JPS58100862A - Electrophotographic printing plate material and manufacture of printing plate using it - Google Patents

Abstract

PURPOSE:To obtain a printing plate superior in printing resistance, etc., by using a material obtained by forming an electrophotographic sensitive layer contg. a specified triphenylmethan polymer, a resin binder, and a sensitizer on a substrate having a water-retentive or oily printing ink-repelling, and conductive surface. CONSTITUTION:A printing plate material having a photosensitive layer removable with a basic soln. or org. solvent is prepared by coating a substrate of an aluminum plate or the like having a water-retentive or an oily printing ink-repelling, and a conductive surface with a coating liquid material contg. a sensitizer and a resin binder, such as a styrene-maleic anhydride copolymer good in film-forming property and adhesion, etc., and a polymer represented by the right formula (R is 1-5C alkyl; X is H or CH3; Z is 1-5C alkylene or p-phenylene- alkylene: Q is H, CH3 , OCH3, NO2, CN, halogen, or amino disubstd. by CH3, C2H5, or the like; and n is 1-400), and drying the coated material, thus permitting the printing plate obtained from this material to have a sharp image free from stains on the nonimage area and superior printing resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel printing plate material using electrophotography and a method for producing a printing plate using the same. There are ↑ related to materials and methods of manufacturing printing plates using them.

Conventionally, as printing plate materials (printing original plates) using electrophotography, for example, Japanese Patent Publication No. 47-47610, Japanese Patent Publication No. 48
-40002, Special Publication No. 18525, Special Publication No. 18525, Special Publication No. 18525
Zinc oxide-resin dispersion offset printing plate materials described in Japanese Patent Publication No. 1-15766 and Japanese Patent Publication No. 51-25761 are known.

The method for producing a printing plate is to form a toner image by a normal electrophotographic method, and then treat the surface with ferricyanide or phosphate aqueous solution to make the non-toner image area hydrophilic, thereby producing a lithographic printing plate. Although the method is known,
As a lithographic printing plate, the non-image area has insufficient hydrophilicity, and once staining occurs, it is very difficult to recover.

Special Publication No. 37-17162, Special Publication No. 3B-7758,
In the organic photoconductor-resin printing plate materials described in Japanese Patent Publication No. 46-39405 and Japanese Patent Application Laid-Open No. 52-2437, for example, oxazole or oxadiazole compounds are combined with styrene-anhydride-r-leic acid copolymer. An electrophotographic photoreceptor is used in which a combined photoconductive insulating layer is provided on a grained aluminum plate, and after forming a toner surface edge on the photoreceptor using an electrophotographic method, the photoreceptor is coated with a non-alkaline organic solvent. A printing plate is formed by dissolving and removing the image area.

However, since the organic photoconductor and the binder are different compounds, especially when using a large amount of the organic photoconductor to increase sensitivity, the solubility of the organic photoconductor in the binder, phase separation, The problem was that unexpected problems such as crystallization of the body occurred.

In addition, triphenylmethane compounds are known as photoconductive compounds in ordinary electrophotography (Japanese Patent Publication No. 45-555); It is soluble in the petroleum solvent used. As a result, the triphenylmethane compound may be leached out of the layer containing the triphenylmethane compound, causing changes in the structure and performance of the layer, which is a problem that should be improved in practice.

at the end of the polycarbonate oligomer to prevent leaching of such triphenyl compounds.

Chemical attachment of triphenylmethane-based compounds is also described in US Pat. No. 6,660,085. However, even such compounds still have insufficient charge transport ability (and because the synthesis is complicated, it is difficult to control the content of triphenylmethane structure, which has charge transport ability, in the polymer). Moreover, it was impossible to contain this triphenylmethane structure at a high concentration.

The present inventors have conducted extensive research in order to improve the above-mentioned drawbacks of the conventionally known electrophotographic photosensitive printing materials, and as a result they have arrived at the present invention.

An object of the present invention is to provide an electrophotographic printing plate material using an electrophotographic photoreceptor with a clear single image without staining in non-image areas, and a method for constructing a printing plate using the same.

Another object of the present invention is to provide an electrophotographic printing plate material having excellent electrostatic properties such as charge retention and moisture resistance, and a method for constructing a printing plate using the same.

Another object of the present invention is to provide an electrophotographic printing plate material containing, in an electrophotographic photosensitive layer, a polymer having a polymerized structure of triphenylmethane, which is insoluble in petroleum solvents and having excellent film properties. An object of the present invention is to provide a method for manufacturing a printing plate using the present invention.

Still another object of the present invention is to provide an electrophotographic printing plate material containing an electrophotographic photosensitive layer that is easily removable with a basic liquid, an organic solvent, or a mixed liquid thereof, and a method for producing a printing plate using the same. It's about doing.

The present invention provides (1) water-retaining or oil-repellent printing ink properties;
and a support (1) having a conductive surface, a sensitizer provided thereon, an electrophotographic photosensitive layer (2) comprising a triphenylmethane polymer represented by the following general formula [1], and a resin binder. The electrophotographic photosensitive layer is a basic liquid.

An electrophotographic printing plate material that can be removed with an organic solvent or a mixed liquid thereof.

In the above formula, R is an alkyl group, X is a hydrogen atom or a methyl group, Y is a hydrogen atom or a methyl group, 2 is an alkylene group or a P-phenylenealkylene group, and Q is a hydrogen atom, methyl group, or methoxy group. , a di-substituted amino group, a nitro group, a cyan group or a halogen atom, L is 1 to 40
Represents an integer of 0.

and (2) after the electrophotographic photosensitive layer of the electrophotographic printing plate material described in item (1) is charged, imagewise exposed, and toner developed, the non-image portions of the electrophotographic photosensitive layer to which toner is not attached are removed. The present invention relates to a method for producing an electrophotographic printing plate, which includes a step of removing.

In the general formula [1], the alkyl represented by R has 1 to 5 carbon atoms. Preferably, it is an alkyl group having 1 to 3 carbon atoms, and specific examples thereof include methyl group, ethyl group, propyl group, butyl group, pentyl group, isopropyl group, isomethyl group, isoamyl group, and 5ec-butyl group.

The alkylene group represented by 2 is an alkylene group having 1 to 5 carbon atoms, preferably 1 to 3 carbon atoms, and specific examples thereof include a methylene group and an ethylene group.

trimethylene group, tetramethylene group, pentamethylene group, furopylene group, ethylethylene group, 1,3-butylene group, 2. ! There are l-zotylene group, imbutylene group, α-amylene group, and α, δ-amylene group.

The alkylene group of the P-phenylene dialkylene group has 1 to 3 carbon atoms. Preferred is a noalkylene group having 1 to 2 carbon atoms, and specific examples of the P-phenylene dialkylene group include a P-phenylene diethylene group (P-xylylene group, -
0H2-〇-CH2-), p-phenylenediethylene group, and P-phenylenedi(trimethylene/) group.

The di-substituted amino group represented by Q is a di-substituted amine group substituted with a methyl group or an ethyl group, and specific examples thereof include a dimethylamino group, a diethylamino group, and an N-methyl LN-ethylamino group. The position of Q may be any of the ortho position, meta position, and bara position relative to the bonding position of the methane carbon atom in the triphenylmethane structure.

preferably is an integer from 1 to 100.

Regarding the triphenylmethane polymer, which is the most important component in the present invention, various triphenylmethane polymers described in Japanese Patent Application Laid-Open No. 5-1972-PO933 and Japanese Patent Application No. 55-65052 can be used, but particularly preferred specific examples include: Examples include compounds shown in Table 1.

The electrophotographic photosensitive layer used in the present invention includes:

In addition to the triphenylmethane polymer, various sensitizers such as conventionally used dyes and other electron-accepting substances, and
A suitable combination of binders is added. Sensitizing compounds used include U.S. Pat. Nos. 2.732.301 and 2,6.
No. 70,287, No. 2,670,284, No. 2,67
No. 0,286, No. 3,250,615, No. 2.610
．． 5. Pyrylium dyes, fluorenes, thiazoles, and cyanine dyes described in No. 120, Japanese Patent Application No. 56-4734, etc. Carbocyanine dyes, merocyanine dyes, anthraquinone dyes, azo dyes, aromatic nitro compounds, ζ
Examples of the sensitizer include rubituric acid derivatives, thiobarbic acid derivatives, anthrone, and quinone, and preferred sensitizers include pyrylium salts, thiapyrylium salts, cyanines, triphenylmethane dyes, thiazine dyes, and oxazine dyes.

Specifically, thioflavin, crystal violet, rhodamine B, brilliant red, methylene blue, etc. are preferably used.

The amount of sensitizer used is 0.00 per dry electrophotographic photosensitive layer.
01 to 30% by weight can be added. Preferably 0
．． 005 to 10 weight category.

As the resin binder used in the present invention, various natural or synthetic resins can be selected from the viewpoints of film-forming properties, adhesion, printing durability, electrical properties, and the like. After the electrophotographic photosensitive layer is developed with the toner, these resin binders can be used to make the toner image a resist layer, and the portions to which the toner is not attached can be easily removed with an etching solution. As the etching solution, a basic liquid and/or an organic solvent can be practically used. Among these etching solutions, the basic liquids include sodium silicates such as sodium hydroxide, potassium hydroxide, sodium metasilicate, and sodium orthosilicate.

IJum (phosphoric acid) is useful, and various aromatic and kamorin group organic solvents can be used as organic solvents, but organic amines such as ethanolamine, methanol, ethanol, isozolononol, benzyl alcohol, etc. , ethylene dalycol.

Alcohol-based organic solvents such as glycerin are preferred.

Mixed liquids of these may also be used. However, in practice, it is preferable to use an alcohol-based organic solvent from the viewpoint of physiological and safety aspects.

Furthermore, surfactants and other additives may be added.

Examples of resins that can be removed with basic liquids include polymeric compounds containing acid anhydride groups, carboxyl groups, phenolic hydroxyl groups, sulfonic acid groups, sulfonamide groups, or sulfonimide groups. More specifically, examples of polymer compounds containing acid anhydrides include copolymers of styrene and maleic anhydride, copolymers of vinyl acetate and maleic anhydride, and polymer compounds containing carboxyl groups. Examples include styrene-itaconic acid copolymer, vinyl acetate-maleic acid copolymer, etc., or compounds represented by general formula [2].

R2 and R4 each represent a hydrogen atom or a methyl group, and may be the same or different.

R3 is an alkyl group having 1 to 18 carbon atoms such as a methyl group, ethyl group, propyl group, butyl group, and an alkyl group having 7 to 18 carbon atoms such as benzyA/group% phenethyl group, 3-phenylzorobyl group, etc.
represents 12 aralkyl groups.

Among these substituents, a methyl group is preferred for both R2 and R4, or a benzyl group is preferred for R.

xv! The molar ratio of y to , , is 5 to 604. Preferably it is 10-50.

Preferred examples of the polymer compound containing phenolic hydroxyl groups include phenol resins.

Phenol resins include phenol, O-cresol,
Preferred is a novolac resin obtained by condensing m-cresol or p-cresol with formaldehyde or acetaldehyde under acidic conditions.

The average molecular weight of the phenolic resin according to the present invention is 650 to 2
10,000 is preferable, and about 650 to 6,000 is particularly preferable.

Various resins are used as resins that can be removed with organic solvents, but as mentioned above, alcohol-based organic solvents are preferred in practice, so polyvinyl acetate-based resins and alcohol-soluble nylon are also used as resin binders. Alcohol-replaceable resins such as polyvinyl butyral resins and polyvinyl butyral resins are preferably used.

The triphenylmethane polymer used in the present invention has a weight range of 5 or more with respect to the electrophotographic photosensitive layer.

Preferably, the amount of the resin binder is 10% by weight or more, and the resin binder is added in an amount of 95% by weight or less, preferably 70% by weight or less.

The conductive support, which is a component of the printing plate of the present invention, has a surface that has characteristics suitable for a printing plate support, that is, can repel oil-based printing ink or retain water, and can be used as an electrophotographic light-sensitive material. Any material may be used as long as it has the necessary conductivity. Specifically, metal plates such as aluminum, zinc, iron, copper, bimetal plates such as copper-aluminum plates, copper-stainless steel plates, chrome-copper plates, chrome-m-aluminum plates, chrome-i-iron plates, the law of nature.

A conductive substrate with a hydrophilic surface such as a tri-metal plate such as Mu copper-stainless steel plate is used, and its thickness is 0.1 to 3.
1 m is preferable, and 0.1 to 1 m is particularly preferable.

On paper, plastic films such as polyethylene terephthalate, polyethylene, cellulose acetate, etc., and on them or on laminates thereof.

Supports that have been made conductive by vapor deposition or chemical plating with metals such as aluminum, silver, iron, chromium, and nickel, or by coating a resin layer in which a conductive substance is dispersed, are used. When the toner non-image area is removed by etching and the support surface is exposed, the support surface is relatively hydrophilic to the toner image area and can withstand operation as a printing plate. good.

In the case of a support having an aluminum surface, treatment in a grain chamber or immersion treatment in an aqueous solution of sodium silicate, potassium fluorozirconate, phosphate, etc.

Alternatively, it is preferable that surface treatment such as anodic oxidation treatment is performed. Further, as described in US Pat. No. 2714.066, an aluminum plate treated with +i in a sodium silicate aqueous solution after graining, and An aluminum plate which is anodized and then immersed in an aqueous solution of an alkali metal silicate is also preferably used.

The above anodizing treatment is performed using, for example, phosphoric acid or chromic acid.

Conducted by passing an electric current through an aluminum plate as an anode in an electrolytic solution consisting of an aqueous solution or a non-aqueous solution of inorganic acids such as sulfuric acid, boric acid, etc., organic acids such as oxalic acid, sulfamino acid, or their salts, or a combination of two or more of them. be done.

Also effective is silicate electrodeposition as described in US Pat. No. 3,658,662. Treatment with polyvinylsulfonic acid as described in DE 1,621,478 is also suitable.

These hydrophilic treatments are performed not only to make the surface of the support hydrophilic but also to prevent harmful reactions with the electrophotographic photosensitive layer provided thereon.

This is applied to improve adhesion to the electrophotographic photosensitive layer.

In the present invention, casein, polyvinyl alcohol, ethyl cellulose, and phenol resin are optionally provided between the conductive substrate and the electrophotographic photosensitive layer.

An alkali-soluble intermediate layer made of a styrene-maleic anhydride copolymer, polyacrylic acid, or the like may be provided for the purpose of improving the adhesion between the substrate and the electrophotographic photosensitive layer or the electrostatic properties of the electrophotographic photosensitive layer. .

In the present invention, if necessary, an overcoat layer is provided on the electrophotographic photosensitive layer that can be dissolved when the electrophotographic photosensitive layer is removed for the purpose of improving the electrostatic properties of the electrophotographic photosensitive layer, the development properties during toner development, or the image properties. It is possible to set up This overcoat layer is mechanically matted,
Alternatively, it may be a resin layer containing a matting agent.

Examples of agents include silicon dioxide, zinc oxide, titanium oxide, zirconium oxide, glass particles, alumina, starch monopolymer particles (eg, polymethyl methacrylate).

particles of poly-11 styrene, phenolic resin, etc.) and U.S. Patent No. 2,710,245, U.S. Patent No. 2.9
92.101 are included. Two or more of these can be used in combination. The resin used in the resin layer containing the matting agent is appropriately selected depending on the combination with the electrophotographic photosensitive layer removing liquid used. Specifically, for example, gum arabic, glue, gelatin, casein, cellulose 14 (fc toeha hiscose, methyl cellulose, ethyl cellulose, human 90 xyethyl cellulose, hydroxypropyl methyl cellulose).

carboquine methyl cellulose, etc.), starches (e.g. soluble starch, modified starch, etc.), polyvinyl alcohol, polyethyleneoxywhite polyacrylic acid.

Polyacrylamide, polyvinyl methyl ether.

Examples include epoxy resins, phenol resins (novolac type phenol resins are particularly preferred), polyamides, polyvinyl butyral, and the like. Two or more of these can be used in combination.

When producing an electrophotographic photosensitive layer containing a triphenylmethane polymer, triphenylmethane includes dichloroethane, dichloromethane, chloroform, tetrahydrofuran, and dioxane.

Examples include N,N-dimethylformamide and N-methylpyrrolidone. In addition, various additives such as surfactants and plasticizers may be added to the electrophotographic photosensitive layer. The electrophotographic photosensitive layer as described above is coated on the above-mentioned support to a dry film thickness of 1 .mu.'rIL-600 .mu.m, preferably *211rn to 60 prn. In the electrophotographic printing plate material of the present invention having such an electrophotographic photosensitive layer, the electrophotographic photosensitive layer is substantially uniformly charged in a dark place by a conventional electrophotographic method.

After imagewise exposure, a toner image is formed by toner development. Thereafter, by removing the electrophotographic photosensitive layer in the non-toner image area, a printing plate can be produced.

As a method for forming a toner image, various methods known in conventional electrophotography, such as cascade development, magnetic brush development, powder cloud 9 development, and liquid development, can be used. After development.

The toner image can be fixed by a known method such as heat fixing or pressure fixing. In preparing the printing plate of the present invention, after development, the toner image acts as a resist and the electrophotographic photosensitive layer in the non-image area to which toner is not attached is removed. It is preferable that the resin component contains a large amount of a resin component that has resist properties to an etching solution that removes the etching liquid. This resin component must have resistivity to an etching solution that removes the electrophotographic photosensitive layer.

For example, acrylic resin using methacrylic acid, methacrylic acid ester, etc., vinyl acetate resin, copolymer of vinyl acetate and ethylene or vinyl chloride, vinyl chloride resin,
Vinylidene chloride resins, vinyl acetal resins like polyvinyl butyral, polystyrene, styrene and butadiene.

Copolymers such as methacrylic acid ester, polyethylene,
Polypropylene and its chlorinated products, polyester resins (
For example, polyethylene terephthalate.

polyethylene isophthalate, polycarbonate of bisphenol A), polyamide resins (e.g. polycapramide, polyhexamethylene adipamide).

Examples include cellulose ester derivatives such as polyhexamethylene sebacumite), phenolic resins, xylene resins, alkyd resins, vinyl-modified alkyd resins, gelatin, and carboxymethyl cellulose, as well as waxes, polyolefins, and waxes. In addition, the toner may also contain a charge control agent, a coloring agent, and the like.

In the present invention, the relationship between the toner and the support having an oil-repellent printing ink surface is often the same.

The former is oleophilic and the latter surface is hydrophilic; in this case, the degree of oleophilicity and hydrophilicity is relative, and the oil-repellent printing ink property of the surface of the support is different from that of the toner image area. means that the oil-based printing ink must not remain attached to the support surface when the exposed support surface is adjacent;
Hydrophilicity of the support surface means that the support surface must not be so repellent to water as to be unable to retain water when the toner image area and the exposed support surface are adjacent; The lipophilic nature of the toner means that it must be so repellent to oil-based printing inks that it must not be impossible to retain the oil-based printing inks.
Oil-based printing ink.

It also may be water repellent (hydrophobic).

Since the triphenylmethane polymer used in the photosensitive layer of the electrophotographic printing plate material of the present invention is insoluble in petroleum-based organic solvents, liquid development is also possible and images with very good resolution can be obtained. At the same time, the triphenylmethane polymer has good compatibility with other resins, and because it itself has film-forming properties, it has various characteristics as a printing material, such as printing durability.

Next, the present invention will be specifically explained based on examples.

Example 1 Triphenylmethane polymer (I-1) in Table 1 0
．． 5 parts of the following sensitizing dye (3:1 0.
05 parts methylene chloride s
8.0 parts was uniformly dissolved, and this solution was placed on a 0.25 mm thick aluminum plate with a wire bar.
It was applied with a coater. The thickness of the electrophotographic photosensitive layer is approximately 7 μ
It was m. This sample was subjected to corona discharge (-6KV) in a dark place.
By doing so, the surface potential of the electrophotographic photosensitive layer is approximately -500V.
After being charged to , it was brought into close contact with a transparent original with a positive image and exposed. Next, add this to I 5 Opar H (1 petroleum solvent manufactured by Etsuo Standard 9) 1! Polymethyl methacrylate 5 dispersed in fine particles? The sample was immersed in a liquid developer containing a toner prepared by adding 0.01 P of zirconium naphthenate to obtain a positive toner image, which was then heated at 10 DC for 6 m seconds to fix the toner image. The sample prepared as above was mixed with 70i of sodium metasilicate hydrate and 140i of glycerin.
m1. Immerse for about 1 minute in a solution containing 550 ml of ethylene glycol/L/ and 150 ml of ethanol,
By lightly brushing, the toner non-image area was removed, the surface of the aluminum substrate of the support was exposed, and a printing plate with a clear image was obtained. When the printing plate thus prepared was subjected to offset printing using a conventional method, very clear printed matter could be printed.

Examples 2 to 4 In Example 1, triphenylmethane polymer (I-1
Except that (I-2), (I-3), and (I-7) were used instead of ), a good printing plate could be prepared by performing exactly the same operation.

Example 5 Triphenylmethane polymer (I-4) in Table 1 0
．． 5 parts of the following sensitizer [4) o.

5 parts methylene chloride” 8.0
The solution was uniformly dissolved and coated on a 0.25s+s+ aluminum plate.

The thickness of the electrophotographic photosensitive layer was approximately 7 μm. This sample was charged and exposed in the same manner as in Example 1.

By developing and etching, a good offset printing plate could be produced.

Example 6 Electrophotography was carried out on an aluminum substrate by the same procedure as in Example 1, except that 1.0 part of polyvinyl butyral (3000K, manufactured by Denki Kagaku Co., Ltd.) was used instead of the copolymer of polyvinyl methacrylate and methacrylic acid. A photosensitive layer was provided.

By subjecting this sample to corona discharge in the dark, the surface potential -
After image exposure, the toner image was formed by developing with the liquid developer used in Example 1 and fixing with heat. By immersing this in ethanol and lightly brushing it, the non-toner image area was removed, making it possible to produce an offset printing plate with a clear image.

Example 7 Triphenylmethane polymer (I-12) in Table 1
0.5 part sensitizing dye [3] 0.
05 parts methylene chloride 8.0
The mixture was uniformly dissolved and the same procedure as in Example 1 was carried out to form an electrophotographic photosensitive layer with a thickness of about 7 μm. A toner image was formed using the same procedure as in Example 1. After immersing this sample in an etching solution consisting of 5 parts of methyl cellosolve acetate and 1 part of monoethanolamine for about 1 minute,
By lightly brushindering, it was possible to produce an offset printing plate with a clear image.

Examples 8 to 11 In Example 7, as the triphenylmethane polymer, the first
A good offset printing plate could be produced by the same operation except that 1-16 to 1-16 were used instead of 1-12 in the table.

Procedural amendment February 11, 1981 Patent Application No. 199857 2, Title of invention Electrophotographic printing plate material and method for manufacturing printing plates using the same 3, Person making the amendment Relationship to the case: Patent application Person's name (520) Fuji Atsuma Film Co., Ltd. 1) Line 6 from the bottom of No. 16 of the statement, "Rensan Nato Vum J 04
Add organic acenes like IK F and Ethanolua.

2) Page 28, lines 4 to 6 from the bottom, [Organic amines such as ethanol, JvIllju].

6) Page 15, line 7, K after "benzyl group".

Add ``, methyl group, ethyl group, and tetravir group.''

4) Page 28, line 7 from the bottom, r 1o van/IJ
&delete.

Claims (1)

[Claims] +11 A support (1) having water-retentive or oil-repellent printing ink properties and a conductive surface, and a sensitizer provided thereon, represented by the following general formula [1]. It is composed of an electrophotographic photosensitive layer (2) made of wasalel triphenylmethane polymer and a resin binder, and the electrophotographic photosensitive layer is removable with a basic liquid, an organic solvent, or a mixed liquid thereof! Some electrophotographic printing plate materials. In the above formula, R is an alkyl group; , a di-substituted amino group, a nitro group, a cyan group or a halogen atom, n is 1 to 40
Represents an integer of 0. (2) A support having water-retentive or oil-repellent printing ink properties and a conductive surface (11 and a sensitizer provided thereon, a triphenylmethane polymer represented by the following general formula [1]) and an electrophotographic photosensitive layer (2) made of a resin binder, and the electrophotographic photosensitive layer is removable with a basic liquid, an organic solvent, or a mixed liquid thereof. A method for producing an electrophotographic printing plate comprising the steps of charging a photographic photosensitive layer, imagewise exposing it, developing the toner, and then removing the non-image portion of the electrophotographic photosensitive layer to which toner is not attached.In the above formula, R represents an alkyl group; , nitro group, cyano group or halogen atom, n is 1 to 40
Represents an integer of 0.