JP2005074670A - Method for mounting printing plate on offset rotary press - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for mounting a printing plate on an offset rotary press by which successful initial position registering is obtained by removing a deflection generated in the printing plate due to a space between a chucking side vice and the printing plate. <P>SOLUTION: In the method for mounting a printing plate on the offset rotary press, a spacer is inserted into the space generated between the vice and the printing plate when the printing plate is inserted into the chucking side vice installed on a plate cylinder and thereby, the deflection of the printing plate generated by the space is removed to secure the successful initial position registering. The spacer is selected from among the types d, N, U and V. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a printing method in an offset rotary printing press, and more particularly to a printing method in an offset rotary printing press that can obtain a good initial registration by removing the deflection of the printing plate.

  An offset rotary printing press that prints on a sheet of paper may perform printing using a printing plate called a “flexible base plate”. The feature of the printing plate is that paper or film is applied to the base of the printing plate, and it is cheaper than the aluminum base plate that has been used in the past, and it is made by analog plate making. It is widely used mainly in light printing because it can produce printing plates with fewer steps than aluminum-based plates, and is suitable for printing with small lots and short delivery times.

  At present, flexible base plates are also used in high-grade color printing for the purpose of reducing the cost of printing materials and responding to the increasing short lot short delivery time.

  However, since the flexible base plate uses soft materials such as paper and film as the base, aluminum base plates that use hard materials as the base, such as partial distortion in the initial register, are used. It may cause unique problems that cannot be seen.

  A mechanism for causing partial distortion in the initial registration of the flexible base plate will be described with reference to the drawings, together with a plate-hanging method in an offset rotary printing press.

  FIG. 6 is a perspective view showing an aspect in which a printing plate is mounted on a plate cylinder. In the printing on the rotary offset printing press, after the printing plate 8 is inserted into the holding side vise 10 provided in the plate cylinder 9, the holding side vise is closed to fix the holding side of the printing plate. Next, after winding the printing plate along the circumference of the plate cylinder and inserting the printing plate into the holding butt side vise 11 provided on the plate cylinder, the holding butt side vise is closed, and the printing plate's holding butt side The procedure is to fix.

  In addition, as shown in the sectional view of the holding-side vise in FIG. 7, the holding-side vise 2 has an interval X provided for inserting a printing plate. The interval is closed in the plate cylinder direction (illustrated by an arrow) after the printing plate 3 is inserted, so that the printing plate is fixed.

  When the printing plate 3 is inserted and fixed at the gap X of the holding side vise 2, since the base material is a hard material in the case of the aluminum base plate, the gap is as shown in the illustrated printing plate 3. There is almost no deflection. Therefore, when holding the plate, as shown in the cross-sectional view of the printing plate near the holding side vise in FIG. 8, the holding side 12 of the printing plate tends to approach parallel to the width direction of the plate cylinder 9. As shown in the print image 14 printed on the printing paper 13 in FIG. 9, a good initial register can be obtained.

  On the other hand, in the case of the flexible base plate, since a soft material is applied to the base, the printing plate 15 is likely to bend at an interval X as shown in the cross-sectional view of the holding side vise in FIG. Accordingly, when holding the plate, the holding side of the printing plate 16 tends to bend with respect to the width direction of the plate cylinder 9 as shown in the cross-sectional view of the printing plate near the holding side vise in FIG. It is easy to obtain an initial register in which a partial distortion as shown in a print image 17 printed on the print paper 13 is generated.

  Conventionally, in order to prevent partial distortion of the initial register due to this deflection of the printing plate, measures such as pressing the printing plate in the direction of the plate cylinder with a pressure roll have been adopted when stenciling the plate ( For example, see Patent Document 1.)

However, in order to prevent partial distortion of the initial register more effectively, the printing plate is not pressed in the direction of the plate cylinder by the pressure roll, but the gap between the holding side vise and the printing plate is eliminated, It seems that a printing method that can eliminate the deflection of the printing plate is effective, but until now there was no such printing method.
JP-A-7-304160

  SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problem, and removes the deflection of the printing plate caused by the holding side vise and the interval between the printing plates, and provides a printing method in an offset rotary printing press that provides a good initial registration. Is to provide.

  As a result of intensive research in view of the above, the present inventors have invented a plate-hanging method in an offset rotary printing press according to the present invention.

  That is, the printing method in the rotary offset printing press of the present invention is generated by inserting a spacer between the vise and the printing plate generated when the printing plate is inserted into the holding side vise provided in the plate cylinder. It is characterized in that the deflection of the printing plate is removed and a good initial register is obtained.

  In the present invention, the spacer is selected from d-type, N-type, U-type and V-type spacers.

  Further, the printing method in the rotary offset printing press according to the present invention is such that the shape on the holding side of the printing plate is processed into a shape selected from d-type, N-type, U-type and V-type, so that the holding-side vise and the printing plate It is characterized in that a good initial register can be obtained by removing the deflection of the printing plate caused by the interval.

  As described above, the method for removing the deflection of the printing plate caused by the holding side vise and the printing plate spacing in the present invention more effectively prevents the initial registration partial distortion that occurs in the flexible base plate. I can do it now.

  Hereinafter, a printing method in an offset rotary printing press according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing an embodiment of the present invention in which spacers are inserted between the holding side vise and the printing plate. Since the d-type spacer 1 is inserted into the gap X of the holding side vise 2, there is no gap between the vise and the printing plate 3, and pressure is applied in the plate cylinder direction by the spacer. Is closely attached to the plate cylinder side.

  In the above-described state, even in the flexible base plate in which the soft material is applied to the base, the deflection generated at the interval X is removed, so that the sectional view of the printing plate near the holding side vise in FIG. As shown in the figure, since the holding side 12 of the printing plate tends to approach parallel to the width direction of the plate cylinder 9, a good initial registration is obtained as shown in the print image 14 printed on the printing paper 13 in FIG. I can do it.

  Since the width of the gap X of the holding side vise 2 shown in FIG. 1 may vary depending on the specifications of the offset rotary printing press, it is preferable to select the shape of the spacer as appropriate. For example, when the interval is wide, a strong pressure is required in the direction of the plate cylinder in order to remove the deflection. Therefore, the d-type spacer 1 shown in FIG. 1 that generates a relatively strong pressure or the N-type spacer 1 shown in FIG. A mold spacer 4 or the like is suitable.

  On the other hand, when the interval is narrow, the pressure in the plate cylinder direction for removing the deflection may be weak. Therefore, the U-shaped spacer 5 shown in FIG. 3 that generates a relatively weak pressure or the V-type shown in FIG. A spacer 6 or the like is suitable.

  In addition, the depth Y provided for inserting the printing plate in the holding side vise 2 shown in FIG. 1 may be different depending on the specifications of the offset rotary printing press. Is preferred. In addition, when the depth of the holding side vise is shallow, and there is a concern that the spacer may fall off during printing, a mode in which the spacer is directly attached to the printing plate is also preferable.

  Further, the offset rotary printing press has a printing plate thickness suitable for the gripper side vise 2, for example, 0.24 mm, 0.30 mm, 0.24 mm, and 0.30 mm are commonly used. is there. Therefore, as for the thickness of the spacer, select a thickness that matches the specifications of the printing machine, such as referring to the value obtained by dividing the thickness of the printing plate 3 actually used from the specified thickness of the printing plate of the holding side vise. It is preferable to do.

  In addition, by inserting a spacer, it may be possible to slightly exceed the specified thickness of the printing plate in the holding side vise 2, so that the spacer material is relatively soft, such as a film or paper, with cushioning properties. It is preferable to select a material.

  FIG. 5 is a cross-sectional view showing an embodiment in which the shape of the printing plate holding side of the present invention is processed. Since the printing plate 7 processed into a d-type is inserted into the gap X of the holding side vise 2, there is no gap between the vise and the printing plate and pressure is applied in the plate cylinder direction. Is closely attached to the plate cylinder side.

  In the above-described state, even in the flexible base plate in which the soft material is applied to the base, the deflection generated at the interval X is removed, so that the sectional view of the printing plate near the holding side vise in FIG. As shown in the figure, since the holding side 12 of the printing plate tends to approach parallel to the width direction of the plate cylinder 9, a good initial registration is obtained as shown in the print image 14 printed on the printing paper 13 in FIG. I can do it.

  The width of the gap X and the depth Y of the holding side vise 2 shown in FIG. 5 are different depending on the specifications of the offset rotary printing press, so the shape of the processed portion of the printing plate 7 (other than the d-type is not shown) ), And the length is preferably adjusted as in the case of the spacer.

  Furthermore, since the prescribed thickness of the printing plate suitable for the gripping side vise 2 differs depending on the specifications of the rotary offset printing press, the thickness of the printing plate 7 should be selected in accordance with the specifications of the printing press as with the spacer. Is preferred.

  Also, depending on the thickness of the printing plate 7, it may be possible to slightly exceed the specified thickness of the printing plate in the holding side vise 2, but the flexible base plate is made of a relatively soft material with cushioning properties such as paper or film. Therefore, there is no problem if the amount is slightly over the specified thickness. However, when a considerable amount exceeds the specified thickness of the printing plate, it is preferable to adjust the plate thickness only at the processing portion of the printing plate.

  The present invention can be applied to the printing of a flexible base plate in an offset rotary printing press.

It is sectional drawing which shows one embodiment which inserted the spacer in the space | interval of the holding side vise and the printing plate of this invention. It is sectional drawing which shows one embodiment which inserted the spacer in the space | interval of the holding side vise and the printing plate of this invention. It is sectional drawing which shows one embodiment which inserted the spacer in the space | interval of the holding side vise and the printing plate of this invention. It is sectional drawing which shows one embodiment which inserted the spacer in the space | interval of the holding side vise and the printing plate of this invention. It is sectional drawing which shows one embodiment which processed the shape of the printing plate holding side of this invention. It is a perspective view which shows the aspect which mounted | wore the printing cylinder with the printing plate. It is sectional drawing of the holding side vise provided in the plate cylinder. It is sectional drawing of the printing plate near the holding side vise. It is a top view which shows the printed image from which the favorable initial registration was obtained. It is sectional drawing of the holding side vise provided in the plate cylinder. It is sectional drawing of the printing plate near the holding side vise. It is a top view which shows the printing image of the initial registration which a partial distortion generate | occur | produced.

Explanation of symbols

1 Cross section of vise side vise 3 Printing plate 4 N type spacer 5 U type spacer 6 V type spacer 7 Printing plate whose shape on the holding side is processed into d type 8 Printing plate wound around plate cylinder 9 Plate cylinder 10 Overall gripping side vise 11 Overall gripping side vise 12, 16 Cross section of printing plate gripping 13 Printing paper 14 Printed image with good initial registration 15 Printing plate with deflection 17 Partial Print image of initial register in which a large amount of distortion has occurred X Space provided for inserting the printing plate in the holding side vise Y Depth provided for inserting the printing plate in the holding side vise

Claims (3)

  In a printing method in an offset rotary printing press, a spacer is inserted between the vise and the printing plate that is generated when the printing plate is inserted into a holding vise provided in the plate cylinder, and the deflection of the printing plate that occurs at the interval A printing method in a rotary offset printing press characterized in that a good initial register is obtained.   2. The printing method for an offset rotary printing press according to claim 1, wherein the spacer has a shape selected from d-type, N-type, U-type and V-type.   In the printing method on an offset rotary printing press, the printing plate holding side shape is processed into a shape selected from d-type, N-type, U-type, and V-type, thereby causing printing caused by the gap between the holding-side vise and the printing plate. A printing method in a rotary offset printing press characterized in that a good initial registration is obtained by removing the deflection of the printing plate.

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