JP2005266065A - Processing apparatus for planographic printing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a processing apparatus for a planographic printing plate to prevent image irregularity due to liquid dropping which is not caused by an AM screen but first caused by high definition exposure. <P>SOLUTION: In the processing apparatus to subject a planographic printing plate having a photosensitive material applied thereon for forming an image by use of an FM screen or a high-definition AM screen to successively at least a developing process and a washing process, the apparatus is provided with a liquid draining brush 69 as a liquid draining member so as to scrape off the liquid on the lower roller 62B of a pair of entrance rollers 62 at the entrance of the washing process. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a processing device for a lithographic printing plate on which an image is formed on a high-definition AM screen or FM screen among processing devices for a lithographic printing plate. In particular, the present invention relates to an apparatus for processing a lithographic printing plate having a photothermal conversion agent in the lithographic printing plate and performing laser exposure in a heat mode.

  In general, a photosensitive lithographic printing plate is developed by a photosensitive lithographic processing apparatus (hereinafter referred to as a printing plate processor). In this printing plate processor, the development processing is performed by immersing the photosensitive lithographic printing plate on which an image is recorded in a developing solution while transporting the image in the developing vessel, such as a rotating brush roller provided in the developing solution. The rubbing means is used to remove the photosensitive layer corresponding to the non-image forming area of the photosensitive lithographic printing plate. In this printing plate processor, a photosensitive lithographic printing plate that has been processed with a developer is washed with washing water in a washing section (washing treatment) and then insensitive by applying a gum solution in a desensitizing section. An oiling treatment is performed. Here, the water washing section is composed of an inlet / outlet roller and a spray pipe, and the washing of the planographic printing plate is performed by discharging washing water from the spray pipe onto the planographic printing plate after passing through the inlet roller.

In recent years, in plate making systems such as thermal plates, the trend toward higher definition of output images has progressed, and in AM screens, high-definition images with a large number of dotted lines and image patterns with a minimum pixel size such as FM screens have been introduced to the market. It has come to be.
Until now, negative and positive printing plates have been mainly used as photosensitive lithographic printing plates, but with the recent CTP conversion, systems using photopolymer plates and thermal plates are often used. It has become. In particular, the progress of the thermal plate exposed in the heat mode is remarkable.

JP 2003-5379 A JP 2003-107684 A

However, the washing water discharged from the washing part spray pipe hits the upper and lower rollers of the washing inlet and wraps around the developing part while adhering to the rollers, and the washing water is stored on the meniscus part developing part side of the inlet roller. When a lithographic printing plate was brought in from the developing unit, washing water was sometimes taken out on the plate, resulting in liquid dripping.
It is known that a liquid draining member is usually provided in the upper roller of the water washing section in order to remove the liquid that flows around, for example, a metal bar. However, the lower roller has not had a liquid draining member so far, and the flow of the cleaning liquid from the lower roller has had a great influence on the liquid dripping.

  On the other hand, on the planographic printing plate, development proceeds slightly until it is conveyed to the water washing section, regardless of whether the developer is squeezed by the squeezing roller at the exit of the developing section. When dripping occurs on the planographic printing plate from the washing section entrance roller to the developing section side, development that has progressed slightly in the dripping section is suppressed. As a result, the dripping portion has a density different from that of the surroundings, and image unevenness occurs. For example, when a positive plate is used, the concentration of the dripping portion increases. Further, in the case of a high-definition AM screen image and FM screen image having a large image portion circumference, the density change due to the development progress is large, so the degree of image unevenness deteriorates.

In particular, in the thermal plate, the halftone dot area is likely to change depending on the degree of progress of development, so it is important to perform uniform development processing. Therefore, the above-described image unevenness is likely to occur, and a countermeasure is required.
SUMMARY OF THE INVENTION An object of the present invention is to prevent image unevenness due to dripping from a water washing section, which occurs in a development system aimed at uniform development processing.

  In order to achieve the above object, the invention of the lithographic printing plate processing apparatus according to claim 1 is characterized in that at least a lithographic printing plate coated with a photosensitive material for forming an image on an FM screen or a high-definition AM screen is developed and washed with water. In the processing apparatus having in order, the washing process inlet has a pair of inlet rollers for sandwiching and transporting the printing plate, and a liquid draining member for scraping the liquid is provided on the lower rollers of the pair of inlet rollers. It is characterized by that.

According to a second aspect of the present invention, in the lithographic printing plate processing apparatus according to the first aspect, the liquid scraping member is a liquid draining brush that scrapes off the liquid on the lower roller.
According to a third aspect of the present invention, in the lithographic printing plate processing apparatus according to the first aspect, the liquid scraping member is a liquid draining rod that scrapes off the liquid on the lower roller.
According to a fourth aspect of the present invention, in the lithographic printing plate processing apparatus according to the first aspect, the liquid cutting member is a liquid draining blade that scrapes off the liquid on the lower roller. Printing plate processing device.
A fifth aspect of the present invention is the lithographic printing plate processing apparatus according to any one of the first to fourth aspects, wherein the lithographic printing plate contains a photothermal conversion agent and is exposed in a heat mode by a laser. And
The invention of the lithographic printing plate processing method according to claim 6 is a high-definition AM screen having 250 lines or more or a high-definition FM screen having a minimum pixel size of 50 μm or less constituting a halftone dot. A lithographic printing plate processing method comprising: exposing a lithographic printing plate to a laser by exposure, transporting and developing the lithographic printing plate while immersing the lithographic printing plate in a developer, washing with water, and finishing; The lithographic printing plate discharged from the exit roller is scraped off the liquid of the lower roller of the pair of entrance rollers before the pair of entrance rollers at the entrance of the washing process sandwich and convey the planographic printing plate.

  As described above, according to the present invention, the lower roller of the washing unit inlet roller pair of the printing plate processor is drained to prevent dripping from the washing unit inlet roller onto the plate. It is possible to prevent image unevenness that is a problem during image plate making. With this liquid cutting, the printing plate processor can perform processing without causing image unevenness of the planographic printing plate.

Hereinafter, embodiments of the invention will be described in detail.
The present invention relates to a development processing apparatus for a lithographic printing plate coated with a photosensitive material, and relates to a processing apparatus for a lithographic printing plate on which image exposure is performed with a high-definition AM screen or FM screen. In particular, the lithographic printing plate has a photothermal conversion agent and is highly effective in lithographic printing plate processing in which laser exposure is performed in a heat mode. The present invention is characterized by preventing image unevenness due to liquid dripping from the water washing section.

An example of the first embodiment of the present invention is shown in FIG.
A printing plate processor 10 shown in FIG. 1 develops a photosensitive lithographic printing plate that has been exposed on a high-definition AM screen, FM screen, or hybrid screen by an exposure device (not shown). Here, the exposure apparatus differs depending on the system. In the case of the CTP plate making system, the image data is directly exposed to the photosensitive planographic printing plate without using a medium by using a semiconductor laser, a gas laser, a solid laser or the like. Prior to exposure, RIP processing is performed to form an image pattern necessary for exposure. Here, an AM screen or FM screen having 250 lines or more, or a hybrid screen having both of them may be used for the image pattern. In particular, FM screens and hybrid screens have been rapidly introduced into the market in recent years. For example, in the FM screen, CREO staccato10, 20, 25, 35, and 36 are frequently used, Dainippon Screen Randot, RandotX (X = 10,15,20), Heidelbelg Stainscreening, Agfa CristalRaster has been applied to the market. On the other hand, for hybrid screens, Dainippon Screen's Fairdot and Agfa's Sublima are used in the market. In addition to conventional screens, AM screens that support high definition, such as Co-Re SCREEN manufactured by Fuji Film, are also applied.

  The printing plate processor 10 generally has a developing unit for processing a photosensitive lithographic printing plate with a developer, a washing unit for washing with water, and a finisher for applying a gum solution to the lithographic printing plate after washing to desensitize the plate. A drying section is provided for drying the lithographic printing plate coming out from the section and the finisher section. The present invention is not limited to the above general structure, and can be applied as long as it has at least a development processing mechanism of a developing unit and a washing unit.

  The printing plate processor 10 includes a developing unit 14 for processing the printing plate 12 with a developing solution, a rinsing unit 16 for brushing the plate surface while washing the printing plate 12 processed with the developing solution while supplying rinsing water, A finishing processing unit 18 for applying a gum solution for protecting the plate surface to the subsequent printing plate 12 to desensitize it and a drying unit 20 for drying the printing plate 12 are provided. That is, in the printing plate processor, a developing process, a washing process, a finishing process, and a drying process are sequentially arranged along the direction of conveyance of the printing plate 12 (arrow A in FIG. 1).

  A processing tank 22 is provided in the printing plate processor 10. In this processing tank 22, a developing tank 24 is formed at a position that becomes the developing section 14 as a processing tank, and a washing tank 26 and a finishing processing tank 28 are formed at positions that become the washing section 16 and the desensitizing processing section 18. Yes. Further, the processing tank 22 is provided with a space for the insertion section 34 on the upstream side of the developing tank 24 (upstream in the transport direction of the printing plate 12), and a space for the drying section 20 is formed on the downstream side of the finishing processing tank 28. Has been.

  In the outer panel 30 covering the periphery of the processing tank 22, a slit-like insertion port 32 is formed on the insertion side of the printing plate 12 to the printing plate processor (left side in FIG. 1). An insertion portion 34 is formed on the insertion port 32 side of the portion 14.

  The printing plate processor is provided with covers 36 and 38 that cover the upper part of the processing tank 22 and the upper part of the drying unit 20. The cover 36 on the insertion port 32 side covers the upper part of the washing unit 16 from the insertion part 34 of the processing tank 22, and the cover 38 is disposed so as to cover between the upper part of the washing unit 16 and the upper part of the drying unit 20.

  The cover 36 is provided with a reentry insertion port (sub-insertion port) 40 for inserting the printing plate 12 between the developing unit 14 and the water washing unit 16. The sub insertion port 40 is used for inserting the thermal positive printing plate 12 for performing processing in the printing plate processor 10 excluding processing in the developing unit 14.

A rubber conveyance roller pair 42 is disposed in the insertion portion 34 adjacent to the insertion port 40. The printing plate 12 on which the image has been printed is inserted between the conveyance roller pair 42 by being inserted along the direction of arrow A from the insertion port 32.
The conveyance roller pair 42 is rotationally driven, and sends the printing plate 12 to the developing unit 14 at an angle in a range of about 15 ° to 31 ° with respect to the horizontal direction while drawing the printing plate 12 from the insertion port 32. In the printing plate processor used for processing the single-sided type printing plate 12 (12, 12C), the photosensitive layer (photosensitive surface) is inserted from the insertion port 32 in a state of being directed upward. That is, the printing plate 12 is processed by the printing plate processor with the photosensitive surface facing upward.

The developing tank 24 formed in the processing tank 22 has a substantially mountain shape with the bottom center protruding downward, and stores a developing solution for performing the developing processing of the printing plate 12.
In the developing tank 24, a transport roller 48 is disposed on the insertion portion 34 side that is the upstream portion of the transport path of the printing plate 12. In the developing tank 24, a conveyance roller pair 50 is arranged at the center of the conveyance path of the printing plate, and a conveyance roller pair 52 is arranged on the washing unit 16 side which is a downstream part.
Further, the developing tank 24 transports a guide plate, a transport roller, etc. according to the type of the printing plate 12 to be processed between the transport roller 48 and the transport roller pair 50 and between the transport roller pair 50 and the transport roller pair 52. By providing parts, a brush roller used as a rubbing member, a backup roller or a guide plate, a substantially U-shaped transport path for transporting the printing plate 12 while being immersed in the developer in the developing tank 24 is provided. It is formed. The configuration of the transport path in the developing tank 24 will be described later.

On the other hand, in the developing tank 24, the brush roller 142 and the transport roller 60 are disposed between the transport roller pair 50 and 52. The brush roller 142 is used as an example of a rubbing member, and the brush roller 142 and the conveyance roller 60 are attached so as to face the upper surface side of the printing plate 12 conveyed between the conveyance roller pair 50 and 52. Yes. The brush roller 142 contacts the upper surface of the printing plate 12 while rotating in a predetermined direction and a predetermined rotation direction, thereby brushing the photosensitive layer on the upper surface side of the printing plate 12 and removing an unnecessary photosensitive layer with a developer. Has come to promote.
The printing plate 12 drawn from the insertion port 32 by the conveyance roller pair 42 passes below the conveyance roller 48 and is fed between the conveyance roller pair 50, and further along the bottom surface of the developing tank 24 by the conveyance roller 50. Then, it is guided obliquely upward toward the conveying roller pair 52. At this time, the upper surface side of the printing plate 12 is brushed by the brush roller 142.
Further, the conveying roller pair 52 is formed, for example, by a rubber roller at the outer periphery, and is fed into the washing unit 16 while sandwiching the printing plate 12 and pulling it out from the developing tank 24.

  In the developing tank 24, spray pipes 54 and 56 are provided between the conveyance roller 48 and the conveyance roller pair 50 and near the bottom surface between the conveyance roller pair 50 and the conveyance roller pair 52. The developer in the developing tank 24 sucked by a pump (not shown) is supplied to the spray pipes 54 and 56, and the developer is ejected from the spray pipes 54 and 56. Thereby, the developing solution in the developing tank 24 is agitated so that the printing plate 12 can be uniformly processed. At this time, the developer is ejected from the spray pipe 54 along the width direction that is orthogonal to the transport direction of the printing plate 12, so that the developer ejected from the spray pipe 54 is transported in the developer tank 24. It goes around the front and back surfaces of the printing plate 12 to prevent rapid development processing and uneven processing of the printing plate 12.

Further, a fixed amount of replenisher is replenished to the developing unit by a replenishment pump (not shown). The replenishment can be performed by measuring the plate length of the printing plate with a sensor in the insertion portion, calculating the area from the pre-input plate width, and replenishing. Furthermore, you may replenish at a fixed time interval.
Furthermore, an electric conductivity sensor (not shown) may be incorporated in the developing tank and supplemented from the change.

  The printing plate 12 drawn from the developing tank 24 by the transport roller pair 52 is sent to the washing unit 16 while the developer attached to the surface is squeezed out by the transport roller pair 52.

In the washing section 16, a conveyance path for conveying the printing plate 12 in a substantially horizontal state is formed by a pair of conveyance rollers 62 and 64 disposed above the washing tank 26. , 64 and horizontally transported above the washing tank 26.
Between the conveyance roller pairs 62 and 64, spray pipes 66 and 68 are arranged in pairs with the conveyance path of the printing plate 12 interposed therebetween. A metal rod rod 67 for discharging liquid is disposed on the upper roller 62A of the conveying roller pair 62.
Further, according to the present invention, a liquid brush 69 is disposed and is in contact with the lower roller 62B as a liquid discharging member for discharging liquid. Here, the liquid cutting brush 69 and the liquid cutting metal rod 67 do not have a drive source and are in contact with the transport rollers 62B and 62A, respectively, but the configuration is not limited to this, and a separate drive source is provided and rotated. Anyway. Further, the position where the liquid draining member is brought into contact with the lower roller of the washing inlet is not particularly limited, and an effect can be obtained regardless of the place. However, the position is preferably 90 degrees or more in the rotation direction from the nip point, more preferably 120 degrees. It is good to arrange in the above position.
In addition, at an angle of 270 degrees or more, the dripping water washing solution is trapped, and on the contrary, the effect of draining is reduced.

FIG. 2 is a diagram comparing the flush inlet vertical roller (a) according to the present invention with the flush inlet vertical roller (b) of the conventional apparatus. In the conventional apparatus (b), the washing water discharged from the washing part spray pipe 66 hits the upper and lower rollers 62A and 62B at the washing inlet and wraps around the developing part while adhering to the lower roller 62B, and the developing part side meniscus of the inlet roller. A considerable amount of washing water is stored in the M ′ portion. Therefore, when the lithographic printing plate 12 was brought in from the developing section, washing water was taken out on the plate and became liquid dripping.
On the other hand, in the apparatus (a) of the present invention, the washing water discharged from the washing part spray pipe 66 hits the upper and lower rollers 62A and 62B at the washing inlet and tries to go around to the developing part side while adhering to the lower roller 62B. The cleaning water adhering to the lower roller 62B is scraped off by the liquid brush 69, and eventually only a small amount of cleaning water is stored in the developing portion side meniscus M portion of the inlet roller. Therefore, even if the planographic printing plate 12 is brought in from the developing portion, the washing water is not taken out on the plate, and no dripping occurs.

In this embodiment, the pile brush 69 is described as a liquid cutting member as an example. However, the liquid cutting member may be a channel brush, a torsion brush, a planting brush, a carpet brush, a Morton roller, or any other blade, rod bar, etc. But you can use it.
As the channel brush, long so-called channel brushes as disclosed in Japanese Utility Model Laid-Open Nos. 62-167253, 4-63447, 4-64128, and Japanese Patent Laid-Open No. 6-186751 are disclosed. A (band-like brush) that is spirally wound around the surface of the roller body is used.
As the torsion brush, the one in which a torsion brush is inserted into a spiral groove provided on the shaft as disclosed in JP-A-3-87832 and spirally wound around the shaft is used.
As an implantation brush, what is created by the method of making a small hole in a shaft roller and implanting a brush material is used.
As a carpet brush, an elongated belt in which a hair material is woven into a woven fabric is wound around the shaft roller as disclosed in JP 2001-5193 A and JP 2001-66788 A. Is used.
As the Molton roller, a roller part disclosed in JP-A-10-198044 is covered with a cylindrical sliding contact material made of a fiber knitted fabric and the end on the mounting side is tightened. it can.

  As the material, natural fibers such as horse hair and pig hair, artificial fibers, metal fibers, and the like can be used, but artificial fibers are preferable from the viewpoint of chemical resistance. Man-made fibers include polyamides such as nylon 6, nylon 6,6, nylon 6,10, nylon 6,12, nylon 12. Polyesters such as polyethylene terephthalate and polybutylene terephthalate (PBT). Polyacrylics such as polyacrylonitrile and poly (meth) acrylate. Polyolefins such as polyethylene, polypropylene, polystyrene, polyvinyl chloride, polyvinylidene chloride, celluloses such as acetyl cellulose, polyurethanes such as polyurethane, polyphenylene sulfite, ethylene / tetrafluoroethylene copolymer, polyvinylidene fluoride, etc. Fluororesins are used, but considering elasticity, rigidity, wear resistance, heat resistance, chemical resistance (especially alkali resistance), water supply, moisture absorption, etc., nylon 6, nylon 6,6, nylon 6, 10, nylon 6,12, nylon 12, polypropylene, polybutylene terephthalate, and polyethylene terephthalate are preferable, and nylon nylon 6,6, nylon 6,10,6,12, nylon 12, and polypropylene are more preferable.

For example, washing water (hereinafter referred to as “washing water”) is stored in the washing tank 26 as a cleaning agent. In the automatic developing device 10, spraying is performed in synchronization with the conveyance of the printing plate 12 by a water supply pump (not shown). Rinsing water in the rinsing tank 26 is supplied to the pipes 66 and 68. As a result, washing water is ejected from the spray pipes 66 and 68 toward the printing plate 12 to wash away the developer adhering to the surface of the printing plate 12. Here, an example is described in which a washing brush is not provided on the surface of the washing part plate material photosensitive layer, but a washing brush may be provided on the side of the plate material photosensitive layer.
The washing water supplied to the printing plate 12 is squeezed from the front and back surfaces of the printing plate 12 together with the developer and the like adhering to the front and back surfaces of the printing plate 12 when the printing plate 12 is held between the conveying roller pair 64 and sent out. It is dropped and collected in the washing tank 26. In addition, the spraying direction of the washing water from the spray pipes 66 and 68 is the upstream side in the transport direction of the printing plate 12. The spray pipe 68 is on the downstream side in the conveyance direction of the printing plate 12, but is not limited to this and may be in another direction. Further, a new washing water solution is supplied to the washing tank 26 by means (not shown) according to the processing amount of the printing plate 12.
Furthermore, a preservative may be automatically added to suppress the growth of scales and fungi. As a scale inhibitor, BK-3 manufactured by Fuji Photo Film Co., Ltd. is preferably used.

The finishing processing unit 18 is provided with a conveying roller pair 70 above the finishing processing tank 28, and the printing plate 12 is conveyed toward the conveying roller pair 70 by the conveying roller pair 64, whereby the finishing processing unit 18 Is conveyed by the conveying roller pair 70 and sent toward the drying unit 20.
The finishing processing unit 18 is provided with a spray pipe 72 above the transport path of the printing plate 12 and a spray pipe 74 below the transport path. The spray pipes 72 and 74 have a longitudinal direction (axis direction) along the width direction of the printing plate 12 and are arranged above and below the conveyance path of the printing plate 12. A plurality of discharge holes are formed in the spray pipes 72 and 74 along the width direction of the thermal positive printing plate 12.

  The finishing treatment tank 28 stores a gum solution used for protecting the printing plate 12. The gum solution is supplied to the spray pipes 72 and 74 in synchronization with the conveyance of the printing plate 12. The spray pipe 72 drops the gum solution onto the printing plate 12 and spreads it on the surface of the printing plate 12 and applies it. The spray pipe 74 discharges the gum solution from the discharge hole toward the back surface of the printing plate 12 and applies the gum solution to the back surface of the printing plate 12.

  The printing plate 12 has a protective film formed by a gum solution applied to the front and back surfaces. In addition, the discharge direction of the gum solution from the spray pipe 72 is not limited to the downstream side in the transport direction of the printing plate 12, and may be in other directions. A rectifying plate is provided and ejected toward the rectifying plate. The gum solution may be applied to the surface of the printing plate 12 while being uniformly diffused along the width direction of the printing plate 12 with a current plate. Further, instead of the spray pipe 74, a discharge unit or the like for applying the gum solution to the back surface of the printing plate 12 by moving the printing plate 12 while contacting the discharged gum solution may be used.

  The finishing processing unit 18 is provided with a cleaning spray 76 above the conveying roller pair 70, and a cleaning roller 78 that rotates while contacting the rollers above the conveying roller pair 70. At a predetermined timing, the cleaning water is dropped from the cleaning spray 76 to the contact position between the cleaning roller 78 and the roller above the conveying roller pair 70 via the rectifying plate 80, so that the cleaning water is supplied to the conveying roller pair 70. The gum solution is uniformly diffused on the peripheral surfaces of the upper rollers, and the gum solution is washed away from the peripheral surfaces of the upper and lower rollers of the conveying roller pair 70, and the gum solution adheres to the peripheral surfaces of the rollers and damages the thermal positive printing plate 12. I try to prevent it. The printing plate 12 to which the gum solution has been applied by the finishing processing unit 18 is sandwiched between the conveying roller pair 70, and the gum solution remains on the front and back surfaces slightly (the gum solution remains as a thin film) to the drying unit 20. Sent.

  In the printing plate processor 10, a partition plate 82 is provided between the finishing processing unit 18 and the drying unit 20. The partition plate 82 is disposed above the conveying path of the printing plate 12 so as to face the upper end of the processing tank 22, and thereby, a slit-shaped insertion port is provided between the finishing processing unit 18 and the drying unit 20. 84 is formed. The partition plate 82 has a double structure, whereby a groove-like air passage is formed on the drying portion 20 side of the insertion opening 84, and the air in the drying portion 20 enters the air passage. Thus, the air in the drying unit 20 is prevented from entering the desensitizing processing unit 18 from the insertion port 84. In the drying unit 20, a support roller 86 that supports the printing plate 12 is disposed in the vicinity of the insertion port 84, and in the vicinity of the central portion in the conveyance direction of the thermal positive printing plate 12 and the discharge port 88. A conveying roller pair 90 and a conveying roller pair 92 are provided. The thermal positive printing plate 12 is transported in the drying unit 20 by a support roller 86 and a pair of transport rollers 90 and 92.

  Ducts 94 and 96 are disposed between the support roller 86 and the conveyance roller pair 90 and between the conveyance roller pair 90 and the conveyance roller pair 92 in pairs with the conveyance path of the printing plate 12 interposed therebetween. The ducts 94 and 96 are disposed such that the longitudinal direction thereof is along the width direction of the thermal positive printing plate 12, and a slit hole 98 is provided on the surface facing the conveyance path of the printing plate 12.

  The ducts 94 and 96 discharge the dry air from the slit hole 98 toward the conveying path of the printing plate 12 when the dry air generated by the dry air generating means (not shown) is supplied from one end side in the longitudinal direction. And sprayed onto the printing plate 12. Thereby, as for the printing plate 12, the gum liquid currently apply | coated to the front and back is dried, and a protective film is formed.

  On the other hand, the developing unit 14 is provided with a shielding lid 100 such that the lower surface is below the level of the developer stored in the developer tank 24, and the level of the developer in the developer tank 24 is in contact with air. The area is narrowed. Further, the auxiliary insertion port (reentry insertion port) 40 of the cover 36 is blocked by a shielding member (not shown), and this shielding member prevents outside air from entering the developing unit 14.

  The shielding lid 100 is provided with a selection part (to be described later) together with a concave portion 100A into which the brush roller 142 and the conveying roller 60 project from the developer surface, and a roller above the conveying roller pair 52. A recess 100B into which a part enters is formed.

  In the automatic developing apparatus 10, by disposing the liquid level lid 100 in the developing tank 24, deterioration due to the developer in the developing tank 24 coming into contact with carbon dioxide in the air or the like is prevented. I am doing so. A blade-shaped shielding member (not shown) formed of silicon rubber or the like is provided between the shielding lid 100 and the processing tank 22 and the conveying roller 48 or the conveying roller pair 52, so that the developer in the developing tank 24 is fresh. It may be possible to prevent contact with outside air or evaporation of water in the developer, which is more preferable.

  In the developing tank 24 of the automatic developing device 10, a conveyance roller 48 </ b> A is disposed below the conveyance roller 48 so as to face the conveyance roller 48. As a result, the printing plate 12 is inserted between the transport rollers 48 and 48 </ b> A by the transport roller pair 42 of the insertion portion 34. The conveyance roller 48 </ b> A rotates following the rotation of the conveyance roller 48, sandwiches the printing plate 12 inserted between the conveyance roller 48 and draws it into the developing tank 24.

In the developing tank 24, a guide plate 44 is disposed between the conveyance roller 48 and the conveyance roller pair 50. The guide plate 44 guides the printing plate 12 drawn by the transport rollers 48 and 48A so as to be inserted between the transport roller pair 50 at a predetermined angle.
A guide plate 46 is disposed on the conveyance roller pair 50 and the conveyance roller pair 52. The guide plate 48 guides the thermal positive printing plate 12 fed out by the transport roller pair 50 toward the transport roller pair 52 along the bottom surface of the developing tank 24.

  The guide plate 46 is opposed to the brush roller 142 and the transport roller 60. The brush roller 142 sandwiches the printing plate 12 conveyed on the upper surface of the guide plate 46 with the guide plate 46 with a predetermined brush pressure. In this state, the brush roller 142 is rotationally driven in a predetermined direction, whereby the surface of the printing plate 12 is brushed and immersed in the developer to facilitate the removal of the photosensitive layer. The transport roller 60 prevents the printing plate 12 being transported on the guide plate 46 while being brushed by the brush roller 142 from being lifted from the guide plate 46, so that the printing plate 12 is moved on the guide plate 46. The guide is surely guided toward the transport roller pair 52.

Next, materials used for the development system will be described.
The photosensitive lithographic printing plate to which the alkali developing solution of the present invention can be applied is not particularly limited, and various lithographic printing plates in which an image recording layer such as a photosensitive layer and a heat-sensitive layer is provided on a support. List the original version. Examples of the image recording layer include thermal positive types described in JP-A-7-285275 and Japanese Patent Application No. 2002-154279, JP-A-7-20625, and JP-A-11-218903. And the thermal poly negative type described in JP-A Nos. 2001-100412 and 2002-169282.

  Particularly preferred are the multilayer thermal positive types described in JP-A-11-218914, Japanese Patent Application No. 2002-499707, Japanese Patent Application No. 2003-189095, and Japanese Patent Application No. 2003-181121. The thermal positive type of the multilayer may have a multilayer structure of at least two layers.

  The developer used in the present invention contains the following components. Developer (Alkaline Agent) The developer and developer replenisher used in the developing method of the present invention are alkaline aqueous solutions having a pH of 10.0 to 13.5, more preferably 11.0 to 13.3. Conventionally known alkaline aqueous solutions can be used as the developer and developer replenisher. For example, sodium silicate, potassium, tribasic sodium phosphate, potassium, ammonium, dibasic sodium phosphate, potassium, ammonium, sodium bicarbonate, potassium, ammonium, sodium carbonate, potassium, Examples include inorganic alkaline agents such as ammonium, sodium hydrogen carbonate, potassium, ammonium, sodium borate, potassium, ammonium, sodium hydroxide, ammonium, potassium, and lithium. Moreover, monomethylamine, dimethylamine, trimethylamine, monoethylamine, diethylamine, triethylamine, monoisopropylamine, diisopropylamine, triisopropylamine, n-butylamine, monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, diisopropanolamine, Organic alkali agents such as ethyleneimine, ethylenediamine, and pyridine are also used.

Among these alkali agents, aqueous silicate solutions such as sodium silicate and potassium silicate are preferred. The reason for this is that the ratio of pH and developability depends on the ratio (generally expressed as a molar ratio of [SiO ₂ ] / [M ₂ O]) and concentration of silicon oxide SiO ₂ and alkali metal oxide M ₂ O, which are silicate components. This is because adjustment is possible. For example, the molar ratio of SiO ₂ / Na ₂ O is 1.5 to 2.5 (that is, [SiO ₂ ] / [Na ₂ O] is 1.5 to 2.5), and the content of SiO ₂ is An alkali metal silicate composed of an aqueous solution of 1 to 4% by weight of sodium silicate is preferably used in the present invention.
A more preferable alkaline agent is a buffer solution composed of a weak acid and a strong base. The weak acid used as such a buffer is preferably one having an acid dissociation constant (pKa) of 10.0 to 13.3,
Particularly preferred are those having a pKa of 11.0 to 13.1. For example, in the case of sulfosalicylic acid, the third dissociation constant is 11.7, which can be suitably used in the present invention. That is, in the case of a polybasic acid, it can be used in the present invention if at least one acid dissociation constant is within the above range.

  Such a weak acid is selected from those described in IONISATION CONSTANTS OF ORGANIC ACIDS INAQUEOUS SOLUTION issued by Pergamon Press, for example, 2,2,3,3-tetrafluoropropanol-1 (pKa12.74), Alcohols such as trifluoroethanol (12.37) and trichloroethanol (12.24), and aldehydes such as pyridine-2-aldehyde (12.68) and pyridine-4-aldehyde (12.05) Sorbitol (13.0), sucrose (12.7), 2-deoxyribose (12.61), 2-deoxyglucose (12.51), glucose (12.46), galactose (same) 12.35), Ara Vinose (12.34), xylose (12.29), fructose (12.27), lipos (12.22), mannose (12.08), L-ascorbic acid (11.34) Sugars, salicylic acid (13.0), 3-hydroxy-2-naphthoic acid (12.84), catechol (12.6), gallic acid (12.4), sulfosalicylic acid (11. 7), 3,4-dihydroxysulfonic acid (12.2), 3,4-dihydroxybenzoic acid (11.94), 1,2,4-trihydroxybenzene (11.82), hydroquinone (same as above) 11.56), compounds having a phenolic hydroxyl group such as pyrogallol (11.34) and resorcinol (11.27), 2-butanone oxime (12.45), acetoxy (12.42), 1,2-cycloheptanedione dioxime (12.3), 2-hydroxybenzaldehyde oxime (12.10), dimethylglyoxime (11.9), ethanediamide dioxime (Id. 11.37), oximes such as acetophenone oxime (No. 11.35), 2-quinolone (No. 11.76), 2-pyridone (No. 11.65), 4-quinolone (No. 11.28), Amino acids such as 4-pyridone (11.12), 5-aminovaleric acid (10.77), 2-mercaptoquinoline (10.25), 3-aminopropionic acid (10.24), fluorouracil (13.0), guanosine (12.6), uridine (12.6), adenosine (12.56), inosine (12.5), guanine (12) 3) Nucleic acid-related substances such as Citidin (same as 12.2), Cytosine (same as 12.2), Topoxanthin (same as 12.1), Xanthine (same as 11.9), In addition, Diethylaminomethylphosphonic acid (same as 12) .32), 1-amino-3,3,3-trifluorobenzoic acid (12.29), isopropylidene diphosphonic acid (12.10), 1,1-ethylidene diphosphonic acid (11.54). ), 1-hydroxy 1,1-ethylidene diphosphonate (11.52), benzimidazole (12.86), thiobenzamide (12.8), picoline thioamide (12.55), barbituric acid ( And weak acids such as 12.5). Sodium hydroxide, ammonium, potassium and lithium are used as strong bases to be combined with these weak acids.

  These alkali agents are used alone or in combination of two or more. Of these alkaline buffers, sulfosalicylic acid, salicylic acid, saccharose and sorbitol are combined with sodium hydroxide and potassium hydroxide. Among them, a preferred combination is sorbitol and potassium hydroxide or sodium hydroxide. The above various alkali agents are used by adjusting the pH within a preferable range depending on the concentration and combination.

(Surfactant)
To the developer and replenisher used in the present invention, various surfactants and organic solvents can be added as necessary for the purpose of promoting developability, dispersing development residue, and improving ink affinity of the printing plate image area. Preferred surfactants include anionic, cationic, nonionic and amphoteric surfactants.

(Development stabilizer)
Various development stabilizers are used in the developer and replenisher used in the present invention. Preferred examples thereof include polyethylene glycol adducts of sugar alcohols described in JP-A-6-282079, tetraalkylammonium salts such as tetrabutylammonium hydroxide, phosphonium salts such as tetrabutylphosphonium bromide, and iodonium such as diphenyliodonium chloride. A salt is a preferred example.

(Organic solvent)
If necessary, an organic solvent is added to the developer and the development replenisher. As such an organic solvent, those having a solubility in water of about 10% by weight or less are suitable, and preferably those having a solubility in water of 5% by weight or less are selected. For example, 1-phenylethanol, 2-phenylethanol, 3-phenyl-1-propanol, 4-phenyl-1-butanol, 4-phenyl-2-butanol, 2-phenyl-1-butanol, 2-phenoxyethanol, 2- Benzyloxyethanol, o-methoxybenzyl alcohol, m-methoxybenzyl alcohol, p-methoxybenzyl alcohol, benzyl alcohol, cyclohexanol, 2-methylcyclohexanol, 3-methylcyclohexanol and 4-methylcyclohexanol, N-phenylethanol Examples thereof include amines and N-phenyldiethanolamine. The content of the organic solvent is 0.1 to 5% by weight with respect to the total weight of the used solution. The amount used is closely related to the amount of surfactant used, and it is preferable to increase the amount of surfactant as the amount of organic solvent increases. This is because the amount of the surfactant is small, and if the amount of the organic solvent is large, the organic solvent is not completely dissolved, and therefore it is impossible to expect good developability.

(Reducing agent)
A reducing agent is further added to the developer and replenisher used in the present invention. This prevents stains on the printing plate, and is particularly effective when developing a negative photosensitive lithographic printing plate containing a photosensitive diazonium salt compound. Preferable organic reducing agents include phenol compounds such as thiosalicylic acid, hydroquinone, metol, methoxyquinone, resorcin, and 2-methylresorcin, and amine compounds such as phenylenediamine and phenylhydrazine. More preferable inorganic reducing agents include sodium, potassium and ammonium salts of inorganic acids such as sulfurous acid, bisulfite, phosphorous acid, hydrogen phosphite, dihydrogen phosphite, thiosulfuric acid and dithionite. A salt etc. can be mentioned. Among these reducing agents, sulfites are particularly excellent in the antifouling effect. These reducing agents are preferably contained in the range of 0.05 to 5% by weight with respect to the developer at the time of use.

(Organic carboxylic acid)
An organic carboxylic acid can also be added to the developer and replenisher used in the present invention. Preferred organic carboxylic acids are fatty acid carboxylic acids and aromatic carboxylic acids having 6 to 20 carbon atoms. The amount added is from 0.1 to 10% by weight, more preferably from 0.5 to 4% by weight, based on the developing solution in use.

(Other)
The developer and replenisher used in the present invention may further contain an antifoaming agent, a hard water softening agent, and the like, if necessary. Examples of water softeners include polyphosphoric acid and its sodium, potassium and ammonium salts, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, triethylenetetraminehexaneacetic acid, hydroxyethylethylenediaminetriacetic acid, nitrilotriacetic acid, 1,2-diaminocyclohexanetetra Aminopolycarboxylic acids such as acetic acid and 1,3-diamino-2-propanoltetraacetic acid and their sodium, potassium and ammonium salts, aminotri (methylenephosphonic acid), ethylenediaminetetra (methylenephosphonic acid), diethylenetriaminepenta (methylene Phosphonic acid), triethylenetetramine hexa (methylenephosphonic acid), hydroxyethylethylenediaminetri (methylenephosphonic acid) Beauty diphosphonic acid and their sodium salts, potassium salts and ammonium salts. The optimum value of such a hard water softening agent varies depending on its chelating power, the hardness of the hard water used and the amount of hard water. % By weight, more preferably in the range of 0.01 to 0.5% by weight. If the addition amount is less than this range, the intended purpose is not sufficiently achieved. If the addition amount is more than this range, adverse effects on the image area such as color loss will occur.
The remaining component of the developer and the replenisher is water, but various additives known in the art can be added as required. It is advantageous in terms of transportation that the developer and replenisher used in the present invention are concentrated solutions in which the water content is less than in use, and diluted with water during use. In this case, the degree of concentration is appropriate such that each component does not cause separation or precipitation. By using the developer as described above in the present invention, the occurrence of image defects and the like can be more significantly suppressed.

The operation of the embodiment of the present invention will be described in detail below.
The printing plate processor 10 shown in FIG. 1 generally applies a gum solution to a developing section for processing a photosensitive lithographic printing plate with a developer, a water washing section for washing treatment, and a lithographic printing plate after washing with water. There are provided a finisher portion for performing a crystallization treatment and a drying portion for drying the lithographic printing plate coming out of the finisher portion.

  As described above, the planographic printing plate conveyed to the washing unit by the developing tank outlet roller is sandwiched and conveyed by the washing inlet roller pair. On the planographic printing plate discharged from the developing section, even after the developing solution is squeezed by the developing outlet roller, the developing solution remains in a thin film state, and the development proceeds slightly until it is inserted into the washing section. The washing water has already been discharged from the washing section spray pipe, and the washing water has been applied to the washing section entrance roller before the lithographic printing plate passes. A metal rod bar is provided on the upper roller of the washing inlet, and the washing water discharged from the spray pipe is drained to prevent the washing water from flowing around. A liquid draining member is also provided in the lower roller of the washing inlet, and the washing water discharged from the spray pipe is drained like the upper roller to suppress the circulation of the washing water.

In the case where the liquid draining member described above is not provided, the washing water on the washing section inlet roller is carried and accumulated on the rotating roller to the meniscus section on the developing tank side. When the lithographic printing plate discharged from the developing tank enters the rinsing unit entrance roller, the washing water accumulated in the meniscus portion flows out onto the lithographic printing plate and flows on the lithographic printing plate as liquid dripping. At the location where dripping occurs, the slight progress of development by the remaining developer is stopped by the washing water, and the progress of development becomes slower than at the location where no dripping has occurred. In the halftone image, the image line tends to be thinned as the development progresses, and in the liquid dripping portion where the development progress is slowed, the method of thinning the image line becomes small, so that the halftone dot area ratio tends to be slightly increased. This is a cause of occurrence of image unevenness, and this image unevenness can be visually recognized even in printing. In high-definition images, the peripheral length of the image area becomes long, and the influence of the slight development progress by the remaining developer on the halftone dot area rate is large. large. As described above, specific examples of high-definition images that have a great effect include an AM screen having 250 lines or more, the FM screen described above, and a hybrid screen. In the FM screen and the hybrid screen, when the size of the minimum pixel constituting the halftone dot is 30 μm or less, image unevenness is particularly likely to occur, and the present invention is effective.
Here, the size of the minimum image represents the length of one side of the minimum pixel constituting the image. FIG. 5 shows an example of the length of one side of the minimum pixel constituting the image.
In the figure, the minimum image can be seen on the highlight side of the FM screen as shown in (a), and can also be seen partially in the halftone of the FM screen and on the shadow side as shown in (b).

  Further, in the thermal positive plate, the image line is likely to be thin, and the difference in the dot area ratio between the dripping portion and the non-generating portion tends to increase. There are two types of thermal positive plates, one having a single layer structure and the other having a laminated structure. In particular, in a plate having a photosensitive layer formed in a laminate, the image unevenness is likely to occur. In the laminated thermal positive plate, the elution prevention function of the unexposed area is imposed on the upper layer, and the lower layer is designed to be easily dissolved in the developer. Even after being discharged from, the degree of image line thinning due to the remaining developer is large. For this reason, a density difference from a portion where development is stopped due to dripping is likely to occur. In such a system, the effect of draining the washing inlet roller is particularly great.

FIG. 3 shows an example of the second embodiment of the present invention. In FIG. 3, a liquid draining rod 69a is used instead of the liquid draining brush 69 that scrapes off the liquid on the lower roller of the flush inlet roller 62B. As described above, the draining rod 69a is also provided in the washing inlet lower roller 62B, and the washing water discharged from the spray pipe is drained in the same manner as the upper roller to suppress the circulation of the washing water. In the case where the cutting rod 69a is not provided, the washing water on the washing roller inlet roller is transported and accumulated on the rotating roller to the meniscus portion on the developing tank side, and is discharged from the developing tank. However, when the water enters the washing unit inlet roller, the washing water accumulated in the meniscus portion flows out onto the lithographic printing plate and flows on the lithographic printing plate as dripping. At the location where dripping occurs, the slight progress of development by the remaining developer is stopped by the washing water, and the progress of development becomes slower than at the location where no dripping has occurred. In the halftone image, the image line tends to be thinned as the development progresses, and in the liquid dripping portion where the development progress is slowed, the method of thinning the image line becomes small, so that the halftone dot area ratio tends to be slightly increased. This is a cause of occurrence of image unevenness, and this image unevenness can be visually recognized even in printing. In high-definition images, the peripheral length of the image area becomes long, and the influence of the slight development progress by the remaining developer on the halftone dot area rate is large. It was big.
As described above, specific examples of high-definition images that have a great effect include an AM screen having 250 lines or more, the FM screen described above, and a hybrid screen. In the FM screen and the hybrid screen, when the size of the minimum pixel constituting the halftone dot is 30 μm or less, image unevenness is particularly likely to occur, and the present invention is effective.

An example of the third embodiment of the present invention is shown in FIG.
In the third embodiment, the liquid draining member is a liquid draining blade 69b that scrapes off the liquid on the lower roller. As described above, the draining rod 69a is also provided in the washing inlet lower roller 62B, and the washing water discharged from the spray pipe is drained in the same manner as the upper roller to suppress the circulation of the washing water. In the case where the cutting rod 69a is not provided, the washing water on the washing roller inlet roller is transported and accumulated on the rotating roller to the meniscus portion on the developing tank side, and is discharged from the developing tank. However, when the water enters the washing unit inlet roller, the washing water accumulated in the meniscus portion flows out onto the lithographic printing plate and flows on the lithographic printing plate as dripping. At the location where dripping occurs, the slight progress of development by the remaining developer is stopped by the washing water, and the progress of development becomes slower than at the location where no dripping has occurred. In the halftone image, the image line tends to be thinned as the development progresses, and in the liquid dripping portion where the development progress is slowed, the method of thinning the image line becomes small, so that the halftone dot area ratio tends to be slightly increased. This is a cause of occurrence of image unevenness, and this image unevenness can be visually recognized even in printing. In high-definition images, the peripheral length of the image area becomes long, and the influence of the slight development progress by the remaining developer on the halftone dot area rate is large. It was big.
As described above, specific examples of high-definition images that have a great effect include an AM screen having 250 lines or more, the FM screen described above, and a hybrid screen. In the FM screen and the hybrid screen, when the size of the minimum pixel constituting the halftone dot is 30 μm or less, image unevenness is particularly likely to occur, and the present invention is effective.

Hereinafter, although the remarkable effect of the present invention is explained based on an example, the range of the present invention is not limited to these examples.
(1) Use of original HP-S for lithographic printing plates:
A lithographic printing plate precursor HP-S (Fuji Photo Film Co., Ltd., thermal positive multi-layer printing plate) is produced with a Trend setter VX manufactured by Creo Co., Ltd. with an FM screen Staccato 20 at a drum intensity of 150 W and a drum rotation speed of 150 rpm and an AM screen 175 lpi as a comparison. After drawing a 50% flat mesh, the initial charging developer DT-2 (developer for thermal positive manufactured by Fuji Photo Film Co., Ltd.) was watered 1: 8 on the self-described machine described in detail in FIG. Dilute with and put in. Development processing was carried out with the developer temperature kept at 30 ° C. and a development time of 12 seconds. Water was added to the washing section. The finishing section was loaded with finisher FG-1 (diluted 1: 1) manufactured by Fuji Photo Film Co., Ltd. and subjected to finishing treatment.

Table 1 shows the relationship between the water drainage member at the bottom of the washing unit inlet and the image unevenness (drip).
The types of liquid draining member are nylon brush (nylon 6 · 10), polypropylene brush, molton roller, rubber blade, metal rod (Examples 1 to 5), and none (comparative example).
As an exposure method,
(A) Co-Re screen 250 lpi
(B) FM Staccato20
(C) Randot20
(D) Hybrid screen Fairdot
(E) AM screen 175 lpi
Carried out.

Table 1 shows that (1) Nylon brush (nylon 6 · 10), polypropylene brush, Molton roller, rubber blade, and metal rod can be used in any exposure method (a) to (d). No one was seen (○).
(2) However, if none of these was used, dripping occurred in the exposure methods (a) to (d).
(3) No dripping was observed on the conventional AM screen 175 lpi without using any of these (◯). This means that with the conventional AM screen 175 lpi or the like that does not have high-definition exposure, there is no need to worry about image unevenness due to dripping. This dripping is a unique phenomenon that occurs for the first time in high-definition exposure, and it can be seen that dripping is a problem that must be solved for the first time in high-definition exposure.

(2) Use of lithographic printing plate precursor LH-PD:
An original LH-PD for a lithographic printing plate (thermal positive multi-layer printing material manufactured by Fuji Photo Film Co., Ltd.) was used with a LUXEL T9000HS manufactured by Fuji Film, the beam intensity at 70% of full power, an FM screen Randot X20 at a drum rotation speed of 900 rpm, and After drawing a 50% flat screen at 175 lpi on a hybrid screen Fairdot and an AM screen as a comparison, an initial charging developer DT-2 (thermal product manufactured by Fuji Photo Film Co., Ltd.) was used with the self-described machine described in detail in FIG. The positive developer was diluted 1: 8 with water and added. Development processing was carried out with the developer temperature kept at 30 ° C. and a development time of 12 seconds. Water was added to the washing section. Finisher FG-1 (diluted 1: 1) manufactured by Fuji Photo Film Co., Ltd. was introduced into the finishing section.

Similarly, Table 2 shows the relationship between the roller cleaning member at the entrance of the washing unit and image unevenness (drip). The types of liquid draining members are nylon brush (nylon 6 · 10), channel brush, molton roller, plastic blade, plastic rod (Examples 1 to 5), and none (comparative example).
As an exposure method,
(A) Co-Re screen 300 lpi
(B) FM Staccato10
(C) Randot20
(D) Hybrid screen Fairdot
(E) AM screen 175 lpi
Carried out.

It can be seen from Table 2 that (1) When any of nylon brushes (nylon 6 and 10), channel brushes, molton rollers, blades, and metal rods is used, any of the exposure methods (a) to (d) drips. Was not seen (○).
(2) However, if none of these was used, dripping occurred in the exposure methods (a) to (d).
(3) No dripping was observed on the conventional AM screen 175 lpi without using any of these (◯). This means that with the conventional AM screen 175 lpi or the like that does not have high-definition exposure, there is no need to worry about image unevenness due to dripping. This dripping is a unique phenomenon that occurs for the first time in high-definition exposure, and it can be seen that dripping is a problem that must be solved for the first time in high-definition exposure.

  As described above, according to the present invention, the lower roller of the washing unit inlet roller pair of the printing plate processor is drained to prevent dripping from the washing unit inlet roller onto the plate. It is possible to prevent image unevenness that is a problem during image plate making. With this liquid cutting, the printing plate processor can perform processing without causing image unevenness of the planographic printing plate.

1 is an overall configuration diagram of a printing plate processor including a developing unit according to a first embodiment of the present invention. It is the figure which contrasted the flush inlet upper / lower roller (a) which concerns on this invention, and the flush inlet upper / lower roller (b) of a conventional apparatus. It is a whole block diagram of the printing plate processor containing the image development part which concerns on the 2nd Embodiment of this invention. It is a whole block diagram of the printing plate processor containing the image development part which concerns on the 3rd Embodiment of this invention. It is a figure which shows an example of the length of one side of the minimum pixel which comprises an image.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Printing plate processor 12 Printing plate 14 Developing part 16 Washing part 18 Finishing (desensitizing) processing part 20 Drying part 22 Processing tank 24 Developing tank 26 Washing tank 28 Finishing processing tank 30 Outer panel 32 Inserting port 34 Inserting part 36 Insertion Mouth side cover 38 Drying section side cover 40 Reentry insertion slot (sub insertion slot)
42, 48, 50, 52 Conveying roller pair 60 Conveying roller 62, 64 Conveying roller pair 66, 68 Spray pipe 67 Metal rod rod 69 Liquid cutting member (liquid cutting brush)
69a Liquid cutting rod 69b Liquid cutting blade 142 Brush roller 440 Conveying guide plate 441 according to the present invention Nipping member (roller pair) according to the present invention
M Meniscus

Claims (6)

  In a processing apparatus having a lithographic printing plate coated with a photosensitive material for image formation on an FM screen or a high-definition AM screen at least in the order of a development process and a washing process, a pair of sandwiching and conveying the printing plate at the washing process inlet A lithographic printing plate processing apparatus comprising an inlet roller, and a liquid scraping member for scraping off the liquid on a lower roller of the pair of inlet rollers.   2. The lithographic printing plate processing apparatus according to claim 1, wherein the liquid cutting member is a liquid cutting brush that scrapes off the liquid on the lower roller.   2. The lithographic printing plate processing apparatus according to claim 1, wherein the liquid cutting member is a liquid cutting rod that scrapes off the liquid on the lower roller.   2. The lithographic printing plate processing apparatus according to claim 1, wherein the liquid cutting member is a liquid cutting blade that scrapes off the liquid on the lower roller.   The lithographic printing plate processing apparatus according to any one of claims 1 to 4, wherein the lithographic printing plate contains a photothermal conversion agent and is exposed in a heat mode by a laser.   A lithographic printing plate having a photosensitive layer or a heat-sensitive layer is laser-exposed with a high-definition AM screen having 250 lines or more or a high-definition FM screen having a minimum pixel size constituting a halftone dot of 50 μm or less. A lithographic printing plate treatment method comprising transporting and developing while immersed in a developer, washing with water, and finishing, wherein the lithographic printing plate discharged from an exit roller after the development is completed 2. A lithographic printing plate processing method, comprising: scraping off the liquid of the lower roller of the pair of inlet rollers before the pair of inlet rollers in the pair is nipped and conveyed.

Images