JPH02264269A - Plate making device - Google Patents

Abstract

PURPOSE:To easily and speedily obtain a printing original plate by a direct process by using an electrophotographic sensitive body and also a dot image plate for an image of high picture quality by using a silver salt photosensitive material by switching a conveyance path by a switching means and performing wet development and fixation successively at a silver salt photosensitive material processing part. CONSTITUTION:A conveyance guide 54 switches the conveyance path so that a photosensitive material P which is already exposed is conveyed from an exposure part 16 to a toner development part 18 and a photosensitive material A which is already exposed is conveyed to a silver salt photosensitive material processing part 21. Then while the electrophotographic sensitive body is conveyed, electrostatic charging, exposure, development and fixation are carried out continuously to obtain the printing original plate or while the silver salt photosensitive material is conveyed, exposure, development and fixation are carried out continuously to manufacture a film for plate making for printing and paper for plate making. Consequently, when the printing original plate is easily and speedily obtained, the direct process is performed on the electrophotographic sensitive body and when a printing original plate of high picture quality is obtained, the silver salt photosensitive material is used to perform a process on a photographic plate making material such as a PS plate.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a wet plate making apparatus, and in particular, it is capable of performing charging, raster scanning exposure, wet toner development, and fixing while transporting a sheet electrophotographic photoreceptor at a low speed. While continuously performing
The present invention relates to a plate-making apparatus that can continuously perform raster scanning exposure, wet development, and fixing while conveying a sheet-shaped silver salt photosensitive material at a low speed.

<Prior Art> Conventionally, a camera-type electrophotographic device has been used for directly photoengraving a printing original plate from a draft manuscript. FIG. 4 shows a cross-sectional structural view of an example of such an electrophotographic engraving apparatus, for example, the apparatus disclosed in Japanese Patent Application No. 89373/1989 filed by the present applicant.

As shown in the figure, in an electrophotographic engraving apparatus 100, an electrophotographic photoreceptor P is pulled out from a photoreceptor supply section 102 by a pull-out roller 104, uniformly charged by a corona f-electrifier 108, and conveyed by a conveying means. After being cut to length by the cutter 106, it is held at a predetermined position in the photographing unit 110 by suction means or the like.

On the other hand, the draft manuscript S is placed on the manuscript table with its manuscript side facing up.
2 is placed at a predetermined position. Here, when a light source (not shown) emits light for a predetermined period of time, the photographing light irradiated from the light source onto the original g4S is reflected on the surface of the original S, is reflected by the mirror 114 above, and is focused by the lens 116. be illuminated. This focused photographic light is supplied to the photoconductor supply unit 102.
The image is formed on the electrophotographic photoreceptor P that is supplied by the conveyance means and held in the photographing section 110, thereby forming an electrostatic latent image. The photographed photoconductor P is transferred to the developing section 118 by a conveying means.
The electrostatic latent image is developed with toner and transferred to the fixing section 1.
The image is fixed in step 20, and the non-image area is subjected to a hydrophilic treatment in an etching section 122. Thereafter, the photoreceptor P is dried and discharged from the outlet 124 as a printing original plate.

On the other hand, a document image is scanned and exposed to a uniformly charged sheet-like electrophotographic photoreceptor using laser light to form an electrostatic latent image, and then the electrophotographic photoreceptor on which the electrostatic latent image has been formed is exposed. A laser plate making device that develops and fixes toner was published in Japanese Patent Application Laid-Open No. 1986-12.
No. 5371 and No. 62-125372. The plate-making apparatus disclosed herein is an apparatus that continuously performs charging, laser exposure, toner development, and fixing while transporting an electrophotographic photoreceptor using a transport means, and is miniaturized and constitutes the transport means within the apparatus. This is intended to smooth the conveyance of the electrophotographic photoreceptor by the conveyance roller, and also to smoothen the conveyance of the photoreceptor within the toner developing section. The fixed electrophotographic photoreceptor obtained by these apparatuses is subjected to hydrophilic treatment by etching and used as a printing original plate.

On the other hand, in the conventional general photoengraving process, halftone images are created by directly or indirectly exposing the image of the draft manuscript onto a silver halide photosensitive material, and these are used as intermediate media for photolithography such as 25th plate. The original printing plate is obtained by directly exposing the material, printing it, and developing it.

In addition, by processing the image of the draft manuscript and subjecting it to digital indirect exposure using a laser or the like, a direct halftone image plate (such as a plate-making film or plate-making paper for printing) is obtained.
There is also a method of obtaining a printing original plate by printing on a photolithography material such as 25th plate and then developing it.

In such a photolithography process, many scanners and platemaking devices are used.

<Problems to be Solved by the Invention> Incidentally, the electrophotographic printing apparatus disclosed in Japanese Patent Application No. 63-89373 can obtain a printing original plate having a homogeneous image with no unevenness in development density, but one-shot exposure Therefore, it is necessary to have a photographing stand that is at least the size of the largest printing original plate that can be made, which increases the size of the device configuration, and a draft original is always required. That is, even if a complete original for printing is created as a digital image using a computer or the like, if a hard copy is not outputted as a draft manuscript by a printer or the like, the printing master is obtained by this plate-making device. I can't.

By the way, recently, for example, image information input from various media such as computers, graphics, videos, high-definition televisions, CAD/CAM cameras, image information created by plotting machines, etc., images read from manuscripts by scanners, etc. Information, digital image information converted into electrical signals such as character information manually generated from a computerized phototypesetting machine or word processor, and digital image information already stored as a database on an optical disk, CDROM, magnetic disk, magnetic tape, etc. Attempts have been made to create a complete original for printing either by itself or by processing it with various image processing devices such as computers. Further, attempts have been made to directly make a plate from this digital image information, but the above-mentioned plate making apparatus cannot cope with this attempt.

On the other hand, JP-A-62-125371 and JP-A-62-12
The electrophotographic engraving apparatus disclosed in No. 5372 laser-exposes a digital image signal read from a completed manuscript or a digital image signal processed by an image processing device such as a computer and completed as a manuscript onto an electrophotographic photoreceptor for plate making. Charging, laser exposure, toner development, and fixing can be performed continuously, and during these steps, the photoreceptor is conveyed smoothly, but laser exposure allows for higher image quality. No consideration is given to the problems that arise when obtaining a toner image.

In order to obtain high-quality images, it is necessary to increase the scanning line density during laser exposure using the raster scan method. For example, in a normal laser beam printer, 40
It can be said that the image quality is quite high at around 0 dPi, but the original printing plate (
(hereinafter referred to as printing plate), for example, 1000 dP
If it is not higher than i, it cannot be said that the image quality is high.

Generally, in order to obtain a high-quality image of 1000 dpi or more by laser exposure, the sub-scanning speed, that is, the conveyance speed of the photoreceptor becomes slow. For example, the scanning speed in the above-mentioned high-quality laser exposure electrophotographic engraving apparatus depends on the scanning line density, but the low-speed conveyance is 1/25 to 1/4 of the photoreceptor conveyance speed in the one-shot exposure electrophotographic engraving apparatus. becomes. In this case, the image of the document becomes static 1! due to corona charging and laser exposure. There is a problem that the electrostatic (charging) characteristics of the photosensitive surface of the electrophotographic photoreceptor, which is formed as a latent image, changes before it is developed, but conventionally, this problem has been related to image quality. It wasn't given enough consideration.

On the other hand, photoengraving, in which a halftone image plate is created by direct or indirect exposure from the image information of the original or the original, and is printed on a photolithographic material such as a PS plate to obtain a printing original, is based on the above-mentioned sheet-like method. Although this method has the advantage of providing high-quality printing compared to direct plate making on an electrophotographic photoreceptor, it has the problem that the process is complicated and printing plates cannot be easily obtained.

Furthermore, in order to obtain printing original plates of extremely high image quality such as 23rd plate, a plate-making device for making halftone image plates is required;
Even if the image quality is somewhat inferior compared to printing plates, if you want to easily and inexpensively obtain printing plates, you will need a device that directly makes platelets on the electrophotographic photoreceptor, so these two demands are met. There is a problem in that printers such as printers, which usually require a large number of printers, must prepare at least these two devices.

The purpose of the present invention is to solve the problems of the above-mentioned prior art, and
Although the halftone image plate used to obtain extremely high-quality printing plates such as plates is somewhat inferior in image quality compared to 23 plates, etc.
It is an object of the present invention to provide a plate-making device that can produce printing original plates with higher image quality, sufficient toner density, and excellent printing durability than conventional plate-making methods by direct plate-making onto an electrophotographic photoreceptor, using the same device.

Means for Solving the Problems> In order to achieve the above object, the present invention provides an electrophotographic photoreceptor having a photosensitive layer containing a photoconductive substance and a silver salt photosensitive material that are fed to the same scanning conveyance path. a material supply section, a charging section for uniformly charging the electrophotographic photoreceptor, an exposure section for raster scanning exposure of the photoreceptor and the photosensitive material, and a toner for developing the exposed photoreceptor with toner. A developing section, a fixing section that fixes the developed photoconductor, a silver salt-sensitive material processing section that develops and fixes the exposed photosensitive material, and the exposure section electrophotographic photoconductor is transferred from the same scanning conveyance path to the toner phenomenon. and a switching means for switching the conveyance path so that the exposed silver salt photosensitive material is conveyed to the silver salt photosensitive material processing section, and in the case of the electrophotographic photoreceptor, it is charged and exposed while being conveyed. , developing and fixing are continuously performed to make a printing original plate, and in the case of the silver salt photosensitive material, exposure, development and fixing are continuously performed while being transported to produce a printing plate-making film and a plate-making paper. The present invention provides a plate-making device characterized by the following.

The exposure section includes a laser light source and a light deflector, and performs main scanning by deflecting the laser light emitted from the laser light source and carrying a document image in a one-dimensional direction by the light deflector. is preferable.

Further, it is preferable that the exposure section has a movable ND filter that acts on the optical path when exposing the silver salt photosensitive material.

<Operation of the Invention> The plate-making apparatus of the present invention uses a conveyance path with a simple structure that does not deteriorate the charging characteristics of the electrophotographic photoreceptor, and while conveying the electrophotographic photoreceptor in a low-speed sub-scanning manner, the electrophotographic photoreceptor is transported by a corona charger. Uniform charging, laser raster scanning exposure, toner development and fixing are performed continuously, and it is possible to obtain a uniform toner image with sufficient toner density and no density unevenness. It is possible to obtain a printing original plate with higher image quality and superior rigidity than direct plate making on an electrophotographic photoreceptor, and it is also possible to obtain a printing original plate with superior image quality and rigidity. Then, by switching the conveyance path and performing development and fixing continuously, it is possible to obtain a halftone image plate of extremely high image quality.

Therefore, when a user wants to easily and quickly obtain a printing original plate using one plate-making apparatus of the present invention, or when he or she wants to directly make a printing plate on an electrophotographic photoreceptor and obtain a printing original plate with extremely high image quality, the user can:
After producing a halftone image plate using a silver salt photosensitive material, ps
It can be made into photolithography materials such as plates.

<Embodiments> Hereinafter, a plate making apparatus according to the present invention will be described in detail based on preferred embodiments shown in the accompanying drawings.

FIG. 1 is a schematic cross-sectional view showing one embodiment of the plate making apparatus of the present invention.

As shown in the figure, the plate-making apparatus 10 includes a photosensitive material supply section 12 that supplies an electrophotographic photoreceptor P and a silver salt photosensitive material A, a charging section 14 that uniformly charges the photosensitive layer of the photoreceptor P, and a charger 14 that uniformly charges the photosensitive layer of the photoreceptor P. an exposure section 16 that exposes the charged photoreceptor P to laser light in raster scans to form an electrostatic latent image on the photoreceptor P, and exposes the photosensitive material A to laser raster scans to form a latent image or a developed image; , a toner developing section 18 that develops an electrostatic latent image formed on the photosensitive layer of the photoreceptor P using wet toner to form a toner image; A fixing section 20 for fixing, a silver salt-sensitive material processing section 21 for developing and fixing the exposure section photosensitive material A, and an exposure section photoconductor P conveyed from the exposure section 16 to a toner development section 18, and a silver salt photosensitive material processing section 21 for developing and fixing the exposed section photosensitive material A. A conveyance guide 54 is a conveyance path switching means that switches the conveyance path so that the material A is conveyed to the silver salt photosensitive material processing section.
and has.

The electrophotographic photoreceptor P used in the present invention is made of zinc oxide (ZnO) or cadmium sulfide (C), as shown in FIG.
A photosensitive layer P1 containing a photoconductive substance such as dS) dispersed in a binder such as a resin, and a so-called resin dispersion type in which this photosensitive layer P1 is provided on a support P2 whose surface is electrically conductive at least. Any electrophotographic photoreceptor can be used. The support P2 may be any flexible conductive material; for example, it may be a conductive material support made of metal such as aluminum, or the surface of a plastic film, paper, etc. may be made of carbon, metal, etc. It is also possible to use materials treated with electrically conductive substances such as the above and composites of the above-mentioned materials. For example, a paper support treated with conductivity, a paper support treated with conductive waterproofing, a paper support coated or laminated with a conductive polymer on one or both sides, a conductive polymer support, etc. are suitable. The conductive polymer referred to herein may be a polymer that is itself conductive or a polymer containing the above-mentioned conductive substance.

Further, the support P2 may be either a belt-like material or a sheet-like material, but it is more preferably one that can be wound into a roll shape and cut into a sheet shape.

As the photosensitive layer, in addition to the above-mentioned zinc oxide and cadmium sulfide, a photoconductive layer containing an inorganic photoconductive substance such as titanium oxide and amorphous silicon, and a photoconductive layer containing an organic photoconductive substance such as a phthalocyanine compound are used. Furthermore, if necessary, an intermediate layer may be provided between the conductive support and the photoconductive layer, or a backing layer may be provided on the side of the support opposite to the photoconductive layer.

Here, the non-image areas of the photosensitive layer P1 are made hydrophilic by a hydrophilic treatment liquid (for example, an aqueous solution containing a ferrocyanide compound) after the toner is developed and fixed.

A typical example of such an electrophotographic photoreceptor is the electrophotographic master ELP mark, which is a zinc oxide-resin dispersion type.
and the electrophotographic master ELP mark.

As the silver salt photosensitive material A used in the present invention, any material in which a photosensitive silver salt emulsion layer is laminated on a support can be used, but after imagewise exposure, development and fixation are performed to form a halftone image. Any material may be used as long as it can be obtained. For example, lith paper or lith film for obtaining a halftone image plate is used. These light-sensitive materials generally include a support A3, a photosensitive silver salt emulsion layer A2 laminated thereon, and a layer laminated on top of the support A3 to protect the emulsion layer A2, as shown in FIG. Protective layer A1 and support A3
A layer composed of an emulsion layer A2 and a backing layer A4 laminated on the opposite side when viewed from above is used.

The photosensitive silver salt emulsion layer A2 contains photosensitive silver chloride (Ag
Cfi), silver bromide (AgBr), silver iodide (Agl), and composite compounds thereof, etc., and a sensitizing dye, a supersensitizer, and a stabilizer are added to this emulsion. However, a hardening agent, a surfactant, a latex polymer, etc. may be added to the coating.

The support A3 may be anything that can be used as a support for lith paper, lith film, etc., such as a paper support, a paper support laminated with an organic film on both sides, or a transparent organic film support. Organic film materials include polyethylene, polyethylene phthalate (P
ET), cellulose acetate, cellulose triacetate (CTA), polystyrene and polycarbonate.

The uppermost protective layer A1 may contain gelatin as a main component, and may also contain a hardening agent, a surfactant, a matting agent, etc.

The lowermost backing layer A4 may also contain gelatin as a main component, and may further contain a latex polymer, a surfactant, a matting agent, a hardening agent, etc.

Although the protective layer A1 and the backing layer do not need to be provided, it is preferable that they be provided for the purpose of protecting the photosensitive material A, particularly for protecting the photosensitive emulsion layer.

Here, the electrophotographic photoreceptor P and silver salt photosensitive material A used in the present invention may be either a band or a sheet in shape, but more preferably they can be wound into a roll and cut. It is best to use a material that can be made into a sheet.

The photosensitive material supply unit 12 includes a magazine 22 that accommodates therein an electrophotographic photoreceptor P wound into a roll with the photosensitive layer P1 inside, and a magazine 22 which stores an electrophotographic photoreceptor P wound into a roll with the photosensitive emulsion layer A2 inside. Magazine 2 that accommodates the silver salt photosensitive material A inside.
3 is detachably attached to the photoconductor P of the magazine 22.
Three pull-out rollers 24a and 24b correspond to the slit-like opening of the take-out port 22a of the magazine 23, and draw-out rollers 25a,
25b is provided. Each one of the pull-out rollers 2
4a and 25b are configured to be movable between a position separated from the other pull-out roller 24b, 25b, indicated by a dotted line, and a contact position, indicated by a solid line. Here, the pull-out roller 24a is in a separated position shown by the dotted line until the magazine 22 is installed, and the tip of the photoreceptor P protruding from the outlet of the magazine 22 is inserted between the take-out rollers 24a and 24b, and the magazine 22 is installed in the predetermined position,
The photoreceptor P is moved to the position shown by the solid line, and the leading end of the photoreceptor P is securely held between it and the pull-out roller 24b. At this time, it is preferable that the pull-out roller 24a is urged toward the third-out roller 24b by an unillustrated urging means.

The three-output rollers 25a and 25b also have the same structure and function as described above in mounting the magazine 23 and pulling out the photosensitive material A, so a description thereof will be omitted.

Pull-out rollers 24a, 24b and 25a.

A cutter 26 is provided adjacent to the front side of the cutter 25b (here, the downstream side of the conveyance of the photoreceptor P and the photosensitive material A).

In front of the cutter 26, a descending conveyance guide 28 is provided, and further in front of the conveyance guide 28, conveyance rollers 30a and 30b are provided at a predetermined distance from the cutter 26.

The conveyance rollers 30a and 30b are rotationally driven by a drive source such as a motor (not shown) via a clutch. Here, the pull-out roller 24a.

24b, the photoreceptor P is pulled out from the magazine 22 with its photosensitive layer P1 facing downward, or by the pull-out roller 25.
a, 25b, the photosensitive material A has its photosensitive emulsion layer A2.
When the magazine 23 is pulled out from the magazine 23 with the side facing down, and its leading end is sandwiched between the conveyance rollers 30a, 30b, the clutches of the conveyance rollers 30a, 30b are disengaged and their rotation is stopped, but the rotation of the conveyance rollers 30a, 30b is stopped. 25a, 2
5b rotates and continues to pull out the photoreceptor P or photosensitive material A, so that the photoreceptor P or photosensitive material A is stored in a loop shape on the conveyance guide 28. After that, when the photoreceptor P of a predetermined length is pulled out, the pull-out rollers 24a, 24
b or 25a and 25b are stopped, and the cutter 26 cuts the photoreceptor P or the photosensitive material A into a sheet.

A corona charger 32 constituting the charging section 14 is disposed in front of the conveyance rollers 30a, 30b at a predetermined distance.
The sheet-like electrophotographic photoreceptor P conveyed by the conveyance rollers 30a and 30b is uniformly charged.

In the example shown in FIG. 1, the corona charger 32 applies charges only to the surface of the photoreceptor P on the photosensitive layer P1 side, but at this time, the back surface of the photoreceptor P (the surface on the support P2 side) is charged. Unless charges of opposite sign are supplied, the photosensitive layer P1 cannot be charged properly. Therefore, in the illustrated example, the back surface of the photoreceptor P (
The conveying roller 30a that comes into contact with the support P2 side) is made of an electrically conductive material, and the conductivity of the support P2 of the photoreceptor P is used to move the photoreceptor P at a position facing the corona charger 32 and at a position away from the corona charger 32. The surface on the support P2 side is covered with a conductive material, for example, the metal conveyance roller 30.
It is grounded by a. Pressure 11 between the corona charger 32 and the clamping point of the transport rollers 30a and 30b (more precisely, the contact point between the metal!! transport roller 30a and the back surface of the photoreceptor P)
iD is preferably 50 mm or less. Although this distance 111iD is preferably narrow, the surface resistivity of the back surface of the electrophotographic photoreceptor P is a high resistance material of 107 to 10Ω, but the surface resistivity of the photoreceptor P used in the present invention is 5X)09Ω. If the sub-scanning conveyance speed of the photoreceptor P is 25 mm/sec or less, even if the distance is 50 mm, a predetermined amount of charge can be sufficiently charged.

The conductive material constituting the conveyance roller 30a may be any material as long as it has a surface resistivity of 106Ω or less, and for example, metal is preferable. The metal is not particularly limited, but aluminum and the like are preferred. Since one conveyance roller 30b comes into contact with the photosensitive layer P1 of the photoreceptor P, it is preferable to have appropriate softness, and for example, at least the surface is preferably made of carbon-containing acrylonitrile butadiene rubber (NBR). .

In the illustrated example, a single corona type is used in which the corona charger 32 is disposed only on the photosensitive layer P1 side of the electrophotographic photoreceptor P, and the conveyance roller 30a that contacts the support P2 on the back side is a roller made of a conductive material. The present invention is not limited to this, and the conveyance roller 30a is a normal roller, and the conveyance roller 30a is used not only on the photosensitive layer P1 side but also on the back side of the support P2.
A double corona charging method may also be used in which a corona charger is disposed on both sides and corona charging is performed from both sides at the same time. Furthermore, even in the case of a single corona charging method that does not use a corona charger on the back side, the back support P2 of the photoreceptor P is connected to the conductor at a position facing the corona charger 32 that charges the photosensitive layer P1 on the front side. For example, a configuration may be adopted in which a metal electrode, a static eliminating brush, a metal roll, etc. are arranged to provide grounding, thereby improving the corona chargeability of the photosensitive layer P1.

In the present invention, the photosensitive material A is
0b, the corona charger 32 of the charging unit 14 is configured not to operate.

The exposure section 16 wraps the negative-like charged photoreceptor P or photosensitive material A around its surface, and uses a writing drum 34 for sub-scanning conveyance, and limits the exposure position 34a to loosen the photoreceptor P or photosensitive material A. a sub-scanning conveyance means having nip rollers 36 and 38 which are brought into contact with the writing drum 34 without any interference, and a sensitive material detection sensor 4 disposed close to the upstream side of the contact position between the writing drum 34 and the upstream nip roller 36.
Due to the difference in photosensitivity between the photoreceptor P and the photosensitive material A, the light path is changed during laser raster scanning exposure of the photosensitive material A in order to adjust the intensity of the exposure beam. For example, an ND filter 43 inserted into the
An optical modulator 44 such as an OM (acousto-optic modulator) reflects and deflects the intensity-modulated laser light to the writing drum 3.
4 on the exposure position 34a (photoreceptor P
or the conveyance direction of the photosensitive material A), and an optical deflector 46 such as a rotating polygon mirror that performs main scanning in a direction substantially perpendicular to the conveying direction of the photosensitive material A. It is composed of a scanning lens 48 made of a focusing fθ lens or the like, a modulation circuit 50 that drives the optical modulator 44, and a laser exposure means having an image processing device 52 that supplies the original image as an analog image signal.

Here, the nip rollers 36 and 38 are located at a predetermined distance from the writing drum 34 shown by the dotted line until the photoconductor P or photosensitive material A is conveyed, and the photosensitive material detection sensor 40 After a predetermined period of time has elapsed since the leading edge of material A was detected (for example, when the leading edge of photoreceptor P or photosensitive material A is connected to nip rulers 36 and 38 and writing drum 3
4), moves to the position shown by the solid line,
A photoreceptor P or photosensitive material A is placed between the writing drum 34 and the writing drum 34.
The photoreceptor P or the photosensitive material A is brought into contact with the writing drum 34 without any gaps. Further, it is preferable that the nip rollers 36 and 38 be biased toward the writing drum 34 with a predetermined pressing force by biasing means (not shown).

The writing drum 34 is used to write an original image in the main scanning direction using a laser beam.
The laser beam is conveyed at a constant speed in the sub-scanning direction substantially perpendicular to the main-scanning direction, and two-dimensional writing is performed on the photosensitive layer P1 of the photoreceptor P or the photosensitive emulsion layer A2 of the photosensitive material A using laser light. It is best to be driven by a DC motor with rotational precision.

Due to the rotational drive of the writing drum 34, the sub-scanning conveyance speed of the photoreceptor P or the photosensitive material A needs to be slow in order to obtain high image quality. For example, the scan line is 1000 dP
It is preferable to set it to i or more. In this case, the sub-scanning conveyance speed, that is, the conveyance speed of the photoreceptor P or the conveyance speed in the exposure section 16 and the silver salt-sensitive material processing section 21 are the same.
It is preferable to set it to On+m/sec or less. Preferably 25 mm/sec or less, more preferably 10 mm/s
It is better to set it to ec or less. There is no need to set a lower limit, but if it is too slow, it will take too much time to make plates and create halftone negative/positive manuscripts, so 2.5 mra/se.
It may be about c.

The sensitive material detection sensor 40 may be of any type as long as it can detect the arrival of the photoconductor P or the photosensitive material A. For example, it may be composed of a light emitting/receiving element, through which the tip of the photoconductor P or the photosensitive material A passes. An optical sensor or the like that detects by blocking light can be used.

The laser light source 42 is a semiconductor laser (LD), He-Ne
Any laser can be used, such as a laser or a gas laser such as an Ar laser or a CO2 laser, as long as it has an emission wavelength that makes the spectral sensitivity of the photosensitive layer P1 of the photoreceptor P or the photosensitive emulsion layer of the photosensitive material A a predetermined value or more. It is possible and also
A light emitting diode (LED) can also be used if it has a sufficient amount of light.

Since the ND filter 43 is generally lower in exposure sensitivity than the exposure sensitivity of the electrophotographic photoreceptor P and the sensitivity of the silver salt photosensitive material A, the ND filter 43 is emitted from a laser light source 42 adjusted to match the exposure sensitivity of the photoreceptor P. In order to reduce the intensity of the laser light to match the exposure sensitivity of photosensitive material A, the amount of light inserted into the laser beam path is adjusted by moving from the solid line position to the dotted line position in the figure when exposing photosensitive material A. It's a filter. For example, the reduction rate of the beam intensity by inserting the ND filter 43 into the laser light path can be about 1/10.

In the illustrated example, an optical modulator 44 such as an AOM is used to intensity-modulate the laser beam path according to the document image, but it is also possible to directly intensity-modulate the emitted laser beam by modulating the drive circuit of the laser light source. It may be configured as follows. Furthermore, in this case, the ND filter 43 may not be provided either.

The optical deflector 46 is not limited to a polygon mirror, ie, a rotating polygon mirror, but may be any device that can deflect laser light at a predetermined angle in a one-dimensional direction, and a galvanometer or the like may also be used.

The image processing device 52 processes the original image signal, performs image processing as an analog signal or digital signal to suit laser exposure, and finally sends the analog image signal to a modulation circuit 50 that drives the optical modulator 44. There is no particular restriction as long as it can be supplied as

Further, the original original image signal may be an image information signal photoelectrically read from the original, for example, a completed draft manuscript, or may be an image information signal read from a computer, video, television, C
Image information signals input from various media such as AD/CAM cameras, image and character information signals input manually from drawing machines, computer typesetting machines, word processors, scanners, etc., and image and character information signals already converted into electrical signals, optical disks, CD ROMs, magnetic It may be an image information signal stored in a storage medium such as a disk or a magnetic tape as a database, or it may be an image information signal that has been processed by a computer or the like and converted into a manuscript. The image information signal may be an analog signal or a digital signal.

That is, the image processing device 52 referred to here includes a reading device that reads the original document image signal, a computer that processes various image information signals to produce a complete document, and each of the devices described above. The modulation circuit 5 may be connected to these devices and simply receive the original original image signal.
0 as an analog image signal.

Between the exposure section 16, the toner development section 18, and the silver-salt photosensitive material processing section 21, a transport guide 54 which can be rotated and which constitutes the switching means of the present invention is disposed. are arranged at the position indicated by the solid line in the figure to suitably guide the photoreceptor P to the inlet conveyance rollers 56a and 56b of the toner developing section 18, and in the case of the exposed part photosensitive material A, are arranged at the position indicated by the dotted line in the figure. 8
The exposure section photosensitive material A is guided to the entrance conveyance rollers 80a and 80b of the silver salt photosensitive material processing section 21 by moving and switching the conveyance path. This conveyance guide 54 is charged and comes into contact with the surface of the photoreceptor P on the photosensitive layer P1 side, on which an electrostatic latent image is formed, and the protective layer A1, which is the surface of the photosensitive material A on the photosensitive emulsion layer A2 side. It must have both electrical and electrical properties.

The toner developing section 18 includes inlet conveyance rollers 56a and 56b, and an outlet squeeze and conveyance roller 58a.
, 58b, two developing electrodes 62 and 62 forming a jetting nozzle 60 for the liquid toner developer F, and a developing electrode 6262 disposed on the back side of the photoreceptor P, forming a transport path for the photoreceptor P. A back electrode 64, a tank 66 containing liquid toner developer F, and a nozzle 60 for ejecting liquid toner developer F.
and a liquid toner/developer ejecting means 68 for ejecting liquid toner and developer from the developer. When the photoreceptor P is conveyed to the toner developing section 18 with the photosensitive layer P1 facing downward, the charged toner particles in the liquid toner developer F ejected from the ejection nozzle 60 by the ejection means 68 are transferred to the developing electrode 62. Toner development is performed by adhering a predetermined amount to an image area where an electrostatic latent image is formed depending on the electric field strength between the toner 62 and the photosensitive layer P1 of the photoreceptor P.

The liquid toner developer used in the present invention is not particularly limited, and any developer used in conventional wet development can be used. In other words, the liquid toner used in normal wet development generally uses a petroleum-based colorless solvent as a liquid medium to form images using fine organic and inorganic pigments, dyes, etc. classified into the required particle size range. Additives such as particles and charge control agents and dispersion stabilizers are added. When an electrophotographic photoreceptor having an electrostatic latent image is immersed in this,
Coulomb force acts between the electrostatic charge forming the latent image and the charged particles in the liquid toner developer, and the charged particles are electrodeposited onto the latent image and developed.

As such a liquid developer, for example, one in which colored or non-colored polymer or copolymer particles are dispersed in an insulating solvent such as a paraffin solvent (for example, Isopar G, Isopar H) is used. in case of,
A pigment such as carbon black coated with a polymer or copolymer is used. Furthermore, the skin toner developer may contain various additives used in the field, such as a dispersant.

As such a liquid toner developer, for example, a typical toner developer ELP-TL (Fuji Photo Film Co., Ltd.) containing positively charged toner particles in a baraf-in solvent is used.
(manufactured by).

Here, a photosensitive layer P is provided between the developing electrodes 62, 62 and the back electrode 64 in order to reduce toner fog in non-image areas.
A voltage having a polarity opposite to that of the charge 1 may be applied.

The fixing section 20 is developed with toner by the toner developing section 18, and has a conveying roller 58a on its output side.

This is for fixing the toner image on the photoreceptor P from which excess liquid toner developer has been squeezed out by the heater 58b, and is composed of heaters 70 and 72 disposed on both sides of the conveyance path of the photoreceptor P.

The heaters 70 and 72 may be of any type as long as they can dry the photoreceptor P and heat and fix the toner image formed on the photosensitive layer P1 of the photoreceptor P. For example, a lamp heater, a panel heater, or the like can be used. Although the heater 72 does not need to be provided, it is preferable to provide it in order to increase the drying speed and fixing speed.

In front of the fixing section 20, a take-out roller 74a is provided.

74b is provided, and the photoreceptor P on which the toner image is fixed in the fixing section is conveyed by take-out rollers 74a and 74b, and is sent out to a take-out tray 76 that protrudes outside from the main body of the plate-making apparatus 10.

Thereafter, the photoreceptor P having this toner image is subjected to a hydrophilic treatment using an etching liquid to form a printing original plate, that is, a printing plate.

By the way, in the present invention, the member that comes into contact with the photosensitive layer P1 of the electrophotographic photoreceptor P that is charged, that is, the photosensitive layer P1 of the photoreceptor P before the electrophotographic photoreceptor P that is charged in a negative manner is developed with toner. A member in contact with the side surface, e.g.
In the plate making apparatus 10 shown in the figure, nip rollers 36, 38,
The surface resistivity of the conveyance guide 54 and one of the entrance rollers 56b of the toner developing section 18 is preferably 10I0Ω or more. More preferably, it is 1011 or more. The reason for this is that when the surface resistivity is less than 1010Ω, the conveyance speed of the photoreceptor frame is slow, for example, 25 mm/s.
ec or less, the charge forming the electrostatic latent image on the photosensitive layer P1 leaks to these members, so when this electrostatic latent image is developed with toner, the toner image density becomes thinner or the density increases. This is because unevenness may occur, leading to problems such as deterioration in image quality and reduction in printing durability when used as a printing plate.

In the plate-making apparatus 10 of the present invention, pull-out rollers 24a and 24b that pull out the photoreceptor P, and a conveyance roller 30b that conveys the photoreceptor P.
, 56a, 56b.

The rollers 58a, 58b, take-out rollers 74a, 74b, and nip rollers 36, 38 are generally made of carbon-containing acrylonitrile butadiene rubber (NBR). Since carbon is a conductive substance, the surface resistance value of these rollers may be reduced.

Therefore, in the present invention, the photosensitive layer P1 of the charged photoreceptor P
The carbon-containing NBR roller that comes into contact with the roller has a lower carbon content and is used as a high-resistance roller with a surface resistivity of 1010Ω or more.

The material of the roller used in the present invention may be any material as long as it does not damage the photosensitive layer P1 of the photoreceptor P, has appropriate hardness, and has a surface resistivity of 1010Ω or more. Examples include silicone rubber, EPT rubber (ethylene propylene terpolymer (EPM, EPDM) rubber), etc. in addition to the carbon-containing NBR mentioned above.

Further, the conveyance guide 54 may be a metal guide with an insulating sheet having a surface resistivity of 1010 Ω or more attached to the surface. Of course, the guide may be made of the same material as the roller described above.

On the other hand, the silver salt sensitive material processing section 21 includes a silver salt sensitive material processing tank 88 consisting of a developing tank 82, a bleaching/fixing tank 84, and a washing tank 86 and 87, which are continuously provided, and a silver salt processing tank 88 that is filled with the inside of these tanks. A drying device 92 that dries the photosensitive material A that has been developed, bleached, fixed, and washed with a processing solution, conveyance rollers 90a and 90b on the exit side of the processing tank 88, and take-out rollers 93a and 93b on the exit side of the drying device 92. It is configured to be sent out as a halftone image plate to a take-out tray 94 that protrudes from the main body of the plate-making device 10 to the outside.

Since the halftone image plate thus obtained uses a silver salt photosensitive material, an image of extremely high quality is formed, and it can be used as a pre-print as is, or it can be synthesized using an image processing device such as a computer. If the image is a printed image, it may be used as a hard copy of the manuscript, or
Furthermore, these halftone image plates can be printed onto a photolithographic material such as a PS plate to finally form a printing original plate.

Here, the entire silver salt sensitive material processing section 21 is made into a unit,
Or silver salt sensitive material processing tank 88 or silver salt sensitive material processing 4i
188 and the in/out side conveyance rollers 80a, 80b, 90a, 9
0b or a part of the silver salt sensitive material processing section 21 including these may be made detachable as a silver salt processing cartridge. Furthermore, in the example shown in FIG. 1, the developed/fixed photoreceptor P and the developed/fixed photosensitive material A are configured to be delivered to separate trays 76 and 94.
After drying, it may be configured to be sent out to the same tray, or it may be configured to be configured to dry the processed photosensitive material A in the fixing section 20 of the photoreceptor P, and then sent out to the same tray 76.

The processing liquid used here is not particularly limited, but may be appropriately selected depending on the photosensitive material A used. Therefore, the structure may be changed depending on the photosensitive material A, but for example, it may be used as plate-making paper, that is, halftone negative paper or halftone positive paper, or as plate-making film, that is, halftone positive film or halftone negative film. It is preferable that the treatment can be performed using the same treatment liquid. When changing the processing liquid depending on the photosensitive material A, it is preferable to use the silver salt photosensitive material processing section 21 or the processing tank 88 as a cartridge and make it removable.

Further, the plate-making apparatus 10 of the present invention shown in FIG. 1 does not have an etching section for making the non-image area of the developed electrophotographic photoreceptor P hydrophilic, whereas the plate-making apparatus 10 of the present invention shown in FIG. The device may include an etching section, such as an electrophotographic device.

Although the plate-making apparatus according to the present invention is basically configured as described above, the present invention is not limited to this, and various improvements and changes in design can be made without departing from the gist of the present invention. Of course, this is possible.

<Example> The present invention will be specifically explained below based on experimental examples.

However, the present invention is not limited to these experimental examples.

First, a ZnO-resin dispersion type electrophotographic photoreceptor, 7-child Photo Master ELP Mark +1 (manufactured by Fuji Photo Film Co., Ltd.), was used as the electrophotographic photoreceptor P, and a paraffin-based liquid toner developer F was used. Using a toner developer ELP-TL (manufactured by Fuji Photo Film Co., Ltd.) containing positively charged toner particles in a solvent, an electrophotographic photoreceptor P is charged with a corona charger 32 in a plate making apparatus 10 shown in FIG. After electrostatic charging, laser raster scanning exposure, toner development, and fixing were performed continuously. Here, in laser raster scanning exposure, a semiconductor laser with a wavelength of 780 nm has a beam diameter of 1/e.
2 and 30 μm was used.

The photoreceptor P obtained as a result has a conveyance speed of 5 mm/s.
Despite the low speed of ec, there is no decrease in toner density due to charging leakage, uneven density, or fogging in non-image areas, and the toner density is sufficient, making it possible to form images with higher quality than conventional ones. He was a master of electronic photography.

Next, photosensitive material A was produced as follows.

Silver chloroiodobromide emulsion containing 35 mol% silver chloride and 0.2 mol% silver iodide (cubic grains, average grain size 0.3 μm)
) 6 kg of 0.05% solution of the following infrared sensitizing dye A
Sensitization in the infrared region was performed by adding 0 mA.

A゛For supersensitization and stabilization of this emulsion, 4.4'-
Bis-(4,6-dinaphthoxypyrimidin-2-ylamino)-stilbenedisulfonic acid disodium salt 0
．． 70 mfl of 5% methanol solution and 2.5-dimethyl-
90 mfl of 0.5% methanol solution of 3-allyl-benzothiazole iodo salt was added. Further, a hardening agent, a latex polymer surfactant, and an emulsion layer were coated on a transparent film support. The amount of silver coated in the emulsion layer was 3.7 g/m2.

On the upper part of the emulsion layer, 50 mg of a hardening agent, a surfactant for coating properties and charge control, and a PMMA matting agent with an average particle size of 2.3 μm were added in an aqueous gelatin solution as a protective layer.
/m2 was applied. The amount of gelatin in this protective layer was 1.0 g/m'.
On the opposite side of the emulsion layer and protective layer when viewed from the support, dye V below was added to an aqueous gelatin solution to give an optical density of 0.9, and latex polymer surfactant P was added.
A backing layer was applied by adding an MMA matting agent and a hardening agent. The amount of gelatin in this backing layer is 3.9g/
It was mj. Moreover, the dry thickness was 3.0μ.

It has been made possible to switch the conveyance route by working at the same time.

The halftone image plate thus obtained had an image of extremely high quality.

/＼ CJs (CH2) At 4S04, plate-making device 1 shown in Fig. 1 was applied to this silver salt photosensitive material A sample.
Scanning exposure was performed using a semiconductor laser with a wavelength of 780 nm and a beam diameter of 30 μm at 1/e2, and LD835 manufactured by Fuji Photo Film Co., Ltd. was used as a developer in the silver salt sensitive material/A processing section 1. After developing using Fuji Photo Film Co., Ltd. LF308 as a fixer,
Dry.

At this time, the corona charger 32 is not operated, the ND filter 43 is applied to the laser beam emitted from the semiconductor laser light source 42, and the beam intensity is reduced to 1/10, and the conveyance guide 54 is moved to the position shown by the dotted line in the figure. Effects> As described in detail above, according to the present invention, an electrophotographic photoreceptor can be transported in a low-speed sub-scanning direction without deteriorating its charging characteristics during transport, using a simple and compact device configuration, and can be transported in a corona state. By sequentially performing uniform charging with a charger, raster scanning exposure with laser light, and toner development and fixing with a wet toner developer, there is no decrease in toner image density and there is no unevenness compared to conventional electrophotographic toner images. Not only is it possible to obtain a photoreceptor on which a high-quality toner image with sufficient density is formed, but it is also possible to convey the silver halide photographic material in the same apparatus in the same scanning conveyance path in low-speed sub-scanning while using the same laser beam. A halftone image plate having an extremely high quality image can be obtained by performing raster scanning exposure using light, then switching the conveyance path using a switching means, and continuously carrying out wet development and fixing in a silver salt sensitive material processing section.

By subjecting the photoreceptor having the thus obtained electrophotographic toner image to a hydrophilic treatment using an etching liquid, a high-quality printing original plate having a sufficiently thick toner image and excellent printing durability is produced. You can get the version.

Further, by printing a halftone image on a photolithography material such as a PS plate from the halftone image plate obtained by the plate making apparatus of the present invention and processing it, a printing original plate of extremely high image quality can be obtained.

Therefore, according to the plate-making apparatus of the present invention, a printing original plate can be obtained simply and quickly by direct plate-making using an electrophotographic photoreceptor, and a printing plate having an extremely high quality image can be obtained by using a silver salt photosensitive material. A dot image plate can be obtained, and furthermore, a high-quality printing plate can be obtained using this plate.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view of an embodiment of a plate-making apparatus according to the present invention. FIG. 2 is a sectional view showing the structure of an electrophotographic photoreceptor used in the plate making apparatus of the present invention. FIG. 3 is a sectional view showing the structure of a silver salt photosensitive material used in the plate making apparatus of the present invention. FIG. 4 is a schematic cross-sectional view of an embodiment of a conventional electrophotographic engraving apparatus. Explanation of symbols 10... Plate making device, 12. 102... Photoreceptor supply section, 14... Charging section, 16... Exposure section, 18... Toner developing section, 20... Fixing section, 21...Silver salt sensitive material processing section, 22.23...Magazine, 22a, 23a...Ejection port, 24a, 24b, 25a, 25b, 1
0458a, 58b, 90a. 90b... Pull-out roller, 26.106... Cutter, 28... Conveyance guide, 30a, 30b... Conveyance roller, 32a, 108... Corona charger, 34... Writing drum , 34a... Exposure position, 36.38... Nip roller, 40... Sensitive material detection sensor, 42... Laser light source, 43... ND filter, 44... Light modulator, 46... - Light deflector, 48... Scanning lens, 5o... Modulation circuit, 52... Image processing device, 54... Conveyance guide, 56a 56b, 80a, 80b... Entrance side conveyance roller, Output side Conveyance roller, 60... Ejection nozzle, 62.62... Developing electrode, 64... Back electrode, 66... Tank, 68... Ejection means, 70.72... Heater, 74a, 74b , 93a. 93b... Take-out roller, 76.94... Take-out tray, 82... Developing tank, 84... Bleaching/constant tank, 86.87... Washing tank, 88... Silver salt sensitive material Processing tank, 100... Electrophotographic engraving device, 1 1 0... U-keizanbu, 112...
Document table, 114... Mirror 116... Lens, 118... Developing section, 120... Fixing section, 122... Etching section, 124... Output port, A... Silver salt photosensitive material , P... Electrophotographic photoreceptor, S... Draft manuscript FIG, 2 Patent applicant Fuji Photo Film Co., Ltd. 1999 08
Month 09th

Claims (1)

[Claims] (1) A sensitive material supply unit that supplies an electrophotographic photoreceptor having a photosensitive layer containing a photoconductive substance and a silver salt photosensitive material to the same scanning conveyance path, and a charging unit for uniformly charging the electrophotographic photoreceptor. an exposure section for raster scanning exposure of the photoconductor and the photosensitive material; a toner development section for developing toner on the exposed photoconductor; a fixing section for fixing the developed photoconductor; A silver salt photosensitive material processing section develops and fixes the material, and the exposure section electrophotographic photoreceptor is conveyed to the toner development section from the same scanning conveyance path, and the exposure section silver salt photosensitive material is transferred to the silver salt photosensitive material. and a switching means for switching the transport path so as to transport the electrophotographic photoreceptor to the processing section, and in the case of the electrophotographic photoreceptor, charging, exposure, development, and fixing are continuously performed while transporting the printing original plate, and the silver salt is In the case of a photosensitive material, a plate-making apparatus is characterized in that it continuously performs exposure, development, and fixing while conveying it to produce plate-making film and plate-making paper for printing.