JPH0462375B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photomasking film, and more particularly to a photomasking film in which a diazo photosensitive layer is provided between a transparent plastic film support and a light-shielding mask layer, eliminating the need for opaque work. It is.

Conventionally, masking films have been used for photoengraving, drafting, or manufacturing printed wiring boards. One of the purposes of using such masking films is to produce various image masters by peeling off the desired portions from the film support. As the masking film, for example, one in which a red peelable light-shielding mask layer for blocking ultraviolet rays is provided on a plastic film support and a photosensitive material is coated thereon is known.

After imagewise exposing the masking film to ultraviolet light, the photosensitive material layer is developed with a developer, the photosensitive material layer in the non-exposed area is removed, and the underlying mask layer is chemically etched away with an etching solution. By doing this, a masking image is obtained. A photomasking film, which is a plastic film with a light-shielding peeling layer provided thereon, is very convenient for peeling off the desired image area and inserting another image such as a mesh pattern therein, so it has been widely used in recent years.

However, even if an attempt is made to peel off the mask layer 3b from the transparent base film 2 using the conventional masking film shown in FIG. 1 and print a transmitted light image of only the portion 3b, as shown in FIG. All I could get was a wide range of images. Therefore, as shown in Fig. 3, opaque ink 5 is applied to the etched portion 4.
After shielding the mask layer 3b from light, the mask layer 3b was peeled off so that the exposed light was transmitted through the peeled portion 3b as shown in FIG. However, when applying oil-based opaque ink on top of the mask layer,
The film of the mask layer melted, the etched image became difficult to read, and a bad odor was generated due to volatilization of the solvent. Furthermore, when water-based opaque ink is used, there are drawbacks such as it takes a long time to dry and the opaque film does not stand up well.

In order to improve the above-mentioned drawbacks, the inventors of the present invention have conducted various studies and found that by providing a diazo-sensitive light-shielding mask layer between the mask layer and the plastic film support, the opaque ink can be used without using the opaque ink. The present invention was completed based on the finding that a photomasking film having the same effect as that obtained by applying the above method can be obtained.

That is, the present invention is a photomasking film in which a diazo photosensitive layer, a peelable light-shielding mask layer, and a photoresist photosensitive material layer are sequentially provided on a plastic film support.

The present invention will be explained in more detail below.

Examples of the plastic film support used in the present invention include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyoxybenzoate, and polycarbonate films.

The diazo photosensitive layer provided on the plastic film support is formed by coating a diazo photosensitive liquid on the plastic film, in which a known diazo photosensitive dye and a coupler are dispersed or dissolved in a binder using water or an organic solvent as a solvent along with an auxiliary agent. obtained by doing.

For example, zinc chloride double salts or borofluoride salts of diazonium compounds such as P-N.N-diethylaminobenzenediazonium chloride, P-N.N-dimethylaminobenzenediazonium chloride, P-morpholinobenzenediazonium chloride, and m-oxyethyl Contains couplers such as phenol, resorcinol, phloroglucin, R acid, 2-oxynaphthalene carbonic acid, and oxyethylaniline, and further contains citric acid, tartaric acid, lactic acid, and aluminum sulfate as auxiliary agents. It is dissolved or dispersed in a binder comprising one or more components selected from butyrate, maleic acid-vinylpyrrolidone copolymer resin, vinyl acetate-acrylic resin copolymer, etc.

Next, a peelable light-shielding mask layer provided on the diazo photosensitive layer is prepared by dissolving a polymeric material such as polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, polystyrene, vinylidene chloride, acrylonitrile-butadiene copolymer, etc. in an organic solvent. , can be obtained by adding and mixing a colorant, and then coating and drying on the diazo photosensitive layer. Dyes and pigments can be used as coloring agents, but it is preferable to use light-shielding dyes that are soluble in organic solvents, such as CI Solvent Orange 6, CI Solvent Orange 40, CI
Solvent Red 83, CI Solvent Red 122, etc. are used. The photoresist photosensitive material layer provided on the peelable light-shielding mask layer is formed using a photosensitive material that becomes insoluble in water or organic solvents when irradiated with ultraviolet rays.

For example, photosensitive materials such as paraformaldehyde condensation products of P-diazodiphenylamine, 1,2-naphthoquinone azide derivatives and novolac resins, mixtures of diazidobenzalcyclohexane and cyclized rubber, polyvinyl cinnamate, and acrylate-polyvinyl alcohol. is used.

The photomasking film of the present invention can be suitably subjected to a matte finish for the purpose of preventing light reflection from the light shielding layer. For example, this can be done by sand matting the back side of the plastic film support or by applying a matting agent such as finely powdered silica.

An opaque diazo coloring layer can be created by simply etching the peelable light-shielding mask of the photomasking film of the present invention and subjecting the etched portion to an ammonia original image. Furthermore, since the diazo coloring layer is black or brown, there is a difference in color from the peelable light-shielding mask layer, so it is easy to find the area to be peeled. It should be noted that most of the usual diazo photosensitizers are yellow-brown in color, and when exposed to ultraviolet light, they decompose, lose their reactivity, and become transparent. For this reason, it is preferable to perform front exposure after peeling off the peelable light-shielding mask layer.

Furthermore, since opaque ink does not enter the etching grooves, the film stands up better, and the peelable light-shielding mask layer can be peeled off immediately after development. Since the opaque ink does not remain on the light-shielding mask layer, the hair removal area is visible. The back side of the plastic film support is sandmatted, a transparent plastic film is sandwiched between the PS plates, and when the printing plate is used, the blemish lines are no longer visible. As described above, the photomasking film of the present invention has many superior features compared to conventional photomasking films.

Next, the present invention will be specifically explained using examples.

Example 1 A diazo photosensitive solution having the following formulation was coated on one side of a polyethylene terephthalate film and dried to provide a diazo photosensitive layer.

4-(Tolylmercapto)-2,5-dimethoxybenzenediazonium BF ₄ 10 parts by weight Phloroglucin 25 parts by weight Aluminum sulfate 15 parts by weight Citric acid 10 parts by weight Thiourea 20 parts by weight Cellulose acetate butyrate 25 parts by weight Methyl cellosolve 700 parts by weight Next, a releasable light-shielding masking agent having the following formulation was applied onto the diazo photosensitive layer so that the film thickness after drying was 30 μm, and dried to provide a releasable light-shielding masking layer.

Vinyl chloride-vinyl acetate copolymer 5 parts by weight Vinylidene chloride resin 10 parts by weight Acrylonitrile-butadiene copolymer
5 parts by weight Methyl ethyl ketone 30 parts by weight Cyclohexanone 20 parts by weight Triol 20 parts by weight Oil-soluble dye 0.4 parts by weight (CI Solvent Red 122) Furthermore, a photoresist photosensitive solution having the following composition was applied on the peelable light-shielding mask layer and dried. Then, a photoresist photosensitive layer is provided.

A 33.6% aqueous solution of PVA with an average degree of polymerization of 500 255 parts Ethyl 2-hydroxyacrylate 213 parts Uranyl nitrate 3 parts A red photomasking film was obtained in the above manner. When the photomasking film of the present invention thus obtained is used, a masking film as shown in FIG. 4 can be easily obtained without using opaque ink.

That is, as shown in FIG. 5, when a document is placed and exposed to ultraviolet light, washed out with water and developed, the unexposed portion 13 is eluted and removed. Next, this unexposed portion is etched to obtain a photomasking film in which the releasable light-shielding mask layer has been etched. Next, this masking film is developed with ammonia to obtain a masking film in which the diazo photosensitive layer in the etched image area is black, as shown in FIG.

Next, as shown in FIG. 8, the central releasable light-shielding mask layer 20 is peeled off and the entire surface is exposed to light, thereby obtaining a photomasking film in which the etched portion is a black light-shielding mask layer, as shown in FIG.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a conventional masking film. FIG. 2 is a cross-sectional view showing a state where the mask layer 3b portion in FIG. 1 has been peeled off. FIG. 3 is a sectional view showing the masking film of FIG. 1 coated with opaque ink. FIG. 4 is a sectional view showing a state where the mask layer 3b portion in FIG. 3 has been peeled off.
FIG. 5 is a sectional view showing a transparent original placed on the photomasking film of the present invention and irradiated with ultraviolet rays. FIG. 6 is a sectional view showing a state in which the unexposed portion in FIG. 5 has been removed with water and further etched. FIG. 7 is a cross-sectional view showing a state in which the diazo photosensitive layer is developed and colored. FIG. 8 is a cross-sectional view showing the peeled state of the center mask layer 20 in FIG. 7. FIG. 9 is a sectional view showing a state in which a light-shielding diazo photosensitive layer is provided in the etching groove portion as shown in FIG. 1... Conventional photomask, 2... Plastic film, 3a, 3b... Light shielding layer, 4... Etching groove, 5... Opaque ink, 10... Original, 11... Image area, 12... Non-image Line part, 13...
...Unexposed area, 14... Exposed area (photoresist photosensitive layer), 15... Peelable light-shielding mask layer, 16...
Diazo photosensitive layer, 17...polyester film,
18...Etching groove, 19...Diazo coloring layer,
20...Central removable mask layer.

Claims (1)

[Scope of Claims] 1. A photomasking film comprising a diazo photosensitive layer, a peelable light-shielding mask layer, and a photoresist photosensitive material layer sequentially provided on a plastic film support. 2. The photomasking film according to claim 1, which uses a polyester film as the plastic film. 3. The photomasking film according to claim 1, wherein the releasable light-shielding mask layer is formed of a polymeric material containing a red or orange dye or pigment.