JP2005074868A - Printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a web-fed rotary gravure press capable of applying high precise printing even to a web having undulation or an uneven web. <P>SOLUTION: A plate cylinder 11 forming a gravure cell 12 on an outer periphery is opposed to an impression cylinder 1 having a resin film layer 3 on an outer periphery. A hardness of the filmed layer 3 is made to have a hardness exceeding a Shore hardness of HS 90 to raise a facial pressure or a contact part of the impression cylinder 1 and the plate cylinder 11 in printing when a printing pressure is loaded to the impression cylinder 1 and the plate cylinder 11, a smoothness of the web W is raised by the facing pressure to carry out high precise printing. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a printing apparatus that supplies ink into cells formed on the outer periphery of a plate cylinder and continuously prints on one side of a web.

  A plate cylinder is mounted on the impression cylinder, and the ink in the cells formed on the outer periphery of the plate cylinder is transferred between the cylinders and transferred to a web that runs in one direction, and is continuously printed on one side of the web. In a printing apparatus configured to perform the above, a coating layer made of a resin such as polyurethane rubber is usually provided on the outer periphery of the impression cylinder.

  Here, when the hardness of the coating layer of the impression cylinder is low, the coating layer is greatly elastically deformed by the printing pressure applied between the impression cylinder and the plate cylinder, and the impression cylinder is heated by energy accumulated due to strain. Thus, the ink viscosity decreases due to contact with the impression cylinder, or the plate cylinder is thermally expanded, and printing with high accuracy cannot be performed.

  Therefore, in the conventional printing apparatus, the hardness of the coating layer of the impression cylinder is set to a hardness of around Shore hardness HS85.

  By the way, in a conventional printing apparatus in which the hardness of the coating layer of the impression cylinder is set to around Shore hardness HS85, printing is usually performed with an extremely high printing pressure of about 35 KN / m. In this case, the coating layer of the impression cylinder is elastically deformed by the load of the printing pressure and the nip width is increased, and conversely, the surface pressure is reduced. At the time of printing, there is a disadvantage that the smoothness of the web cannot be corrected and high-precision printing cannot be performed.

  An object of the present invention is to provide a printing apparatus capable of performing printing with high accuracy even on a web having undulations, irregularities, or a web having a rough surface.

  In order to solve the above-mentioned problems, in the first invention, a plate cylinder having cells formed on the outer periphery thereof is opposed to an impression cylinder having a resin coating layer on the outer periphery, and the plate cylinder is supplied to the cells of the plate cylinder. In a printing apparatus in which ink is transferred between an impression cylinder and a plate cylinder and transferred to a web running in one direction to continuously print on one side of the web, the coating layer has a Shore hardness exceeding HS90. Adopted a hard structure.

  Here, a thermosetting resin such as polyurethane rubber can be employed as the coating layer of the impression cylinder.

  As described above, by setting the hardness of the coating layer to a hardness exceeding the Shore hardness HS90, the elastic deformation of the coating layer during printing is small, and the impression cylinder and the plate cylinder are in contact with each other with a narrow nip width. The surface pressure can be increased, and the smoothness of the printed web can be increased by the surface pressure.

  In the second aspect of the invention, a plate cylinder having cells formed on the outer periphery thereof is provided opposite to the impression cylinder, and ink supplied to the cells of the plate cylinder is inserted between the impression cylinder and the plate cylinder in one direction. In a printing apparatus in which printing is continuously performed on one side of a web by transferring to a traveling web, the impression cylinder is formed by a roll body made of metal and a plating film layer formed on the outer periphery of the roll body. The configuration is adopted.

  Here, the plating film layer may be chromium plating or copper plating.

  As in the second aspect of the present invention, printing is performed by applying a printing pressure to the impression cylinder and the plate cylinder as in the first aspect of the invention by using a metal having a plating film layer formed on the surface of the roll body as the impression cylinder. Sometimes the surface pressure at the contact portion between the impression cylinder and the plate cylinder can be increased, and the smoothness of the printed web can be improved.

  As described above, in both the first invention and the second invention, the surface pressure of the contact portion between the impression cylinder and the plate cylinder can be increased, so that the web smoothness is increased by the surface pressure. Highly accurate printing can be performed even on webs with undulations, irregularities or rough surfaces. In addition, when the surface pressure is equal to the surface pressure of a conventional printing apparatus, the printing pressure can be lowered, and the durability of the impression cylinder, the plate cylinder, or the frame that supports each cylinder can be improved. it can.

  Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the impression cylinder 1 and the plate cylinder 11 are arranged vertically, and both the cylinders 1 and 11 are reversely rotated in the direction of the arrows in the figure and are inserted between the cylinders 1 and 11. The web W runs in the direction of the arrow (right direction) in the figure.

  As shown in FIGS. 1 and 2, the impression cylinder 1 has a configuration in which a coating layer 3 having elasticity is provided on the outer periphery of a metal roll body 2.

  The coating layer 3 is made of a thermosetting resin such as polyurethane rubber and has a hardness exceeding the Shore hardness HS90.

  As shown in FIG. 1, the plate cylinder 11 is made of metal, and a fine gravure cell 12 corresponding to a printed pattern is formed on the outer periphery thereof. Highly fluid ink is supplied to the outer periphery of the plate cylinder 11 from an inking device (not shown), and excess ink adhering to the outer periphery of the plate cylinder 11 is scraped off by a doctor blade (not shown). The ink remaining in the gravure cell 12 is transferred to the web W, and printing is continuously performed on one side of the web W.

  When printing on the web W, the impression cylinder 1 and the plate cylinder 11 are loaded with a printing pressure of about 35 KN / m. At this time, since the coating layer 3 provided on the outer periphery of the impression cylinder 1 has a hardness exceeding the Shore hardness HS90, the coating layer 3 is not greatly elastically deformed.

  For this reason, the nip width at the contact portion between the coating layer 3 of the impression cylinder 1 and the plate cylinder 11 is small, and the surface pressure is high. As described above, since the surface pressure at the contact portion between the coating layer 3 and the plate cylinder 11 can be increased by setting the hardness of the coating layer 3 to a hardness exceeding the Shore hardness HS90, When the web W having a rough surface is inserted between the impression cylinder 1 and the plate cylinder 11, the smoothness of the web W can be improved and printing with high accuracy can be performed.

  When the surface pressure between the impression cylinder 1 and the plate cylinder 11 is substantially the same as that in the case of a conventional gravure rotary printing apparatus, the printing pressure can be lowered to about 25 KN / m. The durability of the parts such as the cylinder 11 or the frame that supports the both cylinders 1 and 11 can be enhanced.

  In the embodiment shown in FIG. 1 and FIG. 2, the pressure drum 1 having a resin coating layer 3 on the outer periphery is adopted, but the pressure drum 1 shown in FIG. 3 may be adopted.

  The impression cylinder 1 shown in FIG. 3 includes a roll body 4 made of metal and a plating film layer 5 formed on the outer periphery of the roll body 4. As the plating film layer 5, chrome plating or copper plating is employed.

  When the impression cylinder 1 having the plated coating layer 5 as described above is adopted in a gravure rotary printing apparatus, the plated coating layer 5 is harder and less elastically deformed than the coated layer 3 made of a thermosetting resin. The surface pressure at the contact portion between the impression cylinder 1 and the plate cylinder 11 can be increased during printing in which printing pressure is applied to the impression cylinder 1 and the plate cylinder 11.

  Therefore, similar to the gravure rotary printing apparatus shown in FIG. 1, the smoothness of the web W that is inserted between the impression cylinder 1 and the plate cylinder 11 to be printed can be improved. High printing.

Schematic diagram of a partly cutout showing an embodiment of a gravure rotary printing apparatus according to the present invention 1 is a partially cutaway front view of the impression cylinder shown in FIG. Partially cutaway front view showing another example of an impression cylinder

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Impression cylinder 2 Roll main body 3 Coating layer 4 Roll main body 5 Plating coating layer 11 Plate cylinder 12 Gravure cell

Claims (2)

  A plate cylinder with cells formed on the outer periphery is placed on an impression cylinder having a resin coating layer on the outer periphery, and ink supplied to the cells of the plate cylinder is inserted between the impression cylinder and the plate cylinder to travel in one direction. A printing apparatus, wherein the coating layer is made to have a hardness exceeding the Shore hardness HS90 in a printing apparatus in which printing is continuously performed on one side of the web by transferring to a web.   A plate cylinder having cells formed on the outer periphery of the impression cylinder is provided, and the ink supplied to the cell of the plate cylinder is transferred between the impression cylinder and the plate cylinder and transferred to a web that runs in one direction. A printing apparatus in which printing is continuously performed on one side, wherein the impression cylinder is formed of a roll body made of metal and a plating film layer formed on an outer periphery of the roll body.

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