JPH11314346A - Method and apparatus for screen printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately cut by screen printing a relatively thin paper, and accurately sending a printing paper while scarcely elongating or contracting it in a method for screen printing a paper surface. SOLUTION: The method for screen printing to screen print a rolled paper in the state that the paper is stopped while drawing the rolled paper comprises the steps of using a drawing roll 15 intermittently rotating by winding the paper dawn from the rolled paper on an outer periphery, drawing the paper of a predetermined length by rotation of the roll 15 from the rolled paper to send it to a printing position, and printing the paper fed to a printer 10 at the time of stopping the roll 15. Suction holes are provided on the outer periphery of the roll 15 to suck the external air via the holes to preferably bring the sheet into close contact with the outer periphery of the roll.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing method and a screen printing apparatus for performing screen printing on a paper surface.

[0002]

2. Description of the Related Art As a conventional screen printing method, a flat plate is used as a printing table, a low-viscosity glue is applied thereto, and printing paper is pasted thereon, and a screen stencil is placed on the paper. There is a method in which ink is extruded from a screen stencil with a wooden board or a plastic squeegee and printed. This method is still widely used when printing relatively large-sized paper on thin paper of 60 g / m ² or less, and is suitable for printing small lots of many kinds of products.

[0003] In addition, printing paper printed by a screen printing machine is manually placed in a drying table and dried. Furthermore, printing is performed by a screen printing machine, and the printing paper is automatically put into a drying table and dried, or a roll-wrapped printing paper is used, and the printing paper is fed out, followed by printing, drying, and cutting processes. There is also a method.

[0004] However, these methods have many problems in the accuracy of positioning the printing position on the printing paper. recent years,
Screen printing paper is often subjected to two-color, three-color printing, or the like, and multi-color printing may be performed at a fixed position after screen printing. For this purpose, printing must be performed at a fixed position every time. For this reason, in a screen printing machine in which printing, drying and cutting are automated, thin paper of 60 g / m ² or less has not been put into practical use due to the structure of the machine.

Factors preventing the automation of thin paper of 60 g / m ² or less include the following. That is,
Screen printing machines, which are completely automated from printing to drying, stack printing paper of a certain size and send it to the printing unit with an automatic paper feeder one by one, and print it. During the application, the printing paper must be precisely positioned in each case in a fixed position. It is difficult to accurately register this position because the thinner the printing paper, the less rigid the paper. Regardless of the printed matter which does not have a problem with the printing accuracy like the one-color printing wrapping paper, when two-color printing or three-color printing is performed, the product is not completed unless the register is registered each time.

[0006] Further, the printing paper is conveyed to a drying furnace by a conveyor or the like and dried. However, there are unstable factors such as the printing paper floating or reversing on the conveyor in the drying process, and the workability is impaired. Is the current situation. On the other hand, even in a printing method in which a roll-wound base paper is used as a base paper for printing, the printing is performed while sequentially feeding the roll, and drying and cutting are performed, the pitch from the preceding printing surface to the succeeding printing surface is also reduced. There is a problem with accuracy.

When screen printing is performed on a roll-wound base paper, the printing roll-wound base paper performs a continuous intermittent motion that repeats moving / stopping, moving / stopping. When the intermittent motion is stopped, printing and cutting are performed simultaneously, and the printing paper moves to the next printing position and cutting position at the same time as printing and cutting are completed. A conventional pulling roll serving as a driving means for continuously repeating the intermittent motion is configured to feed a printing paper sandwiched between upper and lower rolls. In this case, the contact width of the upper and lower rolls in contact with the printing paper is at most only 10 to 20 mm. For this reason, the interval from the first roll roll paper to the printing, drying, and cutting device can be efficiently performed with this pulling roll alone, intermittent feeding is repeated while maintaining the feeding accuracy, and the pitch accuracy between the printing surface and the printing surface is set to a high level. It is virtually impossible to maintain. Moreover, the printed paper has the property of stretching and shrinking in the drying step, and the amount of expansion and contraction is not constant. Therefore, the entire printing paper cannot be continuously and intermittently fed while maintaining high accuracy.

[0008]

SUMMARY OF THE INVENTION Accordingly, the present invention provides a screen printing method which can perform screen printing on relatively thin paper, and furthermore, the printing paper does not easily expand and contract, and can be sent with high precision to perform accurate cutting. It is an object to provide a printing method and an apparatus therefor.

[0009]

In order to solve the above-mentioned problems, the present invention has the following configuration. First, a screen printing method according to the present invention is a screen printing method in which screen printing is performed while the base paper is stopped while the base paper is pulled out, wherein the base paper drawn from the roll base paper is wound around the outer peripheral surface. A base paper of a predetermined length is drawn out of the roll-wound base paper by the rotation of the drawer roll and sent to a printing position, and printing is performed on the base paper sent to the printing apparatus when the drawer roll is stopped. It is characterized by:

Further, a screen printing apparatus according to the present invention provides a base paper feeding apparatus for feeding a rolled base paper, a tension adjusting apparatus for adjusting the tension of the fed base paper, and performs screen printing on the base paper with a predetermined size. A printing device, a mark marking device for marking a control mark on the base paper, a drawer roll that wraps the printed printing paper around the outer peripheral surface and rotates intermittently, and a sensor that detects the mark attached by the mark marking device; And a cutting device for cutting the printing paper at a predetermined cutting position based on the detection result of the sensor.

If an infrared dryer for drying the printing paper held on the outer peripheral surface of the drawer roll is provided on the outer peripheral portion of the drawer roll, the ink on the printing paper can be dried at a preferable drying speed. Can be. Further, the drawer roll is formed in a hollow, and a plurality of suction holes communicating with the inside and outside are provided on the outer peripheral surface thereof, and a suction device for sucking air in the hollow portion of the drawer roll is provided.
Since the printing paper is in close contact with the outer peripheral surface of the roll, slack or the like hardly occurs, and the printing paper can be fed accurately. Further, for adjusting the cutting position, it is preferable to provide a guide roll capable of adjusting a bypass amount of the printing paper between the drawer roll and the blade of the cutting device.

As described above, in order to produce screen printing paper with stable accuracy regardless of the thickness and the material of the paper, the method of intermittently feeding the printing paper with high accuracy by nipping the printing paper between the upper and lower two rolls Therefore, there is a problem in improving the method of feeding printing paper. In the present invention, in order to improve this point, a roll having a large diameter is used as a pull-out roll, and the printing paper is drawn in a state where the printing paper is wound on the surface thereof. Drying can also be performed.

According to the method of the present invention, since the printing paper is intermittently fed and dried while being wound on the surface of the drawer roll which rotates intermittently, there is no change due to expansion and contraction of the printing paper, and wrinkles and curls are generated on the paper. Screen printing can be performed regardless of the thickness and material of the printing paper.
Hereinafter, a specific example will be described in detail.

[0014]

FIG. 1 shows the structure of a screen printing apparatus according to the present invention.
Is provided with a feeding device 2 for holding a rolled base paper R and continuously feeding the base paper P from the roll. The feeding device 2 includes a feed belt 4 that circulates and moves along guide rollers 6 in contact with the outer peripheral surface of a rolled base paper R rotatably supported by a shaft 3. This is a device for continuously feeding a base paper P from a rolled base paper R by moving a feed belt 4 with a driving roller. This feeding speed can be adjusted by adjusting the rotation speed of the drive roller. These guide rollers 6,... Are attached to a frame that rotates about the axis of the lowermost guide roller due to expansion and contraction of the air cylinder 5, and as the remaining amount of the roll-wound paper decreases, the cylinder is moved. The belt 4 can be extended so that the belt 4 can be brought into contact with the rolled paper under the same pressure.

The base paper P fed by the feeding device 2
Is sent to the printing device 10 via the tension adjusting device 9. The printing apparatus 10 includes a printing table 10a, a screen stencil 1
0b and its mounting hardware, a squeegee 10c, an ink return 10d, etc., and the amount of movement of the squeegee 10c and the ink return 10d depends on the length of printing on the base paper (the length of the printing surface). Adjustable.
The printing base paper is stopped while printing is performed by the printing apparatus 10. The tension adjusting device 9 includes guide rollers 9a and 9b before and after the position is fixed, and a movable roller 9c that moves between the guide rollers 9a and 9b.
Is urged downward at a predetermined pressure by elastic urging means (not shown). This biasing force is adjustable.

The printing by the printing apparatus 10 is performed with the base paper stopped as described above. During this printing, the base paper is continuously fed from the feeder 2, so that
The base paper is loosened in front of the printing apparatus. In order to prevent this, the tension adjusting device 9 is provided in this device, and the moving roller 9c moves downward at a constant pressure to increase the amount of detour of the base paper. It is kept in tension and never sags.

The marking device 1 is located downstream of the printing device 10.
2 are provided. The mark marking device 12 detects this by a photoelectric tube sensor to be described later, and sets the timing of cutting. The mark marking device 12 is marked with a black transfer foil on the space between the front and rear adjacent printing surfaces. . Specifically, similar to the foil stamping printing method using a normal transfer foil,
The mark is formed by pressing the transfer foil against the paper surface using a hot stamp. The shape of this mark may be, for example, a rectangular mark having a width of about 0.2 mm. The mark marking device 12 is used while being fixed at a predetermined position, but is provided so as to be able to translate in the direction in which the printing paper surface moves.
This is because when the print size of the printing paper surface is changed, the pitch between the printing surfaces also changes, so that it is necessary to adjust the position of the mark.

This apparatus is provided with a drawing roll 15 for drawing out the base paper intermittently. Drawer roll 1
5 is formed in a hollow drum shape, and its outer peripheral surface 15a is provided with a large number of through holes communicating with the inside and outside, and a rotary shaft 16 is provided at the center of the roll. This rotating shaft 1
6 is rotatably supported by a bearing (not shown), and is intermittently rotated by a predetermined amount in a direction of an arrow at a predetermined interval by a driving device (not shown). The rotation shaft protrudes from both ends of the roll 15, one shaft is formed in a hollow pipe shape, and an intake pipe 17 is connected to the end of the shaft so as to be relatively rotatable. This suction pipe 17 is provided with a suction pump 18
When the suction pump is operated, the air in the roll 15 is sucked and discharged, so that the outside air is sucked from the through hole in the outer peripheral surface of the roll, and the printing paper is moved to the outer peripheral surface of the roll by the pressure. They adhere.

As long as the circumference of the drawer roll 15 is as large as possible, more stable drawing accuracy can be ensured. However, the larger the circumference, the larger the diameter of the roll, so that the workability and operability deteriorate. Generally, the diameter of the roll 15 is 1 to 3
m is preferable, but is not limited thereto. Further, the height of the highest part of the outer peripheral surface of the drawer roll 15 is at least 100 times higher than the printing table of the printing apparatus 10.
It is desirable that the distance is at least mm or lower. The reason is that when the printing paper is pulled out by the drawer roll 15 with a certain tension,
This is because they move smoothly while constantly sliding along the surface of the printing table. Also, when the screen stencil is separated from the printing paper at the end of printing, there is an effect of preventing the printing paper from sticking to and hanging from the screen stencil.

A drying device (heater) 20 is attached to the outer peripheral portion of the drawer roll 15 so as to surround the roll surface along the circumference. As a heat source of the drying device 20, it is preferable to adopt an electric heat infrared radiation method from the viewpoint of safety, operability, drying effect and the like. The drying devices 20 are attached at a total of four locations at a distance from each other so that the infrared radiation temperature can be adjusted for each one.

On the downstream side of the drawer roll 15, guide rolls 23, 23 for guiding the movement of the printing paper P 'on which the base paper has been subjected to predetermined printing are provided. This guide roll 2
Reference numeral 3 is for guiding the printing paper P 'wound around the drawer roll 15 and sent from the roll to a roll device in front of the cutting device.

The printing paper P ′ sent from the drawer roll 15 is sent to a cutting device 30 via a differential pressing roller device 27, a cutting position adjusting roll 28, and a cutting differential pressing roller device 29. It is cut exactly at the middle of the printing surface. A photoelectric sensor 35 for detecting the mark on the printing paper is provided in the vicinity of the exit of the differential pressing roll device 27. The differential pressing roll device 27 is configured to move the guide roll 2 from the drawer roll 15.
The printing paper passed through the upper and lower rolls 27a, 27
By rotating with the pinch at b, the slack of the printing paper on the upstream side is prevented, and the rotating shaft has a structure that slips when a force greater than a predetermined tension acts. I have. The cutting position adjusting roll 28 is
It is provided so that the vertical position can be adjusted. By adjusting the vertical position, the amount of detour of the printing paper can be adjusted, and the cutting position on the printing paper can be adjusted.

Further, a differential pressing roll device 29 for cutting is provided.
Is to feed the printing paper P 'to the cutting position with high precision by pressing the printing paper between the upper and lower rolls 29a and 29b and rotating the rotation of the rotation shaft. It has a structure to do. Cutting device 3
When the cut portion of the printing paper sent to 0 reaches the cutting position of the cutting device, the cutting blade 30a descends and cuts the printing paper. This cutting device is operated based on the mark detection output of the photoelectric sensor 35, and thereby cuts precisely at a predetermined cutting position (usually at the intermediate position between the printing surfaces).

Next, the results of actual printing using the screen printing apparatus of the present invention will be specifically described. A Japanese paper with a basis weight of 40 g has a slit width of 800 mm,
The roll was wound into a roll to form a roll-shaped base paper. The roll-wound base paper was previously passed through a printing unit (printing position by a printing device), a drawer roll unit, a guide roll unit, and the like to a cutting unit by a cutting device. The length of the base paper from the rolled base paper to the cutting section was about 17 m.

The screen printing size is 560 mm × 790
mm. The printed matter was solid printing, and the screen stencil mesh was 300. The drawer roll 15 has a surface length of 1000 mm and a diameter of 2000 mm. Further, the diameter of the suction hole (the above-mentioned through hole) provided on the surface of the drawer roll 15 was a drill hole of 0.5 mm, and it was divided into 350 mm each from the center of the drawer roll surface length, and seven pieces were provided at 100 mm intervals. Further, the number of intake holes with respect to the circumference is 43
There were four. The circumferential pitch between the intake holes is about 62.
It was 8 mm. A turbo fan having a suction port of 150 mm was used as a suction pump.

The printing paper is pulled out to about 8
The film was wound to 5%, and the intermittent feed amount of the drawer roll was adjusted to 562 mm while performing idle operation, and 2 mm more than the printing length was taken. A servo motor was used as a power source for intermittent feeding of the drawer roll, and the feed amount was instructed by the sequencer S to this servo motor. When a printing end signal is sent from the printing device to the sequencer,
A signal is sent from the sequencer to the servo motor, and the drawer roll operates, and then stops. The sequencer also sends a signal to the printing device to start printing and marking. By precisely repeating these operations, a highly accurate printing paper is completed.

As shown in FIG. 2, a concentric worm wheel 40 is mounted on the rotating shaft of the drawer roll 15 and the rotating shaft 42 of the worm 41 meshes with the rotating shaft of the drawer roll 15 so that the drawer roll 15 can smoothly and accurately intermittently rotate. And the output shaft 46 of the servo motor 45 is transmitted by a chain 47. Such a structure is preferable because the rotation and stop of the drawer roll 15 can be performed with high accuracy.

On the other hand, the movement amounts of the squeegee and the ink return were set to 600 mm. When the squeegee moves on the screen stencil and printing is completed, the rotation of the drawer roll 15 causes the printing paper to move 562 mm, and screen printing and mark printing are performed simultaneously with the completion of the movement of the printing paper. It was confirmed that the device was operating correctly. Further, it was confirmed that the detection mark was printed at an intermediate position of 2 mm between the printing surfaces.

The temperatures of the four heaters of the drying device were set as follows. The set temperatures were 35 ° C. for the first heater, 40 ° C. for the second heater, 45 ° C. for the third heater, and 50 ° C. for the fourth heater in order from the top in the figure according to the properties of the ink. If the ink, which is relatively thick as in screen printing, is dried rapidly, only the surface of the ink is dried and the inside is not dried, and the printed surface is deteriorated at a later date, causing trouble. To avoid this, the stepwise set temperatures described above were preferred.

The ink used was an aqueous ink. The color used was crimson. The viscosity of the ink is 500 cps, taking into account the properties and performance of the machine and the number of meshes on the screen stencil.
Of viscosity. Initial printing speed of 500 sheets per hour
It was a sheet. The full-scale operation was started while confirming that the intermittent feeding state and the drying state of the printing paper, the tension of the printing paper, the photoelectric tube sensor for detecting the mark, and the operating state of the cutting device were good.

By the operation of the suction pump, the printing paper was brought into close contact with the surface of the drawer roll to be integrated. Printing paper is
Wrinkles and curls did not occur, but rather an ironing effect was observed. From these results, it was convinced that the avenue of versatile and versatile screen printing with one mechanical device was opened.

[0032]

As is apparent from the above description, according to the present invention, good screen printing can be performed regardless of the quality of paper and the thickness of paper, and further, for example, printing on elastic plastic materials. For example, printing can be performed on a much wider range of materials than before. In addition, since the paper can be fed with high precision, it is possible to obtain high-quality printing and printing colors, and it is also possible to print with water-based ink, which has been impossible in the past.

[Brief description of the drawings]

FIG. 1 is a configuration explanatory view illustrating an embodiment of a screen printing apparatus of the present invention.

FIG. 2 is an explanatory view of a drive device of the drawer roll.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Screen printing device 2 Feeding device 9 Tension adjusting device 10 Printing device 12 Mark marking device 15 Pull-out roll 20 Drying device 27 Nipping roller device 29 Nipping roller device 30 Cutting device

Claims (6)

[Claims] 1. A screen printing method for performing screen printing in a state in which a roll-wound base paper is pulled out while stopping the base paper, wherein the base paper drawn from the roll-wound base paper is wound around an outer peripheral surface and intermittently rotated. A screen wherein the base paper having a predetermined length is drawn from the roll-wound base paper by rotation of the drawer roll and sent to a printing position, and printing is performed on the base paper sent to the printing device when the drawer roll is stopped. Printing method. 2. A drawer in which the base paper wound on the outer peripheral surface of the roll is brought into close contact with the outer peripheral surface of the roll by suctioning through a suction hole provided on the outer peripheral surface of the drawer roll. 2. The screen printing method according to 1. 3. A base paper feeding device for feeding a rolled base paper, a tension adjusting device for adjusting the tension of the fed base paper, a printing device for performing screen printing on the base paper with a predetermined size, and a control mark on the base paper. Mark-marking device, a drawer roll that wraps the printed printing paper around the outer peripheral surface and rotates intermittently, a sensor that detects the mark added by the mark-marking device, and a printing paper based on the detection result of the sensor. And a cutting device for cutting the sheet at a predetermined cutting position. 4. The screen printing apparatus according to claim 3, wherein an infrared dryer for drying the printing paper held on the outer peripheral surface of the drawer roll is provided on an outer peripheral portion of the drawer roll. 5. A drawer roll is formed in a hollow shape, a plurality of suction holes communicating inward and outward are provided on an outer peripheral surface thereof, and a suction device for sucking air in a hollow portion of the drawer roll is provided. The screen printing device according to claim 3. 6. The screen according to claim 3, wherein a guide roll for adjusting a cutting position by adjusting a detour amount of paper is provided between the drawer roll and a blade body of the cutting device. Printing device.