and the like may be mixed in the alkaline aqueous solution.

In the present invention, after the development is completed,
Further, it is necessary to irradiate actinic rays. Examples of the actinic ray include an ultra-high pressure mercury lamp, a high pressure mercury lamp, a xenon lamp, and a metal halide. The irradiation amount of the actinic ray is preferably 0.5 to ³ J / cm ² ,
More preferably, it is set to ² J / cm ² . If the irradiation amount is less than 0.5 J / cm ² , the obtained effect tends to be insufficient, and if it exceeds 3 J / cm ² , the peelability of the resist tends to be significantly reduced. Further, for the purpose of assisting the effect of irradiating active light, it is preferable to heat a substrate having a metal surface containing iron before and after the step of irradiating active light.

Thereafter, etching is performed in a usual manner using an acidic etching solution such as an aqueous cupric chloride-hydrochloric acid solution or an aqueous ferric chloride-hydrochloric acid solution. Rarely, an ammonia-based alkali etching solution is also used. The plating method uses a degreasing agent,
After performing pretreatment using a plating pretreatment agent such as a soft etching agent, plating is performed using a plating solution.

After the etching step, the remaining cured resist is removed. Stripping and removal of the cured resist is performed using an alkali stripping solution composed of an aqueous alkali solution having a concentration of about 0.5 to 5% by weight such as sodium hydroxide or potassium hydroxide.

The method of forming a resist pattern according to the present invention comprises:
It contains (a) a carboxyl group-containing polymer, (b) an ethylenically unsaturated compound, (c) a lophine dimer, (d) a photopolymerization initiator, and (e) a leuco dye. Above all, the specific compound is added to the component (b) in an amount of 50 to
100% by weight, and the component (c) is added in an amount of 0.5 to 6.0 based on 100 parts by weight of the total of the components (a) and (b).
Using a photosensitive resin composition (F) containing 0.1 to 10 parts by weight of the component (d) and 0.1 to 3.0 parts by weight of the component (e), irradiation with actinic rays is performed after the development is completed. Therefore, even when a metal substrate other than copper such as 42 alloy or stainless steel is used, the adhesiveness between the substrate and the resist is excellent, there is no penetration into the conductor or the conductor is applied, and the resist pattern is formed in a short time and at a high yield. You can do it.

[0039]

The present invention will be described in more detail with reference to the following examples. Unless otherwise specified, “%” and “parts” are based on weight. [Preparation of photosensitive resin composition] As (a), using the following carboxyl group-containing polymer, dopes of photosensitive resin compositions (F-1) to (F-10) having compositions shown in Table 1 were prepared. did. (A) ・ Methyl methacrylate / methyl acrylate / 2-
Ethylhexyl acrylate / methacrylic acid (weight ratio: 5
8/10/10/22) and a 40% methyl ethyl ketone / 40% copolymer having a weight average molecular weight of 60000.
Isopropyl alcohol (weight ratio 50/50) solution
139.38 parts (solid content 55.75 parts)

[0040]

Table 1 Photosensitive resin (b) (c) (d) (e) Other compositions APG TMP-TA HABI BDK EAB-F LCV TBMPS MG (F) (%) (%) (%) (%) ( (%) (%) (%) (%) F-1 37.16 --- 2.0 4.0 0.06 0.7 0.3 0.03 F-2 18.58 18.58 2.0 4.0 0.06 0.7 0.3 0.03 F-3 27.87 9.29 2.0 4.0 0.06 0.7 0.3 0.03 F-4 14.86 22.30 2.0 4.0 0.06 0.7 0.3 0.03 F-5 32.16 --- 7.0 4.0 0.06 0.7 0.3 0.03 F-6 39.06 --- 0.1 4.0 0.06 0.7 0.3 0.03 F-7 30.16 --- 2.0 11.0 0.06 0.7 0.3 0.03 F-8 41.14 --- 2.0 0.05 0.03 0.7 0.3 0.03 F-9 33.86 --- 2.0 4.0 0.06 4.0 0.3 0.03 F-10 37.81 --- 2.0 4.0 0.06 0.05 0.3 0.03

Note) (a) All the carboxyl group-containing polymers have a blending amount of 55.75%. APG: polypropylene glycol diacrylate (n = 7) TMP-TA: trimethylolpropane triacrylate HABI: 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer BDK: benzyl dimethyl ketal EAB-F: N, N'-tetraethyl-4,4'-diaminobenzophenone LCV: leuco crystal violet TBMPS: tribromomethylphenylsulfone MG: malachite green (F-4) to (F-10) are photosensitive resin compositions defined in the present invention. is not.

Example 1 The photosensitive resin composition (F-1) was doped with a gap of 5
Using a mill applicator, coat on a 20 μm-thick polyester film, leave at room temperature for 1 minute and 30 seconds, and in an oven at 60 ° C., 90 ° C., and 110 ° C. for 3 minutes each.
After drying for 25 minutes, a dry film having a resist thickness of 25 μm was obtained (however, no protective film was provided). On the other hand, a substrate made of a nickel / iron alloy (42 alloy) containing 42% of nickel was treated at 50 ° C. with an alkaline degreasing agent (10% aqueous solution).
, Immersed in water for 2 minutes, further immersed in a 5% hydrochloric acid aqueous solution at room temperature for 20 seconds, washed with water, washed with purified water, and dried to use as a substrate. The substrate has a thickness of 0.15 mm, a width of 250 mm and a length of 300
mm substrate. The dry film was laminated on both surfaces of a substrate preheated to 60 ° C. in an oven at a laminating roll temperature of 100 ° C., a roll pressure of 3 kg / cm ² , and a laminating speed of 1.5 m / min.

Next, the value of a 21-step stofer step tablet (a negative film made so that the amount of light transmission decreases stepwise) with a 2 kW mercury short arc lamp (parallel light source) was 6 on the obtained substrate. Exposure was performed with the following exposure amount. After 15 minutes from the exposure, the polyester film is peeled off, and the unexposed portion is sprayed at 30 ° C. by spraying a 1% aqueous solution of sodium carbonate at a developing time twice as long as a break point (time for completely dissolving the unexposed portion). After dissolution and removal, a cured resin image was obtained.

Next, after irradiating an actinic ray with a light amount of 1.5 J / cm ² by an 8 kW high-pressure mercury lamp (conveyor type ultraviolet irradiation device), the substrate was heated at 50 ° C. and 45 B (Bohm).
For 8 minutes (spray pressure: 1.8 kg / cm ^{2 on} the upper side, 1.5 kg on the lower side)
/ Cm ² ). Next, the cured resin film used as a resist was peeled off by spraying with a 3% aqueous solution of sodium hydroxide at 50 ° C. for 50 seconds to form an image.

In the present invention, the following items were evaluated as follows. (Sensitivity) The photosensitivity of the photosensitive resin composition (F) was evaluated by measuring the exposure amount (mj / cm ² ) when the number of steps of the step tablet of the photocured film formed on the substrate was 6. .

(Adhesion) After lamination to a substrate, the line width is 10, 15, 20, 25, 30, 40, 45, 50 μm.
m, using a pattern mask (glass chrome dry plate: independent fine line), and developing in the same manner as above.
m) was examined.

(Antifoaming property) 1% sodium carbonate 500 ml
0.2m ^{2 of} unexposed resist (resist thickness 25μ)
m), and after stirring for one day, 100 ml of the sodium carbonate solution (unexposed resist solution) was transferred to a foaming bottle (bottle inner diameter: 9 cm), and the foaming bottle was placed in a thermostat water bath at 30 ° C. for 1 hour.
Left for hours. Thereafter, air was blown in at a rate of 1.0 l / min to foam the liquid. 10 minutes, 20 minutes, 30 minutes, 1 hour, 2 hours, and 6 hours after the start of the air supply, the height (cm) of the foam alone was measured to evaluate the foam suppressing property.

(Etching Resistance) Penetration into Conductor Line / Space = 400 μm / 300 μm After development,
The resist pattern was etched, and the substrate from which the resist was peeled was observed with a magnifying microscope to visually evaluate the degree of penetration of the etching solution. The evaluation criteria are as follows. ◎ ・ ・ ・ No permeation ○ ・ ・ ・ Permeate less than 2μm △ ・ ・ ・ Permeate less than 2-5μm × ・ ・ ・ Permeate more than 5μm

After development of a conductor line / line = 400 μm / 300 μm,
After the resist pattern was etched and the resist was peeled off, the base material was observed with a magnifying microscope, and the degree of chipping of the conductor was visually evaluated. The evaluation criteria are as follows.・ ・ ・: No chipping of conductor ○: Chipping less than 1/3 from end of conductor width △: Chipping of 1/3 or more from end of conductor width × ..No conductor

Examples 2 to 3 and Comparative Examples 1 to 7 In the same manner as in Example 1, except that the photosensitive resin composition (F) was changed as shown in Table 2, each performance was evaluated.

Comparative Example 8 The procedure of Example 1 was repeated, except that no irradiation with actinic rays was performed. Table 2 shows the evaluation results of the examples and the comparative examples.

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Table 2 Photosensitive Sensitivity adhesion foam Resistance etch resin ^{(mj / cm 2) (μm} ) 10 20 30 60 120 360 minutes after packaging composition (cm) Example 1 F-1 40 30 1 1 1 1 1 1 ◎ ◎ 〃 2 F-2 35 30 1 2 2 2 3 3 ◎ 〃 3 F-3 38 30 12 2 2 2 2 2 ◎ ◎ Comparative Example 1 F-4 40 35 1 2 3 3 5 8 ○ △ 〃 2 F-5 20 35 1 1 1 1 1 2 ○ ○ 〃 3 F-6 160 60 1 1 1 1 1 2 △ △ 〃 4 F-7 35 60 1 1 1 1 1 2 2 △ △ 〃 5F- 8 100 35 1 1 1 1 1 2 △ × ６ 6 F-9 16 60 1 1 1 1 1 1 △ × 〃 7 F-10 100 35 1 1 1 1 1 1 2 ○ △ ８ 8 F-1 40 30 1 1 1 1 1 1 ○ ○ In Comparative Example 2, scum was generated in the developing solution during development. The scum adheres to the substrate and causes a short circuit in etching or a disconnection in plating.

[0053]

According to the method of the present invention, even when a metal substrate other than copper, such as 42 alloy or stainless steel, is used, the adhesion between the substrate and the resist is excellent, the foaming resistance is low, and the migrating phenomenon such as penetration into the conductor and the conductor It is capable of forming a resist pattern in a short time and at a high yield, and has excellent etching resistance without chipping, and is useful for manufacturing a printed wiring board, manufacturing a lead frame, precision metal processing, and the like.

Claims (6)

[Claims] (1) a carboxyl group-containing polymer,
In a photosensitive resin composition comprising (b) an ethylenically unsaturated compound, (c) a olefin dimer, (d) a photopolymerization initiator, and (e) a leuco dye, the component (b) is represented by the following formula: The compound represented by the formula (5)
100% by weight, and the component (c) is added in an amount of 0.5 to 6.0 based on 100 parts by weight of the total of the components (a) and (b).
A photosensitive resin composition (F) layer containing 0.1 to 3.0 parts by weight of a component (d) and 0.1 to 3.0 parts by weight of a component (e) is formed on the surface of a metal substrate. Exposing, developing, and irradiating with an actinic ray after the development is completed. Embedded image (Here, R ₁ and R ₂ are an alkyl group having 1 to 3 carbon atoms or hydrogen, which may be the same or different from each other. N is an integer of 4 to 20.) 2. The method according to claim 1, wherein a dry film resist having at least one photosensitive resin composition (F) layer is used. 3. The method for forming a resist pattern according to claim 1, wherein (c) a triphenylbiimidazole is used as the lophine dimer. 4. Triphenylbiimidazole is added in an amount of 0.5 to 100 parts by weight of the total of the components (a) and (b).
4. The method according to claim 3, wherein the amount is from 6.0 to 6.0 parts by weight. 5. The method for forming a resist pattern according to claim 1, wherein (d) a compound represented by the following formula is used as the photopolymerization initiator. Embedded image (Here, R ₃ and R ₄ are hydrogen or an alkyl group, which may be the same or different from each other.) 6. The compound represented by the above formula is used in an amount of 0.1 to 1 based on 100 parts by weight of the total of the components (a) and (b).
6. The method according to claim 1, wherein 0 parts by weight are used.
The method for forming a resist pattern according to the above.