JPH0437984B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to novel photoresist compositions using phototropic materials.

More specifically, photosensitizers and diphenyl-β
- A novel photoresist composition containing a styrylmethane derivative, which is colored and cured by irradiation with ultraviolet rays or electron beams.

In recent years, photoresists have been widely used for various purposes.

This has the advantage of shortening the process and improving productivity due to the quick curing property of photosensitive resin, the advantage of saving resources and not causing environmental pollution due to being solvent-free, and the advantage of saving energy and forming precise patterns by curing with ultraviolet rays etc. This is due to the fact that it is extremely useful in practice compared to thermosetting resins.

Photoresists having such functions have recently come to be widely used in the processing of printed circuits and the advancement of integrated circuits such as ICs and LSIs, and even higher functionality has been required.

In particular, in the manufacture of printed circuit boards, one surface of a photopolymerizable film is adhered to the surface of a copper clad laminate, the other side of said photopolymerizable film is adhered to a membrane support, and then the photopolymerizable film is adhered to a membrane support in a predetermined pattern. Therefore, after exposing the photopolymerizable layer, (A) the support is removed and the unexposed area is washed away with a suitable organic solvent or alkaline aqueous solution to expose the copper layer; (B) the unexposed layer is exposed; A so-called "drum film" type photoresist, or a copper-clad laminate, in which the unexposed or exposed areas are removed along with the support by utilizing the difference in adhesion between the exposed areas and the support, or copper-clad laminates. Typical examples include "resist ink type" photoresists used in screen printing and the like.

These include video, stereo, gaming machines,
Applications are progressing to a wide range of industrial and consumer printed wiring boards, which are widely used in automobiles, computers, etc.

Photoresist compositions such as those described above are generally used in colored form in many cases from the viewpoint of workability, and in particular, photoresists that produce a clear difference in hue or density between the cured areas and unexposed areas after exposure to ultraviolet rays, etc. , is extremely convenient from the viewpoint of product management, such as controlling the exposure level, controlling the exposure position, and inspecting for scratches and disconnections when forming printed circuit boards.
No., USP 3121632 describes coloring systems based on leukotriphenylmethane dyes and sulfonyl halides, sulfenyl halides, or alkyl or aryl ketones; (2) JP-A-52-130701 describes aminotriarylmethane dyes and aminoxanthene dyes; or coloring system based on free base of aminoacridine dye and halide, (3) JP-A-55-13780
A color-forming system using a combination of a fluoran compound and a latent activator for a fluoran dye is proposed in the above publication.

However, even in these prior art,
The problems have not yet been completely resolved. For example, the compositions proposed in USP 3113024 and USP 3121632 are generally unstable, and only leuco crystal violet (blue-violet coloring system) has been applied to actual photoresist systems. First, this product also does not completely satisfy the needs of consumers because it lacks stability against heat (thermal coloring tendency) and has a natural coloring tendency during long-term storage of the resist.

In addition, in the system using the free base of the dye disclosed in JP-A-52-130701, the free base of the dye itself is a colored type, and there is a gap between the colored part and the uncolored part after exposure. It has not been commercialized because it is difficult to obtain a large contrast, and furthermore, the free base of such a dye is expensive and unstable.

Furthermore, in the system using fluoran compounds disclosed in JP-A No. 55-13780, compounds with sufficient coloring ability for practical use are limited to a limited number of compounds having a primary amino group in the molecule, and have not been put to practical use. 3-diethylamino-6-methoxy-7-amino-fluorane (red color).

As described above, the prior art does not completely satisfy the current needs for advanced photoresists for printed wiring boards; There is a strong need for photoresist compositions with excellent thermal and storage stability.

Particularly when working under yellow safety lights, the contrast can be clearly identified. A phototropic photoresist composition that develops a green to blue color is strongly desired.

In view of the above requirements, the present inventors have conducted intensive studies on photoresist materials that simultaneously change the polymerization degree of the resin and develop color upon irradiation with radiation, and have found that (a) in the presence of a photosensitizer; (b) A photosensitizer that generates radicals when irradiated with ultraviolet rays, and (c) General formula () (In the formula, R ₁ , R ₂ , and R ₃ represent an amino group, a substituted amino group, an alkyl group, an aryl group, an aralkyl group, an alkoxy group, a halogen atom, or a hydrogen atom, and at least one represents a substituted amino group. _Four ,
R ₅ , R ₆ and R ₇ represent an alkoxy group, an alkyl group, an aryl group, a halogen atom or a hydrogen atom.
However, if R ₁ and R ₂ are both dimethylamino groups and R ₄ and R ₅ are both hydrogen atoms, R ₃ , R ₆ ,
A new photoresist composition that essentially contains a diphenyl-β-styrylmethane derivative (in which one or more of R ₇ is substituted with a non-hydrogen atom) has the following properties: At the same time, it is colored deeply and provides a strong darkly colored cured resin layer; (2) pattern recognition based on the difference in color density between exposed and cured areas and unexposed areas can be performed extremely easily; and (3) storage stability. The present invention has been achieved by discovering that it has excellent thermal stability.

The photosensitive resin used in the composition of the present invention is a resin that can be polymerized by irradiation with electromagnetic waves or particle beams, such as ultraviolet rays, in the presence of a photosensitizer, such as (A) radical polymerization type photosensitive resin. Examples include resins, (B) addition polymerization type photosensitive resins, and the like.

Specifically, (A) radical polymerizable photosensitive resins include (1) ○ phthalic anhydride, isophthalic acid, terephthalic acid, adipic acid, sebacic acid, tetrahydrophthalic acid, methyltetrahydrophthalic acid, Polybasic acids such as hexahydrophthalic acid, methylhexahydrophthalic acid, hymic acid, trimellitic acid, pyromellitic acid, hectonic acid, etc. and ○roethylene glycol, propylene glycol, polyethylene glycol, polypropylene glycol, 1,3-butylene glycol, etc. Glycol, 1,4-butylene diglycol, 1,6-hexane diglycol, neopentyl glycol, glycerin, trimethylolethane, trimethylolpropane,
Pentaerythritol, dipentaerythritol, bisphenol A ethylene oxide addition,
Polyester (meth)acrylate resins obtained by esterification reaction with polyhydric glycols such as hydrogenated bisphenol A, polybutylene glycol, polycaprolactone, etc. and (meth)acrylic acid; A polyester obtained from a basic acid and the above-mentioned polyhydric glycol or a polyether such as polyethylene glycol, polypropylene glycol, polybutylene glycol, polycaprolactone, etc. and hatolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, etc. Isocyanates, diisocyanates such as hexamethylene diisocyanate, lysine diisocyanate, 4,4'-methylenebis(cyclohexyl isocyanate), hydrogenated tolylene diisocyanate, 1,3-(isocyanate methyl)cyclohexane, isophorone diisocyanate, trimethylhexamethylene diisocyanate, etc. A polyurethane (meth)acrylate resin obtained by the reaction of a monomer having a hydroxyl group and a (meth)acryloyl group, such as di-2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, etc.; )○Ibisphenol A diglycidyl ether, aliphatic glycidyl ether, novolac type epoxy resin, epoxidized polybutadiene, epoxidized oil and fat, fatty acid modified epoxy resin,
Epoxy (meth)acrylate resin obtained by reacting epoxy resin such as halogen-containing epoxy resin with ○ro(meth)acrylic acid, and others (4)○Ipolyacetal and ○ro 2-hydroxyethyl (meth)
Acrylate, 2-hydroxypropyl (meth)
Polyacetal (meth)acrylate resin obtained by the reaction of active hydrogen such as acrylate and (meth)acrylic acid with a monomer having a (meth)acryloyl group; ) Silicone (meth)acrylate resin with acryloyl groups introduced, (6)
○Imethyl (meth)acrylate, ethyl (meth)
Acrylate, butyl (meth)acrylate, isopropyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, (meth)acrylic acid,
α such as maleic acid, itaconic acid, fumaric acid, acrylamide, glycidyl (meth)acrylate, styrene, vinyltoluene, vinyl acetate, acrylonitrile, diethylaminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, morphonoethyl (meth)acrylate, etc. For example, for the glycidyl group of vinyl copolymer, (meth)acrylic acid For the hydroxyl groups of the vinyl copolymer, reacting monomers with carboxyl groups and (meth)acryloyl groups such as diisocyanate and 2hydroxyethyl (meth)acrylate, 2hydroxypropyl (meth)acrylate, etc. A monomer having a hydroxyl group and a (meth)acryloyl group is reacted, or for an acid anhydride group of a vinyl copolymer, a monomer having a hydroxyl group and a (meth)acryloyl group as described above is reacted. (meth)acrylate resin, (7) melamine (meth)acrylate resin, (8) polybutadiene (meth)acrylate resin, or (9) cyclopentadiene ( Examples include meth)acrylate resin.

(B) The addition polymerization type photosensitive resins include polythiol compounds such as pentaerythritol tetrakis (thioglycolate), trimethylolpropane tris (β-mercaptopropionate), and ethylene glycol dimercaptopropionate. The above radical polymerizable photosensitive resins,
Examples include combinations with unsaturated resins such as allyl terminal urethane resins, allyl terminal epoxy resins, allyl terminal epoxy resins, allyl terminal melamine resins, vinyl compounds, and diene compounds. These photosensitive resins may be used alone or in combination of two or more.

The photosensitizer used in the composition of the present invention may be, for example, a compound that generates radicals upon irradiation with ultraviolet rays, but it is required to have good radical generation efficiency. Examples of such photosensitizers include (1) benzoin-type photosensitizers such as benzoin, benzoin ethyl ale, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, and benzoin octyl ether; (2) 2 ,2-dimethoxy-
2-phenylacetophenone, 2,2-diethoxyacetophenone, P-phenoxy-2,2-dichloroacetophenone, P-t-butyl-2,
Acetophenone type photosensitizers such as 2,2-trichloroacetophenone, P-t-butyl-2,2-dichloroacetophenone, (3) 1-phenyl-1,
α-acyloquim ester type photosensitizers such as 2-propanedione-2-(o-ethoxycarbonyl)oxime and 1-phenyl-1,2-propanedione-2-(o-benzoyl)oxime, (4) Propiophenone type photosensitizers such as 2-hydroxy-2-methylpropiophenone and 4'-isopropyl-2-hydroxy-2-methylpropiophenone;
(5) Benzophenone type photosensitizers such as benzophenone, 4,4'-bisdiethylaminobenzophenone, chlorinated benzophenone, (6) 2-ethylanthraquinone, 2-t-butylanthraquinone, 2-amyl anthraquinone, 2- Anthraquinone type photosensitizers such as chloranthraquinone, (7) 2-chlorothioxanthone, 2-methylthioxanthone, 2
-thioxanthone type photosensitizers such as isopropylthioxanthone and 2,4-diisopropylthioxanthone; other (8) benzoate type photosensitizers such as methyl-orthobenzoyl benzoate; (9) p
Examples include benzaldehyde-based sensitizers such as -di-n-propylaminobenzaldehyde.
These photosensitizers may be used alone or in combination of two or more.

The diphenyl-β-styrylmethane derivative used in the present invention has the general formula () (In the formula, R ₁ , R ₂ , and R ₃ represent an amino group, a substituted amino group, an alkyl group, an aryl group, an aralkyl group, an alkoxy group, a halogen atom, or a hydrogen atom, and at least one represents a substituted amino group. _Four ,
R ₅ , R ₆ and R ₇ represent an alkoxy group, an alkyl group, an aryl group, a halogen atom or a hydrogen atom.
However, R ₁ and R ₂ are both dimethylamino groups, and R ₄ ,
When both R ₅ are hydrogen atoms, one or more of R ₃ , R ₆ , and R ₇ is substituted with a non-hydrogen atom. ), specifically, bis(4-dimethylaminophenyl)-β-
styrylmethane, bis(3-methyl-4-N-phenylaminophenyl)-β-styrylmethane,
Bis-(4-N-benzyl-N-methylaminophenyl)-β-styrylmethane, bis-(4-diethylaminophenyl)-β-styrylmethane, bis-(4-morpholinophenyl)-β-styryl Methane, bis-(4-ethylaminophenyl)-β-
Styrylmethane, bis-(3-methyl-4-diethylaminophenyl)-β-styrylmethane, bis-(2-methyl-4-dimethylaminophenyl)
-β-styrylmethane, bis(4-dimethylaminophenyl)-β-(4′-dimethylaminostyryl)methane, bis(4-dimethylaminophenyl)-β-(4′-methoxystyryl)-methane, Bis(4-diethylaminophenyl)-β-(3'-methoxy-4'-ethoxystyryl)methane, bis(4-dimethylaminophenyl)-β-(3',4',
5′-trimethoxystyryl)-methane, bis(4
-morpholinophenyl)-β-(3'-cyclohexyl-4'-methoxystyryl)methane, bis(4-
methoxyphenyl)-β-(4'-dimethylaminostyryl)-methane, bis(3-methyl-4-ethoxyphenyl)-β-(4'-diethylaminostyryl)-methane, 4-methylphenyl-4'- diethylaminophenyl-β-(3″-tert-butyl-
Examples include, but are not limited to, 4''-dimethylaminostyryl)-methane.

In order for the phototropic diphenyl-β-styrylmethane derivative used in the present invention to effectively develop color at the same time as the photoresist is cured during exposure, (1) it has a halogen atom in the molecule as a photosensitizer; When irradiated with ultraviolet rays, the polymerization or crosslinking reaction of the photosensitive resin proceeds, and halogen radicals are provided to convert diphenyl-β-
Halogen-containing photosensitizers that can rapidly and effectively carry out color-forming chemical reactions on styrylmethane derivatives, such as p-tert-butyl-2,2,
At least one of the photosensitizers includes 2-trichloroacetophenone, p-phenoxy-2,2-dichloroacetophenone, 4,4'-dichlorobenzophenone, 2-chloroanthraquinone, 2-chlorothioxanthone, etc. (2) Generate halogen free radicals using ultraviolet rays, etc. in general photosensitizers or the photosensitizers in item (1) above to effectively color diphenyl-β-styrylmethane derivatives. One example is a method in which a nonvolatile organic halogen compound that can be transferred to the mold is used in combination. Examples of nonvolatile organic halides used in method (2) include 1,1,1-tris(bromomethyl)
Propane, α, α, α′, α′tetrabromoxylene, α, α, α, α′, α′, α′-hexabromoxylene, α, α, α, α′, α′, α′-hexa Chloroxylene, hexachlorobenzene, hexabromobenzene, hexachlorocyclohexane, hexabromocyclohexane, hexachlorocyclopentadiene, hexabromodiphenyl ether, o-
Nitro-α,α,α-tribromoacetophenone, α,α,α-α′,α′,α′-hexabromo-p
-Diacetylbenzene, ω, ω, ω-tribromoxaldine, 2-ω, ω, ω-tribromomethyl-quinoline, hexabromodimethyl sulfoxide, pentabromodimethyl sulfoxide, hexabromodimethyl sulfone, 2 -Trichloromethyl-benzothiazolyl sulfone, tetrabromodimethyl sulfone, 2,4-dichlorophenyltrichloromethyl sulfone, trichloroacetic acid phenyl ester, trichloroacetic acid pentachlorophenyl ester, 4,4-dibromo-2,3-hexane dione, 2,2,4,4-tetrabromocyclobutanone, 2-chlorocyclohexanone, 2,
2,6,6-tetrabromocyclohexanone, 2
-iodo-1,3-cyclopentadione, 2,5
-dichloro-3,6-diethoxycarbonyl-hydroquinone, 2,5-dibromo-3,6-di-
n-butoxycarbonyl-hydroquinone, 2,
6-dichlorohydroquinone etc. are used, but
The invention is in no way limited to these exemplified compounds.

In addition, among these organic halides, compounds containing a large amount of halogen atoms, especially bromine, in the molecule also have a flame retardant effect, and photoresist compositions using such compounds have flame retardant properties. It is also industrially useful.

The amount of these organic halides to be used is determined experimentally depending on the generation of radicals by ultraviolet rays etc. and the coloring ability of the diphenyl-β-styrylmethane compound. It is used in a range of 0.1 to 10 parts by weight per part by weight.

The photoresist composition of the present invention is mainly used as a photoresist material for printed circuit boards in the following two ways.

(A) Use as a dry film resist After dissolving and diluting the photoresist composition of the present invention in a low boiling point solvent such as methyl ethyl ketone, it can be applied to various films such as polyamide, polyolefin, polyester, vinyl polymer, and cellulose ester (hereinafter referred to as "support material"). The film is coated with a continuous web coating machine, etc., and dried with hot air to form a thin resist layer, and then a protective film of polyolefin, polyester, etc. is layered on top using a pressure roller, etc. A so-called dry film resist with a sandwich structure is used.

In actual use, the protective film is removed and the resist film is superimposed on the clean copper surface of the copper-coated laminate and irradiated with ultraviolet rays to form a colored hardened resist film. Furthermore, if necessary, ultraviolet rays are irradiated through a mask that transmits light in desired pattern areas, and a colored image of diphenyl-β-styrylmethane is drawn on the copper plate at the same time as the resin hardens in the exposed areas, and in the unexposed areas. remains uncured and colorless or light-colored, and the exposed and unexposed areas can be easily recognized with the naked eye as a colored pattern.

(B) Use as a liquid resist After coating or printing a liquid photoresist made of the composition of the present invention on a material such as metal, plastics, paper, or glass by various methods, it is cured with ultraviolet rays and a colored image is formed. to form.

Alternatively, by press-bonding a film coated with the above composition using a roll coater, knife coater, flow coater, etc. to a copper-coated laminate, or by applying a roll coater, spray, flow coater, screen printing, gravure printing, etc. on a copper-coated laminate. It is coated by offset printing, dipping, etc., and is exposed to the entire surface or irradiated with ultraviolet rays through a mask that transmits light in the desired pattern, to form a colored cured coating on the entire surface or a colored image whose pattern can be recognized with the naked eye.

The composition of the present invention contains 0.05 to 20 parts by weight of a photosensitizer, preferably 0.05 to 20 parts by weight, based on 100 parts by weight of the photosensitive resin.
0.1 to 15 parts by weight, and the diphenyl-β-styrylmethane compound is 0.05 to 15 parts by weight, preferably 0.1
~5 parts by weight. When using a nonvolatile organic halide, it is generally used in an amount of 0.05 to 20 parts by weight.

The composition of the present invention may further contain (a) the following unsaturated compounds, such as (1) 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, cellosolve (meth)acrylate, if necessary. ) acrylate, methyl cellosolve (meth)acrylate, butyl cellosolve (meth)acrylate, carbitol (meth)acrylate, methyl carbitol (meth)acrylate, butyl carbitol (meth)acrylate, phenoxyethyl (meth)acrylate, benzyl (meth)acrylate , dicyclopentadienyl (meth)acrylate, dicyclopentadienyloxyethyl (meth)acrylate, vinyl acetate, N-vinylpyrrolidone, tetrahydrofurfuryl (meth)
Acrylate, nonylphenoxyethyl (meth)
Acrylate, 2-hydroxy-3-chloropropyl (meth)acrylate, 2-hydroxy-3
- Monofunctional (meth)acrylates such as phenoxypropyl (meth)acrylate, phenyl cellosolve (meth)acrylate, 2-hydroxyethyl (meth)acryloyl phosphate, (2) neopentyl glycol di(meth)acrylate,
1,6 hexane glycol di(meth)acrylate, 1,4-butylene glycol di(meth)acrylate, 1,3-butylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, polyethylene glycol, di(meth)acrylate , dipropylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, polybutylene glycol di(meth)acrylate, polycaprolactone di(meth)acrylate, bisphenol A
Dioxydiethylene glycol ether diacrylate, trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)
acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol hexa(meth)acrylate, etc.

Furthermore, the photoresist composition of the present invention may contain extender pigments with good ultraviolet transmittance, plasticizers, leveling agents, antifoaming agents, and thixotropic agents (thixotropant) in order to adjust its physical properties depending on the intended use. , chelating adhesive components such as phosphate esters to improve adhesion to the substrate, dyes to color the resist layer in advance, etc. can be added.

The novel photoresist composition of the present invention has better storage stability and heat stability (when heated) than photoresist compositions using known leucotriphenylmethane compounds, such as leuco crystal violet and leucomalachite green. It is a composition that is extremely excellent in terms of its ability to produce instantaneous color upon exposure to light.

In particular, when applied to dry film type photoresists, the heating conditions for removing volatile solvents such as methyl ethyl ketone and toluene can be raised to high temperatures, so the coating manufacturing operation speed can be greatly improved.

Also, compared to compositions using known leukotriarylmethane dyes and fluoran compounds,
It has excellent ability to produce ultraviolet light from blue to green, making it easy to distinguish colors under safety lights, and also has the effect of reducing the amount of expensive dyes used.

The photoresist composition of the present invention can be colored and polymerized by electromagnetic waves or particle beams.

Examples include light rays such as ultraviolet rays, near ultraviolet rays, gamma rays, and X-rays, and radiation having mass such as beta rays (electron beams) and alpha rays. Practically speaking, 50-400W/cm high-pressure mercury lamps, ultra-high-pressure mercury lamps, metal halide lamps,
Irradiation with ultraviolet rays or β-rays (electron beams) is often used, such as carbon arcs, fluorescent lamps with ultraviolet-emitting phosphors, argon glow lamps, solar lamps, electronic flash devices, photographic flash lamps, and the like.

The present invention will be explained below with reference to Examples and Comparative Examples.

Example 1 Polypropylene glycol (molecular weight 1000) 500
g, 116 g of 2-hydroxyethyl acrylate,
168 g of hexamethylene diisocyanate was placed in a flask equipped with a stirrer and a urethane reaction was carried out at 80°C to obtain urethane acrylate.

100 g of the urethane acrylate, 1.5 g of benzoin ethyl ether as a sensitizer and 1.5 g of p-phenoxy-2,2-dichloroacetophenone.
g, and further 0.5 g of bis-(4-dimethylaminophenyl)-β-(4'-methoxystyryl)methane as a dye precursor were mixed and dissolved to obtain a pale green transparent liquid resist composition.

The composition was screen printed on a copper-coated laminate to a thickness of 20μ to form a substantially colorless and transparent resist layer, and then irradiated with ultraviolet rays for 10 seconds using a 100W/cm high-pressure mercury lamp. The resist layer is completely cured and dark green (λ _nax 620mμ)
It was colored with a Macbeth colorimeter reflection density value of 1.03.

The cured film thus obtained has bendability,
The surface hardness and adhesion were good, and the colored image had excellent fastness to heat and light.

Example 2 Copolymer of 75% styrene and 25% methacrylic acid by weight 60 Pentaerythritol tetraacrylate 20 p-phenoxy-2,2-dichloroacetophenone 3 Bis-(4-dimethylaminophenyl)-β-
(4'-dimethylaminostyryl)-methane 0.5 bis-(4-dimethylaminophenyl)-β(3',
A composition having a weight composition of 4',5'-trimethoxystyryl)-methane 0.3 and methyl ethyl ketone 200 was applied to a 1 mil thick polyester film to give a dry thickness of 12 μm and air-dried. Covered with thick polyethylene film.

The polyethylene cover film of the dry film photoresist with the above-mentioned sanderch structure was removed, and the exposed surface of the photoresist was laminated on the cleaned copper surface of a copper-coated laminate (manufactured by Universal Oil Products), and pressed with a rubber cover roll to adhere tightly. Ta.

A high-contrast silver halide film in which the conductive pattern forms a transparent area on an opaque background is adhered to the top of the polyester film, and then
When UV rays were irradiated for 1 minute using a 250 W/cm ultra-high pressure mercury lamp, the UV-transmissive area was completely cured and turned into a deep blue-green color [Macbeth reflection density value 0.99]. The unexposed areas were not cured and remained colorless and transparent.
The unexposed areas were removed by a conventional method to obtain the desired blue-green cured colored pattern.

Example 3 Bisphenol type epoxy (trade name Epicote)
828 (manufactured by Yuka Ciel Epoxy Co., Ltd.), 72 g of acrylic acid and 0.5 g of triethylamine as an accelerator were added to carry out a ring-opening addition reaction of the epoxy groups to obtain epoxy acrylate.

80 g of the epoxy acrylate, 20 g of neopentyl glycol diacrylate, 2.0 g of benzoyl butyl ether as a sensitizer, 0.7 g of 2-tertbutylanthraquinone, and bis-(4-dimethylaminophenyl)-β-(3'-methyl- A liquid photoresist composition was obtained by mixing and dissolving 1.1 g of (4'-ethoxystyryl)-methane.

When the composition was applied to a thickness of 70μ on a bonded steel plate using a bar coater and irradiated with ultraviolet rays for 15 seconds using a 100W/cm metal halide lamp, it was completely cured to the inside, and the cured film was substantially the same as before exposure. Colored from colorless and transparent to deep green (λ _nax 629 mμ) [Macbeth reflection density value 1.05].

Comparative Example 1 Bis-(4-dimethylaminophenyl)-β-
The same procedure as Example 1 was carried out, except that the known leucomalachite green (4,4'-bis[dimethylamino]triphenylmethane) was used instead of (4'-methoxystyryl)-methane. A liquid resist composition was obtained.

Although the resist layer was treated and cured at the same time as Example-1, the resist layer was completely cured but was slightly colored (λ _nax
630mμ) [Macbeth reflection density value 0.58].

Example 4 Acrylic resin containing 50% toluene (trade name, Almatex L-1044 manufactured by Mitsui Toatsu Chemical Co., Ltd.)
100 parts by weight, (Product name: BP4EA manufactured by Kyoeisha Yushi) 50 parts by weight, 2-hydroxy-2-methylpropiophenone (Product name:
Darokyur 1173 (manufactured by Merck) bis(4-dimethylaminophenyl)-β-(4'-dimethylaminostyryl)-methane 1 part by weight, α, α, α, α′, α′,
Three parts by weight of α'-hexabromo-p-xylene and 50 g of toluene were mixed and dissolved in a room protected from ultraviolet rays to form a colorless and transparent solution.

This solution was applied onto a polyester film with a thickness of 25 μm using a bar coater so that the dry thickness was 20 μm, and then dried for 10 minutes in a dryer at 130° C. to evaporate the solvent. After drying, the resist layer was adhered to a 15 μm thick polyethylene film (protective layer) according to a conventional method to create a three-layered dry film resist. The photoresist layer was colorless and transparent. While the protective layer of the dry film was peeled off, it was heated and laminated onto the clean copper surface of a glass cloth epoxy copper-clad laminate, and then allowed to cool to room temperature. When a silver salt photomask was placed in close contact with the top and exposed to light using an ultra-high pressure mercury lamp (Oak Seisakusho 3KW x 1 lamp) under exposure conditions of 200mg x 15sec, the transparent part of the photomask was colored and hardened in deep blue [Macbeth reflection density]
0.89], the opaque areas were not hardened or colored, and the pattern recognition between the exposed and unexposed areas was extremely clear.

When this was spray-developed with 1,1,1-trichloroethane according to a conventional method, the unexposed areas were completely removed, the copper surface was exposed, and the blue pattern of the exposed areas remained.

Comparative Example 2 In Example-4, bis(4-dimethylaminophenyl)-β-(4'-dimethylaminostyryl)
- The same treatment was carried out except that leuco crystal violet (4,4',4''-tris[dimethylamino]-triphenylmethane) was used instead of methane. During the exposure process, the photoresist layer was colored blue and the contrast after exposure was not good.

Claims (1)

[Claims] 1 (a) photosensitive resin, (b) photosensitizer (c) general formula () (In the formula, R ₁ , R ₂ , and R ₃ represent an amino group, a substituted amino group, an alkyl group, an aryl group, an aralkyl group, an alkoxy group, a halogen atom, or a hydrogen atom, and at least one is a substituted amino group. _Four ,
R ₅ , R ₆ and R ₇ represent an alkoxy group, an alkyl group, an aryl group, a halogen atom or a hydrogen atom. However, R ₁ and R ₂ are both dimethylamino groups, and R ₄ ,
When R ₅ is a hydrogen atom, one or more of R ₃ , R ₆ , and R ₇ is substituted with a non-hydrogen atom. A photoresist composition.