JPS6120755A - Multi-jet deflecting device - Google Patents

Abstract

PURPOSE:To prevent the drop of the recording quality without cost-up by providing first deflecting electrodes rectangular to the direction of the mutual movement of the record paper and the head and secod deflecting electrodes parallel to said direction. CONSTITUTION:The ink-jet head is provided with nozzles 2, charging electrodes 3 giving a charge to the ink droplet 5 from the nozzles 2, first deflecting electrodes 4 opposing rectangularly to the direction of the movement of the recording paper 8, second deflecting electrodes 9 parallel to the direction of the movement and gutters 7. As a base plate a di-acrylphthalate resin including glass fibers is used, the electrodes 3, 4, 9 and gutters 7 are formed in a body by a compression molding method, together with the lead-pattern of the electrodes on the back surface by a photo-etching method. Thereby the drop of the recording quality is prevented without cost-up and the change of the recording speed is capable to follow the change of the ink characteristics.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a multi-jet deflection device, and particularly to a multi-jet deflection device that controls the charge of ink droplets ejected from a plurality of nozzles and electrostatically deflects them to achieve high-speed The present invention relates to a deflection device for a multi-nozzle inkjet recording device that obtains high-quality images.

[Conventional technology]

As a conventional multi-nozzle inkjet recording device using a charge deflection method, for example, ultrasonic vibration is applied to pressurized ink in a head.

The ink droplet is ejected as a stream of ink droplets from a nozzle installed at the tip of the head, and a charging electrode gives the ink droplet a charge according to the recording signal voltage, and the ink droplet is passed through an electric field formed by a deflection electrode. There is one in which the ink droplets are deflected according to the electric charge, and these ink droplets are deposited in a straight line (in the scanning direction) on a recording paper provided facing each other to form an image.

An outline of this type of unidirectional nozzle inkjet recording apparatus will be explained with reference to FIGS. 4 to 7. FIG. 4 shows a schematic configuration of a multi-nozzle inkjet recording apparatus, in which 1 is an ink droplet generator, 2 is a nozzle, 3 is a charging electrode that charges the ink droplets, and 4 is a deflection electrode that deflects the charged ink droplets 5.

5 is a recording ink droplet, 7 is a gutter for collecting unnecessary ink droplets 6, and 8 is a recording paper.

In the above configuration, ultrasonic vibration is applied to the pressurized ink supplied to the ink droplet generator 1, and the nozzle 2 at the tip of the ink droplet generator 1 is ejected as ink droplets 5 in a jet shape. When these ink droplets 5 pass through the charging electrode 3, they are charged according to the recording signal voltage. An electrostatic deflection field generated between a pair of flat deflection electrodes 4 on either side of the flying ink droplet 5 downstream thereof deflects the charged ink droplet 5 according to its charge. These ink droplets 5 are spread out in a straight line on recording paper 8 disposed opposite to each other. At this time, the unnecessary ink droplets 6 pass between the deflection electrodes 4, are collected by a gutter 7 provided directly opposite the deflection electrodes 4, and are collected by an ink supply device (not shown).

However, in the conventional multi-nozzle inkjet recording device, the direction of deflection of the ink droplets 5 is set perpendicular to the direction of relative movement of the recording paper 8 and the ink droplet generator 1, so the line pattern created by the deflection process is Relative motion will cause it to tilt.

FIG. 5 shows the distribution state of inclined ink droplets. When the recording paper is fed in the Y direction at a constant speed using nozzles A, B, and O having a predetermined recording width, the deflection is from the left to the right in the X direction. That is, when moving from dl to dn, when the ink droplet in dl reaches the recording paper, the drum (81) formed on the recording paper due to sdi moves to the uppermost position, and henceforth dBgdB.
+d4 do y l' s, j sl e 84
forms the image in the lower right corner. This slope is determined by the time required for deflection and the recording paper loading speed.

Figure 6 shows the distribution of ink droplets in the case of sequential scanning (without interlacing mechanism) and in the case of skipping, continuous scanning (interlacing mechanism A9), where the X direction is the deflection direction of the ink droplets, and the Y The direction is the direction in which the recording paper moves. In the case of sequential scanning, as shown in Figure 6 (f), the distance between the ink droplets is narrow, the ink droplets undergo electrostatic interaction, and the air resistance changes directly due to the preceding ink droplets. , recording distortion increases. To prevent this, interlaced scanning is generally performed. Interlaced scanning is a method that divides the scanning of a continuous stream of ink droplets into multiple sections. For example, 3
In the case of allocation to two scanning sections, as shown in FIG. and (Dra) c, f, i are assigned during the third period. This improves the recording distortion described above, but increases the inclination of the recorded dots.

To improve this, Japanese Patent Application Laid-Open No. 57-107855
There is a deflection device shown in the issue. FIG. 7 shows this deflection device, having an upper deflection electrode 11 and a lower deflection electrode 12, each electrode 11.12 having a number of teeth 13.14 with an inclined surface, the teeth of the upper deflection electrode 11 13 faces downward, while the teeth 14 of the lower deflection electrode 12 face upward. These teeth 13.14 are electrically conductive and are connected to the upper deflection electrode 11.
is connected to the 10B potential, and the lower deflection electrode 12 is connected to the ground potential. Space 1 between the sides of teeth 13 and 14
5 forms a deflection area 22 for the ink droplet 21. The right side 16 of each upper tooth 13 and the left side 17 of each lower tooth 14 have a positive slope and define a left deflection region 23 .

The right side surface 18 of each lower tooth 14 and the left side surface 19 of the upper tooth 13 have a negative slope and define a right deflection region 24 . The slope of these left and right deflection areas compensates for the relative movement between the recording paper 20 and the ink drop stream 21.

According to this deflection device, the ink droplets are deflected in the horizontal direction by the left and right inclined deflection areas, and are also deflected in the vertical direction according to the inclination angle, so the above-mentioned problem of forming an image at an angle can be solved. Eliminate.

[Problem that the invention seeks to solve]

However, with the conventional deflection device (Figure 7), the deflection area must be machined at a highly accurate tilt angle, resulting in high costs, and if the processing accuracy decreases, there is a risk that the recording quality will deteriorate. There is. Furthermore, once the inclination angle is set, the amount of deflection in the vertical direction is fixed, making it impossible to follow changes in recording speed, changes in ink characteristics, etc.

[Means and effects for solving the problems] The present invention has been made in view of the above problems.l); It prevents deterioration of recording quality without causing storage and printing, and furthermore, In order to be able to follow changes in characteristics, etc., a first deflection electrode that deflects ink droplets in a direction perpendicular to the direction of relative movement between the recording paper and the ink droplet generator, and a A multi-jet deflection device is provided that includes a second deflection electrode that deflects the drops in the same direction.

In particular, according to the present invention, the following advantages arise by arranging the first deflection electrode at the front stage and the second deflection electrode at the rear stage. That is, since the amount of deflection in the horizontal direction is larger than the amount of deflection in the vertical direction, first, by deflecting in the horizontal direction, the distance between the ink droplets can be increased, thereby weakening the electrostatic force between the ink droplets. .

The multi-jet deflection device according to the present invention will be explained in detail below.

1 to 3 show one embodiment of the present invention.

In the drawings, the same components as in the conventional example are represented by the same reference numerals.

That is, 2 is a nozzle, 3 is a charging electrode that charges the ink droplet 5 ejected from the nozzle, 4 is a first deflection electrode facing at an angle of 90° to the moving direction of the recording paper, and 9 is the recording paper. 7 is a gutter that collects unnecessary ink droplets, and its manufacturing process is as follows: 0) A thermosetting substrate with excellent heat resistance and excellent dimensional stability. The charged electrode 3. is made by compression molding using a mixture of diallyl phthalate resin and glass fiber.
The first deflection electrode 4, the gutter 7, and the second deflection electrode 9 are integrally formed.

(b) Electroless copper plating is applied to the entire surface of the resin substrate, and 1
A 5 μm LD copper plating layer is formed.

(-9 Form an F-photoresist layer by dip coating on the entire surface of the above copper plating layer, place a photomask on top of it, irradiate light, expose the photoresist layer, and leave the unexposed photoresist layer. Remove with developer.

(b) After forming a chromium plating layer with a thickness of S μm and a total plating layer with a thickness of 1 μm on the entire surface by electroplating, the exposed portions of the photoresist 7 are removed and the copper layer is removed with an etching solution.

Through this manufacturing process, the electrode of the hatched portion shown in FIG. 2 (0) e) is formed. Further, a lead pattern is formed on the back side in a similar process.

Through the above steps, only the lower electrode 9a of the second deflection electrode 9 is formed. The upper electrode 9b is formed on another insulating substrate in a similar process, and is opposed to the lower electrode 9a as shown in FIG. This electrode plate is combined with an ink droplet generator (not shown) consisting of a piezoelectric vibrator, an ink chamber, and a nozzle plate to form an inkjet head.

In fact, the nozzle diameter manufactured by the above method was 20 μm.
(dot diameter on recording paper 80 μm), nozzle pitch is 5
1m (during deflection/nozzle), number of nozzles 42 (during recording 210
Using an inkjet head (A4), pressurize the ink to &5-2 from the ink supply bottle and print at 15 m/
The inkjet was ejected at s.C, and the atomization frequency was 125 MP (z, first deflection voltage 2 kV1 charging voltage ±
Recording was carried out under the following conditions: 140 V or less, recording paper feeding speed 3 #c/A 4. In this case, interlaced scanning was performed by skipping 7 dots for 8 dots.

When the second deflection electrode was at 070, the horizontal line was tilted by about 7.9°. As the voltage increases, the amount of vertical deflection increases, and the slope becomes smaller.
At 0v, it became Oa, that is, a horizontal straight line. The position of each dot deviates somewhat from the ideal position, and although this deviation differs depending on the recording pattern, it has been experimentally confirmed that even in the worst case, it can be suppressed to within ±15 μm and there is no problem in practical use. Ta.

In this embodiment, the method of manufacturing the electrode was limited to a method of plating and photo-etching an integrally molded insulating substrate, but the method is not necessarily limited to this.

〔Effect of the invention〕

As explained above, 'According to the deflection device of the multi-nozzle inkjet recording device of the present invention, since the second deflection electrode is provided by an easy manufacturing method, deterioration in recording quality is prevented without increasing cost, and It is possible to follow changes in recording speed, changes in ink characteristics, etc.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, and FIGS. 1(c) and 1(b) schematically show a multi-nozzle jet recording apparatus according to the present invention, and 0) is a plan view. ←) is a cross-sectional view, Figure 2 (10←) f) shows a schematic configuration of the electrode section, 0) is a plan view, (b) and f9 are cross-sectional views, and the third ink jetted from a plurality of nozzles. An explanatory diagram showing a distribution state of droplets. FIG. 6 is an explanatory diagram showing the distribution state of ink droplets by sequential scanning and interlaced scanning. FIG. 7 is a front view showing a deflection device having nine deflection areas that are alternately inclined. Explanation of symbols 1... Ink droplet generator, 2... Nozzle, 3...
Charging electrode, 4... First deflection electrode, 5... Recording ink droplet, 6... Unnecessary ink droplet, 7...
Gutter, 8...Recording paper, 9--Second deflection electrode, 9
m...Lower electrode% 9b...Upper electrode. Figure 1 (A) Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] An ink droplet generating means having a plurality of nozzles, and charging that charges and deflects each ink droplet to join an image formed on a recording paper by one ink droplet flow with an image formed by an adjacent ink droplet flow. , a multi-nozzle inkjet recording apparatus comprising a deflecting means, a means for collecting non-recording ink droplets, and a means for supplying ink at a predetermined pressure to the ink droplet generating means; A first deflection electrode that deflects the ink droplet flow in a direction perpendicular to the direction of relative movement, and a second deflection electrode that deflects the ink droplet flow in the same direction as the relative movement direction. Multi-jet deflection device.