JPH01110964A - Electrostatic type ink-jet recording apparatus - Google Patents

Abstract

PURPOSE:To consistently form a minimum and stable meniscus at the tip of each nozzle by consistently driving pressure electrodes for pressure injecting ink disposed in ink feed passages or driving the same in synchronism with recording electrodes disposed in the vicinity of the respective nozzles formed in a nozzle plate connected to the openings of the ink feed passages. CONSTITUTION:Once ink is fed into ink feed passages 4, it is polarized to positive and negative ions; the former secure to the internal walls, while the latter become fluidized. Therefore, when DC voltage is impressed to the pressure electrodes 5 and recording electrodes 7 in synchronism with these two electrodes or is impressed in a consistent manner to the pressure electrodes 5 from a driving circuit 5a, the fluidized negative ions are attracted to the recording electrode 7 side, and the fluidity of ink liquid is thus generated by virtue of the attracting force acting on these negative ions. In addition, when voltage is impressed to a back electrode 8, an electric field is formed, and electric charge is injected into the meiscuses formed in the respective nozzles 6a, whereby ink is pulled to the back electrode 8 side in form of a drip so as to allow a recording paper 7 provided in front of the back electrode 8 to be printed therewith.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electrostatic ink jet recording apparatus, and more particularly to a spatula section of an electrostatic ink jet recording apparatus.

Figure 4 is a perspective view showing an example of a conventional electrostatic inkjet recording device. An upper plate and a lower plate made of an insulator to be formed; 13, a recording north pole arranged in large numbers on the lower plate 12b; 14, a back electrode arranged opposite to the supply port 11; 15, the back electrode 14; a recording paper 16 moving along the recording electrode 1;
I81 to supply high voltage to selected electrodes of 3! It is a source of encouragement. In the electrostatic type or inkjet recording device described above, when ink is injected into the ink supply port 11, a continuous meniscus is formed in the ink supply port, and one or more selected electrodes of the recording electrode 13 are supplied with a voltage higher than the drive power supply 16. When a voltage is supplied, the ink near the selected recording electrode is pulled toward the back electrode 14, ejected from the ink supply port 11, and adheres to the recording paper 15 provided in front of the back electrode 14 for recording. The information is printed.

In the electrostatic inkjet recording device configured in this way, since the ink supply port 11 is slit-shaped, an ink meniscus is formed uniformly, and a high electric field is required to eject ink near a selected recording electrode. Alternatively, there are disadvantages in that a long pulse width is required, the power supply configuration is complicated, and the recording speed cannot be improved.

In general, in an electrostatic inkjet recording device, the first factor in increasing ejection efficiency is how to form an ink meniscus. and how to focus the electric field strength generated by the recording electrode. Therefore, a vibrator is provided in the head section, and the vibrator causes unevenness on the ink liquid surface of the slit-shaped opening to promote the formation of an ink meniscus due to electrostatic force.
Alternatively, methods have been proposed in which this formation process is shortened or omitted, but in this case, since the ejection occurs randomly, it is difficult to create a constant unevenness on the meniscus, and it is difficult to create uniform irregularities in the meniscus. was also difficult to deal with.

The present invention was made in view of the above-mentioned circumstances.
In particular, this was done with the aim of forming a stable meniscus, concentrating the electric field strength, and improving the injection efficiency.

Structure In order to achieve the above-mentioned object, the present invention provides an electrostatic inkjet recording device that uses electrostatic attraction to eject ink from an ink ejection port and adheres it to recording paper, which comprises: a body having an ink supply path; , comprising a nozzle plate in which a plurality of nozzles are integrally formed, the nozzle plate is joined to the opening of the ink supply path, recording electrodes are arranged around each nozzle of the nozzle plate, and A pressing electrode for pressing and discharging ink in the ink supply path is disposed in the ink supply path, and the pressing electrode is driven constantly or in synchronization with the recording electrode. be. Hereinafter, the present invention will be explained based on examples.

FIG. 1 is a main part configuration diagram for explaining an embodiment of an electrostatic inkjet recording apparatus according to the present invention, FIG. 2 is a perspective view of the head section, and FIG. 3 is a formation of a meniscus in the inkjet head. This is a diagram for explaining the process. In the figure, 1 is a head tank, 2 is a first substrate having a large number of grooves 2a extending in the longitudinal direction, and 3 is a second substrate disposed opposite to the grooves 2a. Both substrates form the body of the inkjet head. 4 is an ink supply path formed by the groove 2a of the first substrate 2 and the second substrate 3; 5 is a pressing electrode disposed on the second substrate 3 corresponding to the groove 2a; 5a; is connected to the pressing electrode 5,
A drive circuit 6 is for applying a voltage to the pressing electrode 5 in synchronization with a recording electrode 7, which will be described later, or constantly. A nozzle plate is joined to correspond to each nozzle 6a, 7 is a recording electrode arranged around the nozzle 68 of the nozzle plate 6, 8 is a back electrode, and 9 is a recording paper provided in front of the back electrode 8. When ink is supplied to the ink supply path 4, the ink is polarized into positive and negative ions, as shown in FIG. ions) are selectively adsorbed, and ions of opposite sign (negative ions) form an electric double layer. In this state, positive ions are fixed to the inner wall, and negative ions can be considered to have fluidity.

Therefore, the pair of electrodes disposed at both ends of the ink supply path 4, that is, the pressing electrode 5 and the recording electrode 7,
When a DC voltage is applied from the drive circuit (5a) to the press electrode 5 in synchronization with these image electrodes or on a regular basis 1, fluid negative ions are attracted to the recording electrode 7 side, and these Flow occurs in the ink liquid due to the force of the pickpocket. Furthermore, when a voltage is applied to the back electrode 8, an electric field is formed,
An electric charge is injected into the ink meniscus formed in the nozzle 6a, and the ink is pulled toward the back electrode 8 in a spindle shape, and is printed on the recording paper 7 provided in front of the back electrode 8.

The ink consumed by the ejection is sequentially supplied, and the tip of the nozzle 6a has 1. A meniscus of minimum curvature is always formed.

Note that the groove portion 2a becomes a 60 μm groove when the pitch is, for example, 120 μm, and is processed by dicing.

It can be easily manufactured by glass etching.

Further, the press electrode can be easily manufactured by printing on the second substrate 3 or by using a PCB substrate.

Effects As is clear from the above description, according to the present invention, a stable meniscus with minimum curvature can always be formed at the nozzle tip, and injection efficiency can be improved.

[Brief explanation of the drawing]

FIG. 1 is a main part configuration diagram for explaining an embodiment of an electrostatic inkjet recording apparatus according to the present invention, FIG. 2 is a perspective view of the head section, and FIG. 3 is a formation of a meniscus in the inkjet head. FIG. 4, which is a diagram for explaining the process, is a main part configuration diagram for explaining an example of a conventional inkjet head. 1... Head tank, 2... First board, 2a...
- Groove, 3... Second substrate, 4... Ink supply path, 5
... Pressing electrode, 5a... Drive circuit, 6... Nozzle plate, 6a... Nozzle, 7... Recording electrode, 8...
... Back electrode, 9... Recording paper. Figure 1 ↓ Figure 2 Figure 3 ↓ Figure 4

Claims (1)

[Claims] In an electrostatic inkjet recording device that ejects ink from an ink ejection port using electrostatic attraction and adheres it to recording paper, a nozzle that has a body having an ink supply path and a plurality of nozzles integrally formed. Consisting of a plate,
The nozzle plate is joined to the opening of the ink supply path, recording electrodes are arranged around each nozzle of the nozzle plate, and a recording electrode is provided for pressurizing and ejecting the ink of the ink supply path into the ink supply path. An electrostatic inkjet recording device characterized in that a pressing electrode is provided, and the pressing electrode is driven constantly or in synchronization with the recording electrode.