JP2687021B2 - Color relief image forming method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention provides a relief by removing a non-image part of an image forming layer containing a color pigment by applying a liquid containing water as a main component and circulating it. For details on the method of forming an image,
The present invention relates to a means for removing a color pigment mixed in the liquid, which causes contamination of the non-image area.

[Prior Art] In a color proofing material, a lithographic printing plate material and the like, an image forming treatment is known in which a non-image portion of an image forming layer provided on a support is removed to form a relief image. In such an image forming process, as a means for removing the non-image part of the image forming layer containing a color pigment, while circulating and reusing a liquid containing water as a main component, which is generally called an etching liquid or a rinse liquid, An image forming method of forming a relief image by supplying the image forming layer and removing the color pigment-containing layer in the non-image portion by a physical means is disclosed in JP-A-58-48056 and JP-A-60-193551. Known by.

In such an image forming process, in order to completely remove the color pigment contained in the image forming layer from the non-image area, it is necessary to supply a large amount of rinse liquid to the non-image area, and this rinse liquid is recycled and reused. ing. In such recycling and reuse, the rinse liquid is gradually contaminated by the color pigment in the removed non-image area. The color pigment floating in the rinse liquid has a problem in that it is redeposited on the surface of the non-image area where the image forming layer has been removed and stains occur in the non-image area.

[Problems to be solved by the invention]

Therefore, an object of the present invention is to remove the non-image part of the image forming layer containing a color pigment by physical means while applying a liquid containing water as a main component, and the liquid is recycled and reused. It is an object of the present invention to provide a method for forming a colored relief image in which the problem that the liquid is not contaminated with the coloring material in the image forming direction and the non-image area is contaminated by the contamination is solved.

[Means for solving the problem]

The above-mentioned object of the present invention is a method of forming a relief image by removing the adhesive pigment-containing layer in the non-image area by physical means while applying a liquid containing water as a main component to the coloring pigment-containing layer while circulating and reusing it. In the above method, a colored relief image forming method is characterized in that the liquid contains a water-dispersible substance having an electric charge and a self-sedimenting substance having an electric charge.

 Hereinafter, the present invention will be described in detail.

Examples of the color pigment-containing layer in the present invention include a photoconductive layer containing a light-sensitive pigment, a resin for a binder, etc. in a photosensitive material for plate making by electrophotography.

Examples of the photoconductive pigment include JP-A-47-30330 and JP-A-56-30330.
-5552 and other perylene pigments, JP-A-47-30331
Quinacridone pigments described in JP-A-47-18543 and bisbenzimidazole pigments described in JP-A-47-18543.
No. 44, No. 55-98754, No. 55-126254, No. 55-163543, polycondensed aromatic ring compounds, JP-B-44-16474
No. 48-30513, JP-A-56-321465, and other azo pigments, JP-B-50-7434, JP-A-47-37543, 55-
No. 11715, No. 56-1944, No. 56-9752, No. 56-2352, No.
56-80050, etc., Disazo pigments, JP-B-44-126
71, 40-2780, 52-1667, 46-30035, 49
-17535, JP-A-49-11136, 49-99142, 51-109
There are organic photoconductive pigments such as phthalocyanine pigments and inorganic photoconductive pigments such as ZnO described in JP-A Nos. 841 and 57-148745.

Examples of the binder resin include alkali-soluble resins such as phenol resins, acrylic acid resins, crotonic acid resins, phthalic acid resins, and maleic acid resins described in JP-A-54-134632 and JP-A-55-105254. Acid group-containing resin,
And a hydrocarbon polymer such as polystyrene, styrene-butadiene copolymer, polyisobutylene or the like, which is a relatively alkali-insoluble resin used in combination with the acid group-containing resin within a range that does not hinder the removal of the photoconductive layer by an alkaline aqueous solution; Polyvinyl chloride, chlorinated polyethylene, polyvinyl acetate,
Vinyl resins such as polyvinyl acetal, polyvinyl butyral and polyvinyl ether; silicone resins; polyamide resins; polyurethane resins; urea resins; melamine resins;
Polycarbonate resin; modified or unmodified rosin,
Examples include natural resins such as balsam.

The photoconductive layer may contain an additive, and as the additive, a sensitizer for adjusting the sensitivity or the photosensitive wavelength range is disclosed in JP-A-47-30330, JP-A-47-30331, and JP-A-47-30331. 47-30332,
55-161250 and other electron-donating substances described in JP-A-47-
30330, 55-153948, etc., electron-accepting substances, and xanthene dyes such as rose bengal, eosin S, fluorescein and phloxine; bromphenol blue, bromcresol purple, phenol sulfophthale such as chlorophenol red Rain dyes; Triphenylmethane dyes such as Alphazurin 2G, Pontacyl Brilliant Bull-FCF, Acid Violet 6B;
Examples include various dyes such as diphenylmethane dyes such as auramine; acridine dyes such as acridine yellow and acridine orange; rhodamine dyes such as sulfoledamine B and acid eosin G.

Examples of the other color pigment-containing layer include a color photosensitive layer of a color proof material composed of a photosensitive resin and a color pigment.

The colored photosensitive layer is imagewise removed by imagewise exposure with ultraviolet light or the like to form a colored relief image.

As the binder constituting these layers, a polymer compound which is film-forming and solvent-soluble and can be dissolved or swelled in a developing solution is used. From the viewpoint of adhesion performance, a novolac resin obtained by polycondensing at least one phenol with an active carbonyl compound is preferable.

As the novolak resin obtained by the polycondensation,
Phenol formaldehyde novolac resin, m-cresol formaldehyde novolac resin, phenol-m-
Cresol / formaldehyde copolycondensate resin, phenol / p-cresol / formaldehyde copolycondensate resin, m-cresol / p-cresol / formaldehyde copolycondensate resin, o-cresol / p-cresol / formaldehyde copolycondensate resin , Phenol / o-cresol / m-
Examples thereof include cresol / formaldehyde copolycondensate resin, phenol / o-cresol / p-cresol / formaldehyde copolycondensate resin, and phenol / m-cresol / p-cresol / formaldehyde copolycondensate resin.

A preferred novolac resin is phenol formaldehyde novolac resin, the molecular weight of which is weight average molecular weight Mw.
Is preferably in the range of 3500 to 500, and the number average molecular weight Mn is in the range of 1000 to 200.

Dyes and pigments are added as coloring substances to the colored photosensitive layer. In particular, when used for color proofing, pigments and dyes having the same color as the ordinary colors required there, i.e., yellow, magenta, cyan, and black, are required, but other metal powders, white pigments, fluorescent pigments, etc. used. The following example:
Some of the many pigments and dyes known in the art. (CI stands for color index).

Vicritoria Pure Blue (CI 42595) Auramine (CI 41000) Catillon Brilliant Flavin (CI Beshk 13) Rhodamine 6GCP (CI 45160) Rhodamine B (CI 45170) Safranin OK70: 100 (CI 50240) Erioglaucin X (CI 42080) First Black HB (CI 26150) No.1201 Lionol Yellow (CI 21090) Lionol Yellow GRO (CI 21090) Shimla Fast Yellow 8GF (CI 21105) Benzidine Yellow 4T-564D (CI 21095) Shimla Fast Red 4015 (CI 12355) Lionol Red 7B4401 (CI 15830) Fastgen Blue TGR-L (CI 74160) Lionol Blue SM (CI 26150) Mitsubishi Carbon Black MA-100 Mitsubishi Carbon Black # 30, # 40, # 50 Colorants for the above colored photosensitive layers The ratio of / binder is known to those skilled in the art in consideration of the target optical density and the removability of the colored photosensitive layer from the developer. It can be determined by the method. For example, the content of a dye is suitably 5% to 75% by weight, and the content of a pigment is suitably 5% to 90% by weight.

The thickness of the colored photosensitive layer can be determined by a method known to those skilled in the art according to the target optical density, the type of the coloring agent (dye, pigment, carbon black) used in the colored photosensitive layer and its content. Within the allowable range, the smaller the thickness of the colored photosensitive layer, the higher the resolution and the better the image quality. Therefore, the film thickness is 0.1-5 g /
It is usually used in the m ² range.

The colored photosensitive layer contains a quinonediazide compound as a photosensitive plastic material. Specifically, 1,2-benzoquinone diazide-4-sulfonyl chloride, 1,2-naphthoquinone diazide-4-manifonyl chloride, 1,2-naphthoquinone diazide-5-sulfonyl chloride, 1,2-naphthoquinone diazito- A compound obtained by condensing 6-sulfonyl chloride and a compound containing a hydroxyl group and / or an amino group is preferably used.

Examples of the hydroxyl-containing compound include trihydroxybenzophenone, dihydroxyanthraquinone, bisphenol A, phenol novolak resin, resorcinol benzaldehyde condensed resin, and pyrogallol acetone condensed resin.

Examples of the amino group-containing compound include aniline, p-aminodiphenylamine, p-aminobenzophenone 4,4'-cyaminodiphenylamine and 4,4-diaminobenzophenone.

With regard to the photosensitive compositions such as quinonediazide compounds, including those described here, see “Light S” by J. KOSAR.
ensitive System "(Wiley & Sons, New York, 1965) and Nagamatsu, Inui" Photosensitive Polymer "(Kodansha, 1977).

The “liquid containing water as a main component” in the present invention is a liquid used when removing the non-image portion from the color pigment-containing layer. Here, having water as the main component means at least the solvent.
It means that 50% by weight is water, and preferably 90% by weight or more is water.

Specific examples of the liquid include a processing liquid called an etching liquid and a rinse liquid, which is a processing liquid used for removing the non-image portion of the color pigment-containing layer as described above. (Hereinafter, the "liquid containing water as a main component" will be referred to as "ring liquid etc.") The etching liquid is an eluent capable of dissolving and removing the content of the coloring pigment, and is an alkali metal hydroxide or an alkali metal silicate. , An alkali metal phosphate and / or a metal aluminate, water and, if necessary, a strong alkaline aqueous solution of pH 12 or more, which comprises a surfactant and other additives. Specifically, JP-A-48-15535, 53-82334, 54-62004,
52-127338, 53-96307, 50-144502, 55-2
No. 759, No. 55-25100, No. 55-95946, No. 55-115039,
Examples of the solution include sodium silicate or potassium silicate described in JP-A Nos. 56-142528 and 50-51324.

In addition, the etchant solution may be, for example, JP-A-51-77401.
No. 51-80228, No. 53-44202 and No. 55-52054, anionic surfactants as described in JP-A Nos. 63-200154 and 63-88553, etc. A nonionic or cationic surfactant as described in 1., an organic solvent having a solubility in water of 10% by weight or less at room temperature, an alkaline agent, water, and an aqueous solution containing an antifouling agent if necessary.

Further, a common developer for a negative PS plate and a boji PS plate described in JP-A-60-130741 is also included.

Examples of the rinse liquid include an aqueous solution of a surfactant.

Examples of the surfactant include polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene polystyryl phenyl ether, polyoxyethylene polyoxypropylene alkyl ether, glycerin fatty acid partial esters, and sorbitan fatty acid partial esters. , Pentaerythritol fatty acid partial ester, propylene glycol monofatty acid ester, sucrose fatty acid partial ester, polyoxyethylene sorbitan fatty acid partial ester, polyoxyethylene sorbitol fatty acid partial ester, polyethylene glycol fatty acid ester, polyglycerin fatty acid partial ester, Polyoxyethylenated castor oil, polyoxyethylene glycerin fatty acid partial ester, fatty acid diethanolamide , N, N-Bis-2-hydroxyalkylamines, polyoxyethylenealkylamines, triethanolamine fatty acid esters, nonionic surfactants such as trialkylamine oxides, fatty acid salts, abithienates, hydroxyalkane sulfonic acid salts,
Alkane sulfonates, dialkyl sulfone succinate ester salts, linear alkylbenzene sulfonates,
Branched-chain alkylbenzene sulfonates, alkylnaphthalene sulfonates, alkylphenoxy polyoxyethylene propyl sulfonates, polyoxyethylene alkyl sulfophenyl ether salts, N-methyl-N-oleyl taurine sodiums, N-alkyl sulfosuccinic acid monoamides Disodium salts, petroleum sulfonates,
Sulfated castor oil, sulfated beef leg oil, sulfuric acid ester salts of fatty acid alkyl esters, alkyl sulfuric acid ester salts, polyoxyethylene alkyl ether sulfuric acid ester salts,
Fatty acid monoglyceride sulfuric acid ester salts, polyoxyethylene alkylphenyl ether sulfuric acid ester salts, polyoxyethylene styryl phenyl ether sulfuric acid ester salts, alkyl phosphoric acid ester salts, polyoxyethylene alkyl ether phosphoric acid ester salts, polyoxyethylene alkylphenyl ether phosphoric acid Ester salts, partially saponified products of styrene-maleic anhydride copolymers, partially saponified products of olefin-maleic anhydride copolymers, anionic surfactants such as naphthalene sulfonate formalin condensates, alkylamine salts , Quaternary ammonium salts, polyoxyethylene alkylamine salts, cationic surfactants such as polyethylene polyamide derivatives, carboxybetaines, aminocarboxylic acids, sulfobetaines , Amino acid esters, amphoteric surfactants such as imidazolines and the like.

Among the above-mentioned surfactants, those with polyoxyethylene can be read as polyoxyalkylenes such as polyoxymethylene, polyoxypropylene, and polyoxybutylene, and those surfactants are also included. The same applies to the description of.

The above surfactants may be used alone or in combination of two or more, and are used in the range of about 0.1 wt% to about 20 wt% in the aqueous solution.

The pH of the aqueous solution containing the surfactant in the present invention is 1 to 12.
Can be In order to adjust the aqueous solution to this pH, either or both of an acid and a water-soluble salt as a buffer can be contained.

The details of the above-mentioned buffering agent are described in, for example, "Chemical Handbook Basic Edition II" edited by The Chemical Society of Japan, February 20, 1972, 5th edition, published by Maruzen Co., Ltd., pages 1312 to 1320, and these are applied as they are. can do.

As the acid and the water-soluble salt, molybdic acid, boric acid,
Inorganic acids such as nitric acid, sulfuric acid, phosphoric acid and polyphosphoric acid, and acids such as acetic acid, oxalic acid, tartaric acid, benzoic acid, succinic acid, citric acid, malic acid, lactic acid, p-toluenesulfonic acid and other water-soluble organic acids I can give you some salt. The above acids and water-soluble salts may be used alone or in combination of two or more.

From the viewpoint of removability of the non-image part layer, it is preferable that the supply amount of the liquid containing water as a main component to the color pigment-containing layer in the present invention is 2 l / m ² or more.

In the present invention, the water-dispersible substance having a charge is a substance that does not precipitate in water and is in the form of fine particles that stably exist in water due to electric repulsion from each other. It does not mean a substance in a solvated state or a state in which it is solvated as an ion such as salt, that is, in a dissolved state. The size of the fine particles is in the range of 0.01 to 1 μm, preferably 0.01 to 0.5 μm. Preferred examples of such substances include colloidal alumina, colloidal silica and synthetic resin emulsions.

Examples of the synthetic resin emulsion include polyacrylic acid ester or its copolymer, polyacrylonitrile or its copolymer, polystyrene or its copolymer, polyethylene or its copolymer, polyvinyl chloride or its copolymer, polyvinylidene chloride or its copolymer, polyvinyl acetate or Mention may be made of latex-like polymer compounds such as copolymers thereof, resole resins or copolymers thereof, ionomer resins, polymethylmethacrylate or copolymers thereof, polybutadiene or copolymers thereof.

In the present invention, the substance having an electric charge and having a self-sedimentation property is a substance which causes a sedimentation phenomenon when it is stirred and mixed in water alone and then left to stand. The particles each have an electric charge, and although there is mutual electric repulsion between diffusion due to Brownian motion and that due to Brownian motion, sedimentation occurs because gravity is stronger than that. Such substances generally have a wide particle size distribution, and there is a difference in the sedimentation velocity such that large particles are fast but small particles are slow.
In the present invention, the substance having an electric charge and having a self-sedimentation property means a substance having a particle size of 1 μm to 3 mm in a weight ratio of 80% or more, preferably 90% or more.

Preferable examples of such substances include kaolin, clay, activated clay, bentonite, calcium carbonate and silica sand.

Further, in the present invention, by combining at least one kind of a substance having an electric charge and having water dispersibility and a substance having an electric charge and having a self-precipitation property, an excellent aggregation effect is exhibited. About 2 kinds or 2
Similar effects or higher effects can be obtained by combining two or more kinds.

Next, the means for containing the water-dispersible substance having a charge and the self-precipitating substance having a charge in the rinse liquid in the present invention will be described.

The order of adding the water-dispersible substance and the self-precipitating substance to the rinse liquid may be arbitrary, and after adding the water-dispersible substance to the rinse liquid and mixing, the self-precipitating substance is added and mixed. It is also possible to mix them by adding them at the same time, or vice versa, or adding them in advance.

The content of the water-dispersible substance is preferably 0.05 to 10%, more preferably 0.1 to 5%. The self-sedimenting substance is
0.05 to 10% is preferable, and 0.1 to 5% is more preferable. The ratio of the both is preferably 1:10 to 100: 1, and more preferably 1:20 to 20: 1.

As for the timing of addition, it may be added to the rinse liquid before the start of circulation reuse, or may be added during the circulation reuse.

The water-dispersible substance and the self-precipitating substance according to the present invention (hereinafter, these two are collectively referred to as “coagulant”),
The concentration is reduced by being adsorbed by the eluted pigment in the color pigment-containing layer and removed by a filter or the like, but this concentration decrease may be supplemented by supplementing the aggregating agent.

In the present invention, the physical means for removing the color pigment-containing layer in the non-image area is arbitrary. As the physical means, a method of rubbing the color pigment-containing layer, for example, a method of rubbing using a rotating roller-shaped rubbing member, a method of rubbing by rotating a flat plate-shaped rubbing member, and a front-back rubbing member of a flat plate-shaped rubbing member Examples thereof include a method of rubbing by sliding left and right, and a method of rubbing by sliding back and forth and / or left and right while rotating a flat plate-shaped rubbing member.

As the rubbing member, for example, a brush, sponge, cloth or the like can be used.

The physical removing means is preferably rubbing with a brush from the viewpoint of removability of the non-image part layer. Further, it is preferable from the viewpoint of removability of the non-image part layer to rub the color pigment-containing layer after immersing it in a rinse liquid or the like.

As other physical means, it is also possible to use a method of spraying a treatment liquid such as an etching liquid or a rinsing liquid on the color pigment-containing layer, a method of blowing high-pressure air, a method of irradiating ultrasonic waves, or a method of giving vibration. . The etching liquid may be a liquid containing abrasive powder, and the abrasive powder may be used for honing.

In the present invention, suspended matter in the rinse liquid or the like that is recycled and composed of the pigment of the non-image part layer that has been removed forms huge particles by being adsorbed by the coagulant according to the present invention, and is removed by the filter. Will be easier. Therefore, in the present invention, it is preferable to apply a rinse liquid or the like to the color pigment-containing layer through a filter.

As the filter, those commonly used in the elution type development process can be used. As a preferable filter, for example, a filter housing made of stainless steel or vinyl chloride resin is provided so that the filter can be easily replaced. As the size of the housing, a generally used columnar type having a length of 100 to 250 mm and a diameter of 50 to 100 mm can be used.

As the material of the filter, there are polyester, polypropylene, acrylic resin, epoxy resin, cellulose acetate, etc., and a commonly used one obtained by fold-folding these into the above size can be used. In the present invention, the pore size of these filters is 10 to 100 μm.
Are preferred. In addition, examples of the filter include a wound material of the above material, a sponge-shaped material, and the like.

As a preferable experimental mode of the present invention, there is a mode in which the color pigment-containing layer forming a relief image is provided on a grained support. According to the present invention, in such an aspect, the effect of preventing contamination of the non-image area is particularly remarkable. Examples of the grained support include the supports described in JP-A-62-175757, page 6, lower right column, line 15 to page 6, upper right column, line 11.

A waste liquid treatment technology for precipitating and separating fine particles in the waste liquid by using the flocculating agent used in the present invention as the dissolution liquid waste of the elution type image forming material is described in JP-A-58-195807. It has been unexpected that inclusion of such an aggregating agent in the processing liquid such as the etching liquid or the rinse liquid can prevent the non-image area from being contaminated.

〔Example〕

Hereinafter, the present invention will be described more specifically with reference to examples.

Example 1 A toner image using a liquid toner is formed according to an electrophotographic method on an electrophotographic printing plate having an electrophotographic photosensitive layer in which a copper phthalocyanine pigment is dispersed in a phenol resin on an aluminum plate subjected to a graining and hydrophilic treatment. did.

The electrophotographic printing plate thus obtained is processed by the processing apparatus shown in FIG. 1 as follows to remove the photosensitive layer in the non-image area where the toner image is not formed to form a colored relief image. did.

In the first treatment section 3, a 4% aqueous solution of sodium metasilicate having a pH of 13 was adjusted to a liquid temperature of 30 ° C. in a tank 4 and supplied onto the plate surface by a pump P ₁ .

In the second processing part 7, 10% of tap water is colloidal silica 10%
A treatment liquid containing 4 g of an aqueous dispersion (Snowtex N, manufactured by Nissan Chemical Industries, Ltd.) and 4 g of calcium carbonate was stored in a tank 8.
4 l / m ^{2 was} supplied onto the plate by the pump P ₂ . Second processing unit 7
Then, a brush 9 was used to rub the plate. still,
A filter with a pore size of 50 μm between the pump P ₂ and the shower 10.
11 were provided.

The pigment is mixed in the treatment liquid because the pigment is removed in the second treatment section 7, but this pigment aggregated and settled in the tank 8 and the coloring concentration was low. Moreover, these aggregates can be easily removed with a filter, and the treatment liquid with a low coloration was always supplied from the shower 10, and the relief image obtained was clear without background stain.

In FIG. 1, reference numeral 1 is a conveyance path of a processing object having a color pigment containing layer, 2 is a conveyance roller, 5 is a shower, and 12 is a drying section.

Comparative Example 1 When the same treatment as in Example 1 was carried out except that colloidal silica was not added to the treatment liquid of the second treatment part 7 in Example 1, the pigment did not aggregate and settle, and the coloring concentration of the treatment liquid was The relief image obtained rose, and was also an unclear image in which background stain was generated by the pigment.

Example 2 A colored photosensitive layer having the following composition was provided on a polyethylene terephthalate film having a thickness of 50 μm which had been subjected to a release treatment.

2,3,4-trihydroxybenzophenone-naphthoquinone-
1,2-diazide sulfonic acid ester 0.616g Phenol formaldehyde novolac resin 4.384g Seika Fast Carmine 1483 (Dainichi Seika) 0.68g A color separation positive film is overlaid on the image forming material thus obtained and exposed to ultraviolet light. It was

Next, development processing was carried out by the processing apparatus shown in FIG.

In the first processing section 13, a processing solution composed of an aqueous sodium carbonate solution is supplied from the tank 14 to the photosensitive layer surface (lower side) by the pump P ₁ .

In the second processing unit 17, 10 l of tap water was added to 10 l of colloidal alumina.
% Water dispersion (Cataloid AS: manufactured by Catalysts & Chemicals Co., Ltd.) 50 g and silica sand (Kanto Chemical Co., Inc. reagent 5 g) added to tank 18
Then, 10 liters per 1 m ² of the photosensitive layer area was supplied to the surface of the photosensitive layer by the pump P ₂ . In the second processing section 17, the surface of the photosensitive layer was rubbed with the brush 9. Pump P ₂ and shower
A filter 11 was provided between the nineteen.

The pigment is mixed in the treatment liquid because the pigment is removed in the second treatment section 17, but this pigment is aggregated and settled in the tank 18, and the increase in the coloring concentration of the treatment liquid itself was low. Further, this agglomerate can be easily removed by a filter, and it was possible to always supply a treatment liquid having almost no color from the shower 19. Therefore, the image-forming material obtained by the development treatment had a clear image without scumming.

In FIG. 2, 22 is a water washing part and 24, 25, 26 are heaters.

Comparative Example 2 The same treatment was carried out as in Example 2 except that colloidal alumina was not added to the treatment liquid in the second treatment section, and the pigment mixed in the treatment liquid did not cause any aggregation or sedimentation and the coloring concentration of the treatment liquid was Gradually, the pigment adhered to the non-image area of the image-forming material to cause background stain, and only an unclear image was obtained.

〔The invention's effect〕

According to the present invention, a non-image portion of an image forming layer containing a color pigment is removed by a physical means while applying a rinse liquid or the like, and a relief image in which the rinse liquid or the like is circulated and reused is formed. In the method, the drawback that the rinsing liquid or the like is not contaminated by the color pigment and the contamination causes stains on non-image areas is improved.

[Brief description of the drawings]

1 and 2 are schematic cross-sectional views of the processing apparatus used in the embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Conveyance path 3, 13 ... 1st processing part 4, 8, 14, 18, 23 ... Tank 7, 17 ... 2nd processing part 11 ... Filter 12 ... Drying part 22 ... Water washing part

Claims (1)

(57) [Claims] 1. A method of forming a relief image by removing a color pigment-containing layer in a non-image area by a physical means while applying a liquid containing water as a main component to the color pigment-containing layer while circulating and reusing it. A method for forming a colored relief image, characterized in that the liquid contains a water-dispersible substance having an electric charge and a self-sedimenting substance having an electric charge.