EP2987634A1

EP2987634A1 - Printing machine and uv ray-irradiation method therefor

Info

Publication number: EP2987634A1
Application number: EP13818179.7A
Authority: EP
Inventors: Syogo KAWAI
Original assignee: Yamato Grand Co Ltd
Current assignee: Yamato Grand Co Ltd
Priority date: 2013-04-15
Filing date: 2013-11-26
Publication date: 2016-02-24
Also published as: EP2987634A4; WO2014170934A1

Abstract

A printing press capable of performing irradiation with a sufficient quantity of ultraviolet securely to preventing incomplete curing of ultraviolet curable ink and an ultraviolet radiation method of the printing press are provided. The present invention is a printing press 100 including a printing section A provided with a plurality of impression cylinders 2 to which a printing section gripper 11 gripping and guiding a substrate 1 is attached, and a printer brought into adjacent contact with the impression cylinder 2 and printing ultraviolet curable ink onto the substrate 1 to make a printed object, and a paper ejecting section B provided with a chain 5 to which a paper ejecting section gripper 12 for gripping and guiding the printed object 1a is attached, wherein ultraviolet irradiators 21, 22 for irradiating the printed object 1a with ultraviolet are provided, and ultraviolet receivers 21a, 22a capable of receiving ultraviolet are attached to the grippers 11, 12 facing the ultraviolet irradiators.

Description

Technical Field

The present invention relates to a printing press and an ultraviolet irradiation method of the same, and in particular to a printing press which eliminates the need for performing test operations repeatedly, is capable of performing irradiation with a sufficient quantity of ultraviolet securely, and is capable of preventing incomplete curing of ultraviolet curable ink, and an ultraviolet irradiation method of the same.

Background Art

Sheet-fed offset printing, sheet-fed flexography, sheet-fed gravure printing, and the like, are known as printing techniques. Incidentally, the "sheet-fed" means substrates cut in the same prescribed size. That is, in a sheet-fed printing press, not a long substrate but substrates cut in the same prescribed size are printed one by one in succession.
These printing techniques generally adopt a system in which a printing press prints ultraviolet curable ink onto a substrate, such as paper, and then an ultraviolet irradiator cures the ultraviolet curable ink.
For example, an offset printing press is known that prints ink onto a printing surface of a running printing substrate via a printing plate mounted on an outer periphery of a plate cylinder and a blanket mounted on an outer periphery of a blanket cylinder, and that irradiates the ink with ultraviolet to cure the ink (for example, see Patent Literature 1).

Citation List

Patent Literature

PTL 1: Japanese Patent Application Laid-Open No. 2009-274432 .

Summary of Invention

Technical Problem

In conventional printing presses, including the offset printing press described in Patent Literature 1 mentioned above, however, the irradiation quantity of ultraviolet, generally, varies easily, and aging deterioration is also significant.
Therefore, conventionally, it is necessary to perform test operations repeatedly before an actual operation and determine the irradiation quantity of ultraviolet based on expert's experimental rules, taking into consideration a curing state of ultraviolet curable ink.
Performing test operations repeatedly, however, requires time and labor, and adjustment of the irradiation quantity of ultraviolet based on expert's experimental rules is not always reliable, and therefore the irradiation quantity of ultraviolet may be insufficient, which may cause incomplete curing of ultraviolet curable ink.
The present invention has been made in view of these circumstances, and an object thereof is to provide a printing press which eliminates the need for performing test operations repeatedly, is capable of performing irradiation with a sufficient quantity of ultraviolet securely, and is capable of preventing incomplete curing of ultraviolet curable ink, and an ultraviolet irradiation method of the same.

Solution to Problems

As a result of intensive research of the present inventor (inventors) to solve the above problem, the present inventor(s) has(have) been found that the above problem can be solved, unexpectedly, by attaching an ultraviolet receiver to a printing section gripper and/or a paper ejecting section gripper gripping and guiding a printed object, and, based on an ultraviolet quantity directly received by the ultraviolet receiver from an ultraviolet irradiator, adjusting an ultraviolet quantity emitted by the ultraviolet irradiator, and has(have) the present invention.
An aspect (1) of the present invention lies in a printing press including a printing section provided with a plurality of impression cylinders to which a gripper gripping and guiding a substrate is attached, and a printer brought into adjacent contact with the impression cylinder and printing ultraviolet curable ink onto the substrate, thereby making a printed object, and a paper ejecting section provided with a chain to which a gripper for gripping and guiding the printed object is attached, wherein an ultraviolet irradiator for irradiating the printed object with ultraviolet is provided, and a printing section ultraviolet receiver capable of receiving the ultraviolet is attached to the gripper facing the ultraviolet irradiator.
An aspect (2) of the present invention lies in the printing press according to the above aspect (1), wherein the printing section is provided with a printing section ultraviolet irradiator for irradiating the printed object guided by the impression cylinders with ultraviolet, and a printing section ultraviolet receiver capable of receiving the ultraviolet is attached to the gripper in the printing section.
An aspect (3) of the present invention lies in the printing press according to the above aspect (1), wherein the paper ejecting section is provided with a paper ejecting section ultraviolet irradiator for irradiating the printed object guided by the chain with ultraviolet, and a paper ejecting section ultraviolet receiver capable of receiving the ultraviolet is attached to the gripper in the paper ejecting section.
An aspect (4) of the present invention lies in the printing press according to the above aspect (1), wherein the printing section is provided with a printing section ultraviolet irradiator for irradiating the printed object guided by the impression cylinders with ultraviolet, a printing section ultraviolet receiver capable of receiving the ultraviolet is attached to the gripper in the printing section, the paper ejecting section is provided with a paper ejecting section ultraviolet irradiator for irradiating the printed object guided by the chain with ultraviolet, and a paper ejecting section ultraviolet receiver capable of receiving the ultraviolet is attached to the gripper in the paper ejecting section.
An aspect (5) of the present invention lies in the printing press according to the above aspect (2) or (4), wherein the printing section ultraviolet receiver is attachable and detachable to the printing section gripper.
An aspect (6) of the present invention lies in the printing press according to the above aspect (3) or (4), wherein the paper ejecting section ultraviolet receiver is attachable and detachable to the paper ejecting section gripper.
An aspect (7) of the present invention lies in the printing press according to the above aspect (2) or (4), wherein a groove capable of housing the printing section gripper and the printing section ultraviolet receiver is formed in the impression cylinder.
An aspect (8) of the present invention lies in the printing press according to the above aspect (2) or (4), wherein the printing press is a sheet-fed gravure printing press or a sheet-fed flexographic press.
An aspect (9) of the present invention lies in the printing press according to the above aspect (3) or (4), wherein the printing press is a sheet-fed offset printing press.
An aspect (10) of the present invention lies in an ultraviolet irradiation method of a printing press using the printing press according to the above aspect (2) or (4), wherein, based on an ultraviolet quantity received by the printing section ultraviolet receiver from the printing section ultraviolet irradiator, an ultraviolet quantity to be emitted by the printing section ultraviolet irradiator is adjusted during operation.
An aspect (11) of the present invention lies in an ultraviolet irradiation method of a printing press using the printing press according to the above aspect (3) or (4), wherein, based on an ultraviolet quantity received by the paper ejecting section ultraviolet receiver from the paper ejecting section ultraviolet irradiator, an ultraviolet quantity to be emitted by the paper ejecting section ultraviolet irradiator is adjusted during operation.
An aspect (12) of the present invention lies in an ultraviolet irradiation method according to the above aspect (10) or (11), wherein information on the ultraviolet quantity is transmitted to a CPU, and the ultraviolet quantity is adjusted based on the information.

Advantageous Effects of Invention

In the printing press of the present invention, since the printing section ultraviolet receiver is attached to the printing section gripper gripping and guiding a printed object, the printing section ultraviolet receiver of the printing section can receive an ultraviolet quantity equivalent to the ultraviolet quantity directly received by the printed object from the printing section ultraviolet irradiator, so that, by adjusting the ultraviolet quantity to be emitted by the printing section ultraviolet irradiator based on the ultraviolet quantity received by the printing section ultraviolet receiver from the printing section ultraviolet irradiator, the printed object can be securely irradiated with a sufficient quantity of ultraviolet in an actual operation without the need to repeat test operations. Thereby, incomplete curing of the ultraviolet curable ink of the printed object can be securely prevented.
In the printing press of the present invention, since the paper ejecting section ultraviolet receiver is attached to the paper ejecting section gripper gripping and guiding a printed object, the paper ejecting section ultraviolet receiver of the paper ejecting section can receive an ultraviolet quantity equivalent to the ultraviolet quantity directly received by the printed object from the paper ejecting section ultraviolet irradiator, so that, by adjusting an ultraviolet quantity to be emitted by the paper ejecting section ultraviolet irradiator based on the ultraviolet quantity received by the paper ejecting section ultraviolet receiver from the paper ejecting section ultraviolet irradiator, the printed object can be securely irradiated with a sufficient quantity of ultraviolet in an actual operation without the need to repeat test operations. Thereby, incomplete curing of the ultraviolet curable ink of the printed object can be securely prevented
In the printing press of the present invention, since the printing section ultraviolet receiver is attached to the printing section gripper gripping and guiding a printed object, and the paper ejecting section ultraviolet receiver is attached to the paper ejecting section gripper gripping and guiding a printed object, the printing section ultraviolet receiver of the printing section can receive an ultraviolet quantity equivalent to the ultraviolet quantity directly received by the printed object from the printing section ultraviolet irradiator, and the paper ejecting section ultraviolet receiver of the paper ejecting section can receive an ultraviolet quantity equivalent to the ultraviolet quantity directly received by the printed object from the paper ejecting section ultraviolet irradiator.
Therefore, by adjusting the ultraviolet quantity to be emitted by the paper ejecting section ultraviolet irradiator based on the ultraviolet quantity received by the paper ejecting section ultraviolet receiver from the paper ejecting section ultraviolet irradiator, and by adjusting the ultraviolet quantity to be emitted by the paper ejecting section ultraviolet irradiator based on the ultraviolet quantity received by the paper ejecting section ultraviolet receiver from the paper ejecting section ultraviolet irradiator, the printed object can be securely irradiated with a sufficient quantity of ultraviolet in an actual operation without the need to repeat test operations.
In this case, since the ultraviolet curable ink can be temporarily cured in the printing section, the respective irradiation quantities of ultraviolet to the printed object in the printing section ultraviolet irradiator and the paper ejecting section ultraviolet irradiator can be reduced. As a result, the burdens on the ultraviolet irradiators are lightened, so that aging deterioration of ultraviolet lamps can be suppressed. In addition, since the ultraviolet curable ink is temporarily cured, contamination due to ink transfer from a substrate to an offset printing press in the course of manufacture can also be prevented.
In the printing press of the present invention, when the printing section ultraviolet receiver is attachable and detachable to the printing section gripper, or when the paper ejecting section ultraviolet receiver is attachable and detachable to the paper ejecting section griper, replacement of the ultraviolet receiver is facilitated, and the ultraviolet receiver can be attached to a desired position according to necessity.
In the printing press of the present invention, since a groove capable of housing the printing section gripper and the printing section ultraviolet receiver is formed in an impression cylinder, the printing section gripper and the printing section ultraviolet receiver are not obstacles to conveyance of the substrate.
In the ultraviolet irradiation method of the present invention, since the printing press according to the above aspect (1) or (3) is used, and the ultraviolet quantity to be emitted by the printing section ultraviolet irradiator is adjusted based on the ultraviolet quantity received by the printing section ultraviolet receiver from the printing section ultraviolet irradiator, the ultraviolet curable ink can be securely irradiated with a sufficient quantity of ultraviolet, so that incomplete curing of the ultraviolet curable ink can be prevented.
In addition, since the printing press according to the above aspect (2) or (3) is used, and the ultraviolet quantity to be emitted by the paper ejecting section ultraviolet irradiator is adjusted based on the ultraviolet quantity received by the paper ejecting section ultraviolet receiver from the paper ejecting section ultraviolet irradiator, the ultraviolet curable ink can be securely irradiated with a sufficient quantity of ultraviolet, so that incomplete curing of the ultraviolet curable ink can be prevented.
In the ultraviolet irradiation method of the present invention, since information on the ultraviolet quantity is transmitted to the CPU, and adjustment of the ultraviolet quantity is performed based on the information, adjustment of the ultraviolet quantity can be rapidly performed.
In addition, since chronological information on the ultraviolet quantity can be stored in the CPU, it is also possible to analyze the information, thereby predicting the degree of deterioration of the ultraviolet irradiators, a method of adjusting an ultraviolet quantity, or the like.

Brief Description of Drawings

Figure 1 is a schematic side view showing a printing press according to a first embodiment;

Figure 2 is a schematic perspective view showing an impression cylinder of a printing section in the printing press according to the first embodiment;
Figure 3 is a schematic perspective view showing part of a chain of a paper ejecting section in the printing press according to the first embodiment;
Figure 4 is a schematic side view showing that a paper ejecting gripper has gripped a printed object in the printing press according to the first embodiment;
Figure 5 is a schematic side view showing a printing press according to a second embodiment; and
Figure 6 is a schematic side view showing a printing press according to a third embodiment.

Description of Embodiments

With reference to the drawings, if necessary, preferred embodiments of the present invention will be described below in detail. Incidentally, in the drawings, identical elements are denoted by identical reference signs, so that a duplicated description is omitted. In addition, a positional relationship, such as top and bottom or right and left, is based on a positional relationship shown in the drawings, unless otherwise noted. Further, the ratio of dimensions of the offset printing press is not limited to the ratio of dimensions shown in the drawings.

First Embodiment

An example of a sheet-fed offset printing press will be shown as a first embodiment of a printing press according to the present invention.
Figure. 1 is a schematic side view showing a printing press according to a first embodiment.
As shown in Figure. 1, a printing press 100 includes a printing section A where a substrate 1 is printed, and a paper ejecting section B where a printed object 1a is collected. Incidentally, a paper feeding section from which the substrate 1 is fed to the printing section A is omitted.
The printing section A is provided with a plurality of impression cylinders 2 each provided with a gripper 11 (referred to as "printing section gripper" below) gripping and guiding the substrate 1, a printer including a blanket cylinder 3 brought into adjacent contact with each impression cylinder 2 and printing the substrate 1 with ultraviolet curable ink to make the printed object 1a and a plate cylinder 3a transferring the ultraviolet curable ink to the blanket cylinder 3, an ultraviolet receiver (referred to as "printing section ultraviolet receiver" below), not shown, attached to the printing section gripper 11, and an ultraviolet irradiator 22 (referred to as "printing section ultraviolet irradiator" below) irradiating the substrate 1 guided by the impression cylinders 2 with ultraviolet.
In the printing section A, ultraviolet curable ink applied to the so-called plate cylinder 3a is transferred to the blanket cylinder 3 made of rubber, and the ultraviolet curable ink is printed from the blanket cylinder 3 onto the substrate 1 conveyed by the impression cylinders 2 described later. It should be noted that since the printing section A is provided with a plurality of plate cylinders 3a, blanket cylinders 3, and impression cylinders 2, a plurality of designs different from each other can be printed on the substrate 1 in a superimposed manner.
Figure 2 is a schematic perspective view showing the impression cylinder of the printing section in the printing press according to the first embodiment.
As shown in Figure 2, in the printing press 100, the impression cylinder 2 is cylindrical and rotatable about the center axis thereof.
In addition, a groove 4 is formed in the surface of the impression cylinder 2 along an axial direction of the impression cylinder 2, and a similar groove 4 is also formed on the opposite side (on the rear side in Figure 2) of the surface of the impression cylinder 2. That is, the grooves 4 are formed in the surface of the impression cylinder 2 at symmetrically positions.
In the printing press 100, a printing section gripper 11 is housed and fixed in each of the grooves 4.
In this regard, the printing section gripper 11 can grip one end of the substrate 1. Incidentally, the other end of the substrate 1 is not gripped.
Therefore, while the printing section gripper 11 is gripping the substrate 1, the impression cylinder 2 rotates, thereby conveying the substrate 1 along a circumferential surface of the impression cylinder 2.
In the printing press 100, a printing section ultraviolet receiver 22a is attached to an approximately-central position of the printing section gripper 11. That is, the printing section gripper 11 and the printing section ultraviolet receiver 22a are housed in the groove 4 of the impression cylinder 2. Thus, since the printing section gripper 11 and the printing section ultraviolet receiver 22a are housed in the groove 4, the printing section gripper 11 and the printing section ultraviolet receiver 22a do not obstruct conveyance of the substrate 1.
The printing section ultraviolet receiver 22a has a small box-like shape with a light receiving portion L formed on the upper face. Incidentally, the printing section ultraviolet receiver 22a can wirelessly transmit information on the ultraviolet quantity received at the light receiving portion L, and the information is received by a receiving part of an external CPU so that the ultraviolet quantity can be displayed on a display unit of the CPU.
It should be noted that since the CPU is used, the information on the ultraviolet quantity can be stored, and it is also possible to predict the degree of deterioration of the printing section ultraviolet irradiator 22 or the method of adjusting an ultraviolet quantity, and the like, by analyzing the information on voltage and current in the printing section ultraviolet irradiator 22, the lamp temperature of the printing section ultraviolet irradiator 22, the speed of the substrate 1, and the like, together with the information on the ultraviolet quantity.
The printing section ultraviolet receiver 22a is attachable and detachable to the printing section gripper 11. Therefore, it is easy to replace the printing section ultraviolet receiver 22a, and it is possible to attach the printing section ultraviolet receiver 22a to a desired position, if necessary.
Again, with reference to Figure 1, in the printing press 100, the plurality of impression cylinders 2 are brought into adjacent contact with each other (are brought into pressure contact with each other), and each groove 4 is so formed that the grooves 4 face each other when the adjacent impression cylinders 2 rotate. Thus, the substrate 1 gripped by the printing section gripper 11 housed in the groove 4 of the impression cylinder 2 is smoothly conveyed according to the rotation of the impression cylinder 2, and, when the substrate 1 comes to the position of the groove 4 of the adjacent impression cylinder 2, the substrate 1 is passed to the printing section gripper 11 housed in the groove 4 of the adjacent impression cylinder 2, and conveyed according to the rotation of the adjacent impression cylinder 2.
That is, in the printing section A, the substrate 1 is printed with ultraviolet curable ink by each impression cylinder 2, and is also sequentially passed according to the rotation of each impression cylinder 2 and by the printing section gripper 11 disposed in each impression cylinder 2. Incidentally, this pass principle is the same as the pass principle of a convention printing press.
In the printing section A, the printing section ultraviolet irradiator 22 is provided via a mounting frame, not shown, so as to extend in the axial direction of the impression cylinder 2 at a position from which the printing section ultraviolet irradiator 22 can irradiate the substrate 1 guided by the impression cylinder 2 with ultraviolet. For example, the printing section ultraviolet irradiator 22 can be so disposed in internal space of the printing press 100 as to face the impression cylinder 2.
On the other hand, the paper ejecting section B is provided with a chain 5 provided with a gripper 12 (referred to as "paper ejecting section gripper" below) gripping and guiding the printed object 1a, an ultraviolet receiver (referred to as "paper ejecting section ultraviolet receiver" below), not shown, attached to the paper ejecting section gripper 12, ultraviolet irradiators 21 (referred to as "paper ejecting section ultraviolet irradiators" below) for irradiating the printed object 1a guided by the chain 5 with ultraviolet, and a collecting portion 7 collecting the printed object 1a.
In the paper ejecting section B, the printed object 1a printed with ultraviolet curable ink is conveyed by the chain 5, and, in the course of conveyance, the ultraviolet curable ink printed is reliably cured by the paper ejecting section ultraviolet irradiators 21 in the course of the conveyance, and thereafter the product is collected.
Figure 3 is a schematic perspective view showing part of the chain in the paper ejecting section in the printing press according to the first embodiment. The printed object 1a is not shown in Figure 3.
As shown in Figure 3, in the printing press 100, a pair of chains 5 are so disposed as to move along frames 6 disposed on both sides.
In addition, the paper ejecting section gripper 12 is laid between the pair of chains 5. Therefore, the paper ejecting section gripper 12 moves integrally with the chains 5.
The chains 5 move with the printed object 1a griped by the paper ejecting section gripper 12 so that the printed object 1a is conveyed according to the movement of the chains 5.
It should be noted that the structure of the paper ejecting section gripper 12 is the same as the structure of the printing section gripper 11, and similarly the structure of the paper ejecting section ultraviolet receiver 21a is the same as the structure of the printing section ultraviolet receiver 22a. Similarly, the paper ejecting section ultraviolet receiver 21a can also wirelessly transmit information on the ultraviolet quantity received at a light receiving portion L, and the information is received by an external CPU so that the ultraviolet quantity can be displayed on a display unit of the CPU.
In addition, since the CPU is used, the information on the ultraviolet quantity can be stored, and it is also possible to predict the degree of deterioration of the paper ejecting section ultraviolet irradiator 21 or the method of adjusting the ultraviolet quantity, and the like, by analyzing the information on voltage and current in the paper ejecting section ultraviolet irradiator 21, the lamp temperature of the paper ejecting section ultraviolet irradiator 21, the speed of the substrate 1, and the like, together with the information on the ultraviolet quantity.
Like the printing section ultraviolet receiver 22a, the paper ejecting section ultraviolet receiver 21a is attachable and detachable to the paper ejecting section gripper 12. Therefore, it is easy to replace the paper ejecting section ultraviolet receiver 21a, and it is possible to attach the paper ejecting section ultraviolet receiver 21a to a desired position, if necessary.
Figure 4 is a schematic side view showing a state that the paper ejecting section gripper has gripped the printed object in the printing press according to the first embodiment.
As shown in Figure 4, in the printing press 100, the paper ejecting section gripper 12 can grip one end of the printed object 1a.
The paper ejecting section ultraviolet receiver 21a is attached to an approximately central position of the paper ejecting section gripper 12.
In the paper ejecting section B, when the printed object 1a is conveyed by the paper ejecting section gripper 12, air is blown to the lower face of the printed object 1a. That is, an air blower (not shown) is disposed below the printed object 1a, and the air blower blows air to the printed object 1a so that the printed object 1a is conveyed approximately in parallel with the chains 5 without bending downward.
Again, with reference to Figure 1, a plurality of paper ejecting grippers 12 are disposed at equal intervals corresponding to half the length of circumference of the impression cylinder 2 in a longitudinal direction of the chains 5. That is, the paper ejecting section grippers 12 are so disposed as to come to a position corresponding to the printing section gripper 11 attached to the impression cylinder 2 (the leftmost impression cylinder 2 in Figure 1) when the impression cylinder 2 rotates.
Thus, when the printed object 1a gripped by the printing section gripper 11 housed in the groove 4 of the impression cylinder 2 reaches the position of the chains 5, the printed object 1a is passed to the paper ejecting section gripper 12 attached to the chains 5 and is conveyed by the chains 5. Incidentally, the printing section gripper 11 and the paper ejecting section gripper 12 are disposed at positions corresponding to each other such that pass of the printed object 1a can be smoothly performed therebetween.
In the paper ejecting section B, the paper ejecting section ultraviolet irradiator 21 is disposed in a position from which the paper ejecting section ultraviolet irradiator 21 can irradiate the printed object 1a guided by the chains 5 with ultraviolet.
In this regard, the paper ejecting section ultraviolet irradiator 21 can be disposed in internal space of the printing press 100, for example, between the pair of chains 5.
In the printing press 100 according to the present invention, the material of the printed object 1a is not particularly limited, and an object to be printed, such as a non-water-absorbing synthetic paper, fabric, plastic film, or plastic sheet, is used according to situations.
In addition, in the printing press 10, ultraviolet curable ink is used.
Since the ultraviolet curable ink is used, post-process can be started immediately after UV irradiation, and consequently the delivery time can be shortened.
The UV curable ink includes a UV curable resin, a polymerization initiator, and a pigment. Incidentally, an additive may be included, such as a solvent, a sensitizer, a polymerization inhibitor, an antifoamer, or a surfactant.
The UV curable resin can be an acrylate, methacrylate, or unsaturated polyester resin having a polymerizable ethylenic double bond, or the like. More specifically, the UV curable resin can be polyester acrylate, epoxyacrylate, urethane acrylate, or the like.
The polymerization initiator can be benzopenone, benzoin, acetophenone, or thioxanthone polymerization initiator, or the like.
It is preferred that the temperature of the ultraviolet curable ink in use be 20 °C to 50 °C.
In addition, it is preferred that the viscosity of the ultraviolet curable ink in use be 5 Pa ·s to 1500 Pa ·s.
When the physical properties of the ultraviolet curable ink is within the above ranges, the burden on the paper ejecting section ultraviolet irradiator 21 and the printing section ultraviolet irradiator 22 can be relatively reduced.
Next, an ultraviolet irradiation method using the printing press 100 according to the first embodiment will be described.
First, in the printing section A, the substrate 1 (cut in a certain length) fed from a paper feeding section is gripped by one printing section gripper 11 of the first (upstream) impression cylinder 2, and conveyed along the circumferential surface of the impression cylinder 2 according to rotation of the impression cylinder 2.
At this time, since the impression cylinder 2 is brought into adjacent contact with the blanket cylinder 3, ultraviolet curable ink transferred from the plate cylinder 3a is printed onto the substrate 1 via the blanket cylinder 3.
Then, the substrate 1 is gripped by the printing section gripper 11 provided in the next impression cylinder 2, and is moved to the next impression cylinder 2. This operation is repeated.
In the printing section A, since the printing section ultraviolet irradiator 22 is disposed between the impression cylinders 2 inside the printing press 100 at a position from which the printing section ultraviolet irradiator 22 can irradiate the substrate 1 with ultraviolet, the substrate 1 printed is irradiated with ultraviolet by the printing section ultraviolet irradiator 22 in the course of conveyance.
At this time, since the printing section ultraviolet receiver 22a is attached to the predetermined printing section gripper 11, the printing section ultraviolet receiver 22a can receive at the light receiving portion L an ultraviolet quantity equivalent to the ultraviolet quantity directly received from the printing section ultraviolet irradiator 22, when the substrate 1 passes just below the printing section ultraviolet irradiator 22.
As described above, the information on the ultraviolet quantity received by the printing section ultraviolet receiver 22a from the printing section ultraviolet irradiator 22 is transmitted to the CPU and displayed on a display unit of the CPU. Thereby, the ultraviolet quantity to be emitted by the printing section ultraviolet irradiator 22 can be adjusted based on the information on the ultraviolet quantity.
For example, the ultraviolet quantity is measured beforehand by the printing section ultraviolet receiver 22a in a test operation so that a next actual operation can be performed with the ultraviolet quantity adjusted based on the information on the ultraviolet quantity. Thereby, irradiation of the ultraviolet quantity required at a position through which the substrate 1 actually passes can be securely performed.
In the printing press 100 according to the first embodiment, since the ultraviolet curable ink can be temporarily cured in the stage of the printing section A, the irradiation quantity of ultraviolet from the ultraviolet irradiator to the printed object in the paper ejecting section B described later can be reduced. As a result, the burden on the ultraviolet irradiator in the paper ejecting section B is reduced, so that deterioration of an ultraviolet lamp can be suppressed.
In addition, since the ultraviolet curable ink is temporarily cured, contamination due to transfer of ink from the substrate 1 to the printing press 100 in the course of manufacture can be prevented.
Next, in the paper ejecting section B, when the printed object 1a is passed from the printing section gripper 11 of the last (downstream) impression cylinder 2 to the paper ejecting section gripper 12 attached to the chains 5, it is gripped by the paper ejecting section gripper 12 and conveyed according to movement of the chains 5.
In the paper ejecting section B, since the paper ejecting section ultraviolet irradiator 21 is disposed between the pair of chains 5 at a position from which the printed object 1a can be irradiated with ultraviolet, the printed object 1a is irradiated with ultraviolet by the paper ejecting section ultraviolet irradiator 21 in the course of conveyance.
In this regard, since the paper ejecting section ultraviolet receiver 21a is attached to the predetermined paper ejecting section gripper 12, the paper ejecting section ultraviolet receiver 21a can receive at the light receiving portion L an ultraviolet quantity equivalent to the ultraviolet quantity directly received by the printed object 1a from the paper ejecting section ultraviolet irradiator 21, when the printed object 1a passes just below the paper ejecting section ultraviolet irradiator 21.
Information on the ultraviolet quantity received by the paper ejecting section ultraviolet receiver 21a from the paper ejecting section ultraviolet irradiator 21 is transmitted to the CPU, as in the case of the printing section ultraviolet receiver 22a described above, and displayed on the display unit of the CPU. Thereby based on the information on the ultraviolet quantity, the ultraviolet quantity to be emitted by the paper ejecting ultraviolet irradiator 21 can be adjusted.
For example, as in the case of the printing section A described above, it is possible to measure the ultraviolet quantity by the paper ejecting section ultraviolet receiver 21a in a test operation, adjust the ultraviolet quantity based on the information, and perform a next operation. Thereby, the printed object 1a can be securely irradiated with the ultraviolet quantity required at a position through which the printed object 1a actually passes.
Then, the printed object 1a with the ultraviolet curable ink securely cured by ultraviolet irradiation performed by the paper ejecting section ultraviolet irradiator 21 is conveyed by the chains 5, and, in the collecting portion 7, the paper ejecting section gripper 12 releases the printed object 1a, thereby collecting the printed object 1a (product) at a predetermined position.
According to the ultraviolet irradiation method using the printing press 100, the ultraviolet quantity to be emitted by the printing section ultraviolet irradiator 22 can be adjusted based on the ultraviolet quantity received by the printing section ultraviolet receiver 22a from the printing section ultraviolet irradiator 22, and the ultraviolet quantity to be emitted by the paper ejecting section ultraviolet irradiator 21 can be adjusted based on the ultraviolet quantity received by the paper ejecting section ultraviolet receiver 21a from the paper ejecting section ultraviolet irradiator 21.
In view of the above advantages, according to the ultraviolet irradiation method using the printing press 100, it is unnecessary to repeat test operations, a sufficient quantity of ultraviolet can be securely emitted, and incomplete curing of the ultraviolet curable ink can be prevented.

Second Embodiment

An example of a sheet-fed flexographic press will be shown as a second embodiment of the printing press according to the present invention.
Figure 5 is a schematic side view showing the printing press according to the second embodiment.
As shown in Figure 5, a printing press 101 includes a printing section A where a substrate 1 is printed and a paper ejecting section B where a printed object 1a after printing is collected. A paper feeding section from which the substrate 1 is fed to the printing section A is omitted.
The printing section A is provided with a plurality of impression cylinders 2 each provided with a printing section gripper 11 gripping and guiding the substrate 1, a printer including a plate cylinder 3b brought into adjacent contact with each impression cylinder 2 and printing the substrate 1 with ultraviolet curable ink to make a printed object 1a, an anilox roller 31 applying ultraviolet curable ink to the plate cylinder 3b, an ink chamber 33 applying the ultraviolet curable ink to the anilox roller 31, and a doctor blade 32 abutting on the anilox roller 31 to remove ultraviolet curable ink applied excessively to the anilox roller 31, a printing section ultraviolet receiver (not shown) attached to the printing section gripper 11, and a printing section ultraviolet irradiator 22 for irradiating the substrate 1 guided by the impression cylinders 2 with ultraviolet. That is, the printing press 101 (sheet-fed flexographic press) according to the second embodiment has a different printer from the printer of the printing press 100 (sheet-fed offset printing press) according to the first embodiment.
In the printing section A, ultraviolet curable ink is applied from the ink chamber 33 to the anilox roller 31. At this time, ultraviolet curable ink excessively applied is removed by the doctor blade 32.
Then, the ultraviolet curable ink applied to the anilox roller 31 is transferred to the plate cylinder 3b, and printed from the plate cylinder 3b onto the substrate 1 conveyed by the impression cylinder 2. It should be noted that since the printing section A is provided with a plurality of ink chambers 33, anilox rollers 31, doctor blades 32, plate cylinders 3b, and impression cylinders 2, a plurality of designs different from each other can be printed on the substrate 1 in a superimposed manner.
In the printing section A, a plurality of printing section ultraviolet irradiators 22 are provided via mounting frames, not shown, so as to extend in the axial direction of the impression cylinders 2 at positions from which the printing section ultraviolet irradiators 22 can irradiate the substrate 1 guided by the impression cylinders 2 with ultraviolet. For example, the printing section ultraviolet irradiator 22 can be so disposed in internal space of the printing press 101 as to face the impression cylinder 2.
It should be noted that in flexography, generally, because of the high viscosity of ultraviolet curable ink, ultraviolet curable ink is cured by performing ultraviolet irradiation in the printing section A, but ultraviolet irradiation is not performed in the paper ejecting section B in many cases.
Therefore, in the printing press 101, the printing section A is provided with a plurality of printing section ultraviolet irradiators 22, but the paper ejecting section B is not provided with a paper ejecting section ultraviolet irradiator.
Next, an ultraviolet irradiation method using the printing press 101 according to the second embodiment will be described.
First, in the printing section A, the substrate 1 fed from a paper feeding section is gripped by one printing section gripper 11 of the first (upstream) impression cylinder 2, and conveyed along the peripheral surface of the impression cylinder 2 according to rotation of the impression cylinder 2.
At this time, since the impression cylinder 2 is bought into adjacent contact with the plate cylinder 3b, ultraviolet curable ink transferred from the anilox roller 31 is printed onto the substrate 1 via the plate cylinder 3b.
Then, the substrate 1 is gripped by the printing section gripper 11 disposed in the next impression cylinder 2, and is moved to the next impression cylinder 2. This operation is repeated.
In the printing section A, since the printing section ultraviolet irradiator 22 is provided for each of the impression cylinders 2 inside the printing press 101 at a position from which the printing section ultraviolet irradiator 22 can irradiate the substrate 1 with ultraviolet, the substrate 1 printed is irradiated with ultraviolet by each of the printing section ultraviolet irradiators 22 in the course of conveyance.
At this time, since the printing section ultraviolet receiver 22a is attached to the predetermined printing section griper 11, the printing section ultraviolet receiver 22a can receive at the light receiving portion L an ultraviolet quantity equivalent to the ultraviolet quantity directly received by the substrate 1 from the printing section ultraviolet irradiator 22. It should be noted that the printing section ultraviolet receiver 22a may be attached to one printing section gripper 11, or may be attached to all of the printing section grippers 11.
The information on the ultraviolet quantity received by the printing section ultraviolet receiver 22a from the printing section ultraviolet irradiator 22 is transmitted to the CPU, and displayed on the display unit of the CPU.
In this regard, chronological information on the ultraviolet quantity can be stored in the CPU, so that it is also possible to analyze the information, thereby predicting the degree of deterioration of the ultraviolet irradiator, a method of adjusting the ultraviolet quantity, or the like.
In addition, it is possible to adjust the ultraviolet quantity to be emitted by the printing section ultraviolet irradiator 22 based on the information.
Next, in the paper ejecting section B, when the printed object 1a is passed from the printing section gripper 11 of the last (downstream) impression cylinder 2 to the paper ejecting section gripper 12 attached to the chains 5, it is gripped by the paper ejecting section gripper 12 and conveyed according to movement of the chains 5.
Then, in the collecting portion 7, the paper ejecting section gripper 12 releases the printed object 1a, thereby collecting the printed object 1a (product) at a predetermined position.
According to the ultraviolet irradiation method using the printing press 101, since the ultraviolet quantity to be emitted by the printing section ultraviolet irradiator 22 is adjusted based on the ultraviolet quantity received by the printing section ultraviolet receiver 22a from the printing section ultraviolet irradiator 22, a sufficient quantity of ultraviolet can be securely emitted, so that incomplete curing of the ultraviolet curable ink can be prevented.

Third Embodiment

An example of a sheet-fed gravure printing press will be shown as a third embodiment of the printing press according to the present invention.
Fig. 6 is a schematic side view showing the printing press according to the third embodiment.
As shown in Figure 6, a printing press 102 includes a printing section A where a substrate 1 is printed, and a paper ejecting section B where a printed object 1a after printing is collected. A paper feeding section from which the substrate 1 is fed to the printing section A is omitted.
The printing section A is provided with a plurality of impression cylinders 2 each provided with a printing section gripper 11 gripping and guiding the substrate 1, a printer including a plate cylinder 3c brought into adjacent contact with each impression cylinder 2 and printing the substrate 1 with ultraviolet curable ink to make a printed object 1a, an ink chamber 33 applying the ultraviolet curable ink to the plate cylinder 3c via a finisher roll 35, and a doctor blade 32 abutting on the ink chamber 33 to remove ultraviolet curable ink applied excessively, a printing section ultraviolet receiver (not shown) attached to the printing section gripper 11, and a printing section ultraviolet irradiator 22 for irradiating the substrate 1 guided by the impression cylinders 2 with ultraviolet. That is, the printing press 102 (sheet-fed gravure printing press) according to the third embodiment has a different printer from the printers of the printing press 100 (sheet-fed offset printing press)according to the first embodiment and the printing press 101 (sheet-fed flexographic press) according to the second embodiment.
In the printing section A, ultraviolet curable ink is applied to the plate cylinder 3c from the ink chamber 33 via the finisher roll 35. At this time, ultraviolet curable ink excessively applied is removed by the doctor blade 32.
Then, from the plate cylinder 3c, the ultraviolet curable ink is printed onto the substrate 1 conveyed by the impression cylinder 2. It should be noted that since the printing section A is provided with a plurality of ink chambers 33, doctor blades 32, plate cylinders 3c, and impression cylinders 2, a plurality of designs different from each other can be printed on the substrate 1 in a superimposed manner.
In the printing section A, a plurality of printing section ultraviolet irradiators 22 are provided via mounting frames, not shown, so as to extend in the axial direction of the impression cylinders 2 at positions from which the printing section ultraviolet irradiators 22 can irradiate the substrate 1 guided by the impression cylinders 2 with ultraviolet. For example, the printing section ultraviolet irradiator 22 can be so disposed in internal space of the printing press 102 as to face the impression cylinder 2.
It should be noted that in gravure printing, generally, because of the high viscosity of ultraviolet curable ink, ultraviolet curable ink is cured by performing ultraviolet irradiation in the printing section A, but ultraviolet irradiation is not performed in the paper ejecting section B in many cases.
Therefore, in the printing press 102, the printing section A is provided with a plurality of printing section ultraviolet irradiators 22, but the paper ejecting section B is not provided with a paper ejecting section ultraviolet irradiator.
Next, an ultraviolet irradiation method using the printing press 102 according to the third embodiment will be described.
First, in the printing section A, the substrate 1 fed from a paper feeding section is gripped by one printing section gripper 11 of the first (upstream) impression cylinder 2, and conveyed along the circumferential surface of the impression cylinder 2 according to rotation of the impression cylinder 2.
At this time, since the impression cylinder 2 is brought into adjacent contact with the plate cylinder 3c, ultraviolet curable ink is printed onto the substrate 1 via the plate cylinder 3c.
Then, the substrate 1 is gripped by the printing section gripper 11 disposed in the next impression cylinder 2, and is moved to the next impression cylinder 2. This operation is repeated.
In the printing section A, since the printing section ultraviolet irradiator 22 is provided for each of the impression cylinders 2 inside the printing press 102 at a position from which the printing section ultraviolet irradiator 22 can irradiate the substrate 1 with ultraviolet, the substrate 1 printed is irradiated with ultraviolet by each of the printing section ultraviolet irradiators 22 in the course of conveyance.
At this time, since the printing section ultraviolet receiver 22a is attached to the predetermined printing section griper 11, the printing section ultraviolet receiver 22a can receive at the light receiving portion L an ultraviolet quantity equivalent to the ultraviolet quantity directly received by the substrate 1 from the printing section ultraviolet irradiator 22. It should be noted that the printing section ultraviolet receiver 22a may be attached to one printing section gripper 11, or may be attached to all of the printing section grippers 11.
The information on the ultraviolet quantity received by the printing section ultraviolet receiver 22a from the printing section ultraviolet irradiator 22 is transmitted to the CPU, and displayed on the display unit of the CPU.
In this regard, chronological information on the ultraviolet quantity can be stored in the CPU, so that it is also possible to analyze the information, thereby predicting the degree of deterioration of the ultraviolet irradiator, a method of adjusting the ultraviolet quantity, or the like.
In addition, it is possible to adjust the ultraviolet quantity to be emitted by the printing section ultraviolet irradiator 22 based on the information.
Next, in the paper ejecting section B, when the printed object 1a is passed from the printing section gripper 11 of the last (downstream) impression cylinder 2 to the paper ejecting section gripper 12 attached to the chains 5, it is gripped by the paper ejecting section gripper 12, and conveyed according to movement of the chains 5.
Then, in the collecting portion 7, the paper ejecting section gripper 12 releases the printed object 1a, thereby collecting the printed object 1a (product) at a predetermined position.
According to the ultraviolet irradiation method using the printing press 102, since the ultraviolet quantity to be emitted by the printing section ultraviolet irradiator 22 is adjusted based on the ultraviolet quantity received by the printing section ultraviolet receiver 22a from the printing section ultraviolet irradiator 22, a sufficient quantity of ultraviolet can be securely emitted, so that incomplete curing of the ultraviolet curable ink can be prevented.
The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments.
For example, in the printing press 100 according to the first embodiment, eight impression cylinders 2 and four sets of printers are disposed (see Figure 1), but the number is not particularly limited. Incidentally, this holds true for the printing press 101 according to the second embodiment and the printing press 102 according to the third embodiment.
In the printing press 100 according to the first embodiment, the printing section ultraviolet receiver 22a is attached to the printing section gripper 11 of the fifth impression cylinder 2 from the upstream side, and the printing section ultraviolet irradiator 22 is attached to a position corresponding to the printing section ultraviolet receiver 22a, but, in the printing section A, the printing section ultraviolet receiver 22a and the printing section ultraviolet irradiator 22 are not necessarily essential to the printing section A.
In addition, the mounting positions of the printing section ultraviolet receiver 22a and the printing section ultraviolet irradiator 22 are not limited, and the mounting number thereof may be two or more.
In the printing press 100 according to the first embodiment, the paper ejecting section ultraviolet receiver 21a is attached to the paper ejecting section gripper 12, and the paper ejecting section ultraviolet irradiator 21 is attached to a position corresponding to the paper ejecting section ultraviolet receiver 21a, but, in the paper ejecting section B, the mounting positions of the paper ejecting section ultraviolet receiver 21a and the paper ejecting section ultraviolet irradiator 21 are not limited, and the mounting number thereof may be two or more.
In the printing press 100 according to the first embodiment, the printing section ultraviolet receiver 22a is attached to an approximately central position of the printing section gripper 11, and the paper ejecting section ultraviolet receiver 21a is attached to an approximately central position of the paper ejecting section gripper 12, but the mounting position of the ultraviolet receiver to the gripper is not limited to the center.
In addition, a plurality of ultraviolet receivers may be attached to one gripper.
In the printing press 100 according to the first embodiment, the types of the paper ejecting section ultraviolet receiver 21a and the printing section ultraviolet receiver 22a are not specifically limited, and commercially-available ones can be used according to situations. Incidentally, this holds true for the printing press 101 according to the second embodiment and the printing press 102 according to the third embodiment.
Similarly, the paper ejecting section ultraviolet irradiator 21 and the printing section ultraviolet irradiator 22 are not specifically limited, either, and commercially-available ones can be used according to situations.
In addition, adjustment of the ultraviolet quantities of the paper ejecting section ultraviolet irradiator 21 and the printing section ultraviolet irradiator 22 may be performed by an operator, or may be performed by a robot or the like wirelessly via a computer, based on the ultraviolet quantity displayed on the display unit of the CPU.
Further, the printing section gripper 11 and the paper ejecting section gripper 12 are not particularly limited, either, and commercially-available ones can be used according to situations. Incidentally, this holds true for the printing press 101 according to the second embodiment and the printing press 102 according to the third embodiment.
In the printing press 100 according to the first embodiment, it is preferred that after the printed object 1a is obtained, post-process be performed on the printed object 1a. In this case, a printed object having excellent decorativeness can be obtained.
The post-process can be silk-screen printing, flexography, roller coating, coating, molding, or the like, for example.

Industrial Applicability

The present invention is used as a printing press applying ultraviolet curable ink to a substrate. According to the printing press of the present invention, a sufficient quantity of ultraviolet can be securely emitted, so that incomplete curing of the ultraviolet curable ink can be prevented.

Reference Signs List

1...substate,
1a...printed object,
2...impression cylinder,
3...blanket cylinder,
3a, 3b, 3c...plate cylinder,
4... groove,
5...chain,
7...collecting portion,
11...printing section gripper (gripper),
12...paper ejecting section gripper (gripper),
21...paper ejecting section ultraviolet irradiator (ultraviolet irradiator),
21a...paper ejecting section ultraviolet receiver (ultraviolet receiver),
22...printing section ultraviolet irradiator (ultraviolet irradiator),
22a...printing section ultraviolet receiver (ultraviolet receiver),
31...anilox roller,
32...doctor blade,
33...ink chamber,
35...finisher roll,
100, 101, 102...printing press,
A...printing section,
B...paper ejecting section,
C...light receiving portion.

Claims

A printing press (100) comprising:
a printing section A provided with a plurality of impression cylinders (2) to which a gripper (11) gripping and guiding a substrate (1) is attached, and a printer brought into adjacent contact with the impression cylinder (2) and printing ultraviolet curable ink onto the substrate (1), thereby making a printed object (1a) ; and

a paper ejecting section (B) provided with a chain (5) to which a gripper (12) for gripping and guiding the printed object (1a) is attached, wherein:
an ultraviolet irradiator (21, 22) for irradiating the printed object (1a) with ultraviolet is disposed; and

a printing section ultraviolet receiver (21a, 21b) capable of receiving ultraviolet is attached to the gripper (11, 12) facing the ultraviolet irradiator (21, 22).
The printing press (100) according to claim 1, wherein:
the printing section A is provided with a printing section ultraviolet irradiator (22) for irradiating the printed object (1a) guided by the impression cylinders (2) with ultraviolet; and

a printing section ultraviolet receiver (22a) capable of receiving the ultraviolet is attached to the gripper (12) in the printing section (A).
The printing press (100) according to claim 1, wherein:
the paper ejecting section (B) is provided with a paper ejecting section ultraviolet irradiator (21) for irradiating the printed object (1a) guided by the chain (5) with ultraviolet; and

a paper ejecting section ultraviolet receiver (21a) capable of receiving the ultraviolet is attached to the gripper (12) in the paper ejecting section (B).
The printing press (100) according to claim 1, wherein:
the printing section (A) is provided with a printing section ultraviolet irradiator (22) for irradiating the printed object (1a) guided by the impression cylinders (2) with ultraviolet;

a printing section ultraviolet receiver capable of receiving (22a) the ultraviolet is attached to the gripper (11) in the printing section (A);

the paper ejecting section (B) is provided with a paper ejecting section ultraviolet irradiator (21) for irradiating the printed object 1a guided by the chain (5) with ultraviolet; and

a paper ejecting section ultraviolet receiver (21a) capable of receiving the ultraviolet is attached to the gripper (12) in the paper ejecting section (B).
The printing press (100) according to claim 2 or 4, wherein the printing section ultraviolet receiver (22a) is attachable and detachable to the printing section gripper (11).
The printing press (100) according to claim 3 or 4, wherein the paper ejecting section ultraviolet receiver (21a) is attachable and detachable to the paper ejecting section gripper (12).
The printing press (100) according to claim 2 or 4, wherein a groove (4) capable of housing the printing section gripper (11) and the printing section ultraviolet receive (22a) is formed in the impression cylinder (2).
The printing press (100) according to claim 2 or 4, wherein the printing press is a sheet-fed gravure printing press (102) or a sheet-fed flexographic press (101).
The printing press (100) according to claim 3 or 4, wherein the printing press is a sheet-fed offset printing press (100).
An ultraviolet irradiation method of a printing press using the printing press (100) according to claim 2 or 4, wherein
based on an ultraviolet quantity received by the printing section ultraviolet receiver (22a) from the printing section ultraviolet irradiator (22), an ultraviolet quantity to be emitted by the printing section ultraviolet irradiator (22) is adjusted during operation.
An ultraviolet irradiation method of a printing press using the printing press (100) according to claim 3 or 4, wherein
based on an ultraviolet quantity received by the paper ejecting section ultraviolet receiver (21a) from the paper ejecting section ultraviolet irradiator (21), an ultraviolet quantity to be emitted by the paper ejecting section ultraviolet irradiator (21) is adjusted during operation.
The ultraviolet irradiation method according to claim 10 or 11, wherein information on the ultraviolet quantity is transmitted to a CPU, and an ultraviolet quantity is adjusted based on the information.