JPH01185550A - Photosensitive composition - Google Patents

Abstract

PURPOSE:To make possible to develop the title composition with water or a hot water, and to obviate the coloring of the photosensitive composition caused by coloring due to a photosensitive component and an image forming reaction by composing the photosensitive composition of a water soluble polymer having at least one kind of the groups comprising specified stylbazolium and stylquinolium groups, and a synthetic resin, etc. CONSTITUTION:The photosensitive composition is composed of the water soluble polymer which has at least one kind of a group capable of supplying a photosensitive component selected from the groups comprising the stylbazolium and stylquinolium groups shown by formulas I and II, and is capable of developing with the water or the hot water, and the synthetic resin emulsion and if necessary, a coloring agent. In formulas I and II, R1 and R2 are each hydrogen atom or alkyl group, Y<-> is a conjugated basic ion of an acid, * is a bonding position to the water soluble polymer through a linking group. Thus, the photosensitive composition is made possible to develop with the water or the hot water, and the coloring of the composition caused by the coloring with the photosensitive component or its decomposed material and the image forming reaction, is obviated.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a positive-working photosensitive composition. More specifically, it relates to a positive-working photosensitive composition used to prepare a positive-working image-forming material by coating on a support, and is mainly used for printing plate-making materials, copying materials, and the like.

[Prior art and problems to be solved by the invention] Photosensitive compositions used in conventional positive image forming materials include (1) a composition comprising an O-quinonediazide compound and a novolak resin; It is a composition consisting of alkali-soluble resins such as 0-quinonediazide, which utilizes the phenomenon that an 0-quinonediazide compound changes into an alkali-soluble substance upon irradiation with light (for example, JP-A-50-1258).
No. 06, JP-A No. 61-5251, etc.).

(2) Composition consisting of photosensitive diazonium salt and water-soluble resin A composition consisting of photosensitive diazonium salt and water-soluble resin such as polyvinyl alcohol, diacetone acrylamide-acrylamide copolymer, etc. This method utilizes the phenomenon in which a water-soluble resin undergoes a coupling reaction in an alkaline atmosphere and becomes water-insoluble (for example, JP-A-56-101141, JP-A-56-1011).
No. 44, JP-A-57-72140, JP-A-57-19
1632 etc.).

However, these conventional photosensitive compositions have the following problems. In other words, ■(1).

In both cases (2), an alkaline solution is used for development, which may cause safety problems in the development work and pollution problems in wastewater treatment. For (2), development treatment using ammonia vapor is also possible, but the strong ammonia odor significantly worsens the working environment.

(2) The image formed in (1) retains the color of the O-quinonediazide compound or its decomposed product, and (2) has a unique color developed by the coupling reaction. For this reason, (1),
In both cases (2), it is difficult to obtain a colored image in any desired color even if a coloring agent is added.

An object of the present invention is to provide a positive-working photosensitive composition for producing a positive-working image-forming material, which can be developed with water or hot water and is free from coloration caused by photosensitive components or their decomposition products, and color development caused by image-forming reactions. be.

(Means for Solving the Problems) As a result of intensive research into a new positive-working photosensitive composition that can be developed with water or warm water, the present inventors found that Medium R1 and ceramic are
Each independently represents a hydrogen atom or an alkyl group, Y- represents a conjugated basic ion of an acid, and * represents a bonding position that is bonded to a water-soluble polymer via a linking group. ) A photosensitive layer formed on a support with a composition consisting of a synthetic resin emulsion and a water-soluble polymer having at least one selected from the stilbazolium group and stilquinolium group as a photosensitive component addition group is a positive manuscript. We discovered a phenomenon in which a positive image can be obtained by exposing the material to light, immersing it in water, and rubbing it with a sponge. Further, the obtained image was completely free from coloring due to photosensitive components and coloring due to image forming reaction. The mechanism of this phenomenon is thought to be as follows.

0 exposure area When exposed to actinic light, the photosensitive component of a water-soluble polymer having a stilbazolium group or stilquinolium group as a photosensitive component addition group in the photosensitive layer undergoes a photodimerization reaction and becomes water-insolubilized. By immersing it in water or hot water, the water-insoluble water-soluble polymer easily swells, softening the photosensitive layer in this area. It also reduces the adhesion to the support. Therefore, this portion can be easily removed from the support by rubbing with a sponge or the like.

0 When the unexposed area is immersed in water or hot water, most of the water-soluble polymer having a stilbazolium group or stilquinolium group as a photosensitive component addition group in the photosensitive layer is eluted into the water or hot water.

However, there is no change in the photosensitive layer, such as swelling or softening, and the adhesion to the support remains unchanged. Therefore, even if rubbed with a sponge, it will not be removed from the support, and an image will be formed with a component mainly composed of a synthetic resin emulsion. Further, this image has no special coloring and is either colorless or the color of the added colorant is unchanged.

The present invention relates to a positive photosensitive composition using overprint dyeing.

Hereinafter, the present invention will be explained in detail based on its embodiments.

The water-soluble polymer having a photosensitive component addition group used in the photosensitive composition of the present invention is as follows:
I) (However, in the above formula, R1 and R each independently represent a hydrogen atom or an alkyl group, Y- is a conjugated basic ion of an acid, and * is a bonding position that is bonded to a water-soluble polymer via a linking group. ) is a water-soluble polymer having at least one selected from the stilbazolium group and the stilquinolium group as a photosensitive component addition group;
Numerous examples include polyvinyl alcohol, polyacrylamide, polyvinylpyrrolidone, gelatin, casein, egg white, gum arabic, and mixtures thereof. In addition, the addition rate of the photosensitive component addition group to these water-soluble polymers is preferably 0.2 to 5.0 mol%; if it is less than this, sufficient water insolubilization will not occur, and if it is more than this, it will be difficult to combine with the synthetic resin emulsion. Miscibility may deteriorate. These are JP 56-5761, JP 5B-5762, JP 56-11906, and JP 62-23914.
It can be produced by the method described in No. 5 etc.

Examples of the synthetic resin emulsion used in the photosensitive composition of the present invention include polyacrylic ester, ethylene-vinyl acetate copolymer, polyvinylidene chloride, polyvinyl acetate, polyvinyl chloride, copolymers or mixtures thereof, etc. There are many things that can be mentioned.

Furthermore, conventionally known water-dispersible coloring pigments, water-soluble dyes, leveling agents, stabilizers, matting agents, etc. can be added to the photosensitive composition of the present invention, if necessary.

The photosensitive composition of the present invention is composed of a water-soluble polymer having a photosensitive component-adding group and a synthetic resin emulsion, and the solid proportion of the water-soluble resin having a photosensitive component-adding group and the synthetic resin emulsion is 3: The ratio is 97 to 80:20, more preferably 5:95 to 40:60. If the amount of the water-soluble resin having a photosensitive component addition group is too large, the water resistance of the image will decrease and the image will fall off during development. Furthermore, the sensitivity of the formed photosensitive layer is significantly reduced. If the amount of synthetic resin emulsion is too large, developability and image quality will deteriorate. If the value is significantly outside the above range, no image can be obtained. Furthermore, when adding colorants, the amount of coloring pigments is usually 30% or less, and the amount of water-soluble dyes is 10% or less based on the total solid content of the water-soluble resin having a photosensitive component addition group and the synthetic resin emulsion. . The above components constituting these photosensitive compositions are prepared by being dissolved or dispersed in water or a water/alcohol mixture.

The photosensitive composition of the present invention thus prepared is coated onto a support to produce a positive image forming material. Polyethylene terephthalate, polypropylene, as a support
Examples include plastic films such as polyethylene, polyvinyl chloride, polystyrene, polycarbonate, and triacetate, glass plates, and paper made waterproof by laminating polyethylene or polypropylene on both sides. In addition, in order to provide writing properties with pencil, ink, ballpoint pen, etc. on one or both sides, a sand matte film made by sandblasting, an etched matte film etched with alkali, and other plastic films suitable for drafting, and a white pigment kneaded into the grains. Opalescent film can also be used. The photosensitive layer may be applied directly to the support, but in order to improve adhesion, it is desirable to perform corona radiation treatment, application of a brimer treatment agent, or adhesive treatment using a combination of these in advance. As the primer treatment agent, phenol resin, polyester resin, urethane resin, vinylidene chloride-vinyl acetate copolymer, vinylidene chloride-acrylonitrile copolymer, etc., and mixtures thereof are used, and the amount of 0.1 to 2. A coating thickness of 0 μm is preferred.

Coating onto the support may be performed by any method such as a spin coating machine, roll coating, barcoding, brush coating, or the like. The coating amount is such that the dry coating thickness is about 1 to 5 μm, preferably about 2 μm.
It is about m. The thinner the coating film, the better the resolution of the image.

After coating, it is usually dried with hot air at a temperature of about 90° C. or less, but air drying may also be used.

A positive image-forming material prepared using the photosensitive composition of the present invention is image-formed by the following steps.

(1) Exposure A manuscript is placed over the photosensitive composition-coated surface of the prepared image forming material, and is irradiated with actinic light from various mercury lamps, carbon arc lamps, xenon lamps, metal halide lamps, ultraviolet fluorescent lamps, etc.

(2) Immersion in water or warm water The exposed image forming material is immersed in water or warm water to swell the non-image areas. The water temperature at this time is not particularly limited, but higher temperatures can speed up the swelling of the non-image area and shorten the immersion time. The water temperature depends on the selection of each component constituting the photosensitive composition, but from the viewpoint of workability,
℃, more preferably a water temperature of 25 to 45°C is chosen. The immersion time is determined by the time required for the non-image area to swell sufficiently.

(3) Removal of non-image areas: The photosensitive surface of the soaked image forming material is rubbed with a sponge or the like moistened with dry water to remove non-image areas. Then dry.

(Examples) In order to further clarify the present invention, Examples are shown below, but the present invention is not limited to these.

Example 1 Liquid A (photosensitive liquid) However, a carbon black dispersion liquid was obtained by dispersing in an ink mixer for 3 hours with the following formulation.

Coat liquid A on one side of a 75 μm thick polyethylene terephthalate film using a spin coating machine, and apply 90°C with hot air at 90°C.
It was dried for a second to form a photosensitive layer with a thickness of 2 μm. Next, a positive original was brought into close contact with the photosensitive layer, and exposed for 10 seconds from a distance of 1 TrL using a 2 kW ultra-high pressure mercury lamp. This product was immersed in warm water at 15°C for 60 seconds to sufficiently swell the non-image area, and then the photosensitive surface was rubbed with a sponge soaked in water to remove the non-image area, resulting in a black, sharp optical density of 1. Twenty relief positive images were obtained.

Example 2 Liquid B (photosensitive liquid) In the same manner as in Example 1, liquid B was applied onto one side of a 75 μm thick polyethylene terephthalate film and dried to form a 2 μm thick photosensitive layer. Then, a 2 kV ultra-high pressure mercury lamp was used to
After exposing the photosensitive layer for 4 seconds at a distance of The image area was removed and a colorless and transparent positive relief image was obtained.

Example 3 Liquid C (photosensitive liquid) 35.0 parts by weight of L water Coat liquid C on one side of a polyethylene terephthalate film with a thickness of 75 μm using a spin coater, dry it with hot air at 90°C for 60 seconds, and then A photosensitive layer having a thickness of 1.5 μm was formed. Next, a positive original was brought into close contact with the photosensitive layer, and exposed for 12 seconds from a distance of 1 m using a 2 kW ultra-high pressure mercury lamp. This product was immersed in warm water at 15°C for 60 seconds to sufficiently swell the non-image area, and then the photosensitive surface was rubbed with a sponge soaked in water to remove the non-image area, resulting in a sharp black color with an optical density of 0.
Eighty-five relief positive images were obtained.

Example 4 Liquid D (photosensitive liquid) Liquid D was applied to one side of a polyethylene terephthalate film with a thickness of 75 μm using a rotary coating machine, and heated with hot air at 90°C for 6 hours.
It was dried for 0 seconds to form a photosensitive layer with a thickness of 1.5 μm.

Next, a positive original was brought into close contact with the photosensitive layer, and exposed for 12 seconds from a distance of 1 m using a 2 kW ultra-high pressure mercury lamp.

This product was immersed in warm water at 40°C for 30 seconds to sufficiently swell the non-image area, and then the photosensitive surface was rubbed with a sponge soaked in water under running water to remove the non-image area. A relief positive image with a density of 1.0 was obtained.

May 17, 1985 Commissioner of the Japan Patent Office / JX711 Hand β Husband 4, content of amendment in the detailed explanation of the invention in the agent's specification 1, page 2, line 16 of the letter of specification: 2. Corrected "to create" to "to create" 2. Corrected "for creation" to "for creation" on page 4, line 16 of the statement box, 3. In the 1st and 2nd lines of page 6 of the specification box, the words ``soaked in water'' were corrected to ``soaked in water or hot water.'' 4. In the 13th line of page 9 of the specification letter, the words ``polyvinyl chloride,'' were replaced with ``Polyvinyl chloride,''"Polyvinyl chloride, polyester," Correction 5, "Created" on page 12, line 14 of the specification box was corrected to "manufactured" 6, "Expedited" on page 13, line 3 of the specification Corrected the statement to "Hurry up"

Claims (2)

[Claims] (1) The following general formula ( I
) and (II) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・(
I) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・(
II) (However, in the above formula, R_1 and R_2 each independently represent a hydrogen atom or an alkyl group, Y^- is a conjugated basic ion of an acid, and * is a bond bonded to a water-soluble polymer via a linking group. ) A synthetic resin emulsion and a water-soluble polymer having at least one selected from the stilbazolium group and stilquinolium group shown as a photosensitive component addition group, and a colorant if necessary. A positive photosensitive composition. (2) The photosensitive composition according to claim 1, wherein the water-soluble polymer is at least one of polyvinyl alcohol, gelatin, and casein.