JP2005313526A - Method and device for folding printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for folding a printing plate which can accurately fold the printing plate without heating and simplify a device/a mechanism and a device for folding the printing plate. <P>SOLUTION: In the method, the printing plate 1 is mounted on a pedestal 2 and a folding base plate 3, a plate fixing block 4 and a folding block 5 are brought down, after the upper surface of the printing plate 1 is pushed by the blocks 4 and 5, the folding block 5 positioned on the side edge 1a side of the printing plate 1 is rotated by about 180° in the rotation direction R around the tip 3a of the folding base plate 3, and the folded printing plate 1 is pressed with the folding base plate 3 inserted between the blocks 4 and 5. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a printing plate folding method and a printing plate folding apparatus that bend side edges of a sheet-like printing plate material in the width direction.

  Conventionally, a printing plate having a resin as a support has been bent at the side edge of the printing plate in order to effectively mount the printing plate on a printing drum. In such a printing plate bending apparatus, a heating means such as a heater is used. The folding angle of the printing plate is kept while it is heated to keep the folding angle (Patent Documents 1 to 4 below). However, the conventional bending method using the heating means has the following problems.

  (1) A heating means is required to maintain the folding angle, and the undulation of the folded portion has occurred due to uneven heating of the printing plate due to temperature variations in the folding width direction. In addition, since the heating is performed, the plastic support expands and contracts due to heat. Further, in a printing plate material having a heat-sensitive image forming layer, the image forming layer reacts with heat.

  (2) In Patent Document 3 below, the printing plate material is folded and pressed after being creased. However, it is necessary to retract a member inside the folding, and it is difficult to maintain the position accuracy of the folding. The mechanism is also complicated.

(3) Since a heat source for heating is required, a control mechanism for keeping the temperature constant is necessary, which increases the number of components and increases the cost. Furthermore, in order to make it ready for immediate use, a standby state in which the temperature is raised to a constant temperature is generally considered, and energy is wasted because the heat source is always consumed even when the device is not used. ing.
Japanese Patent Laid-Open No. 2-102049 JP-A-8-295008 JP 2000-190456 A JP 2002-254601 A

  The present invention provides a printing plate bending method and a printing plate bending apparatus that can accurately bend a printing plate without heating and can simplify the apparatus and mechanism in view of the above-described problems of the prior art. The purpose is to do.

  A schematic process of the printing plate bending method according to the present invention will be described with reference to FIGS. FIG. 1 is a side sectional view for schematically explaining preferred printing plate folding steps (a) to (c) according to the present invention.

  As shown in FIG. 1 (a), the folding base plate 3 is fixed to the pedestal 2 so as to protrude from the tip 2a of the pedestal 2, and the sheet-like printing plate 1 supported by the plastic support is folded into the pedestal 2 and the bent plate 2. It is placed on the base plate 3 and positioned so that the side edge portion 1 a of the printing plate 1 protrudes from the tip end portion 3 a of the bent base plate 3. Next, the plate fixing block 4 and the bending block 5 positioned above as shown by the broken line in the figure are lowered in the downward direction V, and the upper surface of the printing plate 1 is pressed by the plate fixing block 4 and the bending block 5. The bent base plate 3 is preferably made of spring steel and is held by a magnet 6 embedded in the pedestal 2 and has no projection on the surface with which the printing plate 1 contacts.

  Next, as shown in FIG. 1B, when the bending block 5 is rotated in the rotation direction R as indicated by a broken line in the rotation direction R with the front end portion 3a of the bending base plate 3 as a rotation center, the rotation is rotated approximately 180 °. Then, a folding base plate is sandwiched between the plate fixing block 4 and the folding block 5 so that the printing plate 1 is folded in the side edge portion 1a, and the plate fixing block 4 and the folding block are in this folded state. 5, the printing plate 1 and the folded base plate 3 are pressed.

  Next, as shown in FIG. 1C, when the printing plate 1 is taken out after the plate fixing block 4 and the bending block 5 are retracted together in the upward direction V ′, the side edges of the printing plate 1 which are folded over are removed. The portion 1a springs back, and the side edge portion 1a can be bent at a substantially right angle with respect to the printing plate 1.

  As described above, in the printing plate folding method according to the present invention, one side of the sheet-like printing plate material supported by the plastic support is placed on the side of the one side with respect to the plate fixing block and the folding block. Contact is made so that it is located on the edge side, the other surface is brought into contact with the bent base plate, the bent block is rotated by about 180 ° with the tip end portion of the bent base plate as a substantially rotation center, and the bent The printing plate material and the folding base plate are pressed by the plate fixing block and the folding block while the side edges of the printing plate material are folded and folded so as to sandwich the base plate. The side edge of the material is bent.

  According to this printing plate folding method, the printing base material is overlapped and folded at the side edge by sandwiching a folding base plate between the plate fixing block and the folding block, and the printing plate and the folding plate are folded in this overlapping state. Since the base plate is pressed, the side edges of the printing plate material can be accurately folded without heating, and no heating means or the like is required, and the folding base plate is retracted when the folding block is rotated. Since it is not necessary, the bending position accuracy can be improved, and the apparatus and mechanism can be simplified.

  In the printing plate folding method, it is preferable that the pressing force during the pressing can be adjusted at an arbitrary position in the folding width direction of the printing plate material. Thereby, the angle of the bent portion of the printing plate material can be adjusted, and the pressing force can be adjusted at an arbitrary position in the bent width direction, so that the waviness of the bent portion can be eliminated.

  The bent base plate is a metal plate and preferably has a thickness in the range of 0.3 to 0.7 mm. If the thickness of the folding base plate is less than 0.3 mm, the folding base plate will be bent with the rotation of the folding block, which is not preferable. If the thickness exceeds 0.7 mm, the printing plate material will be folded. This is not preferable because it follows the shape of the end portion of the sheet and tends to be bent in two steps. The thickness of the bent base plate is more preferably within a range of 0.4 to 0.5 mm.

  The material of the bent base plate is preferably spring steel. As a result, the spring steel of the folding base plate bends when the folding block is rotated about the tip of the folding base plate as the rotation center, thereby absorbing the concentrated load on the folding part of the printing plate material. In addition, cracking of the printing plate material can be prevented.

  Further, the plate fixing block and the bending block are integrally moved from above the printing plate material downward to contact the printing plate material, and moved upward from below the printing plate material to move the printing plate material. You can be away from. Since the plate fixing block and the folding block can be integrally retracted upward, it is easy to set the printing plate material on the folding mechanism composed of the plate fixing block and the folding block.

The plastic support has a Young's modulus in the range of 4500 to 6500 N / mm ² and a thickness in the range of 100 to 250 μm. The printing plate material has at least a hydrophilic layer and a plastic layer on the plastic support. It is preferable to have a heat-sensitive image forming layer.

The material of the plastic support is preferably polyethylene terephthalate. The thickness of the plastic support is more preferably in the range of 170 to 180 μm. The Young's modulus of the plastic support is more preferably in the range of 5000 to 6000 N / mm ² .

  The printing plate folding apparatus according to the present invention is located on the other surface of the printing plate material, plate fixing means provided so as to come into contact with one surface of the sheet-like printing plate material supported by the plastic support. And a bent base plate provided at the side of the side edge of the one side of the printing plate material relative to the plate fixing means. Bending means that can rotate approximately 180 °, and the bending means is approximately 180 ° in a state where the printing plate material is sandwiched between the bending base plate, the plate fixing means, and the bending means. By rotating, the printing plate material and the folding base plate are moved by the plate fixing means and the folding means while overlapping and folding the side edge portion of the printing plate material so as to sandwich the folding base plate. Press In this way, the side edge portion of the printing plate material is bent.

  According to this printing plate folding apparatus, the printing base material is overlapped and folded at the side edge portion with the folding base plate sandwiched between the plate fixing means and the bending means, and the printing plate and the folding plate are folded in this overlapped state. Since the base plate is pressed, the side edges of the printing plate material can be accurately folded without heating, and no heating means or the like is required and the folding base plate is retracted when the folding means is rotated. Since it is not necessary, the bending position accuracy can be improved, and the apparatus and mechanism can be simplified.

  The printing plate bending apparatus preferably includes a pressing force adjusting mechanism capable of adjusting a pressing force at the time of pressing at an arbitrary position in a bending width direction of the printing plate material. By this pressing force adjusting mechanism, the angle of the bent portion of the printing plate material can be adjusted, and the pressing force can be adjusted at an arbitrary position in the bending width direction, so that the waviness of the bent portion can be eliminated.

  The bent base plate is a metal plate and preferably has a thickness in the range of 0.3 to 0.7 mm. If the thickness of the folding base plate is less than 0.3 mm, the folding base plate will be bent along with the rotation of the folding means, and if it exceeds 0.7 mm, the printing plate material will be folded. This is not preferable because it follows the shape of the end portion of the sheet and tends to be bent in two steps. The thickness of the bent base plate is more preferably within a range of 0.4 to 0.5 mm.

  The material of the bent base plate is preferably spring steel. As a result, the spring steel of the folding base plate bends when the folding means is rotated about the tip of the folding base plate as the rotation center, thereby absorbing the concentrated load on the folding portion of the printing plate material. In addition, cracking of the printing plate material can be prevented.

  The bent base plate is preferably held by a magnet. Since the printing plate material is always in contact with the upper surface of the folded base plate, if there are protrusions, the printing plate material may be scratched, or the edge of the printing plate material may be caught when set. By holding it with a magnet, there is no protrusion, and it is possible to eliminate such problems.

  Further, it is preferable that the plate fixing means and the bending means constitute a bending mechanism integrally and are provided above the printing plate material so as to be close to and away from the printing plate material. Since the plate fixing means and the folding means can be integrally retracted upward, it is easy to set the printing plate on the folding mechanism.

  Moreover, it is preferable to provide a fall prevention mechanism that can hold and fix the bending mechanism at a holding position above the printing plate material. With the fall prevention mechanism, the folding mechanism is retracted upward and is held and fixed at the holding position, and both hands can be used for setting the printing plate material, so that it is possible to improve workability and prevent damage to the printing plate material, Safety during work can be secured.

The plastic support has a Young's modulus in the range of 4500 to 6500 N / mm ² and a thickness in the range of 100 to 250 μm. The printing plate material has at least a hydrophilic layer and a plastic layer on the plastic support. It is preferable to have a heat-sensitive image forming layer.

The material of the plastic support is preferably polyethylene terephthalate. More preferably, the plastic support has a thickness in the range of 170 to 180 μm. The Young's modulus of the plastic support is more preferably in the range of 5000 to 6000 N / mm ² .

  According to the printing plate folding method and the printing plate folding apparatus of the present invention, the printing plate can be accurately folded without heating, and the apparatus and mechanism can be simplified.

  The best mode for carrying out the present invention will be described below with reference to the drawings. FIG. 2 is a perspective view showing the overall appearance of the printing plate folding apparatus according to the present embodiment.

  As shown in FIG. 2, the printing plate bending apparatus includes a bending mechanism unit 11 that is surrounded by a cover member 11a and bends a sheet-like printing plate, and an operation switch unit that sets the number of times of bending and operating time and has a bending start switch. 12, a pedestal 13 inclined to place the printing plate, a plate holding lever 14 that is ready to bend when pulled up and can set and take out the printing plate when pulled down; The electrical equipment box 15 in which the switch 20 is disposed, the installation base 16 placed on the installation surface, and the support frame 17 that stands upright from the installation base 16 and is inclined so as to support the pedestal 13 and the bending mechanism unit 11 are provided.

  The pedestal 13 has a built-in suction mechanism for sucking when the printing plate is placed, and the suction mechanism has a suction size changeover switch 18 and a foot switch 19 for turning on / off the suction.

  Next, the bending mechanism portion 11 of the printing plate bending apparatus shown in FIG. 2 will be described with reference to FIGS.

  FIG. 3 is a perspective view of the bending mechanism 11 of the printing plate bending apparatus of FIG. 2 as viewed from the back side with the cover member 11a removed. FIG. 4 is a perspective view of a main part showing a state in which the plate fixing block 24 and the bending block 25 of the bending mechanism unit 11 of FIG. 3 are retracted upward. FIG. 5 is a side view showing a state in which the plate fixing block 24 and the bending block 25 of the bending mechanism unit 11 of FIG. 3 are retracted upward. FIG. 6 is a side view showing a state in which the plate fixing block 24 and the bending block 25 of the bending mechanism unit 11 of FIG. 3 are lowered and press the printing plate.

  As shown in FIGS. 3 to 6, the bending mechanism unit 11 includes a plate fixing block 24 that fixes the sheet-like printing plate 1 (FIG. 5) placed on the base 13 shown in FIG. A bending block 25 that rotates about 180 ° around the rotation shaft 32 so that the printing plate 1 fixed by the fixing block 24 is folded at the side edge portion 1a, a gear 31 connected to the rotation shaft 32, a plate fixing block 24, And a support portion 21 that supports the bending block 25 and rotatably supports the rotating shaft 32.

  As shown in FIGS. 5 and 6, when the plate pressing lever 14 is pulled up in the rotation direction S, a lever is moved at a fulcrum 14 a provided below the pedestal 13, and a force acts on the action portion 21 e below the support portion 21. As a result, the support portion 21 is guided by the roller 21b in the groove 21a of the support portion 21 and the rollers 21c and 21d that are in contact with the side surface of the support portion 21 on the plate pressing lever 14 side, while being substantially downwardly r in the figure. When the plate holding lever 14 is pulled down in the rotation direction S ′ while moving together with the fixing block 24 and the folding block 25, the support portion 21 moves together with the plate fixing block 24 and the bending block 25 in a substantially upward direction r ′ in the figure. It has become.

  As shown in FIG. 5, when the plate pressing lever 14 is lifted in the rotation direction S and the support portion 21 is lowered substantially downward r in the figure, the plate fixing block 24 and the bending block 25 are pedestaled as shown in FIGS. 13, approaches and presses the printing plate 1 on the pedestal 13, and the gear 31 connected to the rotary shaft 32 also descends, and the gear 31 meshes with another gear 33 disposed below the pedestal 13. It is like that.

  Further, as shown in FIG. 6, when the plate holding lever 14 is pulled down in the rotation direction S ′ from the state in which the plate fixing block 24 and the bending block 25 are in contact with and pressed against the printing plate 1 on the pedestal 13, FIG. As shown in FIG. 5, the plate fixing block 24 and the folding block 25 move away from the base 13 and move upward, so that the printing plate can be set or removed.

  Further, when the gear 33 disposed below the pedestal 13 is rotationally driven via a rotating shaft 33a driven by a motor (not shown) that is turned on and off by the operation switch unit 12 of FIG. 6, the folding block 25 is rotated approximately 180 ° in the rotation direction R through the gear 31 and the rotating shaft 32 engaged with each other, and the 180 ° rotated state is maintained and sandwiched between the plate fixing blocks 24. The printing plate 1 is pressed.

  Further, the plate fixing block 24 and the bending block 25 extend along the width direction W of the pedestal 13 in FIG. 2, and a gear 31 and a rotation shaft 32 are provided at both ends thereof, and the rotation shaft 33a is also formed in the width direction W. The gear 33 is connected to both ends.

  Further, the pedestal 13 in FIG. 2 is generally formed of a metal material such as aluminum in a substantially rectangular plane shape, and the tip side (the back side in FIG. 2) is made of spring steel as shown in FIGS. The folding base plate 23 extends along the width direction W, and the base 13 and the folding base plate 23 are fixed so as to form the same plane. The folding base plate 23 is fixed by a magnet embedded on the pedestal side as shown in FIG.

  As shown in FIGS. 4 to 6, the distal end portion 23 a of the bent base plate 23 fixed to the pedestal 13 protrudes from the end surface 13 a of the pedestal 13 so that the bending block 25 does not contact the distal end portion 23 a. It is a positional relationship protruding. The bending block 25 rotates about the rotation shaft 32. The central axis of the rotation shaft 32 is substantially coincident with the distal end portion 23a of the folding base plate 23, and the bending block 25 has the distal end portion 23a. It rotates in the rotation direction R as a substantial rotation center.

  The bent base plate 23 made of a metal plate preferably has a thickness in the range of 0.3 to 0.7 mm. If the thickness of the folding base plate 23 is less than 0.3 mm, the folding base plate 23 is bent with the rotation of the folding block 25, which is not preferable. If the thickness exceeds 0.7 mm, the printing plate 1 is bent. It is not preferable because it follows the tip 23a of the base plate 23 and tends to be bent in two steps. The thickness of the bent base plate 23 is more preferably in the range of 0.4 to 0.5 mm. Further, the material of the bent base plate 23 is spring steel, and when the bending block 25 rotates about the tip end portion 23a of the bent base plate 23 as a rotation center, the spring steel is bent, The concentrated load on the bent portion of the printing plate 1 can be absorbed, and cracking of the printing plate 1 can be prevented.

  The lower part of the bending block 25 is configured as a thin part 25a having a small thickness in the longitudinal direction (depth direction) of the base 13 shown in FIGS. 2, 5, and 6, and the thickness of the thin part 25a is a bending base. The protruding length of the tip 23a of the plate 23 is smaller than the protruding length. As a result, when the folding block 25 rotates approximately 180 °, the folding block 25 does not come into contact with the end surface 13a of the base 13, and the thin portion 25a faces the lower surface of the distal end portion 23a of the folding base plate 23 ( (Refer FIG.8 (f)).

  Next, a pressing force adjusting mechanism that adjusts the pressing force when the printing plate 1 is pressed between the thin portion 25a and the plate fixing block 24 after the bending block 25 is rotated approximately 180 ° in the rotation direction R is illustrated. This will be described with reference to FIG. FIG. 7 is a rear view (a) and a partially enlarged view (b) of the plate fixing block 24 provided with the pressing force adjusting mechanism as seen from the rear side shown in FIGS.

  As shown in FIG. 7A, the plate fixing block 24 extends in the width direction W of the base 13 of FIG. 2, but is divided into an upper block 24a and a lower block 24b. In the pressing force adjusting mechanism shown in FIG. 7, the upper block 24a and the lower block 24b are screwed together by screw holes 24c provided at a plurality of positions in the width direction W, and are screwed at a plurality of positions in the width direction W to the lower block 24b. It is configured by providing a hole 24d.

  As shown in FIGS. 7A and 7B, the bolts 24f are inserted from the through holes formed in the upper block 24a and screwed into the screw holes 24c of the lower block 24b, whereby the blocks 24a and 24b are screwed together. . Further, the set screw 24g is screwed into each screw hole 24d from the lower surface of the lower block 24b, and the protruding amount from the mating surface 24e of both the blocks 24a and 24b is adjusted for each set screw 24g, so that the entire plate fixing block 24 is The height h is adjusted in the width direction W. Thus, since the overall height h of the plate fixing block 24 changes in the width direction W, the pressing force when pressing the printing plate 1 between the plate fixing block 24 and the thin portion 25a of the bending block 25 changes. The pressing force can be adjusted.

  Next, a fall prevention mechanism for holding and fixing the bending mechanism portion 11 moved upward as shown in FIG. 5 at the upper holding position will be described with reference to FIG. FIG. 8 is a schematic diagram (a) and a partially enlarged view (b) showing a fall prevention mechanism of the bending mechanism section 11.

  As shown in FIG. 8A, the magnet 40 is fixed below the support portion 21 of the bending mechanism section 11, and when the bending mechanism section 11 moves substantially upward r as shown in FIGS. The magnet 40 is attracted to the fixed portion 41 fixed to the pedestal 13 side. By this fall prevention mechanism, when the bending mechanism portion 11 is retracted upward, it is held and fixed at the holding position, and both hands can be used for setting the printing plate 1, thereby improving workability and preventing damage to the printing plate 1. It becomes possible and can secure safety during work.

  Further, as shown in FIGS. 8A and 8B, the fixed portion 41 is provided with a ball plunger 41a, and a spring in the ball plunger 41a is positioned at a position where the magnet 40 is attracted to the fixed portion 41. The small ball 41 b urged outward by 41 c enters the hemispherical recess 21 f on the side surface of the support portion 21. By this ball plunger 41a, the bending mechanism 11 is moved upward as shown in FIG. 5, and the positioning when the magnet 40 is attracted to the fixing part 41 and fixed at the holding position is reliably performed.

  Next, a bending process of bending the side edge portion of the printing plate having the plastic support by the printing plate bending apparatus shown in FIGS. 2 to 8 will be described with reference to FIGS. 9 (a) to 9 (f). FIGS. 9A to 9F are side views of the main part for explaining the folding steps (a) to (f) in which the side edge portion of the printing plate is folded by the printing plate folding apparatus of FIGS. 2 to 8. .

  First, for example, when the plate pressing lever 14 is pulled down in the rotation direction S ′ from the state of FIG. 6, the bending mechanism portions 11 such as the plate fixing block 24 and the bending block 25 move substantially upward r ′, and FIGS. As shown in (a), the sheet-like printing plate 1 is in a released state, and the sheet-like printing plate 1 is positioned so that the front end of the side edge 1a protrudes from the front end 23a of the bent base plate 23 as shown by the broken line. By operating the foot switch 19 of 2, the suction mechanism built in the pedestal 13 is operated to fix the printing plate 1 to the pedestal 13. At this time, the bending mechanism unit 11 is fixed at the position shown in FIG. 9A by the fall prevention mechanism shown in FIG.

  Next, when the plate pressing lever 14 is pulled up in the rotation direction S from the state of FIG. 5, the fixing by the magnet 40 of FIG. 8 is released, and the bending mechanism portion 11 moves substantially downward r to move the plate fixing block 24 and the bending block. 25, the plate fixing block 24 comes into contact with the printing plate 1 as shown in FIGS. 6 and 9B, and the thin portion 25a of the bending block 25 comes into contact with the protruding side edge portion 1a of the printing plate 1.

  Next, when the motor (not shown) is rotated by turning on the operation switch unit 12 in FIG. 2, the rotary shaft 32 rotates through the rotary shaft 33a, the gear 33, and the gear 31 as shown in FIGS. As a result, the bending block 25 starts to rotate in the rotation direction R around the tip end portion 23a of the base plate 23 as a substantially center of rotation, as shown in FIG. 9 (c), 45 °, as shown in FIG. 9 (d). The thin-walled portion 25a bends the side edge portion 1a of the printing plate 1 while rotating by 90 ° and 135 ° as shown in FIG.

  Then, when the bending block 25 is rotated by 180 ° as shown in FIG. 9 (f), the folding block 25 is positioned downward so as to face the plate fixing block 24, and the printing plate 1 side is located between the thin portion 25 a and the plate fixing block 24. The edge portion 1a is in a folded state with the front end portion 23a of the folded base plate 23 sandwiched therebetween (see FIG. 1B).

  By holding the folded state of the printing plate 1 of FIG. 9F, the side edge portion 1a of the printing plate 1 folded by the thin portion 25a is pressed. Next, by rotating the motor (not shown) in the reverse direction, the bending block 25 is returned from the state shown in FIG. 9F to the state shown in FIGS. 6 and 9B, and then the plate pressing lever 14 is rotated. When pulled down to S ′, the bending mechanism 11 moves substantially upward r as shown in FIGS. 5 and 9A and is fixed by the magnet 40 shown in FIG. 8, and the printing plate 1 is removed from the base 13. . When the side edge portion 1a folded over the printing plate 1 is spring-backed, the side edge portion 1a can be bent at a substantially right angle with respect to the printing plate 1 as shown in FIG.

  As described above, according to the printing plate bending apparatus shown in FIGS. 2 to 8, the folding base plate 23 is sandwiched between the plate fixing block 24 and the folding block 25 and the printing plate 1 is overlapped on the side edge portion 1a. Since the printing plate 1 and the folding base plate 23 are pressed in the folded and folded state, the side edge portion 1a of the printing plate 1 can be accurately folded without heating, and no heating means or the like is required. Since it is not necessary to retract the folding base plate 23 that is a member inside the printing plate when the folding block 25 is rotated, the accuracy of the folding position can be improved, and the apparatus and mechanism can be simplified. .

  Further, the bending angle can be adjusted by changing the pressing force by the pressing force adjusting mechanism shown in FIG. 7, and the pressing force can be adjusted at an arbitrary position in the width direction W of the printing plate 1. Can eliminate undulations.

  In addition, since the printing plate 1 is always in contact with the upper surface of the bent base plate 23, if there is a protrusion, scratches on the printing plate and catching of the printing plate edge portion during setting occur. By holding and fixing the bent base plate 23 with a magnet, there are no protrusions, and it is possible to prevent such scratches from occurring. In addition, it is not preferable to hold and fix the bent base plate 23 with an adhesive, a double-sided tape or the like because workability during assembly deteriorates. In addition, since no heating means is required, a heating control mechanism or the like is unnecessary, which does not increase the number of parts or increase the cost, and does not require a standby state in which the temperature is raised to a constant temperature. There is no power consumption and no energy is wasted, and the image forming layer does not react with heat on the printing plate.

  Next, a preferred printing plate applied to the printing plate folding method of FIG. 1 and the printing plate folding apparatus of FIGS. 2 to 9 will be described with reference to FIG. FIG. 10 is a cross-sectional view schematically showing the layer structure of the printing plate in the present embodiment.

  As shown in FIG. 10, the sheet-like printing plate 1 has at least a hydrophilic layer 51 and a heat-sensitive image forming layer 52 on a plastic support 50. The printing plate 1 is wound around, for example, a drum of a printing plate manufacturing apparatus, and after the drum is rotated and image data is scanned and exposed by a light source to record an image, the side edge portion 1a is illustrated as described above. After being bent as in 1 (c), it is effectively mounted on the plate cylinder of the printing press using the bent portion.

  Examples of the plastic support 50 of the printing plate 1 include polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyimide, polyamide, polycarbonate, polysulfone, polyphenylene oxide, and cellulose esters. Particularly preferred are polyester films such as polyethylene terephthalate and polyethylene naphthalate.

For the plastic support 50, polyethylene terephthalate is particularly preferable from the viewpoint of transportability, ease of handling, etc. In the printing plate preparation apparatus, if the thickness of the plastic support is too thin or too thick, it is difficult to form a roll and there is a problem in transportability. In addition, if it is too thin, there is a problem that it is not strong enough to bend when it is carried to a printing machine in the next process, and the thickness of the plastic support 50 is preferably 100 to 250 μm from the viewpoint of transportability and ease of handling. Preferably it is 170-180 micrometers. Moreover, the plastic support 50 preferably has a Young's modulus in the range of 4500 to 6500N / mm ^2, and more preferably in the range of 5000 to 6000 N / mm ^2.

  The hydrophilic layer 51 of the printing plate 1 is a layer having a function of not depositing printing ink at the time of printing. As a material for forming the hydrophilic layer 51, an organic hydrophilic polymer is crosslinked or pseudo-crosslinked. Organic hydrophilic matrix structures obtained, inorganic hydrophilic matrix structures obtained by sol-gel conversion consisting of hydrolysis and condensation reactions of polyalkoxysilane, titanate, zirconate or aluminate, metal oxides and the like are preferably used. . The hydrophilic layer 51 preferably includes metal oxide fine particles, and examples thereof include colloidal silica, alumina sol, titania sol, and other metal oxide sols.

  The heat-sensitive image forming layer 52 of the printing plate 1 is a layer capable of forming an image by heating, and contains heat-melting fine particles and / or heat-fusible fine particles. The heat-meltable fine particles are fine particles formed of a material that has a low viscosity when melted, and is generally classified as a wax, among thermoplastic materials. The heat-fusible fine particles include thermoplastic hydrophobic polymer polymer fine particles, and there is no specific upper limit for the softening temperature of the thermoplastic hydrophobic polymer polymer particles. The temperature is preferably lower than the decomposition temperature of the fine particles.

  As described above, the best mode for carrying out the present invention has been described. However, the present invention is not limited to these, and various modifications are possible within the scope of the technical idea of the present invention. For example, a pressing force adjusting mechanism similar to that shown in FIG.

It is a sectional side view for demonstrating schematically the bending process (a)-(c) of the preferable printing plate by this invention. It is a perspective view which shows the whole external appearance of the printing plate bending apparatus by this Embodiment. It is the perspective view which looked at the bending mechanism part 11 of the printing plate bending apparatus of FIG. 2 from the back side in the state which removed the cover member 11a. It is a principal part perspective view which shows the state which the plate fixing block 24 and the bending block 25 of the bending mechanism part 11 of FIG. 3 retracted upwards. FIG. 4 is a side view showing a state in which a plate fixing block 24 and a bending block 25 of the bending mechanism section 11 of FIG. 3 are retracted upward. It is a side view which shows the state which the plate fixing block 24 and the bending block 25 of the bending mechanism part 11 of FIG. FIG. 5 is a rear view (a) and a partially enlarged view (b) of the plate fixing block 24 provided with a pressing force adjusting mechanism as seen from the rear side shown in FIGS. It is the schematic diagram (a) which shows the fall prevention mechanism of the bending mechanism part 11, and its partial enlarged view (b). It is a principal part side view for demonstrating the bending process (a) thru | or (f) which bends the side edge part of a printing plate with the printing plate bending apparatus of FIG. 2 thru | or FIG. It is sectional drawing which shows typically the layer structure of the printing plate in this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printing plate 1a Side edge part 2 Base 3 Bending base board 3a Tip part 4 Plate fixing block 5 Bending block 6 Magnet 11 Bending mechanism part (bending mechanism)
13 Base 14 Plate holding lever 21 Support portion 23 Bending base plate 23a Tip portion 24 Plate fixing block (plate fixing means)
24a Upper block 24b Lower block 24f Bolt 24g Set screw 25 Bending block (bending means)
25a Thin-walled portion 31 Gear 32 Rotating shaft 33 Gear 40 Magnet 41 Fixed portion 41a Ball plunger 50 Plastic support 51 Hydrophilic layer 52 Thermosensitive image forming layer R Rotating direction W Width 13 of base 13 Overall height r Nearly upper r 'Nearly below

Claims (22)

One side of the sheet-like printing plate material supported by the plastic support is brought into contact with the plate fixing block and the folding block so that the folding block is positioned on the side edge side of the one side, and the other side Is brought into contact with the bent base plate,
The plate is fixed while the folding block is rotated by about 180 ° with the front end of the bent base plate as a center of rotation, and the side edges of the printing plate material are folded and folded so as to sandwich the bent base plate. A printing plate folding method, wherein a side edge portion of the printing plate material is folded by pressing the printing plate material and the folding base plate between the block and the folding block. 2. The printing plate bending method according to claim 1, wherein the pressing force at the time of pressing can be adjusted at an arbitrary position in the bending width direction of the printing plate material. The printing plate bending method according to claim 1 or 2, wherein the folding base plate is a metal plate and has a thickness in a range of 0.3 to 0.7 mm. 4. The printing plate folding method according to claim 3, wherein the thickness of the folding base plate is within a range of 0.4 to 0.5 mm. The printing plate bending method according to any one of claims 1 to 4, wherein a material of the folding base plate is spring steel. The plate fixing block and the bending block are integrally moved downward from above the printing plate material to contact the printing plate material, and moved upward from below the printing plate material to leave the printing plate material. The printing plate bending method according to claim 1, wherein the printing plate is bent. The plastic support has a Young's modulus in the range of 4500 to 6500 N / mm ² and a thickness in the range of 100 to 250 μm.
The printing plate bending method according to claim 1, wherein the printing plate material has at least a hydrophilic layer and a heat-sensitive image forming layer on the plastic support. The printing plate bending method according to claim 1, wherein the plastic support is made of polyethylene terephthalate. The printing plate bending method according to any one of claims 1 to 8, wherein the plastic support has a thickness in a range of 170 to 180 µm. 10. The printing plate bending method according to claim 1, wherein a Young's modulus of the plastic support is in a range of 5000 to 6000 N / mm ² . Plate fixing means provided so as to come into contact with one surface of a sheet-like printing plate material supported by a plastic support;
A folded base plate provided on the other side of the printing plate material;
Bending means provided so as to be positioned closer to the side edge portion of one side of the printing plate material than the plate fixing means, and capable of rotating about 180 ° about the front end portion of the folding base plate as a rotation center. Prepared,
The folding base plate is sandwiched by rotating the folding means approximately 180 ° with the printing plate material sandwiched between the folding base plate and the plate fixing means and the folding means. The side edge of the printing plate material is folded by pressing the printing plate material and the folding base plate with the plate fixing means and the folding means while folding the side edge of the printing plate material. A printing plate bending apparatus characterized by that. The printing plate bending apparatus according to claim 11, further comprising a pressing force adjusting mechanism capable of adjusting a pressing force at the time of pressing at an arbitrary position in a bending width direction of the printing plate material. The printing plate bending apparatus according to claim 11 or 12, wherein the folding base plate is a metal plate and has a thickness in a range of 0.3 to 0.7 mm. The printing plate folding apparatus according to claim 13, wherein the thickness of the folding base plate is in a range of 0.4 to 0.5 mm. The printing plate bending apparatus according to any one of claims 11 to 14, wherein a material of the folding base plate is spring steel. The printing plate bending apparatus according to claim 11, wherein the bending base plate is held by a magnet. 17. The plate fixing means and the bending means constitute a bending mechanism as a unit, and are provided above the printing plate material so as to be close to and away from the printing plate material. The printing plate bending apparatus according to any one of the above. The printing plate bending apparatus according to claim 17, further comprising a fall prevention mechanism that allows the bending mechanism to be held and fixed at a holding position above the printing plate material. The plastic support has a Young's modulus in the range of 4500 to 6500 N / mm ² and a thickness in the range of 100 to 250 μm.
20. The printing plate bending apparatus according to claim 12, wherein the printing plate material has at least a hydrophilic layer and a heat-sensitive image forming layer on the plastic support. 20. The printing plate bending apparatus according to claim 11, wherein the plastic support is made of polyethylene terephthalate. 21. The printing plate bending apparatus according to claim 11, wherein the plastic support has a thickness in a range of 170 to 180 [mu] m. Printing plate folding device according to any one of claims 11 to 21, wherein the Young's modulus of the plastic support is in the range of 5000 to 6000 N / mm ^2.

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