JP2007271795A - Plate making method and apparatus for photopolymerizable lithographic printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow plate making by satisfactorily reproducing dots by exposure and development, and to perform exposure with a device which has a simple configuration, is easily controlled and can be manufactured at a low price. <P>SOLUTION: A photopolymerizable lithographic printing plate having an image recording layer using a photo-radical polymerization reaction is irradiated with a light beam modulated based on image data at an output of an image forming level to form a latent image, and a portion in which an image is not formed in the image recording layer is irradiated with a light beam at a low output of a preliminary level to form a latent image having no role in image formation. In a development section, a developer is applied to the image recording layer and the layer is brushed to remove the latent image formed by the light beam of the preliminary level while leaving the latent image formed by the light beam of the image forming level, whereby the latent image is elicited to achieve plate making. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  According to the present invention, a photopolymerizable lithographic printing plate provided with an image recording layer for recording a latent image on a surface of a flat support using radical photopolymerization is preferably subjected to exposure treatment and development treatment. The present invention relates to a photopolymerizable lithographic printing plate making method and plate making apparatus for making a plate by reproducing halftone dots.

  In recent years, in the field of lithographic printing, an unexposed lithographic printing plate is supplied, and image data is computer-processed on the lithographic printing plate to directly modulate the laser beam of the light source to form a lithographic printing plate precursor. An image recording layer in which a latent image is formed in a state in which a lithographic printing plate is immersed in a developer by performing a laser exposure process in which a modulated laser beam is projected to directly record an image on the original image recording layer of the lithographic printing plate A CTP (Computer to Plate) system that directly develops a lithographic printing plate by developing the latent image into a visible image by brushing and removing non-polymerized non-image portions in the plate has been put into practical use.

  In addition, for use in such a CTP system, development of a laser-compatible lithographic printing plate using radical chain polymerization that enables direct exposure of laser light to enable high-sensitivity and fine exposure is in progress. .

  In a lithographic printing plate using such a photo-radical polymerization reaction, when the photopolymerizable material layer is exposed with laser recording light, the radical generated from the radical initiator reacts with the monomer, and the monomer is radicalized. Further, it is an image forming means that a polymer having a large molecular structure is obtained by repeating the reaction with a monomer.

  The photo-radical polymerization reaction performed in such a lithographic printing plate prevents the radical polymerization reaction by the action of deactivating radicals in the image recording layer generated by exposure by oxygen in the photo-polymerizable material layer. This is a factor that decreases the sensitivity of the sex lithographic printing plate.

  For this reason, for example, when a small dot (20 μm × 20 μm) serving as a minimum unit dot for forming an FM screen is exposed on a photopolymerizable lithographic printing plate (photopolymer plate), the time passes after exposure in the image recording layer. Oxygen in the atmosphere that permeates into the surface and dissolved oxygen in the image recording layer eliminates radicals generated by exposure from the top and side of the latent image of the exposed small dots, so photopolymerizable lithographic printing plate The small dot latent image formed on the image recording layer is reduced and thinned. In particular, since there are many unexposed portions around the small dots, there is a lot of dissolved oxygen, and the reproducibility of the small dots is likely to deteriorate significantly.

  Therefore, an exposure means for making a conventional photopolymerizable lithographic printing plate comprises a first laser for recording an image and a second laser for pre-exposure processing, and an image in the image recording layer. It is proposed that the area to be recorded is pre-sensitized with the laser beam irradiated from the second laser, and recording is performed with the laser beam irradiated from the first laser in the high-sensitivity area of the image recording layer. (For example, refer to Patent Document 1).

  However, in the exposure means for making the photopolymerizable lithographic printing plate, the first laser and the second laser must be provided, so the number of parts increases, and the first laser and the second laser Since different exposure operations are performed, there is a problem that the control becomes complicated and the exposure means becomes expensive.

  In addition, in the conventional means for making a photopolymerizable lithographic printing plate, a heat treatment is performed after a certain time has elapsed after exposure processing for forming a latent image by light irradiation on the image recording layer of the photopolymerizable lithographic printing plate. It has been proposed to improve halftone dot reproducibility (see, for example, Patent Document 2).

However, in the conventional means for making a photopolymerizable lithographic printing plate, the reproducibility of small dots is improved, but there is a possibility that the halftone dots may be crushed in a high dot density (halftone dot) region.
EP0639799 JP-A-2005-78012

  In view of the above-described problems, the present invention enables exposure processing and development processing to reproduce a halftone dot and make plate making, and can perform exposure processing with an apparatus that can be easily manufactured at a low cost with a simple configuration. An object of the present invention is to newly provide a plate making method and a plate making apparatus for a photopolymerizable lithographic printing plate.

  The method for making a photopolymerizable lithographic printing plate according to claim 1 of the present invention is a photopolymerizable lithographic printing plate in which an image recording layer is provided on the surface of a support as an image forming means utilizing a photoradical polymerization reaction. An exposure processing step for irradiating a plate with a light beam modulated based on image data at an image forming level output to cause an image radical polymerization reaction to polymerize to form a latent image; and exposure A photopolymerizable lithographic printing plate having a wet brush development type development processing step that reveals a latent image by applying a developing solution or brushing the image recording layer of the processed photopolymerizable lithographic printing plate in the developing solution. In the plate making method, a light beam is applied to the non-image forming portion with a preliminary level output that forms a latent image that can be scraped off by a subsequent development processing step on the non-image forming portion in the image recording layer in the exposure processing step. And irradiating.

  According to the plate making method of the photopolymerizable lithographic printing plate described above, the preliminary level light beam irradiated to the non-image forming part causes the radical initiator to react with each other to generate radicals in the image recording layer. The remaining oxygen quenches radicals so that oxygen does not remain in the image recording layer, and the image recording layer that suppresses inhibition of radical polymerization reaction by oxygen is brought into a highly sensitive state. Since the latent image of the image forming part is formed by exposure with an image forming level light beam with the layer being highly sensitive, the latent image of the small dots formed in the image recording layer is the residual oxygen in the image recording layer. Can be prevented from shrinking and becoming thin, and the reproducibility of halftone dots can be made well. Since the latent image that can be formed in the non-image forming portion is removed by a subsequent development process, an appropriate image can be formed on the photopolymerizable lithographic printing plate that has been made. In addition, in the exposure processing step, an exposure apparatus that performs exposure processing with an image forming level light beam for the image forming unit and processing for exposure with a preliminary level light beam for the non-image forming unit can be easily controlled with a simple configuration. Can be manufactured at low cost.

  The photopolymerizable lithographic printing plate making apparatus according to claim 2 of the present invention comprises a photopolymerizable lithographic plate provided with an image recording layer as a means for image formation utilizing a photoradical polymerization reaction on the surface of a support. An apparatus for making a printing plate, which irradiates an image forming portion of an image recording layer of a photopolymerizable lithographic printing plate with an output light beam at an image forming level to cause a photo radical polymerization reaction to polymerize the image. An exposure apparatus that forms a latent image that is not involved in image formation by forming a latent image for forming and irradiating a non-image forming portion in the image recording layer with a low-level light beam at a preliminary level; A latent image formed by a preliminary level light beam is left by leaving a latent image formed by a light beam at an image forming level by brushing the image recording layer of a photopolymerizable lithographic printing plate subjected to exposure treatment with a developer. To reveal the latent image And having a developing unit for reduction.

  According to a third aspect of the present invention, in the plate making apparatus for the photopolymerizable lithographic printing plate according to the second aspect, the output of the preliminary level of the light beam irradiated to the non-image forming portion is obtained by the following formula and set. It is characterized by doing.

Formula Le <V1 or Le <V1 × α
here,
V1: Experiments for setting an output level at which a latent image is formed to a degree that can be scraped off from the development process of the wet brush development method with respect to an exposure level α: V1 that causes a radical photopolymerization reaction to form a latent image. The coefficient obtained by
Le = preliminary level By configuring as described above, the exposure apparatus unit irradiates the non-image forming unit of the photopolymerizable lithographic printing plate with a preliminary level light beam to cause the radical initiator to react. An image recording layer that generates radicals and oxygen remaining in the image recording layer quenches the radicals so that no oxygen remains in the image recording layer, thereby suppressing inhibition of the radical polymerization reaction by oxygen. In this state, the image recording layer is exposed to a light beam at an image forming level by the exposure device unit to form a latent image in the image forming unit. Thus, it is possible to prevent the latent image of small dots formed on the image recording layer from being reduced and thinned by the influence of residual oxygen in the image recording layer, and to perform plate making with good reproducibility of halftone dots. Since the latent image that can be formed in the non-image forming portion is removed by a subsequent development process, an appropriate image can be formed on the photopolymerizable lithographic printing plate that has been made. In addition, an exposure device that performs exposure processing with an image forming level light beam for an image forming unit and processing for exposure with a preliminary level light beam for a non-image forming unit is manufactured with a simple configuration and is easy to control and inexpensive. Possible.

  According to the plate making method and plate making apparatus of the photopolymerizable lithographic printing plate of the present invention, exposure processing is performed with an apparatus that can be easily manufactured at a low cost with a simple configuration, and further, development processing is performed to satisfactorily generate halftone dots. There is an effect that the plate can be reproduced and reproduced.

Embodiments relating to a plate making method and a plate making apparatus of a photopolymerizable lithographic printing plate of the present invention will be described.
(Method for making photopolymerizable lithographic printing plate)
First, the plate making method of the photopolymerizable lithographic printing plate according to the present embodiment will be described.

  The plate making method of this photopolymerizable lithographic printing plate can be applied to a lithographic printing plate of a photon mode recording system or a heat mode recording system as a means for forming an image using a generally used photo radical polymerization reaction. .

  A lithographic printing plate (radical polymerization type lithographic printing plate) using this photo-radical polymerization reaction is formed, for example, by forming an anodized film on the surface of an aluminum support, and further forming an image recording layer (photosensitive layer) on the anodized film. And a multilayer structure in which the surface of the image recording layer is covered with a protective layer for blocking oxygen.

  In this image recording layer, by irradiating a photopolymerizable material with a laser beam (light beam), radicals generated from the radical initiator react with the monomer, the monomer is radicalized, and further the reaction with the monomer is repeated. As a result, the image forming means solidifies into a polymer having a large molecular structure.

  Further, the protective layer is configured as a layer having an oxygen blocking property in order to prevent oxygen in the atmosphere from being dissolved into the image recording layer.

  The radical polymerization type lithographic printing plate having such a configuration is in a state in which oxygen is dissolved in a saturated state in the image recording layer and the protective layer while a long time elapses from the production to use. Is normal.

  In the plate making method of a photopolymerizable lithographic printing plate according to this embodiment, a latent image is formed by scanning a laser beam (light beam) on a radical polymerization type lithographic printing plate (photopolymerizable lithographic printing plate). An image is formed by a wet brush developing system developing process that exposes the latent image by exposing the lithographic printing plate on which the latent image is formed and brushing with a brush.

  In the exposure process using this laser beam, a blue-violet laser light source, an infrared laser light source, or a laser light source of other wavelengths can be used as a laser light source. Further, an inner drum type, a flat bed type, or a drum type can be used for the laser beam scanning mechanism.

  In this exposure processing using a laser beam, the output of the laser beam when irradiating the image forming unit is set to a predetermined height sufficient to cause a radical photopolymerization reaction to form a latent image based on the image data. The image forming level (DATA DRIVE LEVEL) as an output is set.

  In the exposure process using the laser beam, the non-image forming part is also irradiated with the laser beam. In this exposure process using a laser beam, the latent image is such that the output of the laser beam when irradiating the non-image forming part can be scraped off to the image recording layer of the lithographic printing plate by a developing process using a developer and a brush. The amount of exposure is such that the oxygen dissolved in the image recording layer reacts with radicals generated by irradiation with the laser beam, thereby blocking the influence of the dissolved oxygen in the image recording layer. A preliminary level (BIAS LEVEL) having a predetermined low output suitable for improving reproducibility is used.

  That is, in the exposure processing using this laser beam, the preliminary level (BIAS LEVEL) laser beam irradiated to the non-image forming part causes the radical initiator to react to generate radicals, and the inside of the image recording layer. The remaining oxygen quenches the radicals so that no oxygen remains in the image recording layer, so that the state of sensitivity is increased to suppress the inhibition of the radical polymerization reaction by oxygen.

  Therefore, in this exposure process using a laser beam, a latent image is formed by exposing the image forming unit with an image forming level (DATA DRIVE LEVEL) laser beam while the image recording layer of the planographic printing plate is highly sensitive. Therefore, it is possible to prevent a small dot latent image formed in the image recording layer from being reduced and thinned due to the influence of residual oxygen in the image recording layer, and to perform plate making with good reproducibility of halftone dots.

  In short, in the exposure process using this laser beam, the output of the laser beam when irradiating the image forming unit is switched to a predetermined high output image forming level (DATA DRIVE LEVEL) and non-image forming based on the image data. A latent image is formed on the entire surface of the image recording layer of the lithographic printing plate by performing an exposure operation by switching the output of the laser beam when irradiating the part to a predetermined low output (BIAS LEVEL).

  In the exposure processing using this laser beam, conditions such as the light level (light intensity) and irradiation time of a preliminary level (BIAS LEVEL) laser beam having a predetermined low output for irradiating the non-image forming unit are set. Taking into account the chemical composition of the image recording layer of the lithographic printing plate to be irradiated and the amount of oxygen molecules dissolved in a saturated state in the image recording layer, experiments were conducted in advance for each type of image recording layer. And set corresponding to the image recording layer to be actually exposed.

  In the exposure processing using this laser beam, the image recording layer of the lithographic printing plate subjected to the exposure processing is provided with a sufficiently polymerized latent image portion serving as an image forming portion and the surface side of the image recording layer serving as a non-image forming portion. Only a part is formed with a slightly polymerized part.

Next, in the plate making method of the photopolymerizable lithographic printing plate according to the present embodiment, the lithographic printing plate on which the latent image is formed by the exposure process as described above is developed. In this development process, the developer is applied to the image recording layer of the lithographic printing plate on which the latent image is formed and brushed with a brush, so that only the surface side portion corresponding to the non-image forming portion in the image recording layer of the lithographic printing plate is used. Is slightly scraped off from the support, leaving a sufficiently polymerized portion corresponding to the image forming portion on the support to reveal the latent image to form an image.
(Plate making equipment for photopolymerizable lithographic printing plates)
Next, a photopolymerizable lithographic printing plate making apparatus for carrying out the above-described photopolymerizable lithographic printing plate making method will be described with reference to FIGS.

  Although not shown, the photopolymerization planographic printing plate making apparatus (setter) according to the present embodiment includes a processing unit provided with a plate feeding unit, an exposure unit, a heating unit, and a developing unit, and an exposure unit and a processing unit. It can be comprised with the buffer part provided in between.

  In this photopolymerizable lithographic printing plate making apparatus, the exposure processing step is performed by an inner drum exposure device, and the development processing step is performed by a developing device of a wet alkali brush developing system that brushes in a developer. In this photopolymerizable lithographic printing plate making apparatus, a flat bed type or drum type exposure apparatus may be used in the exposure processing step in addition to the inner drum exposure apparatus.

  As shown in the schematic block diagram of FIG. 1, an inner drum exposure apparatus 10 serving as an exposure apparatus unit used in the photopolymerizable lithographic printing plate making apparatus comprises an arc inner peripheral surface shape (part of a cylindrical inner peripheral surface). The support casing 12 is shaped as a base, and the photopolymerizable lithographic printing plate 14 as a recording medium is supported along the inner peripheral surface of the support casing 12.

  In the inner drum exposure apparatus 10, an unrecorded photopolymerizable lithographic printing plate 14 is supplied by a supply / discharge device for the photopolymerizable lithographic printing plate 14 (not shown) to securely adhere to the inner peripheral surface of the support housing 12. Then, after being engaged in the aligned state, an exposure process is performed, and an operation of discharging the exposed photopolymerizable lithographic printing plate 14 from the support housing 12 to the outside is performed.

  In the inner drum exposure apparatus 10, a spinner mirror device 16 as a scanning unit is disposed at the center of the arc of the support housing 12. The spinner mirror device 16 is configured such that a columnar rotation shaft 18 can be rotated by a motor 20 as a drive source with a central axis as a rotation axis (corresponding to an arc central axis of the support housing 12). A reflecting mirror surface 18A that forms an angle of 45 degrees with respect to the rotation axis is formed at the tip of the rotation axis 18 of the spinner mirror device 16.

  The spinner mirror device 16 as the scanning means is moved and scanned at a constant speed in the axial direction of the center axis of the arc of the support housing 12 (the direction of the arrow C which is the left-right direction in FIG. 1) by a sub-scanning movement means (not shown). Is done. The spinner mirror device 16 is controlled to rotate by a spinner driver 22 and is controlled to move in the sub-scanning direction by a sub-scanning moving unit (not shown).

  As shown in FIG. 1, the inner drum exposure device 10 includes a laser beam emitting device 24 for projecting a light beam on the spinner mirror device 16 side for main scanning on the recording surface of the photopolymerizable lithographic printing plate 14. Provide.

  As shown in FIGS. 1 and 2, the laser beam emitting device 24 is configured to receive an image signal from the central processing unit 26 and output a laser beam modulated based on the image signal.

  In the laser drive circuit of the laser beam emitting device 24, the drive for the image formation level (DATA DRIVE LEVEL) in the drive current controller 30 is performed with respect to the semiconductor laser light source 28 (LED, here using a light emitting diode for blue-violet laser). A circuit for supplying a current and a circuit for supplying a drive current for a reserve level (BIAS LEVEL) in the drive current controller 30 are connected so that each output current is superimposed by the level shifter 33 and then supplied to the laser light source 28. .

  Further, the circuit for supplying the drive current for the image formation level (DATA DRIVE LEVEL) is turned on and off by turning on and off the drive current for the image forming unit based on the image data (IMAGE DATA IN). A modulation element 32 which is a switching element for outputting the laser beam for the image forming unit modulated based on the modulation is provided.

  In this laser drive circuit, a switch 34 for controlling the temperature of the laser light source 28 is provided between the laser light source 28 and the level shifter 33.

  In addition, the drive current controller 30 uses a control signal transmitted from the central processing unit 26 (shown in FIG. 1) to perform predetermined non-corresponding to individual characteristics of the photopolymerizable lithographic printing plate 14 to be subjected to exposure processing. The drive current for the image forming unit is set so as to be output throughout the exposure process.

  The drive current for the non-image forming unit output by the drive current controller 30 can be determined based on the condition of the following formula.

Formula Le <V1 or Le <V1 × α
here,
V1: Experiments and the like for setting an output level at which a latent image is formed so as to be scraped off from the development process of the wet brush development method with respect to an exposure level α: V1 that causes a radical photopolymerization reaction to form a latent image. The coefficient obtained by
Le = Preliminary level Accordingly, in this laser driving circuit, the driving current for the non-image forming unit is always energized from the driving current controller 30 from the start to the end of the exposure process for one photopolymerizable planographic printing plate 14. At the same time, the level shifter 33 displays the drive current for the non-image forming portion and the drive current modulated for the image forming portion by controlling the ON and 0FF of the modulation element 32 corresponding to the exposure timing of the image information. 3, the laser light source 28 is driven in a superposed state.

  In this laser beam emitting device 24, the laser beam corresponding to the image data formed on the photopolymerizable lithographic printing plate 14 as shown in FIG. 4 while the reflecting mirror surface 18A of the spinner mirror device 16 rotates once. And a laser beam for feedback control of the laser power.

  In this laser beam emitting device 24, the laser light emitted from the laser light source 28 is condensed and reflected by the imaging lens system 36 including the aperture as a laser beam on the reflecting mirror surface 18A of the spinner mirror device 16 to be photopolymerizable. Scan exposure is performed on the lithographic printing plate 14.

  In this laser beam emitting device 24, a laser light source 28 is driven by a laser driving circuit, whereby a non-image forming portion of the image recording layer of the photopolymerizable lithographic printing plate 14 is exposed with a relatively weak exposure amount and developed. A latent image to be peeled is formed, and the image forming portion is exposed with a relatively strong exposure amount, and a latent image left by the development processing is formed on the photopolymerizable lithographic printing plate 14 by the development processing.

  In the inner drum exposure apparatus 10, radicals generated when the image recording layer of the photopolymerizable lithographic printing plate 14 is irradiated with the laser beam for exposing the non-image forming portion with a relatively weak exposure amount as described above. The influence of dissolved oxygen in the image recording layer is blocked by reacting with oxygen dissolved in the image recording layer.

  That is, in the exposure process using the inner drum exposure apparatus 10 provided with the laser beam emitting device 24, the preliminary low level (BIAS LEVEL) laser beam irradiated to the non-image forming unit is radically started. The radical is generated by causing the reaction of the agent, and the oxygen remaining in the image recording layer quenches the radical so that no oxygen remains in the image recording layer, thereby inhibiting the radical polymerization reaction by oxygen. It is assumed that the sensitivity is increased.

  In the exposure process using the inner drum exposure apparatus 10 provided with the laser beam emitting device 24, an image forming level having a predetermined high output in a state where the image recording layer of the photopolymerizable lithographic printing plate 14 is made highly sensitive. The latent image is formed by exposing the image forming unit with a (DATA DRIVE LEVEL) laser beam, so that the latent image of the small dots formed in the image recording layer is reduced and thinned by the influence of residual oxygen in the image recording layer. It is possible to make the plate reproducibility with good reproducibility.

  Further, in the laser beam emitting device 24, the laser light source 28 is maintained at a constant temperature by the functions of the Peltier element 40 (PELTIER), the thermistor (THERISTOR) 42, and the temperature controller 44 (TEMP CONTROL) that are temperature control mechanisms. When the thermistor 42 detects that the laser light source 28 has been heated to the limit temperature or more, a detection signal indicating that the laser light source 28 has been heated to the limit temperature or more is transmitted to the temperature control protection unit 38, and the temperature control protection unit 38 38 operates the switch 34 to 0FF to stop the power supply to the laser light source 28 and protect the laser light source 28.

  Further, in the laser beam emitting device 24, a laser power detection value obtained by detecting a light amount of a detection beam branched by disposing a beam splitter 46 in a part of the imaging lens system 36 is detected by a photodiode 48. The power is transmitted to the power control 50, and feedback control is performed so as to keep the laser power of the laser light source 28 at a predetermined output based on the detected value of the laser power.

  Further, in this laser beam emitting device 24, a detection signal indicating that the laser power detected by the photodiode 48 has exceeded the upper limit predetermined value is transmitted to the temperature control protection unit 38, and the temperature control protection unit 38 is switched on and off. 34 is turned off to supply power to the laser light source 28 to protect the laser light source 28.

  In this laser beam emitting device 24, when the output current of the drive current controller 30 exceeds the upper limit predetermined value, the detection signal is transmitted to the temperature control protection unit 38, and the temperature control protection unit 38 opens the switch 34. The laser light source 28 is protected by operating 0FF to stop the power supply to the laser light source 28.

  In the inner drum exposure apparatus 10 that performs the exposure process of the photopolymerization planographic printing plate making apparatus configured as described above, the central processing unit 26 controls the spinner mirror device 16 and the laser beam emitting device 24. An operation of recording an image on the photopolymerizable lithographic printing plate 14 is performed.

  In this photopolymerizable lithographic printing plate making apparatus, when image information to be exposed is input from an input device (not shown) and a command to start exposure processing is transmitted to the central processing unit 26, the central processing unit 26 converts the image information to be exposed. Based on this, the modulation element 32 is driven, the laser light source 28 is controlled to emit light, and laser light modulated based on the image signal is emitted, and reflected by the imaging lens system 36 to the reflecting mirror surface 18A of the spinner mirror device 16. An exposure laser beam is emitted so as to form an image on the photopolymerizable lithographic printing plate 14.

  At the same time, the central processing unit 26 controls the rotation of the motor 20 to rotate the reflecting mirror surface 18A, and reflects the laser beam L incident on the reflecting mirror surface 18A from the laser beam emitting device 24 to reflect the photopolymerizable planographic printing plate. The plate 14 is scanned and exposed in the main scanning direction, and a control signal is transmitted to the spinner driver 22.

  The spinner driver 22 that has received this control signal controls a sub-scanning moving means (not shown), and moves the spinner mirror device 16 in the axial direction of the center axis of the arc of the support housing 12 (the direction of the arrow C that is the left-right direction in FIG. 1). ) To move and scan at a constant speed. As a result, the spinner mirror device 16 is moved in the sub-scanning direction while performing scanning exposure in the main scanning direction by the spinner mirror device 16, so that the two-dimensional recording surface of the photopolymerizable lithographic printing plate 14 is two-dimensional. Processing to record an image is performed.

  As shown in the schematic block diagram of FIG. 5, the developing device of the wet alkaline brush development system that performs the development processing step in the photopolymerizable lithographic printing plate making apparatus forms a latent image in a liquid such as a developing solution. The surface of the image-recording layer of the photopolymerizable lithographic printing plate 14 is brushed with a rotating brush 112 and developed.

  Therefore, in the developing unit 100 shown in FIG. 5, a liquid tank 102 for storing a developer such as alkali is provided, and the photopolymerizable lithographic printing plate is so immersed as to pass through the alkali developer stored therein. 14 conveyance paths are constituted by the guide plate 114 or the like.

  Further, in the developing unit 100, the transport roller pair 104 is disposed on the upstream side of the liquid tank 102 in the transport path of the photopolymerizable lithographic printing plate 14, and the transport roller pair 108 is disposed on the downstream side of the liquid tank 102. Further, a pair of the rotating brush 112 and the auxiliary roller 110 and a pair of conveying rollers 106 are installed in a portion of the conveying path of the photopolymerizable lithographic printing plate 14 passing through the alkaline developer.

  The rotating brush 112 is disposed on the upper side of the conveyance path, and the auxiliary roller 110 is disposed in the vicinity thereof. The auxiliary roller 110 supports the photopolymerizable lithographic printing plate 14 from below during a brushing operation in which the rotating brush 112 rotates while being pressed against the surface of the photopolymerizable lithographic printing plate 14 with a predetermined strength. To be configured.

  In the developing unit 100 configured as described above, the surface of the image recording layer of the photopolymerizable lithographic printing plate 14 by the rotating brush 112 in a state where the photopolymerizable lithographic printing plate 14 is immersed in the alkaline developer in the liquid tank 102. By rubbing with a predetermined strength, the part of the image-recording layer of the photopolymerizable lithographic printing plate 14 which is relatively polymerized only in the surface side part corresponding to the non-image forming part is removed from the support. Then, a development process is performed to reveal the latent image by leaving only a sufficiently polymerized portion corresponding to the image forming portion on the support.

  That is, in the developing unit 100, even when only the surface side portion corresponding to the non-image forming part in the photopolymerizable lithographic printing plate 14 is slightly polymerized, the non-image forming part is removed by brushing with the rotating brush 112. As a result, the photopolymerizable lithographic printing plate 14 can be well made without causing any inconvenience.

  In addition, this invention is not limited to embodiment mentioned above, Of course, it can take other various structures in the range which does not deviate from the summary of this invention.

1 is a perspective view showing a schematic configuration of an inner drum exposure apparatus according to an embodiment of a plate making apparatus for a photopolymerizable lithographic printing plate of the present invention. It is a circuit explanatory drawing which shows the laser beam emission apparatus part concerning embodiment of the plate-making apparatus of the photopolymerizable lithographic printing plate of this invention. It is explanatory drawing which shows the output state of the laser beam radiate | emitted from the laser beam emitting apparatus concerning embodiment of the plate-making apparatus of the photopolymerizable lithographic printing plate of this invention. It is explanatory drawing which shows the output state during the 1 time of the reflective mirror surface of a spinner mirror apparatus in the laser beam radiate | emitted from the laser beam emission apparatus concerning embodiment of the plate making apparatus of the photopolymerizable lithographic printing plate of this invention. It is a schematic block diagram which shows the image development part concerning embodiment of the plate-making apparatus of the photopolymerizable lithographic printing plate of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inner drum exposure apparatus 14 Photopolymerizable lithographic printing plate 24 Laser beam emitting apparatus 26 Central processing unit 28 Laser light source 30 Drive current controller 32 Modulating element 33 Level shifter 34 Switch 36 Imaging lens system 100 Developing section 102 Liquid tank 112 Rotation brush

Claims (3)

For a photopolymerizable lithographic printing plate provided with an image recording layer as an image forming means utilizing a photoradical polymerization reaction on the surface of a support, a light beam modulated based on image data is applied at an image forming level. An exposure processing step of irradiating an image forming portion with an output to cause a radical polymerization reaction to form a latent image by polymerizing;
A photo-polymerization process comprising: a wet-brush development method for exposing the image-recording layer of the exposed photopolymerizable lithographic printing plate to a latent image by applying a developer or brushing in the developer. In the plate making method of the sex lithographic printing plate,
Irradiating the non-image forming portion with a light beam at a preliminary level output that forms a latent image that can be scraped off by a later development processing step on the non-image forming portion in the image recording layer in the exposure processing step. A process for making a photopolymerizable lithographic printing plate characterized by A plate making apparatus for a photopolymerizable lithographic printing plate provided with an image recording layer as an image forming means utilizing a photo radical polymerization reaction on the surface of a support,
A latent image for forming an image by irradiating a photo-radical polymerization reaction by irradiating an image forming portion of the image-recording layer of the photopolymerizable lithographic printing plate with a light beam having an output of an image forming level to form a polymer. An exposure apparatus unit that forms a latent image that does not participate in image formation by irradiating a non-image forming unit in the image recording layer with a low-level light beam at a preliminary level,
By brushing the image recording layer of the photopolymerizable lithographic printing plate subjected to the exposure treatment with a developer, the latent image formed by the light beam at the image forming level is left, and the preliminary level A developing unit that removes the latent image formed by the light beam to make the latent image visible;
An apparatus for making a photopolymerizable lithographic printing plate, comprising: The plate making apparatus for a photopolymerizable lithographic printing plate according to claim 2, wherein the output of the preliminary level of the light beam irradiated to the non-image forming portion is determined by the following equation.
Formula Le <V1 or Le <V1 × α
here,
V1: Experiments and the like for setting an output level at which a latent image is formed so as to be scraped off from the development process of the wet brush development method with respect to an exposure level α: V1 that causes a radical photopolymerization reaction to form a latent image. The coefficient obtained by
Le = Reserve level

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