JPH0970974A - Electrostatic ink jet recording head - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrostatic ink jet recording head relatively easy to produce and achieved in miniaturization. SOLUTION: An ink chamber storing ink containing charged toner, the slit like ink passages communicating with the ink chamber and the ink emitting orifices 8 provided to the leading ends of the ink passages are provided. Further, the emitting electrodes 2a-2h provided in the vicinity of the ink emitting orifices 8 and forming electric fields energizing emitting force to the charged toner contained in the ink accumulated in the ink passages and emission control electrodes 3a, 3b forming electric fields preventing the emission of charged toner from the ink emitting orifices 8 together provided to the emitting electrodes 2a-2h are provided. The emitting electrodes 2a-2h and the emission control electrodes 3a, 3b are laminated and arranged through an insulating layer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic ink jet recording head, and more particularly to an electrostatic ink jet recording head which ejects charged toner by the action of an electric field to perform a recording operation.

[0002]

2. Description of the Related Art As an electrostatic ink jet recording head of this type, there is one disclosed in JP-A-61-57343. The one described in this publication includes an ink chamber having an ink introduction port for temporarily storing ink, an ink flow path and a nozzle communicating with the ink chamber, and an ejection hole provided at the tip of the nozzle. Here, the bottom surface of the ink chamber and the bottom surface of the ink flow path and the nozzle are formed in a straight line on the same surface in consideration of flow resistance and the like. Of these, a signal electrode for controlling ink ejection is provided at the tip of the nozzle, while an auxiliary electrode is provided in the ink chamber or ink flow path.

An electric field is formed by applying a predetermined voltage to the signal electrode and the auxiliary electrode, and the charged ink accumulated in the nozzle portion is ejected by the action of this electric field. In addition, after the ink is ejected, a member formed of a porous body is provided in the ink chamber or the ink flow path in order to make up for the shortage of ink in the nozzle portion. Was effectively supplied to.

[0004]

However, in the above-mentioned conventional example, it is necessary to dispose the porous body in the ink chamber or the ink flow path in the manufacturing process, which causes the inconvenience or formation of complicated manufacturing process. There was the inconvenience that high precision was required. Further, since the signal electrode and the auxiliary electrode are provided on the same surface and are spaced apart from each other so that they are not short-circuited, there is a disadvantage that the entire head becomes large.

[0005]

The object of the present invention is to improve the disadvantages of the conventional example, and in particular, the manufacturing process is relatively easy, and
It is an object of the present invention to provide an electrostatic ink jet recording head which is downsized.

[0006]

According to a first aspect of the present invention, there is provided an ink chamber for storing ink containing charged toner, a slit-shaped ink channel communicating with the ink chamber, and a tip of the ink channel. And a corresponding ink ejection hole. Also, an ejection electrode that is provided in the vicinity of the ink ejection hole and forms an electric field that applies an ejection force to the charged toner contained in the ink that has accumulated in the ink flow path, and a charging electrode that is provided in parallel with this ejection electrode And a discharge control electrode that forms an electric field that blocks discharge of toner. The ejection electrode and the ejection control electrode are stacked and arranged with an insulating layer interposed therebetween.

In the present invention, as shown in FIG. 2, for example, the insulating layer Z ₁ is formed after the ejection electrode 2c is formed on the substrate 1, for example.
Is formed, the ejection control electrode 3b is formed on the insulating layer Z _{1 at} a position overlapping with the ejection electrode 2c, and further, for example, the insulating layer Z ₂ is formed on the ejection control electrode 3b and then these electrodes 2c are formed. , 3b to be overlapped with the flow path partition 7 and the ink discharge hole 8
Is provided.

According to a second aspect of the present invention, in the electrostatic ink jet recording head according to the first aspect, among the surfaces surrounding the ink flow path, the surface is connected to an ink chamber connecting surface and an ink chamber connecting surface. An electrophoretic electrode for energizing the electrophoretic migration of the charged toner is provided on at least one pair of side surfaces facing each other.

According to a third aspect of the present invention, in the electrostatic ink jet recording head according to the first aspect, among the surfaces surrounding the ink flow path, the surface is connected to the connecting surface to the ink chamber and the connecting surface to the ink chamber. Electrophoresis electrodes for urging the electrophoretic migration of the charged toner are arranged on the upper and lower surfaces, and a supporting member for the electrodes arranged on the upper surface is provided between the electrophoresis electrode arranged on the upper surface and the ink flow path. It has a configuration that it is provided.

According to the second or third aspect of the invention, when a predetermined voltage is applied to the migration electrode on the surface surrounding the ink flow path, the charged toner in the ink flow path is electrophoretically moved to the vicinity of the ink ejection hole. It

According to the fourth aspect of the present invention, the electrode arranged on the upper surface of the ink flow path and the supporting member are integrally formed.

In the present invention, for example, the PSP method (Photo Sel method) is used.
ectiove plating, APE method (Additiive Photo Etchin
Electrodes for migration of charged toner are integrally formed on the support member by g) or Mold-n-Plate method.

According to a fifth aspect of the invention, the ejection electrode is formed in a strip shape along the ink movement direction of the ink flow path.

In the present invention, for example, a plurality of strip-shaped ejection electrodes are formed in parallel.

According to a sixth aspect of the invention, a plurality of strip-shaped ejection electrodes are formed in parallel on the substrate, and the ejection control electrodes are formed in a strip shape orthogonal to the plurality of ejection electrodes.

In the present invention, the ejection operation by the plurality of ejection electrodes is controlled by one ejection control electrode.

According to a seventh aspect of the invention, in the electrostatic ink jet recording head according to the sixth aspect, a plurality of ejection electrodes and one ejection control electrode are set as one set, and at least two sets are formed in parallel on the substrate. At the same time, the corresponding ejection electrodes of each set are short-circuited by strip-shaped short-circuit members provided in parallel with the ejection control electrodes.

In the present invention, the number of ejection electrodes for one set is sufficient for the contact with the external head driving device, regardless of the number of ejection electrodes.

According to an eighth aspect of the invention, a part of the migration electrode is exposed in the ink flow path.

In the present invention, when a voltage is applied to the migration electrode, excess counter ions (having a polarity opposite to that of the charged toner) generated near the ejection electrode after the charged toner flies are forcibly discharged.

These are intended to achieve the above-mentioned object.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below with reference to FIG.
It will be described with reference to FIG. Here, in FIG.
To the first migration electrode 5 and the second migration electrode 1 shown in FIG.
1, illustration of the support member 13 and the cover member 14 is omitted.

1 to 4, a plurality of ejection electrodes 2a to 2h are formed on a substrate 1 (base substrate). In this embodiment, the substrate 1 is an insulator made of Si material. Alternatively, the substrate 1 may be made of a glass material or the like. A plurality of ejection electrodes 2a to
Each of 2h is formed in a strip shape, and in the present embodiment, 8 pieces are formed in parallel. The ejection electrodes 2a to 2h are formed by patterning a conductive material such as chromium sputtered on the entire surface of the substrate 1 by photolithography. In the present embodiment, each of the ejection electrodes 2a to 2h has 3
They are formed at a pitch of 00 dpi, that is, at intervals of about 85 μm.

The ejection-side tips of the ejection electrodes 2a to 2h are formed in a sharp needle shape. In addition, this discharge electrode 2
The first wiring layer H ₁ which a~2h is formed, the other discharge electrode 2 a to 2 h, the ejection control electrode 3a, a part 3a ₁ of _{3b, 3a 2, 3b 1,} 3b 2 is the discharge Electrode 2a-
It is formed parallel to 2h. The ejection electrodes 2a to 2h are
The upper and lower parts of FIG. 1 are divided into two sets, L and U, each having four sets. Part of the discharge control electrodes 3a, 3b 3a ₁ ,
_Two 3a ₂ , 3b ₁ and 3b ₂ are formed corresponding to the sets L and U of ejection electrodes, respectively.

[0025] The first upper wiring layer H ₁ is formed on the first insulating layer Z ₁ is one side, and the second wiring layer H ₂ provided further upper layer of the first insulating layer Z ₁ There is. In the second wiring layer H ₂ , a part 3a _{3 of} the ejection control electrodes 3a, 3b,
3a _4, 3b _3, 3b ₄ is formed in the direction orthogonal to the ejection electrode 2a~2h formed on the first wiring layer H _1. Part of these discharge control electrodes 3a, 3b 3a ₃ , 3a
₄ , 3b ₃ and 3b ₄ are portions 3a _{1 of} the ejection control electrodes 3a and 3b formed in the _first wiring layer H ₁ through a plurality of through holes th provided in the _first insulating layer Z _1. , 3
It is connected to a ₂ , 3b ₁ and 3b ₂ . This allows
The two ejection control electrodes 3a and 3b are each formed in an L shape. The L-shaped discharge control electrode 3
A side of a and 3b has L sets of ejection electrodes 2a to 2d, respectively.
And all of the U sets of ejection electrodes 2e to 2h are traversed on the ejection side.

In the second wiring layer H ₂ , four strip-shaped short-circuit members for short-circuiting the L ejection electrodes 2a to 2d and the U ejection electrodes 2e to 2h in a one-to-one correspondence. 4a
4d are arranged so as to be orthogonal to the ejection electrodes 2a to 2h. The short-circuit members 4a to 4d are provided with the ejection electrodes 2a and the ejection electrodes 2e, the ejection electrodes 2b and the ejection electrodes 2f, the ejection electrodes 2c and the ejection electrodes 2g, and the ejection electrodes 2 through the through holes th.
d and the discharge electrode 2h are short-circuited.

A second insulating layer Z ₂ is formed on one surface of the second power distribution layer H _{2, and} a first migration electrode 5 is formed on one surface of the second insulating layer Z ₂ . This first migration electrode 5
Is formed by photolithography, and its tip end on the ejection side is set at a position slightly retracted from the tips of the ejection electrodes 2a, ... And the ejection control electrodes 3a, 3b, as shown in FIG. The electrode width of the first migration electrode 5 is
As shown in FIGS. 3 to 4, both sleeves are set to be slightly narrower than the second insulating layer Z ₂ and have an electrode width corresponding to the width of the ink flow path 6. Then, side walls 10 defining the ink flow path 6 are provided upright from both sleeve portions of the second insulating layer Z ₂ where the first migration electrode 5 is not formed. Further, a third insulating layer Z ₃ is formed on one surface of the upper layer of the first migration electrode 5.

The ink flow path 6 is formed in the upper layer of the third insulating layer Z ₃ . Specifically, the ejection control electrode 3
a, a portion of 3b 3a _3, 3b each ejection electrode 2a along _three
The flow path partition walls 7, 7, ... Are arranged at positions corresponding to 2 h. The flow path partition walls 7, 7, ... Are formed in a baseball home base type in plan view, and are provided with protrusions in the ink ejection direction. As a result, a plurality of ink ejection holes (ink drawing holes) 8 are formed between the adjacent flow path partition walls 7, 7.
.. are formed. Further, also on the ink supply side opposite to the ink discharge holes 8, a plurality of flow path partition walls 9, 9 are provided at a predetermined interval in a direction orthogonal to the discharge electrodes 2a, 2b ,.
... is provided. In the present embodiment, these flow path partition walls 7, ..., 9, ... Are formed by photolithography of a photosensitive polymer film laminated on the substrate 1, and the ink flow paths 6 are slit-shaped. Thus, they are all formed to have the same predetermined thickness.

A second electrophoretic electrode 11 is provided above the ink flow path 6 and on the ink supply side in parallel with the first electrophoretic electrode 5. As shown in FIG. 2, the second electrophoretic electrode 11 has an L-shaped vertical cross section, and an end portion on the ejection side is set at a position corresponding to the first electrophoretic electrode 5. The second migration electrode 11 is provided with a plurality of ink supply ports 12 on its ink supply side surface (a connection surface with an ink chamber 15 described later), as shown in FIG. The ink supply port 12 is opened corresponding to the position of the flow path partition wall 9 on the ink supply side. In addition, the second migration electrode 11
One of the ends of the first electrode enters the _third insulating layer Z ₃ and is short-circuited with the first electrophoretic electrode 5.

Further, as indicated by symbol E in FIG. 2, a part of the second migration electrode 11 is exposed in the ink flow path 6.

A support member 13 for supporting the second electrophoretic electrode 11 is provided between the second electrophoretic electrode 11 and the ink flow path 6.
Is provided. The supporting member 13 is formed in an L-shaped longitudinal section corresponding to the shape of the second electrophoretic electrode 11, and the top plate of the ink flow path 6 is formed by using the flow path partition walls 7, ..., 9 ,. Is done. The ink supply side of the support member 13 has an ink supply port 12 formed in the second migration electrode 11.
Corresponding to, the ink supply port is similarly opened. Here, in practice, the second migration electrode 5 is formed on the surface of the support member 13 by a PSP (Photo Selectiove Plating) method, an APE method.
It is integrally formed by using (Additiive Photo Etching) method or Mold-n-Plate method.

A cover member 14 defining an ink chamber 15 on the ink supply side of the ink flow path 6 is formed on the upper layer of the second migration electrode 11. This cover member 14 is
As shown in FIG. 2, the ink provided at a predetermined interval between the insulating portion that insulates the upper surface of the second electrophoretic electrode 11 and the second electrophoretic electrode 11 on the ink supply side of the ink flow path 6. The chamber forming portion and the side wall 10 of the ink flow path 6 described above are integrally provided. In addition, the ink chamber 1 of the cover member 14
Two holes 15A for ink circulation are provided in the portion 5 and are connected to an external ink tank via a tube (not shown). As a result, a negative pressure of about 1 cmH ₂ O is constantly applied to the ink in the ink chamber,
Forced ink circulation is performed.

Here, the ejection electrodes 2a to 2h, the ejection control electrodes 3a and 3b, and the first and second migration electrodes 5 and 11 are provided.
Is connected to an external voltage drive unit and is set to a predetermined potential (not shown).

Next, the overall operation of this embodiment will be described.
Here, the ink used in this embodiment is a dispersion of fine particles of a thermoreversible resin colored with a charge control agent, that is, a toner in a petroleum-based organic solvent (in-paraffin), and the toner has a zeta potential. The positive polarity is apparently charged. Further, the electrostatic ink jet recording head of the present embodiment is arranged and operates so as to face a recording electrode (not shown) provided on the ink ejection side thereof with a predetermined interval. The recording electrode is grounded, and the recording paper is arranged between the recording electrode and the ink ejection side of the recording head.

First, while the ink is circulated in the ink chamber 15 and the ink has permeated into the slit-shaped ink flow path 6, the first and second electrophoretic electrodes 5 and 11 are driven by an external voltage driver. When a positive voltage is applied to the electrodes, an electrostatic force (repulsive force) is generated between the charged toner in the ink and the migration electrodes 5 and 11. As a result, the charged toner in the ink flow path 6 is urged toward the ink discharge holes 8, 8, ..., And in each ink discharge hole 8, 8, ..., Due to the surface tension of the ink, the flow path partition walls 7, 7. An ink meniscus I is formed on the protruding portion of. The vertical cross section of the ink meniscus I has a triangular shape with one side recessed as shown in FIG. This is the first and the second rather than the tips of the flow path partition walls 7, 7, ....
This is because the distal ends of the migration electrodes 5 and 11 are set to a slightly retracted position.

Next, when one of the ejection electrodes 2a to 2h to eject ink is selected, first,
The voltage of the ejection control electrodes of the set not including the selected ejection electrode is set to the low level. For example, the ejection electrode 2b
If is selected, the ejection control electrode 3b belonging to the electrode set U not including the ejection electrode 2b is set to the low level. As a result, the charged toner that has formed the ink meniscus at the tips of the U sets of flow path partition walls 7, 7, ... Receives an attractive force generated between the charge toner and the ejection control electrode 3b, and the ink flow path 6
Somehow pulled back in.

Next, when the voltage of the selected ejection electrode is set to a high level, an electric field is generated between the ejection electrode and the recording electrode facing the recording head, thereby causing an ink meniscus. The formed charged toner gathers at the needle-shaped tip of the ejection electrode, forms a toner group, and flies toward the recording electrode. As a result, the ink adheres to the recording paper provided between the recording head and the recording electrode, and an image is formed.

For example, when the ejection electrode 2b is set to a high level, the toner flies from the tip position of the ejection electrode 2b toward the recording paper. At this time, the U sets of ejection electrodes 2f that are short-circuited with the ejection electrodes 2b are also set to the high level. However, since the U sets of ejection control electrodes 3b are set to the low level in advance, the toner does not fly from the ejection electrodes 2f due to the relationship between the force of the electrostatic force and the voltage application time.

Specifically, the relationship between the voltage applied to the ejection electrode and the voltage applied to the ejection control electrode is as shown in FIG. FIG. 5A shows the relationship between the voltages (driving pulses) of the ejection electrodes and the ejection control electrodes that prevent the ejection of toner. In the above example, the U sets of ejection electrodes 2f and ejection control electrodes 3b correspond. First, the ejection control electrode is set to a low level (low potential), and immediately thereafter, the ejection electrode is set to a high level (high potential). After that, the voltage applied to the ejection electrode is returned to the initial state, and subsequently, the voltage applied to the ejection control electrode is returned to the initial state. Also, FIG.
(B) shows the voltage relationship between the ejection electrode and the ejection control electrode on which the toner is ejected. In the above example, the L sets of ejection electrodes 2b and ejection control electrodes 3a correspond. in this case,
The ejection electrode is set to high level (high potential), then
The voltage applied to the ejection electrode is returned to the initial state, but the potential of the ejection control electrode is not changed.

The toner ejected onto the recording paper by the above-mentioned ink ejection operation is then heated by a heater and fixed (not shown).

The ink ejection holes 8 are formed by the flight of the charged toner.
The insufficient charged toner in the vicinity is supplied from the ink flow path 6. Specifically, the charged toner in the ink flow path 6 is electrophoresed from the ink chamber 15 side to the ink ejection hole 8 by the action of the electric field which is diverged from the migration electrodes 5 and 11 toward the ink ejection side, and is transferred to the ink meniscus I. Supplied. Then, the ejection electrode is appropriately selected and the above-mentioned flying operation is continuously performed.

Here, after the positively charged toner flies, the ink near the ejection electrode is filled with the negative counter ions. This counter ion is applied to the migration electrodes 5 and 1.
Since the electric field formed between 1 and the ejection electrode is disturbed, it becomes impossible to sufficiently replenish the toner by electrophoresis. In this embodiment, since the second migration electrode 11 is exposed in the ink flow path 6 and is directly short-circuited with the ink,
Excessive counter ions that cause the above inconvenience are forcibly discharged and removed.

As described above, in the present embodiment, since the ejection electrodes for ejecting the charged toner and the ejection control electrodes are laminated via the insulating layer, the overall size of the recording head can be reduced.

Further, when supplying the charged toner from the ink chamber side to the ink ejection hole side, a migration electrode surrounding the ink flow path is formed and the charged toner is electrophoresed. There is no need to provide a body,
Since the charged toner can be supplied without contact,
The toner can be supplied at a higher speed than in the conventional example using the porous body, and high-speed and high-quality printing can be realized.

Further, the migration electrode is photolithography, P
Since it can be formed relatively easily using the SP method, the APE method, the Mold-n-Plate method, etc., the manufacturing process is simplified and the manufacturing is simplified as compared with the conventional example in which the porous body is arranged in the ink flow path. The cost can be reduced.

In addition to this, since the ejection electrodes are formed in a strip shape, it is possible to form the ejection electrodes at a high density, which is advantageous in improving the printing resolution and downsizing the recording head.

Further, since the ejection control electrodes are formed in the direction perpendicular to the ejection electrodes, the ejection operations of the ejection electrodes can be collectively blocked by one ejection control electrode. The number of control electrodes can be reduced, and thus the recording head can be downsized. Further, since the number of ejection control electrodes is reduced, there is an advantage that the configuration of the drive device for the recording head can be simplified.

Further, the plurality of ejection electrodes are divided into two sets, the corresponding ejection electrodes of each set are short-circuited, and the ejection electrodes for ejecting ink are selected in relation to the voltage applied to the ejection control electrodes. Therefore, the number of wirings to the external driving device can be reduced to half of the number of ejection electrodes, which causes inconvenience such as poor contact between the connecting portion between the recording head and the external driving device. As a result, the reliability of the ejection operation can be improved. Even when the number of discharge electrode bundles is increased to three or more, by short-circuiting the corresponding discharge electrodes of each set, the number of contact points of the discharge electrodes connected to the external drive device does not change, and the added set is expanded. It only increases the number of contacts of the discharge control electrode for a few minutes. Therefore, there is also an advantage that a flexible design change can be easily made according to the configuration of the recording apparatus.

Further, since a part of the migration electrode is exposed in the ink flow path, excess counter ions generated near the ejection electrode after the flying of the charged toner are forcibly discharged to cause electrophoresis. The energizing electric field can be normalized, which makes it possible to constantly and stably supply the charged toner to the vicinity of the ink ejection holes.

Here, in the present embodiment, the respective electrodes are stacked on the substrate in the order of the discharge electrode, the discharge control electrode, and the first electrophoretic electrode, but the stacking order of these electrodes is not limited to this. Absent. The first migration electrode and the second migration electrode may be respectively provided on the side surface of the ink flow path. The ejection electrodes do not have to be strip-shaped. The discharge electrode short-circuit member does not have to be provided directly to the discharge electrode. The bundle of ejection electrodes may be two or more.

[0051]

Since the present invention is constructed and functions as described above, according to the present invention, since the ejection electrode for ejecting the charged toner and the ejection control electrode are formed by laminating via the insulating layer, the entire recording head can be formed. The size can be reduced.

According to the second or third aspect of the present invention, when the charged toner is supplied from the ink chamber side to the ink ejection hole side, the migration electrode surrounding the ink flow path is formed and the charged toner is electrophoresed. It is possible to supply charged toner in a non-contact manner without providing a porous body as in the conventional example, so that it is possible to supply toner at a higher speed than the conventional example using the porous body In addition, high quality printing can be realized.

According to the fourth aspect of the invention, since the migration electrode is integrally formed with the support member by using, for example, the PSP method, the APE method, the Mold-n-Plate method, etc., the porous body is formed in the ink flow path. The manufacturing process can be simplified and the manufacturing cost can be reduced as compared with the conventional example in which the above-mentioned arrangement is provided.

According to the fifth aspect of the invention, since the ejection electrodes are formed in a strip shape, the ejection electrodes can be formed at a high density, which is advantageous in improving the printing resolution and miniaturizing the recording head.

According to the sixth aspect of the invention, since the strip-shaped ejection control electrodes are formed in a direction orthogonal to the plurality of ejection electrodes, the ejection operations of the plurality of ejection electrodes are collectively performed by one ejection control electrode. The number of ejection control electrodes can be reduced, and the size of the recording head can be reduced. Further, since the number of ejection control electrodes is reduced, there is an advantage that the configuration of the drive device for the recording head can be simplified.

In the invention according to claim 7, the plurality of ejection electrodes are divided into a plurality of groups, and the corresponding ejection electrodes of each group are short-circuited,
Since the ejection electrode for ejecting ink is selected in relation to the voltage applied to the ejection control electrode, the number of wirings with an external driving device can be reduced to half the number of ejection electrodes. As a result, it is possible to suppress the occurrence of inconveniences such as poor contact between the connecting portion between the recording head and the external driving device, and improve the reliability of the ejection operation. Also,
Even if a bundle of discharge electrodes is added, by short-circuiting the corresponding discharge electrodes of each set, the number of contact points of the discharge electrodes connected to the external drive device does not change, and the discharge control electrodes for the added number of sets are not changed. It only increases the number of contacts. For this reason,
There is also an advantage that a flexible design change can be easily made according to the configuration of the recording apparatus.

In the eighth aspect of the invention, since a part of the migration electrode is exposed in the ink flow path, it is necessary to forcibly discharge excess counter ions generated near the ejection electrode after the flying of the charged toner. As a result, the electric field that urges the electrophoresis can be normalized, and therefore, the charged toner can be stably supplied to the vicinity of the ink ejection hole at all times.

As described above, according to the present invention, it is possible to provide an excellent electrostatic ink jet recording head which has never been obtained.

[Brief description of drawings]

FIG. 1 is a partially omitted plan view showing an embodiment of the present invention.

FIG. 2 is a vertical sectional view taken along the line AA in FIG.

3 is a vertical cross-sectional view taken along the line BB in FIG.

4 is a vertical cross-sectional view taken along the line C-C in FIG.

FIG. 5 is a diagram showing a temporal change of a drive pulse applied to the ejection electrode and the ejection control electrode in the embodiment shown in FIG. 1, and FIG. 5A shows each case when ink ejection is blocked. Drive pulses are shown, and FIG. 5B shows each drive pulse when ink is ejected.

[Explanation of symbols]

2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h Ejection electrode 3a, 3b Emission control electrode 4a, 4b, 4c, 4d Ejection electrode short-circuit member 5, 11 Migration electrode 6 Ink flow channel 8 Ink ejection hole 13 Support Member L, U Discharge electrode pair Z ₁ , Z ₂ , Z ₃ Insulating layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hitoshi Minemoto 5-7-1, Shiba, Minato-ku, Tokyo Inside NEC Corporation (72) Inventor Yoshihiro Hagiwara 5-7-1, Shiba, Minato-ku, Tokyo Inside NEC Corporation

Claims (8)

[Claims] 1. An ink chamber for storing ink containing charged toner, a slit-shaped ink channel communicating with the ink chamber, an ink ejection hole provided at the tip of the ink channel, and an ink ejection hole A discharge electrode that is provided in the vicinity and that forms an electric field that applies a discharge force to the charged toner contained in the ink that has accumulated in the ink flow path, and prevents discharge of the charged toner from the ink discharge hole that is attached to this discharge electrode In the electrostatic ink jet recording head provided with an ejection control electrode for forming an electric field, an electrostatic ink jet recording head characterized in that the ejection electrode and the ejection control electrode are laminated and arranged via an insulating layer. 2. The electrostatic ink jet recording head according to claim 1, wherein at least one of the surfaces surrounding the ink flow path is connected to the connection surface with the ink chamber and the connection surface with the ink chamber and faces each other. An electrostatic ink jet recording head, characterized in that electrophoretic electrodes for urging the electrophoretic migration of the charged toner are provided on one set of side surfaces. 3. The electrostatic ink jet recording head according to claim 1, wherein among the surfaces surrounding the ink flow path, a top surface and a bottom surface connected to the connection surface with the ink chamber and the connection surface with the ink chamber. And an electrophoretic electrode for urging the electrophoretic migration of the charged toner, and a supporting member for the electrode disposed on the upper surface is provided between the electrophoretic electrode disposed on the upper surface and the ink flow path. An electrostatic ink jet recording head characterized in that 4. The electrostatic ink jet recording head according to claim 3, wherein the electrode disposed on the upper surface of the ink flow path and the supporting member are integrally formed. 5. The electrostatic ink jet recording head according to claim 1, wherein the discharge electrode is formed in a strip shape along the ink moving direction of the ink flow path. 6. The electrostatic discharge device according to claim 5, wherein a plurality of the strip-shaped ejection electrodes are formed in parallel on the substrate, and the ejection control electrodes are formed in a strip shape orthogonal to the plurality of ejection electrodes. Type inkjet recording head. 7. The electrostatic ink jet recording head according to claim 6, wherein at least two pairs of the plurality of ejection electrodes and one ejection control electrode are formed in parallel on the substrate, and each of these is formed. An electrostatic ink jet recording head characterized in that a pair of corresponding discharge electrodes are short-circuited by strip-shaped short-circuit members provided in parallel with the discharge control electrodes. 8. The electrostatic ink jet recording head according to claim 2, wherein a part of the migration electrode is exposed in the ink flow path.