JPS6355692B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in imaging materials. More specifically, a novel photosensitive material for image formation that can widen the development latitude to obtain a faithful image width (print width) by incorporating a specific compound in the mask layer. Regarding.

Conventionally, as an image forming material suitable for halftone images and line drawings, lithium film (a lithium-type silver halide photographic material developed with a lithium developer) using a silver halide emulsion has been mainly used. It's here. While ordinary silver halide emulsions place emphasis on gradation reproduction in halftone areas, this lithium film is intended to form an image consisting only of a transparent area and a black opaque area.

Therefore, it is necessary that the outline of the image be clear and that an accurate image width be obtained. By the way, when you actually create an image using lithium film, it is difficult to obtain these characteristics sufficiently for the following reasons. First, it is desirable for lithographic film to be clearly differentiated into transparent areas and blackened areas through development after reaching a critical light amount, but the characteristic curve changes from base density to high density areas. It has a certain degree of rise width. This appears as fringes around the image. Second, since the development of Lith film relies on contagious development using Lith developer, the image expands and grows with the development time, making it difficult to stop the development and making it easy for the image width to fluctuate.

Furthermore, in terms of industry demands regarding photosensitive materials for printing, there is an expectation that for work safety, there will be a shift to working in a bright room to the extent that PS plates are handled, and that non-silver halide photosensitive materials will be used. Solving the above problems is highly desirable from the standpoint of effectively utilizing limited resources.

An image forming method using a non-silver salt photosensitive material includes, for example, having a mask layer on a support that absorbs visible light or an exposure light source when used as a manuscript;
On this layer, when exposed, a change in solubility in a developing solution occurs between the unexposed area and the exposed area, and one of the materials has a photoresist layer that remains after development. A portion where the photoresist layer is eluted by treatment with a solvent that does not dissolve the remaining hardened (resist) portion of the photoresist layer and can dissolve the mask layer while developing the photoresist layer or after developing the photoresist layer. There is a method of dissolving and removing the mask layer to form an image.

What is important in the above-mentioned image forming method is that the outline of the image obtained by the development process after image exposure is clear and that the width of the image is faithfully reproduced. For example, as shown in JP-A-52-89916, when the mask layer on the support is made of a polymer and carbon black, the polymer inherently dissolves in the developer during the development process. When the development time and development temperature change, the amount of dissolved polymer also changes sensitively, making it difficult to faithfully reproduce the image width.
That is, the development latitude is narrow.

The present inventors have conducted repeated research into developing an image forming material with a wide development latitude in an image forming material having a mask layer on a support and a photoresist layer on the layer. colorant,
It was discovered that the intended purpose could be achieved by containing a developer-soluble polymer and an emulsion polymer, and the present invention was completed.

In other words, by containing an emulsion polymer in addition to a colorant and a developer-soluble polymer in the mask layer, the proportion of the developer-soluble polymer in the mask layer can be relatively reduced while maintaining film-forming properties. As a result, the change in the amount of dissolution of the mask layer due to changes in development time and temperature can be made much slower than that of conventional mask layers that do not contain emulsion polymers. In other words, the development latitude for obtaining a faithful image width can be widened.

The present invention will be explained in detail below.

The support in the image forming material of the present invention is a self-supporting material, and by having self-supporting property, it is possible to support a covering layer such as a mask layer provided on the support without expanding or contracting. means. Examples include glass plates, plastic films, and paper, but from the viewpoint of handling during work, self-supporting and flexible materials such as plastic films and paper are preferred. Examples include polyethylene terephthalate, polycarbonate, polyvinyl chloride, polystyrene, cellulose triacetate, baryta paper, resin coated paper, and the like. Further, the material used as the support may be colored for a certain purpose.

In the present invention, a mask layer is provided on a support, but the support may be subjected to flame treatment or corona discharge treatment, or both. A subbing layer may be provided in between. The subbing layer is formed by coating a solution of a suitable polymer solution composition onto the support. Examples of materials used for the undercoat layer include:
Vinylidene chloride-acrylonitrile-itaconic acid copolymers, polymers or copolymers of glycidyl acrylate or glycidyl methacrylate, ester polymers of acrylic acid or methacrylic acid amide derivatives and acrylic acid or methacrylic acid, vinyl chloride-vinyl acetate-maleic anhydride copolymers, fatty acid vinyl Examples include ester copolymers of phthalic acid or isophthalic acid and glycols, styrene copolymers, acrylonitrile copolymers, and gelatin is also effective as a subbing material. As for the method for providing the subbing layer, there are well-known techniques in the photographic manufacturing industry, and these can be applied.
Generally, the above-mentioned polymer is made into a solution with water or an organic solvent, and this solution is applied onto a support by a coating method such as roll coating, air knife coating, or spray coating.

A mask layer containing a colorant, a developer-soluble polymer and an emulsion polymer is provided on the above-mentioned support. The coloring agent is contained in the mask layer in order to determine whether an image has been formed or to give density to the image area so that it can be printed onto a printing plate. Alternatively, it is preferable to set the value to be 1.0 or more in the visible light region.

The coloring agent used in the present invention is a dye or a pigment, and the color tone of the coloring agent is not particularly limited. Since it is necessary to have absorption in the range of at least 300 to 400 nm or 400 to 600 nm.

Examples of colorants used in the present invention include carbon black (including prepolymerized or grafted carbon black), graphite, iron black, aniline black, cyanine black, cobalt purple, manganese purple, fast violet B, methyl Examples include violet lake, dioxane violet, ultramarine blue, navy blue, cobalt blue, cerulean blue, alkali blue lake, phthalocyanine blue, indigo aluminum powder, copper powder, and the like. Other known pigments and dyes can be selected as appropriate. These colorants may be used alone, or two or more types may be used.

The mask layer of the present invention contains a developer-soluble polymer so that the photoresist eluted portion is removed during development. As for the developing solution for removing the unexposed areas, it is not preferable to use an organic solvent from the viewpoint of work safety and pollution, and it is practically preferable to use an aqueous developing solution such as an alkali, and it is more preferable to use water. . The developer soluble polymer used in the present invention specifically means a polymer soluble in water or an aqueous developer, such as polyvinyl alcohol or its derivatives, polyvinylpyrrolidone or its derivatives, gum arabic, gelatin, carboxymethyl cellulose. , polyethylene oxide, hydroxypropyl methylcellulose, methylcellulose, alginic acid, polyacrylic acid or a copolymer thereof, polyacrylate or a copolymer thereof, polymethacrylic acid or a copolymer thereof, and the like. These developer-soluble polymers may be used alone in the mask layer, or two or more types may be used simultaneously.

The mask layer of the present invention contains an emulsion polymer for the purpose of widening the development latitude. Emulsions are small particles of water-insoluble polymers dispersed in water.
generally well known. Therefore, the emulsion polymer in the present invention means a polymer that exists in the form of an emulsion, and the emulsion polymer useful in the present invention is limited to the type of polymer, as long as it is not soluble in the developer. Not done. Further, these emulsion polymers may be used alone, or two or more types may be used in combination. Typical examples of the emulsion polymer used in the present invention include polyacrylic acid ester or copolymer thereof, polyacrylonitrile or copolymer thereof, polystyrene or copolymer thereof, polyethylene or copolymer thereof, polyvinyl chloride or copolymer thereof, polyvinylidene chloride. or copolymers thereof, polyvinyl acetate or copolymers thereof, resol resins or copolymers thereof, polymethyl methacrylate or copolymers thereof, polybutadiene or copolymers thereof, and other emulsion polymers. Particularly preferred are polyacrylic esters or copolymers thereof, polyethylene or copolymers thereof, polyvinylidene chloride or copolymers thereof, and polyvinyl acetate or copolymers thereof.

The mask layer of the present invention is prepared by mixing an aqueous solution, an aqueous solution, an organic solvent solution, or a mixed solution of an emulsion polymer and a developer-soluble polymer, and further dispersing a colorant uniformly as a coating solution. Conventional coating techniques such as roll coating, air knife coating, slide hopper coating,
It is formed by applying it onto the above-mentioned support by extruder coating, doctor blade coating, etc. and drying it.

As mentioned above, the mask layer of the present invention contains a colorant, a developer-soluble polymer, and an emulsion polymer. The colorant in the mask layer is 5 to 60% by weight, preferably 10 to 50% by weight.
It is preferable that the content is % by weight. The developer soluble polymer is contained in the mask layer in an amount of 5 to 60% by weight, preferably 10% by weight.
It is preferable that the content be ~50% by weight; if it is less than 5% by weight, it will be difficult to remove the photoresist elution area, and if it is more than 60% by weight, the development latitude will be narrowed and the intended purpose of the present invention will not be met. Contrary. Furthermore, the emulsion polymer is present in the mask layer at 20~
The content is preferably 80% by weight, preferably 30 to 70% by weight; if it is more than 80% by weight, it will be difficult to remove the photoresist elution area, and if it is less than 20% by weight, the latitude of development will be narrowed. , which is contrary to the intended purpose of the present invention. The mask layer of the present invention has a concentration of
In order to obtain a value of 1.0 or more, a thickness of 0.5 μ or more is required, and a thickness of about 0.5 to 8 μ is sufficient.
If the mask layer becomes too thick, side etching of the mask layer occurs during removal by development, making it impossible to faithfully reproduce the image width. Note that the mask layer of the present invention may contain a known photosensitive substance in order to further widen the development latitude.

A photoresist layer is provided on the mask layer of the present invention thus provided. "Photoresist layer" is a term already known in the photographic manufacturing industry, which consists of a photosensitive film-forming material whose exposed and unexposed areas have different properties depending on the exposure, e.g. Either one can be removed from the layer with a suitable solvent, and the remaining one is resistive (insoluble) in that solvent. Examples of such photoresist layers include silver halide photographic emulsion layers and photopolymer layers.
There are "negative types" in which unexposed areas are removed and "positive types" in which exposed areas are removed, and commercially available products are also available. Examples of commercially available products include photopolymer “AZ-1350” manufactured by Shippley, USA, photopolymer “KPR” manufactured by Eastman Kodatsu Co., Ltd., photopolymer “TPR” manufactured by Tokyo Ohka Co., Ltd., and photopolymer “TPR” manufactured by Fuji Pharmaceutical Co., Ltd.
"EPPR" manufactured by Asahi Kasei Co., Ltd., and "Shear-in-coat photosensitive liquid" manufactured by Asahi Kasei Corporation.These materials can be used as the photoresist layer of the present invention, but from the viewpoint of work safety and pollution, it is necessary to remove the photoresist layer. Preferably, the liquid is water or water-based. Techniques for forming resist images on these silver halide photographic emulsion layers and photopolymer layers are conventionally known and can be utilized in the present invention.

The image-forming material according to the present invention prepared in this way is subjected to image exposure from the photoresist layer side, then the photoresist layer is developed, and the mask layer in the area where the photoresist layer has been removed is further developed and removed. This creates a negative or positive image.

Various light sources are used for image exposure, such as a high-pressure mercury lamp, a metal halide lamp, a tungsten lamp, a fluorescent lamp for diazo-sensitive materials, an iodine lamp, a xenon lamp, and a laser light source. The exposure method may be contact exposure overlapping the original, enlargement exposure, or reflection exposure. In the exposed image forming material according to the present invention, for example, in the case of a photopolymer layer, the resist portion does not dissolve;
By developing and removing the non-resist portion with a processing liquid that dissolves the non-resist portion, and further developing and removing the non-resist portion with a processing liquid that dissolves the mask layer in the non-resist portion and does not dissolve the resist portion of the photopolymer layer, the desired image is formed. form. Practically speaking, it is more preferable that the same processing solution be used to develop and remove the non-resist portion and the mask layer.

Examples of the present invention will be described below, but the embodiments of the present invention are not limited thereto. In addition, unless otherwise specified in the examples, "parts" indicate the proportion of ingredients.
represents "parts by weight".

Example 1 A coating solution having the following composition was applied onto a cellulose triacetate film provided with an undercoat layer and dried to form a mask layer with a thickness of approximately 2 μm.

[Coating liquid] Primal B-15 [manufactured by Nippon Acrylic Co., Ltd., acrylic acid ester emulsion] 4.7 parts Styrene-methacrylic acid copolymer (styrene/
Methacrylic acid = 6/4) 2.4 parts Aniline black 2.9 parts Acetone 30 parts Water 70 parts On top of this mask layer, apply a positive photoresist, AZ-1350 (manufactured by Shipley, USA), and dry to a thickness of approx. A 2μ photoresist layer was applied.

The image forming material according to the present invention thus prepared was superimposed on a manuscript, exposed for 15 seconds using a bright room printer (manufactured by Ueno Chemical Co., Ltd., UP-6, 3KW, metal halide lamp), and then heated at 25°C. When developed with alkaline developer MF-312 (Developer manufactured by Shipprey) and then washed off the exposed areas with tap water at 25℃, a faithfully reproduced positive image was obtained within a developing time range of 30 to 50 seconds. It was done.

Comparative Example 1 A comparative image forming material was prepared in the same manner as in Example 1 except that a mask layer was provided using a coating liquid having the following composition instead of the [coating liquid] used for the mask layer in Example 1. When exposure, development, and water washing were carried out in the same manner as in Example 1, a faithfully reproduced positive image could only be obtained when the development time was in the range of 40 to 45 seconds.

Styrene-methacrylic acid copolymer (styrene/
Methacrylic acid = 3/7) 7.1 parts Aniline black 2.9 parts Acetone 50 parts Water 50 parts Example 2 [Coating liquid] consisting of the following composition was prepared,
A mask layer having a thickness of approximately 4 μm was provided by coating and drying on a polyethylene terephthalate film provided with an undercoat layer.

[Coating liquid] Cevian A-535 [manufactured by Daicel Chemical Co., Ltd., acrylic acid ester emulsion] 5.2 parts Dyulymar-AC-10L [manufactured by Nippon Pure Chemical Industries, Ltd., polyacrylic acid] 3.2 parts Carbon Black #50 [ Manufactured by Mitsubishi Chemical Industries, Ltd.
1.6 parts Water 100 parts On top of this mask layer, a photopolymerizable negative type shear-in coat photosensitive liquid (manufactured by Asahi Kasei Corporation) was applied and dried to provide a photoresist layer with a thickness of about 4 μm. The image forming material according to the present invention thus prepared was superimposed on the original and exposed for 60 seconds using a bright room printer (same as in Example 1). When developed with a 20x PS plate developer produced by Kogyo Co., Ltd. and then washed with tap water at 25°C to remove the unexposed areas, a negative with faithful reproduction was obtained within the developing time range of 25 to 40 seconds. Image obtained.

Comparative Example 2 A comparative image forming material was prepared in the same manner as in Example 2, except that a mask layer was provided using a coating liquid with the following composition instead of the [coating liquid] used for the mask layer in Example 2. However, when exposure, development, and water washing were carried out in the same manner as in Example 2, the development time was 30~30 minutes.
A faithfully reproduced negative image could only be obtained over a 35 second period.

Jurimer AC-10L 8.4 parts Carbon Black #50 1.6 parts Water 100 parts Example 3 A [coating solution] consisting of the following composition was prepared and applied onto a polyethylene terephthalate film provided with an undercoat layer, dried and thickened. A mask layer of approximately 5 μm was provided.

[Coating liquid] Saran Latex L-405 [manufactured by Asahi Dow Co., Ltd., vinylidene chloride emulsion] 3.1 parts Jurimer-AT-210 [manufactured by Nippon Pure Chemical Industries, Ltd., polyacrylic acid ester copolymer] 3.9 parts HV Polymer D-100 [manufactured by Denki Kagaku Kogyo Co., Ltd.] 1.1 parts Graphite 0.9 parts Water 100 parts On top of this mask layer, prepare a coating solution with the following composition and apply a negative photoresist layer with a thickness of about 3μ. Established.

trimethylolpropane triacrylate
4.4 parts Miherazketone 1.0 part Styrene-methacrylic acid copolymer (styrene/methacrylic acid copolymer
Methacrylic acid = 1/1) 4.6 parts Methyl cellosolve acetate 100 parts The thus prepared image forming material according to the present invention was exposed to light, developed, and washed with water in the same manner as in Example 2, and the development time was A faithfully reproduced negative image was obtained in the range of 45 to 60 seconds.

Comparative Example 3 A comparative image forming material was prepared in the same manner as in Example 3 except that a mask layer was formed using a coating liquid having the following composition instead of the [coating liquid] used for the mask layer in Example 3. When exposure, development, and washing and removal were carried out in the same manner as in Example 2, a faithfully reproduced negative image could only be obtained when the development time was in the range of 55 to 60 seconds.

Jurimer AT-210 7.0 parts HV Polymer D-100 1.1 parts Graphite 0.9 parts Water 100 parts Example 4 [Coating solution] consisting of the following composition was prepared and applied to polyethylene laminated baryta paper treated with corona discharge. , and dried to provide a mask layer with a thickness of about 1 μm.

[Coating liquid] Polyemal PH-81 [manufactured by Asahi Kagakusei Co., Ltd., synthetic resin emulsion] 2.5 parts Polysol L-300 [manufactured by Showa Kobunshi Co., Ltd., ethylene-vinyl acetate modified resin emulsion] 2.0 parts Methyl methacrylate-methacrylic Acid copolymer [methyl methacrylate/methacrylic acid = 1/
9) 3.2 parts Phthalocyanine blue 2.3 parts Methanol 20 parts Water 80 parts A coating solution having the composition shown below was prepared on top of this mask layer, and was applied and dried to provide a negative photoresist layer with a thickness of about 3 μm.

Diazo resin (manufactured by Fairmount, Diazo No.
4) 0.9 parts Polyvinylpyrrolidone K=90 (manufactured by General Aniline Co., Ltd.) 2.8 parts Hitech E-5403B [manufactured by Toho Chemical Co., Ltd., polyethylene emulsion] 6.3 parts) Water 100 parts Image according to the present invention created in this way After exposing the forming material for 40 seconds using a bright room printer (same as in Example 1), the unexposed areas were removed by gently rubbing it with a sponge while immersed in tap water at 25°C. Negative images with good reproduction were obtained within the range.

Comparative Example 4 A comparative image forming material was prepared in the same manner as in Example 4, except that a mask layer was formed using a coating liquid having the following composition instead of the [coating liquid] used for the mask layer in Example 4. When exposure, development and removal were carried out in the same manner as in Example 4, a negative image with good reproducibility was obtained only when the immersion time was in the range of 30 to 35 seconds.

Methyl methacrylate-methacrylic acid copolymer (methyl methacrylate/methacrylic acid = 1/
9) 7.7 parts Phthalocyanine Blue 2.3 parts Methanol 50 parts Water 50 parts Comparative Example 5 A mask layer was provided with a coating liquid having the following composition instead of the [coating liquid] used for the mask layer in Example 1, and the other conditions were as in Example 1. A comparative image forming material was prepared in the same manner as in Example 1, and exposed, developed, and washed away with water in the same manner as in Example 1, but no development was possible.

Primal B-15 7.1 parts Aniline black 2.9 parts 50 parts of acetone 50 parts water

Claims (1)

[Claims] 1. An image forming material having a mask layer on a support and a photoresist layer on the mask layer, characterized in that the mask layer contains a colorant, a developer-soluble polymer, and an emulsion polymer. image-forming materials.