JP2003107806A - Production of printing machine plate using electrophotographic printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a printing machine plate using an electrophotographic printing method. SOLUTION: The method for producing the printing machine plate on which a print image is formed includes the steps of: electrifying the surface of a photoreceptor with the same charges; exposing and removing charges on the surface of the photoreceptor except the area in which a print image is to be formed, thereby forming a latent image allowing the charges to remain in only the area where the print image is to be formed; attaching toner to the latent image, the toner being electrified by charges having the polarity opposite to that of the charges of the latent image; forming the print image by transferring the toner attached to the latent image onto the printing plate having on its surface an image formation layer containing no photosensitive substance; and removing areas except the image formation layer in which the print image is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a printing plate using an electrophotographic printing method.

2. Description of the Related Art Generally, printing on a recording medium such as paper, synthetic resin, paper, or ceramic is performed by letterpress, intaglio, planographic printing, screen printing, or the like. When printing on a recording medium using these printing methods, a plate for creating a document such as a sentence, an image, or a pattern and printing based on the document, that is,
A block copy (in this specification, such a block copy is referred to as a “printing plate for printing”) is prepared.

A PS plate is a specific example of the printing plate for printing. This PS plate is obtained by coating a flat plate made of metal, synthetic resin, natural fiber, etc. with a photosensitive layer containing a photosensitive substance. The PS plate is exposed by adhering a negative or a positive in which a sentence or an image is taken to the photosensitive layer thereof. Thereafter, the plate is washed with water, treated with an alkali, or treated with an organic solvent for development, and further subjected to etching treatment to obtain a printing plate for printing.

However, since the PS plate uses an expensive photosensitive substance such as OPC (organic photoconductor) or a photosensitive dye in the photosensitive layer, its production cost is high. Also, PS
The plate uses a solvent when developing its photosensitive layer. Therefore, the photosensitive substance eluted from the photosensitive layer is discarded as it is and is rarely reused. Furthermore, the sensitivity of the photosensitive layer in PS plates is generally low, requiring a large amount of light energy for exposure. Furthermore, for some liquids containing a photosensitive liquid or a developing liquid, waste liquid treatment after use thereof may cause environmental problems.

Another specific example of the printing plate is a printing plate using an electrophotographic printing plate coated with a photosensitive substance. This printing plate is generally manufactured by an electrophotographic printing method using a plate material (OPC coated surface / Al plate material) in which OPC is uniformly dispersed on an anodized aluminum plate. The electrophotographic printing method uses a principle similar to that of a photoconductor drum of a copying machine or the like, charges the photoconductor drum, exposes it, forms a latent image, and forms a toner image. Transfer it to a plate to form an image,
Further, it is a method of fixing the image. The OPC coated surface / Al plate material on which the print image is formed by this method is then treated with an alkali or an acid to obtain a printing plate for printing.

[0006] The printing plate using this electrophotographic printing method has the advantage that it requires less exposure energy because it is more photosensitive than the PS plate. On the other hand, similarly to the PS plate, since expensive OPC is used, there are problems in terms of cost and reuse. In addition, some printing plates have a width of 1 m or more, and an electrophotographic printing process of charging, exposing, and latent image is performed on an electrophotographic printing plate material coated with a photosensitive substance. It may be difficult to stably perform each step of the method. In particular, when developing is performed using a liquid (electrophoresis method), it is difficult to keep the developing distance in the lateral direction of the printing plate constant because the developing portion is in a non-contact state. For this reason, it was often found that the image formation became unstable.

Further, the printing plate for printing is required to have high analysis and high quality of a printed image. To meet this requirement, it is necessary to reduce the thickness of the photosensitive layer. Normally, when the photosensitive layer is laminated as a dry film on a substrate, the film thickness is 100 μm.
It will be about. Further, by directly applying the liquid photosensitive material onto the substrate, it is possible to reduce the thickness of the photosensitive layer. However, when the photosensitive layer becomes thin, the photosensitive layer may be peeled off in the process of manufacturing the printing plate. Therefore, the printing plate material is still required to have a thin photosensitive layer and stable formation.

On the other hand, in JP-A-5-246166 and JP-A-5-254267, an image is formed by using zinc oxide as an inorganic pigment on a master plate having an image receiving layer, and then a non-image portion is desensitized. There has been proposed a method for producing a direct-drawing type lithographic printing plate precursor for producing a printing plate precursor. Further, in Japanese Patent Application Laid-Open No. 8-183265, in the above method,
There has been proposed a method for producing a direct-writing type lithographic printing plate precursor, which can obtain a clear image printed matter without printing stains by using zinc oxide treated with phytic acid.

[0009]

SUMMARY OF THE INVENTION The present inventors have recently formed a printed image on a printing plate material that does not contain a photosensitive substance by an electrophotographic printing method, which is simple, inexpensive, high speed, and excellent in image quality. It was found that a printing plate for printing can be manufactured. The present invention is based on these findings.

Therefore, the present invention makes it possible to effectively use a photosensitive substance and thin the printing plate material, and to produce a printing plate for printing which is rapid and has excellent image quality. It is an object of the present invention to provide a method for producing a printing plate using a photographic printing method.

According to the first aspect of the present invention, it is possible to provide a method for manufacturing a printing plate on which a printed image is formed, which method charges the surface of the photoreceptor with the same electric charge. Then, on the surface of the photoconductor, charges other than those on which the print image is formed are exposed and removed to form a latent image in which charges are left only on the part on which the print image is formed. Toner charged with a charge having a polarity opposite to that of the image is attached, and the toner attached to the latent image is transferred to a printing plate material having an image forming layer containing no photosensitive substance on its surface. To form a print image, and remove a portion other than the image forming layer on which the print image is formed.

According to the second aspect of the present invention,
It is possible to provide another method for producing a printing plate for printing on which a print image is formed. The production method exposes and removes electric charges in a portion of the photoreceptor surface where a print image is formed, and prints. A latent image is formed by removing the electric charge only from the image forming portion, and the latent image is charged with toner charged with the same polarity as the electric charge charged on the surface of the photoconductor, and then attached to the latent image. The formed toner is transferred to a printing plate material having an image forming layer containing no photosensitive substance on its surface to form a printed image, and a portion other than the image forming layer on which the printed image is formed. Is included.

Since the manufacturing method according to the present invention uses the printing plate material containing no photosensitive substance, it is possible to avoid wasteful use of the expensive photosensitive substance. Further, the printing plate material can be thinned, and high analysis and high quality of the printed image can be realized. Further, since the printed image is formed by using the electrophotographic printing method, there is an advantage that the printing plate for printing can be manufactured with high sensitivity and at high speed.

[Detailed Description of the Invention]

1. First Aspect of the Present Invention A first aspect of the present invention provides a method for producing a printing plate for printing using the “electrophotographic printing method by normal development”. Regarding the first aspect of the present invention, FIG.
Will be described. FIG. 1-1 shows a specific example of the manufacturing method according to the present invention including the steps of charging, exposing, developing, transferring and removing.

The photosensitive drum 1 is a drum rotatable in the direction of the arrow (clockwise) shown in FIG. The photoconductor drum 1 is rotated clockwise and introduced into the charger 2.
The charger 2 uniformly charges the surface of the photoconductor drum 1 with positive charge (charging step). Next, the photosensitive drum 1 having a positive charge is introduced into the exposure device 3. The exposure device 3 exposes the surface of the photosensitive drum 1 to a portion other than a portion where a print image is formed. As a result, the positive charge in the light-irradiated portion is removed, and a latent image in which the positive charge exists only in the portion forming the print image is formed (exposure step). The latent image having a positive charge is introduced into the developing device 4 by the rotation of the photosensitive drum 1. The developing device 4 attaches the negatively charged toner to the positive charge of the latent image (developing step). Thereafter, this toner is transferred by the rotation of the photosensitive drum 1 to the printing plate material 5 for printing carried in from the direction of the right-hand arrow in FIG. 1-1 to form a printed image (transfer step). The printing plate material 5 on which the print image is formed is sent to the remover 8 and the image forming layer other than the print image is removed (removal step). This produces a printing plate.

The contents of the exposure step and the development step will be described in detail with reference to FIGS. 1-2 and 1-3. The photosensitive drum 1 having a uniform positive charge is carried into the exposure device 3. The exposure device 3 irradiates the developing film 21 (positive type film) with light.
The irradiation light passes through a portion other than the print image portion (hatched portion) and exposes the surface of the photosensitive drum 1. On the surface of the photosensitive drum 1, the positive charge is removed from the part other than the part where the printed image is formed, and a latent image having a positive charge is formed. This completes the exposure process. Next, the photosensitive drum 1 having a latent image with a positive charge is introduced into the developing device 4 through the exposure process described in FIG. The developing device 4 attaches toner having a negative charge to the latent image to develop the latent image.
This completes the developing process. The electrophotographic printing method using the method described with reference to FIGS. 1-2 and 1-3 is called “electrophotographic printing method by normal development”.

Charging Step In the charging step, the surface of the photoconductor is charged with the same electric charge by a charger or the like. Specific examples of the charger include a non-contact charging method such as corona charging and a contact charging method such as roll charging and brush charging. The charging time, applied voltage, etc.
It can be appropriately determined depending on the material of the photoconductor, the form of the printed image, and the like. Examples of the photosensitive material that constitutes the photoconductor include selenium-based, OPC-based, and amorphous silicon-based materials, and the amorphous silicon-based photosensitive material is preferable in terms of speeding up and long life.

Exposure Step In the exposure step, the surface of the photoconductor charged with an electric charge is exposed by an exposure device or the like, and the electric charge other than the portion forming the print image is removed to form a latent image. Specific examples of the light source of the exposure device include a semiconductor laser optical system, an LED optical system, and a liquid crystal shutter (LCS) optical system. Further, the exposure device is configured by combining these light sources, a lens, a mirror and the like. The light source, wavelength, and intensity of exposure can be appropriately determined according to the material of the photoconductor, the type of image to be printed, and the like.

Developing Step In the developing step, a toner charged with a charge having a polarity opposite to that of the latent image is attached to the latent image by a developing device or the like.
The developing device is composed of a mechanism for charging the toner particles, transporting the toner to the developing area, and adhering the toner to the latent image. Examples of the method of charging the toner particles include a method using friction, charge injection, electrophoresis and the like. Examples of the method of transporting toner to the developing area include methods using electrostatic force, gravity, magnetic force, liquid flow, and the like. Then, as a method of combining the charging and the transportation of the toner to attach the toner to the latent image, there are a dry developing method and a wet developing method. Specific examples of the dry developing method include a cascade developing method using gravity, a two-component porcelain brush developing method using magnetic force, a one-component conductive toner developing method, and a one-component insulating toner developing method using electrostatic force. Further, as a specific example of the wet development method, an electrophoresis method using an insulating liquid can be mentioned.

The toner in the present invention is made of a resin or a polymer and has a role of forming a print image on a printing plate for printing. Therefore, the toner is required not to be removed in the removing step of the present invention. For example, when the removing step dissolves the image forming layer on which the printed image is not formed by a solvent such as alkaline or acidic, it is preferable that the image forming layer is not dissolved in these solvents.

Specific examples of the resin or polymer insoluble in the alkaline solvent include polyester, styrene-acrylic acid type resin, polycarbonate, polyvinyl acetate and the like. Specific examples of the resin or polymer insoluble in the acidic solvent include polyacetal and nylon (polyamide resin). Specific examples of the resin or polymer insoluble in the water-soluble organic solvent include polyvinyl alcohol, polyacrylic acid, sodium polyacrylate and the like. The toner may be filled in the developing device or may be introduced into the developing device from an external device. Toner discharge amount,
The ejection time and the like can be appropriately determined.

Transfer Step In the transfer step, the toner adhered to the latent image is transferred to a printing plate material having an image forming layer containing no photosensitive substance on its surface to form a printed image. To be done. As a specific example of the transfer, as shown in FIG. 1-1, the photosensitive drum 1 to which toner is adhered, which is rotated clockwise, and the printing plate material 5 carried in from the right side of this figure are included. Contact is mentioned.

According to a preferred embodiment of the present invention, the toner adhering to the latent image is transferred to the printing plate material to form a printed image, or before or at that time, the front surface or the back surface of the printing plate material is charged. It is preferable to charge an electric charge having a polarity opposite to the electric charge of the applied toner. Such means is, for example, shown in FIG.
The charging device 6 described in 1. can be used. The charging method, charger, etc. may be the same as those described in the charging step.

According to another preferred embodiment of the present invention, the toner adhered to the latent image is transferred onto a printing plate material to form a printed image, or thereafter, by a physical or chemical method. It is preferable to improve the fixability of the toner image. Examples of such physical and chemical methods include electrostatic force, magnetic force, light force, pressurization, heating, melting, and adhesive force. Specific examples of such a method for improving the fixing property include electrostatic transfer (corona charging method, roll charging method, belt charging method), pressure transfer method, heat transfer method, and adhesive transfer method (viscous intermediate material). Method of transferring with intervening),
An exposure transfer method and the like can be mentioned. Such means, for example,
It can be performed by the fixing device 7 described in FIG. The conditions such as charging, heating, and pressure may be appropriately determined according to the photoconductor, printing plate material, toner, and the like.

Removing Step In the removing step, a portion other than the image forming layer on which the printed image is formed is removed by a remover or the like. The removing step may be performed by, for example, the remover 8 illustrated in FIG. As a removing method, a physical or chemical method can be used. Specific examples of such a method include excision of a portion other than the image forming layer and dissolution with a solvent. When a solvent is used, the solvent is required to dissolve only the image forming layer without dissolving the toner. That is, the solvent is required to have a property of dissolving the image forming layer, although it does not dissolve the toner-attached portion on which the printed image is formed. Such a solvent can be appropriately determined depending on the component forming the image forming layer and the component forming the toner. Specific examples of the solvent include an alkaline solvent, an acidic solvent, a water-soluble organic solvent, or a mixture thereof.

Specific examples of the alkaline solvent include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide; alkaline earth metal hydroxides such as magnesium hydroxide and barium hydroxide; sodium carbonate; Ammonium carbonate, sodium phosphate, etc .; ammonia; amine, etc. may be mentioned. Specific examples of the acidic solvent include strong acids and weak acids, and examples thereof include hydrochloric acid, nitric acid, acetic acid, phosphoric acid, and the like. Furthermore, specific examples of the water-soluble organic solvent include lower alcohols such as methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, sec-butanol, tert-butanol, and is.
Examples include o-butanol and n-pentanol.

In the present invention, a cleaning solvent such as water or a water-soluble organic solvent may be used in addition to the above-mentioned solvent for the purpose of further removing the dissolved image forming layer.
According to a preferred aspect of the present invention, this removing step is preferably performed by discharging the above-mentioned solvent by an inkjet recording method.

Arbitrary Step The production method according to the present invention may further include a charge eliminating step and a washing step as optional steps. The charge removal step is to remove the charge of the toner particles not formed on the printing plate material. Specific examples of the static elimination method include exposure and discharge. The static elimination process will be described with reference to FIG. The toner having a negative charge remaining on the surface of the photoconductor drum 1 moves to the charge eliminator 9 as the photoconductor drum 1 rotates. The static eliminator 9 irradiates the photosensitive drum 1 with light to remove negative charges from the toner particles. The cleaning process will be described with reference to FIG. The toner removed in the charge removing step is removed by the cleaner 10.

According to a preferred embodiment of the present invention, it is preferable that the static elimination step and the washing step are performed simultaneously. Specific examples of the device having a charge removing and cleaning function include a magnetic brush cleaner, an electrostatic brush cleaner, a magnetic roller cleaner, and an electrostatic roller cleaner. Further, specific examples of the cleaner device include a blade cleaner, a brush cleaner, and a web cleaner.

Printing Plate Material The production method according to the present invention uses a printing plate material having a substrate and an image forming layer containing no photosensitive substance on its surface.

1) Substrate Specific examples of the substrate include, for example, aluminum, zinc,
Metals such as magnesium, still, copper, chromium, nickel, iron, or alloys of two or more kinds of these; synthetic resins such as nylon and polyester; natural fibers such as silk, cotton, paper; and the like. Among these, metal is preferable for reasons of printing durability, heat resistance, size stability and the like, and synthetic fiber is preferable for convenience of use.

The surface of the metal substrate may be conspicuously treated with an abrasive or a polishing machine, or an oxide film treatment may be performed by anodizing treatment. Further, the surface of the metal substrate may be treated with a surface-adjusting agent such as an acid; an antioxidant such as Kronak solution or Brunak solution; a desensitizing agent for the purpose of pre-etching treatment. In the present invention,
An aluminum plate whose surface is subjected to an oxide film treatment (aluminum oxide coating) is preferred. The thickness of the substrate is for printing purposes,
Although it can be appropriately determined according to the printing device, etc., it is generally about 0.1 to 5 μm, preferably 0.1 to 5 μm.
It is about 1.5 μm.

2) Image Forming Layer In the present invention, an image forming layer that does not contain any photosensitive substance is used. The image forming layer may be made of resin, polymer or the like. When the image forming layer is dissolved in a solvent in the removing step, it is preferably dissolved in the solvent. When the solvent is alkaline, an alkali-soluble resin or polymer is used. When the solvent is acidic, an acid-soluble resin or polymer is used. Further, when the solvent is a water-soluble organic solvent, a resin or polymer soluble in the water-soluble organic solvent is used.

Specific examples of the alkali-soluble resin or polymer include polyvinyl alcohol, polyamide resin, alginic acid-based resin, and the like. Specific examples of the acid-soluble resin or polymer include polyacetal, nylon (polyamide resin), etc. Is mentioned. Specific examples of the water-soluble organic solvent-soluble resin or polymer include polyvinyl alcohol, polyacrylic acid, sodium polyacrylate and the like.

The thickness of the image forming layer can be appropriately determined according to the purpose of printing, the printing apparatus, etc., but is generally 10
It is about 200 μm. According to a preferred embodiment of the present invention, the thickness of the image forming layer can be a thin film of 20 μm or less. The image forming layer according to the present invention need not have a function as a photoreceptor. Therefore, it is possible to make the film thinner than the thickness of the image forming layer in the PS plate (about 30 to 100 μm) and the thickness of the image forming layer in the electrophotographic printing photoreceptor (exceeding 20 μm). The resin or polymer forming the image forming layer preferably has a volume resistivity of 10 ⁹ Ωcm or more. The image forming layer according to the present invention is composed of the above-mentioned resin or polymer, but a colorant, particularly carbon black, may be added for the purpose of adjusting the volume resistivity thereof.

Specific examples of the method of applying the image forming layer to the substrate include coating, impregnation, dipping and the like. It is preferable that the image forming layer preparation liquid is applied by a coating machine having a coater head. The coater head consists of coating liquid, base material,
It can be appropriately selected and selected according to the printing plate material to be produced. Examples of coater heads include blade coaters, air knife coaters, gravure coaters, transfer roll coaters (KCM coaters, gate roll coaters, etc.), lot coaters, bar coaters, hydrobar coaters, die coaters, bead coaters, curtain coaters, and the like. Then, after that, the printing plate material can be obtained by drying.

2. Production Method According to Second Aspect The second aspect of the present invention provides a method for producing a printing plate using the “electrophotographic printing method by reversal development”. The second aspect of the present invention, like the first aspect of the present invention, is an invention comprising the steps of charging, exposing, developing, transferring and removing. However, the second aspect of the present invention is different from the first aspect of the present invention in the exposure step and the developing step.

Regarding the second aspect of the present invention, FIG.
This will be described with reference to FIGS. FIG. 2-1 illustrates a specific example of the manufacturing method according to the second aspect of the present invention. The photoconductor drum 1 is a drum that can rotate in the arrow direction (clockwise direction) shown in FIG. The photosensitive drum 1 rotates clockwise and is introduced into the charger 2. The charger 2 is
The surface of the photoconductor drum 1 is uniformly charged with positive charge (charging step). Next, the photoconductor drum 1 having a positive charge
Are introduced into the exposure device 3. The exposure unit 3 exposes the surface of the photoconductor drum 1 to light to form a print image, removes positive charges from the exposed portion, and charges only the portion to form a print image. To form a latent image (exposure step). The latent image from which the charges have been removed is introduced into the developing device 4 by the rotation of the photosensitive drum 1. Developing device 4
Attaches to the latent image a toner charged with a charge having the same polarity as the positive charge charged on the surface of the photoconductor (developing step). Then, the toner image is transferred by the rotation of the photosensitive drum 1 to the printing plate material 5 for printing carried in from the right-hand direction arrow in FIG. The printing material 5 on which the print image is formed is sent to the remover 8 and the portion other than the print image is removed (removal step). As a result, a printing plate is produced.

The contents of the exposure process and the development process will be described in detail with reference to FIGS. 2-2 and 2-3. The photoconductor drum 1 having a uniform positive charge is introduced into the exposure device 3. The exposure device 3 irradiates the developing film 31 (negative film) with light. The irradiation light passes through the printed image portion (hatched portion) to expose the surface of the photosensitive drum 1. On the surface of the photosensitive drum 1,
The positive charge in the portion forming the print image is removed, and a latent image having no charge is formed. This completes the exposure process. Next, through the exposure process described in FIG. 2B, the photosensitive drum 1 having an uncharged latent image.
Are introduced into the developing device 4. The developing device 4 develops the latent image by attaching a toner having a positive charge having the same polarity as the positive charge that charges the surface of the photoreceptor. This completes the developing process. The electrophotographic printing using the method described with reference to FIGS. 2-2 and 2-3 is called an “electrophotographic printing method by reversal development”.

In the second aspect of the present invention, the charging step, the removing step, the transferring step, the optional step, and the printing plate material may be the same as those in the first aspect of the present invention. The exposure step and the development step in the second aspect of the present invention will be described below.

Exposure Step In the exposure step, the surface of the charged photoreceptor is exposed to remove the electric charge in the portion where the print image is formed, and the latent image in which the electric charge is removed only in the portion where the print image is formed is formed. Form.
Regarding the other exposure steps and exposure methods,
It may be similar to the first aspect of the present invention.

Developing Step In the developing step, the latent image is charged with toner charged with the same charge as the charge on the surface of the photoreceptor. According to a preferred embodiment of the present invention, when a toner charged with a charge having the same polarity as the charge on the surface of the photoreceptor is attached to the latent image, the charged toner on the surface or the back surface of the photoreceptor is It is preferable to charge a charge having a polarity opposite to that of the charge.
The charging may be performed by a charging device provided inside the developing device or a charging device separately provided. The charger and charging method may be the same as those described in the first aspect of the present invention. The development process and the development method other than this may be the same as those in the first aspect of the present invention.

3. Use of printing plate The printing plate produced by the production method according to the present invention can be used as various printing plates. In particular, it is preferably used for letterpress printing, intaglio printing, lithographic printing, or screen printing. The printing plate produced by the present invention can be used for letterpress printing, intaglio printing, lithographic printing, or screen printing to produce a printed matter. The printed image of the printing plate may be either a real image or a mirror image.

[Brief description of drawings]

FIG. 1 shows an example of a method for manufacturing a printing plate using a “electrophotographic printing method by normal development”, which is the first embodiment of the present invention. 1-2 show the exposure step of the manufacturing method according to the first aspect of the present invention. 1 to 3 show the developing process of the manufacturing method according to the first aspect of the present invention.

FIG. 2A shows an example of a method for manufacturing a printing plate using a “electrophotographic printing method by reversal phenomenon”, which is the second embodiment of the present invention. 2-2 shows the exposure step of the manufacturing method according to the first aspect of the present invention. FIGS. 2-3 show the developing process of the manufacturing method according to the first aspect of the present invention.

Continued front page    F-term (reference) 2H070 DD01 EE01 EE02 EE03 EE06                       EE07 EE13 FF02 FF07                 2H084 AA19 AA31 AA32 AE03 BB02                       BB04 BB07 BB13 CC01 CC03                       CC05 CC10                 2H114 AA01 AA02 AA04 AB01 BA03                       DA50 DA51 DA56 DA57 DA61                       EA01 EA02 GA03 GA06 GA09                       GA34 GA36                 2H170 DD01 EE01 EE02 EE03 EE06                       EE07 EE13 FF02 FF07

Claims (14)

[Claims] 1. A surface of a photoconductor is charged with the same electric charge, and charges on the surface of the photoconductor other than a part where a print image is formed are exposed to be removed to leave a charge only in a part where a print image is formed. To form a latent image, and a toner charged with a charge having a polarity opposite to that of the latent image is attached to the latent image, and the toner attached to the latent image is formed into an image forming layer containing no photosensitive substance. To form a print image by transferring to a printing plate material having the surface, and removing a portion other than the image forming layer on which the print image is formed, a print image is formed. For producing the printed printing plate. 2. The toner for printing, which is attached to the latent image, is transferred to a printing plate material having an image forming layer containing no photosensitive substance on its surface to form a printed image, or before the printing image is formed. The manufacturing method according to claim 1, further comprising charging the surface or the back surface of the plate material with a charge having a polarity opposite to that of the charge with which the toner is charged. 3. The electrostatic force or magnetic force is applied when the toner adhering to the latent image is transferred to a printing plate material having an image forming layer containing no photosensitive substance on its surface to form a printed image, or thereafter. The manufacturing method according to claim 1 or 2, further comprising fixing the toner to the printing plate material with light, pressure, heating, melting, or adhesive force. 4. A latent image obtained by exposing a surface of a photoconductor to the same electric charge, exposing and removing the electric charge of a portion forming a print image on the surface of the photoconductor, and removing the electric charge of only a portion forming a print image. An image is formed, and a toner charged with a charge having the same polarity as the charge on the surface of the photoconductor is attached to the latent image, and the toner attached to the latent image is formed into an image containing no photosensitive substance. A printed image, which comprises transferring a layer to a printing plate material having a surface to form a printed image, and removing a portion other than the image forming layer on which the printed image is formed, A method for manufacturing the formed printing plate. 5. When the toner charged with a charge having the same polarity as the charge on the surface of the photoreceptor is attached to the latent image, the charge on the surface or the back of the photoreceptor is charged with the toner. The manufacturing method according to claim 4, further comprising charging with an electric charge having a polarity opposite to that of. 6. The printing method according to claim 1, wherein the toner attached to the latent image is transferred to a printing plate material having an image forming layer containing no photosensitive substance on its surface to form a printed image, or before the printing image is formed. The manufacturing method according to claim 4, further comprising charging the surface or the back surface of the plate material with an electric charge having a polarity opposite to that of the electric charge charged by the toner. 7. The electrostatic force or magnetic force is applied when the toner attached to the latent image is transferred to a printing plate material having an image forming layer containing no photosensitive substance on its surface to form a printed image, or thereafter. 7. The manufacturing method according to claim 4, further comprising fixing the toner to the printing plate material with light, pressure, heating, melting, or adhesive force. 8. The production according to claim 1, wherein the removal of the portion other than the image forming layer on which the printed image is formed is a dissolution with an alkaline or acidic solvent. Method. 9. The manufacturing method according to claim 8, wherein the toner forming the printed image is one that does not dissolve in an alkaline or acidic solvent. 10. The printing plate material according to claim 1, comprising an aluminum substrate having an aluminum oxide coating layer and an image forming layer containing no photosensitive substance thereon. The method according to item 1. 11. The manufacturing method according to claim 10, wherein the image forming layer is made of a resin or polymer soluble in an alkaline or acidic solvent. 12. The printed image is a real image or a mirror image,
The manufacturing method according to claim 1. 13. A printing plate for printing manufactured by the manufacturing method according to claim 1. 14. The printing plate according to claim 13, which is used for letterpress printing, intaglio printing, lithographic printing, or screen printing.