JP2004001326A - Ink jet recorder - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To harden ink surely by irradiating an ink jet print part with UV-rays efficiently a plurality of times. <P>SOLUTION: The ink jet recorder moves an ink jet recording head 6 in the main scanning direction, moves a print medium 22 in the subscanning direction and ejects UV-curing ink from the nozzle of the ink jet recording head 6 thus printing a line, corresponding to the print width of the ink jet recording head 6, at a time on the print medium 22. UV-ray irradiators 12 and 14 for curing ink are provided on the side of the ink jet recording head 6. UV-ray irradiation range of the UV-ray irradiators 12 and 14 is set not smaller than two times of the print width of the ink jet recording head 6. Consequently, the UV-ray irradiators 12 and 14 can irradiate both the current print area of the ink jet recording head 6 and the print area of a previous line by a single scanning motion of the ink jet recording head 6. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an ink jet recording apparatus provided with an ultraviolet irradiation device.
[0002]
[Prior art]
Japanese Patent Application Laid-Open No. Sho 60-132767 discloses an ink jet printer in which a UV lamp (ultraviolet lamp) is provided beside a recording head so as to irradiate ultraviolet rays once to an ink-attached portion immediately after printing. In addition, the publication discloses an ink jet printer in which an ultraviolet lamp having a length sufficient to irradiate substantially the entire area of the recording paper is fixedly set on the discharge side of the recording paper.
[0003]
[Problems to be solved by the invention]
In the configuration in which a UV lamp is provided beside the recording head and the ink immediately after printing is irradiated with ultraviolet light only once, the ink may not be reliably cured by one irradiation. However, the recording head must be moved in the main scanning direction again, and the printing efficiency is degraded. In addition, in the configuration in which the UV lamp is provided on the recording paper discharge side, the ink adhering to the recording paper cannot be immediately irradiated with ultraviolet rays, so that the ink may bleed before the ultraviolet irradiation. was there.
An object of the present invention is to solve the above problems.
[0004]
[Means for Solving the Problems]
In order to achieve the above object, the present invention is to move an ink jet recording head in a main scanning direction, move a printing medium in a sub scanning direction, and discharge ultraviolet curable ink from nozzles of the ink jet recording head to a printing medium. In an ink jet recording apparatus that performs printing one line at a time corresponding to the print width of an ink jet recording head, an ultraviolet irradiation device for curing ink is provided beside the ink jet recording head, and the irradiation range of the ultraviolet irradiation device is adjusted by the ink jet recording head. The printing width is set to be at least twice as large as the printing width so that both the printing area of the ink jet recording head and the printing area of the previous line can be irradiated with ultraviolet rays for curing the ink.
Further, according to the present invention, the ultraviolet irradiation device is provided on both sides of the ink jet recording head.
[0005]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings.
In FIG. 2, reference numeral 2 denotes a Y rail of the ink jet recording apparatus, which is fixed to a machine body (not shown). Reference numeral 4 denotes a head carriage mounted on the Y rail so as to be able to reciprocate along the Y rail, and the ink jet recording head 6 is mounted on the head carriage. A plurality of ink ejection heads 8 are formed on the inkjet recording head 6.
[0006]
On both sides of the recording head 6 in the main scanning direction, ultraviolet irradiation devices 12 and 14 having UV lamps (ultraviolet lamps) 10 are provided. Reference numeral 16 denotes an X rail, which is disposed below the Y rail 2 at a right angle to the Y rail 2 and supported by an airframe. A platen 18 having a vacuum function is attached to the X rail 16 so as to be able to reciprocate along the X rail 16. A plurality of suction pads 20 provided with a plurality of suction holes are attached to the platen 18, and a printing medium 22 made of a hard plate material such as a printed board is fixed on the suction pads 20 by suction. Have been. The platen 18 and the head carriage 4 are each linked to a driving device controlled by a controller.
[0007]
An ultraviolet curable ink is supplied to the ink jet recording head 6, and the ink is ejected from the nozzles of the ink ejection head 8 to perform printing on the print medium 22 on the platen 18. The elongated nozzle arrangement surface of the ink discharge head 8 is set to be horizontal to the mounting surface of the platen 18 and the longitudinal direction of the nozzle arrangement line is set substantially parallel to the longitudinal direction of the X rail 16. As shown in FIG. 1, the ink discharge heads 8 are arranged in parallel so that their print width is (L).
[0008]
The elongated UV lamps 10 of the ultraviolet irradiation devices 12 and 14 are arranged so that the longitudinal direction thereof is substantially parallel to the longitudinal direction of the ink discharge head 8. The length of the UV lamp 10 in the longitudinal direction is set to be about twice the length of the ink discharge head 8, and the ultraviolet irradiation in the direction perpendicular to the main scanning direction along the Y rail 2 of the recording head 6 is performed. The width is set to twice (2L) the print width (L) of the head. The ultraviolet irradiation areas of the ultraviolet irradiation devices 12 and 14 include an area overlapping the printing area of the recording head 6 in the main scanning direction and an extended area extending by (L) width to a printing area preceding the area in the sub-scanning direction. It is configured. That is, the ultraviolet irradiation regions of the ultraviolet irradiation devices 12 and 14 are set so as to cover two lines. Note that the ultraviolet irradiation regions of the ultraviolet irradiation devices 12 and 14 may be further extended to cover three lines or more.
[0009]
Next, the operation of the present embodiment will be described.
First, a plate-shaped printing medium 22 such as a printed board is set on the platen 18. When the printing operation starts, the head carriage 4 is reciprocated in the main scanning direction along the Y rail 2 under the control of the controller. On the other hand, the platen 18 facing the recording head 6 is driven in the sub-scanning direction along the X rail 16. At this time, an ultraviolet curable ink droplet is ejected from the recording head 6, and printing is performed line by line on the printing medium 22 on the platen 18, and a printing portion on the printing medium 22 immediately after printing and a printing on the previous line are performed. The part is irradiated with ultraviolet light by a UV lamp 10.
[0010]
The printing operation will be described in more detail with reference to FIG.
As shown in FIG. 3A, when the printing operation is started, the recording head moves leftward from the home position at the right end of the Y rail 2 and discharges ink from the ink discharge head 8 to print the print medium. Printing of one line is executed in the area of {circle around (1)}. At this time, the printing area (1) is irradiated by the ultraviolet irradiation device 14 to cure the ink. When printing of the area (1) of the print medium 22 is completed, the print medium 22 is conveyed by one line in the direction of the arrow. Next, as shown in FIG. 3B, the recording head 6 moves rightward from the left side position of the Y rail 2 on the return path, and prints one line of printing in the area (2) of the printing medium 22. Execute. At this time, the region (1) of the previous line is irradiated twice by both the ultraviolet irradiation devices 12 and 14, and the printing region (2) is irradiated once by the ultraviolet irradiation device 12.
[0011]
As a result, the print area (1) of the print medium 22 is in the first reciprocating main scan of the recording head 6 for two irradiations by the ultraviolet irradiation device 14 and three irradiations by the ultraviolet irradiation device 12 for a total of three times. UV irradiation is performed. At this stage, in the printing area (2), the number of ultraviolet irradiations is one by the ultraviolet irradiation device 12. In the second forward path of the recording head 6 in the main scanning direction, the ultraviolet irradiation devices 12 and 14 perform two irradiations of ultraviolet light on the print area (2) of the print medium 22, as shown in FIG. A total of three ultraviolet irradiations are performed, including the previous irradiation. The number of ultraviolet irradiations in the printing area (3) is one by the ultraviolet irradiation device 14.
[0012]
In the second return pass of the recording head 6 in the main scanning direction, two ultraviolet irradiations are performed on the print area (3) of the print medium 22 by the ultraviolet irradiation device areas 12 and 14, and the number of ultraviolet irradiations in the print area (3) is performed. Is three times, including the previous minute. At this stage, the number of ultraviolet irradiations in the area (4) is one, as shown in FIG. Assuming that the print area (4) is the last print area on the print medium 22, the controller transports the print medium 22 by one print area in the print medium transport direction, and moves the recording head 6 to the left. Moving without any operation, the two ultraviolet irradiation devices 12 and 14 irradiate the print area {circle around (4)} twice with ultraviolet light. As a result, the cumulative number of ultraviolet irradiations in all of the print areas (1), (2), (3), and (4) on the print medium 22 becomes three.
[0013]
As described above, in a device configured to provide a UV curing device (lamp) beside the head and to cure the ink immediately after printing, the length of the UV curing device is set to be longer than the printing width of the recording head. By increasing the size twice or more, even in the next printing after moving the printing width of the substrate etc., the first printed position can be illuminated by the lamp again, so it is more reliable than one irradiation. Ink can be cured. By providing lamps on the left and right sides of the head, the number of irradiations can be increased, and bidirectional printing can be supported.
[0014]
The present embodiment has a structure in which four inkjet heads are sandwiched by UV lamps provided on both sides. However, the present invention is not particularly limited to this, and a structure in which one is provided beside the head is particularly problematic. There is no. Although the head is moved in the scanning direction in a reciprocating manner, the head may be printed in one direction, and need not be moved in both directions. Further, basically, after printing with ink, the UV lamp follows and cures the ink.
[0015]
In addition, the same position may be printed in a reciprocating manner (double printing), or the same four colors may be provided for each of the four heads this time so that double printing can be performed in one scan. . In the structure of the present embodiment, since a lamp having a width twice as large as the printing width is used, irradiation can be performed three times even in normal bidirectional printing, so that the ink can be cured properly.
[0016]
【The invention's effect】
Since the present invention is configured as described above, it is possible to efficiently irradiate the ultraviolet ray to the printing section with the ultraviolet curable ink.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a recording head according to the present invention.
FIG. 2 is a diagram illustrating the appearance of an inkjet recording apparatus.
FIG. 3 is an explanatory diagram of the present invention.
[Explanation of symbols]
2 Y rail 4 Head carriage 6 Recording head 8 Ink ejection head 10 UV lamp 12 UV irradiation device 14 UV irradiation device 16 X rail 18 Platen 20 Suction pad 22 Print medium

Claims (2)

The inkjet recording head is moved in the main scanning direction, the printing medium is moved in the sub-scanning direction, and one line corresponding to the printing width of the inkjet recording head is printed on the printing medium by discharging the ultraviolet curable ink from the nozzles of the inkjet recording head. In an ink jet recording apparatus that performs printing at a time, an ultraviolet irradiation device for curing the ink is provided beside the ink jet recording head, and the irradiation range of the ultraviolet irradiation device is set to be at least twice the printing width of the ink jet recording head, An ink jet recording apparatus wherein both a print area of a print head and a print area of a previous line can be irradiated with ultraviolet rays for curing ink. The inkjet recording apparatus according to claim 1, wherein the ultraviolet irradiation device is provided on both sides of the inkjet recording head.

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