JP4617486B2 - Wiping roller for intaglio printing press - Google Patents

Description

  The present invention relates to a wiping roller to which titanium oxide is added in order to prevent troubles caused by wear of a wiping roller used in an intaglio printing press.

  As a wiping roller for an intaglio printing press, a rubber roller in which an upper layer of a metal core that is a shaft body is coated with acrylonitrile butadiene rubber (NBR) or a resin roller in which soft polyvinyl chloride (PVC) is coated is used. These rollers are excellent in moldability, oil resistance, and viscoelasticity, but are in pressure contact with the intaglio surface mounted on the intaglio cylinder, and are caused by frictional heat generated when wiping off excess ink on the intaglio surface. Surface hardness decreases and wears. This wear is affected by the shape of the image line on the printing plate and is non-uniformly generated. As a result, it becomes impossible to stably wipe off excess ink over time, which causes printing trouble.

  As an alternative material for the wiping roller for the intaglio printing machine, there is a method of using urethane as a roller material in order to improve wear. In this case, a certain amount of urethane is blended with the polyvinyl chloride resin material, and a resin layer is formed by applying and firing the roller core. However, since the roller base material is a polyvinyl chloride resin material, wear occurs as in the case of the conventional wiping roller, and the ink cannot be completely wiped on the wiping roller over time. This causes a printing failure called “wiping residue” in which the remaining ink adheres to the printed matter, and a printing failure called “solvent stain” in which the dirty cleaning liquid adheres to the printed matter.

Further, some wiping rollers in which metal oxide is added to PVC pasting resin improve ink scraping and durability, which cannot be obtained with conventional wiping rollers. However, in recent years, high-speed printing (sheets; 10,000 to 12,000 sheets / hour) has been the mainstream, roller wear has occurred remarkably, and as a durability, about 100,000 sheets can be printed on a sheet. When carried out, the surface of the wiping roller was made uneven to cause a printing failure. In order to suppress this printing failure in advance, the operator has to monitor the surface of the printed product and the wiping roller sufficiently, and the workability is poor. Further, the surface color of the wiping roller becomes golden due to baking, and the liquid rise and the solvent contamination cannot be instantaneously discriminated. As a wiping roller for an intaglio printing machine taking these problems into consideration, there is a strong demand for a roller that can easily determine the solvent appearing on the roller surface, is hardly affected by ink, and can prolong the life.

  As a wiping roller for an intaglio printing press, a wiping roller for an intaglio printing press having at least two urethane coating layers on the surface layer as disclosed in JP-A-2003-237019, the uppermost urethane layer of the urethane coating layer The wiping roller for an intaglio printing press described above is characterized in that the hardness of the JIS-A hardness is 85 ° to 97 °, and the compression modulus of the urethane coating layer is 9 to 28 MPa. There is a configuration of the wiping roller for an intaglio printing press described above.

  In addition, PVC pasting resin, plasticizer, and metal oxide, which are various materials for wiping rollers as disclosed in JP-A-2001-232752, are weighed, stirred, kneaded, defoamed, and then formed into a thin film on the base. There is a type that manufactures a wiping roller by repeating coating operation and heating reaction, and finally polishing.

Japanese Patent Laid-Open No. 2003-237019 JP 2001-232752 A

  The invention is superior in wear resistance and can extend the life as compared with conventional rubber materials such as NBR and PVC, such as NBR and PVC. However, the roller surface becomes uneven as time passes, and eventually the roller surface becomes uneven, and residual ink and dirty cleaning liquid appearing on the roller surface from the recesses adhere to the printed material, making it difficult to obtain a high-quality printed material. Come. In addition, although the wear frequency was slowed down, it was indispensable to periodically replace the roller regardless of wear.

  In addition, the wiping roller to which urethane resin or metal oxide is added requires 2-3 times the cost for manufacturing the roller as compared with the conventionally used NBR or PVC roller, but only a slight life extension is desired. I couldn't. In addition, the operator's work is not greatly reduced as compared with the prior art, and there is a case where the operation is not transferred as a wiping roller for an intaglio printing press, and there is a current situation that is not fixed.

  In order to solve the above problems, the present invention improves printing performance over a conventional wiping roller for a printing press, extends the life, and easily identifies the cleaning liquid appearing on the roller surface. To provide a roller.

  In order to solve the above-described problems, a wiping roller for an intaglio printing press according to the present invention is a roller that presses against an intaglio surface mounted on an intaglio cylinder, rotates in a direction opposite to the intaglio surface, and reciprocates in an axial direction. A wiping roller for an intaglio printing press in which at least one rubber layer or resin layer is coated on a shaft core, and the entire surface layer or a part of the wiping roller is made of rubber and / or resin containing titanium oxide. It is characterized by that.

  In addition, a part of the surface layer of the wiping roller is a region that is in contact with an image area that is a region on which the pattern of the intaglio surface that is in pressure contact with the wiping roller is applied.

The main component of the surface material of the wiping roller is a wiping roller made of ebonite, urethane, vinyl chloride, nitrile rubber rubber and / or thermoplastic resin, thermosetting resin, and is crosslinked to the surface material. The surface hardness of the area in contact with the image area is 1 to 3 ° in JIS-A from the area in contact with the non-image area that is not provided with the intaglio surface pattern. It is characterized by being lowered.

  Further, the diameter of the wiping roller in contact with the image area is 0.01% to 0.05% larger than the diameter of the wiping roller in contact with the non-image area.

  The wiping roller of the present invention is for a conventional intaglio printing press using an NBR roller or a PVC roller by arranging a rubber and / or resin to which titanium oxide having an appropriate hardness and excellent wear resistance is added in an upper layer. Unlike a wiping roller, repeated roller replacement work due to wear is not required, and printing troubles due to abrasion, peeling, swelling, etc., seen in conventional wiping rollers can be avoided even by repeated use over a long period of time.

  In addition, the wiping roller of the present invention having a rubber and / or resin added with titanium oxide in the uppermost layer is difficult to soften the roller surface, and the solvent component in the ink is difficult to permeate. In addition, there is an effect that a high-quality printed matter can be obtained.

  In addition, since the roller surface becomes white due to the added titanium oxide, it is easy to detect residual ink and dirty cleaning liquid appearing on the surface, and it is possible to suppress the occurrence of paper loss beforehand.

  Further, since the hardness of the roller surface can be stabilized, it is possible to reduce fine contact pressure adjustment for the operator to stabilize the quality and to save the labor.

Furthermore, according to the wiping roller for an intaglio printing press of the present invention, all the disadvantages caused by the conventional wiping roller for an intaglio printing press are eliminated, and it has sufficient durability for repeated use over a long period of time, and the printing quality is high. There is an effect that it does not decrease.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a schematic view according to the present invention. 2 and 3 are schematic views of another embodiment according to the present invention. FIG. 4 is a schematic view of a general wiping roller.

  As shown in FIG. 4, a general wiping roller 5 is obtained by winding NBR 4 around a metal iron core 2 until it has an effective diameter (Φ325.0 mm) suitable for printing, and subjecting it to surface polishing. In this case, the NBR 4 may be changed to PVC, or each may be used in multiple layers. Furthermore, cobalt which is a urethane resin or a metal oxide may be contained.

  The wiping roller 1 of the present invention shown in FIG. 1 is formed by winding a titanium oxide-containing resin 3 around a metal iron core 2 until it has an effective diameter suitable for printing, and performing surface polishing. Titanium oxide not only has an effect of suppressing hardness softening due to frictional heat with the intaglio surface of the wiping roller, but also has a feature that can control the penetration of the varnish contained in the ink. %), The surface of the wiping roller can be made white. A titanium oxide-containing rubber may be used instead of the titanium oxide-containing resin 3.

  The wiping roller 1 of the present invention uses the titanium oxide-containing resin 3 only in a part as shown in FIG. 2 in order to make contact with an image area that is an area on which an intaglio surface pattern is applied. In this case, the amount of heat stored in the roller due to contact with the intaglio surface is released to a portion that does not contain titanium oxide, and the life extension of the wiping roller can be promoted.

  Further, as shown in FIG. 3, in consideration of wear of the wiping roller, the diameter of the roller in contact with the image area is increased by 0.1 mm (Φ325.1 mm) in advance. In general, when the surface of the roller finished in a flat state is brought into contact with the intaglio surface and the roller surface in contact with the image area is worn during printing, printing is stopped and the entire surface of the roller is polished. To return to a flat state.

  In the roller of the present invention, the surface portion where the diameter of the roller becomes large and the image area of the intaglio surface come into contact with each other at the initial stage of use, and the portion of the roller gradually wears with use for a long time. The roller surface becomes flat during long-term use. Thereafter, printing can be performed without further polishing, so that the roller can be used for a long time.

  If this roller diameter is set excessively large, irregularities appear on the roller surface, and the cleaning liquid appears from there. If it is set too small, the life extension effect is difficult to be exhibited. Further, as a measure for controlling the wear of the roller in advance, the surface hardness JIS-A of the portion that contacts the image area may be set to 1 to 3 degrees lower.

  Next, Table 1 shows an example of a comparison result regarding the quality of the printed matter after a lapse of time due to the difference in the wiping rollers. Intaglio printing is carried out on a sheet of paper with 5 million sheets. The wiping roller is a wiping roller 1 (A roller) of the present invention and two types of general wiping rollers 4 (B roller and C roller). Using. After the printing of 300 million sheets, the surface of the general wiping roller 4 is markedly uneven, and it is difficult to perform printing by judging from the quality side. No. 1 was able to withstand printing of about 5 million sheets. In the evaluation of the quality of printed matter, the mark “◯” is good, the mark “Δ” is slightly good, and the mark “X” is unsuitable.

  As a result of performing printing with the wiping roller of the present invention based on the example, it was possible to obtain a printed material with good quality continuously over a long period of time. In addition, since the roller surface is white, it is possible to easily and instantaneously determine whether the cleaning liquid has risen, and it is possible for the operator to reduce the mental burden of reducing the occurrence of damaged paper (defective paper).

  Furthermore, it has been difficult in the past to determine the occurrence of damaged paper and printing defects from the state of the roller surface, but taking advantage of the roller surface being white, machine determination using an optical sensor such as color identification is possible. It became possible to carry out.

  Although the present invention has been described above, the present invention is not limited to the embodiments, and it goes without saying that there are various correspondences within the scope of the claims.

It is the schematic of the wiping roller which concerns on this invention. It is the schematic of the wiping roller of another form which concerns on this invention. It is the schematic of the wiping roller of another form which concerns on this invention. It is the schematic of a common wiping roller.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wiping roller of this invention 2 Iron core 3 Titanium oxide containing resin 4 PVC
5 General wiping rollers

Claims (4)

For an intaglio printing press in which at least one rubber layer or resin layer is coated on a roller shaft that is pressed against an intaglio surface mounted on an intaglio cylinder and rotates in the opposite direction to the intaglio surface and reciprocates in the axial direction. A wiping roller for an intaglio printing machine, wherein the entire or part of the surface layer of the wiping roller is made of rubber and / or resin containing titanium oxide. 2. The intaglio printing press according to claim 1, wherein a part of the surface layer of the wiping roller is an area in contact with an image area that is an area on which the pattern of the intaglio surface that is in pressure contact with the wiping roller is applied. Wiping roller. The main component of the surface layer material of the wiping roller is a wiping roller made of ebonite, urethane, vinyl chloride, nitrile rubber and / or thermoplastic resin, thermosetting resin, and the surface layer material has a crosslinking agent or A plasticizer was blended, and the surface hardness of the area in contact with the image area was lowered by 1 to 3 ° in JIS-A from the area in contact with the non-image area, which was not provided with the intaglio surface pattern. The wiping roller for an intaglio printing press according to claim 2 . The intaglio according to claim 3 , wherein a diameter of the wiping roller in contact with the image area is 0.01% to 0.05% larger than a diameter of the wiping roller in contact with the non-image area. Wiping roller for printing machine.

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