JPH05237984A - Offset press - Google Patents

Abstract

PURPOSE:To enhance dimensional accuracy in a printing direction at the time of the printing of a pattern by an offset press and to ensure the dimensional accuracy of an object to be printed having thickness irregularity. CONSTITUTION:A spring 8 is inserted in the lower part of a rack gear 11 to always eliminate the gap between the rack gear 11 and a pinion gear 10 and the irregularity of the film thickness of an object to be printed is absorbed. Further, an intaglio fixing stand 4 and a substrate fixing plate 6 are moved by a quantity corresponding to the difference between the moving distances of the pinion gear 10 and a transfer roll at the time of one revolution by a geared motor 13 or the transfer roll is thermally expanded to perform fine adjustment to ensure dimensional accuracy in a printing direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an offset printing machine capable of forming a fine pattern such as a color filter of a liquid crystal display.

[0002]

2. Description of the Related Art In recent years, fine pattern forming techniques typified by semiconductors have been required in various fields. In these fields, photolithography technology using a photosensitive resin has been conventionally used. This is a process in which a photosensitive resin is applied onto a material to be patterned, a pattern is formed through a mask on the material, the underlying layer is etched with an etching solution of the underlying material, and then the photosensitive resin is removed. .. On the other hand, a printing method has been established which can form a large-area pattern at low cost, although the pattern accuracy is poor. Printing methods include intaglio printing (commonly known as gravure) and lithographic printing.
The four mainstream methods are (commonly known as offset printing), letterpress printing (commonly known as letterpress) and stencil printing (commonly known as screen printing). The present invention relates to offset printing such as intaglio and letterpress. Conventionally, in intaglio offset printing, a glass intaglio plate or the like is used, and after supplying the printing ink to the intaglio plate, the ink is once transferred to a transfer roll whose surface is made of silicon rubber, and then transferred onto a printing medium such as paper or glass. A method of transferring and printing more is used [for example, Japanese Patent Laid-Open No. 62-
94341 and Mikiya Shimada: The Institute of Electronics, Information and Communication Engineers, C
PM90-24 (1990)]. Further, in the case where the printing pattern is also a pattern parallel to the printing direction, it has become possible to use up to about 10 μm by using an intaglio prepared by dry etching (for example, JP-A-3-221516).

[0003]

However, photolithography is effective for forming a pattern of a small area with a line width of micron or less like a semiconductor, but a line width of several μm to several tens of μm. Therefore, it takes a lot of man-hours to form a large-area pattern, and the facilities are large, which results in a high cost. On the other hand, in printing methods such as intaglio printing, the equipment is simple, the number of steps is small, and it is easy to form a line width (about 10 μm) pattern to some extent on a large area, but it is difficult to secure dimensional accuracy in the printing direction. Had a problem. For example, in the case of intaglio offset printing of a pattern having a length of 10 cm in the printing direction, the average pattern length is about 10 cm ± 100 μm, and the variation there is about ± 70 μm, which is a very bad value compared to the lateral direction (about ± 5 μm). Becomes In view of the above problems, it is an object of the present invention to provide an offset printing machine capable of suppressing the average pattern length in the printing direction within about several μm with respect to the original size.

[0004]

In order to achieve the above object, the present invention provides an offset printing machine in which a moving distance at the time of printing is restricted between a transfer roll and a printing stage via a pinion gear and a rack gear. Insert a spring, rubber, etc. so that there is no gap between the pinion gear and the pinion gear at all times, and always maintain a fixed distance regardless of the thickness of the material to be printed. It is also possible to adjust the moving distance of the transfer roll and finely adjust the dimension in the printing direction by moving the material to be printed and the printing plate by a small amount in the printing direction during transfer or controlling the temperature of the transfer roll. It was done.

[0005]

In the present invention, the gap between the rack gear and the pinion gear described above is prevented by a spring or the like, so that the variation in the moving distance of the transfer roll due to the variation in the thickness of the material to be printed can be eliminated. In the conventional type, when the thickness of the printing material is thick, the engagement between the rack gear and the pinion gear becomes shallow,
There is a gap between the gears, which causes dimensional variations during printing. On the other hand, in the configuration of the present invention, since the meshing position between the rack gear and the pinion gear is constantly constant, dimensional accuracy in the printing direction can be secured. Further, since the surface of the transfer roll is made of silicon rubber, it is difficult to grasp the true radius of gyration when it is rotated under pressure. Therefore, remove the rack gear, measure the distance for one rotation in a free state, and move the material and printing plate in the printing direction by a small amount during one rotation of the transfer roll in the printing direction by the distance difference from when controlled by the rack gear. By performing the correction, the residual stress on the silicone rubber can be eliminated and fine pattern printing can be performed.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of an intaglio offset printing machine according to an embodiment of the present invention, and FIG. 2 is a side view. 1 and 2, 1 is a pulse motor, 2 is a ball screw, 3 is a moving base, 4 is an intaglio fixing base, 5 is a quartz intaglio,
6 is a substrate fixing base, 7 is a glass substrate, 8 is a spring, 9 is a pin, 10 is a pinion gear, 11 is a rack gear, 12 is a transfer roll, 13 is a geared motor, 14 is a screw, 15 is an air cylinder, and 16 is a linear. Weiss Ladder, 17 is a side frame. The manufacturing method of the dot type color filter for liquid crystal is shown below. First, the structure of the intaglio offset printing machine used will be explained. A uniaxial stage with a pulse motor 1 and a ball screw 2 (for example, MONO-COMP manufactured by NSK)
Mount the moving table 3 on the (O table). Further, in order to prevent distortion due to load, a Linear Weisladder 17 (for example, manufactured by Nippon Thomson) was provided under both sides of the moving table. The intaglio fixing base 4 and the board fixing base 6 connected by the geared motor 13 and the screw 14 are mounted on the moving base, and the rack gear 11 is mounted on the moving base next to the fixed base via the spring 8 and the pin 9. Installed. The rack gear 11 can slide in the vertical direction by the pin 9 but cannot move in the horizontal direction, and is statically placed in a balanced position by the spring 8. However, rubber could be used instead of the spring 8. The quartz intaglio plate 5 was vacuum-chucked on the intaglio platen 4, and the glass substrate 7 was vacuum-chucked on the substrate platen 6. The pinion gear 10 is provided on the side frame 17
Transfer roll 12 which is fixed with and the surface is covered with silicone rubber and has a motor lamp (not shown) for temperature adjustment inside.
And an intaglio offset printing machine constituted by a mechanism for moving up and down with an air cylinder 15 was used. The used quartz intaglio 5 is a dot pattern of the liquid crystal color filter 60 × 80
A 15 μm deep pattern was used. First, the moving distance between the transfer roll 12 and the pinion gear 10 was adjusted. After temporarily lowering the rack gear 11 to disengage from the pinion gear 10, the transfer roll 12 was lowered onto the quartz intaglio 5 and rotated once to check the moving distance of only the transfer roll. Next, with the rack gear 11 and the pinion gear 10 meshed with each other, the movement distance per one rotation was similarly examined. However, the radius of the transfer roll was designed in advance so that the moving distance of only the transfer roll 12 would be slightly shorter. If the difference in the moving distance from the time when the gear is inserted is 200 μm or more, the fixed stand is moved by the geared motor 13 by the difference in the moving distance while the transfer roll 12 makes one rotation, and the moving distances of both are matched (quartz. The intaglio and glass substrate also move at the same time). On the other hand, the movement distance is 2
In the case of 00 μm or less, the temperature of the transfer roll was raised by a heater lamp and the transfer roll was thermally expanded to control the moving distance (when 200 μm or more, it was difficult to control the transfer roll diameter by thermal expansion). After filling the quartz intaglio 5 with ink for a color filter using a doctor knife, the transfer roll was rolled on the quartz intaglio 5 in the same manner as in conventional offset printing, and the ink was transferred onto silicon rubber. It was rolled on the glass substrate 7 and the ink was transferred onto the glass substrate to form a color filter pattern on the glass substrate 7. As for the dimensional accuracy of the pattern when printing 100 sheets, the average value is 150.001 mm (standard deviation 6 μm) in the printing direction of 150 mm, and the average value is 120.002 m in the horizontal direction of 120 mm.
m (standard deviation 4 μm) and printed dot shape is 56 × 75
It was μm. In a conventional offset printing machine (calibration machine, etc.), the standard deviation in the printing direction is 70μ because the gap between the rack gear and the pinion gear changes due to the variation in the thickness of the glass substrate.
It was as large as about m, and the dot pattern was easy to deform. Further, in the case of offset printing that does not have a guide mechanism using a rack gear and a pinion gear, the average value was 150.12 mm (standard deviation of about 90 μm), and the dimensional accuracy in the printing direction was even worse. In addition to the intaglio printing method, the offset printing such as the letterpress printing method also improved the printing dimensional accuracy by the same method.

[0007]

INDUSTRIAL APPLICABILITY As described above, the present invention makes it possible to greatly improve the dimensional accuracy at the time of printing by the intaglio offset printing machine described above, particularly the dimensional accuracy in the printing direction which has been considered impossible by the conventional printing method. did. Furthermore, the reproducibility of dot patterns and horizontal lines has also been dramatically improved compared to the conventional method. In particular, when a glass substrate such as a liquid crystal having a non-uniform plate thickness is used as a printing medium, the offset printing machine of the present invention is characterized in that the variation in plate thickness does not affect the printing dimension accuracy.

[Brief description of drawings]

FIG. 1 is a front view of an intaglio offset printing press according to an embodiment of the present invention.

FIG. 2 is a side view of an intaglio offset printing press according to an embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Pulse motor, 2 ... Ball screw, 3 ... Moving base, 4 ... Intaglio fixing base, 5 ... Quartz intaglio, 6 ... Substrate fixing base, 7 ... Glass substrate, 8 ... Spring, 9 ... Pin, 10 ...
Pinion gear, 11 ... Rack gear, 12 ... Transfer roll,
13… Geared motor, 14… Screw, 15… Air cylinder, 16… Linear Weisladder, 17… Side frame.

Claims (3)

[Claims] 1. In an offset printing machine in which a moving distance at the time of printing is regulated between a transfer roll and a printing stage via a pinion gear and a rack gear, a spring or rubber or the like is inserted below the rack gear, and a gap is always provided between the pinion gear and the pinion gear. The offset printing machine is characterized in that it is not possible to do. 2. The temperature of the transfer roll is controlled so that the radius of gyration of the transfer roll can be finely adjusted.
Offset printing machine described. 3. An offset printing machine in which a moving distance at the time of printing is regulated by a pinion gear and a rack gear between a transfer roll and a printing stage, in which a material to be printed and a printing plate are made movable in a printing direction. Characteristic offset printing machine.