JPH05169622A - Offset printing method and its device - Google Patents

Abstract

PURPOSE:To deal with various kinds of printing demands and needs easily and inexpensively. CONSTITUTION:An ink sheet 42 supported in the plate shape is pressed to a press plate 11 of plate shape to which ink P is applied, and the ink P on the press plate 11 is transferred to the ink sheet 42, and then the ink sheet 42 is pressed to a work 21 to print a print pattern onto the work 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offset printing method suitable for high-precision printing of parts such as a printed wiring board or an image display device, and an apparatus therefor, and more specifically, an offset printing method in which ink transfer means is improved. The present invention relates to a printing method and an apparatus thereof.

[0002]

2. Description of the Related Art Conventionally, for example, an offset rotary press or an offset proof machine has been widely used for this kind of high precision printing.

[0003]

However, in such a conventional rotary offset press or offset proof machine,
Printing may occur due to deformation of the printing plate when the plate-shaped printing plate is wound around the plate cylinder and fixed, deformation of the blanket that transfers ink from the printing plate to the surface of the work, or variation in the relative position between the blanket and the work. In addition to poor image position accuracy and image distortion, the high cost, complicated handling, large machine volume, and other problems cause high-precision printing and small-lot printing. There is a problem that it is difficult to deal with printed matter.

The present invention has been made under the above circumstances, and an object of the present invention is to make it possible to meet various printing demands such as high-precision printing, and it is inexpensive and easy to handle. Another object of the present invention is to provide an offset printing method and its apparatus.

[0005]

In order to solve the above-mentioned problems, the present invention provides a plate-shaped printing plate which is placed on a plate and on which a printing pattern composed of an intaglio, letterpress or planographic plate is formed. A step of applying ink on the surface and applying it, a step of bringing an ink sheet supported in a flat plate shape close to the surface of the plate, a back surface of the ink sheet being pressed, and a surface of the ink sheet and the plate. Contacting the surface of the ink sheet to transfer the ink to the surface of the ink sheet, moving the ink sheet to the surface of the work placed on the work plate, and approaching the surface of the work. A step of pressing the back surface of the ink sheet and bringing the surface of the ink sheet into contact with the surface of the work to transfer the ink on the surface of the ink sheet. In the door printing method.

The present invention also relates to a plate base, a plate-shaped plate placed on the plate base and having a printing pattern formed of an intaglio, letterpress or planographic plate, and an ink on the surface of the plate. And an ink sheet supported in a flat plate shape on the surface of the printing plate on which the ink is spread by the ink spreading means and the surface of the work placed on the work plate. The ink sheet approaching means for relatively approaching each other and the back surface of the ink sheet are pressed, and the surface of the ink sheet is brought into contact with the surfaces of the printing plate and the work, respectively, and ink is applied to the surface of the ink sheet. The offset printing apparatus is provided with a pressing unit that transfers the ink on the surface of the ink sheet to a work.

In this case, a plurality of alignment marks are provided on the ink sheet, the positions of these alignment marks are detected in the state of being brought close to the ink sheet and the printing plate or the work, and printing is performed according to the alignment marks. It is preferable to configure so as to correct the positions of the plate and the work.

[0008]

That is, according to the present invention, an ink sheet supported on a flat plate is pressed against a plate-shaped printing plate on which ink is placed to transfer the ink of the printing plate to the ink sheet, and then the ink sheet. Since the printing pattern is printed by pressing on the work, the deformation of the ink sheet when transferring from the printing plate to the ink sheet and when printing from the ink sheet to the work become almost equal. This enables highly accurate printing on the work.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will now be described in detail with reference to the drawings. FIG. 1 schematically shows the entire structure of an offset printing apparatus according to the present invention, in which 1 is a base. Is.

On the base 1, there is a first moving table 3 capable of adjusting the X-Y2 direction and the rotation angle in a horizontal plane via a first air supply / exhaust system passage 2, and the first moving table 3. With respect to the moving direction of the carrier, which will be described later, and through the second supply / exhaust system passage 4 in the horizontal plane, XY2.
A second moving table 5 whose direction and rotation angle can be adjusted is arranged.

On the first moving table 3, the printing plate 1 is placed.
0 is fixed, and a plate-shaped printing plate 11 is placed on the plate stand 10.
And the surface 11a of the printing plate 11
In, a printing pattern for printing a predetermined image line is formed by using, for example, an intaglio, letterpress or planographic printing plate. On the other hand, a work plate 20 is fixed on the second moving table 5, and a work 21 is placed on the work plate 20.

Reference numeral 30 in the drawing denotes an inking device arranged above the first moving table 3, and this inking device 30
Is internally provided with an ink feeder 31 as an ink supply means.
Have

The ink feeder 31 has an ink pot 32 as an ink containing portion for containing the ink P, and an original roll 3 for taking out the ink P from the ink pot 32.
The original roll 33 is composed of the feed roll 3
4 is provided so as to be able to approach and separate.

The feed roll 34 includes a plurality of the kneading rolls 3 each containing the ink P taken out from the original roll 33.
5, 36 and 37, and the ink P kneaded by these kneading rolls 35, 36 and 37 is made to adhere to a mounting roll 38 facing the lower part of the inking device 30. Have.

That is, the inking device 30 includes the printing plate 11 mounted on the plate table 10 of the first moving table 3.
By moving the surface 11a of the plate A in parallel,
The ink P is applied to the surface 11a of No. 1 through the applying roll 38 and is applied with a uniform thickness. Further, reference numeral 40 in the drawing denotes a carrier positioned correspondingly on the surface 11a of the printing plate 11 placed on the plate table 10 of the first moving table 3.

The carrier 40 includes a work 21 placed on the work plate 20 of the second moving table 5.
As shown in FIG. 2, the rectangular frame 41 and an ink sheet 42 supported in a flat plate shape on the lower surface of the frame 41 are configured so as to be parallel movable toward the side.

The ink sheet 42 is usually made of a synthetic resin sheet having a thickness of about 100 μm, which is easy for ink to adhere to. However, when the positional accuracy and dimensional accuracy of printed lines are required, As shown in 3, thickness 100μm
By forming the synthetic resin layer 43 having a thickness of about 50 μm and the stainless mesh or the porous metal sheet layer 44 having a rigidity higher than that of the synthetic resin having a thickness of about 50 μm, the positional stability with respect to the frame 41 is maintained. Is becoming

Further, reference numerals 50 and 60 in the figure denote first and second pressure devices installed above the first and second moving tables 3 and 5, respectively, and these pressure devices 50 and 60 are rubber rollers 51. , 61.

Next, the printing process on the work by the offset printing apparatus according to the present invention will be described.
The inking device 30 is moved in the direction of arrow A from the standby position shown in FIG. 1, and the ink P is applied to the surface 11a of the printing plate 11 placed on the plate table 10 of the first moving table 3 to obtain a uniform thickness. Serve it.

After the ink P is deposited on the surface 11a of the plate 11, the inking device 30 is returned to the original standby position and, at the same time, the plate placed on the plate table 10 of the first moving table 3 is pressed. The carrier 40 is brought close to the substrate 11.

Then, the surface 11a of the printing plate 11 and the surface 42 of the ink sheet 42 supported by the frame 41 of the carrier 40.
When the distance from a approaches 0.5 to 0.8 mm, the rubber roller 51 of the first pressure device 50 is lowered in the direction shown by the arrow B in FIG. The back surface 42b of 42 is pressed, and the ink sheet 42
And the surface 11a of the printing plate 11 are brought into contact with each other.

In this state, the rubber roller 51 is moved in the direction shown by the arrow C in FIG. 1 to transfer the ink P applied to the surface 11a of the printing plate 11 to the surface 42a of the ink sheet 42.

After raising the rubber roller 51 and returning it to the original standby position, the carrier 40 is placed on the work plate 20 of the second moving table 5 and the carrier 2 is placed on the work plate 20.
1 is moved to a position corresponding to 1, and the distance between the surface 42a of the ink sheet 42 and the surface of the work 21 is 0.5 to 0.8.
When approaching about mm, the rubber roller 61 of the second pressure device 60 is lowered in the direction shown by the arrow D in FIG. 1, and the back surface of the ink sheet 42 is pressed by this rubber roller 61, and the surface of the ink sheet 42 is pressed. 42a and surface 21a of work 21
Contact with.

In this state, the rubber roller 61 is moved in the direction shown by the arrow E in FIG.
By transferring the ink P of a to the surface of the work 21, a predetermined image line is printed on the surface 21a of the work 21.

At this time, the ink sheet 42 has a synthetic resin layer 42A having a thickness of about 100 μm, as shown in FIG.
It is formed with a stainless steel mesh or a porous metal sheet layer 42B having a rigidity higher than that of a synthetic resin having a thickness of about 50 μm.
Does not cause abnormal deformation, residual strain, or the like due to the pressing force of the rubber rollers 51 and 61, and therefore a highly accurate image line is printed on the surface 21a of the work 21.

By the way, in such a printing process,
The mechanism for transferring the ink from the printing plate 11 to the ink sheet 42 or the work 2 due to the influence of the temperature, the operating time or the rest time.
When the printing mechanism for No. 1 is deformed, the horizontal relative positions of the plate 11 and the ink sheet 42 and the ink sheet 42 and the work 21 change, and the position of the surface of the ink sheet 42 to which the ink adheres changes. Alternatively, the position of the image line printed on the work 21 may change.

Next, for the ink sheet 42, the printing plate 1
The operation of positioning 1 will be described with reference to FIGS. 4 to 6. As shown in FIG.
Two cross-shaped alignment marks 45, 46 are provided in b.
Is provided.

As a general apparatus for detecting the position of the image such as the cross mark, as shown in FIG. 5, a plurality of image sensors 70, 71, 72, 73 are provided.
Is used, and the sensor head 74 is movable in the direction of arrow 75.

Mark bases 76 and 77 are fixed to the base 1, and reference marks 78 and 79 respectively provided on the mark bases 76 and 77 are attached to the image sensors 70 and 73.
The alignment marks 45 and 46 of the ink sheet 42 are detected by the image sensors 71 and 72 while being fixed with reference to the reference marks 78 and 79.

Using such an image position detecting device,
To position the plate 11 with respect to the ink sheet 42,
As shown in FIG. 6, the carrier 40 located on the upper side of the printing plate 11 is moved so that the mark base 7 is removed without the carrier 40.
The positions of the alignment marks 80, 81 of the printing plate 11 detected by the image sensors 71, 72 with reference to the reference marks 78, 79 on the reference marks 6, 77, and as shown in FIG.
If the difference between the positions of the alignment marks 45 and 46 of the ink sheet 42 detected by the image sensors 71 and 72 is a predetermined value, the position of the moving table 3 is not adjusted, but this difference is a predetermined value. When it is larger than the value, the moving table 3 is moved by an actuator (not shown) in the directions of arrows X, Y, and θ shown in FIG. 6 for positioning.

On the other hand, the work 2 for the ink sheet 42
Also in the case of 1, positioning is performed by moving the moving table 5 using the sensor head 74 described above.

By the way, after printing an image line on the surface of the work 21, the ink sheet 42 separates from the work 21,
A part of the ink thin film adheres to the surface 42a of the ink sheet 42, and a pattern, that is, an afterimage, is formed by the adhered ink. Therefore, in the next printing, the ink sheet 42 and the plate 11 If the alignment of (1) is not performed accurately, this afterimage and the ink newly transferred from the printing plate 11 will not accurately overlap.

As a result, the surface 4 of the ink sheet 42 is
In 2a. A bloated pattern is formed, and an image line different from that of the previous work 21 is printed on another work 21.

Therefore, the work 21 and the ink sheet 42 are
Although the contact with the printing plate 11 and the ink sheet 42 is made only once,
Since the contact is repeated, the position of the ink sheet 42 and the printing plate 11 is strictly aligned, and high-precision image lines can be printed.

Further, when the image lines to be printed are highly precise and delicate, or when overprinting or multicolor printing is required, the carrier 100 as shown in FIGS. 7 and 8 is used.

This carrier 100 comprises an ink sheet 102 stretched over a frame 101, a synthetic resin layer 103 having a thickness of about 100 μm, a metal backup sheet 104 having a thickness of about 200 to 500 μm, a stainless mesh or Support sheet 105 made of porous metal sheet
Etc., and is stretched on the frame 101 in two directions orthogonal to each other with a tension of 1.5 kg / cm 2.

Accordingly, the rigidity of the backup sheet 104 forming the ink sheet 102 is high, and the ink adhering to the surface of the synthetic resin layer 103 surely retains the shape of the printed line of the work 21. Surface 2
It is possible to print a fine line with high accuracy on 1a.

However, according to the above configuration, for example, when the carrier 40 shown in FIG. 2 is used and the maximum dimension of the image line printed on a relatively small wiring board is 80 mm, the positional accuracy of about ± 20 μm is obtained. Was obtained.

Further, using the carrier 100 shown in FIG. 7,
± 5 when the maximum size of the printed line is 80 mm
In the case of approximately μm and 150 mm, a positional accuracy of approximately ± 7 μm was obtained.

Further, particularly in the case of a large work 21 having an outer dimension of more than 500 mm or when the ink used has a large adhesive force, the first or second pressurizing device 50, 6 is used.
The ink sheet 42 can be easily separated from the surface 11a of the printing plate 11 or the work 21 by swinging the carrier 40 in the moving direction according to the movement of the rubber rollers 51 and 61 of 0.

In the above embodiment, the printing plate 1
1 and the base 1 supporting the work 21 are fixed, and the ink sheet 42 is moved left and right or up and down by the carrier 40 as shown in FIG.
Although the plate 11 and the work 21 are alternately brought close to each other, it goes without saying that the base 1 side may be moved. In this case, only one of the pressure devices 50 and 60 can be moved. Good.

[0042]

As is apparent from the above description, according to the present invention, an ink sheet supported on a flat plate is pressed against a flat plate-shaped printing plate on which ink is placed, and the ink of the printing plate is printed on the ink sheet. Then, the ink sheet is pressed against the work to print the print pattern on the work, so when transferring from the printing plate to the ink sheet and when printing from the ink sheet to the work. Since the deformation of the ink sheet is almost the same in the above, it is possible to prevent fatal defects such as the deformation of the blanket and the deformation of the printing plate in the conventional offset rotary press or offset proofing machine, and moreover, it is simple and inexpensive. It has a structure, is easy to handle, and can perform highly accurate printing on a work.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an embodiment of an offset printing apparatus according to the present invention.

FIG. 2 is a perspective view showing an example of a carrier with its surface facing upward.

3 is a cross-sectional view of a main part taken along the line AA of FIG.

FIG. 4 is a perspective view showing a state where alignment marks are formed on the back surface of the carrier.

FIG. 5 is a perspective view of a main part of the alignment apparatus.

FIG. 6 is a perspective view of a printing plate and a moving table.

FIG. 7 is a perspective view showing another example of the carrier with the surface facing upward.

8 is a cross-sectional view of a main part taken along the line BB of FIG.

[Explanation of symbols]

10 ... Plate stand, 11 ... Plate, 11a ... Surface, 20 ... Work plate, 21 ... Work, 21a ... Surface, 30 ... Inking device, 40 ... Carrier, 41 ... Frame, 42 ... Ink sheet, 45, 46, 80 , 81 ... Alignment marks, 5
0, 60 ... Pressure device, 70, 71, 72, 73 ... Image sensor, 78, 79 ... Reference mark, P ... Ink.

Claims (4)

[Claims] 1. A step of applying ink onto a surface of a plate-shaped printing plate which is placed on a plate table and on which a printing pattern composed of an intaglio plate, a relief plate or a planographic plate is formed, and a step of applying the ink to the surface of the plate. A step of bringing the ink sheet supported in a flat plate shape close to each other, and pressing the back surface of the ink sheet and bringing the surface of the ink sheet into contact with the surface of the printing plate to transfer the ink to the surface of the ink sheet. The step of moving the ink sheet to the surface of the work placed on the work plate, and pressing the back surface of the ink sheet close to the surface of the work, and the surface of the ink sheet and the work. The step of bringing the surface of the ink sheet into contact with the surface of the ink sheet and transferring the ink on the surface of the ink sheet. 2. A printing plate, a plate-shaped printing plate which is placed on the printing plate and on which a printing pattern composed of an intaglio, letterpress or planographic printing plate is formed, and ink is applied to the surface of the printing plate. The ink depositing means for attaching and the ink sheet supported in a flat plate shape relative to the surface of the printing plate on which the ink is deposited by the ink depositing means and the surface of the work placed on the work plate, respectively. Ink sheet approaching means for approaching and pressing the back surface of the ink sheet, and contacting the surface of the ink sheet with the surfaces of the printing plate and the work, respectively, to transfer the ink to the surface of the ink sheet, An offset printing apparatus comprising: a pressing unit that transfers the ink on the surface of the ink sheet to a work. 3. An ink sheet comprising a synthetic resin sheet and a stainless mesh or porous metal sheet layer, or a synthetic resin layer, a metal backup sheet layer, and a stainless mesh or porous metal sheet layer. The offset printing apparatus according to claim 2, wherein the offset printing apparatus is any one of the printed sheets. 4. An ink sheet is provided with a plurality of alignment marks, the positions of these alignment marks are detected in a state of being brought close to the ink sheet and the plate or the work, and the plate and the plate are aligned with the alignment mark. The offset printing apparatus according to claim 2, wherein the offset printing apparatus is configured to correct the position of the work.