JP2001162761A - Printing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a printing machine by which a smooth and high density printing can be obtained without printing the same picture pattern twice as in the conventional printing and operational efficiency and workability of the printing machine can be improved. SOLUTION: In a printing machine having at least a plate cylinder, an impression cylinder and an ink feeding device for feeding an ink to the above described plate cylinder, a cylinder for pressing which rotates while pressing is performed to the above described impression cylinder is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing machine capable of improving the reproducibility of a printed pattern as compared with a conventional printing machine.

[0002]

2. Description of the Related Art Conventionally, for example, an offset printing press is provided with a plate cylinder, a blanket cylinder, an impression cylinder, and an ink supply device for supplying ink to the plate cylinder. After the ink on the plate cylinder is transferred to the blanket cylinder, which is called a blanket cylinder, the printing sheet is moved between the blanket cylinder and the impression cylinder while being sandwiched between the blanket cylinder and the impression cylinder. Ink is transferred to a sheet for printing.
The printing press for water-containing ink is provided with a dampening device for supplying water to the plate cylinder.

In these printing presses, various measures have conventionally been taken from the viewpoint of materials and methods in order to improve the reproducibility of printed pictures. For example, in terms of material, measures are being taken to develop inks having properties suitable for various resins, or to coat the surface with an anchor layer in order to improve the adhesion of the paper surface. Also, in terms of method,
The same pattern is printed twice, a unit of two colors is used, or a corona treatment is applied to improve the reproducibility of the printed pattern.

[0004] However, in the above-mentioned conventional measures, for example, a test must be performed every time a new material is developed, so that there is a problem that a great deal of time and development costs are required, efficiency is low, and economic efficiency is low. Further, measures such as printing the same pattern twice require twice as many printing steps, resulting in poor work efficiency and low registration accuracy, and require high skills.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a smooth and high-density print without printing the same pattern twice as in the prior art, and to improve the operation efficiency and workability of the printing press. An object of the present invention is to provide a printing press capable of improving the printing.

[0006]

According to the present invention, there is provided a printing press having at least a plate cylinder and an impression cylinder, and an ink supply device for supplying ink to the plate cylinder. It is characterized by comprising a pressurizing cylinder that rotates while rotating.

Further, the pressure cylinder has the same diameter as the blanket cylinder or the plate cylinder or a diameter of an integral multiple. Further, the pressurizing cylinder has the same configuration as a blanket cylinder.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a sectional view of a main part of a printing press according to the present invention, and FIG. 2 is a front view conceptually showing a printing press provided with a plurality of printing units according to the present invention.

As an embodiment of the printing press of the present invention, for example, using an offset printing press shown in FIG. 1, the printing press 1 of the present invention comprises at least a plate cylinder 2, a blanket cylinder 3, an impression cylinder 4, In addition to a general printing mechanism including an ink supply device 7 that supplies ink to the printing plate of the plate cylinder 2 by a plurality of ink supply roller groups 6 with the ink stored in the ink storage unit 5, the pressure A pressurizing drum 8 that rotates while pressurizing the drum 2 is provided.

The pressurizing cylinder 8 has the same diameter and the same specifications as the blanket cylinder 3, and is similar to the blanket cylinder 3 provided by applying pressure to the impression cylinder 4. The blanket cylinder 3 is also provided with the same pressure as that of the blanket cylinder 3. Further, the pressing cylinder 8 does not necessarily have to have the same diameter as the blanket cylinder 3 as long as it has at least an integral multiple of the diameter of the blanket cylinder 3. This is to prevent the printing image from shifting by making the position where the pressurizing cylinder 8 comes into contact with the ink image transferred to the same position always at the same position. In FIG. 1, the pressing cylinder 8 has the same diameter as the blanket cylinder 3.

The pressurizing cylinder 8 preferably has the same configuration as the blanket cylinder 3.
By using the pressurizing cylinder 8 having the same configuration as that of the blanket cylinder 3, the same printing pressure can be applied to the printing target sheet, and stable printing can be performed. For example, the blanket cylinder 3 is configured such that a rubber blanket is wound around the outer periphery of a cylinder, and the rubber blanket is wound by a winding device incorporated in the cylinder. It is preferable to use one having the same configuration as the above. Further, on both sides of the impression cylinder 4, intermediate cylinders 9a and 9b for transferring a sheet to be printed are provided similarly to a normal offset printing press.

In general, an offset printing press is provided with a plurality of printing units, each of which includes a plate cylinder, a blanket cylinder, an impression cylinder, and an ink supply device for supplying ink to the plate cylinder, for each ink of a different color. However, a pressing cylinder 8 is provided for each of the impression cylinders 4 of the printing units. FIG. 2 shows a front view conceptually showing a printing press having a plurality of printing units 10a to 10d according to the present invention.
An ink supply device (not shown) and a plate cylinder 11a
To 11d, blanket cylinders 12a to 12d, and impression cylinder 1
3a to 13d and pressurizing cylinders 14a to 14d provided so as to press against the impression cylinders 13a to 13d.

[0013] Between the impression cylinders 13a to 13d,
Intermediate cylinders 15a to 15d are provided, respectively. Further, in order to carry in the print target sheet, there is a carry-in section 16 for carrying in the print target sheet from the supply device of the print target sheet before the first print unit 10a, and after the last print unit 10d. A paper discharge shaft 17 of a paper discharge device that discharges a sheet to be printed after printing is completed, and an endless chain 18 that runs around the paper discharge shaft 17 is provided.

When printing is performed on a sheet to be printed by the above-described printing machine, the sheet to be printed carried in from the carry-in section 16 is transferred to the printing unit 10a provided first.
At a position between the blanket cylinder 3 and the impression cylinder 4.
In the printing unit 10a, the ink stored in the ink storage unit 5 is supplied to the plate cylinder 11 by a plurality of ink supply rollers.
a, and after transferring the ink of the printing plate to the blanket cylinder 12a, the sheet to be printed is moved while sandwiching the printing sheet between the blanket cylinder 12a and the impression cylinder 13a. Printing is performed by transferring the ink to the sheet to be printed.

Next, the sheet to be printed is sandwiched between the pressing cylinder 14a and the impression cylinder 13a, and is then moved to the printing unit 10b while applying pressure. After that, the next printing unit 10b also performs printing by transferring the ink of another color from the printing plate of the blanket cylinder 12b to the printing sheet by the same mechanism as the printing unit 10a, and then printing the printing sheet. Body 14b and impression cylinder 13 and b
Move it while pinching it. In this way, the sheet to be printed is sequentially conveyed from the printing unit 10a to the printing unit 10d, and then delivered to the chain gripper provided on the endless chain 18 and discharged.

Therefore, in the present invention, after the ink is transferred from the printing plate of the blanket cylinders 12a to 12d to the sheet to be printed for each printing unit, the ink is reversely transferred from the sheet to be printed, and the smoothed pattern is reproduced. Transfer. Here, the pressurizing cylinders 14a to 14
Since the pressure is applied between the impression cylinders 13a to 13d by d, a high-concentration thin-film printing surface can be formed on the sheet to be printed, and the quality can be improved. In particular, in printing on a card base material when manufacturing a magnetic card, a print layer is often formed on the upper surface of a magnetic stripe formed on the card base material to apply an entire design such as a pattern or pattern. In order to reliably write data on a magnetic stripe or read data recorded on the magnetic stripe by a card reader / writer, it is necessary to form a thin print layer, and a card substrate as a print sheet This is preferable because a thin printed surface can be formed at a high concentration.

The present invention is not limited to the above-described offset printing press, but can be used for all printing presses such as sheet-fed printing presses and rotary printing presses in which ink is transferred to paper on a cylinder. The present invention can also be applied to a machine without a blanket cylinder, such as a letterpress machine, by providing a pressurizing cylinder that rotates while pressurizing the impression cylinder.
In addition, the present invention can be used in a printing method in which the density of solid printing tends to be uneven, such as letterpress printing, and a high-quality printed pattern can be obtained in letterpress printing as well.

[0018]

As described above, according to the printing press of the present invention, smooth and high-density printing can be obtained without printing the same pattern twice as in the conventional printing press. Operation efficiency and workability can be improved, and this is particularly effective for a raw material of resin having poor ink adhesion. In addition, by making the pressure cylinder the same diameter as the blanket cylinder or a diameter of an integral multiple, a pressure cylinder suitable for each printing machine can be selected and provided. Furthermore, by making the cylinder for pressurization the same configuration as the blanket cylinder,
The same adhesiveness as the blanket cylinder can be exerted on the sheet to be printed, and a stable pressure can be applied to the printing surface of the sheet to be printed.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of a printing press according to the present invention.

FIG. 2 is a front view conceptually showing a printing press having a plurality of printing units according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printing machine 2, 11a, 11b, 11c, 11d Plate cylinder 3, 12a, 12b, 12c, 12d Blanket cylinder 4, 13a, 13b, 13c, 13d Impression cylinder 5 Ink storage part 6 Ink supply roller group 7 Ink supply device 8 , 14a, 14b, 14c, 14d Pressing cylinder 9a, 9b, 15a, 15b, 15c, 15d Intermediate cylinder 10a, 10b, 10c, 10d Printing unit 16 Loading unit 17 Discharge shaft 18 Endless chain

Claims (3)

[Claims] 1. A printing press having at least a plate cylinder, an impression cylinder, and an ink supply device for supplying ink to the plate cylinder, comprising a pressurizing cylinder that rotates while applying pressure to the impression cylinder. A printing press characterized by the following. 2. The printing press according to claim 1, wherein the pressurizing cylinder has the same diameter as the blanket cylinder or the plate cylinder or a diameter of an integral multiple. 3. The printing press according to claim 1, wherein the pressurizing cylinder has the same configuration as a blanket cylinder.